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The hair growth promoting effect of ascorbic acid 2-phosphate, a long-acting Vitamin C derivative [3]
... Hair loss or alopecia is a common condition that poses a psychological, social, and economic burden, thereby hindering the quality of life [5]. Therefore, several studies are being conducted to treat and prevent hair loss, including the development of drugs and cosmetics [6][7][8][9]. Owing to the increased medical and cosmetic demands in hair care, several studies are being conducted to screen for candidate therapies to promote hair growth or prevent hair loss [10]. However, the 2D-cultured cells traditionally used for cell-based screening assays are physiologically different from in vivo cells [11]. ...
... To validate the growth-promotion effect of hair follicle growth-promoting substances in hair follicle-like structure, three kinds of reported hair follicle growth-promoting substances (minoxidil ( [6]; Figure 4A), tofacitinib ( [7]; Figure 4B), and ascorbic acid ( [8]; Figure 4C)) were applied to iHFLS during the formation process and culture period. We confirmed the enhanced elongation of the keratinocyte layer in hair-promoting agent-treated iHFLS in a dose-related manner, with an increased minimum of 12.9% in the minoxidil 1.25 μM-treated group and a maximum of 57.4% in the tofacitinib 2 μM-treated group. ...
... To validate the growth-promotion effect of hair follicle growth-promoting substances in hair follicle-like structure, three kinds of reported hair follicle growth-promoting substances (minoxidil ( [6]; Figure 4A), tofacitinib ( [7]; Figure 4B), and ascorbic acid ( [8]; Figure 4C)) were applied to iHFLS during the formation process and culture period. We confirmed the enhanced elongation of the keratinocyte layer in hair-promoting agent-treated iHFLS in a dose-related manner, with an increased minimum of 12.9% in the minoxidil 1.25 µM-treated group and a maximum of 57.4% in the tofacitinib 2 µM-treated group. ...
We aimed to establish screening and efficacy test techniques for use in the development of hair-promoting agents. To this end, we used the dermal papilla cell (DPc)-derived immortalized cell line (SV40T-hTERT DPc) and neonatal foreskin-derived keratinocyte cell line (Ker-CT) to form an immortalized cell-based hair follicle-like structure. The SV40T-hTERT DPc spheroids exhibited a higher cell ratio in the spheroids than primary DPc spheroids, and SV40T-hTERT DPc aggregated with spheroids larger in diameter than primary DPc when the same cell number was seeded into the low-adhesion plate. Microscopic imaging and fluorescence staining results indicated that both primary and immortalized cell combinations form a hair follicle-like structure with a long-stretched keratinocyte layer under the condition that the spheroids have the same diameter as that of in vivo dermal papillary tissue in the hair follicle. The hair follicle-like structure elongation was increased upon treatment with three known hair follicle growth-promoting compounds (minoxidil, tofacitinib, and ascorbic acid) compared with that in the control group. Therefore, using immortalized cells to generate a coherent follicle-like structure, we have developed models for screening and evaluating hair-care materials commonly used in the industry.
... Magnesium ascorbyl phosphate (MAP) (Fig. 1A), a stable phosphate derivative of L-ascorbic acid has been reported to stimulate growth of dermal papilla cells in vitro (Hata and Senoo, 1989;Takamizawa et al., 2004) and induce early conversion of telogen phase to anagen phase of hair cycle in experiment with mice (Sung et al., 2006). Furthermore, MAP treatment resulted in significant elongation of hair shafts in isolated hair follicles. ...
... Furthermore, MAP treatment resulted in significant elongation of hair shafts in isolated hair follicles. Mechanism responsible for the growth stimulation of dermal papilla cells and elongation of hair shafts has been suggested that MAP induces proliferative and anti-apoptotic effects on dermal papilla cells (Sung et al., 2006). This finding provided a potential that MAP might be useful for hair growth promotion in the treatment of alopecia. ...
... As a preliminary study, we investigated hair growth promotion effect of MAP in alopecia model using black-haired mice (C57BL/6N). Concentrations of MAP tested in this study were 2.5%, 5%, 7.5%, and 10%, because previous researchers reported that MAP induced early conversion from telogen phase to anagen phase of hair growth cycle at 250 mM concentration, which is equivalent to about 7.25% of MAP (Sung et al., 2006). Hair growth quantification score in the groups treated with MAP was in proportion to the concentration of MAP up to 7.5% and plateaued above this concentration. ...
The purpose of this study was to evaluate the effect of methylsulfonylmethane (MSM) on hair growth promotion of magnesium ascorbyl phosphate (MAP) for the treatment of alopecia. Aqueous solutions of MAP 7.5% with or without MSM 1%, 5% or 10% were prepared and applied onto the depilated back skin of the male mice once a day for 20 days. The degree of hair growth was evaluated by visual scoring using hair growth quantification scale (0-5, 0 being initial state and 5 being complete hair growth). In vitro transdermal penetration and intradermal retention studies of MAP were performed with Franz diffusion cell using hairless mice skin. Hair growth in the group treated with the aqueous solution containing MAP 7.5% and MSM 10% was comparable to or better than the result in the group treated with minoxidil 5% solution. Hair growth promotion of MAP was dose-dependently increased by the presence of MSM used in combination with MAP 7.5% solution. The in vitro transdermal penetration of the MAP was decreased in proportion to the concentration of MSM. However, intradermal retention of MAP was profoundly and dose-proportionally increased as a function of MSM concentration, reaching 802 μg/cm2 in the presence of MSM 10% (200-fold increase). The effect of MSM on hair growth promotion of MAP was dose-proportional to the concentration of MSM due to the enhanced intradermal retention of MAP in the presence of MSM. Therefore, topical application of MAP together with MSM appears to be useful for the treatment of alopecia.
... 12,13 We have recently reported that Asc 2-P stimulates the growth of human DP cells, promotes the elongation of hair shafts in hair follicles in culture, and induces early conversion from a telogen phase to an anagen phase in mice. 14 We also found that Asc 2-P induces expression of versican and CCN1 ⁄Cyr61, target genes of Wnt signalling through the b-catenin pathway. [15][16][17][18] In addition, we found that phosphatidylinositol 3-kinase (PI3K) ⁄protein kinase B (PKB) signalling and b-catenin accumulation are involved in Asc 2-P-mediated versican induction. ...
... On the other hand, we failed to find any growth promotion of ORS keratinocytes in monoculture as reported previously. 14 The neutralizing antibody against IGF-1 significantly attenuated the Asc 2-P-induced growth promotion of keratinocytes (Fig. 3, compare lanes 2 and 3), demonstrating that the growth induction is largely due to IGF-1. In contrast, preimmune goat IgG did not reverse the Asc 2-P-induced growth promotion of keratinocytes (Fig. 3, lane 4). ...
... We have previously reported that Asc 2-P acts directly on DP cells, activates expression of genes known as targets of the canonical Wnt signal which is involved in hair growth, and indeed promotes hair growth in mice. [14][15][16] In this study, we first examined whether IGF-1, which is well known to promote hair growth, is involved in hair growth stimulation by Asc 2-P. We observed that IGF-1 is induced after Asc 2-P treatment (Fig. 1). ...
l-Ascorbic acid 2-phosphate (Asc 2-P), a derivative of l-ascorbic acid, promotes elongation of hair shafts in cultured human hair follicles and induces hair growth in mice.
To investigate whether the promotion of hair growth by Asc 2-P is mediated by insulin-like growth factor-1 (IGF-1) and, if so, to investigate the mechanism of the Asc 2-P-induced IGF-1 expression.
Dermal papilla (DP) cells were cultured and IGF-1 level was measured by reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay after Asc 2-P treatment in the absence or presence of LY294002, a phosphatidylinositol 3-kinase (PI3K) inhibitor. Also, hair shaft elongation in cultured human scalp hair follicles and proliferation of cocultured keratinocytes were examined after Asc 2-P treatment in the absence or presence of neutralizing antibody against IGF-1. In addition, keratinocyte proliferation in cultured hair follicles after Asc 2-P treatment in the absence or presence of LY294002 was examined by Ki-67 immunostaining.
IGF-1 mRNA in DP cells was upregulated and IGF-1 protein in the conditioned medium of DP cells was significantly increased after treatment with Asc 2-P. Immunohistochemical staining showed that IGF-1 staining is increased in the DP of cultured human hair follicles by Asc 2-P. The neutralizing antibody against IGF-1 significantly suppressed the Asc 2-P-mediated elongation of hair shafts in hair follicle organ culture and significantly attenuated Asc 2-P-induced growth of cocultured keratinocytes. LY294002 significantly attenuated Asc 2-P-inducible IGF-1 expression and proliferation of follicular keratinocytes in cultured hair follicles.
These data show that Asc 2-P-inducible IGF-1 from DP cells promotes proliferation of follicular keratinocytes and stimulates hair follicle growth in vitro via PI3K.
... We have recently reported that L-ascorbic acid 2phosphate magnesium salt (Asc 2-P), a derivative of L-ascorbic acid (Vitamin C), stimulates the growth of human dermal papilla cells, promotes the elongation of hair shafts in hair follicles in culture, and induces early conversion from a telogen phase to an anagen phase in mice [3]. These results suggest that Asc 2-P regulates expression of genes in dermal papilla cells and thereby affects hair growth and cycling. ...
... For example, CTGF may play an important role in induction and maintenance of hair growth phase (anagen) by inhibition of molecules such as BMP and TGF-b family proteins which are important factors for regulating telogen-to-anagen and anagen-to-catagen transition in hair cycling [1]. In this regard, it is interesting to note that Asc 2-P not only promotes the elongation of human hair shafts in isolated hair follicles in culture [3], but also induces early Letter to the Editor 257 conversion from a telogen phase to an anagen phase in mice [3]. ...
... For example, CTGF may play an important role in induction and maintenance of hair growth phase (anagen) by inhibition of molecules such as BMP and TGF-b family proteins which are important factors for regulating telogen-to-anagen and anagen-to-catagen transition in hair cycling [1]. In this regard, it is interesting to note that Asc 2-P not only promotes the elongation of human hair shafts in isolated hair follicles in culture [3], but also induces early Letter to the Editor 257 conversion from a telogen phase to an anagen phase in mice [3]. ...
... Various vitamins have been examined in several biological models, including cell lines, murine and human studies, demonstrating their significant impact as key modulators of hair growth, as illustrated in Table 1. Recent studies demonstrate that vitamins exert a regulatory effect on the hair growth cycle, as illustrated in Figure 1 [9][10][11][12][13][14][15][16][17]. Induces proliferation of dermal papilla cells in culture, and in C57BL/6 mice induced an earlier transition from telogen to anagen and increased the number of follicles [13] Ascorbic Acid 2-Phosphate ...
... Recent studies demonstrate that vitamins exert a regulatory effect on the hair growth cycle, as illustrated in Figure 1 [9][10][11][12][13][14][15][16][17]. Induces proliferation of dermal papilla cells in culture, and in C57BL/6 mice induced an earlier transition from telogen to anagen and increased the number of follicles [13] Ascorbic Acid 2-Phosphate ...
... L-Ascorbic acid-2-phosphate magnesium salt, a phosphate derivative of L-ascorbic acid (AA), is known to stimulate growth of human dermal fibroblast cells while AA has no benefit on the growth of the cells (Hata and Senoo, 1989;Takamizawa et al., 2004). A2P also demonstrated growth stimulation of dermal papilla cells in vitro and early conversion from telogen phase to anagen phase in experiment with mice (Sung et al., 2006). Furthermore, A2P treatment resulted in significant elongation of hair shafts in isolated hair follicles. ...
... Furthermore, A2P treatment resulted in significant elongation of hair shafts in isolated hair follicles. Mechanism responsible for the growth stimulation of dermal papilla cells and elongation of hair shafts has been suggested that A2P induces proliferative and anti-apoptotic effects on dermal papilla cells (Sung et al., 2006). This finding provided a potential that A2P might be useful for the treatment of androgenetic alopecia. ...
Transdermal formulation of L-ascorbic acid 2-phosphate magnesium salt (A2P) was prepared using multilamellar vesicles (MLV). A2P was either physically mixed with or entrapped into three different MLVs of neutral, cationic, and anionic liposome vesicles. For the preparation of neutral MLVs, phosphatidylcholine (PC) and cholesterol (CH) were used. For cationic and anionic MLVs, dioleoyl-trimethylammonium-propane and dimyristoyl glycerophosphate were added as surface charge inducers, respectively, in addition to PC and CH. Particle size of the three A2P-loaded MLVs was submicron, and polydispersity index revealed homogenous distribution of the prepared MLVs except neutral ones. Skin penetration study with hairless mouse skin showed that both physical mixtures of A2P with empty MLVs and A2P-loaded MLVs increased penetration of the drug compared to aqueous A2P solution. During the penetration, however, significant amount of the drug was metabolized into L-ascorbic acid, which has no beneficial effect on stimulation of hair growth. Out of the physical mixtures and A2P-loaded MLVs tested, physical mixture of A2P with empty cationic MLV resulted in the greatest skin penetration and retention in hairless mouse skin.
... 7 L-Ascorbic acid 2-phosphate (Asc 2-P), a long-acting ascorbic acid derivative, has been shown to induce hair growth in animal studies and in in vitro human hair follicles. 8 ...
UNSTRUCTURED
Oral supplements are a growing industry, garnering the attention of patients and medical professionals alike. The marketplace for oral supplements is flooded with a wide range of products offering broad availability and convenience, and supported by a spectrum of customer testimonials. Currently, these supplements are regulated as foods rather than drugs, under the governance of the Food and Drug Administration (FDA). The “food” classification allows these products to become available to customers without proof of meeting the efficacy and safety standards required of pharmaceuticals to enter the marketplace. In line with the surge in popularity of oral supplements, patients are increasingly looking to these medical alternatives as a method to alleviate and potentially treat their atopic dermatitis (AD). To ensure physicians are providing the best care options in the treatment of AD, it is paramount that they understand the utility, safety, and knowledge gaps associated with each type of dietary supplement. Currently, there are research gaps related to the lack of clinical trials investigating dietary supplements, and the fact that existing studies are largely limited to in-vitro or animal-based studies. We undertook a literature review designed to objectively identify the effectiveness of oral supplements in the treatment of patients with AD. With the exception of Vitamin B12, magnesium, and apple cider vinegar, this review does not address the efficacy of topical formulations in AD.
... That is consistent with literature data showing that DHT increases intracellular ROS levels and thereby induces cell death and senescence [30] [53]. Other antioxidants, such as ascorbic acid, were shown to stimulate the growth of HFDPCs and promote hair shaft elongation in vitro and in vivo [54]. Thus, OMWW can protect the essential hair follicle cells from oxidative stress or DHT and reduce ROSinduced hair loss through its antioxidant properties. ...
... 7 L-Ascorbic acid 2-phosphate (Asc 2-P), a long-acting ascorbic acid derivative, has been shown to induce hair growth in animal studies and in in vitro human hair follicles. 8 ...
... We chose C57BL/6 mice for our study based on our review of prior related studies [11,20]. Female C57BL/6 mice weighing 15-20 g (six weeks old) were obtained from the National Laboratory Animal Center (Taipei, Taiwan); mice were randomly grouped and cared for in a sterilized cage independent animal unit under a 12-hour light/darkness cycle in the Animal Technology Institute Taiwan (ATIT). ...
Despite minoxidil and finasteride already being approved by the Food and Drug Administration (FDA) for the treatment of hair loss, it is important to identify new and innovative treatments for hair loss, such as looking for a solution in Chinese herbal medicine. One such treatment to consider is BeauTop (BT), whose primary ingredients include Panax japonicus (T.Nees), C.A. Mey. (Araliaceae), Astragalus membranaceus (Fisch) Bunge (Fabaceae), Angelica sinensis (Oliv.) Diels (Apiaceae), Ligustrum lucidum W.T. Aiton (Oleaceae), Rehmannia glutinosa (Gaertn.) DC. (Plantaginaceae), and Eclipta prostrata (L.) L. (Compositae). The aim of this study was to evaluate whether BT can promote hair growth in C57BL/6 mice and to investigate hair coverage, the expression of vascular endothelial growth factor (VEFG), and the numbers of hair follicles in growth phase after oral administration. A total of 12 C57BL/6 mice were divided into two groups: control group and treatment group BT. BT was administered orally as an extract at a volume of 0.6 g/kg. The control group was treated with distilled water. Each group was treated once a day for 12 consecutive days. To observe the expression of VEGF distribution, the number of hair follicles and the hair coverage were examined on days 4, 8, and 12. By comparing the treatment group and control group, we found that VEGF in the BT group on day 8 presented with a higher area percentage than the control group (p value = 0.003). Hair follicle counting results showed that the BT group was significantly higher than the control group on day 8 (p value = 0.031). Furthermore, hair coverage was shown to be significantly increased in the treatment group BT on day 8 (p value = 0.013). Taken together, these results suggest that Chinese medicine (BT) possesses the potential effect of promoting hair growth through VEGF expression. VEGF is considered the most important mediator for the process of angiogenesis involved in hair growth development.
... 7 L-Ascorbic acid 2-phosphate (Asc 2-P), a long-acting ascorbic acid derivative, has been shown to induce hair growth in animal studies and in in vitro human hair follicles. 8 ...
Hair supplements are a vast and growing industry. Patients often turn to oral supplements to address hair concerns as they are easily accessible. There are numerous products on the market, many with thousands of reviews (both positive and negative). Nutritional supplements are regulated by the FDA as foods instead of drugs, meaning they do not have to prove their efficacy and safety before becoming available to consumers. While some oral supplements have strong evidence supporting their use for hair growth, many ingredients have not been tested in clinical trials, have only in vitro evidence for hair growth, or have only been tested in animals. Given these industry characteristics, it is important for dermatologists to be aware of the safety and utility of these ingredients to provide appropriate counseling to their patients. The goal of this review is to evaluate the efficacy of popular hair growth oral supplement ingredients and formulations. This review does not address the topical formulations of these ingredients and their effects on hair growth.
... 5,15 Continuous efforts are being made to research other benefits of vitamin C, including the effects of vitamin C on hair growth, wound healing, smoking-related skin aging, scars, and striae. [33][34][35][36][37] ...
skin, Vitamin C has been shown to protect against photoaging, ultraviolet-induced immunosuppression, and photocarcinogenesis. it also has an antiaging eCect by increasing collagen synthesis, stabilizing collagen fibers, and decreasing collagen degradation. it decreases melanin formation, thereby reducing pigmentation. Vitamin C is the primary replenisher of vitamin e and works synergistically with vitamin e in the protection against oxidative damage. CONCLUSION: Topical Vitamin C has a wide range of clinical applications, from antiaging and antipigmentary to photoprotective. Currently, clinical studies on the efficacy of topical formulations of Vitamin C remain limited, and the challenge lies in ending the most stable and permeable formulation in achieving the optimal results.
... Furthermore, when new hair growth from dermal papilla cells in skin tissue was investigated, it was found that VC derivatives promoted the growth of cells and hair shafts in cultured human papilla cells; moreover, the growth period during the new hair growth cycle was prolonged by the proliferative and anti-apoptotic effects of VC derivatives. VC derivatives induced the secretion of growth factors, including insulin-like growth factor-1, which, in turn, proliferated and differentiated overlying keratinocytes to promote the elongation of hair shafts (9,10). ...
Background/aim:
Senescence marker protein-30/gluconolactonase knockout mice (SMP-30/GNL-KO) are a very useful model for clarifying the involvement of vitamin C (VC) in aging-related diseases. In this study, the effects of VC deficiency on skin and hair growth were investigated using SMP-30/GNL-KO mice by RNA sequencing.
Materials and methods:
SMP-30/GNL-KO mice were given water containing 1.5 g/l VC until up to 8 weeks after birth to maintain a VC concentration in their organs and plasma equivalent to that in wild-type mice. The mice were then divided into two groups: a VC(+) group, where VC was administered, and a VC(-) group, where VC was not administered. Skin samples were collected at 4 and 8 weeks after the treatment. RNA was extracted from each skin sample, followed by cDNA synthesis and RNA-seq. In addition, hair growth was compared between the VC(-) and VC(+) groups after shaving. Skin samples were collected from the shaved area for histological examination by hematoxylin & eosin (HE) staining.
Results:
RNA-seq revealed that there were 1,736 (FDR<0.001) differentially expressed genes in the VC(-) and VC(+) groups. From the functional analysis of the differentially expressed genes in the VC(-) and VC(+) groups, predicted functionalities including cell death and cytotoxicity increased in the VC(+) group. Furthermore, it was predicted that the difference in hair growth between the VC(-) and VC(+) groups was caused by the expression of genes including keratin-related genes and the Sonic hedgehog gene. It was confirmed that hair growth was significantly promoted; hair growth from hair papilla cells was also confirmed by HE staining of the shaved backs of SMP-30/GNL-KO mice in the VC(+) group.
Conclusion:
RNA-seq of the skin from VC-deficient mice showed the effects of VC deficiency on the expression of genes involved in cell growth and the hair cycle. Visual inspection suggested that changes in the expression of the genes are involved in delaying hair growth in the VC(-) group. Further research on the relationship among VC deficiency, the hair cycle, and skin cell growth may contribute to research on hair restoration and skin aging.
... Interestingly androgen-induced TGF-β1 secretion was reversed by a ROS scavenger 23 , indicating that antioxidants can promote hair growth. The well-established antioxidant, vitamin C, stimulates DPC growth and promotes hair shaft elongation in vitro and in vivo in animal experiments 24 . The potent antioxidant, green tea epigallocatechin-3-gallate, is also reported to enhance hair growth 25 . ...
Background:
Ecklonia cava is a brown alga that contains various compounds, including carotenoids, fucoidans, and phlorotannins. E. cava polyphenols (ECPs) are known to increase fibroblast survival. The human dermal papilla cell (hDPC) has the properties of mesenchymal-origin fibroblasts.
Objective:
This study aims to investigate the effect of ECPs on human hair growth promotion in vitro and ex vivo.
Methods:
MTT assays were conducted to examine the effect of ECPs on hDPC proliferation. Hair growth was measured using ex-vivo hair follicle cultures. Real-time polymerase chain reaction was performed to evaluate the mRNA expression of various growth factors in ECP-treated hDPCs.
Results:
Treatment with 10 µg/ml purified polyphenols from E. cava (PPE) enhanced the proliferation of hDPCs 30.3% more than in the negative control (p<0.001). Furthermore, 0.1 µg/ml PPE extended the human hair shaft 30.8% longer than the negative control over 9 days (p<0.05). Insulin-like growth factor-1 (IGF-1) mRNA expression increased 3.2-fold in hDPCs following treatment with 6 µg/ml PPE (p<0.05). Vascular endothelial growth factor (VEGF) mRNA expression was also increased 2.0-fold by 3 µg/ml PPE (p<0.05). Treatment with 10 µg/ml PPE reduced oxidative stress in hDPCs (p<0.05).
Conclusion:
These results suggest that PPE could enhance human hair growth. This can be explained by hDPC proliferation coupled with increases in growth factors such as IGF-1 and VEGF. Reducing oxidative stress is also thought to help increase hDPCs. These favorable results suggest that PPE is a promising therapeutic candidate for hair loss.
... APMg is known to stimulate the growth of human dermal fibroblasts and osteoblasts [2]. It also promotes hair growth in in vitro and in vivo experiments [3][4][5]. The effect of APMg on hair growth is achieved by the high production of IGF-1 along with versican (the target gene of Wnt/ β-catenin), alkaline phosphatase expression in cultured dermal papilla cells, and early progression of the telogenanagen transition observed in animal experiments. ...
We recently reported that L-ascorbic acid 2-phosphate (AP) stimulates the growth of human dermal papilla (DP) cells, induces secretion of IGF-1 from the DP cells to promote hair shafts elongation in cultured human hair follicles, and triggers early progression from the telogen to anagen phase in mice. Since the magnesium salt of AP (APMg) is a highly hydrophilic ionic molecule, it is not easy to deliver this reagent to the skin or hair follicles by topical application alone. In order to enhance skin penetration of APMg without changing any molecular properties, a non-invasive ionto- phoretic delivery method was introduced. Iontophoresis of the negatively charged APMg under the electrode bearing same charge (cathode) significantly enhanced the in vitro penetration of APMg into a Franz cell equipped with mouse dorsal skin. In contrast, iontophoretic movement with the anode inhibited APMg penetration achieved with passive dif- fusion alone. The effect of iontophoresis on enhancing the penetration of APMg was also found to be much higher in the skin of hairy mice (3 - 8 times) compared to hairless mice (1.5 - 2.5 times). These findings indicated that iontopho- retic movement induced the transfollicular pathway more strongly and effectively than the transdermal pathway. This phenomena was also demonstrated by the in vivo iontophoretic delivery of sodium fluorescein using hairy and hairless mice. The degree of iontophoretic enhancement during APMg penetration was also dependent on various conditions such as current density and application duration.
... This hair growth-promoting effect was mediated by activation of the mitogen-activated protein (MAP) kinase/extracellular signal-regulated kinase (ERK) kinase pathway and its protective action on transforming growth factor (TGF)-b1-induced apoptosis (Takahashi et al., 2003). Ascorbic acid 2-phosphate promoted hair growth by inducing early telogen-to-anagen phase conversion, promoting dermal papilla cell (DPC) growth, and elongating shafts in hair follicles (Sung et al., 2006). Cyclosporin A exerted hair-growing effects by downregulating negative hair-growing factors in hair epithelial cells (Harmon et al., 1995;Takahashi and Kamimura, 2001). ...
BP201, porcine lung tissue-derived phospholipids, consists of phosphatidylcholine as a major phospholipid species. BP201 promoted hair growth after application onto the shaved backs of BALB/c and C3H mice. Its effect was enhanced when applied together with minoxidil (MNX) in C3H mice. When the tissue specimens prepared from the shaved skins of BP201-treated and control mice were microscopically examined, the total numbers of hair follicles in both anagen and telogen phases of BP201-treated mice were significantly higher than those of control mice. The numbers of hair follicles in the anagen phase of BP201-treated mice were also higher than those of control mice. In combination with MNX, BP201 further increased the total number of hair follicles, but did not alter the percentage of hair follicles in the anagenic phase. BP201 also increased the proliferation of human hair follicle dermal papilla cells. Collectively, BP201 possesses hair growth promoting potential, which would suggest its use singly or in combination for hair growth products.
... Three replicates were kept in each case and average values were calculated. The activity of extract was measured by the following formula: Zone of inhibition of the extract AI (Activity index) = Zone of inhibition obtained for standard antibiotic drug The minimum inhibitory concentration (MIC) value of extracts was determined by serial dilution method (Ibekwe et al., 2001; Sung et al., 2006). The extracts were diluted to make different concentrations. ...
In the present study, leaves of Thuja orientalis were powdered and extracted by soxhlet extractor in two solvent systems that is, (E 1) ethyl acetate: chloroform: ethanol (40: 30: 30) and (E 2) methanol: distilled water (70:30). This study conferred the screening of phytochemical constituents, antioxidant activity and antibacterial activity of crude E 1 and E 2 extract and its fractions. Antioxidant activity was carried out by 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. The results indicate that E 2 extract (70% methanolic extract) had the highest antioxidant effect (85.25% inhibition) at 100 µg/ml concentration and the crude extracts (E 1 and E 2 extract) showed significant (P ≤ 0.05) inhibitory activity against both gram positive and gram negative organisms. It was active against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Agrobacterium tumefaiens. The minimum inhibitory concentrations (MICs) of E 1 extract ranged from 0.40 to 0.85 mg/ml and E 2 extract 0.55 to 1.15 mg/ml. The highest antibacterial potentiality was exhibited by E 2 extract. The fractions also exhibited antimicrobial activity against all the selected microorganisms. The study revealed that T. orientalis is a promising phytomedicine for antioxidant and antibacterial activity.
... Specifically, they found that the addition of Asc 2-P at 0.25 mM had the greatest stimulatory effect on the growth of DPCs. In contrast, there was no growth stimulating effect on the ORSCs or keratinocytes [52,53]. Cyclosporin A (CsA) has been used as a potent immunosuppressive agent for inhibition of graft rejection following organ transplantation. ...
... The ELISA and promoter assay showed that ROS induced TGF-β1 secretion in the DPCs, and that NAC inhibits androgen-induced TGF-β1 secretion at the transcriptional level ( Fig. 2 and 4). Ascorbic acid, which is a well-known antioxidant, has been shown to stimulate DP cell growth and promote hair shaft elongation in vitro and in vivo in animal experiments (17). Moreover, green tea epigallocatechin-3-gallate, which is known to have potent antioxidant effects, was reported to promote hair growth (18). ...
The progression of androgenetic alopecia is closely related to androgen-inducible transforming growth factor (TGF)-β1 secretion by hair follicle dermal papilla cells (DPCs) in bald scalp. Physiological levels of androgen exposure were reported to increase reactive oxygen species (ROS) generation. In this study, rat vibrissae dermal papilla cells (DP-6) transfected with androgen receptor showed increased ROS production following androgen treatment. We confirmed that TGF-β1 secretion is increased by androgen treatment in DP-6, whereas androgen-inducible TGF-β1 was significantly suppressed by the ROS-scavenger, N-acetyl cysteine. Therefore, we suggest that induction of TGF-β1 by androgen is mediated by ROS in hair follicle DPCs. [BMB Reports 2013; 46(9): 460-464].
... Specifically, they found that the addition of Asc 2-P at 0.25 mM had the greatest stimulatory effect on the growth of DPCs. In contrast, there was no growth stimulating effect on the ORSCs or keratinocytes [52,53]. ...
Hair follicles are complex organs composed of the dermal papilla (DP), dermal sheath (DS), outer root sheath (ORS), inner root sheath (IRS) and hair shaft. Development of hair follicles begins towards the end of the first trimester of pregnancy and is controlled by epidermal–mesenchymal interaction (EMI), which is a signaling cascade between epidermal and mesenchymal cell populations. Hair grows in cycles of various phases. Specifically, anagen is the growth phase, catagen is the involuting or regressing phase and telogen is the resting or quiescent phase. Alopecia is not life threatening, but alopecia often causes severe mental stress. In addition, the number of individuals afflicted by alopecia patients has been increasing steadily. Currently there are two methods employed to treat alopecia, drug or natural substance therapy and human hair transplantation. Although drug or natural substance therapy may retard the progress of alopecia or prevent future hair loss, it may also accelerate hair loss when the medication is stopped after prolonged use. Conversely, the transplantation of human hair involves taking plugs of natural hair from areas in which occipital hair is growing and transplanting them to bald areas. However, the number of hairs that can be transplanted is limited in that only three such operations can generally be performed. To overcome such problems, many researchers have attempted to revive hair follicles by culturing hair follicle cells or mesenchymal cells in vitro and then implanting them in the treatment area.
Vit C or L-ascorbic acid is a weak sugar acid that can occur in reduced or oxidized form structurally related to glucose. Vit C is a collective term describing several vitamers with Vit C activity in animals, including ascorbic acid, ascorbate, their salts, and some oxidized forms of the molecule, such as dehydroascorbic acid (DHA). The name “Vit C” always refers to the L-enantiomer of ascorbic acid and its oxidized forms. The D-enantiomer, which does not occur in nature and can only be synthesized artificially, lacks biological activity.
The hair follicle is subject to a constant turnover in the course of perpetual cycles through phases of proliferation, involution, and resting, with regeneration in the successive hair cycle. Understanding the basics of the hair cycle enables insight into the principles of hair growth and shedding. Many factors can lead to a pathologically increased hair loss. Whatever the cause, the follicle tends to behave in a similar way. To grasp the meaning of this generalization requires understanding the varied derangements of the normal hair cycle. Cyclic hair growth activity occurs in a random mosaic pattern with each follicle possessing its own individual control mechanism over the evolution and triggering of the successive phases, including the local milieu at the level of the stem cells. In addition, a number of systemic and environmental factors may have influence, such as hormones, cytokines and growth factors, toxins, and deficiencies of nutrients, vitamins, and energy (calories). Normal supply, uptake, and transport of proteins, calories, trace elements, and vitamins are of fundamental importance in tissues with a high biosynthetic activity such as in the course of hair cycling. It may appear that on a typical Western diet, people are not subject to nutritional deficiencies. Nevertheless, genetic diversity in nutrient requirements, inappropriate food selection or preparation, intensive physical exertion, comorbidities, and use of drugs may lead to deficiency symptoms resulting in unhealthy hair. In fact, nutritional needs fluctuate with age and with situations that occur throughout the life cycle: infancy, childhood, adolescence, pregnancy, lactation, old age, lifestyle (restricted diets, smoking, alcohol consumption), and health status (chronic disease, medications).
Numerous agents (approximately 90) are shown to stimulate hair growth in cellular and animal models in a hormetic-like biphasic dose response manner. These hormetic dose responses occur within the framework of direct stimulatory responses as well as in preconditioning experimental protocols. These findings have important implications for experimental and clinical investigations with respect to study design strategies, dose selection and dose spacing along with sample size and statistical power issues. These findings further reflect the general occurrence of hormetic dose responses within the biological and biomedical literature that consistently appear to be independent of biological model, level of biological organization (i.e., cell, organ, and organism), endpoint, inducing agent, potency of the inducing agent, and mechanism.
Background
Hair follicle cycling is dependent upon activation and differentiation of an epithelial subpopulation of cells with stem‐like characteristics. These cells express cytokeratin 15 (CK15) and are sequestered within a specialized niche termed the follicular bulge. The pathways that mediate bulge activation are poorly understood, although growing evidence suggests a role for epigenetic events.
Methods
Here we investigated murine and human hair follicles to determine whether a recently described epigenetic hydroxymethylation marker, 5‐hmC, known to mediate cell growth and differentiation, may play a role in bulge activation.
Results
We found the bulge region of murine hair follicles to demonstrate variable 5‐hmC distribution within the nuclei of CK15‐positive stem cells during early anagen, a pattern that was not associated with resting stem cells of telogen follicles which did not express 5‐hmC. Moreover, during phases of early anagen that were induced in an organ culture model, spatial alterations in bulge stem cell 5‐hmC reactivity, as assessed by dual labeling, were noted.
Conclusions
These preliminary findings suggest that 5‐hmC may play a dynamic role in bulge activation during anagen growth, and provide a foundation for further experimental inquiry into epigenomic regulation of hair follicle stem cells.
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Hair disorders such as hair loss (alopecia) and androgen dependent, excessive hair growth (hirsutism, hypertrichosis) may impact the social and psychological well‐being of an individual. Recent advances in understanding the biology of hair have accelerated the research and development of novel therapeutic and cosmetic hair growth agents. Preclinical models aid in dermocosmetic efficacy testing and claim substantiation of hair growth modulators. The in vitro models to investigate hair growth utilize the hair follicle Dermal Papilla cells (DPCs), specialized mesenchymal cells located at the base of hair follicle that play essential roles in hair follicular morphogenesis and postnatal hair growth cycles. In this review, we have compiled and discussed the extensively reported literature citing DPCs as in vitro model to study hair growth promoting and inhibitory effects. A variety of agents such as herbal and natural extracts, growth factors and cytokines, platelet‐rich plasma, placental extract, stem cells and conditioned medium, peptides, hormones, lipid‐nanocarrier, light, electrical and electromagnetic field stimulation, androgens and their analogs, stress‐serum and chemotherapeutic agents etc. have been examined for their hair growth modulating effects in DPCs. Effects on DPCs’ activity were determined from untreated (basal) or stress induced levels. Cell proliferation, apoptosis and secretion of growth factors were included as primary end‐point markers. Effects on a wide range of biomolecules and mechanistic pathways that play key role in the biology of hair growth were also investigated. This consolidated and comprehensive review summarizes the up‐to‐date information and understanding regarding DPCs based screening models for hair growth and may be helpful for researchers to select the appropriate assay system and biomarkers. This review highlights the pivotal role of DPCs in the forefront of hair research as screening platforms by providing insights into mechanistic action at cellular level, which may further direct the development of novel hair growth modulators. This article is protected by copyright. All rights reserved.
Aging is an accelerating and escalating phenomenon and reality worldwide. According to the World Health Organization, over 2 billion people will be aged 60 years and older by 2050. Aging changes every aspect of human life and influences all medical disciplines. Geriatrics and gerontology are gaining growing significance in daily practice. The pathogenesis of hair aging remains largely unknown and is now under intensive investigation. Progeria/progeroid syndromes or silver/white hair syndromes are good natural models for the study of hair aging in vivo. Aging appears to exert no effect on the number, expression, and distribution of hair follicle stem cell markers, although melanocyte stem cells are obviously affected. Chronic persistent low-grade inflammation is an essential hallmark of the aging process, so-called inflammaging, while ultraviolet irradiation, skin microbes, and stress are among the most important etiologies for inducing a proinflammatory state in skin and hair follicles. Inflammation also plays a crucial role in the pathogenesis of different hair diseases, especially alopecia areata, folliculitis decalvans, lichen planopilaris, and telogen effluvium. Antioxidants, phytoestrogens, and retinoids have been demonstrated to possess anti-aging effects on hair follicles. Antioxidation takes center stage in current anti-aging strategies, in which polyphenols are the most extensively studied and promising agents. There is preliminary evidence for beneficial effects of certain nutraceuticals such as trace elements and polyamines in the anti-aging of hair. However, the optimal dosage and application route remains to be determined. Further extensive well-controlled clinical studies are required to confirm the effects of antioxidants in the prevention, interruption, and reversal of hair aging.
Humans produce oxidant molecules either for protection, result or product of cellular metabolism by external factors such as ultraviolet radiation; on the other, antioxidant systems protect us from excess of these, but being overtaken antioxidants, a condition known as oxidative stress occurs; at this point cellular alterations promote various disease, at hair it can produce effects such as a premature aging or aggravate diseases or hair; antioxidants have been administered with the idea of preventing or ameliorating these conditions with mixed responses.
Emblica (Phyllanthus emblica Linn.) has been used to promote the growth of hair in traditional medicine, however less is known regarding its pharmacological activities in hair follicles. To investigate the effects of emblica fruit extracts in terms of hair growth stimulation, the proliferative effects of extract in HaCaT keratinocytes and Dermal Papilla (DP) cells of human hair follicles were determined by MTT assay and cell counts. The results show that emblica extract stimulated proliferation of DP cells in a concentration-dependent manner, whereas it showed minimal effect on keratinocytes, suggesting that the extract might promote hair growth by prolonging the anagen phase through the proliferative effect on DP cells.
Two types of polymeric micro-needles with 250 and lengths were prepared by a micromolding process. The geometry of dissolving micro-needles with minoxidil was investigated and the mechanical property of polymer micro-needles was also evaluated. Water dissolving micro-needles containing minoxidil were successfully inserted into skin and delivered minoxidil to the skin layer after 30 min of insertion. The observed hair growth was less when the minoxidil treatment was not applied or used without the micro-needles than that the minoxidil was applied by micro-needles. Histologically, these hair follicles became bigger, and the hair papillae were totally encircled by the hair bulbs. In this feasibility test, we show the successful delivery of minoxidil, and effective treatment of hair loss can be possible by using dissolving micro-needles with minoxidil.
Palmitoyl glycol chitosan (GCP) hydrogel has been reported as erodible controlled-release systems for the delivery of both hydrophilic and hydrophobic molecules. In this study we prepared lauroyl/palmitoyl glycol chitosan (GCL/GCP) in gel form and evaluated their application for skin delivery of the hydrophilic compound, magnesium ascorbyl phosphate (MAP), which is widely used in cosmetic formulations. Release of MAP from the polymer gels was significantly decreased with increasing concentration of GCL/GCP in the formulations in comparison with glycol chitosan (GC). In both aqueous and 10% ethanol vehicles, MAP flux was increased 1.58- to 3.96-fold of 1% GC from 1% GCL/GCP. Increase in MAP flux was correlated to the increase in GCL/GCP concentration prepared in 10% ethanol vehicle. GCL/GCP, in either water or 10% ethanol vehicles, increased the skin penetration and skin deposition of MAP in comparison with GC, hydroxypropylmethylcellulose, and carbopol, while sustaining its release from the polymer gels. Both the enhancement in skin penetration/deposition and sustained release of MAP were depended on polymer concentration. Also, with increase in polymer concentration, epidermal to dermal drug deposition ratio tended to increase, which will be beneficial to its activity in the epidermis, such as inhibition of tyrosinase and protection from UV damage. These data suggested both GCL and GCP can be applied as delivery vehicles to improve percutaneous absorption of MAP.
Vitamin C nanoliposomes were prepared by combining a conventional method (film evaporation) with dynamic high pressure microfluidization. Their physicochemical characterizations (antioxidant activity, particle size, entrapment efficiency, morphology, in vitro drug release, and storage stability) and skin permeation behavior were investigated. The results showed that vitamin C nanoliposomes, having equivalent DPPH (2, 2-Diphenyl-1-Picrylhydrazyl) free radical scavenging capacity of pure vitamin C solution without loss of their biological activity, exhibited better storage stability at 37 °C for 24 h and at 4 °C for 60 days, a more excellent sustained drug release as well as higher skin penetration rate than vitamin C liposomes.
Ascorbigen (ABG) is the predominant indole-derived compound from Brassica vegetables. In this study, we attempted to evaluate the effects of ABG on hair growth. To this end, we examined the proliferation of isolated human dermal papilla (DP) cells and keratinocytes after incubation in various concentrations (0-1.25 mM) of ABG. Furthermore, hair shaft regrowth was monitored in a mouse model of chemotherapy-induced alopecia (CIA), and hematoxylin and eosin staining was performed for histological analyses. We found that 1.25 mM ABG induced a 1.2-fold increase in the growth of DP cells, but not keratinocytes. However, ABG did not exert significant protective effects against CIA in the mouse model. These findings suggest that ABG may not be able to counteract CIA and that further investigation of the therapeutic potential of ABG in disease models is required. Copyright © 2013 John Wiley & Sons, Ltd.
The repair and management of full-thickness skin defects resulting from burns and chronic wounds remain a significant unmet clinical challenge. For those skin defects exceeding 50%-60% of total body surface area, it is impractical to treat with autologous skin transplants because of the shortage of donor sites. The possibility of using tissue-engineered skin grafts for full-thickness wound repair is a promising approach. The primary goal of tissue-engineered skin grafts is to restore lost barrier function, but regeneration of appendages, such as hair follicles, has to be yet achieved. The successful regeneration of hair follicles in immunodeficient mice suggests that creating human hair follicles in tissue-engineered skin grafts is feasible. However, many limitations still need to be explored, particularly enriching isolated cells with trichogenic capacity, maintaining this ability during processing, and providing the cells with proper environmental cues. Current advances in hair follicle regeneration, in vitro and in vivo, are concisely summarized in this report, and key requirements to bioengineer a hair follicle are proposed, with emphasis on a three-dimensional approach.
Recent studies suggested that dihydrotestosterone (DHT)-driven alteration in the autocrine and paracrine factors may be a key to androgen-potentiated balding. Also, we recently claimed that DHT-inducible dickkopf-1 (DKK-1) is one of the key factors involved in the androgen-potentiated balding. Here, we investigated whether L-ascorbic acid 2-phosphate (Asc 2-P), a derivative of L-ascorbic acid, could attenuate DHT-induced DKK-1 expression in dermal papilla cells (DPCs) from balding scalp. We observed that DHT-induced DKK-1 mRNA expression was attenuated in the presence of Asc 2-P as examined by RT-PCR analysis. In addition, we found that DHT-induced activation of luciferase reporter activity was significantly repressed when Asc 2-P was added together with DHT. Moreover, Asc 2-P repressed DHT-induced DKK-1 protein expression as examined by enzyme-linked immunosorbent assay (ELISA). Although there will be many hurdles to apply our finding to actual remedies, these results suggest that it would be worthy to evaluate Asc 2-P or its derivatives for the treatment and prevention of androgen-driven balding.
Despite the advantages of drug delivery through skin, transdermal drug delivery is only used with a small subset of drugs because most compounds cannot cross the skin at therapeutically useful rates. Recently, a new concept known as microneedle was introduced and could be used to pierce effectively to deliver drugs using micron-sized needles in a minimally invasive and painless manner. In this study, the polymer microneedle-roller was fabricated so that it can be applied into the permeation of L-ascorbic acid. Moreover, a recent publication suggested the possibility of ascorbic acid 2-phosphate as a hair restorer; hence, this study was carried out to check the effect of L-ascorbic acid itself on the hair growing rate in rats according to the presence of various application frequencies of the polymer microneedle-roller. When the polymer microneedle-roller was applied nine times with four directions into rat's shaved skin, the permeation of L-ascorbic acid increased by 10.54-fold compared to that of the absence of the polymer microneedle-roller. The histological examination revealed that the skin pretreated with various application frequencies of the polymer microneedle-roller had more transport pathways. The faster hair growing phenomenon was observed in the presence of polymer microneedle-roller compared to the absence of the polymer microneedle-roller.
Senescence marker protein-30 (SMP30) is a gluconolactonase required for vitamin C (VC) synthesis. We examined effects of VC deficiency on the mouse skin using SMP30 knockout (KO) mice. SMP30 KO or wild type male mice were weaned around day 30 of age, and fed VC-deficient diet. They were given either VC water or control water. VC deficiency for 36 days did not affect skin hydroxyproline contents, while VC deficiency for 60 days decreased the hydroxyproline levels. Levels of some collagen mRNAs were different among the groups, but did not correlate with skin VC levels. The epidermis was morphologically abnormal in VC-deficient SMP30 KO mouse at 60 days after the weaning. Interestingly, the hair cycle was not synchronized among the groups. These data suggest low susceptibility of the mouse skin to VC deficiency and involvement of VC in the regulation of keratinocyte function and hair cycle in vivo.
Electrode modification by electrochemical reduction of diazonium salts of different aryl derivatives is useful for catalytic, analytical and biotechnological applications. A simple and sensitive method for the electrocatalytic detection of ascorbic acid using disposable screen-printed carbon electrodes modified with an electrografted o-aminophenol film, via the electrochemical reduction of its in situ prepared diazonium salts in aqueous solution, is presented. The performance of two commercial SPEs as substrates for grafting of diazonium films has been compared and the grafting process optimized with respect to deposition time and diazonium salt concentration, with the modified surfaces being characterised using cyclic voltammetry. The functionalised screen-printed electrodes demonstrated an excellent electrocatalytic activity towards the oxidation of ascorbic acid shifting the overpotential from 298 and 544 mV to 160 and 244 mV, respectively vs. Ag/AgCl. DC amperometric measurements were carried out for the quantitative determination of ascorbic acid using the modified electrodes. The catalytic oxidation peak current was linearly dependent on the ascorbic acid concentration in the range of 2-20 microM, with a correlation coefficient 0.998, and a limit of detection of 0.86 microM was obtained with an excellent reproducibility (RSD% = 1.98, n = 8). The functionalised screen-printed electrodes exhibited notable surface stability, and were used as a simple and precise disposable sensor for the selective determination of ascorbic acid.
Proliferation of human skin fibroblasts was stimulated significantly by the presence of L-ascorbic acid 2-phosphate (Asc 2-P). The presence of Asc 2-P (0.1–1.0 mM) in the culture medium for 3 weeks enhanced the relative rate of collagen synthesis to total protein synthesis 2-fold as well as cell growth 4-fold. Coexistence of L-azetidine 2-carboxylic acid (AzC), an inhibitor of collagen synthesis, attenuated both effects of Asc 2-P in a dose-dependent manner. Supplementation of the medium with Asc 2-P also accelerated procollagen processing to collagen and deposition of collagen in the cell layer. Among the acidic glycosaminoglycans (GAG), another major component of extracellular matrix (ECM), deposition of sulfated forms was increased by the additive. Electron microscopic observations showed multilayered, rough endoplasmic reticulum-rich cells surrounded by dense ECM. These results indicate that Asc 2-P is useful in culture systems as a long-acting vitamin C derivative and also that it promotes reorganization of a three-dimensional tissuelike substance from skin fibroblasts in culture by stimulating collagen accumulation in the fibroblasts.
We report for the first time the successful maintenance and growth of human hair follicles in vitro. Human anagen hair follicles were isolated by microdissection from human scalp skin. Isolation of the hair follicles was achieved by cutting the follicle at the dermo-subcutaneous fat interface using a scalpel blade. Intact hair follicles were then removed from the fat using watchmakers’ forceps.
Isolated hair follicles maintained free-floating in supplemented Williams E medium in individual wells of 24-well multiwell plates showed a significant increase in length over 4 days. The increase in length was seen to be attributed to the production of a keratinised hair shaft, and was not associated with the loss of hair follicle morphology. [methyl-3H]thymidine autoradiography confirmed that in vitro the in vivo pattern of DNA synthesis was maintained; furthermore, [35S]methionine labelling of keratins showed that their patterns of synthesis did not change with maintenance.
The importance of this model to hair follicle biology is further demonstrated by the observations that TGF-βl has a negative growth-regulatory effect on hair follicles in vitro and that EGF mimics the in vivo depilatory effects that have been reported in sheep and mice.
Transgenic sheep were produced by pronuclear microinjection with a mouse ultra-high-sulfur keratin promoter linked to an ovine insulin-like growth factor 1 (IGF1) cDNA. Five transgenic lambs resulted from the microinjection of 591 embryos; one male and one female showed IGF1 expression in the skin. A progeny test of the ram was carried out by matings to 43 non-transgenic ewes. Of 85 lambs born, 43 (50.6%) were transgenic. At yearling shearing (approximately 14 months of age), clean fleece weight was on average 6.2% greater in transgenic animals than in their non-transgenic half-sibs, with a greater effect in males (9.2%) than females (3.4%). Transgenics showed a small but significant increase in bulk, but male transgenics had a lower staple strength than female transgenics and non-transgenics which did not differ significantly. There were no significant differences in fiber diameter, medullation, and hogget body weight. To our knowledge this is the first reported improvement in a production trait by genetic engineering of a farm animal without adverse effects on health or reproduction.
Nearly 50 years ago, Chase published a review of hair cycling in which he detailed hair growth in the mouse and integrated hair biology with the biology of his day. In this review we have used Chase as our model and tried to put the adult hair follicle growth cycle in perspective. We have tried to sketch the adult hair follicle cycle, as we know it today and what needs to be known. Above all, we hope that this work will serve as an introduction to basic biologists who are looking for a defined biological system that illustrates many of the challenges of modern biology: cell differentiation, epithelial-mesenchymal interactions, stem cell biology, pattern formation, apoptosis, cell and organ growth cycles, and pigmentation. The most important theme in studying the cycling hair follicle is that the follicle is a regenerating system. By traversing the phases of the cycle (growth, regression, resting, shedding, then growth again), the follicle demonstrates the unusual ability to completely regenerate itself. The basis for this regeneration rests in the unique follicular epithelial and mesenchymal components and their interactions. Recently, some of the molecular signals making up these interactions have been defined. They involve gene families also found in other regenerating systems such as fibroblast growth factor, transforming growth factor-beta, Wnt pathway, Sonic hedgehog, neurotrophins, and homeobox. For the immediate future, our challenge is to define the molecular basis for hair follicle growth control, to regenerate a mature hair follicle in vitro from defined populations, and to offer real solutions to our patients' problems.
In order to investigate the effect of ascorbic acid (AsA) and ascorbic acid 2-phosphate (Asc 2-P), a long-acting vitamin C derivative, on the growth and differentiation of human osteoblast-like cells, we supplemented the culture medium of MG-63 cells with various concentrations (0.25 to 1 mM) of these factors. Asc 2-P significantly stimulated nascent cell growth at all concentrations in the presence of fetal bovine serum (FBS). On the other hand, AsA showed a growth repressive effect depending on its concentration, and that of FBS. Asc 2-P also increased expression of osteoblast differentiation markers, such as collagen synthesis and alkaline phosphatase (ALP) activity. These stimulative activities of Asc 2-P were attenuated by inhibitors of collagen synthesis, indicating that these effects were dependent on collagen synthesis. Electron micrographs of the cells showed the formation of a three-dimensional tissue-like structure endowed with a mature extracellular matrix in the presence of Asc 2-P.
Androgen significantly stimulates the proliferation of outer root sheath cells that are cocultured with beard dermal papilla cells without cell contact. The expression of insulin-like growth factor I (IGF-I) mRNA in beard dermal papilla cells was stimulated by androgen and antagonized by cyproterone acetate. Outer root sheath cells did not express mRNA for IGF-I either in the presence or absence of androgen. Both of these two types of cells expressed mRNA for IGF-I receptor and the expression was not affected by androgen. Neutralizing antibody against IGF-I antagonized the stimulatory effect of androgen on the growth of outer root sheath cell cocultured with beard dermal papilla cells. These findings suggest that IGF-I is a candidate for androgen induced hair growth factors.
Insulin stimulated hair follicle growth in a dose-dependent manner over the range of 0.01 to 100 micrograms/ml. Maximum rates of hair follicle growth were observed when follicles were maintained in medium containing 10 micrograms/ml insulin, which is supraphysiologic. Hair follicles maintained in the absence of insulin or at physiologic levels showed premature entry into a catagen-like state. Insulin-like growth factor (IGF)-I and -II had no significant effect on hair follicle growth when maintained in the presence of 10 micrograms/ml insulin. However, in the absence of insulin, both IGF-I (0.01-100 ng/ml) and IGF-II (0.01-100 ng/ml) stimulated hair follicle growth in a dose-dependent manner. IGF-I was more potent than either insulin or IGF-II, stimulating maximum rates of hair follicle growth at 10 ng/ml, whereas IGF-II gave maximum stimulation at 100 ng/ml. The rates of hair follicle growth stimulated by 10 ng/ml IGF-I were identical to those stimulated by 10 micrograms/ml insulin. IGF-II (100 ng/ml), however, was unable to stimulate hair follicle growth to the same extent as insulin. Both IGF-I (10 ng/ml) and IGF-II (100 ng/ml) were more potent than insulin at preventing hair follicles from entering into a catagen-like state. Growth hormone had no effect on hair follicle growth or morphology in the absence of insulin. These data suggest that in vitro IGF-I may be an important physiologic regulator of hair growth and possibly the hair growth cycle. Moreover, the removal of insulin from tissue culture medium may be a useful method of generating large numbers of catagen hair follicles for further in vitro studies.
Study of the involvement of the hair follicle papilla in hair growth regulation was greatly facilitated by the isolation and cultivation of this tiny cluster of fibroblast-like cells in the rat vibrissae and in the human hair follicle. While isolation of the hair follicle papilla from the former is relatively straightforward, the current method to isolate the much smaller human hair follicle requires significant skill. Thus, the routine initiation of primary cultures of human scalp hair follicle papilla cells requires significant training, time, and commitment.
In an attempt to simplify hair follicle papilla cell culture methodology for new laboratory personnel, we have made significant refinements to the current method. Our method requires only two simple manipulations to isolate hair follicle papilla from intact isolated hair follicles. This very rapid and easy method isolates clean and intact hair follicle papillae. Together with their attachment via scratching to the growth surface, the isolation and cultivation of this important hair follicle component can now be achieved easily by the laboratory newcomer. The method relies for its simplicity on the removal of the hair follicle papilla from the outside of the intact hair follicle rather than via internal manipulations from within the hair follicle.
In search of natural extracts for hair growth, we found that the extract of dried root of Sophora flavescens has outstanding hair growth promoting effect. After topical application of Sophora flavescens extract onto the back of C57BL/6 mice, the earlier conversion of telogen-to-anagen was induced. The growth of dermal papilla cells cultured in vitro, however, was not affected by Sophora flavescens extract treatment. RT-PCR analysis showed that Sophora flavescens extract induced mRNA levels of growth factors such as IGF-1 and KGF in dermal papilla cells, suggesting that the effects of Sophora flavescens extract on hair growth may be mediated through the regulation of growth factors in dermal papilla cells. In addition, the Sophora flavescens extract revealed to possess potent inhibitory effect on the type II 5alpha-reductase activity. Taken together, these results suggest that Sophora flavescens extract has hair growth promoting potential and can be used for hair growing products.
Epithelial-mesenchymal interactions play pivotal roles in the morphogenesis of many organs and various types of appendages. During hair follicle development, extensive interactions between two embryologically different hair follicle compartments (epidermal keratinocytes and dermal papilla fibroblasts) lead to the formation of the hair shaft-producing mini-organ that shows cyclic activity during postnatal life with periods of active growth, involution and resting. During the hair cycle, the epithelium and the mesenchyme are regulated by a distinct set of molecular signals that are unique for every distinct phase of the hair cycle. In telogen hair follicles, epithelial-mesenchymal interactions are characterized by a predominance of inhibitory signals that retain the hair follicle in a quiescent state. During anagen, a large variety of growth stimulatory pathways are activated in the epithelium and in the mesenchyme, the coordination of which are essential for proper hair fiber formation. During catagen, the termination of anagen-specific signaling interactions between the epithelium and the mesenchyme leads to apoptosis in the hair follicle epithelium, while activation of selected signaling pathways promotes the transition of the dermal papilla into a quiescent state. The signaling exchange between the follicular epithelium and the mesenchyme is modulated by proteoglycans, such as versican, which may significantly enhance or reduce the biological activities of secreted growth stimulators. However, additional research will be required to bridge the gap between our current understanding of mechanisms underlying epithelial-mesenchymal interactions in hair follicles and the potential clinical application of growth modulators involved in those interactions. Further progress in this area of research will hopefully lead to the development of new drugs for the treatment of hair growth disorders.