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A. Chemical structure of quercetin, myricetin, kaempferol, and apigenin. The B-rings of quercetin and myricetin are catechol and pyrogallo respectively. B. Chemical structure of vitamin C or ascorbic acid.
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Eat more 'green' or eat 'five a day' is one of the most important healthy lifestyle behaviours in the 21 century. Aiming to fight cancer effectively, more than half patients use vitamins or herbs concurrently with conventional anticancer treatment. Flavonoids or polyphenols existing in vegetables, fruits and green tea are common plant pigments with...
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... There is conflicting or insufficient evidence to determine if drinking green tea increases the chances of developing some malignancies such as stomach cancer and non-melanoma skin cancers (Hou, 2013;Caini et al., 2017). Those taking boronic acid-based proteasome inhibitors, such as bortezomib (Velcade), for chemotherapy, should refrain from consuming green tea, because it interferes with these drugs (Jia and Liu (2013)). One cup of green tea per day was linked to a marginally lower risk of dying from cardiovascular causes, according to a meta-analysis of observational studies (Tang et al., 2015). ...
Background: Those who regularly drink black and green tea report positive effects such as lower blood sugar and cholesterol, increased intelligence, and better cardiovascular management, particularly for the elderly. However, younger people report normal agility that fades quickly along with accompanying headaches and discomforts like stomach bites and kidney pain, especially when taken over an extended period. Tea's anti-nutrient components are not disclosed on product labels during production. To inform consumers, our effort attempts to identify some of these phytochemical components and their relative proportions. Methodology: The established procedure of the Association of Official Analytical Chemists was followed to determine the phytochemical components of the tea sample both qualitatively and quantitatively. Results: The findings showed that green and black tea contained alkaloids, saponins, flavonoids, tannins, glycosides, nicotine, caffeine, and phenols, both qualitatively and quantitatively expressed in mg/g. In green tea and black tea respectively, the highest concentrations of flavonoids were 86.00±0.58 and 65.00±3.5, whereas the least concentrations of nicotine were 78.00±0.58 and 63.00±1.21. Green tea had more flavonoids than black tea, while black tea had more flavonoids overall. Conclusion: Given that both caffeine and nicotine are among the medications that people are advised against its consumption due to their potential health risks, the high concentrations of these substances in the tea samples suggested that they may be harmful to human health if consumed in excess. Customers of the two tea brands are cautioned to use their discretion, particularly about liver and kidney health.
... It has been reported that AA directly inactivates bortezomib activity by forming a tight but reversible complex through its vicinal diol group. 192 However, the dose used for this study was not pharmacological and it was in oral form. AA is also muted to be able to inactivate ixazomib because of the boronate moiety. ...
Introduction and aim. Over the past decades, the hypotheses that ascorbic acid (AA) can play a role as an
... However, intake of certain natural products and antioxidants such as vitamin C may interact with the MM medication bortezomib, hence antagonizing its effect. Therefore, it is wise to highlight the potential negative interactions between patients' anticancer therapies and complimentary therapies for MM patients in order to maximize the benefits of treatment [113]. ...
Multiple myeloma (MM) is a malignant hematological disease. The disease is characterized by the clonal proliferation of malignant plasma cells in the bone marrow. MM accounts for 1.3% of all malignancies and has been increasing in incidence all over the world. Various genetic abnormalities, mutations, and translocation, including epigenetic modifications, are known to contribute to the disease’s pathophysiology. The prognosis is good if detected early, or else the outcome is very bad if distant metastasis has already occurred. Conventional treatment with drugs poses a challenge when there is drug resistance. In the present review, we discuss multiple myeloma and its treatment, drug resistance, the molecular basis of epigenetic regulation, the role of natural products in epigenetic regulators, diet, physical activity, addiction, and environmental pollutants, which may be beneficial for clinicians and researchers.
... Being a tetrahydroxyflavoneand 7-hydroxyflavonol, it falls under flavonols family. It comes from kaempferol oxoanion as conjugate acid (Jia & Liu, 2013). ...
... OSCs possess anti-allergic, anti-inflammatory, antimicrobial, and antithrombotic activity (Souza et al., 2011;Yoshinari et al., 2012). Onions' bioactive compounds were reported to have many biological functions, such as antioxidant, antimicrobial, antiviral, anti-inflammatory, anticancer activity, antimutagenic activity, and defense of brain, liver, and heart (Ansari et al., 2009;Assefa et al., 2018;Beretta et al., 2017;Harwood et al., 2007;Jia & Liu, 2013;Quecan et al., 2019;Singh et al., 2009;Utesch et al., 2008). The important biological functions are categorized into in vitro and in vivo, and they have been described separately. ...
Bioactive compounds possess different health benefits. Onion contains various bioactive compounds, such as organosulfur compounds, flavonols, ascorbic acids, and carbohydrate prebiotics, and its by‐products have more content of flavonoids than the bulb. Diallyl monosulfide, diallyl disulfide, diallyl trisulfide, and diallyl tetrasulfide are the major organosulfur compounds, whereas quercetin, kaempferol, anthocyanin, and luteolin are considered as main flavonoids. Ascorbic acid and fructooligosaccharides are also regarded as bioactive compounds. Onion bioactive compounds have the strong antioxidant potential for neutralizing oxidative stress of the cells. These bioactive components are beneficial as anticarcinogenic, antibiotic, anti‐inflammatory, antiplatelet, antidiabetic, and cardioprotective agents along with other nutritional benefits. However, various postharvest practices have an impact on these bioactive compounds, for example, curing mostly enhances the bioactive level and processing temperature generally decreases the concentration of many of them, whereas storage studies suggest an increase of others under optimized conditions. Additionally, conventional extraction techniques showed a negative impact on bioactive compounds of onion, whereas innovative methods yielded a higher amount of bioactive components. There is a need for innovative and integrated procedures in the postharvest sector to maintain or enhance the level of bioactive compounds without compromising the quality of onions. The present review comprehensively describes different bioactive compounds of onion, their chemistry, and their pharmacotherapeutic roles. Moreover, it also explores the effects of various postharvest factors, such as temperature, storage duration, and extraction conditions on the level of the bioactive components. It also suggests industrial applications of onion waste and its bioactive compounds in the food sector.
... The designed nanomedicine also improved the pharmacokinetic effects of BTZ by decreasing its dose-related toxicities and unspecific protein binding due to the complexation between PCA and BTZ. Since the catechol group of PCA and the boronic acid functionality of BTZ are still conjugated under normal physiological pH (pH = 7.35), these BTZ related toxicities could be avoided, and only activated under acidic conditions that can be found in solid malignancies (Jia and Liu, 2013;Wang et al., 2017;Wang et al., 2018b). A salient feature of the boronic acid-catechol conjugate is that it is formed through dynamic covalent chemistry, and is reversible in a pHsensitive manner (Rowan et al., 2002). ...
The natural phenolic molecule caffeic acid, show promising effects on biological systems as an anti/pro-oxidant, anti-cancer, and anti-inflammatory agent. In nanoparticle functionalization designs, most organic nanoparticle coatings are utilized only for their ability to carry chemotherapeutics and targeting ligand. In this study, UV-light and auto-oxidation polymerization of caffeic acid on top of as-prepared gold nanoparticles was utilized to bring about a 5 nm multifunctional coating. The resulting polycaffeic acid (PCA) coating was used to conjugate both boronic acid containing compounds, chemotherapeutic bortezomib (BTZ) and cancer targeting ligand folate, while inducing mitochondrial reactive oxygen species that can damage intracellular proteins and DNA. This complements the drug payload, bortezomib’s cell survival inhibition properties. The drug, targeting ligand, and coating complexation are all pH cleavable under acidic pH condition (<5.0) which can be found in a tumor and endosomal microenvironment. The in vitro and in vivo experiments demonstrated cancer cytotoxicity and tumor inhibiting properties of the developed nanomedicine.
... This strategy can also answer the problem of BTZ inhibition of phenolic compounds from natural diet [23]. It has recently been discovered that dietary polyphenols can block BTZ activity by binding to the boronic acid functionality of the drug. ...
Phenolics from plant materials have garnered attention in nanomedicine research, due to their various medicinal properties. Caffeic acid, a phenolic compound that is abundant in coffee beans, has been proven to have anticancer effects, due to its reactive oxygen species (ROS)-inducing properties. Here, a supramolecular nanomedicine was designed using caffeic acid molecule and the synthetic anticancer drug bortezomib, via catechol–boronic acid conjugation and Fe(III) ion crosslinking. Bortezomib is a proteasome-inhibiting drug and its boronic acid functional group can bind to caffeic acid’s catechol moiety. By having a nanoparticle formulation that can deliver bortezomib via intracellular endocytosis, the catechol–boronic acid conjugation can be dissociated, which liberates the boronic acid functional group to bind to the 26S proteasome of the cell. The ROS-inducing property of caffeic acid also complements the bortezomib payload, as the latter suppresses the survival mechanism of the cell through NF-κB inhibition.
... The efficacy of boron-containing drugs may also be affected by diet, and metabolism. For example, flavonoids, which are found in green tea, fruits, vegetables and wine, can react with boronic acids to form esters, which can affect drug properties, as in the case of Bortezomib [57]. Importantly, there is relatively limited structure-activity-relationship information on (bi)cyclic boronates, especially compared to the long history of such studies with b-lactams. ...
The β-lactams remain the most important antibacterials, but their use is increasingly compromised by resistance, importantly by β-lactamases. Although β-lactam and non-β-lactam inhibitors forming stable acyl-enzyme complexes with nucleophilic serine β-lactamases (SBLs) are widely used, these are increasingly susceptible to evolved SBLs and do not inhibit metallo-β-lactamases (MBLs). Boronic acids and boronate esters, especially cyclic ones, can potently inhibit both SBLs and MBLs. Vaborbactam, a monocyclic boronate, is approved for clinical use, but its β-lactamase coverage is limited. Bicyclic boronates rapidly react with SBLs and MBLs forming stable enzyme-inhibitor complexes that mimic the common anionic high-energy tetrahedral intermediates in SBL/MBL catalysis, as revealed by crystallography. The ability of boronic acids to 'morph' between sp2 and sp3 hybridisation states may help enable potent inhibition. There is limited structure-activity relationship information on the (bi)cyclic boronate inhibitors compared to β-lactams, hence scope for creativity towards new boron-based β-lactamase inhibitors/antibacterials.
... Some flavonoids, e.g. quercetin and myricetin, can inhibit the action of bortezomib through the reaction with the boronic acid -B(OH) 2 group of bortezomib by forming cyclic boronate esters with pyrogallol and catecholic groups of the flavonoids [143,144] (Fig. 9). From the onset, it was assumed that the antagonistic activity of phenolic compounds against bortezomib is related to their antioxidant activity. ...
... The authors suggest that the presence of catechol and pyrogallol in plasma may negatively affect the pro-apoptotic activity of bortezomib [144]. The compounds containing catechol/pyrocatechol structures include, but are not limited to, quercetin, catechin, epicatechin, rutin, luteolin, caffeic acid, cyanidin, while among the polyphenols containing pyrogallol structures are: mirycetin, gallic acid, epigallocatechin, tannin and delphinidin [143]. It is worth noting that concentrations of polyphenols that are found in human plasma while maintaining a normal diet are sufficient to significantly inhibit the activity of bortezomib [146] (see Fig. 11 U251). ...
... It is worth noting that concentrations of polyphenols that are found in human plasma while maintaining a normal diet are sufficient to significantly inhibit the activity of bortezomib [146] (see Fig. 11 U251). A similar effect was demonstrated by EGC (epigallatecatechin), ECG (epicatechingallate) and EC (epicatechin), green tea components containing the 1,2-benzenediol moiety in their structure [143,148]. The antagonistic effect was not observed for PIs other than boronic acid (MG-132, PSeI, nelfinavir) [148]. ...
... These showed strong antioxidant properties and considered acting as cancer-preventing or anticancer agents. [41] Anthocyanins show inhibitory effects on the growth of some cancer cells. ...
... Most leafy vegetable, fruits, and green pods contain a high amount of these pigments; hence, these are utilized as green. [41] Besides, pigments fresh fruits also found rich in vitamins which also assist in conventional anticancer treatment. In addition, specific anthocyanin metabolites showed additive and synergistic efficacy. ...
Present review article explains the dietary use of plant pigments and therapeutic effects against cancer. Important plant pigments such as anthocyanins, lycopene, carotenoids, chlorophyll, and betalains are explained for their anticancer effects. Plant pigments are secondary metabolites which obstruct cancer cell proliferation; stop growth and cell division in cancer cells. These inhibit cellular processes in cancer cells such as signaling pathways, cell cycle, induce apoptosis, and autophagy. Besides, anticancer activity these also assist in controlling high blood pressure, obesity, hyperglycemia, hypercholesterolemia, and restore cardiovascular problems. A full series of pigments is available in various plants families which might show protective effects against cancer. Plant pigments are edible, nutritionally rich and therapeutically suitable. Due to their health-promoting effects there is a growing public interest to consume green vegetables, fruits, sprouted seeds, pigmented cereals, and processed low energy antioxidative functional food. For widening their use, these could be harvested using recombinant gene technology to add to processed foods as a coloring agent. Plant pigments as natural plant products or its by-products are highly useful for the development of a large variety of functional foods, digestive ingredients, additives, as well as cosmetic products. These could be naturally added to genetically suitable modified foods by applying genomic tools. No doubt plant secondary metabolites will also fulfill needs of present-day medicine and show great promise for the future.
... Unexpectedly, PGG treatment has an antagonist effect against bortezomib's growth-inhibiting activity in all tested MM cell lines. Recently, increasing reports found that a vicinal diol group containing natural compounds or antioxidants present in green leaves and green teas can chemically interact with bortezomib and neutralize the effect of bortezomib-mediated cell growth (Jia and Liu, 2013). Because, PGG is a vicinal diol containing natural compound, therefore, the antagonistic effect of PGG on bortezomib might be attributed to its metaphenolic moieties. ...
Multiple myeloma (MM) still remains an incurable disease, therefore discovery of novel drugs boosts the therapeutics for MM. The natural compound 1,2,3,4,6-Penta-O-galloyl-beta-D-glucopyranoside (PGG) has been shown to exhibit antitumor activities against various cancer cells. Here, we aim to evaluate antitumor effects of PGG on MM cell lines. PGG inhibited the growth of three different MM cell lines in a dose- and time-dependent manner. Cell cycle analysis revealed that PGG treatment caused cell cycle arrest in G1 phase. It also induced apoptosis which was indicated by significant increases of Annexin V positive cells, caspase 3/7 activity, and cleaved caspase 3 expression in PGG treated MM cell. Since MYC is frequently hyperactivated in MM and inhibition of MYC leads to MM cell death. We further demonstrated that PGG decreased MYC expression in protein and mRNA levels and reversed the mRNA expression of MYC target genes such as p21, p27, and cyclin D2. In addition, PGG also reduced protein expression of DEPTOR which is commonly overexpressed in MM. Unexpectedly, PGG antagonized the cytotoxic effect of bortezomib in the combination treatment. However, PGG treatment sensitized MM cells to another proteasome inhibitor MG132 induced cytotoxicity. Moreover, MYC inhibitor JQ1 enhanced the cytotoxic effect of bortezomib on MM cells. Our findings raised concerns about the combinatory use of bortezomib with particular types of chemicals. The evidence also provide useful insights into the combination of MYC and proteasome-inhibitors for MM therapy. Finally, PGG has a therapeutic potential for treatment of MM and further development is mandatory.
