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Schematic diagram of this work. TRPC3 and NCX1 maintain dynamic calcium balance and participate in vascular activities under physiological conditions. However, upregulation of TRPC3 by high salt leads to intracellular Na + accumulation and then activated reverse mode of NCX1, which promotes sustained vasoconstriction caused by increased cytosolic calcium concentration. This might be an important reason for salt-sensitive hypertension. The antihypertensive effects of canagliflozin are mediated to decreasing cytosolic calcium concentration and vasoconstriction through inhibition of TRPC3. NCX1 indicates sodium-calcium exchanger 1; and TRPC3, transient receptor potential channels 3. Downloaded from http://ahajournals.org by on August 3, 2022
Source publication
Background
Salt‐sensitive hypertension is highly prevalent and associated with cardiorenal damage. Large clinical trials have demonstrated that SGLT2 (sodium‐glucose cotransporter 2) inhibitors exert hypotensive effect and cardiorenal protective benefits in patients with hypertension with and without diabetes. However, the underlying mechanism rema...
Context in source publication
Context 1
... results suggested that increased binding of TRPC3 on NCX1 facilitates the reverse mode switching of NCX1 that mediated the promotional effect of high salt on the vascular calcium handling. Canagliflozin antagonized HS-induced cytoplasmic calcium increase and vasoconstriction by reducing the binding of TRPC3 on rmNCX1 (Figure 7). ...
Citations
... 23 Furthermore, although the noninvasive tail-cuff methodology is well accepted for blood pressure monitoring in rats, this method also has some uncertainties because of the need for habituation to restrain and other influences on tail circulation. 24 Contrary to previous studies, 25 our data revealed that canagliflozin treatment significantly increased blood glucose levels in Dahl SS rats fed an HS diet for 12 weeks, which might be explained by the reduction in blood volume through natriuresis. The development of kidney dysfunction in HS diet-fed Dahl SS rats, including increased albumin, Scr, and FENa levels, was prevented by irbesartan and the combined treatment but not by canagliflozin alone. ...
Objectives
This study assessed the antifibrotic effects of canagliflozin, with or without irbesartan, on renal injury in Dahl salt-sensitive (SS) rats fed a high-salt (HS) diet.
Methods
After the preconditioning stage, Dahl SS rats (n = 47) were divided into five experimental groups as follows: low-salt (LS, n = 7), HS (n = 10), HS with canagliflozin (n = 10), HS with irbesartan (n = 10), and HS with canagliflozin and irbesartan (n = 10).
Results
The HS diet increased systolic blood pressure (SBP), renal fibrosis, fibrotic protein expression, and transforming growth factor-β1 (TGF-β1)/Smad2/3 pathway protein expression compared with the findings in the LS group. Irbesartan reduced SBP and slowed the loss of renal function. Canagliflozin significantly reduced body weight and renal fibrosis and suppressed the TGF-β1/Smad2/3 pathway. The combined therapy exerted better renoprotective effects on all outcome parameters.
Conclusions
These results indicate that canagliflozin and irbesartan exert different effects on renal injury in SS hypertensive rats, and the combined regimen could have stronger effects than either monotherapy.
... This effect was mitigated by treatment with the sodium-glucose cotransporter-2 inhibitor canagliflozin. 33 Furthermore, using proximity ligation assay it was shown that TRPC1 forms a complex with ORAI calcium release-activated calcium modulator 1 calcium voltage-gated channel subunit a1 C in VSMCs to induce Ca 2þ influx contributing to contraction. 34 These effects were observed in VSMCs from normal mice stimulated with serotonin or thapsigargin. ...
... The original data included 5892 proteins extracted from six experimental samples (Additional file 1: Table S1), of which 5875 proteins were retained after pretreatment (Additional file 2: Table S2). DEPs were screened according to the following criteria: P value < 0.05 and foldchange < 0.83 or > 1.2, as described in other studies [13][14][15][16] (Additional file 3: Table S3). The DEPs were subjected to GO enrichment [17] and KEGG pathway enrichment analyses [18]. ...
... A total of 5892 proteins were detected in these six samples, of which 5875 proteins remained after data filtering and normalization. Using differential protein expression analysis with the criteria of P value < 0.05 and fold-change < 0.83 or > 1.2, as used in other studies [13][14][15][16], we determined 383 DEPs, of which 258 were upregulated and 125 were downregulated ( Fig. 1c; Additional file 8: Table S8). Hierarchical cluster analysis showed that these 383 DEPs were separated into upregulated and downregulated clades, and that the Ant-1174 group was differentiated from the control group (Fig. 1d); thus, miR-1174 depletion substantially caused a global protein expression response in mosquitoes. ...
Background
Pathogenic viruses can be transmitted by female Aedes aegypti (Ae. aegypti) mosquitoes during blood-meal acquisition from vertebrates. Silencing of mosquito- and midgut-specific microRNA (miRNA) 1174 (miR-1174) impairs blood intake and increases mortality. Determining the identity of the proteins and metabolites that respond to miR-1174 depletion will increase our understanding of the molecular mechanisms of this miRNA in controlling blood-feeding and nutrient metabolism of mosquitoes.
Methods
Antisense oligonucleotides (antagomirs [Ant]) Ant-1174 and Ant-Ct were injected into female Ae. aegypti mosquitoes at 12–20 h posteclosion, and depletion of miR-1174 was confirmed by reverse transcription quantitative real-time PCR (RT-qPCR). Ant-1174-injected and control mosquitoes were collected before the blood meal at 72 h post-injection for tandem mass tag-based proteomic analysis and liquid chromatography-tandom mass spectrometry non-target metabolomic analysis to identify differentially expressed proteins and metabolites, respectively. RNA interference (RNAi) using double-stranded RNA (dsRNA) injection was applied to investigate the biological roles of these differentially expressed genes. The RNAi effect was verified by RT-qPCR and western blotting assays. Triglyceride content and ATP levels were measured using the appropriate assay kits, following the manufacturers’ instructions. Statistical analyses were conducted with GraphPad7 software using the Student’s t-test.
Results
Upon depletion of mosquito- and midgut-specific miR-1174, a total of 383 differentially expressed proteins (DEPs) were identified, among which 258 were upregulated and 125 were downregulated. Functional analysis of these DEPs using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment suggested that miR-1174 plays important regulatory roles in amino acid metabolism, nucleotide metabolism, fatty acid metabolism and sugar metabolism pathways. A total of 292 differential metabolites were identified, of which 141 were upregulated and 151 were downregulated. Integrative analysis showed that the associated differential proteins and metabolites were mainly enriched in a variety of metabolic pathways, including glycolysis, citrate cycle, oxidative phosphorylation and amino acid metabolism. Specifically, the gene of one upregulated protein in miR-1174-depleted mosquitoes, purine nucleoside phosphorylase (PNP; AAEL002269), was associated with the purine, pyrimidine and niacin-nicotinamide metabolism pathways. PNP knockdown seriously inhibited blood digestion and ovary development and increased adult mortality. Mechanically, PNP depletion led to a significant downregulation of the vitellogenin gene (Vg); in addition, some important genes in the ecdysone signaling and insulin-like peptide signaling pathways related to ovary development were affected.
Conclusions
This study demonstrates differential accumulation of proteins and metabolites in miR-1174-depleted Ae. aegypti mosquitoes using proteomic and metabolomic techniques. The results provide functional evidence for the role of the upregulated gene PNP in gut physiological activities. Our findings highlight key molecular changes in miR-1174-depleted Ae. aegypti mosquitoes and thus provide a basis and novel insights for increased understanding of the molecular mechanism involved in a lineage-specific miRNA in mosquito vectors.
Graphical Abstract
... 45 In Dahl SS rats on an excessive-sodium (4%) diet, dapagliflozin reduced BP and caused a left shift of the pressure-natriuresis curve (Figure 1), but it had no effect on the renin-angiotensin system or kidney sodium transporters, including NHE3 and the sodium-chloride cotransporter. 46 In another study using the same model, SGLT2 inhibitors reduced salt-induced vasoconstriction by inhibiting vascular cytoplasmic calcium increase; this effect was mediated by transient receptor potential channel 3 and sodium-calcium exchanger 1. 55 In addition to effects on kidney sodium transport and vascular tone, SGLT2 inhibitors may also exert their effects also by inhibiting the sympathetic nervous system. In a mouse model of neurogenic hypertension, chemical denervation reduced BP and SGLT2 protein expression. ...
High dietary sodium consumption is considered the most important modifiable lifestyle factor to prevent an increase in blood pressure and the development of hypertension. Despite numerous studies over the past decades, the pathophysiology explaining why some people show a salt-sensitive blood pressure response and others do not is incompletely understood. Here, a brief overview of the latest mechanistic insights is provided, focusing on the mononuclear phagocytic system and inflammation, the gut-kidney axis, and epigenetics. It also discusses the effects of 3 types of novel drugs on salt-sensitive hypertension: sodium-glucose cotransporter 2 inhibitors, non-steroidal MR antagonists, and aldosterone synthase inhibitors. The conclusion is that besides kidney-centered mechanisms, vasoconstrictor mechanisms are also relevant for both the understanding and treatment of this blood pressure phenotype.
... SGLT2i reduced intracellular Na + by directly docking at the late sodium channel (Nav1.5), inhibiting NHE influx, and reverse mode of NCX thereby decreasing intracellular Ca 2+ content in cardiomyocytes [39,44,45]. In the present study, we found that empagliflozin significantly decreases cytosolic Ca 2+ . ...
... TRP channels can be activated by PLC signaling [50,51]. A previous study revealed that SGLT2i decreases high salt-induced vasoconstriction through the inhibition of TRP channels [45]. SGLT2i can also decrease Ca 2+ overload through the L-type Ca 2+ channel (a kind of voltage-operated Ca 2+ channel) in cardiomyocytes [52]. ...
Background
The novel sodium-glucose co-transporter 2 inhibitor (SGLT2i) potentially ameliorates heart failure and reduces cardiac arrhythmia. Cardiac fibrosis plays a pivotal role in the pathophysiology of HF and atrial myopathy, but the effect of SGLT2i on fibrogenesis remains to be elucidated. This study investigated whether SGLT2i directly modulates fibroblast activities and its underlying mechanisms.
Methods and results
Migration, proliferation analyses, intracellular pH assay, intracellular inositol triphosphate (IP3) assay, Ca²⁺ fluorescence imaging, and Western blotting were applied to human atrial fibroblasts. Empagliflozin (an SGLT2i, 1, or 5 μmol/L) reduced migration capability and collagen type I, and III production. Compared with control cells, empagliflozin (1 μmol/L)- treated atrial fibroblasts exhibited lower endoplasmic reticulum (ER) Ca²⁺ leakage, Ca²⁺ entry, inositol trisphosphate (IP3), lower expression of phosphorylated phospholipase C (PLC), and lower intracellular pH. In the presence of cariporide (an Na⁺-H⁺ exchanger (NHE) inhibitor, 10 μmol/L), control and empagliflozin (1 μmol/L)-treated atrial fibroblasts revealed similar intracellular pH, ER Ca²⁺ leakage, Ca²⁺ entry, phosphorylated PLC, pro-collagen type I, type III protein expression, and migration capability. Moreover, empagliflozin (10 mg/kg/day orally for 28 consecutive days) significantly increased left ventricle systolic function, ß-hydroxybutyrate and decreased atrial fibrosis, in isoproterenol (100 mg/kg, subcutaneous injection)-induced HF rats.
Conclusions
By inhibiting NHE, empagliflozin decreases the expression of phosphorylated PLC and IP3 production, thereby reducing ER Ca²⁺ release, extracellular Ca²⁺ entry and the profibrotic activities of atrial fibroblasts.
... Kravtsova et al. showed that dapagliflozin treatment blunted the development of hypertension with increases in glucose and Na + excretion without secondary effects on the expression and function of other Na + transporters and channels along the nephron and systemic and intrarenal RAS in Dahl salt-sensitive hypertensive rats [44]. Zhao et al. showed that canagliflozin attenuated the development of hypertension by directly alleviating vasoconstriction in Dahl salt-sensitive hypertensive rats [45]. Saltinduced vascular transient receptor potential channel 3 upregulation resulted in augmented vasoconstriction in saltsensitive hypertensive rats by facilitating sodium-calcium exchanger 1-mediated vascular calcium uptake, which could be alleviated by canagliflozin. ...
... SIRT6 protects from vascular aging [35,36] SIRT6 protects from vascular calcificaƟon via Runx2 in CKD [37] Skin water conservaƟon by skin vasoconstricƟon causes hypertension [38] Rivaroxaban improves vascular inflammaƟon [41] Rivaroxaban aƩenuates cardiac remodeling aŌer myocardial infarcƟon [42] Rivaroxaban aƩenuates cardiac hypertrophy/fibrosis in hypertension [43] SGLT2i decreases BP in Dahl salt-sensiƟve rats [44,45] ...
The pathogenesis of hypertension is multifactorial and highly complex. Basic research plays critical roles in elucidating the complex pathogenesis of hypertension and developing its treatment. This review covers recent topics in basic research related to hypertension in the following six parts: brain/autonomic nervous system, kidney, vascular system, potential treatments, extracellular vesicles, and gut microbiota. The brain receives afferent nerve inputs from peripheral organs, including the heart, kidneys, and adipose tissue, and humoral inputs from circulating factors such as proinflammatory cytokines and leptin, which are involved in the regulation of central sympathetic outflow. In the kidneys, changes in Wnt/β-catenin signaling have been reported in several hypertensive models. New findings on the renin-angiotensin-aldosterone system in the kidneys have also been reported. Sirtuin 6, which participates in various cellular functions, including DNA repair, has been shown to have protective effects on the vascular system. Skin water conservation, mediated by skin vasoconstriction and the accumulation of osmolytes such as sodium, has been found to contribute to hypertension. Studies of rivaroxaban and sodium-glucose cotransporter-2 inhibitors as drug repositioning candidates have been performed. Extracellular vesicles have been shown to be involved in novel diagnostic approaches and treatments for hypertension as well as other diseases. In gut microbiota studies, interactions between microbiota and antihypertensive drugs and potential pathophysiology linking microbiota and COVID-19 have been reported. It can be seen that inter-organ communication has received particular attention from these recent research topics. To truly understand the pathogenesis of hypertension and to develop treatments for conquering hypertension, interresearcher communication and collaboration should be further facilitated. This mini-review focuses on recent topics on basic research in hypertension from the several points of view. The recent topics indicate that inter-organ communication has received particular attention. Interresearcher communication and collaboration should also be further facilitated to truly understand the complex pathogenesis of hypertension and to develop the treatments. This mini-review focuses on recent topics on basic research in hypertension from the several points of view. The recent topics indicate that inter-organ communication has received particular attention. Interresearcher communication and collaboration should also be further facilitated to truly understand the complex pathogenesis of hypertension and to develop the treatments. This mini-review focuses on recent topics on basic research in hypertension from the several points of view. The recent topics indicate that interorgan communication has received particular attention. Interresearcher communication and collaboration should also be further facilitated to truly understand the complex pathogenesis of hypertension and to develop the treatments.
... Contrary to previous studies [21], our data show that canagliflozin treatment significantly 156 ...
Hypertension is one of the major contributors to cardiovascular and chronic kidney disease (CKD). Sodium-glucose cotransporter 2 (SGLT2) inhibitors and angiotensin receptor blockers (ARBs) have become the preferred treatment for patients with CKD. However, the renoprotective effects of the combined therapy of the two drugs on hypertensive renal fibrosis are still largely understood. The aim of this study was to compare the antifibrotic effects of canagliflozin, with or without irbesartan, in the kidneys of Dahl salt-sensitive (Dahl SS) rats on a high salt (HS) diet. After the preconditioning stage, Dahl SS rats (n = 47) were divided into 5 experimental groups as follows: low salt control (n=7), HS control (n=10), high salt with canagliflozin (n=10), high salt with irbesartan (n=10), and high salt with canagliflozin plus irbesartan (n=10). Mean food and water intake, body weight (BW), and systolic blood pressure (SBP) were measured during the whole experimental period. After 12 weeks, the rats were euthanized, and the kidneys were excised for histomorphometric evaluation and immunohistochemical evaluation. An HS diet increased SBP, renal fibrosis, expression of fibrotic protein factors, and TGF-β/Smad2/3 pathway compared to the LS group. We found that irbesartan reduced SBP and slowed the loss of renal function. Canagliflozin significantly reduced BW and renal fibrosis and downregulated the TGF-β/Smad2/3 pathway. The combined therapy showed better renoprotection in all outcome parameters. In conclusion, these results indicate that canagliflozin and irbesartan exert different benefits on nephroprotection in salt-sensitive hypertensive rats.
... It's also notable that all these possible mechanisms of SGLT2i are not involved in any certain type of hypertension at the same time. For example, Zhao et al. found that Canagliflozin can improve vascular contraction and remodeling but not affect sympathetic nerve activity in Dahl salt-sensitive rats [33]. However, Lakshini et al. confirmed the inhibition effect on the sympathetic nervous system of dapagliflozin in BPH/2J mice [19]. ...
Review Role of Sodium Glucose Cotransporter 2 Inhibitor in Hypertension Zhitong Zhou, Dao Wen Wang, Junfang Wu * Division of Cardiology, Department of Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Hubei Key Laboratory of Genetics and Molecular Mechanisms of Cardiological Disorders, Wuhan 430030, China. * Correspondence: Junfang.wu@tjh.tjmu.edu.cn Received: 17 October 2022 Accepted: 15 November 2022 Published: 21 December 2022 Abstract: Sodium glucose cotransporter 2 inhibitors (SGLT-2i) are a new class of antidiabetic drugs that act by inhibiting the reabsorption of glucose in the proximal renal tubule, which results in lowering the level of blood and urinary glucose. Besides the glucose-lowing effect, some clinical trials found the benefits of SGLT2i in treating heart failure with or without diabetes. In 2021, SGLT2i were recommended by the European Society of Cardiology in treating of heart failure. Compared to heart failure, hypertension is a common cardiovascular disease with an increasing prevalence globally. There is also clinical evidence indicating that SGLT2i can lower blood pressure. Here we focused on addressing the role of SGLT-2i in treating hypertension and its possible mechanism in this review.
... The current issue of the Journal of the American Heart Association (JAHA) includes a study by Zhao et al that demonstrates the mechanisms underlying how SGLT2i canagliflozin improves hypertension in the Dahl salt-sensitive rat hypertensive model. 12 This study reveals TRPC3 as a salt-sensitive channel that interacts with NCX1 (sodium/ calcium exchanger 1) to modulate dysfunction of vascular calcium handling and hypertension, which is significantly improved by canagliflozin treatment. Although overexpression of TRPC3 mimicked the antihypertensive effects of canagliflozin, the TRPC3 knockout nullified these effects. ...
... Mechanistically, high salt-induced cytoplasmic calcium level and vasoconstriction, which required TRPC3, and this process could be blocked by canagliflozin. 12 They also revealed the novel mechanism of how canagliflozin improves endothelial function in vivo and in vitro. SGLT2i TRPC3 interaction would be a new therapeutic target, but direct mechanisms between SGLT2i and TRPC3 remain unknown. ...
... 19 These studies, along with the current study, suggest the protective effects of SGLT2i are beyond blood glucose regulation and enhanced diuretic effects. 12 Effects of SGLT2i may involve changes including myocardial and renal metabolism, and endothelial function. Importantly, these trials confirm the SGLT2i benefits on reduced hospitalized heart failure, cardiovascular death, and all-cause mortality in patients with heart failure with reduced ejection fraction, and renal composite outcomes. ...
