Si-Wu-Tang Alleviates Nonalcoholic Fatty Liver Disease via Blocking TLR4-JNK and Caspase-8-GSDMD Signaling Pathways.

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) has high global prevalence; however, the treatments of NAFLD are limited due to lack of approved drugs. METHODS: Mice were randomly assigned into three groups: Control group, NAFLD group, NAFLD plus Si-Wu-Tang group. A NAFLD mice model was established by feeding with a methionine- and choline-deficient (MCD) diet for four weeks. Si-Wu-Tang was given orally by gastric gavage at the beginning of 3rd week, and it lasted for two weeks. The treatment effects of Si-Wu-Tang were confirmed by examining the change of body weight, serum alanine aminotransferase (ALT) and aspartate transaminase (AST) levels, Oil Red O staining, and hematoxylin and eosin (H&E) staining of the liver samples and accompanied by steatosis grade scores. The expression and activation of the possible signaling proteins involved in the pathogenesis of NAFLD were determined by western blotting. RESULTS: Mice fed with four weeks of MCD diet displayed elevated serum levels of ALT and AST, while there was decreased body weight. The hepatic Oil Red O staining and H&E staining showed severe liver steatosis with high steatosis grade scores. All these can be improved by treating with Si-Wu-Tang for two weeks. Mechanistically, the increased hepatic TLR4 expression and its downstream JNK phosphorylation induced by MCD diet were suppressed by Si-Wu-Tang. Moreover, the upregulations of Caspase-8, gasdermin D (GSDMD), and cleaved-GSDMD in liver mediated by MCD diet were all inhibited by Si-Wu-Tang. CONCLUSIONS: Treatment with Si-Wu-Tang improves MCD diet-induced NAFLD in part via blocking TLR4-JNK and Caspase-8-GSDMD signaling pathways, suggesting that Si-Wu-Tang has potential for clinical application in treating NAFLD.

Icariin induces irisin/FNDC5 expression in C2C12 cells via the AMPK pathway.

Backgroud Icariin, a major bioactive pharmaceutical component of the Chinese herbal medicine Epimedii Herba, has demonstrated lipid-lowering and anti-obesity effects. Irisin/ fibronectin type III domain-containing 5 (FNDC5) protects against obesity by inducing browning in white adipose tissue. Objectives This study investigated the effects of icariin on irisin/FNDC5 expression in C2C12 myotubes. Method Cultured murine C2C12 myocytes were used to study the effects of icariin on irisin/FNDC5 expressions by Western-blot, qPCR, Elisa and Immunofluorescence. We also investigated FNDC5 expression in icariin-treated intact mice. Results Icariin increased irisin/FNDC5 protein levels. mRNA levels of irisin/FNDC5 were also increased in C2C12 myocytes after treatment with icariin. Icariin increased peroxisome proliferator-activated receptor gamma co-activator 1alpha (PGC-1α) protein and mRNA levels. Additionally, icariin exposure resulted in phosphorylation of AMP-activated protein kinase (AMPK) in a dose-dependent manner. The regulatory effect of icariin on FNDC5 protein expression was blocked by the AMPK antagonist compound C or silencing of AMPK, suggesting that icariin increased FNDC5 protein expression via the AMPK pathway. In vivo, icariin decreased body weight gain in C57BL/6 mice and increased FNDC5, PGC-1α, and p-AMPK expression levels in skeletal muscle. Conclusions Taken together, our results indicated that icariin induces irisin/FNDC5 expression via the AMPK pathway, indicating that icariin may be promising as an anti-obesity drug.

Curcumin Ameliorates Reserpine-Induced Gastrointestinal Mucosal Lesions Through Inhibiting IκB-α/NF-κB Pathway and Regulating Expression of Vasoactive Intestinal Peptide and Gastrin in Rats.

The objective of our study was to investigate whether curcumin protects against reserpine-induced gastrointestinal mucosal lesions (GMLs) in rats and to explore the mechanism of curcumin's action. Sprague-Dawley rats were randomly divided into four groups: control group, reserpine-treated group, reserpine treatment group with curcumin at high dose (200 mg/kg), and reserpine treatment group with curcumin at low dose (100 mg/kg). Rats in reserpine-treated group were induced by intraperitoneally administered reserpine (0.5 mg/kg) for 28 days. TUNEL staining and hematoxylin and eosin staining were used to evaluate the apoptotic cells and morphologic changes. In addition, to explore the mechanism of curcumin in protecting GMLs, we used serum of experimental rats to assess the level of vasoactive intestinal peptide (VIP), gastrin, interleukin-6, interleukin-10, tumor necrosis factor-α and interferon-γ by ELISA and radioimmunoassay. The protein levels of NF-κB, p-IκB-α, IκB-α, Bcl-2, Bax, and cleaved-caspase-3 were examined by western blot analysis. Data were analyzed with SPSS 19.0 software package. Curcumin treatment prevented tissue damage and cell death in the reserpine-treated rats and effectively decreased inflammatory response and balanced the expression of VIP and gastrin in the reserpine-treated rats. NF-κB, p-IκB-α, Bax, and cleaved-caspase-3 were increased in the reserpine group, but the curcumin high-dose group inhibited them. Curcumin can target the IκB-α/NF-κB pathway to inhibit inflammatory response and regulate the level of VIP and gastrin in reserpine-induced GML rats.

17ß-estradiol induces vasorelaxation by stimulating endothelial hydrogen sulfide release.

Estrogen exerts vascular protective effects, but the underlying mechanisms remain to be understood fully. In recent years, hydrogen sulfide (H(2)S) has increasingly been recognized as an important signaling molecule in the cardiovascular system. Vascular H(2)S is produced from L-cysteine, catalyzed by cystathionine γ-lyase (CSE). In our study, apolipoprotein E (ApoE)-deficient mice were ovariectomized and implanted with placebo (OVX mice) or 17ß-estradiol (E(2)) pellets (OVX + E(2) mice). Compared with OVX mice, OVX + E(2) mice showed increased plasma H(2)S levels (P = 0.012) and decreased aortic lesion area (P = 0.028). These effects were largely reversed when supplementing with the irreversible CSE inhibitor DL-propargylglycine (PPG) in the OVX + E(2) + PPG mice. Meanwhile, the nitric oxide and prostacyclin-resistant responses to cumulative application of acetylcholine (ACh) were studied among all the three groups of femoral arteries. Compared with the arteries in the OVX group, the vasodilator sensitivity of arteries to ACh was increased in the OVX + E(2) group and attenuated in the OVX + E(2) + PPG group. E(2) and estrogen receptor (ER) α agonist 4',4″,4'″-(4-propyl-[1H]-pyrazole-1,3,5-triyl) trisphenol rapidly increased H(2)S release in human endothelial cells, but not partially selective ERß agonist 2,3-bis-(4-hydroxyphenyl)-propionitrile. These effects were inhibited by ER antagonist ICI 182780 or by protein kinase G (PKG) inhibitor KT5823. Furthermore, endothelial PKG activity was increased by E(2) (P = 0.003) and E(2)-induced vasodilation was inhibited by KT5823 (P = 0.009). In conclusion, the endothelial CSE/H(2)S pathway is activated by E(2) through PKG, which leads to vasodilation. These actions may be relevant to estrogen's anti-atherogenic effect.

Common variation in with no-lysine kinase 1 (WNK1) and blood pressure responses to dietary sodium or potassium interventions- family-based association study.

BACKGROUND: Common variations in the gene with no-lysine kinase 1 (WNK1) are associated with hypertension, but because of gene-environment interaction, it is difficult to fully identify the genetic contribution of WNK1 gene polymorphism to blood pressure (BP) variability. The aim of this study was to identify the effect of common WNK1 variants on the shift of BP during strict dietary interventions of salt or potassium intake. METHODS AND RESULTS: A total of 342 subjects from 126 families were selected and sequentially maintained on normal diet for 3 days at baseline, a low-salt diet for 7 days (3g/day, NaCl), then a high-salt diet for 7 days (18 g/day), and high-salt diet with potassium supplementation for another 7 days (4.5 g/day, KCl). Five single nucleotide polymorphisms (SNPs) were selected from the WNK1 gene. rs880054 and rs12828016 were associated with diastolic BP (DBP) response during the low-or high-sodium intervention, and rs2301880 was significantly associated with systolic BP, DBP and mean arterial pressure responses to the high-sodium intervention (all P<0.05). Unfortunately, no associations for WNK1 SNPs and the constructed haplotype blocks of WNK1 with BP responses to high-salt-and-potassium supplement intervention reached nominal statistical significance. CONCLUSIONS: The WNK1 gene might be mechanistically involved in the variation in BP response to dietary sodium and potassium intake among individuals, and might contribute to the variation of this complex phenotype.

Potassium supplement ameliorates salt-induced haemostatic abnormalities in normotensive subjects.

BACKGROUND: Dietary high salt or low potassium is always associated with an increased incidence of death or cardiovascular complications, but the mechanisms remain elusive. We hypothesize that haemostatic abnormalities may play an important role in the phenomenon. METHODS: Twenty normotensive subjects (aged 25 to 50 years) were selected from a rural community of Northern China. All of the people were sequentially maintained on a 3-day baseline investigation, 7 days on a low-salt diet (51.3 mmol or 3 g of NaCI per day), 7 days on a high-salt diet (307.7 mmol or 18 g of NaCl per day), and another 7 days on a high-salt diet with potassium supplementation (4.5 g/day, KCI). The concentrations of fibrinogen, D-dimer and von Willebrand factor (vWF) in plasma were assessed, and these data represent the systemic haemostatic state. RESULTS: Plasma levels of fibrinogen, fibrin D-dimer and vWF were significantly higher in the high-salt diet than in the low-salt diet (P < 0.05). In contrast, potassium supplement could convert the sodium-dependent haemostatic abnormalities to normal (P < 0.05). CONCLUSIONS: Dietary high salt intake could stimulate the production of haemostatic factors, which may ultimately lead to cardiovascular events. Inversely, potassium supplementation could ameliorate the sodium-induced haemostatic abnormalities.

The role of caveolin1 and sprouty1 in genistein's regulation of vascular smooth muscle cell and endothelial cell proliferation.

Genistein prevents atherosclerosis by exerting protective effects on blood vessels. The aim of this study is to investigate the role of caveolin1 and sprouty1 in the regulation of proliferation of vascular smooth muscle cell (VSMC) and endothelial cell by genistein. Using thiazolyl blue tetrazolium bromide(MTT) and [3H]-TdR assay, we found genistein inhibited angiotensin II-induced proliferation in primary cultured VSMC while it stimulated proliferation of quiescent endothelial cells. The effects were attenuated by caveolin1 or sprouty1 siRNA. Western blot analysis indicated that genistein attenuated the phosphorylation of extracellular regulated kinase1/2(ERK1/2) in angiotensin II-induced proliferated VSMC but stimulated the phosphorylation of ERK1/2 in quiescent endothelial cell. Double staining immunofluorescence identified caveolin1 and sprouty1 coexpressed in the cytoplasm of both VSMC and endothelial cell. Genistein increased the expression of caveolin1, p-caveolin1 and sprouty1 in VSMC, while it had opposite effects in quiescent endothelial cell. Co-immunoprecipitation suggested that genistein exerted its effects through interaction of caveolin1 and sprouty1. Our results demonstrate that the inhibition of angiotensin II-induced proliferation of VSMC and stimulation of quiescent endothelial cell by genistein are regulated by caveolin1 and sprouty1, which are implemented through Ras/MAPK pathway.