Cinnamaldehyde Ameliorates Vascular Dysfunction in Diabetic Mice by Activating Nrf2.

BACKGROUND: Oxidative stress is known to be associated with the development of diabetes. Cinnamaldehyde (CA) is a spice compound in cinnamon that enhances the antioxidant defense against reactive oxygen species (ROS) by activating nuclear factor erythroid-related factor 2 (Nrf2), which has been shown to have a cardioprotection effect. However, the relationship between CA and Nrf2 in diabetic vascular complications remains unclear. METHODS: Leptin receptor-deficient (db/db) mice were fed normal chow or diet containing 0.02% CA for 12 weeks. The vascular tone, blood pressure, superoxide level, nitric oxide (NO) production, renal morphology, and function were measured in each group. RESULTS: CA remarkably inhibited ROS generation, preserved NO production, increased phosphorylated endothelial nitric oxide synthase (p-eNOS), attenuated the upregulation of nitrotyrosine, P22 and P47 in aortas of db/db mice, and apparently ameliorated the elevation of type IV collagen, TGF-ß1, P22, and P47 in kidney of db/db mice. Feeding with CA improved endothelium-dependent relaxation of aortas and mesenteric arteries, and alleviated the remodeling of mesenteric arteries in db/db mice. Additionally, dietary CA ameliorated glomerular fibrosis and renal dysfunction in diabetic mice. Nrf2 and its targeted genes heme oxygenase-1 (HO-1) and quinone oxidoreductase-1 (NQO-1) were slightly increased in db/db mice and further upregulated by CA. However, these protective effects of CA were reversed in Nrf2 downregulation mice. CONCLUSIONS: A prolonged diet of CA protects against diabetic vascular dysfunction by inhibiting oxidative stress through activating of Nrf2 signaling pathway in db/db mice.

Tiaopi huxin recipe improved endothelial dysfunction and attenuated atherosclerosis by decreasing the expression of caveolin-1 in ApoE-deficient mice.

The Tiaopi Huxin recipe (TPHXR) is widely used in traditional Chinese medicine for the clinical treatment of coronary heart disease. However, the mechanism of TPHXR treatment of atherosclerosis (AS) has not been fully elucidated. In this study, we have aimed to explore the potential antiatherosclerotic effect of TPHXR and its underlying mechanisms. Male ApoE knockout (ApoE-/- ) mice were fed a high-fat diet for 12 weeks and were randomly divided into four groups: the control group, and the low-dose, medium-dose, and high-dose TPHXR groups. The nitric oxide (NO) levels in arterial tissue and human umbilical vein endothelial cells (HUVECs) were measured by diaminofluorescein-2 diacetate staining. Vasorelaxation of mice aorta was performed by wire myograph. Inflammatory cytokines, including tumor necrosis factor-α (TNF-α), hs-CRP, IL-6, and IL-1ß, in mice plasma were analyzed by enzyme-linked immunosorbent assay. Western blot analysis was applied to observe protein expression. Oil Red O staining was utilized for the quantification of atherosclerotic plaques. Results showed that 4 weeks of high- and medium-dose TPHXR treatment by oral gavage reduced atheromatous lesions in ApoE -/- mice. The high- and medium-dose TPHXR treatment, but not the low-dose treatment, promoted eNOS phosphorylation, increased NO levels and improved endothelium-dependent vasorelaxation in ApoE -/- mice. High- and medium-dose TPHXR, but not low-dose TPHXR, decreased the expression of cav-1, NF-κB p50, NF-κB p65, ICAM1, VCAM-1, TNF-α, IL-6, and IL-1ß in the vasculature of ApoE -/- mice. Enzyme-linked immunosorbent assay analysis indicated that high- and medium-dose TPHXR decreased the levels of TNF-α, IL-6, hs-CRP, and IL-1ß. In conclusion, our findings show that TPHXR improved the endothelial function and reduced atheromatous lesions in ApoE -/- mice. This result may be due to the decreased expression of caveolin-1 and NF-κB and, hence, the attenuated inflammatory response in AS mice vasculature. TPHXR may represent a promising intervention in patients with AS.

Salvianolic Acid B Ameliorates Hyperglycemia and Dyslipidemia in db/db Mice through the AMPK Pathway.

BACKGROUND/AIMS: Salvianolic acid B (Sal B), a major polyphenolic compound of Salvia miltiorrhiza Bunge, has been shown to possess potential antidiabetic activities. However, the action mechanism of SalB in type 2 diabetes has not been investigated extensively. The present study was designed to investigate the effects of Sal B on diabetes-related metabolic changes in a spontaneous model of type 2 diabetes, as well as its potential molecular mechanism. METHODS: Male C57BL/KsJ-db/db mice were orally treated with Sal B (50 and 100 mg/kg) or metformin (positive drug, 300 mg/kg) for 6 weeks. RESULTS: Both doses of Sal B significantly decreased fasting blood glucose, serum insulin, triglyceride and free fatty acid levels, reduced hepatic gluconeogenic gene expression and improved insulin intolerance in db/db mice. High dose Sal B also significantly improved glucose intolerance, increased hepatic glycolytic gene expression and muscle glycogen content, and ameliorated histopathological alterations of pancreas, similar to metformin. Sal B treatment resulted in increased phosphorylated AMP-activated protein kinase (p-AMPK) protein expression in skeletal muscle and liver, increased glucose transporter 4 (GLUT4) and glycogen synthase protein expressions in skeletal muscle, and increased peroxisome proliferator-activated receptor alpha (PPARα) and phosphorylated acetyl CoA carboxylase (p-ACC) protein expressions in liver. CONCLUSION: Our data suggest that Sal B displays beneficial effects in the prevention and treatment of type 2 diabetes at least in part via modulation of the AMPK pathway.

Biological activities of salvianolic acid B from Salvia miltiorrhiza on type 2 diabetes induced by high-fat diet and streptozotocin.

CONTEXT: Salvia miltiorrhiza Bge. (Labiatae) has been widely used for treating diabetes for centuries. Salvianolic acid B (SalB) is the main bioactive component in Salvia miltiorrhiza; however, its antidiabetic activity and possible mechanism are not yet clear. OBJECTIVE: To investigate the effects of SalB on glycometabolism, lipid metabolism, insulin resistance, oxidative stress, and glycogen synthesis in type 2 diabetic rat model. MATERIALS AND METHODS: High-fat diet (HFD) and streptozotocin-induced diabetic rats were randomly divided into model group, SalB subgroups (50, 100, and 200 mg/kg), and rosiglitazone group. RESULTS: Compared with the model group, SalB (100 and 200 mg/kg) significantly decreased blood glucose (by 23.8 and 21.7%; p < 0.05 and p < 0.01) and insulin (by 31.3 and 26.6%; p < 0.05), and increased insulin sensitivity index (by 10.9 and 9.3%; p < 0.05). They also significantly decreased total cholesterol (by 24.9 and 27.9%; p < 0.01), low-density lipoprotein cholesterol (by 56.2 and 64.6%; p < 0.01), non-esterified fatty acids (by 32.1 and 37.9%; p < 0.01), hepatic glycogen (by 41.3 and 60.5%; p < 0.01), and muscle glycogen (by 33.2 and 38.6%; p < 0.05), and increased high-density lipoprotein cholesterol (by 50.0 and 61.4%; p < 0.05 and p < 0.01), which were originally altered by HFD and streptozotocin. In addition, SalB (200 mg/kg) markedly decreased triglyceride and malondialdehyde (by 31.5 and 29.0%; p < 0.05 and p < 0.01), and increased superoxide dismutase (by 56.6%; p < 0.01), which were originally altered by HFD and streptozotocin. DISCUSSION AND CONCLUSION: The results indicate that SalB can inhibit symptoms of diabetes mellitus in rats and these effects may partially be correlated with its insulin sensitivity, glycogen synthesis and antioxidant activities.

Salvianolic acid B inhibited PPARγ expression and attenuated weight gain in mice with high-fat diet-induced obesity.

BACKGROUND/AIMS: Obesity contributes to the development of cardiometabolic disorders such as type 2 diabetes, fatty liver disease and cardiovascular disease. Salvianolic acid B (Sal B) is a molecule derived from the root of Salvia miltiorrhiza (Danshen), which is a traditional Chinese medicine that is widely used to treat cardiovascular diseases. However, the role of Sal B in obesity and obesity-related metabolic disorders is unknown. In this study, we aimed to investigate the effects of Sal B on high-fat diet-induced obesity and determine the possible mechanisms involved. METHODS: Male C57BL/6J mice fed a high-fat diet for 12 weeks received a supplement of Sal B (100 mg/kg/day) by gavage for a further 8 weeks. These mice were compared to control mice fed an un-supplemented high-fat diet. 3T3-L1 preadipocytes were used in vitro studies. RESULTS: Sal B administration significantly decreased body weight, white adipose tissue weight, adipocyte size and lipid (triglyceride and total cholesterol) levels in obese mice. Eight weeks of Sal B administration also improved the intraperitoneal glucose tolerance test (IPGTT) and intraperitoneal insulin tolerance test (IPITT) scores in high-fat diet-induced obese mice. In 3T3-L1 preadipocytes that were cultured in vitro and induced to differentiate, Sal B reduced the accumulation of lipid droplets and lipid content in a dose-dependent manner. Immunoblotting indicated that Sal B decreased peroxisome proliferator-activated receptor gamma (PPARγ) and CCAAT/enhancer binding protein α (C/EBPα) expression but increased the expression of GATA binding protein 2 and 3 (GATA 2, GATA 3) both in vivo and in vitro. CONCLUSION: Our data suggest that Sal B may reduce obesity and obesity-related metabolic disorders by suppressing adipogenesis. The effects of Sal B in adipose tissue may be related to its action on PPARγ, C/EBPα, GATA-2 and GATA-3.

[The empirical study of Maxingganshi decoction and its compatibility in acute lung injury rats].

OBJECTIVE: To explore the pharmacodyniamic action and the mechanism of action of the Maxingganshi decoction in acute lung injury rats in order to supply the pharmacology evidence to cure the SIRS-ALI of Maxingganshi decoction. METHODS: The study designed by orthogonal design. The SIRS-ALI model were Conseructed by the LPS intravenous injection and the effects of Maxingganshi decoction and it's different compatibilities to the SIRS-ALI model were observed. The experiments results were analvsised in order to reveal the compatibility rules of the Maxingganshi decocotion. RESULTS: Maxingganshi decocotion and its different compatibilities had good effects of prevention and cure the SIRS-ALI. The mechanism maybe concerned with the Maxingganshi decocotion can decrease the TNF-alpha and increase the IL-10. The experiments results also indicated that the action of the full formula was the best. The principal drug was the most important in the formula. CONCLUSION: Maxingganshitang has a good effect in anti the ALI; the results indicat that the principal drug is the predominant therapeutic action in the formula ministerial drug. Adjuvant drug and messenger drug can strengthen pharmacodynamic action.

[Influence of compatibility on content of berberine in Maxingganshi decoction].

OBJECTIVE: To set up the quantitative method of herberine in decoctions prepared from various combinations of Maxingganshi decotion by HPLC and to determine the change of general contents in different decoction. METHODS: The study was designed by L8 (2(7)) orthogonal and to determine the change of general contents in different decoction by HPLC. RESULTS: In full formula remove Glycyrrhiza uralensis group, the contents of L-ephedrine, d-pseudephedrine and the amygdaloside cut down significantly. In full formula remove armeniacae semen group, the content of glycyrrhetic acid cut down significantly. Four chemical composition in full formula group had higher contents. CONCLUSION: Armeniacae semen can decrease the content of L-ephedrine, D-pseudephedrine. Glycyrrhiza uralensis can help decoctum amygdaloside and armeniacae semen can help decoctum glycyrrhizic acid.