Puerarin attenuates high-glucose and diabetes-induced vascular smooth muscle cell proliferation by blocking PKCβ2/Rac1-dependent signaling
ABSTRACT Oxidative stress has been implicated in several steps leading to the development of diabetic vascular complications. The purpose of this study was to determine the efficacy and the possible mechanism of puerarin on high-glucose (HG; 25 mM)-induced proliferation of cultured rat vascular smooth muscle cells (VSMCs) and neointimal formation in a carotid arterial balloon injury model of obese Zucker rats. Our data demonstrated that puerarin significantly inhibited rat VSMC proliferation as well as reactive oxygen species (ROS) generation and NADPH oxidase activity induced by HG treatment. Further studies revealed that HG treatment resulted in phosphorylation and membrane translocation of PKCbeta2 as well as Rac1, p47phox, and p67phox subunits, leading to NADPH oxidase activation. Puerarin treatment remarkably disrupted the phosphorylation and membrane translocation of PKCbeta2 as well as Rac1, p47phox, and p67phox subunits. Blocking PKCbeta2 by infection with AdDNPKCbeta2 also abolished HG-induced phosphorylation and membrane translocation of Rac1, p47phox, and p67phox subunits as well as ROS production and NADPH oxidase activation in VSMCs. In vivo neointimal formation of obese Zucker rats evoked by balloon injury was evidently attenuated by the administration of puerarin. These results demonstrate that puerarin may exert inhibitory effects on HG-induced VSMC proliferation via interfering with PKCbeta2/Rac1-dependent ROS pathways, thus resulting in the attenuation of neointimal formation in the context of hyperglycemia in diabetes mellitus.
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- "Benth. (Leguminosae) may exert inhibitory effects on high glucose-induced vascular smooth muscle cell proliferation via interfering with PKCβ2/Rac1-dependent ROS pathways, thus resulting in the attenuation of neointimal formation in the context of hyperglycemia in diabetes mellitus. Hirudomedicinalis has been proved to have markedly improvement effect on blood viscosity, which might also involved in the increase of pancreatic blood flow induced by PRD. "
ABSTRACT: The islet vascular system is critical for β-cell function. This study investigated the antidiabetic effect of the Chinese Pu-Ren-Dan (PRD) recipe by regulating the pancreatic angiogenic factors in T2DM rats. High fat diet/streptozotocin-induced obese type-2 diabetes mellitus rats were developed and treated with PRD for 4 weeks. Then glucolipid metabolism, insulin secretion, pancreatic blood flow, ultrastructure of islet β-cell, histological changes of islet and protein expressions of pancreatic angiogenic factors were investigated. PRD-reduced T2DM rats' body weight and blood glucose level resisted the lipid metabolism disturbance, and ameliorated the insulin resistance and β-cell function. In addition, the histological and morphological studies proved that PRD could maintain the normal distribution of endocrine cell in islet and normal ultrastructure of β cell. An increased pancreatic blood flow was observed after the PRD treatment. In the investigation of pancreatic angiogenic factors, PRD inhibited the decreased expression of VEGF and Ang-1, and reversed the reduction of VEGFR2 and Tie2 phosphorylation in T2DM rats; the Ang-2 and TGFβ expression were up-regulated by PRD while PKC was activated; endostatin and angiostatin were down-regulated by PRD. The results suggest that increasing VEGF expression, regulating VEGF/VEGFR2 signaling, stimulating Ang-1/Tie-2 signaling pathway, and inhibiting PKC-TGFβ signaling and antiangiogenic factors might be the underlying mechanism of PRD's antidiabetic effect.Indian Journal of Pharmacology 03/2013; 45(6):556-562. DOI:10.4103/0253-7613.121364 · 0.69 Impact Factor
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- "Rat VSMCs were isolated enzymatically from the thoracic aortas of Sprague-Dawley rats. These cells were cultured in DMEM/F12 medium containing 10% fetal bovine serum and were identified as VSMCs by smooth muscle-α-actin (SMA) immunostaining, as previously described (12,13). VSMCs were grown to 60–80% confluence and were serum-starved for 24 h. "
ABSTRACT: Vascular smooth muscle cell (VSMC) proliferation plays a critical role in the development of vascular diseases. In the present study, we tested the efficacy and the mechanisms of action of gastrodin, a bioactive component of the Chinese herb Gastrodia elata Bl, in relation to platelet-derived growth factor-BB (PDGF-BB)-dependent cell proliferation and neointima formation after acute vascular injury. Cell experiments were performed with VSMCs isolated from rat aortas. WST and BrdU incorporation assays were used to evaluate VSMC proliferation. Eight-week-old C57BL/6 mice were used for the animal experiments. Gastrodin (150 mg/kg/day) was administered in the animal chow for 14 days, and the mice were subjected to wire injury of the left carotid artery. Our data demonstrated that gastrodin attenuated the VSMC proliferation induced by PDGF-BB, as assessed by WST assay and BrdU incorporation. Gastrodin influenced the S-phase entry of VSMCs and stabilised p27Kip1 expression. In addition, pre-incubation with sinomenine prior to PDGF-BB stimulation led to increased smooth muscle-specific gene expression, thereby inhibiting VSMC dedifferentiation. Gastrodin treatment also reduced the intimal area and the number of PCNA-positive cells. Furthermore, PDGF-BB-induced phosphorylation of ERK1/2, p38 MAPK, Akt and GSK3β was suppressed by gastrodin. Our results suggest that gastrodin can inhibit VSMC proliferation and attenuate neointimal hyperplasia in response to vascular injury. Furthermore, the ERK1/2, p38 MAPK and Akt/GSK3β signalling pathways were found to be involved in the effects of gastrodin.International Journal of Molecular Medicine 08/2012; 30(5):1034-40. DOI:10.3892/ijmm.2012.1100 · 2.09 Impact Factor
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- "Many reports have demonstrated that puerarin possesses a lot of activities including antioxidative activity (Guerra et al., 2000; Han et al., 2007), antiinflammation (Kim et al., 2010; Singh et al., 2007; Yang et al., 2010; Zheng et al., 2009) and anti-apoptosis (Bo et al., 2005; Mercer et al., 2005; Xiong et al., 2006; Zheng and Xu, 2007). Administration of puerarin has been reported to protect cardiovascular system by decreasing the levels of oxidative stress markers as well as by increasing the antioxidant cascade (Lu et al., 2009; Zhu et al., 2010). Increasing evidence shows that puerarin can protect kidney from injury induced by nephrotoxins (Li et al., 2009; Liu et al., 2010a,b; Shen et al., 2009). "
ABSTRACT: Puerarin (PU), a natural flavonoid, has been reported to have many benefits and medicinal properties. However, its protective effects against lead (Pb) induced injury in kidney have not been clarified. The aim of the present study was to investigate the effects of puerarin on renal oxidative stress and apoptosis in rats exposed to Pb. Wistar rats were exposed to lead acetate in the drinking water (500mg Pb/l) with or without puerarin co-administration (100, 200, 300 and 400mg PU/kg intragastrically once daily) for 75days. Our data showed that puerarin significantly prevented Pb-induced nephrotoxicity in a dose-dependent manner, indicated by both diagnostic indicators of kidney damage (serum urea, uric acid and creatinine) and histopathological analysis. Moreover, Pb-induced profound elevation of reactive oxygen species (ROS) production and oxidative stress, as evidenced by increasing of lipid peroxidation level and depleting of intracellular reduced glutathione (GSH) level in kidney, were suppressed by treatment with puerarin. Furthermore, TUNEL assay showed that Pb-induced apoptosis in rat kidney was significantly inhibited by puerarin. In exploring the underlying mechanisms of puerarin action, we found that activities of caspase-3 were markedly inhibited by the treatment of puerarin in the kidney of Pb-treated rats. Puerarin increased phosphorylated Akt, phosphorylated eNOS and NO levels in kidney, which in turn inactivated pro-apoptotic signaling events including inhibition of mitochondria cytochrome c release and restoration of the balance between pro- and anti-apoptotic Bcl-2 proteins in kidney of Pb-treated rats. In conclusion, these results suggested that the inhibition of Pb-induced apoptosis by puerarin is due at least in part to its antioxidant activity and its ability to modulate the PI3K/Akt/eNOS signaling pathway.Toxicology and Applied Pharmacology 12/2011; 258(3):330-42. DOI:10.1016/j.taap.2011.11.015 · 3.71 Impact Factor