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Medicine of the, United Kingdom

Yang X.-Y.,Peking University | He K.,Peking University | Pan C.-S.,Peking University | Li Q.,Peking University | And 16 more authors.
Scientific Reports | Year: 2015

The present study aimed to detect the role of 3, 4-dihydroxyl-phenyl lactic acid (DLA) during ischemia/reperfusion (I/R) induced myocardial injury with emphasis on the underlying mechanism of DLA antioxidant. Male Spragu-Dawley (SD) rats were subjected to left descending artery occlusion followed by reperfusion. Treatment with DLA ameliorated myocardial structure and function disorder, blunted the impairment of Complex I activity and mitochondrial function after I/R. The results of 2-D fluorescence difference gel electrophoresis revealed that DLA prevented the decrease in NDUFA10 expression, one of the subunits of Complex I. To find the target of DLA, the binding affinity of Sirtuin 1 (SIRT1) to DLA and DLA derivatives with replaced two phenolic hydroxyls was detected using surface plasmon resonance and bilayer interferometry. The results showed that DLA could activate SIRT1 after I/R probably by binding to this protein, depending on phenolic hydroxyl. Moreover, the importance of SIRT1 to DLA effectiveness was confirmed through siRNA transfection in vitro. These results demonstrated that DLA was able to prevent I/R induced decrease in NDUFA10 expression, improve Complex I activity and mitochondrial function, eventually attenuate cardiac structure and function injury after I/R, which was possibly related to its ability of binding to and activating SIRT1.

Yang X.-Y.,Peking University | Zhao N.,Peking University | Liu Y.-Y.,Peking University | Hu B.-H.,Peking University | And 7 more authors.
Evidence-based Complementary and Alternative Medicine | Year: 2013

Cardiotonic pill (CP) is a compound Chinese medicine currently used in China for treatment of ischemic angina pectoris. Our previous results indicated that a single dosing of CP pretreatment at 0.8 g/kg attenuates ischemia/reperfusion- (I/R-) induced myocardial injury and cardiac microcirculatory disturbance. The present study aimed to investigate the effect of CP at low dosage in a multiple dosing manner and to uncover the mechanism of antioxidative activity of CP. Male Sprague-Dawley rats were subjected to left anterior descending artery occlusion for 30 min followed by 60 min reperfusion. CP was administrated daily by gavage for six days at 0.1, 0.4, and 0.8 g/kg/day before I/R. Results showed that multiple dosing of CP at three doses significantly reduced I/R-induced myocardial injury, microcirculatory disturbance, and oxidative stress. CP dramatically inhibited I/R-induced nicotinamide adenosine dinucleotide phosphate (NADPH) oxidase subunit gp91phox expression and p67phox and p47phox translocation from cytosol to cell membrane. Translocation of cytosolic subunits to membrane is required for the activation of NADPH oxidase. These data suggested that multiple dosing of CP at doses ranging from 0.1 to 0.8 g/kg/day reduced I/R-induced rat myocardial injury and microcirculatory disturbance, which was mediated by inhibition of NADPH oxidase activation. © 2013 Xiao-Yuan Yang et al.

Tang H.,Harbin Medical University | Pan C.-S.,Peking University | Pan C.-S.,Key Laboratory of Microcirculation | Pan C.-S.,Key Laboratory of Stasis and Phlegm | And 17 more authors.
Microcirculation | Year: 2014

Objective: TSI is a new drug derived from Chinese medicine for treatment of ischemic stroke in China. The aim of this study was to verify the therapeutic effect of TSI in a rat model of MCAO, and further explore the mechanism for its effect. Methods: Male Sprague-Dawley rats were subjected to right MCAO for 60 minutes followed by reperfusion. TSI (1.67 mg/kg) was administrated before reperfusion via femoral vein injection. Twenty-four hours after reperfusion, the fluorescence intensity of DHR 123 in, leukocyte adhesion to and albumin leakage from the cerebral venules were observed. Neurological scores, TTC staining, brain water content, Nissl staining, TUNEL staining, and MDA content were assessed. Bcl-2/Bax, cleaved caspase-3, NADPH oxidase subunits p47phox/p67phox/gp91phox, and AMPK/Akt/PKC were analyzed by Western blot. Results: TSI attenuated I/R-induced microcirculatory disturbance and neuron damage, activated AMPK, inhibited NADPH oxidase subunits membrane translocation, suppressed Akt phosphorylation, and PKC translocation. Conclusions: TSI attenuates I/R-induced brain injury in rats, supporting its clinic use for treatment of acute ischemic stroke. The role of TSI may benefit from its antioxidant activity, which is most likely implemented via inactivation of NADPH oxidase through a signaling pathway implicating AMPK/Akt/PKC. © 2014 John Wiley & Sons Ltd.

Deng J.-N.,Peking University | Deng J.-N.,Key Laboratory of Microcirculation | Deng J.-N.,Key Laboratory of Stasis and Phlegm | Li J.,Peking Union Medical College | And 19 more authors.
Evidence-based Complementary and Alternative Medicine | Year: 2015

This study was to explore the protective effects of Deepure tea against insulin resistance and hepatic steatosis and elucidate the potential underlying molecular mechanisms. C57BL/6 mice were fed with a high fat diet (HFD) for 8 weeks to induce the metabolic syndrome. In the Deepure tea group, HFD mice were administrated with Deepure tea at 160 mg/kg/day by gavage for 14 days. The mice in HFD group received water in the same way over the same period. The age-matched C57BL/6 mice fed with standard chow were used as normal control. Compared to the mice in HFD group, mice that received Deepure tea showed significantly reduced plasma insulin and improved insulin sensitivity. Deepure tea increased the expression of insulin receptor substrate 2 (IRS-2), which plays an important role in hepatic insulin signaling pathway. Deepure tea also led to a decrease in hepatic fatty acid synthesis and lipid accumulation, which were mediated by the downregulation of sterol regulatory element binding protein 1c (SREBP-1c), fatty acid synthesis (FAS), and acetyl-CoA carboxylase (ACC) proteins that are involved in liver lipogenesis. These results suggest that Deepure tea may be effective for protecting against insulin resistance and hepatic steatosis via modulating IRS-2 and downstream signaling SREBP-1c, FAS, and ACC. © 2015 Jing-Na Deng et al.

Tu L.,Peking University | Pan C.-S.,Peking University | Pan C.-S.,Key Laboratory of Microcirculation | Pan C.-S.,Key Laboratory of Stasis and Phlegm | And 26 more authors.
Microcirculation | Year: 2013

Objective: This study was designed to investigate the protective potential of AS-IV against ischemia and I/R-induced myocardial damage, with focusing on possible involvement of energy metabolism modulation in its action and the time phase in which it takes effect. Methods: SD rats were subjected to 30 minutes LADCA occlusion, followed by reperfusion. MBF, myocardial infarct size, and cardiac function were evaluated. Myocardial structure and myocardial apoptosis were assessed by double immunofluorescence staining of F-actin and TUNEL. Content of ATP, ADP, and AMP in myocardium, cTnI level, expression of ATP5D, P-MLC2, and apoptosis-related molecules were determined. Results: Pretreatment with AS-IV suppressed MBF decrease, myocardial cell apoptosis, and myocardial infarction induced by I/R. Moreover, ischemia and I/R both caused cardiac malfunction, decrease in the ratio of ATP/ADP and ATP/AMP, accompanying with reduction of ATP 5D protein and mRNA, and increase in P-MLC2 and serum cTnI, all of which were significantly alleviated by pretreatment with AS-IV, even early in ischemia phase for the insults that were implicated in energy metabolism. Conclusions: AS-IV prevents I/R-induced cardiac malfunction, maintains the integrity of myocardial structure through regulating energy metabolism. The beneficial effect of AS-IV on energy metabolism initiates during the phase of ischemia. © 2013 John Wiley & Sons Ltd.

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