To investigate whether the expression of exogenous heme oxygenase-1 (HO-1) gene within vascular smooth muscle cells (VSMC) could protect the cells from free radical attack and inhibit cell proliferation, we establishe...To investigate whether the expression of exogenous heme oxygenase-1 (HO-1) gene within vascular smooth muscle cells (VSMC) could protect the cells from free radical attack and inhibit cell proliferation, we established an in vitro transfection of human HO-1 gene into rat VSMC mediated by a retroviral vector. The results showed that the profound expression of HO-1 protein as well as HO activity was 1.8- and 2.0-fold increased respectively in the transfected cells compared to the non-transfected ones. The treatment of VSMC with different concentrations of H2O2 led to the remarkable cell damage as indicated by survival rate and LDH leakage. However, the resistance of the HO-1 transfected VSMC against H2O2 was significantly raised. This protective effect was dramatically diminished when the transfected VSMC were pretreated with ZnPP-IX, a specific inhibitor of HO, for 24 h. In addition, we found that the growth potential of the transfected cells was significantly inhibited directly by increased activity of HO-1, and this effect might be related to decreased phosphorylation of MAPK. These results suggest that the overexpression of introduced hHO-1 is potentially able to reduce the risk factors of atherosclerosis, partially due to its cellular protection against oxidative injury and to its inhibitory effect on cellular proliferation.展开更多
Background Skeletal muscle has recently been recognized as an endocrine organ that can express, synthesize and secrete a variety of bioactive molecules which exert significant regulatory effects. Hydrogen sulfide （H2...Background Skeletal muscle has recently been recognized as an endocrine organ that can express, synthesize and secrete a variety of bioactive molecules which exert significant regulatory effects. Hydrogen sulfide （H2S） iS endogenously produced in mammalian tissues and participates in a number of physiological and pathophysiological processes. We aimed to verify whether H2S could be endogenously generated and released by rat skeletal muscle, and determine the biological effects of H2S in rat skeletal muscle. Methods The study was divided into two parts： detection of endogenous H2S generation and release in rat skeletal muscle and determination of antioxidative activity of skeletal muscle-derived H2S. H2S content and production in tissues were ,detected by sensitive sulfur electrode method. The expressions of H2S producing enzymes cystathionine i^-synthase, cystathionine y-lyase and mercaptopyruvate sulfurtransferase were detected by real-time PCR and western blotting and their tissue distributions were observed by immunohistochemical and immunofluorescent analysis. Rat skeletal muscular ischemia-reperfusion （I-R） injury model was created and evaluated by histological analysis under microscope. The malondialdehyde （MDA） contents, hydrogen peroxide levels, superoxide anion and superoxide dismutase （SOD） activities were detected using spectrophotometer. Results H2S could be endogenously generated and released by skeletal muscle of Sprague-Dawley rats （H2S content： （2.06＋0.43） nmol/mg; H2S production： （0.17＋0.06） nmol.minl.mgl）. Gene and protein expressions of the three H2S producing enzymes ~vere detected in skeletal muscle, as well as the liver and kidney. Endogenous H2S content and production were decreased in skeletal muscles of rats with I-R skeletal muscle injury （P 〈0.05）. Furthermore, H2S significantly protected rat skeletal muscle against I-R injury and resulted in decreased MDA content, reduced hydrogen peroxide and superoxide anion levels, but increased SOD activi展开更多
Cardiovascular diseases （CVDs） are major causes of death worldwide. Identification of promising targets for prevention and treatment of CVDs is paramount in the cardiovascular field. Numerous transcription factors r...Cardiovascular diseases （CVDs） are major causes of death worldwide. Identification of promising targets for prevention and treatment of CVDs is paramount in the cardiovascular field. Numerous transcription factors regulate cellular function through modulation of spe- cific genes and thereby are involved in the physiological and pathophysiologicai processes of CVDs. Although Kriippel-like factors （KLFs） have a similar protein structure with a conserved zinc finger domain, they possess distinct tissue and cell distribution patterns as well as biological functions. In the vascular system, KLF activities are regulated at both transcriptional and posttranscriptional levels. Growing in vitro, in vivo, and genetic epidemiology studies suggest that specific KLFs play important roles in vascular walt biology, which further affect vascular diseases. KLFs regulate various functional aspects such as cell growth, differentiation, activa- tion, and development through controlling a whole cluster of functionally related genes and modulating various signaling pathways in response to pathological conditions. Therapeutic targeting of selective KLF family members may be desirable to achieve distinct treatment effects in the context of various vascular diseases. Further elucidation of the association of KLFs with human CVDs, their underlying molecular mechanisms, and precise protein structure studies will be essential to define KLFs as promising targets for therapeutic interventions in CVDs.展开更多
Metabolic stress is a physiological process that occurs during exercise in response to low energy that leads to metabolite accumulation [lactate, phosphate inorganic(Pi) and ions of hydrogen(H^+)] in muscle cells.Trad...Metabolic stress is a physiological process that occurs during exercise in response to low energy that leads to metabolite accumulation [lactate, phosphate inorganic(Pi) and ions of hydrogen(H^+)] in muscle cells.Traditional exercise protocol(i.e., Resistance training) has an important impact on the increase of metabolite accumulation, which influences hormonal release, hypoxia, reactive oxygen species(ROS) production and cell swelling.Changes in acute exercise routines, such as intensity, volume and rest between sets, are determinants for the magnitude of metabolic stress, furthermore, different types of training, such as lowintensity resistance training plus blood flow restriction and high intensity interval training, could be used to maximize metabolic stress during exercise.Thus, the objective of this review is to describe practical applications that induce metabolic stress and the potential effects of metabolic stress to increase systemic hormonal release, hypoxia, ROS production, cell swelling and muscle adaptations.展开更多
基金This work was kindly supported by Na-tional Natural Science Foundation of China(No.39670308)
文摘To investigate whether the expression of exogenous heme oxygenase-1 (HO-1) gene within vascular smooth muscle cells (VSMC) could protect the cells from free radical attack and inhibit cell proliferation, we established an in vitro transfection of human HO-1 gene into rat VSMC mediated by a retroviral vector. The results showed that the profound expression of HO-1 protein as well as HO activity was 1.8- and 2.0-fold increased respectively in the transfected cells compared to the non-transfected ones. The treatment of VSMC with different concentrations of H2O2 led to the remarkable cell damage as indicated by survival rate and LDH leakage. However, the resistance of the HO-1 transfected VSMC against H2O2 was significantly raised. This protective effect was dramatically diminished when the transfected VSMC were pretreated with ZnPP-IX, a specific inhibitor of HO, for 24 h. In addition, we found that the growth potential of the transfected cells was significantly inhibited directly by increased activity of HO-1, and this effect might be related to decreased phosphorylation of MAPK. These results suggest that the overexpression of introduced hHO-1 is potentially able to reduce the risk factors of atherosclerosis, partially due to its cellular protection against oxidative injury and to its inhibitory effect on cellular proliferation.
基金The study was supported by the grants from Major Basic Research Development Program of People＇s Republic of China （No. 2011CB503904 and No. 2013CB933801） and National Natural Science Foundation of China （No. 81070212）.
文摘Background Skeletal muscle has recently been recognized as an endocrine organ that can express, synthesize and secrete a variety of bioactive molecules which exert significant regulatory effects. Hydrogen sulfide （H2S） iS endogenously produced in mammalian tissues and participates in a number of physiological and pathophysiological processes. We aimed to verify whether H2S could be endogenously generated and released by rat skeletal muscle, and determine the biological effects of H2S in rat skeletal muscle. Methods The study was divided into two parts： detection of endogenous H2S generation and release in rat skeletal muscle and determination of antioxidative activity of skeletal muscle-derived H2S. H2S content and production in tissues were ,detected by sensitive sulfur electrode method. The expressions of H2S producing enzymes cystathionine i^-synthase, cystathionine y-lyase and mercaptopyruvate sulfurtransferase were detected by real-time PCR and western blotting and their tissue distributions were observed by immunohistochemical and immunofluorescent analysis. Rat skeletal muscular ischemia-reperfusion （I-R） injury model was created and evaluated by histological analysis under microscope. The malondialdehyde （MDA） contents, hydrogen peroxide levels, superoxide anion and superoxide dismutase （SOD） activities were detected using spectrophotometer. Results H2S could be endogenously generated and released by skeletal muscle of Sprague-Dawley rats （H2S content： （2.06＋0.43） nmol/mg; H2S production： （0.17＋0.06） nmol.minl.mgl）. Gene and protein expressions of the three H2S producing enzymes ~vere detected in skeletal muscle, as well as the liver and kidney. Endogenous H2S content and production were decreased in skeletal muscles of rats with I-R skeletal muscle injury （P 〈0.05）. Furthermore, H2S significantly protected rat skeletal muscle against I-R injury and resulted in decreased MDA content, reduced hydrogen peroxide and superoxide anion levels, but increased SOD activi
文摘Cardiovascular diseases （CVDs） are major causes of death worldwide. Identification of promising targets for prevention and treatment of CVDs is paramount in the cardiovascular field. Numerous transcription factors regulate cellular function through modulation of spe- cific genes and thereby are involved in the physiological and pathophysiologicai processes of CVDs. Although Kriippel-like factors （KLFs） have a similar protein structure with a conserved zinc finger domain, they possess distinct tissue and cell distribution patterns as well as biological functions. In the vascular system, KLF activities are regulated at both transcriptional and posttranscriptional levels. Growing in vitro, in vivo, and genetic epidemiology studies suggest that specific KLFs play important roles in vascular walt biology, which further affect vascular diseases. KLFs regulate various functional aspects such as cell growth, differentiation, activa- tion, and development through controlling a whole cluster of functionally related genes and modulating various signaling pathways in response to pathological conditions. Therapeutic targeting of selective KLF family members may be desirable to achieve distinct treatment effects in the context of various vascular diseases. Further elucidation of the association of KLFs with human CVDs, their underlying molecular mechanisms, and precise protein structure studies will be essential to define KLFs as promising targets for therapeutic interventions in CVDs.
文摘Metabolic stress is a physiological process that occurs during exercise in response to low energy that leads to metabolite accumulation [lactate, phosphate inorganic(Pi) and ions of hydrogen(H^+)] in muscle cells.Traditional exercise protocol(i.e., Resistance training) has an important impact on the increase of metabolite accumulation, which influences hormonal release, hypoxia, reactive oxygen species(ROS) production and cell swelling.Changes in acute exercise routines, such as intensity, volume and rest between sets, are determinants for the magnitude of metabolic stress, furthermore, different types of training, such as lowintensity resistance training plus blood flow restriction and high intensity interval training, could be used to maximize metabolic stress during exercise.Thus, the objective of this review is to describe practical applications that induce metabolic stress and the potential effects of metabolic stress to increase systemic hormonal release, hypoxia, ROS production, cell swelling and muscle adaptations.
