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Pathogenesis and treatment for diabetic neuropathy are still complex. A deficit of neurotrophic factors affecting Schwann cells is a very important cause of diabetic neuropathy. Neuritin is a newly discovered potential neurotrophic factor. In this study, we explored the effect of exogenous neuritin on survivability and functions of diabetic Schwann cells of rats with experimental diabetic neuropathy. Diabetic neuropathy was induced in rats. 12‐week diabetic rats contrasted with non‐diabetic normal rats had decreased levels of serum neuritin and slowed nerve conduction velocities (NCVs). Schwann cells isolated from these diabetic rats and cultured in high glucose showed reduced cell neuritin mRNA and protein and supernatant neuritin protein, increased apoptosis rates, increased caspase‐3 activities and progressively reduced viability. In contrast, exogenous neuritin treatment reduced apoptosis and improved viability, with elevated Bcl‐2 levels (not Bax) and decreased caspase‐3 activities. Co‐cultured with diabetic Schwann cells pre‐treated with exogenous neuritin in high glucose media, and diabetic DRG neurons showed lessened decreased neurite outgrowth and supernatant NGF concentration occurring in co‐culture of diabetic cells. Exogenous neuritin treatment ameliorated survivability and functions of diabetic Schwann cells of rats with diabetic neuropathy. Our study may provide a new mechanism and potential treatment for diabetic neuropathy.  相似文献   
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In this study, total flavonoids and total triterpenoid acid were extracted with ethyl acetate from Hedyotis diffusa Willd, and hepatoprotective activities of them and five compounds from total flavonoids against H2O2 induced hepatocyte damage on HL‐02 cells were determined. In particular, amentoflavone and total flavonoids had influence on the leakage of ALT, AST, LDH, the activities of SOD and the content of MDA. They effectively reduced the loss of MMP, the release of Cyt C, and then inhibited activation of caspase‐3/caspase‐9 cascade in hepatotoxic cells. The contents of ROS were significantly reduced to inhibit p38 in amentoflavone and flavonoids groups which decreased ASK1 and p‐p38 levels through increasing thioredoxin Trx1 and reductase TrxR1. These results suggesting that the antioxidant protection of amentoflavone and flavonoids might be reducing ROS to inhibit the H2O2‐induced upstream of pathway via increasing levels of Trx1 and TrxR1, which were pivotal in blocking the down streaming effectors of ASK1/p38 MAPK pathway and alleviating hepatotoxicity.  相似文献   
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Shen  He  Wu  Shuyu  Chen  Xi  Xu  Bai  Ma  Dezun  Zhao  Yannan  Zhuang  Yan  Chen  Bing  Hou  Xianglin  Li  Jiayin  Cao  Yudong  Fu  Xianyong  Tan  Jun  Yin  Wen  Li  Juan  Meng  Li  Shi  Ya  Xiao  Zhifeng  Jiang  Xingjun  Dai  Jianwu 《中国科学:生命科学英文版》2020,63(12):1879-1886
Science China Life Sciences - Spinal cord injury (SCI), especially complete transected SCI, leads to loss of cells and extracellular matrix and functional impairments. In a previous study, we...  相似文献   
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Idiopathic pulmonary fibrosis (IPF) is a progressive disease characterized by excessive deposition of extracellular matrix (ECM) and chronic inflammation with limited therapeutic options. Psoralen, a major active component extracted from Psoralea corylifolia L. seed, has several biological effects. However, the role of psoralen in IPF is still unclear. Here, we hypothesized that psoralen played an essential role in IPF in the inhibition of fibroblast proliferation and inflammatory response. A murine model of IPF was established by injecting bleomycin (BLM) intratracheally, and psoralen was administered for 14 days from the 7th to 21st day after BLM injection. Our results demonstrated that psoralen treatment reduced body weight loss and improved the survival rate of mice with IPF. Histological and immunofluorescent examination showed that psoralen alleviated BLM‐induced lung parenchymal inflammatory and fibrotic alteration. Furthermore, psoralen inhibited proliferation and collagen synthesis of mouse fibroblasts and partially reversed BLM‐induced expression of α‐smooth muscle actin at both the tissue and cell level. Moreover, psoralen decreased the expression of transforming growth factor‐β1, interleukin‐1β, and tumor necrosis factor‐α in the lungs of BLM‐stimulated mice. Our results reveale for the first time that psoralen exerts therapeutic effects against IPF in a BLM‐induced murine model.  相似文献   
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Medical staff treating Coronavirus Disease 2019 (COVID-19) patients are at high risk for exposure to Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), and many have been infected, which may cause panic among medical workers, their relatives, health professionals, and government leaders. We report the epidemiologic and clinical characteristics of healthcare workers and that the majority of infected medical staff had milder symptoms/conditions with a better prognosis than admitted patients. Timely improvement to medical staff’s working conditions such as allowing adequate rest and providing sufficient medical protection is extremely important.  相似文献   
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