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• BMSC-Exos can protect neurons from excitotoxicity induced by glutamate. • The neuroprotective effect of BMSC-Exos is achieved by alleviating neuronal apoptosis. • BMSC-Exos alleviate neuronal apoptosis via PI3K/Akt/mTOR signaling. Many central nervous system diseases are closely related to nerve damage caused by dysregulation of the endogenous neurotransmitter glutamate. Exosomes derived from bone marrow mesenchymal stem cells (BMSC-Exos) play an important role in improving injury and regeneration functions. However, its mechanism remains unknown. Therefore, the aim of this study is to investigate whether and how BMSC-Exos improve neurotoxicity caused by glutamate and to fill the gap in the literature. In this study, glutamate-treated HT22 cells were first exposed to mouse-derived BMSC-Exos at different concentrations to observe their effects on HT22 apoptosis. Next, we treated glutamate-treated HT22 cells with mouse-derived BMSC-Exos. We then inhibited the PI3K/Akt/mTOR signaling pathways using the PI3K/Akt inhibitor and the mTOR inhibitor, respectively, and observed the protective effect of mouse-derived BMSC-Exos on HT22 cells treated with glutamate. Our results show that BMSC-Exos reduced apoptosis triggered by glutamate stimulation, increased cell vitality, and decreased the levels of proapoptotic proteins while increasing the levels of anti-apoptotic proteins. The protective effect of BMSC-Exos was weakened when PI3K/Akt inhibitor and mTOR inhibitor were added. To sum up, we draw the following conclusions: BMSC-Exos can reduce neuronal apoptosis and apoptosis-related protein expression after glutamate stimulation by regulating the PI3K/Akt/mTOR signaling pathway. [ABSTRACT FROM AUTHOR]

Abstract: Paeonol, a phenolic component from the root bark of Paeonia moutan, is traditionally used as a Chinese herbal medicine to activate the blood flow and remove blood stasis. Evidence shows that paeonol have anti-tumor, anti-inflammatory, and analgesic effects; however, the underlying mechanisms remain unknown. In this study, we investigated the molecular mechanisms by which paeonol exerts the anti-tumor effects by using a murine model of hepatoma established by in vivo injection of mouse HepA-hepatoma cells. Treatment of mice with 100, 200, or 400 mg/kg/day of paeonol significantly inhibited the growth of the HepA tumor in mice, induced HepA cell apoptosis as demonstrated by light microscopy and electron microscopy analyses, decreased the expression of Bcl-2 and increased the expression of Bax in HepA tumor tissues in a dose-related manner. Administration of paeonol in vivo also elevated serum levels of IL-2 and TNF-α in tumor-bearing mice. Moreover, splenocytes and macrophages isolated from paeonol-treated HepA tumor-bearing mice produced higher levels of IL-2 and TNF-α in response to concanavalin A and lipopolysaccharide stimulation, respectively, compared to these isolated from non-treated HepA tumor-bearing mice. In vitro treatment with paeonol was able to directly stimulate IL-2 and TNF-α production in splenocytes and macrophages from tumor-bearing mice, respectively. In conclusion, paeonol has the anti-tumor effect against hepatoma cells, which are likely mediated via induction of tumor cell apoptosis and stimulation of IL-2 and TNF-α production. Paeonol could be a promising drug to treat hepatocellular carcinoma. [Copyright &y& Elsevier]

Poria cocos polysaccharides (PCP) are abundant in Poria cocos (Schw.) Wolf (Poria). This is a common traditional Chinese medicine used to treat gastrointestinal and liver diseases. Poria cocos dispel dampness and enhance gastrointestinal functions, strongly affecting the treatment of non-alcoholic fatty liver disease. Still, the mechanism is not yet clear. The latest research found that protecting the integrity of the intestinal barrier can slow down the progression of non-alcoholic fatty liver disease (NAFLD). Hence, our research ought to explore the protective mechanism of PCP on the intestinal barrier under a high-fat diet and to clarify the relationship between intestinal barrier damage and steatohepatitis. H&E staining was done to evaluate pathological damage, whereas Nile red and oil red O staining was conducted to evaluate hepatic fat infiltration. Immunofluorescence staining and immunohistochemical staining were used to detect protein expression and locations. Bone marrow-derived macrophages were isolated for in vitro experiments. ONOO- and ROS fluorescent probes and MDA, SOD, and GSH kits assessed the levels of nitrogen and oxidative stress. LPS levels were detected with a Limulus Amebocyte Lysate assay. The Western blot analysis and reverse transcription-quantitative PCR detected the expression of related proteins and genes. The Elisa kit detected the level of the inflammatory factors in the cell supernatant. For the vivo NAFLD experiments, in briefly, mice were randomly chosen to receive either a High-fat diet or control diet for 12 weeks. Drug treatments started after 4 weeks of feeding. Zebrafish larvae were raised separately in fish water or 7 mM thioacetamide as the control or model group for approximately 72 h. In the therapy groups, different concentrations of PCP were added to the culture environment at the same time. In zebrafish, we determined the safe concentration of PCP and found that PCP could effectively reduce the pathological damage in the liver and intestines induced by the NAFLD model. In mice, PCP could slow down weight gain, hyperlipidemia, and liver steatosis caused by a high-fat diet. More importantly, PCP could reduce the destruction of the gut-vascular barrier and the translocation of endotoxins caused by a high-fat diet. Further, we found that PCP could inhibit intestinal pyroptosis by regulating PARP-1. Pyroptosis inhibitors, such as MCC950, could effectively protect the intestinal and liver damage induced by a high-fat diet. We also found that pyroptosis mainly occurred in intestinal macrophages. PCP could effectively improve the survival rate of bone marrow-derived macrophages in a high-fat environment and inhibit pyroptosis. These results indicated that PCP inhibited the pyroptosis of small intestinal macrophages to protect the intestinal barrier integrity under a high-fat diet. This resulted in decreased endotoxin translocation and progression of steatohepatitis. [Display omitted] • The therapeutic effect of Poria cocos polysaccharides on NAFLD was demonstrated from the gut-liver axis. • High-Fat Diet aggravates the gut vascular barrier disruption via macrophages-pyroptosis in NAFLD. • Poria cocos polysaccharides inhibited NLRP3-mediated pyroptosis to ameliorate small intestine barrier injury. [ABSTRACT FROM AUTHOR]

Methylglyoxal (MGO), a cytotoxic byproduct of glycolysis in biological systems, can induce endothelial cells dysfunction, implicated in diabetic vascular complications. Pterostilbene (PTS), a naturally occurring resveratrol derivative, is involved in various pharmacological activities. This study aimed to explore the effects of PTS on MGO induced cytotoxicity in human umbilical vein endothelial cells (HUVECs) and the underlying mechanisms for the first time. In the current study, it has been demonstrated that PTS could enhance the level of glyoxalase 1 (GLO-1) and elevate glutathione (GSH) content to active the glyoxalase system, resulting in elimination of the toxic MGO as well as advanced glycation end products (AGEs) in HUVECs. Meanwhile, PTS could also suppress oxidative stress and thus exert cytoprotective effects by elevating Nrf2 nuclear translocation and the corresponding down-stream antioxidant enzymes in MGO induced HUVECs. In addition, PTS could alleviate MGO induced apoptosis in HUVECs via inhibition of oxidative stress and associated downstream mitochondria-dependent signaling apoptotic cascades, as characterized by preventing caspases family activation. Taken together, these findings suggest that PTS could protect against MGO induced endothelial cell cytotoxicity by regulating glyoxalase, oxidative stress and apoptosis, suggesting that PTS could be beneficial in the treatment of diabetic vascular complications. [Display omitted] • MGO induced oxidative stress and apoptosis in endothelial cells. • Pterostilbene ameliorated MGO-induced cytotoxicity in HUVECs. • Pterostilbene relieved MGO-induced cytotoxicity by regulating glyoxalase, oxidative stress and apoptosis. [ABSTRACT FROM AUTHOR]