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Maintaining the health of the endothelium is of critical importance to prevention against cell aging. The current study was performed to clarify the role of sirtuin1 (SIRT1) in platelet phagocytosis in cell aging and identified its downstream molecular mechanism. Platelet phagocytosis by human endometrial microvascular endothelial cells (HEMECs) was characterized by transmission electron and fluorescence microscopy. Functional experiments were conducted to examine platelet phagocytosis and cell aging using the overexpression or knockdown plasmids of SIRT1 and G alpha-interacting, vesicle-associated protein (GIRDIN) as well as Akt inhibitor and activator. It was found that SIRT1 facilitated platelet phagocytosis by HEMECs, contributing to inhibition of cell aging. Akt activation facilitated platelet phagocytosis and repressed cell aging. GIRDIN overexpression accelerated platelet phagocytosis by HEMECs, leading to a delay in cell aging. GIRDIN phosphorylation at Ser1417 was induced by Akt activation, while activation of Akt was induced by SIRT1-mediated deacetylation, consequently augmenting platelet phagocytosis and delaying cell aging. Taken together, SIRT1 delayed aging of HEMECs by deacetylating Akt, phosphorylating GIRDIN, and inducing platelet phagocytosis. The study highlights a possible target for the prevention of HEMEC aging.

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Mono (2-ethylhexyl) phthalate (MEHP) is a major metabolite of di (2-ethylhexyl) phthalate (DEHP). This study aimed to observe the toxic effect of MEHP on human endometrial microvascular endothelial cells (HEMECs) and its potential molecular mechanism. HEMECs were exposed to different concentrations of MEHP (0, 50, 100, and 200 nM). Cell viability and apoptosis were assessed by cell counting kit-8 (CCK-8) and flow cytometry assays. Western blot was performed to examine the expression of apoptosis-related proteins (Bcl-2, Bax, and Caspase-3). Moreover, the expression of pyroptosis-related Caspase-1 was detected by western blot and immunofluorescence assays. Lactate dehydrogenase (LDH) release levels were evaluated in HEMECs treated with MEHP and/or Caspase-1 inhibitor Ac-YVAD-CHO. After exposure to MEHP, NLRP3 expression was examined by reverse transcription quantitative polymerase chain reaction (RT-qPCR) and western blot. LDH release and apoptosis levels were tested in HEMECs induced by MEHP and/or siNLRP3. MEHP significantly induced cell viability and inhibited apoptosis for HEMECs, with a concentration-dependent manner. Furthermore, Bcl-2/Bax ratio was distinctly reduced and Caspase-3 expression was increased in HEMECs after exposure to MEHP. Western blot and immunofluorescence results confirmed that MEHP markedly augmented Caspase-1 expression in HEMECs. Furthermore, LDH release levels were fortified in HEMECs treated with MEHP, which were improved following cotreatment with Ac-YVAD-CHO. At the mRNA and protein levels, NLRP3 expression was prominently increased in HEMECs exposed to MEHP. NLRP3 knockdown markedly ameliorated the increase in LDH release and apoptosis induced by MEHP exposure in HEMECs. Our findings suggested that exposure to MEHP facilitates apoptosis and pyroptosis of HEMECs through NLRP3 inflammasome.

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This study aimed to observe the effects of Selenium (Se) on aflatoxin B1 (AFB1)-induced uterine injury in female mice and necrosis of human endometrial microvascular endothelial cells (HEMECs). Fifty female mice were randomly divided into control group; AFB1 group; Se group (0.2 mg/kg each day); AFB1 + Se group; and positive control group. After continuous treatment for 30 days, uterine tissues were harvested, which were used for hematoxylin and eosin (H&E) staining. Necrosis-related proteins including RIPK1, RIPK3, and MLKL were examined in uterine tissues using western blot and immunohistochemistry. HEMECs were treated with different concentrations of AFB1 or Se, which were used for selecting the optimal concentrations. RIPK1, RIPK3 and MLKL expression was detected in HEMECs exposed to AFB1 and/or Se via western blot and immunofluorescence. H&E staining results showed that AFB1 induced uterine injury of female male, which was ameliorated by Se treatment. According to western blot and immunohistochemistry, RIPK1, RIPK3, and MLKL expression was distinctly increased in uterine tissues of AFB1-treated mice, which was decreased by Se treatment. Cell viability of HEMECs was gradually lowered as the concentrations of AFB1and Se increased. A 10-µM AFB1 exposure significantly increased RIPK1, RIPK3, and MLKL expression in HEMECs, which was improved following co-treatment with 5-µM Se. Thus, our findings revealed that Se may ameliorate AFB1-induced uterine injury in female mice and necrosis of HEMECs.

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