Yuezhu Zhang,Shuyue Wang,Tianyang Zhao,Liwei Yang,Shuangyu Guo,Yanbin Shi,Xueting Zhang,Liting Zhou,Lin Ye
Mono-2-ethylhexyl phthalate (MEHP), as the major metabolite of Di-(2-ethylhexyl) phthalate (DEHP), can induce lipid accumulation in hepatocytes and further leads to non-alcoholic fatty liver disease (NAFLD), while the underlying mechanism is unclear. We aim to clarify the effects of JAK2/STAT5 pathway on lipid accumulation induced by MEHP and the role of oxidation stress in NAFLD. BRL-3A hepatocytes were exposed to MEHP (0, 10, 50, 100 and 200 μM) for 24 h and 48 h. Then the lipid droplets in cells were observed by Oil-Red-O staining and quantified by isopropyl alcohol . The levels of TG, SOD, TBARS, AST and ALT were all detected by commercial kits. RT-PCR was used to detect mRNA expression, and western blotting was used to detect the expression of proteins encoded by JAK2/STAT5 pathway genes and lipid metabolism-related genes. As a result, MEHP promoted the lipid synthesis and accumulation in BRL-3A cells. MEHP down-regulated the expression and inhibited the activation of JAK2/STAT5. Moreover, the lipid metabolism-related kinases levels were elevated after MEHP exposure. In addition, the SOD levels were gradually decreased and the TBARS levels were increased in MEHP-treated groups. The lipid metabolism-related proteins levels were correlated with the oxidation stress levels. Furthermore, the ALT and AST levels were elevated after MEHP exposure. Therefore, we concluded that MEHP led to lipid accumulation through inhibiting JAK2/STAT5 pathway, resulted in damaging liver parenchyma and NAFLD by aggravating oxidation stress.
Lin Yifeng,Dong Shunni,Ye Xiaohang,Liu Juan,Li Jiaqun,Zhang Yanye,Tu Mixue,Wang Siwen,Ying Yanyun,Chen Ruixue,Wang Feixia,Ni Feida,Chen Jianpeng,Du Binyang,Zhang Dan
Background Thin endometrium is a primary cause of defective endometrial receptivity, resulting in infertility or recurrent miscarriage. Much effort has been devoted toward regenerating thin endometrium by stem cell-based therapies. The human placenta-derived mesenchymal stem cells (HP-MSCs) are emerging alternative sources of MSCs with various advantages. To maximize their retention inside the uterus, we loaded HP-MSCs with cross-linked hyaluronic acid hydrogel (HA hydrogel) to investigate their therapeutic efficacy and possible underlying mechanisms.
Methods Ethanol was injected into the mice uterus to establish the endometrium-injured model. The retention time of HP-MSCs and HA hydrogel was detected by in vivo imaging, while the distribution of HP-MSCs was detected by immunofluorescence staining. Functional restoration of the uterus was assessed by testing embryo implantation rates. The endometrial morphological alteration was observed by H&E staining, Masson staining, and immunohistochemistry. In vitro studies were further conducted using EdU, transwell, tube formation, and western blot assays. Results Instilled HP-MSCs with HA hydrogel (HP-MSCs-HA) exhibited a prolonged retention time in mouse uteri than normal HP-MSCs. In vivo studies showed that the HP-MSCs-HA could significantly increase the gland number and endometrial thickness ( P < 0.001, P < 0.05), decrease fibrous area ( P < 0.0001), and promote the proliferation and angiogenesis of endometrial cells (as indicated by Ki67 and VEGF, P < 0.05, P < 0.05, respectively) in mice injured endometrium. HP-MSCs-HA could also significantly improve the embryo implantation rate ( P < 0.01) compared with the ethanol group. Further mechanistic study showed the paracrine effects of HP-MSCs. They could not only promote the proliferation and migration of human endometrial stromal cells via the JNK/Erk1/2-Stat3-VEGF pathway but also facilitate the proliferation of glandular cells via Jak2-Stat5 and c-Fos-VEGF pathway. In turn, the increased VEGF in the endometrium promoted the angiogenesis of endothelial cells. Conclusion Our study suggested the potential therapeutic effects and the underlying mechanisms of HP-MSCs-HA on treating thin endometrium. HA hydrogel could be a preferable delivery method for HP-MSCs, and the strategy represents a promising therapeutic approach against endometrial injury in clinical settings. Graphical abstract