RESUMO
Objective:To investigate the mechanism of resolvin D1 (RvD1) in alleviating brain injury after cardiopulmonary resuscitation (CPR) through regulating autophagy pathway in pigs.Methods:Nineteen male domestic pigs, weighing 30-41 kg, were divided into 3 groups using a random number table method: sham group (S group, n=5), CPR group ( n=7), and RvD1 group ( n=7). In the S group, the animals only experienced general preparation. In the CPR and RvD1 groups, the pig CPR model was established by 8 min of cardiac arrest caused by electrically induced ventricular fibrillation, and followed by 5 min of CPR. At 5 min after resuscitation, a dose of 0.6 μg/kg of resolvin D1 was injected via femoral vein in the RvD1 group, and the same amount of vehicle was similarly administered in the other two groups. At 1, 3, 6, and 24 h after resuscitation, blood samples were collected from the femoral vein to measure serum concentrations of neuron specific enolase (NSE) and S100β protein by ELISA. At 24 h after resuscitation, neurological function was evaluated by neurological deficit score (NDS), and then the animals were euthanized to obtain cerebral cortex for measuring the expressions of phosphorylated AMP-activated protein kinase (p-AMPK), phosphorylated mammalian target of rapamycin (p-mTOR), microtubule-associated protein light chain 3 (LC3 II) and p62 by Western blot. The variables were compared with One-way analysis of variance and then the Bonferroni test among the three groups. Results:During 24 h after resuscitation, the NDS was significantly increased accompanied with significantly greater concentrations of NSE and S100β in serum in the CPR and RvD1 groups compared to the S group (all P<0.05). However, the NDS was significantly decreased at 24 h after resuscitation [(182±34) vs.(124±18), P<0.05], and serum NSE and S100β were significantly reduced starting 3 h after resuscitation in the RvD1 group compared to the CPR group [NSE (ng/mL): (23.1±3.8) vs. (18.0±2.2) at 3 h, (27.3±2.9) vs. (19.8±1.4) at 6 h, and (28.1±1.3) vs. (15.1±2.1) at 24 h; S100B (pg/mL): (1 611±208) vs. (1 322±100) at 3 h, (1 825±197) vs. (1 410±102) at 6 h, and (1 613±138) vs. (1 183±139) at 24 h, all P<0.05]. The expression levels of p-AMPK and LC3 II were significantly increased while the expression levels of p-mTOR and p62 were significantly decreased at 24 h after resuscitation in the CPR and RvD1 groups compared to the S group (all P<0.05). However, the expression levels of p-AMPK and LC3 II were significantly lower and the expression levels of p-mTOR and p62 were significantly higher at 24 h after resuscitation in the RvD1 group compared to the CPR group [p-AMPK: (0.28±0.08) vs. (0.17±0.03); LC3 II: (0.33±0.09) vs. (0.21±0.04); p-mTOR: (0.13±0.02) vs. (0.16±0.02); p62: (0.16±0.05) vs. (0.22±0.02), all P<0.05]. Conclusions:The protective mechanism by which RvD1 alleviates brain injury after CPR in pigs might be related to the inhibition of neuronal autophagy mediated by AMPK/mTOR pathway.
RESUMO
Objective:To investigate the role of LncRNA-TUG1 in the injury of intestinal epithelial cells induced by lipopolysaccharide (LPS).Methods:LPS was used to treat HIEC-6 human intestinal epithelial cells for 24 h to construct a sepsis injury model. Whole transcriptome RNA sequencing was used to analyze the expression changes of mRNA, microRNA and lncRNA in HIEC-6 cells after LPS treatment. Real-time fluorescence quantitative (qRT-PCR) and Western blot was performed to detect the expression changes of lncRNA-TUG1, microRNA-132-3p (miR-132-3p), SIRT1 mRNA and SIRT1 protein in HIEC-6 cells after LPS treatment. The expression levels of LncRNA-TUG1, miR-132-3p and SIRT1 were artificially changed by in vitro transfection. qRT-PCR and Western blot were used to confirm the regulatory effect of lncRNA-TUG1 on microRNA-132-3p and SIRT1. CCK-8 and flow cytometry were used to analyze the effects of LncRNA-TUG1, miR-132-3p and SIRT1 on the proliferation and apoptosis of HIEC-6 cells. The dual luciferase report analysis was used to verify the targeting relationship between LncRNA-TUG1, miR-132-3p and SIRT1. Statistical analysis was performed using SPSS 17.0, and differences between the two groups were compared using independent sample t test. Results:RNA sequencing results showed that the expressions of lncRNA-TUG1 and SIRT1 were decreased in HIEC-6 cells after LPS treatment ( t=3.26, P<0.05 and t=2.55, P<0.05), but the expression of miR-132-3p was increased ( t=4.12, P<0.05). In vitro cell experiments, the expression of lncRNA-TUG1 and SIRT1 were decreased in HIEC-6 cells treated with LPS ( t=5.69, P<0.05 and t=5.712, P<0.05), while the expression of miR-132-3p was increased ( t=3.88, P<0.05). Overexpression of lncRNA-TUG1 increased the proliferation rate ( t=6.55, P<0.05) and decreased the apoptosis rate ( t=3.94, P<0.05) of LPS-treated cells. Upregulation of lncRNA-TUG1 decreased the expression of miR-132-3p ( t=4.66, P<0.05), and increased the mRNA and protein levels of SIRT1 ( t=3.91, P<0.05). Transfection of miR-132-3P mimic could inhibit the mRNA ( t=4.08, P<0.05) and protein levels of SIRT1. In LPS-treated cells, the cells co-transfected with miR-132-3pmimic and siRNA-SIRT1 had a lower proliferation rate ( t=4.55, P<0.05 and t=5.67, P<0.05) and a higher apoptosis rate ( t=3.90, P<0.05 and t=4.22, P<0.05) than those transfected with only pcDNA3.1-lncRNA-TUG. Conclusions:lncRNA-TUG1 may act as a ceRNA to regulate miR-132-3p/SIRT1, therefore alleviating HIEC-6 cell injury caused by LPS. Intervention of lncRNA-TUG1/miR-132-3p/SIRT1 regulatory pathway may become a potential strategy to prevent sepsis-induced intestinal mucosal damage.