ABSTRACT
Objective:To explore the relationship between low serum albumin levels and its duration on first episode of peritonitis in peritoneal dialysis (PD) patients.Methods:PD patients who were regularly followed up in the Pearl River Delta region from September 1, 2000 to July 6, 2021 in Shunde Hospital of Southern Medical University, Nanfang Hospital of Southern Medical University, and Foshan First People′s Hospital were retrospectively selected. The patients were divided into low serum albumin group (LSA group, mean albumin<35 g/L), moderate serum albumin group (MSA group, 35 g/L≤mean albumin<40 g/L) and high serum albumin group (HSA group, mean albumin≥40 g/L) according to the mean albumin of the patients, and the differences among the three groups were compared. The Kaplan-Meier survival analysis method was used to compare the risk of peritonitis events in different mean albumin groups and different durations of hypoalbuminemia. The multivariate Cox regression model was used to analyze the relationship between serum albumin levels and duration of hypoalbuminemia and new-onset peritonitis.Results:A total of 1 853 PD patients were included in this study, aged (49.72±15.34) years, and 1 036(55.9%) males. There were 551 patients (29.7%) in the LSA group, 920 patients (49.7%) in the MSA group, and 382 patients (20.6%) in the HSA group. The median follow-up was 37 (15, 66) months and there were 508 patients (27.4%) with new-onset peritonitis during the follow-up. Compared with the LSA group, the incidence of new peritonitis in the MSA group and HSA group was lower ( χ2=14.053, P<0.001; χ2=21.857, P<0.001), but there was no significant difference in the incidence of new peritonitis between the HSA group and MSA group. The Kaplan-Meier survival analysis showed that the cumulative incidence of peritonitis in the LSA group was significantly higher than that in the MSA group and HSA group (Log-rank χ2=22.128, P<0.001). Compared with PD patients with normal serum albumin, the patients with longer duration of hypoalbuminemia tended to have a higher incidence of new peritonitis. Multivariate Cox regression analysis showed that the mean albumin<35 g/L (LSA group/MSA group, HR=1.495, 95% CI 1.198-1.866, P<0.001; LSA group/HSA group, HR=1.459, 95% CI 1.104-1.928, P=0.008) was an independent risk factor of new-onset peritonitis in PD patients and the prolongation of duration of hypoalbuminemia had a significantly higher risk of new-onset peritonitis ( HR=1.013, 95% CI 1.003-1.024, P=0.014). Conclusion:The mean albumin<35 g/L and prolong duration of hypoalbuminemia are independent risk factors of PD-related peritonitis in PD patients.
ABSTRACT
Objective To explore the role and mechanism of microRNA-15b in the regulation of epithelial-mesenchymal transition (EMT) of human peritoneal mesothelial cells (HPMCs).Methods PCR assay was used to determine the expression of microRNA-15b in the HMrSV5 induced by 138mmol/L high glucose for 24 h.MicmRNA-15b mimic or inhibitor was transfected into human peritoneal mesothelial cells (HMrSV5) to over-express or down-regulate microRNA-15b.The cells were then incubated with 138 mmol/L high glucose for 24 h,and the expressions of E-cadherin(E-Cad),Vimentin (VIM),Fibronectin(FN) and Smad7 were detected by real-time PCR and Western blotting respectively.Results microRNA-15b in the HMrSV5 ceils was over-expressed and down-regulated.Increased level of microRNA-15b was obtained in HMrSV5 cells treated with high glucose.In vitro,high glucose led to the up-regulation of vimentin as well as fibronectin and the down-regulation of E-cadherin in HMrSV5 cells (all P ＜ 0.05),which indicated EMT and fibrosis.Suppression of microRNA-15b by transfection with microRNA-15b inhibitor partially reversed the EMT and fibrosis changes (P ＜ 0.05),while over-expression of microRNA-15b by transfection with microRNA-15b mimic obviously enhanced the EMT and fibrosis changes (P ＜ 0.05).Conclusions MicroRNA-15b mediates high glucose induced EMT in human peritoneal mesothelial cells by the inhibition of Smad7 possibly.MicroRNA-15b maybe a new target for the prevention and treatment of peritoneal fibrosis during peritoneal dialysis (PD).