| Objective: Peritoneal dialysis,as one of the effective alternative therapies for patients with end-stage renal disease,increasingly draws international attention.And peritoneal fibrosis has been a hotspot in this field.Our team previously found that high glucose can induce increased expression of galectin-1(Gal-1)which participates in epithelialmesenchymal transition(EMT)in peritoneal mesenchymal cells.However,the specific regulatory mechanism of Gal-1 involvement in peritoneal fibrosis is still unknown.Some studies have proposed that Gal-1 as a Hypoxia reactive protein may be regulated by Hypoxia inducible factor 1alpha(HIF-1α).Therefore,the purpose of this study was to investigate whether Gal-1 is regulated by HIF-1α in the occurrence and development of PD-related peritoneal fibrosis.Methods: 1.Overnight peritoneal effluent from under regular peritoneal dialysis patients up to the inclusion criteria were collected.According to the peritoneal dialysis duration,the patients were divided into short-term peritoneal dialysis group(peritoneal dialysis duration ≤6months)and long-term peritoneal dialysis group(peritoneal dialysis duration >6 months).The exfoliated mesenchymal cells extracted from peritoneal dialysis solution were precipitated for paraffin section,and immunohistochemistry and immunofluorescence staining were performed.The expressions of Galectin-1,HIF-1α and Fibronectin proteins were compared between the two groups.2.Human peritoneal mesenchymal cell line(Me T-5A)were cultured and treated with different concentrations of glucose(normal group,1.5%HG,2.5%HG,4.25%HG)and hyper osmic mannitol for 24 hours.Then we observed morphological changes and compared the protein expression changes of HIF-1α,Galectin-1,FN and CTGF between them.3.Different concentrations(2.5um,5u M,10 u M)of HIF-1αinhibitors(LW6)were applied to intervene Me T-5A cells under medium with 4.25% high glucose,and cells were collected to detect the protein expressions of HIF-1α,Gal-1 and fibrosis related proteins.According to the optimal intervention concentration,three experimental groups were designed: Control group(5.5mmol/ L glucose),high glucose group(HG:4.25% glucose)and LW6 intervention group(LW6+HG: 10 u M LW6+4.25%glucose),and cells were collected for detecting mRNA and protein expressions of HIF-1α,Gal-1 and fibrosis related proteins among three groups.Results: 1.The expressions of Gal-1 and FN in exfoliated peritoneal mesenchymal cells from long-term peritoneal dialysis group were significantly increased compared with that from short-term peritoneal dialysis group,and the differences were statistically significant(P<0.05).HIF-1α expression also increased slightly,but no statistical differences were observed.2.Compared with the control group,the protein expressions of FN,HIF-1α and Gal-1 were raised in Me T-5A cells treated with 2.5%and 4.25% glucose with statistical differences(P<0.05),while there were no significant differences between the mannitol group and the control group.3.The mRNA and protein expressions of Gal-1,HIF-1α,FN and CTGF in high glucose group were significantly increased compared with the control group.After LW6 intervention,the expression of FN mRNA in Me T-5A cells under medium with 4.25% high glucose was significantly decreased(P<0.05),and the protein expressions of Gal-1,HIF-1α,FN and CTGF were also significantly decreased(P<0.05).Conclusion: The expression of Gal-1 and FN in human peritoneal mesenchymal cells was increased with the prolongation of peritoneal dialysis.Gal-1 expression was also increased in Me T-5A cells after high glucose treatment,but it was down-regulated by inhibiting HIF-1α.The expression of FN and CTGF was similar.It suggested that gal-1 may participate in the development of fibrosis regulated by HIF-1α/ Gal-1pathway,and HIF-1α may become a new target for the prevention and treatment of peritoneal fibrosis. |
