Transplantation Of Human Amniotic Mesenchymal Stem Cells Influence Acute Lung Injury In Rats By Sodium Channels Expression

Objective: To identify the transplantation of human amniotic mesenchymal stem cells(hAMSCs)influence on epithelial Na+ channels(ENaC)expression in rats with lipopolysaccharide(LPS)-induced acute lung injury(ALI)and investigate the relevant mechanism of h AMSCs intervention in ALI and provide new treatment ideas for ALI.Methods:In this study,84 healthy male Sprague-Dawley(SD)rats randomly assigned to the following groups: Normal saline control group(N group),h AMSCs control group(NH group),h AMSCs control group(NH group),h AMSCs control group(NH group)(n=4,21 per each group)..N group were injected with 0.25 ml normal saline by sublingually and injected with 0.25 ml normal saline after 2 hours by tail vein.NH group were injected with 0.25 ml normal saline by sublingually and injected with 250μl(1×10~4/μl)DAPI-labeled h AMSCs after2 hours by tail vein.ALI group were injected with LPS(4mg/kg)by sublingually and injected with 0.25 ml normal saline after 2 hours by tail vein.LH group were injected with LPS(4mg/kg)by sublingually and injected with 250μl(1×10~4/μl)DAPI-labeled h AMSCs after 2 hours by tail vein.Each group was divided into 3 sub-groups respectively: 6 hour group,12 hour group and 72 hour group..Seven rats were killed randomly at each group.In the NH and LH groups,the transplantation of h AMSCs in the lung tissue was observed under a fluorescence microscope.The levels of IL-1,IL-10 and TNF α in the broncho alveolar lavage fluid(BALF)of 84 rats were detected by enzyme-linked immunosorbent assay(ELISA).The lung tissue wet-to-dry ratio(W/D)was measured by thermal drying method.The pathological morphology of lung tissue in each group were observed under a microscope after HE staining.Protein expression of ENaC subunits(ENaC α,ENaC β,ENaC γ)in each group were detected by immunohistochemistry(IHC).The expression levels of ENaC subunits(ENaC α,ENaC β,ENaC γ)in each group were detected by Western blot.Results: The NH and LH group had blue fluorescently labeled h AMSCs around the alveoli under a fluorescence microscope,the LH group colonized more and the NH group colonized less,indicated that h AMSCs could be homing to the damaged lung tissue.There were no significant difference in lung tissue pathological scores,W/D,the level of IL-1,IL-10,TNF-αin BALF,the expression levels of ENaC α,ENaC β and ENaC γ between the NH group and N group at 6,12,and 72 hours(P>0.05).Compared N group,ALI group and LH group,lung tissue pathological scores,W/D,the levels of IL-1,IL-10,TNF-α in the ALI group and LH group were higher than N group and the expression levels of ENaC α,ENaC β and ENaC γ in the ALI group and LH group were lower than N group,the differences were statistically significant(P<0.05).Compared LH group and ALI group at the same time,the lung tissue inflammation infiltration pathological scores,W/D,the levels of IL-1,IL-10,TNF-α in the LH group were lower than ALI group and the expression levels of ENaC α,ENaC β and ENaC γin the LH group were higher than ALI group(P<0.05).Compared the 6 hour group and 12 hour group in the ALI group,there were no significant difference in the lung tissue inflammation infiltration pathological scores,W/D,the levels of IL-1,IL-10,TNF-α in BALF,the expression levels of ENaC α,ENaC β and ENaC γ(P>0.05).Compared the 6 hour group and 72 hour group in the ALI group,the lung tissue inflammation infiltration pathological scores,W/D,the levels of IL-1,IL-10,TNF-α in the 72 hour group were lower than in the 6hour group and the expression levels of ENaC α,ENaC β and ENaC γ in the 72 hour group were higher than in the 6 hour group(P<0.05).Compared the 6 hour group and 12 hour group in the LH group,there were no significant difference in the lung tissue inflammation infiltration pathological scores,W/D,the levels of IL-1,IL-10,TNF-α in BALF,the expression levels of ENaC α,ENaC β and ENaC γ(P>0.05).Compared the 6 hour group and72 hour group in the LH group,the lung tissue inflammation infiltration pathological scores,W/D,the levels of IL-1,IL-10,TNF-α in the 72 hour group were lower than in the 6 hour group and the expression levels of ENaC α,ENaC β and ENaC γ in the 72 hour group were higher than in the 6 hour group(P<0.05).Conclusion: Intravenous transplantation of exogenous h AMSCs can be to homing to lung tissues in rats,especially in the ALI rats.h AMSCs intervention could inhibit the release of IL-1,IL-10 and TNF-α in ALI rats and up-regulate the expression levels of ENaC α,ENaC βand ENaC γ,enhance alveolar fluid clearance.h AMSCs might be reduce the damage of the ALI rat lung tissue.