Interaction between CD81 and NCC is associated with LPS induced preeclampsia

Abstract

CD81, a member of the tetraspain superfamily, is an important component in the pathogenesis of pregnancy. In order to determine whether there is a connection between CD81 and renal sodium transporters, we studied the interaction of CD81 and Na+‐Cl‐cotransporter (NCC) in vivo and in vitro. A rat model of pregnancy hypertension was built by injecting a small amount of lipopolysaccharide (LPS, 0.5μg/kg in 2ml saline) into the tail vein of pregnant rats on GD 5. On GD 18, BPs (SBP :99.9±1.4 vs 116.9±1.8, DBP :85.9±2.0 vs 94.4±1.8,mmHg, n=7/group) and urine protein (1185±35.0 vs 3550±158.0, μg/day, n=4/group) were higher in LPS ‐rats relative to vehicle‐rats while renal protein abundance of CD81 (186.7±20, % of vehiclel, n=4/group, same as below) and NCC (278.0±53) was increased. CD81 was colocalized and co‐immunoparticipated with NCC, not with NHE3, in rat kidney. The immunofluorescent staining of NCC and CD81 was located in the sub‐cellular membrane and cytoplasm. In order to further explore the relationship between renal CD81 and NCC, we treated mouse kidney distal tubule cells with LPS for 24h to construct an in vitro experimental model. The protein abundances of CD81, and NCC in mDCT cells were increased in the cell groups treated with LPS at concentration of 10, 20, 30 g/mL while LDH and CCK‐8 were not altered. The cd81‐siRNA (32nM) for 48 hrs totally deleted CD81 protein. It also decrease NCC protein(70.9±4.8) expression without changing NCC mRNA(124.9±14) and reversed the increase of NCC(126.0±5.2,86.9±8.8) induced by LPS(10μg/mL) for the last 24 hrs conforming the interaction of CD81 with NCC in vitro. Thus, the interaction between CD81 and NCC are determined in vivo and its role in preeclampsia remains to be studied in future.