Rapamycin reduces podocyte adhesion damage caused by sublytic C5b-9 via autophagy activation / 中华肾脏病杂志

ABSTRACT

Objective To determine the effect of rapamycin on sublytic C5b-9-induced podocyte adhesion damage,and whether autophagy is involved in this progression.Methods Sublytic complement C5b-9 stimulation was used in vitro.Autophagosomes were viewed using electron microscopy.Western blotting was used to measure the change of autophagy-related markers.Attachment assay was used to assess the adhesion of podocyte.Confocal microscopy was used to explore the expression patterns of cytoskeletal protein F-actin.Flow cytometry was used to measure the level of adhesion-associated protein integrin α3.Results (1) For ensuring sublytic complement injury,the maximal amounts of anti-podocyte antiserum and 160×-diluted normal human serum were used without inducing cell lysis (defined as ＞ 5％ LDH release).(2) Sublytic C5b-9 promoted autophagy in podocyte in vitro.The proautophagic effect of sublytic C5b-9 manifested in the form of accumulated autophagosomes and enhanced expression of LC3-lⅡ.(3) Inhibition of autophagy by 3-methyadenine enhanced the effect of sublytic C5b-9-induced podocyte injury,including serious cytoskeleton damage and markedly reduced adhesion of podocyte.(4) Rapamycin treatment significantly improved the above lesions.(5) Rapamycin enhanced autophagy induced by sublytic C5b-9 in podocyte.Conclusions In summary,rapamycin can improve sublytic CSb-9-induced podocyte adhesion damage by appropriate autophagy activation.These findings provide important information for the development of appropriate protocols for the application of mTOR (mammalian target of rapamycin) inhibitors in podocytopathy.