RESUMO
Aim To observe the effect of thioesterase superfamily member 4 ( THEM4 ) expression on extra-cellular matrix ( ECM ) accumulation in the kidney of diabetic mice .Methods For in vivo vector delivery experiment , male CD1 mice were randomly divided in-to four groups: normal control mice ( Control group ) , diabetic mice ( DM group ) , diabetic mice receiving pYr-ads-4-THEM4 vector ( DM+THEM4 vector ) and diabetic mice receiving pYr-adshuttle-4 vector ( DM+V vector ) .pYr-ads-4-THEM4 vector or pYr-adshuttle-4 vector ( 1 mg · kg -1 ) were mixed with TransIT-EE Hydrodynamic Delivery Solution from Mirus Co .and injected into tail vein once a week for four weeks after STZ injection.Four weeks later, mice were sacrificed and Western blot , immunohistochemistry and real-time PCR were used to detect the expression of phospho-Akt(Ser 473), THEM4, TGF-β1, α-SMA, Col Ⅲ, FN proteins and THEM4 mRNA in kidneys respectively . Results THEM4 decreased in kidney of diabetes mel-litus accompanied with increased phospho-Akt ( Ser 473), TGF-β1, α-SMA and ECM.The delivery of pYr-ads-4-THEM4 vector increased THEM4 expression and decreased phospho-Akt (Ser 473), TGF-β1, α-SMA and ECM deposit in kidneys of diabetic mice . Conclusion The up-regulation of THEM4 may pre-vent ECM deposit by inhibiting the phosphorylation of Akt and down-regulating the expression of TGF-β1 andα-SMA in kidneys of diabetic mice .
RESUMO
Aim To investigate the effect of thioester-ase superfamily member 4(THEM4)expression on col-lagen secretion in human renal proximal tubular epithe-lial cells (HKC)treated with high glucose. Methods In order to examine the direct effect of THEM4 ex-pression vector on PI3K/ Akt pathway and collagen se-cretion,pYr-ads-4-THEM4 expression vector was con-structed and transfected into the HKC with lipo-fectamine 2000 in vitro. HKC cells were randomly di-vided into four groups:normal glucose group (Con-trol),high glucose group (HG),high glucose plus pYr-ads-4-THEM4 vector group (HG + THEM4 vec-tor) and high glucose plus pYr-adshuttle-4 vector group (HG + V vector). After 48 h with HG stimula-tion,the cells were collected for extraction of protein and phospho-Akt (Ser 473),THEM4,TGF-β1 andα-SMA protein expression were examined by Western blot and immunofluorescence staining respectively. Col Ⅰ and Col Ⅲ were detected using the competitive sandwich ELISA kit according to the manufacturer's instructions. Results High glucose inhibited THEM4 expression,and induced increased phospho-Akt (Ser 473),TGF-β1,α-SMA and secreted ColⅠand secre-ted Col Ⅲ in HKC cells. Up-regulation of THEM4 re-versed high glucose-induced decreased THEM4,in-creased phospho-Akt (Ser 473),TGF-β1,α-SMA, secreted Col Ⅰ and secreted Col Ⅲ in HKC cells. Conclusion The up-regulation of THEM4 may de-crease Col Ⅰ and Col Ⅲ secretion by inhibiting the phosphorylation of Akt and down-regulating the expres-sion of TGF-β1 and α-SMA in high glucose-induced HKC cells.