ABSTRACT
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 .
ABSTRACT
Purpose To investigate the relations of THEM4/Akt expression and extracellular matrix deposit in kidney of diabetic mice. Methods Diabetic mice models were successfully established by intraperitoneally injected STZ. Both normal control mice and diabetic mice were raised for 8 week until they were sacrificed. Western blot, immunohistochemistry and realtime PCR were used to detect the expression of THEM4, phospho-Akt (Ser 473), TGF-β1, a-SMA, Col Ш, FN protein and THEM4 mRNA in the kidneys of normal mice and diabetic mice. Results Compared to normal control mice, THEM4 expression decreased by 37.7％ followed by 3.66, 1.29 2.33, 1.99 and 2.82 times increased of phospho-Akt (Ser473), TGF-β1, a-SMA, Col Ш and FN in kidney of diabetes mellitus. Extracellular matrix accumulation was found in renal interstitial region of diabetic mice. Conclusion The decreased THEM4 might cause extracellular matrix deposit in kidney of diabetic mice by upregulating the phosphorylation of Akt and TGF-β1, α-SMA expression in diabetic mice.
ABSTRACT
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.