To Investigate The Effect Of Insulin-mTOR Pathway On Adipogenic Differentiation Of Mouse White Preadipocytes

Research has shown that insulin signaling regulates adipogenic differentiation of subcutaneous white preadipocytes derived from animals by affecting the transport efficiency of m TOR and GLUT-4 pathway.Our previous data show that mTOR pathway is of importance to the regulation of adipogenic differentiation of preadipocytes by mTOR signaling.In order to further study the molecular mechanism of insulin-mTOR signaling pathway in the course of regulating preadipocyte differentiation in vitro,we synchronized the white preadipocytes obtained from Leprdb/db obese and WT non-obese mice for 24 h and then divided the cells into the following 4 groups,respectively: adipogenic induction group,induction plus mTORC1 inhibitor(A-769662)group,induction plus GLUT-4 inhibitor(episesamin)group,and induction plus both mTORC1 and GLUT-4 inhibitors group.1.mTORC1 inhibition groups(1)In the cells obtained from Leprdb/db mice,the adipogenesis rate of preadipocytes decreased by(50.32±3.17)%;the gene expression of m TOR have no significant change,however,the protein expression of p-mTOR decreased by(69.13±4.26)%;the gene expression and protein expression of GLUT-4 have no significant change;the gene expression of PPARγ2 decreased by(74.62±4.48)%,the protein expression of PPARγ2decreased by(61.52±2.28)%.(2)In the cells obtained from WT mice,the adipogenesis rate of preadipocytes decreased by(60.17±3.45)%;the gene expression of m TOR have no significant change,however,the protein expression of p-mTOR decreased by(66.22±4.66)%;the gene expression and protein expression of GLUT-4 have no significant change;the gene expression of PPARγ2 decreased by(68.73±4.87)%,the protein expression of PPARγ2decreased by(71.68±2.12)%.2.GLUT-4 inhibition groups(1)In the cells obtained from Leprdb/db mice,the adipogenesis rate of preadipocytesdecreased by(30.44±2.21)%;the gene expression and protein expression of mTOR have no significant change;the gene expression and protein expression of GLUT-4 increased by(98.26±5.56)%,however,the protein expression of GLUT-4 decreased by(70.41±3.57)%;the gene expression of PPARγ2 decreased by(42.44±4.10)%,the protein expression of PPARγ2decreased by(46.24±2.99)%.(2)In the cells obtained from WT mice,the adipogenesis rate of preadipocytes decreased by(35.43±2.72)%;the gene expression and protein expression of mTOR have no significant change;the gene expression and protein expression of GLUT-4 increased by(88.11±4.43)%,however,the protein expression of GLUT-4 decreased by(64.57±3.23)%;the gene expression of PPARγ2 decreased by(48.62±4.17)%,the protein expression of PPARγ2 decreased by(49.35±3.54)%.3.Both mTORC1 and GLUT-4 inhibition groups(1)In the cells obtained from Leprdb/db mice,the adipogenesis rate of preadipocytes decreased by(70.41±3.17)%;the gene expression of m TOR have no significant change,however,the protein expression of p-mTOR decreased by(72.06±2.28)%;the gene expression and protein expression of GLUT-4 increased by(102.31±4.46)%,however,the protein expression of GLUT-4 decreased by(71.43±3.68)%;the gene expression of PPARγ2decreased by(78.53±5.06)%,the protein expression of PPARγ2 decreased by(84.48±2.30)%.(2)In the cells obtained from WT mice,the adipogenesis rate of preadipocytes decreased by(70.75±3.17)%;the gene expression of mTOR have no significant change,however,the protein expression of p-mTOR decreased by(63.46±4.33)%;the gene expression and protein expression of GLUT-4 increased by(87.02±5.54)%,however,the protein expression of GLUT-4 decreased by(62.83±4.16)%;the gene expression of PPARγ2 decreased by(73.31±4.25)%,the protein expression of PPARγ2 decreased by(76.56±3.65)%.Our results showed that insulin signaling regulates preadipocyte adipogenesis in mice mainly by affecting the mTOR signaling pathway.Moreover,the mTOR signaling pathway play a more important role in the mice of WT.