AIM To investigate the effects of tectorigenin on preadipocyte differentiation and the possible mechanism.METHODS CCK8 method was used to detect the effects of tectorigenin on 3T3-L1 cell viability.After 2 days contact inhibition(Day 0 of differentiation),the cells were exposed to inducer and tectorigenin of different concentrations(0,10,20,40,60 μmol/L),in contrast to those of the control group with no inducer use.On the 9th day of differentiation,the cells had their lipid droplets observed by oil red O staining;their levels of TG and NEFA detected by biochemical kit;their protein expressions of PPARγ,C/EBPα,perilipin-1,ADFP,AMPKα and p-AMPKα detected by Western blot;and their mRNA expressions of Adiponectin,FABP4,FAS and Acly detected by RT-qPCR.RESULTS Tectorigenin concentration of 60 μmol/L or lower levels left no impact upon the cell viability(P>0.05).Compared with the model group with induced differentiation,the groups intervened with tectorigenin administration displayed decreased formation of lipid droplets;lower levels of TG and NEFA(P<0.01);decreased protein expressions of C/EBPα,PPAR γ,perilipin-1 and ADFP(P<0.01);increased protein expressions of AMPKα and p-AMPKα(P<0.01);and decreased mRNA expressions of Adiponectin,FABP4,FAS and Acly(P<0.01).CONCLUSION Tectorigenin inhibits preadipocyte differentiation into mature adipocytes,which may be related to its efficacy in the regulation of C/EBPα,PPARγ,AMPKα and p-AMPKα.