[Effect of berberine on the differentiation of adipocyte].
OBJECTIVE
To observe the effect of berberine on the differentiation of 3T3-L1 preadipocytes into adipocytes and to elucidate its mechanism.


METHODS
3T3-L1 preadipocytes were cultured and then divided into 7 groups into whose media were added berberine of the concentrations of 0, 0.1, 1, 10, and 100 micro mol/L, 100 nmol/Linsulin, and 10 micro mol/L berberine + 100 nmol/L insulin. The proliferation of 3T3-L1 preadipocytes was detected by MTT method. The accumulation of lipid in the cytoplasm of differentiated adipocytes was observed by oil red O staining. The peroxisome proliferation activated receptor gamma2 (PPARgamma2) mRNA and protein were detected by RT-PCR and Western blotting respectively.


RESULTS
MTT method showed that the absorbance at 570 nm of 3T3-L1 preadipocytes increased by 17% (P < 0.01), 36% (P < 0.001), and 22% (P < 0.05) in the groups of 1, 10, and 100 micro mol/L berberine, by 53% (P < 0.0001)in the group of 100 nmol/L insulin, and by 66% in the group of 10 micro mol/L berberine + 100 nmol/L insulin. There were less and smaller lipid droplets in the 3T3-L1 adipocytes treated with berberine as compared with the untreated control cells and only 10% - 20% of the treated cells displayed big lipid drops. RT-PCR showed that berberine significantly reduced the expression of PPARgamma2 mRNA by 48% (P < 0.01) in the course of 3T3-L1 adipocyte differentiation. Western blotting showed that berberine inhibited the expression of PPARgamma2 protein.


CONCLUSIONS
Berberine promotes the proliferation of 3T3-L1 preadipocytes, decreases the accumulation of lipid drops therein, and inhibits the terminal differentiation of adipocyte, which may be associated with its effect on decreasing the expression of PPARgamma2 mRNA and protein, suggesting that berberine has advantages in the treatment of obesity patients with type 2 diabetes.
Zhou
Li-bin
LB
Shanghai Institute of Endocrinology, Ruijin Hospital, Shanghai Second Medical University, Shanghai 200025, China.
Chen
Ming-dao
MD
Wang
Xiao
X
Song
Huai-dong
HD
Yang
Ying
Y
Tang
Jin-feng
JF
Li
Feng-ying
FY
Xu
Man-yin
MY
Chen
Jia-lun
JL
D041721:3T3-L1 Cells; D017667:Adipocytes / Q000166:cytology*; D000818:Animals; D001599:Berberine / Q000494:pharmacology*; D002454:Cell Differentiation / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D051379:Mice; D012333:RNA, Messenger / Q000032:analysis; D018160:Receptors, Cytoplasmic and Nuclear / Q000032:analysis / Q000235:genetics; D013234:Stem Cells / Q000166:cytology; D014157:Transcription Factors / Q000032:analysis / Q000235:genetics
D012333:RNA, Messenger; D018160:Receptors, Cytoplasmic and Nuclear; D014157:Transcription Factors; D001599:Berberine