Diosgenin present in fenugreek improves glucose metabolism by promoting adipocyte differentiation and inhibiting inflammation in adipose tissues.
In obesity, adipocyte hypertrophy and chronic inflammation in adipose tissues cause insulin resistance and type-2 diabetes. Trigonella foenum-graecum (fenugreek) can ameliorate hyperglycemia and diabetes. However, the effects of fenugreek on adipocyte size and inflammation in adipose tissues have not been demonstrated. In this study, we determined the effects of fenugreek on adipocyte size and inflammation in adipose tissues in diabetic obese KK-Ay mice, and identified the active substance in fenugreek. Treatment of KK-Ay mice with a high fat diet supplemented with 2% fenugreek ameliorated diabetes. Moreover, fenugreek miniaturized the adipocytes and increased the mRNA expression levels of differentiation-related genes in adipose tissues. Fenugreek also inhibited macrophage infiltration into adipose tissues and decreased the mRNA expression levels of inflammatory genes. In addition, we identified diosgenin, a major aglycone of saponins in fenugreek to promote adipocyte differentiation and to inhibit expressions of several molecular candidates associated with inflammation in 3T3-L1 cells. These results suggest that fenugreek ameliorated diabetes by promoting adipocyte differentiation and inhibiting inflammation in adipose tissues, and its effects are mediated by diosgenin. Fenugreek containing diosgenin may be useful for ameliorating the glucose metabolic disorder associated with obesity.
Laboratory of Molecular Function of Food, Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto, Japan.
Taku
T
Uemura
Shizuka
S
Hirai
Noriko
N
Mizoguchi
Tsuyoshi
T
Goto
Joo-Yong
JY
Lee
Keiko
K
Taketani
Yuki
Y
Nakano
Jinji
J
Shono
Shohei
S
Hoshino
Nobuaki
N
Tsuge
Toshihiko
T
Narukami
Nobuyuki
N
Takahashi
Teruo
T
Kawada
D041721:3T3-L1 Cells; D017667:Adipocytes / Q000166:cytology* / Q000378:metabolism; D000273:Adipose Tissue / Q000187:drug effects*; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D002454:Cell Differentiation; D004144:Diosgenin / Q000494:pharmacology*; D004195:Disease Models, Animal; D005947:Glucose / Q000378:metabolism; D007249:Inflammation / Q000188:drug therapy*; D007333:Insulin Resistance; D008297:Male; D051379:Mice; D008820:Mice, Obese; D009765:Obesity / Q000628:therapy*; D008517:Phytotherapy; D010936:Plant Extracts / Q000494:pharmacology*; D012333:RNA, Messenger / Q000378:metabolism; D012503:Saponins / Q000032:analysis; D029910:Trigonella
D001786:Blood Glucose; D010936:Plant Extracts; D012333:RNA, Messenger; D012503:Saponins; C056164:fenugreek seed meal; D005947:Glucose; D004144:Diosgenin