Effects of flavonoid-rich Chinese bayberry (Morella rubra Sieb. et Zucc.) fruit extract on regulating glucose and lipid metabolism in diabetic KK-A(y) mice.
In the present study, male diabetic KK-A(y) mice were used to investigate the antidiabetic effect of bayberry fruit extract (BFE, 200 mg kg(-1)) by gavage for 5 weeks. BFE significantly lowered fasting blood glucose, improved glucose tolerance and insulin sensitivity in KK-A(y) mice. It significantly reduced serum concentrations of glucose, lipids, inflammation, and liver function markers, including insulin, glucagon, leptin, total cholesterol, triglycerides, low density lipoprotein, interleukin-1β, and alanine transferase in KK-A(y) mice. Liver weight and liver lipid accumulation were also markedly reduced by BFE in mice. The hypoglycemic effect of BFE appeared to be partially mediated through the inhibition of hepatic gluconeogenesis, which was supported by the reduced PPARγ coactivator 1-alpha (PGC-1α) and phosphoenolpyruvate carboxykinase (PEPCK) mRNA expressions in the liver of KK-A(y) mice and by the decreased glucose production, increased glycolysis as well as the reduced gene expression levels of PGC-1α, PEPCK, and glucose-6-phosphatase (G6Pase) in HepG2 cells. Gene expressions of hepatic lipid metabolism and inflammatory markers were also down-regulated by BFE in the liver of KK-A(y) mice. Furthermore, BFE promoted hepatic phosphorylation of AMPKα (Thr172) both in vivo and in vitro. Therefore, the activation of the AMPK pathway may play an important role in the antidiabetic effects of BFE, and red Chinese bayberry fruits may be an effective dietary food for the management of type 2 diabetes and its complications.
Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology, Zhejiang University, Zijingang Campus, Hangzhou, 310058, PR China. xianli@zju.edu.cn and Laboratory of Fruit Quality Biology, Zhejiang University, Zijingang Campus, Hangzhou, 310058, PR China.
Xianan
X
Zhang
Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology, Zhejiang University, Zijingang Campus, Hangzhou, 310058, PR China. xianli@zju.edu.cn and Laboratory of Fruit Quality Biology, Zhejiang University, Zijingang Campus, Hangzhou, 310058, PR China.
Qiang
Q
Lv
Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology, Zhejiang University, Zijingang Campus, Hangzhou, 310058, PR China. xianli@zju.edu.cn and Laboratory of Fruit Quality Biology, Zhejiang University, Zijingang Campus, Hangzhou, 310058, PR China.
Sheng
S
Jia
Laboratory Animal Centre of Zhejiang University, Hangzhou, 310058, China.
Yanhong
Y
Chen
Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology, Zhejiang University, Zijingang Campus, Hangzhou, 310058, PR China. xianli@zju.edu.cn and Laboratory of Fruit Quality Biology, Zhejiang University, Zijingang Campus, Hangzhou, 310058, PR China.
Chongde
C
Sun
Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology, Zhejiang University, Zijingang Campus, Hangzhou, 310058, PR China. xianli@zju.edu.cn and Laboratory of Fruit Quality Biology, Zhejiang University, Zijingang Campus, Hangzhou, 310058, PR China.
Xian
X
Li
Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology, Zhejiang University, Zijingang Campus, Hangzhou, 310058, PR China. xianli@zju.edu.cn and Laboratory of Fruit Quality Biology, Zhejiang University, Zijingang Campus, Hangzhou, 310058, PR China.
Kunsong
K
Chen
D000818:Animals; D015415:Biomarkers / Q000097:blood; D001786:Blood Glucose / Q000378:metabolism*; D003924:Diabetes Mellitus, Type 2 / Q000188:drug therapy; D005419:Flavonoids / Q000494:pharmacology*; D005638:Fruit / Q000737:chemistry*; D005934:Glucagon / Q000097:blood; D005952:Glucose-6-Phosphatase / Q000235:genetics / Q000378:metabolism; D005979:Glutathione Peroxidase / Q000235:genetics / Q000378:metabolism; D056945:Hep G2 Cells; D006801:Humans; D007004:Hypoglycemic Agents / Q000494:pharmacology; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance; D020738:Leptin / Q000097:blood; D050356:Lipid Metabolism / Q000187:drug effects*; D008055:Lipids / Q000097:blood; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D051379:Mice; D031641:Myrica / Q000737:chemistry*; D009929:Organ Size / Q000187:drug effects; D010936:Plant Extracts / Q000494:pharmacology*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism
D015415:Biomarkers; D001786:Blood Glucose; D005419:Flavonoids; D007004:Hypoglycemic Agents; D007328:Insulin; D020738:Leptin; D008055:Lipids; D010936:Plant Extracts; D014157:Transcription Factors; C111264:peroxisome-proliferator-activated receptor-gamma coactivator-1; C014149:phosphoenolpyruvate carboxykinase ferroactivator protein, rat; D005934:Glucagon; D005979:Glutathione Peroxidase; D005952:Glucose-6-Phosphatase