Institute of Pharmaceutical Science and Technology, College of Health Science, Central Taiwan University of Science and Technology, No. 666, Buzih Road, Beitun Road, Beitun District, Taichung City 40601, Taiwan, ROC.
Phytother Res. 2010 Dec;24(12):1769-80. doi: 10.1002/ptr.3143.
The effect of Eriobotrya japonica Lindl. (loquat) on insulin resistance was examined in mice fed a high-fat (HF) diet. First, the mice were divided randomly into two groups: the control (CON) group was fed a low-fat diet, whereas the experimental group was fed with a 45% HF diet for 10 weeks. After 6 weeks of induction, the HF group was subdivided into five groups and was given orally loquat or not for 4 weeks afterward. It was demonstrated that loquat was effective in ameliorating the HF diet-induced hyperglycemia, hyperleptinemia, hyperinsulinemia and hypertriglyceridemia, as well as in decreasing the levels of free fatty acid (FFA), but increasing the adipose PPARγ (peroxisomal proliferator-activated receptor γ) and hepatic PPARα mRNA levels. Loquat significantly decreased the body weight gain, weights of white adipose tissue and visceral fat accompanying the suppressed leptin mRNA levels. Loquat not only suppressed the hepatic mRNA levels of enzymes involved in fatty acid and triacylglycerol synthesis and lowered the sterol regulatory element binding protein-1c (SREBP-1c) mRNA level, but also affected fatty acid oxidation enzyme levels. These regulations may contribute to triacylglycerol accumulation in white adipose tissue. The findings provide a nutritional basis for the use of loquat as a functional food factor that may have benefits for the prevention of hyperlipidemia and diabetes.
枇杷（Eriobotrya japonica Lindl.）对高脂肪（HF）饮食诱导的胰岛素抵抗的影响在小鼠中进行了研究。首先，将小鼠随机分为两组：对照组（CON）喂食低脂饮食，实验组喂食 45%HF 饮食 10 周。诱导 6 周后，HF 组再分为五组，随后 4 周给予枇杷或不给予枇杷口服。结果表明，枇杷可有效改善 HF 饮食诱导的高血糖、高瘦素血症、高胰岛素血症和高三酰甘油血症，并降低游离脂肪酸（FFA）水平，同时增加脂肪组织过氧化物酶体增殖物激活受体γ（PPARγ）和肝组织过氧化物酶体增殖物激活受体α（PPARα）mRNA 水平。枇杷还显著降低了体重增加、白色脂肪组织和内脏脂肪的重量，同时降低了瘦素 mRNA 水平。枇杷不仅抑制了参与脂肪酸和三酰甘油合成的酶的肝 mRNA 水平，降低了固醇调节元件结合蛋白-1c（SREBP-1c）mRNA 水平，还影响了脂肪酸氧化酶水平。这些调节可能有助于三酰甘油在白色脂肪组织中的积累。这些发现为将枇杷作为功能性食品因子用于预防高血脂和糖尿病提供了营养基础。
