Cheng Hong Sheng, Yaw Hui Ping, Ton So Ha, Choy Siew Mei, Kong Joana Magdelene Xiao Fang, Abdul Kadir Khalid
School of Science, Monash University Malaysia, Selangor Darul Ehsan, Malaysia.
School of Science, Monash University Malaysia, Selangor Darul Ehsan, Malaysia.
Nutrition. 2016 Sep;32(9):995-1001. doi: 10.1016/j.nut.2016.02.002. Epub 2016 Mar 2.
To investigate the effects of glycyrrhizic acid supplementation on glucose and lipid metabolism in rodents consuming a high-fat, high-sucrose diet.
Twenty-four male, 8-week old Sprague Dawley rats with an initial weight of 160 to 200 g were randomised into three groups (n = 6 for each group): groups A (standard rat chow), B (high-fat, high-sucrose diet), and C (high-fat, high-sucrose diet + 100 mg/kg/d of glycyrrhizic acid via oral administration). The rats were treated accordingly for 4 wk. Glycaemic parameters, lipid profile, stress hormones, and adiponectin levels were measured after the treatment. Relative gene expressions of peroxisome proliferator-activated receptor α and γ, lipoprotein lipase as well as gluconeogenic enzymatic activities in different tissues were also determined.
Consumption of high-fat, high-sucrose diet triggered hyperglycaemia, insulin resistance, and dyslipidemia, which were effectively attenuated by supplementation with glycyrrhizic acid. Glycyrrhizic acid supplementation also effectively reduced circulating adrenaline, alleviated gluconeogenic enzymes overactivity, and promoted the upregulation of lipoprotein lipase expression in the cardiomyocytes and skeletal muscles. A high calorie diet also triggered hypoadiponectinaemia and suppression of peroxisome proliferator-activated receptor γ expression, which did not improve with glycyrrhizic acid treatment.
Supplementation with glycyrrhizic acid could alleviate high calorie diet-induced glucose and lipid metabolic dysregulations by reducing circulatory stress hormones, normalizing gluconeogenic enzyme activities, and elevating muscular lipid uptake. The beneficial effects of these bioactivities outweighed the adverse effects caused by diet-induced repression of peroxisome proliferator-activated receptor γ expression, resulting in the maintenance of lipid and glucose homeostasis.
研究补充甘草酸对食用高脂高糖饮食的啮齿动物糖脂代谢的影响。
将24只8周龄、初始体重为160至200克的雄性斯普拉格-道利大鼠随机分为三组（每组n = 6）：A组（标准大鼠饲料）、B组（高脂高糖饮食）和C组（高脂高糖饮食 + 通过口服给予100毫克/千克/天的甘草酸）。大鼠相应处理4周。处理后测量血糖参数、血脂谱、应激激素和脂联素水平。还测定了不同组织中过氧化物酶体增殖物激活受体α和γ、脂蛋白脂肪酶的相对基因表达以及糖异生酶活性。
食用高脂高糖饮食引发高血糖、胰岛素抵抗和血脂异常，补充甘草酸可有效减轻这些症状。补充甘草酸还能有效降低循环肾上腺素水平，减轻糖异生酶活性过高的情况，并促进心肌细胞和骨骼肌中脂蛋白脂肪酶表达的上调。高热量饮食还引发低脂联素血症和过氧化物酶体增殖物激活受体γ表达的抑制，甘草酸治疗对此无改善作用。
补充甘草酸可通过降低循环应激激素、使糖异生酶活性正常化以及提高肌肉脂质摄取来减轻高热量饮食诱导的糖脂代谢失调。这些生物活性的有益作用超过了饮食诱导的过氧化物酶体增殖物激活受体γ表达受抑制所带来的不利影响，从而维持了脂质和葡萄糖稳态。
