Hao Chi-Long, Lin Hui-Li, Ke Liang-Yin, Yen Hsueh-Wei, Shen Kuo-Ping
Division of Cardiology, Department of Internal Medicine, Pingtung Christian Hospital, Pingtung, Taiwan.
Department of Food Science and Nutrition, Meiho University, Pingtung, Taiwan.
J Food Biochem. 2019 Mar;43(3):e12769. doi: 10.1111/jfbc.12769. Epub 2019 Jan 13.
This study examined the effect of pre-germinated brown rice extract (PGBRE), containing no dietary fibers, but γ-oryzanol, γ-aminobutyric acid (GABA), flavonoids, and anthocyanidin, on high-fat-diet (HFD)-induced metabolic syndrome. C57BL/6 mice were divided into five groups: regular diet, HFD, HFD with oral PGBRE 30, 300, or 600 mg/kg per day for 18 weeks. In the HFD group, higher body and liver weight gain, hyperglycemia, HbA1c, and insulin; higher TG, TC, LDL-C, non-HDL, atherosclerosis index, lower HDL, adiponectin in blood; higher TG in the liver; higher TG, bile acid in feces; and lower protein levels of AMP-activated protein kinase, insulin receptor, insulin receptor substrate-1, insulin receptor substrate-2, peroxisome proliferator-activated receptor-γ, phosphatidylinositol-3-kinase, Akt/PKB, glucose transporter-1, glucose transporter-4, glucokinase in the skeletal muscle; lower glucagon-like peptide 1 (GLP-1) in the intestine; higher sterol regulatory element-binding protein-1 (SREBP-1), stearoyl-CoA desaturase 1 (SCD-1), fatty acid synthase (FAS), 3-hydroxy-3-methylglutaryl-CoA reductase, proprotein convertase subtilisin/kexin type 9 (PCSK9), and lower PPAR-α, low-density lipoprotein receptor, cholesterol-7α-hydroxylase in the liver; higher SREBP-1, SCD-1, FAS, and lower PPAR-α, adiponectin in the adipose tissue were found. In HFD + PGBRE groups, the above biochemical parameters were improved. PRACTICAL APPLICATIONS: According to the results, we suggested that dietary fibers played a minor role in this study. Extract of PGBR, excluding dietary fiber, showed beneficial activity to ameliorate metabolic syndrome. γ-oryzanol, GABA, flavonoids, and anthocyanidin in PGBRE can inhibit HFD-induced metabolic syndrome and we demonstrated clearly its action mechanisms. This is the first report to examine the relation between PGBRE, GLP-1, and PCSK9. Taken together, PGBRE can potentially be used to develop a good supplement to control metabolic syndrome.
本研究检测了不含膳食纤维，但含有γ-谷维素、γ-氨基丁酸（GABA）、黄酮类化合物和花青素的预发芽糙米提取物（PGBRE）对高脂饮食（HFD）诱导的代谢综合征的影响。将C57BL/6小鼠分为五组：正常饮食组、高脂饮食组、高脂饮食且每天口服30、300或600mg/kg PGBRE的组，持续18周。在高脂饮食组中，发现体重和肝脏重量增加更多、血糖升高、糖化血红蛋白和胰岛素升高；血液中甘油三酯（TG）、总胆固醇（TC）、低密度脂蛋白胆固醇（LDL-C）、非高密度脂蛋白、动脉粥样硬化指数升高，高密度脂蛋白、脂联素降低；肝脏中TG升高；粪便中TG、胆汁酸升高；骨骼肌中AMP激活的蛋白激酶、胰岛素受体、胰岛素受体底物-1、胰岛素受体底物-2、过氧化物酶体增殖物激活受体-γ、磷脂酰肌醇-3激酶、Akt/蛋白激酶B、葡萄糖转运蛋白-1、葡萄糖转运蛋白-4、葡萄糖激酶的蛋白水平降低；肠道中胰高血糖素样肽1（GLP-1）降低；肝脏中固醇调节元件结合蛋白-1（SREBP-1）、硬脂酰辅酶A去饱和酶1（SCD-1）、脂肪酸合酶（FAS）、3-羟基-3-甲基戊二酰辅酶A还原酶、前蛋白转化酶枯草溶菌素/kexin 9型（PCSK9）升高，过氧化物酶体增殖物激活受体-α（PPAR-α）、低密度脂蛋白受体、胆固醇7α-羟化酶降低；脂肪组织中SREBP-1、SCD-1、FAS升高，PPAR-α、脂联素降低。在高脂饮食+PGBRE组中，上述生化参数得到改善。实际应用：根据结果，我们认为膳食纤维在本研究中起的作用较小。不含膳食纤维的PGBR提取物显示出改善代谢综合征的有益活性。PGBRE中的γ-谷维素、GABA、黄酮类化合物和花青素可抑制高脂饮食诱导的代谢综合征，我们明确证明了其作用机制。这是第一份研究PGBRE、GLP-1和PCSK9之间关系的报告。综上所述，PGBRE有可能被用于开发一种控制代谢综合征的优质补充剂。
