The Generation Of Glucose Wild Wild Rice Index And Its Regulatory Lipotoxicity Improve Insulin Resistance In Rats

Objectives:(1) Understand the glycemic index of Chinese wild rice and provide a reference basis for diabetes patients dietary guidance application.(2) To discuss the function of Chinese wild rice improving lipid toxicity and insulin resistance and to provide new theoretical basis for discovering new targets and using Chinese wild rice for nutritional interventions to prevent and delay the T2DM,we observe the influences of Chinese wild rice on blood lipid, blood sugar of the insulin resistance rats induced by high-fat diet,the content of inflammatory factor and adipocyte factor, the GSIS function of rats Islet beta cells and ascertain the gene expression of PPARa, PPARy, IRS-1, IRS-2and NF-κB in the liver or adipose tissues.Methods:(1)Extract venous blood in the early morning after8subjects are on empty,then respectively t extrac the15、30、45、60、90、120min venous blood after they taking oral glucose solution and eating cooked wild rice, using Jenkins and Wolever formula, plot AUC graph and make calculation analysis the glycemic index GI of Chinese wild rice according to the ratio of blood glucose area curve.(2)50SD rats were randomly divided into5groups:the negative control group, the insulin resistance model group,the high dose of wild rice group(G), the low dose of wild rice group (D) and the rice-flour group according to the level of blood sugar after one week of acclimatization period by feeding on standard chow diets. Blood sampling by docking and separating out blood serum by centrifugalizing,determine the total cholesterol (TC), triglyceride(TG), high-density lipoprotein cholesterol (HDL-C),low density lipoprotein cholesterol (LDL-C), fasting plasma glucose (FPG), fasting insulin (INS).(3) On the basis of ANI-93M animal feed formula, by appropriately adjusting the proportion of protein and sugar,increasing the content of saturated fatty acid and cholesterol, at the same time instead of sucrose and starch in high fat feed with rice flour and wild rice by certain proportion to make high dose of wild rice mixture group, low dose of wild rice and rice flour group feed. The negative control diet is based on the AIN-93M formulation and the other four groups were given high fat feed, high dose of wild rice feed, the low dose of wild rice feed and rice flour feed.(4) Continuous feeding8weeks according to the above feed supply, at the start, the4th, the6th and the8th of the feeding period, blood samples were taken from the tail vein or the abdominal aorta of fasted rats(12-14h). Serum total cholesterol(TC), triglyceride(TG), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), fasting blood glucose (FPG), free fatty acids(FFAs), glycosylated hemoglobin (GHbAlc), Glucagon (GC), Hypersensitive c-reactive protein (hs-CRP), tumor necrosis factor (TNF alpha), interleukin-6(il-6),adiponectin(ADP), leptin (Lep) and resistance (Res) were measured.At the end of the experiment, the rat organs such as the liver,the spleen, the fat of kidney and testicle were collected and weighted,and the histological pathology changes of rats’hepatocytes were measured. Calculatethe indexes of insulin resistance (HOMA-IR) and sensitive index (ISI) of rats.(5)Cultivating rat islet after being separates and purificatedby dextran density gradient centrifugation respectively in the glucose concentrations of5.5mmol/L and27.0mmol/L RPMI1640medium for48h, collect culture solution and islet beta cells to determinate GSIS and the content of insulin in the cell.(6)Gene expressions of PPARα、IRS-1、IRS-2、NF-κB in the liver tissueand PPARγ、IRS-1、IRS-2、NF-κB in the adipose tissue were determined by RT-PC method.Results:(1)The glycemic index of Chinese wild rice is53.72.(2) Animal experimental results show that the body weight and the lever of FPG、FINS、HOMA-IR, TC、TG, visceral fat mass and body fat ratio、FFAs、GHbAlc、GC, hs-CRP、TNF-α、IL-6、Lep、Res of high dose of wild rice group and low dose of wild rice rats compared with the insulin resistance model group and the rice flour group rats decline obviously (P<0.05) and the level of HDL-C、ADP and ISI increase obviously (P<0.05); High dose wild rice group, low dose of wild rice group and the negative control group have no significant difference (P>0.05), even the improvement to blood lipid and blood sugar of high dose of wild rice group is higher than low high dose of wild rice group; Rice flour group is close to the insulin resistance model group. The HE slices result of experiment rats displays that the wild rice group can significantly reduce the degree of rat liver fatty degeneration and inflammation and the improvement effect of high dose of wild rice group is better than the low dose of wild rice.(3) Compared with negative control group, the function of islet beta cell glucose stimulated insulin secretion GSIS of the insulin resistance model and rice flour group rat decreased obviously (P<0.05); The difference between high dose of wild rice group, low dose of wild rice and the negative control group is not significant (P>0.05); The GSIS function of high dose of wild rice is higher than the dose of wild rice group; Rice flour group is close to insulin resistance model.(4) The expression of PPARα、IRS-1、IRS-2in liver tissue of high dose of wild rice significantly increases (P<0.05); the expression of NF-κB decrease significantly (P<0.05); The expression of PPARγ、IRS-1、IRS-2in the adipose tissue significantly increases and the expression of NF-κB decrease significantly (P<0.05);The expression level between high dose of wild rice group, low dose of wild rice and negative control group had no significant difference (P>0.05).The expression level of rice flour is close to the insulin resistance model group (P>0.05).Conclusions:(1) Chinese wild rice belongs to the low blood sugar index of food.(2) Chinese wild rice has the function of improving the insulin resistance of rats induced by high-fat diet. Its possible mechanism is by cutting the content of free fatty acids, increasing insulin secretion function GSIS of rat islet beta cell, regulating the expression of fat factor and inflammatory cytokines,improving the function of the fat cells and immune cells, thereby slowing lipid toxicity to improve insulin resistance.