Glucose-dependent insulin-releasing peptide [GIP] in patients with type 2 diabetes mellitus with and without autonomic neuropathy

This study was conducted to investigate the role of glucose-dependent insulin-releasing peptide or gastric inhibitory polypepetide [GIP] in the control of glycemic state in patients with type 2 diabetes mellitus in the presence and absence of autonomic neuropathy. Twenty patients with type 2 jiabetes mellitus and 10 healthy normal subjects were studied. The diabetic patients were divided into 2 equal groups: one group with autonomic neuropathy [AN] and the other without AN according to cardiovascular autonomic function tests. Patients and controls were subjected to clinical examination and determination of HbA[1c]%, fasting blood sugar and basal insulin level. One-hour after ingestion of standard mixed meal [50 gm carbohydrate and 8% amino acid in 400 ml water] blood samples were collected for determination of glucose, insulin, and GIP plasma levels. Insulin resistance index was calculated from the homeostasis model assessment equation [HOMA]. A significantly impaired postprandial GIP and insulin levels as well as their responses to the ingestion of the mixed meal in the type 2 diabetics with AN was observed compared to those without AN. Postprandial GIP level was found to be correlated negatively with postprandial glucose level [r=-0.54] and positively with postprandial insulin level [r=-0.45], P < 0.05 for all diabetic patients. In diabetic patients with AN, significant -negative correlations were detected between duration of diabetes and postprandial GIP level [r= -0.66], absolute GIP response [r= -0.74], as well as% GIP response [r=- 0.71] [P < /= 0.05 for all.]. GIP plays an important role in the physiologic control of postprandial glucose homeostasis. GIP responses were lower in the diabetics as a group compared with healthy subjects despite similar basal levels. Moreover, In diabetic patients with autonomic neuropathy, there was a delayed and impaired GIP response to the mixed meal. Their absolute and% GIP responses were significantly lower than those of control subjects and patients without autonomic neuropathy

effect of gralic on nitric oxide level in diabetic rats

The increase in number of diabetic patients motivated scientists to find new methods to control such disease. In the present study, the action of Garlic [Allium sativum] was studied on normal and streptozotocin [STZ]-induced diabetic rats. Experimental group included 60 male albino rats divided equally into control group, control group given oral daily dose of garlic [100 mg/kg B.wt] for 16 weeks, STZ-induced diabetic untreated group, and diabetic garlic-treated group included STZ-induced diabetic rats given the daily oral dose of the garlic for 16 weeks. Blood samples were collected for determination of blood glucose, nitric oxide [NO], malondialdehyde [MDA], and lipid profile [triglycerides [TG], cholesterol [C], high density lipoprotein-cholesterol [HDL-C], and low density lipoprotein-cholesterol [LDL-C]]. Supplementation of garlic to non-diabetic rats had produced no significant differences as regards any of the parameters including glucose, lipid profile, nitric oxide, and lipid peroxidation end product malondialdehyde [MDA] levels when compared with the control group. The diabetic rats showed significant elevation in serum glucose, NO, MDA, TG, C, and LDL-C. Concomitantly significant decrease in HDL-C was detected when compared with their corresponding values of controls. However, supplementation of garlic to the diabetic rats had shown a significant decrease in serum glucose, TG, C, LDL-C, NO, [and MDA] levels, while elevation in HDL-C level was detected. Thus, from the present study it is assumed that garlic treatment decreases the blood glucose level. Antioxidant garlic may protect B cells against toxic effect of ROS [reactive oxygen species] provoked due to hyperglycemia. This was indicated by the significant decrease of oxidative stress after garlic treatment in the studied group. It is concluded that garlic supplementation improves blood lipid profiles, strengthens blood oxidant potential, and causes significant reduction in blood glucose; NO; and MDA levels. These results suggest that garlic exerted antioxidant and antihyperglycemic effects