Zeynep Osar

Fenofibrate treatment is associated with better glycemic control and lower serum leptin and insulin levels in type 2 diabetic patients with hypertriglyceridemia

Background: Hertriglyceridemia is commonly encountered in type 2 diabetic patients. Fibrates are a group of drugs that efficiently decrease triglycerides, increase HDL, and improve the prognosis in both diabetic and nondiabetic patients. However, the effects of fibrates on glycemic control, blood pressure, fasting serum insulin, and leptin concentrations are not clear. The present study addresses the question of whether fenofibrate treatment in hypertriglyceridemic type 2 diabetic patients leads to changes in metabolic control, body mass index, leptin, free fatty acids, plasma insulin, and blood pressure. Methods: Thirty-one type 2 diabetic patients who had serum triglyceride levels between 250 and 400 mg/dl were included in the study. They were given 250 mg/day fenofibrate once daily for 3 months. Antidiabetic and antihypertensive treatments were kept unchanged throughout the study. Results: Fenofibrate treatment resulted in better glycemic control, as evidenced by lower fasting and postprandial blood glucose and HbAlc, decreased fasting serum insulin and leptin levels, as well as a reduction in hypertrigyceridemia and serum free fatty acids, and an increase in HDL cholesterol. Blood pressure, body mass index, and LDL remained unchanged. Fenofibrate was well tolerated in all patients. Conclusion: Fenofibrate treatment in hypertriglyceridemic type 2 diabetic patients is beneficial not only in terms of lipid profile, but also for glycemic control and insulin resistance.

Nicotinamide Effects Oxidative Burst Activity of Neutrophils in Patients with Poorly Controlled Type 2 Diabetes Mellitus

Neutrophil functions are impaired in patients with diabetes mellitus. Bacterial phagocytosis and oxidative burst activity are reduced at high glucose concentrations in diabetic patients. Defects in neutrophil oxidative burst capacity are of multifactorial origin in diabetes mellitus and correlate with glucose levels. It has been reported that neutrophil NADPH oxidase activity is impaired and superoxide production is reduced in diabetic patients with or without any infections. Nicotinamide is a vitamin B3 derivative and a NAD precursor with immunomodulatory effects. In vitro studies demonstrated that nicotinamide increases NAD and NADH content of beta cells. The authors hypothesized that nicotinamide may restore the impaired oxidative burst capacity of neutrophils in diabetic patients by increasing the NADH content as an electron donor and possibly through NADPH oxidase activity of the cell. In order to test the hypothesis, this placebo-controlled and open study was designed to evaluate neutrophil functions in infection-free poorly controlled type 2 diabetic patients as compared to healthy subjects and assess the effects of nicotinamide on neutrophil phagocytosis as well as oxidative burst activity. Thirty patients with type 2 diabetes mellitus were enrolled in the study. Sixteen were females and 14 were males, with a mean age 58 ± 10. All patients were on sulphonylurea treatment and their hemoglobin A1c (HbA1c) levels were above 7.5%. The control group consisted of 10 voluntary healthy subjects. Diabetic and control subjects were not significantly different in terms of age, body mass index (BMI), leucocyte and neutrophil counts, C-reactive protein (CRP) level, and erythrocyte sedimentation rate (ESR), but HbA1c and fasting glucose levels were significantly higher in patients with diabetes mellitus. Phagocytic activity and respiratory burst indexes were measured by flow cytometric analyses as previously described by Rothe and Valet (Methods Enzyml., 233, 539–548, 1994) and compared in diabetic subjects and healthy controls. Diabetic patients were grouped to receive either 50 mg/kg oral nicotinamide (n = 15) or placebo (n = 15) for a period of 1 month. The 2 groups did not differ in terms of treatment, frequency of hypertension, BMI, diabetes duration, age, fasting plasma glucose (FPG), HbA1c, CRP, ESR, polymorphonuclear leukocyte (PNL) and neutrophil counts. Neutrophil functions were reassessed after the treatment period. Phagocytic activity represented as indexes were lower in diabetic patients when compared to healthy subjects, but the differences were not statistically significant (P > .05). Patients with diabetes mellitus had significantly lower oxidative burst indexes when compared to healthy controls (P values < .05). In diabetic patients, a negative correlation between neutrophil functions and HbA1c was found which was not statistically significant (P values > .05). Phagocytic indexes were similar in nicotinamide and placebo groups after treatment period (P > .05). But oxidative burst activity in patients receiving nicotinamide was greater when compared with placebo and the difference was statistically significant at 30 and 45 minutes (P values .04 and .03). This effect of nicotinamide may be due to increased NADH content and NADPH oxidase activity of the cell, which needs to be further studied. Impaired neutrophil functions may aggravate various infections in patients with diabetes mellitus and blood glucose regulation is an important target of treatment to improve neutrophil functions. But nicotinamide treatment may help to improve prognosis in diabetic patients with severe infections.

Celiac disease in an adult Turkish population with type 1 diabetes mellitus.

Celiac disease is a frequent cause of morbidity among patients with type 1 diabetes mellitus. In this study our objective was to determine the prevalance of celiac diasease in a Turkish adult population with type 1 diabetes mellitus. Patients included 122 type 1 diabetes cases from adult diabetes clinic. Total IgA and IgA-antiendomysial antibody (AEA) assays were performed. Patients positive for IgA-AEA were asked to undergo small intestinal biopsy. Of the 122 patients, none was IgA deficient and 3 had positive IgA-AEA results (2.45%). All three of these patients had biopsies diagnostic of celiac disease. The body mass index (BMI) values of patients with positive AEA were significantly lower than normal (P = 0.024). Among the gastrointestinal complaints there was an association between early satiety and AEA positivity (P = 0.02). None of the other gastrointestinal complaints or age, duration of diabetes, glycosylated hemoglobin values, or insulin doses used were found to be related to AEA positivity. Celiac disease has a high prevalence among Turkish paients with type 1 diabetes mellitus. Screening for IgA-AEA during routine investigations of type 1 diabetic patients is important to prevent celiac-associated symptoms.

Effects of inhaled budesonide on insulin sensitivity in nondiabetic patients with asthma and chronic obstructive pulmonary disease.

In the study reported here, investigators explored the following: (1) the effects of inhaled corticosteroid (ICS) therapy on insulin sensitivity (IS) (the Homeostatic Model Assessment-Insulin Resistance [HOMA-IR] Index, which has never been used before in nondiabetic patients with asthma and chronic obstructive pulmonary disease [COPD], was used in this investigation); and (2) differences and similarities between asthma and COPD groups. A total of 12 patients with asthma and 6 with COPD who were not previously treated with oral corticosteroids or ICSs were treated with budesonide, 400 μg twice daily for 8 wk, via dry powder inhaler through the Aerolizer. Pretreatment and posttreatment values were recorded for forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), FEV1/FVC, C-reactive protein (CRP), blood glucose, serum insulin levels, area under the curve (AUC) for glucose and insulin in an oral glucose tolerance test (OGTT), and HOMA-IR Index. The trapezoid technique, the formula for HOMA-IR, and Wilkinson, Mann-Whitney U, and t tests were used. In the group of patients with asthma, posttreatment values for the HOMA-IR Index, glucose, and insulin at all time points during OGTT and AUC for glucose and AUC for insulin were not statistically different compared with pretreatment values. In patients with COPD who had been given ICS therapy, however, the second hour glucose level during OGTT increased significantly compared with pretreatment values (P=.46). Pretreatment and posttreatment second hour insulin values and posttreatment AUC for glucose were significantly higher in the COPD group than in the asthma group (P=.047,P=.044, andP=.031, respectively). A moderate positive correlation was noted between the percentage of difference in FEV1 and the change in HOMA-IR (pretreatment mean value of HOMA-IR±standard deviation [SD], 2.7±2.6) in asthmatic patients as the result of therapy (r=0.50,P=.138). Investigators concluded the following: (1) Differences in pathogenesis between asthma and COPD seem to offer the most plausible explanation for differences in carbohydrate metabolism achieved through ICS therapy; (2) the effect of an ICS on IS is associated not only with dose, treatment period, age, and body mass index (BMI) but also with the severity of initial mucosal inflammation; and (3) as a result of improvements in respiratory function noted after treatment had been given, IS was increased in asthmatic patients.

How important are the disturbances of lower gastrointestinal bowel habits in diabetic outpatients

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Does instantaneous blood glucose affect vibration perception threshold measurement using biothesiometer

Diabetic neuropathy is a common and troublesome complication of diabetes mellitus. Vibration sensation is a measure of large fiber nerve conduction, which is very commonly affected in diabetes. The present study addresses the question of whether vibration perception threshold (VPT) measurement using a biothesiometer is reproducible under different levels of blood glucose at different hours of the day. Seventy-five diabetic patients, 31 insulin-dependent diabetes mellitus and 44 non-insulin-dependent diabetes mellitus, with mean age 50.33+/-14.22 years (21-70 years) and diabetes duration of 14.3+/-10.6 years (1-60 years) were included in the study. Forty-one patients were male and 34 were female. In conclusion, VPT was found to be reproducible under different blood glucose levels at different hours of the day, which is affected only by the height of the patient.