Oguz Kaan Unal

Effect of sitagliptin monotherapy on serum total ghrelin levels in people with type 2 diabetes.

AIM Sitagliptin is not associated with weight gain and has neutral effects on body weight. It is unclear whether sitagliptin treatment alters serum ghrelin levels in people with type 2 diabetes. METHODS Forty-four subjects with type 2 diabetes were randomly assigned to receive sitagliptin or medical nutrition therapy (MNT) for 12 weeks. Changes in anthropometric variables, glycemic control, insulin resistance, lipid parameters, and total ghrelin levels were evaluated at baseline and following 12 weeks of treatment. RESULTS Significant decreases in body weight and body mass index were observed over the entire study period in both treatment groups. Glycosylated hemoglobin and postprandial plasma glucose levels were statistically significant decreased in the groups receiving sitagliptin compared with baseline values (p=0.021 and p=0.021, respectively), while they were unchanged in the groups receiving MNT. There was a significant decrease in total ghrelin in the groups receiving sitagliptin (p=0.04) compared with baseline values but not in the groups receiving MNT (p=0.46) at the end of the 12 weeks. CONCLUSIONS In this study of patients with type 2 diabetes, treatment with sitagliptin was associated with a significant decrease in serum ghrelin levels. These results suggest that the neutral effect of sitagliptin on weight might be associated with the suppression of fasting serum ghrelin levels.

A rare cause of hypoglycemia in a type 2 diabetic patient: insulinoma

Recurrent episodes of hypoglycemia in patients with diabetes are often associated with the ongoing treatment regimen. However, despite changes in treatment modalities, assessment of the causes of hypoglycemia in nondiabetic patients in the presence of severe and recurrent hypoglycemia is very important. The treatment that had been provided for 6 years in a 67-year-old female patient with type 2 diabetes mellitus was discontinued due to hypoglycemic episodes that presented for the previous 2 years. The patient experienced persistent hypoglycemia after cessation of the treatment and was hospitalized for further examination. Spontaneous hypoglycemia with a final diagnosis of insulinoma was established following histopathologic evaluation and was relieved postoperation. Insulinoma is rarely encountered as a cause of hypoglycemia in patients with type 2 diabetes. Insulin-secreting tumors should be considered where hypoglycemic episodes occur despite discontinuation of insulin and other antidiabetic treatment with endogenous hyperinsulinemia being noncompliant with the blood glycemic levels.

Effect of cycline D1 (CCND1) gene polymorphism on tumor formation and behavior in patients with prolactinoma

The objective of this study was to investigate the effect of G870A gene polymorphism of CCND1 on the formation and behavioral features of prolactinomas. One hundred and thirteen patients with prolactinoma and 108 age and gender matched control were included in the study. The patients were divided into two groups as noninvasive and invasive tumors. CCND1 G870A gene polymorphism was compared in patients/control and invasive/noninvasive groups. A and G allele frequencies were found as 41.7% and 58.3% in the controls, and 61.1% and 38.9% in the patients (p<0.01). Rates of G/G, G/A and A/A genotypes were found as 11.8%, 55.9% and 32.4% in the noninvasive group, and 15.6%, 44.4% and 40.0% in the invasive group, respectively. Differences between patient and control groups were significant but were not between invasive and noninvasive groups in terms of the allele frequencies and genotype distribution. Mean tumor size and serum levels of prolactin at the time of diagnosis and change in these values after the treatment were not found statistically significant in genotype subgroups. CCND1 G870A gene polymorphism may be an important factor in the early stages of the tumor formation. However, it did not affect the features of the tumor.

Comparison of efficacy and safety of once- versus twice-daily insulin detemir added on to oral antidiabetics in insulin-naive type 2 diabetes patients: 24-week, crossover, treat to target trial in a single center

AIM To compare once- versus twice-daily insulin detemir added on OADS therapy in insulin-naive type 2 diabetes patients in terms of efficacy and safety. METHODS An open-label study performed at a single center, comprised a randomized, crossover 24 week with insulin-naive type 2 diabetes patients. Insulin detemir was initiated with mean 0.12 U/kg in all patients (Group I once-daily, Group II twice-daily) and titrated for 24 week. RESULTS A total of 50 patients completed the study (Group I n:25, Group II n:25). With use of once- and twice-daily insulin, HbA1c values were decreased by 1.8% (±2.0) and 1.5% (±1.4) within the first 12 weeks (p<0.01), whereas increased by 0.21% (±0.7) and 0.14% (±0.8) in the second 12 weeks (p>0.05). The increases in the insulin doses were found as 0.22 U/kg and 0.35 U/kg with once- and twice-daily insulin use, respectively (p:0.04). Although minor hypoglycemic events were similar in both groups in the first 12 weeks, 2-fold increase was found in the patients shifting from once- to twice-daily dose. Within the first and second periods, the body weight of the patients was observed an increase of 0.4 and 1.6 kg with once-daily dose, whereas a decrease of 0.1 and 2.1 kg in the twice-daily dose, in the same period. CONCLUSION Once-daily use of insulin detemir up to 0.4 U/kg was found to have similar efficacy and safety as twice-daily use. Twice dose use of insulin did not provide a prominent glycemic control advantage on 1.5-fold higher use of insulin.

Investigation of Genotoxicity in Acromegaly From Peripheral Blood Lymphocyte Cultures Using a Micronucleus Assay

CONTEXT Although patients with acromegaly may have an increased risk of developing several types of cancers, the degree of risk for malignancy in these patients is unresolved. OBJECTIVE The present study aimed to investigate the potential genotoxic effects of acromegaly on the cell cycle in peripheral blood lymphocyte cultures. DESIGN This was a single center, crossover, case-control study conducted on the acromegalic patients in Turkey. SETTING The study was conducted in the outpatient clinic of a university hospital. PATIENTS Seventy-one consecutively screened acromegalic patients and 56 controls participated in the study. INTERVENTION Patients were included, regardless of the disease activity status and their treatment duration before the study. MAIN OUTCOME MEASURES The primary end point was the frequency of micronucleus (MN) in the peripheral blood lymphocyte cultures, and the secondary end point was its clinical correlations. RESULTS The MN level was 3.82 ± 1.49 in the control group and 18.00 ± 6.13 in the acromegalic group (P < .01), whereas the nuclear division index (NDI) was 1.79 ± 0.12 in the control group and 1.68 ± 0.07 in the acromegalic group (P < .01). Neither MN nor NDI was correlated with age, GH, IGF-I, initial GH, initial IGF-I, duration of the remission period, and initial tumor size. Only the MN level was positively correlated with the duration of disease (r = 0.323, P = .014). CONCLUSION Our results indicated that acromegalic patients had genotoxic damage at a substantial level, and there was a positive correlation between the duration of disease and genotoxicity level.