Ozen Oz Gul

Decreased plasma levels of soluble receptor for advanced glycation endproducts (sRAGE) in patients with nonalcoholic fatty liver disease

OBJECTIVES Levels of soluble receptor for advanced glycation endproducts (sRAGE) have been linked to several components of the metabolic syndrome. We tested the hypothesis that plasma levels of sRAGE may be associated with non-alcoholic fatty liver disease. DESIGN AND METHODS We enrolled subjects with definite nonalcoholic steatohepatitis (NASH, n=40), borderline NASH (n=8), simple fatty liver (n=9) and healthy controls (n=14). Plasma levels of sRAGE were measured by ELISA. RESULTS Concentrations of sRAGE were significantly lower in patients with definite NASH (1080+/-392 pg/mL, P<0.01) and borderline NASH (1050+/-278 pg/mL, P<0.05) compared to controls (1480+/-387 pg/mL). Levels of sRAGE were significantly and inversely correlated with ALT (r=-0.30, P<0.05) and AST (r=-0.23, P<0.05). CONCLUSION Plasma levels of sRAGE are significantly reduced in definite and borderline NASH.

Evaluation of chromosome aberrations, sister chromatid exchange and micronuclei in patients with type-1 diabetes mellitus

Oxidative stress-induced DNA damage seems to play a role in the pathogenesis of type-1 diabetes mellitus and its complications. Several in vitro assays have been used to measure the DNA damage produced by oxidative stress. In the present study, we aimed to investigate the frequency of sister chromatid exchange (SCE), chromosomal aberrations (CA) and micronuclei (MN) in type-1 diabetes mellitus patients compared with healthy controls. SCE, CA and MN tests were carried out with the blood-cell cultures from 35 type-1 diabetic patients and 15 healthy, age- and sex-matched control subjects. The mean age of the type-1 diabetic patients was 31.89 +/- 10.01 years, with a mean duration of the diabetes of 7.8 +/- 6.02 years. The mean level of HbA1c of the type-1 diabetic patients was 8.37+/-1.36%. Only three (8.5%) patients with type-1 diabetes mellitus had an HbA1c level below 7%. Patients with type-1 diabetes mellitus showed a higher frequency of SCE compared with controls (5.44 +/- 1.47 and 2.54 +/- 0.82, respectively, p < 0.001), but there was no significant correlation between the duration of diabetes, HbA1c and SCE. No significant difference was found in CA or MN frequency in type-1 diabetic patients compared with controls. In conclusion, these results suggest that type-1 diabetes mellitus is a condition with genomic instability characterized by an increased level of SCE. Hyperglycemia-induced oxidative stress may be the underlying factor of the increased SCE frequency.

Effect of rosiglitazone, metformin and medical nutrition treatment on arterial stiffness, serum MMP-9 and MCP-1 levels in drug naive type 2 diabetic patients.

The aim of the study was to evaluate the long-term effect of rosiglitazone and metformin monotherapy with medical nutrition treatment (MNT) and of MNT alone on arterial stiffness, serum monocyte chemoattractant protein (MCP)-1 and matrix metalloproteinase (MMP)-9 in drug naive patients with type 2 diabetes mellitus. Fifty type 2 diabetic patients were randomized to receive rosiglitazone 4 mg/day (n=19) or metformin 850 mg/day (n=16) with MNT or MNT alone (n=15), for 52 weeks. Arterial stiffness was assessed by using large and small artery elasticity index (SAEI and LAEI, respectively). SAEI, LAEI, serum MCP-1 and MMP-9 levels were measured at baseline and following 52 weeks of treatment. SAEI was improved only in the rosiglitazone group, and the difference was still statistically significant when the three groups were compared (p=0.024). There were no differences in LAEI in inter- and intragroup comparisons at the end of the study. Serum MMP-9 levels were decreased in the metformin (-13.5+/-34.8%, p=0.02) and rosiglitazone (-27.2+/-51.0%, p=0.023) groups compared with baseline values, whereas no significant change was seen in serum MCP-1 levels. These results suggest that rosiglitazone monotherapy has favorable effects on arterial stiffness compared with metformin monotherapy independent of glycemic control.

Comparative effects of pioglitazone and rosiglitazone on plasma levels of soluble receptor for advanced glycation end products in type 2 diabetes mellitus patients

Low levels of soluble receptor for advanced glycation end products (sRAGE) have been associated with the occurrence of vascular complications in patients with type 2 diabetes mellitus. Preliminary evidence has suggested that thiazolidinediones have the ability to modulate circulating levels of this molecule in the hyperglycemic milieu. The aim of this pilot study was to assess the differential effect of 2 different thiazolidinediones-pioglitazone and rosiglitazone-on plasma levels of sRAGE in type 2 diabetes mellitus patients. Sixty type 2 diabetes mellitus subjects were randomly assigned to receive pioglitazone (30 mg/d, n = 19), rosiglitazone (4 mg/d, n = 20), or placebo (medical nutrition therapy, n = 21) for 12 weeks. Changes in plasma glucose, glycosylated hemoglobin, insulin resistance (homeostasis model assessment), total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglycerides, and sRAGE were evaluated at baseline and after 12 weeks. At 12 weeks, the pioglitazone (P < .001) group had a significant increase from baseline in sRAGE values that was not seen in the medical nutrition therapy and rosiglitazone groups. We conclude that, in type 2 diabetes mellitus patients, pioglitazone-but not rosiglitazone-significantly raised sRAGE, which may contribute to its antiatherogenic effects.

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.

Comparative genotoxic and cytotoxic effects of the oral antidiabetic drugs sitagliptin, rosiglitazone, and pioglitazone in patients with type-2 diabetes: A cross-sectional, observational pilot study

This cross-sectional, observational pilot study was designed to investigate the frequency of different endpoints of genotoxicity (sister-chromatid exchange, total chromosome aberrations, and micronucleus formation) and cytotoxicity (mitotic index, replication index, and nuclear division index) in the peripheral lymphocytes of patients with type-2 diabetes treated with different oral anti-diabetic agents for 6 months. A total of 104 patients who met the American Diabetes Association criteria for type-2 diabetes were enrolled in the study. Of the 104 patients, 33 were being treated with sitagliptin (100mg/day), 25 with pioglitazone (30mg/day), 22 with rosiglitazone (4mg/day), and 24 with medical nutrition therapy (control group). The results for all the genotoxicity endpoints were significantly different across the four study groups. Post hoc analysis revealed that the genotoxicity observed in the sitagliptin group was significantly higher than that observed in the medical nutrition therapy group, but lower than that occurring in subjects who received thiazolidinediones. All of the three cytotoxicity endpoints were significantly lower in patients treated by oral anti-diabetic agents compared with those who received medical nutrition therapy. However, the three indexes did not differ significantly in the sitagliptin, rosiglitazone, and pioglitazone groups. Taken together, these pilot data indicate that sitagliptin and thiazolidinediones may exert genotoxic and cytotoxic effects in patients with type-2 diabetes. Further investigations are necessary to clarify the possible long-term differences between oral anti-diabetic drugs in terms of genotoxicity and cytotoxicity, and how these can modulate the risk of developing diabetic complications in general and cancer in particular.

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.

A nation-wide survey of patients with homozygous familial hypercholesterolemia phenotype undergoing LDL-apheresis in Turkey (A-HIT 1 registry)

BACKGROUND AND AIMS Homozygous familial hypercholesterolemia (HoFH) is a genetic condition characterized by lethally high levels of low-density lipoprotein cholesterol (LDL-C) from birth, and requires rapid and aggressive intervention to prevent death due to coronary heart disease and/or atherosclerosis. Where available, lipoprotein apheresis (LA) is the mainstay of treatment to promote survival. METHODS A-HIT1 registry was conducted with the aim of providing insight to the real-life management of HoFH patients undergoing LA in Turkey, where LA procedures are fully reimbursed and widely available. Participating centers provided patient information, including family history, treatment patterns and relevant laboratory values, via a standard questionnaire. RESULTS The study evaluated 88 patients (mean age: 27 ± 11 years, 41 women) in 19 centers. All patients were receiving regular LA with a clinical diagnosis of HoFH. Mean age at first symptom disease was 10 ± 10 years, and at diagnosis it was 12 ± 11 years; 74.7% were diagnosed before age 15 years; and only 31% before the age of 7. First referral of most patients was to pediatricians. Early onset coronary artery disease was present in 57.8% of patients. Mean age at first LA was 21 ± 12 years. Only 11 (12.5%) patients were undergoing LA weekly. Mean frequency of apheresis sessions was 19 ± 13 days. For the last four LA sessions, LDL-C levels reached the target in only in 5.7% of patients. CONCLUSIONS Diagnosis of HoFH is delayed, and LDL targets are not reached. LA frequencies are not optimal. Urgent attention is needed to support the survival of patients with HoFH.

Evaluation of insulin resistance and plasma levels for visfatin and resistin in obese and non-obese patients with polycystic ovary syndrome

This study was designed to evaluate insulin resistance and plasma levels of visfatin and resistin in obese and non-obese patients with polycystic ovary syndrome (PCOS).A total of 37 premenopausal PCOS patients with (n = 18, mean (SD) age: 27.5 (5.7 years) or without obesity (n = 19, mean (SD) age: 23.7 (3.1) years) and healthy volunteers (n = 18, mean (SD) age:29.8 (4.1) years) were included in this study. Data on clinical characteristics, glycemic parameters and lipid parameters were recorded for each subject as were plasma visfatin and resistin levels. Mean (SD) HOMA-IR values were significantly higher in obese PCOS patients (3.4 (1.7)) compared with non-obese PCOS patients (2.0 (1.2), p<0.01) and controls (1.6 (0.8), p<0.01). No significant difference was noted between study groups in terms of plasma resistin (ng/mL) or visfatin (ng/mL) levels. There was no correlation between serum plasma visfatin (r = 0.127, p = 0.407) and resistin (r = -0.096, p = 0.544) levels and HOMA-IR. In conclusion, our findings revealed increased likelihood of metabolic and dyslipidemic manifestations in obese compared to non-obese PCOS patients, while no significant difference was noted in visfatin and resistin levels among PCOS patients in terms of co-morbid obesity and in comparison to controls.