Ayhan Karakoc

Circulating concentrations of adiponectin and tumor necrosis factor-α in gestational diabetes mellitus

Adiponectin and tumor necrosis factor-α (TNF-α) have been implicated in insulin resistance and diabetes mellitus (DM). In the present study we investigated levels of adiponectin and TNF-α and their relationships with each other and metabolic factors in women with gestational DM (GDM). Thirty-four pregnant women with GDM and 31 pregnant women with normal glucose tolerance (NGT) were included in the study. Plasma adiponectin levels were lower in GDM than in NGT (36.9 ± 6.7 vs. 61.3 ± 13.0 ng/ml, p = 0.028). Serum TNF-α levels were increased in GDM compared with NGT (20.5 ± 2.4 vs. 14.0 ± 1.5 pg/ml, p = 0.042). After adjustment for pre-pregnancy and current body mass index (BMI), adiponectin levels correlated negatively with insulin resistance by homeostasis model assessment-insulin resistance (HOMA-IR) and 0-h and 1-h glucose both at glucose challenge test and oral glucose tolerance test in GDM. Adiponectin levels were correlated only with very low-density lipoprotein cholesterol and triglyceride levels in NGT. TNF-α levels were correlated with glycated hemoglobin in GDM. There was a significant positive correlation between TNF-α levels and pre-pregnancy and current BMI in GDM as well as NGT. HOMA-IR for adiponectin and pre-pregnancy BMI for TNF-α remained as significant determinants in multiple regression analyses. In conclusion, these data suggest that reduced adiponectin and increased TNF-α may be involved in the pathogenesis of GDM.

The effects of rosiglitazone and metformin on insulin resistance and serum androgen levels in obese and lean patients with polycystic ovary syndrome

Aim: The aim of this study was to assess the effects of metformin and rosiglitazone on insulin resistance and serum androgen levelsin both obese and lean patients with polycystic ovary syndrome (PCOS). Materials and methods: Forty lean [body mass index (BMI) <25 kg/m2] and 40 overweight and obese (BMI>²5 kg/m2) patients were included in the study. Waist and hip measurements, serum sex steroid levels, insulin response to 75-g oral glucose tolerance test, fasting insulin, fasting C-peptide levels and homeostasis modelassessment of insulin resistance (HOMA-IR) were determined in all patients. The degree of hirsutism was determined by the Ferriman-Gallwey scoring system. Patients were divided into two groups, with 40 (20 overweight and obese; 20 non-obese) patients each. One group was treated with metformin (MET group) 850 mg bid while the other received rosiglitazone (ROSI group) 4 mg/day for 12 weeks. All measurements were repeated at the end of this period. Results: After the 12-week treatment period, HOMA-IR, area under the curve of insulin, fasting insulin and C-peptide levels were observed to have be decreased significantly in all groups. The decrease in the parameters mentioned above was similar in the four groups. The serum levels of free testosterone, androstenedione and DHEA-S decreased in all groups, but the decrease was statistically significant only in the ROSI groups. Within the lean MET group one patient became pregnant and was hence excluded from the final data analysis. Menstruations became regular after metformin therapy in 41.6% of lean and 35.7% of obese patients who had menstrual disturbance prior to the study. Rosiglitazone therapy improved menstrual disturbance in 61.5 % of lean and 53.8% of obese patients. Conclusions: Our data showed that both metformin and rosiglitazone increased insulin sensitivity in obese patients with PCOS as expected, and in lean patients as well. Rosiglitazone seemed to be more effective in decreasing the androgen levels and in achieving slightly greater improvement in menstrual disturbance than metformin.

The effects of rosiglitazone and metformin on menstrual cyclicity and hirsutism in polycystic ovary syndrome.

Objective. The aim of the present study was to assess the effects of metformin and rosiglitazone on menstrual cyclicity and hirsutism in patients with polycystic ovary syndrome (PCOS). Materials and methods. Ninety-six patients were included in the study. Serum sex steroids, serum fasting glucose and insulin levels, and insulin response to a 75-g oral glucose tolerance test were assessed in all patients. Menstrual cyclicity, with recording of menses in the 6-month periods before the study and during treatment, was evaluated in each patient. Patients were divided into two groups: one was treated with metformin (MET group, n = 48), while the other received rosiglitazone (ROSI group, n = 48). At baseline and after 24 weeks of treatment all patients underwent hormonal and clinical assessments, including body mass index (BMI), waist and hip measurements and Ferriman – Gallwey (FG) scores. Results. Of the 96 patients included in the study, 88 (91.7%) were able to complete it and yielded data for analyses. After the 24-week treatment period, fasting insulin levels and area under the curve for serum insulin decreased significantly, while the glucose/insulin ratio increased in both groups. The degree of reduction in serum free testosterone and androstenedione levels was similar in the two groups. The decreases in luteinizing hormone/follicle-stimulating hormone ratio and serum dehydroepiandrosterone sulfate levels were significantly greater in the ROSI group compared with the MET group. BMI increased in the ROSI group, while it decreased in the MET group. In patients with menstrual disturbance treated with rosiglitazone, menstrual cycles became regular in 87.8%, while improvement occurred in 79.3% of the patients treated with metformin. FG score decreased in both ROSI and MET groups, but the degree of decrease was significantly greater in the ROSI group than in the MET group. Conclusion. Our data show that both metformin and rosiglitazone improve ovarian function and hirsutism in patients with PCOS. Rosiglitazone appears better than metformin in the treatment of hirsutism and has better patient tolerance.

Levels of lipoprotein and homocysteine in non-obese and obese patients with polycystic ovary syndrome

Aim. This study was designed to examine the relationship between homocysteine (Hcy), lipoprotein levels and insulin resistance in obese and non-obese patients with polycystic ovary syndrome (PCOS). Materials and methods. Eighty-five patients (38 obese, 47 non-obese) with PCOS and 50 healthy subjects (25 obese, 25 non-obese) were included in the study. PCOS was defined according to the Homburg criterion. Serum levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), dehydroepiandrosterone sulfate (DHEA-S), insulin, 17-hydroxyprogesterone, free testosterone, androstenedione, vitamin B12 and folate were measured. Also, serum concentrations of total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglycerides (TG), lipoprotein (a) (Lp(a)), apoprotein B (Apo B) and apoprotein A (Apo A) were determined. Plasma Hcy levels were measured. Insulin resistance was evaluated by homeostasis model assessment (HOMA). Results. Plasma Hcy levels were significantly higher in women with PCOS than in healthy women. HOMA-R (insulin resistance) was significantly higher in women with PCOS compared with healthy women. Serum fasting TC, LDL-C, TG, Apo B, vitamin B12 and folate levels were similar between PCOS and control groups. Lp(a) levels were higher in PCOS patients than in control subjects, whereas HDL-C and Apo A levels were lower. Compared with obese PCOS subjects, non-obese PCOS subjects had low HOMA-R, TC, LDL-C, TG, Apo B, Lp(a) and androgen levels. Plasma Hcy levels, serum HDL-C and Apo A levels were similar between obese and non-obese women with PCOS. Levels of HDL-C and Apo A were lower in both obese and non-obese PCOS patients than in obese and non-obese control subjects, whereas Lp(a) levels were higher. No correlation was observed between plasma Hcy, body mass index, HOMA-R, serum androgen levels, TC, LDL-C, HDL-C, Apo A, Apo B and Lp(a) levels. Conclusion. These results showed that elevated insulin resistance and plasma Hcy levels, and changes in serum lipid profile, which are possible risk factors for cardiovascular disorders, play important roles in the development of cardiovascular disease in both obese and non-obese patients with PCOS.

Risk factors for cardiovascular disease in patients with subclinical hypothyroidism

IntroductionThe relationship between subclinical hypothyroidism (SCH) and cardiovascular disease is not fully understood. We investigated risk factors for cardiovascular disease (lipid profile, lipoproteins, insulin resistance, C-reactive protein [CRP] homocysteine [Hcy] and fibrinogen levels) and their relationships with thyroid hormones in SCH patients and controls.MethodsThirty-eight SCH patients and 44 controls were enrolled in this study. No patients had any substantial confounding medical conditions (including diabetes mellitus or coronary heart disease) or were taking thyroidrelated medication.ResultsSerum total cholesterol (P<0.05), low-density lipoprotein cholesterol (P<0.05) and triglycerides (P<0.001) were higher in patients with SCH than in controls. Serum lipoprotein(a) (Lp[a]) levels were higher in SCH subjects but this difference did not reach statistical significance (P=0.07). No significant differences were noted in CRP, Hcy, fibrinogen, high-density lipoprotein cholesterol, apolipoprotein A-1, apolipoprotein B (Apo B) or insulin resistance between patients with SCH and controls (in all cases, P>0.05). Free triiodothyronine (FT3) negatively correlated with Apo B (r=.0.46, P=0.005) and Lp(a) (r=.0.31, P=0.03) in patients with SCH and negatively correlated with Lp(a) (r=.0.30, P=0.04) in controls. All of these parameters were comparable between patients with thyroid-stimulating hormone (TSH) >10 μIU/ml and TSH <10 μIU/ml (in SCH patients, P>0.05).ConclusionOur results suggest that SCH is associated with some lipid and lipoprotein abnormalities. Our results also suggest that this association does not depend on the subject’s TSH level.

Pro12Ala polymorphism of the peroxisome proliferator-activated receptor-γ gene in women with polycystic ovary syndrome

Aim. The present study was designed to examine the relationship between Pro12Ala polymorphism of the peroxisome proliferator-activated receptor-γ gene (PPAR-γ) and clinical and hormonal characteristics in women with polycystic ovary syndrome (PCOS). Materials and methods. One hundred patients with PCOS and 100 healthy subjects were included in the study. Serum levels of sex steroids were measured. Insulin resistance was evaluated by homeostasis model assessment (HOMA). The responses of glucose and insulin to an oral glucose tolerance test were analyzed by calculating the respective area under the curve (AUC) by the trapezoidal method. We used the restriction fragment length polymorphism technique and polymerase chain reaction to examine Pro12Ala polymorphism in exon 2 of PPAR-γ. Results. Pro12Ala polymorphism of PPAR-γ was significantly elevated in control subjects (22%) compared with PCOS subjects (15%). All of the Pro12Ala polymorphisms of PPAR-γ were heterozygous. When PCOS subjects with the Pro allele and the Ala allele of PPAR-γ were compared, the latter had lower free testosterone, androstenedione, dehydroepiandrosterone sulfate, insulin and C-peptide levels, as well as lower luteinizing hormone/follicle-stimulating hormone ratio, HOMA insulin resistance index, AUCinsulin, Ferriman–Gallwey score, acne, body mass index and waist-to-hip ratio. Conclusion. We suggest that Pro12Ala polymorphism of the PPAR-γ gene may be a modifier of insulin resistance in women with PCOS.

Pro12Ala polymorphism of the peroxisome proliferator-activated receptor-gamma gene in first-degree relatives of subjects with polycystic ovary syndrome.

Aim. This study was designed to examine the relationship between the Pro12Ala polymorphism of the peroxisome proliferator-activated receptor-γ (PPAR-γ) gene and insulin resistance (IR) in first-degree relatives of subjects with polycystic ovary syndrome (PCOS). Materials and methods. One hundred and twenty family members of 55 patients with PCOS and 80 unrelated healthy control subjects without a family history of diabetes or PCOS were studied. IR was assessed by homeostatic model assessment (HOMA-IR) and area under the curve (AUC) for insulin during an oral glucose tolerance test in subjects with normal glucose tolerance and controls. Genetic analysis of the PPAR-γ gene Pro12Ala polymorphism was performed by restriction fragment length polymorphism. Results. Fasting insulin, HOMA-IR and AUC insulin were significantly higher in first-degree relatives of PCOS subjects than in controls. A significantly different allele distribution of the Pro12Ala polymorphism of PPAR-γ was observed between the two groups, with the frequency of the variant Ala isoform being significantly reduced in the first-degree relatives of PCOS subjects (10.8%, 13 subjects) compared with the control group (22.5%, 18 subjects). All Pro12Ala polymorphisms of the PPAR-γ gene were heterozygous. Compared with first-degree relatives of PCOS subjects with the Pro12Pro polymorphism of PPAR-γ, first-degree relatives of PCOS subjects with the Pro12Ala polymorphism had low fasting insulin, HOMA-IR and AUC insulin levels. The combined prevalence rate for impaired glucose tolerance, impaired fasting glucose and diabetes was 40% (16 subjects) in mothers and 52% (20 subjects) in fathers of PCOS women. Conclusion. Our findings suggest that Pro12Ala PPAR-γ gene polymorphism may be protective against IR and might prevent the development of diabetes mellitus in the first-degree relatives of subjects with PCOS.

Calpain 10 gene single-nucleotide 44 polymorphism may have an influence on clinical and metabolic features in patients with polycystic ovary syndrome

Aim: This study was designed in order to examine the relationship between Calpain 10 [single-nucleotide polymorphism (SNP) 19,43,44,63] gene polymorphisms and clinical and hormonal characteristics in women with polycystic ovary syndrome (PCOS). Materials and methods: One hundred and seven patients with PCOS and 114 healthy subjects were included in this study. Serum levels of sex steroids were measured for each individual. Insulin resistance (IR) was evaluated by the homeostasis model assessment (HOMA) and quantitative insulin-sensitivity check index (QUICKI) methods. Insulin and glucose responses to the oral glucose tolerance test (OGTT) were analyzed by calculating the areas under the curve for insulin (AUCI) and glucose by the trapezoidal methods. We used PCR and restriction fragment length polymorphism technique to examine Calpain 10 SNP 19, 43, 44, and 63 polymorphisms. Results: Allele distribution of Calpain 10 SNP 44 gene polymorphism was observed as significantly different between the groups. Calpain 10 SNP 44 TC genotype was found to be increased in PCOS subjects (69.15%) compared to the control subjects (50%). However, when compared to control subjects, patients with PCOS had similar Calpain 10 SNP 19, Calpain 10 SNP 43, and SNP 63 gene polymorphisms. When compared with normal Calpain 10 gene SNP 44 allele in PCOS subjects, subjects with PCOS having Calpain 10 gene SNP 44 allele polymorphism had higher free testosterone, androstenedione, DHEA-S, and fasting insulin levels. Also, PCOS women with Calpain 10 gene SNP 44 allele polymorphism had high Ferriman-Gallwey (F-G) score, acne, prevalence of menstrual disturbances, waist-hip ratio, HOMA-IR, AUCI levels and low QUICKI levels. Conclusion: The findings show that Calpain 10 gene SNP 44 allele polymorphism may have a role in PCOS pathogenesis. However, larger-scale studies are needed in this field.

The Effects of Hypothyroidism in Rats on Serum Leptin Concentrations and Leptin mRNA Levels in Adipose Tissue and Relationship with Body Fat Composition

Both thyroid hormones and leptin affect sympathetic nervous system activity, basal metabolic rate, body fat mass, food intake, and thermogenesis, and each one also affects the actions of the other. We examined the alterations in serum leptin concentrations and leptin mRNA expression in hypothyroid rats and investigated the relation between serum leptin and leptin mRNA levels with the total adipose tissue mass and total body weight. Twenty male Wistar rats were divided into 2 groups, euthyroid and hypothyroid. Their body compositions were examined by Dual Energy X‐ray Absorptiometry at the beginning and end of the study. Serum leptin concentrations and levels of leptin mRNA in the retroperitoneal white adipose tissue were measured at the end of the study. Serum leptin concentrations did not show any difference between the two groups (1.9 ± 0.2 ng/ml in the hypo and euthyroid group, P > 0.05), but the fat mass of the hypothyroid rats were lower than the euthyroid rats (21.1 ± 2.5 g in the euthyroid group and 14.2 ± 1.9 g in the hypothyroid group, P > 0.05 between groups at the end of the study) although the difference between the groups was statistically not significant. Leptin mRNA level was significantly higher in the hypothyroid group than in the euthyroid group (21.6 ± 1.6 vs. 15.1 ± 1.2 ng respectively, P = 0.002) although the dissected retroperitoneal fat weight was significantly lower in the hypothyroid group versus the euthyroid group (1.0 ± 0.2 vs. 1.8 ± 0.2 g respectively, P = 0.013). In conclusion, the change of leptin mRNA expression in white adipocytes was thought to be the direct result of hypothyroidism or a compensatory response to metabolic changes caused by hypothyroidism.

Thyroid fine needle aspiration biopsy: is topical local anaesthesia beneficial?

Objective:  Thyroid fine needle aspiration biopsy (TFNAB) is the gold standard in the differential diagnosis of the thyroid nodules. In general, no analgesia is needed before this procedure. However, it is usually believed that the patients may be more comfortable if the procedure is performed under local anaesthetics. In this study, we examined the impact of the use of dermal anaesthetic on the patient’s level of discomfort during palpation‐guided TFNAB.