Halil Genc

Plasma Apelin and ADMA Levels in Patients with Essential Hypertension

Both apelin and asymetric dymethyl arginine (ADMA) regulate blood pressures. Low apelin and high ADMA levels have been reported in several cardiometabolic disorders. However, there is no data about ADMA and apelin levels in essential hypertension and any relationship between them. We investigated a group of newly diagnosed and untreated 30 young hypertensive men and 30 healthy controls. Apelin levels were significantly lower and the ADMA levels were significantly higher in the patients (p = 0.04 for both). Both ADMA and apelin were related to the systolic blood pressures (SBP) (beta = −0.393, p = 0.003; beta = 0.285, p = 0.03, respectively). Future studies are necessary in order to clearly define the role of ADMA and apelin in the pathogenesis of essential hypertension.

Plasma fetuin-A is associated with endothelial dysfunction and subclinical atherosclerosis in subjects with nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD), a hepatic manifestation of metabolic syndrome (MetS) is closely associated with an increased risk of cardiovascular disease. Fetuin‐A is associated with MetS and NAFLD. We investigated the relationship of circulating fetuin‐A level with markers of endothelial dysfunction and presence of carotid atherosclerosis in subjects with NAFLD.

LDL-cholesterol lowering increases plasma apelin in isolated hypercholesterolemia

Apelin, a relatively newer adipokine with various actions in cardiovascular system, was recently reported to decrease in dyslipidemia. The present study addresses whether plasma apelin increases after hypolipidemic intervention either through therapeutic life style change (TLC) or statin treatment. A total of 134 patients were subjected to treatment with a TLC intervention for 12 weeks. Of these, 116 successfully completed the period, and LDL-cholesterol level decreased to target level (<160 mg/dL) in 54 (46.5%) individuals. The remaining 62 patients were treated with rosuvastatin for 12 weeks, and 56 of them finished the study. Circulating apelin, adiponectin, leptin, TNF-alpha, hsCRP and insulin levels were determined both at baseline and after TLC intervention and statin treatment. There was no significant change in plasma apelin concentration in patients unresponsive to TLC (p=0.110). LDL-cholesterol lowering either through TLC or statin treatment was accompanied by an increase in plasma apelin (p=0.000, p=0.020) and adiponectin (p=0.001, p=0.011). Serum leptin decreased after successful TLC (p=0.042/male, p=0.023/female) but not after statin treatment (p=0.959/male, p=0.134/female). Serum TNF-alpha (p=0.902) and plasma hsCRP (p=0.135) levels remained unchanged after TLC intervention but decreased after statin treatment (p=0.000, p=0.023, respectively). Plasma insulin and homeostasis model assessment scores decreased after TLC (p=0.000 for both) but not rosuvastatin treatment (p=0.865, p=0.722, respectively). In conclusion, independent of the type of treatment, reduction in LDL-cholesterol levels in otherwise healthy people with isolated dyslipidemia results in an increase in plasma apelin concentration. More experiments may show a substantial role for this peptide in the mechanism of atherosclerosis.

Mean platelet volume and its relationship with carotid atherosclerosis in subjects with non-alcoholic fatty liver disease.

Abstract Background. Non-alcoholic fatty liver disease (NAFLD) is linked to an increased risk of cardiovascular disease. Mean platelet volume (MPV), a determinant of platelet activation, is an emerging risk factor for atherothrombosis. Aims. The aim of this study was to investigate the levels of MPV in subjects with NAFLD having no confounding factors for atherosclerosis such as obesity, diabetes mellitus, and hypertension. In addition, the possible relationship between MPV and carotid artery intima media thickness (CIMT), a well known marker of subclinical atherosclerosis, was also studied. Methods. MPV and CIMT levels were measured in 60 biopsy-proven NAFLD subjects and 54 healthy controls. Age and sex were similar between two groups. Results. Body mass index and waist circumference levels were higher in the NAFLD group when compared to the controls. There were no differences between the two groups regarding LDL cholesterol levels, whereas HDL cholesterol levels were lower in the NAFLD group. MPV and CIMT levels were not different between the two groups. According to the correlation analyses, CIMT levels were positively correlated to age in patients with NAFLD. However, no significant correlation was found between MPV and CIMT levels. Conclusions. The results of this study do not show any difference in MPV levels between subjects with NAFLD and controls. These finding suggests that in the absence of other metabolic risk factors, MPV might not be involved in the mechanism(s) of increased cardiovascular risk in NAFLD.

The relationship of serum uric acid with non-alcoholic fatty liver disease.

OBJECTIVES Non-alcoholic fatty liver disease (NAFLD) is a clinicopathological entity which is characterized by the presence of fat droplets in hepatocytes without alcohol consumption, representing a spectrum of hepatic injuries, ranging from simple steatosis (SS) to non-alcoholic steatohepatitis (NASH), fibrosis, and cirrhosis. In recent years, experimental and observational studies suggest a role for serum uric acid (SUA) in NAFLD. However, there are few reports investigating SUA in histologically proven NAFLD. The aim of the present study was to evaluate the relationship of SUA with liver histology in non-diabetic patients with NAFLD. DESIGN AND METHODS A total of 242 male patients with NAFLD (102 with NASH and 140 with SS) were included. Histopathological evaluation was carried out according to Kleiners scoring scale. Hyperuricemia was diagnosed as SUA of more than 7 mg/dL. RESULTS The prevalence of hyperuricemia was 33.4%. SUA levels in patients with NASH were significantly higher than those of SS (p=0.035). Univariate and multivariate analyses both demonstrated that hyperuricemia had a significant association with younger age [OR (95%CI), 0.930 (0.884-0.979), p=0.005], higher body mass index [OR (95%CI), 1.173 (1.059-1.301), p=0.002] and hepatocellular ballooning [OR (95%CI), 1.678 (1.041-2.702), p=0.033]. CONCLUSIONS Hyperuricemia is a common finding in patients with NAFLD and is independently associated with early histological findings in this clinically relevant condition. Further longitudinal studies are needed to characterize the role of SUA in the natural history of NAFLD.

Elevated asymmetric dimethylarginine in plasma: An early marker for endothelial dysfunction in non-alcoholic fatty liver disease?

AIMS Non-alcoholic fatty liver disease (NAFLD) is associated with cardiovascular disease. Asymmetric dimethylarginine (ADMA) is a novel marker of endothelial dysfunction and atherosclerosis. We aimed to investigate circulating ADMA concentrations in biopsy proven NAFLD and also to search its association with carotid atherosclerosis. METHODS Sixty-seven nondiabetic and normotensive patients with NAFLD and 35 healthy controls were enrolled. Plasma ADMA was measured along with glucose, lipids and insulin levels. Insulin resistance (IR) was assessed by homeostasis model assessment-estimated insulin resistance (HOMA-IR) method. Carotid atherosclerosis was evaluated by carotid artery intima-media thickness (CIMT) using carotid ultrasonography. RESULTS ADMA levels and CIMT measurements were significantly higher in NAFLD group than the controls. However, the difference regarding the CIMT disappeared when the findings were adjusted according to the metabolic parameters and insulin sensitivity. In contrast, the difference for ADMA remained significant between two groups. No significant association was found between ADMA, CIMT and histopathological findings. CONCLUSIONS Plasma ADMA levels are increased in subjects with NAFLD. This increase seems to be independent from traditional cardiovascular risk factors, insulin resistance and liver histology. Circulating ADMA may be an earlier marker of vascular damage with respect to CIMT in subjects with NAFLD.

Low- and high-density lipoprotein subclasses in subjects with nonalcoholic fatty liver disease.

BACKGROUND Nonalcoholic fatty liver disease (NAFLD) is associated with increased cardiometabolic risk. Although dyslipidemia represents a key factor in this disease, its impact on serum levels of distinct lipoprotein subfractions is largely unknown. OBJECTIVE To assess the full low-density lipoprotein (LDL) and high-density lipoprotein (HDL) profiles in patients with NAFLD. METHODS Seven LDL and 10 HDL subfractions were assessed by gel electrophoresis (Lipoprint, Quantimetrix Corporation, USA) in men with biopsy proven NAFLD (simple steatosis [n = 17, age, 34 ± 7 years] and nonalcoholic steatohepatitis [NASH; n = 24, age, 32 ± 6 years]). Exclusion criteria included robust alcohol consumption, infection with hepatitis B or C virus, body mass index ≥ 40 kg/m(2), diabetes mellitus, and hypertension. RESULTS Compared with simple steatosis, NASH patients had similar body mass index, homeostasis model assessment of insulin resistance index and plasma lipids, with increased levels of both aspartate aminotransferase and alanine transaminase. NASH subjects had lower levels of larger LDL1 (10 ± 4 vs 13 ± 4%, P = .010) and increased smaller LDL3 and LDL4 particles (9 ± 5 vs 5 ± 5%, P = .017 and 3 ± 3 vs 1 ± 2%, P = .012, respectively). No changes were found in the HDL subclass profile. By multiple regression analysis, we found that NASH was associated only with increased levels of LDL3 (P = .0470). CONCLUSIONS The increased levels of small, dense LDL3 and LDL4 in NASH may help to at least partly explain the increased risk for atherosclerosis and cardiovascular diseases in these patients.

Circulating vaspin and its relationship with insulin sensitivity, adiponectin, and liver histology in subjects with non-alcoholic steatohepatitis.

Abstract Objective. Non-alcoholic steatohepatitis (NASH) is closely associated with components of metabolic syndrome. Vaspin is a novel adipocytokine that may link obesity, insulin resistance (IR), and type 2 diabetes mellitus. We aimed to investigate circulating vaspin levels in subjects with NASH and also to search for the association of vaspin with IR, adiponectin, and histological findings. Material and methods. A total of 50 male patients with NASH and 30 healthy male controls were enrolled. Vaspin and adiponectin were measured with ELISA method. Insulin sensitivity determined by homeostasis model assessment (HOMA-IR) index. Results. Plasma vaspin levels were higher and adiponectin levels were lower in NASH group compared with controls (p < 0.01 and p < 0.001, respectively). However, in multivariate analysis adjusted for glucose and lipid parameters, and HOMA-IR indexes, the difference in vaspin concentrations was disappeared. Nonetheless, the difference regarding the adiponectin levels remained significant between groups (p = 0.03). Vaspin was negatively correlated with low-density lipoprotein cholesterol (r = -0.32, p = 0.03) in subjects with NASH. Conclusions. This study indicates that circulating vaspin levels are not altered in male subjects with NASH. These results suggest that in the absence of metabolic risk factors, vaspin per se may not be involved in the pathogenesis of NASH.

The plasma levels of soluble P-selectin in subjects with prediabetes

Prediabetes has been associated with an increased risk of cardiovascular disease and mortality. Soluble P‐selectin (sP‐selectin) is an index of platelet activation and also a risk factor for future vascular events. sP‐selectin levels were investigated in prediabetic subjects who had no confounding factors such as hypertension, obesity or dyslipidaemia. sP‐selectin, hsCRP levels and HOMA‐IR indexes were measured in 40 prediabetic subjects (n = 24 for IFG and n = 16 for IGT) and age‐, sex‐ and BMI‐matched 40 healthy controls. sP‐selectin levels in prediabetic subjects were not significantly different compared with those in controls (p = 0.12). Prediabetic group had similar hsCRP (p = 0.29), higher HOMA‐IR indexes (p < 0.001) and lower HDL cholesterol levels (p = 0.001) when compared with healthy controls. The power of the study was 0.93 for sP‐selectin, 0.7 for hsCRP and 1.0 for HOMA. Our data suggest that sP‐selectin may not contribute to the prothrombotic state as well as the accelerated atherogenesis associated with prediabetes.

Soluble CD40 ligand, soluble P-selectin and von Willebrand factor levels in subjects with prediabetes: the impact of metabolic syndrome.

OBJECTIVES The data regarding circulating levels of markers of platelet activation and endothelial function in people with prediabetes are scant. The aim of the present study was to search blood levels of soluble CD40 ligand (sCD40L), soluble P-selectin (sP-sel) and von Willebrand Factor (vWF) in subjects with prediabetes, along with the effects of the metabolic syndrome (MetS) on these markers. DESIGN AND METHODS A total of 77 prediabetic individuals and 81 age, sex and body mass index matched healthy subjects with normal glucose tolerance (NGT) were prospectively analyzed. Anthropometric parameters, fasting plasma glucose, blood d lipid profiles and insulin resistance indexes were determined. Plasma sCD40L, sP-sel and vWF levels were measured by ELISA. RESULTS sCD40L, sP-sel and vWF levels in the prediabetic group were similar to those in the controls. However, prediabetic subjects with the MetS had significantly higher level of sCD40L compared to those without MetS. Moreover, sCD40L level correlated significantly with waist circumference, systolic blood pressure and HDL-cholesterol level in the patient group. CONCLUSION These data imply that MetS may contribute, at least in part, to the mechanism of platelet activation and endothelial dysfunction in people with prediabetes.