Nikolai Fattakhov

Nitric oxide and mitochondria in metabolic syndrome

Metabolic syndrome (MS) is a cluster of metabolic disorders that collectively increase the risk of cardiovascular disease. Nitric oxide (NO) plays a crucial role in the pathogeneses of MS components and is involved in different mitochondrial signaling pathways that control respiration and apoptosis. The present review summarizes the recent information regarding the interrelations of mitochondria and NO in MS. Changes in the activities of different NO synthase isoforms lead to the formation of metabolic disorders and therefore are highlighted here. Reduced endothelial NOS activity and NO bioavailability, as the main factors underlying the endothelial dysfunction that occurs in MS, are discussed in this review in relation to mitochondrial dysfunction. We also focus on potential therapeutic strategies involving NO signaling pathways that can be used to treat patients with metabolic disorders associated with mitochondrial dysfunction. The article may help researchers develop new approaches for the diagnosis, prevention and treatment of MS.

Pathogenesis of insulin resistance in metabolic obesity

This review considers molecular mechanisms of insulin resistance developed under conditions of metabolic inflammation; special attention is paid to analysis of the results of experimental and clinical studies work aimed at identifying molecular targets for the development of new methods for prevention and treatment of insulin resistance.

Pathogenetic significance of single nucleotide polymorphisms in the gastric inhibitory polypeptide receptor gene for the development of carbohydrate metabolism disorders in obesity

Aim. To investigate the association of the GIPR gene polymorphisms rs2302382 and rs8111428 with increased risk of type 2 diabetes mellitus and abdominal obesity. Materials and methods. The study involved 163 patients with abdominal obesity (BMI, 39.5 ± 8.3 kg/m2; age, 44.7 ± 8.9 years; men, 61; women, 102), 72 with type 2 diabetes mellitus (BMI, 43.70 ± 9.32 kg/m2; age, 46.5 ± 10.1 years; men, 29; women, 43) and 91 patients without carbohydrate metabolism disorders (BMI, 36.13 ± 6.72 kg/m2; age, 43.93 ± 8.35 years; men, 32; women 59). The control group comprised 109 relatively healthy volunteers (BMI, 22.6 ± 2.7 kg/m2; age, 39.5 ± 7.6 years; men, 66; women, 43). Genotypes were analysed by real-time PCR and serum insulin and C-peptide levels were evaluated by ELISA. Results. The AA genotype in the rs2302382 polymorphism of GIPR was associated with an increased risk for type 2 diabetes mellitus in abdominal obesity and the CA genotype was associated with a reduced risk. In individuals with abdominal obesity and type 2 diabetes mellitus carrying the CA genotype in rs2302382 polymorphism of GIPR, serum insulin and C-peptide levels were elevated to 56.27 mU/L (55.49–58.41 mU/L) and 2.04 ng/ml (1.37–2.85 ng/ml), respectively (p < 0.05). In obese patients with the same genotype and without type 2 diabetes, serum insulin levels and C-peptide levels were 22.73 mU/L (19.07–25.76 mU/L) and 0.73 ng/ml (0.53–1.03 ng/ml), respectively (p < 0.05). The GIPR rs8111428 polymorphism was not associated with increased risk of type 2 diabetes mellitus in obesity for any of the groups examined. Conclusion. Serum insulin and C-peptide levels were increased in patients with abdominal obesity who were carriers of the CA genotype in the rs2302382 polymorphism of GIPR, which is associated with a decreased risk of type 2 diabetes mellitus in obesity compared with the CC genotype.

The pathogenetic importance of C774T single nucleotide polymorphism of the endothelial nitric oxide synthase gene in the development of metabolic syndrome

The relationship between nitric oxide production and metabolic disorders and the role of endothelial nitric oxide synthase (eNOS or NOS3) in metabolic syndrome (MS) remain poorly understood and need deeper investigation. In this context the role of the NOS3 gene in pathogenesis of MS is of special interest. The aim of the study was to investigate association of NOS3 single nucleotide polymorphism C774T with risk of MS in the Slavic population of the Kaliningrad region and the relationship of this polymorphic variant with some parameters of endothelial dysfunction. The study included 128 patients (48 men and 80 women aged from 36 to 52 years) with MS. The control group consisted of 126 healthy volunteers (60 men and 66 women aged from 30 to 40 years). Genotyping was performed by real-time PCR. Serum nitrite levels were determined spectrophotometrically by the Griess method. Serum levels of endothelin-1 and eNOS were evaluated by ELISA. The study has shown association of T allele (OR = 2.06; p = 0.0004; CI: 1.38–3.08) and CT genotype (OR = 1.97; p = 0.014; CI: 1.14–3.40 ) C774T polymorphism of the NOS3 gene with risk of MS in the Slavic population of the Kaliningrad region. Allele C (OR = 0.48; p = 0.0004; CI: 0.32–0.72) and homozygous CC genotype (OR = 0.41; p = 0.001; CI: 0.24–0.69) C774T polymorphism of the NOS3 gene were associated with reduced risk of the development of MS. Significant differences in serum levels of eNOS and endothelin-1 depended on the CT and TT genotypes of C774T polymorphism of the NOS3 gene in MS.

Haplotype analysis of endothelial nitric oxide synthase (NOS3) genetic variants and metabolic syndrome in healthy subjects and schizophrenia patients

Background/objectivesThe frequency of metabolic syndrome (MetS) is significantly higher in schizophrenia (SCH) patients, when compared to the general populatiotin. The goal of this study was to evaluate whether genetic variants T-786C (rs2070744), G894T (rs1799983) and C774T (rs1549758) in the endothelial nitric oxide (NOS3) gene and/or their haplotypes could be associated with the risk of MetS in SCH patients or healthy subjects from Russian population.Subjects/methodsWe performed two case−control comparisons. NOS3 polymorphisms were genotyped in 70 SCH patients with MetS, 190 normal weight SCH patients, 155 MetS patients, and 100 healthy controls. MetS was defined as per the criteria proposed by the International Diabetes Federation (IDF). Anthropometric, clinical, biochemical parameters, and serum nitrite concentrations were measured in all samples. Haplotype frequency estimations and linkage disequilibrium measures were made using Haploview 4.2.ResultsThe higher C allele (P = 0.009) and lower TT genotype (P = 0.008) frequencies of T-786C polymorphism were found in SCH patients with MetS compared to those in normal weight SCH patients. SCH patients with MetS who were carriers of the T-786C TT genotype had lower serum total cholesterol levels in comparison to the CC genotype (P = 0.016). Furthermore, the 774T/894T haplotype was more frequent in non-SCH individuals with MetS compared to healthy controls (P = 0.0004, odds ratio = 2.18, 95% confidence interval 1.4–3.37). Conversely, the most common haplotype 774C/894G was less frequent in MetS patients than in healthy controls (P = 0.013, odds ratio = 0.61, 95% confidence interval 0.41–0.9).ConclusionsThese results indicate that the NOS3 T-786C promoter polymorphism was closely associated with MetS risk in SCH patients. In addition, the haplotypes composed of G894T and C774T polymorphisms are associated with the MetS susceptibility in Russian population.

Association of Glu298Asp Polymorphism of Endothelial NO Synthase Gene with Metabolic Syndrome Development: a Pilot Study

We studied association of single nucleotide polymorphism Glu298Asp (rs1799983) of the NOS3 gene with the risk of metabolic syndrome in the Slavic population. Blood samples were obtained from 128 patients with metabolic syndrome and 100 healthy individuals. Polymorphism Glu298Asp of the NOS3 gene was genotyped by allele-specific PCR. Allele Asp (OR=1.95, 95%CI 1.29-2.95, p=0.007) and genotype Asp/Asp (OR=2.56, 95%CI 0.98-6.72, p=0.04) were associated with the risk of metabolic syndrome in Slavic population. Patients with metabolic syndrome carrying genotype Asp/Asp had higher serum endothelin-1 level in comparison with Glu/Asp and Glu/Glu carriers.