The components of the antioxidant defense (AOD) system were analyzed in 74 male and female adolescents representing small ethnic groups that inhabit the territory of Eastern Siberia. Our findings indicate a dependence of the antioxidant status indicators on gender and ethnic identity of test subjects. More adaptive variants of the AOD system’s functioning were found in Tofalar boys (elevated levels of fat-soluble vitamins, increased glutathione system activity), whereas Evenk boys were characterized by a decreased activity of antioxidant factors (low α-tocopherol and retinol supply, glutathione system imbalance), as compared both to girls and Tofalar boys. The changes revealed in this group were also supported by increased values of the oxidative stress index.

Background. The hormonal alteration in menopause can lead to changes in the lipid metabolism parameters. The results of studies on this issue are ambiguous and suggest ethno-specific changes in the lipid profile. Aim: comparative assessment of lipid metabolism parameters in women of Caucasian and Asian races in peri- and postmenopause. Materials and methods. 146 women of Caucasian (ethnic group - Russian (n = 82)) and Asian (ethnic group - Buryats (n = 64)) races participated as volunteers in the prospective non-randomized study for the period 2012-2016. Each ethnic group was divided into three subgroups - women of reproductive age, women in perimenopause, and in postmenopause, according to the gynecological status. The lipid metabolism parameters were determined by the enzymatic method on a biochemical analyzer BTS-330. When analyzing the intergroup differences for independent samples, nonparametric criteria were used. Results. In Russian perimenopausal women, compared with women of reproductive age, we registered an increase in triglycerol levels by 1.90 times (p < 0.05) and cholesterol of very low density lipoproteins by 2.10 times (p < 0.05), followed by an increase of total cholesterol levels by 1.22 times (p < 0.05) and low-density lipoprotein cholesterol by 1.40 times (p < 0.05) in postmenopausal period. In representatives of the Buryat ethnos, the changes in the lipid metabolism parameters were detected only in postmenopause, they consisted in increased total cholesterol levels - by 1.31 times (p < 0.05) and low density lipoprotein cholesterol - by 1.45 times (p < 0.05). Conclusions. Changes in the lipid profile in menopause are more pronounced in representatives of the Russian ethnic group.

It is assumed that in the progression of obesity, complicated by fatty hepatosis in adolescents, a significant role is given to the reactions of oxidative stress with deficiency of antioxidant factors. However, an important factor that remains outside the field of view of researchers is the ethnicity of the patient, which is an important element in the development of a personalized approach in the treatment and prevention of diseases. In connection with this, the purpose of this study was to study the changes in the lipid peroxidation-antioxidant defense processes in adolescent Mongoloids with exogenously constitutional obesity complicated by fatty hepatosis. 18 adolescent boys with fatty hepatosis were examined on the background of exogenous-constitutional obesity of the first degree; 38 adolescent boys with exogenously constitutional obesity without changes in the liver and 37 practically healthy adolescents (control group). All subjects surveyed for ethnicity belonged to the Mongoloids. Spectrophotometric and fluorometric methods were used in the research. The results of the study indicated a high intensity of lipid peroxidation reactions in Mongoloid boys with obesity and fatty hepatosis relative to control values: an increase in blood plasma content of compounds with unsaturated double bonds (p<0.001), diene conjugates (p=0.0012), ketodienes and conjugated trienes (p<0.0001), in the absence of significant differences in the level of TBA-active products. Increased values of total antioxidant activity in blood plasma (p=0.0023) and erythrocyte superoxide dismutase activity (p=0.0072), decreased levels of fat-soluble vitamins in blood plasma [α-tocopherol (p<0.0001) and retinol (p=0.0011)] and oxidized form of glutathione in erythrocytes (p=0.0083) have been found. The pronounced insufficiency of fatsoluble vitamins - α-tocopherol and retinol in patients of the main group was also noted in comparison with patients without morphological changes in the liver. Thus, in teenage Mongoloids with exogenously constitutional obesity and fatty hepatosis, it is possible to recommend antioxidant drugs in addition to basic metabolic therapy.

The indicators of lipid metabolism were analyzed comparatively in 258 adolescent girls and boys representing major ethnic groups of Eastern Siberia: indigenous Tofalars, Evenks and Buryats and alien Europoids (Caucasoids). The adolescent lipid profile in these groups was found to be ethnos-specific. In contemporary Tofalars and Buryats, its indicators are stable, while the overall lipid profile shows an anti-atherogenic trend. By contrast, Evenks and Europoids show an increasing level of cholesterol-containing blood components.

The problem of obesity is extremely relevant for modern medical science and healthcare, and child and adolescent obesity deserves special attention. It seems to be interesting to trace the interrelation of pathological processes in obesity in the form of metabolic disorders at the level of the organism and at the cell level - disorders in the system of lipid peroxidation. Studies in adolescent boys are relevant, as there has been a general increase in the incidence in this age category. The purpose of the research was to study the state of the system “lipid peroxidation – antioxidant protection” in adolescent boys with exogenous-constitutional obesity. 19 adolescent boys with obesity were examined in comparison with the control group. Spectrophotometric and fluorometric methods of examination were used. An increase in the level of secondary lipid peroxidation products – ketodienes and conjugated trienes (1.65 times) – was revealed in adolescent boys with obesity. In the antioxidant defense system, differences in this group included reduced values of α-tocopherol (1.42 times), retinol (1.51 times) and superoxide dismutase activity (1.19 times), in the absence of statistically significant changes in the total antioxidant activity (AOA) in blood and components of glutathione status. The revealed disorders allow to recommend the complex therapy including prescription of antioxidants and medicines directed on normalization of lipid exchange at the given category of patients.

One of the most topical problems in the field of healthcare is to solve the issues of an early diagnosis, timely prevention and effective treatment of cardiovascular diseases, which include arterial hypertension (the AH]. Prevalence of EAH in the pediatric population in Russia amounts to 20 %. Despite the fact that the mechanisms of the disease were studied in detail, metabolic changes that led to its early deve^ment in teenagers were still not entirely clear. In the Clinic of FSBSI Scientific Center for Family Health Problems and Human Reproduction (Irkutsk], clinical and functional examination of 48 male adolescents aged 14-17 years, of which 25 patients with stable arterial hypertension and 23 adolescents without somatic pathology with normal blood pressure, was conducted. Antioxidant status was studied in blood plasma and hemolysate. A comparative analysis of the following indicators was conducted: total antioxidant activity, superoxide dismutase activity, level of retinol and α-tocopherol, glutathione system parameters. Patients with stable arterial hypertension were recorded with level of overall antioxidant activity in blood 29 % higher than the benchmark, decreased superoxide dismutase activity by 11 % and content of а-tocopherol by 44 %. Retinol concentration in teenagers with hypertension was two times higher than the content of this indicator in the control group (р = 0.00]. Decrease in the antioxidant levels was found in adolescents with arterial hypertension that can be the cause of the oxidative stress development.

The article presents literature data on the lipid peroxidation and antioxidant defense system (LPO-AOD) under normal conditions. Lipid peroxidation is a physiological process which is constantly occurring in cell membranes and has a chain, free-radical mechanism. Free-radical reactions are involved in the repair of cell membranes, in the processes of phagocytosis and destruction of microorganisms, in conducting nerve impulses, in metabolism of various xenobiotics by liver and in biosynthesis of certain biologically active substances such as prostaglandins. Antioxidant defense neutralizes all kinds of radicals before they cause damage effect in a body. The imbalance in the LPO-AOD system causes oxidative stress. Nowadays research of this process in children of different age is very topical. Thus, reduction of the AOD intensity was proved in case of diseases such as arterial hypertension, chronic gastroduodenitis, influenza, cholelithiasis, pyelonephritis, metabolic syndrome, diabetes mellitus type 1. The conclusion on the necessity of inclusion of drugs with antioxidant action in the complex therapy of various pathological conditions along with the medical methods of treatment is made. Thus, the efficiency of the treatment of various diseases largely depends on the protection of the structure and function of cell membranes, and as a result the inclusion of drugs with antioxidant action in the treatment of almost any pathology in childhood is justified.

The aim of this research was to investigate the glutathione system components and their association with polymorphisms GST genes in men with infertility. Materials and Methods: One hundred and sixty Russian men of reproductive age (Caucasians) who came to the public health institution Republican Perinatal Center in Ulan-Ude with an infertility problem of one year and more after marriage were included in the main group. The control group included 104 men with proven fertility. DNA samples were genotyped for polymorphisms in GSTP1, GSTT1 and GSTM1genes and activity of glutathione system enzymes was determined. Results: The most informative genetic and metabolic indicators in Caucasian males with infertility were combinations of the null genotypes GSTT1(*0/*0)+GSTM1(*0/*0) associated with a decrease of GST activity in blood and ejaculate and an increase of GSH and GPO in the blood. Another combination is GSTP1(Ile105Val)+GSTP1(Ala114Val), which is associated with suppression of the blood and ejaculate GPO activity and a decrease in blood concentration of GSH.

The article presents the results of the research of some indices of lipid peroxidation and antioxidant defense in children of 11–13 years with essential arterial hypertension that were obtained by the methods of spectrophotometry and chemiluminescence. Quantity of products of lipid peroxidation – antioxidant defense in blood serum of patients with essential arterial hypertension significantly exceeds this index in control group. Intensity of the lipid peroxidation processes expressed by the indices of chemiluminescence was higher in patients with essential arterial hypertension than in control group.