S. I. Kolesnikov

Hepatocyte Apoptosis in Rats Exposed to Benzo(a)pyrene

We studied the effect of benzo(a)pyrene on activity of nuclear endonucleases and expression of molecular regulator of apoptosis Bcl-2 in liver cells in rats. Intraperitoneal injection of benzo(a)pyrene (in a total dose of 60 mg/kg body weight) reduced activity of nuclear endonucleases in the liver cells, which attests to inhibition of apoptosis by the nuclear pathway. Injection of the toxicant enhanced the expression of intracellular molecular regulator of apoptosis Bcl-2 protein in the liver cells, which attested to triggering of proapoptotic signaling in these cells and organism’s attempts to limit the development of apoptosis by the mitochondrial mechanism via activation of Bcl-2-dependent anti-apoptotic defense.

Lipid peroxidation and mitochondrial superoxide dismutase-2 gene in adolescents with essential hypertension.

The study of LPO processes in adolescents of different races with essential hypertension revealed that Mongoloids exhibit oxidative stress by altering the level of the formation of diene conjugates, the primary LPO products. Caucasians increased the levels of both primary and end products of LPO, diene conjugates, and malondialdehyde. The revealed differences can be genetically determined because ethnic differences in the frequency of SOD2 gene Ala16Val polymorphism and its contribution to the biochemical phenotype were reported. The risk factors are Ala allele associated with increased MDA level for adolescent Caucasians and Val allele linked with decreased level of total antioxidant activity for adolescent Mongoloids.

Effect of maternal aseptic inflammation on the structural organization of extraembryonal organs and on the proliferative activity of embryonic liver and lung cells in rats

After 2 days of aseptic inflammation in pregnant rats the number of hematopoietic lineage cells in the embryonic liver decreased, while proliferative activity of cells in the embryonic lung increased. Degenerative changes were noted in the placenta.

Lipid Status and Predisposing Genes in Patients with Diabetes Mellitus Type 1 from Various Ethnic Groups

The peculiarities of HLA class II profile and lipid metabolism were examined in Buryat and Russian ethnic groups of patients with diabetes mellitus type 1. The incidence of type 1 haplotypes in HLA class II gene family was lower in Buryats than that in Russians. In comparison with Russians, the course of diabetes mellitus type 1 in Buryat patients was characterized with a lower content of total lipids, triacylglycerols, total cholesterol, and LDL, which probably explains a more favorable course of the disease in Buryat population.

Pathogenesis of Neurotoxicity of Acrylates Acrylonitrile and Acrylamide: from Cell to Organism

The incubation of 10 mM acrylamide (in vitro) with rat brain homogenate was followed by a decrease in catalase activity by 48% as soon as 5 min after addition of acrylate to the incubation medium. Activity of this enzyme remained low 30 min after the start of the experiment. Acute poisoning with this acrylate was accompanied by LPO activation in rat brain 24 h after injection. Exposure to acrylonitrile during occupational contacts with this monomer was followed by accumulation of adducts of acrylate with erythrocytic hemoglobin in human blood. In accordance with previously observed data, modern scheme of neurotropic effects of acrylonitrile and acrylamide was proposed. This scheme explained specific features of clinical syndromes induced by acute and chronic exposure to these toxic agents.

Effects of CYP1A2 Gene Polymorphisms on Antipyrine CYP1A2-Dependent Metabolism

The distribution of two CYP1A2 gene polymorphisms, CYP1A2*F and CYP1A2*D, was studied in a group of 38 men. Antipyrine elimination test was carried out and urinary cotinine was measured. The contribution of these CYP1A2 gene polymorphisms, age, and tobacco smoking to accumulation of three main antipyrine metabolites in the urine was evaluated by regression analysis. The impact of both studied polymorphisms was essential for urinary levels of 3-hydroxymethylantipyrine (metabolite most dependent on cytochrome P-4501A2) and hence, for functional activity of this isoform of the enzyme.

Nanostructure Changes in the Intervertebral Discs after Experimental Laser Irradiation

Laser-induced changes in the intervertebral discs were studied by the method of atomic force microscopy. Alteration of the proximal caudal intervertebral discs was modeled in rats: puncture and exposure to diode laser (2, 3, or 5 W) in constant or pulse regimens or only puncture (control). Nanostructure of disc surface was estimated by surface skewness, root mean square and average roughness, and coefficient of kurtosis. Maximum positive effect and signs of regenerative changes in the surface microstructure of the intervertebral discs were found after exposure to laser (2-3 W) in constant or pulse regimens.

Changes in Peripheral Blood Monocytes and Liver Macrophages in Male Rats after Benzo(a)pyrene Injection

Intraperitoneal injections of benzo(a)pyrene to male rats in a total dose of 60 mg/kg modified the production of ROS and the phagocytic potential of blood monocytes by modulating their potential bactericidal activity. The lysosomal system (particularly the secondary lysosomes) of liver macrophages was activated, which promoted fusion of the hydrolytic potentials of macrophages and monocytes. These results indicated that the toxin modulated the cellular immune homeostasis and the level of general nonspecific resistance.

Interhemispheric Interaction in Children with Autonomic Dysfunction of the Sinus Node

Electroencephalography was performed in 7-8- and 9-10-year-old pupils. Control group consisted of healthy children; experimental group consisted of children without signs of grade IV and V sinus arrhythmia at the age of 7-8 years, but with grade IV and V sinus arrhythmia at the age of 9-10 years. In primary school-aged children (7-8 years), manifestation of marked sinus arrhythmia is associated with disturbances in age-specifi c dynamics of interhemispheric interaction and with the formation, at the initial stage, of a rigid integrated system primarily due to functional intrahemispheric connections, the major contribution being made by the posterior associative cortical areas.

Effect of 3,4-Benzopyrene on Ultrastructure of Sinusoidal Cells of the Liver in Adult Male Rats

Reoganization of sinusoidal cells (endotheliocytes, Kupffer cells, and Ito cells) in the liver microregion of male rat liver exposed to 3,4-benzopyrene was studied. Synchronous activation of the lysosome-vacuole systems in Kupffer cells and endotheliocyte indicates cooperation of these cells in detoxification of benzopyrene and its metabolites. Ito cells lose lipid inclusions and actively proliferate; the appearance of intermediate forms between lipocytes and fibroblasts attests to activation of fibrogenesis in the liver.