ROLE OF TRANSCRIPTIONAL FACTOR NF-κB IN DEVELOPMENT OF OXIDATIVE STRESS IN HEART OF RATS DURING SYSTEMIC INFLAMMATORY RESPONSE INDUCED BY BACTERIAL LIPOPOLYSACCHARIDE

Abstract

Systemic inflammatory response syndrome (SIRS) is a threatening complication that can lead to myocardial infarction. Activation of the nuclear transcription factor κB (NF-κB) plays an unambiguous role in the SIRS development. The purpose of this study is to determine the effect of NF-κB nuclear transcription factor activation on production of superoxide anion radical (O2•-), superoxide dismutase (SOD) and catalase activity, concentration of free malondialdehyde (MDA) in the heart of rats during SIRS modelling. The experiment was performed on 24 mature Wistar male rats weighing 180-220 g. Animals were divided into 3 groups consisting of 8 animals (control, SIRS group, NF-κB blockade group). SIRS was modelled by intraperitoneal administration of bacterial lipopolysaccharide (Pyrogenal) in a dose of 0.4 μg / kg 3 times a week in the first week; then once a week for 2 months. The blockade of NF-κB was performed by administration of ammonium pyrrolidine dithiocarbamate (PDTC) in a dose of 76 mg / kg. Production of O2•-, activities of SOD and catalase, concentration of MDA was investigated in 10% heart tissues homogenate. Induction of SIRS by Pyrogenal increases basic production of O2•- by 54.6% compared to the control group. Production of O2•- by microsomal electron transport chain (ETC) and NO synthase increases by 52.9%; production of O2•- by mitochondrial ETC increases by 38,9%. Activity of SOD increases by 1.86 times, activity of catalase increases by 1.53 times. The concentration of free MDA in heart tissues has grown by 81.2%. Blockade of the transcription factor NF-κB reduces basic production of O2•- by 38.9%; by microsomal ETC and NO synthase by 41%; by mitochondrial ETC by 22.2% compared to SIRS group. SOD activity decreases by 56.7%, while catalase activity does not statistically significantly change. The concentration of free MDA in heart tissues decreases by 31.4%. Activation of the nuclear transcription factor NF-κB in the heart of rats during SIRS induced by Pyrogenal leads to an increase in O2•- production with subsequent development of oxidative stress. Compensatory activation of antioxidant enzymes under these conditions is not able to prevent the development of oxidative stress in heart tissues.