IMPACT OF NF-κB AND NRF2 TRANSCRIPTION FACTOR MODULATORS ON METABOLIC CHARACTERISTICS IN MANDIBLE BONES OF RATS DURING RECOVERY FROM INCOMPLETE FRACTURE UNDER CHRONIC ALCOHOL INTOXICATION

Abstract

This study aims at investigating the influence of specific modulators of NF-κB and Nrf2 transcription factors on oxidative-nitrosative stress indicators and bone biopolymer depolymerization in mandibular bone following incomplete fracture under chronic alcohol intoxication (CAI). Twenty-eight white male Wistar rats were divided into five groups: Group 1 comprised "falsely injured" rats, while Group 2 underwent incomplete mandibular fracture (IMF) under CAI exposure. Rats in groups 3 and 4 received intraperitoneal injections of ammonium pyrrolidinium dithiocarbamate, an inhibitor of NF-κB activation, in a dose of 76 mg/kg, and dimethyl fumarate, an Nrf2 inducer, in a dose of 15 mg/kg three times a week for 14 days following the modeling of IMF under CAI exposure. The activity of total NO synthase, including its constitutive and inducible isoforms, along with ornithine decarboxylase, and concentrations of peroxynitrites of alkaline and alkaline-earth metals, free hydroxyproline, N-acetylneuraminic, and hexuronic acids were assessed in the homogenate of the standard mandible area using a spectrophotometric method. The findings have demonstrated that the administration of ammonium pyrrolidine dithiocarbamate and dimethyl fumarate notably decreased the activity of NO synthase (primarily its inducible isoform) and the concentration of peroxynitrite in the mandibular bone homogenate, while increasing the activity of ornithine decarboxylase, a key enzyme in polyamine biosynthesis. Furthermore, under experimental conditions, the use of ammonium pyrrolidine dithiocarbamate and dimethyl fumarate limited the depolymerization of bone biopolymers (collagen, glycoproteins, and proteoglycans), thereby facilitating effective reparative osteogenesis.