Lactobacillus species modulates TNF-α and Nrf2 expression in carrageenan-induced rat paw oedema

Abstract

BackgroundThe buildup of activated immune cells at injury sites accelerates the production of free radicals and reactive oxygen species which further promotes oxidative stress, leading to an inflammatory response that can in turn intensify oxidative stress. This study evaluates the activity of three Lactobacillus species sourced from Nigerian locally fermented drink products for acute inflammatory regulation potentials in Wistar rats using paw oedema model induced by carrageenan. Material and methodsOedema was induced with 1% iota-carrageenan in experimental groups and thereafter received 5 × 107 CFU/mL of L. fermentum CIP 102980, L. fermentum NBRC 15885 and L. plantarum CIP 103151 treatments while positive control group received diclofenac sodium (150 mg/kg body weight of rats). The occurrence of inflammation, oxidative stress were assessed at intervals (t = 1, 4, 24, and 72 hrs) on rat paw tissues via biochemical estimation of NO, MPO, MDA and GSH. Routine haematoxylin and eosin stain was used to investigate neutrophil infiltration and immunostaining of tumour necrosis factor alpha (TNF-α) and nuclear factor erythroid 2–related factor 2 (Nrf2) was performed to evaluate inflammation and oxidative stress respectively. ResultsLactobacillus treated groups showed significant control to mitigate the influx of infiltrating neutrophils to rat paws, as well as interacting with non-enzymatic antioxidants (glutathione) to act as antioxidants by increasing their levels, regulating lipid peroxidation, nitric oxide and myeloperoxidase compared to diclofenac sodium group. LAB treatments also downregulated the production of TNF-α cytokine and upregulated Nrf2 compared to untreated group. ConclusionLactobacillus exert potent therapeutic benefits against oxidative stress damage and influx of neutrophil cells in inflamed rats.