Oral administration of <i>Weissella</i> and <i>Pediococcus sp</i> alleviates formalin induced inflammation in rats by Cytokine Modulation

Abstract

This study was designed to study the cytokine modulatory activity of three lactic acid bacteria (LAB) strains, Weisella cibaria II-1-59, Weisella confusa JMC 1093, and Pediococcus pentosaceus DSM20336 isolated from a Nigerian locally fermented food condiment; “iru” using paw oedema acute inflammatory model induced with 1% formalin in Wistar rats. Rats were distributed into six groups (A-F). Rats in Groups A were neither administered formalin nor treated with LAB, while Group B received formalin injection only. Rats in Groups C, D, and E were  administered formalin and were treated orally with 2 × 10⁷ CFU/ml of Weisella cibaria II-1-59, Weisella confusa JMC 1093, and Pediococcus pentosaceus DSM20336 respectively, while Group F received diclofenac sodium treatment following administration of formalin. The dose of LAB strain used for the oral treatment was 2 × 10⁷ CFU/ml for all the groups while the dose of diclofenac sodium used was 150 mg/kg body weight of the rats. Paw thickness (mm) was checked at t = 0, 1, 4, 8, 24, 72, 168 and 336 h. Cytokine assay for C-reactive protein (CRP), Interleukin (IL-10) and Transforming growth factor (TGF-β) was performed on serum samples of the rats using Enzyme-linked immunosorbent assay (ELISA). Oral administration of W. cibaria II-1-59 showed the best significant decrease in the paw thickness of the rats, which was followed by P. pentosaceus DSM20336 and W. confusa JMC 1093 respectively, and was shown to be statistically significant at P<0.05. There was also a significant decrease (below standard 2000 pg/ml) in the secretion of pro-inflammatory biomarker (CRP) in all LAB treated groups at 1 hour, while there was an increase in the serum levels of anti-inflammatory cytokines IL-10 and TGF- β in Groups C-E rats which was maximally increased in W. confusa JMC 1093 treated rats. This study suggests that W. cibaria II-1-59, W. confusa JMC 1093 and P. pentosaceus DSM20336 possess anti-inflammatory potentials.

Keywords: Inflammation, Cytokines, Weisella, Formalin, Oedema, Pediococcus