Protective effect of Glycyrrhizin on cuprizone-induced model of multiple sclerosis in male C57BL/6 mice.

This research focused on assessing the protective effect of glycyrrhizin in male C57BL/6 mice with cuprizone-induced (CPZ) multiple sclerosis (MS). Forty male C57BL/6 mice were divided into four experimental groups. The control group was given the regular diet. In group 2, mice were administered a diet that included 0.2% (w/w) CPZ blended with ground chow for 4 weeks (Zhu et al., 2021). In group 3, mice were given glycyrrhizin (400 mg/kg) by mouth daily for 4 weeks. In group 4, mice were given a diet containing 0.2% CPZ and glycyrrhizin (400 mg/kg) by mouth for 4 weeks. Following the occurrence of the MS sign, reflexive motor behavior and levels of serum antioxidants were evaluated. According to the results, the administration of CPZ notably reduced rotarod duration, frequency of crossings in the open field test (OFT), hindlimb foot angle, suspension of front and hind limbs, as well as grip strength (P < 0.05). The administration of CPZ notably raised serum malondialdehyde (MDA), tumor necrosis factor (TNF-α), and interleukin-1 beta (IL-1β), while simultaneously lowering superoxide dismutase (SOD), glutathione peroxidase (GPX), and catalase (TAS) levels (P < 0.05). Glycyrrhizin notably enhanced stay duration on rotarod, quantity of crossings in OFT, hindlimb foot angle, front- and hindlimb suspension, and grip strength (P < 0.05). Glycyrrhizin notably lowered serum MDA, TNF-α, and IL-1β, while elevating SOD, GPX, and TAS levels (P < 0.05). These findings indicated that glycyrrhizin offers a protective effect against CPZ-induced multiple sclerosis in mice.