Neuroprotective and antioxidant effects of Thalassia testudinum extract BM-21, against acrylamide-induced neurotoxicity in mice

Abstract

Context: Acrylamide (ACR) neurotoxicity is associated with the enhancement of lipid peroxidation and the reduction of the antioxidative capacity distal axon and nerve terminal regions. The aqueous ethanolic extract of the marine plant Thalassia testudinum, named BM-21, have shown antioxidant, anti-inflammatory and analgesic properties. Aims: To determine the neuroprotective and the antioxidant effects of BM-21, standardized to thalassiolin B content (5.8 ± 0.9%), on acrylamide (ACR)-induced distal axonopathy in male OF-1 mice. Methods: Animals were administered with ACR (70 mg/kg, s.c., 4 weeks), and BM-21 was co-administered p.o at the doses of 4, 40 and 400 mg/kg. The effect of BM-21 on neurobehavioral indexes (rota-rod test), compound muscle action potential (CMAP) of the sciatic nerve and oxidative stress parameters were investigated. Results: BM-21 significantly prevented the neurobehavioral sings of neurotoxicity and the alteration of CMAP amplitude and velocity. The lowest dose (4 mg/kg) failed to ameliorate these parameters whereas the highest dose (400 mg/kg) was the most active. BM-21 (400 mg/kg) significantly restored total hydroperoxides (THP) and glutathione (GSH) in the sciatic nerve as well as superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities. Additionally, the extract also modified THP, GSH and the activity of SOD in cerebellum and brain towards the standard values. Conclusions: BM-21 given at doses that prevented ACR-induced neurotoxicity also produced antioxidant effect in the sciatic nerve, cerebellum and brain. Thus, the neuroprotective activity of BM-21 in this model seems to be mediated at least partly by its antioxidative properties.