Comparing palm oil-derived tocotrienol-rich fraction with alpha-tocopherol in changes in locomotion and histological appearance in a cuprizone-induced animal model of multiple sclerosis

Abstract

Aims: Alpha-tocopherol (AT) and tocotrienol (TT) are both naturally occurring forms of vitamin E found in palm oil. Previous studies found beneficial effects of AT in multiple sclerosis (MS) animal models. In the present study, the effects of palm oil-derived TT-rich fraction (TRF) and AT on the locomotor function, lipid peroxidation, and histological study of demyelination were compared in cuprizone (CPZ)-induced rat model of MS. Methods: Female Sprague-Dawley rats aged 8 weeks received pellets mixed with CPZ for a duration of 6 weeks, followed by 100 mg/kg AT (group AT, n = 10) daily and 60 mg/kg TRF (group TT, n = 10) daily and vehicle (group V, n = 10) through oral gavage for 2 weeks. Open field test (OFT) and beam walking test (BWT) were carried out every 10th day. The status of myelination in the corpus callosum was evaluated by Luxol fast blue (LFB) staining and immunohistochemical staining of myelin basic protein (MBP). Malondialdehyde (MDA) level was estimated using brain homogenate. Results: Compared with group V, total distance moved and movement speed increased by 42.6 and 52.9%, respectively in group TT (P < 0.05). Line crossing frequency increased by 39% (P < 0.05) and 36% (P < 0.05), respectively in groups TT and AT. Corpus callosum showed a maximum reduction of demyelinated areas and higher expression of MBP in group TT. MDA level in the cortex was significantly reduced in group AT. Conclusion: TRF improved locomotion and provided histological evidence of myelination in CPZ-withdrawn rats. AT reduced MDA levels in the cortex.