Effects of Green Tea Epigallocatechin-3-Gallate (EGCG) On Proteolipid Protein (PLP) and Oligodendrocyte Transcription Factor 1 (Olig1) Expression in the Cerebral Cortex of Cuprizone Induced Multiple Sclerosis Mice; A Western Blot Study

Background: The cuprizone multiple sclerosis (MS) animal model is characteristic for toxic demyelination and represents a reversible demyelination and remyelination system. It has been shown that green tea epigallocatechin-3- gallate (EGCG) might be effective in improving the symptoms and pathological conditions associated with autoimmune inflammatory diseases in several animal models. Objectives: In this study the effects of EGCG on proteolipid protein (PLP) and oligodendrocyte transcription factor 1 (Olig1) expression in the cerebral cortex of murine model of cuprizone-induced demyelination was investigated. Materials and Methods: C57BL/6 mice were treated by cuprizone for six weeks in order to induce demyelination. Immediately after the cessation of cuprizone the animals were divided into 6 groups (n=10 for each groups). The first two groups was injected intraperitoneally (IP) by EGCG in the amount of 50 mg/kg /daily body weight for 2 and 4 weeks. The second two groups (SHAM) was injected IP by phosphate-buffered saline (PBS) for 2 and 4 weeks and the third two groups was left without injection as controls. After two and four weeks the mice were killed and the cerebral cortex was collected and the expression of PLP and Olig1 was studied by Western blotting. Results:The results showed that there is a significant increases in PLP and Olig1 expression among the EGCG treated group as compared to the SHAM and control groups (p<0.0001). Conclusion: It is concluded that EGCG increases PLP and Olig1 expression in the cerebral cortex of mouse model of MS induced by cuprizone.