INTRODUCTION

The neurodegenerative process with damage to axons and oligodendrocytes is thought to be the cause of permanent neurological impairment and disability; this is a key feature of the disease multiple sclerosis (MS).[1,2] At present, most available MS therapies are thought to exert their effects through immunomodulatory or immunosuppressive functions.[3-5] Although these treatments are effective at inhibiting immune cell-driven inflammation and reducing the relapse rate, they are ineffective at controlling the predominantly neurodegenerative processes that occur later in the disease course.[6] Fumaric acid esters have been used since 1959 as a treatment for psoriasis.[7] Dimethyl fumarate (DMF) is currently approved by FDA as a first-line treatment for lowering relapse rates in MS.[8-11] DMF and monomethyl fumarate were able to activate the transcription factor nuclear factor-erythroid 2-related factor 2 pathways and subsequently induce the expression of antioxidant proteins.[12,13] Oxidative stress is one of the major factors in the pathogenesis of MS and is readily apparent within experimental autoimmune encephalomyelitis, a mouse model of MS, and also in MS lesions.[14] In recent years, many research has proved that new nanotechnology can be applied for the treatment and diagnosis of variety of immune-mediated diseases like MS. Solid lipid nanoparticles (SLNs) are a novel, nanocolloidal, biocompatible drug delivery systems with improved bioavailability and drug payload. These nanocolloidal systems have been recently explored for targeting central nervous system (CNS) and various neurological disorders. Taking cognizance to the challenges for neurological disorders, patient compliance, and enhanced efficacy, it was envisioned to formulate DMF loaded SLNs in an attempt to overcome these concerns. Further, the developed colloidal system was evaluated in vitro in human neuroblastoma cells and an established cuprizone animal model.