No abstract

Fingolimod (FTY720) is a sphingosine 1‐phosphate (S1P) receptor analog, which has been approved as an oral immunomodulator for treating relapsing–remitting multiple sclerosis. This drug prevents lymphocyte egression from lymph nodes and reduces the infiltration of inflammatory mediators into the central nervous system. Based on its lipophilic nature, FTY720 passes through the blood–brain barrier and can directly affect neural cells. A notably different subtype of S1P receptors expresses in neural cells, which suggests FTY720 is a drug capable of affecting neural cells. Oligodendrocytes (OLs) are considered as the primary target cells in MS. Remyelination is a process including the proliferation of neural progenitors and oligodendrocyte precursor cells, their migration to the lesion site and their differentiation to mature oligodendrocytes. Experimental and clinical studies have described the impact of FTY720 on endogenous remyelination elements. In this review, we will explain the current clinical and experimental evidence that exists on the effects of FTY720 on remyelination and the underlying mechanisms.

No abstract

Oligodendrocyte precursor cells (OPCs) are considered as the main cell source for myelination in the central nervous system. Following demyelination, proliferation, migration, and differentiation capability of endogenous OPCs remarkably increase leading to remyelination in damaged areas. Despite the beneficial impacts of resident OPCs for myelin repair, the capacity of endogenous repair is low and insufficient.Therefore, several strategies have been developed to improve endogenous myelin repair. Although stem cell therapy has been introduced as a promising strategy for neurodegenerative disorders, but several limitations such as cell rejection, teratoma formation, and ethical concerns have hampered the extensive application of stem cells in clinic. In recent years, direct conversion of fully differentiated somatic cells into desired cells in the lesion area has opened a new era in regenerative medicine. In addition to direct reprogramming of somatic cells to neurons, recent evidence have also demonstrated that somatic cells, including fibroblasts and astrocytes, can be directly reprogrammed to OPC-like cells by overexpression of some specific transcription factors, microRNAs, or application of small molecules. Interestingly, induced OPCs differentiated to myelinating oligodendrocytes that could effectively ensheath the host axons. In the present review article, the current advancements in direct conversion of somatic cells towards oligodendroglial cells have been discussed both in vitro and in vivo. K E Y W O R D S direct reprogramming, endogenous remyelination, fully differentiated cells, myelin-forming cells, oligodendrocyte precursor cells

No abstract

No abstract

Introduction: Chronic stress, which has been prevalent in human life, induce structural changes in the hippocampus. Depression and impairment of memory are serious comorbidities of chronic stress. In this study, we evaluated the impact of an Iranian honey pretreatment on memory deficit, depression and the hippocampal neuronal loss in the chronic unpredictable mild stress (CUMS) model. Methods: Adult male Wistar rats were divided into the control groups that received water or honey (0.2 or 2g/kg) and CUMS groups that subjected different, randomly and unpredictable mild stressors for 4 weeks. Ten days before starting the CUMS procedures, the animals received honey (0.2 or 2g/kg, daily, orally), which was continued until sacrificing. Morris water maze and sucrose performance tests were used to evaluate the spatial learning and memory and depressive-like behavior in the animals respectively. Hippocampus and whole brain samples were collected for further biochemical and histological analysis. Results: Honey reversed the depression-like behavior and ameliorated the spatial memory deficit induced by CUMS. Also, honey decreased cell death in the hippocampus and reduced the malondialdehyde level in treated animals. Conclusion: These results revealed that honey diminished learning and memory deficits and depression in chronic stress conditions.

No abstract