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Multiple sclerosis (MS) is commonest demyelinating disease among young adults. It demonstrates neurological dysfunctions in females more than males. Gonadal hormones have essential roles in maturation and differentiation of neurons and glial cells in both genders. The role of some gonadal female hormones such as progesterone has been well characterized on demyelination and remyelination in animal models. The role of androgens on neural system development and myelin maturation were identified. We previously observed that castration decreases the brain resistance against demyelinating insults and also reduces the subsequent repair. As the optic nerves and chiasm demyelination shows the hallmark characteristic in MS, inducing demyelination in optic apparatus, we have tried to find whether the effects of elimination of male gonadal hormones using gonadectomy could show the same, more or less changes in patterns of demyelination and repair comparing demyelinated females? Thus, to evaluate these alternations castrated male and female rats were compared by using visual evoked potentials and histological assessments on 2,7,14, and 28 days post lysolecithine (LPC) injection. Interestingly, we observed demyelination was started 2 day post lesion (dpl), reached to a maximum level at 7 and 14 dpl and then it partially but significantly reversed on 28 dpl. Demyelination and subsequent repair processes in both gonadectomized and female groups were shown almost the same patterns temporarily and in quality. Elimination of gonadal androgens could cause the male animals to undergone the same shape of de/remyelination compared female ones. In conclusion, differences between male and female demyelination and remyelination are substantially depending on male gonadal androgens. This work could be useful for understanding of the effects of sex hormones on demyelinating diseases and could offer fundamental information for repairing therapies in Multiple Sclerosis.

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Background: Recently, the use of probiotics in preventing and treating the immune system diseases through changes in blood factors has attracted the attention of researchers. Therefore, the aim of this study was to evaluate the effect of Lactobacillus plantarum and Bifidobacterium B94 on changes of blood factors, influencing the autoimmune system diseases.
Materials and Methods: The rats used in this study were divided into four groups (n=10 each), including control (saline), damage with Ethidium bromide (EB), L. plantarum and Bifidobacterium B94 treatment groups. In damage and treatment groups, a single dose of 3μL EB was directly injected into hippocampus of rats for inducing demyelization. Also, in control group, the same amount of saline was used. Then 2×10⁸ probiotic bacteria were administered by gavage for 28 days. Then serum calcium and cholesterol levels were measured. Data were analyzed by one-way ANOVA and Tukey post-hoc tests (p≤ .05).
Results: The results showed that level of blood serum calcium increased insignificantly in the L. plantarum and Bifidobacterium B94 treatment groups compared to control group.  Also, the level of blood serum cholesterol decreased insignificantly in both treatment groups compared to control group.
Conclusion: Probiotics are used for preventing and treating some of the common autoimmune diseases such as MS. Previous studies showed that probiotics affects some of the blood parameters such as calcium and cholesterol while decrease or increase in these parameters is effective in the improvement of MS.  Although no significant finding has been obtained in some of these studies, they have almost confirmed the recommendation of probiotic consumption.

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Objective: Demyelination of CNS axons occurs under pathological conditions such as multiple sclerosis and spinal cord injuries, but can be repaired by cell therapy. Within the CNS remyelination can be achieved by transplantation of neural stem cells (NSCs). NSCs are self-renewing cells that maintain the capacity to differentiate into CNS-specific cell types and can differentiate into the three main neural phenotypes: astroglia, oligodendroglia and neurons. They may also replace or repair diseased CNS tissue. Methods: Bone marrow stromal cells (BMSCs) were aseptically isolated from the tibia and femurs of young adult Sprague Dawley rats. BMSCs were evaluated by fibronectin and CD31 markers. BMSC-derived NSCs were evaluated by nestin and NF-68. An ethidium bromide-induced demyelinated dorsal column lesion was produced in young adult rats. Transplanting NSCs derived-BMSCs into demyelinated lesions after 3 days in adult rat spinal cords was done. Three weeks after transplantation of NSCs, the spinal cords were processed to evaluate remyelination by Luxol fast blue staining. Results: After passage 3, BMSCs were evaluated and the result, showed the percentage of immunoreactive cells to fibronectin (94.7±2.65), however BMSC-derived NSCs expressed nestin (86.15±0.64) and NF-68 (84.55±0.94) which correlated with fibronectin down regulation. Histologically, the lesions showed slightly irregular elongated areas and had an average length of 1336.36±39.43 µm. Transplanted NSCs were capable of eliciting remyelination. Conclusion: These data support the conclusion that transplantation of NSCs results in functional remyelination of a dorsal column lesion and have valuable applications in the treatment of neurodegenerative diseases such as spinal cord injuries.