Effect of Aqueous-alcoholic Extract of Aloe vera on Retinal Tissue Changes in Rats with Experimental Multiple Sclerosis
Author(s): Soghra Gholami, Meimanat Khorram
Multiple Sclerosis is a chronic inflammatory disease of the central nervous system and demyelination of the central and the peripheral nerves, axonal damage and their loss are considered as the most important symptoms of it. As a result, multiple neurological disorders including visual impairments are observed by incidence of the disease. Some have stated that retinal impairment occurs due to the production of free radicals in patients with MS. Therefore, use of antioxidants may reduce retinal damages caused by MS disease in these patients. So, the aim of this study is to investigate the effects of aqueous-alcoholic extract of Aloe vera on retinal tissue changes in rats with experimental MS. Methods: To do this research, 60 male Wistar rats were randomly divided into 6 groups of 10 each, which included: control group (received water and food only), group 2 (received 200 mg/kgBW Aloe vera extract), group 3 (received 400 mg/kgBW Aloe vera extract), group 4 (the rats with myelin oligodendrocyte glycoprotein (MOG) peptide-induced MS), group 5 (the rats with experimental MS, which received 200 mg/kgBW of Aloe vera extract) and group 6 (the rats with experimental MS, which received 400 mg/kgBW of Aloe vera extract). At the end of the experiment, all of the rats were kept under deep anesthesia and the retinas were isolated for microscopic examinations. They were then placed in buffered formalin to carry out histological process and hematoxylin-eosin staining on them. Microscopic study includes measurement of retinal thickness and measurement of the thickness of retinal various layers including, PSL, ONL, INL, GCL, RNFL, IPL and OPL. Results: The results of this study showed that there was a significant decrease at 5% level of significance in the thickness of PSL, GCL, RNFL and the entire retina in the MS Groups compared to the Control Group. Also, there was a significant increase in the thickness of PSL, GCL, RNFL and the retina in the MS group received maximum dose of Aloe vera extract compared to the Control Group. There was also a significant decrease in PSL, RNFL and the retina thicknesses in the MS group received maximum dose of Aloe vera extract in comparison with the groups that received Aloe vera extract. Discussion and Conclusion: Finally, it can be said according to the research that thickness of the retina as well as its different layers is reduced by induction of MS, and treatment with Aloe vera gel extract will influence on the absence of change in these factors and on improvement of them.