Semi-quantitative analysis of the effects of cyclosporine on remyelination following gliotoxic injection in the brainstem

• Published in: Arquivos de neuro-psiquiatria 2011, Vol.69 (2B), p.377-383
• Main Authors: Bondan, Eduardo Fernandes, Martins, Maria de Fátima Monteiro, Branco, Alexandre Moraes Castelo, Lallo, Maria Anete
• Format: Article
• Language: English
• Subjects: Animals; análise semiquantitativa; Brain Stem - drug effects; brometo de etídio; ciclosporina; Cyclosporine - therapeutic use; células de Schwann; Demyelinating Diseases - chemically induced; Demyelinating Diseases - drug therapy; Demyelinating Diseases - pathology; Disease Models, Animal; Ethidium; Immunosuppressive Agents - therapeutic use; Myelin Sheath - drug effects; Myelin Sheath - physiology; Nerve Regeneration - drug effects; NEUROSCIENCES; Oligodendroglia - drug effects; oligodendróglia; PSYCHIATRY; Rats; Rats, Wistar; remielinização; sistema nervoso central; Time Factors
• ISSN: 0004-282X; 1678-4227; 1678-4227; 0004-282X
• DOI: 10.1590/S0004-282X2011000300021

The use of cyclosporine (CsA) has shown to induce an increase in the density of oligodendrocytes near remyelinating areas following the injection of ethidium bromide (EB), a demyelinating agent, in the rat brainstem. This study was designed in order to evaluate if CsA has the capacity of increasing remyelination. In this context, a comparison between the final balance of myelin repair in CsA treated and non-treated rats was assessed using a semi-quantitative method developed for documenting the extent and nature of remyelination in gliotoxic lesions. Wistar rats were submitted to intracisternal injection of 10 microliters of 0.1% EB. Some were treated during 31 days with CsA (group III--10 mg/kg/day by 7 days and, thereafter, 3 times a week, with a minimal interval of 48 hours) by intraperitonial route. Others were not treated with CsA (group I). A control group was planned receiving into the cisterna pontis 10 microliters of 0.9% saline solution and following after that the same CsA administration protocol (group II). Results clearly demonstrate that in vivo administration of CsA after EB-demyelinating lesions stimulated oligodendrocyte remyelination (mean remyelination scores of 3.72±0.25 for oligodendrocytes and 1.04±0.39 for Schwann cells) compared to non-treated animals (3.13±0.71 and 1.31±0.62, respectively), although the mechanisms by which this positive CsA effect occurs are unclear.