Characterisation of stem and proliferating cells on the retina and lens of loach Misgurnus anguillicaudatus.

Abstract

The eye of the fish has a lifelong persistent neurogenesis unlike eye of mammals, so it's highly interesting to study retinal neurogenesis and its genetic control to give complete knowledge about the cause of this property in fish in comparison to mammals. We performed fluorescent in situ hybridisation for loach Misgurnus anguillicaudatus bmi1, msi1 and sox2 genes, which are used as an indicator of the sites of multipotent stem cells. Proliferating cell nuclear antigen (PCNA), bromodeoxyuridine (BRDU) and KI67 markers were used as indicators of proliferating cells and glial fibrillary acidic protein (GFAP) immunofluorescence was used for detection of the glial property of cells, as well as, immunohistochemistry detected the role of peroxisome proliferator-activated receptor (PPAR)α and γ in retinal neurogenesis. Our results determined that the lens and the retina of loach M. anguillicaudatus contain proliferative and pluripotent stem cells that have both glial and neuroepithelial properties, which add new cells continuously throughout life even without injury-induced proliferation. The PPARα has an essential function in providing energy supply for retinal neurogenesis more than PPARγ.