RESUMO
The effect of acute hypoxia on the occurrence of apoptosis in eye cells in rats placed in a pressure chamber was studied. Selective primary lesion of cells of the conjunctiva and the anterior corneal epithelium was found. A possible role of the simulated hypoxic conditions in the dry eye syndrome pathogenesis, which is accompanied by primary lesion of cells in the anterior eye surface tissues is discussed.
Assuntos
Apoptose/fisiologia , Túnica Conjuntiva/fisiopatologia , Córnea/fisiopatologia , Hipóxia/fisiopatologia , Animais , Benzimidazóis , Túnica Conjuntiva/patologia , Córnea/patologia , Dano ao DNA/fisiologia , Modelos Animais de Doenças , Síndromes do Olho Seco , Corantes Fluorescentes , Hipóxia/patologia , Marcação In Situ das Extremidades Cortadas , Masculino , Microscopia de Fluorescência , Pressão , Ratos Wistar , Convulsões/patologia , Convulsões/fisiopatologiaRESUMO
In this paper, we analyzed our own results and published data on the expression of regulatory genes encoding transcription factors Pax6/PAX6, Pitx2/PITX2, Fox1/FOXC1, Prox1/PROX1, Oct4/OCT4, Nanog/NANOG, and TGFß2 signaling protein during morphogenesis of the cornea in vertebrates. We considered the results obtained for the cornea of model animals, primarily mice, and human fetal cornea. The main possibility of establishing common mechanisms of eye development in vertebrates in health and disease is comparative studies of eye morphogenesis of humans and animal models.
Assuntos
Córnea/embriologia , Córnea/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento , Animais , Córnea/fisiologia , Proteínas do Olho/genética , Fatores de Transcrição Forkhead/genética , Proteínas de Homeodomínio/genética , Humanos , Camundongos , Morfogênese/genética , Proteína Homeobox Nanog , Fator 3 de Transcrição de Octâmero/genética , Fator de Transcrição PAX6 , Fatores de Transcrição Box Pareados/genética , Proteínas Repressoras/genética , Fatores de Transcrição/genética , Fator de Crescimento Transformador beta2/genética , Proteínas Supressoras de Tumor/genética , Vertebrados/genética , Vertebrados/crescimento & desenvolvimento , Proteína Homeobox PITX2RESUMO
The results of molecular-genetic mechanisms of regeneration in amphibians are reviewed. Based on the examples of traditional and well-studied models of the restoration of the retinas and lenses of eyes, as well as limbs and tails in amphibians, we analyze the current state of regeneration problems and questions linked to cell reprogramming, growth, and generate morphogenesis. The development of the Kol'tsov school of thought in the age of molecular-genetic approaches and methods are monitored. The contemporary interpretation of organ regeneration in terms of molecular-genetic regulation and a new look at the definition of regeneration as repeated development is proposed. We also emphasize the current problems that exist in that field of developmental biology and are caused by the many difficulties of genome sequencing and the introduction oftransgenesis in Urodela, the animal species with the highest regeneration abilities.
Assuntos
Regeneração/genética , Urodelos/genética , Animais , Reprogramação Celular , Extremidades/fisiologia , Cristalino/fisiologia , Morfogênese/genética , Cauda/fisiologia , Urodelos/fisiologiaRESUMO
Expression of genes and heat shock proteins in normal intact retina of the Spanish Ribbed Newt Pleurodeles waltl was studied using polymerase chain reaction, Western blot hybridization, and immunohistochemistry. It was shown that the proteins HSP70 and HSP90, as well as their encoding transcripts of relevant genes, are constitutively expressed in eye tissues. These proteins were distributed differentially, and they were characterized by expression of different levels in the retina: HSP70 dominated in the external retina, while HSP90 dominated in the internal one, in particular, in Muller glial cells and the optic nerve. Transcripts and heat shock proteins HSP70 and HSP90 were also found in the retinal pigment epithelium and eye growth zone.
Assuntos
Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP90/genética , RNA Mensageiro/genética , Retina/metabolismo , Transcrição Gênica , Animais , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Neuroglia/metabolismo , Nervo Óptico/metabolismo , Especificidade de Órgãos , Epitélio Pigmentado Ocular/metabolismo , Pleurodeles , RNA Mensageiro/metabolismo , Retina/citologiaRESUMO
Expression of transforming growth factor-ß2 was detected by PCR in the vitreous body, lens, retina, and ciliary-iris complex of human eye at early stages of fetal development. Immunochemical assay of the corresponding protein in eye tissues revealed a correlation between the localization of transforming growth factor-ß2 and the development of intraocular hyaloid vascular network, its regression, formation of the vitreous body, and development of definite retinal vessels.
