Fleming Thomas, Martinez-Moreno Carlos G, Carranza Martha, Luna Maricela, Harvey Steve, Arámburo Carlos
Department of Physiology, University of Alberta, Edmonton T6G 2H7, Canada.
Departamento de Neurobiología Celular y Molecular, Instituto de Neurobiología, Campus Juriquilla, Universidad Nacional Autónoma de México, Querétaro, Qro 76230, Mexico.
Gen Comp Endocrinol. 2018 Sep 1;265:111-120. doi: 10.1016/j.ygcen.2018.02.011. Epub 2018 Feb 15.
There is increasing evidence that suggests a possible role for GH in retinal development and synaptogenesis. While our previous studies have focused largely on embryonic retinal ganglion cells (RGCs), our current study demonstrates that GH has a synaptogenic effect in retinal primary cell cultures, increasing the abundance of both pre- (SNAP25) and post- (PSD95) synaptic proteins. In the neonatal chick, kainate (KA) treatment was found to damage retinal synapses and abrogate GH expression. In response to damage, an increase in Cy3-GH internalization into RGCs was observed when administered shortly before or after damage. This increase in internalization also correlated with increase in PSD95 expression, suggesting a neuroprotective effect on the dendritic trees of RGCs and the inner plexiform layer (IPL). In addition, we observed the presence of PSD95 positive Müller glia, which may suggest GH is having a neuroregenerative effect in the kainate-damaged retina. This work puts forth further evidence that GH acts as a synaptogenic modulator in the chick retina and opens a new possibility for the use of GH in retinal regeneration research.
越来越多的证据表明生长激素（GH）在视网膜发育和突触形成中可能发挥作用。虽然我们之前的研究主要集中在胚胎视网膜神经节细胞（RGCs）上，但我们目前的研究表明，GH在视网膜原代细胞培养中具有突触形成作用，可增加突触前（SNAP25）和突触后（PSD95）蛋白的丰度。在新生雏鸡中，发现给予 kainate（KA）会损害视网膜突触并消除GH表达。在损伤后不久给予Cy3-GH，观察到RGCs中Cy3-GH内化增加。这种内化增加也与PSD95表达增加相关，表明对RGCs的树突和内网状层（IPL）具有神经保护作用。此外，我们观察到存在PSD95阳性的穆勒胶质细胞，这可能表明GH在KA损伤的视网膜中具有神经再生作用。这项工作进一步证明了GH在雏鸡视网膜中作为突触形成调节剂的作用，并为GH在视网膜再生研究中的应用开辟了新的可能性。
