Involvement of SDF1a and STAT3 in Granulocyte Colony-Stimulating Factor Rescues Optic Ischemia-Induced Retinal Function Loss by Mobilizing Hematopoietic Stem Cells

Systemic Cytokines in Retinopathy of Prematurity

Retinopathy of prematurity (ROP), a vasoproliferative vitreoretinal disorder, is the leading cause of childhood blindness worldwide. Although angiogenic pathways have been the main focus, cytokine-mediated inflammation is also involved in ROP etiology. Herein, we illustrate the characteristics and actions of all cytokines involved in ROP pathogenesis. The two-phase (vaso-obliteration followed by vasoproliferation) theory outlines the evaluation of cytokines in a time-dependent manner. Levels of cytokines may even differ between the blood and the vitreous. Data from animal models of oxygen-induced retinopathy are also valuable. Although conventional cryotherapy and laser photocoagulation are well established and anti-vascular endothelial growth factor agents are available, less destructive novel therapeutics that can precisely target the signaling pathways are required. Linking the cytokines involved in ROP to other maternal and neonatal diseases and conditions provides insights into the management of ROP. Suppressing disordered retinal angiogenesis via the modulation of hypoxia-inducible factor, supplementation of insulin-like growth factor (IGF)-1/IGF-binding protein 3 complex, erythropoietin, and its derivatives, polyunsaturated fatty acids, and inhibition of secretogranin III have attracted the attention of researchers. Recently, gut microbiota modulation, non-coding RNAs, and gene therapies have shown promise in regulating ROP. These emerging therapeutics can be used to treat preterm infants with ROP.

Ocular progenitor cells and current applications in regenerative medicines - Review

The recent emerging field of regenerative medicine is to present solutions for chronic diseases which cannot be sufficiently repaired by the body's own mechanisms. Stem cells are undifferentiated biological cells and have the potential to develop into many different cell types in the body during early life and growth. Self renewal and totipotency are the characteristic features of stem cells and it holds a promising result for treating various diseases like diabetic foot ulcer, heart diseases, lung diseases, Autism, Skin diseases, arthritis including eye disease. Failure of complete recovery of eye diseases and complications that follow conventional treatments have shifted search to a new form of regenerative medicine using Stem cells. The ocular progenitor cells are remarkable in stem cell biology and replenishing degenerated cells despite being present in low quantity and quiescence in our body has a high therapeutic value. In this paper we have review the applications on ocular progenitor stem cells in treatment of human eye diseases and address the strategies that have been exploited in an effort to regain visual function in the advance treatment of stem cells without any side effects and also present the significance in advance stem cell research.

Stem Cell Therapy for Treatment of Ocular Disorders

Sustenance of visual function is the ultimate focus of ophthalmologists. Failure of complete recovery of visual function and complications that follow conventional treatments have shifted search to a new form of therapy using stem cells. Stem cell progenitors play a major role in replenishing degenerated cells despite being present in low quantity and quiescence in our body. Unlike other tissues and cells, regeneration of new optic cells responsible for visual function is rarely observed. Understanding the transcription factors and genes responsible for optic cells development will assist scientists in formulating a strategy to activate and direct stem cells renewal and differentiation. We review the processes of human eye development and address the strategies that have been exploited in an effort to regain visual function in the preclinical and clinical state. The update of clinical findings of patients receiving stem cell treatment is also presented.

Proteomic Profiling Suggests Central Role Of STAT Signaling during Retinal Degeneration in the rd10 Mouse Model

The rd10 mouse is a model of retinitis pigmentosa characterized by the dysfunction of a rod-photoreceptor-specific phosphodiesterase. Compared to the rd1 mouse, retinal degeneration in the rd10 mouse begins later in age with a milder phenotype, making it ideal for investigating cell death and neuroprotective mechanisms. Alterations in the rd10 retina proteome at pre-, peak-, and postdegenerative time points were examined using a modified high-recovery filter-aided sample preparation (FASP) method in combination with label-free quantitative mass spectrometry, generating a proteomic data set on almost 3000 proteins. Our data confirmed a period of protein expression similar to age-matched wild-type mice predegeneration, with decreases in proteins associated with phototransduction and increases in signaling proteins at peak- and postdegenerative stages. A total of 57 proteins were differentially expressed in the rd10 retinae during peak-degeneration, compared to those in wild-type mice after stringent FDR correction (q < 0.05). Network analysis separated these proteins into one cluster of down-regulated photoreceptor proteins and one of up-regulated signaling proteins centered around GFAP, STAT3, and STAT1. This is the first study to identify alterations in STAT1 in the rd10 mouse, which were confirmed with gene expression and immunoblotting experiments, underpinning the efficacy of our approach. This unique proteomic data set on protein dynamics during retinal degeneration could serve as an information source for vision research in the future.

Retinal Cell Degeneration in Animal Models

The aim of this review is to provide an overview of various retinal cell degeneration models in animal induced by chemicals (N-methyl-d-aspartate- and CoCl₂-induced), autoimmune (experimental autoimmune encephalomyelitis), mechanical stress (optic nerve crush-induced, light-induced) and ischemia (transient retinal ischemia-induced). The target regions, pathology and proposed mechanism of each model are described in a comparative fashion. Animal models of retinal cell degeneration provide insight into the underlying mechanisms of the disease, and will facilitate the development of novel effective therapeutic drugs to treat retinal cell damage.

Identification of a novel neurotrophic factor from primary retinal Müller cells using stable isotope labeling by amino acids in cell culture (SILAC)

Retinal Müller glial cells (RMGs) have a primary role in maintaining the homeostasis of the retina. In pathological situations, RMGs execute protective and regenerative effects, but they can also contribute to neurodegeneration. It has recently been recognized that cultured primary RMGs secrete pro-survival factors for retinal neurons for up to 2 weeks in culture, but this ability is lost when RMGs are cultivated for longer durations. In our study, we investigated RMG supernatants for novel neuroprotective factors using a quantitative proteomic approach. Stable isotope labeling by amino acids in cell culture (SILAC) was used on primary porcine RMGs. Supernatants of RMGs cultivated for 2 weeks were compared with supernatants from cells that had already lost their protective capacity. Using this approach, we detected established neurotrophic factors such as transferrin, osteopontin, and leukemia inhibitory factor and identified C-X-C motif chemokine 10 (CXCL10) as a novel candidate neuroprotective factor. All factors prolonged photoreceptor survival in vitro. Ex vivo treatment of retinal explants with leukemia inhibitory factor or CXCL10 demonstrated a neuroprotective effect on photoreceptors. Western blots on CXCL10- and leukemia inhibitory factor-stimulated explanted retina and photoreceptor lysates indicated activation of pro-survival signal transducer and activator of transcription signaling and B-cell lymphoma pathways. These findings suggest that CXCL10 contributes to the supportive potential of RMGs toward retinal neurons.