RESUMO
MicroRNAs are small non-coding RNAs that post-transcriptionally regulate gene expression. We recently demonstrated that levels of miR-106b were significantly decreased in the vitreous and plasma of patients with neovascular age-related macular degeneration (AMD). Here we show that expression of the miR-106b-25 cluster is negatively regulated by the unfolded protein response pathway of protein kinase RNA-like ER kinase (PERK) in a mouse model of neovascular AMD. A reduction in levels of miR-106b triggers vascular growth both in vivo and in vitro by inducing production of pro-angiogenic factors. We demonstrate that therapeutic delivery of miR-106b to the retina with lentiviral vectors protects against aberrant retinal angiogenesis in two distinct mouse models of pathological retinal neovascularization. Results from this study suggest that miRNAs such as miR-106b have the potential to be used as multitarget therapeutics for conditions characterized by pathological retinal angiogenesis.
Assuntos
Neovascularização de Coroide/genética , Degeneração Macular/genética , MicroRNAs/genética , Neovascularização Retiniana/genética , Animais , Linhagem Celular , Movimento Celular/genética , Neovascularização de Coroide/patologia , Retinopatia Diabética , Modelos Animais de Doenças , Estresse do Retículo Endoplasmático/genética , Células Endoteliais , Queimaduras Oculares , Humanos , Terapia a Laser , Degeneração Macular/patologia , Camundongos , Oxigênio/toxicidade , Neovascularização Retiniana/patologia , Retinopatia da Prematuridade , Resposta a Proteínas não Dobradas/genética , eIF-2 Quinase/genética , eIF-2 Quinase/metabolismoRESUMO
Age-related macular degeneration in its neovascular form (NV AMD) is the leading cause of vision loss among adults above the age of 60. Epidemiological data suggest that in men, overall abdominal obesity is the second most important environmental risk factor after smoking for progression to late-stage NV AMD To date, the mechanisms that underscore this observation remain ill-defined. Given the impact of high-fat diets on gut microbiota, we investigated whether commensal microbes influence the evolution of AMD Using mouse models of NV AMD, microbiotal transplants, and other paradigms that modify the gut microbiome, we uncoupled weight gain from confounding factors and demonstrate that high-fat diets exacerbate choroidal neovascularization (CNV) by altering gut microbiota. Gut dysbiosis leads to heightened intestinal permeability and chronic low-grade inflammation characteristic of inflammaging with elevated production of IL-6, IL-1ß, TNF-α, and VEGF-A that ultimately aggravate pathological angiogenesis.