Macrophage dysfunction plays a pivotal role during neovascular proliferation in diseases of ageing including cancers, atherosclerosis and blinding eye disease. In the eye, choroidal neovascularization (CNV) causes blindness in patients with age-related macular degeneration (AMD). Here we report that increased IL10, not IL4 or IL13, in senescent eyes activates STAT3 signalling that induces the alternative activation of macrophages and vascular proliferation. Targeted inhibition of both IL10 receptor-mediated signalling and STAT3 activation in macrophages reverses the ageing phenotype. In addition, adoptive transfer of STAT3-deficient macrophages into eyes of old mice significantly reduces the amount of CNV. Systemic and CD163⁺ eye macrophages obtained from AMD patients also demonstrate STAT3 activation. Our studies demonstrate that impaired SOCS3 feedback leads to permissive IL10/STAT3 signalling that promotes alternative macrophage activation and pathological neovascularization. These findings have significant implications for our understanding of the pathobiology of age-associated diseases and may guide targeted immunotherapy.

Photoreceptor death is the endpoint of many blinding diseases. Identifying unifying pathogenic mechanisms in these diseases may offer global approaches for facilitating photoreceptor survival. We found that rod or cone photoreceptor-specific deletion of nicotinamide phosphoribosyltransferase (Nampt), the rate-limiting enzyme in the major NAD(+) biosynthetic pathway beginning with nicotinamide, caused retinal degeneration. In both cases, we could rescue vision with nicotinamide mononucleotide (NMN). Significantly, retinal NAD(+) deficiency was an early feature of multiple mouse models of retinal dysfunction, including light-induced degeneration, streptozotocin-induced diabetic retinopathy, and age-associated dysfunction. Mechanistically, NAD(+) deficiency caused metabolic dysfunction and consequent photoreceptor death. We further demonstrate that the NAD(+)-dependent mitochondrial deacylases SIRT3 and SIRT5 play important roles in retinal homeostasis and that NAD(+) deficiency causes SIRT3 dysfunction. These findings demonstrate that NAD(+) biosynthesis is essential for vision, provide a foundation for future work to further clarify the mechanisms involved, and identify a unifying therapeutic target for diverse blinding diseases.

Purpose. Resveratrol is known as one of the antioxidant polyphenols contained in red wine and grape skin. The purpose of the present study was to investigate the role of resveratrol in ocular inflammation in endotoxin-induced uveitis (EIU). methods. EIU was induced in male C57/B6 mice at the age of 6 weeks by a single intraperitoneal injection of lipopolysaccharide (LPS). Animals had received oral supplementation of resveratrol at the doses of 5, 50, 100, or 200 mg/kg for 5 days until LPS injection. Twenty-four hours after LPS administration, leukocyte adhesion to the retinal vasculature was examined with a concanavalin A lectin perfusion-labeling technique. Retinal and retinal pigment epithelium (RPE)-choroidal levels of intercellular adhesion molecule (ICAM)-1, monocyte chemotactic protein (MCP)-1, and 8-hydroxy-2′-deoxyguanosine (8-OHdG) and nuclear translocation of nuclear factor (NF)-κB p65 were evaluated by enzyme-linked immunosorbent assay. Retinal and RPE-choroidal activities of silent information regulator two ortholog (SIRT) 1 were measured by deacetylase fluorometric assay. results. Resveratrol pretreatment led to significant and dose-dependent suppression of leukocyte adhesion to retinal vessels of EIU mice compared with vehicle application. Protein levels of MCP-1 and ICAM-1 in the retina and the RPE-choroid of EIU animals were significantly reduced by resveratrol administration. Importantly, resveratrol-treated animals showed significant decline of retinal 8-OHdG generation and nuclear NF-κB P65 translocation, both of which were upregulated after EIU induction. RPE-choroidal SIRT1 activity, reduced in EIU animals, was significantly augmented by treatment with resveratrol. conclusions. Resveratrol prevented EIU-associated cellular and molecular inflammatory responses by inhibiting oxidative damage and redox-sensitive NF-κB activation.

Purpose.: To investigate the role of reactive oxygen species (ROS) as the prime initiators of the angiogenic response after alkali injury of the cornea and observe the effects of antioxidants in preventing angiogenesis. Methods.: The corneal epithelia of SOD-1–deficient mice or wild-type (WT) mice were removed after application of 0.15 N NaOH to establish the animal model of alkali burn. ROS production was semiquantitatively measured by dihydroethidium (DHE) fluorescence. Angiogenesis was visualized by CD31 immunohistochemistry. The effects of the specific NF-κB inhibitor DHMEQ, the antioxidant N-acetyl-l-cysteine (NAC), and hydrogen (H₂) solution were observed. Results.: ROS production in the cornea was enhanced immediately after alkali injury, as shown by increased DHE fluorescence (P < 0.01). NF-κB activation and the upregulation of vascular endothelial growth factor (VEGF) and monocyte chemoattractant protein-1 (MCP-1) were significantly enhanced (P < 0.01), leading to a significantly larger area of angiogenesis. Angiogenesis in SOD-1^−/− mice corneas were significantly higher in WT mice (P < 0.01), confirming the role of ROS. Pretreatment with the specific NF-κB inhibitor DHMEQ or the antioxidant NAC significantly reduced corneal angiogenesis by downregulating the NF-κB pathway (P < 0.01) in both WT and SOD-1^−/− mice. Furthermore, we showed that irrigation of the cornea with hydrogen (H₂) solution significantly reduced angiogenesis after alkali-burn injury (P < 0.01). Conclusions.: Immediate antioxidant therapy with H₂-enriched irrigation solution is a new potent treatment of angiogenesis in cornea to prevent blindness caused by alkali burn.