Role of tumour necrosis factor-α (TNFα) in the functional properties of hyalocytes

• Published in: British journal of ophthalmology Vol. 95; no. 2; pp. 261 - 265
• Main Authors: Hata, Yasuaki, Nakao, Shintaro, Kohno, Ri-ichiro, Oba, Kumiyo, Kita, Takeshi, Miura, Muneki, Sassa, Yukio, Schering, Alexander, Ishibashi, Tatsuro
• Format: Journal Article
• Language: English
• Published: BMA House, Tavistock Square, London, WC1H 9JR BMJ Publishing Group Ltd 01.02.2011; BMJ Publishing Group
• Subjects: Animals; Anti-Inflammatory Agents - pharmacology; Biological and medical sciences; Blotting, Western; Cattle; Cell Migration Assays; Cell Proliferation - drug effects; Cell Size; Cells, Cultured; Cytokines - drug effects; Cytokines - physiology; Dexamethasone - pharmacology; experimental and laboratory; hyalocytes; inflammation; Macrophages - drug effects; Macrophages - physiology; Medical sciences; Miscellaneous; Ophthalmology; Recombinant Proteins - antagonists & inhibitors; Recombinant Proteins - pharmacology; retina; Retinal Diseases - drug therapy; Retinal Diseases - physiopathology; Signal Transduction - drug effects; steroid; Tumor Necrosis Factor-alpha - antagonists & inhibitors; Tumor Necrosis Factor-alpha - pharmacology; Vitreoretinal diseases; vitreous; Vitreous Body - cytology; Ophthalmology; Properties; Tumor necrosis factor α; Cytokine
• ISSN: 0007-1161; 1468-2079
• DOI: 10.1136/bjo.2010.190322

Background/aimTumour necrosis factor-α (TNFα) is an inflammatory cytokine that is upregulated in various vitreoretinal diseases including uveitis and diabetic retinopathy. Recently, our studies have indicated that hyalocytes contribute to the pathogenesis of these diseases. However, the impact of TNFα on the functional properties of hyalocytes is unknown.MethodsHyalocytes were isolated from bovine eyes. Cellular proliferation, migration and gel contraction in response to TNFα and the other inflammatory cytokines were analysed by thymidine uptake, Boyden's chamber assay and collagen gel contraction assay, respectively. Furthermore, we estimated the effect of dexamethasone on these properties of hyalocytes.ResultsTNFα promoted proliferation, migration and gel contraction by hyalocytes. Dexamethasone inhibited TNFα-induced proliferation but not migration. Dexamethasone did not inhibit TNFα-induced gel contraction but further increased contraction. Furthermore, dexamethasone inhibited TNFα-induced extracellular signal-related kinase (ERK)1/2 phosphorylation in hyalocytes.ConclusionThis study indicates that TNFα in vitreous and retina causes activation of hyalocytes, and the activated hyalocytes contribute to the pathogenesis of inflammatory vitreoretinal diseases. Steroid treatment appears to inhibit the activation of hyalocytes in the early stages of the diseases, but might have adverse effects in the late stage through membrane contraction.