Agmatine protects cultured retinal ganglion cells from tumor necrosis factor-alpha-induced apoptosis

Aims: We investigated the protective effects of agmatine against tumor necrosis factor (TNF)-alpha-induced apoptosis in transformed rat retinal ganglion cells (RGC-5 cell line). Main methods: The RGC-5 cells were exposed to 50 ng/mL TNF-alpha for 48 h with or without presence of 100 W agmatine as indicated. Cell viability was determined by lactate dehydrogenase (LDH) assay. Double staining with Hoechst 33342 and propidium iodide for morphological analysis was performed. Subsequently, using annexin V assay, the proportion of cells actively undergoing apoptosis was determined. Key findings: After 48 h of exposure to 50 ng/mL TNF-alpha, 17.00% of RGC-5 cells were lost, as evident by LDH assay. TNF-alpha-induced RGC-5 cell death was reduced to 8.14% with 100 mu M agmatine treatment. This observed cell loss was due to apoptotic cell death, as established by annexin V assay. Significance: Our results reveal that agmatine has neuroprotective effects against TNF-alpha-induced apoptosis in retinal ganglion cells in vitro. (C) 2008 Elsevier Inc. All rights reserved.