Light Stress-Induced Increase of Sphingosine 1-Phosphate in Photoreceptors and Its Relevance to Retinal Degeneration

• DOI: 10.3390/ijms20153670
• Publication Date: 2019-07-26T12:45:39Z
• Authors: Ryo Terao; Megumi Honjo; Takashi Ueta; Hideru Obinata; Takashi Izumi; Makoto Kurano; Yutaka Yatomi; Hideto Koso; Sumiko Watanabe; Makoto Aihara
• Keywords: Photoreceptor cell; Visual phototransduction; Sphingosine Kinase

Sphingosine 1-phosphate (S1P) is a potent lipid mediator that modulates inflammation and angiogenesis. In this study, we investigated the possible involvement of S1P in pathology light-induced retinal degeneration vivo vitro. The intracellular sphingosine kinase (SphK) activity photoreceptor cell line (661W cells) was significantly increased by exposure to light. enhancement SphK1 expression dependent on illumination, all-trans-retinal promoted expression. treatment reduced protein B (Akt) phosphorylation cleaved caspase-3, induced apoptosis. vivo, light enhanced outer segments photoreceptors. Intravitreal injection SphK inhibitor suppressed thinning nuclear layer ameliorated attenuation amplitudes a-waves b-waves electroretinograms during degeneration. These findings imply induces synthesis photoreceptors upregulating SphK1, which facilitated all-trans-retinal, causing Inhibition may be therapeutic target degeneration, including age-related macular