Systemic taurine treatment provides neuroprotection against retinal photoreceptor degeneration and visual function impairments

Abstract

Ye Tao,*,1,2 Miao He,*,3 Qinghua Yang,1 Zhao Ma,3 Yingxin Qu,1 Wen Chen,3 Guanghua Peng,1 Dengke Teng41Department of Physiology, Basic Medical College, Zhengzhou University, Zhengzhou 450001, People’s Republic of China; 2Lab of Visual Cell Differentiation, Basic Medical College, Zhengzhou University, Zhengzhou 450001, People’s Republic of China; 3Department of Neurosurgery, Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430014, People’s Republic of China; 4Department of Ultrasound, China-Japan Union Hospital of Jilin University, Changchun, People’s Republic of China*These authors contributed equally to this workObjective: Retinitis pigmentosa causes progressive photoreceptor degeneration in the subjects while no clinical therapy exists. The present study sought to evaluate the potential protective effects of taurine on a pharmacologically induced RP animal model.Methods: Photoreceptor degeneration in mice was induced by an intraperitoneal injection of N-methyl-N-nitrosourea (MNU). The MNU-administrated mouse received taurine treatment and then they were examined by electroretinography, spectral-domain optical coherence tomography, optokinetic test, and histological and immunohistochemistry assay.Results: Prominent taurine deficiency was found in the retinas of MNU-administered mice. Intravenous taurine treatment increased significantly the retinal taurine level. Morphological studies showed that taurine could alleviate the retinal disorganizations in the MNU-induced mice. Taurine also ameliorated the visual impairments in the MNU-induced mice as evidenced by functional examinations. Immunostaining experiments demonstrated that both the M-cone and S-cone populations in the degenerative retinas are rescued by taurine. In particular, the M-cone photoreceptors in superior-temporal quadrant and the S-cone photoreceptors in inferior-nasal quadrant were preferentially rescued. Mechanism study showed that the photoreceptor apoptosis and oxidative stress in the degenerative retina were effectively alleviated by taurine treatment.Conclusion: Taurine is protective against the MNU-induced photoreceptor degeneration. Systemic taurine administration may act as a promising therapeutic potion for retinopathies with chronic cycle.Keywords: neural degeneration, retina, therapeutics

Keywords

• Neural degeneration
• Retina
• Therapeutics;