Photoreceptor cell calcium dysregulation and calpain activation promote pathogenic photoreceptor oxidative stress and inflammation in prodromal diabetic retinopathy.

In this study, we test the hypothesis that diabetes promotes a greater than normal cytosolic calcium level in rod cells that activates a Ca2+-sensitive protease, calpain, resulting in oxidative stress and inflammation, two pathogenic factors of early diabetic retinopathy (DR). Nondiabetic and 2-months diabetic C57Bl/6J and calpain1 knockout (Capn1-/-) mice were studied; subgroups were treated with a calpain inhibitor (CI). Ca2+ content was measured in photoreceptors using Fura-2. Retinal calpain expression was studied by qTR-PCR and immunohistochemistry.

https://ajp.amjpathol.org/article/S0002-9440(21)00298-4/fulltext?rss=yes

Source: American Journal of Pathology - June 29, 2021 Category: Pathology Authors: Aicha Saadane, Yunpeng Du, Wallace B. Thoreson, Masaru Miyagi, Emma M. Lessieur, Jianying Kiser, Xiangyi Wen, Bruce A. Berkowitz, Timothy S. Kern Tags: Regular Article Source Type: research