Inhibition of altered Orai1 channels in Müller cells protects photoreceptors in retinal degeneration

Glia. 2023 Nov;71(11):2511-2526. doi: 10.1002/glia.24429. Epub 2023 Aug 3.

Abstract

The expressions of ion channels by Müller glial cells (MGCs) may change in response to various retinal pathophysiological conditions. There remains a gap in our understanding of MGCs' responses to photoreceptor degeneration towards finding therapies. The study explores how an inhibition of store-operated Ca2+ entry (SOCE) and its major component, Orai1 channel, in MGCs protects photoreceptors from degeneration. The study revealed increased Orai1 expression in the MGCs of retinal degeneration 10 (rd10) mice. Enhanced expression of oxidative stress markers was confirmed as a crucial pathological mechanism in rd10 retina. Inducing oxidative stress in rat MGCs resulted in increasing SOCE and Ca2+ release-activated Ca2+ (CRAC) currents. SOCE inhibition by 2-Aminoethoxydiphenyl borate (2-APB) protected photoreceptors in degenerated retinas. Finally, molecular simulations proved the structural and dynamical features of 2-APB to the target structure Orai1. Our results provide new insights into the physiology of MGCs regarding retinal degeneration and shed a light on SOCE and Orai1 as new therapeutic targets.

Keywords: MD simulations; Müller glial cells; Orai1; SOCE; molecular docking; oxidative stress; retina; retinal degeneration.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Calcium / metabolism
  • Calcium Channels* / metabolism
  • Calcium Signaling / physiology
  • Ependymoglial Cells / metabolism
  • Mice
  • ORAI1 Protein / metabolism
  • Rats
  • Retinal Degeneration* / drug therapy
  • Retinal Degeneration* / prevention & control
  • Stromal Interaction Molecule 1 / metabolism

Substances

  • Calcium Channels
  • Calcium
  • ORAI1 Protein
  • Stromal Interaction Molecule 1
  • Orai1 protein, mouse
  • Orai1 protein, rat