These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: The involvement of PI3K-mediated and L-VGCC-gated transient Ca2+ influx in 17β-estradiol-mediated protection of retinal cells from H2O2-induced apoptosis with Ca2+ overload. Author: Feng Y, Wang B, Du F, Li H, Wang S, Hu C, Zhu C, Yu X. Journal: PLoS One; 2013; 8(11):e77218. PubMed ID: 24223708. Abstract: Intracellular calcium concentration ([Ca(2+)]i) plays an important role in regulating most cellular processes, including apoptosis and survival, but its alterations are different and complicated under diverse conditions. In this study, we focused on the [Ca(2+)]i and its control mechanisms in process of hydrogen peroxide (H2O2)-induced apoptosis of primary cultured Sprague-Dawley (SD) rat retinal cells and 17β-estradiol (βE2) anti-apoptosis. Fluo-3AM was used as a Ca(2+) indicator to detect [Ca(2+)]i through fluorescence-activated cell sorting (FACS), cell viability was assayed using MTT assay, and apoptosis was marked by Hoechst 33342 and annexin V/Propidium Iodide staining. Besides, PI3K activity was detected by Western blotting. Results showed: a) 100 μM H2O2-induced retinal cell apoptosis occurred at 4 h after H2O2 stress and increased in a time-dependent manner, but [Ca(2+)]i increased earlier at 2 h, sustained to 12 h, and then recovered at 24 h after H2O2 stress; b) 10 μM βE2 treatment for 0.5-24 hrs increased cell viability by transiently increasing [Ca(2+)]i, which appeared only at 0.5 h after βE2 application; c) increased [Ca(2+)]i under 100 µM H2O2 treatment for 2 hrs or 10 µM βE2 treatment for 0.5 hrs was, at least partly, due to extracellular Ca(2+) stores; d) importantly, the transiently increased [Ca(2+)]i induced by 10 µM βE2 treatment for 0.5 hrs was mediated by the phosphatidylinositol-3-kinase (PI3K) and gated by the L-type voltage-gated Ca(2+) channels (L-VGCC), but the increased [Ca(2+)]i induced by 100 µM H2O2 treatment for 2 hrs was not affected; and e) pretreatment with 10 µM βE2 for 0.5 hrs effectively protected retinal cells from apoptosis induced by 100 µM H2O2, which was also associated with its transient [Ca(2+)]i increase through L-VGCC and PI3K pathway. These findings will lead to better understanding of the mechanisms of βE2-mediated retinal protection and to exploration of the novel therapeutic strategies for retina degeneration.[Abstract] [Full Text] [Related] [New Search]