Oxidative stress in retinal pigment epithelium impairs stem cells: a vicious cycle in age-related macular degeneration

Mol Cell Biochem. 2021 Sep 17. doi: 10.1007/s11010-021-04258-3. Online ahead of print.ABSTRACTAging, chronic oxidative stress, and inflammation are major pathogenic factors in the development and progression of age-related macular degeneration (AMD) with the loss of retinal pigment epithelium (RPE). The human RPE contains a subpopulation of progenitors (i.e., RPE stem cells-RPESCs) whose role in the RPE homeostasis is under investigation. We evaluated the paracrine effects of mature RPE cells exposed to oxidative stress (H2O2) on RPESCs behavior through co-cultural, morphofunctional, and bioinformatic approaches. RPESCs showed a decline in proliferation, an increase of the senescence-associated β-galactosidase activity, the acquisition of a senescent-like secretory phenotype (SASP), and the reduction of their stemness and differentiation competencies. IL-6 and Superoxide Dismutase 2 (SOD2) seem to be key molecules in RPESCs response to oxidative stress. Our results get insight into stress-induced senescent-associated molecular mechanisms implicated in AMD pathogenesis. The presence of chronic oxidative stress in the microenvironment reduces the RPESCs abilities, inducing and/or maintaining a pro-inflammatory retinal milieu that in turn could affect AMD onset and progression.PMID:34535868 | DOI:10.1007/s11010-021-04258-3
Source: Molecular and Cellular Biochemistry - Category: Biochemistry Authors: Source Type: research