Details

Autor(en) / Beteiligte

• Eamegdool, Steven S.
• Sitiwin, Ephrem I.
• Cioanca, Adrian V.
• Madigan, Michele C.

Titel

Extracellular matrix and oxidative stress regulate human retinal pigment epithelium growth

Ist Teil von

• Free radical biology & medicine, 2020-01, Vol.146, p.357-371

Ort / Verlag

United States: Elsevier Inc

Erscheinungsjahr

2020

Quelle

Access via ScienceDirect (Elsevier)

Beschreibungen/Notizen

• Age-related macular degeneration (AMD), the most common cause of vision loss with ageing, is characterised by degeneration of the photoreceptors and retinal pigment epithelium (RPE) and changes in the extracellular matrix (ECM) underlying the RPE. The pathogenesis of AMD is still not fully understood. In this study we investigated the in vitro growth and function of primary human RPE cells in response to different ECM substrates, including nitrite-modified ECM. We initially confirmed the presence of disorganised retinal glial and photoreceptor cells, marked retinal cytoplasmic and Bruch's membrane expression of nitro-tyrosine (an oxidative stress marker) and increased numbers of Iba1+ macrophages/microglia in human donor eye sections (aged and AMD) using multi-marker immunohistochemistry (n = 3). Concurrently, we utilised two-photon microscopy to reveal topographical changes in flatmounts of RPE-associated ECM and in the underlying choroid of aged and AMD donor eyes (n = 3). To recapitulate these observations in vitro, we then used primary human RPE cells to investigate how different ECM proteins, including nitrite cross-linked RPE-secreted ECM, modified RPE cell growth and function. Collagen I or IV increased RPE attachment and spreading two-to three-fold, associated with significantly increased cell migration and proliferation, consistent with a preferential interaction with these matrix substrates. Primary human RPE cells grown on collagen I and IV also showed increased secretion of pro-inflammatory cytokines, MCP-1 and IL-8. Nitrite-modification of RPE-secreted ECM (simulating ageing of Bruch's membrane) significantly reduced in vitro RPE attachment to the ECM and this was mitigated with collagen IV coating of the modified ECM. Taken together, our observations confirm the importance of RPE-ECM interactions for normal RPE growth and function, and for inducing RPE secretion of pro-inflammatory cytokines. Furthermore, the findings are consistent with ageing and/or oxidative stress-induced disruption of RPE-ECM interactions contributing to the pathogenesis of AMD. [Display omitted] •RPE-Bruch's membrane ECM interface of AMD human eyes showed differences in 2 photon fluorescent lifetime signatures.•Collagen I or collagen IV surface coating enhanced in vitro growth and survival of primary human RPE cells.•Secretion of pro-inflammatory cytokines (MCP-1, IL-8) are affected by cellular interactions with the ECM.•Collagen I or collagen IV addition to nitrite modified RPE-derived ECM re-established in vitro RPE-ECM cellular interactions.•Oxidative-induced changes to Bruch's membrane ECM may contribute to early change in age-related macular degeneration (AMD).