OLR1 scavenger receptor knockdown affects mitotic gene expression but is dispensable for oxidized phospholipid- mediated stress signaling in SZ 95 sebocytes

Publication date: Available online 2 November 2017 Source:Mechanisms of Ageing and Development Author(s): Ionela-Mariana Nagelreiter, Masomeh Parvardeh, Marie-Sophie Narzt, Lucian Beer, Christopher Kremslehner, Ximena Maria Muresan, Johannes Grillari, Christos C. Zouboulis, Erwin Tschachler, Florian Gruber Phospholipid oxidation products (OxPL) are versatile stress signaling mediators in the skin. These lipid signaling molecules can be generated non-enzymatically or enzymatically by ultraviolet light, the major extrinsic skin aging factor. OxPL regulate cytoprotective, immunological and metabolic adaptation of the skin to oxidant stress. We here investigated whether the scavenger receptor Oxidized Low Density Lipoprotein Receptor 1 (OLR1, LOX-1) would have a function in cutaneous oxPL signaling. We found, that OLR1 is expressed in several cutaneous cell types, most prominently in cells of the sebaceous gland and in keratinocytes. We repressed OLR1 expression with siRNA in SZ95 sebocytes, exposed cells to oxidized 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphocholine (PAPC) and performed transcriptomic profiling. Bioinformatic analysis revealed that OxPL exposure induced the Nrf2 antioxidant stress response and aldosterone signaling. The analysis also revealed that OLR1 is not required for the transcriptional regulation induced by oxidized PAPC but interestingly, OLR1 knockdown affected expression of CNN2, HMRR, ITGB6 and KIF20A, all genes governing cell prolifera...
Source: Mechanisms of Ageing and Development - Category: Geriatrics Source Type: research