Purchase this article with an account.
E. K. Vidro, B. B. Yendluri, T. Le-Thai, A. T. Tsin; Acrolein Upregulates VEGF via a SMAD3 Pathway, and Upregulates TGFβ2 in ARPE-19 Cells. Invest. Ophthalmol. Vis. Sci. 2010;51(13):6176.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
: Recent studies have linked the environmental toxin, acrolein, found in cigarette smoke, to retinal pigment epithelium (RPE) cell death and senescence seen in age-related macular degeneration (AMD), a condition that is accompanied by increased levels of VEGF and TGFβ2 in the RPE. Previous results from our lab have shown that 48 hour treatment with 50 µM acrolein increased the release of VEGF by 53%, so experiments were performed to explore the effect of acrolein on TGFβ2 secretion and the mechanism of VEGF upregulation by ARPE-19 cells treated with acrolein.
Confluent ARPE-19 cells were treated with 12.5, 25, or 50 µM acrolein for 48 hours, or treated with 50 µM acrolein after being pretreated for 24 hours with 2µM various inhibitors of cellular transduction pathways, i.e. ZM39923 (JAK3), SIS3 (SMAD3), PDTC (NFΚB), U0126 (MEK1/2), SB202190 (p38/MAPK), and staurosporine (PKC). Cytokines were quantified using ELISA. Viable cell number was quantified using a hemacytometer with trypan blue.
: 48-hour treatment of ARPE-19 with 12.5, 25, or 50 µM acrolein all significantly increased TGFβ2 release by 17.7, 55.7, and 97.5%, respectively. 24-hour pre-treatment of ARPE-19 with cell transduction inhibitors before the addition of 50µM acrolein showed that the inhibitor SIS3, a specific inhibitor of SMAD3 which mediates TGFβ2 signaling, significantly reduced the acrolein-induced increase of VEGF by 36.4%. Acrolein-induced increase of VEGF was further increased 34.8% by PDTC, 62.9% by U0126, and 149% by SB202190. Acrolein-mediated VEGF increase was not affected by ZM39923 or staurosporine.
These data suggest that VEGF upregulation by acrolein is at least partially mediated by TGFβ2, which is itself upregulated by acrolein.Upregulation of VEGF by acrolein is likely limited or controlled by various interactions provided by other cell transduction pathways, NFΚB, MEK1/2, and p38/MAPK, as inhibition of these pathways allowed VEGF secretion to be increased over the level caused by acrolein alone. Increased TGFβ2 and VEGF observed in AMD can be partially explained by the action of the reactive aldehyde acrolein on the RPE.
This PDF is available to Subscribers Only