Effects of the Environmental Pollutant Acrylic Aldehyde on Renal Fibrosis

Friday, 13 February 2015
Exhibit Hall (San Jose Convention Center)
Sanjana J. Rane, duPont Manual High School, Prospect, KY
Cigarette smoke promotes renal fibrosis but the direct effects of acrolein (acrylic aldehyde), a constituent of cigarette smoke on renal fibrosis had not been determined. Heat shock protein 27 (Hsp27) is known to regulate renal fibrosis. Nuclear Factor Erythroid derived protein-2 (NF-E2) is a novel Hsp27-binding protein. Therefore, the purpose of my study was to determine the effects of acrolein exposure on renal fibrosis by examining NF-E2 expression, pro-fibrotic Connective Tissue Growth Factor (CTGF) expression, and induction of apoptosis in acrolein treated renal epithelial (HK-11) cells. I hypothesized that acrolein will induce renal fibrosis by altering CTGF expression and HK-11 cell apoptosis in a NF-E2 dependent manner. HK-11 cells were exposed to varying concentrations of acrolein (10 µM, 25 µM, 50 µM) for 24 hours and cell lysates were immunoblotted with anti-CTGF, anti-NF-E2, and anti-cleaved caspase-3 antisera. Exposure of HK-11 cells to acrolein significantly induced CTGF expression in a dose dependent manner with a concurrent decrease in NF-E2 expression. Increased NF-E2 expression was detected in acrolein treated HK-11 supernatants. The role of extracellular NF-E2 currently has not been determined. Acrolein also induced caspase-3 cleavage, and Hoechst staining demonstrated nuclear condensation indicative of apoptosis. Increasing acrolein concentration decreased HK-11 cell viability as documented by MTT reduction. Over-expression of NF-E2 inhibited CTGF expression and prevented HK-11 apoptosis by inhibiting caspase-3 cleavage.  Thus, my studies identified NF-E2 as novel regulator of acrolein-induced CTGF expression and HK-11 apoptosis. Therefore, inducers of NF-E2 expression may serve a therapeutic role in treating renal fibrosis.