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Antifouling (AF) coatings containing booster biocides are used worldwide as one of the most cost-effective ways to prevent the attachment of marine organisms to submerged structures. Nevertheless, many of the commercial biocides, such as Econea® (tralopyril), are toxic in marine environments. For that reason, it is of extreme importance that new efficient AF compounds that do not cause any harm to non-target organisms and humans are designed. In this study, we measured the half-maximal inhibitory concentration (IC50) of a promising nature-inspired AF compound, a triazolyl glycosylated chalcone (compound 1), in an immortalized human retinal pigment epithelial cell line (hTERT-RPE-1) and compared the results with the commercial biocide Econea®. We also investigated the effects of these biocides on the cellular lipidome following an acute (24 h) exposure using liquid chromatography quadrupole time-of-flight mass spectrometry (LC-Q-TOF/MS). Our results showed that compound 1 did not affect viability in hTERT-RPE-1 cells at low concentrations (1 μM), in contrast to Econea®, which caused a 40% reduction in cell viability. In total, 71 lipids were found to be regulated upon exposure to 10 µM of both compounds. Interestingly, both compounds induced changes in lipids involved in cell death, membrane modeling, lipid storage, and oxidative stress, but often in opposing directions. In general, Econea® exposure was associated with an increase in lipid concentrations, while compound 1 exposure resulted in lipid depletion. Our study showed that exposure to human cells at sublethal Econea® concentrations results in the modulation of several lipids that are linked to cell death and survival.
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Probing the Requirements of a Bruch's Membrane for Retinal Pigment Epithelial Cells
Age related macular degeneration (AMD) is the leading cause of blindness in developed countries. AMD occurs due to dysfunction of the retinal pigment epithelial (RPE) cell basement membrane, the Bruch’s membrane. Previous work in the lab demonstrated that retinal pigment epithelial cells preferred stiff substrates to soft ones, and that RGD-conjugated polyethylene glycol (PEG) hydrogels alone were not sufficient to support long term RPE cell health. There is evidence that epithelial and neural cells prefer laminin-derived peptides over fibronectin-derived peptides. Therefore, we examined the fate of RPE cells when seeded on PEG hydrogels conjugated with synthetic laminin peptides.
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- Award ID(s):
- 1752079
- PAR ID:
- 10139164
- Date Published:
- Journal Name:
- Biomedical Engineering Society
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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