RESUMO
Our experiments aim to determine if decreasing the amount of phosphatidylcholine (PC) relative to phosphatidylethanolamine (PE) at the lipid droplet surface changes the localization of specific lipid droplet proteins. We manipulate lipid droplet phospholipids in both a cultured mouse hepatocyte (AML12) cell line and on synthetic lipid droplets. Decreasing the PC:PE ratio increases perilipin 2, decreases DGAT2, and does not change rab18 or lanosterol synthase levels on lipid droplets. These differences may be explained by the distinct structural motifs that mediate the protein-lipid droplet interactions.
RESUMO
The prenatal period is critical for auditory development; thus, prenatal influences on auditory development may significantly impact long-term hearing ability. While previous studies identified a protective effect of carotenoids on adult hearing, the impact of these nutrients on hearing outcomes in neonates is not well understood. The purpose of this study is to investigate the relationship between maternal and umbilical cord plasma retinol and carotenoid concentrations and abnormal newborn hearing screen (NHS) results. Mother-infant dyads (n = 546) were enrolled at delivery. Plasma samples were analyzed using HPLC and LC-MS/MS. NHS results were obtained from medical records. Statistical analysis utilized Mann-Whitney U tests and logistic regression models, with p ≤ 0.05 considered statistically significant. Abnormal NHS results were observed in 8.5% of infants. Higher median cord retinol (187.4 vs. 162.2 µg/L, p = 0.01), maternal trans-ß-carotene (206.1 vs. 149.4 µg/L, p = 0.02), maternal cis-ß-carotene (15.9 vs. 11.2 µg/L, p = 0.02), and cord trans-ß-carotene (15.5 vs. 8.0 µg/L, p = 0.04) were associated with abnormal NHS. Significant associations between natural log-transformed retinol and ß-carotene concentrations and abnormal NHS results remained after adjustment for smoking status, maternal age, and corrected gestational age. Further studies should investigate if congenital metabolic deficiencies, pesticide contamination of carotenoid-rich foods, maternal hypothyroidism, or other variables mediate this relationship.