In oil, free fatty acids (FFAs) are thought to be the preferred substrate for lipid oxidation although triacylglycerols (TAGs) are the predominant lipid class. We determined the preferential oxidation substrate (TAGs versus FFAs) in soybean oil heated at 100 °C for 24 h, after validating a method for quantifying esterified and free lipid oxidation products (i.e., oxylipins) with mass-spectrometry. Reaction velocities and turnover (velocity per unit substrate) of FFA, and free and TAG-bound (esterified) oxylipins were determined. FFA hydrolysis rate and turnover were orders of magnitude greater (16-4217 fold) than that of esterified and free oxylipin formation. The velocity and turnover of TAG-bound oxylipins was significantly greater than free oxylipins by 282- and 3-fold, respectively. The results suggest that during heating, TAGs are preferentially oxidized over FFAs, despite the rapid hydrolysis and availability of individual FFAs as substrates for oxidation. TAG-bound oxylipins may serve as better markers of lipid oxidation.

Linoleic acid (LA, 18:2n-6) is an essential nutrient for optimal infant growth and brain development. The effects of LA in the brain are thought to be mediated by oxygenated metabolites of LA known as oxidized LA metabolites (OXLAMs), but evidence is lacking to directly support this hypothesis. This study investigated whether OXLAMs modulate key neurodevelopmental processes including axon outgrowth, dendritic arborization, cell viability and synaptic connectivity. Primary cortical neuron-glia co-cultures from postnatal day 0-1 male and female rats were exposed for 48h to the following OXLAMs: 1) 13-hydroxyoctadecadienoic acid (13-HODE); 2) 9-hydroxyoctadecadienoic acid (9-HODE); 3) 9,10-dihydroxyoctadecenoic acid (9,10-DiHOME); 4) 12(13)-epoxyoctadecenoic acid (12(13)-EpOME); 5) 9,10,13-trihydroxyoctadecenoic acid (9,10,13-TriHOME); 6) 9-oxo-octadecadienoic acid (9-OxoODE); and 7) 12,13-dihydroxyoctadecenoic acid (12,13-DiHOME). Axonal outgrowth, evaluated by Tau-1 immunostaining, was increased by 9-HODE, but decreased by 12,13-DiHOME in male but not female neurons. Dendrite arborization, evaluated by MAP2B-eGFP expression, was affected by 9-HODE, 9-OxoODE, and 12(13)-EpOME in male neurons and, by 12(13)-EpOME in female neurons. Neither cell viability nor synaptic connectivity were significantly altered by OXLAMs. Overall, this study shows select OXLAMs modulate neuron morphology in a sex-dependent manner, with male neurons being more susceptible.

Maternal obesity during pregnancy is associated with neurodevelopmental disorder (NDD) risk. We utilized integrative multi-omics to examine maternal obesity effects on offspring neurodevelopment in rhesus macaques by comparison to lean controls and two interventions. Differentially methylated regions (DMRs) from longitudinal maternal blood-derived cell-free fetal DNA (cffDNA) significantly overlapped with DMRs from infant brain. The DMRs were enriched for neurodevelopmental functions, methylation-sensitive developmental transcription factor motifs, and human NDD DMRs identified from brain and placenta. Brain and cffDNA methylation levels from a large region overlappingmir-663correlated with maternal obesity, metabolic and immune markers, and infant behavior. ADUX4hippocampal co-methylation network correlated with maternal obesity, infant behavior, infant hippocampal lipidomic and metabolomic profiles, and maternal blood measurements ofDUX4cffDNA methylation, cytokines, and metabolites. We conclude that in this model, maternal obesity was associated with changes in the infant brain and behavior, and these differences were detectable in pregnancy through integrative analyses of cffDNA methylation with immune and metabolic factors.

Maternal gestational obesity is associated with elevated risks for neurodevelopmental disorder, including autism spectrum disorder. However, the mechanisms by which maternal adiposity influences fetal developmental programming remain to be elucidated. We aimed to understand the impact of maternal obesity on the metabolism of both pregnant mothers and their offspring, as well as on metabolic, brain, and behavioral development of offspring by utilizing metabolomics, protein, and behavioral assays in a non-human primate model. We found that maternal obesity was associated with elevated inflammation and significant alterations in metabolites of energy metabolism and one-carbon metabolism in maternal plasma and urine, as well as in the placenta. Infants that were born to obese mothers were significantly larger at birth compared to those that were born to lean mothers. Additionally, they exhibited significantly reduced novelty preference and significant alterations in their emotional response to stress situations. These changes coincided with differences in the phosphorylation of enzymes in the brain mTOR signaling pathway between infants that were born to obese and lean mothers and correlated with the concentration of maternal plasma betaine during pregnancy. In summary, gestational obesity significantly impacted the infant systemic and brain metabolome and adaptive behaviors.

Hormones are important signaling molecules controlling physiological homeostasis. ELISA kits are commonly used to measure hormones; however, few ELISA kits are multiplex, not all species-specific ELISA kits are commercially available, and ELISA kits typically require a significant volume of biological fluids. Pigs resemble humans in digestive physiology, making them an excellent model in preclinical research of nutrition and metabolism. In this study, we developed and validated a simple liquid–liquid extraction procedure and LC-MS/MS method for the simultaneous quantification of insulin, cortisol, glucagon-like peptide-1 (GLP-1) (7-37) and (7-36), acyl and des-acyl ghrelin, and carboxylated osteocalcin in pig serum. The proposed method is specific, highly sensitive (LOQ in ng/mL and pg/mL), reasonably accurate (more than 76.2% of all quality control samples within 20% error from nominal values), and precise (intra-day CV ≤ 10% and inter-day CV ≤ 23.1%). The recoveries of all analytes and corresponding internal standards ranged from 83.7 to 116.0%. The method also requires a low serum volume of 50–100 μL, which is invaluable when sample volume is limited. These methods could be easily extended for use in other mammalian species.