Per- and polyfluoroalkyl substances (PFAS) are ubiquitous endocrine-disrupting pollutants that cross the placenta and affect offspring health, but the extent and timing of their transfer to placental and fetal compartments remain poorly understood. We characterized the relationship between trimester-specific prenatal maternal serum PFAS levels and paired placental and cord plasma levels at term. Data came from the Central Arkansas Glowing prospective cohort (n=151, 2010-2014). Four well-detected PFAS were measured using liquid chromatography-tandem mass spectrometry. Regression, elastic net, and parametric g-formula models tested the association between maternal levels in each trimester and placental or cord PFAS levels. In g-formula models, trimester one (T1) or trimester two (T2) measures consistently had the largest effect sizes associated with placental levels (p<0.001-0.05). Similarly, T1 (PFHxS, PFNA, PFOS, PFOA), T2 (PFNA, PFOS, PFOA), and placental PFOA were associated with cord plasma levels (p<0.05-p<0.001). Results were robust to time-varying adjustment for estimated glomerular filtration rate, serum albumin, or maternal weight. Predictive models improved with additional timepoint measures. Our findings suggest PFOA may transfer more efficiently from the placenta to cord plasma and early-to-mid gestation maternal serum PFAS measures may serve as the most robust sentinels of fetoplacental exposure burden, suggesting early exposure prevention should be prioritized.

Ferroptosis is a form of cell death due to iron-induced lipid peroxidation. Ferroptosis suppressor protein 1 (FSP1) protects against this death by generating antioxidants, which requires nicotinamide adenine dinucleotide, reduced form (NADH) as a cofactor. We initially uncover that NADH exists at significant levels on cellular membranes and then find that this form of NADH is generated by aldehyde dehydrogenase 7A1 (ALDH7A1) to support FSP1 activity. ALDH7A1 activity also acts directly to decrease lipid peroxidation by consuming reactive aldehydes. Furthermore, ALDH7A1 promotes the membrane recruitment of FSP1, which is instigated by ferroptotic stress activating AMP-activated protein kinase (AMPK) to promote the membrane localization of ALDH7A1 that stabilizes FSP1 on membranes. These findings advance a fundamental understanding of NADH by revealing a previously unappreciated pool on cellular membranes, with the elucidation of its function providing a major understanding of how FSP1 acts and how an aldehyde dehydrogenase protects against ferroptosis.

Venipuncture of the upper extremities is commonly used to collect blood for plasma lipidomics. However, self-administered blood collection devices such as the Tasso+™ system for capillary blood sampling and plasma separation are convenient and enable frequent sampling without a clinical blood draw. The purpose of this study is to validate Tasso+ sampling for plasma lipidomics by comparing the venous blood and Tasso+-sampled capillary blood plasma lipidomes. Lipids are proven or putative biomarkers of human health and disease and indicators of nutritional and toxicological status. Because exchange of blood components including lipids occurs in capillaries, the capillary and venous blood lipidomes might be different, which could confound use of Tasso+-sampled blood as a surrogate for venous blood plasma. Here we compared the lipidomes of Tasso+-drawn capillary blood plasma and venous blood plasma in 10 male subjects using high-resolution mass spectrometry-based lipidomics. While there was substantial interindividual variability between lipidomes, comprehensive statistical approaches with cross-validation and multiple testing adjustments showed no difference (adjusted P-value > 0.05) in lipid composition of the paired blood samples. A linear regression model with Spearman correlation analysis also showed a significant-to-near-perfect level (r = 0.95-0.99) of concordance between the samples. Aside from monoacylglycerols and cardiolipins, every class of lipid was strongly correlated (r = 0.9-0.99) between paired venous and capillary blood plasma. In summary, the capillary and venous blood plasma lipidomes are essentially identical making self-administered collection of capillary blood a viable approach for clinical blood plasma lipidomics.

Per- and polyfluoroalkyl substances (PFAS) are endocrine-disrupting chemicals and widespread environmental contaminants. PFAS cross the placental barrier and reach the developing fetus with potential impacts on many organ systems. There are no studies of PFAS in residents of central Arkansas despite reports of environmental contamination in the region. We aimed to quantify PFAS concentrations in repeated serum samples from participants living in central Arkansas and to investigate relationships with maternal cardiometabolic health during pregnancy. Participants were enrolled during early pregnancy in a longitudinal study (NCT01131117) from 2010 to 2014. PFAS concentrations were measured in serum from each trimester (first trimester n = 282, second trimester n = 217, and third trimester n = 195). PFAS were compared across pregnancy. Linear and linear-mixed effects models were used to investigate relationships between trimester-specific PFAS levels, as single exposures, and maternal outcomes. Effects of PFAS as an exposure mixture were estimated using quantile g-computation. Six PFAS were detected in more than 70

Intracellular transport among organellar compartments occurs in two general ways: by membrane-bound carriers and membrane contacts. Specific circumstances that involve the coordination of these two modes of transport remain to be defined. By studying coat protein I (COPI) transport, we find that phosphatidylcholine with short acyl chains (sPC) is delivered through membrane contact from the endoplasmic reticulum (ER) to sites of COPI vesicle formation at the Golgi to support the fission stage. Phosphatidylinositol transfer protein beta (PITPβ) plays a key role in this process, with the elucidation of this role shedding new insights into how PITPβ acts, providing a mechanistic understanding of a specific circumstance when vesicular transport requires membrane contact and contributing to the general understanding of how intracellular transport carriers are formed.

Streptococcus mutans, the causative agent of human dental caries, expresses a cell wall attached Serotype c- specific Carbohydrate (SCC) that is critical for cell viability. SCC consists of a repeating →3)α-Rha(1→2)α-Rha(1→ polyrhamnose backbone, with glucose (Glc) side-chains and glycerol phosphate (GroP) decorations. This study reveals that SCC has one major and two minor Glc modifications. The major Glc modification, α-Glc, attached to position 2 of 3-rhamnose, is installed by SccN and SccM glycosyltransferases and is the site of the GroP addition. The minor Glc modifications are β-Glc linked to position 4 of 3-rhamnose installed by SccP and SccQ glycosyltransferases, and α-Glc attached to position 4 of 2-rhamnose installed by SccN working in tandem with an unknown enzyme. Both the major and the minor β-Glc modifications control bacterial morphology, but only the GroP and major Glc modifications are critical for biofilm formation.

Maternal serum per- and polyfluoroalkyl substances (PFAS) are linked to infant neurodevelopment vulnerabilities. However, the impact of placental PFAS exposure, a more proximal in utero exposure estimate, remains unknown. We hypothesize that elevated placental PFAS levels are associated with delayed neurodevelopment at 12 and 24 months.Mother-infant dyads (n = 151) were enrolled in a prospective cohort in Arkansas, US. PFOA, PFOS, PFHxS, PFNA, and PFDA were detected in >65 % of placentas. The Bayley Scales of Infant and Toddler Development (BSID)-III was administered at 12 and 24 months. Individual associations of each placental PFAS on BSID-III scores were examined using linear regressions. Mixture effects were assessed using quantile g-computation and Bayesian Kernel Machine Regression.Placental PFAS were jointly associated with lower cognitive (Ψ = -2.6; 95 % CI = -6.0, 0.9) and motor (Ψ = -2.9; 95 % CI = -6.6, 0.9) scores at 12 months and higher social-emotional scores (Ψ = 3.3; 95 % CI = -1.9, 8.5) at 24 months among males. Among females, higher PFAS mixture levels were associated with higher language (Ψ = 3.3; 95 % CI = -1.2, 7.7) and social-emotional (Ψ = 3.7; 95 % CI = -3.3, 10.6) scores at 24 months. Linear regressions showed PFHxS and PFOS were associated with lower cognitive scores at 12 months and PFDA was associated with lower motor scores at 12 months among males, while PFOS and PFNA were associated with higher social-emotional scores at 24 months among females, although confidence intervals included the null. In a matched subset with maternal serum, cord serum and placental PFAS (n = 98), we observed mostly null associations consistently across biomatrices and noted few associations, such as a negative relation of cord PFOA and PFHxS with language scores at 12 months among females.Overall, placental PFAS levels were modestly associated with performance on neurodevelopmental assessments in early childhood and these relationships were sex- and compound-specific, and most confidence intervals cross the null.

We have previously demonstrated that the glucocorticoid receptor β (GRβ) isoform induces hepatic steatosis in mice fed a normal chow diet. The GRβ isoform inhibits the glucocorticoid-binding isoform GRα, reducing responsiveness and inducing glucocorticoid resistance. We hypothesized that GRβ regulates lipids that cause metabolic dysfunction. To determine the effect of GRβ on hepatic lipid classes and molecular species, we overexpressed GRβ (GRβ-Ad) and vector (Vec-Ad) using adenovirus delivery, as we previously described. We fed the mice a normal chow diet for 5 days and harvested the livers. We utilized liquid chromatography-mass spectrometry (LC-MS) analyses of the livers to determine the lipid species driven by GRβ. The most significant changes in the lipidome were monoacylglycerides and cholesterol esters. There was also increased gene expression in the GRβ-Ad mice for lipogenesis, eicosanoid synthesis, and inflammatory pathways. These indicate that GRβ-induced glucocorticoid resistance may drive hepatic fat accumulation, providing new therapeutic advantages.

Sarcopenia burdens the older population through loss of muscle energy and mass, yet treatments to functionally rescue both parameters are lacking. The glucocorticoid prednisone remodels muscle metabolism on the basis of frequency of intake, but its mechanisms in sarcopenia are unknown. We found that once-weekly intermittent prednisone administration rescued muscle quality in aged 24-month-old mice to a level comparable to that seen in young 4-month-old mice. We discovered an activated receptor gamma coactivator 1 alpha (PGC1 alpha) and its cofactor Lipin1. Treatment coordinately improved mitochondrial abundance through isoform 1 and muscle mass through isoform 4 of the myocyte-specific PGC1 alpha, which was required for the treatmentdriven increase in carbon shuttling from glucose oxidation to amino acid biogenesis. We also probed myocyte-specific Lipin1 as a nonredundant factor coaxing PGC1 alpha upregulation to the stimulation of both oxidative and anabolic effects. Our study unveils an aging-resistant druggable program in myocytes for the coordinated rescue of energy and mass in sarcopenia.

Background and aims: Obesity and type 2 diabetes are significant risk factors for atherosclerotic cardiovascular disease (CVD) worldwide, but the underlying pathophysiological links are poorly understood. Neurotensin (NT), a 13-amino-acid hormone peptide, facilitates intestinal fat absorption and contributes to obesity in mice fed a high -fat diet. Elevated levels of pro-NT (a stable NT precursor produced in equimolar amounts relative to NT) are associated with obesity, type 2 diabetes, and CVD in humans. Whether NT is a causative factor in CVD is unknown. Methods: Nt + / + and Nt -/ - mice were either injected with adeno-associated virus encoding PCSK9 mutants or crossed with Ldlr -/ - mice and fed a Western diet. Atherosclerotic plaques were analyzed by en face analysis, Oil Red O and CD68 staining. In humans, we evaluated the association between baseline pro-NT and growth of carotid bulb thickness after 16.4 years. Lipidomic profiles were analyzed. Results: Atherosclerotic plaque formation is attenuated in Nt -deficient mice through mechanisms that are independent of reductions in circulating cholesterol and triglycerides but associated with remodeling of the plasma triglyceride pool. An increasing plasma concentration of pro-NT predicts atherosclerotic events in coronary and cerebral arteries independent of all major traditional risk factors, indicating a strong link between NT and atherosclerosis. This plasma lipid profile analysis confirms the association of pro-NT with remodeling of the plasma triglyceride pool in atherosclerotic events. Conclusions: Our findings are the first to directly link NT to increased atherosclerosis and indicate the potential role for NT in preventive and therapeutic strategies for CVD.

The global prevalence of obesity and its related comorbidities, including diabetes and metabolic dysfunction associated fatty liver disease (MAFLD), are on the rise. For unknown reasons, serum bilirubin levels are negatively correlated with obesity, diabetes, and MAFLD. We have previously generated pegylated bilirubin nanoparticles (PEGBR) and found they have therapeutic potential in preclinical models of diet-induced obesity and MAFLD. Bilirubin has long been known to function as an antioxidant. However, our lab has previously identified its hormonal function by binding to and activating the nuclear receptor peroxisome proliferator-activated receptor alpha (PPARa). It is unknown whether the beneficial effects of PEGBR are due to its antioxidant or hormonal function. To determine this, we induced obesity and MAFLD in female and male hepatocyte-specific PPARa knockout mice (PparaHepKO) and floxed (Pparaflox) control mice by a high-fat diet for 30 weeks. The mice were then treated with vehicle or PEGBR (30 mg/kg) for six weeks while remaining on the high-fat diet. In female Pparaflox mice, PEGBR significantly lowered body weight, but not in the female PparaHepKOmice. A similar trend was seen in the male Pparaflox mice but was not statistically significant. We found that PEGBR significantly reduced hepatic fat mass and triglycerides in the Pparaflox mice but not in the PparaHepKO mice in both sexes. We then performed mass-spectroscopy to analyze the hepatic lipid composition. In the male mice there was an 93.6% reduction in the number of lipid species that were significantly lowered by PEGBR in the PparaHepKO mice compared to the Pparaflox mice. While in the female PparaHepKO mice, there was a 2.7% reduction in the number of lipid species significantly decreased by PEGBR compared to Pparaflox controls. Plasma lipids and metabolites were quantified using NMR and we found that male Pparaflox mice had an increase in plasma high-density lipoprotein cholesterol and a decrease in very-low-density particle number with PEGBR, but this was not seen in the male PparaHepKO or female mice. PEGBR also significantly reduced fasting blood glucose and insulin levels only in the Pparaflox mice of both female and male mice. Overall, the data indicates bilirubin's hormonal function through PPARa is responsible for the protective effects of bilirubin on obesity, MAFLD, and glucose tolerance. This study also confirms the therapeutic potential of bilirubin nanoparticles for obesity and its associated comorbidities. This work was supported by the National Institutes of Health F31HL170972 (Z.A.K.) and R01DK121797 (T.D.H.J.) and R01DA058933 (T.D.H.J.).

Sarcopenia burdens the older population through loss of muscle energy and mass, yet treatments to functionally rescue both parameters are lacking. The glucocorticoid prednisone remodels muscle metabolism on the basis of frequency of intake, but its mechanisms in sarcopenia are unknown. We found that once-weekly intermittent prednisone administration rescued muscle quality in aged 24-month-old mice to a level comparable to that seen in young 4-month-old mice. We discovered an age- and sex-independent glucocorticoid receptor transactivation program in muscle encompassing peroxisome proliferator-activated receptor γ coactivator 1 α (PGC1α) and its cofactor Lipin1. Treatment coordinately improved mitochondrial abundance through isoform 1 and muscle mass through isoform 4 of the myocyte-specific PGC1α, which was required for the treatment-driven increase in carbon shuttling from glucose oxidation to amino acid biogenesis. We also probed myocyte-specific Lipin1 as a nonredundant factor coaxing PGC1α upregulation to the stimulation of both oxidative and anabolic effects. Our study unveils an aging-resistant druggable program in myocytes for the coordinated rescue of energy and mass in sarcopenia.

Ceramides are important intermediates in sphingolipid metabolism and serve as signaling molecules with independent biological significance. Elevated cellular and circulating ceramide levels are consistently associated with pathological conditions including cardiometabolic diseases, neurological diseases, autoimmune diseases, and cancers. Although pharmacological inhibition of ceramide formation often protects against these diseases in animal models, pharmacological modulation of ceramides in humans remains impractical. Dietary interventions including the Mediterranean diet, lacto-ovo-vegetarian diet, calorie-restricted diet, restriction of dairy product consumption, and dietary supplementation with polyunsaturated fatty acids, dietary fibers, and polyphenols, all have beneficial effects on modulating ceramide levels. Mechanistic insights into these interventions are discussed. This article reviews the relationships between ceramides and disease pathogenesis, with a focus on dietary intervention as a viable strategy for lowering the concentration of circulating ceramides.

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Supplemental Figure 2. Inhibition of FASN and sphingolipid metabolism limits formation of focal adhesion complexes in primary CRC cells.

Supplemental Figure 1. Expression of FASN, SPHK1 and SPHK2 in CRC.