Background: Latino populations, especially those of Mexican ancestry, face higher rates of both cardiometabolic diseases and food insecurity, compounding negative health outcomes. Food insecurity is associated with poor dietary choices, which not only worsen cardiometabolic health but also contribute to various health complications, making it a critical public health issue in these communities. The aim of this study was to investigate the prevalence of food insecurity and its associations with diet, cardiometabolic risk factors, and glycemic control among Latino individuals of Mexican ancestry.
View Article and Find Full Text PDFContext: Humans with obesity and insulin resistance exhibit lipid accumulation in skeletal muscle, but the underlying biological mechanisms responsible for the accumulation of lipid in the muscle of these individuals remain unknown.
Objective: We investigated how plasma insulin modulates the extraction of circulating triglycerides (TGs) and non-esterified fatty acids (NEFAs) from ingested and endogenous origin in the muscle of lean, insulin-sensitive humans (Lean-IS) and contrasted these responses to those in humans with obesity and insulin resistance (Obese-IR).
Methods: The studies were performed in a postprandial state associated with steady-state plasma TG concentrations.
Context: Humans with obesity and insulin resistance exhibit lipid accumulation in skeletal muscle, but the underlying biological mechanisms responsible for the accumulation of lipid in the muscle of these individuals remain unknown.
Objective: We investigated how plasma insulin modulates the extraction of circulating triglycerides (TGs) and non-esterified fatty acids (NEFAs) from ingested and endogenous origin in the muscle of lean, insulin-sensitive humans (Lean-IS) and contrasted these responses to those in humans with obesity and insulin resistance (Obese-IR).
Methods: The studies were performed in a postprandial state associated with steady-state plasma TG concentrations.
Background: The COVID-19 pandemic caused societal disruption in the United States and most of the world, affecting many aspects of life, including healthcare and health-related behaviors such as diet, food security, and physical activity. Communities with economic and health disparities may have been particularly affected. This study was undertaken to determine how conditions in the early pandemic (January, 2021-February, 2022) affected Latino patients of Mexican Ancestry at high risk of type 2 diabetes mellitus who participated in El Banco por Salud biobank project in Tucson, Arizona.
View Article and Find Full Text PDFMany investigators have attempted to define the molecular nature of changes responsible for insulin resistance in muscle, but a molecular approach may not consider the overall physiological context of muscle. Because the energetic state of ATP (ΔG) could affect the rate of insulin-stimulated, energy-consuming processes, the present study was undertaken to determine whether the thermodynamic state of skeletal muscle can partially explain insulin sensitivity and fuel selection independently of molecular changes. P-MRS was used with glucose clamps, exercise studies, muscle biopsies and proteomics to measure insulin sensitivity, thermodynamic variables, mitochondrial protein content, and aerobic capacity in 16 volunteers.
View Article and Find Full Text PDFUnderstanding the mechanisms causing Parkinson's disease (PD) is vital to the development of much needed early diagnostics and therapeutics for this debilitating condition. Here, we report cellular and molecular alterations in skin fibroblasts of late-onset sporadic PD subjects, that were recapitulated in matched induced pluripotent stem cell (iPSC)-derived midbrain dopamine (DA) neurons, reprogrammed from the same fibroblasts. Specific changes in growth, morphology, reactive oxygen species levels, mitochondrial function, and autophagy, were seen in both the PD fibroblasts and DA neurons, as compared to their respective controls.
View Article and Find Full Text PDFThe vitamin D receptor (VDR) is vital for maintaining calcium and phosphate balance and regulating bone metabolism. Recent research has suggested that VDR also plays an essential role in metabolic diseases. Previous studies on non-Hispanic whites have shown that VDR single nucleotide polymorphisms (SNP) are associated with cardiometabolic phenotypes.
View Article and Find Full Text PDFUnderstanding the mechanisms causing Parkinson's disease (PD) is vital to the development of much needed early diagnostics and therapeutics for this debilitating condition. Here, we report cellular and molecular alterations in skin fibroblasts of late-onset sporadic PD subjects, that were recapitulated in matched induced pluripotent stem cell (iPSC)-derived midbrain dopamine (DA) neurons, reprogrammed from the same fibroblasts. Specific changes in growth, morphology, reactive oxygen species levels, mitochondrial function, and autophagy, were seen in both the PD fibroblasts and DA neurons, as compared to their respective controls.
View Article and Find Full Text PDFChronic inflammation is a major contributor to the development of obesity-induced insulin resistance, which then can lead to the development of type 2 diabetes (T2D). Skeletal muscle plays a pivotal role in insulin-stimulated whole-body glucose disposal. Therefore, dysregulation of glucose metabolism by inflammation in skeletal muscle can adversely affect skeletal muscle insulin sensitivity and contribute to the pathogenesis of T2D.
View Article and Find Full Text PDFResting skeletal muscle in insulin resistance prefers to oxidize carbohydrate rather than lipid, exhibiting metabolic inflexibility. Although this is established in resting muscle, complexities involved in directly measuring fuel oxidation using indirect calorimetry across a muscle bed have limited studies of this phenomenon in working skeletal muscle. During mild exercise and at rest, whole-body indirect calorimetry imperfectly estimates muscle fuel oxidation.
View Article and Find Full Text PDFIntroduction: Body mass index (BMI) percentile or BMI adjusted for age and sex is the most common anthropometric index to monitor and assess obesity in children. However, the ability of BMI to accurately predict insulin resistance (IR) in youth is debated. Determining the best method to noninvasively measure IR in the pediatric population is especially important due to the growing prevalence of type 2 diabetes mellitus (T2DM), which is more likely to develop in people with IR.
View Article and Find Full Text PDFHealth literacy (HL) is associated with short- and long-term health outcomes, and this is particularly relevant in Hispanics, who are disproportionally affected by lower HL. Hispanics have become the largest minority population in the United States. Also, Hispanics experience higher burdens of chronic diseases such as type 2 diabetes mellitus (T2DM) than non-Hispanic whites.
View Article and Find Full Text PDFAdherence to dietary and physical activity recommendations has been associated with reductions in morbidity and mortality. The association between baseline adherence to fruit, vegetable, and physical activity guidelines and metabolic syndrome (MetS) in El Banco por Salud (El Banco) was examined. El Banco is a wellness biobank for Latino individuals affiliated with partnered Federally Qualified Health Centers in southern Arizona.
View Article and Find Full Text PDFUnderserved Latino communities experience a greater burden of type 2 diabetes mellitus (T2DM) than the general population. Predictors of glycemic control are likely to include both biological/genetic and social determinants of health (SDOH). A variety of approaches have been used with cohorts of Latino patients to study aspects of this health disparity, and those are reviewed briefly here.
View Article and Find Full Text PDFSkeletal muscle is highly plastic and dynamically regulated by the body's physical demands. This study aimed to determine the plasticity of skeletal muscle DNA methylation in response to 8 weeks of supervised exercise training in volunteers with a range of insulin sensitivities. We studied 13 sedentary participants and performed euglycemic hyperinsulinemic clamps with basal vastus lateralis muscle biopsies and peak aerobic activity (VO2 peak) tests before and after training.
View Article and Find Full Text PDFThe ectodysplasin receptor (EDAR) is a tumor necrosis factor receptor (TNF) superfamily member. A substitution in an exon of EDAR at position 370 (EDARV370A) creates a gain of function mutant present at high frequencies in Asian and Indigenous American populations but absent in others. Its frequency is intermediate in populations of Mexican ancestry.
View Article and Find Full Text PDFEvidence suggests acetylation of human adenine nucleotide translocase 1 (ANT1) at lysine 23 (Lys23) reduces binding of ADP. Lys23 contributes to the positive charge that facilitates this interaction. This study was undertaken to characterize ANT1 abundance and acetylation by a novel method using small amounts of human skeletal muscle biopsies.
View Article and Find Full Text PDFLong chain polyunsaturated fatty acids (LC-PUFAs) have critical signaling roles that regulate dyslipidemia and inflammation. Genetic variation in the FADS gene cluster accounts for a large portion of interindividual differences in circulating and tissue levels of LC-PUFAs, with the genotypes most strongly predictive of low LC-PUFA levels at strikingly higher frequencies in Amerind ancestry populations. In this study, we examined relationships between genetic ancestry and FADS variation in 1102 Hispanic American participants from the Multi-Ethnic Study of Atherosclerosis.
View Article and Find Full Text PDFBackground: The mechanisms of weight loss and metabolic improvements following bariatric surgery in skeletal muscle are not well known; however, epigenetic modifications are likely to contribute. The aim of our study was to investigate skeletal muscle DNA methylation after weight loss induced by Roux-en-Y gastric bypass (RYGB) surgery. Muscle biopsies were obtained basally from seven insulin-resistant obese (BMI > 40 kg/m) female subjects (45.
View Article and Find Full Text PDFPurpose: Insulin resistant muscle is resistant to gene expression changes induced by acute exercise. This study was undertaken to identify transcription factors that differentially respond to exercise in insulin resistance. Candidate transcription factors were identified from analysis of 5'-untranslated regions (5'-UTRs) of exercise responsive genes and from analysis of the 5'-UTRs of genes coding for proteins that differ in abundance in insulin resistance.
View Article and Find Full Text PDFThe KADP of oxidative phosphorylation (OxPhos) identifies the cytosolic ADP concentration which elicits one-half the maximum OxPhos rate. This kinetic parameter is commonly measured to assess mitochondrial metabolic control sensitivity. Here we describe a luciferase-based assay to evaluate the ADP kinetic parameters of mitochondrial ATP production from OxPhos, adenylate kinase (AK), and creatine kinase (CK).
View Article and Find Full Text PDFVWA8 (Von Willebrand A Domain Containing Protein 8) is a AAA+ ATPase that is localized to the mitochondrial matrix and is widely expressed in highly energetic tissues. Originally found to be higher in abundance in livers of mice fed a high fat diet, deletion of the VWA8 gene in differentiated mouse AML12 hepatocytes unexpectedly produced a phenotype of higher mitochondrial and nonmitochondrial oxidative metabolism, higher ROS (reactive oxygen species) production mainly from NADPH oxidases, and increased HNF4a expression. The purposes of this study were first, to determine whether higher mitochondrial oxidative capacity in VWA8 null hepatocytes is the product of higher capacity in all aspects of the electron transport chain and oxidative phosphorylation, and second, the density of cristae in mitochondria and mitochondrial content was measured to determine if higher mitochondrial oxidative capacity is accompanied by greater cristae area and mitochondrial abundance.
View Article and Find Full Text PDFArterioscler Thromb Vasc Biol
February 2021
Objective: NFU1 is a mitochondrial iron-sulfur scaffold protein, involved in iron-sulfur assembly and transfer to complex II and LAS (lipoic acid synthase). Patients with the point mutation NFU1 and CRISPR/CAS9 (clustered regularly interspaced short palindromic repeats/clustered regularly interspaced short palindromic repeat-associated 9)-generated rats develop mitochondrial dysfunction leading to pulmonary arterial hypertension. However, the mechanistic understanding of pulmonary vascular proliferation due to a single mutation in NFU1 remains unresolved.
View Article and Find Full Text PDFPurpose: This report describes the return of sequencing results to low-income Latino participants recruited through a Federally Qualified Health Center (FQHC). We describe challenges in returning research results secondary to social determinants of health and present lessons learned to guide future genomic medicine implementation studies in low-resource settings.
Methods: Five hundred Latino adults (76% women) consented to research sequencing for a predetermined panel of actionable genes.