Association Between Nutrition, Diet Quality, Dietary Patterns, and Human Health and Diseases.

Establishing relationships between diet and human health is an active and critical area of research, and this Special Issue, "Association Between Nutrition, Diet Quality, Dietary Patterns, and Human Health and Diseases", is a collection of research highlighting classic and emerging themes in this area [...

Sex-Specific Variation in Metabolic Responses to Diet.

Suboptimal nutrition is a leading cause of cardiometabolic disease and mortality. Biological sex is a variable that influences individual responses to dietary components and may modulate the impact of diet on metabolic health and disease risk. This review describes findings of studies reporting how biological sex may associate with or affect metabolic outcomes or disease risk in response to varying dietary macronutrient content, Mediterranean diet, Western diet, and medical very low-calorie diet.

Overexpression of manganese superoxide dismutase mitigates ACL injury-induced muscle atrophy, weakness and oxidative damage.

Oxidative stress has been implicated in the etiology of skeletal muscle weakness following joint injury. We investigated longitudinal patient muscle samples following knee injury (anterior cruciate ligament tear). Following injury, transcriptomic analysis revealed downregulation of mitochondrial metabolism-related gene networks, which were supported by reduced mitochondrial respiratory flux rates.

GDF8 inhibition enhances musculoskeletal recovery and mitigates posttraumatic osteoarthritis following joint injury.

Musculoskeletal disorders contribute substantially to worldwide disability. Anterior cruciate ligament (ACL) tears result in unresolved muscle weakness and posttraumatic osteoarthritis (PTOA). Growth differentiation factor 8 (GDF8) has been implicated in the pathogenesis of musculoskeletal degeneration following ACL injury.

Vitamin D status associates with skeletal muscle loss after anterior cruciate ligament reconstruction.

BACKGROUNDAlthough 25-hydroxyvitamin D [25(OH)D] concentrations of 30 ng/mL or higher are known to reduce injury risk and boost strength, the influence on anterior cruciate ligament reconstruction (ACLR) outcomes remains unexamined. This study aimed to define the vitamin D signaling response to ACLR, assess the relationship between vitamin D status and muscle fiber cross-sectional area (CSA) and bone density outcomes, and discover vitamin D receptor (VDR) targets after ACLR.METHODSTwenty-one young, healthy, physically active participants with recent ACL tears were enrolled (17.

Doubling down on best practices: reflecting on teaching physiology during the COVID-19 pandemic.

As we pass the third anniversary of the World Health Organization's declaration of the SARS-CoV-2 global pandemic, it is beneficial to reflect upon how physiology education adapted to the challenges of the pandemic. At the initial stages of the pandemic, many educators were faced with the challenge of quickly transitioning to emergency remote teaching (ERT), requiring shifts in teaching methodology and laboratory structure to adapt to the pandemic normal. In this review, we provide a broad overview of the efforts made by the community of educators associated with the American Physiological Society during the pandemic to encourage best practices in teaching, maintain course and program goals during ERT, and innovate in physiology education.

Secondary Organic Aerosol Mass Yields from NO Oxidation of α-Pinene and Δ-Carene: Effect of RO Radical Fate.

Dark chamber experiments were conducted to study the SOA formed from the oxidation of α-pinene and Δ-carene under different peroxy radical (RO) fate regimes: RO + NO, RO + RO, and RO + HO. SOA mass yields from α-pinene oxidation were <1 to ∼25% and strongly dependent on available OA mass up to ∼100 μg m. The strong yield dependence of α-pinene oxidation is driven by absorptive partitioning to OA and not by available surface area for condensation.

A Four Carbon Organonitrate as a Significant Product of Secondary Isoprene Chemistry.

Oxidation of isoprene by nitrate radicals (NO) or by hydroxyl radicals (OH) under high NO conditions forms a substantial amount of organonitrates (ONs). ONs impact NO concentrations and consequently ozone formation while also contributing to secondary organic aerosol. Here we show that the ONs with the chemical formula CHNO are a significant fraction of isoprene-derived ONs, based on chamber experiments and ambient measurements from different sites around the globe.

The T allele of TCF7L2 rs7903146 is associated with decreased glucose tolerance after bed rest in healthy older adults.

Inpatient populations are at increased risk of hyperglycemia due to factors such as medications, physical inactivity and underlying illness, which increases morbidity and mortality. Unfortunately, clinicians have limited tools available to prospectively identify those at greatest risk. We evaluated the ability of 10 common genetic variants associated with development of type 2 diabetes to predict impaired glucose metabolism.

Machine Learning-based Meal Detection Using Continuous Glucose Monitoring on Healthy Participants: An Objective Measure of Participant Compliance to Protocol.

Meal timing affects metabolic responses to diet, but participant compliance in time-restricted feeding and other diet studies is challenging to monitor and is a major concern for research rigor and reproducibility. To facilitate automated validation of participant self-reports of meal timing, the present study focuses on the creation of a meal detection algorithm using continuous glucose monitoring (CGM), physiological monitors and machine learning. While most CGM-related studies focus on participants who are diabetic, this study is the first to apply machine learning to meal detection using CGM in metabolically healthy adults.

Heterogeneous Nucleation Drives Particle Size Segregation in Sequential Ozone and Nitrate Radical Oxidation of Catechol.

Secondary organic aerosol formation via condensation of organic vapors onto existing aerosol transforms the chemical composition and size distribution of ambient aerosol, with implications for air quality and Earth's radiative balance. Gas-to-particle conversion is generally thought to occur on a continuum between equilibrium-driven partitioning of semivolatile molecules to the pre-existing mass size distribution and kinetic-driven condensation of low volatility molecules to the pre-existing surface area size distribution. However, we offer experimental evidence in contrast to this framework.

T1ρ imaging as a non-invasive assessment of collagen remodelling and organization in human skeletal muscle after ligamentous injury.

Dysregulation and fibrosis of the extracellular matrix (ECM) in skeletal muscle is a consequence of injury. Current ECM assessment necessitates muscle biopsies to evaluate alterations to the muscle ECM, which is often not practical in humans. The goal of this study was to evaluate the potential of a magnetic resonance imaging sequence that quantifies T1ρ relaxation time to predict ECM collagen composition and organization.

Vitamin D Promotes Skeletal Muscle Regeneration and Mitochondrial Health.

Vitamin D is an essential nutrient for the maintenance of skeletal muscle and bone health. The vitamin D receptor (VDR) is present in muscle, as is CYP27B1, the enzyme that hydroxylates 25(OH)D to its active form, 1,25(OH)D. Furthermore, mounting evidence suggests that vitamin D may play an important role during muscle damage and regeneration.

Gas-Particle Partitioning and SOA Yields of Organonitrate Products from NO-Initiated Oxidation of Isoprene under Varied Chemical Regimes.

Alkyl nitrate (AN) and secondary organic aerosol (SOA) from the reaction of nitrate radicals (NO) with isoprene were observed in the Simulation of Atmospheric PHotochemistry In a large Reaction (SAPHIR) chamber during the NOIsop campaign in August 2018. Based on 15 day-long experiments under various reaction conditions, we conclude that the reaction has a nominally unity molar AN yield (observed range 90 ± 40%) and an SOA mass yield of OA + organic nitrate aerosol of 13-15% (with ∼50 μg m inorganic seed aerosol and 2-5 μg m total organic aerosol). Isoprene (5-25 ppb) and oxidant (typically ∼100 ppb O and 5-25 ppb NO) concentrations and aerosol composition (inorganic and organic coating) were varied while remaining close to ambient conditions, producing similar AN and SOA yields under all regimes.

A Systematic Review of Bystander Interventions for the Prevention of Sexual Violence.

Introduction: Bystander interventions have been successful in changing bystander attitudes and behaviors to prevent sexual violence. This systematic review was performed to summarize and categorize the characteristics of sexual violence bystander intervention programs and analyze bystander intervention training approaches for the primary prevention of sexual violence and assault.

Method: From June to July 2017, the authors searched both published and unpublished American and Canadian studies from 2007 to 2017.

Coupling of organic and inorganic aerosol systems and the effect on gas-particle partitioning in the southeastern US.

Several models were used to describe the partitioning of ammonia, water, and organic compounds between the gas and particle phases for conditions in the southeastern US during summer 2013. Existing equilibrium models and frameworks were found to be sufficient, although additional improvements in terms of estimating pure-species vapor pressures are needed. Thermodynamic model predictions were consistent, to first order, with a molar ratio of ammonium to sulfate of approximately 1.

Alkoxy Radical Bond Scissions Explain the Anomalously Low Secondary Organic Aerosol and Organonitrate Yields From α-Pinene + NO.

Oxidation of monoterpenes (CH) by nitrate radicals (NO) constitutes an important source of atmospheric secondary organic aerosol (SOA) and organonitrates. However, knowledge of the mechanisms of their formation is incomplete and differences in yields between similar monoterpenes are poorly understood. In particular, yields of SOA and organonitrates from α-pinene + NO are low, while those from Δ-carene + NO are high.

Nitrate radicals and biogenic volatile organic compounds: oxidation, mechanisms, and organic aerosol.

Oxidation of biogenic volatile organic compounds (BVOC) by the nitrate radical (NO) represents one of the important interactions between anthropogenic emissions related to combustion and natural emissions from the biosphere. This interaction has been recognized for more than 3 decades, during which time a large body of research has emerged from laboratory, field, and modeling studies. NO-BVOC reactions influence air quality, climate and visibility through regional and global budgets for reactive nitrogen (particularly organic nitrates), ozone, and organic aerosol.

Vascular Smooth Muscle Sirtuin-1 Protects Against Diet-Induced Aortic Stiffness.

Arterial stiffness, a major cardiovascular risk factor, develops within 2 months in mice fed a high-fat, high-sucrose (HFHS) diet, serving as a model of human metabolic syndrome, and it is associated with activation of proinflammatory and oxidant pathways in vascular smooth muscle (VSM) cells. Sirtuin-1 (SirT1) is an NAD(+)-dependent deacetylase regulated by the cellular metabolic status. Our goal was to study the effects of VSM SirT1 on arterial stiffness in the context of diet-induced metabolic syndrome.

Vascular Smooth Muscle Sirtuin-1 Protects Against Aortic Dissection During Angiotensin II-Induced Hypertension.

Background: Sirtuin-1 (SirT1), a nicotinamide adenine dinucleotide(+)-dependent deacetylase, is a key enzyme in the cellular response to metabolic, inflammatory, and oxidative stresses; however, the role of endogenous SirT1 in the vasculature has not been fully elucidated. Our goal was to evaluate the role of vascular smooth muscle SirT1 in the physiological response of the aortic wall to angiotensin II, a potent hypertrophic, oxidant, and inflammatory stimulus.

Methods And Results: Mice lacking SirT1 in vascular smooth muscle (ie, smooth muscle SirT1 knockout) had drastically high mortality (70%) caused by aortic dissection after angiotensin II infusion (1 mg/kg per day) but not after an equipotent dose of norepinephrine, despite comparable blood pressure increases.

Secondary organic aerosol formation and organic nitrate yield from NO3 oxidation of biogenic hydrocarbons.

The secondary organic aerosol (SOA) mass yields from NO3 oxidation of a series of biogenic volatile organic compounds (BVOCs), consisting of five monoterpenes and one sesquiterpene (α-pinene, β-pinene, Δ-3-carene, limonene, sabinene, and β-caryophyllene), were investigated in a series of continuous flow experiments in a 10 m(3) indoor Teflon chamber. By making in situ measurements of the nitrate radical and employing a kinetics box model, we generate time-dependent yield curves as a function of reacted BVOC. SOA yields varied dramatically among the different BVOCs, from zero for α-pinene to 38-65% for Δ-3-carene and 86% for β-caryophyllene at mass loading of 10 μg m(-3), suggesting that model mechanisms that treat all NO3 + monoterpene reactions equally will lead to errors in predicted SOA depending on each location's mix of BVOC emissions.

A redox-resistant sirtuin-1 mutant protects against hepatic metabolic and oxidant stress.

Sirtuin-1 (SirT1), a member of the NAD(+)-dependent class III histone deacetylase family, is inactivated in vitro by oxidation of critical cysteine thiols. In a model of metabolic syndrome, SirT1 activation attenuated apoptosis of hepatocytes and improved liver function including lipid metabolism. We show in SirT1-overexpressing HepG2 cells that oxidants (nitrosocysteine and hydrogen peroxide) or metabolic stress (high palmitate and high glucose) inactivated SirT1 by reversible oxidative post-translational modifications (OPTMs) on three cysteines.