bluuebunny/crossref_metadata_2025_split huggingface dataset:
The NADPH‐Production Enzyme Isocitrate Dehydrogenase Maintains Quiescence in Hair Follicle Stem Cells
Authors: Ambrus Aaron Michael , Lemons Johanna , Raitman Irene , Krishnan Nithya , Jelinek David , Suh Eric , Remillard Matthew , Shilo Noya , Haley Erin , Sun Lova , Xiao Roy , Flores Aimee , Wang David , White Andrew , Lowry William , Coller Hilary 
Published: June 2021

NADPH is a critical metabolite that is important for regenerating reduced glutathione from oxidized glutathione and eliminating reactive oxygen species (ROS). Metabolic flux and microarray experiments in fibroblasts demonstrated that NADPH‐producing enzymes, glucose‐6‐phosphate dehydrogenase (G6PD), isocitrate dehydrogenase (IDH), and the upstream transcription factor NRF2, are all activated in quiescent compared with proliferating fibroblasts. We demonstrated that G6PD and NRF2 are functionally important for quiescence by showing that inhibition of G6PD or NRF2 results in oxidative stress and apoptosis specifically in quiescent fibroblasts. Flow cytometry experiments demonstrated that ROS in quiescent cells can be derived from mitochondrial superoxide that results from increased mitochondrial activity in the serum‐starved compared with proliferating fibroblasts, as well as an increase in reactive nitrogen species that arise from peroxisomes. To understand the physiological role of NADPH‐production pathways, we examined their potential activity in mouse skin. Consistent with our findings in quiescent fibroblasts, in situ metabolic activity assays revealed higher potential activity for G6PD and IDH in non‐dividing cells. Of particular interest was the high IDH potential in quiescent hair follicle stem cells. Staining of live mouse skin with monochlorobimane showed higher reactivity, consistent with higher levels of reduced glutathione, in hair follicle stem cells. Inhibition of IDH activity in healthy mouse skin with two different inhibitors resulted in progression in the hair follicle cycle from a quiescent to proliferative state suggesting that the high IDH activity observed in hair follicle stem cells may contribute to the maintenance of these stem cells in a quiescent state. Going forward, our focus is on understanding the role of IDH in the maintenance of stem cells as opposed to proliferating, committed progenitor cells.Support or Funding InformationH.A.C. was the Milton E. Cassel scholar of the Rita Allen Foundation. This work was supported by NIGMS Center of Excellence grant P50 GM071508, two grants from the Cancer Institute of New Jersey, the New Jersey Commission on Cancer Research, National Cancer Institute 1RC1 CA147961‐01, a Focused Funding Grant to H.A.C. from the Johnson & Johnson Foundation and a grant from the PhRMA Foundation to H.A.C, and XXXX to W.E.L. J.M.S. was supported by NIH training grant T32 HG003284. E.M.H. acknowledges a Bowen Fellowship from Princeton University and the New Jersey Commission on Cancer Research. E.J.S. acknowledges support from the National Science Foundation.
Subacute neuroendocrine and behavioral effects of underwater trauma and predator exposure in rats
Authors: Moore Nicole L.T. , Cravedi Kevin , Vuong Chau , Sousa Jason C , Marcsisin Sean R 
Published: June 2021

Traumatic stress physiological response and recovery encompasses a wide range of measurable behavioral and neuroendocrine changes in rats. Acute stress response and return to baseline may vary across differing neuroendocrine signaling molecules and behavioral manifestations, and may also be influenced by extrinsic factors such as the specific stressor presented or phase of the circadian cycle during which responses are evaluated. While rodent models of traumatic stress have been used to evaluate acute and chronic changes in these measures, few longitudinal studies have been done to characterize multiple interrelated neuroendocrine markers across the circadian cycle and compare to acute and lasting behavioral changes. We set out to describe the subacute effects of traumatic stress exposure on exploratory behavior, acoustic startle response, and a panel of neuroendocrine markers across the circadian cycle. Rats were exposed to either underwater trauma (UWT) or predator exposure (PRED). Then repeated behavioral tests (exploratory behavior on the elevated plus maze, acoustic startle) were conducted across 7 days, or in yoked cohorts, blood samples were collected at 10 time points over the next 7 days. Neuroendocrine markers were quantified from serum using LC‐MS or ELISA, analyzed over time, and compared against behavioral responses at several corresponding time points. Preliminary data show differential responses for UWT and PRED across the experimental timeline, and distinct response timelines for the different measures collected.Support or Funding InformationSupported by the Military Operational Medicine Research Program, US Army Medical Research and Materiel Command.
Genetic influence on xanthine oxidase activity and arginine metabolites in Hispanic children
Authors: Voruganti V. Saroja , Chittoor Geetha , Haack Karin , Laston Sandra , Vazquez‐Vidal Itzel , Mehta Nitesh R , Comuzzie Anthony G , Cole Shelley A , Butte Nancy F 
Published: June 2021

Xanthine oxidase (XO) catalyzes the oxidation of xanthine and hypoxanthine in the uric acid metabolic pathway generating reactive oxygen species in the process. Inhibition of XO activity is known to reduce oxidative damage and improve endothelial function. The aim of this study was to identify the genetic basis of estimated XO activity and its relationship with endothelial function biomarkers in 752 Hispanic children of the Viva La Familia Study. Xanthine, hypoxanthine and other biomarkers were measured as part of metabolomics profiling. Xanthine oxidase activity was estimated as a product/precursor ratio. Quantitative genetic analysis was conducted using a variance components decomposition‐based method accounting for kinships. Significant heritabilities were obtained for XO activity (h2 = 0.60 ±0.08; p = 1.6 × 10−14), homocysteine (h2 = 0.82± 0.07; p = 5.2 × 10−32) and arginine metabolites; arginine (h2 = 0.47± 0.09; p = 4.6 × 10−9) and dimethylarginine (h2 = 0.24 ± 0.08; p = 0.001). Significant genetic and phenotypic correlations were found between XO activity and homocysteine (rhog = −0.21 ± 0.10; p < 0.05; rhop = −0.15 ± 0.05; p < 0.0005), arginine (rhog = 0.39 ± 0.13; p < 0.005; rhop = 0.15 ± 0.05; p < 0.0005) and dimethylarginine (rhog = −0.60 ± 0.17; p < 0.0005; rhop = −0.13 ± 0.05; p < 0.001). Genome‐wide association analysis showed significant association of XO with rs7809463 in archaelysin family metallopeptidase1 (AMZ1) and rs58632700 in a gene encoding zinc finger protein 446 (ZNF446) (p < 10−8). Follow up bivariate analysis found significant evidence of pleiotropic effects of echinoderm microtubule associated protein like 6 (EML6) on XO activity and methylarginine (p < 10−8), and suggestive evidence of AMZ1 and ZNF446 on XO activity and arginine (p < 10−7). Interestingly, L‐Arginine is known to have a protective effect against reactive oxygen species and its supplementation is believed to reduce oxidative damage. The results show that shared genetic factors influence XO activity and arginine metabolites with opposing effects in Hispanic children with important implications for diseases such as obesity, diabetes and cardiovascular disease.Support or Funding InformationNational Institutes of Health (NIH) [DK080457], and the USDA/ARS [Cooperative Agreement6250‐51000‐053]
Comparison of Resuscitation Fluids in Maintaining Mitochondrial DNA Integrity in Human Endothelial Cells
Authors: Gibson Ruby S , Barr Johnny L , Dubick Michael A , Bowman Phillip D 
Published: June 2021

In our continuing evaluation of resuscitation fluids in the treatment of hemorrhage, the objective of this study was to determine if standard resuscitation fluids lead to increased damage to mitochondrial DNA (mtDNA) during periods of increasing oxidative stress as associated with shock states. Mitochondria are responsible for maintaining the cellular energy balance and are involved in the triggering of apoptosis in response to oxidative stress. The majority of mitochondrial proteins are encoded by nuclear DNA, however, mitochondria retain their own genome consisting of a circular duplex molecule of approximately 16.5 kb encoding 13 polypeptides that are exclusively involved in the intracellular ATP production by the electron transport chain (ETC). MtDNA, like the ETC, is localized at the inner side of the mitochondrial inner membrane. The ETC reduces oxygen to water in four consecutive one‐electron steps and reactive oxygen species (ROS) are produced as a by‐product of this process. These reactive molecules can be converted to H2O2 spontaneously or by superoxide dismutase resulting in free hydroxyl radicals (•OH) in the presence of iron via Fenton chemistry. ROS, in particular hydroxyl radicals, exhibit a high capacity to impair proteins, lipid membranes, DNA and RNA, which are essential components of functional mitochondria. Since, many of these resuscitation fluids lack substrates for mitochondrial production of ATP we proposed that they would enhance generation of ROS. Human umbilical vein endothelial cells (HUVEC) were treated for 3 hrs to 10 mM Hepes‐buffered Hank's solution, Ringer's solution, lactated Ringer's (LR), normal saline (NR), 5% albumin (5% Alb) and Hextend. The cells were fixed in 50% isopropanol and DNA extracted with DNAzol (MRC, Cincinnati, OH) and subjected to real‐time polymerase chain reaction (RT‐PCR) with primers designed to amplify large and small regions of mitochondrial and nuclear DNA where the extent of template amplification is inversely proportional to the lesion frequency within a given DNA sequence. Detected lesions per 10kb DNA were determined. Compared to hydrogen peroxide induced DNA damage, the tested resuscitation fluids did not produce significant alterations in the mtDNA or nuclear DNA. These data suggest that based on our previous observations of a lack on intrinsic antioxidant activity in these fluids, none would offer any advantage in influencing ROS production or mitochondrial dysfunction induced by a shock state.Support or Funding InformationThis study was funded by the US Army Medical Research and Materiel Command.
Reduced Fatty Acid Binding Capacity of Human Albumin Used in Volume Resuscitation May Potentially Increase Hemolysis in Hypovolemic Shock
Authors: Penn Alexander Hayes , Dubick Michael , Filho Ivo Torres 
Published: June 2021

The choice of resuscitation fluid for hypovolemic trauma patients in the absence of fresh whole blood remains controversial. Albumin solutions have shown promise in animal studies but meta‐analysis suggests they have had little to no benefit in human trials. This contradiction is currently unresolved. Unbound (cytotoxic) free fatty acids (FFAs) are generated in the intestine during ischemia and enter the mesenteric lymph, from where they likely enter the circulation, resulting in organ damage, hemolysis, coagulopathy and further ischemia. We hypothesize that resuscitation fluids with higher available binding capacities for FFAs may help prevent these events in shock. The objectives of this in‐vitro study were to determine: 1) if commercial sources of pharmaceutical‐grade human albumin contain FFAs, 2) if these FFAs result in a decreased available fatty acid binding capacity, and 3) if binding capacity will affect the level of hemolysis that occurs in whole blood when exogenous FFA is introduced in levels similar to those in shock. To achieve these objectives, we first measured FFA concentrations in human albumin via a kit. We then developed a new assay for measuring fatty acid binding capacity using exogenous oleic acid (OA), glass fiber filtration, and the FFA kit to measure binding capacity in both the human albumin and FFA‐free bovine albumin. Lastly, we mixed fresh human whole blood 4:1 with PBS, human albumin, FFA‐free bovine serum albumin (BSA), or BSA that was first saturated to its binding capacity with OA and measured the amount of hemoglobin released into the plasma after 30 minute incubation with 0 to 5 mM OA. We found that pharmaceutical‐grade 5% human albumin contained 4.6±0.3 mM FFA (N=5 lots), ~7x the physiologic concentration, leaving an available binding capacity of 4.8±0.6 mM out of a total binding capacity of 9.4±0.8 mM. This represented a significant loss of binding capacity (p<0.0001) compared to the total. FFA‐free BSA (N=5 replicates) had significantly greater available binding capacity of 7.0±1.4 mM (p=0.02) compared to the pharmaceutical‐grade human albumin. In 4:1 mixtures of blood to PBS or albumin, hemolysis was reduced after addition of all concentrations of exogenous OA with 25% FFA‐free compared to 25% pre‐saturated BSA (p<0.04). Likewise, 0.5 and 5 mM exogenous OA caused less hemolysis when blood was pre‐mixed with 5% FFA‐free BSA than with 5% human albumin (p<0.01). These preliminary findings suggest that the failure of albumin in human trials to live up to the promise of animal studies may be due to steps in the manufacturing process that reduce the FFA binding capacity of human albumin.Support or Funding InformationSupported by US Army Medical Research & Materiel Command.
Perinatal Exposure to Brominated Flame Retardants Reduces Social Recognition in Adult Male Mice Concomitant with Reduced Amygdalar Avp Expression
Authors: Valdez Matt , Gonzalez Gwen , Gutierrez Roberto , Valdez Joseph , Lindner John , McLaughlin Thu , Leon‐Olea Martha , Curras‐Collazo Margarita 
Published: June 2021

Polybrominated diphenyl ethers (PBDEs) are flame‐retardants associated with impaired cognitive and behavioral deficits in children. PBDEs are endocrine‐disrupting chemicals that also have neurotoxicological actions. In humans, PBDEs have been associated with disrupted attention, hyperactivity and lower IQ scores. This study evaluates behaviors relevant to autism spectrum disorder (ASD) and examines correlative changes in forebrain expression of genes after perinatal exposure to the industrial PBDE mixture, DE‐71. Genes for vasopressin (Avp) and oxytocin signaling (Oxtr) serve as markers for social circuits. Pituitary adenylate cyclase activating polypeptide, PACAP (Adcyap1r1), and its receptor, PAC1R (Adcyap1r1) are critical for neurodevelopment. Female C57BL/6 dams were dosed for 10 weeks (pre‐conception: 4 weeks; gestation: 3 weeks; lactation: 3 weeks). Dosing consisted of low dose (0.1 mg/kg/d), high dose (0.4 mg/kg/d), or corn oil vehicle (control) via ingestion of infused corn flakes. Exposed progeny were subjected to behavioral testing: Sociability (PND 21), Open Field (PND 30–40), Marble Burying (PND 40–50), Social Recognition (PND 55–60), and Elevated Plus Maze (PND 60–65). High dose DE‐71 treatment produced a sex‐independent decrease in repetitive behavior (F2,54=5.96, p<0.005). In males, high dose DE‐71 treatment produced hyperactivity (p<0.05). The social recognition test revealed significant preference for a novel conspecific in control males (F1,23=7.38, p<0.05) and females (F1,22=18.05, p<0.0005) but not in any DE‐71 groups. The latter could not be attributed to reduced sociability. Plasma showed reduced (p<0.05) and increased (p<0.05) plasma arginine‐vasopressin in low and high dose males, respectively. qPCR analysis revealed an apparent decrease in Avp gene expression in lateral septum and medial amygdala of low dose DE‐71 males compared to controls. In contrast, the supraoptic nucleus displayed significantly increased Avp expression in low dose DE‐71 mice (p=0.243). These mice also showed an apparent decrease in Oxtr, Adcyap1 and Adcyap1r1 expression in amygdala and in Adcyap1r1 in cingulate cortex compared to controls. Preliminary histological analysis has revealed a significant transient increase in cell density of the cingulate cortex at PND 7 (p=0.012) in high dose males compared to controls. By PND 71, the cell density of the cingulate cortex becomes significantly decreased (p<0.001) in high dose males compared to controls (n=2–3/group). We conclude that developmental PBDEs produce ASD‐relevant neurodevelopmental and behavioral abnormalities that maybe due, in part, to changes in vasopressinergic and PACAPergic circuits.Support or Funding InformationSupport: APS (G.G.), MARC (G.G., J.V, R.G.), UCMEXUS (M.C‐C., M.L‐O.), NSF (M.V.) and Sigma Xi (G.G., M.V.).
Changes in Protein Turnover, Hormonal Status, and Body Composition during Physiologically Demanding Military Training
Authors: Pasiakos Stefan M , Berryman Claire E , Margolis Lee M , Sepowitz John J , McClung Holly L , Lieberman Harris R , McClung James P , Ferrando Arny A 
Published: June 2021

Physiological stress imposed during short‐term military training is often severe and intentional; producing a catabolic state and loss of lean body mass (LBM). The extent to which this occurs and metabolic responses that may contribute to the loss of LBM are not well characterized. This study examined body composition, whole‐body protein turnover (15N‐alanine), testosterone and cortisol before (BASELINE) and after (POST) 7 days of Survival, Evasion, Resistance, and Escape (SERE) School in 68 male US Marines (mean ± SD, 25 ± 2 y, 83.7 ± 9.1 kg). Total body mass (TBM) was 7% lower (−2.7 ± 1.4 kg fat and −3.1 ± 1.7 kg LBM), proteolysis 28% higher and net protein balance 132% lower POST‐SERE (P < 0.05) compared to BASELINE. Decrements in testosterone POST‐SERE (−42%; −221 ± 136 ng/dL; P < 0.05) were inversely related with increased proteolysis (r = −0.30; P < 0.05) and protein synthesis (r = −0.28; P < 0.05). Percent changes in testosterone were associated with percent loss of TBM (r = 0.37; P < 0.05) and LBM (r = 0.31; P < 0.05). Cortisol changes during SERE were associated with changes in protein synthesis (r = 0.26; P < 0.05). Percent change in cortisol was inversely associated with percent change in fat mass (r = −0.34, P < 0.05) and tended to predict the percent change in LBM (r = 0.22; P = 0.07). The physiological stress during SERE elicits a hypogonadal state and catabolism of LBM. Decrements in testosterone were quantitatively associated with the increase in proteolysis and loss of LBM.Support or Funding InformationSupported by USAMRMC
Assessment of home food environment among healthy weight and overweight/obese school‐age children
Authors: Nepper Martha J , Chai Weiwen 
Published: June 2021

ObjectiveTo compare the differences in the availability and visibility of home healthy and unhealthy foods and family meal frequency and quality between healthy weight and overweight/obese children.MethodsForty‐two overweight/obese and 40 healthy weight children (9.8±2.6 years) and their parents participated in the study. In‐home assessment for food availability and visibility was conducted and children's weight and height were measured by researchers. Self‐report survey regarding demographics and family meals were completed by the parents. Logistic regression analysis was used to examine associations of demographic characteristics, home food availability and visibility and family meal variables with children's weight status.ResultsThe availability of home total unhealthy foods was significantly and inversely associated with overweight/obesity among children. The association was not significant after adjusting for single‐parent household and parent working status. Lower visibility of home total unhealthy foods (OR=0.60, 95% CI=0.39–0.92, P=0.02) and lower frequency of family meals (OR=0.10, 95% CI=0.01–0.96, P=0.02) were significantly associated with children being overweight/obese after adjustment for covariates. Parents who worked full‐time (OR=4.14, 95% CI=1.62–10.54, P=0.008), single parent household (OR=5.25, 95% CI=1.72–16.07, P=0.002), and older parents (OR=1.11, 95% CI=1.03–1.20, P=0.004) were positively associated with overweight/obesity of children.ConclusionHelping and educating parents to create a healthier home food environment is important for both overweight/obese and healthy weight children.Support or Funding InformationThis research was supported by the University of Nebraska‐Lincoln Research Council Faculty Seed grant and in part by Agriculture and Food Research Initiative (AFRI) Grant 2011‐67002‐30202 from the U.S. Department of Agriculture (USDA) National Institute of Food and Agriculture, Childhood Obesity Prevention: Transdisciplinary Graduate Education and Training in Nutrition and Family Sciences or Child Development or Related Fields to Prevent Childhood Obesity.
Heat Stress Causes Autophagic Stalling In Oxidative Skeletal Muscle
Authors: Brownstein Alexandra , Summers Corey , Ganesan Shanthi , Hale Benjamin , Pearce Sarah , Gabler Nicholas , Ross Jason W , Rhoads Robert P. , Baumgard Lance H. , Selsby Joshua T. 
Published: June 2021

Heat stress (HS) poses a threat to human and animal health and well being, and serves to undermine agricultural economics and food security. Yet, little is known about underlying pathological mechanisms caused by HS, which impedes the development of effective mitigation strategies. To address this critical need we have been working to elucidate HS‐mediated dysfunction in skeletal muscle and have implicated the mitochondria as likely contributors to cellular pathology. Given the possibility of mitochondrial dysfunction we hypothesized that cells would respond to HS by clearing damaged mitochondria via autophagy. To test this hypothesis gilts (female pigs; 35±4 kg; n=5–6/group) were housed in thermoneutral (TN; 20 ± 1°C) or HS (35°C) conditions for one (HS1) or three days (HS3). Relative protein abundance of markers of autophagosome membrane nucleation, Phosphatidylinositide 3‐kinases class III, Beclin‐1, elongation (Autophagy‐related protein 16L1), and maturation of autophagosomes (Microtubule‐associated protein A/B‐light chain 3 II) was increased (p<0.05) following 1 and 3 days of HS. Conversely, sequestosome‐1 (p62), a selective autophagy receptor consumed by autophagy and inversely associated with autophagy flux, was not detected in TN pigs, dramatically increased following 1 day of HS, and decreased by 3.4‐fold (but was still readily detectable) following 3 days of HS compared to 1 day of HS (p<0.05). Gene expression of p62 was similar between groups. In addition, mitophagy marker, BCL2/Adenovirus E1B 19kDa interacting protein 3‐like (Bnip3L) was decreased 2.5‐fold (p<0.05) after 1 and 3 days of HS and PTEN‐induced putative kinase 1 (PINK1) was decreased 7.0‐fold following 1 day of HS (p<0.05) and numerically by 2.4‐fold following 3 days of HS. Together, these data suggest that HS drives autophagy but this process stalls resulting in the accumulation of autophagosomes, suppressed mitophagy, and the preservation of dysfunctional mitochondriaSupport or Funding InformationSupported by USDA grants 2014‐67015‐21627 and 2011‐67003‐30007.