bluuebunny/crossref_metadata_2025_split huggingface dataset:
Alteration in skeletal muscle antioxidant defense gene expression profile following multiple exposures to hyperthermia
Authors: Sanders Sara , Flann Kyle L. , Yamazaki Marie , Baumgard Lance H. , Rhoads Robert P. 
Published: June 2021

Heat load is a potent stressor, due in part, to alterations in the production of reactive oxygen species (ROS). The ability of skeletal muscle to mitigate potentially harmful effects of hyperthermia and elevated ROS is unclear. Study objectives were to determine the effects of single and multiple bouts of acute heat stress (HS) on the expression of genes associated with antioxidant defense in soleus (type I; oxidative) and tibialis anterior (TA; type II; glycolytic) skeletal muscles. Male Sprague Dawley rats (n = 12; 9 mo) were randomly assigned to one of 3 treatment groups; thermoneutral (TN; 22°C) or either 1 or 2 exposures to HS conditions (40°C, 20% relative humidity, 6 h each). Rats were anesthetized and skeletal muscles were collected. Total RNA was isolated and cDNA generated for a real‐time PCR‐based array (SABiosciences). During TN, gene expression of antioxidants (catalase, glutathione peroxidases, peroxiredoxins, and superoxide dismutase 1) were greater (p < 0.05) in the soleus compared to TA. After one bout of heat, the difference in antioxidant gene expression observed during TN increased (p < 0.05) further between the soleus and TA. In contrast, differences in antioxidant gene expression between soleus and TA became less apparent following two HS bouts. Overall, this data indicates that HS alters expression of genes associated with antioxidant defense in a skeletal muscle type specific manner.This work was funded by the National Research Initiative Competitive Grant no. 2008‐35206‐18817 from the USDA Cooperative State Research, Education, and Extension Service.
Lipoprotein lipase (LPL) facilitates the uptake of postprandial vitamin A by the developing tissues
Authors: Wassef Lesley , Quadro Loredana 
Published: June 2021

Postprandial vitamin A, incorporated in chylomicrons as retinyl ester (RE), is an important source of retinoids for the developing embryo. Lipoprotein lipase (LPL) hydrolyses chylomicrons to smaller chylomicron remnants‐RE and facilitates the uptake of chylomicron remnants containing retinoids in extrahepatic tissues. Although, its expression has been reported in placenta, it is not clear whether LPL facilitates postprandial uptake of vitamin‐A by this tissue.In this study, RE levels in embryos from mice lacking placental LPL (MCKhLPL/LPL−/ −) are reduced both on a vitamin‐A sufficient or excess diet, despite a normal embryonic phenotype. Furthermore, when the dams are maintained on a vitamin A‐sufficient diet and their retinoid stores are adequate, pharmacological systemic inhibition of LPL activity, by means of the lipase inhibitor P‐407, impairs the uptake of chylomicrons RE in yolk sac and embryo, but not in placenta. In contrast, when maternal retinoid stores are depleted, pharmacological systemic inhibition of LPL does not impair neither embryonic nor extraembryonic uptake of RE. These results suggest that LPL facilitates the uptake of postprandial vitamin A by the developing tissues, but it is not the only player that ensures availability of dietary vitamin‐A to the embryo.Research support: NRI Grant no. 2006‐35200‐16580 from the USDA, Bioactive Food Components for Optimal Health Program (31.0)
Combining Experimental and Mathematical Modeling to Reveal Mechanisms of Macrophage‐Dependent Left Ventricular Remodeling
Authors: Jin Yufang , Han Haichao , Berger Jamie , Dai Qiuxia , Lindsey Merry 
Published: June 2021

Progressive remodeling of the left ventricle (LV) following myocardial infarction (MI) can lead to congestive heart failure, but the underlying initiation factors remain poorly defined. The objective of this study, accordingly, was to elucidate the regulatory mechanisms of LV remodeling using integrated computational and experimental approaches. We developed the first mathematical model to study LV remodeling post‐MI by quantifying the dynamic balance between extracellular matrix (ECM) construction and destruction. Our experimental results of post‐MI ECM gene expression and plasma analyte levels in C57/BL6J mice and cardiac fibroblast ECM gene responses to transforming growth factor‐β1 (TGF‐β1) showed that key factors in LV remodeling included macrophages, fibroblasts, TGF‐β1, matrix metalloproteinase‐9, and collagen content. The mathematical model incorporated these key factors and demonstrated that TGF‐β1 stimuli and MMP‐9 interventions with different strengths and interfering time lead to different LV remodeling responses. The predictions fell within the range of experimental measurements for these interventions, providing validation for the model. In conclusion, our results demonstrate that the balance between ECM synthesis and degradation controlled by interactions of specific key factors determine net LV remodeling outcomes. Our mathematical model based on the balance between ECM construction and destruction predicts remodeling outcomes and provides a useful tool to study post‐MI LV regulatory mechanisms.The authors acknowledge grant support from NSF 0644646, 0602834 (to HH), NIH R01 HL75360 and AHA GIA 0855119F (to MLL), NSF 0649172 and NIH 1SC2 HL101430 (to YJ).
A Conceptual Cellular Interaction Model of Left Ventricular Remodeling: Dynamic Network with Exit‐Entry Evolution Strategy
Authors: Wang Yunji , Han Haichao , Yang Jack , Lindsey Merry , Jin Yufang 
Published: June 2021

Progressive remodeling of the left ventricle (LV) following myocardial infarction involves spatial‐temporal interactions among multiple cell types, including myocytes, neutrophils, macrophages, endothelial cells, and fibroblasts. Interactions associated with cellular functional adaption determine cell populations and remodeling outcomes. However, little is known about the relationship among cell populations, interaction strength, and network structure. The objective of this study was to illustrate the effect of cell‐cell interactions on the evolution of cell population in LV remodeling. This research proposed a conceptual cellular interaction model based on a recent established graphic network. Stability analysis was performed to investigate the effects of the interaction strengths on the cellular population in the dynamic network consisting of two cell‐types. Our numerical simulations demonstrated that the interaction strength between two types of cells, number of interaction links, and initial cell population ratio, all together, determine the evolution profiles of the cell population in the network. Our model predicted three potential scenarios of cell population evolution. The results on stability analysis can be used as a useful tool to predict the spatial‐temporal changes of cell populations.The authors acknowledge grant support from NSF 0644646, 0602834 (to HH), NIH R01 HL75360 and AHA GIA 0855119F (to MLL), NSF 0649172 and NIH 1SC2 HL101430 (to YJ).
Strain array for cell culture: cyclic strain affects epithelial cell spreading
Authors: Simmons Chelsey , Sim Joo Yong , Bächtold Philipp , Pruitt Beth 
Published: June 2021

We have designed, fabricated and characterized a strain array (6 mm well plate format) for cell culture that applies different strain to cells plated in each row of wells on the device. This device is capable of applying 0%, 2%, 4%, 7% or 17% strain to distinct samples with separate perfusion paths using a pressure difference of 10kPa. Our device has 25 wells but mimics the geometry of a standard 96‐well plate (for compatibility with automated plate readers and other technologies) and leaves samples easily accessible to assay. Further, samples experiencing different strain fields have separate perfusion pathways. These capabilities are useful in experiments to examine mechanotransduction mechanisms, specifically sensitivity to applied strain. Madin‐Darby Canine Kidney epithelial cells were attached on the device for 3 hrs then cyclically strained at 1Hz. Cells exhibited different patterns of spreading and localization of GFP‐tagged vinculin in response to strain levels over time.This work is funded by NSF EFRI CBE0735551, NIH R21 HL089027, and CIRM RC1‐00151‐1. CS is funded by the Smittcamp Graduate Fellowship of the Stanford Cardiovascular Institute and an NSF Graduate Research Fellowship.
Functional implications of temporal bone pneumatization in hominids
Authors: Hill Cheryl A. 
Published: June 2021

Numerous functions have been proposed for the pneumatized spaces of the skull, ranging from acoustic isolation from self‐generated sounds to pressure equalization around the tympanic membrane. By quantifying pneumatized spaces across a number of species it may be possible to elucidate possible functions based on shared morphology and/or phylogenetic history. The purpose of this study was to compare the morphology of pneumatized portions of the temporal bone in extant hominids to determine possible hypotheses about the functions of those spaces.High resolution computed tomography scans of the temporal bone were acquired from humans (N=10), chimpanzees (N=10), gorillas (N=10), and bonobos (N=1). Surface areas and volumes of pneumatized spaces were collected from the entire temporal bone using Amira©. Volumes of interest were cropped from the temporal bone using Quant3D software and analyzed for bone volume fractions, trabecular thickness and anisotropy. These measures were compared according to 1) phylogenetic history and 2) shared craniofacial morphology.Results indicate that the morphology of pneumatized spaces within the hominid temporal bone is not consistently similar or different according to either species membership or shared craniofacial morphology. These findings indicate that the possible functions of pneumatized spaces in the hominid temporal bone are complex and remain elusive.Research supported by NSF (BCS‐052493) and Leakey Foundation.
Obese rat pregnancy impaired fetal development independent of diet and involved the placental WNT pathway
Authors: Strakovsky Rita , Pan Yuan‐Xiang 
Published: June 2021

Maternal obesity has been associated with a multitude of maternal morbidities, and epidemiological studies show that children of obese mothers are at higher risk for obesity, diabetes, hypertension, and heart disease. A healthy diet is the primary recommendation for pregnant women. However, it is unclear whether this prescription will rescue an obese pregnancy. Because the placenta is the primary transport and sensing mechanism between the mother and fetus, this study intends to show that maternal obesity in rat may negatively affect the offspring through the placental WNT pathway regardless of gestational diet. To accomplish this, rats from the Obese Resistant (OR) and Obese Prone (OP) strains were fed the AIN93G (Bal) or a 45% fat (HF) diets throughout pregnancy, and c‐sections were performed on gestational day 21, followed by placental qRT‐PCR analysis. Offspring of OP dams were significantly lighter and had significantly higher blood glucose than OR, with no effect from the HF diet on OP offspring. Placental Axin2, Dkk1, sFRP5 and TNFα, were significantly different in OP animals when compared to OR, but were not affected by the HF diet in OP, and were affected in OR dams. These results suggest that maternal obesity is associated with alterations in the placental WNT pathway as well as fetal physiology, but that a balanced diet in pregnancy may not be enough to prevent the negative fetal outcomes of obese gestation.Grant Funding Source: USDA
Maternal Low Protein Diet Induces Amino Acid Response (AAR) Pathway in the Liver of Dam Rat
Authors: Wang Huan , Pan Yuan‐xiang 
Published: June 2021

ObjectiveAmino acid response (AAR) pathway reacts to deficiency of dietary protein or an imbalance of essential amino acids. The effects of low protein diet to dam rats during gestation have not been reported. The present study is designed to investigate the impacts of maternal diets on activation of the AAR pathway in dam rats.MethodsTimed‐pregnant Sprague‐Dawley rats were fed on one of the two isocaloric diets, control (20 kcal% protein, 64 kcal% carbohydrate) or low protein diet (8 kcal% protein, 76 kcal% carbohydrate) during gestation and lactation. The livers of dam rats were collected and used to isolate mRNA and protein.ResultsLow protein diet induces phosphorylation of eIF2alpha and ERK in the liver of dam rats. There were significantly changes in mRNA expression of the downstream target genes in the AAR pathway, such as ASNS (asparagine synthetase), ATF3 (activation transcription factor 3), CHOP(C/EBP homology protein), and SNAT2 (sodium‐coupled neutral amino acid transporter 2).ConclusionMaternal high carbohydrate/low‐protein diets fed during gestation and lactation regulates the activation of the AAR pathway in the livers of dam rats.Grant Funding Source: USDA
A High Protein Diet Induces Intestinal Iron Transporter Expression and Improves Iron Absorption in Rats
Authors: Cucchi Carrie , Gaffney‐Stomberg Erin , Sun Ben‐Hua , Kerstetter Jane , Insogna Karl 
Published: June 2021

Dietary protein has been shown to increase iron (Fe) absorption by improving bioavailability. Little data are available on the effect of dietary protein on Fe transporter expression.As part of a study designed to evaluate the impact of dietary protein on mineral homeostasis, a whole genome microarray screen was performed using RNA prepared from duodenal intestinocytes of rats ingesting low (5%) or high (40%) casein diets for one week. Of 91 genes that were significantly up‐regulated in the 40% group, 3 were Fe transporters. DMT1 expression was 2.5‐fold greater in the 40% compared to the 5% group, while Cybrd1 and Tfrc were 1.6‐fold greater. Q‐PCR using the same RNA employed in the microarray screen confirmed these findings.When compared to the level of expression on a 20% diet (usual rat chow), DMT1 was 4‐fold higher in the 40% group (p<0.001), Cybrd1 was 2.2‐fold higher (p<0.05) while Tfrc was not different.To determine if the observed changes in expression of DMT1 and Cybrd1 were associated with changes in Fe homeostasis, a balance study was performed in rats ingesting 5, 20 and 40% protein diets. By the Kruskal‐Wallis test there was a significant effect of dietary protein on Fe balance and by post hoc analysis Fe absorption was greater in animals consuming the 40% vs. 5% diet (p<0.01).These data suggest that increasing dietary protein augments Fe absorption in part by inducing the expression of duodenal Fe transporters.Grant Funding Source: USDA
Characterization of plasma ceruloplasmin activity and expression following dietary copper deficiency
Authors: Prohaska Joseph , Broderius Margaret , Mostad Elise , Wendroth Krista 
Published: June 2021

Ceruloplasmin (CP) is a multicopper oxidase and the most abundant copper binding protein in mammalian plasma. Loss of function mutations in humans or experimental deletion in mice result in iron overload consistent with CP's putative ferroxidase function. Prior work suggested plasma may contain multiple ferroxidases. Studies were conducted in Holtzman rats, albino mice, Cp −/− mice, and adult humans to investigate the copper‐iron interaction and further characterize CP as a biomarker. Dietary copper‐deficient (CuD) rats and mice were produced using a modified AIN‐76A diet. Results confirmed that o‐dianisidine is a better substrate than paraphenylene diamine (PPD) for assessing diamine oxidase activity of Cp. Plasma from CuD rat dams and pups, and CuD and Cp −/− mice contained no detectable Cp diamine oxidase activity. Importantly, following western blotting no detectable ferroxidase activity was observed for CuD rats, mice, or Cp −/− mice compared to robust activity for copper‐adequate (CuA) rodent controls. Immunoblot protocols detected major reductions (60–90%) in Cp protein in plasma of CuD rodents but no alteration in liver mRNA levels by qRT‐PCR. Data support that apo‐Cp is less stable than holo‐Cp. Further research is needed to explain normal plasma iron in CuD mice. Reduction in CP activity is a sensitive biomarker for copper deficiency.Supported by NIH HD‐39708 and USDA NIFA 2006‐35200‐17378.
How the family started: Origins of hominids
Authors: Ward Carol 
Published: June 2021

The transition to committed bipedality is a key characteristic of hominins. Fossil evidence documenting hominin origins has grown substantially, but much of our understanding of the earliest members of the Australopithecus‐human clade still comes from Au. afarensis. Understanding selective pressures shaping Australopithecus requires knowledge of its ancestral morphology. Here I compare evidence from Miocene and Pliocene hominoids and consider the implications of their morphology for reconstructing the ancestral hominin morphology. Data indicate high levels homoplasy among hominoids, and that ancestral hominins likely differed from extant great apes in important ways, such as pelvis, lumbar and hand proportions. However, some characteristic of extant apes are likely primitive. Homoplasy is common and involved different experiments in exploiting arboreal habitats. So rather than thinking about progressive stages leading towards Australopithecus from an ancestral taxon like Proconsul through one like a modern great ape or not, we need to refocus efforts to explore the detailed similarities and differences among extant and extinct apes, and the diversity of their locomotor adaptations.Research supported by NSF and LSB Leakey Foundation.
Association of age, gender and weight status with willingness to taste fruits and vegetables among elementary school children
Authors: Lakkakula Anantha , Wong Wei‐Ping , Zanovec Michael , Pierce Sarah , Tuuri Georgianna 
Published: June 2021

This study examined the association between age, gender, and weight status with willingness to try fruits and vegetables offered during a tasting program. A total of 312 first, third, and fifth graders (51% boys, 34% first graders, and 30% third graders) attending low‐income public elementary schools in southeastern Louisiana participated. Prior to tasting, children were measured for height and weight. Small portions of 4 vegetables (carrots, peas, tomatoes and bell peppers) and 4 fruits (apricots, cantaloupe, peaches and pears) were offered. The children recorded whether they “chewed and swallowed”, “spit it into the napkin” or “did not taste” each item. Scores for vegetables and fruits were examined separately. A logistic regression analysis indicated that first graders were 4.6 times more willing to taste 2 or more vegetables provided when compared to fifth graders (OR = 4.6, 95% CI: 2.31, 9.14; p < 0.01), and third graders were 8.1 times more willing to taste 2 or more vegetables provided when compared to fifth graders (OR = 8.1, 95% CI: 3.65,18.22; p < 0.01). No differences were observed between first and third graders, gender or weight status group and willingness to try vegetables. No associations were found between willingness to try fruits and age, gender or weight group. Younger elementary school children were more willing to try vegetables than older children. Supported by USDA grant #2009‐35200‐05287.Grant Funding Source: USDA grant #2009‐35200‐05287
Maturity aggravates sepsis‐associated skeletal muscle catabolism in growing pigs.
Authors: Orellana Renán A , Suryawan Agus , Gazzaneo María C , Wilson Fiona A , Nguyen Hanh V , Fiorotto Marta L , Davis Teresa A 
Published: June 2021

Synthesis and accretion of muscle protein is elevated in neonates and decreases with development. During sepsis, muscle protein synthesis is reduced, but the effect of development on the metabolic response to sepsis in skeletal muscle is not well understood. Fasted 7‐ and 26‐d‐old pigs were infused for 8 h with LPS (0 and 10 μg•kg−1•hr−1) and fractional protein synthesis rates (FSR) and translation and degradation signals were determined in longissimus dorsi muscle (n=5–7/group/age). α‐Actin in serum, and FSR, ribosomal abundance, and caspase‐3 abundance in muscle were greater in 7‐ than 26 d‐old pigs, indicating a higher baseline protein turnover in the younger pigs. In muscle, LPS decreased FSR, protein synthetic efficiency, and eIF4G phosphorylation and increased AMPK phosphorylation and MURF‐1 and atrogin‐1 abundance in both age groups. Serum 3‐methylhistidine and α‐actin levels and caspase‐3 abundance in muscle increased in 26‐ but not in 7‐d‐old pigs in response to LPS. The results suggest that the mechanisms regulating protein accretion in skeletal muscle in neonatal pigs during sepsis are influenced by development such that the LPS‐induced muscle catabolism becomes more severe as maturation advances. NIH AR51563, NIH AR44474, and USDA 6250‐51000‐040Grant Funding Source: NIH AR44474, and USDA 6250‐51000‐040
Glycemic index does not affect overall glucagon like peptide – 1 levels in healthy overweight women
Authors: Casey Shavawn Marie , Horn William , Hembrooke Tara , Keim Nancy 
Published: June 2021

BackgroundGlucagon‐like peptide‐1 (GLP‐1) is secreted in response to food ingestion specifically carbohydrate‐rich food sources. GLP‐1 is involved in a variety of physiologic functions including: regulation of plasma glucose, inhibition of gastric emptying, and decreasing food intake by increasing satiety.MethodsA randomized cross‐over design was used to measure the incretin response to 2 standardized breakfast meals: a high glycemic index (HGI) meal and a low glycemic index (LGI) meal. Both meals were matched for energy and macronutrient contents (54% C, 15% P, & 31% F). Seven healthy, overweight women participated. Blood samples were obtained before and for 8 hours following consumption of the test meals. Plasma GLP‐1 [(7–36) and (7–37) amide] quantification was done by active ELISA assay.ResultsThere were no differences in fasting plasma GLP‐1 or in postprandial GLP‐1 in response to the HGI and LGI breakfast meals.Grant Funding Source: general funds and the USDA, ARS WHNRCGrant Funding Source: USDA
Maternal Low Protein Diet Induces ATF3 but not ASNS Expression in Liver of Female Offspring Through Amino Acid Response (AAR) Pathway
Authors: Zhou Dan , Pan Yuan Xiang 
Published: June 2021

ObjectiveTo investigate the impact of maternal low protein on programming of AAR pathway.MethodSprague‐Dawley rats were fed a control (18% protein) or low protein diet (LP, 9% protein) during gestation. Liver from female offspring was collected at 38 days of age to analyze expression and histone modification of genes in AAR pathway.Resultexpression of ATF3 in LP group increased significantly. ATF4 and p‐eIF2alpha, key upstream factors in AAR pathway, were up‐regulated as well. Chromatin immunoprecipitation assay confirmed that Pol II and ATF4 binding was increased at the ATF3 promoter while there was a decrease of ATF3 and C/EBPbeta binding. On the other hand, promoter of the downstream gene ASNS showed a different profile. Acetylated histone H4, a marker for an open chromatin was increased at the ASNS promoter, along with an increased binding of ATF4, ATF3 and C/EBPbeta. However, tri‐methyl histone H3 at lysine 9, a marker for chromatin silencing, was increased in LP group, possibly leading to no change in Pol II binding and therefore no change in ASNS gene expression level.ConclusionMaternal low protein diet programs AAR pathway in liver of female offspring. This programming occurs at upstream of AAR pathway, mainly affecting gene expression of transcription factors, including ATF4 and ATF3. Furthermore this may prime the downstream target genes such as ASNS to respond to low protein environment later.Grant Funding Source: USDA