bluuebunny/crossref_metadata_2025 huggingface dataset:
Oligomycin, a Complex V Inhibitor, Decreases Left Ventricular Contractility in Isolated Rabbit Heart
Authors: Fang Mei , Qu Yusheng , Gao BaoXi , Acton Paul , Hernandez Rocio , Senal Ihsan , Lawrence Jeff , Vargas Hugo M.
Published: June 2021

The isolated rabbit heart (IRH) model has been used to investigate the proarrhythmic potential of marketed drugs or drugs intended for market. In addition, hemodynamic effects of a compound on left ventricular contractility can be measured in this model. We have validated negative and positive inotropic agents, including milrinone and diltiazem.

Oligomycin is a natural antibiotic which inhibits mitochondrial complex V (ATP synthase). It inhibited both solution based Complex V activity with an IC50 of 0.34 μM and inhibited immuno‐Captured Complex V activity with an IC50 of 0.053 μM. Cardiac contraction requires high‐energy utilization and therefore is exquisitely sensitive to energy depletion. To test the effect of oligomycin on left ventricular contractility, IRH was perfused with increasing concentrations (0.1, 0.3, 1, and 3 μM) for 20 min at each concentration or with a single concentration of 0.3μM for 60 min. Oligomycin was found to decrease LV contractility in a dose‐ and time‐dependent manner. The time‐dependent effects of oligomycin as well as the prominent prolongation of PR intervals distinguished it from the standard Ca channel inhibitor, diltiazem. Our data suggests that oligomycin decreases LV contractility of IRH by primarily inhibiting mitochondrial Complex V.
Oligomycin A Induced Toxicity and Profound Hemodynamic Effects in Intact Sprague‐Dawley Rats
Authors: Chui Ray , Derakhchan Kathy , Vargas Hugo M
Published: June 2021

Oligomycin A (oligo) inhibits mitochondrial complex V that leads to impaired energy formation in high energy demand organs like heart. The purpose of this study was to determine the effects of oligo on the cardiovascular system of conscious rats. Sprague‐Dawley (SD) rats were implanted with telemetry devices and assigned to one of four groups: vehicle, 0.1, 0.5 and 1 mg/kg, with n=6 for each group. All doses were via intraperitoneal administration and data was collected continuously for 48 hours post‐dose. Both dose‐dependent hypotension and bradycardia were observed in all groups dosed with oligo. At low dose, a 10–20 mmHg decrease in mean arterial pressure (MAP) was observed, along with a 25 beat/min (bpm) decrease in heart rate (HR). At mid dose, MAP decreased 10–30 mmHg and HR decreased 25–50 bpm. At high dose, MAP decreased >40 mmHg and HR decreased >150 bpm. Mid and high dose oligo exhibited lethality. Since ATP depletion would be expected to reduce cardiac contractility, a follow‐up study evaluated the effects of 1 mg/kg of oligo (1 hour infusion) on cardiac contractility in anesthetized rats. Oligo infusion caused significant negative inotropy, HR reduction and lethality in this model. These results demonstrate that oligo has profound effects on the cardiovascular system in conscious and anesthetized SD rats. Animals that died had exhibited severe hypotension, bradycardia and reduced cardiac contractility.
Increased hypothalamic c‐Fos expression and anxiety‐like behaviors by oral exposure to capsaicin in rats
Authors: Jahng Jeong Won , Kim Jin Young , Yoo Sang Bae , Lee Jong‐Ho
Published: June 2021

In this study, we examined the neurobehavioral outcome of repeated oral exposures to capsaicin in rats. Oral application of 0.02% capsaicin was performed once daily and the rats were subjected to the behavioral tests following 10 days of oral capsaicin or sacrificed for c‐Fos immunohistochemistry at 1 h after the first oral capsaicin. The control group received water orally instead of capsaicin, and for immunohistochemistry, rats were transcardially perfused with 4% paraformaldehyde. Total ambulatory counts and the distance travelled in the activity chamber did not differ between the capsaicin and the control groups; however, the central zone activities were decreased in the capsaicin group. In the elevated‐plus maze test, capsaicin rats spent more time in the closed arms than control rats. In Porsolt swim test, swimming duration was decreased, struggling increased, in capsaicin rats without statistical significance. Oral capsaicin exposure significantly increased c‐Fos expression not only in the nucleus tractus of solitarius but also in the paraventricular nucleus. Results suggest that a long‐term oral exposure to capsaicin may increase anxiety‐like behaviors, likely by affecting neural plasticity of the hypothalamic neurons. Supported by NRF(20100003642)
THE EFFECTS OF GLOBAL CLIMATE CHANGE ON THE ENERGETICS OF AN ENDANGERED DESERT PUPFISH
Authors: Hillyard Stanley D. , Lopez Eshani , Harris Sean , van Breukelen Frank
Published: June 2021

When Pleistocene waters receded from the Death Valley region, once continuous pupfish populations became stranded in isolated warm springs. One of these springs, Devils Hole, maintains a temperature of 33–34° C year round except on a shallow ledge where temperatures may range from 28 to 39° C on a seasonal basis. Between 1995 and 2006 population estimates declined from a maximum of over 500 to only 38 individuals. Supplemental feeding, beginning in 2007, resulted in recovery to approximately 120 fish. We have estimated energetic requirements from oxygen consumption measurements with hybrids between Devils Hole and Ash Meadows Pupfish (Cyprinodon diabolis x C. nevadensis mionectes) and found the population decline and subsequent recovery to be consistent with the decline in primary production and the energetic value of the supplemental diet. We have also found that oxygen consumption increases as predicted between 28 and 31° C, with Q10 values between 2 and 3 but does not further increase between 31 and 34° C indicating an inability to sustain oxidative metabolism at temperatures normally encountered in Devils Hole. We contend that although these fish inhabit warm springs, they are poorly adapted to thrive at warm temperatures. Modest temperature increases associated with global climate change may be applying an energetic stress that will result in the extirpation of these and other desert pupfish populations.
Associations between Leptin, sCD40L and Metabolic Syndrome Components in Black Females
Authors: Many Gina Marie , Onyewu Chiatogu , Debessai Sembel , JoAnn Kuo , Spurney Christopher , Whitney Barfield , Hurtado Maria‐Eugenia , Klein Catherine J. , Schweitzer Amy , Hoffman Eric P.
Published: June 2021

Less Blacks meet diagnostic criteria for metabolic syndrome compared to Whites, despite Blacks having a greater prevalence of obesity. Early biomarkers of obesity associated metabolic dysregulation are needed to identify high‐risk individuals and substantiate successful interventions. This study investigated associations between plasma leptin, soluble CD40 ligand (sCD40L), and metabolic syndrome components in healthy Black college‐aged females (n=37). Metabolic syndrome phenotypes assessed included: waist circumference (WC), resting blood pressure (BP), fasting plasma glucose, high density cholesterol (HDL), and triglycerides (TG). sCD40L and leptin showed the strongest correlation to WC (r=0.42, p=0.02; r=0.56, p<0.01, respectively) relative to other metabolic syndrome components [glucose (r=0.33, p=0.04), HDL (r=0.30, p>0.05), TG (r=0.29, NS), systolic BP (r=0.18, NS) and diastolic BP (r=0.13, NS)]. Correlations between sCD40L and WC in this young cohort were higher than previously reported in White adults (r=0.24, p<0.01) (Unek et al., 2008). These findings suggest the potential utility of sCD40L as an early biomarker of obesity‐associated metabolic disease in healthy young Black populations.

Support: DC‐Baltimore Child Health Disparities Research (2P20MD000198‐06) and the National Center for Research Resources (M01RR020359 & UL1RR031988)
Transgenic over‐expression of C1q/TNF Related Protein‐1 (CTRP1) in mice increases fatty acid oxidation and reduces adiposity on a high‐fat diet
Authors: Peterson Jonathan M , Aja Susan M , Wei Zhikui , Seldin Marcus , Wong G. William
Published: June 2021

Since the discoveries of leptin, the contribution of adipose tissue as an active endocrine organ has become an essential consideration for the understanding of metabolic diseases. Our laboratory recently discovered a family of novel secreted proteins homologous to adiponectin, designated as C1q/TNF‐related proteins 1‐10 (CTRP1‐10). This study focuses on the metabolic function of CTRP1, a circulating endocrine factor that is produced by adipose tissue. Here we show that circulating levels of CTRP1 are significantly elevated in ob/ob and diet‐induced obese mice relative to lean controls. We generated a transgenic mouse model that over‐expresses CTRP1 (CTRP1‐Tg). When fed a high‐fat diet, we observed a 12 % decrease in body weight gain in CTRP1‐Tg mice relative to control littermates, primarily caused by a reduction in fat mass (−29%), with no significant change in lean body mass. Further, the reduction in adiposity is not due to any changes in food intake or physical activity levels. Instead, this is due to enhanced whole body fatty acid oxidation and energy expenditure based on indirect calorimetry study. Additionally, diet‐induced obese CTRP1‐Tg mice demonstrate increased sensitivity to insulin and increased tolerance to pyruvate relative to control mice. Together, this study provides the first in vivo evidence that CTRP1 is a bona fide adipokine that regulates energy storage and expenditure.
The Change of % Body Fat, Physical Fitness and Blood Lipids according to the Order of Exercises on Army Population in Korea
Authors: Jin Haeng Mi , Shim Jae Geun , Kim Ok Ja , Kim Hee Eun , Kim Jung Eun
Published: June 2021

The purpose of this study was to investigate the effects of the exercise order on %body fat, physical fitness and blood lipids of army population in Korea. 96 armies were divided into 3 groups, group 1 (anaerobic/aerobic order) (n=24), group 2 (aerobic/anaerobic order) (n=24) and control (no exercise) (n=48). During 12 wks, armies had taken exercise 70 minutes a day, 3 times a week and after exercise, %body fat, physical fitness and blood lipid profiles were measured. There was no statistical difference in %body fat among groups, however, group 1 noticeably reduced compared to other groups. As a result of physical fitness measurement, group 1 and group 2 presented significant increase in flexibility than the control group. In addition, both groups also significantly improved agility compared to the control group. Muscular power, balance, reflex and endurance were also increased in the group 1 and the group 2 but there were no significant differences compared to the control group. There were decreases of blood total cholesterol and triglyceride in the group 1 but values were not significantly different with other groups. The order of exercise did not affect the changes of %body fat, physical fitness and blood lipid profiles, however, regular exercise may improve body composition, physical fitness and blood lipid profiles in army population.
Fiber Type Heterogeneity for Glucose Uptake by Single IIA, IIB, IIX and IIB/X Fibers from Rat Epitrochlearis Muscle
Authors: MacKrell James , Cartee Gregory D.
Published: June 2021

Models for studying glucose uptake (GU) by cultured muscle cells are valuable, but lack important characteristics of authentic skeletal muscle. Studies that evaluate skeletal muscle must be mindful of its fiber type heterogeneity. Our aim was to determine the effect of fiber type on GU by single fibers from skeletal muscle employing a novel single fiber GU method with a standard method for classifying fiber type (myosin heavy chain, MHC). Rat epitrochlearis muscles underwent an ex vivo incubation protocol with [3H]‐2‐deoxyglucose (2DG) ± 12nM insulin. Following collagenase treatment of the muscle, non‐permeabilized single fibers were dissected and analyzed for fiber volume, MHC, and GU (2DG accumulation relative to fiber volume, nmol/mm3). Basal GU did not differ among fiber types. ANOVA revealed a significant difference for insulin‐stimulated GU between IIA fibers vs. all other measured fiber types (IIA > IIB, IIX, IIB/X), and a significant difference between IIB/X vs. IIB fibers (IIB/X > IIB). Insulin‐stimulated GU was independently inhibited by cytochalasin B (25μM) or wortmannin (0.5μM), verifying fiber 2DG accumulation occurred via glucose transporter‐mediated uptake and in a PI3K‐dependent manner. The current data extend insights from whole muscle experiments which are limited because they cannot unambiguously identify differences attributable to fiber types.

Support : NIH (NIDDK 71771 & AG10026)
Enhancement of the astaxanthin production by culture conditions and mutagenesis in Paracoccus haeundaensis
Authors: Kim Young Tae
Published: June 2021

Astaxanthin represents a group of valuable molecules for pharmaceuticals, food and feed industries. In order to enhance the production of astaxanthin in Paracoccus haeundaensis, we have used various culture conditions using carbon/nitrogen sources and hydrogen peroxide. When carbon sources (lactose, fructose, glucose and mannitol) and nitrogen sources (sodium nitrate and potassium nitrate) were used, the production of astaxanthin was increased. The optimal C/N ratio was 3% carbon and 1% nitrogen and the astaxanthin production was 1.5 folds increased (641.17μg/g to 973.12μg/g dry cell weight (DCW)). The hydrogen peroxide was 1%, the product of astaxanthin was the highest. When H2O2 and C/N sources were the simultaneous added, the production of astaxanthin was increased approximately 1.83 folds (1019.16μg/g DCW). Cultures of Paracoccus haeundaensis were exposed to mutagens such as UV and ethylmethanesulfonate (EMS). The results showed that the survival rate decreased with the increase in UV exposure time and increase in EMS concentration. The hyper‐production mutant of astaxanthin was produced by UV irradiation (20 min exposure) with EMS treatment (0.4 M concentration). The isolated mutants exhibited an increase of 3.82 folds in astaxanthin production compared to the untreated initial strain. This genetically stable mutant strain may be a suitable candidate for the industrial production of astaxanthin.
Caspase‐3 is activated by intrinsic apoptotic pathways during mechanical ventilation
Authors: Nelson W. Bradley , Smuder Ashley J. , Hudson Mathew B. , Talbert Erin E. , Powers Scott K.
Published: June 2021

Rationale

Diaphragmatic weakness is a well‐documented response to prolonged mechanical ventilation (MV). Several key proteases are activated during prolonged MV. Specifically, caspase‐3 has been shown to be required for diaphragmatic weakness. However, the mechanisms by which caspase‐3 is activated is unknown. We tested the hypothesis that during MV, caspase‐3 is activated by an intrinsic pathway.

Methods

Female Sprague‐Dawley rats (3 months old) were divided into two groups: 1) control and 2) animals that were mechanically ventilated for 12 hrs.

Results

Compared to control, MV resulted in an increase in the caspase‐3 specific cleavage product of alpha‐II spectrin and increased caspase‐3 activity in the diaphragm. Likewise, after MV, both caspase‐9 and caspase‐12 activities in the diaphragm were significantly higher than control. In contrast, there was no increase in diaphragmatic caspase‐8 activity after MV.

Conclusion

These results confirm our hypothesis that during prolonged MV, diaphragmatic caspase‐3 is activated by both mitochondrial (caspase‐9) and sarcoplasmic reticulum (caspase‐12) mediated pathways rather than the external death ligand (caspase‐8) pathway. Supported by the NIH RO1 HL087839 awarded to SKP.
Calorie Restriction Increases In Vivo Glucose Uptake and Insulin Signaling in Rat Skeletal Muscle
Authors: Sequea Donel Angelo , Sharma Naveen , Castorena Carlos M , Qi Nathan , Cartee Gregory D
Published: June 2021

Calorie restriction (CR; eating ~60% of ad libitum, AL, intake) enhances insulin‐mediated glucose uptake (GU) and Akt phosphorylation in isolated rat skeletal muscle. The aim of this study was to determine if CR (6mo duration begun at 3mo‐old) also improves in vivo glucose uptake and Akt phosphorylation in skeletal muscle of male, Fischer 344 Brown Norway rats undergoing a euglycemic‐hyperinsulinemic clamp. Glucose and insulin were infused to achieve similar plasma values for glucose (119±2mg/dl for AL and 119±5mg/dl for CR) and insulin (161±9μU/ml for AL and 156±8μU/ml for CR) in the 2 groups. Glucose infusion rate (mg/kg/min) of the CR group (33 ±2) was significantly higher than the AL group (16 ±1), and radiolabeled 2‐deoxyglucose uptake (μg/g/min) was also significantly increased for the epitrochlearis muscle of CR (24 ±2) vs. AL (14 ±1) rats. CR vs. AL group had greater values for pS473‐Akt and pT642‐Akt substrate of 160 kDa (AS160), but not for pY1162/1163‐insulin receptor in insulin‐stimulated epitrochlearis. The enhanced whole body insulin sensitivity in CR vs. AL rats was likely attributable, at least in part, to elevated insulin‐mediated GU of skeletal muscle secondary to enhanced pS473‐Akt and pT642‐AS160 despite unaltered pY1162/1163‐insulin receptor. Support: NIH (R01‐AG10026 and T32‐AG000114).
Ronacaleret retards renal injury with preserving klotho in 5/6‐nephrectomized rats
Authors: Takenaka Tsuneo , Inoue Tsutomu , Suzuki Hiromichi
Published: June 2021

We have previously reported that calcimimetics reduces klotho. In the present study, effects of ronacaleret, a calcilytic, on renal injury was assessed in four groups of rats (n=6–10 for each group); 5/6‐nephrectomized Wister rats as a control (C), those treated with ronacaleret (150 mg/kg/day) (R), rats treated with calcitriol (30 ng/kg/day) (V), and rats treated with both ronacalcet and calcitriol (R+V). Three months later, rats were killed with over‐anesthesia, and harvested remnant kidney for analysis. Albuminuria was lower in R, V and R+V than C group. Creatinine clearance was elevated in R and V than C group. Serum calcium was increased in R+V than C group. Fractional phosphate excretion was increased in R, V and R+V compared to C group, and serum phosphate was reduced in R group. FGF23 was lower in R and higher in V and R+V than C group. PCR analysis revealed that compared to C, renal klotho expression was elevated in R and V groups. The present data indicate that ronacaleret preserved klotho expression and renal function with reduction in serum phosphate and albuminuria in 5/6‐nephroctomized rats. Our findings demonstrate that vitamin D prevented declines in klotho expression and renal function, suppressing albuminuria. The current results provide the evidence that hypercalcemia decreases klotho expression, participating in the progression of renal dysfunction.
Inhibition of the Signaling Function of Na/K‐ATPase Produces Salt‐Sensitive Hypertension
Authors: Chen Yiliang , Liu Jiang , Liu Changxuan , Shapiro Joseph I , Xie Zijian
Published: June 2021

We have previously shown that the Na/K‐ATPase (NKA) acts as a receptor for cardiotonic steroids such as ouabain and salt to regulate Src kinase activities (Tian et al., Mol Biol Cell, 2006, 17:317; Ye et al., JBC, 2011). Here, we test the physiological role of this newly discovered signaling mechanism. Activation of NKA signaling by ouabain leads to endocytosis of both NKA and NHE3, which causes a reduction of transcellular Na+ transport in LLC‐PK1 cell monolayer. Expression of the N‐terminus of NKA α1 subunit (NT), which functions as a dominant negative mutant, specifically blocks the NKA signaling and prevents ouabain‐induced inhibition of transcellular Na+ transport. These in vitro experiments suggest that the signaling NKA be involved in the regulation of renal sodium handling and therefore, may play a role in the control of blood pressure (BP). To test this hypothesis in vivo, we have generated NT‐YFP transgenic mice (NT mice) and measured BP after mice were fed with either normal (0.5% NaCl) or high salt diet (4.0%). The high salt diet increased BP from 110 mmHg to 160 mmHg in NT mice, but not in age‐matched littermates. Moreover, renal functional curves reveal a salt‐sensitive hypertension phenotype in NT mice.
Functional homeostatic‐excitable cell model for CO2 chemosensing
Authors: Cordovez Juan , Quintero Maria Carolina , Solomon Irene C
Published: June 2021

Work from our laboratory has focused on developing a comprehensive mathematical model of central respiratory CO2 chemoreceptors that considers the homeostatic response of the cell an important factor for transduction of the signal(s) into a change in firing rate. A distinctive feature of our model, and prerequisite for studying cellular functions in addition to the electrical response, is that fluxes are described by the permeability‐based Goldman‐Hodgkin‐Katz (GHK) equation as opposed to a typical conductance‐based Hodgkin‐Huxley (HH) approach. Since experimental measurements of permeability are rare, we employ theoretical approaches to estimate parameters for each ion channel incorporated into our model. Our model behavior is then compared to that of a published comparable HH model. Approaches implemented include fitting simulated voltage‐clamp experiments, steady‐state I‐V curves, and least squares analysis. Here, we isolate voltage‐sensitive Na+ current and delayed‐rectifier K+ current to form a minimal model for excitability and explore its dynamical features (i.e., stability, bifurcations). Implementation of this approach demonstrates that our GHK model yields a richer dynamical response than the HH model. We propose that this approach be used to generate more realistic models for studies of neuronal excitability in mammalian CO2 chemoreceptors. Supported by NS045321 and HL63175.
Enzymatic and mass spectral analysis of mutant and wild‐type selenomethionyl‐dihydrofolate reductase
Authors: Broderick Kathleen Marie , Boles Jeffrey O
Published: June 2021

The biosynthetic incorporation of unnatural amino acids, primarily selenomethionine, has been used for over a decade to facilitate structural determination of proteins. This substitution has been shown to lead to instability and incomplete incorporation in some target proteins. In this study, the stability, level of incorporation and catalytic activity of selenomethionyl‐dihydrofolate reductase (Se‐Met DHFR) and wild type DHFR have been analyzed for catalytic activity and stability. The sensitivity to cyanogen bromide and trypsin for mass spectral analysis will be presented. A methionine to leucine mutation at position 6, also subjected to these analyses for both the wild‐type and selenoprotein, will be presented.
Cloning of a Glutathione Transferase Superfamily Gene in Leishmania
Authors: Mckenzie Nerissa , Pitula Joseph , Hearne Jennifer
Published: June 2021

Leishmaniasis is a tropical disease that afflicts approximately 12 million of the world's population. Its causative agent is the parasitic protozoan Leishmania, a member of the Trypanosomatidea family. In contrast to other eukaryotes, members of the Trypanosomatidea family lack a complete heme biosynthetic pathway; therefore, they must acquire heme exogenously. The mechanism of heme scavenging may be accomplished through its coordination with glutathione (GSH) via membrane associated proteins in eicosanoid and glutathione metabolism (MAPEG), members of the glutathione transferase (GST) superfamily. It is known that Macaca fascicularis microsomal prostaglandin E synthase type 2 (mPGES‐2), a MAPEG GST, binds GSH. The enzyme‐glutathione complex then has the potential to form a coordination bond with heme. Previously, our laboratory reported the presence of a suspected GST in L. tarentolae (GST1). Here, we show that a second GST, GST2, also exists in Leishmania. Identification of GST2 was accomplished using genomic searches. PCR amplification of the homolog in L. tarentolae employed primers designed on the basis of the identified gene, LmjF26.1540. We are now expressing the recombinant protein to characterize its activity. Because Leishmania lack a complete heme biosynthetic pathway, the exploitation of its heme dependency is a key target for chemotherapeutic intervention.
High insulin and saturated fatty acid exposure cause mitochondrial dysfunction via distinct mechanisms
Authors: Mora Silvia , Yang Chenjing , Li Xiaoxin , Aye Cho Cho , Diaz Angels , Zorzano Antonio
Published: June 2021

Mitochondrial dysfunction has been associated with insulin resistance, obesity and diabetes. Both hyperinsulinaemia and dyslipidemia are hallmarks of the insulin resistant state. The purpose of this study was to examine the contributions of high insulin and saturated fatty acid exposure on mitochondrial function and gene expression in cultured myocytes. Chronic insulin treatment of myotubes reduced signalling through PI 3‐Kinase/AKT. Insulin‐resistant myocytes exhibited lower mitochondrial membrane potential and ROS production but exhibited ATP levels similar to control cells. Citrate synthase activity was increased in the insulin treated cells. The expression of a number of mitochondrial genes including COX2, COX4, ATP synthase were reduced in the chronic insulin treated cells albeit they were not significant. However, the transcriptional co‐activator PGC1alpha, and uncoupling proteins, UCP2 and UCP3 were significantly reduced in these cells. No changes were detected in Tfam or NRF‐1 transcript levels. Mitofusin2 and Porin protein levels were also not altered by chronic insulin exposure. In contrast, treatment of cells with saturated fatty acid reduced mitochondrial membrane potential, significantly increased ROS production, and increased the mRNA expression of UCP2, UCP3 and ATP synthase. These cells also displayed lower levels PGC1α and PGC1β gene expression compared to controls. Taken together these results suggest that chronic hyperinsulinemia and exposure to saturated fatty acids impair mitochondrial function by different mechanisms.
Decreased apoE within lipoprotein classes in the nephrotic syndrome is due to diluted apoE pool
Authors: Wang Limin , Shearer Gregory C , Budamagunta Madhu S , Voss John C , Kaysen George
Published: June 2021

Hyperlipidemia in nephrotic syndrome (NS) results from decreased clearance of triglyceride rich lipoproteins (TGLs). VLDL and HDL from NS rats have reduced apolipoprotein E (apoE) content despite increased plasma apoE levels. Lipoprotein lipase (LpL) is decreased in both NS and the Nagase Analbuminemic Rat (NAR). However, NAR have nearly normal lipid levels and TGLs clearance. ApoE, a ligand for the VLDL receptor, is depleted from NS VLDL rats, while normal or increased in NAR VLDL suggesting that the difference in VLDL apoE contributes to defective clearance. It is unknown whether decreased apoE was a consequence of decreased binding to VLDL. Plasma apoE was measured by ELISA. Apo E clearance was measured 7 Control, 7 NS and 9 NAR male rats using 125I labeled apoE. Apo E affinity was measured in 6 Control and 5 NS rats using spin labeled E4 binding with electron spin resonance and nonlinear regression. Apo E levels were significantly greater in plasma NS than in NAR and greater in both than in Control. However, VLDL and HDL from NS had significantly less apoE per mole of PL than those isolated from NAR or Control. ApoE clearance was significantly lower in NS than in NAR and Control, entirely accounting for the increased plasma levels of apoE. Binding of apoE did not differ by lipoprotein class or by group. Decreased apoE within lipoprotein classes in the nephrotic syndrome is due to diluted apoE pool. (Supported by the Department of Veteran's Affairs)
Targeted deletion of one or two copies of the Gbeta5 gene has distinct effects on body weight and behavior in mice
Authors: Slepak Vladlen , Wang Qiang , Levay Konstantin , Gavrilova Oksana
Published: June 2021

We describe the phenotypes of mice that lack either one or two copies of the gene encoding G protein beta subunit G beta 5. Gβ5 is unique in that instead of Gγ subunits, it forms obligatory heterodimers with RGS proteins of R7 family (RGS6, RGS7, RGS9 and RGS11). The Gβ5 knockout (KO) animals are leaner than wild type (WT) and are resistant to high fat diet. Surprisingly, the heterozygotes (HET) display the opposite phenotype: they are about 15% heavier than the WT and by 35% heavier than the KO mice. This body weight increase is associated with adiposity and is accompanied by a mild insulin resistance. The second discovered phenotype was the increase in locomotor activity, which was less prevalent in the HET than the KO. The increased activity correlated with a higher level of catecholamines, implicating sympathetic system as a potential mechanism involved in etiology of this phenotype. Analysis of mRNA from hipothalami and prituitary glands of the KO and HET mice detected changes in expression of somatostatin and some other peptide hormones. Thus, we show that both haploid insufficiency and the knockout of Gβ5 can perturb hormone secretion and influence metabolism and behavior.
Structural and evolutionary insights in fasciculation and elongation zeta (FEZ) proteins family
Authors: Alborghetti Marcos Rodrigo , da Silva Furlan Ariane , da Silva Julio Cesar , Sforca Mauricio Luis , Neves Jorge Luiz , Leme Adriana Franco Paes , de Mattos Zeri Ana Carolina , de Torriani Iris Concepcion Linares , Kobarg Jorg
Published: June 2021

The human proteins FEZ1 and FEZ2 are orthologs of UNC‐76 from C. elegans, involved in growth and fasciculation of axons. Our aim is to exploit the molecular evolution of the FEZ protein family with emphasis on vertebrata branch. By the interactome profile of FEZ1 and FEZ2 from H. sapiens and UNC‐76 from C. elegans we observed a conserved pattern of protein‐protein interactions among FEZ1 and UNC‐76 that explain the ability of FEZ1 to rescue defects caused by unc‐76 mutations in nematodes. Furthermore, we characterized the interaction between FEZ1 and SCOCO (short coiled coil protein) by SAXS (Small Angle X‐ray Scattering). This interaction has been previously reported between their orthologs UNC‐76 and UNC‐69 that cooperate in axonal outgrowth. A hetero‐tetrameric state was observed, which consists of two GST‐SCOCO molecules attached to two FEZ1 molecules. By PAGE, SAXS, MS and NMR we defined that FEZ1 dimerizes by disulfide bond. In vivo this dimeric state could be important for kinesin mediated transport along microtubules. Thereby, FEZ1 may be classified as a dimeric and bivalent transport adaptor, essential to axon outgrowth and normal pre‐synaptic organization and transport of cargoes. The aggregation of new interaction partners found for the FEZ2 protein could be interpreted as the acquisition of new molecular functions and may have occurred in the early stages of chordate evolution. Supported by FAPESP, CNPq.
Expression Profile of GT1‐7 Hypothalamic Cell Line Under Exposure Class I Androgen Testosterone Propionate
Authors: Agosto Ibis Milady , Vizcarrondo Giovann , Cruz Raphael , Brito Paul , Garcia Liz , Barreto‐Estrada Jennifer , Roig‐Lopez Jose L.
Published: June 2021

Anabolic Androgens Steroids are synthetic chemicals derivates from testosterone that are currently divided in three major classes. Our research interest is to analyze in vitro expression profile of different classes of androgen analogs using GT1‐7 hypothalamic cell line that will guide us to understand the different responses between anabolic androgens in the Hypothalamic‐Pituitary‐Gonads circuitry. Initially we compared basal profile expression of Testosterone Propionate (TP) and its control vehicle using microarrays. The transcriptome analysis demonstrated data of 1,219 upregulated and 157 as downregulated genes. In order to confirm these results RT‐PCR analysis was used. The genes were divided in three categories up‐regulated know, up‐regulated unknown and down regulated genes. The PCR expression pattern of 10/12 unknown, 7/9 known and 3 out of the down‐regulated genes were confirmed through PCR and gel electrophoresis. This may suggest that the TP may differentially regulate the expression of these unknown genes. These report represent the first functional information about the nature of the unknown genes in which there is no molecular, biological and structural information. Later on, microarray data with other comparisons will be analyzed.

This work was partially supported by the UNE URGREAT‐MBRS‐RISE grant 2R25GM066250‐05A1 and by grant P20 RR016470 from the National Center for Research Resources (NCRR), PR‐ABREE, IDEA/BRIN program a component of the NIH.
Nutrient intakes from restaurants: What We Eat in America, 2007–2008
Authors: Rhodes Donna G , Clemens John C , Adler Meghan E , Moshfegh Alanna J
Published: June 2021

Nationally representative one‐day dietary data from What We Eat in America, NHANES 2007–2008 were analyzed for nutrient intakes from foods consumed from restaurants. The USDA Automated Multiple‐Pass Method was used to collect a 24‐hour recall from 8,529 individuals, aged 2 years and older. During the recall, the source of each food (where it was obtained) was provided by the respondent. Foods eaten from restaurants include both full‐service and fast‐food establishments as well as: bar/tavern; cafeteria, not at school; vending machine; sport, recreation, or entertainment facility; street vendor, vending truck. Restaurant reporters (RR), individuals who reported at least one food/beverage item from a restaurant, comprised 53% of the population. For RR, the contribution of restaurant foods to total daily energy and sodium intakes (mean±SE) was 43±0.7% and 50±0.9%, respectively. From all foods, total daily intake of energy was higher for RR (2242±35.8 kcal) compared to non‐reporters (1875±28.9 kcal). Total daily sodium from all foods was 3623±70.8 mg for RR and 2999±57.9 mg for non‐reporters. Restaurant foods, consumed by a majority of Americans, contribute substantially to both energy and sodium intakes; additional results are to be presented. This study illustrates the importance of considering restaurant foods in both dietary intake research and intervention strategies.

Funding source for this study: ARS, USDA
Energy and nutrient contributions from dairy foods consumed as snacks by 9–18 year old children: Results from analyses of NHANES 2003–2006 dietary data
Authors: Keast Debra R , Auestad Nancy , Fulgoni Victor L , Quann Erin E
Published: June 2021

Dietary Guidelines for Americans recommends three daily servings of low‐fat and fat‐free milk and milk products for people 9 y and older. Average dairy intake by children 9–18 y is 2.2 servings per day. In the U.S., most children consume at least one snack/day, and about 75% have two or more. This study determined the contribution of dairy foods consumed as snacks to energy and nutrient intakes using NHANES 2003–2006 data from children 9–18 y (n=4,371) with a reliable 24‐hr recall interview on the first day. Snacks accounted for 26% of total daily calories. In total, 0.36 cup‐equivalents of milk, flavored milk and cheese were consumed as snacks. These dairy foods contributed 4.8%, 1.1% and 2.7% of snacking calories, respectively. Intake of vitamin D, calcium and potassium (nutrients of public health concern) from these dairy foods was 73%, 45% and 19%, respectively, of the intake from snacks. They also contributed 37%, 35%, 31%, 29%, 25%, 22%, 20%, 13%, 11% of vitamin B12, vitamin A, phosphorus, riboflavin, protein, saturated fat, zinc, magnesium, and sodium intakes, respectively. In conclusion, dairy foods are a nutrient‐rich snack for children 9–18 y. The 0.36 cup‐equivalents of milk, flavored milk and cheese consumed as snacks contributed less than 9% of snacking calories and made notably greater percent contributions to the intake of many essential nutrients. (Supported by Dairy Research Institute)
Risk Factors for Childhood Obesity in Head Start and Early Head Start Children
Authors: Copeland Beverly , Johnson Allan Alexander
Published: June 2021

With an estimated 14.2% of U.S. children aged 2–5 years being obese, the purpose of this study was to investigate the risk factors that influence childhood overweight and obesity in Head Start children and their families. A cross‐sectional descriptive study was conducted. Participants in the study were 195 Head Start children between the ages of two to five years old, and their caregivers. The following data were collected: weight and height [used to calculate Body Mass Index (BMI)], eating practices, physical activity levels, perceptions of overweight/obesity of parents/caregivers, and household socio‐economic status. The relationships of the risk factors to childhood obesity were analyzed using chi‐square and t‐tests. A significant relationship was found between doctors and health professionals’ weight advice (χ2 statistic = 17.494, p = 0.001), caregivers’ perceptions of their children's weight (χ2 statistic = 22.4, p = 0.000) and, caregiver educational attainment and child BMI status (χ2 statistic = 8.016, p = 0.046). Both doctors and caregivers were more likely to misclassify overweight/obese children as normal. Also, caregivers perceived their own overweight/obese health condition favorably. Intakes of vitamin A and calcium were significantly higher in the overweight/obese children. No other significant differences were found between children of normal BMI status and overweight/obese children.
Childhood overweight and obesity models with high correlated food consumption data
Authors: Méndez-Gómez-Humarán Ignacio , Méndez-Ramírez Ignacio , Shamah-Levy Teresa , Moreno-Macías Hortensia , Murata Chiharu
Published: June 2021

Objective

Discus the use of cluster analysis in statistical models for association of overweight and obesity (OW+O) with high correlated food consumption variables.

Methods

We compare regression models for association of OW+O with nutrient consumption (energy, carbohydrates, lipids, fiber and sodium). A sample of 8,367 children with food and beverages consumption records, separated in out of home and global consumption. Ward clustering method was used to group consumption patterns based on standardized averages by state. A simple analysis of variance was used to model the association.

Results

Linear models fail to find significant associations between consumption patterns and OW+O due to multicolliniarity. Cluster analysis is useful to establish grouped consumption patterns, we selected 4 consumption groups. Analysis of variance and Tukey‐Kramer test shows a significant higher prevalence of OW+O in cluster 2 with respect to cluster 4.

Conclusion

Nutrient consumption patterns and other collinear data can be used integrally with cluster analysis for group patterns as an explanatory variable in statistical models.
Human postprandial blood concentrations of leucine and insulin increase phosphorylation of mTOR in C2C12 myoblasts
Authors: Walker Dillon , Drummond Micah , Rasmussen Blake
Published: June 2021

Leucine (Leu) and insulin (Ins) stimulate growth primarily through activation of the mammalian target of rapamycin (mTOR) pathway. Most cell culture studies use supraphysiological concentrations of Leu and Ins when examining their effect on muscle cells. Our aim was to determine whether human postprandial concentrations of Leu and Ins could enhance mTOR activation in muscle cells. C2C12 myoblasts were grown in growth media for 2 d. Media was replaced with low serum media for 4 d to induce fusion. Myotubes were serum starved for 4 h then nutrient starved for 30 min. Leu (0, 0.25, 0.5, 1, 2, or 5mM) or Ins (0, 0.03, 1, 10, 50, and 100nM) were applied to cells for 30 min. Cells were then harvested for protein extraction. Western blot analysis was used to access phosphorylation status of mTORser2448. Leu concentrations between 0.25 and 5mM resulted in a 3.5 to 6.1 fold increase in the phosphorylation of mTOR over control after 30 min. Ins concentrations between 0.03 and 100nM resulted in a 1.8 to 7.1 fold increase in the phosphorylation of mTOR over control after 30 min. Postprandial concentrations of Leu (~1 mM) and Ins phosphorylated mTOR similarly to supraphysiological concentrations. We conclude that human postprandial concentrations of Leu and Ins increase mTOR activation and should be used in cell culture studies to examine human biological responses.

Supported by NIAMS R01 AR049877
Amino acid metabolism during endotoxemia in fed pigs
Authors: Price K.L. , Ramirez E.M. , Lee H. , van Eyk G.R. , Hanigan M.D. , Escobar J.
Published: June 2021

Individual plasma amino acid (AA) changes were quantified in endotoxemic fed pigs to calculate their catabolic and appearance rates. Pigs (19.1 ± 0.4 kg BW) were surgically fitted with an indwelling jugular catheter, allowed to recover, food‐deprived overnight, fed (t = −2 h), and treated with either sterile saline (n=16) or 10 μg/kg BW of LPS (n=15) at t = 0 h. Multiple blood samples were collected from −2 to 24 h after LPS treatment. Area under the curve (AUC) was calculated for individual AA from t = − 2 h to the first time when concentrations were equivalent for saline and LPS treatments, and from there to 24 h. Initially Lys, Met, Phe, His, Arg, and Thr AUC were less (P<0.03) in LPS pigs compared to saline. Then, Lys, Met, and Phe AUC in LPS pigs exceeded (P<0.01), His tended to be higher (P=0.07), but Arg and Thr were not different (P=0.13) from saline controls. For the entire study, AUC for Ile, Leu, Val, Gln, Orn, Trp, and Tyr in LPS pigs were reduced (P<0.04) while Ala and Tau (P<0.001) were greater in LPS pigs compared to controls. Initially, Glu AUC was not different (P=0.91) but subsequently became reduced (P<0.01) in LPS pigs compared to saline controls. In LPS pigs, calculated AA catabolism ranged from −0.04 to −1.34 μmole·kg BW−1·h−1 and plasma appearance ranged from +0.03 to +0.74 μmole·kg BW−1·h−1. Our results support the need for AA supplementation of critically ill patients. College of Agriculture and Life Sciences
Analysis of extracellular levels of serotonin in rat amygdala after oral administration of large amounts of tryptophan
Authors: Yoshizawa Fumiaki , Honda Manami , Sugahara Kunio
Published: June 2021

Serotonin (5HT) is an important neurotransmitter known to affect many behaviors. The synthesis of 5HT in the brain is dependent on the availability of tryptophan (Trp) from plasma. Therefore, oral administration of Trp affects 5HT synthesis in the brain. We focused on the amygdala, a brain structure central in the generation of both normal and pathological emotional behavior. The aim of this work was to investigate the effects of oral administration of large amounts of Trp on the extracellular levels of 5HT and its metabolite 5‐hydroxyindoleaceticacid (5HIAA) in the amygdala. The overnight fasted rats were administered Trp at concentrations ranging from 18 to 144 mg/100g BW by oral gavage. The lowest concentration of Trp employed is equivalent to that consumed in a 24‐h period by rats. Extracellular levels of 5HT and 5HIAA in rat amygdala were measured with in vivo microdialysis technique. During the observation period, no changes were observed in the levels of 5HT in all treatment groups. In contrast, the levels of 5HIAA started to increase from the basal level at one hour after oral administration of Trp, irrespective of the doses of Trp. The maximum levels of 5HIAA were almost the same among all Trp administered groups, but the higher doses of Trp had a more prolonged effect on the levels of 5HIAA. These results suggested that oral administration of large amounts of Trp induced an increase in neuronal activity in amygdala.
Gender influences Metabolic Syndrome Criteria
Authors: Aguilar David , Barona Jacqueline , Dugan Christine E , Andersen Catherine J , Blesso Christopher N , Fernandez Maria Luz
Published: June 2021

Metabolic syndrome (MetS) parameters were evaluated in sixty six participants (24 women and 42 men) to determine whether gender influences the inclusion criteria of MetS [waist circumference > 88 cm in women and > 102 cm in men; HDL cholesterol (HDL‐C) < 50 and < 40 mg/dL in women and men, respectively; plasma triglycerides (TG) > 150 mg/dL, blood pressure (BP) > 130/85 mm Hg and plasma glucose > 100 mg/dL]. The most prominent criteria in men for MetS classification was high systolic BP (80%), high TG (66%) and low HDL (38%). In women, the criteria were high WC (100%), low HDL (42%) and high plasma glucose (38%) Comparisons between gender indicated that women had higher HDL‐C (p< 0.05) while men had higher plasma TG, and systolic blood pressure (p< 0.05). In women, High WC was correlated with low HDL‐C (r = −0.520, p< 0.01) and high TG was correlated with elevated blood glucose (r= 0.406, p< 0.05). In men, high TG were correlated with low HDL‐C (r‐0.594, p< 0.05). These results indicate that WC, the most common inclusion criteria for women is associated with dysregulation of plasma lipids and glucose metabolism as a result of increased fat accumulation in the abdominal area. While in men the elevated plasma TG are associated with low HDL suggesting that lipid abnormalities that place individuals at MetS classification are more common in this male population.
Effect of ground beef fatty acid composition on atherosclerotic cardiovascular disease risk factors in healthy men
Authors: Wu Xiuzhi , Cao Xiaojuan , Clifford Andrew J. , Smith Stephen B. , Crouse Stephen F. , Walzem Rosemary L.
Published: June 2021

Dietary fatty acids reportedly alter atherosclerotic cardiovascular disease (ASCVD) risk. Oleic acid, the major monounsaturated fatty acid (MUFA) in beef, may improve blood lipids (AJCN 70:1009, 1999). We sought to compare the effects of MUFA:SAT ratios in ground beef patties with a fixed total fat content of 24 g fat/100 g patty in 25 healthy men. Test beef patty MUFA:SAT was either 1.10 (HI) or 0.71 (LO). Subjects consumed 5 patties per week in a random test‐retest design lasting 5 weeks each separated by 4‐week wash‐out period. We measured metabolic indices and HDL functionality immediately before and at the end of each test. Increased beef consumption per se, and beef MUFA:SAT had no effect on circulating homocysteine, adipokines, or HDL3 apolipoprotein composition. Beef patty MUFA:SAT had no effect, while beef consumption per se increased total HDL (p<0.001), HDL3 (p<0.0001) and atheroprotective HDL3 sphingosine‐1‐phophate (S1P) (p<0.05). Independent of MUFA:SAT, beef consumption also improved insulin sensitivity as judged by reduction in HOMA scores (p<0.05). Interestingly, beef consumption per se caused a decrease in PON1 activity per HDL (p<0.05). We conclude that increased beef consumption improved indices of HDL functionality and insulin sensitivity independent of fatty acid composition. “Funded in part by The Beef Checkoff through the National Cattlemen's Beef Association”
The Impact of Selective High Fat Diets on Altered Thyroid Animal Model
Authors: White Venus Welch , Dawkins Norma L , Graham Thomas , Pace Ralphenia D
Published: June 2021

The association of adverse health with higher fat diets has long been recognized; however due to a lack of research which incorporates high fat, thyroid function and metabolic syndrome, the pathogenesis of a high fat diet impact remains poorly understood. The objective of this study was to conduct a comparative analysis of the physiological differences between rats fed various concentrations of saturated and unsaturated fat diets in a normal and a thyroid compromised rat. Adult male Sprague Dawley rats (n=100) were exposed to one control or four test diets; Control 12% Fat, a 25% saturated and unsaturated, and a 35% saturated and unsaturated, respectively. Each diet group contained ten normal and ten altered thyroid animals. A chemical induced thyroidectomy was obtained through the addition of .05% propylthioracil (PTU) in drinking water. The study was conducted over a period of 8 weeks. The body weights of the normal animals were significantly higher than in the altered thyroid groups. Metabolic markers, glycosylated hemoglobin (HbA1c) and urinary glucose values remained normal in all experimental groups both pre‐ and post treatment. This study may provide a foundation for development in an experimental model for future studies which evaluate the impact of a high fat diet, thyroid and metabolic function. This research was supported by George Washington Carver Experimental Station, Tuskegee University.

Grant Funding Source : ASN