bluuebunny/crossref_metadata_2025 huggingface dataset:
U.S. Trends in dietary variety and its association with BMI and micronutrient intakes
Authors: Ebner Rachel Eve , Burke Aoife P , Kranz Sibylle , Boushey Carol J , Roberts Susan B , McCrory Megan A
Published: June 2021

One proposed contributor to excess energy intake is dietary variety, particularly energy‐dense variety (McCrory et al 1999). Using national survey data, we examined the potential role of dietary variety in the obesity epidemic and relationships among variety and micronutrient intake. Usual dietary intake data from the Continuing Survey of Food Intakes by Individuals (CSFII) 1989–91 and 1994–96 were coded and six dietary variety scores were calculated as described previously (Roberts et al 2005). We included adults aged 21–60 y, and excluded individuals with implausible energy intake reports (Huang et al 2005) and BMI<17 kg/m2. Results showed all types of dietary variety increased from 1989–91 to 1994–96 (p≤.025), except for food group variety which remained constant. In both surveys, energy‐dense variety was higher and energy‐weak variety was lower with higher BMI (p≤.05). Micronutrient dense variety was positively associated with mean micronutrient intake (%EAR) in both surveys (p≤0.001), whereas energy‐dense variety was only weakly associated with greater micronutrient intake in 1989–91 and not associated in 1994–96. Increasing energy‐dense variety over time may lead to weight gain with minimal contribution to micronutrient intake.

Grant Funding Source : n/a
Potato consumption among children and adolescents, ages 2 to 18, in the U.S
Authors: Storey Maureen L , Anderson Patricia A
Published: June 2021

Potatoes are an important and affordable source of potassium (K) and dietary fiber (DF). We examined potato consumption using recent data from the 2005–2006 and 2007–2008 National Health and Nutrition Examination Survey for children and teens ages 2–18 y. Appropriate survey weights were used to calculate average consumption of white potatoes, including baked, boiled, roasted, stewed, stuffed, mashed, French fried, potatoes with sauce, hash browns, homefries, potato skins and potato salad. Among males, average calories (kcal) from white potatoes increased from 45 kcal in early childhood to 79.5 kcal among teens. On average, girls 2–4 consumed 46.4 kcal and females 14–18 consumed 61.5 kcal from white potatoes. Males 2–4, 5–8, 9–13, and 14–18y consumed an average of 29.2, 34.6, 39.7, and 54.8 kcal from French fried potatoes, respectively. Females 2–4, 5–8, 9–13, and 14–18y consumed about 34.4, 48.3, 45.3, and 34.1 kcal from French fried potatoes, respectively. We also examined consumption of white potatoes and French fried potatoes from school cafeterias for children 5–18y. Less than 1 percent of total kcal came from white potatoes and French fried potatoes from school cafeterias. A 10‐strip (115 kcal) serving of oven‐baked potato fries provides 325 mg K, 1.6 g DF and 0.7 g saturated fat. Encouraging consumption of potatoes may be an effective way to increase K and DF among children and teens.
Reduced Sampling Schedules for Calculation of an Insulin Sensitivity Index from the Liquid Meal Tolerance Test
Authors: Maki Kevin C , Gower Barbara A. , Rains Tia M. , Schild Arianne
Published: June 2021

Previous results from our laboratory indicate the Matsuda insulin sensitivity index (MISI) calculated from a liquid meal tolerance test (LMTT) correlates well with the minimal model insulin sensitivity index (SI). The present analysis evaluated the influence of reduced LMTT sampling schedules on the relationship between MISI and SI. Subjects included 38 men and 31 women, mean±SEM age 35.1±1.0 yr and BMI 32.5±0.5 kg/m2. For the LMTT, subjects consumed a liquid meal (Carnation Instant Breakfast® and whole milk) providing 7 kcal/kg (24% fat, 59% carbohydrate, and 17% protein). SI was calculated from the 30‐ sample, insulin‐modified intravenous glucose tolerance test (MINMOD, v3). The Pearson correlation coefficient between SI and the MISI using values at 0, 30, 60, 90, 120 min was 0.519, p<0.0001. Correlation coefficients for selected reduced sampling schedules were: 0, 60, 120 min (r=0.493); 0, 120 min (r=0.534); 0, 30, 120 min (r=0.476); 0, 30, 60 min (r=0.450), 0, 60 min (r=0.461; all comparisons p<0.001). Correlation coefficients for the full and reduced schedule MISI values were r=0.953 for the 0, 60, 120 min and r=0.909 for the 0, 120 min schedules, respectively (both p≤0.0001). These results suggest that the MISI calculated from reduced sampling schedules (0, 60, 120 min and 0, 120 min) may be useful for application in population studies.
Effects of apple cider vinegar on postprandial blood glucose and satiety
Authors: Bollinger Laura , Holden Jocelyn , Chezem Jo Carol
Published: June 2021

The study objective was to describe changes in postprandial blood glucose and satiety following ingestion of 30 ml apple cider vinegar. In a crossover design, 15 healthy adults consumed a breakfast of cooked farina cereal containing 50 grams of available carbohydrate, served with and without 30 ml apple cider vinegar, in random order following an overnight fast. Blood glucose and satiety were assessed at minutes 0, 15, 30, 45, 60, 90 and 120. There were no significant differences in blood glucose levels or glucose incremental areas under the curve (IAUCs) between the two conditions. Satiety levels at 15 min and satiety IAUC at 0–15 min were significantly higher (p =.038 and p =.038, respectively) with vinegar. These results suggest ingestion of apple cider vinegar at mealtime has no effect on glycemic response and only short‐term influence on satiety in healthy adults.
Complementary foods for appetite suppression
Authors: Sussman Elizabeth , Johnston Carol S
Published: June 2021

New diet strategies are needed to aid with weight loss and adherence to energy‐restricted diets. This study examined the appetite suppression and antiglycemic effects of two novel foods: algae and gelatin. In a double‐blind, randomized, crossover study, 15 healthy individuals (7 M, 8 F; 28±7y, BMI 26.1±5.6kg/m2) consumed an isocaloric breakfast meal under three treatments separated by 1–2 wk: control (buttered bagel, juice); algae (algae [4g protein] enriched butter, bagel, juice); and gelatin (gelatin [4g protein] enriched butter, bagel, juice). Five blood samples (0, 30, 60, 90, 120 min postprandial) were collected and analyzed for glucose. Hunger was assessed using a 100mm visual analog scale. Food and beverage consumption for the remainder of the day was recorded. Neither algae nor gelatin altered postprandial glycemia or perceptions of hunger up to 2 h post‐ingestion. However, there was a marked decrease (300–400 kcal) in subsequent 24 h energy consumption in the gelatin group when compared to the algae (p=0.01) or control (p=0.07) groups. These data suggest that gelatin ingestion may be associated with appetite suppression over a 24 h period. Supported by ASU Graduate and Professional Student Association

Grant Funding Source: Graduate and Professional Student Association, Arizona State University
Genotypic differences impact serum and hepatic lipids in mice lacking carotenoid cleavage enzymes
Authors: Elsen Amy Christine , Ford Nikki A. , Erdman John W.
Published: June 2021

Adult mice lacking the β‐carotene central cleavage enzyme, carotene‐15,15′‐monoxygenase (CMO‐I), have been reported by Hessel and colleges to have altered lipid metabolism, but little is known about the lipid content in carotene‐9′10′‐monooxygenase II knock‐out (CMO‐II KO) mice or whether tomato powder or lycopene alters lipid deposition in either genotype. Serum and hepatic lipid content was measured in female CMO‐I KO, CMO‐II KO and wild type (C57BL/6Jx129x1/SvJ) mice fed AIN‐93G based diets: 10% tomato powder diet, 100 mg lycopene/kg beadlet diet or placebo beadlet diet for 4 days. Hepatic lipid content was significantly greater in CMO‐I KO mice and CMO‐II KO mice relative to wild‐type mice, independent of dietary intervention (p <0.005). H&E staining revealed that 25% of CMO‐I KO adult mice have minimal hepatic lipidosis. The diets in this study negligibly impacted lipid content. Specifically, hepatic cholesterol levels were elevated in CMO‐II KO mice when fed lycopene beadlet diet compared to placebo beadlet diet (p <0.05) and decreased in mice when fed tomato powder compared to AIN‐93 G diet (p<0.05). This data suggests that a lack of CMO‐I or CMO‐II alters serum and hepatic lipids but short term feeding of carotenoid diets has minimal impact on lipid deposition in these mice.

Grant Funding Source : NIH grant PHS‐RO1 CA125384
Biomarker erythrocyte copper chaperone for superoxide dismutase (CCS) is higher following marginal copper deficiency
Authors: Prohaska Joseph R , Lassi Katie , Broderius Margaret
Published: June 2021

There is a critical need to identify an accurate copper biomarker to diagnose and treat adult onset copper deficiency. Prevalence is rising due to secondary impacts of antagonists such as zinc and popularity of bariatric surgery. Marginal copper deficiency (CuM) and iron deficiency (FeD) were studied in Sprague Dawley rat and Swiss Webster mouse models using modified AIN‐93G diets. Red blood cell (RBC) superoxide dismutase (Sod1) and plasma ceruloplasmin (Cp) protein were found to be altered by both FeD and copper deficiency (CuD), while CCS and CCS/Sod1 ratio were found only to be altered in CuD rats; and importantly, after only 1 week of treatment in post weanling males. RBC CCS levels were highly negatively correlated, r = −0.91, with liver copper in CuD, CuM and copper adequate (CuA) rats. Post weanling CuD male mice reared in plastic cages for 5 weeks had no significant reduction in liver copper, plasma Cp protein, or RBC Sod1 compared to CuA mice but CuD mice displayed 2‐fold higher RBC CCS. CuD adult male mice with no significant changes in Cp activity and protein after 5 weeks of dietary treatment displayed augmented RBC CCS. Additional research is needed to establish that erythrocyte CCS is a suitable copper biomarker for humans but RBC CCS appears to be a robust marker for marginal copper deficiency in rodent models.

Supported by the International Copper Association and USDA NIFA 2006‐35200‐17378.
The effects of raw kernel and peanut butter on glucose homeostasis in glucose‐intolerant obese women
Authors: Costa Neuza MB , Reis Caio EG , Ribeiro Daniela N , Totaro A S , Tonazio M C , Bressan Josefina , Mattes Richard D , Alfenas Rita CG
Published: June 2021

The study aimed to investigate whether unprocessed (raw kernel) or processed peanut (butter) exert different effects on glucose homeostasis. Fifteen glucose‐intolerant obese women, in a randomized crossover clinical study, received a breakfast containing 75 g available carbohydrate, 42.5 g raw peanut (RP), peanut butter (PB) or no peanut ‐ Control meal. Blood sampling was performed at −10, 15, 45, 60, 90, 120, 180, 240, 265, 295, 310, 340, 370, 430 and 490 minutes after the breakfast and after a lunch providing 75 g available carbohydrate at 240 min for the analysis of blood glucose, insulin, free fatty acids (FFA) and GLP‐1. Data were analyzed by ANOVA‐RM with the Bonferroni correction and ANOVA followed by Tukey test (p<0.05). The postprandial response (0–4h) of FFA and the glycemic response (4–8h) were lower in PB than the Control group. Higher insulin concentrations were observed 45 min after RP and at 120 and 370 min after PB, compared with the Control. Both peanut groups (RP and PB) had higher postprandial responses (0–8h) of GLP‐1 than the Control. The intake of 42.5 g peanut butter in the breakfast reduced the concentrations of FFA (0–4h) and postprandial glycemia (4–8h) even after the second meal intake. It is hypothesized that production of peanut butter disrupts cell walls, releasing the lipid content, which, in turn, reduces the gastric emptying time and thereby lower the glycemic response. Additionally, the intake of monounsaturated fatty acids provided by the peanuts may raise GLP‐1 secretion, improving insulin sensitivity and lowering blood glucose concentrations and the risk of type‐2 diabetes.

Supported by Peanut Institute.
Maternal Height and child growth: intergenerational perspectives
Authors: Addo O. Yaw , Stein Aryeh D , Horta Bernardo L , Martorell Reynaldo ,   the COHORTS Group
Published: June 2021

We examined the association between maternal height and offspring birth weight and child growth in height using 6,853 mother‐child pairs from prospective birth cohort studies in 5 low‐to‐middle income countries (Brazil, Guatemala, India, Philippines and South Africa). We modeled conditional heights as height gains given prior heights and birth weight for the windows of birth, birth‐2y, 2–4y, and 4y‐adulthood.

After adjusting for maternal SES, schooling and child sex, maternal height was linearly associated with child growth in both pooled and site stratified analyses. In pooled analysis, one SD unit increase in maternal height was associated with 0.16, 0.24, 0.17 and 0.32 SD units of offspring birth weight and conditional length at 2y; 4y, and adulthood windows respectively (each p<0.0001). Associations were consistent across the five sites.

Even though offspring size is an outcome of genetic and environmental factors such as nutrition, maternal height appears to have comparable strengths of association with birth weight, conditional height gain for birth‐2y and 2–4y. This association is however, slightly higher for the 4y‐adulthood window of growth. Maternal height is significantly associated with child growth throughout the life course.

COHORTS: Consortium of Health Oriented Research in Transitioning Societies

Grant Funding Source : Wellcome Trust, Bill and Melinda Gates Foundation
Effects of chronic methylphenidate treatment on the reinforcing strength of cocaine in rhesus monkeys
Authors: Czoty Paul W. , Martelle Susan E. , Gould Robert W. , Nader Michael A.
Published: June 2021

Drugs that indirectly stimulate dopamine receptors have been proposed as candidates for pharmacotherapies for stimulant addiction. These studies examined the effects of chronic methylphenidate treatment (MPD; 0.003–0.056 mg/kg/hr, i.v.) on cocaine self‐administration in 3 rhesus monkeys. In an attempt to more closely resemble clinical conditions of cocaine use and medication treatment, during chronic MPD treatment, cocaine self‐administration was examined once weekly in evening sessions under a progressive‐ratio schedule. Food‐reinforced responding was examined each morning under a fixed‐ratio schedule to assess some potential “side‐effects” of MPD treatment. Importantly, as in a treatment setting, decisions regarding dosing were made for individual subjects based on that monkey's response to MPD. In contrast to data obtained with this procedure using d‐amphetamine as a treatment agent (Czoty et al., Neuropsychopharmacology 36:539, 2011), MPD did not produced sustained decreases in cocaine self‐administration up to doses that disrupted food‐maintained responding and/or incerased agitated/aggressive behavior. The data suggest that chronic treatment with MPD under this regimen would not be an effective trteatment for cocaine addiction and, in combination with previous results, indicate that an amphetamine‐like drug may be more effective. Support: DA 06634.
Assessment of the abused inhalant toluene on intracranial self‐stimulation in a dynamic exposure model of inhalant delivery
Authors: Tracy Matthew E , Younkin Jason , Shelton Keith L
Published: June 2021

The intracranial self‐stimulation (ICSS) paradigm was used to examine the rewarding effects of the abused solvent toluene. Bipolar electrodes were surgically implanted into the medial forebrain bundle of seven C57BL6/J mice. After recovery the mice were trained to respond on one of two levers for self‐stimulation for 1 min at each of the 10 descending frequencies from 158–56 Hz. This 10 min response component was repeated three times within each daily session. Two 20 min timeouts were programmed following the 1st and 2nd components. Toluene was delivered from the end of the 2nd component to the end of the session. As a positive control the ability of 3 and 17 mg/kg cocaine to alter ICSS responding was also examined. Exposure to 1000 and 2000 PPM toluene significantly increased ICSS responding. The 3000 and 4000 PPM toluene concentrations produced a biphasic effect on responding whereas 6000 PPM significantly decreased responding. Both doses of cocaine significantly enhanced ICSS responding. These data suggest that toluene has reward enhancing actions and that ICSS can be adapted to study the rewarding effects of inhalants. Supported by NIDA grant RO1‐DA020553.
Endothelium‐dependent and independent effects of isoquercitrin in rat mesenteric bed involve nitric oxide production and direct activation of ATP‐sensitive K+ channels
Authors: Junior Arquimedes Gasparotto , Piornedo Rene dos Reis , Da Silva Santos Jose Eduardo , Assreuy Jamil
Published: June 2021

The vascular effect of isoquercitrin (ISQ), a flavonoid with putative cardioprotective effects, was investigated in perfused mesenteric vascular bed removed from naïve Wistar rats (females, 3–4 months). The perfusion pressure (PP) was measured under continuous flux of physiological saline solution (PSS, 4 ml/min) containing phenylephrine (10 μM). In endothelium‐intact tissue, PP was reduced by ISQ around 13, 33 and 60% at doses of 0.1, 0.3 and 1 μmol, respectively. Chemical removal of endothelium by sodium deoxycholate, as well as L‐NAME, an inhibitor of nitric oxide (NO) synthase, and the K+ channel blockers tetraethylammonium or iberiotoxin, partially avoided (~40%) the effects of 1 μmol of ISQ. The ATP‐sensitive K+ channel blocker glibenclamide (GLB, 10 μM) vanished the effects of ISQ at 0.1 and 0.3 μmol, but was ineffective against 1 μmol. However, infusion of GLB + L‐NAME, or high K+ (40 mM) solution, fully prevented the effects of ISQ. These results suggest that, in addition to previously showed angiotensin‐converting enzyme inhibition, the vascular effects of ISQ includes direct opening of ATP‐sensitive K+ channels and increased production of NO in resistance arteries.

Research support: DEGPP/UNIPAR and CNPq/Brazil.
Endoplasmic Reticulum (ER) Stress inhibition via S‐methyl‐N, N‐diethylthiocarbamate sulfoxide (DETC‐MeSO) in Focal Cerebral Artery Occlusion in Rat
Authors: MohammadGharibani Payam , Modi Jigar , Menzi Janet , Prentice Howard , Tao Rui , Wu Jang Yen
Published: June 2021

ER functions can be disturbed after excitotoxicity which leads to changes in calcium homeostasis. One approach for protecting neurons from excitotoxic damage is blocking of NMDA receptors with specific antagonists. We investigated the neuroprotective effect of DETC‐MeSO, a partial antagonist of NMDA receptors in the rat stroke model. Focal cerebral ischemia was induced by occlusion of the left middle cerebral artery for 2 hours. DETC‐MeSO (5.6 mg/kg) was administered subcutaneously for 4 days, then rats were sacrificed and infarct size in the left hemisphere was measured by TTC staining. Western Blotting on the core and the penumbra tissue of both hemispheres was done for analysis of the expression of key proteins involved in apoptosis (Bax, Bcl‐2), heat shock proteins (HSP27, HSP70), GRP78, ER stress markers (IRE1, PERK and ATF6 pathways) and p‐AKT. TTC staining showed that DETC‐MeSO can decrease the lesion volume size in the left hemisphere. Up‐regulation of Bcl‐2 to Bax ratio was seen in the core and the penumbra of treatment group. HSP27 and p‐AKT protein expression were increased in the core and the penumbra of treated group, while HSP70 and GRP78 protein expression showed no changes. Our data indicated that the administration of DETC‐MeSO can attenuate ER stress, mostly via IRE1 pathway mediated by down‐regulation of IRE1α, Ask1, JNK and GADD34 proteins and up‐regulation of Bcl‐2 protein.

Grant Funding Source: Florida Department of Health
Modulation of S‐nitrosation by thioredoxin regulates endothelial permeability
Authors: Mujica Patricio E. , González Francisco G. , Durán Walter N.
Published: June 2021

Protein S‐nitrosation has emerged recently as a mechanism to regulate cell function. We tested the hypothesis that cytosolic thioredoxin (Trx1) – thioredoxin reductase (TrxR1) system contributes to the control of endothelial permeability. In human microvascular endothelial cells (HMVEC) of dermal origin, we used PAF‐stimulated hyperpermeability and hypoxia‐reoxygenation as test models. Inhibition of Trx1/TrxR1 elevated baseline permeability, and allowed further increase in permeability by PAF. PAF increased global S‐nitrosation as reported by anti Snitroso cysteine antibody. Double depletion of Trx1/TrxR1 increased baseline as well as PAF‐stimulated and hypoxia‐induced global S‐nitrosation. We observed, by immunofluorescence microscopy and immunoprecipitation, the association between Trx1 and eNOS. Both enzymes associate and colocalize in the cytosol suggesting that Trx1 contributes to regulation of eNOS activity. We conclude that interactions between eNOS and the Trx1/TrxR1 system contribute to activation and inactivation of hyperpermeability. (Supported by NIH 5RO1 HL070634 and 5RO1 HL088479).
Histological characteristics of mouse diaphragm lymphatics and their functional significance
Authors: Wang Wei , Zawieja David C. , Negrini Daniela
Published: June 2021

Morphology and distribution of lymphatics in the mouse diaphragm were investigated using LYVE‐1, a lymphatic endothelial marker.

Results

1. Lymphatic networks were observed in the muscular (MP) and tendinous portions (TP) of the diaphragm. The density of small lymphatics (Φ ≤ 20 μm) in MP was much higher than in TP, while it was opposite for large (Φ ≥ 30 μm) lymphatics. 2. On the pleural side (PlS) most LYVE+ structures were tubular but scanty stomata. 3. On the peritoneal side (PeS), besides these same structures, there were LYVE+ membranous tissues that were ladder/lacy‐like structure with many stomata. 4. The same LYVE+ structure with stomata could be observed from both TP PlS and TP PeS. The TP PeS stomata were larger, rounder, and more open than the other side. This indicates that diaphragm lymph is mainly formed in MP and that diaphragmatic contraction may be a major force for lymph flow. Thus respiration may control diaphragmatic lymph flow. The stomata configuration suggests gated communication between the peritoneal and pleural cavities. The ladder/lacy‐like membranous structure may hold some still unclear cell components and provide an unveiled function of the diaphragm lymphatics. These findings provide evidence that the diaphragmatic lymphatic system may have special clinical significance in dialysis, metastasis, infection and nutrition. NIH HL70308, HL094269, & HL80526.
Susceptibility of the isolated female rat heart to ischemia‐induced ventricular fibrillation varies with estrous cycle stage
Authors: Clements-Jewery Hugh , Hatcher A.S.
Published: June 2021

The vast majority of studies employing the isolated perfused rat heart model to study ischemic arrhythmias have used male rats only. The objective of this study was to determine the variation in susceptibility to ischemia‐induced ventricular fibrillation (VF) in isolated female rat hearts with the changing endogenous reproductive hormonal environment associated with the estrous cycle.

Hearts were isolated from female rats under anesthesia and perfused with 3 mM K+ Krebs solution. Experiments were grouped according to estrous cycle stage that was determined by prior vaginal lavage (n=9–13 per group). A group of male rats was used as the control. Regional ischemia was induced by coronary ligation and maintained for 30 min. The incidence of VF was determined from the ECG.

The incidence of VF in male hearts was 100%, while the incidence of VF in female hearts was also high but varied with stage of the estrous cycle (proestrus 89%, diestrus 78%, metestrus 100%, estrus 69%; p>0.05). There was no difference between groups in time to onset of VF or ischemic zone size (range 40–44% of total ventricular weight).

In conclusion, the susceptibility of isolated female rat hearts to ischemic VF is comparable to that of male rat hearts. However, the variation in VF susceptibility in female rat hearts associated with the different stages of the estrous cycle may affect the statistical power of a study.

Supported by a WVSOM intramural grant.
Estrogen regulation of monocyte and endothelial cell adhesion
Authors: Czapp Nikole , McGuinness Michael P
Published: June 2021

Estrogens may regulate cell adhesion molecules and alter monocyte binding to endothelial cells. These actions are mediated by receptors present in the nucleus and/or on the plasma membrane. To determine if estrogen receptors are expressed on the plasma membrane of a monocyte cell line, THP‐1 cells, were incubated in primary antibody to either ERα, ERβ, actin, or no primary antibody. A secondary antibody conjugated to metallic beads was used to isolate cells. A significantly greater number of cells were isolated with antibodies to ERα or ERβ than controls. To determine if estrogen alters levels of cell adhesion molecules HUVEC cells and THP‐1 cells were treated with 17 beta □estradiol (0–600nM) for 6, 12 and 24 hours. Western Blots were performed to measure the levels of ICAM‐1, VE‐Cad, N‐Cad, and Alpha‐L integrin. No significant differences were measured. To measure the effect of estradiol on adherence of THP‐1 cells to HUVEC cells, cell lines were treated with 200nM estradiol for 24 hours prior to co‐culture. The number of THP‐1 cells adhering to HUVECs was determined after 15 minutes of co‐culture. When HUVEC or THP‐1 were treated with 17beta estradiol there was a 2 fold decrease in the number of THP‐1cells adhering. When both HUVEC and THP‐1 cells were treated there was a 5 fold decrease in adhering THP‐1. Thus, estrogen is able to down‐regulate monocyte adhesion to endothelial cells. However, the mechanism remains unclear.
EARLY MICROVESSEL LOSS IN THE METABOLIC SYNDROME
Authors: Goodwill Adam G. , Butcher Joshua , Brock Robert , Olfert I. Mark , Frisbee Jefferson C
Published: June 2021

The metabolic syndrome (MS) is an integrated disorder reflecting development of multiple risk factors for a poor cardiovascular outcome, including obesity, insulin resistance and genesis of pro‐inflammatory/ pro‐oxidant environment. The obese Zucker rat (OZR) represents an excellent model of MS, with impairments to vascular reactivity due to low NO bioavailability and altered arachidonic acid metabolism and a parallel reduction to skeletal muscle microvessel density (MVD, rarefaction); key contributors to poor perfusion outcomes. While the full extent of rarefaction is well predicted by the loss of NO, we have determined that an early pulse of rarefaction develops in OZR which precedes any loss in NO bioavailability, and without which the NO‐dependent loss in MVD is attenuated. Subsequent experiments suggest that the strongest predictors of early rarefaction are shifts in vascular inflammation (TNF‐α), increased production of thromboxane A2 (TxA2) and venular leukocyte adhesion. Current experiments have supported this conceptual model, as targeted interventions have abolished the early rarefaction, with initial candidate proteomic targets being the ratio of thrombospondin‐1 (TSP‐1)/VEGF, MCP‐1 and s‐ICAM. Future experiments will determine if prevention of venular leukocyte adhesion represents an effective target to blunt rarefaction (NIH RR2465AR; T32 HL90610, AHA 0740129N; AHA PRE3040016)
The effects of melatonin and/or forced exercise on reorganization of corticospinal tract after focal cerebral ischemia in rats
Authors: Lee Seunghoon , Lee Minkyung , Hong Yonggeun
Published: June 2021

Several mechanisms have been suggested for the rehabilitational approaches after stroke. These include the ipsilateral motor pathway from the unaffected brain to the affected extremities, peri‐lesional reorganization, and recovery of a damaged corticospinal tract (CST). The present study was performed to investigate the effect of melatonin (MT) and/or forced exercise (Ex) on reorganization of CST after focal cerebral ischemia (MCAo) in rats. Following the MCAo surgery, the 8‐week‐old Sprague‐Dawley rats were treated twice daily with MT (10 mg/kg) at 7:00 and 19:00 hr, and were treated with vehicle instead of MT. Also, there were trained twice daily with treadmill exercise (20m/min) at 17:00 and 22:00 hr. At day 7 after MCAo, the brain and spinal cord were collected and performed the histological analysis. It showed that the infarct area was significantly reduced in MT and MT+Ex groups compared to vehicle (p < 0.05, p < 0.01, respectively). Likewise, there were showed the myelination and sprouting of axon in left lateral CST. However, dorsal funiculus was showed a reduction of neural cell on left side in spinal cord. Preliminarily, these results suggest that improvement of functional and structural recovery by the re‐organization of lateral CST following the treatment of MT and MT+Ex, which further suggests the critical rehabilitative therapeutic approaches for recovery from neurological dysfunction due to stroke.
Modifying a high saturated fat diet with omega‐3 (n‐3) poly‐unsaturated fat improves vascular dysfunction and glucose intolerance
Authors: Lamping Kathryn G , Nuno Daniel W , Coppey Lawrence J , Hu Shanming , Oltman Christine L , Norris Andrew W , Sivitz William I , Yorek Mark A
Published: June 2021

We tested the hypothesis that partial replacement of dietary saturated fats with mono‐ or poly‐unsaturated fats improves glucose tolerance and vascular function. We fed C57BL6 male mice a high saturated fat diet (60% lard) for 12 wks before substituting half of the fat with poly‐ [n‐3 menhaden oil: MO or n‐6 safflower oil: SO] or mono‐unsaturated fat [olive oil: OO] for 4 wks. After 12 and 16 wks, weight and fasting glucose were elevated and glucose tolerance and insulin‐stimulated AKT phosphorylation in skeletal muscle were reduced in lard vs normal diet (4% fat) mice. Substitution with MO restored all but weight to normal whereas restoration was limited for SO and OO substitutions. To determine whether these fat‐modulated metabolic parameters correlated with vascular dysfunction, we evaluated reactivity of isolated pressurized gracilis arteries from each group. Although there was a modest reduction in relaxation to acetylcholine in mice fed lard, SO and OO compared to normal diet, there was no difference in relaxation but a marked reduction in contraction to phenylephrine of arteries from MO mice. Relaxation to nitroprusside was not different among groups. We conclude that enrichment of high fat diet with n‐3 poly‐unsaturated menhaden oil but not mono‐ or n‐6 poly‐unsaturated fats rapidly improves glucose tolerance, insulin signaling and vascular reactivity in skeletal muscle. Support: Dept Veterans Affairs
Roles of a macrophage molecule M‐mod in type 2 diabetes
Authors: Kitamura Hiroshi , Ito Masatoshi , Kimura Shunsuke , Shimamoto Yoshinori , Miyamoto Tomomi , Watarai Hiroshi , Okabe Jun , Iwanaga Toshihiko , Ohara Osamu , Miyoshi Ichiro
Published: June 2021

So far, we have identified a macrophage molecule, M‐mod (macrophage‐modulator), whose expression level was affected during differentiation. To explore biological roles of M‐mod, we established M‐mod knockdown (KD) cells using short hairpin RNA. Since M‐mod KD cells did not affect expression of CD11b and CD11c, M‐mod is dispensable for M1 macrophage differentiation. On the other hand, M‐mod KD potentiated expression of type2 diabetes‐associated genes such as adipocyte protein 2 (aP2), plasminogen activator inhibitor (PAI)‐1, and monocyte chemoattractant protein (MCP)‐1. In agreement, supernatant from M‐mod KD cells decreased insulin sensitivity of 3T3‐L1 adipocytes. M‐mod KD did not influenced phosphorylation of protein kinases (such as JNK, ERK, p38 and Akt) and their downstream transcriptional regulators (such as AP‐1, PPARs and NF‐κB). By contrast, M‐mod KD promoted methylation of histone H3 Lys4 at aP2 locus. Collectively, M‐mod might be an epigenetic suppressor of type2 diabetes‐associated genes in M1 macrophages. This study was supported by AstraZeneca, Ono Medical Research Foundation, and Suzuken Memorial Foundation.
Expression of gastrin in the thin descending limb of Henle's loop in the mouse kidney: a molecular, localization, and functional study
Authors: Yang Yu , Evans Sarah , Escano Crisanto , Asico Laureano , Zhang Yanrong , Gonzalez Santiago Cuevas , Villar Van Anthony , Wang Xiaoyan , Pisegna Joseph R. , Wank Stephen A. , Armando Ines , Jose Pedro
Published: June 2021

Gastrin is secreted mainly by G‐cells in the stomach and released into the circulation. It is taken up by renal tubules where it acts on cholecystokinin B receptors (CCKBR) to decrease sodium reabsorption. However, it is unknown whether or not gastrin can also be produced by the kidney and participate in the control of sodium homeostasis and blood pressure.

We used real‐time RT‐PCR to determine the expression of gastrin mRNA in different areas of the mouse kidney and found the gastrin transcript in both medulla and papilla, indicating that gastrin may be synthesized in the kidney. Gastrin immunoreactivity was detected in the thin descending limb of Henle's loop (TDLHL), which was confirmed by colocalization with aquaporin 1, a marker of TDLHL. Expression of gastrin protein was also found in mouse kidney homogenates. In contrast, real‐time RT‐PCR, western blotting, and immunostaining revealed no expression of gastrin in the kidney of gastrin knock‐out (Gast −/−) mice. In addition, Gast−/− mice have higher blood pressure and lower sodium excretion than Gast+/+ mice.

These results show for the first time that gastrin is expressed in the TDLHL of the mouse kidney. Furthermore, renal gastrin might contribute to increase sodium excretion and maintain normal blood pressure.
Acid Sphingomyelinase Gene Knockout Ameliorates Hyperhomocysteinemic Glomerular Injury in Mice Lacking Cystathionine β‐synthase
Authors: Boini Krishna M , Xia Min , Li Cai-Xia , Xiong Jing , Li Pin-Lan
Published: June 2021

Acid sphingomyelinase (ASM) have been implicated in the development of hyperhomocysteinemia (hHcys)‐induced glomerular oxidative stress and injury. However, it remains unknown whether genetically engineering of ASM gene produces beneficial or detrimental action on hHcys‐induced glomerular injury. The present study generated and characterized cystathionine β‐synthase (Cbs) double knockout (DKO) by cross breeding Cbs+/− and Asm+/−. Given that the homozygotes of Cbs−/−/Asm−/− DKO mice could not survive for 3 weeks. Cbs+/−, Asm−/− and Cbs+/−/Asm−/− as well as their wild type littermates were used to study the action of Asm−/− under a background of Cbs+/− with hHcys. HPLC analysis revealed that plasma Hcy level was significantly elevated in Cbs+/−/Asm+/+, Cbs+/−/Asm+/−, and Cbs+/−/Asm−/− mice (11.6±0.9, 11.4±0.9 and 11.8±1.0 μm) compared to their wild type littermates (4.3±0.6 μm). Cbs+/−/Asm+/+ mice had significantly increased renal Asm activity, O2− production and ceramide production compared to Cbs+/+/Asm+/+, while Cbs+/−/Asm−/− mice showed a significantly reduced hHcys‐induced renal Asm activity, O2− production and ceramide production. Confocal microscopy demonstrated that colocalization of podocin with ceramide was much lower in Cbs+/−/Asm−/− mice compared to Cbs+/−/Asm+/+ mice, which was accompanied by a reduced glomerular damage index, albuminuria and proteinuria in Cbs+/−/Asm−/− mice. Immunofluorescent analyses of the podocin and desmin expression also illustrated strong podocyte damages in the glomeruli from Cbs+/−/Asm+/+ mice, but not in Cbs+/−/Asm−/− mice. In in vitro studies of podocytes, hHcys‐enhanced O2− production and decreased VEGF level in podocytes were substantially attenuated by prior treatment with Amitriptyline, an Asm inhibitor. In conclusion, Asm protect the podocytes and glomeruli from hHcys‐induced oxidative stress and injury (supported by NIH DK54927, HL75316).
Eph and ephrin Expression during C2C12 Myogenesis
Authors: Fu Xing , Du Min
Published: June 2021

Eph receptors, a family of receptor tyrosine kinases, are divided into two groups, EhpA and EphB. Ephrin ligands, based on their selectivity for receptors, are also divided into ehprinA and ehprinB. Eph/ephrin signaling is bidirectional and mediates both cell repulsion and attraction. During myogenesis, myoblasts need to align together during fusion into myotubes, which suggests that Eph/ephrin signaling may play important roles in the fusion of myoblasts into myotubes. To test this, C2C12 cells were induced fusion and the mRNA expression of Ephs (EphA1‐A8, EphA10, EphB1‐B4 and EphB6) and ephrins (ephrinA1‐A5 and ephrinB1‐B3) were analyzed. Data showed that all the Eph receptors except EphA3, EphA5, EphA6, EphA8, EphA10, and EphB3 and all the ephrin ligands were expressed in C2C12 cells during myogenesis. The expression level of EphA1, EphA7, EphB3, EphB6, ephrinA1, ephrinA4, and ephrinB2 in C2C12 dramatically increased as fusion was induced. Several Eph receptors and ephrin ligands were chosen for further research. Knock down experiment is now in progress to test their possible roles in the fusion of myoblasts into myotubes. This research is funded by NIH grant R01HD067449.
The role of macrophages in lung inflammation in a mouse model of chronic bronchitis
Authors: Saini Yogesh , Terrell Kristy , O'Neal Wanda K , Boucher Richard C
Published: June 2021

Chronic bronchitis is a characteristic manifestation of cystic fibrosis and chronic obstructive pulmonary disease. Scnn1b‐Tg mice overexpresses the Scnn1b in airway Clara cells, resulting in increased Na+ absorption, airway surface liquid depletion, mucus adhesion to airway surfaces and airway inflammation. Macrophages are thought to play a pivotal role in regulating the initiation, maintenance, and resolution of inflammation. However, the specific role of macrophages in the development of pulmonary disease in the Scnn1b‐Tg mice is still unknown. We adopted a genetic approach to deplete macrophages in the context of the Scnn1b‐Tg mice in order to evaluate the effect on disease development. The approach utilized macrophage‐specific LyzM promoter to induce the expression of Cre recombinase leading to diphtheria toxin‐induced macrophage depletion. Preliminary studies show that >70% macrophage depletion is achievable. More than 60 % macrophage‐deficient Scnn1b‐Tg mice show significant weight loss with a high degree of mortality in the first 2 weeks of life. Analyses of cells from BALF samples at birth and at the age of 5–7 days show profound neutrophilic infiltration with occasional giant cells. BALF Microbiological analyses show uncontrolled microaerophilic bacterial growth. Taken together, our current data suggest that the lung macrophages play a critical role in the resolution of airway inflammation.
Diesel Exhaust Particulate Matter has both Direct and Indirect Effects on Cardiomyocyte Function
Authors: Gorr Matthew William , Rodeman James Daniel , Cormet-Boyaka Estelle , Wold Loren Eugene
Published: June 2021

Exposure to particulate matter (PM) provokes a variety of pathological responses to multiple organ systems. PM particles with a size less than 2.5 μm (PM2.5) have the most physiological relevance, as they are capable of both manifestation into the lung epithelium, and entrance into the bloodstream. Therefore, PM2.5 has the capacity for both direct and lung‐mediated indirect effects on the heart. In the present study, we cultured isolated rat cardiomyocytes with PM2.5 at various concentrations for 3 hours. Additionally, various concentrations of PM2.5 were added to the apical compartment of polarized human bronchial epithelial cells, 16HBE14o‐ to mimic lung exposure. The basal media was collected 24 hours later and used to culture myocytes for 3 hours. Myocytes from both treatments were stimulated in contractile buffer at 1 Hz, and functional analyses were performed using the real‐time IonOptix system. Baseline % Peak Height was significantly reduced with direct PM2.5 culture (7.05±2.07% vs. 4.85±2.68% at 100 μg/ml) and in co‐culture from epithelial cells treated at various concentrations (7.37±3.00% vs. 4.58±2.05 at 100 μg/ml). These results indicate the presence of both direct and indirect effects of PM2.5 on cardiomyocyte function. Future work will elucidate the mechanisms involved in these pathways.
Differential anoxia and hypoxia tolerance in two color morphs of the green crab, Carcinus maenas
Authors: Toombs Casey Ann , Jost Jennifer A. , Frederich Markus
Published: June 2021

Despite the name green crab, Carcinus maenas displays red and green color morphs. Earlier studies using organismic parameters suggest differences in stress tolerance between the color morphs without a detailed study on their cellular physiology. We tested the hypothesis that the differential stress tolerance at the organismic level is reflected in a difference in cellular stress parameters during anoxia and hypoxia. Crabs of both color morphs were exposed to 2 h anoxia or up to 24 h hypoxia. For organismic parameters, we analyzed righting response, heart rate, oxygen consumption, and running endurance on a treadmill. At the cellular level, we measured heart tissue lactate accumulation, AMP‐activated protein kinase (AMPK) activity and mRNA expression, and heat shock protein (HSP70) levels and mRNA expression. At the organismic level, color morphs showed no differences during normoxia and anoxia. Only during hypoxia did green morphs perform better. At the cellular level green morphs showed elevated levels of stress parameters such as AMPK and HSP70, which contradicts earlier publications that describe green morphs as more stress tolerant. Our findings provide the first data of cellular differences between color morphs and question the assumption that green color morphs are generally more stress tolerant than red morphs. Funded by NSF‐IOB 0640478 to MF and an APS summer fellowship to CAT.
Cytochrome P‐450 2J epoxygenase gene function in murine hypoxic pulmonary vasoconstriction (HPV)
Authors: Beloiartsev Arkadi , Zhou Guo Ling , Bloch Kenneth D. , Seed Brian , Zapol Warren M.
Published: June 2021

Recent studies suggest that cytochrome P‐450 (CYP) epoxygenase‐derived epoxyeicosatrienoic acids (EETs) play an important role in the regulation of the pulmonary vascular tone. To assess the role of the CYP2J‐signaling pathway in HPV, we studied CYP2J+/+ and CYP2J−/− mice, as well as CYP2J−/− mice carrying a transgene specifying human CYP2J (CYP2J−/−‐Tg). Mice were anesthetized, intubated, and ventilated at FIO2=1. After thoracotomy, pulmonary artery pressure (PAP) and left lung blood flow (QLPA) were measured before and during transient inferior vena cava occlusion. Left pulmonary vascular resistance (LPVR) was calculated from the slope of the PAP‐QLPA relationship. The pulmonary vasoconstrictor response to unilateral left lung hypoxia was estimated by comparing LPVR before and after left main stem bronchial occlusion (LMBO). LMBO increased LPVR in CYP2J+/+ and CYP2J−/−‐Tg mice but not in CYP2J−/− mice (see Table). PaO2 during LMBO was greater in CYP2J+/+ and CYP2J−/−‐Tg mice than in CYP2J−/− mice. Administration of MS‐PPOH, a selective inhibitor of CYP‐mediated epoxygenation, blocked the ability of LMBO to increase LPVR in CYP2J+/+ mice. Taken together, these results indicate that CYP2J epoxygenase contributes importantly to HPV in mice. (Supported by MGH, Department of Anesthesia, Critical Care and Pain Medicine).
Physical (in)activity leads to neuroplastic changes in the rostral ventrolateral medulla (RVLM)
Authors: Speirs Susan L , Mischel Nicholas A , Mueller Patrick J
Published: June 2021

Individuals who lead a sedentary lifestyle are at increased risk of cardiovascular disease. C1 neurons in the rostral ventrolateral medulla (RVLM) express tyrosine hydroxylase (TH) and are important in blood pressure regulation. We have hypothesized that the RVLM undergoes neuroplastic changes that increase sympathoexcitation in sedentary (SED) versus physically active animals. To test this hypothesis, TH immunohistochemistry was performed on 150 μm thick sections from SED rats or rats housed with running wheels (WRs, 14 wks). The caudal pole of the facial nucleus (CP7) was used as a reference point for blinded cell counts. TH+ cells were distributed rostral‐caudally in both groups, however, SED rats had significantly greater TH+ cells near CP7 (92±14 vs. 31±8 cells, p<0.05). TH+ cells were not different 600 μm caudal to CP7 (64±12 vs 60±5 cells). These data suggest that TH+ neurons projecting to the spinal cord but not hypothalamus undergo neuroplasticity due to physical activity, inactivity or both. Knowledge from these studies may lead to treatment options in patients who are unable or unwilling to exercise. (APS Frontiers Program; F30HL105003; R01HL096787).
Impact of sleep disordered breathing and arousal state on the hypoxic ventilatory response and ventilatory long‐term facilitation
Authors: Syed Ziauddin , Lin Ho-Sheng , Mateika Jason H.
Published: June 2021

Purpose

To examine the impact of sleep disordered breathing and arousal state on the magnitude of the hypoxic ventilatory response (HVR) and ventilatory long‐term facilitation (vLTF) during and after exposure to intermittent hypoxia (IH), respectively.

Methods

Ten healthy males and 8 males with obstructive sleep apnea (OSA) were exposed to IH on two occasions; once during wakefulness and the other during sleep. The IH protocol consisted of 12‐2 min episodes of hypoxia (PETO2 – 50 mmHg) in the presence of PETCO2 levels sustained 3 mmHg above baseline. Each episode was followed by a 2 min normoxic recovery period with the exception of the last recovery period which was 30 min in duration.

Control
OSA

Wake
Sleep
Wake
Sleep

HVR
0.61±0.07*
0.46±0.06
0.64±0.10*
0.51±0.14

VE
1.19±0.03*§
1.09±0.03§
1.37±0.11*§†
1.13±0.05§†

VT
1.13±0.02*§
1.08±0.03§
1.27±0.07*§
1.09±0.05§

Bf
1.06±0.03§
1.00±0.01
1.08±0.04§
1.03±0.03

VE, VT, Bf ‐standardized to baseline. Significantly different from sleep (*) and baseline (§) p < 0.05. Trend toward a difference from control (†) p < 0.07.

Results & Conclusions

vLTF was evident during wake and sleep; however, the magnitude of vLTF as well as HVR was greater during wakefulness. The magnitude of vLTF tended to be greater in the OSA group compared to control. VT was the primary component responsible for vLTF during sleep while Bf also contributed to vLTF during wakefulness.

Funding: VA Merit & NIH
GAL‐021, a novel respiratory stimulant, attenuates opioid–induced respiratory depression without compromising analgesia
Authors: Baby Santhosh M , Gruber Ryan B , Puskovic Veljko , Peng Sean , Dax Scott L , Golder Francis J , MacIntyre D Euan , Mannion James C
Published: June 2021

Opioid‐induced respiratory depression (OIRD) is a common side effect of opioid analgesics and can be life‐threatening, especially during the perioperative period and sleep. Current therapy for OIRD includes administering opioid antagonists and/or decreasing subsequent opioid doses, both of which can compromise analgesia. Here, we describe a novel respiratory stimulant, GAL‐021, that increases minute ventilation (Vmin) and reverses OIRD without diminishing analgesia. GAL‐021 administered as an IV bolus (0.01 – 3 mg/kg) to anesthetized rats or by infusion (0.01 – 0.4 mg/kg/min × 60‐min) to conscious rats increased Vmin, tidal volume (VT), and respiratory frequency (f). In anesthetized rats, the ED50 for increasing Vmin was 140 μg/kg. In conscious rats, OIRD was induced with morphine (10 mg/kg, IV), which increased PaCO2 and decreased Vmin, VT, f, pH, and PaO2 for up to 2 hours. Subsequent infusion of GAL‐021 (0.03 – 0.4 mg/kg/min, IV) resulted in dose‐dependent diminution of the evoked respiratory depression for the duration of the infusion (20 min). The increase in Vmin induced by GAL‐021 was due to an increase in VT but not f. Termination of GAL‐021 infusion restored OIRD. In contrast, GAL‐021 did not diminish morphine‐induced analgesia assessed by the tail‐flick assay. These data demonstrate that GAL‐021 stimulates breathing in conscious and anesthetized rats and reverses OIRD without attenuating analgesia.