bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of short‐ and long‐duration exercise at the ventilation threshold on subjective appetite and short‐term food intake in children
Authors: Bellissimo Nick , Bozinovski Natalie C. , Thomas Scott G. , Pencharz Paul B. , Anderson G. Harvey
Published: June 2021

The effect of exercise on subjective appetite and short‐term food intake has received little study in children. The purpose of this study was to determine the effect of exercise at the ventilation threshold (VeT) on subjective appetite and short‐term food intake in normal weight children (9‐14 years). On 4 separate mornings and in random order, boys and girls (n = 24) completed 4 study sessions of rest or exercise for 15 (short‐duration; SD) or 45 min (long‐duration; LD) 2 h after a standardized breakfast of milk, cereal, and orange juice. Food intake (FI) from a pizza meal was measured 30 min after rest or exercise. Subjective appetite was measured at regular intervals during the study sessions. VeT was determined on a separate day. FI (mean kcal ± SEM) after SD (1087 ± 80) and LD (1131 ± 85) exercise was similar to rest (SD: 1127 ± 99; LD: 1112 ± 94) (p = 0.6). The energy cost of exercise for SD and LD exercise was 75± 4 kcal and 227 ± 13 kcal, respectively. Both exercise sessions resulted in a net energy deficit (SD: ? = ‐115 ± 42, p < 0.01; LD: ? = ‐208 ± 31, p < 0.0001) compared with rest. Furthermore, subjective average appetite increased over time (p<0.0001), but was similar between rest and exercise. In conclusion, short‐term FI is not increased by SD or LD exercise at the VeT and may be an effective strategy to promote healthier body weights in children. Supported by CIHR.
CO2 status as a controller of blood flow redistribution and auto‐resuscitation during anoxia‐induced apnea in the sheep
Authors: Ferguson Carrie , Bell Harold James , Haouzi Philippe
Published: June 2021

Spontaneous recovery of eupnea following an anoxia‐induced apnea (i.e. auto‐resuscitation ‐ AR) is reliant upon the transition to a "gasping" breathing pattern. Blood flow redistribution is likely to be an important determinant of successful AR by optimizing the reoxygenation process. We investigated how the duration of anoxia‐induced apnea and transition to and from gasping are influenced by factors affecting blood flow redistribution; specifically, we altered CO2 stores and the capacity for hypoxia‐induced sympathetic vasoconstriction. In 5 urethane‐chloralose anesthetized spontaneously breathing sheep, apneas were induced by breathing nitrogen, with and without 5% CO2 before, and then following administration of phentolamine. Following hypocapnic anoxic apnea, AR occurred after 95±21s, typically after 2 gasps. The duration of apnea was reduced in the presence of hypercapnia (77±26s). Phentolamine delayed hypocapnic AR (149±75s), led to more gasping, and profoundly altered AR with hypercapnia. Indeed hypercapnic AR failed in 2 sheep, while in the remaining 3 sheep apnea was significantly prolonged (115±36s). Our results suggest hypercapnia facilitates effective blood flow redistribution and reduces the duration of apnea when vasomotor control is intact. However, when anoxia‐induced vasoconstriction is blocked, the presence of hypercapnia compromises and can even prevent successful AR.
Effects of sex hormones on metabolic rate, ventilation and respiratory‐related upper airway muscle activities in female rats
Authors: Richardson Patrick A. , Fregosi Ralph F. , Hoyer Patricia B , Bailey E. Fiona
Published: June 2021

We tested the hypothesis that changes in sex hormones in female rats resulting from ovarian failure induced by exposure to 4‐vinylcyclohexene diepoxide (VCD) alter metabolism, ventilation and respiratory‐related upper airway muscle activities.

Two groups of Fischer‐344 female rats were used, one group injected daily with VCD, 80 mg/kg i.p. for 25 days (N=5), the other an age‐matched control group (N=5) injected daily with sesame oil. We obtained in‐vivo measures of VCO2/VO2, tidal volume (VT ) and breathing frequency (FR) using a sealed whole‐body plethysmography chamber. In the same animals, we recorded EMG activities of hyoglossus (HG) and genioglossus (GG) muscles and esophageal pressure (Pes) under urethane anesthesia in hyperoxia (FICO2=0) and hyperoxic hypercapnia (FICO2=0.03, 0.06, 0.09, 0.12 balance O2).

Preliminary data reveal increased basal VO2, VCO2 and the ratio of VCO2/VO2 for VCD treated rats relative to age‐matched controls. Measures of ventilation and whole muscle EMG were comparable for the two groups in hyperoxia whereas VCD treated rats exhibited a trend toward higher VT and FR and greater average GG and HG EMG activities in hyperoxic hypercapnia relative to the age‐matched controls.

These studies provide preliminary insights into metabolic rate, ventilation and respiratory‐related upper airway activities as a function of ovarian failure in age‐matched controls.
Renal damage in the non‐clipped kidney in two kidney one clip rat is most pronounced in the juxtamedullary cortex.
Authors: Skogstrand Trude , Hultström Michael , Iversen Bjarne Magnus
Published: June 2021

Renal damage in old spontaneous hypertensive rats (SHR) was found to start in the juxtamedullary cortex (JMC) and extend towards the outer cortex (OC), with a clear difference in gene expression for the enzymes involved in collagen metabolism in the two compartments. In the present study we studied the progression of hypertensive renal damage in the non‐clipped kidney of two kidney, one clip (2k1c) rats, 6, 16 and 24 weeks after clipping. The mean arterial pressure was increased after 2‐4 weeks, and was 166±9 mmHg in the 2k1c group and 116±7 mmHg in the control group after 24 weeks. The 6 and 16 week group showed no histological damage, or up regulation of the mRNA expression of collagen type‐1‐A1 (col1a1), procollagen‐n‐ and c‐peptidase (n‐pep, c‐pep). At sacrifice the 24 week 2k1c group had a protenuria of 760±251 mg/mmol creatinine, higher than in the control group (92± 12 mg/mmol creatinine, p<0.05). The mRNA expression of col1a1 and n‐pep in the JMC in 2k1c was higher than in the OC, and higher than in the control group. We found no difference in the expression of c‐pep.

In conclusion, it looks like our previous findings of a progression of renal damage from JMC towards OC in SHR, is a systematic feature of hypertensive renal damage. The increased expression of n‐pep may be an important mechanism in the increased collagen deposition.

The study was funded by the University of Bergen and Helsevest, Norway
Interaction of protease‐activated receptor 2 with chronic angiotensin II‐induced endothelial dysfunction in mice
Authors: McGuire John , Hughes Keon , Halfyard Sarah , Wijekoon Enoka
Published: June 2021

Protease‐Activated Receptor 2 (PAR‐2) knockout mice exhibit a different time course in blood pressure response to angiotensin II (AngII). In this study we measured endothelium‐dependent relaxations of mesenteric arteries from PAR‐2 knockout (PAR‐2 ‐/‐) and C57BL/6 mice using wire myographs. Our goal was to test the influence of PAR‐2 ‐/‐ on AngII‐induced endothelial dysfunction. Chronic AngII infusion of C57BL/6 and PAR‐2 ‐/‐ decreased acetylcholine (ACh)‐induced relaxations by ~20 % whereas PAR‐2 agonist (2fly) and sodium nitroprusside relaxations were unchanged relative to saline infusion groups. ACh‐induced relaxations of AngII‐PAR‐2 ‐/‐ arteries, but not AngII‐C57BL/6 arteries, were rescued in the presence of the cyclooxygenases inhibitor indomethacin. In contrast to these effects, indomethacin decreased the sensitivity to ACh in saline‐PAR‐2 ‐/‐ and did not affect either ACh‐ or 2fly‐induced relaxations in saline‐C57BL/6. The sensitivity to 2fly of arteries from AngII‐C57BL/6 was decreased in the presence of indomethacin. A combination of PAR‐2 gene knockout and indomethacin rescued ACh‐induced relaxations of vascular smooth muscle after chronic AngII infusion in mice. Cyclooxygenases contribute to the mechanism of persistent PAR‐2 vasodilation despite endothelial dysfunction and to the mechanism of action for ACh in PAR‐2 ‐/‐ mice. Funding sources: CIHR, IRIF, CFI.
CARDIOVASCULAR EFFECTS OF ACETYLCHOLINE MICROINJECTED INTO THE LATERAL PERIAQUEDUCTAL GRAY AREA OF RATS.
Authors: Deolindo Milena vieira , Pelosi Gislaine , Correa Fernando Morgan de Aguiar
Published: June 2021

INTRODUCTION

The periaqueductal gray area (PAG) is a mesencephalic region that is involved in the modulation of cardiovascular changes associated with behavioural responses. Among the neurotransmitters present in the PAG, acetylcholine (Ach) is also known to be involved in central cardiovascular control. In the present study, we attempted the cardiovascular effects of the microinjection of Ach into the lateral portion of the PAG (lPAG) of rats.

METHODS

Male Wistar rats were used. Guide cannulas were implanted in the lPAG for drug injection and a polyethylene catheter was implanted in the femoral artery for arterial pressure (AP) and heart rate (HR) recording using a computerized acquisition system.

RESULTS

The injection of different doses of Ach (27 and 81nmol/ 50nl) into the lPAG of unanaesthetized rats caused dose‐related depressor responses accompanied by bradycardia. However, the injection of different doses of Ach (27 and 81nmol/50nl) into the lPAG of anaesthetized rats caused dose‐related depressor responses accompanied by tachycardia.

CONCLUSION

The present results indicate that activation of cholinergic receptors within the lPAG can evoke cardiovascular responses of rats.

FINANCIAL SUPPORT

Fapesp (07/50166‐1) and Fapesp (05/57227‐0)
Statins may protect against HIV‐1 induced amyloid beta accumulation in the blood‐brain barrier
Authors: Andras Ibolya E , Hennig Bernhard , Toborek Michal
Published: June 2021

An increase in the older population infected with HIV‐1 is an emerging development in HIV‐1 epidemiology. We hypothesize that amyloid beta and HIV‐1 can potentiate their toxic effects at the blood‐brain barrier (BBB) level. We employed an in vitro model of human brain microvascular endothelial cells (HBMEC) directly exposed to HIV‐1 or co‐cultured with HIV‐1 infected human monocytes. Exposure of HBMEC to fluorescently labeled amyloid beta (1‐40) in the presence of HIV‐1 resulted in increased amyloid beta binding/entry into HBMEC. The presence of HIV‐1 alone was sufficient to enhance the intensity of amyloid beta immunoreactivity in HBMEC. These observations suggest that HIV‐1 can both increase binding/entry of externally added amyloid beta and elevate endogenous amyloid beta. Simvastatin, the HMG‐CoA reductase inhibitor, blocked only the HIV‐1 induced binding/entry of exogenous amyloid beta in HBMEC. In addition, RAGE immunoreactivity (RAGE: receptor for advanced glycation end products, involved in the transport of amyloid beta across the BBB into the brain) was stronger and RAGE protein levels were elevated in HBMEC exposed to HIV‐1 as compared to control and simvastatin attenuated these effects. Our results suggest that statins, such as simvastatin, may protect the BBB against amyloid beta accumulation induced by HIV‐1 infection. Supported by MH63022, MH072567, and NS39254.
Microparticle (MP) formation and matrix metalloproteinase (MMP) activation during ventilator induced lung injury (VILI)
Authors: Hamanaka Kazutoshi , McLean Matt , Frost J. Richard , Weber David S. , Parker James C.
Published: June 2021

Ventilation with high peak inflation pressures (PIP) induces increased lung vascular permeability. Activation of MMP causes proteolytic breakdown of cell adhesion proteins and contributes to the increased permeability in VILI. MPs are membrane enclosed particles less than 1 micron diameter, produced by cell activation, exocytosis or apoptosis, and are known to produce endothelial cell dysfunction. To determine a possible link between MP and MMP activation, we ventilated C57/BL6 mice at 50 cmH2O PIP for 2 hours. Plasma MP numbers increased eightfold compared to unventilated controls while MP counts in BAL were similar. Using flow cytometry for surface proteins, 30% of plasma MP expressed CD31, CD54 and CD61, whereas approximately 50% expressed CD106, CD147, and E‐cadherin. In lungs ventilated with high PIP compared to low PIP (9 cmH2O), MMP‐2 activity increased 2‐fold in lung tissue and 25‐fold in BAL; MMP‐9 activity increased 2‐fold in lung tissue and 4‐fold in plasma, and tissue inhibitor of metalloproteinase (TIMP) decreased by 30% in lung tissue. Collagenase activity was approximately 2‐fold higher in MP compared to supernatant in both plasma and BAL. These data indicate that MP increased during VILI and possess surface proteins and MMP activity to bind to and degrade junctional proteins. MP may serve as targeted agents which contribute to increased vascular permeability during VILI. Supported by P01 HL66299.
Airway acid instillation promotes procoagulant lung endothelial mechanisms in mouse
Authors: Huertas Alice , Yiming Maimaiti , Bhattacharya Sunita
Published: June 2021

We showed airway acid instillation caused lung endothelial (EC) protein tyrosine phosphorylation (Yiming, Faseb. J. 20: 2006). Here we addressed the underlying role of oxidative stress. We instilled normal saline (NS) or hydrochloric acid (HCI, pH1.2, 2ml/kg) in anesthetized mouse airway. 2 h later, injecting heparin, we cleared the pulmonary vasculature with ice‐cold buffer, then perfused chilled collagenase (1000 units/ml) and trypsin (3ml) (Yiming, AJRCMB 2008), to obtain an effluent containing ~4x104 EC. Using fluorophore‐conjugated mAbs, we surface labeled EC for the EC marker vWf or in fixed and permeabilized EC (paraformaldehyde, 2%, triton 0.1%) labeled vWf and phosphorylated tyrosine. We determined fluorescence by flow cytometry. As compared with saline, acid instillation markedly increased EC surface vWf and EC tyrosine phosphorylation (p<0.05, n=3). However, in the oxidant‐incompetent gp91phox‐/‐ mouse, acid‐mediated vWf expression and tyrosine phosphorylation were markedly blunted (p<0.05, n=3). Taken together, our findings in wild type and gp91phox‐/‐ mouse indicate oxidant stress promotes airway acid instillation‐induced EC tyrosine kinase activation and platelet adherence molecule expression. We suggest that acute lung injury in acid aspiration results from an oxidant‐induced platelet‐adhesive endothelial surface (Support: HL36024).
Increased ADMA/protein methylation modulates nitric oxide generation in hypoxic human lung microvascular endothelial cells
Authors: Han Zhaosheng , Pope Arthur J. , Cardounel Arturo J. , Nelin Leif D , Chicione Louis G.
Published: June 2021

Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of nitric oxide (NO) synthase (NOS) and is elevated in serum of animals exposed to chronic hypoxia. We tested the hypothesis that exposing endothelial cells (EC) to hypoxia would increase ADMA levels and thereby decrease NO production. Human lung microvascular EC were exposed to normoxia or hypoxia (1% O2) for 48 hours, NO generation and ADMA were measured using EPR and HPLC, respectively. eNOS, protein arginine methyltransferases2 (PRMT2), dimethylarginine dimethylaminohydrolases I and II (DDAH) were assayed by Western blot. Assessment of protein methylation was performed by immunoprecipatation/immunoblotting. We found that NO production was reduced by 30% following 48h of hypoxia compared to normoxia. The protein levels of eNOS were similar between normoxic and hypoxic EC. Furthermore, we found that ADMA, methylated protein, and PRMT2 were increased by 112%, 105%, and 113%, respectively in hypoxic compared to normoxic EC. DDAH1 protein levels were decreased by 50% in hypoxia, while DDAH2 protein was undetectable. Thus, hypoxia caused an increase in PRMT2 and reduced DDAH1 leading to an increase in ADMA levels and an associated decrease in NO production. Therefore, we conclude that the increased ADMA/protein methylation due to enhanced PRMT2 and diminished DDAH protein may play an important role in hypoxia induced reduction of NO production.
Multivalent Tethered Ligands Enhance Cell Targeting Specificity and Reactivity
Authors: Weber Craig , Vagner Josef , Xu Liping , Gillies Robert , Lynch Ronald
Published: June 2021

Specific cells types can be identified by markers expressed on their surfaces (e.g., receptors). Ligands for single receptors usually do not provide enough specificity for targeting only the cell type of interest, particularly for cells found in low number. However, targeting a combination of surface markers may greatly enhance specificity. To test this, we developed a multivalent ligand (MVL) of melanocyte stimulating hormone (MSH) and cholecystokinin (CCK) linked together, then evaluated the binding affinity, specificity and activity of this agent. Relative to monvalent MSH or CCK the apparent binding affinity of the multivalent MSH‐CCK was enhanced ~80 fold. To obtain this enhanced binding, the linker length needed to be greater than ~80 atoms of polyethyleneglycol. This MVL clearly distinguished cells expressing both receptors from those expressing only CCK or MC receptors, at low concentrations (<0.4 nM) demonstrating elevated specificity. Within 10 minutes of incubation, the MVL was capped and endocytosed from the cell surface. Moreover, the MVL of MSH‐CCK exhibited CCK like activity (elevation of cell Ca2+), but at concentrations 10X less than required for CCK activation. This work lays the foundation for further development and detailed study of a range of multimeric ligands to enhance cell specific targeting, and activation.
Comparative genomic analyses of trace element utilization and evolution
Authors: Zhang Yan , Gladyshev Vadim N
Published: June 2021

Trace elements are needed in minute quantities for proper growth, development, and physiology of organisms. Although many trace element‐containing proteins are well characterized, little is known about the global trends in trace element utilization. We carried out comparative genomic analyses to examine occurrence and evolution of the utilization of five trace elements, including copper (Cu), molybdenum (Mo), nickel (Ni), cobalt (Co) and selenium (Se), in more than 700 sequenced prokaryotes and eukaryotes at the level of (i) transport and/or utilization traits, and (ii) trace element‐dependent proteins. Only few organisms were found to utilize all five elements whereas most intracellular symbionts and parasites lacked the ability to use any of them. Cu and Mo were the most frequently used elements in bacteria and archaea, respectively. The presence of metal transporters generally matched the occurrence of corresponding utilization traits. Se utilization was detected in less about 25% prokaryotes, revealing a scattered and reduced usage of this metalloid. In eukaryotes, the utilization of Cu, Mo and Se was found in at least half of sequenced species, whereas that of Ni and Co was limited. Investigation of the metalloproteomes and selenoproteomes suggested increased utilization of trace elements in some organisms. Finally, environmental factors appeared to affect the utilization of trace elements.
Role of ghrelin in cell recovery following myelosuppressive chemotherapy
Authors: Fahim Mohamed Abdelmonem , Kataya Hazem , Karam Sherif , al‐Ramadi Basel
Published: June 2021

Ghrelin is a peptide hormone produced by cells of the stomach in response to negative energy balance. Ghrelin promotes growth hormone secretion from the pituitary via binding to a G‐protein‐coupled growth hormone secretagogue receptor. Acumulating evidence has hinted that ghrelin may have diverse biological functions in different systems, including the immune system. Ghrelin receptors are known to be expressed on T cells and macrophages, and these cells have been shown to secrete ghrelin. In the current study, we assessed the influence of ghrelin on recovery of bone marrow‐derived cells following chemotherapy. C57BL/6 mice were given a high dose of either Doxorubicin (10 mg/kg, i.v.) or 5‐Fluorouracil (100 mg/kg, i.v.) with or without daily i.p. injections of ghrelin. WBC, RBC and platelets were substantially reduced by 4 days after administration of chemotherapy and began to recover by day 9. Ghrelin was administered i.p. in 3 different regimens: 4ng/kg body weight every 48 hours, 10 μg/kg body weight every 48 hours, and 20 μg/day given in twice daily injections for 5 consecutive days. The recovery of WBC, RBC and platelet counts was followed for up to 14 days post chemotherapy administration. The results showed that at the doses of ghrelin used, there was no difference in the rate of recovery of the three cell populations in mice co‐injected with 5‐FU and ghrelin.

Supported by a grant from UAE University Research Affairs.
Inhaled nitric oxide improves left ventricular function during myocardial ischemia
Authors: Neye Nils , Habazettl Helmut , Plesnila Nick , Kuebler Wolfgang M.
Published: June 2021

Inhaled nitric oxide (NOi) exerts extra‐pulmonary effects by formation of nitrite and/or S‐nitrosohemoglobin. Both release NO during hemoglobin desaturation, and may thus redistribute blood flow selectively to areas in need (Robin Hood Effect). Here, we studied the effects of NOi on left ventricular function and infarct size in a rat model of myocardial infarction (MI).

MI was induced by occlusion of the left anterior descending (LAD) artery for 2 h. Rats were either sacrificed or reperfusion was re‐instated for 3 h. 50 ppm NOi was given during ischemia . Arterial pressure (AP), left ventricular pressure (LVP) and contractility (dp/dt) were measured, and infarct size and area at risk (AAR) were determined by methylene‐blue and tetrazolium red staining.

After 2 h LAD occlusion, NOi had increased mean AP from 55.1±2.3 (in untreated controls) to 67.6±2.1 mmHg, systolic LVP from 66.3±2.8 to 80.2±2.6 mmHg, and dp/dt (max) from 1536±54 to 2287±62 mmHg/s (n=10 each, *p<0.05). NOi also reduced AAR from 39.7±1.8 to 28.7±0.9% of the left ventricle. After additional 3 h of reperfusion without NOi, mean AP, systolic LVP and dp/dt (max) were still higher in rats which had received NOi during ischemia as compared to controls, while infarct size was reduced from 24.7±2.5% to 17.4±0.3%.

NOi improves left ventricular function during myocardial ischemia, presumably by selectively improving collateral blood flow to the AAR.
A role of PFKFB3/iPFK2 in the regulation of high fat diet‐induced inflammation and metabolic responses
Authors: Guo Xin , Li Honggui , Wu Chaodong
Published: June 2021

Feeding of a high fat diet (HFD) is shown to induce inflammation and dysregulated metabolic homeostasis. Here we show that PFKFB3, a gene whose product controls glycolysis, plays a pivotal role in the regulation of HFD‐induced inflammatory and metabolic responses. Upon feeding a HFD, C57BL6 wild‐type mice exhibit a significant increase in body weight, which is associated with increased fat accumulation in both the liver and adipose tissue. This weight gain‐effect of HFD feeding is significantly lessened in mice that lack one allele of PFKFB3 (PFKFB3+/− mice). In addition, there are no increases in fat accumulation in both the liver and adipose tissue of HFD‐fed PFKFB3+/− mice. However, compared to HFD‐fed wild‐type mice, HFD‐fed PFKFB3+/− mice exhibited a greater increase in tumor necrosis factor α(TNFα) and interleukin 6 (IL6) expression in both the liver and adipose tissue, indicating elevated inflammation. Moreover, plasma levels of glucose in HFD‐fed PFKFB3+/− mice are much higher than those in HFD‐fed wild‐type control mice, which are accompanied by exacerbated glucose intolerance and insulin resistance. Together, these findings demonstrate that PFKFB3 is crucial for the regulation of HFD‐induced inflammation and dysregulated metabolic homeostasis. Approaches that stimulate PFKFB3 expression may be viable to prevent or treat diabetes.

Grant Funding Source

none
Calcium absorption and vitamin D status in school age children
Authors: Abrams Steven A , Hicks Penni D , Hawthorne Keli M
Published: June 2021

Increasing serum 25‐hydroxyvitamin D (25‐D) in adults may enhance calcium absorption (Ca‐Abs). There are few similar pediatric data. We evaluated the relationship between 25‐D and Ca‐Abs by pooling data from 439 Ca‐Abs measurements over a 15 yr period at our center in 251 healthy children 4.9 to 16.7 yrs of age. Serum 25‐D ranged from 28 to 197 nmol/L (Mean 85 nmol/L). Ca‐Abs was correlated to 25‐D in the whole population, r = 0.16, p = 0.001. This relationship was closer in the 197 studies in early puberty (Tanner 2 or 3), r = 0.35, p < 0.001. We found no close relationship between Ca‐Abs and 25‐D in the 206 studies in which 25‐D was <80 nmol/L (r= 0.08, p = 0.24), including the 113 studies conducted in early puberty (r = 0.002, p = 0.98). In early puberty, Ca‐Abs was 111 ± 21 mg/d (SEM) greater in studies in which 25‐D was >80 nmol/L compared to those in which it was <80 nmol/L. This difference was not seen in prepubertal (Tanner 1) or postpubertal (Tanner 4 or 5) subjects. Improving vitamin D status may have limited effects on Ca‐Abs in healthy children except when 25‐D >80 nmol/L is achieved during early puberty.
Role of Hippo Kinase Pathway In Pathogenesis of Hepatocellular Carcinoma.
Authors: Wolfe Andy , Apte Udayan
Published: June 2021

The Hippo Kinase pathway regulates organ size in mammals and is also implicated in pathogenesis of various cancers. We have investigated the role of Hippo Kinase pathway in pathogenesis of hepatocellular carcinoma (HCC). Three HCC cell lines investigated, Hep3B, HepG2 and Huh7, demonstrated increase in Yes‐associated protein (YAP), the downstream effector of the Hippo Kinase pathway as compared to normal human hepatocytes. Increase in Ser127‐phorphorylated of YAP, which is shown to be an anti‐apoptotic and pro‐survival signal in cancer cells, was observed in all HCC cell lines. Large tumor suppressor‐1 (Lats1), an upstream kinase known to phosphorylate YAP was induced in HCC cell lines along with MOB1, a protein known to cooperate with Lats1 in phosphorylation of YAP. Mst2, a member of STE20‐kinase family, which activates Lats1, was also increased in the HCC cells. Immunofluorescence analysis indicated YAP localization both in nucleus and cytoplasm while Lats1 was mainly cytoplasmic. These data indicate that Hippo Kinase pathway is activated in the HCC cell lines, may help the HCC cells to escape apoptosis and could be an important target in treatment of primary as well as metastatic HCC.
Bioprobe‐assisted In Vivo dissection of molecular signaling by Rho GTPases in developing neurons
Authors: Chiba Akira
Published: June 2021

Knowing when and where a given signaling protein is normally activated within individual cells and tissues of intact animals permits elucidating its in vivo functions. However, tools for non‐invasive and quantitative visualization are lacking. Here, using genetically encoded A‐probe (activation bioprobe) designed for Cdc42 GTPase, I show that Drosophila embryos maintain Cdc42 activities at low levels until hour 15:00 of embryogenesis. Within the nervous system where Cdc42 activity first becomes upregulated, individual neurons display precise spatiotemporal patterns of activation restricted to specific ~10 µm compartments. At both organismal and cellular levels, Cdc42's endogenous activation patterns in wild type allow predictions of where loss‐of‐function phenotypes emerge in cdc42/cdc42 mutants. Genetic tests within neurons further support the importance of suppressing endogenous Cdc42 activities until needed in particular compartments. Thus, bioprobe‐assisted analyses uncover how potent, ubiquitously expressed signaling proteins control normal cellular events through intricate regulation of their activities within an intact animal.
Cross‐sectional human anatomy: an interactive electronic approach
Authors: Wineski Lawrence E. , Brown Ramon , Williams Jarrett , Williams Virgil , May Christopher , Sealand Rebecca
Published: June 2021

Many biomedical curricula promote self directed learning as a fundamental instructional methodology. Thus, as students spend more time outside the traditional lecture‐based classroom, there is an increasing need for tools that supplement textbooks and lectures to aide independent learning. We have developed a computer‐based, interactive program in cross‐sectional anatomy that offers faculty a way to structure and deliver core information while simultaneously allowing students individual flexibility in pacing their studies and managing schedules. The material is presented through a series of labeled digital images of cadaver cross sections, CT's, and MRI's. Menus allow the user to study the images by anatomical region. Each cross‐section is available as a gross sectional image and a corresponding radiographic image. The program includes a strong emphasis on self‐testing. A "labels on" and "labels off" feature for each image allows review and self quizzing. Further, there is a "drag and drop" test feature that allows the user to drag an answer from a randomized list of terms and drop it on the appropriate location on the image. Additional self‐testing includes NBME‐style questions with clinically based vignettes centered on the cross‐sectional images. Future development will include more advanced self‐testing media and score tracking mechanisms. (Supported in part by NIH PO3 1B040107 and G12‐RR 03034)
The Paradoxical Dynamism of Marrow Stem Cells
Authors: Quesenberry Peter J. , Aliotta Jason M.
Published: June 2021

Marrow stem cell regulation represents a complex and flexible system. It has been assumed that the system was intrinsically hierarchical in nature, but recent data has indicated that at the progenitor/stem cell level the system may represent a continuum with reversible alterations in phenotype occurring as the stem cells transit cell cycle. Short and long‐term engraftment, in vivo and in vitro differentiation, gene expression, and progenitor numbers have all been found to vary reversibly with cell cycle. In essence, the stem cells appear to show variable potential, probably based on transcription factor access, as they proceed through cell cycle. Another critical component of the stem cell regulation is the microenvironment, so‐called niches. We propose that there are not just several unique niche cells, but a wide variety on niche cells which continually change phenotype to appropriately interact with the continuum of stem cell phenotypes. A third component of the regulatory system is microvesicle transfer of genetic information between cells. We have shown that marrow cells can express the genetic phenotype of pulmonary epithelial cells after microvesicle transfer from lung to marrow cells. Similar transfers of tissue specific mRNA occur between liver, brain, and heart to marrow cells. Thus, there would appear to be a continuous genetic modulation of cells through microvesicle transfer between cells. We propose that there is an interactive triangulated Venn diagram with continuously changing stem cells interacting with continuously changing areas of influence, both being modulated by transfer of genetic information by microvesicles.
Calculating the permanent lifestyle changes required for weight‐loss maintenance
Authors: Hall Kevin D , Jordan Peter N
Published: June 2021

Lifestyle changes can successfully induce weight loss in obese individuals, at least temporarily. But there is presently no way to quantitatively estimate the permanent changes of diet or physical activity required to prevent weight regain. Such a tool would be helpful for goal‐setting since obese patients and their physicians could assess whether adherence to the calculated lifestyle change is realistic. To address this issue, we developed a mathematical model to calculate the body weight change arising from a given energy intake change, and conversely, the modification of energy intake required to maintain a particular body weight change. We used data from 8 longitudinal weight loss studies representing 157 subjects with initial body weights ranging from 68‐160 kg and stable weight changes between ‐7 and ‐54 kg. Model calculations closely matched the weight change data (R2 = 0.83, χ2 = 2.1, p < 0.01 for weight changes, R2 = 0.91, χ2 = 0.87, p < 0.0004 for energy intake changes) and also accurately predicted the proportion of weight change resulting from the loss of body fat (R2 = 0.90). Therefore, our model provides the first realistic calculations of lifestyle modifications required for weight loss maintenance. Standard spreadsheet files of the model can be freely downloaded at http://www2.niddk.nih.gov/NIDDKLabs/LBM/lbmHall.htm and can therefore be widely used by physicians and weight management professionals.
Mediterranean diet, weight loss and features of the metabolic syndrome
Authors: Richard Caroline , Charest Amélie , Couture Patrick , Lamarche Benoît
Published: June 2021

The objective of this study was to examine the efficacy of the Mediterranean diet (MedDiet) under optimally controlled conditions, with and without weight loss, on the cardiometabolic risk profile of male patients with the metabolic syndrome (MetS). Twenty‐six men aged between 24 to 62 years with the MetS (NCEP‐ATP III) consumed a North American control diet for 5 weeks followed by a 5‐week MedDiet, both under weight‐maintaining conditions. They then underwent a 20‐week weight loss phase, after which they consumed the weight stabilizing MedDiet for the second time. All foods were provided to participants during the isocaloric phases of the study. The MedDiet without weight loss decreased total plasma cholesterol (C), LDL‐C and the total/HDL‐C ratio by 7.1%, 9.3% and 6.5% respectively, compared to the control diet (all p<0.05). Body weight was reduced by 8.2% and waist circumference by 8.0 cm during the weight loss phase (p<0.001). The MedDiet with weight loss reduced systolic blood pressure (‐4.6%), diastolic blood pressure (‐9.5%), triglyceride (‐16%), apoB (‐10%) and fasting glucose (‐6.0%) compared to the control diet (all p<0.03).

Conclusion

The MedDiet leads to significant changes in plasma cholesterol concentrations but weight loss appears to be required for the MedDiet to modify the cardiometabolic risk factors associated with the MetS. Financial support: Canadian Institutes for Health Research.
Safety and Efficacy of Protein‐Enriched Meal Replacements over 12 months
Authors: Li Zhaoping , Treyzon Leo , Chen Steve , Hong Kurt , Yan Eric , Kim Woosung , Carpenter Catherine , Thames Gail , Bowerman Susan , Wang He‐Jing , Elashoff Robert
Published: June 2021

Since there has been concern over the use of high protein meal replacements for obesity due to potential effect on liver, renal function, and bone metabolism, the present double‐blind randomized controlled trial was conducted in 100 obese subjects who were randomly assigned to receive either standard protein (SP) (0.5 g per pound lean body mass) or high protein (HP) (1.0 g per pound lean body mass) with a diet plan designed to provide a 500 Calorie deficit per day. Subjects were instructed to mix a soy/whey protein powder (Performance Protein Powder, Herbalife) or a non‐protein isocaloric carbohydrate powder (control) with a standard meal replacement (Formula 1, Herbalife). Meal replacements were taken twice a day with one meal for 3 months and then one a day for 9 months. 75 subjects completed the 1 year study and subjects in both groups lost weight (HP ‐4.05 ± .83 kg vs. SP ‐4.42 ± 1.12 kg, p<0.05). There was no difference between groups in weight loss. Liver functions including AST, ALT, Bilirubin, Alkaline Phosphatase were in the normal range and did not change significantly. Similarly, 24 hour urine collections for creatinine, albumin, and calcium secretion did not change from baseline and were not different between groups. Bone mineral density by DEXA did not change in either group over one year. These studies demonstrate that protein‐enriched meal replacements are safe and effective for weight loss over one year.
Can the alternate healthy eating index (AHEI) score predict health outcomes for Cuban Americans with and without type 2 diabetes?
Authors: Huffman Fatma G , McNamara Elizabeth , Zarini Gustavo G.
Published: June 2021

Adherence to a dietary pattern represented by the AHEI has been inversely correlated with CVD incidence in healthy populations. The population with type 2 diabetes (T2D) is at particularly high risk for CVD. Determining a dietary pattern successful in decreasing CVD risk in the diabetic population will enable more specific dietary recommendations. The relationship between AHEI score and 10‐year coronary heart disease (CHD) risk in Cuban Americans (n=367) with and without T2D. Subjects were randomly recruited from a mailing list in Miami‐Dade and Broward Counties, FL. AHEI score was calculated from self‐reported FFQ; CHD risk was determined using ATPIII's 10‐year Risk Calculator. AHEI score was evaluated against the presence of CHD risk. Analyses included descriptive statistics, correlations, and linear regressions controlling for BMI, WC and physical activity. Mean AHEI scores for diabetics and non‐diabetics were 33.00±10.77 and 33.95±11.26 respectively. There was a significant inverse correlation (r=‐.14, p=.008) between AHEI and CVD risk. However, linear regression models found AHEI to be a significant predictor of 10‐year CVD risk only among diabetics (p=.001). Diabetic with higher AHEI scores had lower scores for 10‐year risk of CVD, therefore dietary guidelines for individuals with T2D that include patterns representing a high AHEI score are warranted.
Pleurotus ostreatus suppresses food‐borne carcinogen‐ and inflammation‐induced colon carcinogenesis and inhibits endotoxemia in mice
Authors: Sliva Daniel , Jedinak Andrej , Jiang Jiahua , Dudhgaonkar Shailesh
Published: June 2021

The association among diet, colon cancer risk and mortality is well established, and epidemiological studies suggest that mushroom intake may prevent the development of cancer. In the present study we evaluated whether edible osyter mushroom (Pleurotus ostreatus) affects the development of food‐borne carcinogen‐ (2‐amino‐1‐methyl‐6‐phenylimidazo [4‐5‐b] pyridine, PhIP) and inflammation‐ (dextran sodium sulfate, DSS) induced colon carcinogenesis in mice. Here we show that an oral administration of P. ostreatus extract (POE) for 16 weeks (3 times per week at 0, 100 and 500 mg/kg of body weight) significantly decreased the PhIP/DSS‐induced formation of colonic tumors, and reduced the numbers of aberrant colonic crypts in a dose‐dependent manner. Anti‐inflammatory properties of the oyster mushroom were evaluated in macrophages treated with P. ostreatus powder (POP). Thus, POP suppressed LPS‐induced secretion of TNF‐α, IL‐6, IL‐12p40, and nitric oxide (NO), and down‐regulated expression of iNOS and COX‐2 in RAW264.7 cells. These effects were mediated by the inhibition of AP‐1 but not NF‐κB activity in macrophages challenged with LPS. Finally, POP suppressed LPS‐induced secretion of TNF‐α and IL‐6 in the endotoxemia mice model. In summary, our data suggest that the dietary oyster mushroom can be used for the prevention against colon carcinogenesis and inflammation.
Anti‐inflammatory Actions of Oat Beta Glucans in an Exercise Stress Model
Authors: DiSilvestro Robert A , Creamer Jennifer
Published: June 2021

Beta glucans are dietary fiber but some goes intact into circulation. This could generate systemic anti‐inflammatory actions. In young adult men, beta glucans (3 g/d, 4 wk) as oat bran (Oatvantage(tm)) decreased exercise‐induced inflammation based on soreness perception. The result was not duplicated by a low fiber placebo. Inflammation was induced by a single leg extension protocol done before and after the 4 wk intervention. Soreness in the beta glucan group fell by 1.4 on a 10 point scale from pre‐ to post‐intervention, while the placebo group's soreness rose by 0.4. In addition, serum myeloperoxidase, a marker of inflammation, rose significantly after exercise pre‐intervention in the beta glucan group, but not at post‐intervention. Beta glucans intake also decreased an exercise effect on serum malondialdehyde, a marker of oxidant stress that can be associated with inflammation. These results show that beta glucans can blunt lipid peroxidation and inflammation caused by exercise, while decreasing soreness post‐exercise. Further work should be done to see if beta glucans can exert other anti‐inflammatory effects, including those relevant to cardiovascular disease.
Arginine‐Mediated Stimulation of Intestinal Epithelial Cell Protein Synthesis Is mTOR‐Dependent But NO‐Independent
Authors: Bauchart‐Thevret Caroline , Cui Liwei , Stoll Barbara , Burrin Douglas
Published: June 2021

Arginine (ARG) is an indispensable amino acid in neonates and required for growth. Evidence indicates that intestinal epithelial cells (IEC) are capable of ARG transport, catabolism and synthesis, and express nitric oxide synthase (NOS) to produce NO from ARG. Our aim was to determine whether ARG directly stimulates IEC proliferation, survival and protein synthesis and whether this effect is NO‐dependent and mediated via mammalian target of rapamycin (mTOR). Neonatal porcine IEC (IPEC‐J2) were cultured in a serum‐free Dulbecco's Modified Eagles Medium (DMEM) without ARG. After 4‐d incubation, we found an increase in cell number (+175%), cell protein (+75%) and DNA content (+50%) with a maximal response at a physiological dose of ARG (0.1 mM). The expression of inducible NOS in IPEC‐J2 cells was confirmed by western blot. The ARG‐induced protein synthesis response was not inhibited by NO inhibitors (L‐NAME or aminoguanidine). Protein synthesis was not increased by addition of a NO donor (SNAP) or the ARG precursor, proline in absence of ARG. However, ARG‐induced protein synthesis was markedly decrease (‐40%) by rapamycin, an inhibitor of mTOR. We also found ARG (0.5 mM) increased phospho and total mTOR and p70S6 kinase level in IPEC‐J2 cells. We conclude that ARG‐mediated stimulation of IEC protein synthesis is m‐TOR‐dependent but NO‐independent. (Funded by Ajinomoto Amino Acid Research Program).
mTOR, AMPK and GCN2 coordinate the adaptation of hepatic energy metabolic pathways in response to amino acids and insulin.
Authors: Tomé Daniel , Chotechuang Nattida , Azzout‐Marniche Dalila , Chaumontet Catherine , Bos Cécile , Gausserès Nicolas , Gaudichon Claire
Published: June 2021

This study addressed the question of amino acid sensing in hepatocytes. We investigated the influence of amino acid mixture and insulin on the phosphorylation state of mammalian target of rapamycin (P‐mTOR), adenosine monophosphate‐activated protein kinase (P‐AMPK) and general control non depressible 2 kinase (P‐GCN2)in primary culture of hepatocytes. The activation of protein translation required both high AA levels and insulin, as indicated by the increase in 4E‐BP1 phosphorylation (Pƒ¬0.01). This was associated with an increase in P‐mTOR and a reduction of the activity of P‐AMPK and P‐GCN2 (Pƒ¬0.01) suggesting, for the first time, that GCN2 is involved in sensing amino acids increase. In order to examine whether 4E‐BP1 is the down stream target of mTOR, hepatocytes were incubated in the presence or absence of AICAR or Rapamycin. Surprisingly, no change in p4E‐BP1 was observed in the presence of Rapamycin whereas p4EBP‐1 was dramatically decreased by AIRCAR. This suggested that in response to AA and insulin 4E‐BP1 is not the direct downstream target of mTOR and that AMPK may be involved in this effect.
Body mass index, eating attitudes and behaviors, body image and physical activity in young Caucasian and Asian Canadian women
Authors: Barr Susan Irene , Bedford Jennifer Lynn
Published: June 2021

The effect of ethnicity on associations among Body Mass Index (BMI), eating attitudes, body image and physical activity is not straightforward, and few studies have assessed differences between Caucasians and Asians. To explore this, we recruited 51 Caucasian and 52 Asian (Chinese) healthy female university students living in Vancouver. Height and weight were measured and body fat assessed by dual‐energy x‐ray absorptiometry. Questionnaires were used to assess eating attitudes, body image, physical activity and energy intake (food frequency questionnaire). Compared to Asians, Caucasian women had similar energy intake (1778±633 vs 1759±713 kcal) and % body fat (28.3±6.4% vs 27.3±5.3%) but higher BMI (22.4±2.6 vs 20.9±2.0 kg/m2, p<0.01). Caucasians were more active (Baecke physical activity score 9.0±1.6 vs 7.5±1.5, p<0.001) and were more likely to report a current weight loss effort (46% vs 23%, p<0.05). However, Asian women had significantly higher scores (indicating greater dissatisfaction or more disordered eating attitudes) on the Beliefs About Appearance Scale (44.2±13.9 vs 38.5±13.6) and the Eating Disorders Inventory subscales for bulimia (13.8±4.5 vs 11.7±2.9), drive for thinness (19.8±6.6 vs 16.4±6.1) and body dissatisfaction (31.6±7.7 vs 27.4±10.0). With BMI as a covariate the size of these differences increased, and differences in scores on the Body Shape Questionnaire and the cognitive dietary restraint subscale of the Three‐Factor Eating Questionnaire became significant. Despite lower relative weight among Asian Canadian women, eating‐ and body image‐related concerns are common. Supported by CIHR MOP 79563.
Instrumental variable analysis to adjust for non‐compliance to randomized dietary interventions: An application to protein intake and bone health in adults
Authors: Thorpe Matthew P , Layman Donald K , Evans Ellen M
Published: June 2021

Non‐compliance in randomized controlled trials (RCT) dilutes estimated treatment efficacy under intent‐to‐treat analysis (ITT), producing an overly conservative statistic. ITT is preferred to as‐treated analysis, where treatment actually received is subject to confounding related to non‐compliance. Another approach, instrumental variable (IV) analysis, is gaining acceptance in clinical trial analysis but is not commonly applied to dietary interventions. We use a RCT of dietary protein and bone health to explore benefits and limitations of IV analysis. Patients (n = 73) were randomized to weight loss diets providing 1.4 (PRO) or 0.8 (CHO) g/kg·d protein. Compliance was monitored by weekly 3d weighed food records. Change in total hip bone mineral density (BMD) as a percent of baseline, measured by dual X‐ray absorptiometry, was compared at 1 year. IV analysis was applied using two‐stage least squares regression. Based on ITT analysis, random assignment to PRO (without respect to compliance) caused (B±SE) 1.36±0.59% (p=0.023) improvement in BMD compared to CHO. IV analysis estimated this value at 1.51±0.63% (p=0.019). Accounting for non‐compliance using an IV approach resulted in an 11% increase in estimated efficacy of treatment. IV analysis provides unbiased estimates of efficacy, corrected for non‐compliance, in the interpretation of RCTs. Discussion of logic and implementation of IV analysis follows.

Grant Funding Source

Illinois Council on Food and Agricultural Research
Dietary Supplements Protect Retinal Pigment Epithelial Cells From Hyperglycemic Damage
Authors: Lin Dingbo , Zhang Yunong , Medeiros Denis M
Published: June 2021

Objective

To determine the protective effects of wolfberry on hyperglycemic damage in retinal pigment epithelial cells.

Methods

Human retinal pigment epithelial ARPE‐19 cells were treated with 36 mM glucose for 60 hrs, with or without 1 mg/mL crude wolfberry extracts. PKCgamma activation was determined by enzyme activity assay. Gap junction activity was determined by scrape loading/dye transfer assay. Western blotting was used to determined activation of AMP‐activated protein kinase (AMPK), acetyl‐CoA carboxylase (ACC), and apoptosis‐inducing factor (AIF).

Results

High glucose‐activated PKCgamma phosphorylated Connexin 50 (Cx50) and Cx57 on serines, and subsequently inhibited gap junction activity. Wolfberry extracts abolished the effects of high glucose on PKCgamma activation. Application of wolfberry extracts abolished the inhibitory effect of high glucose on AMPK activation, completely restored ACC phosphorylation by AMPK, and inhibited AIF translocation out of mitochondria.

Conclusions

High glucose‐induced AIF‐dependent apoptosis would be protected by application of wolfberry extracts through restoration of cellular gap junctional communication and rebalance of cellular energy homeostasis.