bluuebunny/crossref_metadata_2025 huggingface dataset:
Elevated levels of phosphate increase reconstituted thin filament velocity and calcium sensitivity at low pH in an in vitro motility assay
Authors: Debold Edward P , Longyear Thomas J , Turner Matthew A , Davis Jonathan P , Lopez Joseph J
Published: June 2021

During muscle fatigue elevated levels of phosphate (Pi) and hydrogen ions (H+) are thought to inhibit the function of the contractile proteins, but the specific mechanisms are unknown. Therefore we studied the impact of Pi and H+ on the velocity‐pCa relationship in a motility assay using isolated myosin and actin filaments reconstituted with troponin (Tn) and tropomyosin. At saturating Ca++ levels (pCa5), decreasing the pH from 7.4 to 6.8 and 6.5 reduced filament velocity, by 47 and 95%, respectively. Filament velocity was also depressed at every submaximal Ca++ level (pCa7 to 5.5) at both pH 6.5 vs 6.8. However, the addition of 30mM Pi significantly attenuated this acidosis‐induced depression in velocity at pH 6.8 and 6.5, and at every submaximal level of Ca++. A Ca++‐sensitizing mutation in the calcium‐binding region of Tn (V43Q) increased the Ca++ sensitivity of velocity in the absence of Pi (6.7±0.1vs. 7.2±0.1), and the effect was even greater in the presence of Pi (7.5±0.1). Now we are determining if this construct, in conjunction with Pi, can fully attenuate the depressive effects of acidosis. Overall these data suggest that elevated levels of Pi and H+ may exert opposite molecular effects on the contractile proteins during fatigue and suggest that structural perturbations may impact these effects.
Dynamic cerebral autoregulation of the posterior cerebral artery after high level spinal cord injury
Authors: Phillips Aaron Alexander , Krassioukov Andrei V. , Ainslie Philip N. , Tzeng Yu‐Chieh , Warburton Darren E.
Published: June 2021

It has been reported that those with high level (e.g., >; T5) spinal cord injury (HLSCI) can tolerate profound hypotension in the absence of syncopal symptoms. Altered dynamic cerebral autoregulation (dCA) may help maintain cerebral blood flow (CBF) and improve tolerance to hypotension. In HLSCI, dCA of the posterior cerebral artery (PCA), which is relevant to syncopal episodes due to its supply arising from arteries perfusing the brainstem (i.e., critical region for maintaining consciousness), has not been investigated. Eight complete HLSCI and eight matched controls (AB) were examined in the upright position. Five‐minute long recordings of spontaneously occurring beat‐to‐beat changes in blood pressure (BP; photoplethysmography) as well as velocity in the middle cerebral artery (MCA) and PCA (transcranial Doppler) were recorded. To provide insight into dCA, transfer function analysis was performed to evaluate coherence, gain and phase of the MCA and PCA in the very low (0.02–0.07 Hz) and low (0.07–0.2 Hz) frequency ranges. In HLSCI, BP‐MCAv coherence was reduced by 33% in both the LF and VLF range, while VLF phase was reduced by 63% (P < 0.05). Similarly, BP‐PCAv coherence was reduced by 48% in the LF and 54% in the VLF range (P < 0.01). These results show that CBF regulation is altered in both the MCA and PCA in those with HLSCI.
Isolation of adipose‐derived stem cells from human breast subcutaneous adipose tissues and their differentiation into beige adipose tissue‐like adipocytes
Authors: Chen Yu‐Jen , Kuo Wen‐Hong , Yang Jui‐Ting , Chen Chih‐Chien , Ding Shih‐Torng
Published: June 2021

A new class of adipose tissue, termed beige adipose tissue (BeAT) has recently been identified to possess distinct origin, properties and function from the other two, white and brown adipose tissues, and implicated in regulating energy homeostasis that may affect metabolic syndrome. In an effort to study nutrient effects on the regulation of adipogenesis and amelioration of metabolic syndrome in humans, we identified BeAT‐like adipocytes differentiated from the human adipose‐derived stem cells (ADSC) isolated from the breast subcutaneous fats of breast cancer patients undergoing mastectomy. The procedure was approved by the Ethics Committee of National Taiwan University Hospital. The stromal‐vascular cells were isolated and maintained according to general procedures. After reaching to confluence and cultured in standard differentiation medium containing rosiglitazone for 15 days, the cells started to accumulated lipid droplets as stained by Oil‐Red‐O under light microscope and the expressions of brown adipose tissue‐or BeAT‐associated genes, such as UCP‐1, PRDM‐16, Tmem26, and CD137, were identified by quantitative real‐time PCR. Our current study, therefore, not only demonstrates that the human breast subcutaneous fat harbors the potential to differentiate into BeAT under adipogenic differentiation procedures, but also creates a novel model system for the study of BeAT and sheds new lights on future design of therapeutic approaches for metabolic diseases and regenerative medicine..
Active expiration and sympathetic overactivity induced by short‐term sustained hypoxia in rats
Authors: Zoccal Daniel B. , Moraes Davi J.A. , Bonagamba Leni G.H. , Costa Kauê M. , Costa‐SIlva João H. , Machado Benedito H.
Published: June 2021

Short‐term sustained hypoxia (SH, 24 hrs) produces changes in the respiratory motor activity. However, the neurochemical and electrophysiological basis of these changes are poorly understood. In the present study, we evaluated the central mechanisms underlying the respiratory changes induced by SH (10% O2) and the correlated changes in sympathetic activity. Using arterially‐perfused in situ preparations, we observed that SH rats (n=20), but not controls, exhibited late‐expiratory (late‐E) bursts in abdominal nerve (P<0.05) associated with depressed post‐inspiratory and increased augmenting‐expiratory activities of neurons in the Bötzinger complex (BötC, P<0.05). SH rats also exhibited additional late‐E bursts in thoracic sympathetic activity associated with larger Traube‐Hering wave amplitudes (P<0.05). Corroborating these findings, we observed in unanesthetized rats that the arterial pressure levels of SH rats (n=7) exhibited augmented low‐and high‐frequency variabilities (P<0.05). Besides, the antagonism of ionotropic glutamate receptors in the BötC eliminated the late‐E activity in respiratory and sympathetic nerves. Our data indicate that short‐term SH alters the expiratory pattern and its coupling with sympathetic nervous system by mechanisms involving changes of neuronal activities and glutamatergic transmission in the BötC.
Intracellular ATP modulates vascular distinctive P2X receptors in rat arterial smooth muscle
Authors: Morita Hiromitsu , Yoshimoto Shohei , Takeuchi Hiroshi , Abe Kihachiro , Hirata Masato , Ito Yushi
Published: June 2021

The extracellular nucleotide sensitive P2 receptor comprises two different groups: ionotropic P2X and metabotropic P2Y receptors. It is generally considered that the P2X receptor lacks intracellular ATP binding sites.

In rat arterial myocytes, however, we identified that P2X1 and 5 receptors form a heteromultimer and found that its activation kinetics is modulated by cytosolic ATP, since a significant decrease was observed in desensitization of P2X receptor current evoked by repeated application of α,β‐methylene ATP (10μM) at 5 minute intervals with increasing intracellular ATP concentration (0, 2 and 5mM to 52.4±6.0%, 45.7±5.4% and 33.5±3.0%, respectively: n=5–13). In contrast, ADP and AMP did not modulate the current. Similar effects were observed in rat cerebral and mesenteric artery myocytes.

Therefore, we performed a homology search for ATP‐binding motifs in P2X receptors, and found P2X1 and 5 receptors have the motifs at the pore‐forming transmembrane regions. In addition, we confirmed the co‐localization of P2X1 and 5 receptor proteins in each arterial tissue by RT‐PCR, western blot and immunostaining analyses.

These results suggest that P2X1 and 5 receptors may play important roles in metabolic regulation in conditions such as hypoxia.
Analysis of high altitude cognitive task performance on multiple tests
Authors: Issa Amine N , Wentz Robert J , Herman Nicole M , Taylor Bryan J , Summerfield Doug T , Kasak Alexander J , Johnson Bruce D
Published: June 2021

Background

It is documented that cognitive performance can diminish with altitude, but the sensitivity of specific tests have not been investigated. Our objective was to assess and compare cognitive performance from several tests and relate this to quality of sleep and acute mountain sickness (AMS).

Methods

During an Everest expedition, 3 cognitive tests (Stroop, Trail Making, and a proprietary motor accuracy test) were used along with a questionnaire to assess sleep and AMS. Six athlete climbers and 9 core team members were assessed pre and post‐expedition and at several time points during the expedition (up to 17,500 ft).

Results

To normalize for individual differences, scores were assessed as % change from baseline. There was no difference in the variation between repeated attempts in a single testing session (0.19<p<0.87), demonstrating that each test was reproducible. There was no decrement in test scores with altitude, nor was there an association with reported sleep quality. The Stroop performance was associated with AMS (p<0.05) and trending with headache (p< 0.15). The in‐house motor test trended towards an association with AMS and headache (p<0.15). However, the trail making test was not associated with AMS/headache.

Conclusion

With appropriate acclimatization, cognitive performance is maintained at altitude but is linked to presence of headache and AMS. Mayo Clinic and TNF.
Ca2+‐induced mitochondrial permeability transition pore opening is substrate‐dependent
Authors: Aldakkak Mohammed , Stowe David F , Camara Amadou KS
Published: June 2021

Mitochondrial permeability transition pore (mPTP) opening is a key event in ischemia and reperfusion (I/R) injury. Several factors modulate mPTP opening, of which the increase in mitochondrial free Ca2+ plays a critical role. During I/R, there is a substrate switch in mitochondria and it is not known with certainty if/how substrate conditions influence mPTP opening. Hence, we investigated Ca2+‐induced mPTP opening by monitoring Ca2+ retention capacity (CRC) under different substrate conditions. Guinea pig heart mitochondria were suspended in respiration media containing rhodamine 123 or indo‐1 to monitor changes in ΔΨ or extra matrix [Ca2+], respectively. Either pyruvate or succinate was added first, followed by continuous infusion of CaCl2. ΔΨ became depolarized at 275±25 s or at 687±37 s with pyruvate or succinate, respectively. Indo‐1 experiments showed mitochondrial Ca2+ release in the buffer that paralleled ΔΨ depolarization. Adding cyclosporine A prolonged CRC with both substrates indicating that ΔΨ depolarization and Ca2+ release were due to mPTP opening. It is widely accepted that mPTP opening occurs upon reperfusion due to normalization of cytosolic pH. However, our results suggest a role for the complex I substrate pyruvate in Ca2+‐induced mPTP opening and thus, mitochondrial utilization of succinate during reperfusion may prove beneficial against mPTP opening.
NO regulation of Na,K‐ATPase in ocular ciliary epithelium involves Src Family Kinase
Authors: Shahidullah Mohammad , Mandal Amritlal , Wei Guojun , Delamere Nicholas A
Published: June 2021

The nitric oxide (NO) donor SNP reduces aqueous humor (AH) secretion in the isolated porcine eye. SNP inhibits Na,K‐ATPase activity in AH‐secreting tissue, nonpigmented ciliary epithelium (NPE), through a cGMP/PKG‐mediated pathway. Here we study the role of Src family kinases (SFKs) in the Na,K‐ATPase activity response to NO.

NPE was cultured and Na,K‐ATPase activity measured by quantification of ATP hydrolysis in NPE lysate and by estimating ouabain‐sensitive potassium (86Rb) uptake in intact NPE. Protein phosphorylation was examined by western blot.

SNP inhibited Na,K‐ATPase activity by >;35% but did not change Ser16 phosphorylation of the Na,K‐ATPase α1 subunit or the abundance of α1 protein available for surface biotinylation. The SFK inhibitor PP2 prevented both SNP and 8‐Br‐cGMP‐induced reduction of Na,K‐ATPase activity. SNP and 8‐Br‐cGMP increased phosphorylation of SFK, ERK1/2 and p‐38 MAPK. PP2 prevented the responses. The ERK1/2 inhibitor U0126 prevented SNP‐induced ERK1/2 and p‐38 phosphorylation but did not suppress SNP‐induced SFK phosphorylation or Na,K‐ATPase activity reduction. SNP caused detectable phosphorylation of Na,K‐ATPase α1 at Tyr10.

NO‐induced inhibition of Na,K‐ATPase activity appears to depend on SFK activation that occurs via cGMP/PKG.

Funding: NIH Grant EY006915.
Glycan binding protein galectin‐3 negatively regulates UT‐A1 urea transport activity by impairing protein membrane expression
Authors: Li Xuechen , Yang Baoxue , Fröhlich Otto , Hughey Rebecca P , Chen Guangping
Published: June 2021

Galectins, a group of small lectin‐like proteins that bind â‐galactose‐enriched glycoconjugates, play many important roles in membrane protein regulation. By using a panel of GST‐conjugated galectin proteins (galectin‐1, 3, 4, 7, 8, and 9), we performed GST pulldown assays and found galectin‐3 could directly bind to urea transporter UT‐A1 from kidney inner medulla (IM). Northern blot analysis shows galectin‐3 highly expressed in IM, less in OM, and very low in cortex. Cell surface biotinylation shows galectin‐3 cell membrane expression in HEK293 cells. By sucrose density ultracentrifugation, we found that galectin‐3 is localized in lipid raft subdomains. Functional study by co‐injection of galectin‐3 with UT‐A1 cRNAs in Xenopus oocytes shows that galectin‐3 causes a reduction of UT‐A1 urea transport activity. To explore the possible mechanism of galectin‐3 downregulation of UT‐A1, we did cell surface biotinylation and found that overexpression of galectin‐3 in UT‐A1 HEK392 cell reduces UT‐A1 membrane expression. Our study suggests that association with galectin‐3 may represent a novel mechanism for UT‐A1 regulation.
VAMP3 mediates NKCC2 trafficking in thick ascending limbs and is required for normal renal function and blood pressure
Authors: Caceres Paulo S , Haque Mohammed Z , Ortiz Pablo A
Published: June 2021

In the thick ascending limb of Henle's loop (TAL), trafficking of NKCC2 into the apical membrane is essential for NaCl absorption and blood pressure control. The vesicle associated membrane protein 3 (VAMP3), a membrane fusion protein of the SNARE family, is expressed in the kidney. VAMP3 is localized apically in TALs and co‐immunoprecipitates with NKCC2. The role of VAMP3 on Na excretion and NKCC2 trafficking is unknown. We hypothesized that VAMP3 mediates NKCC2 exocytic delivery and maintains normal TAL function and renal Na excretion. We used adenovirus‐mediated in vivo gene silencing to decrease VAMP3 expression in rat outer medullas and measured NKCC2 exocytic delivery by surface biotinylation in TAL suspensions. Silencing VAMP3 by 68 ± 10% did not affect VAMP2/7/8 expression in TALs but blocked NKCC2 exocytic delivery rate by 91 ± 6% (p<0.05) and decreased total NKCC2 expression by 59 ± 8% (p<0.05). We studied the role of VAMP3 in urinary Na (UNa) excretion and blood pressure in VAMP3 knockout (KO) mice. VAMP3 KOs exhibited reduced NKCC2 expression by 44 ± 12% (p<0.05), elevated UNa excretion (wild type: 251 ± 11 vs VAMP3 KO: 294 ± 13 μmol/day, p<0.05) and lower systolic arterial pressure (WT: 114 ± 2 vs VAMP3 KO: 95 ± 2 mmHg, p<0.05). We conclude that VAMP3 mediates NKCC2 trafficking to the apical membrane and maintains NKCC2 expression. VAMP3 is required for normal Na excretion and blood pressure control. Funding: NIH, AHA
Molecular mechanism of chlorine induced lung hyperreactivity in mice
Authors: Lazrak Ahmed , Yu Zhihong , Komarova Svetlana , Doran Stephen F , Garantziotis Stavros , Matalon Sadis
Published: June 2021

Chlorine (Cl2) inhalation causes airway resistance and hyperreactivity (AHR) that lead to asthma‐like symptoms. When inhaled, Cl2 reacts with, and damages, hyaluronan a constituent of the cellular matrix causing the release of low molecular weight fragments (lowHA <300 kDa) which initiate a series of pro‐inflammatory events. Exposure of mice to 400 ppm Cl2 for 30 min caused an increase of lowHA and Inter‐alpha‐trypsin‐inhibitor (IaI) in the BAL 30 min post exposure which peaked at 24 hours; an increase of airway resistance following challenge with methacholine, measured by flexiVent, was observed at 24 h post exposure. Intratracheal administration of an antibody against IaI or high molecular weight hyaluronan decreased AHR, suggesting the involvement of CD44 receptors. Exposure of Human Airway Smooth muscle cells to 100 ppm Cl2 for 10 min caused RhoA activation and membrane potential depolarization that was partially reversed by preincubation with a RhoA inhibitor, and totally abolished with 10 μM Lanthanum. We conclude that Cl2 generated reactive species in the ELF and lowHA‐IaI complexes activate RhoA and Ca2+ channels of airway smooth muscle cells increasing their contractility and thus causing AHR. Supported by NIH grant 5U01ES015676
Kidney blood flow modeled from structural morphology of renal vasculature in the rat
Authors: Bukowy John , Mescam Muriel , Cowley Allen W , Beard Daniel A
Published: June 2021

The kidney extracts and excretes urea and other metabolic wastes from the blood, and maintains levels of plasma salt and hydrogen ions by differentially regulating the concentration of these ions in the urine. Since solute and water transport in the kidney is tied to the control and distribution of flow in the vasculature of the kidney, an understanding of renal microcirculatory dynamics is needed to understand the physiological function of this organ.

Using dimensional and ordering data obtained from a microtomography (Micro‐CT) study of structural morphology of renal vasculature, separate functions describing the transit time distribution of blood flow through the arterial and venous trees were derived. Separately, three regional microcirculatory models (cortical, juxtamedullary, and shunting) were used to connect the arterial and venous trees. Simulation of the combined model yields a renal intravascular washout function that describes the transit of blood throughout the kidney. Using optimization methods, simulations were fit to experimental data obtained from rat kidney washout studies to estimate functional blood flow to the three microcirculatory beds. This modeling approach can be applied to analyzed data from imaging modalities using contrast measurements in animal studies as well as the clinical setting.
Tendon collagen fibrils ‐ Continuity and mechanical properties
Authors: Svensson Rene Brüggebusch , Herchenhan Andreas , Kovanen Vuokko , Qvortrup Klaus , Magnusson S. Peter
Published: June 2021

Purpose

Tendon force transmission depends on the length and mechanical behavior of collagen fibrils, two poorly understood parameters.

Methods

Collagen fibrils from rat‐tail tendons (RTT) and human patellar tendons (HPT) were mechanically tested to failure using atomic force microcopy (AFM). The effect of cross‐link stabilization by NaBH4 in RTT was investigated. Continuity and structure of HPT fibrils was determined by electron microscopy serial sectioning (FIB‐SEM).

Results

Failure stress and high‐strain modulus were greater for the HPT (540±140 MPa, 4.3±1.4 GPa) than RTT fibrils (200±110 MPa, 1.4±0.7 GPa) (p<0.001) (see fig.). NaBH4 had no effect on RTT fibril mechanics. In contras, fascicles showed higher failure stress (58±18 MPa vs 35±11 MPa, p=0.02) and reduced failure strain (5.0±0.8% vs 9.7±4.5%, p=0.05). A total of 1800 HPT fibrils were traced through 25μm deep FIB‐SEM stacks (total length = 45 mm), and only one fibril end, 4 fibril fusions and 3 fibril loops were observed.

Conclusion

Differences between RTT and HPT fibril properties are likely caused by greater cross‐link maturity in HPT, but seem unrelated to cross‐link lability since NaBH4 had no effect on RTT fibrils. That reduction did have an effect at the fascicle level indicates the presence of reducible interfibrillar bonds. HPT fibril length data suggests that fibrils rarely end, but rather fuse to form a functionally continuous structure.
Obstetrical practices but not gestational metabolic abnormalities are associated with delayed onset of lactogenesis
Authors: Ley Sylvia H , Hanley Anthony J , Zinman Bernard , O'Connor Deborah L
Published: June 2021

Women with pre‐existing diabetes and obesity experience delayed onset of lactogenesis II (DOLac), but the impact of metabolic abnormalities developed during pregnancy on DOLac is unclear. We aimed to investigate the associations of metabolic status assessed during pregnancy with DOLac (onset of lactogenesis II ≥72 h postpartum). Participants (n=177) underwent a 3‐h oral glucose tolerance test at 30 (25th, 75th %tile: 29, 32) weeks gestation, and follow‐up interviews were conducted at 1, 3, and 7 d postpartum. Of 177, 98 (55.4%) women experienced DOLac. Gestational metabolic abnormalities, including gestational diabetes, insulin resistance (HOMA‐IR) and lower insulin sensitivity (Matsuda index), were not associated with DOLac. However, risks for DOLac were increased among women who had an unscheduled C‐section (OR 2.24 [95% CI 1.02, 4.92] vs. spontaneous delivery) and delayed initiation of breastfeeding (2.30 [1.09, 4.86] comparing ≤1 vs. >;2 h) with adjustment for age and ethnicity. Further, women who had an unscheduled C‐section put their infant to the breast at 2.0 (25th, 75th %tile: 1.0, 5.1) h, while women who had a spontaneous delivery did so at 1.0 (0.8, 2.0) h. In conclusion, gestational metabolic abnormalities are not associated with DOLac, but obstetrical practices including unscheduled C‐section and delayed timing of breastfeeding initiation increase risk for DOLac.

Funding: CDA, CFDR, CIHR
Consumer attitudes and misconceptions of foods with sodium claims: Results of a randomized mock label experiment
Authors: Wong Christina L. , Arcand JoAnne , Mendoza Julio , Qi Ying , L'Abbé Mary R.
Published: June 2021

In light of the public health priority to reduce dietary sodium, we evaluated consumers’ attitudes and understanding of permitted sodium claims on food labels. Online panellists were exposed to 4 identical mock canned soup labels, in random order, with the same Nutrition Facts table which differed only by the claim it carried. We tested 3 types of sodium claims (nutrient content (NC), function, disease risk reduction (DRR)) and a ‘tastes great’ claim acting as a control. Overall, all sodium claims resulted in higher ratings in attitudes toward the claim (i.e. attractiveness, clarity and credibility), attitudes towards the product (i.e. perceived healthiness) and purchasing intentions compared to the control claim (p<0.001). The NC and DRR claims were consistently rated the highest and similar to each other, yet regulatory criteria for foods to carry such claims differ greatly. Sodium claims, that do not mention health or disease, still infer health benefits. In addition, panelists attributed additional health benefits to products carrying sodium claims, beyond the well established relationship between sodium and hypertension, such as for weight loss, diabetes and constipation (p<0.001). This study demonstrates the need for additional efforts to educate consumers on common misconceptions of the benefits of sodium reduction, especially as population wide sodium reduction initiatives move forward.

Grant Funding Source: AFMNet; CIHR operating grant/Canadian Stroke Network; CIHR Strategic Training Program in Public Health Policy (CW), CIHR Strategic Training in Population Intervention for Chronic Disease Prevention: A Pan‐Canadian Program (Grant#53893) (CW); Ontario Graduate Scholarship (CW); Heart & Stroke Foundation of Canada Postdoctoral Fellowship (JA); University of Toronto McHenry Chair (ML)
Do Registered Dietitians know beans? Knowledge, attitudes & perceptions of the health effects of beans
Authors: Winham Donna M , Hutchins Andrea M.
Published: June 2021

The purpose of the online survey was to assess the knowledge, attitudes and perceptions about the role of dried beans such as pinto, black, or kidney in chronic disease prevention or risk reduction among Registered Dietitians (RDs) in Arizona. Of the 343 completed surveys, most respondents were female (95%), non‐Hispanic White (92%), and personally ate beans at least once per week (72%). A series of Likert scale questions asked about known health effects of beans. Knowledge of the role of beans in LDL cholesterol reduction, satiety, overall nutrition improvement and lowering of postprandial hyperglycemia was high. However, some bean characteristics were less known or incorrect. Over 83% of respondents were unaware that bioavailability interference with mineral absorption was possible. Twenty‐six percent did not know bean consumption alters intestinal bacteria. About 20% were unaware beans were high in folate or that persons with celiac disease could eat beans. Twenty‐seven percent erroneously agreed that beans raise HDL cholesterol. Translation of the evidence‐based health benefits of beans to the public is mediated by the RD. Outreach and education for less known aspects of bean nutrition such as probiotics, celiac disease, and folate content should be increased with this essential group of nutrition professionals.
Predicting satiety responses of cereals in vitro: Oatmeal shows gastric gelling behavior.
Authors: van Klinken Bernardus Jan‐Willem , Chu YiFang , Bordenave Nicolas , Vink Carolien , de Jong Saskia , Ruijschop Rianne , Lambers Tim , Oshea Marianne
Published: June 2021

In a clinical study Standard Quaker Oatmeal (SQO) was significantly more satiating than Honey Nut Cheerios (HNC). In order to investigate mechanism of action in the satiety responses to these selected oat based cereals, two models were used to assess the physic‐chemical properties of cereals under digestive conditions: SIMPHYD (NIZO Food Research) and a viscosity measurement during simulated in vitro starch digestion. SQO, Instant Quaker Oatmeal (IQO) and HNC along with a positive control (alginate) were subjected to the SYMPHYD gelling assay. During simulation of digestion all cereals increased measured forces relative to the positive control. Additionally SQO and IQO immediately gelled in the model compared to HNC, where gastric volume of the solid particles increased over time. Despite a viscosity decrease due to starch digestion of SQO and HNC, SQO viscosity remained significantly higher than HNC viscosity. This suggests that gastric gelling and underlying viscosity due to soluble fiber may be important determinants of the satiating potency of these cereals in addition to the mode of preparation of the cereals. Supported by: PepsiCo R&D
The role of the Rho GTPases in lens placode invagination
Authors: Chauhan Bharesh K , Lou Ming , Troilo Albino , Choi Sue‐Yeon , Scita Giorgio , Zheng Yi , Lang Richard A
Published: June 2021

Epithelial invagination is a central feature of embryonic morphogenesis in animals. Here, we show that RhoA mutant lens placode cells are both longer and less apically constricted than control cells, causing reduced epithelial curvature and reduced invagination. By contrast, Rac1 mutant lens placode cells are shorter and more apically restricted than controls, resulting in increased epithelial curvature and precocious closure of the lens vesicle. Quantification of RhoA and Rac1‐dependent pathway markers over the apical‐basal axis of lens pit cells showed that in RhoA mutant epithelial cells, there was a Rac1 pathway gain‐of‐function and vice versa. These findings suggest that mutual antagonism produces balanced activities of RhoA‐generated apical constriction and Rac1‐dependent cell elongation that controls cell shape and thus the curvature of invaginating epithelium. Previous studies have shown that contractile lens‐specific filopodia, under Cdc42 control, tether to the optic cup during lens placode invagination. Here, we examine the efficacy of lens filopodia in transmitting forces to co‐ordinate lens and retinal shape. Our observations suggest contractile and protrusive forces exerted by lens filopodia aid in shaping the underlying retina, and therefore bring us closer to understanding the important process of tissue co‐ordination for organ functionality.
Development and Implementation of Educational Outreach Programs for Oakland and Neighboring Communities
Authors: Puder Barb , Neal Jasmine
Published: June 2021

Community members are becoming more proactive in their health care decisions, and many individuals are seeking more information regarding the function and maintenance of various body systems, disease prevention, and lifestyle choices that can impact their personal health. In turn, many universities have mission statements and goals to create community connections and provide educational programs on various health related topics. To meet the needs of community and university members, educational outreach programs can be established. Several outreach programs regarding brain health and safety have been created for Oakland area school children in grades K‐12 and an educational brain event for families and community members. The K‐12 outreach programs are designed within the needs of the curriculum content and grade level of the students. Classroom teachers are consulted for topic requests and length (time) of program that fit into their lesson plans and schedules. Programs vary from 1 hour to several hours to a 4 week mini course and cover topics ranging from neuroanatomy to sensory systems to drug effects on the nervous system.

Saturday outreach events are designed to be family friendly and serve to educate both children and adults through interactive hands‐on poster stations presented by university students and lectures by selected invited guest speakers. Assessments from all programs are administered in the form of pre and post tests for K‐12 programs and surveys for participants of the Saturday community educational events.
Controlling genome integrity via post‐translational regulation of the eukaryotic replisome
Authors: Labib Karim
Published: June 2021

The Cdc45‐MCM‐GINS helicase is assembled in situ at nascent DNA replication forks, and then associates stably with forks until replication terminates when one fork meets another. Many other factors including DNA polymerases epsilon and alpha associate with the CMG helicase to form the replisome, which plays a central role in preserving genome integrity during each round of the cell cycle. Assembly of the eukaryotic replisome is regulated extensively by phosphorylation, in contrast to assembly of the analogous replisome in E. coli. It now appears likely that replisome function and disassembly are also regulated by posttranslational modifications that are critically important to preserve chromomosome stability and genome integrity. The principles of replisome regulation are likely to have been highly conserved throughout evolution, so that much can be learnt from single celled species such as yeasts. It now seems clear that replisome function is regulated by phosphorylation, ubiquitylation and sumoylation.
Proteomics and the Control of MAP Kinase Dynamics
Authors: Ahn Natalie , Xiao Yao , Lee Thomas , Warner Lisa , Latham Michael , Tanimoto Akiko , Peti Wolfgang , Page Rebecca , Pardi Arthur
Published: June 2021

Enzyme motions control catalysis through mechanisms that are incompletely understood. Here, we use hydrogen exchange mass spectrometry (HX‐MS) and NMR relaxation to report internal motions in the MAP kinase, ERK2. HX‐MS shows that ERK2 activation by phosphorylation increases conformational mobility at the linker between N‐ and C‐terminal domains. This predicts that domain closure is regulated by phosphorylation, corroborated by showing that ERK2 binds ATP in two modes distinguishable by kinase activity state. Thus, before phosphorylation, ERK2 is constrained from interdomain interactions needed for catalysis, and this is overcome by phosphorylation, via altered linker dynamics. We next performed temperature‐dependent methyl‐Carr‐Purcell‐ Meiboom‐Gill (CPMG) NMR experiments, monitoring side chain motions by chemical exchange between conformational states in 13C‐methyl‐Ile,Leu,Val‐ERK2. CPMG‐NMR shows changes in dynamics between active and inactive ERK2 with kex in the μs‐ms time regime. The side chain motions vary widely in inactive ERK2, but in contrast, a large set of methyl groups share kinetic and thermodynamic properties in active ERK2. The active enzyme undergoes conformational exchange between two wellpopulated (80%/20%) states with kex ~300 s−1. Thus, kinase activation leads to changes in enzyme dynamics, involving concerted motions between residues surrounding the active site.
How does household composition affect purchases of grainbased desserts?
Authors: Mathias Kevin Clark , Ng Shu Wen , Popkin Barry
Published: June 2021

Grain‐based desserts (GBD) (e.g., cakes, cookies and pies) are the largest source of solid fats and the second largest source of added sugars in the US diet. Given that over 70% of GBD are purchased from stores, identifying factors (e.g., composition of children and adults living in a household) that affect household purchases of GBD is essential for decreasing intake of solid fats and added sugars. Quarterly store purchases of ready‐to‐eat GBD from 61,658 households participating in the 2011 Nielsen Homescan panel were analyzed using random effects models. The average purchase of GBD per day was 115 kcal among men living alone, 91 kcal among women living alone, 155 kcal for households with multiple adults and no children, 139 kcal for households with one adult and children, and 178 kcal for households with multiple adults and children. Among households of multiple adults without children, purchases of GBD increased by 19 kcal/additional adult. Among households with one adult and children, purchases of GBD increased by 19 kcal/additional child. Among households of multiple adults and children, purchases of GBD increased by 12 kcal/additional child and 19 kcal/additional adult. These results show that within household categories, increasing the number of individuals does not substantially increase the GBD purchased by a household, indicating that smaller households have larger amounts of GBD available to each person.

Grant Funding Source: Robert Wood Johnson Foundation Grant 70017; National Institutes of Health R01‐HD030880 R01‐ HL104580 R01‐HL114091 R01‐HL108427.
Creatine Supplementation may prevent NAFLD by stimulating fatty acid oxidation
Authors: Jacobs Rene L , da Silva Robin , Nelson Randy
Published: June 2021

Creatine is a naturally occurring metabolite responsible for maintaining ATP levels in tissues with high and rapidly fluctuating energy demands. Recently, we reported the novel and surprising finding that dietary creatine supplementation prevents hepatic steatosis in rats fed a high‐fat diet. The primary goal of this project is to investigate the mechanism by which creatine influences hepatic lipid metabolism. To accomplish this goal we incubated McArdle RH‐7777 hepatoma cells with oleic acid (OA) and creatine. We found that creatine reduces cellular TG levels by 50% (P<0.05). Incorporation of 3H‐oleate into TG was reduced by creatine by 40% (P<0.05). Creatine supplementation resulted in a 2‐fold increase (P<0.05) in 14CO2 production from 14C‐oleate, and a 20% increase (P<0.05) in levels of the ketone body, â‐hydroxybutyrate. To determine whether dietary creatine supplementation can improve liver function in mice susceptible to NAFLD, we fed the liver‐specific CTP:phosphocholine cytidylyltransferase‐α knockout (LCTαKO) and control mice a HFD with or without 1% creatine. After 3 weeks of feeding, creatine supplementation prevented the 3‐fold increase (P<0.05) in hepatic TG in the LCTαKO mice. The data suggests that creatine may be a potential and novel therapy for Non‐Alcoholic Fatty Liver Disease in humans.
Dietary Behavior Modification, With or Without Exercise, Improves Risk Factors for CVD over One Year in Overweight and Obese Lactating Women
Authors: Brekke Hilde Kristin , Bertz Fredrik , Rasmussen Kathleen M , Bosaeus Ingvar , Ellegård Lars , Winkvist Anna
Published: June 2021

Childbearing is associated with increased risk for cardiovascular disease (CVD). Our objective was to examine the effects of Diet (D) and Exercise (E) interventions on cardiovascular fitness, blood lipids, glucose metabolism, cytokines and blood pressure in overweight or obese lactating women using a 2×2 factorial design. At 10–14 wk postpartum, 68 women with a self‐reported prepregnancy BMI of 25–35 kg/m2 were randomized to a 12‐wk behavior modification treatment with D, E, both or control. The goal of D treatment was to reduce body weight by 0.5 kg/wk through reduced energy intake and of the E treatment was to perform 4 45‐min walks/wk at 60–70% of max heart‐rate. Effects were measured post intervention (12 wk) and 9 mo later (1‐y follow‐up). Two‐way ANCOVA was used to study main and interaction effects adjusted for baseline values. The D treatment produced a 1‐y weight loss of 10%. There was a significant main effect of the D treatment, decreasing fasting insulin (P<0.05), total cholesterol (P <0.01) and LDL‐cholesterol (P <0.01) at the end of the 12‐wk treatment. The decreased insulin was sustained (P<0.05) and HDL‐cholesterol increased (P <0.01) at the 1‐y follow‐up. No effects from the E treatment or any interaction effects were observed. Dietary behavior modification produced sustained improvements in risk factors for CVD in overweight and obese lactating women. (Funded in part by the Swedish Research Council.)
Key markers associated with intestinal adaptation in pediatric short bowel syndrome
Authors: Naberhuis Jane Kelly , Tappenden Kelly Anne
Published: June 2021

Administration of partial enteral nutrition (PEN) and trophic peptides, such as glucagon‐like peptide‐2 (GLP‐2), are emerging strategies for stimulating structural and functional aspects of intestinal adaptation in individuals with intestinal failure. To investigate the temporal sequence of events associated with PEN and/or GLP‐2‐mediated intestinal adaptation following massive small bowel resection, neonatal piglets underwent an 80% jejunoileal resection (n=72) and were randomized to 1 of 4 treatment groups using a 2×2 factorial model with total parenteral nutrition (TPN) or TPN+PEN and placebo or GLP‐2. Piglets were euthanized 4h, 48h or 7d after surgery and 93 variables of adaptation were analyzed by principal component analysis (PCA). Maximal variation was accounted for by small intestinal proliferation, apoptosis and crypt depth when all time points were pooled. The main factors accounting for variance shifted from crypt depth at 4h, to small intestinal nutrient transport and cellular proliferation at 48h. By d7, mucosal architecture, epithelial proliferation and nutrient transport accounted for maximal variation. These results indicate that structural markers of adaptations precede those of functional adaptation; however, crypt depth remains a strong indicator, regardless of time.

Grant Funding Source: Internally funded
Identifying plausible energy intake for children who attend child care
Authors: Martin Chantel L , Hales Derek P. , Vaughn Amber P. , Ward Dianne S.
Published: June 2021

Reporting bias is a well‐recognized limitation of dietary recalls. Parent recall of child diet is additionally challenged because parents are often asked to report meals eaten when they are not present. We explored a method for identifying and correcting implausible energy intake (EI) using baseline data from an intervention trial of 324 children, 2–5 years of age. Reported energy intake (rEI) was derived from 2 weekday parent‐reported 24‐hour dietary recalls. Sex‐ and gender‐specific plausible cutoffs were derived for rEI as a percentage of predicted energy requirement (pER) using Dietary Reference Intake equations for estimated energy requirement (eER) that take into account age, weight, height, and physical activity. We calculated ±1 standard deviation (SD) cutoffs. Because parents were not expected to report meals for children while in childcare, meals between 9am–5pm were excluded. eER was adjusted to reflect this exclusion by assuming 50% of meals were eaten at child care. Using the ±1 SD cutoff, 191 children had plausible rEI. In the total sample, there was over‐reporting of EI for 2‐year‐old children (mean rEI as % pER, 105 ± 39), while under‐reporting was observed for 3–5 year old children (rEI/pER < 100%). The ±1 SD cutoff moved rEI closer to pER in both groups. The methods used in this study offer an approach for overcoming challenges that could help lead to more accurate conclusions of dietary associations.

Grant Funding Source: NHLBI Grant No. R01HL091093
Stress is associated with poor dietary quality in low‐income women
Authors: Arsenault Joanne E , Muth Mary K , Cates Sheryl C , Anater Andrea , Blitstein Jon , Karns Shawn , Wohlgenant Kelly , Council Mary
Published: June 2021

Low‐income women are faced with high risk of stress, poor dietary behaviors, and obesity. The impact of these factors on dietary quality in this population is not well characterized. We conducted a cross‐sectional study among 101 non‐pregnant women with a child enrolled in the Cumberland County (NC) WIC Program. We measured dietary intake by 24‐hr recall; calculated Healthy Eating Index‐2005 (HEI‐2005) scores; administered the perceived stress (PS) scale, and 3‐factor eating behavior questionnaire to assess emotional eating (EE), uncontrolled eating (UE), and cognitive restraint. Sixty‐one percent of the women were obese. The median HEI‐2005 score was 47.8 (interquartile range 40.6 – 60.0). HEI‐2005 did not differ by BMI status. PS was negatively associated with HEI‐2005 (r=−0.26, p=0.01), but EE and UE were not related to HEI‐2005. PS, EE, and UE were negatively associated with the HEI component score of solid fats and added sugars (p<0.01). PS was positively associated with EE (r=0.29, p<0.0001) and UE (r=0.38, p<0.0001). EE was associated with higher BMI (r=0.23, p=0.02). In summary, higher levels of stress were associated with poorer dietary quality and eating behaviors associated with high BMI. Behavioral interventions to reduce stress and modify eating behaviors are warranted in this population.

Funding: RTI International Internal Research and Development Award
Blueberry and blackcurrant consumption increases bone mineral density and content in high fat diet‐induced obese male mice
Authors: Lee Sang Gil , Vance Terrence , Soung Do Yu , Kim Bohkyung , Lee Jiyoung , Koo Sung I. , Drissi M. Hicham , Chun Ock K.
Published: June 2021

We have recently reported that berry polyphenols exert strong antioxidant and anti‐inflammatory effects, which might substantially contribute to the improvement of bone health specifically under obese conditions. Thus, this study was aimed to evaluate the impact of three different berry supplements (blueberry: BB, blackberry: BK, and blackcurrant: BC) on the improvement of bone health using diet‐induced obese C57BL/6J mice. Forty of 12 wk old male mice were assigned into 4 groups and fed 60% high fat diet with/without freeze‐dried berry powders (BB: 5%, BK: 6.3%, and BC: 5.7%) for 12 wks. Plasma insulin‐like growth factor 1 (IGF‐1) levels were measured by ELISA. Bone mineral density (BMD) and bone mineral content (BMC) of femoral proximal and distal epiphysis were measured using DXA. We found that the body weight and IGF‐1 levels were comparable among all experimental groups. However, the BB‐treated group exhibited higher BMD in the proximal and distal epiphysis as well as increased BMC in the distal epiphysis compared to untreated controls (P<0.05). Furthermore, BC‐treated group showed higher BMC in the proximal and distal epiphysis compared to the control (P<0.05). Our findings imply that BB and BC may be effective natural supplements for enhancing bone formation. Further investigations are warranted to delineate the mechanisms underlying these osteogenic effects of BB and BC in vivo.
Identification of Selenoprotein P (Sepp1) binding site on mouse Apolipoprotein E Receptor‐2 (apoER2)
Authors: Kurokawa Suguru , Bellinger Frederick P. , Berry Marla J.
Published: June 2021

Sepp1 transports selenium from the liver to other tissues. ApoER2, a member of the low‐density lipoprotein receptor family, has been demonstrated to facilitate cellular uptake of Sepp1. Sepp1 binding to the extracellular region of apoER2 is believed to initiate endocytosis and supply selenocysteine to cells. The extracellular region of mouse apoER2 consists of four types of protein modules, the ligand binding repeats (LBR), the epidermal growth factor repeat, the YWTD β‐propeller module and the O‐linked sugar module. The LBR has three disulfide bonds and a calcium‐binding site formed by highly conserved acidic amino acid residues. Sepp1 binding was assessed in HEK293T cells overexpressing mouse apoER2‐GFP fusion proteins. Sepp1 was incubated with mouse serum and washed with PBS, and Sepp1 bound to cells was analyzed by SDS/PAGE and western blot analysis. Sepp1 signal appeared in the apoER2 overexpressing cells but not in the control cells incubated with mouse serum. The Sepp1‐binding region within apoER2 was mapped to the five LBR modules. Using further deletion analysis, we have identified which LBRs bind to Sepp1. We are currently investigating the residues involved in Sepp1‐apoER2 binding.

Supported by NIH NIDDK DK047320 and NIMHD G12 MD007601.
Effects of high fat, selenium‐deficient, and high‐selenium diets on diabetes biomarkers in wildtype and glutathione peroxidase‐1 null mice
Authors: Sunde Roger A , Yen Chi‐Liang Eric
Published: June 2021

Supernutritional selenium (Se, 4× RDA) in humans is associated with risk of diabetes. In mice, Se supplementation above the requirement is reported to elevate diabetes biomarkers (DB) and glutathione peroxidase‐1 (Gpx1) overexpression causes obesity and higher DB. We recently reported that high Se in mice increases transcripts associated with increased reactive oxygen (Nrf2) and altered glucose metabolism. Thus high fat, such as in US diets, might modulate impact of Se and Gpx1 on DB. Weanling (4.5 wk old) Gpx1 null (−Gpx1) and wildtype (+Gpx1) mice were fed 0, 0.1, 0.8 or 2.0 μg Se/g as selenite with low (11% cal, LF) or high fat (45% cal, HF) for 12 wk. High Se did not increase body weight whereas HF increased weight 11%. Genotype had no effect on weight in LF mice but HF increased weight in +Gpx1 mice fed 0 μg Se/g. Fasting glucose, glucose tolerance and fasting insulin were decreased by Se, and increased by HF; these effects were blunted in −Gpx1 mice, and only increased by HF in +Gpx1 mice. Unexpectedly, DB in Gpx1 heterozygote (+/−Gpx1) mice fed 0 μg Se/g were indistinguishable from −Gpx1 mice. In summary, HF, Se‐deficient and high‐Se diets had little impact on DB in −Gpx1 mice; HF with high Se had little impact in +Gpx1 mice, but HF in Se‐deficient +Gpx1 mice elevated DB but not in +/−Gpx1 mice. These results suggest that modulation of peroxide tone by diet or genotype can lead to glucose disregulation. (UW Selenium Nutrition Research)