bluuebunny/crossref_metadata_2025_split huggingface dataset:
CRH‐binding protein modulates CRH signaling in a time‐and signaling pathway‐dependent manner
Authors: Evans Ryan T , Seasholtz Audrey F 
Published: June 2021

Corticotropin‐releasing hormone (CRH) and the related urocortins (Ucns) mediate the mammalian neuroendocrine stress response by signaling through two G‐protein‐coupled receptors, CRH‐R1 and CRH‐R2. CRH activity at these receptors is also modulated by a secreted CRH‐binding protein (CRH‐BP), which binds CRH/Ucns with equal or greater affinity than the receptors. Initial studies suggested that CRH‐BP predominantly functions to inhibit CRH‐R1 activation, especially at anterior pituitary corticotropes. However, the role of CRH‐BP in CRH signaling via multiple G‐protein pathways has not been fully examined, especially for CRH‐R2. Using purified CRH‐BP and cell culture systems stably‐expressing CRH‐receptors, we determine the modulatory effect of CRH‐BP on CRH‐R1/2 signaling though adenylyl cyclase and MAPK pathways. These studies demonstrate that the role of CRH‐BP is context sensitive, depending on both the specific signaling pathway and whether CRH encounters CRH‐BP prior or simultaneously to the CRH‐receptors. CRH‐receptor activation is inhibited only when CRH is pre‐incubated with CRH‐BP. Without pre‐incubation, CRH‐BP attenuates signal duration but does not prevent receptor activation.This work was supported by NIH T32 GM07544, T32 HD07048, and U. Michigan Biological Chemistry (RTE), NIH DK42730 (AFS), and MDRTC Cell and Molecular Biology Core.
Establishing heme iron values for the Canadian Nutrient File (CNF)
Authors: Cooper Marcia , Rondeau Isabelle 
Published: June 2021

ObjectivesHeme iron, primarily from the hemoglobin and myoglobin of meat, poultry and fish (MFP) is better absorbed than non‐heme iron. Monsen et al. (1978) assumed that the proportion of heme iron contained in various meats averages 40%, while the remaining 60% is found in the less bioavailable non‐heme form. More recent evidence suggests that this ratio may vary depending on the type and cut of MFP. Currently, the CNF lists only total iron values. The objective of our research was to match heme iron values from the literature to foods within the CNF.MethodsAn extensive literature search was conducted to identify the heme content of different souces of MFP. Values from the literature were then matched to CNF foods with consideration of cuts and similarities to North American cooking methods. In order to match heme values from the literature to MFP foods, average values were often generated across cuts and cooking methods eg. ground chicken was an average of white and dark meat.Results and DiscussionA broad range of heme values were observed across MFP types. The following heme values were attributed: 33–70% for beef cuts, 21–40% for fish, 27–66% for pork cuts, 26–37% for poultry, and 40–63% for veal. When no literature value for heme iron was found eg., game meats, and many types of fish, a value of 40% was used as a default. The heme content of beef, veal and some pork cuts are higher than 40%, while poultry and fish might have lower heme iron contents.ConclusionIncorporating heme iron values into the CNF that are reflective of various MFP provides useful data for assessing iron bioavailability from foods/diets and for developing future nutritional policies targeted at reducing iron deficiency.
Impact of SprinklesTM on reducing childhood vitamin A deficiency in western Kenya
Authors: Ruth Laird J , Grant Frederick , Mandava Usha , Quick Robert , Patel Minal , Mbkaya Charles , Jefferds Maria Elena , Woodruff Bradley , Suchdev Parminder 
Published: June 2021

In 2007–2008, we evaluated community‐based marketing of Sprinkles, a multiple micronutrient powder containing 375μg vitamin A, added to complementary foods.ObjectiveTo measure Sprinkles impact on the prevalence of vitamin A deficiency (VAD) among children 6–35 months.MethodsIn 30 intervention villages, vendors sold Sprinkles to neighbors. In 30 comparison villages, Sprinkles were not promoted. Biweekly household visits measured use. VAD (retinol binding protein <0.70 μmol/L) was measured among 500 children aged 6–35 months before distribution and 12 months later when the children were 18–47 months old.ResultsVAD Prevalence (excluding C‐reactive protein >10 mg/dL)

Intervention n=254 % (95% CI)
Comparison n=24 % (95% CI)
p‐value between groups

Baseline
17.7 (13.0, 22.4)
15.5 (10.9, 20.0)
0.14

12 month follow up
10.2 (6.5, 14.0)
13.0 (8.8, 17.2)
0.08

p‐value within group1
<0.01
<0.01

Change in VAD prevalence (%)
7.5
2.5
<0.012

Paired Chi‐square,
McNemar test

Children in intervention households consumed an average 0.9 sachets/week (~328 μg vitamin A). As Sprinkles use increased, follow up VAD prevalence decreased: no use=17.8%; infrequent use=10.6%; some use=12.0%; and frequent use=3.1% (p = 0.053; adjusted for age, sex, socio‐economic status, and maternal education).ConclusionCommunity‐based marketing of Sprinkles was associated with decreased prevalence of VAD in pre‐school age children.
Predicting epilepsy with peripheral blood transcriptome biomarkers during early latent period
Authors: Karsten Stanislav L. , Vi Nancy , Bragin Anatol , Mazarati Andrei , Kudo Lili C. 
Published: June 2021

Status epilepticus (SE) is a common cause of hippocampal neurodegeneration and synaptic reorganization that may or may not lead to the development of epilepsy. Currently there is no method to predict whether chronic epilepsy would develop in post‐SE patients. We used microarrays to analyze expression changes in the blood of two rat models of chronic epilepsy to identify prognostic peripheral biomarkers of epilepsy.Peripheral blood was collected from Adult Wistar male rats before SE and one, three, seven and thirty days after subjected to SE induced by either systemic pilocarpine or intrahippocampal kainic acid. Blood RNA was used for global transcriptome analysis using microarrays. Post‐SE animals underwent continuous monitoring to retrospectively correlate seizure syndrome with the changes in blood transcriptome profile.We identified nearly 100 predictor/biomarker genes for later occurring chronic seizures regulated similarly in both models, which were confirmed in independent groups of post‐SE rats by semi quantitative RT‐PCR and by a custom designed prognostic microarray.The molecular signature preceding the development of epilepsy present in the peripheral blood allows the design of a prognostic/diagnostic transcriptome biomarker chip for potential epilepsy patients and monitoring the effectiveness of antiepileptogenic therapy.This work was supported by NIH Grant NS060476‐01 (SLK).
Porcine bone marrow‐derived mesenchymal stem cells as cell source for smooth muscle cells in small diameter vascular tissue engineered grafts
Authors: Kolk Felix , Akker Nynke M.S. , van den Molin Daniel G.M. , Post Mark J. 
Published: June 2021

Preconditioning of a synthetic graft with autologous cells is considered the best option to obtain functional vascular grafts. These cells are preferably isolated from an easy accessible patient‐autologous source, such as bone marrow or blood. We investigated if bone marrow‐derived mesenchymal stem cells (MSCs) can be isolated, cultured and instructed to gain a vascular smooth muscle cell (SMC) phenotype.MSCs were isolated from porcine bone marrow by gradient centrifugation and cultured in MSC or SMC‐defined culture media. Cells were analysed for SMC phenotype by determination of mRNA and protein expression of alpha‐SMA, calponin, desmin and collagen.Porcine MSCs can be reproducibly isolated and cultured. No eminent differences in growth dynamics (doubling time, morphology) were observed between animals. Cells grew in multiple layers and showed mesenchymal morphology with an elongated cell shape. Induction of expression of all SMC markers, both at mRNA and protein level, was observed and was highest in cells cultured in MSC‐defined medium.We conclude that porcine MSCs can be reproducibly isolated and differentiated into cells with SMC‐phenotype with sufficient efficacy. We show that the current protocol allows the MSCs to be readily used for application in small diameter vascular grafts.
Tunneling membrane nanotubes generate local calcium signals and may actively propagate calcium signals between cells
Authors: Smith Ian F , Shuai Jianwei , Parker Ian 
Published: June 2021

Cells have long been known to employ gap junctions and synapses to communicate with their neighbors. A new mechanism has recently been proposed following the discovery of tunneling membrane nanotubes (TNTs) between cells [1]. TNTs are dynamic membrane protrusions with lengths up to several tens of microns and diameters of 50–800nm, which permit the exchange of membrane components and cytoplasmic molecules between neighboring cells. Ca2+ diffusion along TNTs has been proposed as a means of intercellular communication [2], yet our modeling simulations show that passive diffusion alone is insufficient to account for efficient transmission of Ca2+ between cells. Instead, we observe local spontaneous and inositol trisphosphate (IP3)‐evoked mediated Ca2+ signals within the length of TNTs formed between cultured SHSY‐5Y neuroblastoma cells. Moreover, immunostaining demonstrates the presence of both ER and IP3 receptors along the TNT. We propose that IP3Rs are involved in actively propagating intercellular Ca2+ signals along TNTs, acting as amplification sites to overcome limitations of passive diffusion in a chemical analog of electrical transmission of action potentials along axons.Supported by grants NIH GM 40871 and GM65830.
Do vertebrate rhodopsins contain an allosteric binding site(s) for retinoids?
Authors: Isayama Tomoki , Miyazono Sadaharu , Okada Tetsuji , Kono Masahiro , Crouch Rosalie , Zimmerman Anita , Makino Clint 
Published: June 2021

We found by microspectrophotometry that β‐ionone partitioned into the outer segment membranes of salamander green‐sensitive (GS) and blue‐sensitive (BS) rods with greater uptake into BS rods. Electrophysiology showed that BS rod rhodopsin, but not that of GS rods, was activated and bleached by β‐ionone. But biochemical assays using rhodopsins formed from recombinant salamander GS rod and BS rod opsins and 11‐cis retinal (A1) showed little activation by β‐ionone. Since salamander photoreceptors normally contain both A1 and 3‐dehydro 11‐cis retinal (A2)‐based visual pigments, we hypothesized that only the latter activated pharmacologically. We recorded BS rods whose native chromophore had been partially replaced by A1. Lowering the amount of A2 rhodopsin decreased pharmacological activation. Because β‐ionone does not occur naturally in the retina, we also examined the effects of vitamin A on rod activity. In contrast to β‐ionone, vitamin A activated rhodopsin in both GS and BS rods, and also sensitized rods to UV light, presumably by resonance energy transfer. Thus the different effects of retinoids on rods argue for the existence of allosteric binding sites on rhodopsins.Research Support: NEI EY011358 and Lions of Massachusetts
Activation of Neutral Sphingomyelinase‐2 and Protein Phosphatase 2A by Interleukin‐1B: role in IRAK‐1 degradation and intracellular translocation
Authors: Dobierzewska Aneta , Giltiay Natalia , Rutkute Kristina , Karakashian Alexander , Nikolova‐Karakashian Mariana 
Published: June 2021

The objective of this study is to understand the role of Neutral sphingomyelinase‐2 (NSMase‐2) in hepatic response to Interleukin 1β (IL‐1β). The IL‐1β signaling cascade is initiated by rapid phosphorylation of IL‐1β receptor activated kinase‐1 (IRAK‐1) in response to ligand binding. Subsequently, the phoshporylated IRAK‐1 is ubiquitinated and degraded and the rate of its degradation is known to affect the magnitude of IL‐1β response. We show that the activity of protein phosphatase 2A (PP2A) gradually increases in response to IL‐1β stimulation with a maximum effect seen 30 minutes after the stimulation. The PP2A catalytic subunit directly interacts with IRAK‐1, indicating that IRAK‐1 is a novel PP2A substrate. Furthermore, treatment of primary rat hepatocytes or HEK293cells overexpressing the IL‐1β receptor with PP2A inhibitor, okadaic acid, enhances the rate of IL‐1β‐induced IRAK‐1 ubiquitination and degradation.NSMase‐2 mediates the activation of PP2A by IL‐1β. Overexpression of NSMase‐2 enhances PP2A activity and delays IRAK‐1 degradation. In contrast, NSMase‐2 silencing or inhibition by pharmacological inhibitor causes faster IRAK‐1 degradation. NSMase‐2 also plays a role in IRAK‐1 intracellular translocation in response to IL‐1β. These experiment identify NSMase 2‐and PP2A as novel physiological regulators of IRAK‐1 phosphorylation.Supported by NIA RO1 AG026711.
A genetic approach to optically investigate P2X2 receptor activation in vivo using an activity‐dependent FRET based reporter tag
Authors: Kracun Sebastian , Khakh Baljit S. 
Published: June 2021

P2X receptors are ATP‐gated cation selective ion‐channels found throughout the body, including the CNS where ATP signaling is proposed to contribute to normal brain physiology, whereas aberrant P2X receptor expression may result in phenotypes relating to nervous system dysfunction, including epilepsy. However, a precise mechanistic understanding of P2X receptors in the brain does not exist and their role in epileptiform activity remains unclear. Our goal was to generate transgenic P2X2 reporter mice and, thus investigate in vivo P2X2 receptor mediated ATP signaling and its involvement in the hyperexcitability of neural networks. We have developed a non‐invasive approach to optically track the location and activation of P2X2 receptors, using a calcium sensitive FRET based reporter, with sensitivity equal to whole‐cell patch clamp recording (P2X2‐YC; Nature Methods, 2008). Here, we describe the generation of lentiviruses expressing P2X2‐YC and the DNA construct design and bacterial artificial chromosome (BAC) based transgenic method to generate mice expressing P2X2‐YC under the influence of the CaMKIIα gene promoter. We have successfully generated six ‘founder’ mouse lines verified by genomic PCR and have tested lentiviruses in vitro. The mice and viruses will be further characterised using immunohistochemistry, fluorescence imaging and electrophysiology to assess P2X2‐YC gene expression.This research was supported by the NIH.
The molecular mechanism of the Hsp70‐lipid interaction (1002.6)
Authors: McCallister Chelsea , Nikolaidis Nikolas 
Published: June 2021

Hsp70s are molecular chaperones essential for cellular homeostasis and survival. Several Hsp70s associate with cellular membranes, where they bind to specific lipids. The association of Hsp70s with lipids anchors them to the plasma membrane, where they serve several functions, stabilizes the lysosomal membrane, and is required for microautophagy. Despite these essential functions the Hsp70‐lipid interactions remain largely uncharacterized. To understand the molecular mechanism of these interactions we characterized the binding of HSPA1A, a cytosolic Hsp70, to lipids. We determined the binding affinities of recombinant HSPA1A to several negatively charged phospholipids and established that allosteric communication between the nucleotide‐binding and substrate‐binding protein domains is important for lipid‐binding. We also determined that a conformational change caused by nucleotide‐binding reduces lipid‐binding for a particular subset of lipids, while binding of protein substrates has no effect on the lipid‐binding. Additionally, we determined that the HSPA1A‐lipid interaction is not purely electrostatic, but it also depends on other forces. Furthermore, we found that HSPA1A embeds in membranes only when bound to specific lipids and that membrane embedding is independent of the affinity of the interaction. Finally, we observed that while lipid‐binding does not affect the ability of HSPA1A to hydrolyze ATP, it minimizes the refolding activity of the protein suggesting that lipid‐binding could represent a new regulatory mechanism of chaperone function.Grant Funding Source: Supported by funds from CSUPERB and CSUF to NN, and HHMI to CM and NN
Insulin‐stimulated neuronal nitric oxide synthase phosphorylation is AKT2‐dependent in C2C12 skeletal muscle cells (1013.13)
Authors: Hinchee‐Rodriguez Kathryn , Adamo Martin , Masters Bettie Sue , Roman Linda 
Published: June 2021

Type 2 Diabetes (T2DM) is a major cause of death in the United States, and has become a global pandemic. T2DM results from reduced insulin sensitivity coupled with a relative failure of insulin secretion. Reduced insulin sensitivity is associated with reduced nitric oxide synthase (NOS) activity and impaired glucose uptake in T2DM skeletal muscle. Upon insulin stimulation, nitric oxide synthesis increases in normal adult skeletal muscle, whereas no such increase is observed in T2DM adults, which is significant given that nitric oxide stimulates glucose uptake in skeletal muscle. We have shown that neuronal NOS (nNOS) is phosphorylated at Ser1450, resulting in its activation, in response to insulin in skeletal muscle, but it remains unknown which kinase(s) in the insulin signaling cascade is responsible. Immunoblot analyses indicate that in C2C12 myotubes, insulin‐stimulated nNOS phosphorylation is dependent on one or more AKT isoforms, as AKTi, which prevents AKT1/2 activation, inhibited nNOS phosphorylation. Moreover, the AKT2‐specific inhibitor, AKT2i, also attenuated nNOS phosphorylation, implicating this isoform specifically. These results are consistent with the essential role of AKT2 in mediating glucose uptake in skeletal muscle and show, for the first time, that C2C12 myotube nNOS phosphorylation, and its associated increase in activity, are dependent on insulin signaling‐activated AKT2.Grant Funding Source: Supported by NIH Grant No. GM052419 to BSM/LJR
Pregnancy in Mbale, Uganda: perceptions of food security and influences on women's breastfeeding intentions (1014.7)
Authors: Ickes Scott , Pugh Laura 
Published: June 2021

Pregnancy is a nutritionally vulnerable time for both the mother and the child; nutritional demands increase, as do the consequences for failing to meet these needs. Traditional beliefs, social support, psychological health, food security, other responsibilities, income, and autonomy in decisions all play roles in what women eat during pregnancy. The purpose of this study was to understand women’s perceptions of food security during pregnancy, and to assess the concordance of desired versus actual dietary changes during pregnancy among low‐income pregnant women in Mbale, District, Uganda. We conducted semi‐structured, in‐depth interviews (n=15) and one focus group (n=8) among pregnant women living in slum and rural settings. The majority of women report eating less during pregnancy. Often they describe eating fewer meals in a day, in addition to cutting out staple foods due to nausea. All women changed their eating habits during pregnancy, both cutting out foods that made them feel sick and introducing foods they considered to be necessary or healthier. Only two women felt they were in control of what and how much they ate; all others said that resource constraints prevent eating how much and what kinds of food they’d prefer. Half of the woman also worried that their household did not always get enough total food. Few women receive support for either food or responsibilities during their pregnancies. When asked, most women intended to exclusively breastfeed, but frequently misconstrued the definition of exclusive. Pregnancy should be a renewed focus among nutrition programs in Uganda, to dispel misconceptions around correct eating habits and help women form strong and achievable breastfeeding intentions. It is vital that even food insecure women gain access to adequate calories and nutrients in order to prevent low birth weight and stunted babies, and to give them enough energy reserves to feel confident in sufficient high quality breast milk.Grant Funding Source: Supported by a College of William and Mary Monroe Scholarship
Association between dairy intake and brain glutathione levels in older adults (1018.4)
Authors: Choi In‐Young , Lee Phil , Denney Douglas , Spaeth Kendra , Nash Olivia , Roth Alexandra , Lierman Jo , Sullivan Debra 
Published: June 2021

Glutathione (GSH) plays a key role in protecting cells against oxidative stress. A reduction in GSH levels is noted in brain tissue undergoing oxidative stress in health and disease. We investigated the effect of dietary factors, specifically dairy intake, on oxidative stress, using a unique, noninvasive measure of brain GSH levels in older adults. Healthy subjects (n=57; 68 ± 6.1 yrs; BMI = 25 ± 4) whose daily dairy consumption was low (n=20; < 1 serving/day), moderate (n=22; >1,<3) or at recommended levels (15, >3) were recruited. Brain GSH was measured using a specially designed 1H MRSI technique for GSH at 3 T. Dietary intake was assessed with 7‐day food records, entered into NDS‐R. Total dairy servings were correlated with GSH levels in the frontal (Spearman Rs = .37, p = .004) and parietal regions (Rs = .46, p < .001). Correlations were also found between frontal GSH and milk (Rs = .36, p =.006) and between parietal GSH and milk (Rs = .38, p = .004), cheese (Rs = .40, p = .002) and calcium (Rs = .31, p = .022), but were lower than those for total dairy servings. The dairy intake groups did not differ in age, BMI, or fat consumption. Recommended dairy consumers had higher energy, carbohydrate, and protein intake, but these differences did not account for the relationship between dairy servings and GSH. The results suggest that increased dairy intake may be beneficial to brain health in aging via increasing cerebral antioxidant capacity.Grant Funding Source: Supported by Dairy Research Institute
Mineral content and in vitro iron bioavailability in seaweeds (1042.7)
Authors: Dunn Michael , Flores Shireen , Dobbs Joannie 
Published: June 2021

Iron (Fe) deficiency remains a public health problem despite large‐scale intervention programs. Deficiency is often due to low iron intake and/or bioavailability, especially in plant‐based diets. With the Dietary Guidelines recommending a shift toward plant‐based diets, there is increased need to identify plant foods that are good sources of iron. Seaweeds are known to be rich in iron, but its bioavailability is poorly understood. Our objective was to evaluate the quality of seaweeds as an iron source by comparing their iron content and bioavailability to spinach. Seaweeds were obtained from commercial sources. Mineral assay by ICP‐ES showed that 10 of 13 seaweeds analyzed contained more Fe/g dry matter (DM) than spinach. Iron content in the seaweeds ranged from 73 to 3490 ug/g DM compared to 166 ug/g DM in spinach. Because of the high Fe content, most seaweeds could be considered good sources of iron based on a 10 g DM serving, e.g. 100% of the Daily Value of iron could be obtained from just 5.2 g of dulse powder, 2.3 g of dried sea lettuce, or 6 g of dried nori (one sheet). However, despite their high Fe content, bioavailability studies using the in vitro digestion/Caco‐2 cell model indicated that many seaweeds do not provide more bioavailable Fe per g DM than spinach. This was due to low Fe absorption efficiencies in the seaweeds. Exceptions were nori and sea lettuce which provided 3 and 5‐fold more bioavailable Fe per g DM than spinach, respectively. The higher bioavailability resulted from a combination of higher absorption efficiencies and higher Fe contents than spinach. In addition, vitamin C increased Fe bioavailability in these two seaweeds by over 100%. Some seaweed samples were found to contain high levels of aluminum (2 mg/g DM), arsenic (66 ug/g DM), or manganese (500 ug/g DM). The level of these contaminants should be considered when recommending seaweeds for regular consumption. We conclude that certain seaweeds could be good sources of iron provided that levels of potentially toxic minerals are low.Grant Funding Source: Supported by USDA/Hatch HAW000279‐H