bluuebunny/crossref_metadata_2025 huggingface dataset:
Carbon Monoxide Induces Dose‐Dependent Relaxation of Airway Smooth Muscle via cGMP Signaling Pathway
Authors: Jakupaj Muharrem , Lajçi Azem , Bexheti Sadi , Temaj Gazmend , Cenaj Asllan , Sopi Ramadan B
Published: June 2021

In present study we investigated the effect of endogenous carbon monoxide (CO) on relaxation of rat airway smooth muscle (ASM). Airway segments were excised from 28 day‐old rats. In pre‐constricted tracheal smooth muscle (TSM), electrical field stimulation (EFS) was applied to induce relaxation in absence or presence of heme oxigenase (HO) substrate ‐ hematin (10 μM and 100 μM); HO inhibitor tin protoporphyrin‐IX (SnPP‐IX; 100 μM); nitric oxide (NO) synthase (NOS) inhibitor Nω‐nitro‐L‐arginine methyl ester (L‐NAME; 100 μM); soluble guanylyl cyclase inhibitor 1H‐[1,2,4]oxadiazolo[4,3‐a]quinoxalin‐1‐one (ODQ; 10 μM) and the SnPP‐IX + L‐NAME. All experiments were performed in presence of isoproterenol (100 μM) and indomethacin. Hematin increased relaxant responses of ASM in a dose‐dependent manner. SnPP‐IX and L‐NAME, alone or combined significantly reduced relaxant responses induced by EFS in control and hematin‐preincubated tissues. ODQ also reduced relaxant responses to the level obtained by combining SnPP‐IX and L‐NAME.

According to the results we conclude that in rat TSM, CO induces dose‐dependent relaxation and nondrenergic noncholinergic (NANC) inhibitory responses use CO and NO as main molecules to induce relaxation via cGMP signaling pathway.
Diaphragm Activation via High Frequency Spinal Cord Stimulation (HF‐SCS) in a Rodent Model of Spinal Cord Injury
Authors: Kowalski Krzysztof E , Hsieh Yee‐Hsee , Dick Thomas E , DiMarco Anthony F
Published: June 2021

Objective

HF‐SCS is a novel technique of inspiratory muscle activation involving activation of spinal cord pathways. All previous studies of this method were performed in a dog model of spinal cord injury. Since the rodent respiratory system is also a relevant model for study of neuronal circuitry function and this species is more accessible, we sought to a) evaluate the effects of HF‐SCS and b) determine the methodology of application of this technique in rats.

Methods

In 9 rats, diaphragm multiunit and single motor unit EMG activity was assessed during spontaneous breathing and HF‐SCS applied on the ventral epidural surface of the spinal cord at the T2 level following C1 spinal section.

Results

Mean maximum firing frequencies of the diaphragm during spontaneous breathing and HF‐SCS were 23.3 ± 1.4 Hz (range: 9.8 – 51.6 Hz) and 26.6 ± 1.3 Hz; range: 12.0 – 72.9 Hz, respectively, at comparable inspired volumes. Moreover, HF‐SCS was successful in pacing these animals over a 60‐min period without evidence of system fatigue.

Conclusion

Our results suggest that, similar to the dog model, HF‐SCS in rodents results in activation of spinal cord tracts which synapse with the phrenic motoneuron pools, allowing processing of the stimulus and consequent physiologic activation of the inspiratory muscles. The rat may be a useful model for further studies evaluating phrenic motoneuron physiology.
A new pathway to STEM ‐ the marble game
Authors: Nelson Peter Hugo
Published: June 2021

Recently there have been multiple calls for curricular reforms to develop new pathways to the science, technology, engineering and math (STEM) disciplines. The Marble Game answers these calls by providing a conceptual framework for quantitative scientific modeling skills useful across all the STEM disciplines. The approach actively engages students in a process of directed scientific discovery. In a “Student Assessment of their Learning Gains” (SALG) survey, students identified this approach as producing “great gains” in their understanding of real world problems and scientific research. Using the marble game, students build a conceptual framework that applies directly to random molecular‐level processes in biology such as diffusion and interfacial transport. It is also isomorphic with a reversible first‐order chemical reaction providing conceptual preparation for chemical kinetics. The computational and mathematical framework can also be applied to investigate the predictions of quantitative physics models ranging from Newtonian mechanics through RLC circuits. To test this approach, students were asked to derive a novel theory of osmosis. The test results confirm that they were able to successfully apply the conceptual framework to a new situation under final exam conditions. The marble game thus provides a pathway to the STEM disciplines that includes quantitative biology concepts in the undergraduate curriculum ‐ from the very first class.

Student modules (and instructor guides) are available for testing and evaluation at http://circle4.com/biophysics. Support from the NSF (Grant DUE‐0836833) is gratefully acknowledged.
Complement Factors C3a and C5a Contribute to Angiogenic Imbalance in Preeclampsia
Authors: Midttveit Erica , Needham Karen , Banek Christopher T , Rear Alice A , Regal Jean F , Gilbert Jeffrey S
Published: June 2021

Although recent evidence from our lab and others suggests increases in circulating concentrations of complement activation products C3a and C5a play a key role in pathogenesis of preeclampsia, the exact role they play in disease progression remains unclear. We hypothesized complement factors C3a and C5a would stimulate production of anti‐angiogenic factors (sEng) and decrease production of pro‐angiogenic factors (PlGF) from placental and endothelial cells. BeWo trophoblast cells and endothelial cells (HUVECs) were cultured in complete cell media for 2 hr with 10 and 100 nM C3a or C5a in culture media at three oxygen concentrations (20%, 8%, and 1.5%). sEng and PlGF were measured in culture media by ELISA. Treatment of HUVECS with C3a and C5a significantly decreased sEng production (p < 0.05). C3a increased PlGF (p < 0.05), while C5a decreased PlGF (p < 0.05). BeWo cells treated with 100 nM C5a increased sEng production (p < 0.05). Angiogenesis was measured by determining endothelial cell tube formation in HUVECs exposed to C3a or C5a for 8 hr. C5a at 100 nM completely prevented tube formation (p < 0.01). The present data indicate C3a and C5a may have opposing actions in placental and endothelial cells. In addition, C5a may be the key product of complement system activation responsible for production of circulating anti‐angiogenic factors.
Renal Infiltration of T Lymphocytes in a Rat Model of Polycystic Ovary Syndrome
Authors: Moulana Mohadetheh , Wallace Kedra , Hosick Karen , Lamarca Birdie , Reckelhoff Jane
Published: June 2021

Polycystic ovary syndrome (PCOS) is the most common hormonal disorder among women of reproductive age. PCOS is strongly linked to increased risk of cardiovascular diseases (CVD). The mechanisms responsible for PCOS hypertension are not clear. We have characterized a rat model of PCOS, the hyperandrogenemic rat (HAF), that exhibits many of the characteristics of PCOS in women. This study aimed to test the hypothesis that PCOS rats exhibit increased T cells in kidney that could potentially play a role in hypertension. Dihydrotestosterone (DHT) (7.5 mg/90 days) or placebo, pellets were implanted subcutaneously in female SD rats (n = 4–5/group) at 4weeks of age and compared to placebo. After 6 weeks of DHT treatment, kidneys were collected and infiltrated CD4+, CD8+, Th17, and CD4+CD28null T cells were measured by flow cytometry. The number of renal infiltrated CD4+ T cells was increased in HAF rats (Placebo: 10 ±1 vs. HAF: 22 ±1 % gated p <0.05). The number of infiltrated Th17 (Placebo: 19 ±1 vs. HAF: 23 ±1 % gated p <0.05) and CD4+CD28nullT cells (Placebo: 6 ±1 vs. HAF: 15 ±2 % gated p <0.05) were significantly increased in HAF rats compared to Placebo. These data show that infiltrated T cells, in particular Th17 and CD4+CD28null subpopulations are increased in the kidney of HAF rats, a model of PCOS. Results from this study suggest a potential role for infiltrated T cells as a link between hypertension and CVD in PCOS patients.
A study of plasma corticosterone levels in an intrauterine growth restricted rat model at prenatal E19 and postnatal P14
Authors: Porter Nicholas K. , Williamson Danielle T. , McMillan Tiarra , Arguello Irene , Ojeda Norma B. , Intapad Suttira , Alexander Barbara T. , Hennington Bettye Sue
Published: June 2021

A role of fetal exposure to maternal steroids is suggested as a potential mechanism that contributes to the developmental programming of adult CV risk. We hypothesize that the placenta of the IUGR fetus has a higher levels of corticosterone leading to a reduction in placental size and that transmission of maternal steroids to the fetus may serve as a potential mediator of later programmed CV risk. At day 14 gestation RUPP was performed on pregnant rat dams with sham surgeries performed on Control pregnant rat dams. Fetuses were sacrificed at E19 and E20 and P14. Sampling indicated a significant decrease in fetal weight and PW at E19 in the IUGR compared to the Control fetus; PW was significantly decreased at E20 in IUGR compared to Control. However, placental efficiency was significantly higher in IUGR relative to Control at E19 and E20. BW was significantly decreased in IUGR pups compared to Control. A significant increase in plasma levels of corticosterone were observed at E19 in RUPP compared to E19 Control dams; circulating corticosterone levels were also significantly increased in P14 RUPP dams. However, fetal plasma corticosterone levels were not altered in IUGR at E19 compared to Control. In conclusion, early measurements indicated that IUGR fetal weight and weight at birth were significantly reduced by placental insufficiency; however, placental efficiency was increased perhaps indicative of a compensatory mechanism.
Mechanism of gene regulation employed by the bHLH transcription factor TWIST2: Repression of the CHRDL1 gene
Authors: Casasnovas Jose , Franco Hector , Cadilla Carmen
Published: June 2021

Puerto Rican Setleis Syndrome (SS) patients harbor a nonsense mutation in TWIST2 (Q119X) which truncates the C‐terminus. We found that chordin‐like 1 (CHRDL1) is up‐regulated in SS patients skin fibroblasts and silencing of TWIST2 caused an increase in CHRDL1 expression. CHRDL1 codes for a BMP antagonist expressed in mesenchymal tissues. Putative TWIST binding sites were found upstream from the transcription start site of CHRDL1. EMSA analysis showed specific binding of Twist1 and TWIST2 homodimers, as well as E12/Twist heterodimers, to the −2421 site. Q1191X was only able to bind to the −2421 site as a heterodimer with E12. An adjoining E‐box was bound by SREBP1c/ADD1, a bHLH protein known to be repressed by TWIST2. EMSA analysis suggest that TWIST2 and ADD1 could compete for binding. Luciferase reporter assay revealed that the CHRDL1 upstream region drives its expression and ADD1 increased it 2.6X over basal levels. TWIST2, but not Q119X, blocked activation by ADD1. Overexpression of Q119X increased the expression of the reporter gene. The dysregulation of CHRDL1 in SS patients could be due to the lack of binding of Q119X as a homodimer and thus not competing with ADD1. The binding of Q119X‐E12 heterodimer could increase the expression of CHRDL1. In addition, Q119X could be sequestering other transcription factors important for CHRDL1 repression. Supported by NIH Grants G12RR03051, G12MD007600 and R25GM061838.
Cholesterol homeostasis in mouse bone marrow‐derived macrophages from RA‐ and SLE‐like murine models: a possible mechanism for atherogenesis (1001.1)
Authors: Voloshyna Iryna , Littlefield Michael , Teboul Isaac , Archer Amy , Palaia Thomas , Ragolia Louis , Perlman Harris , Reiss Allison
Published: June 2021

Objective: Atherosclerosis contributes to 30% of deaths in systemic lupus erythematosus (SLE) and cardiovascular mortality is 50% higher in rheumatoid arthritis (RA) than in the general population. Little is known about mechanisms leading to progression of atherosclerosis at the cellular level. Here we analyze expression of key cholesterol transport proteins that impact atheroma development in BMDM from KRNAg7 (RA) and apoE‐/‐Fas‐/‐ (SLE) mice as disease evolves.

Methods: Male homozygous C57BL/6J, apoE‐/‐ , apoE‐/‐Fas‐/‐ , KRN and KRNAg7 mice (n=5 per group) were studied. Femurs were dissected and cell suspensions obtained by flushing bones. BMDM were generated by culturing cells for 7 days with MCSF. Expression of efflux proteins ATP binding cassette transporters (ABC)A1 and ABCG1, and scavenger receptors CD36 and LOX1 were evaluated by QRT‐PCR.

Results: 6 wk mice had no significant changes in cholesterol efflux proteins. 30 wk apoE‐/‐, apoE‐/‐Fas‐/‐ mice display 2‐fold reduction in ABCA1 and ABCG1 mRNA (n=3, P<0.01). 6 wk KRNAg7 mice show increased CD36 (225.5±54% vs. wt mice at 100%) (n=3, P<0.01). LOX‐1 did not differ significantly from C57BL/6J and KRN mice. ApoE‐/‐Fas‐/‐ mice had increase in CD36 mRNA (150±23% at 6 wk; 161.3±12.3% at 30 wk, n=3, P<0.05) LOX1 expression was unchanged. In contrast, apoE‐/‐ mice display a 2‐fold increase in both CD36 and LOX1 at 6 wk and up to a 5‐fold increase at 30 wk.

Conclusions: This study provides insight into molecular alterations that contribute to atherogenesis in SLE and RA. We demonstrate that imbalance between cholesterol efflux and influx contributes to atherosclerosis progression. Further metabolic screening may identify optimal time‐points for intervention.
Apolipoproteins C‐I and C‐III inhibit lipoprotein lipase activity by displacement of the enzyme from lipid droplets (1002.4)
Authors: Larsson Mikael , Vorrsjo Evelina , Talmud Philippa , Lookene Aivar , Olivecrona Gunilla
Published: June 2021

Apolipoproteins (apo) C‐I and C‐III are known to inhibit lipoprotein lipase (LPL) activity but the molecular mechanisms for this remain obscure. We present evidence that either apoC‐I or apoC‐III, when bound to triglyceride‐rich lipoproteins, prevent binding of LPL to the lipid/water interface. This results in decreased lipolytic activity of the enzyme. Site‐directed mutagenesis revealed that hydrophobic amino acid residues centrally located in the apoC‐III molecule are critical for attachment to lipid emulsion particles and consequently inhibition of LPL activity. Triglyceride‐rich lipoproteins stabilize LPL and protect the enzyme from inactivating factors such as angiopoietin‐like protein 4 (angptl4). Addition of either apoC‐I or apoC‐III to triglyceride‐rich particles severely diminished their protective effect on LPL and rendered the enzyme more susceptible to inactivation by angptl4. These observations were seen using chylomicrons as well as the synthetic lipid emulsion Intralipid. In the presence of the LPL activator protein apoC‐II more of apoC‐I or apoC‐III was needed for displacement of LPL from the lipid/water interface. In conclusion, we show that apoC‐I and apoC‐III inhibit lipolysis by displacing LPL from lipid emulsion particles. We propose a role for these apolipoproteins also in the irreversible inactivation of LPL by factors such as angptl4.

Grant Funding Source: Supported by Swedish Science Council Grant 12203
Protein self‐association of N‐terminal domain of β‐1,3‐glucan recognition protein upon binding to β‐1,3‐glucan stimulates the prophenoloxidase activation in Manduca sexta (1007.4)
Authors: Takahashi Daisuke , Dai Huaien , Hiromasa Yasuaki , Krishnamoorthi Ramaswamy , Kanost Michael
Published: June 2021

Insect β‐glucan recognition protein (βGRP), a pathogen recognition receptor for innate immune responses, detects β‐1,3‐glucan on fungal surfaces via its N‐terminal carbohydrate binding domain (N‐βGRP) and triggers serine protease cascades leading to the activation of prophenoloxidase (proPO) or Toll pathway. Here we use biochemical and biophysical techniques to probe the molecular interaction of N‐βGRP from Manduca sexta with laminarin, soluble β‐1,3‐glucan. Intriguingly, the carbohydrate binding induces the formation of two types of protein self‐association of N‐βGRPs depending on the molar ratio of carbohydrate to protein (C/P). Insoluble aggregation occurs at the lower molar ratio (C/P ~1), and a soluble oligomer, likely containing at least six N‐βGRP molecules, forms at the higher molar ratio (C/P >5). Further, the PO activation is significantly enhanced in the naïve plasma supplemented with the insoluble aggregate of N‐βGRP. The soluble complex formed in plasma with laminarin also stimulates the PO activation, but at a lower level. Our results indicate that the self‐association of βGRPs on binding to β‐1,3‐glucan is an essential step to stimulate the immune responses against fungal infection. We also discuss the possible involvement of other hemolymph proteins in the self‐association complex of βGRP for downstream signaling.

Grant Funding Source: Supported by NIH grant GM‐41247
Binge alcohol promotes acute liver injury through a CYP2E1‐HIF‐1α‐dependent apoptosis pathway in mice and humans (1010.1)
Authors: Yun Jun‐Won , Son Min‐Jeong , Abdelmegeed Mohamed , Banerjee Atrayee , Morgan Timothy , Yoo Seong‐Ho , Song Byoung‐Joon
Published: June 2021

Binge drinking, a common pattern of alcohol intake, has been known to amplify liver injury caused by chronic alcohol abuse. This study was aimed to investigate if and how binge alcohol activates hepatic hypoxia‐inducible factor 1α (HIF‐1α) and its downstream target associated with apoptosis and protein nitration. We analyzed mice treated with three ethanol doses and autopsied human specimens selected as binge or non‐binge group. We observed positive correlations among blood alcohol concentration (BAC), cytochrome P450 2E1 (CYP2E1) and HIF‐1α in mice and humans exposed to binge alcohol. The expressed levels and activities of CYP2E1 showed significantly higher correlation with BACs in humans. HIF‐1α levels were also positively correlated with BACs or CYP2E1 activities in humans. Consistently with HIF‐1α activation, binge alcohol also promoted hepatocyte apoptosis and hepatic protein nitration. Particularly, significant correlations of hepatic iNOS and 3‐nitrotyrosine formation were found with BACs, CYP2E1 and HIF‐1α in humans. The HIF‐1α activation and its apoptosis‐ or protein nitration‐related downstream targets were significantly alleviated in binge alcohol‐exposed Cyp2e1‐null mice, suggesting the role of CYP2E1 in HIF‐1α‐associated apoptosis and protein nitration. Binge alcohol promotes acute liver injury in mice and humans through a CYP2E1‐HIF‐1α‐dependent apoptosis pathway.
IL‐8 inhibits bortezomib‐induced apoptosis in ovarian cancer cells (1010.2)
Authors: Phyo Sai , Singha Bipradeb , Gatla Himavanth , Vancurova Ivana
Published: June 2021

Proteasome inhibition is a promising therapeutic strategy in a number of human cancers, including ovarian cancer, one of the most lethal human cancers. Bortezomib (BZ) is the first FDA approved proteasome inhibitor that has a remarkable anti‐tumor activity in many hematological malignancies. In solid tumors, BZ has been less effective; however, the underlying mechanisms are not fully understood. The rationale behind BZ development and use was its inhibition of NFκB activity and resulting suppression of NFκB‐dependent pro‐inflammatory and anti‐apoptotic genes. However, recent studies from our laboratory demonstrated that while BZ decreases expressions of most NFκB‐regulated genes, it actually increases expression of the pro‐inflammatory and pro‐angiogenic chemokine, IL‐8, in ovarian cancer cells. The goal of this study was to investigate whether the BZ‐increased IL‐8 expression regulates survival of ovarian cancer cells. Here, we show that suppression of IL‐8 levels by siRNA significantly induces apoptosis in BZ‐treated ovarian cancer SKOV3 cells. Our results indicate that the BZ‐increased IL‐8 expression represents one of the mechanisms responsible for the decreased BZ effectiveness in ovarian cancer, and suggest that a new combination therapy targeting the IL‐8 expression might enhance BZ effectiveness in ovarian cancer treatment.

Grant Funding Source: Supported by NIH grants AI085497 and CA173452 to I.V.
Cellular effect of insulin on proliferation of monocytes (1011.4)
Authors: Naderi Jamal , Feuerherm Astrid , Nguyen Thanh , Johansen Berit
Published: June 2021

Diet macronutrient composition affects insulin action(1). Insulin is essential for metabolic homeostasis in mammals(2). THP‐1 is a human myeloid leukemia cell line(3) which is a suitable model‐system for mimicking human monocytes and macrophages in metabolic inflammation, diabetes and vasculature‐related research(4‐6) . In this study, we used THP‐1 cells to investigate if insulin affect proliferation. Actively proliferating THP‐1 cells were serum starved prior to treatment with varying doses of insulin (20nM, 100nM and 1 µM) with a D‐glucose content of 11 mM or 22 mM for 24 hours (hrs) to 144 hrs. We found that the response was most evident at 24 hrs at 100 nM insulin (p<0.05). There was no stimulating effect of adding D‐glucose on proliferation. Based on the different insulin stimulation times (24, 48, 72, 96, 120 and 144 hrs), we found that insulin‐stimulated proliferation was most prominent following 24 hrs of exposure. This stimulatory effect on proliferation was reduced following longer exposure periods. Interestingly, we also observed that insulin affected morphology of monocytes and adherence. In conclusion, insulin may have proinflammatory effects by affecting several aspects of monocyte function, including proliferation and adherence; important factors for immune and vascular function.
Does newt blood regenerate via circulating stem cells? (1011.6)
Authors: Mele Grace , Sessions Stanley
Published: June 2021

The purpose of this study is to investigate how salamander blood regenerates. We initially noticed that there seem to be dividing cells in the circulating blood of salamanders that have been bled via heart injury. We hypothesized that blood, including red blood cells, regenerates from stem cells in the circulating blood. If this hypothesis is true, then if we bleed a newt and treat it with colchicine, we should be able to prepare mitotic chromosomes from circulating blood. We bled the newts by injuring their hearts via microsurgery. Colchicine was used to arrest cells in mitotic metaphase by inhibiting microtubule polymerization. Positive results support the idea that circulating blood of salamanders contains stem cells that can be recruited for regeneration. It could also lead to an improved and eventually non‐destructive new method to study salamander cytogenetics.
Antagonism of the prostaglandin E2 EP1 receptor in MDCK cells increases growth through activation of Akt and the epidermal growth factor receptor (1012.6)
Authors: Taub Mary , Mathivanan Paremala , Parker Robert , Rudra Trina , Ariff Mohamad
Published: June 2021

Prostaglandin E2 (PGE2) plays a number of roles in the kidney that are mediated by 4 classes of E‐prostanoid (EP) receptors, including EP2 and EP4, which activate adenylate cyclase (AC), EP3 that inhibits AC, and EP1, that activates Phospholipase C. Each of these receptors contributes to a number of renal diseases. Here, the role of EP1, EP2 and EP4 in mediating the effects of PGE2 on MDCK cell growth is examined. The results indicate that EP2 and EP4 contribute to the growth stimulatory effect of PGE2, unlike EP1, which is growth inhibitory. Indeed, the EP1 antagonists ONO‐8711 and SC51089 increase, rather than inhibit MDCK cell growth. Growth stimulatory effects of ONO‐8711 and SC51089 were observed in the absence of exogenous PGE2. This latter effect was prevented by the cyclooxygenase inhibitor ibuprofen, indicating that EP1 mediated growth inhibition was dependent upon endogenous PGE2. Evidence was obtained that EP1 activation results in the inhibition of Akt signaling, including the observation that 1) ONO‐8711 and SC51089 increase Akt phosphorylation, and 2) MK2206, an Akt inhibitor, prevents the increased growth caused by EP1 antagonists. In addition, evidence was obtained for the involvement of the EGF Receptor (EGFR), including the observation that 1) SC51089 increases the phosphorylation of the EGF Receptor (EGFR), and 2) the EGFR kinase inhibitor AG1478 prevents the growth stimulatory effects of ONO‐8711 and SC51089. These latter results support the hypothesis that EP1 receptor activation also affects signaling via the EGFR. Thus, EP1 receptor pharmacology may prevent aberrant growth associated with a number of renal diseases.

Grant Funding Source: NIH
Insulin‐like growth factor I regulation of FOXO1 in gonadotropes (1012.7)
Authors: Skarra Danalea , Thackray Varykina
Published: June 2021

The transcription factor FOXO1 is important for several aspects of reproductive function, including endometrial decidualization, ovarian follicular maturation, and spermatogenesis. We have previously reported that in pituitary gonadotropes FOXO1 functions as a repressor of both luteinizing hormone beta (Lhb) and follicle stimulating hormone beta (Fshb) transcription, which are critical for reproduction. Insulin‐like growth factor I (IGFI) is a negative regulator of FOXO1 transcriptional activity. Given that FOXO1 can repress Lhb and Fshb transcription and that IGFI stimulation of gonadotrope cells enhances Lhb and Fshb synthesis, we investigated how IGFI regulates FOXO1 activity in gonadotropes in the current study. In LβT2 gonadotrope cells, we determined by western analyses that IGFI induced Ser256 FOXO1 phosphorylation, causing FOXO1 inhibition and cytoplasmic localization as identified by immunofluorescence microscopy. In addition, inhibition of components of the IGFI signaling pathway, such as PI3K or AKT, blocked IGFI‐induced phosphorylation of FOXO1. As the in vivo gonadotrope hormone milieu includes GnRH along with IGFI, we next investigated the effect of GnRH on FOXO1 phosphorylation and subcellular localization. Stimulation of LβT2 cells with GnRH alone induced moderate cytoplasmic localization of FOXO1, although GnRH did not induce phosphorylation of FOXO1 Ser256. Moreover, the GnRH‐induced shuttling of FOXO1 to the cytoplasm was not blocked by inhibition of PI3K activity. We are currently investigating the effects of IGFI and GnRH co‐treatment.

Grant Funding Source: Supported by NIH Grants T32 HD007203 and F32 HD074414 to DVS; R01 HD067448 and U54 HD012303 to VGT.
Soluble IP4 limits NK cell effector functions by controlling PI3K signaling (1013.1)
Authors: Sauer Karsten , Park Eugene , Siegemund Sabine , French Anthony , Wahle Joseph , Sternberg Luise , Rigaud Stephanie , Jonsson Helena , Yokoyama Wayne
Published: June 2021

NK cells are important for cancer immunosurveillance, bone marrow allograft rejection, fighting infections and reproduction. Overcoming their limited efficacy in cancer immunotherapies requires a better understanding of the mechanisms limiting NK cell effector functions. NK cells recognize and kill pathogen‐infected or tumor cells through NK cell receptors (NKR). Two second‐messenger downstream pathways are required for NK cell maturation and function: PIP3‐generation by PI3K, and generation of DAG and IP3 by PLCγ. IP3 has a key signaling role by mobilizing Calcium, but can also be converted into soluble inositol(1,3,4,5)tetrakisphosphate (IP4). IP4 can act as a soluble analog of the PI3K lipid‐product phosphatidylinositol(3,4,5)trisphosphate (PIP3) and control PIP3‐mediated signaling protein membrane recruitment and activation in thymocytes and granulocytes. Here, we show published and unpublished data which suggest that IP4 limits NKR induced IFNγ secretion, granule exocytosis and target‐cell clearance, in part by inhibiting the PIP3 effector‐kinase Akt in NK cells. This identifies IP4 as an important novel regulator of NK cell function, and expands our understanding of the therapeutically important mechanisms dampening NK cell responses. Our results further suggest that PI3K regulation by soluble IP4 is a broadly important signaling paradigm.

Grant Funding Source: Supported by NIH grants AI070845, GM088647, AI089805 & Leukemia & Lymphoma Society Award 1440‐11
A mixed‐methods approach to construct program‐impact pathways and highlight the role of an agricultural and market development program in supporting household food security and dietary diversity among smallholder farmers in Guatemala (1014.9)
Authors: López Cintrón Julio , Peterson Ross , Torres Pablo , Wuth Alicia , Dong Faye , Engeseth Nicki , Greene Jennifer , Helferich William , Andrade Juan
Published: June 2021

There is a critical need to understand what agricultural interventions are most effective in supporting food security, a determinant of nutrition security. We constructed and linked impact pathways based on a mixed‐methods approach to highlight the role of WFP’s Purchase for Progress (P4P), a program that promotes agricultural productivity and connects smallholder farmers to markets, in supporting food security (FS) and dietary diversity (DD). Socioeconomic variables and FS and DD were measured and associated in 271 P4P and 101 control households using a cross‐sectional design in Guatemala. The Most Significant Change, a qualitative methodology, was applied to a subset sample (46 P4P; 11 control) to explain relationship of P4P core tenets and measured variables. Each pathway factor was laid out along the hypothesized PIP using as blueprints P4P’s program theory and current conceptual frameworks linking agriculture, FS and nutrition. Factor inclusion was supported by evidence from three sources: our study, P4P’s monitoring and evaluation, and current literature. A six‐step process integrated information: data weighting, entry, preparation, analysis, interpretation and final integration. P4P promotes household FS and DD among smallholder farmers by enabling four PIPs: income, agricultural productivity via crop diversification and production practices, market access, and empowerment strategies. PIP research illustrates the role of P4P activities in underpinning nutrition security, specifically by supporting FS and DD among smallholder farmers in Guatemala.

Grant Funding Source: Supported by: Ayre international research fellowship (JRL), Hatch (JEA), USDA‐ISE (WGH, NJE, & JEA)
Breast milk docosahexaenoic acid levels from dried vs. liquid samples from mothers in Bangladesh and Malawi (1015.2)
Authors: Harris Kristina , Jimenez Elizabeth , Petri William , Dewey Kathryn , Ashorn Per , Haque Rashidul , Maleta Kenneth , Mangani Charles , Harris William
Published: June 2021

The effect of breast milk DHA (22:6n‐3) levels on infant health outcomes is unclear. Difficulties in collecting, storing and shipping samples from the field impede research in this area. Here, DHA levels in dried milk spots (DMS) and liquid milk (LM) from the same subjects were compared, then milk samples collected by both methods from Malawi and Bangladesh were tested. Validation studies used milk spots (n=5) dried on cards pretreated with an antioxidant (OxyStop®) and stored in the dark for 4 wks at 23°C or at ‐80°C; LM samples were also tested after storage for 1.5 yrs at ‐20°C. DMS samples from 685 Bangladeshi mothers were shipped ambient, and frozen LM samples from 763 Malawian mothers were shipped on dry ice for analysis. Maternal dietary information was not available in either study. DHA levels in LM vs. DMS from the same subjects were strongly correlated (r>0.99; p<0.0001). The DHA content of DMS was unchanged from baseline after 4 weeks at 23°C (0.19±0.14% vs. 0.20±0.15%). Similarly, LM DHA content was stable over 1.5 years at ‐20°C (0.16±0.15% vs. 0.19±0.15%). Malawian mothers had higher milk DHA levels than Bangladeshi mothers (0.73±0.38% vs. 0.39±0.14%; p<0.0001). Breast milk samples can be collected and shipped as DMS without loss of DHA. Differences in milk DHA levels between Malawi and Bangladesh were not due to differences in method of collection. These results suggest a higher DHA intake in mothers in Malawi.
Neonatal survival appears unaffected by timing in the start of breast‐feeding in rural Bangladesh (1015.5)
Authors: Klemm Rolf , Wu Lee , Christian Parul , Shamim Abu Ahmed , Shaikh Saijuddin , Ali Hasmot , Mehra Sucheta , Labrique Alain , Schulze Kerry , West Keith
Published: June 2021

Breast‐feeding initiation in the first hour of life in Nepal and within the first day of life in India has been associated with reduced neonatal mortality. We assessed the association between breast‐feeding initiation time and neonatal mortality in prospective data collected during a cluster‐randomized, controlled trial of antenatal multiple micronutrient vs. iron‐folic acid supplementation in a typical rural area of northern Bangladesh.

Time of breast‐feeding initiation was obtained during home visits at birth, at one month of age, or during verbal autopsies for infants who died before 1‐month of age. Multivariate binomial regression analysis was used to estimate the association between neonatal mortality and breast‐feeding initiation time (<1 h, 1‐23 h, 蠅24 h) among 26,374 breast‐fed singleton newborns surviving to 48 hr.

We found that 26.8%, 63.0%, and 8.7% of newborns were first breast‐fed at <1 h, 1‐23 h, and > 24 h, respectively. Neonatal mortality was not higher among newborns initiating breast feeding at 1‐23 h (RR=0.86; 95%CI: 0.69‐1.08) or 蠅24 h (RR=1.1; 95%CI: 0.84‐1.68) compared with early (<1 h) initiators in unadjusted analysis; nor between infants initiating breast feeding 蠅24 h (RR=1.32; 95%CI: 0.96, 1.80) compared with those initiating at <24 h. Adjusting individually or collectively for low birth weight, preterm birth and/or living standards index did not change the results.

Initiating breast‐feeding within 1 hr, as recommended by WHO, or within 24 h, was not associated with improved neonatal survival in this rural Bangladesh context. Explanatory factors are being explored.
Breast milk correlates of immune protection against early infancy Cryptosporidium infection in a rural Tanzanian cohort (1015.6)
Authors: Pedersen Sarah , Wilkinson Amanda , Andreasen Aura , Kinung'hi Safari , Warhurst David , Urassa Mark , Mkwashapi Denna , Todd Jim , Changalucha John , McDermid Joann
Published: June 2021

Breast milk (BM) offers an important immunological bridge from mothers to infants; but BM immunology is incompletely understood. We aimed to determine how BM cytokines and immunoglobulins (Ig) were associated with infant Cryptosporidium infection in a prospective cohort of 108 mother (39% HIV+)/infant pairs. BM and maternal serum was analyzed at month 1, 2, 3, and 6 postpartum. Greater BM IgA, IgM, IgG1, IgG2, IgG3 and IgG4 levels were consistently associated with lower odds of infant Cryptosporidium infection, but the trend was not significant. Absolute BM cytokine levels did not differ by maternal Cryptosporidium or HIV infection, and BM and serum cytokines were uncorrelated. The BM cytokine score was determined by categorizing BM cytokines (tertiles) and calculating individual scores for the equation: IFNγ + IL2 + IL6 + IL13 ‐ TNFα. Infant Cryptosporidium infection was associated with the BM cytokine score at each time point (OR=0.57; p=0.034), adjusting for breastfeeding practice and maternal Cryptosporidium infection. These results suggest BM cytokines are associated with early infant Cryptosporidium infection independent of current maternal Cryptosporidium infection or breastfeeding practices.

Grant Funding Source: Supported in part by National Science Foundation IGERT
The value of swabbing sore nipples during lactation (1016.1)
Authors: Hartmann Peter , Rowan Marnie , Chia Elisa , Fairclough Kyle , Menon Lalitha , Ashton Elizabeth , Kent Jacqueline
Published: June 2021

This study aimed to provide insight into nipple pain in breastfeeding mothers focusing on the microbiology, treatments and subsequent outcomes. For a 6‐month period, data were retrieved from the lactation consultant records of 489 clients of the Breast Feeding Centre of WA. Nipple pain was identified in 36% of the clients. Nipple swabs were collected from 46% of the clients with nipple pain when infection was clinically suspected as the cause. The rate of detected infection was 61%. Staphylococcus species were present in 90% of the positive cultures. Other infective organisms detected were a variant of the Streptococcus species, Acinetobacter baumannii, Pseudomonas stutzeri and Candida. Targeted treatment was provided for 77% of the mothers who were positive. Antibiotic choice included flucloxacillin alone or with a combination of other antimicrobials or antifungals, cephalexin, or cephalosporin, depending on the sensitivity of the organism grown from the swab to antibiotics. Fluconazole was prescribed when candida was detected. The treatment resulted in the nipple pain resolving or resolved in 71% of cases. We conclude that swabbing painful nipples during lactation can provide successful, targeted treatment.

Grant Funding Source: Supported by Medela, AG
Influences on decision to breastfeed infants (1016.3)
Authors: Coduti Nicoletta , Gregoire Mary , Sowa Diane , Chen Yimin , Diakakis Georgia
Published: June 2021

Factors contributing to mothers’ decisions to breastfeed were explored. Data were collected from 187 mothers delivering at a Midwest medical center, who chose to exclusively breastfeed, were 34% white, 23% black, and 25% Hispanic (mean age: 29). White mothers were more likely (p<.05) to be married (89%) and have a bachelor’s degree or higher (80%) as compared to black (23%, 27%) and Hispanic (52%, 15%) mothers. Mother’s reported the importance (4 pt scale) placed on the baby’s father (m=3.5), her mother (m=3.1), and her friends’ (m=2.4) breastfeeding opinions. Mothers’ scores on the Iowa Infant Feeding Attitude Scale were similar across race (scores 68, 66, 64 out of 85, with higher score indicating stronger attitudes towards breastfeeding). Mothers agreed (5 pt scale) that breastfeeding increased mother‐infant bonding (m=4.7), was ideal food for their infants (4.5), and was more easily digested (4.4). Most mothers, regardless of race, reported that their doctor (72%), their baby’s doctor (78%), and the hospital staff (90%) had favored breastfeeding and more than 70% reported staff were “very helpful” in providing breastfeeding support. Although demographic differences existed among new mothers, those who chose to breastfeed, appear to have similar positive attitudes about the importance of breastfeeding and the support they received.
Distribution of retinol, carotenoids and tocopherols in serum lipoproteins in lactating women: a longitudinal study (1017.10)
Authors: Torres Alexandre , Machado Michele , Silva Danubia , Nunes Juliana , Kamp Fernanda
Published: June 2021

We aimed to investigate the distribution of retinol, carotenoids and tocopherols in serum lipoprotein fractions, and to investigate associations with dietary intake in a longitudinal observational study with Brazilian lactating women. Lactating adults (n=15) were followed from between the weeks 2 to 4 (t1) through to weeks 12 and 14 (t2) postpartum. Dietary intake was assessed through dietary records and a quantitative food frequency questionnaire. Dietary data were analyzed by the Multiple Source Method internet tool (https://msm.dife.de/). Serum vitamins were analyzed by reversed phase HPLC‐DAD‐FL. Levels of carotenoids in serum were comparable to those reported for Brazilian lactating women in other studies. Alpha‐tocoferol, alpha‐carotene, beta‐carotene and lycopene were primarily parted in LDL/VLDL fraction and lutein and zeaxanthin were primarily in HDL fraction. In contrast, retinol was equally distributed between the LDL/VLDL and the HDL/RBP fractions. Both total and HDL‐fraction lutein/zeaxanthin were positively correlated (Pearson) with dietary intake (p< 0.007 and p< 0.005, respectively). Our results indicate that retinol, carotenoids and tocopherols are differently distributed in serum lipoproteins, suggesting that selective mechanisms can account for serum transport of these components in lactating women, with potential consequences to mechanisms of transference into breast milk.

Grant Funding Source: Supported by FAPERJ, CNPq, CAPES (Brazil)
Breastfeeding during late pregnancy did not affect infant breast milk consumption and growth (1017.2)
Authors: Pareja Rossina , Marquis Grace , Penny Mary
Published: June 2021

Objective: The one thousand days window is the most important period when maternal nutrition demands and infant feeding practices affect infant development. We explored if the practice of breastfeeding until the third trimester of pregnancy affects birth outcomes and infant breast milk (BM) consumption and growth. Methods: Between 2009 and 2013, a cohort of 162 pregnant women was followed from the third trimester of pregnancy through 6 months postpartum in a peri‐urban community in Lima, Peru. The cohort included two groups: group 1 (cases) consisted of pregnant women who reported that they continued to breastfeed their child during the third trimester of pregnancy; group 2 (controls) consisted of pregnant women who had not breastfed during their pregnancy or if they did, it was only in the first trimester. The cohort was visited pre‐ and postpartum when toddler and infant 24‐h BM consumption and anthropometry were measured, respectively. Results: We compared 81 case‐control pairs. Of the 49 cases who accepted a prenatal visit, around 60% of the toddlers had 0 g of BM intake during 24 h, even though an average of 4 breastfeeds was observed. No significant difference was found between cases and controls regarding birth weight, birth length, and BM consumption at the 1st, 3rd, and 6th month postpartum (all p>0.10). Conclusion: There was no effect of the practice of breastfeeding until the third trimester of pregnancy on birth outcomes and infant BM consumption or growth during the first six months of life.

Grant Funding Source: Supported by Canadian Institutes of Health Research
Body composition of breastfed infants ő a comparison of bioelectrical impedance spectroscopy and ultrasound assessment (1017.3)
Authors: Geddes Donna , Gridneva Zoya , Hepworth Anna , Tat Lai Ching , Hartmann Peter
Published: June 2021

An accurate non‐invasive methodology to measure infant body composition is required to identify infants at risk of obesity. This study compared bioelectrical impedance spectroscopy (BIS) and ultrasound (US) methods and assessed effect of milk intake on BIS. Percentage Fat Mass (%FM) of 5 and 9 month old healthy, term infants was determined with BIS pre and post a breastfeed using software default calculations. Milk intake was measured by the test‐weigh method. Skin and subcutaneous fat thickness was measured at the tricipital and subscapular sites with US and the measurements were used to predict %FM. Milk intake (mL) was (median [IQR] 64.5 [43.3, 87.0]). Post and pre feed BIS measurements were not significantly different (p=0.29), regardless of milk intake. US %FM predictions (median [IQR] 25.5 [21.8, 28.8]) were consistent with reference values for infant body composition. BIS %FM measurements (median [IQR] 16.7 [14.5,19.4]) were significantly lower than US %FM (p<0.001). Milk intake did not significantly affect BIS readings. Preliminary results indicate that US is an acceptable non‐invasive method for predicting %FM and BIS consistently underestimates %FM.

Grant Funding Source: Medela AG
A comparison of bacterial communities in feces of breastfed infants determined by 454 pyrosequencing and Illumina MiSeq (1017.5)
Authors: Mosely Janae , Williams Janet , Yahvah Katherine , Riley Mara , Settles Matt , Brooker Sarah , Lackey Kimberly , McGuire Mark , McGuire Michelle
Published: June 2021

Because various molecular techniques are used to evaluate microbial community structure in biological samples, understanding if results are comparable among methods is critical. We hypothesized two of the most commonly‐used techniques, 454 pyrosequencing and Illumina MiSeq, similarly describe bacterial communities in breastfed infants’ feces. To test this, DNA from 25 samples was processed using both techniques; universal primers designed to amplify the V1‐V3 region of the 16S rRNA bacterial gene were used. Bacterial community profiles were clustered using Bray‐Curtis dissimilarity and the average linkage algorithm. Of the 15 most abundant genera detected in the samples, only 8 were common between the 2 methods. Diversity was similar (Shannon, P=0.08), but evenness was different between methods (Simpson, P=0.001). Our data somewhat support the hypothesis that these methods produce similar results in terms of diversity; however, the methods differ in terms of overall community composition and evenness. In conclusion, these potential differences need to be considered when comparing bacterial community data across sequencing methods ‐ at least for feces of breastfed infants.
Breastfeeding support increases breastfeeding duration among middle‐ to high‐income women (1017.6)
Authors: Clark Alena , Baker Susan , McGirr Kathryn , Harris Mary , Davalos Deana
Published: June 2021

The objective of the Omega Smart Baby Project was to determine if supplementing pregnant/breastfeeding mothers with DHA would improve infants’ neuropsychological development. One hundred and fifteen women with singleton pregnancies were given either a placebo or DHA supplement of 300 mg a day during the third trimester and first three months of the infant’s life. A breastfeeding peer support program including prenatal visits, hospital and home visits and phone calls throughout the infants’ first year of life was provided with anticipatory breastfeeding guidance to increase breastfeeding duration rates of study participants to then establish the link between DHA and neuropsychological development. Factors that were associated with a significant increase (p<.05) in breastfeeding duration included marital status, mother’s ethnicity, mother’s medical history and delivery type. At three months, 84% of mothers were breastfeeding, 74% at six months and 56% at twelve months; all higher than the current national and Colorado averages. Results indicate that having consistent breastfeeding support during the infant’s first year of life may increase duration rates.

Grant Funding Source: Supported by USDA NRI
Effect of dairy foods vs. calcium and vitamin‐D supplements on bone metabolism: use of 41Ca tracer (1018.12)
Authors: Demmer Elieke , Gertz Erik , Rogers Tara , Hillgonds Darren , Garrod Marge , Van Loan Marta
Published: June 2021

Effect of dairy foods vs calcium & vitamin‐D supplements on bone metabolism: Use of 41Ca tracer E Demmer1, ER Gertz2, T Rogers1, D Hillgonds3, M Garrod2, MD Van Loan2 1. Graduate Group in Nutritional Biology, University of California Davis, Davis, CA 2. USDA/ARS Western Human Nutrition Research Center, Davis, CA 3. Lawrence Livermore National Laboratory, Livermore, CA Calcium(Ca) & vitamin D (D) are essential for bone health but other dietary components may also be important. Dairy products provide a rich supply of Mg, P, K, and protein, all important to bone health. We examined the effect of 4 servings/d milk & yogurt compared to equal intakes of Ca & D from supplements on bone metabolism. Twelve healthy postmenopausal women, who were low‐moderate dairy consumers, completed a randomized crossover trial with two 6 wk interventions separated by a 6 wk washout period. Six months prior to intervention women were dosed with 41Ca to label the skeleton. 24‐hr urine samples were analyzed for 41Ca/40Ca using accelerator mass spectrometry. Both interventions resulted in a significant decline (p < 0.0001) of Ca lost from the skeleton. Reduced resorption for supplement (p=0.0034) and dairy (p= 0.0002) groups was confirmed by CTx. Formation (BAP) significantly increased (p=0.032) in the dairy group only. Ca intake for the dairy group was significantly less (‐120mg/d) than that consumed by supplements, this difference can be attributed to other dietary Ca sources, e.g. increased vegetable and grain intake in the supplement group. Our results suggest that the nutrient‐rich composition of milk and yogurt may be more effective in maintaining bone health in healthy postmenopausal women compared to Ca and D supplements alone.

Funding: Dairy Research Institute, California Dairy Council, USDA‐ARS‐Western Human Nutrition Research Center

Grant Funding Source: Dairy Research Institute, California Dairy Council, USDA‐ARS‐Western Human Nutrition Research Center