bluuebunny/crossref_metadata_2025 huggingface dataset:
Imperative Role of Macrophage in Maintaining Systemic Energy Homeostasis
Authors: Lee Bonggi , Qiao Liping , Kinney Brice , Shao Jianhua
Published: June 2021

Macrophages are residential immune cells and present in almost all tissues. Increased macrophage infiltration in white adipose tissues (WAT) has been recognized as a pro‐inflammatory factor causing insulin resistance in obesity. However, the functions of macrophage in systemic energy metabolism, particularly under non‐obese conditions, are largely unknown. By conditional expressing of diphtheria toxin (DT) receptor and DT administration, we depleted macrophages in mice and studied the effects on energy metabolism. DT injection efficiently depleted macrophages. We observed robustly reduced body weight with a significant decrease in body fat and food intake in DT‐injected mice. Those phenotypes were recovered when we stop injecting DT. Interestingly, macrophage depletion even reduced energy expenditure during dark cycle, suggesting that decrease of body fat is mainly due to reduced food intake. As a potential factor related to altered energy balance, strikingly high levels of inflammatory cytokines were detected in circulation as well as their expression in multiple tissues including hypothalamus, WAT, and liver of macrophage‐depleted mice. Paradoxically, insulin sensitivity was not altered despite increased systemic inflammation. Together, our results indicate that macrophage play an essential role in regulating energy homeostasis under non‐obese conditions.
Adiponectin and leptin secretion are differentially modulated in subcutaneous and visceral adipose tissue by endoplasmic reticulum stress
Authors: Torre-Villalvazo Ivan , Bunt Ana E , Torres Nimbe , Tovar Armando R
Published: June 2021

Obesity is associated with altered adipokine secretion but the underlying mechanisms responsible for this phenomenon remains unknown. Endoplasmic reticulum stress (ERS) is common alteration in several cell types during obesity.

Objective

To evaluate whether ERS alters adiponectin and leptin production in subcutaneus (SAT) and viceral (VAT) adipose tissue in mice and in cultured adipocytes.

Methods

Mice were fed chow diet supplemented with pioglitazone (120mg/kg) for 2 w, in order to stimulate adipokine production and injected with tunicamicyn (2μg/g body weight) for 8 or 24h before euthanasia. For in vitro analysis, primary SAT and VAT adipocytes were cultured with pioglitazone with or without tunicamicyn for 8 or 24h.

Results

ATF6 and BiP mRNA increased in SAT and VAT of mice injected with tunicamicyn and in cultured adipocytes but at higher magnitude in VAT. Pioglitazone augmented perilipin, SREBP1 and SCD1 mRNA content as expected but interestingly, tunicamicyn reduced this induction. Adiponectin content in adipose tissue and serum was dramatically reduced in mice injected with tunicamicyn and leptin increased.

Conclusions

Tunicamicyn induces ERS in both adipose depots but at higher magnitude in VAT. ERS impairs the pioglitazone effect on adipose tissue gene expression. ERS reduces adiponectin secretion but increases leptin production in adipose tissue. This work is supported by CONACyT (84757).
A Comparison of Nitrophorin 3 Between Wild‐type and Native Forms
Authors: Childers Kenneth Craig
Published: June 2021

Rhodnius prolixus, better known as the kissing bug, is a blood‐sucking insect that utilizes a nitric oxide‐carrying protein as a means to obtain its meal through vasodilation, slowing platelet aggregation and strong histamine binding. The bug stores this nitrophorin protein within its salivary glands at low pH and is activated once released into the victim's blood. At present, four nitrophorin proteins have been discovered and fully sequenced, having been labeled NP1‐NP4 in order of decreasing abundance. NP3 is the only one of the four proteins which has not yet been characterized by x‐ray crystallography. This study will focus specifically on NP3 by comparing its wild‐type and native forms. Thus far, both forms have been cloned and expressed in E. coli and purified with sonication, dialysis and column chromatography. Throughout this procedure, it has been found that, out of all four of the nitrophorin proteins, NP3 remains one of the more difficult to isolate. However, with the recent success in growths of the native and wild‐type forms, the lab remains hopeful that this breakthrough can lead to point mutations within the protein, as they have with the other three nitrophorins.

Source of support:

Department of Biochemistry and Molecular Biophysics, University of Arizona, Tucson, 85726
Measurement of microcantilever spring constants for probing receptor‐ligand bonding
Authors: liu yang , Tees David
Published: June 2021

The force dependence of receptor–ligand bonding has been extensively studied in biophysics. Microcantilevers are a type of spring‐based force sensor and their spring constants were characterized using different methods to check that the measurements were consistent. Microcantilevers made from E‐glass fibers with a nominal diameter of 4 μm and lengths from 3–7 mm were mounted in viewing chambers and imaged under a microscope with a 100× oil immersion lens. Multiple sets of images for each microcantilever were captured at 50–800 frames per second and analyzed using custom LabVIEW IMAQ image processing program. The microcantilever intensity profile was used to find the edges (represented by two intensity troughs). The equipartition theorem was used to find spring constant values from displacements of the edges in the time domain. These were found to decrease with increasing cantilever length as expected from elastic theory. Fluctuations were also studied in frequency domain. The Power Spectral Density of the microcantilever displacements was fitted to a Lorentzian. The spring constants calculated from the Lorentzian parameters were consistent with the results from the equipartition theorem. This work was supported with funding from the Ohio University Biomimetic Nanoscience and NanoTechnology Program.
Differences in susceptibility to nutrient‐induced cell death between primary and immortalized Leigh Syndrome French Canadian type (LSFC) patient fibroblasts
Authors: Rivard Marie-Eve , Burelle Yan , Bemeur Chantal , Villeneuve Louis , Coderre Lise , Rosiers Christine Des
Published: June 2021

LSFC is a monogenic metabolic disease resulting from a mutation in the leucine‐rich pentatricopeptide repeat‐containing (LRPPRC) gene. It is characterized by cytochrome c oxidase (COX) deficiency and episodes of lactic acidosis leading to death at an early age. Recently, we reported that primary (P) LSFC fibroblasts were more susceptible than controls to necrosis induced by nutrient overload (palmitate 1 mM and lactate 10 mM), an effect associated with a lower [ATP] (FASEB J 2011 25:722.15). In this study, we compared P and immortalized (I) LSFC and control fibroblasts. Under basal conditions, control P and I cells displayed similar characteristics regarding (i) LRPPRC localization (immunocytochemistry) and content (Western) as well as (ii) COX activity. Both these parameters showed the expected decrease in LSFC P and I cells. However, compared to P cells, I cells from both groups had higher citrate synthase activity (~25%) and lower [ATP] (~40%). Accordingly, during nutrient overload, I cells were more susceptible than P cells to both necrosis and apoptosis. While this was observed for control and LSFC cells, LSFC I cells remain more susceptible to necrosis compared to their control counterpart. Collectively, our results highlight differences between P and I cells that ought to be considered for data interpretation and study design. (Supported by: Association de l'acidose lactique and CIHR Emerging Team Grant)
Asymmetric cortical extension leads to asymmetric cell division in Drosophila neuroblasts
Authors: Connell Marisa , Cabernard Clemens , Ricketson Derek , Doe Chris Q. , Prehoda Kenneth E.
Published: June 2021

Drosophila neuroblasts divide asymmetrically to produce two daughter cells of different sizes: a larger neuroblast and a smaller ganglion mother cell (GMC). Live imaging of neuroblasts demonstrates that they divide asymmetrically due to the localization of myosin to the basal pole of the neuroblast (the side that will become the smaller GMC) during anaphase. We hypothesized that this asymmetric myosin localization would lead to reduced extension at the basal pole while extension at the apical pole would not be restricted. We measured the position of the apical and the basal cortex in neuroblasts and observed preferential displacement of the apical cortex that becomes the larger daughter cell during anaphase, effectively shifting the cleavage furrow toward the smaller daughter cell. In neuroblasts the apical pole extends ~3 times more than the basal pole producing an apical daughter cell (neuroblast) that is ~2 times larger than the basal daughter cell (GMC). In mutants that have lost the basal myosin domain, Pins (Partner of Inscuteable) and Gβ, there is equal cortical extension at both poles and the division produces daughter cells of equal size. This asymmetry is not due to unequal addition of membrane at the apical pole as the amount of surface area created during mitosis (determined by 3D reconstruction of the cell) is insignificant compared to the difference in surface area between the daughter cells. We propose a model in which contraction‐driven asymmetric polar extension of the neuroblast cortex during anaphase contributes to asymmetric furrow position and daughter cell size. National Institutes of Health Grant 068032.
Hydrophobic and electrostatic interactions anchor perilipin 2 to the surface of cytosolic lipid droplets
Authors: Sletten Arthur C. , Seline Alison E. , Listenberger Laura L.
Published: June 2021

All eukaryotic organisms store excess lipid in intracellular lipid droplets. These dynamic structures are associated with and regulated by numerous proteins. One such protein, perilipin 2, is present on lipid droplets in most lipid storing cells. However, the mechanism by which perilipin 2 localizes and remains anchored to the lipid droplet surface is unknown. The objective of our study was to determine the roles of hydrophobic and electrostatic interactions in perilipin 2 localization. Lipid droplets coated with perilipin 2 were incubated with reagents designed to disrupt either electrostatic or hydrophobic interactions. We show that disrupting hydrophobic interactions, between proteins and surface phospholipids, causes perilipin 2 to dissociate from the lipid droplet. Unexpectedly, disturbing electrostatic attractions between perilipin 2 and surface phospholipids also compromised binding. Future studies aim to identify the specific characteristics of the lipid droplet surface that mediate the binding of perilipin 2 and other lipid droplet proteins. This work was funded by the Research Corporation for Science Advancement (LL) and through the generous support of Dr. Elizabeth Nabel (ACS).
Expression of PMCA4a in the Extratesticular Pathway and Accessory Organs of the Mouse
Authors: Patel Ramkrishna , Stabley Deborah , Strehler Emanuel , Martin-DeLeon Patricia
Published: June 2021

Plasma Membrane Ca2+ ATPase isoform 4b (PMCA4b) is the primary Ca2+ efflux pump in murine sperm where it regulates motility. In Pmca4 null sperm hyperactivated motility is lost, resulting in infertility. We have shown that PMCA4b interacts with CASK in regulating Ca2+ homeostasis and motility. Recently, it has been shown that PMCA4a and 4b are expressed in all bovine epididymal (EPL) regions, with increasing amounts of 4a distally and only 4b in testis. These findings suggest that PMCA4a and b are acquired by sperm during EPL maturation. Here we show, via RT‐PCR, that murine Pmca4b mRNA is expressed uniformly in testis and epididymis (EP) and 4a differentially in the EP. Western confirmed the RT‐PCR results showing that PMCA4a is most abundant in testis and cauda EP. Immunoprecipitation using pan‐PMCA4 antibody showed 4b and 4a in caput and corpus EP and 4a in cauda, seminal vesicle (SV), and vas deferens (VD). Western revealed an ~4 fold increase of 4a in caudal, compared to, caput sperm and confirmed its presence in the VD and SV. Importantly, PMCA4a was seen in sperm‐free EPL luminal fluid, suggesting that it is secreted, and acquired by sperm via epididymosomes. Since PMCA4a and 4b have different kinetic properties for Ca2+ transport, our study suggests for the first time that murine sperm possess PMCA4a which has a higher Ca2+ turnover, better facilitating capacitation events in the female tract. Funding: NIH‐RO3 HD061637.
Formation of integral membrane protein oligomers
Authors: Lai Yi-chun , Renthal Robert
Published: June 2021

Many transmembrane (TM) proteins form oligomeric structures involving strong homomeric or heteromeric associations with other TM protein subunits. Little is known about the assembly mechanisms of these oligomers. We now report a technique for measuring the association of TM proteins in vitro. Bacteriorhodopsin fragments (2 and 5 TM helices) that are known to associate in detergent/lipid bicelles and form a native structure were separately inserted into nanolipoprotein particles (NLPs) using an E. coli cell‐free expression system. Each fragment contained one engineered cysteine, positioned so that disulfides form when the fragments correctly associate. The fragment/NLP complexes were mixed and disulfide crosslinking was initiated by Cu(II). No crosslinks between 2 and 5 TM helix fragments were detected. However, if the NLP complexes were mixed with bicelles prior to Cu(II) treatment, 2 to 5 TM helix crosslinks were observed. Thus, detergent/lipid bicelles open NLPs and permit protein mixing. The association constant for oligomer formation can be determined from the rate of crosslinking at varying protein concentrations. Future applications of this method include measuring association constants of protomers that form both homo‐ and hetero‐oligomeric channels (e.g. connexins, ligand‐gated ion channels), and studies of interactions of monomers with membrane chaperones.
Pannexin 1 knockdown in metastatic melanoma cells induces cell differentiation into a melanocytic phenotype decreasing tumor size and metastasis in vivo
Authors: Penuela Silvia , Gyenis Laszlo , Ablack Amber , Churko Jared , Berger Amy , Lewis John , Litchfield David , Laird Dale
Published: June 2021

Pannexin 1 (Panx1) is a channel‐forming glycoprotein expressed in different cell types of mammalian skin. We studied the role of Panx1 in melanoma tumorigenesis and metastasis since the mouse melanocyte line CRL‐2770 showed low levels of Panx1 expression, while Panx1 in isogenic melanoma cell lines (B16‐F0, ‐F10 and ‐BL6) was increasingly up‐regulated according to qPCR and Western blot assays. Panx1 shRNA knockdown generated stable BL6 cell lines (Panx1‐KD) that showed a marked increase in melanocyte‐like cell characteristics, including higher melanin production, decreased cell migration and enhanced formation of cellular projections, while compromising Panx1 dye uptake channel function. Western blotting and proteomic analyses using 2D‐SDS‐PAGE gels/mass spectroscopy identified vimentin and beta‐catenin as some of the markers of malignant melanoma that were down‐regulated in Panx1‐KD cells. In vivo, Panx1‐KD cells were implanted on chorioallantoic membranes of day 10 avian embryos. After seven days, the excised Panx1‐KD tumors were significantly smaller than controls and metastasis to the liver was significantly reduced as quantified by mouse‐Alu qPCR of the excised embryonic organs. These data suggests that Panx1 may play a role in skin melanocytes that is potentially dysregulated upon malignant transformation in metastatic melanomas. Supported by the Canadian Institutes of Health Research.
A Novel Mechanism of Trancytosis of Drug Carriers Across Gastrointestinal Epithelial Cells Mediated by ICAM‐1
Authors: Ghaffarian Rasa , Bhowmick Tridib , Muro Silvia
Published: June 2021

We recently showed that intercellular adhesion molecule‐1 (ICAM‐1), a transmembrane glycoprotein expressed on epithelial and other cell types, supports transport of drug nanocarriers (NCs) across gastrointestinal (GI) epithelial cells. To elucidate the mechanism of transport, 100‐nm NCs coated with 125I‐anti‐ICAM (anti‐ICAM NCs) were traced across Caco‐2 monolayers grown on porous filters. Transport was specific for ICAM‐1 (715±35 anti‐ICAM NCs/cell versus 18‐fold reduction for IgG NCs; 24h) and abolished in the presence of free anti‐ICAM but not IgG, implying Fc‐independence. Ruling out the paracellular route associated to opening of the cell junctions, transport of anti‐ICAM NCs did not lower the transepithelial electrical resistance over 48‐h or increase protein (albumin) leakage across cells, in contrast to H2O2 used as a positive control. Transcytosis was assessed using inhibitors of clathrin pits (monodansylcadeaverine), caveoli (filipin), macropinocytosis and cell adhesion molecule (CAM) endocytosis (EIPA), or macropinocytosis alone (wortmannnin). Only EIPA reduced transport of anti‐ICAM NCs, without affecting transport of IgG NC or albumin, indicating CAM‐mediated transcytosis. These results were confirmed by transmission electron microscopy. Therefore, ICAM‐1‐targeting may provide clathrin‐ and caveolar‐independent mode of transcytosis in GI epithelial cells.
Alteration of heparan sulfate 2‐O‐sulfation in endothelial cells enhances neutrophil infiltration in mice
Authors: Xu Ding , Axelsson Jakob , Kang Bit Na , Sriramarao P , Handel Tracy M. , Ley Klaus , Esko Jeffrey D
Published: June 2021

Inactivation of the enzyme N‐acetylglucosamine N‐deacetylase–N‐sulfotransferase‐ 1 (Ndst1) in endothelial cells results in diminished overall sulfation of heparan sulfate and reduced neutrophil infiltration in various inflammation models. In this report, we examined the contribution of uronic acid 2‐O‐sulfation to neutrophil infiltration by inactivation of uronyl 2‐O‐sulfotransferase (Hs2st) in endothelial cells. Surprisingly, deletion of Hs2st had the opposite effect of deleting Ndst1, resulting in accentuated neutrophil trafficking in acute inflammatory models. Enhanced neutrophil infiltration was partially due to reduced rolling velocity in vitro and in vivo, correlating with stronger binding of L‐selectin to mutant endothelial cells. Hs2st‐deficient endothelial cells also displayed greatly enhanced binding of interleukin‐8. The gain‐of‐function phenotype in Hs2st‐deficient mice apparently results from enhanced glucosamine N‐sulfation and 6‐O‐sulfation that occurs with inhibition of 2‐O‐sulfation. Thus, specific sulfation patterns of endothelial heparan sulfate can have distinct effects on neutrophil recruitment during inflammation, a property that might be exploited for treating inflammatory disorders.
Systemic chemical proteomics based target identification and validation of OMe‐Syn, a new anti‐angiogenic natural small molecule
Authors: Kim Nam Hee , Pham Ngoc , Quinn Ronald , Kwon Ho Jeong
Published: June 2021

Angiogenesis is a new blood vessel formation from existing parent vessel through the generation of endothelial cells. R‐(‐)‐O‐methylsynephrine (OMe‐Syn) is a natural product isolated from a plant of the Rutaceae family. Recently, we found that OMe‐Syn inhibited vascular endothelial growth factor (VEGF)‐induced angiogenesis both in vitro and in vivo. To investigate the mode of action of the compound, identification of the target protein of OMe‐Syn was carried out by using affinity based phage display biopanning. T7 phages encoding human cDNA libraries were used for affinity selection of OMe‐Syn binding protein. After 4th round of biopanning, the OMe‐Syn binding protein (OBP) was discovered as the high affinity binding protein of the compound. Furthermore, cytosolic proteome of OMe‐Syn treated cells was analyzed using differential gel electrophoresis (DIGE) and MALDI‐TOF MS analysis to investigate the mechanism of the compound. Among the proteins affected by OMe‐Syn, proteins responsible for anti‐angiogenic activity of OMe‐Syn are identified and under investigation for their relevancy to the biological activity of OMe‐Syn. Systemic investigation with chemical proteomics on mode of action of bioactive small molecules will provide new insights into the molecular mechanism underlying the biological activity of OMe‐Syn and its target protein. This study is supported by self‐research funding.
Modulation of microRNA miR‐29c in a novel cross‐talk between mTOR complex 1 and Angiotensin II type 2 receptor AT2R: an adaptive mechanism in over‐nutrition
Authors: Pulakat Lakshmi , Gul Rukhsana , Arnold Shannon , DeMarco Vincent , Sowers James R.
Published: June 2021

The microRNA miR‐29c that inhibits INSIG‐1 and insulin (INS) metabolic signaling is up‐regulated in tissues from diabetic animals and plasma of diabetic patients. Our analysis by MiRecords identified a novel target for miR‐29, the Angiotensin II type 2 receptor AT2R. Since AT2R is cardio‐protective, we posited that conditions that activate mTORC1 in cardiac tissue can down‐regulate miR‐29c and thus up‐regulate AT2R. In HL‐1 cardiomyocytes exposed to INS (100nM), mTORC1 was activated as evidenced by phosphorylation (p) of S6K1 (pThr389) and 4E‐BP (pThr37/Thr46), miR‐29c was down‐regulated, and AT2R protein, but not mRNA, was up‐regulated (p < 0.05). mTORC1 inhibitors Rapamycin (Rap: 10nM) and Dexamethasone (Dexa:5μM) ablated mTORC1, up‐regulated miR‐29c and disrupted mTOR→miR‐29→AT2R pathway (p < 0.05). Conversely, a novel AT2R agonist Novokinin (Nov: 1μM) normalized excess mTORC1 activation, but also reduced miR‐29c (p < 0.05) in HL‐1 cells and in cardiac tissues of Zucker obese (ZO rats: 12‐week) subjected to a 9‐day Nov infusion (200μg•kg−1•day−1). Further, Nov improved myocardial performance index in ZO rats. Thus, commonly used mTORC1 inhibitors Rap and Dexa up‐regulate miR‐29 and exacerbate inhibition of INS metabolic signaling whereas AT2R agonist Nov attenuates excess mTORC1 without inducing miR‐29 up‐regulation and subsequent exacerbation of insulin resistance.
Undergraduate Laboratory Renaissance: research integration across the entire Biochemistry laboratory curriculum
Authors: Roecklein-Canfield Jennifer , Gurney Richard , Lee Nancy , Soltzberg Leonard
Published: June 2021

Traditional undergraduate chemical laboratory experiments do not prepare students adequately for performing research in graduate programs or industry. To address this need, we have implemented a fully research integrated laboratory curriculum across the undergraduate Chemistry major, beginning in the second semester of the freshman year. Students begin research integration in the first semester Organic Chemistry laboratory that continues right through to the senior capstone independent research experience. Students are actively engaged in the research agendas of each of the faculty members teaching their courses. Our program includes collaborations with biology faculty in selective courses in biochemistry and molecular biology as well. We describe here the Simmons Chemistry Laboratory Renaissance including the methods of switching from a traditional to a research integrated curriculum and the direct and indirect assessments of the program. We will illustrate the process for the traditional biochemistry track. We also describe a successful collaboration between the Genomics Education Partnership at Washington University in St. Louis and the biochemistry faculty to integrate novel genomics and bioinformatics research into the program.
Genetic influence on fatty acid composition of human breastmilk
Authors: Cheatham Carol L
Published: June 2021

Objective

The cognitive advantage conferred by breastfeeding may be dependent on maternal FADS2 genotype. In a Canadian sample (Xie & Innis, 2008), fatty acid content of human milk related to genotype at rs174575 on the FADS2 gene. This study was undertaken to explore this in a sample from the USA.

Methods

Breastfeeding dyads were enrolled when infant was 3–4 months of age (n=200). Mothers collected a morning sample by emptying one entire breast, agitating, aliquoting, and transporting to the lab on ice. Samples were stored at −20 F until lipids were extracted and saponified. Fatty acids were trans‐methylated to methyl esters that were analyzed using capillary gas chromatography. DNA was extracted from saliva using a QIAcube robotic station (Qiagen), as per manufacturer's protocol. 20 ng DNA was used with validated primers from Applied Biosystems. The real time PCR assay was run on an Eppendorf thermal cycler.

Results

Maternal genotype is related to fatty acids: homozygous recessive (GG) had lower fatty acid levels than wildtype (CC). Levels of arachidonic acid, docosapentaenoic acid (n‐3), and docosahexaenoic acid reached statistical significance (p<0.05).

Conclusion

The desaturases used in biosynthesis of fatty acids from their precursors may be in limited supply in certain genotypes. These mothers should insure exogenous fatty acids are being consumed.

Support: Nutrition Obesity Research Center, UNC
Identification of the Variability of Metabolites in Human Milk using Gas Chromatography‐Mass Spectrometry (GC‐MS) Profiling
Authors: Hartmann Peter , Piper Kristen M , Lui James K , Rawlinson Catherine , Trengove Robert , Trengove Naomi J
Published: June 2021

A significant amount of research has been conducted into the macronutrient content of human milk. As such, the variation of milk components such as fat, protein and lactose have been well defined, however, little is known about the metabolites in human milk. Our preliminary investigation has detected approximately 200 metabolites in human milk. In this study we investigated the metabolites present in milk using GC‐MS profiling. Mothers (n=10) of healthy infants (1–18 months) provided approximately 5ml of freshly expressed breastmilk for analysis. Samples were mixed with methanol and snap frozen at −80ºC. Metabolites were extracted and GC‐MS was performed to obtain a metabolite profile for each sample. Data analysis was performed using Analyzer Pro® software. Whilst many of the metabolites in these profiles are yet to be identified, we were able to determine which of the metabolites exhibited the greatest variation. The profiling of these metabolites provides a platform for future research into the metabolic pathways that exhibit the greatest variation in the lactating human breast. These techniques will allow further elucidation of the physiology of the lactating human breast and have the potential to assist in the use of milk samples for the diagnosis of lactation difficulties such as mastitis and inadequate milk supply. Funded by an unrestricted research grant from Medela AG, Switzerland.
Human Milk Oligosaccharides Are Differentially Metabolized In Neonatal Rats
Authors: Jantscher-Krenn Evelyn , Marx Carolin , Bode Lars
Published: June 2021

Newborn infants ingest high amounts of Human Milk Oligosaccharides (HMO) with their mother's milk, but the exact metabolic fate and bioavailability remain unknown. Here, we investigated the metabolism of orally administered HMO in 3d old neonatal rats. Pups were gavaged with formula with or without HMO (15mg/mL). Blood, urine and intestines were collected at different times post feeding. Intestines were divided into 5 sections of equal length. HMO in the different tissues were analyzed by HPLC‐FL, MS and TLC. Serum and urine contained mostly 3′SL (one of the few oligosaccharides in rat milk) but no other HMO, suggesting low absorption of non‐rat oligosaccharides. HMO composition in the intestine changed significantly over time and between different sections. Most strikingly, the percentage of lacto‐N‐fucopentaose 1 increased from 17% of total HMO ingested to 40% and 60% of HMO recovered from jejunal sections after 4 and 8hrs, respectively. Generally, higher‐mass HMO were enriched over smaller HMO like 2′‐fucosyllactose or lacto‐N‐tetraose. This indicates that structure‐specific HMO degradation already occurs in the neonatal rat's small intestine. Based on these results, our previous notion that HMO reach the colon in the same composition as in human milk may need to be reconsidered, at least for studies in some animal models. How these results translate to human infants needs further investigation.
Improvement of bioactivity of alpha‐lactalbumin through Maillard reaction with dextran
Authors: Hong Seung-Taek , Ha Young-Min , Nam Mi-Hyun , Lee Kwang-Won
Published: June 2021

α‐Lactalbumin (α‐LA) is an important protein present in the milk of many mammalian species. It is a Ca2+‐binding protein with 4 disulfide bonds. α‐LA and its hydrolysate has been reported to have many physiological functions, such as antimicrobial activity, antiulcer activity and antihypertensive action. However, it was also reported that α‐LA had allergy‐inducing agent. In this study, we tried to synthesize an improved α‐LA through Maillard reaction with polysaccharide dextran (D) which is also well known for its antithrombotic effect. Maillard reaction occurs routinely in cooking and its products are considered safe. α‐LA and D were dry‐heated at 60 °C and 79% relative humidity for 1 week. SDS‐PAGE analysis and absorbance measurements were used to verify the occurrence of the conjugate formation. Antioxidant assays are performed, and immune‐modulating effects are estimated by nitric oxide (NO) production in RAW 264.7 macrophages stimulated with lipopolysaccharide (LPS). Data showed that α‐LA was successfully conjugated with dextran. D+LA conjugate have shown antioxidant property in a glycation reaction‐time‐dependant manner. Moreover, D+LA significantly inhibited the overproduction of NO compared with the only α‐LA treated sample. Therefore, our study suggest that glycation of α‐LA with dextran (D+LA) might be a useful method for improving some physiological functions of α‐LA.

Grant Funding Source: Korea Food Research Institute, Korea
Effects of a Low‐Fat Diet on the Anti‐inflammatory Interleukin Levels of Older Adults
Authors: Wall-Bassett Elizabeth D , Maddy LaDonna , Tharrington India , Macesich Jennifer , Harper Bradley M , Heidal Kimberly , Pofahl Walter E , Gordon Scott E
Published: June 2021

Immunosenescence involves changes on the cellular and molecular levels of the immune system, and is associated with aging. Higher incidence of autoimmune disorders and other inflammatory conditions, as well as increased rates of infectious disease, cancer, and mortality have been linked to this condition. Proinflammatory interleukins (IL‐6) have been shown to increase with age, while anti‐inflammatory interleukins (IL‐4, IL‐10) decrease. Additionally, a low‐fat diet has been correlated with lower IL‐6 levels in older adults. The purpose of this study was to examine the effects of fat intake on IL‐4 and IL‐10 levels in older adults.

IL‐4 and IL‐10 concentrations were analyzed from venous samples of 10 older adults (46–85 yrs) and compared to venous samples of 9 younger adults (18–45 yrs). Five older adults were counseled to consume a high‐carbohydrate, low‐fat diet for three days prior. All other subjects were instructed to consume their normal diet. Contrary to our hypothesis, a low‐fat diet did not result in increased levels of IL‐4 or IL‐10 levels, and no reversal of immunosenescence. Further investigation is warranted to investigate contributing factors to changes in immunosenescence. This research was supported by the East Carolina University Division of Research and Graduate Studies.
Evaluation of a telephone‐delivered dietary behavior intervention for ovarian cancer survivors
Authors: del Rocio Berglund Maria , Paxton Raheem J , Garcia-Prieto Celia , Hernandez Mike , Hajek Richard A , Handy Beverly Carol , Brown Jubilee , Jones Lovell A
Published: June 2021

BACKGROUND

To date, few dietary interventions have been conducted among ovarian cancer survivors. There is an important need to evaluate feasible and effective means of delivering evidence‐based dietary behavior programs to cancer survivors, including telephone‐delivered counseling interventions (TDCI).

METHODS

This randomized parallel‐group study, evaluated a TDCI dietary change targeting ovarian cancer survivors. 51 women were randomized to a plant‐based (PB) diet or a modified NCI diet supplemented with a soy‐based beverage and encapsulated fruit & vegetable concentrates (FVJCs). Women received a workbook and 14 calls over 6 months. Changes in dietary intake and health‐related quality of life (HRQOL) were assessed with paired t‐tests.

RESULTS

At 6‐mo the FVJC group exhibited higher adherence to the dietary goals of ≥ 5 servings/day of fruits & vegetables, ≥ 25 g/day fiber, & ≤ 20% of kcal from fat (33%, 32%, and 21% adherence, respectively). Participants in the PB group adhered most to the recommendation of ≥ 5 servings/day of vegetables (47%), and ≥ 2 daily 8‐ounce servings of juice (37%) and adhered less to the recommendations of ≥ 30 g fiber/day (26%), ≤ 20% of kcal from fat (16%), and ≥ 3 servings of fruit/day (11%). No changes in HRQOL were observed.

CONCLUSIONS

This feasibility trial adds to the currently limited number of TDCI studies targeting dietary change.

FUNDING: This research was supported in part by donations from NSA, LLC, Collierville, TN, a NCI grants K01CA158000 (to RJP), and by the NIH through MD Anderson's Cancer Center Support Grant CA016672.
Dietary intake in women consuming three supplements with identical micronutrient content
Authors: Rodriguez Fabiola Mejia , Neufeld Lynnette M , Quezada-Sanchez Amado David , Garcia-Guerra Armando F
Published: June 2021

Objective

to estimate energy, protein, iron, zinc, and folate intake from diet only and diet+supplement in women participants in a randomized controlled supplementation trial in Mexico.

Methods

Communities randomly assigned (18/suppl) to receive a fortified beverage (FB), micronutrient tablet, or micronutrient powder. Pregnant women (<25 wks), beneficiaries of Oportunidades were eligible to participate. Dietary intake was assessed by food frequency questionnaire (FFQ, previous month) 37 wks preg, 1 and 3 mo postpartum. Supplements were delivered and consumption estimated by observation (first 9 mo) then weekly (maternal report) for the rest of the trial. Comparisons among supplementation groups were using statistical analyses for cluster randomized trials.

Results

694 women began supplementation (FB =224, T=235, MNP=235) and 571 (82%) finished the study; there were no significant differences among groups at baseline. Total protein intake from diet+supplements was higher in the FB (p<0.05), with no difference in diet or total energy or micronutrients.

Conclusions

Energy intake is high and likely overestimated by our FFQ; but we have no reason to believe that overestimation varies by group. The additional protein from FB in this population may not be needed as dietary intakes appear adequate.

The Oportunidades program financed this study and holds the rights to the data presented.
Popcorn snack more satiating than almonds, party mix or pretzels
Authors: Reimers Kristin J , Lowczyk Ursula T. , Meyer Michael C.
Published: June 2021

This study compared satiety of whole grain 94% fat free microwave popcorn, dry roasted almonds, party mix (a mix of ready‐to‐eat cereal squares) and pretzels. Eucaloric (100 kcal) portions of these foods where tested in a counterbalanced, within subject design, with 29 normal weight participants (9 males and 20 females, ages 20–50 years). Participants consumed a standard breakfast followed three hours later by the test snack. Hunger, fullness, thirst, desire for a snack and general mood were recorded on 11‐point scales before and 30 minutes after the snack. Overall liking, appearance, flavor, texture and satisfaction were rated on 9‐point hedonic scales. Popcorn consumption resulted in less hunger, more fullness and less interest in a snack than almonds, party mix or pretzels (p<0.05) 30 minutes post consumption. These results support previous research showing popcorn is more satiating than other popular snacks. The satiety attribute, combined with popcorn's contribution to whole grain and fiber intakes, supports the consumption of low fat popcorn as a snack that can add to a healthy dietary pattern.

Supported by ConAgra Foods
Effect of a beverage containing dextrin fiber on satiety and energy intake in healthy volunteers
Authors: Park Sonhee Choi , Boza Julio , LaSalle Mark , Striegel Don , Hull Sarah , Re Roberta
Published: June 2021

The aim of this study was to assess satiety effects of a beverage containing dextrin fiber (FIBER; 7.44 g/330 ml; 14.88 g/d) compared to an isocaloric, dextrin fiber free beverage (Placebo) and a No Beverage Control (NBC) in a randomized, controlled, crossover study in healthy volunteers. Total caloric content of the beverage was 35.5 kcal/330 ml; 71 kcal/d. Satiety was measured by Visual Analogue Scale (VAS) every 15 min for a 4‐h test period and ad libitum energy intake at the next meal in an acute test day. A 2‐week adaptation feeding was carried out between two acute test days. Among 36 subjects enrolled, 32 successfully completed the study (mean age: 44 years; BMI: 25.4 kg/m2). Subjects were asked to consume the 1st serving with the breakfast and the 2nd as a mid‐morning snack drink. Energy intake data were analyzed via paired T‐test and VAS scores using analysis of variance (ANOVA), modelfit via F‐test and stepwise multiple regression. Subjects did not consume test beverage during NBC phase. Consuming 14.88 g FIBER/d did not significantly increase satiety feelings or reduce energy intake from the next meal before or after the 2‐week adaptation period as compared to placebo or NBC when incorporated into a beverage. In conclusion, ingesting 2 servings of beverage with 7.44 g dextrin fiber/serving did not significantly affect satiety and next meal energy intake in humans. The study was funded by The Coca‐Cola Company.
Effect of iron deficiency on serum lipids in rats
Authors: Yokoi Katsuhiko , Konomi Aki
Published: June 2021

Iron deficiency is known to cause dyslipidemia, although the serum lipid profile in simple iron deficiency is not well clarified. The aim of this study was to investigate the serum lipid profile in iron deficiency using a rat model. Twenty three‐week‐old male Fisher rats were divided to control and iron‐deficient groups and fed AIN‐93G diet and iron‐deficient diet, respectively, for 7 weeks. Blood was collected after overnight fast and serum was separated. Serum lipid profile and biochemical parameters were measured. Data were statistically compared by Welch's t test and P value less than 0.05 was considered significant. Blood hemoglobin and serum iron were markedly decreased in the iron‐deficient group compared with the control group. Compared with the control group, serum triglycerides, total cholesterol, free cholesterol and phospholipids of iron‐deficient group were significantly increased. Serum esterified cholesterol was almost identical between the groups. Compared to the control rats, both the percent HDL protein and the percent HDL cholesterol were significantly lower in serum of the iron‐deficient rats. Both the percent LDL protein and the VLDL protein were significantly higher in serum of the iron‐deficient rats than those of the control rats. The percent LDL/VLDL cholesterol was significantly higher in serum of the iron‐deficient rats than that of the control rats. These results suggest that iron deficiency induces dyslipidemia with increased LDL/VLDL and decreased HDL. Partly supported by the Iijima Memorial Foundation for the Promotion of Food Science and Technology.
High dietary iron and 137Cs radiation exposure induce oxidative stress and reduce bone mass
Authors: Yuen Evelyn , Morgan Jennifer L , Zwart Sara R , Gonzales Estela , Camp Kaleigh , Macias Brandon R , Smith Scott M , Bloomfield Susan A
Published: June 2021

Astronauts are exposed to increased iron (Fe) stores and risk radiation exposure during spaceflight. We hypothesized that a high Fe diet and radiation exposure would independently increase markers of oxidative stress and result in loss of bone mass. Male rats (3‐mo‐old, n=32) were randomized to receive an adequate (45 mg Fe/kg) or high (650 mg Fe/kg) Fe diet for 4 wks and either 3 Gy (8 fractions, 0.375 Gy each) of 137Cs radiation (γ RAD) or sham exposure starting on d 14. Ex vivo pQCT quantified volumetric bone mineral density (vBMD); bone mechanical strength (ultimate load, UL) was assessed by 3‐pt bending (midshaft tibia) and compression of the femoral neck. Serum Fe and catalase increased only with the combined treatment, whereas serum glutathione peroxidase decreased in all groups. γRAD and high Fe diet lowered proximal tibial (PT) cancellous vBMD (by −15% and − 12%, respectively); high Fe diet produced a small decrease in femoral neck (FN) total vBMD (−4%, p=0.07). Cortical vBMD at midshaft tibia was lower after high Fe diet, but not after γRAD. Higher serum Fe levels at 4 wks were associated with lower PT cancellous vBMD (r = −0.61); higher serum catalase was associated with lower vBMD at the 3 different bone sites (r = − 0.52). No significant differences in UL at mid‐shaft tibia or FN were detected. Oxidative stress is increased by fractionated γRAD and iron overload and is associated with a negative impact on bone mass.

Grant Funding Source : NASA Human Research Program and NSBRI via NASA NCC9‐588
Predictors of 5‐year change in plasma 25‐hydroxyvitamin D (25(OH)D) concentrations in postmenopausal women
Authors: Kluczynski Melissa , Platek Mary , DeNysschen Carol , Wactawski-Wende Jean , Millen Amy
Published: June 2021

Objective

Determine the predictors of 5‐year change in Δ 25(OH)D concentrations.

Methods

Postmenopausal women in the Osteoporosis and Periodontal Disease Study (N=668) had 25(OH)D assessments at baseline (1997–2000) and 5‐years (2002–2005). Baseline and Δ dietary, lifestyle and health‐related factors were tested as predictors using linear regression.

Results

The mean increase in 25(OH)D was 7.7 nmol/L (SD=0.7, P<0.001). Predictors explained 31% of the variance in Δ 25(OH)D and included baseline 25(OH)D, baseline and Δ vitamin D supplement intake and physical activity, Δ season of blood draw, Δ body mass index, Δ whole body T‐score, and baseline hormone use. Baseline 25(OH)D and Δ vitamin D supplement intake explained the most variance (25%) in 25(OH)D. In exploratory analyses, there was a borderline significant interaction between baseline 25(OH)D and Δ vitamin D supplement use after adjustment for predictors of Δ 25(OH)D (P=0.063). The greatest increase in 25(OH)D occurred in women in the lowest tertile of baseline 25(OH)D who increased supplement intake from baseline to follow‐up.

Conclusions

Baseline 25(OH)D and Δ vitamin D supplement intake were most predictive of increasing 25(OH)D. Increasing 25(OH)D through supplementation depends on initial 25(OH)D.
Effect of lipid extracts from edible blue‐green algae, Nostoc commune var. Sphaeroides Kützing and Spirulina Platensis, on the regulation of genes for cholesterol and lipid metabolism in HepG2 cells
Authors: Ku Chai Siah , Balunas Marcy J , Lee Jiyoung
Published: June 2021

We previously demonstrated that lipid extract (LE) from an edible blue‐green alga, Nostoc commune var. Sphaeroides Kützing (NO), inhibited the expression of genes involved in lipogenesis, cholesterol synthesis and LDL uptake by repressing maturation of sterol regulatory element binding protein 1 (SREBP‐1) and SREBP‐2 in HepG2 cells. To compare the effect of NO with Spirulina Platensis (SP), the most common BGA for human consumption, LE was prepared with dichloromethane/methanol (2:1) from two blue‐green algae species and HepG2 cells were incubated with the algal LE for 24 hr. Both algal LE decreased mRNA levels of LDL receptor (LDLR), HMG‐CoA reductase (HMGR) and SREBP‐2 in a dose‐dependent manner (0–100 g/ml). Protein levels of the genes were also diminished by algal LE except mature SREBP‐2 protein in NO LE‐treated cells. Fatty acid synthase (FAS) and stearoyl CoA desaturase mRNA as well as FAS protein levels were significantly lowered by NO and SP LE with concomitant decreases in SREBP‐1c mRNA and its mature protein. The results suggest NO and SP LE contain bioactive components that inhibit SREBP‐1c expression and maturation to repress lipogenic gene expression; and different mechanism may mediate the repressive effect of NO and SP LE on the expression of LDLR and HMGR because mature SREBP‐2 protein was not diminished by NO LE whereas SP LE markedly reduced the protein levels

Grant Funding Source: NIH R21AT005152
Polymethoxyflavones and Atorvastatin Synergistically Inhibits Breast Cancer Cell Growth
Authors: li longfang , Charoensinphon Noppawat , Zheng Jinkai , Xiao Hang
Published: June 2021

Utilization of potential synergistic interactions among different bioactive agents is a promising approach to inhibit complex diseases such as cancer. Nobiletin (NBT) and tangeretin (TAN) are major polymethoxyflavones found in citrus fruits. Herein, we studied NBT and TAN in combination with atorvastatin (ATST, Lipitor, a cholesterol‐lowering drug) in MDAMB231 and MCF‐7 human breast cancer cells. Both NBT/ATST and TAN/ATST combinations at low doses produced much stronger inhibitory effect on cancer cell viability in comparison to those produced by NBT, TAN or ATST alone at much higher doses. Isobologram analysis confirmed that both NBT/ATST and TAN/ATST combinations produced strong synergy in inhibiting the growth of two breast cancer cell lines. Flow cytometry analysis showed that both NBT/ATST and TAN/ATST combinations caused significant cell cycle arrest at G0/G1 phase in both MDAMB231 and MCF‐7 cells after 48 hrs of treatments. Consistent with these results, NBT/ATST and TAN/ATST combinations decreased expression levels of Akt, cyclin D1, and CDK4, while increased expression levels of p21, PTEN, and phosphorylated PTEN (Ser380). In conclusion, our result demonstrated strong synergy between two major citrus polymethoxyflavones and ATST in inhibiting human breast cancer cell growth.

Grant Funding Source : NIH:CA139174, AICR:#10A044
Eicosapentaenoic acid enhances nitric oxide production through up‐regulating SIRT1 expression in human endothelial cells
Authors: Fukuo Keisuke , Fukada Rumi
Published: June 2021

Accumulating evidence indicates that eicosapentaenoic acid (EPA), a polyunsaturated fatty acid of the n‐3 series extracted from fish oils, has anti‐atherogenic effects. However, the molecular mechanism of these beneficial effects remains unclear. Here, we show that EPA enhances nitric oxide (NO) production from human umbilical endothelial cells (HUVEC) which was determined by a fluorescent indicator DAF‐2. EPA also suppressed an increase in SA‐β‐gal positive cells induced by NG, NG‐dimethylarginine dihydrochloride (ADMA), a NO synthase inhibitor. siRNA‐mediated SIRT1 gene silencing cancelled EPA‐induced suppression of premature senescence and enhancement of NO production in these cells. These results suggest that up‐regulation of SIRT1 expression in endothelial cells may participate in the mechanism underlying the beneficial effects induced by EPA.