bluuebunny/crossref_metadata_2025 huggingface dataset:
Carbamylated LDL: the missing link between uremia and atherosclerosis
Authors: Basnakian Alexei G. , Apostolov Eugene O. , Shah Sudhir V.
Published: June 2021

Cardiovascular disease (CVD) due to atherosclerosis is an independent risk factor and the leading cause of death in uremic patients with chronic renal failure (CRF). Based on in vitro studies, carbamylated low‐density lipoprotein (cLDL), a product of LDL modification by urea‐derived cianate previously known as “uremic LDL,” has been recently recognized as a potential atherogenic factor induced by uremia. In this study, to determine the role of cLDL in atherogenesis in vivo, we used ApoE knockout mice fed with a high‐fat diet to induce elevation of LDL in blood plasma, while stable increase of plasma urea was achieved by surgically inducing CRF or increasing urea consumption supplied with drinking water. Our results showed that in both models, only mice on high‐fat diet with increased urea had elevated plasma cLDL, whereas oxidized LDL (oxLDL) remained unchanged. The cLDL increase was associated with aggravated atherosclerosis measured by intravital ultrasound echography and en face staining of lipid deposits in aorta, and cLDL was localized in the aortic wall. In a pilot study, CRF patients on hemodialysis were shown to have normal oxLDL and elevated cLDL that correlated with carotid atherosclerosis. This study is the first to demonstrate the role of cLDL in uremia‐induced atherosclerosis in vivo. The study was supported by NIH/NHLBI grant to A.G.B, and AHA grant to E.O.A.
Indigenous microbiota influence epithelial homeostasis through the activation of Reactive Oxygen Species
Authors: Jones Rheinallt , Luo Liping , Neish Andrew
Published: June 2021

There is increasing recognition of the roles played by enteric bacteria in the biology of metazoan hosts. For example, the microbiota influences epithelial barrier function, immune modulation and cell proliferation. Recently, multiple lines of investigation have shown that the rapid, physiological generation of reactive oxygen species (ROS) is a cardinal response in all metazoans to bacterial stimuli. Using axenic Drosophila, we demonstrate that ROS is rapidly induced in the fly midgut 30 minutes following conventionalization with commensal bacteria, followed by activation of the CncC/Nrf2 signaling pathway, transcriptional activation of CncC/Nrf‐2 responsive genes, and increase in the ratio of oxidized GSH:GSSH. Functionally, ROS stimulated by microbiota in the gut is known to stimulate stem cell proliferation. Consistently, CncC/Nrf‐2 loss of function mutants exhibit reduced stem cell proliferation when conventionalized with natural Drosophila flora. Furthermore, microbially induced ROS production is elevated anterior to the fly hindgut proliferation zone (HPZ), a region functionally analogous to mammalian intestinal crypts, suggesting that the CncC/Nrf2 xenobiotic response pathway is involved in gene regulatory events necessary for normal gut development and homeostasis.
Medical students using plastinated prosections as a sole learning tool perform equally well on identification exams as compared to those performing dissections over the same regions
Authors: Hoffmann Darren S , May Nikolas , Thomsen Timothy , Holec Megan , Andersen Kathleen H , Pizzimenti Marc A
Published: June 2021

We sought to determine if small plastinated specimens would be sufficient to replace traditional dissection/prosection methods. A small group of pre‐M1 students (n=26) participated in labs and learned from dissection (D), or plastinated prosections (PP) of body regions/organs. Students who learned the heart from PP performed slightly better on the final identification exam than those who dissected the heart (67.0±6.2 PP vs. 60.3±8.6 D). The exam consisted of tags on both PP and non‐plastinated (NP) hearts. The difference between the groups was due to higher scores from PP students on NP heart tags (70.0±7.2 PP vs. 54.8±8.3 NP). Both groups performed equally on PP heart tags. Other control regions where both groups used the same learning modality had identical scores between groups. To assess differences in learning from PP vs. NP prosections, groups studied the axilla from PP or NP prosections. Students using PP slightly outperformed those learning from traditional NP prosections (51.1±7.9 PP vs. 43.0±6.8 NP). Interestingly, when asked to rank usefulness of the modalities (1–5 Likert scale), students ranked PP significantly lower than D or NP (3.36±0.4 PP vs. 4.36±0.2 NP and 4.46±0.4 D, p<0.05). Reasons ranged from physical properties of the stiffer plastinates to changes in engagement level. These data support use of PP in the medical‐level anatomy curriculum, but student response data indicate limitations.

Grant Funding Source: University of Iowa OCRME
A functional proteomics approach to understanding the PI3K‐insulin signaling network in fat cells
Authors: Teruel Mary N.
Published: June 2021

The insulin‐PI3K signaling network controls many important outputs of fat cells such as glucose uptake, lipogenesis, and differentiation from preadipocytes into adipocytes, and these processes happen on very different timescales from minutes to days. The molecular mechanisms and timing principles that explain how specific functional outputs are generated in these cells is not well understood. Because of the critical role PIP3 plays in these processes, we first sought to understand how many proteins could be regulated by PIP3 by using a live‐cell imaging and bioinformatics approach [1]. We identified ~40 proteins, and we are now using fat cell lines, automated high‐throughput single cell imaging techniques, self‐made libraries of siRNA, and targeted selective reaction monitoring (SRM) mass spectrometry in order to assess the roles of these candidate genes in this important signaling network. Findings from our studies are expected to lead to new mechanistic insights into diseases such as diabetes, obesity, cardiovascular disease, and other fat and insulin‐related disorders.
Iron repletion at postnatal day 8 does not correct monoamine metabolism in early iron deficient rats
Authors: Wilkinson Amanda Lin , Beard John , Bianco Laura , Felt Barbara , Unger Erica
Published: June 2021

Iron deficiency in utero and in early postnatal life causes changes in brain development and associated behaviors that can extend into the individual's second decade of life. Rodent models have shown that alterations in brain monoamine metabolism due to dietary iron deficiency in early life appear to be associated with changes in neurobehavioral development. Based on earlier studies, the ideal time for iron repletion in the rat appears to be after day 4 (P4) of postnatal life and sometime before P15. In this study, rats were subjected to one of three treatments: 1) iron sufficient through gestation and lactation; 2) iron deficient beginning on G5; 3) iron deficient beginning on G5 followed by iron sufficient at P8. Although regional brain iron levels in iron repleted rats were similar to control by P21, dopamine and other monoamine levels were significantly reduced in prefrontal cortex and ventral midbrain at P21 and P90 and in striatum at P90. Monoamine‐related protein levels were also disturbed in the iron supplemented group at both time points. These results suggest that iron repletion at P8 is too late to normalize changes in brain monoamine neurotransmission caused by early life iron deficiency. Supported by NIH grant PO1‐HD39386.
Effects of theobromine, a caffeine‐like substance found in cocoa and chocolate, on mood and vigilance
Authors: Judelson Daniel A , Griel Amy E , Miller Debra , Muñoz Colleen X , Kellogg Mark D , Lieberman Harris R
Published: June 2021

Like caffeine (CAF), theobromine (ThBr) is a methylxanthine found in foods such as cocoa and chocolate that might influence mood. ThBr crosses the blood‐brain barrier and binds to adenosine receptors, suggesting it might share CAF's beneficial effects on mood and vigilance. Therefore, we assessed the effect of ThBr doses commonly found in foods on mood and vigilance parameters sensitive to CAF. CAF was tested as a positive control. Twenty‐four males (age = 23 ± 3 y) completed six double‐blind trials during which they consumed experimental beverages, completed self‐report mood questionnaires, and completed a two hour visual vigilance task. Three experimental beverages (100 mg, 200 mg, and 400 mg ThBr) used a cocoa vehicle; three matched control beverages (0 mg ThBr, 400 mg ThBr, and 100 mg CAF) used a non‐cocoa carrier. Mean salivary [ThBr] exhibited appropriate dose‐dependent differences (400 mg trials > 200 mg trial > 100 mg trial > 0 mg trials, p < 0.05). At every dose tested, ThBr failed to consistently affect mood state or vigilance, but 100 mg CAF expectedly decreased lethargy/fatigue and increased vigor (p < 0.05). These findings indicate ThBr does not influence mood and vigilance when administered in nutritionally‐relevant doses, despite sharing many of CAF's characteristics. Further research is needed to better understand the behavioral effects of cocoa and dark chocolate.

Funded by The Hershey Company.
Synergy®, a prebiotic, but not genistein supplementation, either alone or with Synergy®, affects bone mechanical properties in ovariectomized rats
Authors: Legette LeeCole L , Martin Berdine R , Barnes Stephen , Weaver Connie M
Published: June 2021

Osteoporosis primarily occurs among postmenopausal women, due to age deficiencies in calcium metabolism as well as estrogen‐related bone loss. Prebiotics and phytoestrogens can enhance calcium metabolism and inhibit post‐menopausal bone loss. Recent evidence suggests a combination of prebiotics and phytoestrogen consumption results in greater effects on bone health. A four week feeding study was conducted in 5 mo. old ovariectomized (OVX) Sprague Dawley rats to examine the effect of genistein and genistein + Synergy® (prebiotic) on calcium metabolism and bone health. There were six treatment groups (n=16/group): SHAM Control, OVX Control, OVX rats receiving daily estradiol injections, and OVX rats receiving an AIN 93M diet supplement with either 200 ppm genistein, 5% Synergy®, or 200 ppm genistein + 5% Synergy®. SHAM Control rats had significantly higher femoral bone density, as determined by underwater weighing, than all other OVX groups. A three‐point bending test showed increased bone breaking force (p<0.05) for SHAM Control, OVX rats receiving daily estradiol injections, and OVX rats on 5% Synergy® diet compared to other OVX groups. We conclude that prebiotic (Synergy®) supplementation but not phytoestrogen (genistein) improves bone biomechanical strength in ovariectomized rats.

Grant Funding Source: General Mills
Permeability of rosmarinic acid from Prunella vulgaris and ursolic acid from sage extract across Caco‐2 cells
Authors: Qiang Zhiyi , Ye Zhong , Etsitty Nathan , Hauck Cathy , Murphy Patricia , Reddy Manju , Hendrich Suzanne
Published: June 2021

We hypothesized that rosmarinic and ursolic acids would show similar permeability in Caco‐2 cells as pure compounds or from plant extracts (Prunella vulgaris and sage (Salvia officinalis)). The percentages of rosmarinic acid (RA) and ursolic acid (UA) in three ethanol extracts of P. vulgaris were 4.8±0.3 − 17.0 ±0.9% and 0.05±0.01 – 0.50±0.09%. Sage extract contained 26.0±4.0% UA. Concentrations ≥ 50 μM of pure RA and Prunella extracts containing ≥ 20 μM RA showed significant cytotoxicity to Caco‐2 cells whereas concentrations ≥ 20 μM of pure UA and sage extract were toxic to the Caco‐2 cells, measured by MTS assay. After incubation with β‐glucuronidase/sulfatase, 10.5±0.3% and 10.7±0.4 % of applied amounts of pure RA or RA from P. vulgaris extract were found in the cells. UA passed through the basolateral membrane without significant glucuronidation or sulfation. Apparent permeability of pure UA and UA from sage extract (5, 10 and 20 μM) was 3.5±0.8 cm/s. Extract matrix did not affect permeability of either compound. Apical recoveries of pure RA or RA from P. vulgaris were 81.5±4.6 – 93.7±9.3%. No RA was found basolaterally at transepithelial electrical resistance (TER) ≥ 250 Ωcm2. But 5.0±1.6% and 7.5±1.0% of 10 μM RA were recovered basolaterally at TERs of 150±10 and 210±10 Ωcm2. Modeling in vivo paracellular transfer in Caco‐2 cells may need TER < 250 Ωcm2. Supported by 95P50AT004155 NCCAM and ODS, NIH.
Anthocyanins in brain regions after long‐term blueberry feeding
Authors: Milbury Paul E. , Kalt Wilhelmina
Published: June 2021

Xenobiotic metabolism involves ancient and well conserved pathways that cause biotransformation and removal of foreign compounds taken in by an organism. Anthocyanins are quickly removed from the body via xenobiotic metabolism. Nevertheless, evidence suggests these polyphenolic compounds may protect neurological tissues by reducing neuroinflammation, decreasing age‐related neurodegenerative disorders, and cognitive decline. Research of the past decades demonstrates that anthocyanins are potent modulators of cell signal transduction and are capable of altering hundreds of metabolic pathways in mammalian cells. Anthocyanins are bioavailability to the circulation; however, less is known about their bioavailability to brain tissue. Understanding anthocyanins and/or anthocyanin metabolite bioavailability to the brain is critical to ascertain their plausible bioactivity. Here we report levels of anthocyanins found in cortex, cerebellum, and midbrain & diencephalon at 18 hours postprandial in pigs fed 2% whole freeze dried blueberries in the diet for 8 weeks. Anthocyanins were found in the femptomole/gram FW tissue range with glucuronides at 1/10th the levels of parent anthocyanins. At these levels plausible mechanism of neuroprotective action of anthocyanins are more likely via modulation of signal transduction processes and/or gene expression rather than by direct radical quenching.
Thinking out of the box: Using the transplantation procedure to teach renal anatomy
Authors: Lerner Susan Michelle , Palese Michael , Reidenberg Joy S , Laitman Jeffrey
Published: June 2021

An aim of our anatomy curriculum is to challenge the current conceptual framework within which anatomy is usually taught and use innovative ways to introduce clinical thinking. A renal transplant module was created with the assistance of a transplant surgeon and a urologist. The module was implemented during a three hour laboratory devoted to retroperitoneal dissection. The module consisted of two parts: laparoscopic donor nephrectomy procedure, and open renal procurement and subsequent transplantation. The laparoscopic procedure utilized two intact cadavers, and the urologist supplied the laparoscopic equipment. Every student participated in a guided laparoscopic dissection of the kidney. Meanwhile, the transplant surgeon assisted the students in dissecting a kidney on their own cadaver, guiding them in how to preserve renal vasculature and ureter. An extraperitoneal space was then created in the pelvis so that the iliac vessels and bladder were identified. The kidney was then “transplanted.” This combined experience allowed every student to physically perform a transplant. Integrating anatomy with surgical procedures and new visualization technologies not only increases learning, but also fosters an appreciation of the team approach to education. We hope to expand this use of surgical procedures to integrate clinically relevant content and facilitate the understanding of human anatomy.
Gross anatomy as the foundation of integrated veterinary biomedical curriculum
Authors: Singh Baljit
Published: June 2021

The curriculum reform is usually accompanied by reduced times allocated to the teaching of anatomy. During the recent review and revision of the veterinary medical curriculum at the University of Saskatchewan, we successfully pursued the argument to integrate the teaching of veterinary biomedical disciplines around the teaching of gross anatomy. The dissection of dog in a regional format is used to teach the comparative anatomy of other veterinary species, and to coordinate and integrate the teaching of histology, embryology, biochemistry and physiology. At the end of teaching of a particular region, we do integrative clinical case studies in groups of 7–8 students (3 sessions of 90 minutes each) to integrate the information from anatomy, physiology and biochemistry. At the end each case study, the whole class is brought together for a wrap‐up session. In addition to better disciplinary and professional skills learning outcomes for the students, there is better cohesion among the biomedical science faculty. Because many colleagues from clinical departments help in development and facilitation of the integrative case studies, there is better interaction and communication between the departments.
Nothing in the Biology of Glycans Makes Sense, Except in the Light of Evolution
Authors: Varki Ajit
Published: June 2021

All cells in nature display cell surface glycans that are involved in host biological processes, and provide pathogen binding sites. Thus, glycans are trapped in evolutionary “Red Queen” effects, with long‐lived hosts evading their more rapidly evolving pathogens by changing glycan expression, without compromising intrinsic function. This helps explain glycan structural variations in nature, which contributes to biological diversity. Sometimes, one glycan type is eliminated in an evolutionary lineage, e.g., human‐specific loss of the sialic acid Neu5Gc, which affects pathogen recognition. Many human pathogens also disguise themselves with human‐like sialic acids (molecular mimicry) by convergent evolution, thus co‐opting host Siglecs normally dedicated to recognizing self. Such differences between humans and great apes involving sialic acids have implications for unusual features of human immunity. Also, incorporation of Neu5Gc into humans occurs from food, and a similar process contaminates biotherapeutic molecules and cells. As all humans have complement‐fixing anti‐Neu5Gc antibodies, this may contribute to some diseases, and reactions to biotherapeutic products. Finally, we hypothesize that such antibodies restrict transmission of enveloped viruses, and could change fertility, allowing sympatric speciation (collaboration with Pascal Gagneux).
Regulation of sympathetic and enteric nervous system development by Hand2
Authors: Cserjesi Peter , Maska Emily , Hua Lisa , Gershon Michael D , Morikawa Yuka
Published: June 2021

The sympathetic nervous system (SNS) and enteric nervous system (ENS) employ many of the same signaling pathways and transcription circuits to regulate their development. However, while the SNS is a relatively simple nervous system, with neurons predominantly noradrenergic, the ENS is composed of neurons that are as diverse as those found in the central nervous system. This suggests that molecules regulating development of these two nervous systems function in both unique and in overlapping roles. The Hand2 basic helix‐loop‐helix transcription factor is expressed in both the SNS and ENS during development and our analysis of Hand2 function in mice shows that it regulates similar and unique events during their development. In the SNS, Hand2 is required for proliferation, survival and noradrenergic differentiation of neurons. Analysis of the transcriptional circuit regulating catecholaminergic differentiation showed that it does not affect expression of GATA3. Phox2a or Phox2b suggesting that it may directly regulate genes encoding the norepinephrine biosynthetic enzymes. In the ENS, loss of Hand2 leads to changes in the ratios of neurons expressing different neuronal transmitters and in ENS patterning. We will present a comparative analysis of how Hand2 regulates different aspects of SNS and ENS development.
Morphological adaptations in the brain motive circuit induced by 3,4‐methylenedioxymethamphetamine (MDMA; ecstasy)
Authors: Ball Kevin
Published: June 2021

MDMA is a widely used amphetamine derivative that increases dopamine and serotonin transmission via its interaction with monoamine transporters. Compared to other psychostimulants, little is known about the long‐term neurobehavioral effects of MDMA. We conducted a series of studies aimed at elucidating the effects of MDMA administration on behavior, limbic cortico‐striatal neuronal structure, and striatal electrophysiology. We found that repeated MDMA administration induces long‐lasting changes in behavior that are related to altered striatal neuronal activity and limbic cortico‐striatal morphology. Also, we found that the neurobehavioral effects of MDMA are strongly modulated by individual differences and the context surrounding drug administration. These results provide unique insight into the neural mechanisms underlying the behavioral effects of MDMA and perhaps the substrates of maladaptive drug use in general.
Signaling Lessons from Death Receptors
Authors: Dixit Vishva M.
Published: June 2021

It was thought that receptors signaled either by serving as ion channels or by altering phosphorylation‐dephosphorylation events. Work in my laboratory in the mid‐nineties conclusively showed that death domain‐containing receptors signaled by an entirely new mechanism, specifically, adapter (FADD)‐mediated recruitment and direct activation of a death protease (FLICE/caspase‐8). Subsequent studies by my own and other laboratories showed that this was a universal mechanism deployed by death receptors.

Further study of the NF‐kB inducing death receptor, TNFR1, has recently unveiled another new signaling mechanism, that we have termed “ubiquitin editing.” Ubiquitin editing is mediated by a highly conserved single polypeptide protein, termed A20, which contains both a ubiquitin hydrolase and a ubiquitin ligase domain. Initially, this seemed counterintuitive as it was akin to a molecule possessing both kinase and phosphatase activities –– the ultimate futile cycle! We found, however, that these seemingly contradictory activities actually act in concert to attenuate cytokine signaling.
The engineering of developmental regulation
Authors: Lander Arthur D
Published: June 2021

It is fast becoming clear that, to understand the complexity of biological systems, it is not enough just to have mechanistic explanations for how things happen. We also need explanations for why things are there, i.e. what it is about particular states of affairs that enabled them to have been selected for. Among Systems Biologists, it is often asserted that “strategic” goals—things like robustness, speed, noise‐filtering, flexibility, adaptability, etc.—are likely to be the major drivers of complexity, more so than, say, physical constraints or “frozen accidents” of evolution. Animal development provides a wonderful context in which to explore this idea, because a wealth of experimental research has revealed the existence of bewilderingly complex, yet extremely highly conserved, networks of gene‐ and cell‐cell regulation. I will focus on two broad areas—morphogen‐mediated pattern formation and intrinsic tissue growth control—in which exploratory modeling, together with targeted experimentation, gives plausible glimpses of underlying “design principles”. I will discuss concrete examples in which the need to meet multiple performance objectives seems to justify complicated regulatory architectures.
Systematic review of the effect of dietary linoleic acid on changes of tissue levels of arachidonic acid and docosahexaenoic acid in humans
Authors: Rett Brian , Whelan Jay
Published: June 2021

Linoleic acid (LA), with a DRI of 11–17g/d, is the most commonly consumed polyunsaturated fatty acid (PUFA) in the Western diet. The concern is that LA is the metabolic precursor of arachidonic acid (AA) and its consumption may enrich tissues with AA and contribute to chronic and overproduction of bioactive eicosanoids derived from AA. Similarly, there is a concern that dietary LA may interfere with the production and incorporation of the long chain n‐3 PUFA into tissues, in particular, docosahexaenoic acid (DHA). However, no systematic review of human trials regarding LA consumption and subsequent changes in tissue levels of AA or DHA has been undertaken. In this study, we systematically reviewed the human literature that reported changes in dietary LA and its subsequent impact on changing tissue AA and/or DHA in platelets, erythrocytes and plasma phospholipids. Decreasing dietary LA up to 90% failed to modify tissue AA levels (p=0.39). When dietary LA levels were increased 6 fold, no changes in tissue AA levels were observed (p=0.72). Similarly, decreasing (by 90%) or increasing (6 fold) dietary LA failed to modify tissue DHA levels (p=0.39 and p=0.55, respectively). Our results suggest that modifying current intakes of dietary LA have no effect on changing tissue levels of AA or DHA in adults. (Supported, in part, by the TN AES and in conjunction with USDA's NC‐1039 multistate research project).
Dairy intake not associated with metabolic syndrome but milk and yogurt intake is inversely associated with prevalence of hypertension in middle‐aged adults
Authors: Troy Lisa M. , Jacques Paul F. , Vasan Ramachandran S. , McKeown Nicola M.
Published: June 2021

This study examined cross‐sectional associations of dairy intakes and prevalence of metabolic syndrome (MS) and the individual components of MS among 3104 participants in the Framingham Offspring Study. To be consistent with the Dietary Guidelines for Americans, dairy intakes were converted from servings per day to cup equivalents (c). We used logistic regression to calculate odds ratios (OR) between the lowest (< 0.4 c/d) compared to the highest (>3.0 c/d) quintile of diary intakes. After adjustment for age, sex, smoking, total energy and alcohol intakes, dairy intakes (OR= 0.78, (95% CI 0.60, 0.99)), as well as milk and yogurt intakes (OR=0.75 (0.58, 0.97)), were inversely associated with MS. These results were attenuated and no longer significant after adjustment for other aspects of a healthy dietary pattern (whole grain, fruit and vegetable intakes). With respect to the individual components of MS, an inverse association was observed with only milk and yogurt intakes and prevalence of hypertension (OR= 0.76, (0.57, 0.98)). This association remained significant after adjustment for aspects of a healthy dietary pattern and supplemental calcium. Although dairy intakes do not appear to be independently associated with MS, higher milk and yogurt intakes were inversely associated with prevalence of hypertension in middle aged adults. Support from General Mills, USDA (58‐1950‐7‐707), NHLBI (N01‐HC‐25195).
Induction of PCK1 Expression by Palmitate in HepG2 Cells: Involvement of Multiple Pathways
Authors: Mamedova Laman K , Bradford Barry J
Published: June 2021

Type 2 diabetes is associated with enhanced gluconeogenesis. Saturated fatty acids alter hepatic metabolism, and at least 3 inflammatory pathways are proposed to mediate such effects. Fatty acids may act by 1) binding and activating Toll‐like receptor 4 (TLR4), 2) causing oxidative stress, and/or 3) promoting synthesis of lipids such as diacylglycerols (DAG) and ceramides (CER). We tested the roles of these pathways in mediating palmitate effects on expression of PCK1, a rate‐controlling gluconeogenic enzyme. HepG2 cells were incubated in DMEM ± 1 mM palmitate for 24 h. Specific pathways were blocked with a peptide antagonist of TLR4 (1 μM), myriocin (1 μM; CER synthesis inhibitor), or vitamin E (50 μM; antioxidant). Treatment effects were declared at P < 0.05. No treatments affected cell viability at 24 h. Palmitate increased PCK1 mRNA by 4‐fold. Myriocin and vitamin E prevented the induction of PCK1 by palmitate, and the TLR4 antagonist decreased PCK1 abundance with or without palmitate. Palmitate induced a 3.6‐fold increase in cellular DAG, but did not alter CER content. All pathway blockades decreased CER content, especially without palmitate. In contrast, only myriocin and vitamin E decreased DAG content, and only in palmitate‐treated cells. Results demonstrated that inhibiting any one of these pathways was sufficient to prevent the induction of PCK1 expression, and multiple pathways also altered CER and DAG content.
Vitamin D2 enriched mushrooms stimulate innate immunity in LPS challenged rats
Authors: Babu Uma Suresh , Garthoff Larry H. , Calvo Mona S.
Published: June 2021

Vitamin D (vit D) functions in both innate and acquired immunity. The high prevalence of poor vit D status is due in part to limited intake of naturally rich or vit D‐fortified foods. We exposed white button edible mushrooms to UVB light to markedly increase vit D2 content, creating a naturally rich food source. Our goal was to determine whether the higher vit D2 content of UVB exposed edible mushrooms is bioavailable and functional in modulating innate immune response in rats acutely challenged with lipopolysaccharide (LPS). For 10 wk, 300 weanling female rats were fed 1 of 5 diets, all formulated based on AIN93G to contain: 1) control levels of vit D; 2) no vit D; 3) no vit D +5% unexposed mushroom; 4) no vit D +2.5% UVB exposed mushroom, and 5) no vit D +5% UVB exposed mushroom (Research Diets, New Brunswick, NJ). After vit D analyses, dry powdered mushroom was added at the expense of non‐nutritive fiber. At wk 10, rats were challenged with either saline (control) or LPS and necropsies were performed at 3, 24 and 72 hrs when spleen cells were evaluated for alterations in natural killer cell activity (NK). NK activity was assessed by the standard 51Cr release assay using YAC‐1 cells as target cells and rat splenocytes as the effector cells (1:100 ratio). Independent of the saline or LPS challenge, the NK activity was higher in rats fed the highest level (5%) of vit D enhanced mushrooms when compared to the control fed or vit D deficient diets with 5% unexposed or no mushroom.

Conclusions

Vitamin D2 from UVB exposed white button mushrooms is bioavailable and effectively functions in innate immunity to stimulate NK activity in a rat model. Source of research support: The Mushroom Council and FDA
Galacto‐Oligosaccharides Modulate Gastrointestinal and Systemic Lymphocyte Populations of SMAD3 Knockout Mice
Authors: Duriancik David M , Clinthorne Jonathan F , Gopalakrishnan Anita , Fenton Jenifer I , Gardner Elizabeth M
Published: June 2021

Galacto‐oligosaccharides (GOS) are prebiotics that support the growth of bifidobacteria and lactobacilli. During influenza vaccination, mice supplemented with GOS had increased T helper (Th) 1 delayed‐type hypersensitivity biomarkers. The objective of our study was to determine the effects of GOS on gastrointestinal and systemic immune cell populations. We hypothesized that GOS would support Th1 responses by increasing CD8+ T cell and Natural Killer (NK) cell numbers. We gavaged 129/Sv SMAD3 knockout mice with 5,000mg GOS/Kg body weight/day for 7 and 14 days and excised blood, spleen, mesenteric lymph nodes (mLN), and Peyer's patches (PPs). Lymphocytes were isolated and stained for flow cytometric analysis of Th cells (CD3+/CD4+), cytotoxic T cells (CD3+/CD8+), B cells (CD19+), and immature (NKp46+/DX5−) and mature NK cells (NKp46+/DX5+). GOS treatment increased total CD4+ T cells in the PPs and mLN within 1 week. GOS also increased CD8+ cytotoxic T lymphocytes in PPs by 1 week and blood by 2 weeks. Mature NK cells were increased in the blood after 2 weeks of GOS treatment. Therefore, GOS treatment modulates both gastrointestinal and systemic immune cell populations. The immune response is Th1 biased during steady‐state conditions in SMAD3 knockout mice treated with GOS. Therefore, GOS may be useful prophylactics and therapeutics. This study was generously supported by GTC Nutritionals.
Cinnamon extract increases tristetraprolin and decreases vascular endothelial growth factor gene expression in mouse adipocytes
Authors: Cao Heping , Anderson Richard
Published: June 2021

Cinnamon is proposed to improve the metabolic syndrome due to its insulin‐like activity (Khan et al., 2003, Diabetes, 26:3215–8; Cao et al., 2008, AgroFood Industry Hi‐tech, 19:14–17). Insulin increases tristetraprolin (TTP, a RNA binding and destabilizing protein) and decreases vascular endothelial growth factor (VEGF, a proangiogenic cytokine) gene expression in cultured adipocytes (Cao et al., 2008, Obesity, 16:1208–18). This study tested the hypothesis that CE has insulin‐like and insulin‐independent effects on the regulation of TTP, VEGF, and related gene expression in cultured adipocytes. Quantitative real‐time PCR was used to estimate mRNA levels in mouse 3T3‐L1 adipocytes. CE (100 μg/ml), like insulin, increased TTP mRNA levels by several‐fold in the adipocytes, but unlike insulin, its stimulation on TTP expression sustained over a much longer time. The levels of VEGF mRNA, a putative target of TTP, were decreased approximately 50% by CE. CE also affected the expression of a number of other genes in the adipocytes. This study demonstrates that CE has insulin‐like effects including rapid induction of TTP mRNA and reduction of VEGF mRNA, and that CE has insulin‐independent effects on sustained increases in TTP expression (Supported in part by USDA‐ARS Human Nutrition and Quality and Utilization of Agricultural Products Research Programs).
Reduced weight gain and improved insulin sensitivity in high‐fat fed mice by treatment with a mixture of a reduced isohumulones from hops and an extract from acacia
Authors: Tripp Matthew L , Vroegrijk Irene , van Diepen Janna A , Darland Gary , Konda Veera R , Bland Jeffrey S , Voshol Peter J
Published: June 2021

Bioactive natural products obtained from foods may be safely incorporated into a lifestyle program and help mitigate metabolic disturbances caused by a westernized high fat diet. Previously we screened 200+ botanicals and discovered that a mixture of an extract of Acacia nilotica (ANE) and reduced iso‐alpha acids (RHO) from Humulus lupulus increased insulin sensitivity in a 3T3‐L1 adipocyte model of lipogenesis. Subsequent studies in db/db mice established that META352, a 5:1 mixture of RHO:ANE, was optimal for reducing fasting insulin and glucose. We evaluated META352 in a model of high fat diet (HFD) induced obesity in which C57BL mice were maintained on a diet that included 45% lard for 12 weeks. HFD fed mice supplemented with META352 (100 mg/kg body weight) exhibited a significant reduction in weight gain (~20%); subcutaneous and gonadal fat were reduced by 50% and fasting glucose and insulin were reduced by 25% and 80%, respectively (p<0.05). Oral glucose tolerance test and insulin sensitivity test showed that META352 improved insulin sensitivity in the META352 supplemented mice (p<0.05) compared to the HFD fed mice. In conclusion, META352, a proprietary combination of RHO and ANE, reduced elevated plasma insulin and glucose in the db/db mice, reduced weight gain, body fat, and improved insulin sensitivity in high‐fat fed mice.

Supported by MetaProteomics, LLC.
Effects of defatted soy bean on weight reduction in C57BL/6 mice
Authors: Lee Ji Hye , Park Hyo‐Min , Do Kyung‐Rok , Lee Sung‐Joon
Published: June 2021

Soy bean, which contains high levels of dietary fibers and phytochemicals, has been suggested for its anti‐obesity functions; however, the mechanism has been elusive. We examined the effect of defatted soy bean (DFSB) on body weight reduction in male C57BL/6 mice. Mice were fed control (AIN‐76) or DFSB diet (20% of casein was replaced with DFSB) for 10 weeks. After the feeding, control group showed increased body weight (+13.0±0.7g), while the body weight in DFSB group was only marginally changed (+2.0±1.0g). In blood analysis, DFSB group tended to have lower plasma concentrations of glucose (−32%), total cholesterol (−24%), and triacylglycerol (−4%) compared with controls. HDL/LDL ratio was higher in DFSB group compared with controls (11.1 vs 7.1, respectively). Results from oral glucose tolerance test showed improved glucose tolerance in DFSB groups assessed with the area under curve. In addition, average adipose tissue size and weights were significantly decreased in DFSB group. Interestingly, PPAR‐δ expression in adipocytes was dramatically up‐regulated up to 3.95‐fold compared with control (P<0.005). Accordingly, plasma levels of insulin and leptin were both significantly lowered in DFSB group compared with controls (−78% and −18%, respectively). These suggest that DFSB may reduce body fat contents and adipocyte size with activation of PPAR‐δ expression and reduced leptin concentration.
Effect of a Novel Eicosapentaenoic Acid‐Rich Oil on Serum Cholesterol in Man: Comparison to Docosahexaenoic Acid
Authors: Gillies Peter , Asztalos Ivor , Gleason Joi , Horvath Katalin , Dansinger Michael , Schaefer Ernst
Published: June 2021

Background

Fish oil and DHA raise LDL cholesterol (LDL‐C); the effects of EPA are less defined.

Study Design

121 healthy volunteers were recruited into a randomized, double‐blinded, placebo‐controlled, parallel‐arm, 6 week study. The placebo group received olive oil; the low dose EPA group (EPA600) received 600 mg/day of a yeast derived EPA; the high dose EPA group (EPA1800) received 1800 mg/day, and the DHA group (DHA600) received 600 mg/day of an algal derived DHA. Notably, the EPA oil did not contain any DHA and the DHA oil did not contain any EPA.

Results

110 subjects completed the study. The study population was 21–70 yrs of age, 67% male, 33% female, with an average BMI of 27.4. Subjects were not allowed lipid‐lowering medications or omega‐3 dietary supplements during the study and were counseled to maintain their normal diet and exercise programs. The number of subjects who remained free of fishy aftertaste or eructation was 92% for placebo, 85% for EPA600, 72% for EPA1800, and 61% for DHA600. The placebo group exhibited a 6% decrease in LDL‐C (n=26, P<0.01); the EPA600 group a 3% decrease in LDL‐C (n=27, NS), the EPA1800 group a 2% decrease in LDL‐C (n=29, NS); in contrast, the DHA group exhibited a 14% increase in LDL‐C (n=28, P<0.02). HDL and TG levels were relatively unaffected.

Conclusion

DHA, but not EPA, raised LDL‐C in normal lipidemic subjects at a dietary intake of 600 mg/day for 6 weeks. Funded by DuPont.
Dynamic changes in extracellular matrix gene regulation in adipose tissue and impact on preadipocyte proliferation and apoptosis
Authors: Ward Meliza Grace , Adapala Jitendra , Adedokun Sunday , Ajuwon Kolapo
Published: June 2021

Adipose expansion occurs by hypertrophy and hyperplasia which may be influenced by the extracellular matrix (ECM). In the current study, we observed adipose depot specific changes in ECM expression under diet induced obesity. We examined ECM transcript and protein levels in C57BL/6 mice fed a control or high fat diet for 4, 8, and 12 weeks. We report that the transcript levels of collagen1A1, collagen VI, and biglycan display increased expression in the high fat diet mice that shifts from the subcutaneous adipose to the epididymal adipose over time. Protein levels of collagen1A1 and collagen VI do not correlate with transcript levels. We saw changes in the expression of MMPs 3 and 13 (P < 0.05) in mice fed a high fat diet, suggesting that ECM degradation by MMPs may be a reason for the disparity between protein and transcript levels. This study indicates that ECM genes are differentially regulated in different depots. Also, transcripts and proteins of the ECM may not correlate in obesity, perhaps due to degradation by MMPs. In a separate study, we treated preadipocytes with biglycan, decorin and fibronectin to evaluate their effects on preadipocyte proliferation. Decorin and biglycan caused a significant reduction of preadipocyte proliferation (P < 0.05), while fibronectin stimulated preadipocyte proliferation (P < 0.05). Thus, we provide evidence that ECM genes may directly regulate preadipocyte proliferation.

Grant Funding Source: Purdue University
Regulation of skeletal muscle Troponin T alternative splicing in response to changes in body weight is impaired in obese rodents
Authors: Schilder Rudolf , Kimball Scot , Marden James , Jefferson Leonard
Published: June 2021

In insects, experimental manipulation of body weight results in precise adjustment of Troponin T (TnT) expression to the imposed weight by means of mRNA alternative splicing. The objective of the present study was to test the hypothesis that this mechanism functions similarly in mammals, and is impaired in mammalian models of obesity, in which the relationship between body weight and skeletal muscle performance is disrupted. To this end, the experienced body weight of Sprague‐Dawley rats was increased 30% by fitting them with lead‐weighted vests for 7 days, after which load‐bearing gastrocnemius muscles were examined for TnT splicing patterns. Similar to previous findings in insects, the pattern of TnT mRNA splicing rapidly changed to match that of control rats with actual body weight equivalent to the load‐bearing animals. In contrast, obese Zucker rats showed an impaired TnT splicing response across a range of body weight. Based on these findings in rats, we propose that TnT alternative splicing responses to body weight are dysfunctional in mammalian obesity, causing a mismatch between body weight and skeletal muscle composition and performance. Consequently, body‐weight inappropriate skeletal muscle TnT isoform expression may result in muscle weakness, a reduction in the willingness to participate in exercise, and a reduction in the rate of energy consumption. (Supported by NIH grant DK15658)
Diet‐induced obesity leads to decreased hepatic iron storage associated with inflammation
Authors: Chung Jayong , Kim Min Soo , Han Sung Nim
Published: June 2021

Increased risk for iron deficiency has been reported in obese subjects. We investigated the effects of high fat diet‐induced obesity on hepatic iron status and serum adipokine and inflammatory marker levels. Four‐ week old C57BL mice were fed diets containing 10 (ND) or 60 (HFD)% energy from fat for 16 wks. Consumption of HFD resulted in higher weight gain (16.3 vs. 30.4g). Serum leptin, total adiponectin, high molecular weight (HMW) adiponectin, and serum amyloid A (SAA) and hepatic non‐heme iron, ferritin, and hepcidin mRNA levels were measured. HFD group had higher leptin (42.6 vs. 104.3 ng/mL), and lower HMW adiponectin (4.80 vs. 3.67 ug/mL) levels. Higher level of SAA in HFD group (57.8 vs. 117.9 ug/mL) suggests inflammation in HFD‐induced obese animals. HFD group had lower hepatic non‐heme iron (3.12 vs 0.869 ug/mg protein) and ferritin levels. HFD group had lower hepcidin expression at 54% level of ND group, however, ratio of hepcidin expression to non‐heme iron was higher (2.5 fold higher in HFD than ND). Hepcidin is a homeostatic regulator of iron metabolism by restricting intestinal iron absorption, but, also known as a mediator of inflammation. Leptin and SAA showed positive correlation with weight gain while HMW adiponectin showed negative correlation. Increased SAA levels and higher hepcidin ratio to iron suggests that lower hepatic iron status in obese animals might be associated with inflammation. Supported by Korea Research Foundation Grant (C00305) and by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (2009‐0063409).
Loss of Beta‐Catenin leads to compensatory changes in adherens and other junctions
Authors: Awuah Prince , Wickline Emily , Monga Satdarshan
Published: June 2021

β‐Catenin signaling is important in liver pathobiology and a pivotal component of adherens junctions (AJ), connecting E‐cadherin and actin cytoskeleton. Here we query the hepatocyte‐specific β‐catenin‐conditional null mice (KO) for alterations in AJ or tight junctions (TJ). We demonstrate E‐cadherin‐β‐catenin association exclusively in epithelial cells in control livers. The KO livers exhibit a complete loss of β‐catenin and its association with E‐cadherin in hepatocytes. While total levels of α‐catenin, E‐cadherin and α‐actin were mildly decreased, KO livers showed increased γ‐catenin in total and cytoskeleton‐enriched lysates. While, E‐cadherin‐β‐catenin‐F‐actin association was evident in control livers, E‐cadherin‐γ‐catenin‐F‐actin association was evident exclusively in KO. No γ‐catenin nuclear translocation was evident in hepatocytes in KO livers, during increased proliferation, observed at 72h after partial‐hepatectomy. Notable changes in TJ proteins were evident in KO livers including increased total levels of junctional adhesion molecule‐A and claudin‐1, and decreased levels of claudin‐2. Thus, β‐catenin loss at the hepatocyte membrane is compensated by γ‐catenin, but it is incapable of nuclear transactivation functions in KO livers. Also, changes in several TJ proteins were evident after β‐catenin loss suggesting important crosstalk.
Adducins regulate remodeling of intercellular junctions in model human epithelia
Authors: Ivanov Andrei I , Naydenov Nayden G
Published: June 2021

Epithelial adherens junctions (AJs) and tight junctions (TJs) are dynamic structures readily undergoing disintegration and reassembly. Remodeling of AJs and TJs depends on orchestrated dynamics of the plasma membrane and the actin cytoskeleton, which implicates the membrane/cytoskeleton interface in junctional regulation. Spectrin‐adducin polymers link the plasma membrane to the actin cytoskeleton. We investigated roles of adducin in the remodeling of epithelial junctions. We used SK‐CO15 human colonic and HPAF‐II human pancreatic epithelial cells, which possess well‐formed AJs and TJs and express α‐ and γ isoforms of adducin. Both adducins colocalized with E‐cadherin and β‐catenin at mature and newly‐assembled AJs. siRNA‐mediated downregulation of α‐ and γ‐adducin expression in SK‐CO15 cells attenuated AJ reformation without affecting TJ assembly. Depletion of adducins decreased protein level of βII spectrin and dewnregulation of βII spectrin mimicked effects of adducins knock‐down on AJ reassembly. In HPAF‐II cell monolayers, disruption of apical junctions induced by phorbol ester was paralleled by phophorylation of adducins and their disappearance from intercellular contacts. Downregulation of α‐ and γ‐adducins accelerated phorbol ester‐induced AJ disassembly. These finding suggest novel roles for adducins in the establishment and stabilization of epithelial adherens junctions.
Yes‐associated protein expression is induced in hepatocellular carcinoma and is responsive to cell density.
Authors: Apte Udayan , Edwards Genea , Wan Yu‐Jui Yvonne , Guo Grace L. , Wolfe Andy
Published: June 2021

Hepatocellular Carcinoma (HCC) is the most common malignancy of the liver associated with high mortality. We are interested in understanding the role of pathways involved in organ size regulation in pathogenesis of HCC. Specifically, we are investigating the role of Hippo Kinase pathway and yes‐associated protein (Yap), the downstream effector of the pathway. Three HCC cell lines investigated, Hep3B, HepG2 and Huh7, demonstrated increase in Yap as compared to normal human hepatocytes. The expression levels and cellular localization of Yap was responsive to cell density. High cell confluency resulted in decreased Yap expression and nuclear export. siRNA‐mediated knockdown of Yap resulted in decreased cell proliferation of Hep3B cells. Immunohistochemical analysis of Yap in phenobarbital+diethylnitrosamine‐induced liver tumors in C57BL/6 mice, spontaneous tumors in Farnesoid X Receptor knockout mice and human HCC biopsies revealed extensive nuclear staining on Yap in highly proliferative tumors. These data indicate that Yap helps the hepatoma cells overcome the cell adhesion‐mediated growth inhibition and plays a critical role in pathogenesis of HCC.