bluuebunny/crossref_metadata_2025 huggingface dataset:
Leptin and lipids serum concentration on early pregnancy and 2nd and 3rd trimester blood pressure levels: A prospective cohort study in Rio de Janeiro, Brazil
Authors: Kac Gilberto , Farias Dayana Rodrigues , Franco‐Sena Ana Beatriz , de Jesus Thatiana , dos Santos Vaz Juliana
Published: June 2021

Introduction

Little is known about lipid profile during pregnancy and 2nd and 3rd trimester blood pressure levels (BPL).

Objective

To test the association of lipid profile early in pregnancy and the 2nd and 3th trimester BPL.

Methods

Prospective cohort of 226 pregnant women followed at 8–13th, 22–24th and 30–34th weeks. The main covariates were total cholesterol, triglycerides, high‐density lipoprotein (HDL‐c), low‐density lipoprotein (LDL‐c) and leptin. The outcome was diastolic blood pressure (DBP) and systolic blood pressure (SBP) variation from the 2nd to the 3rd trimester. Analyses were performed with linear mixed effect models, controlling by obstetric and socioeconomic variables.

Results

Time elapsed between the 2nd and 3rd trimester and pre‐pregnancy body mass index were associated with DBP and SBP. Triglycerides (SBP: β=0.0638, p=0.010), total cholesterol (SBP: β=0.0533, p=0.017; DBP: β=0.0319, p=0.077) and LDL‐c (SBP: β=0.0756, p=0.010; DBP: β=0.0475, p=0.029) were also associated with DBP or SBP. First trimester leptin levels were associated with SBP (β=0.1311, p=0.001) and DBP (β=0.102, p<0.001).

Conclusion

Our results showed that leptin and lipid profile early in pregnancy might play a role on the BPL change from the 2nd to the 3rd trimester.
Effect of pistachios on lipids, lipoproteins, glucose metabolism, and insulin sensitivity in type 2 diabetes
Authors: Sauder Katherine A , McCrea Cindy E , Kris‐Etherton Penny M , Ulbrecht Jan S , West Sheila G
Published: June 2021

Controlling blood sugar and dyslipidemia in diabetes is important for reducing cardiovascular morbidity and mortality. This study compared the effect of two diets on lipids, lipoproteins, glucose metabolism, and insulin sensitivity. We enrolled 28 adults with type 2 diabetes in a randomized, crossover, controlled‐feeding study with 4wk diet periods. After a 2 wk run‐in on a typical Western diet, participants consumed a low fat control diet and an isocaloric moderate fat pistachio diet, in which pistachios contributed 20% of energy. At the end of each diet period, we assessed lipid and glycemic parameters while fasted and during a standard 75g oral glucose tolerance test. Compared to baseline, the control diet increased fasting triglycerides (140 vs 164 mg/dl) and the total:HDL cholesterol ratio (4.0 vs. 4.3), but these parameters were unaffected by the pistachio diet (142 mg/dl and 4.0, respectively); this differential response was statistically significant (all p<0.01). Glucose and insulin levels were not affected by the diets; however, glycated hemoglobin was reduced from baseline following both diets, with significantly larger reductions following the pistachio diet than the control diet (6.19% vs 6.02% and 6.07%, respectively, p=0.03). Taken together with other recent studies, these results provide evidence that pistachio consumption can benefit insulin sensitivity in adults with type 2 diabetes.

Grant Funding Source: American Pistachio Growers
Fatty acid transport protein 1 mediates macrophage eicosanoid metabolism
Authors: Qin Yuanyuan , Freemerman Alex Jay , Li Lei , Coleman Rosalind , Galanko Joesh , Edin Matthew , Zeldin Darryl , Stahl Andreas , Makowski Liza
Published: June 2021

The fatty acid transport protein (FATP) is expressed in tissues with active lipid metabolism including macrophages (MPs). FATP1 is a long and very long chain fatty acyl‐CoA synthetase (ACS). Preliminary data in RAW264.7 MPs over‐expressing (OE) FATP1 showed increases in ACS activity along with a blunting of proinflammatory mediators compared to empty vector (EV); while FATP−/− bone marrow derived MPs (BMDMs) displayed blunted ACS activity with elevations in IL‐6, TNFα and MCP‐1 compared to FATP+/+. We hypothesize that FATP1 modulates availability of fatty acids as fuel or as substrates for eicosanoid synthesis. We aim to investigate if FATP1 modulates eicosanoid metabolism and inflammation in MPs. MPs were treated with 5ng/mL LPS and 10 ng/ml IFNγ to polarize to the pro‐inflammatory M1 subtype, or left untreated. Liquid chromatography mass spectrometry results showed FATP1‐OE drove statistically significant increases in PGD2, PGF2α, 8isoPGF2α and TXB2, and decreases in proinflammatory 11, 12, 15‐HETEs, vs. EV. FATP1‐OE also had lower levels of AA compared to EV through metabolomics. Complementary to OE, FATP1−/− displayed elevated 8, 11, 12, and 15‐HETEs. Future directions will examine FATP‐1 mediated oxidation of AA and incorporation into lipids in macrophages. In conclusion, FATP‐1 decreases MPs inflammation potentially through regulation of eicosanoid production. AA017376

Grant Funding Source: R00 AA017376
Hypoxia‐Induced Heparan Sulfate Primes the Extracellular Matrix for Cell Recruitment by Facilitating VEGF‐Fibronectin Interactions
Authors: Buczek‐Thomas Jo Ann , Rich Celeste B. , Nugent Matthew A.
Published: June 2021

Vascular endothelial growth factor (VEGF) is a signaling protein that drives angiogenesis and the dysregulation of the VEGF system contributes to several disease states. With disease onset, extracellular matrices (ECM) experience dramatic changes in pH and composition that can affect cellular response. Within the ECM, fibronectin (Fn) is the major binding site for VEGF and heparan sulfate (HS) present in the ECM catalytically alters Fn structure to enhance VEGF‐Fn interactions and subsequent cell activation. In the present study, we investigated the role of heparan sulfate isolated from normoxic and hypoxic cells in modulating VEGF‐Fn interactions. For these studies, retinal pigmented epithelial (RPE) cells were cultured under normoxia or hypoxia (pO2 1%; 72 hours) prior to HS isolation by chromatographic methods. ELISA analysis indicated that hypoxia treatment induced changes in the amount and structure of the HS produced. 125I VEGF binding to Fn pretreated with normoxic or hypoxic HS indicated hypoxia‐derived HS enhanced VEGF binding to Fn while HS from normoxic cells lacked significant catalytic activity. VEGF receptor chimera binding assays indicated preferential binding of VEGF‐Fn to VEGFR2 over VEGFR1 and endothelial cell attachment was enhanced on RPE cells maintained under hypoxic conditions. These results indicate that hypoxia primes the ECM through the action of HS on Fn to become a depot for VEGF.
Bioaccessibility of all trans‐Astaxanthin from Salmon
Authors: Chitchumroonchokchai Chureeporn , Failla Mark L
Published: June 2021

The keto‐carotenoid astaxanthin (AST) is not typically present in human plasma due to its relative scarcity in the human diet. However, the reported health‐promoting properties of AST have aroused interest among both researchers and consumers. Salmon, and especially wild salmon, is the major food source of AST. The purpose of this study was to investigate the digestive stability, bioaccessibility and apical uptake of AST in wild salmon using a couple in vitro digestion and Caco‐2 cell model. All trans‐AST was the predominant carotenoid in wild salmon, whereas commercial AST supplements contain all trans AST‐esters. Recovery of AST following simulated gastric and small intestinal digestion was 88%. Approximately 32% of AST partitioned in the aqueous fraction of chyme during small intestinal of raw and broiled salmon and not altered by inclusion of 2% (vol/wt) soybean oil (31.6 vs 33.8%, respectively). Accumulation of AST by Caco‐2 cells was proportional to duration of incubation and concentration of micellar AST in medium. These data suggest that AST from salmon is highly bioaccessible.

Grant Funding Source: Ohio Agricultural Research and Development Center
Compensatory mechanisms acting in dystrophin deficient hearts
Authors: Rossi Marcos A , Blefari Valdecir , Ferezin Patricia , Baruffi Marcelo D
Published: June 2021

Duchenne muscular dystrophy (DMD), the best‐known form of muscular dystrophy, is due to mutation on the chromosome X that prevents dystrophin production. Dystrophin is responsible for protecting sarcolemmal integrity, its absence turning striated muscle cells, skeletal and cardiac, more vulnerable to disruption and death. Despite the better knowledge on basic pathological mechanisms, there is no cure for DMD, patients usually dying due to muscle‐based breathing and heart problems. The compensatory mechanisms related to dystrophin deficiency are partially known. Subsarcolemmal expression of utrophin, a protein analogue to dystrophin, is a well‐known compensatory mechanism to dystrophin deficiency. mdx mice, an experimental model of DMD, present increased expression of utrophin, which would provide the compensation to dystrophin absence. This would explain the reason of an mdx mice life expectancy similar to that of WT controls. Considering that double‐knockout mdx:utr−/− mice can live up to 20 weeks of age, similarly to a human patient with both dystrophin and utrophin deficiency, other compensatory mechanisms should be working. This study demonstrates, for the first time, cardiac intercalated disc remodeling characterized by overexpression of adhesion molecules implicated in specialized mechanical and electrochemical structures, functioning as additional compensatory mechanisms in mdx mice.
Bile acids elicit production of Interleukin‐23 by hepatocytes
Authors: O'Brien Kate M , Copple Bryan L
Published: June 2021

Interleukin‐17A (IL‐17A) levels are increased in patients with cholestatic liver disease, and promote inflammation in mouse models of cholestasis. IL‐23 is important for the maintenance of Th17 cells, which produce IL‐17A during cholestasis. The mechanism by which IL‐23 levels are increased in the liver during cholestasis are not known. We tested the hypothesis that bile acids, which are increased in concentration during cholestasis, upregulate IL‐23 in hepatocytes. IL‐23 mRNA and protein levels were increased in the livers of mice fed a diet containing 0.3% cholic acid. Similarly, treatment of primary mouse hepatocytes with taurocholic acid (TCA) increased IL‐23 mRNA and protein levels. Inhibition of sphingosine‐1‐phosphate receptor 2 (S1PR2) or the epidermal growth factor receptor (EGFR) did not prevent upregulation of IL‐23 by bile acids, suggesting that bile acids upregulate IL‐23 in hepatocytes by a distinct mechanism. Next, the involvement of JNK and p38 signaling were investigated. Whereas JNK inhibition did not affect upregulation of IL‐23 by TCA, inhibition of p38 enhanced upregulation of IL‐23. Collectively, these data demonstrate that TCA upregulates IL‐23 in hepatocytes independent of S1PR2 or EGFR signaling, and that bile acids may be important activators of the IL‐17/IL‐23 axis during cholestasis. Supported by NIH grant DK073566
Putting Fat to Work: Therapeutic Possibilities for Adipose Tissue and Cells
Authors: Katz Adam J.
Published: June 2021

Adipose Tissue is a unique biological resource capable of providing vast amounts of matrix, bioactive factors, and a variety of cell types. Due to its unmatched abundance, expendability, ease of harvest, and mass donor appeal, adipose tissue lends itself to a variety of therapeutic strategies. In addition, both adipose tissue proper, as well as adipose‐derived cell fractions, are being tested for safety and efficacy in the context of a wide range of clinical applications such as scar remodeling, soft tissue replacement and augmentation, wound healing, cardiac disease, Crohn's disease, reconstruction of bony defects and many others. This presentation will highlight adipose‐related clinical studies/applications that are imminent and/or currently in progress, with discussion of the regulatory, clinical and commercial considerations associated with a given strategy.
Memory and Cognitive Load Theory in Anatomical Education
Authors: Regpala Steffi , Easteal Ronald
Published: June 2021

A major component of academic development is the improvement of teaching by helping students to consolidate information from short‐term to long‐term memory. Recent advances in Memory and Cognitive Load Theory would seem to be pertinent to the teaching and learning of anatomy. In order to test the efficacy of these learning techniques, students in a large gross anatomy class (n = 280) were exposed to the following teaching innovations ‐ testing for learning, delayed practice, interleaving, and spiral learning. The performance of the students will be analyzed by comparing the marks to a previous class that took the same final exam. Comparisons will be made between the whole class, but also between the lower third, the middle third and the upper third. These results will be tabulated and analyzed by January 2013. The hypothesis is that there will be an increase in test scores, particularly in the lower third.
Protein Tyrosine Phosphatases: Critical Regulators of Signaling in Cancer
Authors: Tonks Nicholas K.
Published: June 2021

The protein tyrosine phosphatases (PTPs) are now recognized as critical regulators of signal transduction under normal and pathophysiological conditions. These enzymes belong to a family of cysteine‐dependent phosphatases, which are characterized by a conserved ‘C[X]5R’ motif and hydrolyze phosphoester bonds in proteins and non‐protein substrates. Overall, the objective of the lab is to examine PTP regulation and function in cell and animal models, and to define the role of PTPs in critical tyrosine phosphorylation‐dependent signaling events in human disease. Currently, there are four broad areas of research in the lab covering (i) functional analysis of members of the PTP family, (ii) redox regulation of PTP function, (iii) development of novel approaches to therapeutic intervention in PTP function, and (iv) characterization of a knockout mouse model to define the function of JSP1, a member of the PTP family that is a novel regulator of MAP kinase signaling. I will discuss how these studies are leading to identification of novel therapeutic targets from among the PTP family. There is a perception in industry that the members of the PTP family are “undruggable”; however, I will illustrate how a detailed understanding of the structure and function of PTPs has suggested new approaches to the development of small molecule drug candidates that target these enzymes.
Lipoprotein Lipase Affects Macrophage Content and Phenotype in Aorta and Adipose Tissue
Authors: Chang Chuchun Liz , Garcia‐Arco Itsaso , Kim Ji Young , Goldberg Ira J , Deckelbaum Richard J
Published: June 2021

Macrophages (Mq) link inflammation to atherogenesis and insulin resistance. We have reported that dietary n‐3 fatty acids decrease arterial lipoprotein lipase (LpL) and Mq. We now questioned whether LpL can direct tissue Mq trafficking. Transgenic LpL knockout mice rescued with muscle LpL expression (MCKL0) and MCKL0 transplanted with bone marrow (BM) w/ or w/o LpL expression were used to study Mq in aorta and adipose tissue. Immune cells and interacting factors were examined by immunofluorescence, RT‐PCR, or flow cytometry. LpL deletion reduced arterial Mq by >; 30%, which was restored by reconstitution of LpL‐expressing BM. By contrast, in adipose tissue, MCKL0 had a 50% increase in Mq content and >; 5‐fold increase in expression of chemotactic MCP‐1/CCR‐2 and anti‐inflammatory M2 markers (p<0.05). Interestingly, increased Mq‐associated markers were found in adipose tissue and adipocytes, but not in stromal vascular cells, in MCKL0. In blood, MCKL0 have total leukocytes, neutrophils and monocytes ~ 40% lower than control (p<0.05). Inflammatory Gr‐1hi monocytes were decreased by 25%, whereas Gr‐1lo monocytes were increased by 2 fold, in MCKL0 (p<0.05). These data suggest that LpL affects local Mq content and phenotype, in part, via altering immune cell profiling. In the absence of LpL, we hypothesize that a self‐adaptive mechanism that causes adipocytes to produce pro‐inflammatory mediators might exist.

Grant Funding Source: NIH‐HL40404 (RJD); T32‐DK007674/HL007343 (CLC)
Need for Nutrition Education Programme: Laying the foundations of nutrition knowledge relevant to clinical and public health practice
Authors: Ray Dr Sumantra , Laur Celia , Group NNEdPro
Published: June 2021

The Need for Nutrition Education Programme is an independent educational innovation and evaluation programme with 2 phases. The objective of Phase 1 was to measure the effectiveness of a nutrition education intervention for medical students undertaking clinical training. The objective of Phase 2, Nutrition Education and Leadership for Improved Clinical Outcomes, was to assess if a training intervention incorporating clinical/public health nutrition and change management/leadership strategies, could equip junior doctors to improve nutrition awareness in UK hospitals. Phase 1 involved training weekends on clinical nutrition for 4th year medical students. Two and a half years later, 3 participants from these cohorts joined NELICO and recruited up to 3 additional junior doctors from their hospitals. The 3 teams attended a training weekend based on the objectives, equipping them to run a hospital Nutrition Awareness Week. Knowledge, attitudes and practices evaluated at baseline and post training improved significantly from baseline to 4 months for Phase 1 (p≤0.0001) and Phase 2 (p=0.03). Qualitative feedback was collected in both phases. Junior doctor led training sessions during the weeks were found to be particularly effective when combined with input from the hospital dietetics team. The weeks were considered useful by those involved and led to a wealth of lessons learned on how to improve hospital nutrition.
Innovative Postdoctoral Fellowship in Medical Nutrition
Authors: Ettinger Susan E. , Nasser Jennifer , Engelson Ellen , Albu Jeanine , Hashim Sami , Pi‐Sunyer F. Xavier
Published: June 2021

The New York Obesity and Nutrition Research Center (NYONRC) aims to reduce the incidence of obesity and related diseases through leadership in research, education and patient care. To enhance interdisciplinary collaboration around nutrition and disease, we are developing a curriculum to train postdoctoral Medical Nutrition Specialists (MNS) in the language and practice of medicine and in the methodology and interpretation of clinical research. The 11 month fellowship provides intensive study at the interface of nutrition with medicine. Trainees develop facility with clinical research methodology, undertake supervised observerships in diverse medical disciplines at the level of the third year medical student, and work closely with faculty mentors to develop a translational nutrition focus. To date we have trained three postdoctoral fellows, all holding university faculty positions in nutrition. In our hands, this innovative “train the trainer” approach has potential to develop a MNS competent to work across disciplines from “bench to bedside”. The MNS can serve both as an expert resource in the use of nutrition as adjuvant therapy for the prevention and management of chronic disease, and develop collaborations with medical disciplines to test clinical nutrition hypotheses. Program development is supported by an R25E grant from NIDDK.
An expert‐like explanatory framework for learning cellular and molecular mechanisms
Authors: Trujillo Caleb , Pelaez Nancy
Published: June 2021

Experts and novices differ in how they process, retrieve, and manipulate information. However, expertise is specific to a given domain. We examine how biologists explain cellular and molecular mechanisms. Our research is guided by two questions. First, what patterns exist when expert biologists provide mechanistic explanations? Second, how do the explanations of biologists vary among sub‐disciplines? Using a published model to guide our investigation, we conducted interviews with the Three Phase Single Interview Technique. A dual coding scheme was applied once interviews were transcribed. Data was analyzed using thematic analysis and corroboration. In spite of some differences, findings support previous reports claiming that biologists focus on entities, the states of entities, activities, and temporal and spatial organization, but in addition, we found that biologists in all sub‐disciplines contextualize explanatory mechanisms in the systems and research techniques they use. We conclude that explanations from our expert biologists connect the process of investigation to both factual and conceptual knowledge of cellular and molecular mechanisms.
Dental microwear and diet of white‐tailed deer through its North and Central American Range
Authors: Dewar Eric Walter , Hernandez Susan M.
Published: June 2021

We investigated the dietary ecology of the white‐tailed deer Odocoileus virginianus using enamel microwear with a stereomicroscope at low magnification (35×). These 96 adult white‐tailed deer were museum specimens that were collected throughout North and Central America; we divided them into five biogeographic regions to determine any differences in diets through their sampled range. Our observations indicated a soft browsing diet for this wide‐ranging generalist species that was quite consistent throughout its range, but with noticeable regional variations. It is possible that this diet is a result of its modern commensality with humans and having a preference for habitat‐edge environments. We found that its diet in Massachusetts and New York reflected a habitat that is more open than the northern New England individuals. We found the most noticeable differences between the extreme northern and southern ends of its Northern American range. Odocoileus virginianus by itself is not an ideal habitat indicator due to its generalized niche, but it does help to characterize a particular habitat‐edge niche common to many New World habitats.
Estrogens Control Inflammatory Mediators in Experimental Colitis
Authors: Hussein Inaya Abdallah Hajj , Maksoud Rony , Jambart Stephanie , Diab Rami , Assi Tarek Bou , Barada Kassem , Eid Assaad , Jurjus Rosalyne , Reimund Jean‐Marie , Jurjus Abdo
Published: June 2021

Objectives

It is to investigate the effect of Eestrogen (E2) in the management of colitis in a panel of models, focusing on morphological changes, activity of mast cells, expression of cytokines (IL‐1β, IL‐6, and TNF‐α), and extracellular matrix as well as ROS.

Materials and Methods

200 male Sprague‐Dawley rats, weighing 250 to 300g, were divided into: Group I induced with colitis, not receiving treatment, Group II induced with colitis and treated with estrogen (17β‐estradiol), Group III receiving E2 only, Group IV provided with Saline. In groups I and II colitis was induced according to reported procedures by authors. Daily observations of signs and symptoms were performed. Macroscopic, microscopic evaluations and molecular analysis were done on tissues on days 7, 14, 28 and 56.

Results

There was amelioration of the estrogen treated rats health: inflammation scores were reduced by 10%, number of mast cells in the colon decreased by 30%, fibronectin expression was only 50%, and collagen IV was minimal or even disappeared completely. There was a significant decrease in TNF‐α. IL‐6, and IL‐1β expression by 25%. In addition, ROS decreased significantly by 30% in the E2 treated rats.

Conclusions

There was improvement in the IBDs inflammatory status in all E2 treated groups at all time points of the experiment. There was, also, less necrosis of tissues as depicted by less collagen IV, fibronectin as well as antioxidant effect.
Characterization of mast cells in the wall of the cerebral arterial systems in the rat and the baboon
Authors: Gichinga Harry N , Miller Kenneth E , Anderson Michael B , Meek Bill D
Published: June 2021

Rat brain perivascular mast cells have been characterized histochemically and ultrastructurally in other studies (Dimitriadou, 1990). In our earlier studies in the vervet monkey circulus arteriosus, cells resembling mast cells were seen within the tunica adventitia. In our current studies on whole mount preparations of arterial vessels, branching from the circulus arteriosus in both the rat and the baboon, labeling experiments with mast cell tryptase and confocal immunofluorescent microscopy show that mast cells do exist in the wall of the vessels in the two animal species. Fluorescent immunohistochemistry studies of the arterial vessels using serotonin antibody have shown that the mast cells contain serotonin in their granules. Colocalization of mast cell tryptase and serotonin confirmed that these are in the same cell. Colocalization of mast cell tryptase and tryptophan hydroxylase confirmed that serotonin synthesis occurred in the same cell. Other studies will attempt to determine the density of the mast cells in the wall of the vessels.

Grant Funding Source: Department of Anatomy and Cell Biology OSU Center for Health Sciences
Role of Disabled protein 2 (Dab2) in Vascular Endothelial Growth Factor Receptor‐2 signaling, trafficking, and vascular morphogenesis
Authors: Inamdar Shivangi M , Jung Jae‐Joon , Choudhury Amit
Published: June 2021

The formation of blood vessels occurs through the process of vasculogenesis or angiogenesis. Angiogenesis plays a crucial role physiological and pathological conditions. Vascular endothelial growth factor receptor 2 (VEGFR2) is one of the key regulators of angiogenesis. Plasma membrane (PM) level of VEGFR2 is regulated by endocytosis and secretory transport processess. VEGF‐binding to VEGFR2 induces phosphorylation of the receptor, endocytosis, and signal transduction process that leads to vascular morphogenesis. Disabled protein 2 (Dab2) is a cytosolic adaptor protein known to function in endocytosis, cell adhesion, and hematopoetic cell differentiation. However, how Dab2 regulates VEGFR2 function at the PM and endosomal level is still not clear. Our results show that depletion of Dab2 decreases VEGFR2 levels and VEGF‐induced phosphorylation of the receptor. Moreover, Dab2 knockdown cells show loss of cell‐cell junction and an inability to form tube structures in response to VEGF stimulation. Thus, our data demonstrate that Dab2 may function in the vascular morphogenesis by regulating VEGFR2 phosphorylation and trafficking.
The pivotal role of p53 in doxorubicin‐induced acute versus chronic cardiotoxicity
Authors: Zhu Wuqiang , Reuter Sean , Wagner Gregory R , Payne Ronald M , Field Loren J
Published: June 2021

We examined the role of p53 in doxorubicin (DOX)‐induced acute and chronic cardiotoxicities with a clinically relevant juvenile mouse model. Two week old MHC‐CB7 mice (which express dominant‐interfering p53 in cardiomyocytes, CMs) and their non‐transgenic (NON‐TXG) littermates were given weekly DOX injections for 5 weeks (25 mg/kg total dose). Animals were studied 1 week (acute stage) or 13 weeks (late stage) after last DOX injection. Cardiac function was measured with echocardiography. CM apoptosis was quantified using immunohistology. During acute stage, cardiac function was preserved (Fractional Shortening, FS, 58±2.0% vs. 45±1.3%, p<0.01) and CM apoptosis was reduced (0.003±0.002/mm2 vs. 0.011±0.002/mm2, p<0.01) in CB7 mice vs. NON‐TXG mice. During late stage, cardiac function in CB7 mice markedly deteriorated, reaching values similar to those in NON‐TXG mice (FS=52±2.5% vs. 50±2.0%, p>;0.05). CM apoptosis was elevated in CB7 mice as compared to NON‐TXG mice (0.076±0.007 mm2 vs. 0.042±0.008 mm2, p<0.01). In conclusion, although inhibition of p53 activity protects against DOX‐induced CM apoptosis and preserves cardiac function during acute stage, it exacerbates CM apoptosis and cardiac dysfunction during late stage. We are determining the correlation between mitochondrial DNA damage during acute stage and CM apoptosis during late stage.

Grant Funding Source: NIH, American Cancer Society
Reciprocal interactions between mitral valvular endothelial and interstitial cells regulate endothelial‐to‐mesenchymal transformation and myofibroblast activation
Authors: Shapero Kayle , Bischoff Joyce , Mayer John
Published: June 2021

Mitral valve pathologies are characterized by thickening of the valve leaflets, activated myofibroblasts, and excessive matrix remodeling. The mechanisms leading to these alterations are not well‐understood due to a lack of understanding of valve endothelial cells (VEC) and valve interstitial cells (VIC), and how the two cells interact to maintain valve structure and function.

Hypothesis

We propose that VEC‐VIC interactions are required for normal growth, integrity and function of valves.

Results

We characterized mitral VEC and VIC populations isolated from ovine mitral valves. We modeled VEC‐VIC interactions in vitro using indirect co‐culture in Transwells. In these assays, VICs suppressed TGFβ‐mediated endothelial‐to‐mesenchymal transformation (EndMT) in the VECs. Conversely, co‐culture of VECs and VICs suppressed the activated myofibroblast phenotype in VICs.

Conclusions

These results suggest that interactions between VEC and VIC are important for 1) suppressing EndMT in VECs and 2) suppressing the activated VIC phenotype. Healthy adult mitral valves exhibit little to no EndMT or activated VICs, two cellular processes implicated in valve disease. We speculate that disturbance of reciprocal interactions between VEC and VICs in vivo may contribute to pathologies characteristic of cardiac valves.

Supported by internal funding and the Leducq Foundation Mitral Valve Network Grant.
Genome‐wide association studies of severe communication processes and affectation of multiple prevalent pediatric communication disorders
Authors: Eicher John Dickinson , Powers Natalie R. , Gruen Jeffrey R.
Published: June 2021

Impairments in communication skills are commonly seen in schoolchildren, including in the prevalent disorders dyslexia or RD, language impairment (LI), and autism spectrum disorders (ASD). Children with these disorders are difficult to identify, frequently have academic underachievement, and have limited socioeconomic opportunities. Therefore, we performed a genome wide association study in the Avon Longitudinal Study of Parents and Children using two distinct strategies: (1) examining severe deficits in core communication processes and (2) dissecting the gene risk factors of having multiple impairments. For severe communication deficits, the strongest associations were seen within RD risk locus DYX2, within LI risk locus SLI2, and a novel locus on 4p15.1. We first examined disorders individually and then cases with multiple disorders. The strongest associations with LI were with the genes ZNF385D, IL26, and NDST4. Next, we examined cases with multiple disorders. With cases affected with both ASD and RD, the strongest associations were with HTRA1 and a locus on 1q31.3. For cases with both RD and LI, we saw the strongest associations with ZNF385D and COL4A2. For ASD and LI cases, the strongest associations were with SGMS2, CLDN10, and BTLA. Our results confirm the DYX2 and SLI2 loci in communication disorders and implicate genes previously associated with other neurobehavioral disorders.
The effect of electrical stimulation and testosterone on the expression of regeneration‐associated genes
Authors: Meadows Rena Marie , McMillan Kathryn P. , Batka Richard J. , Brown Todd J. , Jones Kathryn J.
Published: June 2021

Despite robust regenerative potential following peripheral nerve injury, suboptimal outcomes often result in clinical situations. Our laboratory has recently shown that electrical stimulation (ES) and testosterone propionate (TP) can target two different phases of the regeneration process: delay time before sprout formation and regeneration rate, respectively. Furthermore, our laboratory has recently published that the combinatorial treatment of ES and TP significantly increased the expression of several regeneration‐associated genes (RAGs) compared to untreated animals after facial nerve crush injury. Since lower limb nerve injuries following trauma comprise a significant portion of peripheral nerve injuries, we investigated whether the combinatorial treatment of ES and TP improves axonal regeneration after injury to the sciatic nerve. We examined whether the expression profile of RAGs seen after facial nerve crush injury also occurred after sciatic nerve crush injury. To test this, rats received a crush injury to the sciatic nerve. Following injury, animals received either no treatment or treatment with ES and/or TP. After treatment, animals were euthanized at 6 hrs and 1, 2, 7, and 21 days post‐crush. Differences in mRNA expression of RAGs between the different treatment groups was determined by qPCR.

Grant Funding Source: Indiana University Collaborative Research Grant
A single residue unique to DinB‐like proteins limits formation of the Pol IV multi‐protein complex in Escherichia coli
Authors: Cafarelli Tiziana Moccia , Rands Thomas J. , Benson Ryan W. , Rudnicki Pamela A. , Lin Ida , Godoy Veronica G.
Published: June 2021

The mechanisms which regulate the activity of DinB, the most evolutionary conserved error‐prone Y‐family DNA polymerase, are only beginning to be understood. We focused on the regulation of DinB by protein‐protein interactions. We identified two conserved residues, Cysteine 66 (C66) and Proline 67 (P67), which are predicted to be non‐catalytic and are unique among DinB‐like proteins. We constructed DinB(C66A) and found that it co‐purifies with its interacting partners, RecA and UmuD, to a greater extent than DinB. We confirmed in vitro that DinB(C66A) has a higher affinity for RecA and UmuD relative to DinB, but note that the increased affinity of DinB(C66A) for UmuD is RecA‐dependent. Expression of dinB(C66A) from the chromosome resulted in detectable differences in lesion bypass fidelity and homologous recombination. The study of DinB(C66A) has revealed a key interface, which modulates the strength of interaction, and has suggested a binding order of RecA and UmuD to DinB. Uncovering the regulatory mechanisms of Y‐family DNA polymerases will permit their manipulation to deter acquisition of antibiotic resistance and to gain insights into cancer development.
Interconverting conformations of slipped‐DNA junctions formed by trinucleotide repeats affect repair outcome
Authors: Slean Meghan , Reddy Kaalak , Wu Bin , Edamura Kerrie Nichol , Kekis Mariana , Nelissen Frank , Aspers Ruud , Tessari Marco , Schärer Orlando , Wijmenga Sybren , Pearson Christopher
Published: June 2021

Slipped‐strand DNAs, formed by out‐of‐register mispairing of repeat units on complementary strands, are transient intermediates in repeat length mutations causing at least 30 neurodegenerative diseases. Expansions of (CTG)•(CAG) repeated DNAs are the mutagenic cause of 14 neurological diseases, likely arising through the formation and processing of slipped‐strand DNAs. The three‐way slipped‐DNA junction, at which the excess repeats slip‐out from the duplex, is a poorly understood feature common to these mutagenic intermediates. Here, we reveal that slipped‐junctions can assume a surprising number of interconverting conformations where the strand opposite the slip‐out is either fully base‐paired, or has one‐ or two‐unpaired nucleotides. These unpaired nucleotides can also arise opposite either of the non‐slipped junction arms. Junction conformation can alter correct nick‐directed repair levels. Junctions that have the potential to contain unpaired nucleotides are repaired with a significantly higher efficiency than constrained fully‐paired junctions. Surprisingly, certain junction conformations are aberrantly repaired to expansion mutations: mis‐direction of repair to the non‐nicked strand opposite the slip‐out leads to integration of the excess slipped‐out repeats rather than their excision. Thus, slipped‐junction structure can determine whether repair attempts lead to correction or expansion mutations.

Funding: Canadian Institutes of Health Research (CIHR MOP97896) (C.E.P.); National Institutes of Health (GM080454) (O.S.); the Chemistry section of the Dutch Science Organization (S.S.W.)
Investigation of the functions of new genes involved in repair of DNA double‐strand breaks in Saccharomyces cerevisiae
Authors: Sanderson Brian A. , Lewis L. Kevin
Published: June 2021

Chromosomal DNA is constantly damaged by internal chemical and enzymatic processes and by external agents such as radiation and chemicals in the environment. Potentially lethal lesions induced by many agents are DNA double‐strand breaks (DSBs) within the chromosome. Repair of DSBs is critical for prevention of mutations and chromosome instability, which increase the risk of cancer and cell death. Eukaryotes repair these lesions via two conserved pathways, homologous recombination and nonhomologous end‐joining (NHEJ). The goal of this project is to improve our understanding of the genes and metabolic pathways required for efficient repair of broken DNA. Previous studies used a yeast deletion strain library to identify mutants that were unable to repair gamma radiation‐induced damage. In the current study, a subset of these mutants were characterized that cannot repair DNA DSBs induced by in vivo expression of EcoRI endonuclease or the chemicals methyl methanesulfonate (MMS) and bleomycin. Most of the 73 new genes identified in this work have not previously been associated with DNA repair. Forty‐one of the genes are known to affect nuclear processes. The functions of many of these genes in homologous recombination and maintenance of chromosome stability are being assessed using genetic and physical assays of DNA repair. This research is supported by an NIH AREA R15 grant to L.K. Lewis.
Capturing the transient, in vivo binding partners of transcriptional activators using a genetically incorporated photo‐crosslinking amino acid
Authors: Dugan Amanda , Mapp Anna K.
Published: June 2021

Transcriptional activators are modular, signal responsive proteins that play an essential role in regulating gene expression. When localized to the nucleus, activators engage in a wave of interactions with a suite of multi‐protein coactivator complexes, resulting in their recruitment to the promoter of the gene to be transcribed. While the majority of methods available for studying protein‐protein interactions (PPIs) are ideal for studying those of higher affinity, few are well‐suited for studying PPIs of a more moderate affinity, including activator‐coactivator interactions. Recently, covalent crosslinking using a photoactivatable amino acid (Bpa) has proven to be a powerful method for the in vivo capture of moderate affinity PPIs. Herein we use in vivo photocrosslinking to examine the interaction between the amphipathic activator VP16 and the essential transcription factor TBP in live yeast. Several lines of evidence suggest that TBP is recruited to promoters through a direct interaction with VP16; However, in vivo co‐localization studies suggest that this recruitment occurs through an indirect mechanism. Using this methodology, we find that VP16 does in fact directly interact with TBP and that this interaction is sustained on DNA. We also find that TBP is a shared target of other amphipathic activators, suggesting a common mechanism of recruitment within a single family of activator proteins. Thus, this methodology should be useful in studying regulatory proteins involved in complex interaction networks. This project is funded by NIH‐NIGMS 2R0106553.
Study on the anti‐atherosclerotic mechanisms of immune tolerance induced by heat shock protein 60
Authors: Hao Chunyan , Duan Hubin , Li Shuzhen , Wang Suping , Xiao Chuanshi , Liu Xuejun , Xi Ling , Wang Fengzhi
Published: June 2021

Backgroud and purpose

To study the anti‐atherosclerotic mechanisms of immune tolerance induced by Heat shock protein 60 (HSP60)

Methods

40 male SD rats were randomly divided into healthy control group, atherosclerosis group (AS group), H1 group (oral HSP60 before modeling AS) and H2 group (oral HSP60 after modeling AS). The content of CD36, SR‐A, NF‐κB, HSP60 and regulatory T cells (Treg) in the aorta, lymph nodes and peripheral blood were detection by immunohistochemistry, flow cytometry, Western blot, PCR and ELISA. The intimal and vessel diameter ratios were calculated by the image analysis system.

Results

The levels of Treg cells in blood and lymphoid tissue increased. The pathological lesions of H1 group lighter than that of H2 group. The gene and protein expression of HSP60, SR‐A, CD36, NF‐κB in aorta of AS group were higher than that in the control group.The level of expression in the H1 group was lower than that in the H2 group. (P <0.05).

Conclusion

The immune tolerance induced by oral HSP60 could inhibit the arteries immune and inflammatory response, reduce the intimal injury and HSP60 antigen exposure and the degree of autoimmune response. Thereby it could also inhibit smooth muscle hyperplasia and maintain the stability of the fibrous plaques. Moreover, the earlier the oral HSP60, the better anti‐atherosclerosis effect.
NOL11, implicated in the pathogenesis of North American Indian Childhood Cirrhosis, is required for pre‐rRNA transcription and processing
Authors: Baserga Susan , Freed Emily , Prieto Jose‐Luis , McCann Kathleen , McStay Brian
Published: June 2021

The R565W mutation in the C‐terminus of the nucleolar ribosome biogenesis factor, hUTP4/Cirhin, causes North American Indian childhood cirrhosis (NAIC). Our objective was to identify non‐conserved interaction partners for hUTP4/Cirhin, as a defective protein‐protein interaction may underlie NAIC. By screening a yeast two‐hybrid cDNA library derived from human liver, and through affinity purification followed by mass spectrometry, we identified an uncharacterized nucleolar protein, NOL11, as an interaction partner for hUTP4/Cirhin. Co‐immunoprecipitation experiments show that NOL11 is a component of the nucleolar human ribosomal small subunit (SSU) processome. siRNA knockdown of NOL11 revealed that it is required to generate the mature 18S rRNA and for optimal rDNA transcription. Yeast two‐hybrid analysis shows that NOL11 interacts with the C‐terminus of hUTP4/Cirhin, and that the R565W mutation partially disrupts this interaction. Expression of the hUTP4/Cirhin R565W mutation only partially rescues the ribosome biogenesis defects, indicating that the disease mutation confers a defect in ribosome biogenesis. We have therefore identified NOL11 as a novel protein required for the nucleolar stages of ribosome biogenesis in humans. Our results further implicate a role for NOL11 in the pathogenesis of NAIC. Supported by NIH GM52581.
Stabilization of OCT4 by hypoxia mimetics, nickel and cobalt
Authors: Yao Yixin , Dai Wei
Published: June 2021

Stem cell research can lead to the development of treatments for a wide range of diseases including diabetes, heart disease, neurodegenerative diseases, aging, and cancer. OCT4 is an essential gene for the maintenance and expansion of stem cells. OCT4 also plays a primary role in reprogramming of somatic cells into induced pluripotent stem (iPS) cells. Given that hypoxia can enhance the generation of iPS cells, we examined expression of several stem cell factors in Tera‐1 cells that were exposed to nickel or cobalt, two well‐known hypoxia mimetic agents. Nickel treatment induced a concentration‐dependent increase in expression of OCT4 and HIF‐1a, but not SOX‐2, NANOG, c‐Myc and KLF4. Nickel‐induced OCT4 expression was due primarily to protein stabilization because MG132 alone or in combination with nickel increased OCT4 expression and because nickel did not significantly modulate the steady‐state mRNA level of OCT4. Nickel also stabilized OCT4 when new protein synthesis was inhibited by the treatment with cycloheximide. Moreover, cobalt treatment induced expression of OCT4 as well. Combined, these results indicate that enhanced expression of OCT4 under the hypoxic condition is mediated at least in part through protein stabilization. Our study also implicates that exposure to nickel and/or cobalt may affect stem cell proliferation and differentiation in vivo.
Recognition of the WXG Substrate YukE by the Type VII Secretion System in Bacillus subtilis
Authors: Sysoeva Tatyana A , Huppert Laura A , Ramsdell Talia L , Fortune Sarah M , Burton Briana M
Published: June 2021

Type VII protein secretion systems are crucial for the virulence of several human pathogens such as Mycobacterium tuberculosis and Staphylococcus aureus. However, the mechanism of secretion and the function of the secreted substrates are poorly understood. Type VII secretion systems were predicted to exist in numerous non‐pathogenic Gram‐positive organisms including Bacillus subtilis. It was recently demonstrated that the B. subtilis yuk operon encodes a functional Type VII secretion system that exports the small virulence factor homolog YukE. Each of the proteins encoded by the yuk operon is essential for YukE transport. Our study reveals that YukE undergoes unspecific, post‐secretion proteolysis. To address the substrate requirements for secretion and explore the role of the processing, we conducted mutational analysis of the YukE protein that belongs to the WXG protein family. The results show that conserved tryptophan and glycine residues are crucial for the recognition of this substrate by the secretory machinery. Intact C‐terminal residues are also important for efficient secretion of this WXG protein. These data reveal that recognition of the substrate in Yuk‐system in B. subtilis is similar to that of other Type VII secretion systems. These experiments open the possibility of using B. subtilis as a platform to investigate the core interactions between substrate and this novel secretion apparatus.
The crystal structure of human 15‐lipoxygenase‐2 in complex with a substrate mimic
Authors: Kobe Matthew James , Bartlett Sue G , Newcomer Marcia
Published: June 2021

Lipoxygenases (LOX) are a family of enzymes that produce, among other lipid mediators, eicosanoids capable of provoking and suppressing the inflammatory response. Atherosclerosis is associated with unchecked inflammation occurring over decades in humans. 15‐Lipoxygenase‐2 (15‐LOX‐2) is highly expressed in large, human atherosclerotic plaques. In order to gain insight into the catalytic activity of 15‐LOX‐2 and any role the enzyme or its products may play in plaque formation, we solved the crystal structure to 2.65 Å resolution. The structure revealed a detergent molecule bound in the active site that appears to bind as a substrate mimic. Kinetic experiments confirm that the detergent C8E4 competitively inhibits the enzyme. Unlike other LOX, the 15‐LOX‐2 structure has a long loop composed of nonpolar amino acids emanating from the polycystin‐1, lipoxygenase, alpha‐toxin (PLAT) domain. The PLAT domain loop is flanked by what appear to be two calcium‐binding sites, also found in human 5‐LOX. Förster resonance energy transfer (FRET) experiments indicate that Ca2+ induces membrane binding of 15‐LOX‐2 to Dansyl‐labeled liposomes. A comparison of human 15‐LOX‐2 and human 5‐LOX indicates significant differences in active site structures that can be exploited for isoform selective inhibitor design. The work was funded by a grant from the National Heart, Lung, and Blood Institute R01 (107887.)