bluuebunny/crossref_metadata_2025 huggingface dataset:
The Effect of Spatial Ability on Speed and Accuracy of Identifying Anatomical Structures (344.3)
Authors: Palmer Phillip , Colburn Chelsi , Holland Amanda , Ooten Savannah , Robertson Lawrence
Published: June 2021

We examined the effect of spatial ability (SA) on accuracy and efficiency in identifying anatomical structures. Thirty‐three undergraduate students with majors in biology, nursing, exercise science, and psychology participated in the study. Students with previous exposure to cadavers and persons with sensitivity to formaldehyde were excluded. Participants completed two tests of SA; the Santa Barbara Solids and the Visualization of Views Tests. Subjects were assigned to high (HiSA) and low (LoSA) groups based on their scores. The participants were then asked to identify structures highlighted on a two‐dimensional image by placing numbered pins on a prosection. Participants were timed, but were not aware of this. On completion, the accuracy of pin placement was determined by two researchers. MANCOVA was utilized to assess the effect of SA on accuracy and speed of identification of structures. Previous experience in a human anatomy course (non‐dissection) was used as a covariate. This variable did not have a significant effect on students' performances. SA, however, was found to have a significant effect. Univariate tests were calculated to determine which of the two variables was affected by SA. The results indicated that the HiSA group scored higher (p = 0.22) on identification with a mean score of 9.39 (CI95, 8.64, 10.13) as compared to the LoSA group with a mean score of 8.07 (CI95, 7.25, 8.89). There was no significant difference between groups on the time required to complete the task (p = 0.726). The findings suggest that students with higher spatial abilities are better at using two‐dimensional images to recognize anatomical structures. Determination of SA may help in identifying students with LoSA and altering instruction to enhance their learning.
Using Geometric Morphometrics to Examine Cranial Disparity in Extinct and Extant Marsupial and Placental Carnivores
Authors: Borths Matthew , Corbin Kate
Published: June 2021

Carnivory evolved independently in multiple mammalian lineages including Carnivora, Dasyuramorphia, and extinct Borhyaenidae, Oxyaenida and Hyaenodontida. Each lineage combines expanded attachment sites for mandibular adductors with specialized shearing dentition. Three‐dimensional geometric morphometrics were used to characterize cranial disparity in each carnivorous lineage to test for a correlation between developmental constraint in the marsupial carnivore skull and the limited morphological diversity of the group. When only extant Carnivora is included in the analysis, marsupial carnivores do occupy a separate, limited region of morphospace. When a large sample of extinct placental carnivores are included, placental morphospace and marsupial morphospace overlap. Placental Hyaenodontida, which shares with marsupial carnivores the presence of multiple carnassialized molars, unreduced dentition, long rostra, and distal temporomandibular joints, overlap extensively with marsupial carnivores. Hyaenodontidans dominated carnivore niches during early Paleogene, but were replaced by carnivorans. This analysis demonstrates the anatomical similarities between hyaenodontidans and marsupial mammals may be more significant factors in the extinction of both carnivorous lineages rather than developmental constraints affecting the cranial and functional diversity of marsupials.
Neural Stem/Progenitor Cells of the Spinal Cord are Activated in Response to Tail Loss in the Leopard Gecko
Authors: Gilbert Emily , Vickaryous Matthew
Published: June 2021

As for many lizards, the leopard gecko (Eublepharis macularius) is able to self‐detach its tail as an anti‐predation strategy and subsequently regenerate a replacement. The replacement tail includes a regenerated spinal cord. We hypothesize that endogenous neural stem progenitor cells (NSPCs) are present in the original spinal cord and that these cells are activated during regeneration. As many stem cells are slow cycling, we used a Bromodeoxyuridine (BrdU) pulse‐chase experiment to identify label‐retaining populations in the original spinal cord. We also conducted a spatiotemporal characterization of spinal cord cells before and during regeneration using a panel of common NSPC markers (including Sox2, Sox9, Vimentin, βIII‐Tubulin and Musashi‐1, and the proliferation marker PCNA). BrdU retaining cells were still present after a 20‐week chase. Prior to injury, expression of NSPC markers is limited, but co‐localization of BrdU and Sox2 in ependymal cells was observed. Following tail loss, ependymal cells in the original stump of the tail become highly proliferative and express our panel of NSPC markers. Outgrowth of the new tail is matched by proliferating, NSPC marker‐positive ependymal cells. These cells appear to contribute to regenerating spinal cord. We conclude that ependymal cells are a likely source of endogenous NSPCs in the gecko and that they are activated following tail loss.

NSERC Grant: 400358
The Role of the Eda Pathway in the Morphogenesis of Molar Roots
Authors: Star Haza , Tucker Abigail
Published: June 2021

The role of the Eda gene during the formation of ectodermal appendages such as nail, hair, teeth, and sweat glands have been unveiled through many studies. Mutation in the Eda pathway (Eda, Edar, Edaradd) results in Hypohydrotic Ectodermal Dysplasia (HED) with patients showing hypodontia and abnormally shaped teeth. The role of the Eda pathway in tooth crown development has been widely studied using the mouse as a model but the role of the Eda pathway during root formation is not well known. I have used computerised tomography (CT) and histological sections of Eda ‐/‐ (tabby) and Edar ‐/‐ (downless) mice to investigate possible root defects in these mice.

My analysis shows a clear variation in the size, shape, and number of roots in mutants (tabby and downless) compared to wild type littermates. In particular the mutant teeth showed late or no bifurcation of roots (Taurodontism), indicating disruption in the development of the cells that create the roots (Hertwig epithelial root sheath, HERS). In situ analysis also indicated that Shh expression was reduced in these cells. The results show that the Eda pathway has a role in root morphogenesis and we are now further investigating the mechanisms by which loss of the Eda pathway affects root formation.
Students' personality and learning anatomy
Authors: Finn Gabrielle , Carter Madeline , Smith Claire
Published: June 2021

There is increasing recognition within education of the importance of non‐cognitive factors, including personality, for performance. This talk will look at data from both the qualitative and quantitative paradigms in order to consider the relationship between personality and performance within anatomy assessments. Particular consideration will be given to the personality domain of conscientiousness, which is a well‐established predictor of performance in both workplace and academic settings. Data from quantitative studies investigating the relationships between the 'Big Five' personality domains, the facets of conscientiousness and performance in a practical anatomy examination will be presented. These studies found that performance in an anatomy examination was related to higher levels of conscientiousness and, more specifically, to higher levels of achievement striving. Additionally, qualitative data exploring how students construct their anatomical knowledge and, the interplay between this and their personality, will be presented. The results of these studies have important implications for selection and assessment in medicine.
Timing the Developmental Origins of Mammalian Limb Diversity
Authors: Sears Karen , Maier Jennifer , Behringer Richard , Cretekos Chris , Rasweiler John , Zhong Sheng , Rapti Zoi
Published: June 2021

From bat wings to whale flippers, the evolution of diverse limb forms has enabled mammals to infiltrate almost every habitat. We seek to determine the developmental processes that have been modified to produce new limb forms, and the degree to which the nature of these processes predisposes the evolution of some limb forms instead of others. To pursue these goals we quantified the transcriptome and morphology of developing bat, mouse, pig and opossum limbs. Results suggest that limb outgrowth is initially conserved and then diverges, consistent with earliest limb outgrowth being developmentally constrained. To test this hypothesis we built and perturbed gene interaction networks for early (EN) and late limb development, and found that the EN is more robust. We then quantified levels of the same genes within populations and among species, and found that they vary less at earlier developmental stages. These results suggest that EN robustness buffers population‐level variation in gene expression early in limb development, and constrains the evolution of early limb development among species.
Role of chaperones in healthy bowel and IBD
Authors: Cappello Francesco , Tomasello Giovanni , Rappa Francesca , Farina Felicia , Zummo Giovanni , Conway de Macario Everly , Macario Alberto
Published: June 2021

The chaperoning system is the whole complement of chaperones, co‐chaperones and chaperone co‐factors of the body that preserves cell and tissue homeostasis. Its structural and/or functional defects can cause pathologic conditions, named chaperonopathies. Large bowel homeostasis includes a healthy status of the mucosal tissues and the microbiota. An alteration of one of them may detemine, in turn, modifications of the other. Molecular chaperones of bacteria and human origin have been implicated in inflammatory bowel disease (IBD). In IBD chaperone levels usually increase and their cellular and subcellular localization change. This is considered a physiological stress‐response of mucosal cells to inflammation. However, chaperones also play active roles in IBD pathogenesis, e.g. perpetuate inflammation. Therefore, IBD can be classified among the chaperonopathies. This classification opens the door to the design and application of new forms of treatement targeting the chaperones, namely chaperonotherapy.
Skeletal kinematics reveal the complex interactions of degrees of freedom at joints
Authors: Kambic Robert
Published: June 2021

Measuring range of motion (ROM) is a common technique for investigating the relationship between morphology and function at joints in both extant and extinct taxa. ROM studies often present results as tables or graphs of minimum and maximum joint angles; however, joint motion is a complex three‐dimensional interaction among multiple degrees of freedom. Using X‐ray Reconstruction of Moving Morphology, I present results from experiments that directly measure three rotational degree of freedom kinematics in birds. Every pose achieved at a joint is plotted in angle‐angle‐angle space for the three possible degrees of freedom, producing a ROM envelope. The results demonstrate that degrees of freedom interact in complex ways that cannot be summarized as mere minima and maxima. Two and three degree of freedom joints produce irregular two‐dimensional surfaces and three‐dimensional volumes. Plotting in vivo poses within these ROM envelopes demonstrates that the ROM of certain degrees of freedom may be overestimated, but that living animals were willing to push joints farther than the researchers in other cases. These results demonstrate that soft tissues and bone interact in complex ways to guide joint motion.

The NSF, the W.M. Keck Foundation, and the Bushnell Research and Education Fund supported this work.
Solutions for gigantism: evolutionary and biomechanical implications of dinosaur hip joint soft tissues
Authors: Tsai Henry , Middleton Kevin , Holliday Casey
Published: June 2021

Reconstructing joint anatomy and function is critical to understanding locomotor behavior, ecology, and evolution of vertebrates. Dinosaurs evolved a wide diversity of hip joint morphology and locomotor postures, as well as seven orders of magnitude in body size. Sauropods and theropods independently, iteratively evolved large body size, and used large volumes of soft tissues to maintain hip joint articulation. This study tested the relationships among hip joint dimensions, morphological characters, and body mass of dinosaurs. Femora and pelves of 140 taxa were studied and digitized using 3D imaging techniques. Discrete and continuous characters were analyzed using phylogenetically corrected correlation to reveal trends in body size evolution. Theropods and sauropods independently reduced bony congruence of the hip joint, such that the thick femoral chondroepiphysis and acetabular pads maintain articulation. However, both transitions in soft tissue morphology preceded evolution of gigantism. Differential distribution of fibro‐ and hyaline cartilages suggests that the sauropod hip joint is built to sustain heavy compressive loads, whereas those of theropods experienced both compression and shear. These data indicate that the dinosaur hip joint underwent divergent transformations in soft tissue morphology, joint loading, and postures during the convergent evolution of gigantism.
Proteolytic Remodeling of the 3D Extracellular Matrix Controls the Nuclear Regulation of Mesenchymal Stem Cell Fate and Function
Authors: Weiss Stephen
Published: June 2021

In vitro, topographical and biophysical cues arising from the extracellular matrix (ECM) direct mesenchymal stem cell (MSC) commitment and differentiation. While the mechanisms by which the MSC‐ECM interface is regulated and the outcome of such interactions on stem cell fate in vivo remains largely unexplored, we recently demonstrated that the membrane‐anchored metalloproteinase, MT1‐MMP (Mmp14), directs MSC fate decisions, including osteogenesis as well as adipo‐ and chondro‐genesis. By effecting ECM remodeling, MT1‐MMP regulates stem cell shape, thereby activating a β1 integrin/RhoGTPase signaling cascade and triggering the nuclear localization of the transcriptional coactivators, YAP and TAZ, that serve to control MSC lineage commitment. Furthermore, we find that MT1‐MMP‐mediated proteolysis of the ECM additionally, but unexpectedly, controls nuclear architecture, chromatin remodeling and RNA transcription via a process dependent on the linker of nucleoskeleton and cytoskeleton (LINC) complex. These data identify a critical MT1‐MMP/nuclear axis operative in the 3D stem cell niche that oversees MSC fate determination.
Metabolism and Actions of N‐Acylethanolamines in Seedling Development
Authors: Chapman Kent , Keereetaweep Jantana , Blancaflor Elison
Published: June 2021

N‐Acylethanolamines NAEs are fatty acid derivatives linked to ethanolamine via an amide bond. In seeds of most plants including Arabidopsis thaliana, NAEs with linolenic (18:3) and linoleic (18:2) acids together make up more than 70% of the total NAE pool, and they both decline precipitously to pmol/g‐fr‐wt levels with the progression of seed germination and seedling development. Elevated, exogenous levels of these polyunsaturated NAEs applied within a few days of post‐germinative growth restrict normal seedling establishment with NAE18:2 manifesting marked inhibition of root development and NAE18:3 interfering most conspicuously with normal cotyledon development. Seedling sensitivity to growth inhibition by polyunsaturated NAEs overlaps with the well‐known secondary dormancy stage induced by abscisic acid (ABA) that is believed to support survival from stresses during seedling establishment. Biochemical, genetic and pharmacological evidence indicates that both NAE types can be metabolized by specific lipoxygenase (LOX) isoforms during the course of seedling establishment, leading to a complex array of NAE oxylipin metabolites. Specific ethanolamide oxylipins of the NAEs appear to be attributed to tissue‐specific inhibitory action, and suggest these molecules may participate in the coordinate control of seedling establishment under unfavorable environmental conditions in cooperation with phytohormone and light signaling pathways.
Using Comparative Metabolomics to Target Cancer
Authors: Griffin Jules
Published: June 2021

Because of the complexities and diversity of metabolites, no one analytical approach can cover the whole metabolome. We have been using a range of analytical platforms based around a combination of NMR spectroscopy and mass spectrometry to maximise the coverage of the metabolome and then map these changes onto other datasets such as MRI images, transcriptomics and proteomics using multivariate statistics in order to build up a profile of tumour cell metabolism. Such data fusion based approaches provide increased mechanistic insight into the development of cancer. I will present examples from: (i) apoptosis in glioma associated with the accumulation of polyunsaturated fatty acids, (ii) proliferation and aggressiveness in breast cancer characterised by increased turnover in newly synthesized phosphatidylcholines and (iii) the development of non‐genotoxic carcinogenicity in liver tissue associated with alterations in eicosanoid metabolism. In particular, I will focus on how cell proliferation and apoptosis is associated with key changes in lipid metabolism, helping us understand the metabolic changes detectable by magnetic resonance spectroscopy and providing a mechanistic framework for some of the in vivo biomarker associated with tumour detection and treatment.
Rescuing Cell Polarity with Small Molecule Inhibitors of De‐Palmitoylation
Authors: Martin Brent
Published: June 2021

Protein palmitoylation is a unique post‐translational modification required for the membrane anchoring and trafficking of numerous regulatory proteins that play key roles in cell growth, polarity, and signaling. In pulse‐chase palmitoylation proteomics studies, we identified the subset of epithelial tumor suppressors as enzymatically regulated palmitoylated proteins in malignant cells. One such protein, Scribble, localizes at the basolateral membrane where it regulates epithelial cell apical‐basolateral polarity, junctional integrity, proliferation, and metastasis. Loss of Scribble at the plasma membrane cooperates with oncogenic Ras or Myc overexpression to drive tumor formation, promote epidermal to mesenchymal transition (EMT), and bypass contact inhibition. Interestingly, overexpression of Snail in polarized cells eliminates Scribble membrane localization. We recently reported a class of in vivo active small selective inhibitors of the acyl protein thioesterases APT1 and APT2. Addition of a small molecule APT2 inhibitor restores Scribble membrane localization and enhances E‐Cadherin expression, overcoming Snail‐mediated repression. Using a combination of x‐ray crystal structures, medicinal chemistry, and mass spectrometry, we present a broadened understanding of thioesterase function and inhibition in cells. These findings highlight APT2 as a primary regulator of cell polarity protein palmitoylation, and highlight a strategy to attenuate oncogenic signaling and restore cell polarity pathways in malignant cells.
Disorder in Protein Switches
Authors: Gsponer Jörg
Published: June 2021

Interactions of intrinsically disordered (ID) protein segments with partner proteins are often mediated by molecular recognition features (MoRFs). MoRFs in ID segments are not only used in interactions in trans but also in cis, i.e., they can mediate interactions between an ID segment and a domain that are both part of the same polypeptide chain. Such interactions in cis can switch the function of a protein domain off by steric or allosteric inhibition of substrate or binding partner access to catalytic sites or binding surfaces, respectively. This phenomenon is called autoinhibition. We demonstrate that most cis‐regulatory elements in proteins are ID and that the MoRFs in these ID autoinhibitory regions are highly conserved. We present results from molecular dynamics simulations that reveal the mechanism by which phosphorylation of MoRFs can relieve autoinhibition and introduce the first predictor that identifies ID autoinhibitory regions in proteins from sequence information only.
Prebiotics Impact Fecal Microbiota and Gut Physiology in Diet‐Induced Obese Mice
Authors: Liu Tzu‐Wen , Holscher Hannah , Cephas Kimberly , Kerr Katherine , Mangian Heather , Tappenden Kelly , Swanson Kelly
Published: June 2021

Obesity is associated with compromised intestinal barrier function and shifts in microbiota that may contribute to inflammation. Previous research suggests benefits of supplemental fiber, but the impacts of fermentable vs. non‐fermentable fibers are not well understood.

OBJECTIVE

To determine the impact of cellulose vs. fructan (short‐chain fructooligosaccharides [scFOS] or inulin) supplementation on fecal microbiota and gut physiology in obese mice.

METHODS

18‐wk old C57BL/6J mice (n=6/group) were fed high‐fat diets (45% kcal fat) containing 5% cellulose, 10% cellulose, 10% scFOS or 10% inulin for 4‐wk. Cecum and distal colon were collected to assess barrier function, histomorphology and gene expression. Fecal DNA was extracted, followed by 16S rRNA amplicon Illumina MiSeq sequencing and analysis with QIIME 1.8.0.

RESULTS

Both fructans increased (p<0.05) intestinal transmural resistance and crypt depth but reduced (p<0.05) mRNA abundance of ZO‐1 and occludin. Principal coordinates analysis (PCoA) of weighted and unweighted UniFrac distances of fecal microbiota revealed a sharp separation (p<0.05) between fructan and cellulose groups. Alpha diversity measures revealed lower (p<0.05) species richness with fructan supplementation. Fructans reduced (p<0.05) the relative abundance of Firmicutes and increased (p<0.05) Actinobacteria and Verrucomicrobia (Akkermansia).

CONCLUSION

Fructan supplementation may modulate gut microbiota and physiological responses via multiple mechanisms.
Hepatic Oxylipin Profiles in Obese Rats: Effect of Antioxidant Supplementation
Authors: Picklo Matthew , Newman John
Published: June 2021

Obesity induces biochemical changes in lipid metabolism. The extent to which enzymatic and non‐enzymatic lipid (per)oxidation products, oxylipins, are altered by obesity is of great interest. Conflicting data exist regarding oxidative damage to lipids in obesity. We investigated the extent to which antioxidants altered hepatic oxylipin profiles in the context of obesity in order to define pathways sensitive to obesity vs antioxidants. Obese‐prone rats (4 wks old) were fed either a control, low‐fat diet (LF; 10% en from fat), a high‐fat diet (HF, 45% en from fat), or a high‐fat diet with supplemented vitamin C and vitamin E (HF‐CE) for 16 wks. Animals fed the high‐fat diet with and without antioxidants accrued more fat tissue than the LF animals and were insulin resistant. Analysis of hepatic oxylipins demonstrated distinct effects resulting from obesity versus antioxidant supplementation. Measures of oxidative damage to lipids, F2‐isoprostanes and 9‐hydroxyeicosatetraenoate (9‐HETE), were not elevated by obesity, but were reduced by antioxidant supplementation. Similar results were observed with the lipoxygenase products, Lipoxin A4, 8,15‐dihydroxyETE, and 5,15‐dihydroxyETE. Conversely, obesity, with and without antioxidant supplementation, increased epoxy products of linoleic and alpha‐linolenic acids, derived through cytochrome P450 (CYP450), activity while causing a decrease in the resulting dihydroxy epoxide hydrolase metabolites. These data indicate that (1) oxidative damage to hepatic lipids is not an absolute corollary of obesity, (2) antioxidant supplementation can decrease lipoxygenase pathway activity, and (3) obesity modifies hepatic CYP450‐mediated fatty acid metabolism.
Thrombospondin‐1 Regulates Hepatic Lipid and Energy Metabolism to Increase Carcinogenesis in an In Vivo Model of Colorectal Cancer
Authors: Emenaker Nancy , Soto Pantoja David , Snipes Michael , Morris Niccole , Roberts David
Published: June 2021

We interrogated biochemical profiles in murine liver tissue from wild type, thrombospondin‐1 (TSP) null, ApcMin/+ and ApcMin/+TSP‐/‐mice to identify metabolic changes accompanying tumorigenesis arising from varied dietary lipid intakes in these colon cancer models. We found high‐fat diets trigger hepatic accumulation of medium‐ and long‐chain saturated, monounsaturated, and polyunsaturated free fatty acids compared to low‐fat diets. While elevations in free fatty acids were similar across groups, select medium‐chain free fatty acids were elevated in ApcMin/+:TSP‐/‐ mice. ApcMin/+:TSP‐/‐ animals fed a high‐fat diet that displayed unique metabolic changes including ketone body 3‐hydroxybutyrate levels and numerous TCA cycle intermediates in the high‐fat ApcMin/+:TSP‐/‐ group, findings that are typically suggestive of decreased TCA cycle activity and oxidative phosphorylation due to mitochondrial dysfunction. We suggest one explanation for the cumulative differential changes observed in ApcMin/+:TSP‐/‐ mice fed a high‐fat diet may involve mitochondrial dysfunction, resulting in decreased fatty acid oxidation and ketone body formation and the accumulation of free fatty acids. This metabolic profile suggests that the increase in adenoma formation in ApcMin/+/TSP‐/‐ knockout animals may be due in part to mitochondrial dysfunction elicited by the consumption of a high fat diet.
Synergistic Effects of Fiber and Phytochemicals in Wheat Bran on Colon Cancer
Authors: McBride Jennifer , Zhu Yingdong , Wang Pei , Sang Shengmin
Published: June 2021

Colorectal cancer (CRC) is a leading cause of cancer related deaths in the United States. Epidemiological studies have suggested that dietary factors play an important role in the development of CRC. Many studies support the hypothesis that dietary fiber, especially from cereal sources, protects against CRC. The AICR/WCRF Second Expert Report upgraded the evidence for an inverse association between dietary fiber intake and CRC risk from “probably” to “convincing”. Although most studies show a correlation between whole grain (WG) consumption and reduction of the risk of CRC, the active components in WGs have not been fully explored. Most of the mechanisms proposed are based on the physiological function of fiber. Short‐chain fatty acids especially butyrate, which are the fermentation products of wheat bran (WB) fiber by gut microbiota in the colon, have been proposed to be protective agents. We and others have found that lipid‐soluble phytochemicals, especially alkylresorcinols (ARs) are the active components in WB for colon cancer prevention. From a whole foods viewpoint, it is critical to understand the interaction between different bioactive food components. Therefore, we studied whether sodium butyrate (NaB), the microbial derived metabolite of WB fiber, and ARs, the bioactive phytochemicals in WB, have additive/synergistic effects against the growth of human colon cancer cells. Our results indicated that NaB and AR C21 had synergistic effects against the growth of human colon cancer cells (HCT‐116 and HT‐29). Further mechanistic studies found that the levels of apoptosis were higher in combinations than in the individual compounds via activating the mitochondrial apoptotic pathway.
A Plasma Proteome Associated with Inflammation in Nepalese School‐aged Children
Authors: Lee Sun Eun , West Keith , Cole Robert , Schulze Kerry , Yager James , Groopman John , Christian Parul
Published: June 2021

Micronutrient status may be influenced by inflammation, however, it is typically characterized by only C‐reactive protein (CRP) or alpha‐1‐acid glycoprotein (AGP) in nutrition studies. We applied quantitative proteomics to explore plasma proteins that co‐vary with inflammation, reflected by AGP in 500 children 6‐8 yr of age in rural Nepal where elevated AGP was common. Among 982 proteins, 41 and 58 proteins were positively and negatively associated with AGP, respectively, passing a false discovery rate threshold of 0.001%. Positively associated proteins included major positive acute phase proteins including CRP, complement components, protease inhibitors, transport proteins with anti‐oxidative activity, and intracellular signaling molecules. Negatively associated proteins showed a distinct pattern in the abundance profile, characterized by tissue origin: proteins of hepatic origin included plasma transporters for lipids, micronutrients (vitamin A and calcium), growth factors and sex hormones, while extra‐hepatic proteins included structural components of extracellular matrix (ECM) or regulators of ECM metabolism. Our findings reveal a vast number of plasma proteins associated with AGP that reflect active homeostasis of the host defense systems, metabolism of nutrients and other biomolecules, and tissue repair processes. Using population data, we provide evidence of a “plasma inflammasome”, reflecting proteomic dynamics of inflammation, as an extended list of potential candidates for inflammation biomarkers.

This study was funded by Bill and Melinda Gates Foundation (OPP5241 and GH614).
Prospective Study of Vitamin B2 Intake and Colorectal Cancer
Authors: Cho Eunyoung , Yoon Yeongsook , Jung Seungyoun , Zhang Xuehong , Giovannucci Edward
Published: June 2021

Background

Despite the involvement of vitamin B2 to regulate the one‐carbon metabolism and the immune system, only few prospective cohort studies have examined the association between vitamin B2 intake and colorectal cancer (CRC) reporting inconsistent results.

Objective

To examine the association between vitamin B2 intake and risk of CRC and to evaluate if the association varies by alcohol consumption and folate intake.

Design

Among 105,628 women and 44,527 men followed up to 2010 in the Nurses' Health Study and Health Professionals Follow‐Up Study, 3,285 cases of incident CRC were identified (2,359 women and 926 men). Vitamin B2 intake was measured by a validated food frequency questionnaire administered every 4 years during follow‐up. To estimate the association between vitamin B2 intake and CRC, Cox proportional hazard models were used to calculate the relative risks (RRs) and its 95% confidence intervals (CIs).

Results

Vitamin B2 intake was associated with a borderline reduced risk of CRC among women (Ptrend = 0.03), but not among men (>Ptrend = 0.73). The multivariate RRs (95% CI) for individuals in the highest quintile of total vitamin B2 intake (from food and supplements) compared to those in the lowest quintile were 0.89 (0.77‐1.03) in women and 0.98 (0.77‐1.23) in men. The associations were similar when stratified by alcohol consumption and folate intake.

Conclusions

Our results suggest no strong association between high vitamin B2 intake and the risk of CRC.

Source of research support : This work was supported by research grants CA136950, CA87969, and CA167552 from the National Institutes of Health.
Ambient fine particulate matter induces endothelial progenitor cells apoptosis via reactive oxygen species formation
Authors: Cui Yuqi , Xie Xiaoyun , Jia Fengpeng , He Jianfeng , Li Zhihong , Fu Minghuan , Hao Hong , Liu Ying , Liu Jason , Cowan Peter , Zhu Hua , Sun Qinghua , Liu Zhenguo
Published: June 2021

Background/Aims

Bone marrow (BM)‐derived endothelial progenitor cells (EPCs) play a critical role in the angiogenesis. Some environmental insults, like fine particulate matter (PM) exposure, significantly inhibit EPCs‐mediated functions. However, the mechanisms remain largely unknown. The present research was to study the detrimental effects of PMon EPCs and explore the potential mechanisms.

Methods

PMwas intranasal‐distilled into male C57BL/6 mice for one month. Flow cytometry was used to measure the total number, apoptosis of circulating EPCs and intracellular reactive oxygen species (ROS) formation. Serum TNF‐ α and IL‐1β were measured using ELISA. To determine the role of PM‐induced ROS in EPC apoptosis, PMwas co‐administrated with the antioxidant N‐acetylcysteine (NAC) in wild type mice or used in a triple transgenic mouse line (TG) with overexpression of antioxidant enzyme network (AON) composed of superoxide dismutase (SOD)1, SOD3, and glutathione peroxidase (Gpx‐1) with decreased in vivo ROS production.

Results

PM treatment significantly decreased circulating EPC population, promoted apoptosis of EPCs in association with increased ROS production and serum TNF‐α and IL‐1β levels, which could be effectively reversed by either NAC treatment or overexpression of AON.

Conclusion

PM exposure significantly decreased circulating EPCs population due to increased apoptosis via ROS formation in mice.

Funding sources: NIH R01 HL094650; AHA 12SDG12070174
Early Radiation‐Induced Secretion of Gastrin‐Releasing Peptide (GRP) Mediates Late Pulmonary Fibrosis
Authors: Sunday Mary , Heck Karissa , Komforti Miglena , Tighe Robert , Toomey Christopher , Zhou Shutang
Published: June 2021

Pulmonary fibrosis (PF), a devastating disease affecting >105 Americans, can have environmental, autoimmune, or idiopathic causes. In lung, pulmonary neuroendocrine cells secrete GRP in response to oxidant exposures. Previously, we showed early GRP elevation precedes PF in hyperoxic baboons. Also, GRP blockade given to mice twice weekly abrogates radiation (RT)‐induced pulmonary fibrosis at 20 wks. We have now tested the hypothesis that early GRP secretion mediates PF by using a C57L/J mouse model of RT‐induced PF, with prolonged, irreversible kinetics like human PF. 1‐24h post‐RT mice were injected IP with PBS, 2A11 (GRP‐blocking mAb), or 77427 (GRP‐blocking small molecule). Sham controls were not irradiated. Urine was collected every 6h for 24h pre‐ and post‐RT. Lung tissue sections 10‐15 weeks post‐RT were stained for collagen (Masson's trichrome), elastin (Hall's method), and α‐smooth muscle actin immunostaining (SMA, myofibroblast marker). Quantitative image analysis was performed on alveolar photomicrographs by blinded observers. Mice had tenfold‐elevated urine GRP levels 0‐6h post‐RT, which declined to 2‐fold elevated at 18‐24h, abrogated by GRP blockade 1h post‐RT. Multiplex analysis of lungs at 24h showed only IL‐10 elevation, prevented by GRP blockade 1h post‐RT. One dose of GRP blockade 24h post‐RT abolished parameters of PF 15‐wks later: increased interstitial collagen, elastin, and myofibroblasts. In conclusion, urine GRP is elevated before 24h post‐RT, prevented by GRP blockade, which also blocks pathological hallmarks of PF months later. GRP is a novel biomarker for PF and GRP blockade might prevent PF and its sequelae.
Proteomic Profiling of Histone Posttranslational Modifications in Late Gestation Fetal Hepatocytes Capable of Liver Repopulation
Authors: Francois‐Vaughan Heather , Doud Emma , Thomas Paul , Kelleher Neil , Gruppuso Philip , Sanders Jennifer
Published: June 2021

Hepatocyte transplantation has the potential to be an effective therapy for acute liver disease and metabolic disorders. Our laboratory has focused on late gestation (E19) liver development in the rodent. We have identified a fetal hepatocyte phenotype defined by differences in signaling pathways and gene expression. We recently found that E19 hepatocytes expressing the hepatic marker leucine aminopeptidase (LAP) have the ability to repopulate an injured adult liver. Our current studies are based on the hypothesis that histone posttranslational modifications (PTMs) acting through effects on chromatin structure account for the E19 hepatocyte signaling phenotype and the repopulating ability of these cells. We employed a bottom‐up mass spectrometry based approach to profile PTMs on histone H3 and H4 in freshly isolated LAP+ E19 hepatocytes and adult hepatocytes, and cultured adult hepatocytes. In order to mimic the asynchronously proliferating E19 hepatocytes, adult hepatocytes were cultured in the presence of EGF and insulin for time points ranging from 0 to 72 hr and combined into pooled samples for mass spectrometry. We identified significant differences in 10 of the 26 histone PTMs on H3 and H4 comparing the asynchronously proliferating LAP+ E19 and cultured adult hepatocytes. In summary, late gestation fetal hepatocytes capable of liver repopulation possess a histone PTM profile that is distinct from that of adult hepatocytes.
Attenuation of the Inflammatory Response After Acetaminophen‐Induced Injury by Human Mesenchymal Stem Cell‐Derived Hepatocytes in Mice
Authors: Stock Peggy , Brückner Sandra , Winkler Sandra , Dollinger Matthias , Christ Bruno
Published: June 2021

Mesenchymal stem cells from human bone marrow (hMSC) have the potential to differentiate into hepatocyte‐like cells in vitro and continue to maintain important hepatocyte functions in vivo after transplantation into host mouse livers. Here, hMSC were differentiated to hepatocyte‐like cells in vitro (hMSC‐HC) and transplanted into livers of immunodeficient Pfp/Rag2‐/‐ mice treated with a sublethal dose of acetaminophen (APAP) to induce acute liver injury. APAP induced a time‐ and dose‐dependent damage of perivenous areas of the liver lobule. Serum levels of AST increased to similar levels irrespective of hMSC‐HC were transplanted or not. Yet, hMSC‐HC were found in the damaged perivenous areas of the liver lobules short‐term preventing apoptosis and thus gross destruction of the organ. Disturbance of metabolic and secretory protein expression was lower in the livers receiving hMSC‐HC. 7 weeks after APAP treatment, hepatic injury had completely recovered in groups both, with or without hMSC‐HC. Clusters of transplanted cells appeared predominantly in the periportal portion of the liver lobule and secreted human albumin featuring a prominent quality of differentiated hepatocytes. Thus, hMSC‐HC attenuated the inflammatory response and supported liver regeneration after acute injury induced by acetaminophen. They hence may serve as a novel source of hepatocyte‐like cells suitable for cell therapy of acute liver diseases.
A Cytochrome P450‐independent Mechanism of Acetaminophen‐induced Hepatocellular Injury
Authors: Miyakawa Kazuhisa , Albee Ryan , Letzig Lynda , Lehner Andreas , Scott Michael , Buchweitz John , James Laura , Ganey Patricia , Roth Robert
Published: June 2021

Acetaminophen (APAP) hepatotoxicity in mice resembles in most ways that which occurs in humans. Primary mouse hepatic parenchymal cells (HPCs) are the most frequently used cell type in vitro to study mechanisms of APAP hepatotoxicity. It is widely accepted that APAP hepatotoxicity requires bioactivation by cytochromes P450 (CYPs), but this remains unproven in HPCs over the wide range of concentrations that have been used in published reports. Accordingly, we tested the hypothesis that APAP‐induced HPC death in vitro depends solely on CYPs. We evaluated APAP cytotoxicity and bioactivation (formation of APAP‐protein adducts) in the presence and absence of the CYP inhibitor 1‐aminobenzotriazole (1‐ABT). 1‐ABT abolished formation of APAP‐protein adducts at all concentrations tested (0.1‐14mM) but only eliminated cytotoxicity at small APAP concentrations (0.1‐5mM), indicating the presence of a CYP‐independent mechanism at larger concentrations. The APAP deacetylation product, p‐aminophenol (PAP), was detected in HPCs exposed to a large APAP concentration, and a deacetylase inhibitor significantly reduced cytotoxicity. In conclusion, APAP hepatocellular injury in vitro occurs by at least two mechanisms, a CYP‐dependent mechanism that operates at smaller APAP concentrations and a CYP‐independent mechanism that predominates at larger concentrations and is later in onset. PAP likely contributes to the latter mechanism. (Supported by NIH grant R01 DK087886)
Evaluating anti‐β‐Catenin monoclonal antibodies for cancer diagnosis and prognosis
Authors: Lu Hsiangmin Emily , Fu Wei , Yuan Kehu , Chu Boyang , Wang Guangli , Shu Youmin , He Weiwu , Ma Donghui
Published: June 2021

Colorectal cancer is one of the most common cancers and ranks second in mortality in the US. Wnt/β‐Catenin signaling pathway plays an important role in colorectal cancer, and the mutation events have been studied the most for colorectal carcinogenesis. However, other studies have shown the nuclear translocation of β‐Catenin could be an additional factor for clinical diagnosis of colorectal cancer. Therefore, it is essential to develop the monoclonal antibody with the highest sensitivity and specificity. Even though there are many monoclonal antibodies being used for β‐Catenin studies, they have not been carefully examined for potential cross‐reactivity which could cause false diagnosis.

To develop the most suitable monoclonal antibody for β‐Catenin studies, we used different immunoassays to validate the specificity and sensitivity of the commercially available antibodies. By the high density protein microarray chip technology and other assays, we identified that β‐Catenin UltraMAB antibody can be used for different applications in basic research. Furthermore, we used immunohistochemistry with tissues from colorectal cancer patients and showed that β‐CateninUltraMAB antibody is a great tool for potential cancer diagnosis and prognosis.
Functional Role of MicroRNA‐200 Family in Human Gall Bladder Cancer Stem Cells
Authors: Meng Fanyin , Francis Heather , Han Yuyan , Glaser Shannon , Alpini Gianfranco
Published: June 2021

BACKGROUND & AIMS

MicroRNAs (miRNAs) are highly conserved 19‐25 nucleotide noncoding small RNAs which are primarily involved in gene silencing. Our aim was to characterize the functional roles of epigenetic regulated microRNAs in human gall bladder cancer stem cells.

METHODS

miRNA expression in human gall bladder cancer tissues, human gall bladder cancer stem cells (GB‐CSCs), Mz‐ChA‐1 gall bladder cancer cells and H69 non‐malignant cholangiocytes was assessed using a hybridization based microarray and was further evaluated by Taqman real‐time PCR analysis. Promoter methylation, matrix metalloproteinase (MMP) 1, 2, 3 and 9 mRNA expression was quantitated by real‐time PCR analysis.

RESULTS

We identified miR‐200 family including miR‐200a, miR‐200b and miR‐200c that are differentially expressed in doxorubicin‐enriched cell fractions in a mouse xenograft tumor model of gall bladder cancer. Expression of miR‐200 family microRNAs was substantially enhanced concomitant with GBCs differentiation and loss of self‐renewal. Methylation‐specific PCR detected that miR‐200b and miR‐200c promoter was hypermethylated in GB‐CSCs, GBCs as well as Mz‐ChA‐1 cells. Cell migration and invasion were significantly decreased by miR‐200 precursor introduction in GB‐CSCs and Mz‐ChA‐1 cells. Bioinformatics and dual‐luciferase reporter assays identified ZEB1 and ZEB2 as the direct targets of miR‐200 family.

CONCLUSION

Our results define a novel epigenetic regulatory mechanism of specific microRNA group and suggesting that miR‐200 cluster may be the molecular targets for eradication of human gall bladder cancer.
Intercellular Adhesion Molecule 1 (ICAM‐1) Regulates Cardiac Remodeling and Function in Pressure Overload Induced Heart Failure
Authors: Salvador Ane Miren , Nevers Tania , Aronovitz Mark , Blanton Robert , Alcaide Pilar
Published: June 2021

Left ventricular (LV) dysfunction and Heart Failure (HF) are associated in humans with systemic inflammation and elevated serum levels of intercellular cell adhesion molecule‐1 (ICAM‐1). ICAM‐1 regulates leukocyte recruitment into tissues, a process that in the heart can result in altered cardiac function. We hypothesized that endothelial ICAM‐1 regulates cardiac remodeling by controlling leukocyte recruitment to the heart. We used the mouse model of Thoracic Aortic Constriction (TAC) to induce cardiac remodeling and HF, combined with immunohistochemistry, flow cytometry, qPCR, echocardiography and hemodynamics. TAC induced up‐regulation of LV ICAM‐1 and LV T cell infiltration in WT mice. In contrast, CD3+ and CD4+ T cell recruitment into the LV was similar between ICAM‐1‐/‐ TAC and Sham mice. In response to TAC the systolic and diastolic functions were preserved in ICAM‐1‐/‐ mice, whereas LV weight, cardiomyocyte size, and mRNA expression of the hypertrophic markers ANP and BNP were decreased as compared to WT mice. In addition, TAC did not induce LV fibrosis or up‐regulation of the fibrotic markers Collagen‐I, TGFβ and SMAα in ICAM‐1‐/‐ mice. Our studies indicate that ICAM‐1 regulates LV T cell infiltration, cardiac function and fibrosis in HF induced by TAC. Further studies will determine the contribution of ICAM‐1 to HF pathogenesis via mediating T cell‐cardiac endothelium interactions or directly regulating cardiac cell function.
MuRF2 attenuates the severity of high‐fat diet‐induced diabetic cardiomyopathy by regulating cardiac PPAR‐γ
Authors: He Jun , Quintana Megan , Sullivan Jenyth , Han Yipin , Willis Monte
Published: June 2021

Metabolic changes of diabetic cardiomyopathy are regulated by PPAR family nuclear receptors. Mice lacking the Muscle Ring Finger‐2 (MuRF2‐/‐) E3 have increased cardiac PPAR‐α PPARβ/δ, and PPAR‐γ activity in vivo. We hypothesized that challenging MuRF2‐/‐ mice with a high‐fat diet (HFD) would enhance diabetic cardiomyopathy due to increased cardiac PPAR activity. MuRF2‐/‐ mice and were challenged with a 60% HFD for 26 weeks and cardiac function was followed by conscious echocardiography. Serial serum glucose and insulin measurements were obtained and PPAR activity followed by qPCR of PPAR‐regulated genes. We identified that MuRF2‐/‐ mice exhibited significant decreases in function by 6 weeks of HFD challenge (FS% 40.73% vs. MuRF2+/+ 54.60%, P<0.05). MuRF2‐/‐ mice exhibited significantly increased insulin at 26 weeks HFD compared to baseline (4.86 vs. 3.55 ng/ml, P<0.05). Surrogate measures of PPAR‐γ activity were enhanced (MuRF2‐/‐ CD36 mRNA 18.20 fold vs wildtype 12.73 fold, P<0.001). Mechanistically, we identified that MuRF2 inhibited PPAR‐γ1 protein expression in a stoichiometric manner. HEK293 cells co‐transfected with HA‐MuRF2 and p3xFlag‐PPAR‐γ1 plasmids in increasing ratios of MuRF2/PPAR‐γ1 were treated with Rosiglitazone (a PPAR‐γ agonist) and PPAR‐γ1 analyzed western blot. PPAR‐γ1 protein levels were significantly decreased at the MuRF2/PPAR‐γ1 protein ratios of 4, 5, and 10. These studies demonstrate that ligand‐dependent MuRF2 degradation of PPAR‐γ1 may be a contributor to inhibiting PPAR‐γ activity in vivo and the development of diabetic cardiomyopathy.
T Cells Control Cardiac Remodeling in Pressure Overload Induced Heart Failure
Authors: Nevers Tania , Salvador Ane , Grodecki‐Pena Anna , Knapp Andrew , Velazquez Francisco , Aronovitz Mark , Kershaw Tanya , Blanton Robert , Kapur Navin , Karas Richard , Alcaide Pilar
Published: June 2021

Patients with heart failure (HF) have increased activation of pro‐inflammatory cytokines in their circulation, and the mechanisms associated with this increase are still unknown. Recent studies have suggested T cells as an important cellular source for this observed systemic inflammation and immune activation in chronic HF. Thus, we hypothesize that T cells are major players influencing cardiac remodeling and contributing to the pathogenesis of pressure overload induced HF. We observe by immunohistochemistry analysis that T cells infiltrated the left ventricle (LV) of the heart in patients with end stage HF compared with subjects without HF. Additionally, systemic T cells from patients with advanced HF adhered to activated human umbilical vein endothelial cells (HUVECs) in higher numbers than T cells from healthy donors under flow conditions. To study this phenomenon further, we utilized the mouse model of thoracic aortic constriction (TAC) in wild type (WT) and T cell deficient (TCRα‐/‐) mice to mimic pressure overload induced HF. We found that in WT mice, T cells can also infiltrate into the left ventricle (LV) and this was associated with worsening cardiac function. Conversely, TCRα‐/‐ mice subjected to TAC had improved cardiac functions as determined by echocardiographic and hemodynamic evaluations, reduced fibrosis and LV hypertrophy, and improved survival compared to WT TAC mice. Thus, our studies indicate that T cell mediated immune responses and their recruitment into the heart

influence cardiac remodeling and inhibiting T cell activation may be a potential therapeutic strategy to improve the deficits of the failing heart.