bluuebunny/crossref_metadata_2025 huggingface dataset:
The cyclin dependent kinase, Cdk1, directly phosphorylates the vacuole‐specific myosin V receptor
Authors: Weisman Lois S , Peng Yutian
Published: June 2021

During cell division cytoplasmic organelles are actively distributed to the new daughter cells. This process is tightly controlled both spatially and temporally. In the yeast S. cerevisiae, the myosin V motor, Myo2p is required for the inheritance of several organelles. The itineraries of these organelles partially overlap, yet are not identical. Different cargoes bind to distinct regions within the cargo‐binding domain of Myo2. Moreover, organelle‐specific myosin V receptors attach cargoes to the motor. The existence of organelle‐specific receptors suggests that their regulation may account for the distinctive itineraries of each cargo. Indeed, regulation of the turnover of the vacuole specific receptor, Vac17, deposits the vacuole in its correct location. Here we report that regulation of Vac17 also controls the initiation of vacuole inheritance. The cyclin‐dependent kinase, Cdk1/Cdc28, directly phosphorylates Vac17. This phosphorylation enhances Myo2‐Vac17 interactions. Substitution of the Cdk1 sites in Vac17 results in both a delay and a defect in vacuole inheritance. These studies demonstrate that the key cell cycle regulator, Cdk1, plays a crucial role in the timing of vacuole movement. The fact that additional myosin V adaptors have multiple predicted Cdk1 sites suggests that the inheritance of other cytoplasmic organelles may be regulated by a similar mechanism.
Cellular communication in insulin secretion ex vivo and in vivo
Authors: Piston David W.
Published: June 2021

The islet of Langerhans is the functional unit responsible for glucose‐stimulated insulin secretion (GSIS), and thus plays a key role in blood glucose homeostasis. The importance of the islet is demonstrated by the proven ability of islet transplants to reverse Type I diabetes pathologies in human patients. Over the last 10 years, we have been interested in understanding the multicellular mechanisms of islet function, and their role in the regulation of blood glucose under normal and pathological conditions. In many ways, the islet appears to function as a syncytium, which exhibits synchronous behavior of membrane action potentials, Ca2+ oscillations, and pulsatile insulin secretion across all beta‐cells in the islet. In other ways, the islet works as individual cells, especially in the regulation of gene transcription. Using our unique quantitative optical imaging methods and novel microfluidic devices, the dynamics of these molecular mechanisms can be followed quantitatively in living cells within intact islets. These investigations utilize transgenic and tissue‐specific knock‐out mouse models with demonstrated phenotypes, as well as traditional biochemical and molecular biological approaches.
Cracking the Second Genetic Code
Authors: Hughes Tim
Published: June 2021

The interaction specificities between proteins and DNA has been termed the “second genetic code”. Despite the central importance of DNA‐binding activities to cell biology, physiology, development, and evolution, the complete binding activity of only a small minority of DNA‐binding proteins has been experimentally established. We have used microarrays to examine the binding specificities of over 300 mouse DNA‐binding proteins representing 23 different structural classes. Our results reveal a surprisingly complex landscape of DNA‐binding activities, with most proteins possessing unique and complex binding profiles, such that consensus and position weight matrix representations can have both low specificity and sensitivity. We propose that the evolutionary success of many DNA‐binding protein families, typically attributed to modularity in spatial expression or protein‐protein interactions, is also be due to diversity and malleability in DNA sequence recognition, which in turn could facilitate evolution of regulatory programs. We anticipate that the data resulting from this effort will be invaluable for understanding both gene regulation and genome evolution.
Will all Americans become overweight or obese? Obesity prevalence and health care cost projections
Authors: Wang Youfa , Beydoun May A. , Liang Lan , Caballero Benjamin , Kumanyika Shiriki K.
Published: June 2021

We project future prevalence and BMI distribution based on 1971‐2004 National Health and Nutrition Examination Survey (NHANES) data. Future obesity related health care costs for adults are estimated using projected prevalence, Census population projections, and published national estimates of per capita excess health care costs of obesity. Prevalence of overweight and obesity has increased steadily among all US groups, but notable differences exist among groups. Annual increase in obesity and overweight was faster in adults than children (0.77 vs 0.46–0.49 percentage point) and in women than men (0.91 vs 0.65). If the current trend continues, by 2030, 86.3% adults will be overweight or obese; and 51.1%, obese. Black women (96.9%) and Mexican American men (91.1%) would be the most affected. By 2048, all adults will become overweight or obese, while black women will reach that by 2034. In children, overweight prevalence (BMI≥95th, 30%) will double by 2030. Total health care costs attributable to obesity/overweight will double every decade to 860.7‐956.9 billion US$ by 2030, accounting for 16–18% of total US health care costs. In conclusion, we continue to move away from the Healthy People 2010 Goals. Projected increases will greatly increase public health burden and health care costs. Timely, dramatic and effective programs/policies are needed to avoid the otherwise inevitable health‐ and societal consequences.
Dietary supplementation of fish oil enriched with omega‐3 polyunsaturated fatty acids elevates seizure threshold in rats
Authors: Taha Ameer Y , Burnham W McIntyre , Bazinet Richard P
Published: June 2021

Epilepsy is a serious neurological disorder which is characterized by spontaneous, recurrent seizures. Simple partial seizures originating from the cortex are drug‐responsive, whereas complex‐partial seizures originating from the amygdala are drug‐resistant. Current anticonvulsant medications that are used to treat simple partial seizures have side effects including weight gain. Omega‐3 (n‐3) polyunsaturated fatty acids (PUFA) have been considered as a healthier alternative treatment for patients with epilepsy. Accordingly, we hypothesized that dietary supplementation of fish oil enriched with n‐3 PUFA would protect against epileptic‐like seizures originating from the cortex or amygdala, without altering body weight gain. Rats were surgically implanted with electrodes in the cortex or amygdala, and subsequently randomized to the AIN‐93G diet containing soybean oil or 40% fish oil for up to 34 weeks. Body weight gain, food intake and seizure thresholds were measured monthly. In contrast to soybean oil, fish oil supplementation elevated afterdischarge seizure threshold in the cortex (36%) and the amygdala (64%) relative to baseline (P<0.05). Fish oil treatment did not alter food intake and body weight gain over time (P>0.05). These findings indicate that n‐3 PUFA have anticonvulsant properties, and that they do not adversely affect body weight as seen with conventional anticonvulsant medications.
Relations of dietary type of protein, glutamine, and glutamate to the incidence of type 2 diabetes mellitus among middle‐aged women
Authors: Lenders Carine , HU Frank B , Willett Walter C , Douglas Wilmore W , Sampson Laura , Dougherty Lauren , Spiegelman Donna , Liu Simin
Published: June 2021

Objective: To examine the relations of types of protein, glutamine, and glutamate to the incidence of diabetes (T2DM) among middle‐aged women.

Methods: We identified incident cases of T2DM among 70,356 nurses free of T2DM and major chronic diseases at baseline, 1984–2002. Dietary habits were assessed using food frequency questionnaires. Cox proportional hazard models were used. Risk was considered significant at p for trend value<0.05.

Results: During the 18‐years follow‐up (1,115,620 person‐years), we documented 3,804 new cases of T2DM. After adjusting for demographic and lifestyle variables, T2DM was not associated with total protein RR=0.88[0.78;1.00], p =0.14), animal protein (RR=0.96[0.85;1.09], p=0.77), and glutamate (RR=0.88[0.77;1.00], p=0.10). Although plant protein was inversely associated with T2DM in the multivariate model (RR=0.88 [0.78;1.00], p=0.03), this relationship appeared to be explained by cereal fiber (RR=0.97[0.85;1.11], p=0.64).Glutamine was also inversely associated with T2DM in the multivariate model (RR=0.81[0.72;0.91], p<0.001). In further analysis, glutamine was inversely related to T2DM independent of cereal fiber (RR=0.87 [0.77;0.99], p=0.02) and total protein (RR=0.79 [0.69;0.90], p=0.0002).

Conclusions: Study findings suggest a significant modest inverse relation of glutamine with T2DM independent of total protein.
Go or Grow: How HA Controls the EGF Receptor
Authors: Schroeder Joyce Ann , Lopez Jose Ignacio , Louderbough Jeanne Vangils
Published: June 2021

The extracellular matrix (ECM) can govern epithelial cell behavior by influencing cellular invasion, a process which signals a deadly stage of cancer progression. In attempting to understand the role of the ECM in invasion, we previously found that the adhesion receptor CD44 protects against metastasis when cells are presented with hyaluronan (HA) embedded in Type I collagen. In our current studies, we have attempted to determine the mechanism by which CD44/HA interactions are inhibiting invasion. We have discovered that the inhibition of invasion provided by collagen‐embedded HA (eHA) occurs through the down‐regulation of both the Epidermal Growth Factor Receptor (EGFR) and PAK and corresponds with cell‐cell attachment and lamellopodia formation. Of significance is the observation that when HA is provided to cells in a soluble form (sHA), invasion is promoted and EGFR and PAK are both activated, corresponding to an inhibition of cell‐cell attachment and filopodia formation. Finally, we have found that these opposing effects of eHA versus sHA are further carried to the arena of proliferation, as eHA promotes proliferation and ERK MAP Kinase activity, while sHA inhibits each of these activities in the presence of collagen. Together, these data demonstrate that the form of HA presentation to the cell has a dramatic affect on its ability to alter cellular morphology, behavior and signal transduction events.
These spaces have great potential: teaching students about anatomical potential spaces.
Authors: Dalley Arthur F.
Published: June 2021

Potential anatomical spaces are vital to normal, pain free function of the heart, lungs, and locomotor system. They are also the basis for extraluminal endoscopic procedures. However, understanding potential spaces can be challenging. In dissection, potential spaces such as bursae and tendon sheaths are usually unnoticed. Others, such as the pleural and pericardial sacs, are viewed only after they have been opened, making them into realized spaces more representative of pathological states.

Difficult concepts include: (1) an “empty space,” containing only a capillary layer of lubricating fluid, (2) a structure being surrounded by (but not within) a potential space, (3) the ability of moist potential spaces to provide adherence and enable low‐friction movement at the same time, in the presence of positive or negative pressure, (4) parietal and visceral layers that are continuous layers of the same sac, and (5) the effect of actualization (interruption of surface tension), as in atelectasis.

Illustrations are helpful but require misleading exaggeration. Simple tools for better demonstrating concepts include large balloons, plastic bags, calculator paper, glass slides, “water wiggler” toys, and–for dissections–a syringe with injectable colored fluid.
The nerve plexus: Teaching students to detangle the mess.
Authors: LAMBERT H. Wayne
Published: June 2021

This anatomical presentation will give pedagogical tips to explain and categorize the complex network of intersecting nerve fibers called the nerve plexus. Nerve plexuses can be divided into spinal or autonomic nerve plexuses. Spinal nerve plexuses are a combination of adjacent anterior rami of spinal nerve, and they are named, usually, according to the vertebral level from which they originate. Autonomic nerve plexuses are composed of sympathetic, parasympathetic, and visceral sensory nerve fibers and they are associated with viscera and blood vessels. This presentation will conclude with an easy way to draw the brachial plexus, which is the spinal nerve plexus that most often introduces medical students to the concept of the nerve plexus.
Embryonic rotation of the stomach and midgut loop
Authors: OLSON TODD R.
Published: June 2021

The topography of the adult gastrointestinal tract and viscera together with the remodeling of their original mesenteric connections create some of the most vexing spatial relationship problems encountered in mastering the clinical anatomy of the human body. The complex, tortuous and, on first inspection, haphazard arrangement of the digestive tract is neither easily explained in text nor clearly elucidated with illustrations. Thirty years of personal experience teaching human embryology has demonstrated that when students attempt to follow the developmental succession of 90° and 180° rotations around the body's three axes their understanding often becomes more knotted‐up than straightened out. While animations greatly facilitate understanding, cognitive deficits persist for students who have difficulty visualizing and spatially integrating the chronology and final disposition of structures into their own body schema or image. All anatomists who teach in a dissection lab have witnessed many a student holding and maneuvering the heart or a bone against his or her own body until it is in the correct orientation. I believe this sensory‐motor learning process helps to personalize the location, orientation and relationships of structures within the student's own body. Through this kinesthetic and proprioceptive process, students gain a deeper appreciation for their own body and, consequently, an enhanced ability to mentally map anatomical structures in other bodies. Building upon this learning process, I have developed a didactic routine using a 15″ party balloon and 4′ rubber garden hose that permits students to observe and perform directly the rotations of the stomach and midgut loop.
Genes important for early development display promoter hypomethylation in zebrafish sperm
Authors: Cairns Bradley Robert , Zhang Haiying , Wu Shan‐Fu
Published: June 2021

Fertilization involves the joining of sperm and egg to form a pluripotent zygote. One key question for development is whether the promoters of genes important for pluripotency, or for guiding early development (transcription and signaling factors), bear chromatin marks or composition that facilitate their expression at the onset of zygotic transcription. As mature sperm are reported to be transcriptionally inactive and have much higher levels of DNA methylation than somatic cells (or eggs), it has been assumed that the sperm genome is essentially inert, is largely reprogrammed by the egg chromatin, and makes only a few unique contributions to development: the sex chromosome, paternal imprints and certain RNA molecules. To test the status of sperm chromatin, we performed genome‐wide DNA methylation profiling on zebrafish sperm and adult tissues. Surprisingly, although zebrafish sperm is globally hypermethylated, the promoters of many genes encoding important developmental transcription factors and signaling proteins are distinctly hypomethylated. This raises the interesting possibility that certain genes are poised in sperm by hypomethylation to assist in their expression in the developing embryo. Our current efforts to understand how DNA methylation levels are correlated with, and related to, histone modifications will also be presented.
X‐chromosome inactivation: Sex, heterochromatin, pairing, and noncoding RNA
Authors: Lee Jeannie T.
Published: June 2021

X‐chromosome inactivation (XCI) ensures that XY male and XX female mammals have equal X‐chromosome dosage. XCI takes place in both males and females. In females, one of two Xs is inactivated in the virtually all tissues of the soma. In males, both X and Y chromosomes become inactivated in the germline. One aspect of XCI that has particularly interested us is the fact that the somatic form depends on an X‐linked region (the ‘X‐inactivation center’) known for its abundance of long non‐coding transcripts. Working together, the three non‐coding elements, Xite, Tsix, and Xist, control the initiation of silencing along the entire X‐chromosome, resulting in the ‘coating’ of one X‐chromosome by Xist RNA and the recruitment of heterochromatic factors to that X in cis. While many steps of XCI are regulated in a cis‐limited fashion, XCI must in principle also be regulated in trans. Our recent work suggests that the two Xs communicate with each other in trans to ensure that the choice of active and inactive Xs occur in a mutually exclusive fashion. This trans‐communication apparently involves transient homologous pairing of the two Xs just prior to XCI. Pairing is absolutely essential and requires the non‐coding elements, Tsix and Xite. I will discuss our latest discoveries on the molecular aspects of these regulatory processes.
Nuclear Orphan Receptor COUP‐TFII in Reproduction
Authors: Tsai Sophia Y , Kurihara Isao , Lee Dong‐Kee , Qin Jun , Petit Fabrice , Takamoto Norio , DeMayo Francesco J , Tsai Ming J
Published: June 2021

COUP‐TFII (Chicken Ovalbumin Upstream Promoter‐Transcription Factor II) is an orphan nuclear receptor that belongs to the nuclear receptor superfamily. Genetic ablation of COUP‐TFII results in early embryonic lethality due to defects in angiogenesis and heart development. COUP‐TFII is expressed in the uterine stroma and is controlled by progesterone‐Ihh‐Ptch signaling. To assess the uterine function of COUP‐TFII, we have ablated COUP‐TFII in the uterine stroma by PR‐Cre. The uterine specific null mutants are infertile and exhibit defects in blastocyst attachment and decidualization. We identified a genetic pathway in which the epithelial Ihh regulates COUP‐TFII to control BMP‐2, which then regulates decidualization. Interestingly, enhanced epithelial estrogen activity, which impedes the maturation of a receptive uterus, was noted in the absence of COUP‐TFII. This finding reveals that COUP‐TFII mediates progesterone signaling to inhibit estrogen activity, and establishes the requirement for epithelia‐stromal interaction during the implantation process. COUP‐TFII is also expressed in the Leydig cells of male mice. Conditional ablation of COUP‐TFII in the male results in infertility due to impairment of spermatogenesis and Leydig cell differentiation. Taken together, COUP‐TFII is a critical player for female and male reproduction.

HL 076448, U54 H007495 PJ4, DK 62434
Metabolic Engineering of a Methanotroph for the Production of C40 Carotenoids for Aquaculture Applications
Authors: Sharpe Pamela Lorraine
Published: June 2021

Metabolic engineering of an obligate methanotroph, Methylomonas sp. 16a, for the production of high‐value carotenoids from methane or methanol has been accomplished. We have used genomic and genetic approaches to greatly accelerate the generation of high‐titer carotenoid‐producing strains derived from Methylomonas sp. 16a. This accomplishment demonstrates the ability to rapidly engineer non‐traditional microbial hosts and further indicates that globally available methane or methanol can serve as alternative feedstocks for bioprocesses. Methylomonas sp. 16a is a freshwater isolate classified on the basis of 16S rRNA analysis as well as biochemical traits. We have sequenced and annotated the Methylomonas genome, which has allowed unique insight into its metabolic capabilities. Metabolic engineering of Methylomonas has been used to produce various C40 carotenoids where high titers accumulate in the extensive intracytoplasmic membrane system. This work will show that it is possible to go from an environmental isolate, with no genetic system, to a metabolically engineered strain that meets production metrics in a short period of time via an interdisciplinary team of molecular biologists and engineers.
Long–term effects of caloric restriction on total and resting energy expenditure in healthy adults
Authors: Das Sai Krupa , Gilhooly Cheryl H , Golden Julie K , Pittas Anastassios G , Fuss Paul J , Dallal Gerard E , Saltzman Edward , Roberts Susan B
Published: June 2021

The effects of long‐term caloric restriction (CR) on resting metabolic rate (RMR) and total energy expenditure (TEE) in humans is uncertain. Objective To examine the effects of a 30% CR regimen on TEE and RMR. Methods One year randomized controlled trial of 30% CR in 29 healthy overweight adults (mean±SD, age 35±5y; BMI 27.5±1.5 kg/m2). All food was provided for 6 mo, and self‐administered for the next 6 mo. Outcomes included TEE, RMR, and body fat and fat free mass (FFM). Results Absolute values for RMR decreased during the intervention compared to baseline but measured RMR during CR was not significantly different from RMR predicted from body composition, and RMR changes over time assessed at 3, 6 and 12 mo were not statistically significant after accounting for decreases in body fat and FFM. TEE also decreased significantly with CR but at 12 mo there was a greater reduction in TEE than that anticipated due to the loss of FFM and fat mass (P=0.018). Conclusions This study found no evidence for long‐term metabolic adaptation to weight loss in assessments of RMR, but an adaptive reduction in TEE was observed, which may serve to protect the body against weight loss and contribute to weight regain.

Support: NIH grants: NGA‐3U01‐AG20480& #H150001; USDA No. 58‐1950‐4‐401.
Identification of genes differences between geriatric dogs with early indications of kidney disease compared to geriatric dogs without kidney disease
Authors: Frantz Nolan Z. , Yamka Ryan M. , Friesen Kim G. , Gao Xiangming , Al‐Murrani Samer
Published: June 2021

Forty geriatric (< 8 years of age) neutered/spayed beagles were identified for this study. Dogs were fed a control food for 30 days and then a blood sample was drawn into a PAXgene Blood RNA tube. RNA was extracted according to the procedures provided in the PAXgene Blood RNA Kit Handbook (Qiagen, Valencia, CA). RNA was hybridized to an Affymetrix GeneChip Canine‐2 Genome Arrays and normalized using Robust Multi‐Array Average. Transcripts having a P < 0.01 (following a false discovery rate adjustment value of 0.1) and a fold change range of at least 1.3 were considered different among the two groups. Analysis of the RNA found differences in 177 genes between the geriatric dogs with early indications of kidney disease and the normal group. Of the genes identified, 141 were up‐regulated and 36 down‐regulated in geriatric dogs with early indications of kidney disease when compared to normal geriatric dogs. Genes associated with inflammation and tissue remodeling were increased, while proper energy metabolism and hormone signaling were decreased in geriatric dogs with early indications of kidney disease compared to normal geriatric dogs.
Methylsulfonylmethane (MSM) Intake in Mice Produces Elevated Liver Glutathione and Partially Protects Against Carbon Tetrachloride‐Induced Liver Injury
Authors: DiSilvestro Robert A , DiSilvestro David J , DiSilvestro Daniel J
Published: June 2021

Methylsulfonylmethane (MSM) is a organic molecule present in small amounts in a number of foods and sold as a dietary supplement. MSM's antioxidant actions have been proposed based mostly on indirect evidence. For example, antioxidant actions in vivo of a related compound, DMSO, may be produced by MSM formed in vivo from DMSO. Thus, a study was done in mice to determine whether oral intake of MSM (OptiMSM®, Bergstrom Nutrition) could affect tissue levels of an internal sulfur‐containing antioxidant, glutathione, and resistance to chemically‐induced oxidant stress. MSM administration (5 weeks, 80 mg/100 ml drinking water) produced a statistically significant increase in liver glutathione (mean increase of 78%). A similar effect was not seen in lung or skeletal muscle. In addition, MSM partially inhibited liver injury after injection of carbon tetrachloride, which induces liver oxidant stress (injury evaluation based on blood indexes of hepatic injury). These results indicate the need for further testing for MSM antioxidant actions in vivo, and to explore the mechanism of elevated glutathione. This work was supported in part by an unrestricted research gift from Bergstrom Nutrition.
Growth and Body Composition of Human Milk‐Fed Premature Infants Provided with Extra Energy and Nutrients Early after Hospital Discharge: One Year Follow‐up
Authors: O'Connor Deborah Louise , Aimone Ashley , Ward Wendy , Vaughan Jennifer , Jefferies Ann , Campbell Douglas M , Asztalos Elizabeth , Feldman Mark , Rovet Joanne , Westall Carol , Whyte Hilary
Published: June 2021

The purpose of this pilot was to investigate the impact of early post‐hospital discharge supplementation of human milk with a multi‐nutrient fortifier on the growth and body composition of premature infants to one year corrected age (CA). Predominantly human milk‐fed infants (750–1800g birth weight) were randomized to an intervention (n=19) or control (n=20) group at discharge. Infants in the intervention received ~½ of their feedings supplemented with a multi‐nutrient fortifier (24kcal/fl oz, 22g protein/L plus other nutrients) for 12 weeks. Anthropometrics were determined at discharge and at 4, 6 and 12 months CA, and body composition at 4 and 12 months CA using dual energy x‐ray absorptiometry. Intervention infants were heavier, and longer at 12 months CA compared to control infants (p<0.005). Intervention infants born ≤ 1250 g had a larger mean head circumference throughout the first year of life (p=0.0002). Whole body bone mineral content at 4 and 12 months CA was greater in the intervention (p=0.02) but not when controlled for length. In conclusion, adding a multi‐nutrient fortifier to the milk provided to predominantly human milk‐fed premature infants early after discharge results in sustained differences weight, length, and in smaller babies, head circumference for the first year of life.

Funded by the Canadian Institute of Health Research(CIHR) and the CIHR Training Grant in Clinical Research
Does using MyPyramid in a community setting increase fruit and vegetable knowledge?
Authors: Chester Deirdra Nicole , Harris Ellen
Published: June 2021

The purpose of this study was to determine the extent to which using MyPyramid increased fruit and vegetable knowledge in a community setting. MyPyramid was presented at a health expo in the Washington, DC metropolitan area as a web‐based interactive nutrition challenge with a three‐staged test. Stage one (pre‐test) included five questions on classification of fruits and vegetables, amounts needed for optimal health, quantity to be consumed, cup equivalents, and important sources of nutrients. There was a significant improvement (p = .003, n = 92) between the pre‐ and post‐test (stage 3) scores (14.5 vs.16.1) related to fruit knowledge. Maryland residents (n = 42) scored significantly higher (p <0.05), as did women (n = 72), and those 51 years and older. Similarly, vegetable knowledge scores improved between the pre‐ and post‐tests (p=.007, n=71) (14.9 vs.16.6) with Maryland residents, women, non‐Hispanic whites, and the 31 – 50 year old age group significantly higher (p <.05). While significant improvements occurred when respondents were asked to correctly identify foods in the fruit group (p<.001) and in the percentage correctly identifying the amount of vegetables that should be consumed (p<.05), there were no significant differences between pre‐ and post‐test findings related to the more difficult questions defining MyPyramid cup equivalents and specific nutrients contributed by fruits and vegetables.
Total family time participating in WIC does not predict childhood overweight
Authors: Harrison Gail G. , Jenks Eloise , Afifi Abdelmonem , McGregor Samar , Whaley Shannon , Gomez Judy , Koleilat Maria
Published: June 2021

Increasing prevalence of overweight in young children is a significant public health problem. This study examines whether the total family time participating in the Special Supplemental Nutrition Program for Women, Infants and Children (WIC) plays a role in risk for early childhood overweight. We conducted a case‐control study with 555 WIC participant children ages 3–5 years who were either overweight (BMI >95th percentile of reference standard) or normal weight (BMI 25–75th percentile). The study population had a large Hispanic majority (95%), a group that has the highest rates of overweight young children in the US. Total cumulative history of WIC program participation for the entire family, expressed as person‐years and adjusted for reported breaks in participation, had a median of 12.6 person‐years and did not differ between overweight and normal‐weight children. In multivariate analyses only mother's BMI and child height were significant predictors of child overweight. Number of hours of television watching and number of hours of sleep at night showed slight but non‐significant relationships to overweight risk. There was no indication that cumulative family history of WIC participation influences risk of early childhood overweight. Supported by USDA/CSREES #2005‐35215‐16075.
Claudin‐5 decreases alveolar epithelial barrier function
Authors: Findley Mary Katherine , Ward Christina , Smith Tekla , Guidot David M. , Margulies Susan S. , Koval Michael H.
Published: June 2021

Chronic alcohol abuse increases lung epithelial permeability and impairs lung fluid balance. Patients with impaired alveolar fluid clearance are three times more likely to die from acute lung injury (ALI) or acute respiratory distress syndrome (ARDS). The extent of permeability between alveolar epithelial cells is carefully regulated by intercellular tight junctions. Transmembrane tight junction proteins known as claudins have distinctive distribution throughout various tissues including the lungs. Different claudins form paracellular ion channels with different permeability characteristics. We previously found that in the “alcoholic lung” several claudins, such as claudin‐7, are down regulated; however, claudin‐5 is upregulated. To test the effect of altering claudin expression on lung epithelial permeability, we transfected rat type II primary alveolar cells with different adenovirus claudin expression constructs. Barrier function of cells transfected with claudin‐4 or claudin‐7 is not significantly different than that of cells transfected with control adenovirus vector. However, cells transfected with claudin‐5 demonstrated a “leaky” phenotype. These cells showed increased paracellular flux of calcein and Texas Red Dextran and lower transepithelial electrical resistance (TER). This data suggests the increased claudin‐5 expression observed in the alcoholic lung could account for the observed increase in permeability. These findings are discussed in the context of current models, which suggest that the slow paracellular solute flux is regulated by either junction strand turnover or by pores that oscillate between open and closed conformations.
Oxidative Stress in Transgenic Mice with AZT Cardiomyopathy
Authors: Cucoranu Ioan Corneliu , Kohler James , Hosseini Seyed , Johnson David , Green Elgin , Hoying Amy , Russ Rodney , Fields Earl , Wittich Bree , He Stanley , Jones Dean , Lewis William
Published: June 2021

BACKGROUND

CM and myocarditis occur in HIV/AIDS and symptomatic heart failure is reported in up to 5% of HIV/AIDS patients. Highly active antiretroviral therapy (HAART) significantly reduced morbidity and mortality of AIDS, but has resulted in an increase in cardiac and skeletal myopathies. The thioredoxin (TRX) system is a ubiquitous thiol oxidoreductase system that regulates cellular reduction/oxidation status in the cytoplasm (Trx1) and in mitochondria (Trx2). To identify if oxidative stress is involved in cardiomyopathy induced by the HAART component Zidovudine (AZT) two TGs were employed. One TG exhibits down‐regulated cytosolic thioredoxin in the heart (Tg‐Trx1‐DN) the second TG exhibits overexpression of mitochondrial thioredoxin (Tg‐Trx2).

METHODS: TGs and WT littermates were treated with AZT (0.22 mg/day via gavage, n=7). After 35 d, left ventricle (LV) mass and left ventricle end diastolic dimension (LVEDD) were analyzed quantitatively by echocardiography (ECHO; 2D and M mode).

RESULTS: In WT, AZT significantly increased LV mass with a mild increase of LVEDD. Both treated and untreated Trx2 overexpressor TGs exhibited LV mass and LVEDD that resembled untreated WT, indicating protection from AZT CM. In contrast, Trx1‐DN mice exhibited baseline left ventricle hypertrophy which was decompensated to cardiac dysfunction with AZT therapy. There was minimal change in LVEDD.

CONCLUSIONS: Data suggests that AZT produces cardiomyopathy and oxidative stress is integral to development of AZT cardiomyopathy. Trx2 overexpression protects against AZT cardiomyopathy and Trx1‐DN mice demonstrate increased AZT sensitivity in the heart. Trx2 overexpressors and Trx1‐DN mice together may represent an important model of CM from AZT or oxidative stress.
Progress in deciphering the biological role of the human soluble epoxide hydrolase phosphatase activity
Authors: Morisseau Christophe , Aronov Pavel , Georgi Katrin , Ho Chin‐Min , Harris Todd , Hammock Bruce
Published: June 2021

The soluble epoxide hydrolase (sEH) is a unique enzyme in that it has two enzymatic activities on two separate domains: a C‐terminal epoxide hydrolase (Cterm‐EH), and a N‐terminal phosphatase (Nterm‐phos). The Cterm‐EH has been reported to hydrolyze epoxy‐fatty acids, especially epoxy‐eicosatrienoic acids (EETs) that are endogenous regulators of blood pressure and inflammation. Thus, Cterm‐EH inhibition is novel pharmacological approach to treat hypertension, pain and inflammation. The N‐terminal domain function is still not well known. It was thought to only help stabilize the C‐terminal domain. However, we recently described its magnesium dependent phosphatase activity on some lipid phosphates. We will report our progress on determining the substrate selectivity of the Nterm‐phos, as well as novel as specific inhibitors for this activity. The results will be discussed in light of possible interaction between the two domains, and biological roles of both sEH activities. This work was supported in part by NIEHS Grant R37 ES02710, NIEHS SBRP Grant P42 ES04699, and NIEHS CEHS Grant P30 ES05707.
Regulation of the soluble epoxide hydrolase by peroxynitrite
Authors: Barbosa‐Sicard Eduardo , Froemel Timo , Hammock Bruce D , Fleming Ingrid
Published: June 2021

Inhibition of the soluble epoxide hydrolase (sEH), which for example converts epoxyeicosatrienoic acids to dihydroxyeicosatrienoic acids (DHETs), has anti‐inflammatory as well as anti‐hypertensive effects. As the enzymatic core of the sEH hydrolase domain contains two tyrosine residues (Tyr383 & 466), we addressed the hypothesis that the activity of the sEH may be affected by oxidative stress, in particular by nitration of Tyr383 & 466.

sEH activity was measured in human and murine endothelial cells by LC‐MS/MS and was sensitive to the specific sEH inhibitor 1‐adamantyl‐3‐cyclohexylurea. The importance of the tyrosine residues was demonstrated in that mutation of Tyr383 & 466 to phenylalanine resulted in a complete loss of DHET production. sEH activity in both cell types was significantly (80±6%, P<0.001) attenuated by preincubation with the peroxynitrite (ONOO−) generator 3‐morpholino‐sydnonimine (SIN‐1, 0.5 mmol/L). The latter compound and authentic ONOO− also elicited the tyrosine nitration of the sEH (immunoprecipitation and Western blotting) an effect that was not be triggered by hydrogen peroxide (1 mmol/L). Moreover, in an in vivo murine model, oxidative stress induced by bacterial lipopolysaccharide significantly (20±9%, P<0.01) attenuated lung sEH activity. These data indicate that the activity of the sEH and thus cellular EET levels can be regulated by the tyrosine nitration of the protein.
The evolution of the C‐terminal domain of soluble epoxide hydrolase
Authors: Harris Todd R. , Aronov Pavel A. , Morisseau Christophe , Tanaka Hiromasa , Hammock Bruce D.
Published: June 2021

The mammalian soluble epoxide hydrolase is a multidomain enzyme composed of N‐ and C‐terminal regions that contain active sites for epoxide hydrolase and phosphatase activities, respectively. The spatial separation and differing homologies of the N‐ and C‐terminal domains have led to the hypothesis that the mammalian enzyme is the result of a gene fusion event between two ancestral genes. Although several plant and mammalian enzymes have been identified, little is known about sEH epoxide hydrolase activity in non‐mammalian animal systems. Analysis of genomic databases identified chicken, nematode and urchin sEH homologs which were subsequently cloned and expressed. The chicken and urchin enzymes contained both the N‐ and C‐terminal domains, while two nematode sEH homologs contained only the C‐terminal domain. All enzymes displayed sEH‐like epoxide hydrolase activity, which was described in terms of the ability to hydrolyze trans‐1,3‐diphenylpropene oxide and fatty acid epoxides such as the epoxyeicosatrienoic acids, and susceptibility to inhibition by urea‐based sEH inhibitors. The identification of sEH homologs with similar substrate selectivity as the mammalian enzyme suggests a conserved role for sEH epoxide hydrolase activity, perhaps involving the hydrolysis of epoxide lipid signaling molecules. This work has been supported by NIEHS Grant R37 ES02710 and NIEHS Grant P42 ES004699.
Arachidonic acid (AA) metabolism, systemic inflammation and cardiovascular disease (CVD) in patients with renal failure
Authors: Lu Ying , Schmelzer Kara , Hammock Bruce , Griffey Stephen , Troppmann Christoph , McVicarl John , Perez Richard
Published: June 2021

Patients with renal failure have a significant risk of CVD. AA metabolites are important in the regulation of inflammation and have been implicated in the pathogenesis of CVD. We explored the relationship between AA metabolism and CVD in this high risk population. Samples from 59 renal failure patients were obtained at the time of transplantation. Serum lipid metabolites involving pathways of cytochrome P450, soluble epoxy hydrolase, cyclooxygenase and lipoxygenase were analyzed by HPLC and inflammatory markers involving innate (neopterin) and adaptive (CD40 ligand) immunity were assessed by ELISA. A segment of inferior epigastric artery was assessed for CVD (intima proliferation and vascular calcifications). The frequency of CVD and vascular calcifications was 51% and 54%, respectively. Patients with vascular calcifications had elevated 14,15‐ and 11.12‐EET (1.8‐fold, p<0.05 and 3.7‐fold, p =0.09). Increased neopterin correlated with high 11,12‐EET and 6‐keto‐PGF1α. Elevated CD40 ligand correlated with 11,12‐EET, 14,15‐EET and 6‐keto‐PGF1α (table 1), as well as with intima proliferation (p=0.05) and vascular calcifications (p<0.05). The association of serum AA metabolites with systemic inflammation and CVD is consistent with a role of altered AA metabolism in the pathogenesis of CVD. This study was funded by an American Heart Association Grant.
Epoxy‐Fatty Amides and Esters as Substrates for Human sEH
Authors: Georgi Katrin , Morisseau Christophe , Huang Huazhang , Hammock Bruce D
Published: June 2021

The sEH has been reported to hydrolyze epoxy‐fatty acids, especially epoxy‐eicosatrienoic acids (EETs) that are endogenous regulators of blood pressure and inflammation. Thus, sEH inhibition is a novel pharmacological approach to treat hypertension, pain and inflammation. Lipid amides and esters represent another group of regulatory lipids. It is anticipated that epoxides of lipid amides may be biologically active. Thus, we examined the substrate selectivity of the soluble epoxide hydrolase with various lipid epoxides as free fatty acids and lipid amides. We found that sEH hydrolyzes natural amides and esters as well as free fatty acids, suggesting a role of this enzyme in endocannabinoid regulation. This work was supported in part by NIEHS Grant R37 ES02710, NIEHS SBRP Grant P42 ES04699, and NIEHS CEHS Grant P30 ES05707.
Inhibition of spontaneous colitis development in interleukin‐10 knockout mice by soluble epoxide hydrolase inhibitor
Authors: Yang Guang‐Yu , Zhang Meng , Chung Yeon Tae , Lou Chao , Tsai Cindy , Hammock Bruce D , Liao Jie
Published: June 2021

Inflammatory bowel disease (IBD) is a longstanding idiopathic inflammatory process and arachidonic acid metabolic pathway plays an important role in inflammatory cell recruitment and process. Epoxyeicosanoids acid (EET) has various physiological functions including anti‐inflammation effects, angiogenesis, and cell proliferation. EETs can be catalyzed to DHETs by soluble epoxide hydrolase (sEH) that deactivates EET biologic functions. Thus, targeting sEH would be novel approach for anti‐inflammation. In the present study, we tested the effects of sEH inhibitor AUDA‐nBE and 1471 agents on spontaneous colitis development in IL‐10 knockout mice. AUDA‐nBE was administered through intramuscular injection (10 and 20 mg/kg/day) and 1471 was given through drinking fluid (1.25 and 2.5 mg/kg/day). In IL‐10 KO control mice (n=10), colonic inflammation exhibited ulceration and transmural inflammatory cell infiltration in the right colon and number of ulcer formation was 2.3 ± 2.1. In the mice treated with AUDA‐nBE (n=10/group), significant reduction of ulcer formation was observed with number of ulcer 0.7 ± 0.9 for low dose and 0.4 ± 0.7 for high dose (p<0.01). Incidence of ulcer formation was also significantly inhibited (75% ulcer incidence vs. 50% and 30%, respectively, p<0.05). Similar results were also observed for mice treated with 1471 compound. Further mechanistic studies using immunohistochemical approaches showed that sEH inhibitor markedly suppressed macrophage activity and numbers, iNOS expression and its mediated nitrotyrosine formation in the colon. This study indicates that the sEH inhibitor may have a potential to serve as an anti‐IBD agent. (supported by NIH R01‐CA104741)
RNA virus infection affects the location and possibly the function of microsomal epoxide hydrolase
Authors: Duan Hongying , Kobayashi Nobuharu , Takagi Akira , Morisseau Christophe , Hammock Bruce D. , Akatsuka Toshitaka
Published: June 2021

We have reported that the autoantibody to microsomal epoxide hydrolase (mEH) is induced during the course of hepatitis C and hepatitis A virus infection (J. Autoimmunity 28:7, 2007). The appearance of mEH in sera during the incubation period and the virus specificity of the antibody response suggested that mEH is somehow affected by virus replication rather than by hepatocyte damage. In this study, we have elucidated the effects of RNA virus replication on the location and biochemical function of mEH in cell lines.

Human hepatocyte cell lines were infected with various RNA viruses or DNA viruses. They were also treated with poly (I:C) by adding to the medium or transfection. The mEH expression was analyzed by radioimmunoassay, immunofluorescence test, and western blotting. Metabolic activation of a carcinogen by these cells was evaluated by DMBA‐mediated cytotoxicity assay.

mEH was found to appear on the cell surface after infection with RNA virus but not with DNA viruses whereas the whole amount of mEH did not change significantly. Such changes could also be induced by poly (I:C) treatment The cells which displayed surface expression of mEH exhibited more than ten‐times higher sensitivity to DMBA‐mediated cytotoxicity.

These results suggest that RNA virus infection disrupts the distribution of mEH in the cells and affect the metabolic activation of polycyclic aromatic hydrocarbon carcinogens.
Expression pattern of microsomal and soluble epoxide hydrolase in mouse brain
Authors: Marowsky Anne , Arand Michael
Published: June 2021

Not much is known about expression and function of soluble (sEH) and microsomal (mEH) epoxide hydrolase in the brain. In rat brain sEH expression is only detectable in small quantities under normal conditions with a marked increase in spontaneously hypertensive rats. mEH expression is found around Alzheimer plaques and in epileptic and tumor brain tissue in humans and rats, suggesting a lesion‐induced upregulation. We used immunohistochemistry and Western blots to investigate the distribution pattern of the two enzymes in adult mouse brain. Interestingly, the cellular distribution is almost complementary with the sEH exclusively expressed in glia cells of the fore brain while the mEH is found in specific subtypes of neurons, endothelial cells of cerebral vessels and in cells of the choroid plexus. The mEH is particularly abundant in CA3 pyramidal cells of the hippocampus, striatal and central amygdalar neurons and granule cells of the cerebellum. In addition, motor neurons in the brain stem express mEH. While mEH expression in the choroid plexus is in line with the role of the enzyme in detoxification, the neuronal expression pattern implicates an additional function perhaps in signal transmission. sEH expression in astrocytes is consistent with the postulated function of the enzyme in local blood flow regulation.
Differential subcellular distribution and colocalization of microsomal and soluble epoxide hydrolases in rat cortical astrocytes.
Authors: Shivachar Amruthesh C. , Rawal Seema , Morisseau Christophe , Hammock Bruce D.
Published: June 2021

The purpose of this study was to determine the expression, localization and subcellular distribution of microsomal (mEH) and soluble (sEH) epoxide hydrolases in cultured rat cortical astrocytes. Cultures of astrocytes were probed for mEH and sEH by immunocytochemistry, immunoblotting and enzymatic assays. Our results showed immunofluorescence for mEH and sEH, which colocalized with the astroglial cytoskeletal marker, glial fibrillary acidic protein (GFAP). Western blotting analyses for mEH revealed a protein band of molecular mass ∼50 kDa, the intensity of which was increased about 1.5‐fold, especially in the microsomal fraction. Whereas the polyclonal sEH rabbit serum recognized a protein band of molecular mass ∼62 kDa, which increased 2.0 fold in the 105,000xg supernatant over the cell lysate. The sEH rabbit serum also recognized similar protein bands in mitochondrial and nuclear fractions. The enzymatic analyses, using mEH‐ and sEH‐selective substrates further corroborated these findings. Our results suggest that astroglial cells, by expressing both mEH and sEH, may play a role in the cerebrovascular functions affected by epoxides (Funding Support: G12RR03045‐17 (ACS) and R37ES02710 (BDH)).