bluuebunny/crossref_metadata_2025_split huggingface dataset:
Emersion Profiles and Recovery: Quantifying Physiological Responses in Mussels
Authors: Dilly Geoff Fowler , Brazier Garrick David , Christensen Katherine Mary , Moran Randy William 
Published: November 2023

Rocky intertidal zones are in a constant state of flux. Sessile intertidal organisms must tolerate a suite of dynamic abiotic conditions: temperature, wave action, pH, hypoxia, and most dramatically, emersion. The duration of emersion also changes daily depending on the tides; additionally, air temperatures shift with diurnal cycles, seasonal differences, and weather conditions. Thus, the West Coast mussel, Mytilus californianus (M.c.), a key indicator species of intertidal community health, must tolerate rapid shifts between a wide variety of submerged and emerged conditional regimes. Previous literature on M.c. stress responses to conditional shifts have focused primarily on respirometric rates during immersion experiments and/or protein turnover with relation to emersion. Our full‐factorial study combines these approaches to explore the respirometric responses of M.c. to emersion at a range of environmentally relevant thermal regimes (air: 7, 18, and 35°C; water: 14 and 24°C), emersion durations (4 and 8 hour), and recovery times (0 and 30 minute) using a custom‐designed respirometry system.To conduct in vivo respirometry experiments, we built a new customizable isolation system named the Chambers for Organismal Response to Environmental Stressors (CORES) to interface with a NeoFox spectrophotometer (Ocean Optics, Dunedin, Fl). This low‐cost, novel system allows for continual non‐invasive measurements of dissolved oxygen on a variety of marine invertebrates. Mytilus californianus were collected from Ventura, California (34.272° N, −119.287° W) and acclimated at temperature in lab aquaria. After 2‐hour respirometric trials, gills were excised and divided evenly for dry‐weight respirometric calculations and RNA extractions. We quantify key gene expression stress responses using RT‐qPCR with HSP70, HSC71 (thermal), catalase (oxidative), phosphofructokinase (metabolic), and caspase (apoptosis) on a CFX96 RT‐PCR System (Bio Rad, Hercules, CA).Calculated respiration rates were positively correlated with water temperature and emersion duration, indicating that Mytilus californianus needed to regenerate their depleted aerobic capacity after exposure to these stresses. Additionally, our data suggest M.c. maintained at 24°C experience a stress‐induced state of torpor following 8‐hour periods of emersion at boundary air temperatures (7 and 35°C). A differential response in respiration rate was observed at the median air temperature of 18°C, indicating that air temperatures at the boundaries of environmental conditions increase the time of recovery to homeostasis after mussels are re‐submerged.Support or Funding InformationThis work is supported by CSU Channel Islands and an NSF I‐Corps CSUPERB sub‐award.
Development of a Patient‐Based Computational Modeling Framework for Analyzing the Mechanisms of Doxorubicin Cardiotoxicity
Authors: Lewalle Alexandre , Land Sander , Niederer Steven 
Published: November 2023

Doxorubicin, a potent anticancer drug, has well known dose‐dependent cardiotoxic side effects. In particular, doxorubicin exposure disrupts protein expression and impacts multiple biochemical pathways through the generation of reactive oxide species and oxidative stress, which in turn leads to cardiomyopathy and congestive heart failure. Specific effects of doxorubicin exposure at the biochemical, cellular, and tissue levels, have been extensively studied. However, a systematic quantitative assessment of the relative significance of these effects on the separate subsystems of the heart, in the perspective of overall cardiac function, remains to be done. Gaining such an understanding of the mechanisms underlying heart failure is essential for the development of diagnoses and treatments.Computational modeling provides a unique platform for exploring cardiac function in silico and gaining insight into the interplay between its separate mechanistic contributions, within the context of doxorubicin cardiotoxicity. We therefore developed a multi‐scale computational modeling framework to simulate the heart contraction cycle. The model was designed to be sufficiently detailed to include the main known aspects of cardiac muscle behavior, while retaining enough simplicity to enable its parameterization using clinical and experimental data. This approach provides a “virtual workbench” for simulating cardiac function with maximal objectivity and faithfulness with regard to measurements derived from patients.The model parameters were constrained using available data (echocardiography, cuff pressure, biopsy‐based proteomics analyses) derived from either doxorubicin‐treated or “control” cohorts. The flexibility of the model allows the determination of the sensitivities of the main cardiac phenotypes to specific parameters, in both cohorts. We thus aimed to identify the predominant pathway for the onset of doxorubicin cardiotoxicity, as characterized by a substantial lowering of the left‐ventricular ejection fraction (LVEF).Our results suggest that a structural remodeling of the heart (e.g., a widening of the left‐ventricular diameter) contributes partially to the decrease in LVEF. Additional necessary contributions must include changes to the passive or active contractile properties of the heart tissue. By using available proteomics analyses derived from patient biopsies, we aim to discern quantitatively between these contributions, resulting from cumulative doxorubicin exposure.Support or Funding InformationThis study is supported and funded as part of the European Commission HeCaTos Project (Hepatic and Cardiax Toxicity Systems modeling), Proposal 602156‐2.
MicroRNA Profile of Excised Cutaneous Squamous Cell Carcinoma Tissues Comparative to Adjacent Normal Tissue
Authors: Pulford Christopher S. , Loomis Ellise M. , Montgomery McKale R. , Uppalapati Chandana K. , Pascual Agnes S. , Hull Elizabeth E. , Leyva Kathryn J. 
Published: November 2023

Cutaneous Squamous Cell Carcinoma (cSCC) is the second most common form of skin cancer commonly arising from sun‐induced mutations. As most cases of cSCC are treated by tumor excision, research aimed at understanding factors influencing the metastasis, and possible alternative treatments, of cSCC is limited. Cancer metastasis is a multistep process, including epithelial‐to‐mesenchymal transition (EMT). During EMT, epithelial cells undergo a dedifferentiation process whereby they transition to a highly mobile and invasive mesenchymal cell type with metastatic capacities. Although the factors influencing EMT are varied, one important mediator of intercellular communication shown to be involved in oncogenesis is miRNA. Our work focuses on miRNAs, which are small non‐coding RNA species that may be one epigenetic factor contributing to the progression of cSCC. In this study, we compared the expression pattern of seven miRNAs (miR‐21, ‐31, ‐34a, ‐125b, ‐199a, ‐204, and ‐1246) between fresh primary tumor samples and fresh adjacent normal tissue (ANT) collected from patients diagnosed with either cSCC, SCC in situ, or invasive SCC. Total RNA was isolated from each of the samples and qPCR on all samples was performed to determine the expression level of each miRNA relative to control. Of the seven miRNA tested, two were significantly upregulated (miR‐21 and miR‐31) in the patient SCC samples compared to ANT. As many of these miRNAs are predicted to target genes involved in EMT in other cancers, we have begun examining the expression of known EMT markers via qPCR and/or Western blot from RNA and protein isolated from both SCC and ANT tissues. Preliminary results indicate that mRNA expression of TGFβ1 is significantly increased and mRNA expression of E‐cadherin is significantly reduced in cSCC relative to normal tissue, indicative of a progression of EMT in the cancerous tissue. Other EMT markers are being examined as well. Further work investigating the function of these differentially‐expressed miRNAs will help to begin elucidating the role miRNAs are playing in the progression of cSCC.Support or Funding InformationBiomedical Sciences Program and MWU Intramural Funds
Effects of Ketogenic Diet in Young Adult and Old Rats
Authors: Duplisea Michael J. J. , Wilson Esther K. , Cheung Eric C.K. , Parker Brian A. , Carr Sheryl T. , Ashby Conrad K. , Bikman Benjamin T. , Thomson David M. 
Published: November 2023

Ketogenic diets (KD) have been promoted extensively for weight loss and health. However, their effects in aged skeletal muscle are not well‐defined. In this study, we tested the effect of a ketogenic diet in young adult (YA; 5 month old) and old (O; 28 month old) male Fisher 344 rats (n = 4–6/group). Rats were assigned to either standard chow (STD; Evigo Teklad Rodent Diet, 8604; 32% protein, 14% fat, 54% carbohydrate) or ketogenic diet (KETO; Envigo Teklad Custom Diet, TD.10911; 22.4% protein, 77.1% fat, 0.5% carbohydrate) for 4 weeks, and weighed weekly. KETO rats were pair fed isocalorically with STD chow rats within each age group with the YA rats eating 0.132 kcal/g body weigh/day, and O rats eating 0.109 kcal/g body weight/day. After 24 or 25 days glucose tolerance testing was performed by fasting the rats for 6 hours followed by an injection of 1 mg glucose/g BW. Blood glucose concentration was measured from tail blood immediately before and 15, 30, 60 and 120 minutes after the glucose injection. Ketones were also measured from tail blood immediately before the glucose injection. After the 4‐week treatment period, rats were euthanized and gastrocnemius muscle was collected for determination of mitochondrial respiration and AMP‐activated protein kinase (AMPK; an important stimulator of glucose and fatty acid metabolism) phosphorylation. We found that KETO feeding increased blood ketone levels, albeit non‐significantly (p=0.065), in YA but not O rats. KETO resulted in significant weight loss within 2 weeks in both YA and O rats. Glucose tolerance was impaired in O‐STD vs. YA‐STD rats, while KETO impaired glucose tolerance in YA, but not O rats. KETO increased mitochondrial respiration in YA, but not O rats. AMPK phosphorylation was decreased by KETO vs. STD diet in YA, but not O rats. We conclude that a KETO diet induces a significant drop in body weight and enhanced mitochondrial respiration, but impaired glucose tolerance in YA rats, suggesting a shift from glycolytic to oxidative metabolism. Somewhat surprisingly, these KETO‐induced changes in YA rats are associated with decreased AMPK activation. O rats are resistant to all of these effects of KETO diet except for weight loss, suggesting impaired metabolic plasticity with old age. Further study will be required to elucidate the exact molecular pathways underlying these shifts.Support or Funding InformationThis research was supported by Brigham Young University Mentoring Environment Grants (MEG) and Gerontology Research Grants.
LKB1 Knockout in Skeletal Muscle Improves High Fat Diet‐Induced Insulin Tolerance, but not Glucose Tolerance
Authors: Chen Ting , Thomson David M. 
Published: November 2023

Many studies have shown that a long‐term high fat diet can induce impaired glucose and insulin tolerance in mice. In skeletal muscle, LKB1 is a master kinase regulating the AMPK family of protein kinases, which are major regulators of metabolism. LKB1‐knockout in muscle has been shown to improve insulin sensitivity. In this study, we asked whether skeletal muscle specific LKB1‐knockout (KO) can protect mice from long‐term high fat diet‐induced impairment in glucose and insulin tolerance. Control (CON) and littermate LKB1‐KO (KO) mice were fed either high fat (HF) chow or standard (STD) chow for 14 weeks. Body weight and retroperitoneal fat weight increased similarly with HF diet feeding in both CON and KO mice, while the HF diet didn't affect heart and muscle weight. HF diet significantly (p≤0.05) worsened both glucose and insulin tolerance for both CON and KO mice, but the effect on insulin tolerance (but not glucose tolerance) was attenuated by 30.7% in KO vs. CON mice. Phosphorylation of AS160 (an important regulator of glucose transporter‐4 translocation and glucose uptake) at the Akt‐target site, Ser318, increased 64.7% with HF diet in the KO, but did not change in CON mice. Therefore, knocking out LKB1 in skeletal muscle can improve long‐term high fat diet‐induced insulin tolerance, and this may be through increased AS160 phosphorylation.Support or Funding InformationThis work was funded by Brigham Young University a Mentoring Environment Grant and a Graduate Research Fellowship Award.
Micro‐RNA 203 Regulates Myometrial Smooth Muscle Cell Expression of the Transient Receptor Vanilloid 4 Channel
Authors: Ying Lihua , Barnes Elizabeth A , Rodriguez Saidie , Alvira Cristina M , Cornfield David N 
Published: November 2023

BackgroundWe recently demonstrated that the expression and activity of the transient receptor vanilloid 4 (TRPV4) channel increase in myometrial smooth muscle cells (mSMC) during pregnancy. However, the molecular mechanisms that dynamically regulate TRPV4 expression and activity have not been identified. Accumulating evidence suggest that micro RNA molecules (miRNA) may influence the physiology of pregnancy by regulating the expression of molecules that affect implantation, uterine contraction, inflammation, and cervical remodeling. Although miR‐203 represses TRPV4 expression in chondrocytes, whether pregnancy associated changes in miR‐203 expression contribute to the heightened expression of TRPV4 in the pregnant myometrium remains unknown.ObjectiveWe hypothesized that with pregnancy, mSMC miR‐203 expression decreases as TRPV4 expression increases.MethodsTo test these hypotheses, miR‐203 and TRPV4 expression was determined by qPCR in primary mSMC isolated from non‐pregnant and pregnant (D18) mice. TRPV4 gene expression was also determined in human mSMC that were transfected with either non‐targeting control (NTC) or a miR‐203 mimetic. In separate studies, mSMC contraction was assessed in human mSMC transfected with either NTC or miR‐203 mimetic that were embedded in collagen gels.ResultsmiR‐203 levels were almost 14‐fold higher in the non‐pregnant as compared to late pregnant mSMC (2.38±0.76 vs. 0.17±0.05, p=0.04). Treatment of human mSMC with the miR‐203 mimic increased miR‐203 expression by over 2000‐fold (p<0.0001), and decreased TRPV4 expression by approximately 90% (p=0.013). In addition, in the collagen gel assays, gels containing mSMC transfected with miR‐203 demonstrated an increase in area of 17% (p=0.016, versus control), consistent with relaxation.ConclusionsThese data demonstrate that in mSMC, miR‐203 suppresses TRPV4 gene expression. We speculate that reductions in miR‐203 expression during late gestation may allow for increased expression of TRPV4 near term, and represent a viable target to suppress uterine contractility, prolong pregnancy and prevent preterm delivery.Support or Funding InformationBurroughs Wellcome Fund, Pretern Birth Intiative
Regulation of Glucose Metabolism by Contractile Activity in Human Skeletal Muscle Myotubes from Severely Obese Individuals
Authors: Park Sanghee , Houmard Joseph 
Published: November 2023

IntroductionExercise/ or contractile activity can enhance insulin sensitivity and oxidative capacity in skeletal muscle. However, the effects of contractile activity in skeletal muscle from severely obese individuals still remain unestablished.PurposeWe investigated insulin‐stimulated glucose metabolism in primary skeletal muscle myotubes from severely obese individuals (BMI ≥ 40 kg/m2) in response to contractile activity induced by electrical pulse stimulation.MethodFully mature myotubes from lean (BMI: 23.1 ± 0.7 kg/m2) and obese (BMI: 44.9± 2.5 kg/m2) individuals were stimulated for 24‐hours by applying an electrical pulse at 11.5 V, 1 Hz and 2 ms. Following contraction, insulin was added to examine the combined effects of muscle contraction and insulin on anabolic signaling.ResultIn myotubes from the severely obese individuals, insulin‐stimulated glycogen synthesis and glucose oxidation were normalized to the levels seen in muscle from the lean subjects without electrical stimulation. However, responses to electrical stimulation were blunted in the severely obese vs. lean subjects in terms of the magnitude of the improvements in insulin‐stimulated glucose metabolism. In addition, electrical stimulation increased insulin‐stimulated lactate production in severely obese but not lean subjects. Electrical stimulation increased adenosine monophosphate (AMP) accumulation and AMP‐activated protein kinase (AMPK) signaling, but to a lesser degree in myotubes from the severely obese donors. Electrical stimulation provided an improvement in insulin signal transduction in lean but not severely obese individuals. Especially, sites on AS160 phosphorylation (T642, S588, S341) showed enhanced response to electrical stimulation in lean but no changes in severely obese individuals.ConclusionThese data reveal that in the skeletal muscle of severely obese individuals, contractile activity can improve insulin‐stimulated glucose metabolism independent of insulin signaling. In addition, transient increase in AMPK signaling by accumulation of AMP for contractile activity appears to play a critical role in enhancing glucose metabolism in severely obese individual in response to electrical stimulation.Support or Funding InformationDK56112
Exercise training regulates autophagy in aorta
Authors: Okutsu Mitsuharu , Yamada Mami , Uto Taiki , Hokazono Chihiro 
Published: November 2023

ObjectiveAtherosclerosis, an inflammatory vascular disease in large‐ and medium sized arteries, is characterized by the formation of atherosclerotic plaques. It has been demonstrated that exercise training decreases atherosclerotic plaque formation and reduces the levels of circulating pro‐inflammatory cytokines; but it is unknown how reduction of inflammatory cytokines by exercise contribute to the inhibition of atherosclerosis. Autophagy is a reparative and life‐sustaining process by which cytoplasmic components are sequestered in double‐membrane vesicles and degraded upon fusion with lysosomal compartments. Recent studies indicate that autophagy is stimulated in advanced atherosclerotic plaques by oxidized lipids, metabolic stress and inflammation. However, it is not clear whether exercise training modulates autophagy in arteries.MethodsHere, we examined whether exercise training regulates autophagy in the aorta of male C57BL/6J and apolipoprotein E deficient mice. C57BL/6J were fed normal chow. Apolipoprotein E deficient mice were fed 45% high‐fat diet to induce atherosclerosis. Mice were randomly assigned into exercise training groups and sedentary group. Exercise training mice were individually housed in cages equipped with a running wheel for 16 weeks. Heart, aorta, blood and plantaris muscle were harvested at 24 hours after the last bout of exercise. To quantify atherosclerotic lesions, we stained aortic root sections with Oil Red O and hematoxylin‐eosin. Autophagy protein expression in aorta was analyzed by western blot. Serum inflammatory cytokines were measured by Proteome Profile Antibody Arrays.ResultsVoluntary running in C57BL/6J mice resulted in reduced autophagy flux (i.e., a combination of decreased LC3‐II/LC3‐I ratio, LC3‐II levels and tend to increase p62/sequestosome 1 protein content) in aorta. Exercise training significantly reduced atherosclerotic plaque area at the aortic root in apolipoprotein E deficient mice. Autophagy flux in the aorta was significantly lower in exercise trained apolipoprotein E deficient mice when compared to sedentary mice. Serum inflammatory cytokines in exercise trained apolipoprotein E deficient mice were significantly lower than sedentary mice.ConclusionsThese results suggest that the regular exercise‐mediated reduction of inflammatory cytokines is also associated with a potential decrease in autophagy levels in aorta, which may contribute to the attenuation of atherosclerosis.Support or Funding InformationGrant‐in‐Aid for Challenging Exploratory Research (26560404) to Okutsu M.
Recovery of Running Wheel Activity in Nursing Dams
Authors: Murphy Robert J , Welshhans Elizabeth A , O'Hagan Kathleen P 
Published: November 2023

Rats provided with cage running wheels engage in daily spontaneous exercise (EX), and this model is used to study the impact of EX on maternal and fetal outcomes in normal and compromised pregnancies. Previously we reported that normal gestation in rats is marked by progressive decreases in exercise volume primarily through decreases in time rather than velocity. Here we report the recovery of EX over 5 weeks postgestation and address the hypothesis that the presence of nursing pups in the cage attenuates recovery of EX by dams. Female Sprague‐Dawley rats were housed individually with cage wheels and divided into Time Control (TC, N=9) and Pregnant groups (bred, N=17). The Pregnant group was subdivided into Pups‐Kept (N=9) and Pups‐Removed (N=8) groups at the time of parturition. Cage revolutions were detected by a bike computer and accumulated distance (m), time (min) and average velocity (m/min) were calculated for contiguous 24 hr periods. Daily data were averaged in bins of 7 days: Nonpregnant (1 bin), gestation (G; 3 bins), postgestation (PG, 3 bins) and postweaning (PW, 2 bins) for statistical analysis (ANOVA; Mean[SD]). Here we present the time data as the distance response was qualitatively similar. Average daily EX time was 164 (61) (n=26) in the nonpregnant state. EX time during 3rd week of gestation was reduced by 85% (10) in pregnancy (n=17) and 11% (19) in TC rats (P<0.001). Surprisingly, EX time (see table below) showed little increase moving from week 1 to week 2 (P=0.4) but was greater in the Pup‐Removed vs the Pup‐Kept groups as postgestation moved from week 2 to week 3 (Interaction contrast, P=0.04). Once the pups were weaned, the Pup‐Kept group increased EX time slightly more than the Pup‐Removed group (interaction contrast, P=0.049) and there was no further increase in EX time (P=0.9) during the 2nd week postweaning. EX time was not different in TC vs Preg groups at PW2 (P=0.6) although overall, EX time decreased 20% (41) over the ~60 day period of time (P=0.003). Surprisingly, the lack of pups had little effect on spontaneous EX in rat dams during the first 2 weeks postgestation, suggesting that metabolic energy conservation or time for nursing are probably not primary reasons for the slow recovery of exercise volume after parturition. Recovery of exercise volume accelerates during week 3 postgestation, and this recovery is accentuated in rats without nursing pups.Support or Funding InformationSupported by Midwestern University

Daily wheel time in min averaged over 7 day periods

NP
PG1
PG2
PG3
W1
W2

TC
182 (57) N=9

125(64) N=6

P‐Kept
176 (70)
43(16)
44(18)
58(19)
114(48)
126(55)

P‐Remove
132(46)
55(30)
63(51)
102(54)
114(60)
101(31)

Mean(SD)

Interaction:
PG 2 vs 3, P=0.04
PG3 vs W1, P=0.05
All Rats;Vs NP, P<0.003