bluuebunny/crossref_metadata_2025 huggingface dataset:
Eicosapentaenoic acid regulates brown adipose tissue gene expression and metabolism in high fat fed mice (1037.5)
Authors: Pahlavani Mandanna , Kalupahana Nishan , LeMieux Monique , Aljawadi Arwa , Scoggin Shane , Claycombe Kate , Moustaid‐Moussa Naima
Published: June 2021

Brown adipose tissue (BAT) is a thermogenic tissue, a key regulator of energy balance and a potential therapeutic target for obesity. We previously reported that eicosapentaenoic acid (EPA) reduced high fat (HF) diet‐induced obesity and insulin resistance in mice, independent of energy intake. We hypothesized that these effects are mediated in part by BAT thermogenesis. Using mice fed HF or HF‐EPA diets for 11 weeks, we demonstrated that BAT from HF‐EPA mice expressed higher mRNA levels of thermogenic genes such as fibronectin type lll domain containing 5 (FNDC5), peroxisome proliferator activated receptor gamma coactivator 1 alpha (PGC1α) and uncoupling protein 3 (UCP3), compared to HF mice. EPA also induced expression of angiotensinogen (Agt) gene and other genes related to insulin sensitivity such as Glut 1 while downregulating arachidonate 5‐lipoxygenase (ALOX5), an inflammatory biomarker. At the protein level, EPA upregulated uncoupling protein (UCP) and downregulated fatty acid synthase (FAS). Thus, EPA exerts dual effects on adipose tissue depots, by reducing WAT inflammation and lipid accumulation, while activating BAT thermogenesis and reducing lipogenesis. In conclusion, EPA exerts differential tissue specific effects to reduce obesity‐associated metabolic disorders. Further molecular studies in cultured brown adipocytes are being conducted to dissect direct effects of EPA on brown fat.

Grant Funding Source: Supported by AHA, USDA and TTU
Enhance intestinal lymphatic transport of lipophilic bioactive food components by nanoemulsion delivery system (1044.16)
Authors: Yao Mingfei , Zheng Jinkai , McClements David , Xiao Hang
Published: June 2021

One way to enhance bioavailability of lipophilic nutraceuticals is to facilitate their intestinal lymphatic transport. We studied the effects of triglycerides‐based nanoemulsion delivery systems with different fatty acid chain lengths on the intestinal lymphatic transport of a highly lipophilic flavonoid, 5‐demethylnobiletin (5DN). 5DN was encapsulated in medium chain triglycerides (MCT) or long chain triglycerides (LCT) based nanoemulsions. These systems were subject to a simulated gastrointestinal digestion model. The resulted mixed micelle phase that contained bioaccessible portion of 5ND was applied to Caco‐2 monolayer cell model that mimics intestinal absorption. We observed that 30% of 5DN underwent intestinal lymphatic transport when 5DN was encapsulated in LCT‐based emulsion, while only 5% of 5DN underwent intestinal lymphatic transport in case of MCT‐based emulsion. Moreover, much more Apo B protein was secreted in the enterocytes by the stimulation of the digesta produced from LCT‐based emulsion in comparison to MCT‐based emulsion. This suggested more chylomicrons were formed in the enterocytes as the result of digestion of LCT‐based emulsion. In conclusion, we demonstrated that LCT‐based emulsion was more potent in enhancing the bioavailability of lipophilic components through increased lymphatic transport in comparison to MCT‐based emulsion.

Grant Funding Source: Supported by USDA
Biotransformation of citrus polymethoxyflavones in rats and mice (1044.22)
Authors: Zheng Jinkai , Song Minyue , Qiu Peiju , Dong Ping , Cai Xiaokun , Xiao Hang
Published: June 2021

Biotransformation plays important roles in dictating biological activities of orally ingested agents including all bioactive food compounds. We investigated biotransformation of four representative citrus polymethoxyflavones (PMFs), i.e. nobiletin, tangeretin, 5‐demethylnobiletin and 5‐demethyltangeretin in both rats and mice after long‐term oral consumption. Four PMFs were administered individually to rats and mice through diet at different doses for 10‐20 weeks. Their feces and urine were collected in metabolic cages. Utilizing NMR, MS and HPLC techniques, we identified more than 20 metabolites of these PMFs in the fecal and urine samples. We optimized the extraction and HPLC analysis conditions so that we can simultaneously quantify all PMFs and their metabolites in a single HPLC run with high sensitivity. Our results showed that all four PMFs underwent extensive demethylation reaction followed by conjugation reactions (mainly sulfation and glucuronidatioin). However, the ratios between conjugated and unconjugated metabolites in the feces and urine are largely different. Cell culture studies demonstrated that metabolites in feces had much stronger anti‐cancer and anti‐inflammatory effects in comparison with those from urine, which was contributed to certain unconjugated fecal metabolites. Our results warrant further investigation on the effects of fecal metabolites on colon health.

Grant Funding Source: Supported by NIH, AICR and USDA
Chronic hypoxia suppresses muscarinic‐induced contractility in ovine pulmonary arteries (1089.17)
Authors: Giang Michael , Paez Ricardo , Kim Joon , Blood Quintin , Longo Lawerence , Wilson Sean
Published: June 2021

Muscarinic acetylcholine receptor (mAChR)‐ arterial relaxation is often used to test for a functional endothelium, but some show it can cause constriction. The present studies tested the hypothesis that mAChR activation contracts pulmonary arteries (PA) with intact endothelium and examined age and altitude effects on mAChR activation. This hypothesis was tested by performing wire myography on endothelium intact as well as denuded PA from chronic hypoxic (CH) term‐fetal and adult sheep that lived at 3,200 m for >100 days or normoxic sheep that lived at 720 m. Dose‐dependent contraction to carbachol (CCH; 1nM‐100 μM), a mAChR agonist and bradykinin (BK; 10 pM‐1 μM) were examined in phenylephrine preconstricted PA (PE; 10 μM). CCH caused a dose‐dependent contraction of PA from adult sheep, while fetal PA contracted to a lesser extent. BK (1 μM) relaxed CCH constricted PA, showing the endothelium was functional. Chronic hypoxia suppressed mAChR‐ contraction of denuded PA in fetuses and adults. M2 receptors dominated in fetus, while M3 receptors were central in adult, suggesting a developmental isoform switch. Because parasympathetic nerve activation contracts airways through mAChR activation potentially there is co‐constriction of associated PA. This mAChR contraction of PA may provide a novel mechanism that matches ventilation to perfusion in the lung.

Grant Funding Source: Supported by NSF MRI923559, NIH HD‐69746, P01HD31226,R01HD3807,P20MD6988,LLUSOM, Macpherson Society
Hyperoxia increases free radical production in rat brain slices in the dorsal CO2‐chemosensitive area of the caudal medulla oblongata (1092.5)
Authors: Ciarlone Geoffrey , Dean Jay
Published: June 2021

Hyperoxia stimulates breathing and activates putative CO2 chemoreceptor neurons in the caudal solitary complex (cSC). We have previously shown that 95%O2‐the typical level of control O2 used for brain slice studies‐establishes an abnormally high tissue pO2 throughout the slice and is a powerful stimulant of neuronal activity in the cSC when using a lower level of control O2 (40%). Likewise, hyperbaric O2 has similar stimulatory effects on firing rate of cSC neurons, particularly CO2‐excited neurons, which are mimicked by chemical oxidants and abolished by antioxidants. Now we test the hypothesis that 95%O2 increases the rate of production of reactive O2 and N2 species in the cSC in slices maintained in 40%O2 (control). Fluorescence microscopy was used to measure the rate of superoxide (⋅O2‐, DHE) and nitric oxide (⋅NO, DAF‐FM DA) production. Our findings show that the rates of ⋅O2 and ⋅NO production increased, respectively, in 95%O2 vs. 40%O2, but only in the presence of NOS and SOD inhibitors (to prevent consumption of ⋅O2‐ by its reactions with ⋅NO and SOD) or SOD mimetics (to prevent consumption of ⋅NO by its reaction with ⋅O2‐). We conclude that 1) using 95%O2 in slices produces an enhanced redox and nitrosative environment that modulates excitability of cSC neurons, including CO2‐chemosensitive neurons; and 2) measurement of ⋅O2‐ using DHE or ⋅NO using DAF‐FM DA is affected (blunted) by downstream reactions that consume the reactive species of interest.

Grant Funding Source: ONR
Urea protects Caenorhabditis elegans against hypertonic stress: a genetic model for cellular responses to urea? (1099.7)
Authors: Perez Esteban , Choe Keith
Published: June 2021

Urea is a cell‐permeable nitrogenous waste product that denatures macromolecules and causes cellular stress at high concentrations. However, urea accumulates in the mammalian renal medulla as a part of the urine concentrating mechanism and in elasmobranch fish to balance the high osmolarity of seawater. Although high concentrations of urea can be detrimental, pre‐exposure of mammalian cells to moderate concentrations promotes resistance to high concentrations of the impermeable osmolyte NaCl in addition to high urea. Although the mechanisms of this conditioning are poorly defined, studies to date indicate that they are largely distinct from pathways activated by high levels of NaCl. The nematode Caenorhabditis elegans can tolerate extremely high levels of NaCl and other impermeable osmolytes in part by accumulating the organic osmolyte glycerol and by modulating protein translation. Here, we conducted a series of experiments investigating the effects of urea in C. elegans to determine if this genetically tractable system might be useful for defining protective mechanisms. We find that C. elegans can tolerate extremely high levels of urea (~600 mM) and that pre‐exposure to moderate urea promotes resistance to high urea and high NaCl. Therefore, the general protective effects of moderate urea levels appear to be highly conserved and therefore amenable to genetic analysis in C. elegans. Our ongoing studies include determining if the mechanisms of urea protection in C. elegans are distinct from those initiated by NaCl.

Grant Funding Source: NSF Grant IOS1120130 to KPC
The development of dive capacity in northern elephant seal pups during the post‐weaning fast (1100.14)
Authors: Somo Derek , Ensminger David , Sharick Jeffrey , Kanatous Shane , Crocker Daniel
Published: June 2021

The post‐weaning fast (PWF) in seals has been associated with development of the physiological and behavioral capacity to perform the breath‐hold dives which characterize at‐sea behavior in these species. Previous studies in juvenile northern elephant seals (Mirounga angustirostris) indicate that the duration of the PWF varies substantially with body reserves at weaning, and many suggest that the terrestrial PWF enables juveniles to develop the physiological capacity to dive before initiating independent foraging at sea. However, few studies have examined the effect of magnitude of body reserves at weaning on development of dive capacity. We measured energy reserves at weaning and made longitudinal measurements of components of blood and muscle oxygen stores, thyroid and glucocorticoid hormones, iron status markers, muscle metabolic enzyme activities, and field metabolic rate in northern elephant seal pups during the first 8 weeks of the PWF. Our objective was to assess the impacts of body reserves at weaning on the rate of development during the first 8 weeks of the PWF. Although myoglobin concentration, a critical determinant of the muscle oxygen store, increases during the first eight weeks of the PWF, other key components of aerobic diving capacity do not increase during this same time period. When the magnitude of body reserves at weaning impacted the measured parameters of aerobic dive capacity, pups with smaller body reserves at weaning tended to exhibit greater cumulative increases across the PWF. Pups with smaller body reserves at weaning develop greater mass specific oxygen storage capacity during the first 8 weeks of the PWF. However, the greatest changes in dive capacity may occur near the end of the fast or after juveniles have left the natal rookery to initiate independent foraging.

Grant Funding Source: Supported by NSF
Baseline hematology in Tursiops truncatus (Atlantic bottlenose dolphins), Roatan, Honduras (1100.16)
Authors: Pogue Connor , Maiden Tracina
Published: June 2021

Hematology studies are key tools in determining the health status of marine mammals in captive and wild populations. Large variations from average values in blood chemistry can mean illness or stress caused by disease, handling, or a combination of environmental factors. However, few comprehensive hematology studies have been done on marine mammals (Fair, 2006). This study examines baseline blood chemistry in open‐water captive Tursiops truncatus (Atlantic Bottlenose Dolphins). A complete blood panel was taken for general health examinations from the dolphins located at the Anthony’s Key Resort facility in Roatan, Honduras from 2003‐2013. The Anthony’s Key Resort dolphin enclosure is an open water pin that is part of the Atlantic Ocean. Hematological samples were taken on a regular basis in order to monitor chemistry changes in the dolphin population located at the facility. Standard ranges of blood chemistry for the dolphins at this facility were obtained by calculating averages from all standard values throughout the tested population. Mathematical calculations were used to find trends in the data based on the ages of the individuals to create baseline values for blood chemistry in the dolphin population. The data was separated by age of the dolphins at the time of the sample in order to minimize the effects that age has on the variability of blood chemistry. Values obtained include the mean and standard deviation of the following: white blood cells, neutrophils (banded and segmented), lymphocytes, eosinophils, etc. The data obtained from this study, along with other studies, is crucial in determining general blood chemistry parameters for Tursiops truncatus. This information can be used to aid researchers in monitoring the health status of wild, captive, and open‐water captive populations of Atlantic Bottlenose Dolphins.

Grant Funding Source: NSF# 1118679 Collaborative Research: Community College Undergraduate Research Initiative (CCURI)
Regulation of avian PPAR activity by dietary fatty acids (1101.11)
Authors: Hamilton Angelica , Ly Jennifer , Corder Keely , Schaeffer Paul , Huss Janice
Published: June 2021

Migratory birds undergo metabolic remodeling, including increased adiposity and skeletal muscle fatty acid oxidation, in preparation for long‐distance flight. Peroxisome proliferator‐activated receptors (PPARs) are lipid‐activated nuclear receptors that regulate lipid metabolic pathways overlapping those altered in migrating birds. To examine whether PPARs regulate adaptive metabolic changes in response to fattening, we used Gray Catbird as the focal species. PPAR isoforms cloned from catbird share high amino acid identity with mammalian homologs (% vs mouse): gcPPARα (83.8%), gcPPARδ (83.5%), gcPPARγ (85.3%). We tested whether gcPPARs activate fatty acid (FA) utilization genes using Lpl and Cpt1b promoter‐luciferase reporters in cells. Saturated and unsaturated C‐16 and C‐18 FAs are enriched in adipose of migrating birds. In C2C12 myocytes gcPPARα was most robustly activated by the saturated FAs, 18:0 stearic (+60%) and 16:0 palmitic (+50%); while gcPPARδ showed greater activation by 18:1 oleic (+80%), an unsaturated FA. In CV1 cells gcPPARγ was most responsive to 20:5 eicosapentaenoic (+60%) and 18:2 linoeic acid (+40%), similar to mouse PPARγ. Overexpression of PPARs increased lipid droplets in cells suggesting enhanced fatty acid uptake and/or oxidation. Differential FA effects on gcPPARs may mediate selective activation of metabolic gene programs in skeletal muscle and adipose tissue.

Grant Funding Source: NSF IOS‐1257455
Muscle oxygen saturation during hyperthermic central hypovolemia (1104.21)
Authors: Schlader Zachary , Rivas Eric , Kennedy Naomi , Kern Jena , Soller Babs , Convertino Victor , Crandall Craig
Published: June 2021

During normothermia, a reduction in near infrared spectroscopy (NIRS) derived muscle oxygen saturation (SmO2) is an indicator of central hypovolemia. Hyperthermia reduces tolerance to central hypovolemia. This study tested the hypothesis that reductions in NIRS derived SmO2 would be similar throughout normothermic and hyperthermic central hypovolemia to pre‐syncope. Ten healthy males (32 ± 5 y) underwent central hypovolemia via progressive lower‐body negative pressure (LBNP) to pre‐syncope during normothermia and hyperthermia (+1.2 ± 0.1°C increase in internal temperature). NIRS derived SmO2 (Reflectance Medical Inc.) was measured throughout and analyzed as the absolute change from pre‐LBNP. Hyperthermia reduced (P<0.001) LBNP tolerance by 38 ± 19%. Pre‐LBNP SmO2 was similar (P=0.654) between normothermia (74.1 ± 5.0%) and hyperthermia (72.6 ± 6.9%). SmO2 decreased (P<0.001) throughout LBNP, but the absolute reduction from pre‐LBNP to pre‐syncope was greater (P=0.018) during normothermia (‐10.0 ± 5.7%) than during hyperthermia (‐5.7 ± 4.5%). These data indicate that hyperthermia influences the magnitude of the reduction in NIRS derived SmO2 during central hypovolemia to pre‐syncope. However, a potentially confounding influence of hyperthermia‐induced increases in skin blood flow affecting the NIRS derived SmO2 signal cannot be discounted.

Grant Funding Source: DOD Grant 110475007
Active and passive heat stress similarly compromises tolerance to a simulated hemorrhagic challenge (1104.22)
Authors: Pearson James , Lucas Rebekah , Schlader Zachary , Zhao Jiexiu , Gagnon Daniel , Crandall Craig
Published: June 2021

Passive heat stress increases core and skin temperatures and reduces tolerance to simulated hemorrhage, as assessed via lower body negative pressure (LBNP). It is unknown whether exercise induced heat stress reduces LBNP tolerance to a similar extent relative to passive heat stress. Eight males (32 ± 7 yrs, 176 ± 8 cm, 77.0 ± 9.8 kg) underwent LBNP to pre‐syncope on three separate and randomized occasions: passive heat stress and two occasions of exercise induced heat stress where skin temperature was moderate (~36°C, Active 36) or warm (~38°C, Active 38). LBNP tolerance was quantified using the cumulative stress index (CSI). Prior to LBNP, increases in core temperature were similar in all trials (1.18 ± 0.20°C; P < 0.05), and while mean skin temperature was similar between passive heat stress (38.2 ± 0.5°C) and Active 38 (38.2 ± 0.8°C; P = 0.90) both trials were greater compared to Active 36 (36.6 ± 0.5°C; P < 0.05). LBNP tolerance was not different between passive heat stress and Active 38 (383 ± 223 and 322 ± 178 CSI; P = 0.12) but both were similarly reduced relative to the Active 36 (516 ± 147 CSI, both P < 0.05). At pre‐syncope mean arterial pressure and heart rate were not different between trials. These data suggest that tolerance to a simulated hemorrhagic challenge is similar following passive and exercise induced heat stress when skin temperatures are similarly elevated.

Grant Funding Source: DOD: W81XWH‐09‐2‐0194 and NIH: HL61388
Effects of environmental temperature and humidity on a model of exertional heat stroke in mice (1104.26)
Authors: King Michelle , Leon Lisa , Clanton Thomas
Published: June 2021

Effects of environmental temperature and humidity on a model of exertional heat stroke in mice Michelle A. King1, Lisa R. Leon2, and Thomas L. Clanton1 1 Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Florida; 2U.S. Army Research Institute of Environmental Medicine, Thermal and Mountain Medicine Division, Natick, Massachusetts.

The pathophysiology of exertional heat stroke (EHS) may differ from passive heat stroke, but limited models are available. We describe EHS in conscious C57Bl/6 mice, instrumented with telemeters and exposed to environmental temperatures (Tenv) from 37.5‐39.5C, and relative humidities (RH) from 30‐90%. Mice exercised on a forced running wheel using an incremental protocol until neurological symptoms (fainting) became limiting. All animals survived 4 d. No significant differences were seen between max core temperatures (Tmax=42.1‐42.5C) at differing Tenv, when RH=30‐50%. Paradoxically, at 90% RH, symptom‐limited Tmax averaged 41.50.1C (P<0.01). However, exercise time and peak running speed were highest at 90% RH (P<0.05). The minimum core temp reached during hypothermia was also significantly higher at 90% vs. 30% RH (P<0.025). Thermal loads were highest at Tenv=37.5C, irrespective of RH (P<0.01). However, the percent loss of body weight (3‐11.5%) was not different in any condition. The results demonstrate that similar forms of EHS can be observed in mice over a wide range of Tenv and RHs, resulting in symptoms, Tmax and other characteristics resembling human EHS. Author views not official US Army or DoD policy.

Grant Funding Source: USARIEM, Natick MA
Computational modeling of the effects of temperature on chemosensitive locus coeruleus neurons from bullfrogs (1128.3)
Authors: Putnam Robert , Quintero Maria , Santin Joseph , Cordovez Juan , Hartzler Lynn
Published: June 2021

Chemosensitive LC neurons from bullfrogs increase their firing rate and have altered action potential (AP) waveforms upon cooling from 20°C to 10°C (Santin et al., Amer. J. Physiol. Doi:10.1152/ajpregu.00348.2013). We developed a computational model to study this unusual neuronal response to cold temperature. Using MatLab, we have a 4 dimensional model based on a Hodgkin‐Huxley formulation that includes a voltage‐gated Na channel, a delayed‐rectifying K (Kdr) channel and a leak K channel. The model generates a firing rate of ~12 Hz and AP waveforms that are similar to those of bullfrog LC neurons at 20°C. For instance, values (neuron:model) for AP height (60 mV:51 mV), maximum rate of depolarization (36 mV/ms:40 mV/ms), maximum rate of repolarization (‐27 mV/ms:‐23 mV/ms), the AP width (2.1 ms:2.6 ms) and after hyperpolarization (AHP) (‐60 mV:‐66 mV) are similar comparing the model to the actual neuron. Colder temperature (10°C) decreases neuronal maximum rates of depolarization and repolarization, increases the AP width, and decreases the AHP. Changing, in a depolarizing direction, the voltage at which the time constant of inactivation for Kdr channels reaches a maximum and increasing the time constant for Na channel activation in the model results in similar changes in AP waveform parameters. However, the model changes result in decreased firing rate (~6 Hz) while temperature changes in neurons result in increased firing rate. This suggests that another channel is involved in the temperature effects on firing rate. In line with this, we found a hyperpolarization‐activated current (IH) in LC neurons that will be added in our model to determine if altering the parameters of the IH current contributes to cold temperature‐induced increased firing rate in bullfrog LC neurons. We ultimately plan to use both the model and electrophysiology studies to gain insights into the neuronal basis for chemosensitivity and cold temperature responses in chemosensitive LC neurons from bullfrog.

Grant Funding Source: Supported by Admin. Dept. of Sci., Technol. & Innov. of Col (COLCIENCIAS) and NSF Grant IOS‐1257338.
Endocannabinoid effects on neuronal function in the NTS of hypertensive rats (1130.3)
Authors: Hopp Francis , Dean Caron , Seagard Jeanne
Published: June 2021

Previously, we showed that endocannabinoid activation of cannabinoid 1 receptors (CB1Rs) in the nucleus tractus solitarius (NTS) activates barosensitive neurons and prolongs baroreflex inhibition of renal sympathetic nerve activity in normotensive Sprague Dawley (SD) rats, but reflex responses were attenuated in spontaneously hypertensive rats (SHR). This study examined the effect of CB1Rs on NTS barosensitive neurons in SHRs to determine if the lack of reflex responses is associated with diminished effects on neuronal firing. NTS neuronal activity was recorded in the working heart brainstem preparation in SHR or SD rats, with increases in perfusion pressure used to identify barosensitive firing. To examine the effects of CB1Rs on neuronal discharge, picoejections of the CB1R agonist anandamide (AEA), antagonist SR141716, or blocker of AEA catabolism, AM404, were made through a multibarrel pipette array which contained the carbon fiber recording electrode. AEA acting at CB1Rs increased barosensitive neuronal firing in SD versus SHR rats. In addition, discharge of respiratory I neurons, identified by correlation to phrenic nerve discharge, was found to respond more to CB1R activation in SD rats versus SHRs. The data indicate that neuronal function of CB1Rs in the NTS is blunted in SHRs.

Grant Funding Source: Suppoted by VA Merit Review I01 BX000481 (JLS), NSF Award IOS 0751613 (CD)
Role of histamine in the sensory motor integration of gill lateral cell cilia in the bivalve mollusc, Crassostrea virginica (1131.1)
Authors: Akande Patrick , Duncan Jened , Catapane Edward , Carroll Margaret
Published: June 2021

Lateral gill cells of Crassostrea virginica are innervated by serotonin and dopamine nerves from their ganglia. Most bivalves have lateral cell cilia that respond to serotonin and dopamine. The motor aspects have been well studied, but not the sensory side. There is limited information about sensory inputs. We found C. virginica can sense and adjust gill cilia beating to the presence of food and a variety of chemical cues including histamine (HIS). HIS does not alter beating when applied to gill, but when applied to mantle rim decreases beating. Detaching the mantle rim or transecting the branchial nerve prevents this. We hypothesize HIS is a sensory neurotransmitter in mantle rim involved in sensory‐motor integration of gill lateral cilia. We studied actions of HIS and 3 different classes of HIS receptor antagonists. Cilia beating was measured by stroboscopic microscopy. Adding HIS (10‐6 ‐ 10‐3 M) to mantle rim decreased cilia beating. H1 antagonist diphenhydramine and H2 antagonist famotidine blocked HIS over the range of 10‐3 ‐ 10‐9. Conessine a H3 antagonist did not block HIS. The study further demonstrates a sensory‐motor integration of beating of lateral cilia involving the sensory mantle rim and visceral ganglia and suggests HIS is a sensory neurotransmitter in mantle receptor cells that synapses with afferents going to the VG where signals are integrated resulting in a motor response to the gill lateral cells.

Grant Funding Source: NIH‐2R25GM06003, NSF‐0622197, NYSED‐ 0516041071
miRNA expression profile in non‐human primate in response to Yersinia pestis infection (1138.3)
Authors: Dimitrov George , Moyler Candace , Gautam Aarti , Kumar Raina , Hammamieh Rasha , Jett Marti
Published: June 2021

miRNA expression profile in non‐human primate in response to Yersinia pestis infection George Dimitrov, Candace Moyler, Aarti Gautam, Raina Kumar, Rasha Hammamieh and Marti Jett Integrative Systems Biology Program, US Army Center for Environmental Health Research 568 Doughten Drive, Fort Detrick, MD 21702‐5010 MicroRNAs (miRNAs) are small non‐coding RNA molecules, 20‐30 nucleotides in size, that suppress gene expression at both transcriptional and post‐transcriptional levels. Recent studies indicate that miRNAs play significant roles in pathogen‐host interactions. Yersinia pestis is a gram‐negative obligate pathogen and the causative agent of plague, which throughout history has had a devastating effect on human population. We carried out miRNA profiling studies in tissues and blood samples collected from African green monkeys (Cercopithecus aethiops) exposed to aerosolized Y. pestis CO92. These studies enabled us to examine and identify the tissue‐specific differences in small RNA expression profiles during pathogen‐host interactions, and to detect their regulation patterns during the progression of disease. For this study, we used a small RNA Illumina deep sequencing method. Total yields of clean sequencing reads ranging from 17009208 to 11126920 were obtained after removing adaptor contamination and quality filtering. The size distribution of small RNAs (miRNA) ranged from 20 to 24 nt, which accounted for 38 percent of the total reads. The miRNA precursor and mature miRNA expression profiles were created. These will allow us to study the expression profile for tissue‐specific miRNA across different time points.

Grant Funding Source: TMTI0029_09_WR_T from the Department of Defense
Prenatal hypoxia modifies cardiac performance in adult bobwhite quail, assessed by pressure‐volume loop analysis (1150.10)
Authors: Flores‐Santin Josele , Burggren Warren
Published: June 2021

Prenatal hypoxia modifies cardiac performance in adult bobwhite quail, assessed by pressure‐volume loop analysis Josele Flores‐Santin1 joselefloressantin@my.unt.edu, Warren Burggren1 Burggren@unt.edu1University of North Texas, Biology department, 1155 Union circle, Denton Texas U.S.

The consequences of early embryonic stressors and how they affect subsequent adult life reflects the concept of “fetal programming”. This programming potentially produces functional anomalies in major organs including the lungs, the kidneys and the heart, based on studies of a limited number of “traditional” animal models for fetal programming. The aim of this project is to use a non‐traditional model ‐ the rapidly maturing bobwhite quail ‐ to study the effects of embryonic stressors as they manifest themselves in adults, with an emphasis on the working heart. The fast development along with the small size of quail makes them a potentially important alternative animal model to study cardiovascular physiology and the changes that prenatal stressors produce on it. In this study we submitted quail eggs to hypoxia (15%). This treatment accelerated hatching by one day (26±0.11) in comparison to controls (27.6±.12). The treatment also induced a lower hatching mass (6.9±1.0) than controls (5.9±0.1). Pressure‐volume loop SVL catheter technology was used to evaluate cardiovascular performance in adult birds (controls and following embryonic hypoxia). Hypoxic birds presented a phenotype resembling mammalian left ventricular hypertrophy, with a decreased cardiac output (38660±817), ejection fraction (38.8±0.4) and stroke work (11750±376). We conclude that bobwhite quail are a viable alternative model to study cardiovascular fetal programming.

Grant Funding Source: Supported by NSF & CoMeCyT/CONACYT
Extracellular matrix‐mediated endothelial differentiation of human induced pluripotent stem cells (1152.4)
Authors: Hou Luqia , Huang Ngan
Published: June 2021

Over 8 million Americans are suffering from Peripheral Arterial Disease (PAD), which is due to atherosclerotic occlusion of the peripheral arteries of the limbs. Recent studies suggest that human induced pluripotent stem cell (iPSC)‐derived endothelial cells (iPSC‐ECs) can serve as a promising source for treatment of PAD. However, the low differentiation efficiency of iPSC‐ECs is a major limitation to their clinical use. The purpose of this study was to investigate the role of extracellular matrix (ECM) and cell‐ECM interactions in endothelial differentiation of iPSCs utilizing high throughput ECM microarray technique. We developed a high‐throughput ECM microarray that contains circular printed areas of ECMs on glass slides using a robotic DNA microarrayer. Multi‐component mixtures of purified ECMs components (gelatin, fibronectin, laminin, heparin sulfate proteoglycans, collagen IV, and matrigel) were deposited onto glass slides at fixed distances. A total of 280 spotted matrix features were fabricated with multi‐component mixtures of the ECM components. After dissociating and culturing iPSCs onto ECM microarrays, differentiation was induced by adding VEGF (50ng/ml) for 5 days. EC differentiation was confirmed with CD31 staining, whose expression was scored semi‐quantitatively and averaged among the six replicates on the slide. A greater abundance of CD31 with higher score was observed in ECM features composed of gelatin + laminin + fibronectin tri‐component mixtures comparing to other conditions. Gene expressions of various integrin subunits were compared between iPSCs and iPSC‐ECs to elucidate the role of cell‐ECM interactions. The expression of integrins α1 through α6 and β1 through β4 were elevated in iPSC‐ECs comparing to iPSCs. On the other hand, β5 shows a significant decrease in iPSC‐ECs. In total, this data suggested that ECM differentially promote iPSC differentiation into EC, possibly through binding to various types of integrins.

Grant Funding Source: NIH, NSF, Stanford CVI
Short‐term naproxcinod treatment ameliorates functional muscle ischemia in dystrophin‐deficient mdx mice (1156.1)
Authors: Li Liang , Miglietta Daniela , Thomas Gail
Published: June 2021

Impaired nitric oxide (NO) signaling in the dystrophin‐deficient muscles of patients with Duchenne muscular dystrophy (DMD) and the mdx mouse model of DMD renders the diseased muscles susceptible to functional ischemia, which enhances both fatigue and exercise‐induced muscle injury. We therefore asked if short‐term treatment with naproxcinod, a NO‐donating naproxen, would prevent functional muscle ischemia and restore normal blood flow regulation in the exercising muscles of mdx mice. Norepinephrine (NE) evoked similar decreases in femoral vascular conductance (FVC) in resting and contracting hindlimbs of vehicle‐treated mdx mice, indicating functional muscle ischemia (ΔFVC contraction/rest: 0.93 ± 0.16, n=5). Naproxcinod (40 mg/kg, po) modestly reduced muscle ischemia when given as a single dose and markedly ameliorated it when treatment was extended to 1 wk (ΔFVC contraction/rest: 0.67 ± 0.18 and 0.39 ± 0.08, respectively; n=9 each), while treatment with equimolar naproxen was without effect (n=5). Daily treatment with a lower dose of naproxcinod (20 mg/kg) was equally effective in preventing functional ischemia in mdx and nNOS null mice (ΔFVC contraction/rest: 0.39 ± 0.05, n=10 and 0.31 ± 0.02, n=4, respectively). These findings suggest that naproxcinod’s ability to donate NO rather than inhibit cyclooxygenase is the main mechanism by which the drug improves muscle blood flow regulation in mdx mice.

Grant Funding Source: Supported by DoD, W81XWH‐12‐1‐0256
Antioxidant activity of currently available resuscitation fluids in vitro (1157.5)
Authors: Barr Johnny , Jacobson David , Grubbs Dana , Dubick Michael
Published: June 2021

Addition of antioxidants to resuscitation from hemorrhage reportedly improves outcomes in experimental animals. The present study investigated whether currently available resuscitation fluids have intrinsic antioxidant activity. Direct antioxidant activity of normal saline, hypertonic saline alone or with Dextran, Ringer’s solution alone or with lactate, pyruvate, or β‐hydroxybutyrate, Hextend, Voluven, plasma, 5% albumin and Hyvisc drag‐reducing compounds were investigated in duplicate in systems to either inhibit xanthine oxidase (XO) or superoxide dismutase (SOD) generated oxidant production or measure antioxidant status. N‐acetylcysteine (NAC) was included as a positive control. In the XO system, Hextend showed minor antioxidant activity, whereas Hyvisc preparations, plasma and Ringer’s showed antioxidant activity similar to NAC. All fluids tested inhibited superoxide production in the SOD system about 10% compared to over 30% by NAC. There did not appear to be any significant difference between colloids and crystalloids or compounds such as pyruvate or albumin at the concentrations selected. Taken together these data suggest that currently available resuscitation fluids have minor, if any, intrinsic antioxidant activity. Reported antioxidant properties of these compounds in vivo, most likely reflects indirect activity through their interactions with biological systems.

Grant Funding Source: US Army Medical Research Materiel Command
Regulation of the browning of human white adipose: evidence for sympathetic control and sexual dimorphic responses to sprint interval training (1160.4)
Authors: Scalzo Rebecca , Peltonen Garrett , Giordano Gregory , Binns Scott , Klochak Anna , Paris Hunter , Schweder Melani , Szallar Steve , Wood Lacey , Larson Dennis , Luckasen Gary , Hickey Matthew , Bell Christopher
Published: June 2021

The conversion of white to thermogenic beige adipose tissue has been proposed as an obesity treatment. 3 regulators of this conversion have emerged but information regarding their control is limited. We present 2 studies examining control of these regulators. Study 1: In 10 men, plasma irisin and fibroblast growth factor 21 (FGF21) concentrations were determined prior‐to/during sympathetic activation via hypoxic gas breathing (FIO2=0.11). The measurements were performed twice: with and without sympathetic inhibition (clonidine). FGF21 was unaffected by basal sympathetic inhibition (338±113 vs. 295±80 pg/mL; P=0.43; mean±SE), but was increased during sympathetic activation (368±135); clonidine abrogated this response (269±93; P=0.035). Irisin was unaffected by sympathetic inhibition and/or hypoxia (P>0.21). Study 2: Plasma irisin and FGF21 concentrations, and skeletal muscle protein content of fibronectin type III domain containing 5 (FNDC5) was determined in 19 adults pre/post 3 weeks of sprint interval training (SIT). SIT decreased FGF21 (338±78 vs. 251±36; P=0.046) but did not affect FNDC5 (P=0.79). Irisin was decreased in males (127±18 vs. 90±23 ng/mL; P=0.045) and increased in females (139±14 vs. 170±18). These data suggest a regulatory role of acute sympathetic activation pertaining to the browning of white adipose; further, there appears to be a sexual dimorphic response of irisin to SIT.

Grant Funding Source: Supported by DARPA: N66001‐10‐c‐2134
Differential response of microRNA to contraction in aged and obese mice (1168.4)
Authors: Rice Nicholas , Haran Prashanth , Fielding Roger , Rivas Donato
Published: June 2021

Resistance to anabolic stimuli in skeletal muscle occurs within both aging and obese populations. However, the mechanisms responsible for this ‘anabolic resistance’ are unknown. MicroRNA (miRNA), small (20‐24 nucleotides) post‐transcriptional regulators, have recently been shown to play a role in the response of skeletal muscle to anabolic stimulation. We aimed to compare the response of miRNA to an acute bout of contraction via sciatic nerve electrical stimulation (ES) in skeletal muscle within three groups of C57BL/6 mice aged, 24 wks and fed a control (CON, 10% fat/kcal) or high‐fat (FAT, 60% fat/kcal) diet or aged 124 wks (OLD, 10% fat/kcal). The expressions of miRNA that are known (miR‐378, miR‐27a) and putative (miR‐126, miR‐324) regulators of skeletal muscle development were measured by qPCR at baseline (BL) and after ES. Obesity increased the BL expression of miR‐27a and miR‐324, while miR‐27a and mir‐378 expression was increased with age, compared to CON. After contraction, miR‐126 and miR‐378 were decreased in CON, while miR‐27a and miR‐324 were decreased in FAT. However, the only contraction‐induced change in OLD was a decrease of miR‐378 expression back to control levels. These results illustrate the differential responses of miRNA in skeletal muscle as a result of ES within these distinct groups.

Grant Funding Source: USDA and NIH/NIA
Dual actions of octopamine on heart rate of Crassostrea virginica (1169.1)
Authors: Jean Louis Addy , Carroll Margaret , Catapane Edward
Published: June 2021

Octopamine (OA) is well studied in arthropods. OA’s presence and functions have rarely been reported in bivalves. Previously we found OA present in ganglia and tissues of the oyster Crassostrea virginica. OA was cardio‐acceleratory when applied in situ to animals but cardio‐inhibitory when applied to isolated hearts. We hypothesize the divergent results of OA on heart rate is due to separate actions of OA on visceral ganglia (VG) compared to isolated hearts. We applied OA to VG of animal preparations, with and without transecting the cardiac nerve. We also tested OA on isolated hearts and ventricular muscle strips. We found average basal heart rate of animal preparations was 15 beats/min. Superfusing OA (10‐6 ‐ 10‐3 M) onto animal or VG preparations caused dose‐dependent increases of up to 70%. Applying OA to isolated hearts or heart strips decreased rates to 0. The OA antagonist metoclopramide produced a dose‐dependent blockage of OA actions on animals and heart strips. In animals transecting the cardiac nerve prevented the cardio‐acceleratory effects of OA. The study shows OA affects heart rate in 2 fashions depending on site of application, inhibitory when applied to isolated heart or acceleratory when applied to the animals or VG. At the VG, OA may be stimulating cardio‐acceleratory neurons innervating the heart.

Grant Funding Source: Nih‐2R25GM06003, NYSE 0516041171, NSF‐0622197
Renal cell transplantation reverses PKD progression (1180.22)
Authors: Kelly Katherine , Dominguez Jesus
Published: June 2021

Polycystic kidney disease (PKD, including ADPKD1, ADPKD2, ARPKD) are diseases with overlapping phenotypes and are not curable. They can progress to ESRD, and then the only hope to get off of dialysis is kidney transplantation. We have introduced intravenous renal cell transplantation (IRCT) in rats as an alternative to kidney transplantation, and tested the hypothesis that IRCT with Serum Amyloid A protein (SAA) expressing normal adult renal cells improves structure and function in PKD by coordinating the re‐orientation of adjacent host PKD cells. We tested this idea in the PCK rat, an orthologus model of ARPKD. We included six rat groups starting with surgery at 6 weeks of age and IRCT at 6, 8, and 10 weeks of age, termination was at 26 weeks of age: SA, were sham operated and given SAA negative cells, n=7. SB, were sham operated and given SAA positive cells, n=7. IA, had unilateral renal ischemia for 50 min and given SAA negative cells, n=8. IB, had unilateral renal ischemia for 50 min and given SAA positive cells, n=8. CS, were sham operated PCK rats that did not receive cells, n = 5. CI, were PCK rats subjected to unilateral renal ischemia and did not receive cells. We followed renal function and structure with Dynamic Contrast Enhanced CT (DCE‐CT). Donor cells were found on the cyst walls and damaged tubules. The donor cells were identified 16 weeks post‐transplant by PCR of the SRY (male gene in female kidneys), transferred SAA gene, as well as FISH of the Y chromosome, and by renal genotype revealing mutated (endogenous) and wild type (donor) ARPKD genes. The SAA positive “B” cells drastically improved function and structure and diminished the number of cysts. Transplanted “A” cells also had a positive effect but were less effective than “B” cells. IRCT is an effective means to retard cyst development and progression (all “B” groups significantly different than corresponding “A” groups, p <0.05) in the PCK and has a great potential for PKD therapy.

Grant Funding Source: NIH, DoD, VA
Quantitative label‐free proteomics of tilapia gill epithelium: confirmation of established and identification of novel responses to salinity change (1182.4)
Authors: Li Johnathon , Kültz Dietmar
Published: June 2021

Label‐free quantitative (LFQ) proteomics was employed to analyze effects of salinity stress on the molecular phenotype, i.e. proteome, of gill epithelium in Mozambique tilapia (Oreochromis mossambicus). Fresh water (FW) acclimated tilapia were acclimated to 34 ppt, 70 ppt, and 90 ppt salinity and gill proteins extracted and trypsin‐digested for analysis by LFQ LC‐MS/MS. More than 600 proteins were identified with high identification scores (>85% represented by >5 MS/MS peptides, FDR < 2%). The overall effect of salinity acclimation on protein regulation ratios in gill epithelium (salinity exposed gill epithelia compared to FW handling controls) was found to be proportional to the degree of salinity stress. Salinity‐induced changes in tilapia gill epithelial proteome directly reflected known salinity effects on gills of euryhaline fish, including an increase in the size and number of mitochondria‐rich ionocytes, activities of specific ion transporters, and induction of specific molecular chaperones. Confirming such known effects of salinity on tilapia gill epithelium at the proteome level validated the LFQ workflow. In addition to confirming known salinity stress responses, novel gill proteins involved in salinity acclimation of tilapia, notably protein NDRG1, were identified by this workflow. We propose that protein NDRG1 participates in gill epithelial remodeling during salinity acclimation of euryhaline fish. Moreover, we conclude that LFQ proteomics represents a powerful tool for gaining deep insight into effects of environmental salinity stress on the molecular phenotype of osmoregulatory tissues in euryhaline fish. Supported by NSF grant IOS‐1049780.

Grant Funding Source: NSF IOS‐1049780
α‐Glucosidase inhibiting activity and antioxidant properties of grape pomace extracts (134.5)
Authors: Kadouh Hoda , Sun Shi , Zhou Kequan
Published: June 2021

While grape pomace contains considerable amounts of polyphenols, dietary antioxidants have been associated with a reduced risk of type 2 diabetes. We have previously reported strong α‐glucosidase inhibition exhibited by red wine grape pomace extracts, implying a potential role in diabetes management. In the current study, we aim to understand the relationships between this activity and antioxidant capacity of these extracts. Chambourcin, Merlot, Norton, Petit Verdot, Syrah and Tinta Cão red wine grape pomaces extracted with 50% acetone were evaluated for antioxidant properties via common antioxidant assays. At 2 mg/ml, Merlot, Syrah and Tinta Cão appeared to have the highest respective total phenolic content expressed as 0.29, 0.28 and 0.26 mg gallic acid equivalents/ mg extract. At 5 mg/ml, Chambourcin, Merlot and Tinta Cão exhibited the highest DPPH radical scavenging capacity, at 58%, 51% and 49%, respectively. At 0.1 mg/ml, Tinta Cão exceeded all other varieties in oxygen radical (AAPH) absorbing capacity, at 4878 uM trolox equivalents/ g extract. A strong positive correlation was observed between these results and our previous findings of 95%, 88% and 85% α‐glucosidase inhibition exhibited by Tinta Cão, Syrah and Merlot pomace extracts, respectively. Results were significant, suggesting that the α‐glucosidase inhibiting potency of grape pomace extracts may be related to their richness in antioxidants.

Grant Funding Source: Supported by the United States Department of Agriculture
Towards a comprehensive view of the neural‐electrode tissue interface: image analysis for neural engineering applications (153.8)
Authors: Kolarcik Christi , Lesniak Andrew , Castro Carlos , Demetris Anthony , Gaunt Robert , Cui X.
Published: June 2021

Biocompatibility issues limit the longevity of neural interfacing devices designed to restore sensory‐motor function. However, a comprehensive systems‐level understanding of the device‐tissue interface is lacking. We combined immunohistochemistry, high‐resolution digital slide scanning and computational image analyses to evaluate the response associated with floating microelectrode arrays implanted into feline dorsal (sensory) or ventral (motor) lumbosacral roots (n = 16 animals; 2 implants/animal). Paraffin‐embedded sections were stained with a variety of chemical (hematoxylin/eosin, Nissl/Luxol fast blue) and antibody‐based [NF200 (axons), S100 (Schwann cells), vimentin (fibroblasts, endothelial cells, astrocytes), NeuN (neuronal nuclei), caspase‐3 (apoptotic cell death), MAC387 (monocytes/macrophages), GLUT1 (glucose transporter)] stains. Digital images were analyzed using NearCyte software. Intensity of the inflammatory reaction as a function of distance from the electrode‐tissue interface was quantified. Neural degeneration in the spinal cord proximal and distal to the site of array implant was compared to the contralateral, non‐implanted side. Neuronal density and nearest neighbor relationships were mapped and electrode performance metrics considered. This work provides a more comprehensive, quantitative profile of the neural electrode‐tissue interface. Ongoing work aims to incorporate multiplexed immunohistochemistry such that more in‐depth social interactions can be assessed in the context of the tissue architecture.

Grant Funding Source: Supported by DARPA Contract N66001‐11‐C‐4171.