bluuebunny/crossref_metadata_2025 huggingface dataset:
Work in the Cold: A Systematic Review of How the Chronic Exposure to Low Temperatures May Explain Painful Soft Tissue Disorders
Authors: Remigio Wilton , Trygar Michael Y , Schweiger Jacob , Fairchild Mary
Published: June 2021

Movement disorders presenting with pain carry a significant economic and rehabilitative burden which is more predominantly in the working age population. Amongst the many causative factors suggested, cold exposure has been implicated as an important, albeit, unrecognized etiology in the development of painful movement related conditions. To this date no reviews have focused on the effects of cold exposure and its association with the appearance of musculoskeletal pain. The purpose of this systematic review aims to delineate and characterize this relationship.

An electronic search was conducted using PubMed, Google Scholar, Academic Search Premier, and Oxford Journals. The following search terms were used to conduct this study: “Cold exposure and musculoskeletal injury” “Cold and injury risk” “Cold climate and workplace injury” “Cold exposure and pain” “Cold and arthritis”, “Cold physiology” “Effects of cold on musculoskeletal disorders” “ Effects of cold on pain perception” “Effects of cold exposure on injury risk” “Musculoskeletal manifestations and diseases due to environmental cold exposure.” A hand search of each reference list was performed to improve the quality of the literature review. Fourteen relevant articles were gathered from the literature review and used in this study.

A consistent relationship between cold environment exposure and painful somatic manifestations was noted throughout the literature in the past 15 years. The most frequently reported manifestations included low back pain, finger pain, shoulder pain, neck pain as well as diagnoses of epicondylitis, tenosynovitis, and peri‐tendonitis. This relationship was stronger in subjects exposed to cold environments in their workplace when compared to controls. Chronic cold exposure in workplace environments appears to be a primary determinant in the etiopathogenesis of painful disorders affecting the body with important implications for productivity and work enjoyment.

Support or Funding Information

MIsericordia University

College of Health Professions and Education

Physical Therapy Department

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Inhibition of the RNA binding protein HuR protects against cardiac ischemia/reperfusion injury by reducing inflammatory gene expression
Authors: Slone Samuel , Fleifil Salma , Anthony Sarah , Green Lisa , Nieman Michelle L , Lorenz John , Tranter Michael
Published: June 2021

Despite medical advances, cardiac ischemia/reperfusion (I/R) injury remains a leading cause of morbidity and a huge economic burden in the United States. RNA binding proteins are becoming recognized as potential mediators of cardiac physiology and pathology, but the role of HuR, an RNA binding protein highly expressed in myocytes, in acute cardiac I/R injury is unknown. HuR has been shown in other tissues to be a critical post‐transcriptional mediator of pro‐inflammatory chemokine and cytokine gene expression, and our lab has shown HuR to be activated (nuclear‐to‐cytoplasmic translocation) in cardiomyocytes 2 hours post‐ischemia/reperfusion injury.

To address the functional role of HuR in I/R, cardiomyocyte‐specific HuR deletion mice (iCM‐HuR−/−) were subjected to 30 minutes of LAD (left anterior descending) coronary artery ligation followed by 24 hours of reperfusion. In parallel, a separate group of wild‐type mice were subjected to 30 minutes ischemia with a pharmacological inhibitor of HuR given just prior to reperfusion. Analysis of infarct size showed a smaller infarct with both HuR genetic deletion (41% infarct/risk in iCM‐HuR−/− vs. 51% infarct/risk in control, N=3, P<0.05) and pharmacological inhibition (~11% decrease in infarct size compared to vehicle, N=4, P=0.069). We were also able to recapitulate this protection in vitro using neonatal rat ventricular myocytes (NRVMs) and H9C2s (myoblast derived rat left ventricular cardiomyocytes) subjected to 6 hrs of simulated ischemia (glucose deprivation and hypoxia at ≤1% O2) followed by 2 or 24 hrs of reperfusion (reoxygenation and reintroduction of glucose/serum) by showing that siRNA‐mediated knockdown or pharmacological inhibition of HuR significantly reduced cell death and caspase‐3 activation. Analysis of inflammatory gene expression demonstrates a significant blunting of IL‐6 expression at just two hours post‐reperfusion both in vivo and in vitro, suggesting that HuR activity is necessary for the early induction of inflammatory gene expression networks.

In conclusion, our results suggest that inhibition of HuR is protective against cardiac I/R injury through a reduction in inflammatory gene expression. Work is still ongoing to identify the specific means by which HuR is activated and mediating expression of inflammatory cytokines and chemokines.

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
PPARα interacts with PHD proteins on Renal Fibrosis in a Mouse Unilateral Ureteral Obstruction Model of Chronic Kidney Disease
Authors: Choi Myung , Oyekan Adebayo
Published: June 2021

Peroxisome proliferator activated receptor (PPAR)α and prolyl hydroxylase domain‐containing protein (PHD), “sensors” of cellular energy and oxygen have protective effects in the kidney and potentially act in a complimentary fashion but the mechanisms involved are not fully known. This study examined the effects of PPARa and its interaction with PHD in a mouse model of renal fibrosis induced by unilateral ureteral obstruction (UUO). UUO increased hydroxyl proline in PPARa WT and KO kidneys (P<0.05) but to a greater extent in KO kidneys. Dimethyl oxallyl glycine (DMOG), a PHD inhibitor, markedly blunted the effect only in WT kidneys (P<0.05). TGFβ expression was also increased (~ 3‐fold, P<0.05) in both WT and KO kidneys. However, DMOG blunted UUO‐induced increase in TGFb expression only in WT kidneys (P<0.05). Bilirubin, an index of heme oxygenase activity, was lower in KO kidneys at basal level (P<0.05) and was reduced in WT kidneys (P<0.05) following UUO but paradoxically increased in KO kidneys (P<0.05). DMOG blunted the reduction in bilirubin in WT (P<0.05) but was without effect in KO kidneys. Serum arginase activity, an index of cellular content of L‐Arginine, was increased in WT mice (P<0.05) but there was no change in KO mice following UUO. DMOG abolished the effect in WT but not KO mice. These data suggest that PPARα plays a protective role against UUO that appears to be coupled to PHD proteins by mechanisms related to heme oxygenase and arginase.

Support or Funding Information

This study was supported by the National Institutes of Health grant G12MD007605.

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
The stable and unstable function of Bioenergy, in the immunological and neuronal environment of cancer, viral infection and bacteria
Authors: Einstein George P , Tulp Orien L , Konyk Carla M , Rahman Michael S
Published: June 2021

There has been long established that biophysical & biochemical reactions in the cellular communication of neuronal messaging. Specific Quantum Photonics Energy have been shown to stimulates these Biophysical/Biochemical Reactions. Systems Biology model representing regulation.

Biophotonics therapy uses the harnessing and application of light for immune stimulation and antibacterial and antiviral properties.

Biophysical Neural Networks examines the interface between systems theory and experiment at a multi‐hierarchical level of neural organization.

The Immune stimulation matrix may be understood as a interplay of the milieu of the biochemical and physical parameters that ultimately move the organism to health and homeostasis, or to disease. The GP Einstein model of Coherence – Congruence can be used to understand the parameters and relations that have been obtained from previous independent experiments using specific quantum photonic energy conducted at Einstein Medical Institute. The experiments have included published applications of treatment of HIV/HVC therapy.

This stability model can them be used to predict immunological phenomenon as a summation towards regulation or not and can further the impetus to design corresponding experiments.

Support or Funding Information

Supported by Institutional Resources of USAT, UHH, and EMI

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
HEPATIC REGENERATION INDICES AND BEST PERIOD POST 70% HEPATECTOMY TREATMENT: AN EXPERIMENTAL MODEL
Authors: DE ARAUJO OLIVEIRA LUZ MARINA GONÇALVES , LEME PEDRO LUIZ SCHILACCI , CHAVANTES MARIA CRISTINA G
Published: June 2021

BACKGROUND

Hepatic regeneration represents a protection mechanism against the loss of hepatic tissue functional or by partial hepatectomy.

OBJECTIVES

The present study analyzed morphological, histomorphometric and immunohistochemical characteristics for monitoring hyperplasia and hypertrophy liver regeneration in rats post partial hepatectomy as same as the best time regeneration.

METHODS

Twenty‐eight male adult Wistar rats were divided into four groups: Sham (SG), 3 (H3), 7 (H7) and 14 (H14) days, according to observation time post surgical procedure. The Sham group underwent just to laparotomy. The groups H3, H7 and H14 underwent to 70 % partial hepatectomy. According to each time treatment each group were euthanized. The regenerated livers were removed and were submitted to morphological calculations (weight, volume and hepatosomatic index), histomorphometric (mitotic index and quantification by PAS) and immunohistochemical analysis (quantification of mitosis by PCNA).

RESULTS

There were no statistical differences in the morphological indices after the experimental period. There were differences of the Mitotic Index among the sham group and the three study groups. Comparing to H14 group in the percentage of positive area for PAS were not found differences among the sham, H3 and H7 groups. The Hepatocyte Proliferation Index showed differences by immunohistochemical study among to the sham group, comparing to the three study groups.

CONCLUSION

The histomorphometric and immunohistochemical indices showed the importance for the liver regeneration process, by the number of mitosis and the hepatic glycogen presence. The best regeneration time were in 7 days, due to the positive correlation into all indices.

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Leptin Induced Satiety and the Contribution of Brainstem Astrocytes
Authors: Stein Lauren , Lhamo Rinzin , Cao Anh , Tinsley Ian , Doyle Robert , Hayes Matthew
Published: June 2021

The staggering prevalence of obesity worldwide poses major public health concerns. Since energy balance regulation is coordinated by CNS centers, investigation into the underlying homeostatic, brain mechanisms controlling feeding behavior and weight management is critical to the development of novel and efficacious obesity therapeutics. While the vast majority of studies have investigated neuronal processing of satiety hormone signaling, little is known about the contribution of non‐neuronal cells such as astrocytes. Using fluorescent in situ hybridization we observed colocalization of fluorescently labeled leptin (Cy5‐lep) on both human and rodent brain stem astrocytes that express the leptin receptor (LepRb). These findings suggest that brainstem astrocytes are involved in leptin mediated energy balance control. To test this hypothesis, rats maintained on chow or high fat diet (HFD) for 4 weeks were pretreated with vehicle or 5nmol fluorocitrate (FC; transient inhibitor of astrocyte metabolism) followed by vehicle or 5μg/μL leptin (all administered into the 4th ventricle). FC pretreatment significantly attenuated 24h hypophagic and body weight suppressive effects of leptin in chow‐ but not in HFD‐maintained rats. Collectively, these findings support the hypothesis that DVC astrocytes express LepRb and acts as critical modulators of the anorectic effects of leptin ‐ an effect that is blunted in HFD‐induced obesity and may contribute to the perpetuation of obesity. Further experiments are underway to investigate the direct action of leptin signaling on DVC astrocytes to promote satiety.

Support or Funding Information

NIH NIDDK R01DK116762 NIH NIDDK F32DK118818 TOS Early Career Fellowship

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
The Role of Respiratory Noradrenergic Neurons Projecting to the Basal Lateral Amygdala in Anxiety‐related Behavior
Authors: Martinez Vena , Sun Jenny , McKinney Andrew , Jiang Xiaolong , Ray Russell
Published: June 2021

The most commonly reported symptom of panic attacks is respiratory dysfunction, such as hyperventilation. It has been shown that subsets of patients with anxiety disorders show a lower threshold for carbon dioxide level imbalances and exposure to high levels of carbon dioxide (hypercapnia) can induce anxiety‐like behavior such as panic attacks. The false suffocation alarm hypothesis posits that inappropriate activation of respiratory chemoreceptors in response to benign indices triggers an alarm of suffocation danger and may contribute to anxiety and panic disorders. Two potential candidates that may link anxiogenic and respiratory circuitry are the central noradrenergic (NA) system and the amygdala, both of which have been shown to play roles in both breathing and anxiety. Therefore, we hypothesize that projections from the brainstem NA nuclei to the amygdala play a functional role in modulating the hypercapnic ventilatory response and anxiety‐like behavior in mice.

To test this hypothesis, we targeted NA projections to the amygdala by using a Cre‐expressing retrograde virus applied to the amygdala of our intersectional DBH‐p2a‐FLPo; RR5, multicolor reporter line to conduct projection mapping of NA neurons to the amygdala and DBH‐p2a‐FLPo; RR1 and RR2 DREADD mice to specifically inhibit or stimulate NA neurons that project to the amygdala. In these mice, we measured respiratory output using whole‐body plethysmography and anxiety‐like behavior using open field, light dark, and elevated plus maze.

Preliminary results indicate that DREADD mediated inhibition of NA neurons projecting to the amygdala may result in a decreased hypercapnic ventilatory response. However, upon stimulation of the NA neurons that project to the amygdala, there was no change in the hypercapnic ventilatory response. Inhibition and stimulation of NA neurons projecting to the amygdala result in a possible decrease in anxiety‐like behavior. Our preliminary results demonstrate the feasibility of delineating and accessing NA neurons based on the their projection target and suggest that NA neurons that project to the amygdala may play a role in the hypercapnic ventilatory response, as well as anxiety‐related behavior. Future directions will include the role of amygdala‐projecting NA neurons in behavior, such as fear learning and anxiety‐related behavior, under higher CO2 concentrations.

Support or Funding Information

McNair Medical Institute

R01HL130249

R01HL130249‐02S1

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
5‐hydroxymethyl‐2‐furfural (5HMF) Improves Exercise Capacity During Normoxia and Preserves Cardiovascular Function During Severe Hypoxia in Exercising Swine
Authors: Williams Brian T , Ciarlone Geoffrey E , Mahon Richard T , Swift Joshua M
Published: June 2021

BACKGROUND

Modern military operations at high altitudes >5,000m result in reduced warfighter performance due to a lack of acclimatization. The exercise performance decrements are attributed to acute exposure to hypobaric hypoxia (HH), characterized by reduced arterial oxygen content and oxygen tissue delivery. The compound 5‐hydroxymethyl‐2‐furfural (5HMF), facilitates oxygen binding to hemoglobin (HgB) at low FiO2. Recent swine experiments in our lab demonstrated that 5HMF can increase oxygen‐HgB affinity, reduce cardiopulmonary decrements, and improve survival time during normobaric hypoxia (10% FiO2) exposure. The experiment determined if prophylactic treatment with 5HMF would mitigate hypoxia‐dependent decrements in exercise performance.

METHODS

Castrated Yorkshire swine (30–35kg, n=9) completed a one week treadmill familiarization protocol, followed by a baseline maximal exercise test (BET) consisting of staged increases in speed at a fixed 19% grade. Animals were randomized to receive IV infusion of either normal saline (VEH) or 5HMF (20mg/kg; 2hrs pre‐testing) and completed two additional maximal exercise tests during exposure to normoxic air (21% FiO2) (NET) and hypoxia (12% FiO2) (HET) on successive days. The same three tests (BET, NET, and HET) were completed the following week with the other IV treatment not used during the first testing week, allowing each animal to serve as its own control. Physiological parameters collected included cardiovascular and exercise performance during baseline, exercise, and recovery phases.

RESULTS

HET led to ~40% lower total exercise time compared to both normoxic tests [BET (p=0.001) and NET (p=0.001)] regardless of treatment. During NET, 5HMF resulted in a 7% greater peak workload (METS) than BET (p=0.02) that was not seen with VEH (p=0.07). During HET, 5HMF resulted in a similar mean workload as VEH (p=0.6), but reduced peak heart rate by 12% (p=0.04, n=4). Average heart rate during recovery from HET was 6% lower in swine administered 5HMF compared to recovery following NET (p=0.02).

CONCLUSIONS

This study developed an exercise model in swine exposed to acute hypoxia that reliably reduced exercise performance. Using our model, we observed that 5HMF increased exercise capacity under normoxic conditions and preserved cardiovascular function during and immediately after exercising in severe hypoxic conditions. This work further demonstrates the utility of using an oxygen‐HgB affinity increasing compound (5HMF) to improve operational effectiveness and capabilities in high altitude environments without the need for prior acclimatization.

Support or Funding Information

Office of Naval Research, USUHS Grant, HU0001‐14‐1‐0008

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Adverse Effect of Luteolin on the Anticancer Ability of Oxaliplatin in HCT116 Human Colorectal Carcinoma Cells
Authors: Jang Chan Ho , Moon Nayoung , Oh Jisun , Kim Jong‐Sang
Published: June 2021

Colorectal cancer (CRC) is one of the most frequently diagnosed cancers in the world. Intracellular oxidative stress by accumulation of reactive oxygen species (ROS) can cause redox imbalance that is associated with higher risks of cancer development. Dietary flavonoids activating a nuclear factor E2‐related factor 2/antioxidant response element (Nrf2/ARE) signaling pathway have received a lot of attention due to their abilities to reduce oxidative stress by expressing antioxidant/phase II detoxifying enzymes. Hence, some cancer patients taking chemotherapeutic agents have been consuming flavonoid‐rich food, expecting their anticancer efficacies to be synergistically enhanced. However, careful consideration of possible undesired effects of flavonoid intake during chemotherapy is needed; flavonoids activating Nrf2/ARE signaling pathway could favor cancer cell survival by attenuating ROS‐induced oxidative stress elevated by anticancer agents. The purpose of the present study was to examine how luteolin would affect chemotherapeutic activity of oxaliplatin, a commonly used anticancer agent for colon cancer, in HCT116 p53+/+ cell line and its derivative HCT116 p53−/− cells. Results showed that luteolin increased ARE‐luciferase activity, decreased ROS level by Nrf2/ARE activation and subsequently stimulated proliferation of oxaliplatin‐treated colorectal cancer cells. In addition, oxaliplatin and a high dose of luteolin induced cell cycle arrest and apoptosis in a p53‐dependent manner, respectively. However, oxaliplatin‐induced cell cycle arrest was compromised by the high dose of luteolin in HCT116 p53+/+ cells. Moreover, the high dose of luteolin suppressed oxaliplatin‐induced p21 expression in HCT116 p53+/+ cells, but not in HCT116 p53−/− cells. Current observations indicate that a high dose of luteolin can negatively affect oxaliplatin‐based chemotherapy in a p53‐dependent fashion, suggesting that Nrf2‐activating flavonoids may interfere with chemotherapeutic efficacy of anticancer agents in colorectal cancer cells that carry functional p53 protein. Further studies about its in vivo impact of luteolin on oxaliplatin‐based chemotherapy are needed to ascertain current findings.

Support or Funding Information

This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Ministry of Science and ICT (MSIT), Republic of Korea.

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Protective Effect of Steamed Soybean Wastewater Against Intestinal Inflammation
Authors: Jeong Soojung , Averilla Janice Nullan , Moon Nayoung , Jang Chan Ho , Lim Ji Sun , Oh Ji Sun , Kim Jong‐Sang
Published: June 2021

Steamed soybean wastewater (SSW) is a commonly produced as a byproduct for manufacturing soybean food such as chonggukjang, doenjang, and natto, and may contain various water‐soluble and biologically beneficial constituents. In this study, we examined the general composition of SSW and additionally the protective effect against colorectal damage caused by dextran sodium sulfate (DSS) in adult male BALB/c mice. The moisture content in the SSW was 90.8±0.42%, crude protein 1.2±0.02%, crude lipid 0.13±0.01%, crude protein 0.85±0.05%, carbohydrate 7.02±0.32%. For animal study, the lyophilized SSW was dissolved in vehicle (consisting of 5% v/v ethanol, 5% v/v tween‐80, and 90% saline) and orally administered at a dose of 1 g/kg body weight on a daily basis for three weeks. Colorectal damage was induced by providing 3.5% (w/v) DSS in drinking water for the last nine days. We found that oral administration of SSW macroscopically and histologically improved DSS‐induced colorectal injury, reduced expressions of inflammatory cytokines and NF‐κB and its downstream proteins in the colorectal tissue, and decreased molecular markers of oxidative DNA damage (assessed by the plasm level of 8‐OHdG) and lipid peroxidation (measured by the MDA level in liver homogenate). These results suggest that dietary SSW can ameliorate colorectal damage by attenuation of inflammatory response.

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Impact of Developmental Nicotine Exposure on Cholinergic Airway Signaling
Authors: Rivera Benjamin D , Borrero Nathan G , Cross Seres J.B. , Fregosi Ralph F , Boitano Scott
Published: June 2021

In 2014, 8.4% of US women reported smoking during pregnancy. Conservatively, this translates into approximately 360,000 smoke‐exposed infants born in 2015 in the United States. Fetal nicotine exposure alters cholinergic signaling through activation of Nicotinic Acetylcholine Receptors (nAChRs) in the developing lung and nervous system. Altered expression of nAChRs can persist and result in lasting changes in lung function. The impact on airway nAChRs, which can influence ion transport to control the airway surface liquid layer and mucociliary clearance, remains poorly defined. Here we begin to discern the impact of an acute nicotine challenge on airway epithelial signaling by evaluating the tracheae of animals exposed to nicotine in utero and after birth (developmental nicotine exposure, DNE) and controls (saline exposed sham). Tracheae were excised from neonate rats between post‐natal days 7 – 12 and were mounted in Ussing Chambers to measure transtracheal resistance (TTR) and short circuit current (Isc) in response to nicotine. The resting TTR in DNE animals trended lower than that in sham‐treated animals. Additionally, it was found that compared to sham, tracheae from DNE‐treated animals displayed significantly larger peak Isc in response to nicotine. Isc experiments of whole neonate tracheae in the presence of epithelial Na+ channel (ENaC), Ca‐induced Cl Channel (CaCC) or CFTR Channel inhibitors (amiloride, DIDS and CFTRinh‐172, respectively) suggest that the bulk of the peak Isc is mediated by CaCC secretion in response to the Ca2+ influx triggered by activation of nAChRs. Preliminary experiments to evaluate changes in nAChR subunit expression between DNE and control animals using mRNA extraction and qPCR suggest altered subunit expression in the DNE‐treated animals. In summary, we report the first Ussing Chamber recordings from rat neonate tracheae and demonstrate significant changes in Isc following DNE. These data highlight the potential physiological changes of early life exposure to nicotine, independent of cigarette smoke.

Support or Funding Information

National Institutes of Health Grants: NIEHS/SBRPP ES094940 (SB), NIEHS/EHS‐TRUE ES025494 (NGB), NICHD HD071302

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Loss of lipoprotein receptor LRP1 ablates neural stem cell migration to ischemic lesions
Authors: Sayre Naomi , Kokovay Erzsebet
Published: June 2021

Brain damage due to stroke is a leading cause of death and long‐term disability in the US. Treatment options are limited, necessitating a better understanding of reparative and pathological processes after stroke. Ischemia stimulates the proliferation and migration of neural stem cells (NSCs) from the subventricular zone toward the ischemic lesion in mice. During this time, the migrating NSCs differentiate into GFAP positive cells and pro‐reparative glia. While the importance of this process is not fully elucidated, it is clear that limiting NSC response increases lesion size and worsens behavioral outcomes after ischemic stroke. We tested the effect of low‐density lipoprotein receptor related protein 1 (LRP1) on modulating NSC response and differentiation, and found that virtually every aspect of NSC physiology we tested was altered after deletion of LRP1; increased glial differentiation, proliferation, and self‐renewal were measured. After middle cerebral artery occlusion in mice, we observed a marked reduction in the migration of neuroblasts toward the site of the lesion, which correlated with increased gliosis and worsened behavioral outcomes. Loss of LRP1 also caused reduction in expression of the chemokine receptor CXCR4, which could account for the loss of migration. Ongoing studies involve elucidating the mechanism by which LRP1 regulates CXCR4 expression as well as understanding the effect on pro‐reparative processes after stroke.

Support or Funding Information

This research is supported by a pilot grant from the William and Ella Owen's Medical Research Foundation, and a Veteran's Health Administration Career Development Award K2BX003240.

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Human Blood Serum Impacts Permeability of the Blood‐Brain Barrier in a Sex‐ and Age‐ Dependent Manner
Authors: Ho Dao H , Gay Elaine A
Published: June 2021

The blood‐brain barrier (BBB), a semi‐permeable fence between the brain and the blood, maintains homeostatic balance of substances entering and leaving the brain. In the last decade, the causes and consequences of BBB dysfunction have been recognized as the central component of the development and progression of brain‐related illnesses such as Alzheimer's disease (AD), multiple sclerosis (MS), and schizophrenia (SCZ). In these disorders, pathologic BBB leakiness is often caused by changes in the local cellular milieu on the brain‐side as well as on the blood‐side of the BBB. On the brain‐side, injury to neurons, astrocytes, microglia, and pericytes can lead to BBB leakiness, while on the blood‐side, pathophysiologic levels of circulating factors such as hormones, inflammatory cytokines, and immune cells can significantly alter BBB permeability. The goal of this study was to test whether blood serum, which reflects the circulating milieu in the body, can directly alter BBB integrity. We tested the hypothesis that blood serum of patients with secondary progressive multiple sclerosis (SPMS) will increase BBB permeability compared to healthy controls.

To test the direct impact of blood serum on BBB integrity, we used three‐dimensional Neurovascular Units (3D NVUs). This in vitro model of the BBB integrates endothelial, neuronal, astrocytic, and microglial cells into a three‐dimensional platform, that allows for the assessment of transendothelial electrical resistance (TEER, Ω cm2). Blood serum of four SPMS patients (two men, two women) and four matched healthy controls (two men, two women) were purchased from PrecisionMed, Inc., and diluted to 40% with cell culture media for testing. TEER was recorded immediately prior to serum exposure (baseline), and again at 24 hours after serum treatment. TEER values were normalized to baseline prior to analysis. The protein levels of 100 different serum cytokines were measured in undiluted serum samples using the Human Cytokine Proteome Profiler (R&D Systems).

Stepwise multiple regression analysis revealed that age and sex of the individual were strong predictors of the change in TEER, with serum from female and younger individuals inducing a greater change in TEER (R2=0.81, p=0.01). Presence of SPMS, and levels of cytokines were poor predictors of BBB permeability as measured by TEER. This preliminary study demonstrates that the 3D NVU may be a useful tool in future investigations of the effects of blood serum on BBB integrity.

Support or Funding Information

This project was funded by the TATRC AMEDD Advanced Medical Technology Initiative grant. The views expressed in this abstract are those of the authors and do not reflect the official policy or position of the Department of the Army, Department of Defense, or the U.S. Government.

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Hypothalamic C2‐domain protein (C2CD5) involved in protein trafficking and food intake
Authors: Gavini Chaitanya , Cook Tyler , Mansuy‐Aubert Virginie
Published: June 2021

Rates of overweight and obesity epidemic have risen significantly in the past few decades, and 34% of adults and 15–20% of children and adolescents in the United States are now obese. Melanocortin receptor 4 (MC4R), contributes to appetite control in hypothalamic neurons and is a promising target for anti‐obesity treatments or drug development. While the presence of functional MC4R is crucial for normal neural control of homeostasis and is altered in obesity and in presence of lipids, the mechanisms underlying altered MC4R trafficking are unknown.

Our studies identified a novel C2‐domain protein, C2CD5 that appears to contribute to the regulation of MC4R trafficking. We found that 1) the expression of C2CD5 is decreased in diet‐induced obesity models compared to controls, 2) C2CD5 knock‐out mice exhibit pronounced obesity partially due to an increase in food intake compared to control mice when fed a high‐fat diet, 3) C2CD5 colocalize and interacts with MC4R complex, 4) loss of functional C2CD5 alters MC4R endocytosis, and, 5) C2CD5 knock‐out mice exhibit decreased acute responses to Melanotan‐II injection into the paraventricular hypothalamus.

Based on these, we hypothesize that hypothalamic C2CD5 is a MC4R trafficking protein that responds to metabolic cues and is involved in neural control of energy balance. These studies provide evidence for a novel pathway and targets, to develop therapeutic drugs potentially to rescue energy balance defects that contribute to the development and maintenance of obesity.

Support or Funding Information

This study was supported by AHA SDG and Loyola University Chicago to VMA.

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
The Role of Vagal Free Fatty Acid Receptor 3 (FFAR3) in FMT Improvement of Glucose Homeostasis
Authors: Cook Tyler , Bonomo Raiza , Gavini Chaitanya , Gautron Laurent , Layden Brian , Mansuy‐Aubert Virginie
Published: June 2021

More than 100 million Americans are obese, representing over 35% of the Unites States population. Western diet (WD) is a major cause of the obesity epidemic, and it increases prevalence of many other comorbidities, particularly Type II Diabetes. The western diet consisting of high saturated fat, high cholesterol, high sugar, and heavily processed foods robustly disrupts the composition of the gut bacteria. The microbiome ferments non‐digestible fibers to release short chain fatty acids (SCFA's) which serve as major energy substrates as well as potent signaling molecules through free fatty acid receptors 2 (FFAR2) and 3 (FFAR3). Gut dysbiosis has been associated with changes in SCFA levels that correlate with obesity in humans and mice. The SCFA's propionate and butyrate bind FFAR3 with high affinity, and FFAR3 signaling has been shown to modulate energy expenditure through sympathetic nervous system activation. The role of FFAR3 in the parasympathetic nervous system control of glucose homeostasis is currently unexplored. The vagus nerve primarily consists of sensory afferents which relay specific nutrient information from the periphery to the brain. Several studies have shown that disruption of the vagus nerve eliminates effects of the microbiome and SCFA's altering metabolism, yet the molecular mechanisms of this communication remain largely unknown. We have found that western diet alters SCFA profiles, which have been shown to modulate glucose homoeostasis and energy expenditure in a vagus nerve dependent manner. Furthermore, FFAR3 expression was reduced in the cell bodies of the vagus nerve after WD feeding. We confirmed previous findings that fecal microbiome transplantation (FMT) from lean mice reversed some WD‐induced changes to bacterial composition, plasma SCFA's, and glucose homeostasis. Our data suggest that altered FFAR3 signaling in vagal afferent neurons may contribute to some of the metabolic changes seen upon western diet feeding, and that gut microbes transplanted from lean to obese mice may improve glucose homeostasis through SCFA's binding FFAR3 in the vagus nerve.

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Effects of CO2 on Regional Cerebral Blood Flow Regulation During Lower‐Body Negative Pressure
Authors: Thrall Scott F , Green Chantelle , Wynnyk Kristi , Brandt Rachelle , Day Trevor
Published: June 2021

Cerebrovascular CO2 reactivity (CVR) is differentially regulated between anterior and posterior cerebral circulations, where the cerebrovasculature is responsive to increases (dilation) or decreases (constriction) in arterial CO2. In addition, anterior and posterior cerebral blood flow (CBF) may be differentially regulated during lower body negative pressure (LNBP), where blood volume distribution is experimentally moved toward the lower extremities, imposing an acute hypovolemic and hypotensive challenge. However, the effects of steady‐state increases and decreases in CO2 on the CBF response to LBNP‐imposed hypotension has not been investigated systematically. The aim of this study was to investigate regional CBF responses to incremental (i.e., ramp) LBNP in steady‐state hypo‐ and hypercapnia in anterior and posterior cerebral circulations. We hypothesized that posterior CBF would be better maintained during LBNP at all levels of CO2 and that regional patterns of CBF regulation during LBNP would be unchanged by steady‐state CO2 perturbations. In 14 healthy participants, we measured cardiovascular and cerebrovascular variables, including heart rate (HR; ECG), mean arterial pressure (MAP; finometry), and using transcranial Doppler ultrasound, cerebral blood velocity (CBV) and cerebrovascular conductance (CVC; CBV/MAP) in the middle (MCA) and posterior cerebral artery (PCA). We carried out three separate incremental LBNP protocols (−20, −40, −60 and −80 mm Hg; 3‐min each) at three randomized steady‐state levels of CO2: (a) hypocapnia (−8 mm Hg; i.e., coached hyperventilation), (b) normocapnia (i.e., room air), and (c) hypercapnia (+8 mm Hg; 5% inspired CO2). We found that HR increased incrementally with LBNP in all CO2 conditions (P<0.001). At −80mmHg LBNP, MAP decreased in hypo‐ (P=0.046) and normocapnia (P=0.002). MCA CBV decreased in normo‐ (P<0.001) and hypercapnia (P<0.001). PCA CBV also decreased in normo‐ (P=0.011) and hypercapnia (P=0.002). However, MCA CVC decreased in normo‐ (P=0.01) and hypercapnia (P<0.001), whereas PCA CVC did not decrease during LBNP at all levels of CO2. These findings demonstrate greater sensitivity in anterior cerebral circulation compared to posterior during a moderate LBNP challenge with alterations in CO2. Our data elucidate a comprehensive understanding of regional CVR during LBNP‐induced hypovolemia, and may be applied to understanding preferential protection of posterior brain structures during hypovolemic shock.

Support or Funding Information

NSERC Discovery and MRU Faculty of Science and Technology

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
The Acute Effect of Hyperglycemia on the Exercise Pressor Reflex
Authors: Huo Yu , Grotle Ann‐Katrin , Ybarbo Kai M , Stone Audrey J
Published: June 2021

Previous work has shown that the exercise pressor reflex is exaggerated in type 2 diabetic rats that present with hyperglycemia. Although it is likely that chronic hyperglycemia plays a role, no studies have isolated the acute effects of high blood glucose levels on this reflex. Therefore, the purpose of the current study was to determine the acute effects of hyperglycemia on the exercise pressor reflex. We first determined the glucose concentration needed to increase local blood glucose level in the hindlimb vasculature to a similar level seen in our type 2 diabetic rats that had an exaggerated exercise pressor reflex. To do this, healthy Sprague‐Dawley rats were infused over 20 min with one of two different concentrations of glucose (125 mg/ml, male n=3 or 250 mg/ml, male n=3) into the arterial supply of the left hindlimb with blood flow to and from the hindlimb restricted. At the same time somatostatin (3.9 ug/100 ul) was infused systemically in order to prevent an endogenous insulin response. Blood glucose was measured every two minutes from both hindlimbs to determine how long it would take to bring blood glucose concentration up to the desired level. We then determined the acute effect of glucose on the pressor and cardioaccelerator responses during static contraction of the hindlimb. The exercise pressor reflex was evoked in healthy, unanesthetized, decerebrated Sprague‐Dawley rats by statically contracting the hindlimb muscle for 30 seconds before and after 15 minutes of either glucose (250 mg/ml) or saline infusion, while mean arterial pressure and heart rate were recorded. We found that infusing 250 mg/ml of glucose significantly raised blood glucose levels to 486 ± 84 mg/dl by the 3rd minute compare to the control leg. However, infusing 125 mg/ml of glucose did not raise blood glucose concentration to 546 ± 33 mg/dl until the 11th minute compare to the control leg (p<0.05). Therefore, we decided to use 250 mg/ml glucose for the exercise pressor experiment. We then found that acutely infusing 250 mg/ml of glucose into the arterial supply of the hindlimb did not significantly affect the pressor (ΔMAP before glucose: 13 ± 0.4 mmHg; after glucose: 12 ± 0.8 mmHg, n=4; before saline: 11 ± 2 mmHg; after saline: 10 ± 2 mmHg, n=3; p>0.05) or cardioaccelerator (ΔHR before glucose: 14 ± 1 bpm; after glucose: 12 ± 2 bpm, n=4; before saline: 14 ± 3 bpm; after saline: 12 ± 4 bpm, n=3; p>0.05) responses to static contraction. We conclude that the acute presence of glucose in the circulation of the hindlimb muscles plays no role in exaggerating the exercise pressor reflex.

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
EXCESSIVE DIETARY SALT PROMOTES AORTIC STIFFNESS IN 2K1C HYPERTENSION
Authors: DeLalio Leon , Katayama Pedro , Hahn Scott , Straub Adam , Wenner Megan , Farquhar William , Stocker Sean
Published: June 2021

Renal artery stenosis is the most common cause of secondary hypertension. The 2‐kidney‐1‐clip (2K1C) model of renal stenosis is associated with elevated arterial blood pressure (ABP), activation of the sympathetic nervous system, and blunted reno‐renal reflexes and natriuretic responses. Excess dietary salt intake has multiple actions on the cardiovascular system and exacerbates ABP in some models of hypertension. The present study tested the hypothesis that 2K1C mice exhibit salt sensitive hypertension and worsening cardiovascular responses to high salt feeding. Male C57Bl6 mice (8–12 weeks) were fed 0.1% NaCl or 4% NaCl diets and ABP was continuously monitored using telemetry. 2K1C hypertension was produced by placing a 0.5mm length of PTFE tubing around the right renal artery. Baseline 24‐h mean ABP was not different between 0.1% versus 4.0% NaCl fed mice (101±1 vs 99±1 mmHg, respectively; n=8/group). 2K1C significantly increased ABP in both groups; however, 24‐h mean ABP at 3 weeks post‐renal clipping was not different between mice fed 0.1% vs 4.0% NaCl (122±3 vs. 124±6 mmHg, respectively; n=8/group). In addition, renal artery stenosis significantly increased arterial pulse pressure (systolic‐diastolic) in 0.1% NaCl (Day 0: 35±1 vs Day 21: 42±1 mmHg, P<0.05) and 4.0% NaCl (Day 0: 36±1 vs Day 21: 49±3 mmHg, P<0.05). Interestingly, the magnitude of the increase in arterial pulse pressure was significantly greater in mice fed 4.0% vs 0.1% NaCl (Δ14±3 vs Δ7±2 mmHg, P<0.05). This suggests dietary salt intake promotes aortic stiffness in the 2K1C model. To test this, endothelial‐dependent vasodilatory responses were measured using myography in sham and 2K1C mice fed 0.1% and 4.0% NaCl diets for 3 weeks. 4.0% NaCl 2K1C mice exhibited significantly blunted aortic vasodilation responses versus 2K1C mice fed 0.1% NaCl or sham mice fed 0.1% or 4.0% NaCl. These effects were not observed in the mesenteric arteries of the same animal. In vivo, pulse wave velocity (PWV) measurements revealed a significantly higher PWV value in 2K1C mice fed 4.0% NaCl versus 2K1C fed 0.1% NaCl (3.97±0.19; n=7 vs. 3.18±0.19; n=8, P<0.01) or sham fed 0.1% or 4.0% NaCl (3.21±0.19; n=7 vs. 3.01±0.19; n=7). We conclude that high dietary salt does not exaggerate the chronic hypertension in 2K1C mice but produces a specific endothelial‐dependent aortic stiffness.

Support or Funding Information

RO1 HL128388

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Age‐associated Alterations of Microglia in the Rostral Ventrolateral Medulla of F344 rats
Authors: Balivada Sivasai , Artalejo Adriana , Ortiz Richard J , Kenney Michael J
Published: June 2021

The Rostral ventrolateral medulla (RVLM) is a part of the medullary reticular formation and plays a critical role in the regulation of several physiological responses, including cardiovascular and sympathetic neural function. Although aging alters the responsiveness of the cardiovascular and sympathetic nervous systems, the role of the RVLM in age‐related physiological dysregulation remains unclear. Aging is associated with alterations in immune system‐related genes in various brain areas and our recent microarray analysis of the RVLM in young and aged rats revealed an increase in immune system‐related gene expression in the aged RVLM. Activation of immune system‐related genes implies changes in neuro‐immune interactions, suggesting brain resident immune cells, such as microglia, might be altered in the RVLM of aged F344 rats. In the present line of inquiry, we hypothesized that aging alters microglia in the RVLM of F344 rats. To test this hypothesis, the RVLM of young, middle‐aged, and aged F344 rats were analyzed for differences in microglia at molecular and cellular levels. First, whole rat genome microarrays of RVLM RNA samples were examined using gene ontology and pathway analysis to assess microglial phenotype in the aged RVLM. Second, age‐associated changes in microglia‐related gene expression in the RVLM was evaluated using qPCR. The microarray analysis indicated that molecular pathways involved in the regulation of microglia/macrophage phenotype, such as CXCR4, Toll‐like receptor, and inflammatory cytokine‐related signaling pathways were altered in the RVLM of aged rats (p<0.05, FDR<0.3). In addition, the RVLM of aged rats showed upregulation of microglia‐related genes, such as CD68, Tlr2, Trem2, and Fcrl2 (p<0.05, FDR<0.1). Our present experiments are characterizing RVLM microglia using IBA1 and MHC class ii immunohistochemistry. These preliminary results suggest that the microglial phenotype is altered in the RVLM of aged rats, providing an important foundation for age‐associated changes in neuro‐immune interactions in the RVLM and its effect on physiological responses.

Support or Funding Information

NIH grant AG‐041948, Minority Institutions program grant 5G12MD007592‐24 from the National Institute on Minority Health and Health Disparities (NIMHD).

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.