bluuebunny/crossref_metadata_2025 huggingface dataset:
Time Course of Blueberry Ingestion on Measures of Arterial Stiffness and Blood Pressure
Authors: McAnulty Lisa , Pike Julieanne , Collier Scott R. , Thompson Kyle L. , McAnulty Steven R.
Published: June 2021

Introduction

An individual's risk of cardiovascular disease is affected by numerous factors, with hypertension among the most significant. Specifically, hypertension causes increased pressure within the blood vessels which can compromise the integrity of the vasculature. Blueberries possess compounds known as anthocyanins which exert anti‐hypertensive properties and may reduce blood pressure. The objective of the present study was to examine the effect of daily blueberry ingestion on blood pressure, augmentation index (AIx), and central pulse wave velocity (cPWV) over a three week period, as well as to assess acute effects, one hour and two hours post‐consumption.

Methods

Participants (n=22) were composed of men and women between the ages of 40 to 70 years who met pre‐determined inclusion criteria. Participants were randomized into group A (n=10) or B (n=12) and received 38 g/d of freeze‐dried blueberry powder or placebo, respectively. Participants had baseline values obtained and then consumed A or B every evening with dinner for three weeks. Blood pressure, AIx, and cPWV were measured at the end of each week. At the end of the third week, participants had the weekly measures taken and then ingested 38g of A or B and had acute measures taken at one hour and two hours post ingestion.

Results

Participants did not differ based on age, height, weight, body mass index, or percent body fat. Chronic blueberry ingestion resulted in significant treatment time interaction effects for systolic blood pressure (p=0.036). No chronic treatment time interactions were observed for diastolic blood pressure, AIx, or cPWV. With respect to one hour and two hours post‐consumption, significant treatment time interaction effects were found for systolic blood pressure (p=0.015). No acute treatment time interactions were found for diastolic blood pressure, AIx, or cPWV. Furthermore, no significant treatment time interactions were observed for energy, macronutrient, or micronutrient intake including nutrients known to affect blood pressure.

Conclusion

Of interest was the change in systolic blood pressure following both acute and chronic dosing. It was not supported to be mediated by a change in vessel distensibility since PWV was not altered. Therefore, the change in blood pressure was most likely due to a change in HR both following acute supplement ingestion and as a chronic effect over time. This finding is of interest due to the relatively short time course and requires further investigation.

Support or Funding Information

U.S. Highbush Blueberry Council

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Microvascular Endothelial Dysfunction is Evident in Adults with Stage 1 Hypertension as Defined by the 2017 ACC/AHA Guidelines
Authors: Shank Sean , Greaney Jody , Alexander Lacy
Published: June 2021

The American Heart Association and American Council of Cardiology recently updated the guidelines defining hypertension to systolic blood pressure (BP) values >130 mmHg or diastolic BP values >80 mmHg (i.e., Stage 1 hypertension; HTN1). Hypertensive adults classified via the 2003 JNC7 definition (systolic BP >140 mmHg or diastolic BP >90 mmHg) are now categorized as having Stage 2 hypertension (HTN2). Adults with HTN2 exhibit pronounced microvascular dysfunction, one of the first pathophysiological manifestations of the disease. However, the degree to which endothelial dysfunction is evident in the microcirculation of adults meeting the updated definition of hypertension (HTN1) remains equivocal. We tested the hypotheses that microvascular endothelial dysfunction would be present in HTN1 compared to normotensive adults (NTN; systolic BP <120 mmHg and diastolic BP <80 mmHg) but would be less severe compared to HTN2. Endothelium‐dependent dilation (EDD) was retrospectively analyzed in 21 NTN (5 M; 51±1 yrs; resting BP 107±1/68±1 mmHg), 15 HTN1 (6 M; 54±1 yrs; resting BP 126±1/82±1 mmHg), and 37 HTN2 (24 M; 54±2 yrs; resting BP 144±1/93±1 mmHg). Red blood cell flux (laser Doppler flowmetry) was measured during graded intradermal microdialysis perfusion of the endothelium‐dependent agonist acetylcholine (ACh; 10−10–10−1 M). EDD was assessed as flux (perfusion units; PU) and cutaneous vascular conductance (CVC; flux·mmHg−1). Systolic and diastolic BP were significantly different between all three groups (P<0.05 for all). EDD was blunted in both HTN1 and HTN2 relative to NTN when expressed as both flux (NTN: 74±2 vs. HTN1: 60±3 vs. HTN2: 59±2 PU; all P<0.01) and CVC (NTN: 0.86±0.03 vs. HTN1: 0.62±0.04 vs. HTN2: 0.58±0.02 flux·mmHg−1; all P <0.01); however, ACh‐induced dilation was not different between HTN1 and HTN2 (flux P=0.9; CVC P=0.5). These preliminary data suggest that cutaneous microvascular endothelial dysfunction is evident in HTN1 and is as severe relative to HTN2. Future studies are required in order to elucidate the mechanistic mediators of vascular regulation in HTN1.

Support or Funding Information

Funding: NHLBI 5R01HL093238‐08, NIA 5T32AG049676‐02

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Urine connectin/titin is increased in patients after heart surgery with cardiopulmonary bypass
Authors: Tanihata Jun , Nishioka Naritomo , Inoue Takahiro , Bando Ko , Minamisawa Susumu
Published: June 2021

Background and Objective

Cardiac surgery with cardiopulmonary bypass (CPB) may accidentally cause perioperative cardiac injury, which would increase in the risk of substantial post‐operative morbidity and mortality. Therefore, the accurate evaluation of cardiac injury is important for patient care after surgery. Although several biomarkers from patients' serum have been already clinically available to detect cardiac injury, a sensitive urine biomarker for cardiac injury has not yet been established. Recently, N‐terminal fragment of connectin/titin (N‐connectin), a giant sarcomeric protein, has been reported to detect muscle damages in patients with skeletal muscle dystrophy and healthy volunteer with endurance exercise. In the present study, we tested whether urine N‐connectin can be a novel biomarker to detect cardiac damage after cardiac surgery with CPB.

Methods and Results

We measured urinary levels of N‐connectin/creatinine (N‐connectin/Cr; pmol/mg/dl) in 13 patients (9 male, 4 female; 63±16 years old) who had undergone cardiac surgery with CPB have given informed consent to participate. The patients included 5 on‐pump coronary artery bypass graft surgery and 8 open‐heart surgery for various heart diseases. Urine N‐connectin/Cr before operation was 3.8 ± 2.8 pmol/mg/dL and it was significantly increased in all patients after surgery (42.8. ±16.4 pmol/mg/dL at the operation day). Serum creatine phosphokinase‐MB isozyme (CK‐MB) before operation was 7.6 ± 2.7 U/L and it was also significantly increased after surgery (48.0. ± 37.4 U/L at the operation day). Although serum CK‐MB was rapidly decreased to the pre‐operative level 3 days after operation, urine N‐connectin/Cr was still significantly high 3 days after operation (29.5 ±10.4 pmol/mg/dL). There was no difference in Urine N‐connectin/Cr between patients who underwent on‐pump coronary artery bypass graft surgery and open‐heart surgery. Urine N‐connectin/Cr at the operation day had no correlation with other parameters including serum CK‐MB, cardiopulmonary bypass time, duration of Intensive care stay, and post‐operative left ventricular ejection fraction.

Conclusion

Urinary N‐connectin/Cr was significantly increased after CPB and maintained high values at least 3 days after surgery. Urinary N‐connectin/Cr may be useful to detect the risk of substantial post‐operative cardiac damage.

Support or Funding Information

This work was supported by grants from The the Jikei University research found.

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Hypertension Induces an Exaggerated Immune Response by Increasing CD86 Expression on Antigen Presenting Cells
Authors: Zhao Tuantuan , Li Yu , Bernstein Kenneth E. , Shen Xiao(Gregory) Z.
Published: June 2021

Hypertension is a major cause of cardiovascular morbidity and mortality. Evidence indicates that inflammation is a key participant in the pathology of hypertension. However, how an elevation of blood pressure affects the immune response is still poorly understood. To study this, we immunized angiotensin II (Ang II) dependent hypertensive mice and normotensive mice with ovalbumin (OVA) and several different adjuvants. Elevated CD8+ and CD4+T cell responses specific to OVA were observed in hypertensive mice. To determine whether the exaggerated T cell responses in hypertension translate into increased tissue pathology, we studied two models of autoimmune disease. RIP‐mOVA is a transgenic mouse line that expresses membrane‐bound OVA in pancreatic islet β cells. Some of these mice were made hypertensive with either Ang II or L‐NAME. When OVA‐specific OT‐I T cells were infused into RIP‐mOVA mice, the hypertensive mice had significantly more OT‐I T cells infiltration into the pancreas, and they developed diabetes more rapidly, than normotensive RIP‐mOVA animals. Also, concanavalin A induced hepatitis was significantly worsened by hypertension as compared to the pathology observed in normotensive mice.

The immune response above is due to the interaction of antigen presenting cells (APCs) and T cells. To study which cells are responsible for the heightened immune reactivity in hypertension, we characterized both T cells and APCs. We find that more effective APC presentation of antigen, and not differences in intrinsic T cell signaling, is a major instigator of the increased T cell response. For instance, OT‐I T cells from hypertensive mice responded similarly to such cells from normotensive mice when presented with OVA epitopes by normotensive APCs. In contrast, hypertensive APCs outperformed normotensive APCs in stimulating OT‐I T cells. Adoptive transfer of dendritic cells showed that APCs from hypertensive mice are responsible for the enhanced T cell response. We found that the key difference in the immune system of hypertensive mice is blood pressure mediated up‐regulation of CD86 on APCs. This is mediated by increased plasma ATP levels. These studies are the first to document that high blood pressure itself induces biochemical and immune changes that intensify inflammation in hypertension. They indicate ATP and CD86 as loci to potentially control hypertension associated inflammation.

Support or Funding Information

National Natural Science Foundation of China 31270950 (to XZS) NIH grant R21 AI114965(to KEB) NIH grant PO1 HL129941 (to KEB)

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Assay of Insulin‐Stimulated Signaling by Flow Cytometry: Key Points of Regulation
Authors: Melendy Shawn , Hetrick Byron , McCurdy Carrie
Published: June 2021

Type 2 Diabetes is an increasingly prevalent disease worldwide that is partially caused by a progressive loss of insulin response in adipose tissue and skeletal muscle, two essential insulin target tissues. Multicolor flow cytometry is a powerful tool that can be used to measure multiple signaling events simultaneously in specific cell types within mixed populations. The objective of this study is to design a sensitive and high‐throughput assay to measure key points of regulation in the insulin signaling pathway for adipocytes and myocytes using flow cytometry. We have developed a multicolor flow cytometry panel to measure the insulin stimulated phosphorylation of Akt (S473) and the transport of the insulin responsive glucose transporter GLUT4 to the plasma membrane. This assay is compatible with cell identity markers, such as CD56, to specifically measure insulin response of muscle cells within mixed populations. C2C12 myoblasts were stained with primary conjugated antibodies for pAkt (S473) and an extracellular region of GLUT4, indicating that GLUT4 is present in the plasma membrane. Both C2C12 myoblasts and non‐human primate primary myoblasts responded to insulin with increased pAkt (S473) and plasma membrane GLUT4 with an EC50 of <10nM, similar to physiological response. Akt phosphorylation and GLUT4 translocation were blocked by the actin depolymerizing agent Cytochalasin D. Future work will expand the panel to measure phosphorylation of insulin receptor substrate (IRS1) and phosphoinosital 3‐kinase (PI3K) activity by determining phosphoinosital (3,4,5) phosphate (PIP3) production. The sensitivity of the assay will be demonstrated with inhibitors to specific signaling events such as inhibition of PI3K by Wortmannin, and inhibition of Akt activation by MK‐2206. We anticipate that this will provide a powerful method to dissect the insulin signaling cascade in mixed populations of cells or to understand the role of specific regulatory elements in difficult to transfect primary cells.

Support or Funding Information

Supported by an APS STRIDE Summer Fellowship (SM), the University of Oregon UROP Mini‐Grant (SM), and the National Institute of Diabetes Digestive and Kidney Diseases under Award R01 DK095926 (CEM).

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Db/db Obese Mice Exhibit Enhanced Phosphorylation of p38, ERK1/2 and AKT in the Kidney
Authors: Haque Mohammed Ziaul , Kumar Vinod , Bettahi Ilham , Palaniyandi Suresh S. , Young Monika S. , Mohammad Ramzi M. , Abou Samra Abdul B.
Published: June 2021

Altered metabolic states due to obesity and diabetes have a direct impact on renal structure and function. Obesity and diabetes leads to several key morphological, subcellular fibrotic remodeling, nephropathy and renal failure. However the clear signaling mechanism is not known. Leptin receptor deficiency is associated with obesity and hypercholesterolemia. We showed that acute cholesterol depletion increased cellular function and phosphorylation of p38, ERK and AKT kinases. Hence we hypothesized that obesity enhances phosphorylation of p38, ERK1/2 and AKT kinases in the kidney. To test our hypothesis we used kidneys from 25 weeks old four leptin receptor deficient db/db obese mice and their age matched four c57BL6 (wild type) mice. Transverse slices were made from similar position of all kidneys. Kidney slices were chopped into very small pieces and homogenized under the ice cold lysis buffer with protease and phospahtase inhibitors. The low spin pellets were discarded and the supernatants were collected. Kidney lysates were run through 7–12% poly acrylamide gel electrophoresis. Phosphorylations of p38, ERK1/2 and AKT were measured using western blot and cell signaling antibodies. The results were normalized to β‐actin as a control for protein loading using NIH image J software. Data of phospho proteins expressed in arbitrary units for p38 (14477 ±1703 vs. 22488±2773, p<0.03), ERK1/2 (12408 ±1965 vs. 21807±1467, p<0.01) and AKTThr308 (10173 ±462 vs. 18250±1198, p<0.01) were more in obese db/db mice compared to wild type mice. Total p38, ERK1/2 and AKT were not different between db/db and wild type mice. We conclude that obesity is associated with enhanced phosphorylation of p38, ERK and AKTThr308 which could be associated with altered renal structure and function.

Support or Funding Information

Hamad Medical Research Center #16304

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Augmented Skeletal Muscle Vasodilation to Intravascular ATP During Exercise and Systemic Hypoxia in Humans
Authors: Terwoord Janée D. , Racine Matthew L. , Hearon Christopher M. , Richards Jennifer C. , Luckasen Gary J. , Joyner Michael J. , Dinenno Frank A.
Published: June 2021

We have recently demonstrated that vasodilation to the endothelium‐dependent agonist acetylcholine is amplified in contracting compared with quiescent skeletal muscle, highlighting the importance of the vascular endothelium in integrating vasomotor signals to regulate vascular tone in humans. In the present study, we tested the hypothesis that sensitivity to the endothelium‐dependent vasodilator ATP is augmented during exercise and systemic hypoxia, whereas sensitivity to the nitric oxide donor and endothelium‐independent dilator sodium nitroprusside (SNP) is not affected by these physiological conditions. In 12 young adults (7 M, 5 F), we measured forearm blood flow (FBF; Doppler ultrasound) and calculated changes in vascular conductance (FVC: quotient of FBF and mean arterial pressure) in response to local, intra‐arterial infusion of ATP or SNP during 1) control resting conditions (CON), 2) dynamic handgrip exercise (EX, 20 contractions per minute at 10% of maximal voluntary contraction), or 3) systemic hypoxia (HYP, 80% O2 saturation). Three doses of each vasodilator were infused via a brachial artery catheter during each condition (ATP: 1.25, 2.50, and 5.00 μg·dl forearm volume−1·min−1; SNP: 0.25, 0.50, and 1.00 μg·dl forearm volume−1·min−1). The order of drugs and conditions was randomized. Within each trial, infusions began after 3 min of rest, steady‐state exercise, or hypoxia, and each dose was infused for 2 min while the exercise or hypoxic stimulus was sustained. Compared to control conditions, vasodilatory sensitivity to the high dose of ATP was enhanced by 53 ± 18% during mild handgrip exercise (Δ FVC, CON: 120 ± 16 vs. EX: 176 ± 28 ml·min−1·100 mmHg−1; P < 0.05), whereas vasodilatory sensitivity was not affected at lower doses of ATP (P = NS; Dose × Condition interaction P < 0.05). In contrast, exercise had no effect on vascular sensitivity to any dose of SNP (P = NS). Similarly, during systemic hypoxia, vasodilation to ATP was enhanced by 18 ± 10% at the medium dose (Δ FVC, CON: 100 ± 15 vs. HYP: 125 ± 24 ml·min−1·100 mmHg−1; P < 0.05) and 28 ± 11% at the high dose (Δ FVC, CON: 120 ± 16 vs. HYP: 158 ± 27 ml·min−1·100 mmHg−1; P < 0.05; Dose × Condition interaction P < 0.05), whereas vasodilation to SNP was not different from control conditions at any dose (P = NS). These findings provide evidence that muscle contractions and hypoxia augment ATP‐mediated, endothelium‐dependent vasodilation in human skeletal muscle. Moreover, given that intravascular ATP increases under these physiological conditions, the results indicate that small changes in plasma ATP may result in augmented vasodilation and contribute to blood flow and oxygen delivery in humans.

Support or Funding Information

HL119337

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Differences in Autonomic Recovery Following Maximal Resistance Exercise in Young and Older Adults
Authors: Schroeder Elizabeth C. , Rosenberg Alexander J. , Grigoriadis Georgios , Wee Sang Ouk , Fernhall Bo , Baynard Tracy
Published: June 2021

Aging is associated with negative changes in autonomic function and an increased risk of cardiovascular disease. The risk of a sudden cardiovascular event is elevated during and immediately following vigorous exercise, potentially due to increased sympathetic dominance. Because resistance exercise provides a large hypertensive stimulus and young adults show reduced cardiac vagal control during recovery, further exploration of the effects of an acute bout of resistance exercise on autonomic function and recovery in older adults is required.

Purpose

To evaluate the effects of high‐intensity lower body resistance exercise on autonomic modulation in young (YA) and older adults (OA).

Methods

Thirty‐five YA (17 female, 26±5 years, BMI: 23.8±3.2 kg/m2) and 25 OA (14 female, 60±6 years, BMI: 29.9±5.4 kg/m2) completed 3 sets of 10 repetitions of maximal isokinetic knee flexion/extension on a force dynamometer in a semi‐recumbent position. Throughout the protocol, participants were instrumented with a 3‐lead ECG and finger‐photoplethysmography for continuous heart rate and blood pressure recordings. Time and spectral components of heart rate (HRV) and blood pressure variability (BPV), non‐invasive indices of autonomic function, were analyzed using five‐minute segments at baseline and 5‐minutes post‐resistance exercise.

Results

At baseline, OA had higher systolic and mean blood pressure, as well as lower root mean square of successive differences (RMSSD), low‐frequency (LF) RRI, high‐frequency (HF) RRI, and baroreceptor sensitivity (BRS) (p<0.05). At 5‐minutes post‐exercise, LF/HF ratio and LF systolic blood pressure increased (p<0.05). RMSSD, HF RRI, and BRS, were greater at baseline for YA and all variables decreased at 5‐min, while older adults did not change over time (interactions, p<0.05).

Conclusions

These results suggest YA exhibited parasympathetic withdrawal 5‐minutes post‐exercise, whereas OA either did not exhibit parasympathetic withdrawal or had already recovered at 5 min post exercise, but this cannot be distinguished from our data. Both groups appear to have elevated sympathetic modulation at 5‐min, as indicated by RRI, LF/HF and LF BPV. Further investigation of the response during exercise is required. However, there are clear differences in autonomic recovery following maximal resistance exercise in OA.

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Human placental derived stem cells protection in stroke injury.
Authors: Cananzi Sergio Giuseppe , Barzegar Mansoureh , Wang Yuping , Minegar Alireza , Boyer Christen , Knowles Kurt , Alexander Jonathan Steven
Published: June 2021

Although stroke remains the 2nd leading cause of mortality with disastrous effects on long‐term disability in adults, there are few effective therapeutic approaches which can reduce post‐ischemic brain injury and neurological defects. Recently, stem cell‐based therapies for stroke have been shown to be neuroprotective and neurorestorative. Since stroke is a non‐progressive neurological disease, stem cell therapy would be an ideal approach to limit inflammation, suppress injurious immune mechanisms and stimulation of endogenous repair processes. In this study, we are using placental derived stem cells (hPDSC) as a treatment for brain damage following ischemia/reperfusion. The objective of this study was to determine the therapeutic potential of hPDSC in the treatment of post‐ischemic brain injury after a stroke event. Our central hypothesis is that hPDSC will decrease brain damage following cerebral ischemia/reperfusion by reducing immune system activation and infiltration, oxidative stress, and enhancing survival pathways. We measured infarct size and neurological scores on Sprague‐Dawley rats using a 2h middle cerebral artery occlusion (MCAO) model of stroke injury in adult rats. We found that intra‐arterial administration of hPDSC (1×10^6/0.3 ml) at the time of reperfusion significantly reduced infarct size from 49.8±18.7% (MCAO/HBSS) to 12.9±6.3% (MCAO/hPDSC), p=0.003 (comparing ipsilateral to contralateral hemispheres). Similarly, neurological scores were improved from 12.4±1.51 (MCAO/HBSS) to 18.8±2.48 (MCAO/hPDSC) p=0.0012(Garcia scale). Although the mechanistic basis of protection is still not completely clear, hPDSC improvements seem to reflect sparing of the cortex; less protection appears to be seen in the caudate. This cortical protection was also associated with improvements in tissue histopathology characterized by reduced necrosis and vacuolization with apparent preservation of oligodendrocytes. Our findings demonstrate that acute intra‐arterial administration of hPDSCs during reperfusion can significantly improves stroke outcomes at 24h. Future studies to evaluate timing, cell dosing and the cellular/molecular mechanisms underlying their beneficial actions may even further improve overall outcomes in this form of stem cell therapy. These studies will help fill a void in our understanding of the influence of hPDSC on cerebral blood vessels and how these factors may reduce brain damage following a stroke event.

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
EFFECTS OF AEROBIC EXERCISE ON ISOPROTERENOL‐INDUCED CARDIAC DAMAGED RATS ASSOCIATED WITH BRAIN FUNCTIONS
Authors: Toth Kata , Nyakas Csaba , van der Zee Eddy A. , Schoemaker Regien G.
Published: June 2021

Background

A bidirectional relationship was found between myocardial infarction (MI) and depression in patients, while comorbidity worsens prognosis. Alterations in neuroimmune processes are suspected to play a role in this interaction. Exercise has been shown to be beneficial for both conditions separately. Moreover, exercise has been indicated to have anti‐inflammatory effects. Aim of this study is to investigate whether isoproterenol‐induced cardiac damage is leading to neuroinflammation, behavioral and cognitive changes; and whether exercise can affect these parameters.

Methods

Female Wistar rats (11 months) were injected with either isoproterenol hydrochloride (ISO); a nonselective beta‐adrenoceptor agonist (70 mg/kg) or saline s.c. on two consecutive days, and allowed to recover for 2 weeks. Then groups were divided into sedentary and exercise subgroups, the latter undergoing 4 weeks of moderate intensity treadmill running. Cardiac function was assessed with echocardiography. Depressive‐like behavior was measured by open field (OF), while cognitive function was obtained from novel location (NL) and novel object (NO) recognition tests. Neuroinflammation was examined immunohistochemically by microglia activation, calculated as cell body to cell size ratio in IBA‐1 stained sections.

Results

Cardiac dysfunction after ISO injection was confirmed by lower ejection fraction (EF; 72±1% in ISO vs 76±1% in saline rats), with no significant effect of exercise. Exercise tended to decrease depressive‐like behavior in the OF (% time in center: sedentary 7.8±1.8%; runners 13.1±1.9%; p=0.065). No significant effect of ISO on cognitive performance could be observed. ISO significantly decreased microglia activity by increasing dendrite area at similar cell body area (cell body/cell size 6.0±0.4 vs 7.6±0.4%) in the hippocampus CA1 area. Exercise had no significant effect on cognition or microglia morphology.

Conclusions

Cardiac dysfunction after repeated ISO injection in female rats reduced hippocampal microglial activation by increasing dendrite area. This may indicate alternative activation, associated with tissue protective properties. However, these immune changes were not associated with differences in behavior. Continuous aerobic exercise may increase exploration of the center of the OF, suggesting reduced anxiety.

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Acute Exercise and Brain BACE1 Protein Content: a Time Course Study
Authors: Yang Alex J. , Hayward Grant C. , MacPherson Rebecca EK.
Published: June 2021

Obesity and type 2 diabetes are significant risk factors in the development of neurodegenerative disorders, such as Alzheimer's disease (AD). A variety of cellular mechanisms, such as altered insulin and stress‐signaling contribute to neurodegeneration, and have been linked to increases in beta‐site amyloid precursor protein cleaving enzyme 1 (BACE1). BACE1 is the rate limiting enzyme in the production of amyloid‐beta peptides which are implicated in the pathology of AD. Previous work suggests that a single, acute bout of exercise may have beneficial neuro‐protective effects in the prefrontal cortex of obese mice, independent of weight loss. The purpose of this study was to examine‐ how long the exercise induced alterations in the prefrontal cortex persist following a single exercise bout. Male C57BL/6 mice were fed either a low (LFD, 10% kcals from lard) or a high fat diet (HFD, 60% kcals from lard) for 7 weeks. HFD mice then underwent an acute bout of exercise (treadmill running: 15 m/min, 5% incline, 120 min) followed by a recovery period of 2, 8, or 24 hours. The HFD resulted in increased body mass (LFD 27.8±1.05 vs HFD 41.7±0.60 g; p<0.05) and glucose intolerance (AUC LFD 63.27±4.5 vs HFD 128.9±4.6; p<0.05). In the prefrontal cortex, BACE1 protein content was reduced 2‐ and 8‐hours post‐exercise compared to the sedentary HFD group, however BACE1 protein content 24‐hours post‐exercise was not different (p<0.05). Compared to the LFD, the HFD had higher prefrontal cortex phosphorylation of p38, JNK, and Akt (Ser473), with no changes in ERK phosphorylation, indicative of increased neuronal stress and aberrant insulin signaling. Post‐exercise p38 and JNK phosphorylation were no different from either the HFD or LFD groups, while ERK phosphorylation was significantly reduced by 24‐hours of recovery. These changes were accompanied by an increase in circulating BDNF (pg/ml) at 24‐hour recovery (p<0.01). Our results suggest that a single, acute bout of exercise may have beneficial neuro‐protective effects in obesity. We provide evidence that an acute bout of exercise can reduce markers of stress‐signaling pathways as well as BACE1 protein content in the prefrontal cortex. However, the reduction in BACE1 content is short lived and highlights the importance of daily exercise interventions for long‐term improvements in early AD‐associated pathology.

Support or Funding Information

Supported by Alzheimer Society of Brant, Haldimand, Norfolk, Hamilton, and Halton PI:REKM

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Leptin Stabilizes Breathing but does not affect CO2 Chemosensitivity in Newborn Rat Pups
Authors: Hostovsky Liran Tamir , Ivanovska Julijana , Belik Jaques , Montadon Gaspard , Gauda Estelle B.
Published: June 2021

Premature infants have periodic breathing (PB) and chronic intermittent hypoxia (CIH) that increases during the 2nd week of life. Leptin (LEP) is a hormone produced by adipocytes and increases central CO2 chemoreceptors sensitivity. LEP is also produced by the placenta, and in newborn infants LEP levels are highest at birth and then rapidly fall. We hypothesis that the fall in LEP after birth is associated with the increase frequency of PB and apnea leading to CIH during the 2nd week of life in premature infants.

Objective

To determine the effect of exogenous LEP on breathing stability and CO2 sensitivity during the first week of postnatal life, using whole body flow‐through plethysmograph in freely behaving newborn rats.

Methods

Sprague Dawley (SD) rat pups remained with the nursing dam until the time of the experiment. On postnatal day (PD) 7, rat pups were injected intraperitoneally with either vehicle (saline/n=5), LEP6 (6 μg/gr/n=4) and LEP9 (9 μg/gr/n=5). After injection the pup was returned to nursing dam and litter mates for 30 mins followed by 30 mins in the plethysmograph prior to recording. Respiratory tracings were captured using PowerLab 8 data acquisition system (ADInstruments) and analyzed using LabChart. Ventilatory parameters; frequency, VT and Ve were compared during 21% O2, 40% O2/0% CO2, 40%O2/5%CO2 and return to 40%O2/0%CO2, and the coefficient of variation (CV) for Ve was calculated for each condition in the 3 treatment groups (SAL, LEP6, LEP9).

Results

Similar to Stunden et al. in rat pups at PD 7–8 (Stunden et al,, Respir Physiol, 2001), frequency, VT and Ve did not significantly changed in response to hypercapnia (P=0.511), and LEP6 or LEP9 did not alter this response. However, LEP exposure did stabilize breathing with a reduction in the CV during 21%O2, 40%O2/0%CO2 and 40%O2/5%CO2 (Figure 1).

Conclusion

Our preliminary findings are consistent with that of Stunden et al, who reported no change in Ve in response to hypercapnia at PD 6–8 in SD rats. At this age, the hypothalamus is insensitive to the effect of leptin on feeding and metabolism (MacKay H et al., Mol Metab. 2014). Here we show that leptin does not induce nor augment CO2 chemosensitivity in newborn rats at PD7, but does at PD 18 (Gauda et al, unpublished data), and adults (Isono S et al., Anesthesiology, 2009). However our data does show that leptin stabilizes breathing during the first week of life in newborn rat pups. We speculate that unstable breathing that occurs in premature infants may be associated with the precipitous fall in leptin levels after birth.

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Mechanism of Absorption and Transportation of Ovotransferrin in the Intestine
Authors: Shirkhani Rebin (Mohammad) , Lee Eun Joo , Talukder Jamil
Published: June 2021

Background

Ovotransferrin (OTF) is an iron‐binding protein present in eggs. It belongs to the transferrin family and shows sequence‐homology with mammalian transferrin and lactoferrin. This protein has been demonstrated to possess bioactive characteristics such as delivering iron to cells and inhibiting bacterial multiplication. However, the absorption and transportation of OTF through the intestinal epithelial cells remained unknown.

Aims

The objectives of this study were to determine the absorption and transportation mechanism of OTF through rat intestinal epithelial cells (IEC‐6).

Methods

IEC‐6 monolayer cells were grown on 6‐well transwell membrane with DMEM, bovine fetal serum, β‐hydroxybutyric acid, antibiotics, and insulin in a humidified CO2 incubator at 37°C. 10‐day post‐confluent cells were used for absorption and transport studies. OTF was loaded on the apical part and DPBS was collected from the bottom at 30 min at room temperature. Trans‐epithelial transport of OTF was initially detected by SDS‐PAGE with a molecular weight of 78 kDa. In order to carry out the real‐time uptake and transcytosis of OTF, 1 mg OTF/ml of DPBS was loaded and DPBS was collected from the bottom at different time intervals. Finally, the amount of OTF transported through the IEC‐6 cells following internalization was quantified by ELISA.

Results and Conclusion

The OTF destined to the cell membrane and internalized was visualized by immunofluorescent and laser confocal microscopy. Microscopic images clearly showed the accumulation of OTF on the cell membrane provided the evidence of OTF‐receptors' presence on the plasma membrane. Also, OTF was detected within the cytoplasm of IEC‐6 cells, revealed that it was internalized by receptor‐mediated endocytosis. ELISA results demonstrated that OTF can be taken up by IEC‐6 cells as an intact protein from the apical surface and transported to the basolateral surface through trans‐epithelial exocytosis mechanism. The maximum internalization and exocytosis were observed at 90 min. These processes were time and concentration dependent, as the transferrin and lactoferrin do. Therefore, it is concluded that absorption and trans‐epithelial transportation of OTF accomplished by receptor‐mediated transcytosis in intestinal epithelial cells.
The Nedd8 Co‐E3 DCNL4 is regulated by dietary potassium in renal intercalated cells and promotes WNK kinase degradation via the KLHL3/CUL3 complex
Authors: Nkashama Lubika J. , Roy Ankita , Carrisoza‐Gaytan Rolando , Ray Evan C. , Marciszyn Allison , Kleyman Thomas R. , Satlin Lisa M. , Subramanya Arohan R.
Published: June 2021

WNK kinases regulate NaCl and K+ transport in the distal nephron. The abundance of these kinases is controlled by the KLHL3/CUL3 complex, a cullin‐RING E3 ligase (CRL) that ubiquitylates the WNKs, marking them for degradation. Little is known about the mechanisms that physiologically regulate KLHL3/CUL3 complex activity. Mammalian DCN‐like (DCNL) proteins are a family of five evolutionarily conserved “co‐E3s” that promote CRL activation via neddylation. Since DCNL proteins are required for CRL activation in vitro, we hypothesized that specific DCNLs might be localized to the distal nephron to downregulate WNK kinases via the KLHL3/CUL3 complex. A kidney RNAseq database (Lee JW JASN 2015) detected DCNL4 transcripts in microdissected distal nephron segments, particularly the connecting tubule and cortical collecting duct. In immunohistochemistry and immunofluorescence studies, DCNL4‐specific antibodies detected a strong cytoplasmic signal in distal nephron intercalated cells (ICs). Notably, the signal was absent in the distal convoluted tubule and loop of Henle, the classical sites of WNK pathway activity. Recently, we showed that the abundance of the “long” kinase active form of WNK1 (L‐WNK1) is increased in ICs during dietary potassium loading. Consistent with this finding, dietary potassium loading (5% K+ with mixed citrate chloride and carbonate x10d) increased the abundance of the L‐WNK1 effector kinase SPAK in ICs, and decreased the abundance of DCNL4 by 53% by immunoblotting. Conversely, 10d of dietary K+ restriction upregulated DCNL4 in ICs and reciprocally decreased the abundance of L‐WNK1. In 293 cells, dicer substrate RNA‐mediated knockdown of DCNL4 increased endogenous steady state L‐WNK1 abundance, while overexpression of DCNL4 in the presence of KLHL3 and CUL3 enhanced L‐WNK1 degradation. These data support a model in which DCNL4 functions as an IC‐specific brake that downregulates L‐WNK1 and SPAK activity during hypokalemia, a process that is released during dietary potassium loading to activate IC‐mediated K‐secretion, possibly via basolateral NKCC1 cotransporters and apical BK channels. Thus, these findings suggest a novel physiological role for a specific DCNL protein in the regulation of potassium homeostasis.

Support or Funding Information

NIH R01DK098145, R01DK038470, P30DK079307

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Copper supplementation in drinking water reverses dietary iron overload‐induced anemia and cardiac hypertrophy in mice
Authors: Wang Tao , Xiang Ping , Ha Jung‐Heun , Doguer Caglar , Wang Xiaoyu , Flores Shireen , Kang Y. James , Collins James F.
Published: June 2021

Our previous studies showed that high‐iron (0.88% carbonyl iron) diet feeding of mice and rats lead to impaired growth, severe anemia, tissue copper depletion and cardiac hypertrophy.1,2 Interestingly, these pathophysiological perturbations were prevented by addition of extra copper to the high Fe diet, indicating the role of copper deficiency in the pathogenesis. The current study was undertaken to test the hypothesis that dietary copper supplementation to Fe overload mice could restore systemic copper status, and reverse the anemia and cardiac hypertrophy. Weanling, male C57BL/6 mice were fed AIN‐93G‐based diets containing adequate (~8 ppm) Cu in combination with adequate (~80 ppm) or high (~8000 ppm) Fe for 4 weeks. Then, the mice were given 20 mg/L Cu (as Cu sulfate) in drinking water for another 3 weeks. Subsequently, the iron and copper‐related phenotype of the mice was assessed. High‐Fe diet fed mice showed a significant growth impairment and systemic Cu deficiency, accompanied by severe anemia, decreased serum ceruloplamine (Cp) activity and cardiac hypertrophy. Cu replenishment via drinking water corrected the deficits in hemoglobin (Hb), hematocrit (HCT) and serum Cp levels, restored tissue Cu status, and reversed cardiac hypertrophy. It was further found that high‐Fe feeding significantly impaired intestinal Cu absorption, and disturbed Cu tissue distribution. This study demonstrates that high Fe consumption blocks intestinal Cu absorption, leading to a systemic Cu deficiency which resulted in a severe anemia and cardiac hypertrophy in mice. Cu supplementation corrects these physiologic perturbations. These observations provided further evidence of physiologically‐relevant iron‐copper interactions in mammals.

Support or Funding Information

Supported by NIH grant 1R01 DK074867 (to J.F.C.).

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Induced Pluripotent Stem Cells (iPS)‐Derived Extracellular Vesicles Improves Immune Dysfunction and Attenuates Splenomegaly in Aged Mice
Authors: Ullah Mujib , Feng Rui , Sun Zhongjie
Published: June 2021

Background and Objective

Aging is associated with declined immune function and increased inflammatory responses. Secreted extracellular vesicles (EVs) are loaded with growth factors, cytokines, and miRNAs. The purpose of this study is to investigate the effect of intravenous delivery of iPS cell‐derived EVs on the aging‐associated immune dysfunction.

Methods and Results

The iPS cell‐derived EVs was confirmed by the expression of CD9, CD63 and CD83. The populations of T and B lymphocytes were decreased in aged mice, indicating that aging impairs the immune function. Intravenous delivery of EVs rescued the aging‐related decrease in immune cell populations. The size and weight of spleens were increased in aged mice, suggesting that aging causes spleen hypertrophy (splenomegaly). We found that the aging‐related splenomegaly was accompanied by increased cell death, necrosis, unbalanced ratio of immune cells, and augmented inflammation. Immunosenescence, cell arrest, apoptosis, fibrosis and iron accumulation was also found in the hypertrophied spleens of aged mice. Interestingly, EVs significantly attenuated aging‐associated splenomegaly, immunosenescence, cell arrest, apoptosis, and spleen remodeling. Aging enhanced inflammation as evidenced by increased immune cells and proinflammatory cytokines (IL‐1β, IL‐18, TNF‐α) in aged mice. iPS cell‐derived EVs markedly reduced inflammation, improved population of B and T cells, and increased anti‐inflammatory cytokines (IL‐4, IL‐6, IL‐10, IL‐13, TGF‐β) in aged mice. In comparison with EVs alone, EVs overexpressing klotho protein (an antiaging protein) more effectively enhanced the immune function and suppressed inflammation in aged mice.

Conclusions

These results showed for the first time that EVs alone or in combination with klotho overexpression suppressed aging‐associated inflammation and splenocyte apoptosis likely via modulating the immune function. EVs may be a promising interventional strategy for aging‐related immune dysfunction and splenomegaly.

Support or Funding Information

NIH R01 AG049780, HL118558, AND DK093403.

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
The Effect of SIRT1 Expression on Glucose Metabolism in Lean and Obese Mice
Authors: Marshall Kent L. , Bryner Randy W. , Pitzer Christopher , Drake Alexis , Myers Matthew , Mohamed Junaith , Alway Stephen E.
Published: June 2021

Background

Sirtuin‐1 (SIRT1) through its deacetylase activity, is involved in numerous cellular processes including metabolism, gene silencing, and cellular survival. Recently, SIRT1 has been shown to play an important role in glucose metabolism and glucose tolerance, in part through its effect on insulin secretion and peripheral insulin sensitivity. Less is known about the exact tissue location for SIRT1's primary role in regulating blood glucose. In addition, little is known about the role SIRT1 may play in regulating blood glucose following the induction of an obese phenotype. We hypothesized that global over‐expression of the SIRT1 gene, as compared to lack of expression in metabolically active tissue, would allow for efficacious and enhanced glucose tolerance following hyperglycemic insult in both lean and obese animals.

Methods

Thirty‐two 60–70‐week‐old male and female (C57 Bl‐6) mice were used in the study. Groups were as follows: wild type (WT; N=10), SIRT1 global over‐expressors (OE; N=11), SIRT1 skeletal muscle satellite cell knockout (SKO; N=5), and SIRT1 skeletal muscle cell knockout (MKO; N=6). All groups underwent a glucose tolerance test (GTT) by administering an intraperitoneal injection of glucose solution containing 1g/kg of glucose relative to bodyweight following an eight hour fast. The resulting blood glucose levels were measured using tail stick and a standard Bayer™ Contour® glucometer at baseline, and 15, 30, 60, 90, and 120 minutes post‐injection. Following a 10‐week high caloric feeding regimen, which resulted in significant weight gain, WT and OE mice were given a second GTT. Data were analyzed using a one‐way and two‐way ANOVA with STATVIEW with significance set at 0.05.

Results

All measurements were determined to be independent of gender and weight. Initial fasting glucose levels were similar across all groups. Peak blood glucose was significantly lower in SKO (148±22 mg/dL) versus WT (207±21 mg/dL), OE (230 ± 10 mg/dl) and MKO (202 ± 12 mg/dl). The area under the glucose tolerance curves (AUC) was also significantly lower in SKO (652) versus WT (868), OE (895), and MKO (833). There was a significant interaction pre‐to‐post obesity between WT vs OE for AUC (WT‐pre: 868, WT‐post: 1108; OE‐pre: 895, OE‐post: 807).

Conclusion

Skeletal muscle satellite cell knockout of SIRT1 appeared to result in a better handling of glucose following IPGTT. Following 10 weeks of increased calorie consumption, resulting in significant weight gain, the OE group actually appeared to handle glucose better than WT litter‐mates.

Support or Funding Information

This project has been funded through grants from WV‐INBRE (NIH grant P20 GM103434) to the Genomics Core Facility and the WV Program to Stimulate Competitive Research (PSCoR)

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Channel catfish GLUT4 mRNA expression in various tissues and muscle changes in response to changes in feeding frequency
Authors: Schmidtberger Abigail Marie , Dougherty Megan , Abernathy Oaklee , Nevarez Ericka , Kostner Danica , Spainhour Rebekah , Kobayashi Yass
Published: June 2021

Glucose transporter proteins (GLUT) facilitate the movement of glucose across cell membranes. Various GLUT proteins, including GLUT1, 2, and 4, are distributed in all tissues throughout the body. The activity and expression of GLUT4 is regulated by insulin, making it important in maintaining proper blood glucose levels in the body. Although the role of GLUT4 in metabolism has been well‐characterized in mammals, tissue distribution and relative changes in the mRNA expression of GLUT4 in channel catfish has not yet been examined. For this study, our objectives were to characterize GLUT4 in channel catfish by examining its expression in various tissues. Tissue distribution of GLUT4 mRNA was examined in the brain, heart, liver, muscle, spleen, kidney, small intestine, and large intestine by using quantitative RT‐PCR. The expression of GLUT4 mRNA was detectable in all of the tissues examined. However, its expression was highly detectable in the brain, muscle, spleen, kidney, and large intestine compared to the other tissues. Changes in muscle GLUT4 mRNA expression in response to changes in feeding frequency were also examined. Juvenile catfish were assigned to receive food once every 12, 24, or 48 hours for 28 days (n=4 tanks per treatment, 8 fish per tank). Expression of GLUT4 mRNA was measured from muscle samples after the completion of the study (n=2 fish per tank). Muscle GLUT4 mRNA was not affected by changes in feeding frequency (P>0.10). We are currently examining the effects of feeding frequency on GLUT4 mRNA expression in the brain of channel catfish.

Support or Funding Information

This project was supported by the Institutional Development Award (IDeA) from the National Institute of General Medical Sciences of the National Institutes of Health under grant number P20GM103418.

This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.