bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of Heat Stress on Monocyte Chemoattractant Protein‐1 Expression by Satellite Cells after Rat Skeletal Muscle Injury
Authors: Sugiyama Megumi , Kawashima Masato , Miyakawa Motoi , Taniguchi Kaho , Arakawa Takamitsu
Published: June 2021

Heat stress could promote skeletal muscle regeneration via early recruitment and invasion of macrophages into the necrotic muscle fibers (e.g., Takeuchi et al., 2014; Hatade et al., 2014). Macrophages play important roles in myoblasts proliferation, differentiation and fusion by producing some cytokines and be involved in muscle regeneration (e.g., Tidball, 2005; Arnold et al., 2007). But in the regeneration process, the mechanisms for the macrophages recruitment via the heat stress is unclear. Monocyte Chemoattractant Protein‐1 (MCP‐1) is involved in the migration, and this chemokine is produced by the satellite cells (e.g., Chazaud et al., 2003). Spatial distributions and chronological changes of the MCP‐1, Pax7 (a specific marker of satellite cells) and CD68 (a pan‐macrophages marker) were examined by using the immunohistochemistry via heat stress after crush injury to the extensor digitorum longus muscle of rats. In the present study, 8‐week old male Wistar rats weighing 180–200g were used. According to the crush method described by Furuta (2001) and our earlier reports (Takeuchi et al., 2014; Hatade et al., 2014), animals were anesthetized by an isoflurane and exposed the muscle. Next, the middle part of the muscle belly was crushed for 30s using forceps, to which a weight (500g) was attached. After the muscle crush injury, animals were randomly divided into heat and non‐heat groups. In the heat group, packs filled with hot water (42 degrees C) were percutaneously applied to the muscle for 20 min soon after the injury and in the non‐heat group were not. At 6, 12 and 24 h (n = 1, respectively) after the injury, animals were sacrificed, muscles were harvested and frozen cross sections (10 μm) of the injured muscle were prepared by cutting with a cryostat. Some sections were used for hematoxylin and eosin staining, the others were used for immunohistochemistry. At 6 h after the injury, macrophages were recruited around the degenerating muscle fibers in the non‐heat group. In the heat group, recruitment of the macrophages was higher than the non‐heat group. Similarly, recruitment and infiltration of macrophages in the heat group were higher than those in the non‐heat group at 12 h and 24 h after the injury. In addition, at 6 h after the injury of the heat group, the MCP‐1 was expressed in the satellite cells, whereas in the non‐heat group it was seen after 12 h, suggesting that the heat stress soon after the skeletal muscle injury might promote more rapid MCP‐1 expression of the satellite cells.

Support or Funding Information

None

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Fidelity of Reinnervation Modulates Susceptibility to Aging Muscle Impact and Frailty in Elderly Women
Authors: Sonjak Vita , Jacob Kathryn , Morais Jose , Spendiff Sally , Spake Carole , Rivera‐Zengotita Marie , Taivassalo Tanja , Chevalier Stéphanie , Hepple Russell
Published: June 2021

Background

Studies in aging rodent models and elderly men have recognized skeletal muscle denervation as an important factor contributing to age‐related muscle atrophy. This has not yet been assessed in octogenarian women, a population that is at a greater risk of becoming physically frail. On this basis we determined the presence of muscle denervation in prefrail/frail elderly women and its contribution to aging muscle phenotypes compared to a population with high function in advanced age, world class octogenarian track and field athletes.

Methods

Muscle biopsies were obtained from vastus lateralis muscle from prefrail/frail elderly women (FE, n=17, 77.9±1.5y), master athletes (MA, n=7, 80.9±2.2y) and young inactive (YI, n=12, 24.0±1.0y) controls, to assess denervation‐induced morphological and transcriptional markers.

Results

The FE group displayed a high abundance of grouped slow fibers, accumulation of very small myofibers, a severe reduction in type IIa to type I size ratio, and an accumulation of neural cell adhesion molecule‐positive myofibers and pyknotic nuclei, consistent with recurring cycles of denervation/reinnervation with a sporadic occurrence of failed reinnervation in prefrail/frail subjects. The MA group exhibited a smaller decline in type IIa/I size ratio, but not attenuated fiber atrophy relative to FE, and this was associated with a higher degree of fiber type I grouping in MA vs FE, suggesting a greater reinnervation of denervated fibers in MA. Consistent with this interpretation, MA had higher mRNA levels of the reinnervation promoting cytokine Fibroblast Growth Factor Binding Protein 1 than FE.

Conclusion

Our results indicate that the muscle of prefrail/frail elderly women undergoes significant neurogenic atrophy, whereas MA exhibit evidence of superior reinnervation capacity that attenuates functional decline with aging by attenuating aging muscle atrophy through better retention of muscle fiber number.

Support or Funding Information

This work was supported by Canadian Institute of Health Research (MOP 125986 and MOP 119583 to R.T. Hepple). Part of the expenses involving older participants was supported by an Internal Grant from the Helen McCall Hutchison Family Foundation of the Montreal General Hospital. V. Sonjak was supported by the Bloomberg Manulife Fellowship. K.J. Jacob was supported by a PhD scholarship from the Fonds de recherche du Quebec – Sante (FRQS).

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Neuromuscular Junction Plasticity Confers Atrophy Resilience of Aging Muscle
Authors: Burke Sarah Skinner , Fenton Andrew , Goddard Yana , Anagnostou Maria‐Eleni , Hepple Russell T
Published: June 2021

INTRODUCTION

Aging is associated with progressive muscle atrophy that contributes to weakness and increased risk of falls in advanced age. Our previous work has highlighted the importance of persistent denervation of muscle fibers (Rowan et al. PLoS One 2012), associated with a failed reinnervation response (Aare et al. Skeletal Muscle 2016), as a primary cause of muscle fiber atrophy in advanced age. We have also noted previously (Picard et al. Aging Cell 2011) that there is considerable heterogeneity between different muscles in severity of atrophy with aging that is unrelated to muscle fiber type composition per se. Most notably, in a comparison of two hindlimb muscles predominately composed of type I fibers in young adulthood, the soleus (Sol) exhibits a 30–40% decline in muscle mass while the adductor longus (AL) exhibits a remarkable 47% increase in muscle mass in advanced age rats. In view of the importance of denervation to aging muscle atrophy, we compared age‐related changes in neuromuscular junction (NMJ) morphology in the Sol and AL muscles to test the hypothesis that vulnerability to aging muscle atrophy parallels adaptive plasticity of the NMJ with aging.

FINDINGS

AL and Sol muscles were collected from 9‐mo old (YA) and 34‐mo old (VO) male Fischer 344 × Brown Norway F1‐hybrid (F344BN) rats (n=6; 3 YA) obtained from the colony maintained by the National Institute on Aging. NMJs in each muscle were immunofluorescently labelled and imaged by confocal microscopy (Leica SP8). Images were quantitatively assessed using NMJ‐Morph, an Image‐J based package designed for characterization and analysis of NMJ morphology. Interestingly, whereas for several parameters of NMJ morphology the AL exhibited changes with aging that were either not seen in the Sol or of greater magnitude in the AL, the majority of these parameters were already altered in the YA Sol versus the YA AL in the same direction as occurred with aging in the AL. As such, this suggests that NMJ morphological plasticity may be initiated much earlier in the lifespan in the Sol and that exhaustion of this plasticity may account for the atrophy susceptibility of the Sol in advanced age. Further to this, our data suggest that a substantial reserve of NMJ plasticity in the AL is amongst the factors responsible for its resilience to aging muscle atrophy in advanced age.

CONCLUSION

Our results are consistent with the hypothesis that vulnerability to aging muscle atrophy parallels adaptive plasticity of the NMJ with aging.

Support or Funding Information

SSB is supported by a T32 from the National Institute of Child Health and Human Development Grant T32HD043730.

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Characterizing mu Opioid Receptor Splice Variants Using Gene Targeting Rat Models Generated by Easi‐CRISPR
Authors: Rossi Grace , Xu Jin , Le Rouzic Valerie P , Pasternak Gavril W , Yoshiki Miyasaka , Mashimo Tomoji , Saunders Thom , Gurumurthy Channabasavaiah B , Pan Ying‐Xian
Published: June 2021

Background

A single‐copy mu opioid receptor (OPRM1) gene generates a vast array of mu opioid receptor splice variants through extensive alternative splicing that is conserved from rodent to human. These variants can be divided into two sets: exon 11 (E11) and exon 1 (E1) associated variants. The functional differences between the E1 and E11 sets of variants have been demonstrated using gene targeted mouse models.

Rationale/Significance

While mouse models are valuable, rats have many advantages both in behavioral modeling and in vivo manipulation.

Hypothesis

E11‐ and E1‐associated splice variants play important and distinct roles In opioid pharmacology.

Results

We have generated two conditional Oprm1 knockout (KO) models, E11‐KO and E1‐KO, in Sprague Dawley rats using a novel Easi‐CRISPR approach. Cre‐mediated E11 and E1 deletions was confirmed through breeding a CAG‐Cre rat. Initial behavioral studies showed that in both E11 and E1 KO rats, buprenorphine analgesia was lost. Buprenorphine CPP was significantly reduced in E11 KO rats. Morphine analgesia was completely lost in the E1‐KO rat, but intact in the E11‐KO rat.

Discussion

Our results suggest that buprenorphine analgesia is dependent on both E11 and E1‐associated variants, a similar scenario seen in the E11‐KO and E1‐KO mouse models. E11‐associated variants also involved in buprenorphine reward in rat. These conditional Oprm1 KO rat models will provide valuable resources for the research community and would expand our ability explore mu opioid pharmacology with approaches and techniques not feasible in mice.

Support or Funding Information

Supported by grants from NIH (DA40858, DA06241, DA042888 and CA08748)

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Antidepressant Effects of Crocin‐1 from Saffron in Mice with Chronic Unpredictable Mild Stress‐Induced Depression
Authors: Wang Ping , Lin Susu , Chen Zhuoyi , Jiang Yu , Jiang Jinyan , Liu Ling
Published: June 2021

Aim

Depression is a severe disorder that has enormous consequences for the individual's quality of life, and it is among the most prevalent forms of mental illness. Saffron, a famous herb medicine and spice in the world, has been suggested as a potential efficacious and tolerable treatment for depression and anxiety, while there is no study about the effect of crocin‐1 on depression and a few studies about the mechanism of saffron. So the aim of this study was to investigate the effects of crocin‐1, one of the most important active compounds in saffron, on chronic unpredictable mild stress (CUMS) induced depression in mice.

Methods

The effects of crocin‐1 were examined using CUMS induced depression ICR mice and factors including depressant‐like behaviors, neurotransmitters, the expression of MKP‐1, CREB and BDNF.

Results

Our data showed that crocin‐1 significantly prevented reduction of body weight induced by CUMS. Oral administration of crocin‐1 (10, 20, and 40mg/kg) markedly improved depressant‐like behaviors, increasing the latency and reducing the immobility time in both the tail suspension test and forced swimming tests, compared with the CUMS mice. Enzyme‐linked immunosorbent (Elisa) assay were performed on serum and it showed that crocin‐1 treatment not only restored the decreased neurotransmitter concentrations of dopamine (DA) and serotonin (5‐HT), but also increased the level of mBDNF and decreased proBDNF. The results of reverse transcription‐polymerase chain reaction and Elisa assay showed that crocin‐1 decreased the level of MKP‐1 mRNA and MKP‐1 expression in hippocampus, moreover, it also increased the level of BDNF mRNA expression and CREB mRNA expression.

Conclusion

Taken together, our study confirmed that crocin‐1 might have an antidepressant‐like effect in the CUMS model of depression in mice, and suggest it might be mediated by regulation of neurotransmitters, activation MKP‐1/CREB/BDNF pathway and balanced the ratio of proBDNF and mBDNF.

Support or Funding Information

This work was supported by Natural Science Foundation of China (81703688), China Postdoctoral Science Foundation (2016M592016) and Key Project of Science and Technology Department of Zhejiang Province (2015C02032).

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Role of Cortical Catecholamines in the Paradoxical Action of Psychostimulants
Authors: Harris Sharonda , Green Sara
Published: June 2021

Attention deficit hyperactivity disorder (ADHD) affects young children and manifests symptoms such as hyperactivity, impulsivity and cognitive disabilities. The primary line of treatment for ADHD are the psychostimulant class of drugs including amphetamine (Adderall) and methylphenidate (Ritalin). Several theories have been postulated on the paradoxical calming effect of psychostimulants on ADHD patients, but even after decades of research, their exact mechanism of action is unknown. Clinical studies have shown reduced levels of dopamine (DA) receptor and DA transporters (DAT) in ADHD patients, presumably due to elevated caudate DA levels. Studies using the dopamine (DA) transporter (DAT) knockout mice, which have elevated striatal DA levels and are considered an animal model of ADHD, have suggested that the paradoxical calming effect of psychostimulants might be through the parallel actions of other monoamine neurotransmitters. On the other hand, newer non‐stimulant classes of drugs such as atomoxetine and Intuniv suggest that targeting the norepinephrine (NE) system might explain the paradoxical calming effect. Again, the molecular and cellular mechanisms of action for these drugs or neurotransmitters in ADHD therapy is unknown.

Previous work has shown that DA levels in the PFC have a reciprocal effect on striatal DA levels and locomotion. Our preliminary data suggest that PFC D2+ pyramidal neurons project to the striatum and midbrain dopamine neurons and that infusion of D2 agonists in the PFC inhibits locomotion. We hypothesize that PFC DA through the action of PFC D2+ pyramidal neurons regulates striatal DA release and locomotion. To test our hypothesis we use ex vivo neurotransmitter release from mouse PFC slices, microdialysis and locomotor measurements, in NET and DAT knockout mice. Our preliminary data suggest that NET and SERT blockers not only increase extracellular levels of NE and 5HT, but also DA. These data suggest a possible role for cortical catecholamines in regulating the paradoxical effects of psychostimulants. Our future studies will not only shed light on the mechanism of psychostimulant action in ADHD therapy, but will facilitate development of newer therapies based on mechanistic evidence.

Support or Funding Information

Brain Behavior Research Foundation 27765 to N. Urs

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Mechanism of Arsenic Trioxide Inhibition of Cell Growth and Induction of Apoptosis in Triple Negative MDA‐MB‐231 Breast Cancer Cell Line
Authors: Alzuwaidi Sarah , Khalil Rafaat
Published: June 2021

Arsenic Trioxide ATO exhibits antitumor activities and potent inducer of apoptosis in a variety of cancer types, the exact mechanism of antitumor activity is not clear and its effectiveness in solid cancer remain controversial. Tumor necrosis factor‐alpha (TNF‐alpha) has also been shown to both induce apoptosis and prevent cell proliferation. The present study was designed to further investigate the effect of different concentrations of ATO on the viability of triple negative breast cancer MDA‐MB‐231 cell line, and to investigate apoptosis activated proteins induced by the treatment of ATO, TNF‐alpha, and combination. MDA‐MB‐231 cells exposed to seven different concentrations of ATO from 0 to 12 μM, for 24 hours, cell viability was measured by Alamar blue assay. Results show that ATO treatment effectively caused cell growth inhibition, and induced apoptosis in MDA‐MB‐231 cancer cells in a concentration‐dependent manner. Human apoptosis array is used to evaluate expression of apoptosis‐regulated proteins. Treated cells were labeled as control, ATO (2μM), TNF‐alpha (40 ng/ml) or combinations of ATO and TNF alpha, the arrays were made with dots corresponding to 43 major proteins. The analysis of dot blot intensity indicate that all treatments presented the same 43 proteins with a difference in the intensity of P53, Bcl2, BID, Caspase 3, Caspase 8, Cytochrome C, SMAC, HSP60, HSP70, HTRA2, and surviving proteins. Current results show that arsenic trioxide is useful to treat Breast cancer and apoptosis induced by activation of key regulatory proteins.

Support or Funding Information

Department of Biology

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 diet‐derived polyphenol EGCG on neurotensin response upon HL‐60 promyelocytic leukemia cells acquisition of a macrophage‐like phenotype
Authors: Dao Tiziana , Annabi Borhane
Published: June 2021

Background

The activation of a neurotensin (NTS)/neurotensin receptor (NTSR) axis in T lymphocytes, macrophages, and dendritic cells suggests that NTS could modulate immune response and trigger prosurvival signaling in malignant human B lymphocytes. Such axis can therefore represent a potential therapeutic target in chronic B cell leukemia.

Methods

In this study, analysis of NTS and NTSR1‐3 expression in acute myeloid leukemia (AML) patients using Kaplan‐Meyer plots specifically highlighted NTS and NTSRs as poor clinical prognosis biomarkers. NTSRs gene and protein expression was also explored in undifferentiated and upon phorbol 12‐myristate 13‐acetate (PMA)‐mediated differentiation of HL‐60 suspension cells, an acute promyelocytic leukemia subset cell line model from AML, into CD11b+/CD14− adherent macrophages.

Results

We found that high NTS internalization correlated with increased matrix metalloproteinase‐9 expression, and basal macrophage cell migration. Whereas NTS dose‐dependently enhanced undifferentiated HL‐60 cells chemotaxis, it rather inhibited cell migration in differentiated macrophages through decreased Erk, MEK and Src signaling pathways. Epigallocatechin‐3‐gallate (EGCG), a diet‐derived polyphenol with anti‐inflammatory and chemopreventive properties, prevented PMA‐induced CD11b expression and NTS internalization.

Conclusions

Our study evidences specific regulation and role for NTS receptors in HL‐60 differentiated macrophages, which could in part account for their contribution to immune evasion or tumor‐associated inflammation, and be prevented by the anti‐cancer property of diet‐derived polyphenols.

Support or Funding Information

Funding: UQAM Foundation and Chaire in Cancer Prevention and Treatment

This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Pioglitazone treatment inhibits Toll‐like receptor expression in vitro and in vivo
Authors: Dasu Ravi Krishna Mohan , Park Samuel , Devaraj Sridevi , Jialal Ishwarlal
Published: June 2021

Toll‐like receptors (TLRs) are key innate immune sensors of endogenous damage signals and play an important role in inflammatory diseases like diabetes and atherosclerosis. Pioglitazone (PIO) is widely used to lower blood glucose by increasing insulin sensitivty and decreasing inflammation by activating peroxisome proliferator‐activated receptor gamma (PPAR‐γ) in Type 2 diabetes. Thus, in the present study, we examined the anti‐inflammatory effects of Pioglitazone on TLR2 and TLR4 expression in human monocytes exposed to Pam3CSK4 (Pam: TLR2 ligand) and purified Lipopolysaccharide (LPS: TLR4 ligand) using flow cytometry. Monocytes were isolated from healthy human volunteers (n=10) and pretreated with PIO (1µM) followed by Pam (170ng/ml) and LPS (160ng/ml) challenge. PIO significantly decreased Pam and LPS induced TLR2 (‐56%) and TLR4 (‐78%) expression compared to Pam/LPS (P<0.05). In addition, PIO decreased Pam and LPS induced NF‐κB activity (‐63%), IL‐1β (‐50%), MCP‐1 (‐83%), and IP‐10 (‐46%) compared to control. Furthermore, PIO treated db/db mice (n=6/group) showed decreased TLR2 (‐60%) and TLR4 (‐45%) expression compared to vehicle control mice (P<0.001). Data suggests that Pam and LPS induced TLR2 and TLR4 expression are inhibited by PIO in human monocytes and db/db mice. Thus, we define a novel pathway by which Pioglitazone could induce anti‐inflammatory effects.
Effects of weight bearing and thermal conditions on equine digital hemodynamics
Authors: Stokes Ashley Michelle , Keowen Michael L , Eades Susan C , Moore Rustin M
Published: June 2021

Laminitis, a common equine disease, can develop secondary to painful contralateral limb conditions (i.e. Kentucky Derby winner 'Barbaro'). It is hypothesized that blood flow alterations, laminar structural failure (from excessive weight), or a combination are responsible.

The goals were to examine the effects of weight‐bearing and thermal conditions on equine digital hemodynamics.

8 horses were instrumented with a Doppler ultrasonic probe around the palmar digital artery and catheters in the palmar artery and digital vein. We measured digital hemodynamics and administered 15 um isotopic microspheres into the palmar arterial circulation under these conditions:

Weight equally‐balanced

Weight off of instrumented leg (zero loading)

Weight on instrumented leg (full loading)

Normal hoof temperature (32 ° C)

Cold hoof temperature (10 ° C)

Warm hoof temperature (54 ° C)

There was a significant effect of weight and temperature on laminar microspheres (p < 0.0001). This data demonstrates full loading results in decreased laminar perfusion. Additionally, ice therapy decreases and warm therapy increases perfusion. Interestingly, blood flow at the fetlock level, palmar arterial and digital venous pressures did not change. This demonstrates weight‐bearing and thermal conditions change blood flow reaching the laminar tissues and change the state of arteriovenous anastomoses.

Funding by Morris Animal Foundation.
Peer Instruction Benefits High‐, Middle‐, And Low‐ Performing Students
Authors: Giuliodori Mauricio Javier
Published: June 2021

Peer instruction was used in our veterinary physiology course (N: 101) to test the hypothesis that peer instruction enhances the performance of high‐, middle‐, and low‐ performing students. Each class of 90 min. was divided into four to six short segments (~15 min) that were followed by a qualitative problem solving quiz. Students answered the quizzes individually and then in groups of 2 ‐ 4. Individual and group scores for every student were recorded. Students were stratified, based on the individual scores, into quartiles and classified as high‐ (HPS), upper middle‐ (UMPS), lower middle‐ (LMPS), and lower performing students (LPS). Paired T test (individual vs. group scores) and Hedge's method for effect size were used. Results are showed in Table below. In conclusion, peer instruction enhanced the performance for high‐, middle‐, and low‐ performing students, and its effects were greater when the student scores were low.

Effect of Peer Instruction on student performance in a Veterinary Physiology course.
Asthma, Peripheral Cytokines and the Adolescent Swimmer
Authors: Wilson Lori Doss , Schwindt Christina D , Frank Zaldivar P , Graf Scott , Cooper Dan M
Published: June 2021

It is well recognized that elite level swimmers have elevated rates of asthma and exercise‐induced bronchoconstriction (EIB) either due to chronic exposure to chlorinated compounds or intense endurance training. The purpose of this study was to determine whether the peripheral cytokine levels (PCL) would be altered by a very brief but high intensity laboratory‐based exercise bout, and to see if changes were correlated with pulmonary function (PF) in elite adolescent swimmers with and without asthma. Following medication washout, 13 asthmatic and 24 control swimmers conducted the 8‐min ATS clinical EIB challenge (intensity = 85% of max.) on cycle ergometer. Spirometry was measure before and post exercise (up to 20 min.). Blood was collected before and end exercise. PCL increased significantly following exercise for the entire group; TNFα (p=.0005), IFNγ (p<.0001), P selectin (p<.0001), and TGFβ1 (p=.0008). No exercise effect was observed for IL6 or IL10. TGFβ1 levels decreased in female controls (p=.03) but increased in all other groups. There was a main effect for gender with IL4, males had greater increases than females (p=.009). Neither baseline or exercise‐induced alterations in PCL correlated with any of the PF parameters, EIB or asthma diagnosis. This study was funded by USA Swimming and NIH T32AR047752, R01HL080947, P01 HD048721 and M01RR00827.
Adenoviral endothelial nitric oxide synthase (NOS) expression in the paraventricular nucleus (PVN) inhibits mean arterial blood pressure in renal wrap hypertension
Authors: Northcott Carrie A , Chen Alex F , Haywood Joseph R
Published: June 2021

PVN nitric oxide (NO) has been implicated in hypertension. Moreover, PVN neuronal NOS is reduced during the onset of renal wrap hypertension. Thus, we hypothesized that increasing PVN NO would reduce the increase in mean arterial pressure (MAP) observed in renal wrap hypertension. In male sprague dawley rats radiotelemetry transmitters were implanted for MAP and heart rate (HR) measures. Baseline MAP and HR were obtained for one week. Adenoviruses (Ad) encoding eNOS or lacZ (a marker gene/control) were then microinjected into the PVN [1 x 109 pfu; bilateral (200nl/site)]. After one week of MAP and HR baseline measures post PVN Ad injections, renal wrap/sham surgeries were performed. Neither Ad LacZ nor Ad eNOS alone had effects on MAP or HR. Renal wrap surgery significantly increased MAP in both Ad LacZ and Ad eNOS wrap animals compared to sham counterparts. Five days post surgery the Ad eNOS wrap animals had a significantly lower MAP compared to Ad LacZ wrap rats (Ad LacZ wrap: 137 + 4; Ad eNOS wrap: 124 + 9; Ad Lac Z sham: 104 + 3; Ad eNOS sham: 107 + 5; p<0.05), with maximal inhibition occurring 10 days post wrap (Wrap Ad Lac Z: 146 + 6 vs. Ad eNOS: 123 +12 mm Hg, p<0.05). In conclusion, these data demonstrate that an increase in eNOS in the PVN, potentially increasing PVN NO, results in a blunting of MAP in renal wrap hypertension further demonstrating the role of PVN NO in blood pressure regulation in hypertension.
Beneficial cardiac effects of enalapril in postmenopausal hypertensive rats
Authors: Zilberman Judith Miriam , Yañes Licy L , Tomat Analia , Romero Mariana , Sartori‐Vallinoti Julio , Elesgaray Rosana , costa Maria A , Reckelhoff Jane F , Arranz Cristina
Published: June 2021

Several studies suggest an interaction between renin‐angiotensin system and estrogen with nitric oxide (NO) system and oxidative stress. Objective: To evaluate the effects of the angiotensin‐converting enzyme inhibitor enalapril (E) on systolic blood pressure (SBP), oxidative stress, NO synthase (NOS) activity and estrogen receptors expression in the left ventricle (LV) of postmenopausal spontaneously hypertensive rats (OF‐SHR). aged 16 month received E 250 mg/L in drinking water or tap water (C) for 30 days. At the end of the treatment lipid peroxidation end products (TBARS), estrogen receptors expression, catalase (CAT), glutathion peroxidase (GPx) and NOS activity were measured in LV.

Results

Treatment with enalapril decreased SBP and lipid peroxidation but increased GPx and NOS activity in OF‐ SHR. Estrogen receptor β was upregulated by E treatment in LV of OF‐SHR.

* p<0.02 vs control, #p<0.01 vs control.

In conclusión, our study shows that enalapril administration caused a reduction in oxidative stress and increases in NOS activity and estrogen receptor βexpression in LV of OF‐SHR. These results suggest that changes observed in the LV after menopause may be Angiotensin II mediated.
Ovariectomized female Dahl salt‐sensitive rats exhibit features of the metabolic syndrome
Authors: Sartori‐Valinotti Julio Cesar , Yanes Licy L. , Zhang Huimin , Reckelhoff Jane F.
Published: June 2021

Menopause is associated with increased salt‐sensitivity of blood pressure (BP) and risk of metabolic syndrome (MS). Ovariectomized (Ovx) Dahl salt‐sensitive rats (DS) show increased BP and body weight (BW) compared to intact females (Int). Rosiglitazone (RO) reduces BP in humans and blunts the BP response to high salt (HS) in Ovx. In human breast cancer cells, RO trans‐activates estrogen receptor (ER) alpha. We determined whether Ovx exhibit MS (Cohort A) and tested the hypothesis that the ER antagonist, Fulvestrant (FV), prevents the BP‐lowering effects of RO (Cohort B).

Methods

BP (telemetry), BW, plasma insulin, leptin and cholesterol levels were measured in Int and Ovx. Rats received Fulvestrant (FV, 10mg/rat IM or vehicle) while on low salt diet, and then were challenged to HS+RO (100 mg/kg diet) for 2 weeks (Cohort B).

Results

Cohort A: Data are displayed in the table. Cohort B: The increase in BP (delta) with HS was significantly higher in Ovx given FV and RO together (6.6±0.6) than in Ovx given RO only (‐2.3±2.1 mmHg, p<0.05). Thus Ovx DS exhibit features of MS and the data suggest that the effect of RO on BP may be ER dependent (supported by NIH HL66072 and AHA 0725561B)

* p<0.05 vs. Int
Measurement of regional kidney perfusion in mice: comparison of a novel, non‐invasive technique against conventional laser‐Doppler flowmetry.
Authors: Boesen Erika I , Wang Bin , Pollock David M , Sullivan Jennifer C
Published: June 2021

Laser‐Doppler (LD) flowmetry is the most well accepted method to assess regional kidney perfusion. Limitations include invasiveness and a very discrete (~ 1 mm3) area of measurement. The aim of this study was to compare regional kidney blood flow responses to endothelin‐1 (ET‐1) in male C57BL/6 mice obtained with LD methodology to those obtained using ultrasound (US) imaging with enhanced contrast agent (Vevo MicroMarker, VisualSonics). Renal cortical (CBF) and outer medullary perfusion (MBF) responses to ET‐1 were determined in isoflurane anesthetized mice using acutely implanted LD probes (implanted 1 mm and 3 mm respectively via retroperitoneal exposure of the left kidney) or by US imaging in separate groups of mice. Regional blood flow was determined using US by multiplying contrast agent volume and velocity in a user defined region of interest. Mice received a single i.v. injection of saline or ET‐1 (0.6, 1 or 2 nmol/kg) and responses were calculated 20 min post‐injection as % change from baseline values. ET‐1 reduced both CBF and MBF as measured by LD and by US. The pattern of responses was similar between techniques, although the magnitude of responses was larger with US. Total renal blood flow was also measured by pulse‐wave Doppler. The % changes in renal blood flow in response to increasing doses of ET‐1 were proportional to changes in regional blood flow (‐1±4, ‐22±8, ‐60±6, respectively). These data indicate that US imaging with enhanced contrast agent represents a viable, non‐invasive alternative to LD for assessing regional kidney blood flow responses in mice.
Chronic nifedipine mimics plasma volume expansion (PVE) seen in pregnancy – support for the underfill theory
Authors: Sasser Jennifer M , Fekete Andrea , Baylis Chris
Published: June 2021

This study was designed to test the "underfill hypothesis" of pregnancy which proposes that an enlarged vascular compartment (due to systemic vasodilation and shunting of blood to the placenta) results in renal sodium and water retention and consequent PVE. We produced chronic vasodilation by 14 days administration of the calcium channel blocker, nifedipine (NIF, 10mg/kg/day, po. n=5) to female Sprague Dawley rats, compared to those on control diet (CON n=6). Mean arterial blood pressure (BP) was monitored by telemetry. NIF reduced BP throughout the treatment period by 8.5±1.9% at day 2, 7.1±0.5% at day 10 and 4.5±0.9% at day 13. In CON, BP was stable throughout. At day 14, PV was determined by the Evans‐blue method, and measurements were made of hematocrit (Hct), plasma osmolarity (Posm), sodium (PNa), and total protein (CA) concentrations. As shown in the Table (*p<0.05 vs. CON), NIF lowered Hct and increased PV. Posm, PNa, and CA all fell. These responses closely resemble the responses to normal pregnancy with hemodilution (falls in hct and CA) due to marked PVE. The fall in Posm and PNa are also characteristic of pregnancy. We suggest that the primary vasodilation produced by NIF drives continual renal Na retention, causing volume expansion and partial "refilling" of the vasculature, hence return of BP towards baseline values.
The determinants of hepcidin‐ferroportin interaction
Authors: Preza Gloria , Fernandes Augustine , Clark Richard J , Craik David J , Ganz Tomas , Nemeth Elizabeta
Published: June 2021

Dysregulated production of the iron‐regulatory hormone hepcidin or abnormal interaction with its receptor ferroportin causes a spectrum of iron disorders. We analyzed the critical features of hepcidin and Fpn necessary for their interaction. The thiol form of Cys326 was essential for hepcidin binding and substitution of this Cys with Ser or Thr resulted in a complete loss of hepcidin binding, as did the treatment of cells with non‐permeable sulfhydryl‐alkylating agents. The essential role of the C326 residue in hepcidin binding accounts for the early and severe iron overload in patients with C326S or Y substitution in Fpn. We also showed that the N‐terminus of hepcidin was essential for its binding to Fpn. Ala scanning of N‐terminus indicated that substitution of Phe4 dramatically decreased hepcidin binding to Fpn. Position 4 required a bulky hydrophobic residue as substitution with cyclohexylalanine had no effect on activity but substitution with charged residues Lys or Asp resulted in a complete loss of activity. D‐Phe substitution rendered hepcidin inactive indicating the stereospecific requirement for the position 4. Cys7 was also critical for activity and a peptide composed of 9 N‐terminal amino acids acted as a less potent analog of hepcidin. Understanding the molecular framework responsible for hepcidin‐Fpn interaction will facilitate the development of drug leads for a range of iron disorders.
Effects of Ganoderan on the dysbacteria in intestinal tract of mice
Authors: Yang Xue‐Song , Yang Li‐Min , Yang Jixin , Zhang Leiyi , Kang Yu‐Ming , Yang Jingyun
Published: June 2021

The probiotics and prebiotis as microecological modulator have dramatic effects on the microdysbiosis. We found the effects of Ganoderan (GD) in normal flora in intestinal tract of mice. The mice were divided into normal group, decontaminated (DC) group, GD treated group and Bacillus bifidus praeparatum (LZCL) treated group, in which the three groups were treated per os with Lincomycin to be the DC model. After six‐day treatment, the intestinal flora were detected. Lincomycin decreased the number of Bifidobacterium, Bacteroid and Lactobacillus in intestinal tract of mice. The voltatile fatty acid, acetic acid, propionic acid and butanoic acid in blindgut of mice were decreased, suggesting that the dysbacteria were induced in DC mice. After six‐day treatment, the enteric bacilli and enterococcus of GD treatment group and LZCL group were lower than that of DC group, the Bifidobacterium and Bacteroid of GD treatment Group, while LZCL group were higher than that of DC group. The acetic acid, propionic acid and butanoic acid in blindgut of GD treated group and LZCL group were increased. But the level of acetic acid, propionic acid and butanoic acid in blindgut of DC group were lower than that of normal group. The morphologic data showed that the pathological changes of intestinal mucosa restored to normal state after treatment. These results suggest that the GD is an important microecological modulator.
Role of TLR‐2 in the sex‐specific response to dietary non‐alcoholic steatohepatitis
Authors: Rivera Chantal A , Gaskin LaTausha
Published: June 2021

While it is well‐known that female rodents are uniquely sensitized to the development of alcoholic hepatitis, studies establishing gender differences in non‐alcoholic steatohepatitis (NASH) are scarce and the limited information available is contradictory. The present study compared NASH pathogenesis in male and female mice. We hypothesized that sex differences in steatohepatitis may involve differential TLR signaling. Accordingly, C57BL/6 and TLR‐2−/− mice were fed a control or methionine/choline‐deficient diet (MCDD) for 8 wks. Steatosis, necrosis and inflammation were scored in H&E‐stained liver sections. Real‐time PCR was used to examine mRNA expression of TLR‐4, TLR‐2, CD14, TGFβ, TNFα, CYP 2e1 and collagen α1. Zone 3 NASH was observed in MCDD‐fed male mice. In females, injury and lipid accumulation were markedly enhanced compared to males, encompassing the entire hepatic acinus. Increased injury in females was associated with significantly elevated mRNA expression of TLR‐4, cytokines and collagen α1. In contrast, mRNA levels for TLR‐2 were highest in males, suggesting a protective role for TLR‐2. Indeed, injury was exacerbated in TLR‐2−/− males fed MCDD, whereas mild attenuation of injury, TLR‐4 signaling and cytokine production were observed in female TLR‐2−/− mice. These findings demonstrate unique gender responses to dietary NASH, and underscore a role of TLR‐2 in NASH pathogenesis.
Up‐regulation of RGS2 Mediate IL‐1beta‐Induced Decrease in Muscle Contraction in Response to NPR‐C activation in Tenia Coli
Authors: Mahavadi Sunila , Khaleduzzaman Mohammed , Grider John R , Murthy Karnam S
Published: June 2021

The proinflammatory cytokine, interleukine‐1β (IL‐1β), plays an important role in inflammation‐induced changes in smooth muscle contraction. IL‐1β inhibits acetylcholine release and muscle contraction in response to Gq‐coupled m3 receptor activation. Our previous studies have shown that the single‐transmembrane natriuretic peptide receptor, NPR‐C is coupled to Gi to stimulation of phosphoinositide (PI) hydrolysis via Gβγ i and muscle contraction.

AIM

To characterize the effect of IL‐1β on contraction in response to NPR‐C activation.

METHODS

Rabbit tenia coli were cultured in DMEM‐10 in the presence or absence of IL‐1β for 48 h. Muscle cells isolated from these strips were used for measurement of NPR‐C binding, PLC‐β3 and RGS2 expression, and cANP‐induced PI hydrolysis and muscle contraction.

RESULTS

Pre‐incubation with IL‐1β had no effect on NPR‐C binding or PLC‐β3 expression, but significantly inhibited cANP‐induced PI hydrolysis and muscle contraction. IL‐1β caused a 3‐4 fold‐increase in RGS2, a GTPase‐activating protein that accelerates inactivation of Gαi‐GTP, implying that the decrease in PI hydrolysis and contraction were mediated by increased deactivation of Gαi and formation of Gαβ γtrimer.

CONCLUSION

Inhibition of cANP‐induced contraction by IL‐1β reflects inhibition of PI hydrolysis resulting from up‐regulation of RGS2 and rapid inactivation of Gαi and inhibition of Gβγ i‐mediated PI hydrolysis.
Carbonic anhydrase inhibitor, acetazolamide, can change metabolism and growth of bacteria
Authors: TAKI KENJI , Nagasawa Zenzo
Published: June 2021

The influence on the metabolism and proliferation potency of bacillus were examined by addition of carbonic anhydrase inhibitor, acetazoramide (AZ).

Methods

It was evaluated by the cloudy rate of bacterial culture solution whether bacillus growth can be influenced by carbonic anhydrase inhibitor, acetazolamide (AZ). The cloudy rate of the culture solution was measured by using automatic bacillus inspection device (Walk away 40S1; Siemens Healthcare Diagnostics Inc., Brookfield, Connecticut, USA), and whether metabolism of bacillus can be influenced by AZ.

Results and Discussion

1.) The metabolism of all bacilli was accelerated in the sugar utilization in response to dosage of AZ. However, the acceleration of metabolism for the amino acid and the enzyme was different between gram positive and negative bacteria. According to the decrease in intracellular pH due to decrease in the carbonic anhydrase activity, the synthesis of bacterial membrane could change, and these differences could be caused by carbonic anhydrase activity. 2.) Proliferation potency of the bacillus was inhibited by clinical dose of AZ in Enterococcus spp. The proliferation potency was found to be reduced in response to the dosage of AZ in gram‐negative rod bacteria.

Conclusion

It has been understood that metabolism and the proliferation potency can be changed in response to dosage of AZ in gram negative and positive bacteria.
AMP activated kinase α‐1 subunit knock‐out causes concentric hypertrophy and elevated ventricular function
Authors: Schutrumpf Robert J , Rubin Leona J , Hanft Laurin M , Rindt Hans , Rovetto Michael J , McDonald Kerry S , Fine Deborah M
Published: June 2021

This study examined the effects of AMP activated kinase (AMPK) α‐1 subunit inactivation (KO) on cardiac morphology and function. Mouse heart function was first assessed by ECG and echocardiography under anesthesia. Hearts were then removed, weighed, and attached to a modified Langendorff apparatus. KO mice had increased heart weight‐to‐body weight ratios (WT = 0.475 ± 0.006 vs KO = 0.615 ± 0.024, P<0.001). Histopathologic evaluation revealed increased myocyte diameter (P<0.05) but no change in glycogen or connective tissue content in KO mice. Northern and Western blot analysis revealed similar α‐ and β‐ myosin heavy chain content, skeletal actin isoforms, and SERCA2 content between groups. Regarding cardiac function, ECG traces were similar between groups but both fractional shortening (WT = 26.8 ± 1.1% vs KO = 33.1 ± 1.7%, P= 0.005) and ejection fraction (WT = 60.4 ± 1.7% vs KO = 69.4 ± 2.4 %, P= 0.006) were increased in KO mice. Consistent with these data, left ventricular (LV) power output was greater in KO mice (WT = 7.3 ± 2.4 vs KO = 9.5 ± 1.3 g*cm/sec, P = 0.035). Interestingly, LV power increased ~30% after epinephrine in WT hearts but was unchanged in KO hearts. In conclusion, mice lacking the AMPK α‐1 subunit exhibit hypertrophy due, in large part, to enlargement of the myocyte cross sectional area. Hypertrophy was associated with increased contractility and reduced responsiveness to β‐adrenergic stimulation.
Caspase 3‐dependent neural cell apoptosis and telomere‐dependent senescence are activated in the cortex and brainstem in dietary‐induced obesity rat
Authors: Kishi Takuya , Hirooka Yoshitaka , Konno satomi , Ito Koji , Araki Shuichiro , Sunagawa Kenji
Published: June 2021

Background

In metabolic syndrome (MetS), oxidative stress causes organ damages. Oxidative stress also activates caspase 3‐dependent neural apoptosis and neural senescence progressed by abnormal shortening telomere length. We hypothesized that caspase 3‐dependent apoptosis and telomere‐dependent senescence in brain are activated in MetS.

Methods and Results

Male Sprague‐Dawley rats were fed on a moderately high‐fat diet. After 13 weeks, rats were segregated into obesity‐prone (OP) and obesity‐resistant (OR) based on their body weight. OP had significantly higher insulin resistance and lower adiponectin than OR. In OP, the activity of caspase 3 and the expression of pro‐apoptotic Bax and Bad were significantly increased, and the expression of anti‐apoptotic Bcl‐2 was significantly decreased in the cortex compared with OR (caspase 3; 25±4%, Bax;18±4%, Bad;21±3%, Bcl‐2; ‐28±4%, n=5 for each, P<0.01) and brainstem. Neural cell senescence determined by β‐galactosidase staining was significantly increased, and telomere length measured by quantitative RTm‐PCR method was significantly reduced in OP compared with OR.

Conclusion

These results suggest that, in MetS, the caspase 3‐dependent neural apoptosis and telomere‐dependent senescence are activated in the cortex and brainstem. This central alteration might contribute to pathophysiology of autonomic dysregulation in MetS.
The heme oxygenase system potentiates insulin‐signalling and enhance glucose metabolism in Zucker Diabetic Fatty rats
Authors: Ndisang Joseph Fomusi , Jadhav Ashok
Published: June 2021

Aldosterone causes oxidative insults by stimulating NF‐¿B, activating‐protein (AP‐1), and c‐Jun‐N‐terminal‐kinase (JNK). In type‐2 diabetes (T2D), aldosterone‐ and hyperglycaemia‐induced oxidative events constitute a potent destructive force. We investigated the role of heme oxygenase (HO) on aldosterone/oxidative stress and insulin‐signaling in Zucker diabetic fatty rat (ZDF).

HO was induced with hemin or inhibited with chromium mesoporphyrin (CrMP). Hemin reduced fasting/postprandial hyperglycaemia, while CrMP exacerbated hyperglycaemia in ZDF. The anti‐diabetic effect was accompanied by enhanced HO activity, catalase, bilirubin, ferritin and total anti‐oxidant capacity, whereas reduced aldosterone, 8‐isoprostane, JNK, NF‐¿B, AP‐1 and AP‐2 were observed. Interestingly, hemin increased insulin levels alongside cAMP and cGMP, two secondary‐messengers that also regulate insulin release. Furthermore, agents that promote insulin‐signaling including adiponectin, AMPK, aldolase‐B and GLUT4, were robustly increased. Correspondingly, hemin reduced glucose/insulin tolerance, lowered insulin resistance (HOMA‐IR), and reversed the inability of insulin to enhance GLUT4.

The suppression of hyperglycaemia‐ and aldosterone‐induced oxidative stress alongside the potentiation of insulin‐sensitizing pathways may account anti‐diabetic effect.
Xanthine oxidase inhibitor allopurinol attenuates the development of diabetic cardiomyopathy
Authors: Pacher Pal , Rajesh Mohanraj , Mukhopadhyay Partha , Bátkai Sandor , Mukhopadhyay Bani , Patel Vivek , Haskó György , Szabo Csaba , Mabley Jon , Liaudet Lucas
Published: June 2021

In this study we investigated the effect of the xanthine oxidase inhibitor allopurinol on cardiac dysfunction, oxidative‐nitrosative stress, apoptosis, poly(ADP‐ribose) polymerase (PARP) activity, and fibrosis associated with diabetic cardiomyopathy in mice. Diabetes was characterized by increased myocardial, liver and serum XO activity, increased myocardial ROS generation, p22phox, p40phox, p47phox, p91phox mRNA expression, iNOS expression, NT generation, caspase 3/7 and PARP activity/expression, chromatin fragmentation and fibrosis, and declined systolic and diastolic myocardial performance. Allopurinol attenuated the diabetes‐induced increased myocardial, liver and serum XO activities, myocardial ROS, NT generation, iNOS expression, apoptosis, PARP activity and fibrosis, which were accompanied by improved systolic and diastolic performance of the hearts of treated diabetic animals. Thus, XO inhibition with allopurinol improves type I diabetes‐induced cardiac dysfunction by decreasing oxidative/nitrosative stress and fibrosis, which may have important clinical implications for the treatment and prevention of diabetic cardiomyopathy and vascular dysfunction.