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Bernardes-Ribeiro M, Patrone LGA, Cristina-Silva C, Bícego KC, Gargaglioni LH. Exercise derived myokine irisin as mediator of cardiorespiratory, metabolic and thermal adjustments during central and peripheral chemoreflex activation. Sci Rep 2024; 14:12262. [PMID: 38806563 PMCID: PMC11133352 DOI: 10.1038/s41598-024-62650-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Accepted: 05/20/2024] [Indexed: 05/30/2024] Open
Abstract
Exercise elicits physiological adaptations, including hyperpnea. However, the mechanisms underlying exercise-induced hyperpnea remain unresolved. Skeletal muscle acts as a secretory organ, releasing irisin (IR) during exercise. Irisin can cross the blood-brain barrier, influencing muscle and tissue metabolism, as well as signaling in the central nervous system (CNS). We evaluated the effect of intracerebroventricular or intraperitoneal injection of IR in adult male rats on the cardiorespiratory and metabolic function during sleep-wake cycle under room air, hypercapnia and hypoxia. Central IR injection caused an inhibition on ventilation (VE) during wakefulness under normoxia, while peripheral IR reduced VE during sleep. Additionally, central IR exacerbates hypercapnic hyperventilation by increasing VE and reducing oxygen consumption. As to cardiovascular regulation, central IR caused an increase in heart rate (HR) across all conditions, while no change was observed following peripheral administration. Finally, central IR attenuated the hypoxia-induced regulated hypothermia and increase sleep episodes, while peripheral IR augmented CO2-induced hypothermia, during wakefulness. Overall, our results suggest that IR act mostly on CNS exerting an inhibitory effect on breathing under resting conditions, while stimulating the hypercapnic ventilatory response and increasing HR. Therefore, IR seems not to be responsible for the exercise-induced hyperpnea, but contributes to the increase in HR.
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Affiliation(s)
- Mariana Bernardes-Ribeiro
- Departamento de Morfologia e Fisiologia Animal, Faculdade de Ciências Agrárias e Veterinárias, Universidade Estadual Paulista Júlio de Mesquita Filho (UNESP/FCAV), Via de Acesso Paulo Donato Castellane s/n, Jaboticabal, SP, 14870-000, Brazil
| | - Luis Gustavo A Patrone
- Departamento de Morfologia e Fisiologia Animal, Faculdade de Ciências Agrárias e Veterinárias, Universidade Estadual Paulista Júlio de Mesquita Filho (UNESP/FCAV), Via de Acesso Paulo Donato Castellane s/n, Jaboticabal, SP, 14870-000, Brazil
| | - Caroline Cristina-Silva
- Departamento de Morfologia e Fisiologia Animal, Faculdade de Ciências Agrárias e Veterinárias, Universidade Estadual Paulista Júlio de Mesquita Filho (UNESP/FCAV), Via de Acesso Paulo Donato Castellane s/n, Jaboticabal, SP, 14870-000, Brazil
| | - Kênia C Bícego
- Departamento de Morfologia e Fisiologia Animal, Faculdade de Ciências Agrárias e Veterinárias, Universidade Estadual Paulista Júlio de Mesquita Filho (UNESP/FCAV), Via de Acesso Paulo Donato Castellane s/n, Jaboticabal, SP, 14870-000, Brazil
| | - Luciane H Gargaglioni
- Departamento de Morfologia e Fisiologia Animal, Faculdade de Ciências Agrárias e Veterinárias, Universidade Estadual Paulista Júlio de Mesquita Filho (UNESP/FCAV), Via de Acesso Paulo Donato Castellane s/n, Jaboticabal, SP, 14870-000, Brazil.
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2
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Yang T, Wang Z, Li J, Shan F, Huang QY. Cerebral Lactate Participates in Hypoxia-induced Anapyrexia Through its Receptor G Protein-coupled Receptor 81. Neuroscience 2024; 536:119-130. [PMID: 37979840 DOI: 10.1016/j.neuroscience.2023.11.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2023] [Revised: 10/25/2023] [Accepted: 11/14/2023] [Indexed: 11/20/2023]
Abstract
Hypoxia-induced anapyrexia is thought to be a regulated decrease in body core temperature (Tcore), but the underlying mechanism remains unclear. Recent evidence suggests that lactate, a glycolysis product, could modulate neuronal excitability through the G protein-coupled receptor 81 (GPR81). The present study aims to elucidate the role of central lactate and GPR81 in a rat model of hypoxia-induced anapyrexia. The findings revealed that hypoxia (11.1% O2, 2 h) led to an increase in lactate in cerebrospinal fluid (CSF) and a decrease in Tcore. Injection of dichloroacetate (DCA, 5 mg/kg, 1 μL), a lactate production inhibitor, to the third ventricle (3 V), alleviated the increase in CSF lactate and the decrease in Tcore under hypoxia. Immunofluorescence staining showed GPR81 was expressed in the preoptic area of hypothalamus (PO/AH), the physiological thermoregulation integration center. Under normoxia, injection of GPR81 agonist 3-chloro-5-hydroxybenzoic acid (CHBA, 0.05 mg/kg, 1 μL) to the 3 V, reduced Tcore significantly. In addition, hypoxia led to a dramatic increase in tail skin temperature and a decrease in interscapular brown adipose tissue skin temperature. The number of c-Fos+ cells in the PO/AH increased after exposure to 11.1% O2 for 2 h, but administration of DCA to the 3 V blunted this response. Injection of CHBA to the 3 V also increased the number of c-Fos+ cells in the PO/AH under normoxia. In light of these, our research has uncovered the pivotal role of central lactate-GPR81 signaling in anapyrexia, thereby providing novel insights into the mechanism of hypoxia-induced anapyrexia.
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Affiliation(s)
- Tian Yang
- Department of Frigid Zone Medicine, College of High Altitude Military Medicine, Army Medical University, Chongqing 400038, China; Key Laboratory of Extreme Environmental Medicine, Ministry of Education of China, Chongqing 400038, China; Key Laboratory of High Altitude Medicine, PLA, Chongqing 400038, China
| | - Zejun Wang
- Department of Frigid Zone Medicine, College of High Altitude Military Medicine, Army Medical University, Chongqing 400038, China; Key Laboratory of Extreme Environmental Medicine, Ministry of Education of China, Chongqing 400038, China; Key Laboratory of High Altitude Medicine, PLA, Chongqing 400038, China
| | - Junxia Li
- State Key Laboratory of Trauma, Burns and Combined Injury, Department of Traumatic Shock and Transfusion, Research Institute of Surgery, Daping Hospital, Army Medical University, Chongqing 400042, China
| | - Fabo Shan
- State Key Laboratory of Trauma, Burns and Combined Injury, Department of Army Occupational Disease, Research Institute of Surgery, Daping Hospital, Army Medical University, Chongqing 400042, China.
| | - Qing-Yuan Huang
- Department of Frigid Zone Medicine, College of High Altitude Military Medicine, Army Medical University, Chongqing 400038, China; Key Laboratory of Extreme Environmental Medicine, Ministry of Education of China, Chongqing 400038, China; Key Laboratory of High Altitude Medicine, PLA, Chongqing 400038, China.
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Kesić M, Baković P, Farkaš V, Bagarić R, Kolarić D, Štefulj J, Čičin-Šain L. Constitutive Serotonin Tone as a Modulator of Brown Adipose Tissue Thermogenesis: A Rat Study. Life (Basel) 2023; 13:1436. [PMID: 37511811 PMCID: PMC10381595 DOI: 10.3390/life13071436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 06/21/2023] [Accepted: 06/22/2023] [Indexed: 07/30/2023] Open
Abstract
Brown adipose tissue (BAT), an important regulator of thermogenic and metabolic processes, is considered a promising target to combat metabolic disorders. The neurotransmitter and hormone serotonin (5HT) is a major modulator of energy homeostasis, with its central and peripheral pools acting in opposing ways. To better understand how individual variations in 5HT homeostasis influence the thermogenic functionality of BAT, we used a rat model consisting of two sublines with constitutively increased (high-5HT) or decreased (low-5HT) whole-body 5HT tone, developed by selective breeding for platelet 5HT parameters. We have shown that animals with constitutively low 5HT activity maintained at a standard housing temperature (22 °C) have greater interscapular BAT (iBAT) mass and higher iBAT metabolic activity (as evidenced by measurements of iBAT temperature and glucose uptake), accompanied by increased iBAT mRNA expression of key thermogenic genes, compared to animals with high 5HT tone. In response to further thermogenic challenges-intermittent cold exposure or treatment with a β3-adrenergic agonist-5HT sublines show several functional and molecular differences linking constitutively low endogenous 5HT tone to higher BAT activity/capacity. Overall, the results support a role of 5-HT in the control of BAT thermogenesis They also suggest that individuals with lower 5HT activity may be more sensitive to β3-adrenergic drugs.
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Affiliation(s)
- Maja Kesić
- Department of Molecular Biology, Ruđer Bošković Institute, HR-10000 Zagreb, Croatia
| | - Petra Baković
- Department of Molecular Biology, Ruđer Bošković Institute, HR-10000 Zagreb, Croatia
| | - Vladimir Farkaš
- Department of Experimental Physics, Ruđer Bošković Institute, HR-10000 Zagreb, Croatia
| | - Robert Bagarić
- Department of Experimental Physics, Ruđer Bošković Institute, HR-10000 Zagreb, Croatia
| | - Darko Kolarić
- Centre for Informatics and Computing, Ruđer Bošković Institute, HR-10000 Zagreb, Croatia
| | - Jasminka Štefulj
- Department of Molecular Biology, Ruđer Bošković Institute, HR-10000 Zagreb, Croatia
| | - Lipa Čičin-Šain
- Department of Molecular Biology, Ruđer Bošković Institute, HR-10000 Zagreb, Croatia
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4
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Passaglia P, Silva HB, de Jesus AA, Filho MAM, Trajano IP, Batalhão ME, Navegantes LCC, Branco LGS, Cárnio EC. Angiotensin-(1-7) improves tail skin heat loss and increases the survival of rats with polymicrobial sepsis. Peptides 2023; 167:171042. [PMID: 37315714 DOI: 10.1016/j.peptides.2023.171042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2023] [Revised: 06/02/2023] [Accepted: 06/08/2023] [Indexed: 06/16/2023]
Abstract
Sepsis is a serious syndrome, characterized by the excessive release of inflammatory mediators and thermoregulatory changes, being fever the most common sign. However, despite the importance of Angiotensin (Ang)-(1-7) in controlling the inflammation, the role of the peptide in the febrile response and mortality in animals submitted to experimental model of sepsis is still not clear. In this way, we evaluate the effect of continuous infusion of Ang-(1-7) in inflammatory response, thermoregulation and in mortality of Wistar male rats submitted to colonic ligation puncture (CLP). Before CLP surgery, the infusion pumps (Ang-(1-7), 1.5mg/mL or saline) were inserted into the abdominal cavity and maintained for 24hours. CLP rats showed a febrile response starting from 3h after and persisted until the 24th hour of experiment. Continuous treatment with Ang-(1-7) attenuated the febrile response and reestablished the euthermia 11h after CLP, until the end of experiment, which coincided with an increased heat loss index (HLI). This effect was associated with a decrease in production of pro-inflammatory mediators in liver, white adipose tissue (WAT) and hypothalamus. Moreover, an increase in norepinephrine (NE) content in interscapular brown adipose tissue (iBAT) was observed in CLP animals, which was attenuated with treatment with Ang-(1-7), and decreased mortality in CLP animals treated with Ang-(1-7). Taken together, the present study demonstrates that continuous infusion treatment with Ang-(1-7) can promote a global anti-inflammatory effect, reestablishing the tail skin heat loss as a key thermo-effector function, resulting in an increased survival of animals submitted to experimental sepsis.
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Affiliation(s)
- Patrícia Passaglia
- Department of Oral and Basic Biology Ribeirão Preto, School of Dentistry of Ribeirão Preto - University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Hadder Batista Silva
- Department of General Nursing, School of Nursing of Ribeirão Preto - University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Aline Alves de Jesus
- Department of Physiology, Ribeirão Preto Medical School - University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Marco Antonio Marangão Filho
- Department of General Nursing, School of Nursing of Ribeirão Preto - University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Isis Paiva Trajano
- Department of Physiology, Ribeirão Preto Medical School - University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Marcelo Eduardo Batalhão
- Department of General Nursing, School of Nursing of Ribeirão Preto - University of São Paulo, Ribeirão Preto, SP, Brazil
| | | | - Luiz Guilherme Siqueira Branco
- Department of Oral and Basic Biology Ribeirão Preto, School of Dentistry of Ribeirão Preto - University of São Paulo, Ribeirão Preto, SP, Brazil; Department of Physiology, Ribeirão Preto Medical School - University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Evelin Capellari Cárnio
- Department of Physiology, Ribeirão Preto Medical School - University of São Paulo, Ribeirão Preto, SP, Brazil; Department of General Nursing, School of Nursing of Ribeirão Preto - University of São Paulo, Ribeirão Preto, SP, Brazil
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5
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Andrade MT, Barbosa NHS, Souza-Junior RCS, Fonseca CG, Damasceno WC, Regina-Oliveira K, Drummond LR, Bittencourt MA, Kunstetter AC, Andrade PVR, Hudson ASR, Paula PH, Teixeira-Coelho F, Coimbra CC, Pires W, Wanner SP. Determinants of body core temperatures at fatigue in rats subjected to incremental-speed exercise: The prominent roles of ambient temperature, distance traveled, initial core temperature, and measurement site. INTERNATIONAL JOURNAL OF BIOMETEOROLOGY 2023; 67:761-775. [PMID: 36935415 DOI: 10.1007/s00484-023-02453-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 02/06/2023] [Accepted: 03/08/2023] [Indexed: 05/09/2023]
Abstract
Understanding the factors that underlie the physical exercise-induced increase in body core temperature (TCORE) is essential to developing strategies to counteract hyperthermic fatigue and reduce the risk of exertional heatstroke. This study analyzed the contribution of six factors to TCORE attained at fatigue in Wistar rats (n = 218) subjected to incremental-speed treadmill running: ambient temperature (TAMB), distance traveled, initial TCORE, body mass, measurement site, and heat loss index (HLI). First, we ran hierarchical multiple linear regression analyses with data from different studies conducted in our laboratory (n = 353 recordings). We observed that TAMB, distance traveled, initial TCORE, and measurement site were the variables with predictive power. Next, regression analyses were conducted with data for each of the following TCORE indices: abdominal (TABD), brain cortex (TBRAIN), or colonic (TCOL) temperature. Our findings indicated that TAMB, distance traveled (i.e., an exercise performance-related variable), initial TCORE, and HLI predicted the three TCORE indices at fatigue. Most intriguingly, HLI was inversely related to TABD and TBRAIN but positively associated with TCOL. Lastly, we compared the temperature values at fatigue among these TCORE indices, and the following descendent order was noticed - TCOL, TABD, and TBRAIN - irrespective of TAMB where experiments were conducted. In conclusion, TCORE in rats exercised to fatigue depends primarily on environmental conditions, performance, pre-exercise TCORE, and measurement site. Moreover, the influence of cutaneous heat loss on TCOL is qualitatively different from the influence on TABD and TBRAIN, and the temperature values at fatigue are not homogenous within the body core.
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Affiliation(s)
- Marcelo T Andrade
- Exercise Physiology Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, MG, 31.270-901, Belo Horizonte, Brazil
| | - Nicolas H S Barbosa
- Exercise Physiology Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, MG, 31.270-901, Belo Horizonte, Brazil
| | - Roberto C S Souza-Junior
- Exercise Physiology Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, MG, 31.270-901, Belo Horizonte, Brazil
| | - Cletiana G Fonseca
- Exercise Physiology Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, MG, 31.270-901, Belo Horizonte, Brazil
| | - William C Damasceno
- Exercise Physiology Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, MG, 31.270-901, Belo Horizonte, Brazil
| | - Kássya Regina-Oliveira
- Exercise Physiology Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, MG, 31.270-901, Belo Horizonte, Brazil
| | - Lucas R Drummond
- Exercise Physiology Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, MG, 31.270-901, Belo Horizonte, Brazil
- Department of Physical Education, Universidade do Estado de Minas Gerais, Unidade Divinópolis, MG, Divinópolis, Brazil
| | - Myla A Bittencourt
- Exercise Physiology Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, MG, 31.270-901, Belo Horizonte, Brazil
| | - Ana C Kunstetter
- Exercise Physiology Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, MG, 31.270-901, Belo Horizonte, Brazil
| | - Pedro V R Andrade
- Exercise Physiology Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, MG, 31.270-901, Belo Horizonte, Brazil
| | - Alexandre S R Hudson
- Exercise Physiology Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, MG, 31.270-901, Belo Horizonte, Brazil
| | - Pedro H Paula
- Exercise Physiology Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, MG, 31.270-901, Belo Horizonte, Brazil
| | - Francisco Teixeira-Coelho
- Exercise Physiology Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, MG, 31.270-901, Belo Horizonte, Brazil
- Department of Sport Sciences, Institute of Health Sciences, Universidade Federal do Triângulo Mineiro, MG, Uberaba, Brazil
| | - Cândido C Coimbra
- Laboratory of Endocrinology and Metabolism, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Washington Pires
- Exercise Physiology Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, MG, 31.270-901, Belo Horizonte, Brazil
- Physical Activity Laboratory, School of Physical Education, Universidade Federal de Ouro Preto, Ouro Preto, MG, Brazil
| | - Samuel P Wanner
- Exercise Physiology Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, MG, 31.270-901, Belo Horizonte, Brazil.
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Xu J, Gao W, He T, Yao L, Wu H, Chen Z, Lai Y, Chen Y, Zhang J. The hyperthermic response to intra-preoptic area administration of agmatine in male rats. J Therm Biol 2023; 113:103529. [PMID: 37055134 DOI: 10.1016/j.jtherbio.2023.103529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Revised: 01/31/2023] [Accepted: 02/22/2023] [Indexed: 03/05/2023]
Abstract
Agmatine is an endogenous biogenic amine that exerts various effects on the central nervous system. The hypothalamic preoptic area (POA, thermoregulatory command center) has high agmatine immunoreactivity. In this study, in conscious and anesthetized male rats, agmatine microinjection into the POA induced hyperthermic responses associated with increased heat production and locomotor activity. Intra-POA administration of agmatine increased the locomotor activity, the brown adipose tissue temperature and rectum temperature, and induced shivering as demonstrated by increased neck muscle electromyographic activity. However, intra-POA administration of agmatine almost had no impact on the tail temperature of anesthetized rats. Furthermore, there were regional differences in the response to agmatine in the POA. The most effective sites for the microinjection of agmatine to elicit hyperthermic responses were localized in the medial preoptic area (MPA). Agmatine microinjection into the median preoptic nucleus (MnPO) and lateral preoptic nucleus (LPO) had a minimal effect on the mean core temperature. Analysis of the in vitro discharge activity of POA neurons in brain slices when perfused with agmatine showed that agmatine inhibited most warm-sensitive but not temperature-insensitive neurons in the MPA. However, regardless of thermosensitivity, the majority of MnPO and LPO neurons were not responsive to agmatine. The results demonstrated that agmatine injection into the POA of male rats, especially the MPA, induced hyperthermic responses, which may be associated with increased BAT thermogenesis, shivering and locomotor activity by inhibiting warm-sensitive neurons.
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Santos ÁRC, Abreu ARR, Noronha SISR, Reis TO, Santos DM, Chianca-Jr DA, da Silva LG, de Menezes RCA, Velloso-Rodrigues C. Thermoregulatory responses, heart rate, and the susceptibility to anxiety in obese animals subjected to stress. Physiol Behav 2023; 266:114181. [PMID: 37019294 DOI: 10.1016/j.physbeh.2023.114181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 03/25/2023] [Accepted: 04/02/2023] [Indexed: 04/05/2023]
Abstract
Obesity and stress are related to cardiovascular diseases. Rats fed a high-fat diet (HFD) show increased cardiovascular reactivity to emotional stress and altered defensive behavioral responses. Indeed, changes in thermoregulatory responses in an aversive environment are observed in these animals. However, studies aimed at clarifying the physiological mechanisms linking obesity, stress hyperreactivity and behavioral changes are needed. The aim of this study was to evaluate the changes in thermoregulatory responses, heart rate, and the susceptibility to anxiety in obese animals subjected to stress. Nine-week high-fat diet protocol was effective in inducing obesity by increasing weight gain, fat mass, adiposity index, white epididymal, retroperitoneal, inguinal and brown adipose tissue. Animals induced to obesity and subjected to stress (HFDS group) by the intruder animal method showed increases in heart rate (HR), core body temperature and tail temperature. HFDS showed an increase in the first exposure to the closed arm (anxiety-like behavior) in elevated T-Maze (ETM). The groups did not differ with respect to panic behavior assessed in the ETM and locomotor activity in the open field test. Our study shows that HFDS animals presented increased reactivity to stress with higher stress hyperthermia and anxious behavior. Thus, our results present relevant information regarding stress responsiveness and behavioral changes in obese animals.
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Affiliation(s)
- Áquila Rodrigues Costa Santos
- Laboratory on Thymus Research, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil; Department of Basic Life Sciences, Federal University of Juiz de Fora, Governador Valadares, Brazil
| | - Aline Rezende R Abreu
- Laboratory of Cardiovascular Physiology, Department of Biological Sciences, Federal University of Ouro Preto, Ouro Preto, Brazil
| | - Sylvana I S R Noronha
- Laboratory of Cardiovascular Physiology, Department of Biological Sciences, Federal University of Ouro Preto, Ouro Preto, Brazil
| | - Thayane Oliveira Reis
- Laboratory of Cardiovascular Physiology, Department of Biological Sciences, Federal University of Ouro Preto, Ouro Preto, Brazil
| | - Daisy Motta Santos
- Department of Sports, School of Physical Education, Physiotherapy and Occupational Therapy, Federal University of Minas Gerais, Belo Horizonte, Brazil
| | - Deoclécio Alves Chianca-Jr
- Laboratory of Cardiovascular Physiology, Department of Biological Sciences, Federal University of Ouro Preto, Ouro Preto, Brazil
| | - Luiz Gonzaga da Silva
- Department of Basic Life Sciences, Federal University of Juiz de Fora, Governador Valadares, Brazil
| | - Rodrigo Cunha Alvim de Menezes
- Laboratory of Cardiovascular Physiology, Department of Biological Sciences, Federal University of Ouro Preto, Ouro Preto, Brazil
| | - Cibele Velloso-Rodrigues
- Department of Basic Life Sciences, Federal University of Juiz de Fora, Governador Valadares, Brazil.
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Cameron-Burr KT, Bola RA, Kiyatkin EA. Dantrolene sodium fails to reverse robust brain hyperthermia induced by MDMA and methamphetamine in rats. Psychopharmacology (Berl) 2023; 240:785-795. [PMID: 36700960 DOI: 10.1007/s00213-023-06321-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Accepted: 01/19/2023] [Indexed: 01/27/2023]
Abstract
RATIONALE Hyperthermia induced by psychomotor stimulants may cause leakage of the blood-brain barrier, vasogenic edema, and lethality in extreme cases. Current treatments such as whole-body cooling are only symptomatic and a clear need to develop pharmacological interventions exists. Dantrolene sodium, a peripheral muscle relaxant used in the treatment of malignant hyperthermia, has been proposed as potentially effective to treat MDMA-hyperthermia in emergency rooms. However, debate around its efficacy for this indication persists. OBJECTIVES To investigate dantrolene as a treatment for illicit hyperthermia induced by psychomotor stimulant drugs, we examined how Ryanodex®, a concentrated formulation of dantrolene sodium produced by Eagle Pharmaceuticals, influences 3,4-methylenedioxymethamphetamine (MDMA)- and methamphetamine (METH)-induced hyperthermia in awake freely moving rats. We injected rats with moderate doses of MDMA (9 mg/kg) and METH (9 mg/kg) and administered Ryanodex® intravenously (6 mg/kg) after the development of robust hyperthermia (>2.5 °C) mimicking clinical acute intoxication. We conducted simultaneous temperature recordings in the brain, temporal muscle, and skin to determine the basic mechanisms underlying temperature responses. To assess the efficacy of dantrolene in attenuating severe hyperthermia, we administered MDMA to rats maintained in a warm ambient environment (29 °C), conditions which produce robust brain and body hyperthermia (>40 °C) and lethality. RESULTS Dantrolene failed to attenuate MDMA- and METH-induced hyperthermia, though locomotor activity was significantly reduced. All animals maintained at warm ambient temperatures that received dantrolene during severe drug-induced hyperthermia died within or soon after the recording session. CONCLUSIONS Our results suggest that dantrolene sodium formulations are not mechanistically suited to treat MDMA- and METH-induced hyperthermia.
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Affiliation(s)
- Keaton T Cameron-Burr
- Behavioral Neuroscience Branch, National Institute on Drug Abuse - Intramural Research Program, National Institutes of Health, DHHS, 251 Bayview Blvd, Baltimore, MD, 21224, USA
| | - R Aaron Bola
- Behavioral Neuroscience Branch, National Institute on Drug Abuse - Intramural Research Program, National Institutes of Health, DHHS, 251 Bayview Blvd, Baltimore, MD, 21224, USA
| | - Eugene A Kiyatkin
- Behavioral Neuroscience Branch, National Institute on Drug Abuse - Intramural Research Program, National Institutes of Health, DHHS, 251 Bayview Blvd, Baltimore, MD, 21224, USA.
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Namisnak LH, Khoshnevis S, Diller KR. Interdependency of Core Temperature and Glabrous Skin Blood Flow in Human Thermoregulation Function: A Pilot Study. J Biomech Eng 2023; 145:041010. [PMID: 36305625 PMCID: PMC9791667 DOI: 10.1115/1.4056110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 10/20/2022] [Indexed: 12/30/2022]
Abstract
Human thermoregulation is governed by a complex, nonlinear feedback control system. The system consists of thermoreceptors, a controller, and effector mechanisms for heat exchange that coordinate to maintain a central core temperature. A principal route for heat flow between the core and the environment is via convective circulation of blood to arteriovenous anastomoses located in glabrous skin of the hands and feet. This paper presents new human experimental data for thermoregulatory control behavior along with a coupled, detailed control system model specific to the interdependent actions of core temperature and glabrous skin blood flow (GSBF) under defined transient environmental thermal stress. The model was tuned by a nonlinear least-squared curve fitting algorithm to optimally fit the experimental data. Transient GSBF in the model is influenced by core temperature, nonglabrous skin temperature, and the application of selective thermal stimulation. The core temperature in the model is influenced by integrated heat transfer across the nonglabrous body surface and GSBF. Thus, there is a strong cross-coupling between GSBF and core temperature in thermoregulatory function. Both variables include a projection term in the model based on the average rates of their change. Six subjects each completed two thermal protocols to generate data to which the common model was fit. The model coefficients were unique to each of the twelve data sets but produced an excellent agreement between the model and experimental data for the individual trials. The strong match between the model and data confirms the mathematical structure of the control algorithm.
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Affiliation(s)
- Laura H. Namisnak
- Department of Biomedical Engineering, The University of Texas at Austin, 107 West Dean Keeton Street Stop C0800, Austin, TX 78712
| | - Sepideh Khoshnevis
- Department of Biomedical Engineering, The University of Texas at Austin, 107 West Dean Keeton Street Stop C0800, Austin, TX 78712
| | - Kenneth R. Diller
- Department of Biomedical Engineering, The University of Texas at Austin, 107 West Dean Keeton Street Stop C0800, Austin, TX 78712
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10
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Garami A, Steiner AA, Pakai E, Wanner SP, Almeida MC, Keringer P, Oliveira DL, Nakamura K, Morrison SF, Romanovsky AA. The neural pathway of the hyperthermic response to antagonists of the transient receptor potential vanilloid-1 channel. Temperature (Austin) 2023; 10:136-154. [PMID: 37187834 PMCID: PMC10177699 DOI: 10.1080/23328940.2023.2171671] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2022] [Revised: 01/13/2023] [Accepted: 01/18/2023] [Indexed: 01/27/2023] Open
Abstract
We identified the neural pathway of the hyperthermic response to TRPV1 antagonists. We showed that hyperthermia induced by i.v. AMG0347, AMG 517, or AMG8163 did not occur in rats with abdominal sensory nerves desensitized by pretreatment with a low i.p. dose of resiniferatoxin (RTX, TRPV1 agonist). However, neither bilateral vagotomy nor bilateral transection of the greater splanchnic nerve attenuated AMG0347-induced hyperthermia. Yet, this hyperthermia was attenuated by bilateral high cervical transection of the spinal dorsolateral funiculus (DLF). To explain the extra-splanchnic, spinal mediation of TRPV1 antagonist-induced hyperthermia, we proposed that abdominal signals that drive this hyperthermia originate in skeletal muscles - not viscera. If so, in order to prevent TRPV1 antagonist-induced hyperthermia, the desensitization caused by i.p. RTX should spread into the abdominal-wall muscles. Indeed, we found that the local hypoperfusion response to capsaicin (TRPV1 agonist) in the abdominal-wall muscles was absent in i.p. RTX-desensitized rats. We then showed that the most upstream (lateral parabrachial, LPB) and the most downstream (rostral raphe pallidus) nuclei of the intrabrain pathway that controls autonomic cold defenses are also required for the hyperthermic response to i.v. AMG0347. Injection of muscimol (inhibitor of neuronal activity) into the LPB or injection of glycine (inhibitory neurotransmitter) into the raphe blocked the hyperthermic response to i.v. AMG0347, whereas i.v. AMG0347 increased the number of c-Fos cells in the raphe. We conclude that the neural pathway of TRPV1 antagonist-induced hyperthermia involves TRPV1-expressing sensory nerves in trunk muscles, the DLF, and the same LPB-raphe pathway that controls autonomic cold defenses.
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Affiliation(s)
- Andras Garami
- Thermoregulation and Systemic Inflammation Laboratory (FeverLab), St. Joseph’s Hospital and Medical Center, Phoenix, AZ, USA
- Department of Thermophysiology, Institute for Translational Medicine, Medical School, University of Pecs, Pecs, Hungary
| | - Alexandre A. Steiner
- Thermoregulation and Systemic Inflammation Laboratory (FeverLab), St. Joseph’s Hospital and Medical Center, Phoenix, AZ, USA
- Departamento de Imunologia, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, São Paulo, Brazil
| | - Eszter Pakai
- Thermoregulation and Systemic Inflammation Laboratory (FeverLab), St. Joseph’s Hospital and Medical Center, Phoenix, AZ, USA
- Department of Thermophysiology, Institute for Translational Medicine, Medical School, University of Pecs, Pecs, Hungary
| | - Samuel P. Wanner
- Thermoregulation and Systemic Inflammation Laboratory (FeverLab), St. Joseph’s Hospital and Medical Center, Phoenix, AZ, USA
| | - M. Camila Almeida
- Thermoregulation and Systemic Inflammation Laboratory (FeverLab), St. Joseph’s Hospital and Medical Center, Phoenix, AZ, USA
| | - Patrik Keringer
- Department of Thermophysiology, Institute for Translational Medicine, Medical School, University of Pecs, Pecs, Hungary
| | - Daniela L. Oliveira
- Thermoregulation and Systemic Inflammation Laboratory (FeverLab), St. Joseph’s Hospital and Medical Center, Phoenix, AZ, USA
| | - Kazuhiro Nakamura
- Department of Integrative Physiology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Shaun F. Morrison
- Department of Neurological Surgery, Oregon Health and Science University, Portland, OR, USA
| | - Andrej A. Romanovsky
- Thermoregulation and Systemic Inflammation Laboratory (FeverLab), St. Joseph’s Hospital and Medical Center, Phoenix, AZ, USA
- School of Molecular Sciences, University of Arizona, Tempe, AZ, USA
- Zharko Pharma, Inc., Olympia, WA, USA
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11
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Flewwelling LD, Wearing OH, Garrett EJ, Scott GR. Thermoregulatory trade-offs underlie the effects of warming summer temperatures on deer mice. J Exp Biol 2023; 226:287070. [PMID: 36808489 DOI: 10.1242/jeb.244852] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Accepted: 02/13/2023] [Indexed: 02/22/2023]
Abstract
Climate warming could challenge the ability of endotherms to thermoregulate and maintain normal body temperature (Tb), but the effects of warming summer temperatures on activity and thermoregulatory physiology in many small mammals remain poorly understood. We examined this issue in deer mice (Peromyscus maniculatus), an active nocturnal species. Mice were exposed in the lab to simulated seasonal warming, in which an environmentally realistic diel cycle of ambient temperature (Ta) was gradually warmed from spring conditions to summer conditions (controls were maintained in spring conditions). Activity (voluntary wheel running) and Tb (implanted bio-loggers) were measured throughout, and indices of thermoregulatory physiology (thermoneutral zone, thermogenic capacity) were assessed after exposure. In control mice, activity was almost entirely restricted to the night-time, and Tb fluctuated ∼1.7°C between daytime lows and night-time highs. Activity, body mass and food consumption were reduced and water consumption was increased in later stages of summer warming. This was accompanied by strong Tb dysregulation that culminated in a complete reversal of the diel pattern of Tb variation, with Tb reaching extreme highs (∼40°C) during daytime heat but extreme lows (∼34°C) at cooler night-time temperatures. Summer warming was also associated with reduced ability to generate body heat, as reflected by decreased thermogenic capacity and decreased mass and uncoupling protein (UCP1) content of brown adipose tissue. Our findings suggest that thermoregulatory trade-offs associated with daytime heat exposure can affect Tb and activity at cooler night-time temperatures, impacting the ability of nocturnal mammals to perform behaviours important for fitness in the wild.
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Affiliation(s)
- Luke D Flewwelling
- Department of Biology, McMaster University, 1280 Main Street West, Hamilton, ON, Canada, L8S 4K1
| | - Oliver H Wearing
- Department of Biology, McMaster University, 1280 Main Street West, Hamilton, ON, Canada, L8S 4K1
| | - Emily J Garrett
- Department of Biology, McMaster University, 1280 Main Street West, Hamilton, ON, Canada, L8S 4K1
| | - Graham R Scott
- Department of Biology, McMaster University, 1280 Main Street West, Hamilton, ON, Canada, L8S 4K1
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12
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Tattersall GJ, Campbell KL. Thermoconforming rays of the star-nosed mole. J Exp Biol 2023; 226:286733. [PMID: 36688286 DOI: 10.1242/jeb.245127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Accepted: 01/13/2023] [Indexed: 01/24/2023]
Abstract
The star-nosed mole (Condylura cristata) is renowned for its densely innervated 22 appendage star-like rostrum ('star') specialized for tactile sensation. As a northerly distributed insectivorous mammal exploiting aquatic and terrestrial habitats, these vascularized nasal rays are regularly exposed to cold water and thermally conductive soil, leading us to ask whether the star surface temperature, a proxy for blood flow, conforms to the local ambient temperature to conserve body heat. Alternatively, given the exquisite sensory nature of the star, we posited that the uninsulated rays may be kept warm when foraging to maintain high mechanosensory function. To test these hypotheses, we remotely monitored surface temperatures in wild-caught star-nosed moles. Although the tail acted as a thermal window exhibiting clear vasoconstriction/vasodilation, the star varied passively in surface temperature, with little evidence for thermoregulatory vasomotion. This thermoconforming response may have evolved to minimize conductive heat loss to the water or wet soils when foraging.
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Affiliation(s)
- Glenn J Tattersall
- Department of Biological Sciences, Brock University, 1812 Sir Isaac Brock Way, St Catharines, ON, CanadaL2S 3A1
| | - Kevin L Campbell
- Department of Biological Sciences, University of Manitoba, Winnipeg, MB, Canada, R3T 2N2
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13
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Chen R, Wang X, Xu H, Zhao R, Hu Q. Comparative Study on Volatile Oils among Bupleuri radix Species and Habitats: Yields, Chemical Characterization and Antipyretic Activities. Chem Biodivers 2022; 19:e202200549. [PMID: 36382416 DOI: 10.1002/cbdv.202200549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Accepted: 11/14/2022] [Indexed: 11/18/2022]
Abstract
Volatile oils from several Bupleuri radix (BR) are reported as potential sources of drugs. To provide evidence for the application of BR, the volatile oils from 19 batches of different species and habitats of BR including Bupleurum chinese DC. (BCD), Bupleurum scorzonerifolium Willd. (BSW), Bupleurum bicaule Helm (BBH), Bupleurum marginatum var. stenophyllum (Wolff) Shan et Y.Li (BMS), Bupleurum marginatum Wall.ex DC. (BMW) and Bupleurum falcatum L. (BFL) were investigated. The composition of BR volatile oils was determined by GC/MS. Samples were clustered by hierarchical cluster analysis (HCA). Fever was induced by Lipopolysaccharide (LPS), and antipyretic activities of BR volatile oils were evaluated with Chaihu injection (CI) as the positive control. The yields of volatile oils were among 360-5320 ppm. A total of 229 components were identified by GC/MS. Samples could be divided into 4 clusters by HCA. 4 representative samples, one for each cluster, were selected to further compare their antipyretic activities. For the highest content of volatile oil (5320 ppm) and the best activity, BSW has great potential for utilization.
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Affiliation(s)
- Ruoqiao Chen
- School of Pharmacy, Guangdong Pharmaceutical University, Guangzhou, 510006, China
| | - Xiaoshuang Wang
- Guangdong Provincial Key Laboratory of Clinical Research on Traditional Chinese Medicine Syndrome, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, 510006, China
| | - Hongting Xu
- School of Pharmacy, Guangdong Pharmaceutical University, Guangzhou, 510006, China
| | - Ruizhi Zhao
- Guangdong Provincial Key Laboratory of Clinical Research on Traditional Chinese Medicine Syndrome, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, 510006, China
| | - Qiaohong Hu
- School of Pharmacy, Guangdong Pharmaceutical University, Guangzhou, 510006, China
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14
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Keller AC, Chun JH, Knaub L, Henckel M, Hull S, Scalzo R, Pott G, Walker L, Reusch J. Thermoneutrality induces vascular dysfunction and impaired metabolic function in male Wistar rats: a new model of vascular disease. J Hypertens 2022; 40:2133-2146. [PMID: 35881464 PMCID: PMC9553250 DOI: 10.1097/hjh.0000000000003153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 03/03/2022] [Accepted: 03/04/2022] [Indexed: 11/26/2022]
Abstract
OBJECTIVE Cardiovascular disease is of paramount importance, yet there are few relevant rat models to investigate its pathology and explore potential therapeutics. Housing at thermoneutral temperature (30 °C) is being employed to humanize metabolic derangements in rodents. We hypothesized that housing rats in thermoneutral conditions would potentiate a high-fat diet, resulting in diabetes and dysmetabolism, and deleteriously impact vascular function, in comparison to traditional room temperature housing (22 °C). METHODS Male Wistar rats were housed at either room temperature or thermoneutral temperatures for 16 weeks on either a low or high-fat diet. Glucose and insulin tolerance tests were conducted at the beginning and end of the study. At the study's conclusion, vasoreactivity and mitochondrial respiration of aorta and carotid were conducted. RESULTS We observed diminished vasodilation in vessels from thermoneutral rats ( P < 0.05), whereas high-fat diet had no effect. This effect was also observed in endothelium-denuded aorta in thermoneutral rats ( P < 0.05). Vasoconstriction was significantly elevated in aorta of thermoneutral rats ( P < 0.05). Diminished nitric oxide synthase activity and nitrotyrosine, and elevated glutathione activity were observed in aorta from rats housed under thermoneutral conditions, indicating a climate of lower nitric oxide and excess reactive oxygen species in aorta. Thermoneutral rat aorta also demonstrated less mitochondrial respiration with lipid substrates compared with the controls ( P < 0.05). CONCLUSION Our data support that thermoneutrality causes dysfunctional vasoreactivity, decreased lipid mitochondrial metabolism, and modified cellular signaling. These are critical observations as thermoneutrality is becoming prevalent for translational research models. This new model of vascular dysfunction may be useful for dissection of targetable aspects of cardiovascular disease and is a novel and necessary model of disease.
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Affiliation(s)
- Amy C. Keller
- Division of Endocrinology, Metabolism & Diabetes, University of Colorado Anschutz Medical Campus
- Rocky Mountain Regional VA Medical Center, Aurora, Colorado
| | | | - L.A. Knaub
- Division of Endocrinology, Metabolism & Diabetes, University of Colorado Anschutz Medical Campus
- Rocky Mountain Regional VA Medical Center, Aurora, Colorado
| | - M.M. Henckel
- Division of Endocrinology, Metabolism & Diabetes, University of Colorado Anschutz Medical Campus
- Rocky Mountain Regional VA Medical Center, Aurora, Colorado
| | - S.E. Hull
- Division of Endocrinology, Metabolism & Diabetes, University of Colorado Anschutz Medical Campus
- Rocky Mountain Regional VA Medical Center, Aurora, Colorado
| | - R.L. Scalzo
- Division of Endocrinology, Metabolism & Diabetes, University of Colorado Anschutz Medical Campus
- Rocky Mountain Regional VA Medical Center, Aurora, Colorado
| | - G.B. Pott
- Division of Endocrinology, Metabolism & Diabetes, University of Colorado Anschutz Medical Campus
- Rocky Mountain Regional VA Medical Center, Aurora, Colorado
| | - L.A. Walker
- Division of Cardiology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - J.E.B. Reusch
- Division of Endocrinology, Metabolism & Diabetes, University of Colorado Anschutz Medical Campus
- Rocky Mountain Regional VA Medical Center, Aurora, Colorado
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15
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Henderson M, Halsey L. The metabolic upper critical temperature of the human thermoneutral zone. J Therm Biol 2022; 110:103380. [DOI: 10.1016/j.jtherbio.2022.103380] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 05/11/2022] [Accepted: 10/21/2022] [Indexed: 11/11/2022]
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16
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Bigiarelli KJ. Rodent Thermoregulation: Considerations for Tail-Cuff Blood Pressure Measurements. JOURNAL OF THE AMERICAN ASSOCIATION FOR LABORATORY ANIMAL SCIENCE : JAALAS 2022; 61:406-411. [PMID: 35948400 PMCID: PMC9536829 DOI: 10.30802/aalas-jaalas-22-000006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Noninvasive blood pressure measurement devices have gained popularity in recent years as an alternative to radiotelemetry and other invasive blood pressure measurement techniques. While many factors must be considered when choosing a measurement method, specific variables should be evaluated when using a tail-cuff blood pressure technique. Rodents have complex and dynamic thermal biology processes that involve fluctuating vasomotor tone of the tail. This and other factors that affect vascular tone, such as the autonomic response to stress, significantly affect peripheral blood flow. Awareness and consideration of thermoregulatory states and vasomotor tone can increase success and decrease variability when measuring blood pressure measurements using a tail-cuff measurement technique.
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Affiliation(s)
- Krista J Bigiarelli
- Pre-Clinical Research and Development, Kent Scientific Corporation, Torrington, Connecticut,Corresponding author.
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17
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Andrade MT, Goulart KNO, Barbosa NHS, Soares DD, Andrade AGP, Gonçalves DAP, Mendes TT, Coimbra CC, Wanner SP. Core body temperatures of rats subjected to treadmill exercise to fatigue or exhaustion: The journal Temperature toolbox. Temperature (Austin) 2022; 10:287-312. [PMID: 37554383 PMCID: PMC10405761 DOI: 10.1080/23328940.2022.2115274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 08/12/2022] [Accepted: 08/16/2022] [Indexed: 10/14/2022] Open
Abstract
This study systematically reviewed the literature reporting the changes in rats' core body temperature (TCORE) induced by either incremental- or constant-speed running to fatigue or exhaustion. In addition, multiple linear regression analyses were used to determine the factors contributing to the TCORE values attained when exercise was interrupted. Four databases (EMBASE, PubMed, SPORTDiscus, and Web of Science) were searched in October 2021, and this search was updated in August 2022. Seventy-two studies (n = 1,538 rats) were included in the systematic review. These studies described heterogeneous experimental conditions; for example, the ambient temperature ranged from 5 to 40°C. The rats quit exercising with TCORE values varying more than 8°C among studies, with the lowest and highest values corresponding to 34.9°C and 43.4°C, respectively. Multiple linear regression analyses indicated that the ambient temperature (p < 0.001), initial TCORE (p < 0.001), distance traveled (p < 0.001; only incremental exercises), and running speed and duration (p < 0.001; only constant exercises) contributed significantly to explaining the variance in the TCORE at the end of the exercise. In conclusion, rats subjected to treadmill running exhibit heterogeneous TCORE when fatigued or exhausted. Moreover, it is not possible to determine a narrow range of TCORE associated with exercise cessation in hyperthermic rats. Ambient temperature, initial TCORE, and physical performance-related variables are the best predictors of TCORE at fatigue or exhaustion. From a broader perspective, this systematic review provides relevant information for selecting appropriate methods in future studies designed to investigate exercise thermoregulation in rats.
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Affiliation(s)
- Marcelo T. Andrade
- Exercise Physiology Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Karine N. O. Goulart
- Exercise Physiology Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Nicolas H. S. Barbosa
- Exercise Physiology Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Danusa D. Soares
- Exercise Physiology Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - André G. P. Andrade
- Biomechanics Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Dawit A. P. Gonçalves
- Exercise Physiology Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Thiago T. Mendes
- Department of Physical Education, Faculty of Education, Universidade Federal da Bahia, Salvador, Brazil
| | - Cândido C. Coimbra
- Laboratory of Endocrinology and Metabolism, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Samuel P. Wanner
- Exercise Physiology Laboratory, School of Physical Education, Physiotherapy and Occupational Therapy, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
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18
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Chun JH, Henckel MM, Knaub LA, Hull SE, Pott GB, Ramirez DG, Reusch JEB, Keller AC. (-)-Epicatechin Reverses Glucose Intolerance in Rats Housed at Thermoneutrality. PLANTA MEDICA 2022; 88:735-744. [PMID: 35777366 PMCID: PMC9343939 DOI: 10.1055/a-1843-9855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Accepted: 04/04/2022] [Indexed: 06/09/2023]
Abstract
Diabetes is a life-threatening and debilitating disease with pathological hallmarks, including glucose intolerance and insulin resistance. Plant compounds are a source of novel and effective therapeutics, and the flavonoid (-)-epicatechin, common to popular foods worldwide, has been shown to improve carbohydrate metabolism in both clinical studies and preclinical models. We hypothesized that (-)-epicatechin would alleviate thermoneutral housing-induced glucose intolerance. Male rats were housed at either thermoneutral (30 °C) or room temperature (24 °C) for 16 weeks and gavaged with either 1 mg/kg body weight or vehicle for the last 15 days before sacrifice. Rats housed at thermoneutrality had a significantly elevated serum glucose area under the curve (p < 0.05) and reduced glucose-mediated insulin secretion. In contrast, rats at thermoneutrality treated with (-)-epicatechin had improved glucose tolerance and increased insulin secretion (p < 0.05). Insulin tolerance tests revealed no differences in insulin sensitivity in any of the four groups. Pancreatic immunohistochemistry staining showed significantly greater islet insulin positive cells in animals housed at thermoneutrality. In conclusion, (-)-epicatechin improved carbohydrate tolerance via increased insulin secretion in response to glucose challenge without a change in insulin sensitivity.
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Affiliation(s)
- Ji Hye Chun
- Aquillius Corp., San Diego, CA, USA
- Rocky Mountain Regional VA Medical Center, Aurora, CO, USA
| | - Melissa M. Henckel
- Division of Endocrinology, Metabolism & Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
- Rocky Mountain Regional VA Medical Center, Aurora, CO, USA
| | - Leslie A. Knaub
- Division of Endocrinology, Metabolism & Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
- Rocky Mountain Regional VA Medical Center, Aurora, CO, USA
| | - Sara E. Hull
- Division of Endocrinology, Metabolism & Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
- Rocky Mountain Regional VA Medical Center, Aurora, CO, USA
| | - Greg B. Pott
- Division of Endocrinology, Metabolism & Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
- Rocky Mountain Regional VA Medical Center, Aurora, CO, USA
| | - David G. Ramirez
- Division of Endocrinology, Metabolism & Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
- Rocky Mountain Regional VA Medical Center, Aurora, CO, USA
| | - Jane E.-B. Reusch
- Division of Endocrinology, Metabolism & Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
- Rocky Mountain Regional VA Medical Center, Aurora, CO, USA
| | - Amy C. Keller
- Division of Endocrinology, Metabolism & Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO, USA
- Rocky Mountain Regional VA Medical Center, Aurora, CO, USA
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19
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James CM, Olejniczak SH, Repasky EA. How murine models of human disease and immunity are influenced by housing temperature and mild thermal stress. Temperature (Austin) 2022; 10:166-178. [PMID: 37332306 PMCID: PMC10274546 DOI: 10.1080/23328940.2022.2093561] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Revised: 06/16/2022] [Accepted: 06/17/2022] [Indexed: 10/17/2022] Open
Abstract
At the direction of The Guide and Use of Laboratory Animals, rodents in laboratory facilities are housed at ambient temperatures between 20°C and 26°C, which fall below their thermoneutral zone (TNZ). TNZ is identified as a range of ambient temperatures that allow an organism to regulate body temperature without employing additional thermoregulatory processes (e.g. metabolic heat production driven by norepinephrine), thus leading to mild, chronic cold stress. For mice, this chronic cold stress leads to increased serum levels of the catecholamine norepinephrine, which has direct effects on various immune cells and several aspects of immunity and inflammation. Here, we review several studies that have revealed that ambient temperature significantly impacts outcomes in various murine models of human diseases, particularly those in which the immune system plays a major role in its pathogenesis. The impact of ambient temperature on experimental outcomes raises questions regarding the clinical relevance of some murine models of human disease, since studies examining rodents housed within thermoneutral ambient temperatures revealed that rodent disease pathology more closely resembled that of humans. Unlike laboratory rodents, humans can modify their surroundings accordingly - by adjusting their clothing, the thermostat, or their physical activity - to live within the appropriate TNZ, offering a possible explanation for why many studies using murine models of human disease conducted at thermoneutrality better represent patient outcomes. Thus, it is strongly recommended that ambient housing temperature in such studies be consistently and accurately reported and recognized as an important experimental variable.
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Affiliation(s)
- Caitlin M. James
- Department of Immunology, Roswell Park Cancer Institute, Buffalo, NY, USA
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20
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Biancardi V, Patrone LGA, Vicente MC, Marques DA, Bicego KC, Funk GD, Gargaglioni LH. Prenatal fluoxetine has long lasting, differential effects on respiratory control in male and female rats. J Appl Physiol (1985) 2022; 133:371-389. [PMID: 35708704 DOI: 10.1152/japplphysiol.00020.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Serotonin (5-HT) is an important modulator of brain networks that control breathing. The selective serotonin reuptake inhibitor fluoxetine (FLX) is the first-line antidepressant drug prescribed during pregnancy. We investigated the effects of prenatal FLX on baseline breathing, ventilatory and metabolic responses to hypercapnia and hypoxia as well as number of brainstem 5-HT and tyrosine hydroxylase (TH) neurons of rats during postnatal development (P0-82). Prenatal FLX exposure of males showed a lower baseline that appeared in juveniles and remained in adulthood, with no sleep-wake state dependency. Prenatal FLX exposure of females did not affect baseline breathing. Juvenile male FLX rats showed increased CO2 and hypoxic ventilatory responses, normalizing by adulthood. Alterations in juvenile-FLX treated males were associated with greater number of 5-HT neurons in the ROB and RMAG. Adult FLX-exposed males showed greater number of 5-HT neurons in the RPA and TH neurons in the A5, while reduced number of TH neurons in A7. Prenatal FLX exposure of female rats was associated with greater hyperventilation induced by hypercapnia at P0-2 and juveniles whereas P12-14 and adult FLX (NREM sleep) rats showed an attenuation of the hypercapnic hyperventilation.FLX-exposed females had fewer 5-HT neurons in the RPA and reduced TH A6 density at P0-2; and greater number of TH neurons in the A7 at P12-14. These data indicate that prenatal FLX exposure affects the number of neurons of some monoaminergic regions in the brain and results in long lasting, sex specific changes in baseline breathing pattern and ventilatory responses to respiratory challenges.
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Affiliation(s)
- Vivian Biancardi
- Department of Animal Morphology and Physiology, Sao Paulo State University, Jaboticabal, Sao Paulo, Brazil.,Department of Physiology, Faculty of Medicine and Dentistry, Women and Children's Health Research Institute, Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, Canada
| | - Luis Gustavo A Patrone
- Department of Animal Morphology and Physiology, Sao Paulo State University, Jaboticabal, Sao Paulo, Brazil
| | - Mariane C Vicente
- Department of Animal Morphology and Physiology, Sao Paulo State University, Jaboticabal, Sao Paulo, Brazil
| | - Danuzia A Marques
- Department of Animal Morphology and Physiology, Sao Paulo State University, Jaboticabal, Sao Paulo, Brazil.,Department of Pediatrics, Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Quebec, QC, Canada
| | - Kênia C Bicego
- Department of Animal Morphology and Physiology, Sao Paulo State University, Jaboticabal, Sao Paulo, Brazil
| | - Gregory D Funk
- Department of Physiology, Faculty of Medicine and Dentistry, Women and Children's Health Research Institute, Neuroscience and Mental Health Institute, University of Alberta, Edmonton, AB, Canada
| | - Luciane H Gargaglioni
- Department of Animal Morphology and Physiology, Sao Paulo State University, Jaboticabal, Sao Paulo, Brazil
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21
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Nilsson S, Henriksson M, Berin E, Engblom D, Holm ACS, Hammar M. Resistance training reduced luteinising hormone levels in postmenopausal women in a substudy of a randomised controlled clinical trial: A clue to how resistance training reduced vasomotor symptoms. PLoS One 2022; 17:e0267613. [PMID: 35617333 PMCID: PMC9135255 DOI: 10.1371/journal.pone.0267613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 03/16/2022] [Indexed: 11/22/2022] Open
Abstract
Background Vasomotor symptoms (VMS) are common around menopause. Menopausal hormone therapy is the most effective treatment for VMS. Physical exercise has been proposed as an alternative treatment since physically active women have previously been found to experience fewer VMS than inactive women. In our randomised controlled trial on resistance training to treat VMS, sympoms were reduced by 50% in the intervention group compared with the control group. Objectives To propose a mechanism to explain how resistance training reduced VMS and to assess if luteinizing hormone (LH) and follicle stimulating hormone (FSH) were affected in accordance with the proposed mechanism. Trial design and methods A substudy of a randomized controlled trial on 65 postmenopausal women with VMS and low physical activity who were randomised to 15 weeks of resistance training three times per week (n = 33) or to a control group (n = 32). To be regarded compliant to the intervention we predecided a mean of two training sessions per week. The daily number of VMS were registered before and during the 15 weeks. Blood samples were drawn for analysis of LH and FSH at baseline and after 15 weeks. Results LH decreased significantly in the compliant intervention group compared with the control group (-4.0±10.6 versus 2.9±9.0, p = 0.028 with Mann-Whitney U test). FSH also decreased in the compliant intervention group compared with the control group, however not enough to reach statistical significance (-3.5±16.3 versus 3.2±18.2, p = 0.063 with Mann-Whitney U test). As previously published the number of hot flushes decreased significantly more in the intervention group than in the control group but there was no association between change in LH or FSH and in number of VMS. Conclusions We propose that endogenous opiods such as β-endorphin or dynorphin produced during resistance training decreased VMS by stimulating KNDγ-neurons to release neurokinin B to the hypothalamic thermoregulatory centre. Through effects on KNDγ-neurons, β-endorphin could also inhibit GnRH and thereby decrease the production of LH and FSH. The significanty decreased LH in the compliant intervention group compared with the control group was in accordance with the proposed mechanism.
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Affiliation(s)
- Sigrid Nilsson
- Obstetrics and Gynaecology, Division of Children’s and Women’s Health, Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Moa Henriksson
- Obstetrics and Gynaecology, Division of Children’s and Women’s Health, Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Emilia Berin
- Obstetrics and Gynaecology, Division of Children’s and Women’s Health, Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - David Engblom
- Division of Cell Biology, Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Anna-Clara Spetz Holm
- Obstetrics and Gynaecology, Division of Children’s and Women’s Health, Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Mats Hammar
- Obstetrics and Gynaecology, Division of Children’s and Women’s Health, Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
- * E-mail:
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22
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Reliability of physical performance and thermoregulatory parameters in rats subjected to incremental treadmill running. J Therm Biol 2022; 108:103270. [DOI: 10.1016/j.jtherbio.2022.103270] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 04/02/2022] [Accepted: 05/27/2022] [Indexed: 11/24/2022]
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Amorim MR, Foresti R, Benrahla DE, Motterlini R, Branco LGS. CORM-401, an orally active carbon monoxide-releasing molecule, increases body temperature by activating non-shivering thermogenesis in rats. Temperature (Austin) 2022; 9:310-317. [PMID: 36339088 PMCID: PMC9629103 DOI: 10.1080/23328940.2022.2061270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Abstract
Thermoregulation is critical in health and disease and is tightly controlled to maintain body temperature homeostasis. Carbon monoxide (CO), an endogenous gasotransmitter produced during heme degradation by heme oxygenases, has been suggested to play a role in body core temperature (Tb) regulation. However, a direct involvement of CO in thermoregulation has not been confirmed and its mechanism(s) of action remain largely unknown. In the present study we characterized the effects of systemic delivery of CO by administration of an orally active CO-releasing molecule (CORM-401) on Tb regulation in conscious freely moving rats. Specifically, we evaluated the main thermo effectors in rats treated with CORM-401 by assessing: (i) non-shivering thermogenesis, i.e. the increased metabolism of brown fat measured through oxygen consumption and (ii) the rate of heat loss from the tail through calculations of heat loss index. We found that oral administration of CORM-401 (30 mg/kg) resulted in augmented CO delivery into the blood circulation as evidenced a by significant increase in carbon monoxy hemoglobin levels(COHb). In addition, treatment with CORM-401 increased Tb, which was caused by an elevated non-shivering thermogenesis indicated by increased oxygen consumption without significant changes in the tail heat loss. On the other hand, CORM-401 did not affect blood pressure, but significantly decreased heart rate. In summary, the findings of the present study reveal that increased circulating CO levels lead to a rise in Tb, which could have important implications in the emerging role of CO in the modulation of energetic metabolism.
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Affiliation(s)
- Mateus R. Amorim
- Dental School of Ribeirão Preto, University of São Paulo, São Paulo, Brazil
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Roberta Foresti
- Faculty of Health, University Paris Est Créteil, INSERM, IMRB, Créteil, France
| | | | - Roberto Motterlini
- Faculty of Health, University Paris Est Créteil, INSERM, IMRB, Créteil, France
| | - Luiz G. S. Branco
- Dental School of Ribeirão Preto, University of São Paulo, São Paulo, Brazil
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24
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Chun JH, Henckel MM, Knaub LA, Hull SE, Pott GB, Walker LA, Reusch JEB, Keller AC. (-)-Epicatechin Improves Vasoreactivity and Mitochondrial Respiration in Thermoneutral-Housed Wistar Rat Vasculature. Nutrients 2022; 14:nu14051097. [PMID: 35268072 PMCID: PMC8912787 DOI: 10.3390/nu14051097] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 02/12/2022] [Accepted: 02/19/2022] [Indexed: 12/22/2022] Open
Abstract
Cardiovascular disease (CVD) is a global health concern. Vascular dysfunction is an aspect of CVD, and novel treatments targeting vascular physiology are necessary. In the endothelium, eNOS regulates vasodilation and mitochondrial function; both are disrupted in CVD. (−)-Epicatechin, a botanical compound known for its vasodilatory, eNOS, and mitochondrial-stimulating properties, is a potential therapy in those with CVD. We hypothesized that (−)-epicatechin would support eNOS activity and mitochondrial respiration, leading to improved vasoreactivity in a thermoneutral-derived rat model of vascular dysfunction. We housed Wistar rats at room temperature or in thermoneutral conditions for a total of 16 week and treated them with 1mg/kg body weight (−)-epicatechin for 15 day. Vasoreactivity, eNOS activity, and mitochondrial respiration were measured, in addition to the protein expression of upstream cellular signaling molecules including AMPK and CaMKII. We observed a significant improvement of vasodilation in those housed in thermoneutrality and treated with (−)-epicatechin (p < 0.05), as well as dampened mitochondrial respiration (p < 0.05). AMPK and CaMKIIα and β expression were lessened with (−)-epicatechin treatment in those housed at thermoneutrality (p < 0.05). The opposite was observed with animals housed at room temperature supplemented with (−)-epicatechin. These data illustrate a context-dependent vascular response to (−)-epicatechin, a candidate for CVD therapeutic development.
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Affiliation(s)
- Ji Hye Chun
- Microtek, Inc., San Diego, CA 92127, USA;
- Rocky Mountain Regional VA Medical Center, Aurora, CO 80045, USA; (M.M.H.); (L.A.K.); (S.E.H.); (G.B.P.); (J.E.-B.R.)
| | - Melissa M. Henckel
- Rocky Mountain Regional VA Medical Center, Aurora, CO 80045, USA; (M.M.H.); (L.A.K.); (S.E.H.); (G.B.P.); (J.E.-B.R.)
- Division of Endocrinology, Metabolism & Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Leslie A. Knaub
- Rocky Mountain Regional VA Medical Center, Aurora, CO 80045, USA; (M.M.H.); (L.A.K.); (S.E.H.); (G.B.P.); (J.E.-B.R.)
- Division of Endocrinology, Metabolism & Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Sara E. Hull
- Rocky Mountain Regional VA Medical Center, Aurora, CO 80045, USA; (M.M.H.); (L.A.K.); (S.E.H.); (G.B.P.); (J.E.-B.R.)
- Division of Endocrinology, Metabolism & Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Greg B. Pott
- Rocky Mountain Regional VA Medical Center, Aurora, CO 80045, USA; (M.M.H.); (L.A.K.); (S.E.H.); (G.B.P.); (J.E.-B.R.)
- Division of Endocrinology, Metabolism & Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Lori A. Walker
- Division of Cardiology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA;
| | - Jane E.-B. Reusch
- Rocky Mountain Regional VA Medical Center, Aurora, CO 80045, USA; (M.M.H.); (L.A.K.); (S.E.H.); (G.B.P.); (J.E.-B.R.)
- Division of Endocrinology, Metabolism & Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Amy C. Keller
- Rocky Mountain Regional VA Medical Center, Aurora, CO 80045, USA; (M.M.H.); (L.A.K.); (S.E.H.); (G.B.P.); (J.E.-B.R.)
- Division of Endocrinology, Metabolism & Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
- Correspondence: ; Tel.: +1-303-724-3921
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25
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do Amaral-Silva L, da Silva WC, Gargaglioni LH, Bícego KC. Metabolic trade-offs favor regulated hypothermia and inhibit fever in immune-challenged chicks. J Exp Biol 2022; 225:274497. [DOI: 10.1242/jeb.243115] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 01/24/2022] [Indexed: 11/20/2022]
Abstract
The febrile response to resist a pathogen is energetically expensive while regulated hypothermia seems to preserve energy for vital functions. We hypothesized here that immune challenged birds under metabolic trade-offs (reduced energy supply / increased energy demand) favor a regulated hypothermic response at the expense of fever. To test this hypothesis, we compared 5-days old broiler chicks exposed to fasting, cold (25oC), and fasting combined with cold to a control group fed at thermoneutral condition (30oC). The chicks were injected with saline or with a high dose of endotoxin known to induce a biphasic thermal response composed of body temperature (Tb) drop followed by fever. Then Tb, oxygen consumption (metabolic rate), peripheral vasomotion (cutaneous heat exchange), breathing frequency (respiratory heat exchange), and huddling behavior (heat conservation indicator) were analyzed. Irrespective of metabolic trade-offs, chicks presented a transient regulated hypothermia in the first hour, which relied on a suppressed metabolic rate for all groups, increased breathing frequency for chicks fed/fasted at 30oC, and peripheral vasodilation in fed/fasted chicks at 25oC. Fever was observed only in chicks kept at thermoneutrality and was supported by peripheral vasoconstriction and huddling behavior. Fed and fasted chicks at 25oC completely eliminated fever despite the ability to increase metabolic rate for thermogenesis in the phase correspondent to fever when it was pharmacologically induced by 2.4-Dinitrophenol. Our data suggest that increased competing demands affect chicks’ response to an immune challenge favoring regulated hypothermia to preserve energy while the high costs of fever to resist a pathogen are avoided.
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Affiliation(s)
- Lara do Amaral-Silva
- Department of Animal Morphology and Physiology, São Paulo State University (FCAV-UNESP), Jaboticabal, SP, Brazil
- Department of Biology, University of North Carolina at Greensboro (UNCG), Greensboro, NC, USA
| | - Welex Cândido da Silva
- Department of Animal Morphology and Physiology, São Paulo State University (FCAV-UNESP), Jaboticabal, SP, Brazil
| | - Luciane Helena Gargaglioni
- Department of Animal Morphology and Physiology, São Paulo State University (FCAV-UNESP), Jaboticabal, SP, Brazil
| | - Kênia Cardoso Bícego
- Department of Animal Morphology and Physiology, São Paulo State University (FCAV-UNESP), Jaboticabal, SP, Brazil
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26
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Keringer P, Furedi N, Gaszner B, Miko A, Pakai E, Fekete K, Olah E, Kelava L, Romanovsky AA, Rumbus Z, Garami A. The hyperthermic effect of central cholecystokinin is mediated by the cyclooxygenase-2 pathway. Am J Physiol Endocrinol Metab 2022; 322:E10-E23. [PMID: 34779255 DOI: 10.1152/ajpendo.00223.2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Cholecystokinin (CCK) increases core body temperature via CCK2 receptors when administered intracerebroventricularly (icv). The mechanisms of CCK-induced hyperthermia are unknown, and it is also unknown whether CCK contributes to the fever response to systemic inflammation. We studied the interaction between central CCK signaling and the cyclooxygenase (COX) pathway. Body temperature was measured in adult male Wistar rats pretreated with intraperitoneal infusion of the nonselective COX enzyme inhibitor metamizol (120 mg/kg) or a selective COX-2 inhibitor, meloxicam, or etoricoxib (10 mg/kg for both) and, 30 min later, treated with intracerebroventricular CCK (1.7 µg/kg). In separate experiments, CCK-induced neuronal activation (with and without COX inhibition) was studied in thermoregulation- and feeding-related nuclei with c-Fos immunohistochemistry. CCK increased body temperature by ∼0.4°C from 10 min postinfusion, which was attenuated by metamizol. CCK reduced the number of c-Fos-positive cells in the median preoptic area (by ∼70%) but increased it in the dorsal hypothalamic area and in the rostral raphe pallidus (by ∼50% in both); all these changes were completely blocked with metamizol. In contrast, CCK-induced satiety and neuronal activation in the ventromedial hypothalamus were not influenced by metamizol. CCK-induced hyperthermia was also completely blocked with both selective COX-2 inhibitors studied. Finally, the CCK2 receptor antagonist YM022 (10 µg/kg icv) attenuated the late phases of fever induced by bacterial lipopolysaccharide (10 µg/kg; intravenously). We conclude that centrally administered CCK causes hyperthermia through changes in the activity of "classical" thermoeffector pathways and that the activation of COX-2 is required for the development of this response.NEW & NOTEWORTHY An association between central cholecystokinin signaling and the cyclooxygenase-prostaglandin E pathway has been proposed but remained poorly understood. We show that the hyperthermic response to the central administration of cholecystokinin alters the neuronal activity within efferent thermoeffector pathways and that these effects are fully blocked by the inhibition of cyclooxygenase. We also show that the activation of cyclooxygenase-2 is required for the hyperthermic effect of cholecystokinin and that cholecystokinin is a modulator of endotoxin-induced fever.
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Affiliation(s)
- Patrik Keringer
- Department of Thermophysiology, Institute for Translational Medicine, Medical School, University of Pécs, Pécs, Hungary
| | - Nora Furedi
- Department of Anatomy, Research Group for Mood Disorders, Centre for Neuroscience, Medical School and Szentagothai Research Centre, University of Pécs, Pécs, Hungary
| | - Balazs Gaszner
- Department of Anatomy, Research Group for Mood Disorders, Centre for Neuroscience, Medical School and Szentagothai Research Centre, University of Pécs, Pécs, Hungary
| | - Alexandra Miko
- Institute for Translational Medicine, Medical School and Szentagothai Research Centre, University of Pécs, Pécs, Hungary
| | - Eszter Pakai
- Department of Thermophysiology, Institute for Translational Medicine, Medical School, University of Pécs, Pécs, Hungary
| | - Kata Fekete
- Department of Thermophysiology, Institute for Translational Medicine, Medical School, University of Pécs, Pécs, Hungary
| | - Emoke Olah
- Department of Thermophysiology, Institute for Translational Medicine, Medical School, University of Pécs, Pécs, Hungary
| | - Leonardo Kelava
- Department of Thermophysiology, Institute for Translational Medicine, Medical School, University of Pécs, Pécs, Hungary
| | | | - Zoltan Rumbus
- Department of Thermophysiology, Institute for Translational Medicine, Medical School, University of Pécs, Pécs, Hungary
| | - Andras Garami
- Department of Thermophysiology, Institute for Translational Medicine, Medical School, University of Pécs, Pécs, Hungary
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27
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Thermoregulatory significance of immobility in the forced swim test. Physiol Behav 2022; 247:113709. [DOI: 10.1016/j.physbeh.2022.113709] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Revised: 12/31/2021] [Accepted: 01/18/2022] [Indexed: 11/19/2022]
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Suwannapaporn P, Chaiyabutr N, Wanasuntronwong A, Thammacharoen S. Arcuate proopiomelanocortin is part of a novel neural connection for short-term low-degree of high ambient temperature effects on food intake. Physiol Behav 2021; 245:113687. [PMID: 34942196 DOI: 10.1016/j.physbeh.2021.113687] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 12/16/2021] [Accepted: 12/17/2021] [Indexed: 11/26/2022]
Abstract
High ambient temperature (HTa) is an important environmental factor influencing food intake (FI). We previously demonstrated that low-degree HTa exposure decreased FI earlier than activated physiological responses, and this effect was related to the median preoptic nucleus (MnPO) and arcuate nucleus (Arc) connection. The present study refines the condition of low-degree HTa exposure and focuses on the mechanism of Arc neural activation. We demonstrated in the first experiment that with the usual ambient temperature (Ta) at 23 °C, the low degree HTa condition is at a 7 °C temperature difference and with 90 min exposure. Rats exposed to this short-term low-degree HTa had significantly lower 1-h FI than those exposed to control Ta (CTa) without differences in rectal temperature and hematocrit. Under nonfeeding conditions, HTa could enhance c-Fos at the Arc without the activation of proopiomelanocortin (POMC) neurons. Under feeding conditions, HTa could enhance both c-Fos and POMC at Arc. In addition, the number of c-Fos and POMC colocalizations in the HTa group was higher than that in the CTa group. Finally, intracerebral preinfusion with a subthreshold dose of the melanocortin antagonist SHU9119 reversed the effect of low-degree HTa exposure on FI. Therefore, we conclude that the effect of short-term low-degree HTa exposure on FI in rats is mediated in part by activation of POMC neurons at the Arc. The results partially support the hypothesis that Arc is a crucial hypothalamic nucleus for the effect of low-degree HTa exposure on FI.
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Affiliation(s)
- Pornsiri Suwannapaporn
- Department of Physiology, Faculty of Veterinary Science, Chulalongkorn University, Pathumwan, Bangkok 10330, Thailand
| | - Narongsak Chaiyabutr
- Department of Physiology, Faculty of Veterinary Science, Chulalongkorn University, Pathumwan, Bangkok 10330, Thailand; Queen Saovabha Memorial Institute, The Thai Red Cross Society, Bangkok 10330, Thailand; The Academy of Science, The Royal Society of Thailand, Dusit, Bangkok 10300, Thailand
| | - Aree Wanasuntronwong
- Department of oral biology, Faculty of Dentistry, Mahidol University, Ratchathewi, Bangkok 10400, Thailand
| | - Sumpun Thammacharoen
- Department of Physiology, Faculty of Veterinary Science, Chulalongkorn University, Pathumwan, Bangkok 10330, Thailand.
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Rocha M, Serronha A, Rodrigues M, Alves PC, Monterroso P. Comfort over safety: thermoregulation overshadows predation risk effects in the activity of a keystone prey. J Zool (1987) 2021. [DOI: 10.1111/jzo.12947] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- M. Rocha
- Escola de Ciências Universidade do Minho Braga Portugal
| | - A. Serronha
- Centro de Investigação em Biodiversidade e Recursos Genéticos InBIO Laboratório Associado Universidade do Porto CIBIO Vairão Portugal
- BIOPOLIS Program in Genomics Biodiversity and Land Planning CIBIO Vairão Portugal
| | - M. Rodrigues
- Centro de Investigação em Biodiversidade e Recursos Genéticos InBIO Laboratório Associado Universidade do Porto CIBIO Vairão Portugal
- BIOPOLIS Program in Genomics Biodiversity and Land Planning CIBIO Vairão Portugal
- Estação Biológica de Mértola (EBM) Mértola Portugal
| | - P. C. Alves
- Centro de Investigação em Biodiversidade e Recursos Genéticos InBIO Laboratório Associado Universidade do Porto CIBIO Vairão Portugal
- BIOPOLIS Program in Genomics Biodiversity and Land Planning CIBIO Vairão Portugal
- Estação Biológica de Mértola (EBM) Mértola Portugal
- Departamento de Biologia Faculdade de Ciências Universidade do Porto Porto Portugal
- Wildlife Biology Program Department of Ecosystem and Conservation Sciences W.A. Franke College of Forestry and Conservation University of Montana Missoula MT USA
| | - P. Monterroso
- Centro de Investigação em Biodiversidade e Recursos Genéticos InBIO Laboratório Associado Universidade do Porto CIBIO Vairão Portugal
- BIOPOLIS Program in Genomics Biodiversity and Land Planning CIBIO Vairão Portugal
- Estação Biológica de Mértola (EBM) Mértola Portugal
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A newly discovered behavior ('tail-belting') among wild rodents in sub zero conditions. Sci Rep 2021; 11:22449. [PMID: 34789796 PMCID: PMC8599740 DOI: 10.1038/s41598-021-01833-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 10/28/2021] [Indexed: 11/08/2022] Open
Abstract
Rodents are among the most successful mammals because they have the ability to adapt to a broad range of environmental conditions. Here, we present the first record of a previously unknown thermal adaptation to cold stress that repeatedly occurred in two species of non-commensal rodents (Apodemus flavicollis and Apodemus agrarius). The classic rodent literature implies that rodents prevent heat loss via a broad range of behavioral adaptations including sheltering, sitting on their tails, curling into a ball, or huddling with conspecifics. Here, we have repeatedly observed an undescribed behavior which we refer to as “tail-belting”. This behavior was performed under cold stress, whereby animals lift and curl the tail medially, before resting it on the dorsal, medial rump while feeding or resting. We documented 115 instances of the tail-belting behavior; 38 in Apodemus agrarius, and 77 in Apodemus flavicollis. Thermal imaging data show the tails remained near ambient temperature even when temperatures were below 0 °C. Since the tail-belting occurred only when the temperature dropped below − 6.9 °C (for A. flavicollis) and − 9.5 °C (for A. agrarius), we surmise that frostbite prevention may be the primary reason for this adaptation. It is likely that tail-belting has not previously been documented because free-ranging mice are rarely-recorded in the wild under extreme cold conditions. Given that these animals are so closely-related to laboratory rodents, this knowledge could potentially be relevant to researchers in various disciplines. We conclude by setting several directions for future research in this area.
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The Hypothermic Effect of Hydrogen Sulfide Is Mediated by the Transient Receptor Potential Ankyrin-1 Channel in Mice. Pharmaceuticals (Basel) 2021; 14:ph14100992. [PMID: 34681216 PMCID: PMC8538668 DOI: 10.3390/ph14100992] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 09/24/2021] [Accepted: 09/25/2021] [Indexed: 12/17/2022] Open
Abstract
Hydrogen sulfide (H2S) has been shown in previous studies to cause hypothermia and hypometabolism in mice, and its thermoregulatory effects were subsequently investigated. However, the molecular target through which H2S triggers its effects on deep body temperature has remained unknown. We investigated the thermoregulatory response to fast-(Na2S) and slow-releasing (GYY4137) H2S donors in C57BL/6 mice, and then tested whether their effects depend on the transient receptor potential ankyrin-1 (TRPA1) channel in Trpa1 knockout (Trpa1−/−) and wild-type (Trpa1+/+) mice. Intracerebroventricular administration of Na2S (0.5–1 mg/kg) caused hypothermia in C57BL/6 mice, which was mediated by cutaneous vasodilation and decreased thermogenesis. In contrast, intraperitoneal administration of Na2S (5 mg/kg) did not cause any thermoregulatory effect. Central administration of GYY4137 (3 mg/kg) also caused hypothermia and hypometabolism. The hypothermic response to both H2S donors was significantly (p < 0.001) attenuated in Trpa1−/− mice compared to their Trpa1+/+ littermates. Trpa1 mRNA transcripts could be detected with RNAscope in hypothalamic and other brain neurons within the autonomic thermoeffector pathways. In conclusion, slow- and fast-releasing H2S donors induce hypothermia through hypometabolism and cutaneous vasodilation in mice that is mediated by TRPA1 channels located in the brain, presumably in hypothalamic neurons within the autonomic thermoeffector pathways.
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Inhibition of nNOS in the paraventricular nucleus of hypothalamus decreases exercise-induced hyperthermia. Brain Res Bull 2021; 177:64-72. [PMID: 34536522 DOI: 10.1016/j.brainresbull.2021.09.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 08/21/2021] [Accepted: 09/10/2021] [Indexed: 11/23/2022]
Abstract
The paraventricular nucleus of the hypothalamus (PVN) is an important site for autonomic control, which integrates thermoregulation centers and sympathetic outflow to thermoeffector organs. PVN neurons express the neuronal isoform of nitric oxide synthase (nNOS) whose expression is locally upregulated by physical exercise. Thus, the aim of the present study was to evaluate the role of nNOS in the PVN in the exercise-induced hyperthermia. Seven days after surgery, male Wistar rats received bilateral intra-PVN microinjections of the selective nNOS inhibitor Nw-Propyl-L-Arginine (NPLA) or vehicle (saline) and were submitted to an acute progressive exercise session on a treadmill until fatigue. Abdominal and tail skin temperature (Tabd and Ttail, respectively) were measured, and the threshold (Hthr; °C) and sensitivity (Hsen) for heat dissipation calculated. Performance variables were also collected. During the progressive exercise protocol, all animals displayed an increase in the Tabd. However, compared to vehicle group, the microinjection of NPLA in the PVN attenuated the exercise-induced hyperthermia. There was no difference in Ttail or Hthr between NPLA and control rats. In contrast, Hsen was increased in the NPLA group compared to vehicle. In addition, heat storage was lower in NPLA-treated animals. Despite the temperature differences, inhibition of nNOS in the PVN did not affect running performance on the treadmill. These results suggest that nitrergic signaling within the PVN, under nNOS activation, drives the increase of body temperature, being necessary for the proper thermal regulatory mechanisms during progressive exercise-induced hyperthermia.
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Mota-Rojas D, Pereira AMF, Wang D, Martínez-Burnes J, Ghezzi M, Hernández-Avalos I, Lendez P, Mora-Medina P, Casas A, Olmos-Hernández A, Domínguez A, Bertoni A, Geraldo ADM. Clinical Applications and Factors Involved in Validating Thermal Windows Used in Infrared Thermography in Cattle and River Buffalo to Assess Health and Productivity. Animals (Basel) 2021; 11:2247. [PMID: 34438705 PMCID: PMC8388381 DOI: 10.3390/ani11082247] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 07/16/2021] [Accepted: 07/27/2021] [Indexed: 02/04/2023] Open
Abstract
Infrared thermography (IRT) is a non-ionizing, non-invasive technique that permits evaluating the comfort levels of animals, a topic of concern due to the growing interest in determining the state of health and welfare of production animals. The operating principle of IRT is detecting the heat irradiated in anatomical regions characterized by a high density of near-surface blood vessels that can regulate temperature gain or loss from/to the environment by modifying blood flow. This is essential for understanding the various vascular thermoregulation mechanisms of different species, such as rodents and ruminants' tails. The usefulness of ocular, nasal, and vulvar thermal windows in the orbital (regio orbitalis), nasal (regio nasalis), and urogenital (regio urogenitalis) regions, respectively, has been demonstrated in cattle. However, recent evidence for the river buffalo has detected discrepancies in the data gathered from distinct thermal regions in these large ruminants, suggesting a limited sensitivity and specificity when used with this species due to various factors: the presence of hair, ambient temperature, and anatomical features, such as skin thickness and variations in blood supplies to different regions. In this review, a literature search was conducted in Scopus, Web of Science, ScienceDirect, and PubMed, using keyword combinations that included "infrared thermography", "water buffalo", "river buffalo" "thermoregulation", "microvascular changes", "lacrimal caruncle", "udder", "mastitis", and "nostril". We discuss recent findings on four thermal windows-the orbital and nasal regions, mammary gland in the udder region (regio uberis), and vulvar in the urogenital region (regio urogenitalis)-to elucidate the factors that modulate and intervene in validating thermal windows and interpreting the information they provide, as it relates to the clinical usefulness of IRT for cattle (Bos) and the river buffalo (Bubalus bubalis).
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Affiliation(s)
- Daniel Mota-Rojas
- Neurophysiology, Behavior and Animal Welfare Assessment, DPAA, Universidad Autónoma Metropolitana (UAM), Unidad Xochimilco, Mexico City 04960, Mexico; (A.C.); (A.D.); (A.B.)
| | - Alfredo M. F. Pereira
- Mediterranean Institute for Agriculture, Environment and Development (MED), Institute for Advanced Studies and Research, Universidade de Évora, Pólo da Mitra, Ap. 94, 7006-554 Évora, Portugal;
| | - Dehua Wang
- School of Life Sciences, Shandong University, Qingdao 266237, China;
| | - Julio Martínez-Burnes
- Animal Health Group, Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Tamaulipas, Victoria City 87000, Mexico;
| | - Marcelo Ghezzi
- Animal Welfare Area, Faculty of Veterinary Sciences (FCV), Universidad Nacional del Centro de la Provincia de Buenos Aires (UNCPBA), Buenos Aires 7000, Argentina; (M.G.); (P.L.)
| | - Ismael Hernández-Avalos
- Facultad de Estudios Superiores Cuautitlán, Universidad Nacional Autónoma de México (UNAM), Cuautitlan Izcalli 54714, Mexico; (I.H.-A.); (P.M.-M.)
| | - Pamela Lendez
- Animal Welfare Area, Faculty of Veterinary Sciences (FCV), Universidad Nacional del Centro de la Provincia de Buenos Aires (UNCPBA), Buenos Aires 7000, Argentina; (M.G.); (P.L.)
| | - Patricia Mora-Medina
- Facultad de Estudios Superiores Cuautitlán, Universidad Nacional Autónoma de México (UNAM), Cuautitlan Izcalli 54714, Mexico; (I.H.-A.); (P.M.-M.)
| | - Alejandro Casas
- Neurophysiology, Behavior and Animal Welfare Assessment, DPAA, Universidad Autónoma Metropolitana (UAM), Unidad Xochimilco, Mexico City 04960, Mexico; (A.C.); (A.D.); (A.B.)
| | - Adriana Olmos-Hernández
- Division of Biotechnology—Bioterio and Experimental Surgery, Instituto Nacional de Rehabilitación-Luis Guillermo Ibarra (INR-LGII), Tlalpan, Mexico City 14389, Mexico;
| | - Adriana Domínguez
- Neurophysiology, Behavior and Animal Welfare Assessment, DPAA, Universidad Autónoma Metropolitana (UAM), Unidad Xochimilco, Mexico City 04960, Mexico; (A.C.); (A.D.); (A.B.)
| | - Aldo Bertoni
- Neurophysiology, Behavior and Animal Welfare Assessment, DPAA, Universidad Autónoma Metropolitana (UAM), Unidad Xochimilco, Mexico City 04960, Mexico; (A.C.); (A.D.); (A.B.)
| | - Ana de Mira Geraldo
- Mediterranean Institute for Agriculture, Environment and Development (MED), Institute for Advanced Studies and Research, Universidade de Évora, Pólo da Mitra, Ap. 94, 7006-554 Évora, Portugal;
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Mai TC, Braun A, Bach V, Pelletier A, de Seze R. Low-Level Radiofrequency Exposure Induces Vasoconstriction in Rats. Bioelectromagnetics 2021; 42:455-463. [PMID: 34015144 DOI: 10.1002/bem.22350] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 05/04/2021] [Accepted: 05/09/2021] [Indexed: 11/07/2022]
Abstract
Recent studies have revealed that rodents' physiological responses to low-intensity radiofrequency (RF) electromagnetic fields were similar to thermoregulatory responses to cold conditions. The primary autonomic response to cold exposure is peripheral vasoconstriction that allows rodents to reduce heat loss and maintain a relatively constant internal body temperature. In the present study, we investigated the effects of 900 MHz RF at a low level (SAR of 0.35 W/kg) on tail skin temperature (Ttail ) in rats. We showed that rats exposed to RF had lower Ttail than control rats at ambient temperatures between 27 and 28 °C, suggesting that RF could induce a noticeable degree of vasoconstriction under mild-warm ambient temperatures. This difference in Ttail was suppressed after the intraperitoneal injection of a vasodilator, an α-adrenergic antagonist, confirming the hypothesis of the vasoconstriction in exposed rats. Moreover, like a response to cold stimuli, RF exposure led to increased plasma concentrations of important factors: noradrenaline (a neurotransmitter responsible for vasoconstriction and thermogenesis) and fatty acids (markers of activated thermogenesis). Taken together, these findings indicate that low-intensity RF levels triggered some key physiological events usually associated with responses to cold in rats. © 2021 Bioelectromagnetics Society.
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Affiliation(s)
- Thi Cuc Mai
- Experimental Toxicology Unit, National Institute of Industrial Environment and Risks (INERIS), Parc Technologique Alata, Verneuil-en-Halatte, France.,PeriTox Laboratory, UMR-I 01 INERIS, Picardie Jules Verne University, Amiens, France
| | - Anne Braun
- Experimental Toxicology Unit, National Institute of Industrial Environment and Risks (INERIS), Parc Technologique Alata, Verneuil-en-Halatte, France.,PeriTox Laboratory, UMR-I 01 INERIS, Picardie Jules Verne University, Amiens, France
| | - Veronique Bach
- Experimental Toxicology Unit, National Institute of Industrial Environment and Risks (INERIS), Parc Technologique Alata, Verneuil-en-Halatte, France.,PeriTox Laboratory, UMR-I 01 INERIS, Picardie Jules Verne University, Amiens, France
| | - Amandine Pelletier
- Experimental Toxicology Unit, National Institute of Industrial Environment and Risks (INERIS), Parc Technologique Alata, Verneuil-en-Halatte, France.,PeriTox Laboratory, UMR-I 01 INERIS, Picardie Jules Verne University, Amiens, France
| | - Rene de Seze
- Experimental Toxicology Unit, National Institute of Industrial Environment and Risks (INERIS), Parc Technologique Alata, Verneuil-en-Halatte, France.,PeriTox Laboratory, UMR-I 01 INERIS, Picardie Jules Verne University, Amiens, France
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35
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Amaral-Silva LD, Gargaglioni LH, Steiner AA, Oliveira MT, Bícego KC. Regulated hypothermia in response to endotoxin in birds. J Physiol 2021; 599:2969-2986. [PMID: 33823064 DOI: 10.1113/jp281385] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Accepted: 03/23/2021] [Indexed: 01/13/2023] Open
Abstract
KEY POINTS The costs associated with immune and thermal responses may exceed the benefits to the host during severe inflammation. In this case, regulated hypothermia instead of fever can occur in rodents as a beneficial strategy to conserve energy for vital functions with consequent tissue protection and hypoxia prevention. We tested the hypothesis that this phenomenon is not exclusive to mammals, but extends to the other endothermic group, birds. A decrease in metabolic rate without any failure in mitochondrial respiration, nor oxygen delivery, is the main evidence supporting the regulated nature of endotoxin-induced hypothermia in chicks. Thermolytic mechanisms such as tachypnea and cutaneous vasodilatation can also be recruited to facilitate body temperature decrease under lipopolysaccharide treatment, especially in the cold. Our findings bring a new perspective for evolutionary medicine studies on energy trade-off in host defence because regulated hypothermia may be a phenomenon spread among vertebrates facing a severe immune challenge. ABSTRACT A switch from fever to regulated hypothermia can occur in mammals under circumstances of reduced physiological fitness (e.g. sepsis) to direct energy to defend vital systems. Birds in which the cost to resist a pathogen is additive to the highest metabolic rate and body temperature (Tb ) among vertebrates may also benefit from regulated hypothermia during systemic inflammation. Here, we show that the decrease in Tb observed during an immune challenge in birds is a regulated hypothermia, and not a result of metabolic failure. We investigated O2 consumption (thermogenesis index), ventilation (respiratory heat loss), skin temperature (sensible heat loss) and muscle mitochondrial respiration (thermogenic tissue) during Tb fall in chicken chicks challenged with endotoxin [lipopolysaccharide (LPS)]. Chicks injected with LPS were also tested regarding the capacity to raise O2 consumption to meet an increased demand driven by 2,4-dinitrophenol. LPS decreased Tb and the metabolic rate of chicks without affecting muscle uncoupled, coupled and non-coupled mitochondrial respiration. LPS-challenged chicks were indeed capable of increasing metabolic rate in response to 2,4-dinitrophenol, indicating no O2 delivery limitation. Additionally, chicks did not attempt to prevent Tb from falling during hypothermia but, instead, activated cutaneous and respiratory thermolytic mechanisms, providing an additional cooling force. These data provide the first evidence of the regulated nature of the hypothermic response to endotoxin in birds. Therefore, it changes the current understanding of bird's thermoregulation during severe inflammation, indicating that regulated hypothermia is either a convergent trait for endotherms or a conserved response among vertebrates, which adds a new perspective for evolutionary medicine research.
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Affiliation(s)
- Lara do Amaral-Silva
- Department of Animal Morphology and Physiology, São Paulo State University, Jaboticabal, SP, Brazil
| | - Luciane H Gargaglioni
- Department of Animal Morphology and Physiology, São Paulo State University, Jaboticabal, SP, Brazil
| | - Alexandre A Steiner
- Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Marcos T Oliveira
- Department of Technology, São Paulo State University, Jaboticabal, SP, Brazil
| | - Kênia Cardoso Bícego
- Department of Animal Morphology and Physiology, São Paulo State University, Jaboticabal, SP, Brazil
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Dantas MRT, Souza-Junior JBF, Castelo TDS, Lago AEDA, Silva AR. Understanding how environmental factors influence reproductive aspects of wild myomorphic and hystricomorphic rodents. Anim Reprod 2021; 18:e20200213. [PMID: 33936293 PMCID: PMC8078862 DOI: 10.1590/1984-3143-ar2020-0213] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Accepted: 02/15/2021] [Indexed: 12/24/2022] Open
Abstract
Myomorphic and hystricomorphic rodents are vital for maintaining various ecosystems around the planet. This review enables a better understanding of how these rodents respond to environmental factors and adapt to climate adversities. Innumerable factors, such as photoperiod, rainfall, and temperature, can impair or contribute to the quality of rodent reproductive parameters. Prolonged animal exposure to high ambient temperatures alters thermoregulation mechanisms and causes testicular and ovarian tissue degeneration and hormonal deregulation. Photoperiod influences the biological circannual rhythm and reproductive cycles of rodents because it strongly regulates melatonin secretion by the pineal gland, which modulates gonadotropic hormone secretion. Rainfall quantity directly regulates the abundance of fruits in an ecosystem, which modulates the reproductive seasonality of species which are most dependent on a seasonal fruit-based diet. Species with a more diversified fruit diet have smaller reproductive seasonality. As such, habitats are chosen by animals for various reasons, including the availability of food, sexual partners, intra-and inter-specific competition, and predation. This knowledge allows us to monitor and establish management plans to aid in conservation strategies for wild rodent species.
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Affiliation(s)
- Maiko Roberto Tavares Dantas
- Laboratório de Conservação de Germoplasma Animal, Universidade Federal Rural do Semi-Árido - UFERSA, Mossoró, RN, Brasil
| | | | - Thibério de Souza Castelo
- Laboratório de Biometeorologia e Biofísica Ambiental, Universidade Federal Rural do Semi-Árido - UFERSA, Mossoró, RN, Brasil
| | - Arthur Emannuel de Araújo Lago
- Laboratório de Conservação de Germoplasma Animal, Universidade Federal Rural do Semi-Árido - UFERSA, Mossoró, RN, Brasil
| | - Alexandre Rodrigues Silva
- Laboratório de Conservação de Germoplasma Animal, Universidade Federal Rural do Semi-Árido - UFERSA, Mossoró, RN, Brasil
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37
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Cristina-Silva C, Gargaglioni LH, Bícego KC. A thermoregulatory role of the medullary raphe in birds. J Exp Biol 2021; 224:jeb.234344. [PMID: 33758021 DOI: 10.1242/jeb.234344] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Accepted: 03/17/2021] [Indexed: 12/29/2022]
Abstract
The brainstem region medullary raphe modulates non-shivering and shivering thermogenesis and cutaneous vasomotion in rodents. Whether the same scenario occurs in the other endothermic group, i.e. birds, is still unknown. Therefore, we hypothesised that the medullary raphe modulates heat gain and loss thermoeffectors in birds. We investigated the effect of glutamatergic and GABAergic inhibitions in this specific region on body temperature (Tb), oxygen consumption (thermogenesis), ventilation (O2 supply in cold, thermal tachypnea in heat) and heat loss index (cutaneous vasomotion) in one-week-old chicken exposed to neutral (31°C), cold (26°C) and heat (36°C) conditions. Intra-medullary raphe antagonism of NMDA glutamate (AP5; 0.5, 5 mM) and GABAA (bicuculline; 0.05, 0.5 mM) receptors reduced Tb of chicks at 31°C and 26oC, due mainly to an O2 consumption decrease. AP5 transiently increased breathing frequency during cold exposure. At 31°C, heat loss index was higher in the bicuculline and AP5 groups (higher doses) than vehicle at the beginning of the Tb reduction. No treatment affected any variable tested at 36oC. The results suggest that glutamatergic and GABAergic excitatory influences on the medullary raphe of chicks modulate thermogenesis and glutamatergic stimulation prevents tachypnea, without having any role in warmth-defence responses. A double excitation influence on the medullary raphe may provide a protective neural mechanism for supporting thermogenesis during early life, when energy expenditure to support growth and homeothermy is high. This novel demonstration of a thermoregulatory role for the raphe in birds suggests a convergent brainstem neurochemical regulation of body temperature in endotherms.
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Affiliation(s)
- Caroline Cristina-Silva
- Department of Animal Morphology and Physiology, College of Agricultural and Veterinary Sciences, São Paulo State University, Jaboticabal, SP, 14884-900, Brazil
- Joint UFSCar-UNESP Graduate Program of Physiological Sciences, Sao Carlos, SP, 13565-905, Brazil
| | - Luciane H Gargaglioni
- Department of Animal Morphology and Physiology, College of Agricultural and Veterinary Sciences, São Paulo State University, Jaboticabal, SP, 14884-900, Brazil
| | - Kênia Cardoso Bícego
- Department of Animal Morphology and Physiology, College of Agricultural and Veterinary Sciences, São Paulo State University, Jaboticabal, SP, 14884-900, Brazil
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Zhang Z, Park JW, Ahn IS, Diamante G, Sivakumar N, Arneson D, Yang X, van Veen JE, Correa SM. Estrogen receptor alpha in the brain mediates tamoxifen-induced changes in physiology in mice. eLife 2021; 10:63333. [PMID: 33647234 PMCID: PMC7924955 DOI: 10.7554/elife.63333] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Accepted: 01/25/2021] [Indexed: 12/24/2022] Open
Abstract
Adjuvant tamoxifen therapy improves survival in breast cancer patients. Unfortunately, long-term treatment comes with side effects that impact health and quality of life, including hot flashes, changes in bone density, and fatigue. Partly due to a lack of proven animal models, the tissues and cells that mediate these negative side effects are unclear. Here, we show that mice undergoing tamoxifen treatment experience changes in temperature, bone, and movement. Single-cell RNA sequencing reveals that tamoxifen treatment induces widespread gene expression changes in the hypothalamus and preoptic area (hypothalamus-POA). These expression changes are dependent on estrogen receptor alpha (ERα), as conditional knockout of ERα in the hypothalamus-POA ablates or reverses tamoxifen-induced gene expression. Accordingly, ERα-deficient mice do not exhibit tamoxifen-induced changes in temperature, bone, or movement. These findings provide mechanistic insight into the effects of tamoxifen on the hypothalamus-POA and indicate that ERα mediates several physiological effects of tamoxifen treatment in mice.
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Affiliation(s)
- Zhi Zhang
- Department of Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, United States.,Laboratory of Neuroendocrinology of the Brain Research Institute, University of California Los Angeles, Los Angeles, United States
| | - Jae Whan Park
- Department of Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, United States.,Laboratory of Neuroendocrinology of the Brain Research Institute, University of California Los Angeles, Los Angeles, United States
| | - In Sook Ahn
- Department of Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, United States
| | - Graciel Diamante
- Department of Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, United States
| | - Nilla Sivakumar
- Department of Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, United States.,Laboratory of Neuroendocrinology of the Brain Research Institute, University of California Los Angeles, Los Angeles, United States
| | - Douglas Arneson
- Department of Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, United States
| | - Xia Yang
- Department of Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, United States
| | - J Edward van Veen
- Department of Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, United States.,Laboratory of Neuroendocrinology of the Brain Research Institute, University of California Los Angeles, Los Angeles, United States
| | - Stephanie M Correa
- Department of Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, United States.,Laboratory of Neuroendocrinology of the Brain Research Institute, University of California Los Angeles, Los Angeles, United States
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Overview of the major classes of new psychoactive substances, psychoactive effects, analytical determination and conformational analysis of selected illegal drugs. OPEN CHEM 2021. [DOI: 10.1515/chem-2021-0196] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Abstract
The misuse of psychoactive substances is attracting a great deal of attention from the general public. An increase use of psychoactive substances is observed among young people who do not have enough awareness of the harmful effects of these substances. Easy access to illicit drugs at low cost and lack of effective means of routine screening for new psychoactive substances (NPS) have contributed to the rapid increase in their use. New research and evidence suggest that drug use can cause a variety of adverse psychological and physiological effects on human health (anxiety, panic, paranoia, psychosis, and seizures). We describe different classes of these NPS drugs with emphasis on the methods used to identify them and the identification of their metabolites in biological specimens. This is the first review that thoroughly gives the literature on both natural and synthetic illegal drugs with old known data and very hot new topics and investigations, which enables the researcher to use it as a starting point in the literature exploration and planning of the own research. For the first time, the conformational analysis was done for selected illegal drugs, giving rise to the search of the biologically active conformations both theoretically and using lab experiments.
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40
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Rheum rhaponticum Root Extract Improves Vasomotor Menopausal Symptoms and Estrogen-Regulated Targets in Ovariectomized Rat Model. Int J Mol Sci 2021; 22:ijms22031032. [PMID: 33494167 PMCID: PMC7864327 DOI: 10.3390/ijms22031032] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 01/14/2021] [Accepted: 01/14/2021] [Indexed: 11/16/2022] Open
Abstract
Ovarian insufficiency and ovariectomy are characterized by deregulated heat loss mechanisms. Unlike hormone therapy, ERr 731 (a standardized botanical extract of Siberian rhubarb Rheum rhaponticum L. high in rhaponticin) acts like a selective estrogen receptor modulator for ERβ receptors and may offer a higher degree of safety while maintaining the desired efficacy profile. In this study, we examined the relationship between oral administration of ERr 731 and the underlying components of skin vasomotion responses in an ovariectomized (OVX) rat model. ERr 731 dose-dependently reduced tail skin temperature (Tskin) values by an average of 1 °C. The rapid onset of this effect was observed in 1 and 3 mg/kg/day ERr 731 groups as early as day 2 of administration, and remained in place for the duration of the treatment (2 weeks). Substituting ERr 731 after E2 withdrawal helped maintain body temperature similarly to E2 alone, suggesting the usefulness of ERr 731 for replacing existing hormonal therapy in humans. ERr 731 also acted as a highly selective agonist for ERβ in the hypothalamus of OVX rats, as well as in ERα/β cell-based reporter assays. These data validate the OVX/Tskin rat model as a suitable screening platform to evaluate botanical and pharmaceutical treatments of menopause, while providing further evidence for the efficacy of ERr 731 towards alleviating vasomotor menopausal symptoms and improving wellbeing during the menopausal transition.
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Telci EA, Aslan UB, Yagci N, Cavlak U, Kabul EG, Kara G, Kose T, Yarar F, Karahan S, Atalay OT. The Turkish version of the Neck Bournemouth Questionnaire in patients with chronic neck pain: a cultural adaptation, reliability, and validity study. Arch Med Sci 2021; 17:708-713. [PMID: 34025841 PMCID: PMC8130469 DOI: 10.5114/aoms.2019.89322] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Accepted: 03/28/2018] [Indexed: 11/17/2022] Open
Abstract
INTRODUCTION The cultural adaptation of a self-report measurement in different languages is important for developing common strategies for evaluation and treatment. The Neck Bournemouth Questionnaire (NBQ), which was developed to evaluate patients with neck pain, was adapted from the Bournemouth Questionnaire in accordance with the International Classification of Functioning, Disability and Health (ICF) categories. The aim of this study was to conduct the Turkish cultural adaptation, validity and reliability study of the NBQ. MATERIAL AND METHODS The study included 119 patients (93 females, 26 males; mean age: 37.2 ±11.8 years) with chronic nonspecific neck pain. The NBQ, Neck Disability Index (NDI) and Nottingham Health Profile (NHP) questionnaires were administered to all the subjects. Test-retest reliability (intraclass correlation coefficient) and the internal consistency (Cronbach's α) were the methods used for the reliability study. The relationship between NBQ, NDI and NHP was investigated for concurrent validity. Exploratory and confirmatory factor analysis was used for construct validity. RESULTS The Neck Bournemouth Questionnaire showed good internal consistency (α = 0.87). The test-retest reliability coefficient was 0.913 (95% CI: 0.875-0.940). The correlations between NBQ and NDI and NHP were significant (p < 0.05). The questionnaire was found to have one factor and the explained variance was 59.084% as a result of factor analysis. CONCLUSIONS The Neck Bournemouth Questionnaire is a valid and reliable scale for patients with chronic neck pain in the Turkish population.
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Affiliation(s)
| | | | - Nesrin Yagci
- School of Physical Therapy, Pamukkale University, Denizli, Turkey
| | - Ugur Cavlak
- Department of Physiotherapy and Rehabilitation, Avrasya University, Trabzon, Turkey
| | - Elif Gur Kabul
- School of Physical Therapy, Pamukkale University, Denizli, Turkey
| | - Guzin Kara
- School of Physical Therapy, Pamukkale University, Denizli, Turkey
| | | | - Feride Yarar
- School of Physical Therapy, Pamukkale University, Denizli, Turkey
| | - Sevilay Karahan
- Faculty of Medicine, Department of Biostatistics, Hacettepe University, Ankara, Turkey
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Zhang Z, Reis FMCV, He Y, Park JW, DiVittorio JR, Sivakumar N, van Veen JE, Maesta-Pereira S, Shum M, Nichols I, Massa MG, Anderson S, Paul K, Liesa M, Ajijola OA, Xu Y, Adhikari A, Correa SM. Estrogen-sensitive medial preoptic area neurons coordinate torpor in mice. Nat Commun 2020; 11:6378. [PMID: 33311503 PMCID: PMC7732979 DOI: 10.1038/s41467-020-20050-1] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 11/12/2020] [Indexed: 12/15/2022] Open
Abstract
Homeotherms maintain a stable internal body temperature despite changing environments. During energy deficiency, some species can cease to defend their body temperature and enter a hypothermic and hypometabolic state known as torpor. Recent advances have revealed the medial preoptic area (MPA) as a key site for the regulation of torpor in mice. The MPA is estrogen-sensitive and estrogens also have potent effects on both temperature and metabolism. Here, we demonstrate that estrogen-sensitive neurons in the MPA can coordinate hypothermia and hypometabolism in mice. Selectively activating estrogen-sensitive MPA neurons was sufficient to drive a coordinated depression of metabolic rate and body temperature similar to torpor, as measured by body temperature, physical activity, indirect calorimetry, heart rate, and brain activity. Inducing torpor with a prolonged fast revealed larger and more variable calcium transients from estrogen-sensitive MPA neurons during bouts of hypothermia. Finally, whereas selective ablation of estrogen-sensitive MPA neurons demonstrated that these neurons are required for the full expression of fasting-induced torpor in both female and male mice, their effects on thermoregulation and torpor bout initiation exhibit differences across sex. Together, these findings suggest a role for estrogen-sensitive MPA neurons in directing the thermoregulatory and metabolic responses to energy deficiency.
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Affiliation(s)
- Zhi Zhang
- Department of Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, CA, USA
- Brain Research Institute, University of California Los Angeles, Los Angeles, CA, USA
| | - Fernando M C V Reis
- Department of Psychology, University of California Los Angeles, Los Angeles, CA, USA
| | - Yanlin He
- USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA
- Pennington Biomedical Research Center, Louisiana State University, Baton Rouge, LA, USA
| | - Jae W Park
- Department of Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, CA, USA
| | - Johnathon R DiVittorio
- Department of Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, CA, USA
| | - Nilla Sivakumar
- Department of Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, CA, USA
| | - J Edward van Veen
- Department of Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, CA, USA
- Brain Research Institute, University of California Los Angeles, Los Angeles, CA, USA
| | - Sandra Maesta-Pereira
- Department of Psychology, University of California Los Angeles, Los Angeles, CA, USA
| | - Michael Shum
- Division of Endocrinology, Department of Medicine, David Geffen School of Medicine, Los Angeles, CA, USA
- Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, Los Angeles, CA, USA
| | - India Nichols
- Department of Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, CA, USA
| | - Megan G Massa
- Department of Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, CA, USA
- Brain Research Institute, University of California Los Angeles, Los Angeles, CA, USA
| | - Shawn Anderson
- Department of Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, CA, USA
| | - Ketema Paul
- Department of Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, CA, USA
| | - Marc Liesa
- Division of Endocrinology, Department of Medicine, David Geffen School of Medicine, Los Angeles, CA, USA
- Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, Los Angeles, CA, USA
| | - Olujimi A Ajijola
- UCLA Cardiac Arrhythmia Center, Department of Medicine, David Geffen School of Medicine, Los Angeles, CA, USA
| | - Yong Xu
- USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA
| | - Avishek Adhikari
- Brain Research Institute, University of California Los Angeles, Los Angeles, CA, USA
- Department of Psychology, University of California Los Angeles, Los Angeles, CA, USA
| | - Stephanie M Correa
- Department of Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, CA, USA.
- Brain Research Institute, University of California Los Angeles, Los Angeles, CA, USA.
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Mendes C, Gomes G, Belpiede LT, do Carmo Buonfiglio D, Motta-Teixeira LC, Amaral FG, Cipolla-Neto J. The effects of melatonin daily supplementation to aged rats on the ability to withstand cold, thermoregulation and body weight. Life Sci 2020; 265:118769. [PMID: 33309717 DOI: 10.1016/j.lfs.2020.118769] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 11/05/2020] [Accepted: 11/13/2020] [Indexed: 02/01/2023]
Abstract
AIMS Investigate the role of melatonin on the regulation of body temperature in aged animals that have impaired melatonin production. MATERIAL AND METHODS Aged Male Wistar rats were randomly assigned to the following groups: 1) control (vehicle added to the water bottles during the dark phase) and 2) melatonin-treated (10 mg/kg melatonin added to the water bottles during the dark phase). Before and after 16 weeks of vehicle or melatonin treatment, control group and melatonin-treated animals were acutely exposed to 18 °C for 2 h for an acute cold challenge and thermal images were obtained using an infrared camera. After 16 weeks, animals were euthanized and brown and beige adipocytes were collected for analysis of genes involved in the thermogenesis process by real-time PCR, and the uncoupling protein expression was evaluated by immunoblotting. Browning intensity of beige adipocytes were quantified by staining with hematoxylin-eosin. KEY FINDINGS Chronic melatonin supplementation induced a minor increase in body mass and increased the animal's thermogenic potential in the cold acute challenge. Brown and beige adipocytes acted in a coordinated and complementary way to ensure adequate heat production. SIGNIFICANCE Melatonin plays an important role in the thermoregulatory mechanisms, ensuring greater capacity to withstand cold and, also, participating in the regulation of energy balance.
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Affiliation(s)
- Caroline Mendes
- Neurobiology Lab, Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Guilherme Gomes
- Department of Physics and Interdisciplinary Science (FCI), São Carlos Institute of Physics (IFSC), University of São Paulo, São Paulo, Brazil
| | - Luciana Tocci Belpiede
- Neurobiology Lab, Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | | | - Lívia Clemente Motta-Teixeira
- Neurobiology Lab, Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil
| | - Fernanda Gaspar Amaral
- Pineal Neurobiology Lab, Department of Physiology, Federal University of São Paulo, São Paulo, SP, Brazil
| | - José Cipolla-Neto
- Neurobiology Lab, Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil.
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Combined stimuli of cold, hypoxia, and dehydration status on body temperature in rats: a pilot study with practical implications for humans. BMC Res Notes 2020; 13:530. [PMID: 33176867 PMCID: PMC7661168 DOI: 10.1186/s13104-020-05375-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Accepted: 11/05/2020] [Indexed: 01/23/2023] Open
Abstract
OBJECTIVE As human thermoregulatory responses to maintain core body temperature (Tcore) under multiple stressors such as cold, hypoxia, and dehydration (e.g., exposure to high-altitude) are varied, the combined effects of cold, hypoxia, and dehydration status on Tcore in rats were investigated. The following environmental conditions were constructed: (1) thermoneutral (24 °C) or cold (10 °C), (2) normoxia (21% O2) or hypoxia (12% O2), and (3) euhydration or dehydration (48 h water deprivation), resulted in eight environmental conditions [2 ambient temperatures (Ta) × 2 oxygen levels × 2 hydration statuses)]. Each condition lasted for 24 h. RESULTS Normoxic conditions irrespective of hypoxia or dehydration did not strongly decrease the area under the curve (AUC) in Tcore during the 24 period, whereas, hypoxic conditions caused greater decreases in the AUC in Tcore, which was accentuated with cold and dehydration (Ta × O2 × hydration, P = 0.040 by three-way ANOVA). In contrast, multiple stressors (Ta × O2 × hydration or Ta × O2 or O2 × hydration or Ta × hydration) did not affect locomotor activity counts (all P > 0.05), but a significant simple main effect for O2 and Ta was observed (P < 0.001). Heat loss index was not affected by all environmental conditions (all P > 0.05). In conclusion, decreases in Tcore were most affected by multiple environmental stressors such as cold, hypoxia, and dehydration.
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45
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Ruthenium red attenuates brown adipose tissue thermogenesis in rats. J Therm Biol 2020; 95:102779. [PMID: 33454027 DOI: 10.1016/j.jtherbio.2020.102779] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 11/04/2020] [Accepted: 11/06/2020] [Indexed: 11/21/2022]
Abstract
Ruthenium red (RR) is a non-selective antagonist of the temperature-sensitive Transient Receptor Potential (TRP) channels and it is an important pharmacological tool in thermoregulatory research. However, the effect of RR on thermoeffector activity is not well established. Here we evaluated the effect of RR on cold-defense thermoeffectors induced by menthol, an agonist of the cold-sensitive TRPM8 channel. Adult male Wistar rats were used. Epidermal treatment with menthol raised deep body temperature due to an increase in oxygen consumption (an index of thermogenesis), a reduction in heat loss index (an index of cutaneous vasoconstriction), and an induction in warmth-seeking behavior in a two-temperature choice apparatus. Pretreatment with RR attenuated the menthol-induced increase in deep body temperature and oxygen consumption, but it did not affect heat loss index and warmth-seeking behavior. To stimulate brown adipose tissue thermogenesis, rats were treated with CL 316,243, a potent and selective β3-adrenoceptor agonist. CL 316,243 increased deep body temperature, which was attenuated by RR pretreatment. We conclude that RR reduces brown adipose tissue thermogenesis induced by menthol and CL 316,243, independent of effects at the thermal sensor level (i.e., TRPM8).
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46
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Drummond LR, Campos HO, de Andrade Lima PM, da Fonseca CG, Kunstetter AC, Rodrigues QT, Szawka RE, Natali AJ, Prímola-Gomes TN, Wanner SP, Coimbra CC. Impaired thermoregulation in spontaneously hypertensive rats during physical exercise is related to reduced hypothalamic neuronal activation. Pflugers Arch 2020; 472:1757-1768. [PMID: 33040159 DOI: 10.1007/s00424-020-02474-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 09/05/2020] [Accepted: 10/06/2020] [Indexed: 12/25/2022]
Abstract
This study aimed to evaluate the physical exercise-induced neuronal activation in brain nuclei controlling thermoregulatory responses in hypertensive and normotensive rats. Sixteen-week-old male normotensive Wistar rats (NWRs) and spontaneously hypertensive rats (SHRs) were implanted with an abdominal temperature sensor. After recovery, the animals were subjected to a constant-speed treadmill running (at 60% of the maximum aerobic speed) for 30 min at 25 °C. Core (Tcore) and tail-skin (Tskin) temperatures were measured every minute during exercise. Ninety minutes after the exercise, the rats were euthanized, and their brains were collected to determine the c-Fos protein expression in the following areas that modulate thermoregulatory responses: medial preoptic area (mPOA), paraventricular hypothalamic nucleus (PVN), and supraoptic nucleus (SON). During treadmill running, the SHR group exhibited a greater increase in Tcore and an augmented threshold for cutaneous heat loss relative to the NWR group. In addition, the SHRs showed reduced neuronal activation in the mPOA (< 49.7%) and PVN (< 44.2%), but not in the SON. The lower exercise-induced activation in the mPOA and PVN in hypertensive rats was strongly related to the delayed onset of cutaneous heat loss. We conclude that the enhanced exercise-induced hyperthermia in hypertensive rats can be partially explained by a delayed cutaneous heat loss, which is, in turn, associated with reduced activation of brain areas modulating thermoregulatory responses.
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Affiliation(s)
- Lucas Rios Drummond
- Laboratório de Endocrinologia e Metabolismo, Departamento de Fisiologia e Biofísica, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627., Belo Horizonte, MG, 31270-901, Brazil.
| | - Helton Oliveira Campos
- Laboratório de Endocrinologia e Metabolismo, Departamento de Fisiologia e Biofísica, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627., Belo Horizonte, MG, 31270-901, Brazil
| | - Paulo Marcelo de Andrade Lima
- Laboratório de Endocrinologia e Metabolismo, Departamento de Fisiologia e Biofísica, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627., Belo Horizonte, MG, 31270-901, Brazil
| | - Cletiana Gonçalves da Fonseca
- Laboratório de Fisiologia do Exercício, Departamento de Educação Física, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Ana Cançado Kunstetter
- Laboratório de Fisiologia do Exercício, Departamento de Educação Física, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Quezia Teixeira Rodrigues
- Laboratório de Endocrinologia e Metabolismo, Departamento de Fisiologia e Biofísica, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627., Belo Horizonte, MG, 31270-901, Brazil
| | - Raphael Escorsim Szawka
- Laboratório de Endocrinologia e Metabolismo, Departamento de Fisiologia e Biofísica, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627., Belo Horizonte, MG, 31270-901, Brazil
| | - Antônio José Natali
- Laboratório de Biologia do Exercício, Departamento de Educação Física, Universidade Federal de Viçosa, Viçosa, MG, Brazil
| | - Thales Nicolau Prímola-Gomes
- Laboratório de Biologia do Exercício, Departamento de Educação Física, Universidade Federal de Viçosa, Viçosa, MG, Brazil
| | - Samuel Penna Wanner
- Laboratório de Fisiologia do Exercício, Departamento de Educação Física, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Cândido Celso Coimbra
- Laboratório de Endocrinologia e Metabolismo, Departamento de Fisiologia e Biofísica, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627., Belo Horizonte, MG, 31270-901, Brazil
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47
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Lomax TM, Ashraf S, Yilmaz G, Harmancey R. Loss of Uncoupling Protein 3 Attenuates Western Diet-Induced Obesity, Systemic Inflammation, and Insulin Resistance in Rats. Obesity (Silver Spring) 2020; 28:1687-1697. [PMID: 32716607 PMCID: PMC7483834 DOI: 10.1002/oby.22879] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Revised: 04/09/2020] [Accepted: 04/29/2020] [Indexed: 12/29/2022]
Abstract
OBJECTIVE Uncoupling protein 3 (UCP3) is a mitochondrial carrier related to fatty acid metabolism. Although gene variants of UCP3 are associated with human obesity, their contribution to increased adiposity remains unclear. This study investigated the impact that loss of UCP3 has on diet-induced obesity in rats. METHODS Male UCP3 knockout rats (ucp3-/- ) and wild-type littermates (ucp3+/+ ) were fed a high-fat, high-carbohydrate Western diet for 21 weeks. Body composition was analyzed by EchoMRI. Whole-body insulin sensitivity and rates of tissue glucose uptake were determined by using hyperinsulinemic-euglycemic clamp. Changes in tissue physiology were interrogated by microscopy and RNA sequencing. RESULTS Loss of UCP3 decreased fat mass gain, white adipocytes size, and systemic inflammation. The ucp3-/- rats also exhibited preserved insulin sensitivity and increased glucose uptake in interscapular brown adipose tissue (iBAT). Brown adipocytes from ucp3-/- rats were protected from cellular degeneration caused by lipid accumulation and from reactive oxygen species-induced protein sulfonation. Increased glutathione levels in iBAT from ucp3-/- rats were linked to upregulation of genes encoding enzymes from the transsulfuration pathway in that tissue. CONCLUSIONS Loss of UCP3 partially protects rats from diet-induced obesity. This phenotype is related to induction of a compensatory antioxidant mechanism and prevention of iBAT whitening.
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Affiliation(s)
- Tyler M. Lomax
- Department of Physiology and Biophysics, University of Mississippi Medical Center, Jackson, MS, USA
- Mississippi Center for Obesity Research, University of Mississippi Medical Center, Jackson, MS, USA
- Mississippi Center for Heart Research, University of Mississippi Medical Center, Jackson, MS, USA
| | - Sadia Ashraf
- Department of Physiology and Biophysics, University of Mississippi Medical Center, Jackson, MS, USA
- Mississippi Center for Obesity Research, University of Mississippi Medical Center, Jackson, MS, USA
- Mississippi Center for Heart Research, University of Mississippi Medical Center, Jackson, MS, USA
| | - Gizem Yilmaz
- Department of Physiology and Biophysics, University of Mississippi Medical Center, Jackson, MS, USA
- Mississippi Center for Obesity Research, University of Mississippi Medical Center, Jackson, MS, USA
- Mississippi Center for Heart Research, University of Mississippi Medical Center, Jackson, MS, USA
| | - Romain Harmancey
- Department of Physiology and Biophysics, University of Mississippi Medical Center, Jackson, MS, USA
- Mississippi Center for Obesity Research, University of Mississippi Medical Center, Jackson, MS, USA
- Mississippi Center for Heart Research, University of Mississippi Medical Center, Jackson, MS, USA
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48
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Amano Y, Nonaka Y, Takeda R, Kano Y, Hoshino D. Effects of electrical stimulation-induced resistance exercise training on white and brown adipose tissues and plasma meteorin-like concentration in rats. Physiol Rep 2020; 8:e14540. [PMID: 32812347 PMCID: PMC7435032 DOI: 10.14814/phy2.14540] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 07/16/2020] [Accepted: 07/20/2020] [Indexed: 12/26/2022] Open
Abstract
Chronic endurance exercise training induces morphological and metabolic alterations including mitochondrial biogenesis in white adipose tissue (WAT) and brown adipose tissue (BAT) in rodents. A myokine called meteorin-like (Metrnl) is associated with morphological and metabolic adaptation and increased in blood after acute resistance exercise. However, the effects of chronic resistance exercise training (RT), which aims to increase muscle mass and strength, on WAT and BAT are unclear. Therefore, we aimed to clarify the effects of RT on morphological and metabolic parameters in WAT and BAT and on plasma Metrnl concentrations. We applied electrical stimulation to both legs of rats as RT three times a week for 4 weeks. RT reduced adipocyte size in subcutaneous WAT but induced no changes in mitochondrial and thermogenesis proteins. In BAT, peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α) protein levels and mitochondrial content markers were significantly higher in the RT group compared with the control group. A significant positive correlation was found between the expression of PGC-1α in BAT and plasma Metrnl concentrations. These results suggest that plasma Metrnl is associated with PGC-1α and mitochondrial biogenesis in BAT. This study describes a potential role of RT in preventing metabolic diseases via altering WAT and BAT and increasing plasma Mertnl concentrations.
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Affiliation(s)
- Yuhei Amano
- Bioscience and Technology ProgramDepartment of Engineering ScienceThe University of Electro‐CommunicationsChofuJapan
| | - Yudai Nonaka
- Bioscience and Technology ProgramDepartment of Engineering ScienceThe University of Electro‐CommunicationsChofuJapan
- Japan Society for the Promotion of Science (JSPS)TokyoJapan
| | - Reo Takeda
- Bioscience and Technology ProgramDepartment of Engineering ScienceThe University of Electro‐CommunicationsChofuJapan
| | - Yutaka Kano
- Bioscience and Technology ProgramDepartment of Engineering ScienceThe University of Electro‐CommunicationsChofuJapan
| | - Daisuke Hoshino
- Bioscience and Technology ProgramDepartment of Engineering ScienceThe University of Electro‐CommunicationsChofuJapan
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49
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Škop V, Liu N, Guo J, Gavrilova O, Reitman ML. The contribution of the mouse tail to thermoregulation is modest. Am J Physiol Endocrinol Metab 2020; 319:E438-E446. [PMID: 32691633 PMCID: PMC7473913 DOI: 10.1152/ajpendo.00133.2020] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Understanding mouse thermal physiology informs the usefulness of mice as models of human disease. It is widely assumed that the mouse tail contributes greatly to heat loss (as it does in rat), but this has not been quantitated. We studied C57BL/6J mice after tail amputation. Tailless mice housed at 22°C did not differ from littermate controls in body weight, lean or fat content, or energy expenditure. With acute changes in ambient temperature from 19 to 39°C, tailless and control mice demonstrated similar body temperatures (Tb), metabolic rates, and heat conductances and no difference in thermoneutral point. Treatment with prazosin, an α1-adrenergic antagonist and vasodilator, increased tail temperature in control mice by up to 4.8 ± 0.8°C. Comparing prazosin treatment in tailless and control mice suggested that the tail's contribution to total heat loss was a nonsignificant 3.4%. Major heat stress produced by treatment at 30°C with CL316243, a β3-adrenergic agonist, increased metabolic rate and Tb and, at a matched increase in metabolic rate, the tailless mice showed a 0.72 ± 0.14°C greater Tb increase and 7.6% lower whole body heat conductance. Thus, the mouse tail is a useful biomarker of vasodilation and thermoregulation, but in our experiments contributes only 5-8% of whole body heat dissipation, less than the 17% reported for rat. Heat dissipation through the tail is important under extreme scenarios such as pharmacological activation of brown adipose tissue; however, non-tail contributions to heat loss may have been underestimated in the mouse.
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Affiliation(s)
- Vojtěch Škop
- Diabetes, Endocrinology, and Obesity Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland
| | - Naili Liu
- Mouse Metabolism Core, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland
| | - Juen Guo
- Laboratory of Biological Modeling, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland
| | - Oksana Gavrilova
- Mouse Metabolism Core, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland
| | - Marc L Reitman
- Diabetes, Endocrinology, and Obesity Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland
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50
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Škop V, Guo J, Liu N, Xiao C, Hall KD, Gavrilova O, Reitman ML. Mouse Thermoregulation: Introducing the Concept of the Thermoneutral Point. Cell Rep 2020; 31:107501. [PMID: 32294435 PMCID: PMC7243168 DOI: 10.1016/j.celrep.2020.03.065] [Citation(s) in RCA: 85] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 11/18/2019] [Accepted: 03/19/2020] [Indexed: 12/21/2022] Open
Abstract
Human and mouse thermal physiology differ due to dissimilar body sizes. Unexpectedly, in mice we found no ambient temperature zone where both metabolic rate and body temperature were constant. Body temperature began increasing once cold-induced thermogenesis was no longer required. This result reproduced in male, female, C57BL/6J, 129, chow-fed, diet-induced obese, and ob/ob mice as well as Trpv1-/-;Trpm8-/-;Trpa1-/- mice lacking thermal sensory channels. During the resting-light phase, the energy expenditure minimum spanned ∼4°C of ambient temperature, whereas in the active-dark phase it approximated a point. We propose the concept of a thermoneutral point (TNP), a discrete ambient temperature below which energy expenditure increases and above which body temperature increases. Humans do not have a TNP. As studied, the mouse TNP is ∼29°C in light phase and ∼33°C in dark phase. These observations inform how thermoneutrality is defined and how mice are used to model human energy physiology and drug development.
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Affiliation(s)
- Vojtěch Škop
- Diabetes, Endocrinology, and Obesity Branch, National Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda, MD 20892, USA
| | - Juen Guo
- Laboratory of Biological Modeling, National Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda, MD 20892, USA
| | - Naili Liu
- Mouse Metabolism Core, National Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda, MD 20892, USA
| | - Cuiying Xiao
- Diabetes, Endocrinology, and Obesity Branch, National Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda, MD 20892, USA
| | - Kevin D Hall
- Laboratory of Biological Modeling, National Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda, MD 20892, USA
| | - Oksana Gavrilova
- Mouse Metabolism Core, National Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda, MD 20892, USA
| | - Marc L Reitman
- Diabetes, Endocrinology, and Obesity Branch, National Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda, MD 20892, USA.
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