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Wang L, Deng Z, Zhao Y, Yuan R, Yang M, Zhang Y, Li Y, Liu Y, Zhou F, Kang H. Mesenchymal stem cells regulate activation of microglia cells to improve hippocampal injury of heat stroke rats. J Therm Biol 2021; 101:103081. [PMID: 34879909 DOI: 10.1016/j.jtherbio.2021.103081] [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: 05/12/2021] [Revised: 08/05/2021] [Accepted: 08/12/2021] [Indexed: 10/20/2022]
Abstract
Heat stroke is a severe systemic inflammatory response disease caused by high fever, mainly with nervous system damage. Mesenchymal stem cells (MSCs) are currently believed to have anti-inflammation and immunomodulatory effects. Therefore, we aimed to explore the protective effect and mechanism of MSCs on heat stroke-induced excessive inflammation and neurological dysfunction. We established a heat stroke model in rats under conditions of continuous high temperature and high humidity. After modeling, rats were randomly divided into heat stroke model group, MSCs treatment group and normal temperature control group without any treatment. We performed survival analysis, neurological deficit score, histological staining of hippocampus and cerebellum, immunofluorescence staining of microglia, detection of inflammatory and chemokine levels in the hippocampus and cerebellum in each group. We found that MSCs treatment not only significantly reduced early (day 3) and late (day 28) mortality, but also prominently reduced nerve injury in heat stroke rats, and improved pathology and neuronal cell damage in the hippocampus and cerebellum. In addition, MSCs treatment can significantly inhibit the over-activation of hippocampal microglia in heat stroke rats and the levels of pro-inflammatory factors and chemokines in the hippocampus. Early treatment of MSCs can greatly promote the activation of cerebellar microglia in heat stroke rats. Meanwhile, MSCs treatment has an inhibitory effect on the level of chemokine in the cerebellum of rats in the early stage of heat stroke. In conclusion, the application of MSCs in the treatment of heat stroke in rats can significantly reduce mortality and neurological deficits and improve hippocampal damage, possibly by inhibiting the excessive activation of hippocampal microglia in heat stroke rats.
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Affiliation(s)
- Lu Wang
- Medical School of Chinese PLA, Beijing, China; Department of Critical Care Medicine, The First Medical Center, Chinese PLA General Hospital, Beijing, China.
| | - Zihui Deng
- Department of Biochemistry, Graduate School, Chinese PLA General Hospital, Beijing, China.
| | - Yan Zhao
- Department of Critical Care Medicine, The First Medical Center, Chinese PLA General Hospital, Beijing, China.
| | - Rui Yuan
- Medical School of Chinese PLA, Beijing, China; Department of Critical Care Medicine, The First Medical Center, Chinese PLA General Hospital, Beijing, China.
| | - Mengmeng Yang
- Department of Critical Care Medicine, The First Medical Center, Chinese PLA General Hospital, Beijing, China.
| | - Yu Zhang
- Department of Critical Care Medicine, The First Medical Center, Chinese PLA General Hospital, Beijing, China.
| | - Yun Li
- Medical School of Chinese PLA, Beijing, China; Department of Critical Care Medicine, The First Medical Center, Chinese PLA General Hospital, Beijing, China.
| | - Yuyan Liu
- Medical School of Chinese PLA, Beijing, China; Department of Critical Care Medicine, The First Medical Center, Chinese PLA General Hospital, Beijing, China.
| | - Feihu Zhou
- Department of Critical Care Medicine, The First Medical Center, Chinese PLA General Hospital, Beijing, China.
| | - Hongjun Kang
- Department of Critical Care Medicine, The First Medical Center, Chinese PLA General Hospital, Beijing, China.
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Tai PA, Chang CK, Niu KC, Lin MT, Chiu WT, Lin JW. Attenuation of Heat-Induced Hypothalamic Ischemia, Inflammation, and Damage by Hyperbaric Oxygen in Rats. J Neurotrauma 2021; 38:1185-1192. [PMID: 20578826 DOI: 10.1089/neu.2010.1323] [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] [Indexed: 11/13/2022] Open
Abstract
The present study was attempted to assess the mechanisms underlying the beneficial effects of hyperbaric oxygen (HBO2; 100% O2 at 253 kpa) in treating experimental heatstroke. Anesthetized rats were divided into five major groups: normothermic control (NC) rats treated with normobaric air (NBA; 21% O2 at 101 kpa; NC + NBA); NC rats treated with HBO2 (NC + HBO2); heatstroke (HS) rats treated with NBA (HS + NBA); HS rats treated with hyperbaric air (HBA; 21% at 253 kpa; HS + HBA); and HS rats treated with HBO2 (HS + HBO2). HS groups were exposed to heat (43°C) for exactly 68 min and then allowed to recover at 26°C. HBA or HBO2 was adopted 68 or 78 min after the start of heat exposure. Survival time values for (HS + NBA) rats, (HS + HBA) rats at 68 min, (HS + HBA) rats at 78 min, (HS + HBO2) rats at 68 min, and (HS + HBO2) rats at 78 min were found to be 90 ± 3, 133 ± 12, 109 ± 9, 240 ± 18, and 170 ± 15 min, respectively. Resuscitation with HBA or HBO2 at 68 min was superior to those treated at 78 min in prolonging the survival time values. All (HS + NBA) animals displayed hyperthermia, hypotension, and increased cellular levels of ischemia, oxidative stress and damage markers, pro-inflammatory cytokines, and an indicator of polymorphonuclear cell accumulation in their hypothalamus as compared to those of NCs. Heat-induced hyperthermia was not affected by HBA or HBO2 treatment. However, heat-induced hypotension and hypothalamic ischemia, oxidative stress, neuronal damage, and inflammation were all significantly reduced by HBA or HBO2 therapy. Compared to those of HBA therapy, HBO2 therapy had a significantly higher beneficial effect in treating heatstroke. Our results suggested that HBO2 improved heatstroke outcomes, in part, by restoring normal hypothalamic function. Delaying the onset of HBO2 therapy reduced the therapeutic efficiency.
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Affiliation(s)
- Po-An Tai
- Graduate Institute of Clinical Medicine, Shuang Ho Hospital, Taipei Medical University, Taipei, Taiwan.,Department of Surgery, Buddhist Tzu Chi General Hospital, Taipei, Taiwan
| | - Chen-Kuei Chang
- Graduate Institute of Disease Prevention and Control, Shuang Ho Hospital, Taipei Medical University, Taipei, Taiwan.,Department of Neurosurgery, Mackay Memorial Hospital, Taipei, Taiwan
| | - Ko-Chi Niu
- Department of Medical Research, Chi Mei Medical Center, Tainan, Taiwan
| | - Mao-Tsun Lin
- Graduate Institute of Disease Prevention and Control, Shuang Ho Hospital, Taipei Medical University, Taipei, Taiwan.,Department of Medical Research, Chi Mei Medical Center, Tainan, Taiwan
| | - Wen-Ta Chiu
- Graduate Institute of Disease Prevention and Control, Shuang Ho Hospital, Taipei Medical University, Taipei, Taiwan
| | - Jia-Wei Lin
- Graduate Institute of Clinical Medicine, Shuang Ho Hospital, Taipei Medical University, Taipei, Taiwan.,Department of Neurosurgery, Shuang Ho Hospital, Taipei Medical University, Taipei, Taiwan
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Zhang T, Hu H, Tao Z, Niu B, Jiao S, Zhang J, Li Y, Cao B. A novel method for primary neuronal culture and characterization under different high temperature. In Vitro Cell Dev Biol Anim 2016; 52:823-8. [PMID: 27130681 DOI: 10.1007/s11626-016-0047-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 04/18/2016] [Indexed: 01/16/2023]
Abstract
Heatstroke is a big threat to human health; however, the characteristic of pathological changes of neurons during heatstroke development remains unclear. Here, using an in vitro model of primary cultured neurons from newborn Wistar rats, we investigated the effects of the different combinations of high temperature (37, 39, 41, 43, 45, and 47°C) and exposure time (45 min and 1 h) on the neurons. We found that, under the treatment of 45 min-heat, the neurons could resist high temperature up to 45°C, and under the treatment of 1 h-heat, the mortality of neurons increased as the temperature rises. After heating for 1 h, only a small minority of the neurons died under 41 and 43°C, which primarily occurred in the form of apoptosis. Up to 45°C for 1 h, most neurons occurred to necrosis. Meaningfully, some necrotic neurons expressed specific fried egg-like morphology. Our findings suggest that different high temperatures and exposure times were two key factors influencing the death of neurons. Under the high temperature (below 43°C for 1 h) similar to heatstroke, it just led a small percentage of neurons to apoptosis, and anti-apoptosis controls for preventing and treating heatstroke are promising.
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Affiliation(s)
- Tao Zhang
- Department of Neurology, Graduate School of the Second Military Medical University, Shanghai, China.,Department of Neurology, General Hospital of Jinan Military Command of PLA, 25 Shifan Road, Jinan, 250031, China.,Department of Neurology, The 303th Hospital of People's Liberation Army, Nanning, China
| | - Huaiqiang Hu
- Department of Neurology, General Hospital of Jinan Military Command of PLA, 25 Shifan Road, Jinan, 250031, China
| | - Zhen Tao
- Department of Neurology, General Hospital of Jinan Military Command of PLA, 25 Shifan Road, Jinan, 250031, China
| | - Bing Niu
- Department of Neurology, General Hospital of Jinan Military Command of PLA, 25 Shifan Road, Jinan, 250031, China
| | - Shusheng Jiao
- Department of Neurology, Bethune International Peace Hospital of the Chinese PLA, Shijiazhuang, China
| | - Jun Zhang
- Department of Burn and Plastic Surgery, The 205th Hospital of People's Liberation Army, Jinzhou, China
| | - Yiyang Li
- Department of Cardiology, The National Hospital of Guangxi Province, Nanning, China
| | - Bingzhen Cao
- Department of Neurology, General Hospital of Jinan Military Command of PLA, 25 Shifan Road, Jinan, 250031, China.
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Inoue Y, Hayashi Y, Kangawa K, Suzuki Y, Murakami N, Nakahara K. Des-acyl ghrelin prevents heatstroke-like symptoms in rats exposed to high temperature and high humidity. Neurosci Lett 2016; 615:28-32. [PMID: 26773867 DOI: 10.1016/j.neulet.2016.01.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Revised: 12/24/2015] [Accepted: 01/05/2016] [Indexed: 10/22/2022]
Abstract
We have shown previously that des-acyl ghrelin decreases body temperature in rats through activation of the parasympathetic nervous system. Here we investigated whether des-acyl ghrelin ameliorates heatstroke in rats exposed to high temperature. Peripheral administration of des-acyl ghrelin significantly attenuated hyperthermia induced by exposure to high-temperature (35°C) together with high humidity (70-80%). Although biochemical analysis revealed that exposure to high temperature significantly increased hematocrit and the serum levels of aspartate amino transferase (AST), alanine transaminase (ALT), blood urea nitrogen (BUN), creatinine and electrolytes (Na(+), K(+), Cl(-)), most of these heatstroke-associated reactions were significantly reduced by treatment with des-acyl ghrelin. The level of des-acyl ghrelin in plasma was also found to be significantly increased under high-temperature conditions. These results suggest that des-acyl ghrelin could be useful for preventing heatstroke under high temperature condition.
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Affiliation(s)
- Yoshiyuki Inoue
- Department of Veterinary Physiology, Faculty of Agriculture, University of Miyazaki, Miyazaki 889-2192, Japan
| | - Yujiro Hayashi
- Asubio Pharma Co., Ltd., 6-4-3 Minatojima-Minamimachi, Chuo-ku, Kobe 650-0047, Japan
| | - Kenji Kangawa
- Department of Biochemistry, National Cardiovascular Center Research Institute, 5-7-1 Fujishirodai, Suita, Osaka 565-8565, Japan
| | - Yoshihiro Suzuki
- Laboratory of Animal Health Science, School of Veterinary Medicine, Kitasato University, Aomori 034-8628, Japan
| | - Noboru Murakami
- Department of Veterinary Physiology, Faculty of Agriculture, University of Miyazaki, Miyazaki 889-2192, Japan
| | - Keiko Nakahara
- Department of Veterinary Physiology, Faculty of Agriculture, University of Miyazaki, Miyazaki 889-2192, Japan.
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5
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Chao CM, Cheng BC, Chen CY, Lin MT, Chang CP, Yang ST. Proteomic analysis of hypothalamic injury in heatstroke rats. Proteomics 2015; 15:1921-34. [PMID: 25663389 DOI: 10.1002/pmic.201400492] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2014] [Revised: 12/24/2014] [Accepted: 02/04/2015] [Indexed: 01/15/2023]
Abstract
Ischemic and oxidative damage to the hypothalamus may be associated with decreased heat tolerance as well as heatstroke formation. The present study explores the hypothalamic proteome mechanisms associated with heatstroke-mediated hypothalamic ischemia, and oxidative damage. Heatstroke rats had hypotension, hypothalamic ischemia, and lethality. In addition, they had hyperthermia and hypothalamic blood-brain-barrier disruption, oxidative stress, activated inflammation, and neuronal apoptosis and degeneration. 2DE combined LC-MS/MS revealed that heatstroke-induced ischemic injury and apoptosis were associated with upregulation of L-lactate dehydrogenase but downregulation of both dihydropyriminase-related protein and 14-3-3 Zeta isoform protein. Heat-induced blood-brain-barrier disruption might be related to upregulation of glial fibrillary acidic protein. Oxidative stress caused by heatstroke might be related to upregulation of cytosolic dehydrogenase-1. Also, heat-induced overproduction of proinflammatory cytokines might be associated with downregulation of stathmin 1. Heat-induced hypothalamic ischemia, apoptosis, injury (or upregulation of L-lactate dehydrogenase), blood-brain-barrier disruption (or upregulation of glial fibrillary acidic protein), oxidative stress (or upregulation of cytosolic dehydrogenase-1), and activated inflammation (or downregulation of stathmin 1) were all significantly reversed by whole body cooling. Our data indicate that cooling therapy improves outcomes of heatstroke by modulating hypothalamic proteome mechanisms.
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Affiliation(s)
- Chien-Ming Chao
- Department of Surgery and Department of Intensive Care Medicine, Chi Mei Medical Center, Tainan, Taiwan
| | - Bor-Chih Cheng
- Department of Surgery, Chi Mei Medical Center, Tainan, Taiwan.,Department of Biotechnology, Southern Taiwan University of Science and Technology, Tainan, Taiwan
| | - Chia-Ying Chen
- Department of Biotechnology, Southern Taiwan University of Science and Technology, Tainan, Taiwan
| | - Mao-Tsun Lin
- Department of Medical Research, Chi Mei Medical Center, Tainan, Taiwan
| | - Ching-Ping Chang
- Department of Biotechnology, Southern Taiwan University of Science and Technology, Tainan, Taiwan.,The Ph.D. Program for Neural Regenerative Medicine, Taipei Medical University, Taipei, Taiwan
| | - Shun-Tai Yang
- Department of Neurosurgery, Taipei Medical University-Shuang Ho Hospital, New Taipei City, Taiwan.,Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.,Department of Surgery, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan
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6
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Tu WZ, Cheng RD, Hu J, Wang JZ, Lin HY, Zou EM, Wang WS, Lou XF, Jiang SH. Combination treatment with Gua Sha and Blood-letting causes attenuation of systemic inflammation, activated coagulation, tissue ischemia and injury during heatstroke in rats. Chin J Integr Med 2014; 21:610-7. [PMID: 25098257 DOI: 10.1007/s11655-014-1816-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2012] [Indexed: 11/30/2022]
Abstract
OBJECTIVE Gua Sha and Blood-letting at the acupoints were Chinese traditional therapies for heatstroke. The purpose of present study was to assess the therapeutic effect of Gua Sha on the DU Meridian and Bladder Meridian combined with Blood-letting acupoints at Shixuan (EX-UE 11) and Weizhong (BL 40) on heatstroke. METHODS Anesthetized rats, immediately after the onset of heatstroke, were divided into four major groups: Gua Sha group, Blood-letting group, Gua Sha combined with Blood-letting group and model group. They were exposed to ambient temperature of 43 °C to induce heatstroke. Another group of rats were exposed to room temperature (26 °C) and used as normal control group. Their survival times were measured. In addition, their physiological and biochemical parameters were continuously monitored. RESULTS When rats underwent heatstroke, their survival time values were found to be 21-25 min. Treatment of Gua Sha combined with Bloodletting greatly improved the survival time (230±22 min) during heatstroke. All heatstoke animals displayed and activated coagulation evidenced by increased prothrombin time (PT), activated partial thromboplastin time (aPTT), D-dimer, and decreased platelet count, protein C. Furthermore, the animals displayed systemic inflammation evidenced by increased the serum levels of cytokines interleukin-1ß (IL-1ß), tumor necrosis factor α (TNF-α) and malondialdehyde (MDA). Biochemical markers evidenced by cellular ischemia and injury/dysfunction included increased plasma levels of blood urea nitrogen (BUN), creatinine, serum glutamic oxaloacetic transaminase (SGOT), serum glutamic pyruvic transaminase (SGPT), and alkaline phosphatase (ALP) were all elevated during heatstroke. Core temperatures (Tco) were also increased during heatstroke. In contrast, the values of mean arterial pressure were signifificantly lower during heatstroke. These heatstroke reactions were all signifificantly suppressed by treatment of Gua Sha and Blood-letting, especially the combination therapy. CONCLUSION Gua Sha combined with Blood-letting after heatstroke may improve survival by ameliorating systemic inflflammation, hypercoagulable state, and tissue ischemia and injury in multiple organs.
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Affiliation(s)
- Wen-zhan Tu
- Department of Physical Medicine and Rehabilitation, the Second Affiliated Hospital of Wenzhou Medical College, Wenzhou, Zhejiang Province, 325027, China
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Umbilical cord blood-derived stem cells improve heat tolerance and hypothalamic damage in heat stressed mice. BIOMED RESEARCH INTERNATIONAL 2014; 2014:685683. [PMID: 24804231 PMCID: PMC3997876 DOI: 10.1155/2014/685683] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Revised: 02/07/2014] [Accepted: 03/18/2014] [Indexed: 11/17/2022]
Abstract
Heatstroke is characterized by excessive hyperthermia associated with systemic inflammatory responses, which leads to multiple organ failure, in which brain disorders predominate. This definition can be almost fulfilled by a mouse model of heatstroke used in the present study. Unanesthetized mice were exposed to whole body heating (41.2°C for 1 hour) and then returned to room temperature (26°C) for recovery. Immediately after termination of whole body heating, heated mice displayed excessive hyperthermia (body core temperature ~42.5°C). Four hours after termination of heat stress, heated mice displayed (i) systemic inflammation; (ii) ischemic, hypoxic, and oxidative damage to the hypothalamus; (iii) hypothalamo-pituitary-adrenocortical axis impairment (reflected by plasma levels of both adrenocorticotrophic-hormone and corticosterone); (iv) decreased fractional survival; and (v) thermoregulatory deficits (e.g., they became hypothermia when they were exposed to room temperature). These heatstroke reactions can be significantly attenuated by human umbilical cord blood-derived CD34(+) cells therapy. Our data suggest that human umbilical cord blood-derived stem cells therapy may improve outcomes of heatstroke in mice by reducing systemic inflammation as well as hypothalamo-pituitary-adrenocortical axis impairment.
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Tseng LS, Chen SH, Lin MT, Lin YC. Transplantation of human dental pulp-derived stem cells protects against heatstroke in mice. Cell Transplant 2014; 24:921-37. [PMID: 24612725 DOI: 10.3727/096368914x678580] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Stem cells from human exfoliated deciduous tooth pulp (SHED) is a promising approach for the treatment of stroke and spinal cord injury. In this study, we investigated the therapeutic effects of SHED for the treatment of multiple organ (including brain, particularly hypothalamus) injury in heatstroke mice. ICR male mice were exposed to whole body heating (WBH; 41.2°C, relative humidity 50-55%, for 1 h) and then returned to normal room temperature (26°C). We observed that intravenous administration of SHED immediately post-WBH exhibited the following therapeutic benefits for recovery after heatstroke: (a) inhibition of WBH-induced neurologic and thermoregulatory deficits; (b) reduction of WBH-induced ischemia, hypoxia, and oxidative damage to the brain (particularly the hypothalamus); (c) attenuation of WBH-induced increased plasma levels of systemic inflammatory response molecules, such as tumor necrosis factor-α and intercellular adhesion molecule-1; (d) improvement of WBH-induced hypothalamo-pituitary-adrenocortical (HPA) axis activity (as reflected by enhanced plasma levels of both adrenocorticotrophic hormone and corticosterone); and (e) attenuation of WBH-induced multiple organ apoptosis as well as lethality. In conclusion, post-WBH treatment with SHED reduced induction of proinflammatory cytokines and oxidative radicals, enhanced plasma induction of both adrenocorticotrophic hormone and corticosterone, and improved lethality in mouse heatstroke. The protective effect of SHED may be related to a decreased inflammatory response, decreased oxidative stress, and an increased HPA axis activity following the WBH injury.
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Affiliation(s)
- Ling-Shu Tseng
- School of Dentistry, Kaohsiung Medical University, Kaohsiung City, Taiwan
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Rakesh V, Stallings JD, Helwig BG, Leon LR, Jackson DA, Reifman J. A 3-D mathematical model to identify organ-specific risks in rats during thermal stress. J Appl Physiol (1985) 2013; 115:1822-37. [DOI: 10.1152/japplphysiol.00589.2013] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Early prediction of the adverse outcomes associated with heat stress is critical for effective management and mitigation of injury, which may sometimes lead to extreme undesirable clinical conditions, such as multiorgan dysfunction syndrome and death. Here, we developed a computational model to predict the spatiotemporal temperature distribution in a rat exposed to heat stress in an attempt to understand the correlation between heat load and differential organ dysfunction. The model includes a three-dimensional representation of the rat anatomy obtained from medical imaging and incorporates the key mechanisms of heat transfer during thermoregulation. We formulated a novel approach to estimate blood temperature by accounting for blood mixing from the different organs and to estimate the effects of the circadian rhythm in body temperature by considering day-night variations in metabolic heat generation and blood perfusion. We validated the model using in vivo core temperature measurements in control and heat-stressed rats and other published experimental data. The model predictions were within 1 SD of the measured data. The liver demonstrated the greatest susceptibility to heat stress, with the maximum temperature reaching 2°C higher than the measured core temperature and 95% of its volume exceeding the targeted experimental core temperature. Other organs also attained temperatures greater than the core temperature, illustrating the need to monitor multiple organs during heat stress. The model facilitates the identification of organ-specific risks during heat stress and has the potential to aid in the development of improved clinical strategies for thermal-injury prevention and management.
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Affiliation(s)
- Vineet Rakesh
- Department of Defense Biotechnology High Performance Computing Software Applications Institute, Telemedicine and Advanced Technology Research Center, United States Army Medical Research and Materiel Command, Fort Detrick, Maryland
| | - Jonathan D. Stallings
- Biomarkers Program, United States Army Center for Environmental Health Research, Fort Detrick, Maryland; and
| | - Bryan G. Helwig
- Thermal Mountain Medicine Division, United States Army Research Institute of Environmental Medicine, Natick, Massachusetts
| | - Lisa R. Leon
- Thermal Mountain Medicine Division, United States Army Research Institute of Environmental Medicine, Natick, Massachusetts
| | - David A. Jackson
- Biomarkers Program, United States Army Center for Environmental Health Research, Fort Detrick, Maryland; and
| | - Jaques Reifman
- Department of Defense Biotechnology High Performance Computing Software Applications Institute, Telemedicine and Advanced Technology Research Center, United States Army Medical Research and Materiel Command, Fort Detrick, Maryland
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10
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Chen SH, Lin MT, Chang CP. Ischemic and oxidative damage to the hypothalamus may be responsible for heat stroke. Curr Neuropharmacol 2013; 11:129-40. [PMID: 23997749 PMCID: PMC3637668 DOI: 10.2174/1570159x11311020001] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2012] [Revised: 09/12/2012] [Accepted: 12/14/2012] [Indexed: 12/11/2022] Open
Abstract
The hypothalamus may be involved in regulating homeostasis, motivation, and emotional behavior by controlling autonomic and endocrine activity. The hypothalamus communicates input from the thalamus to the pituitary gland, reticular activating substance, limbic system, and neocortex. This allows the output of pituitary hormones to respond to changes in autonomic nervous system activity. Environmental heat stress increases cutaneous blood flow and metabolism, and progressively decreases splanchnic blood flow. Severe heat exposure also decreases mean arterial pressure (MAP), increases intracranial pressure (ICP), and decreases cerebral perfusion pressure (CPP = MAP - ICP), all of which lead to cerebral ischemia and hypoxia. Compared with normothermic controls, rodents with heatstroke have higher hypothalamic values of cellular ischemia (e.g., glutamate and lactate-to-pyruvate ratio) and damage (e.g., glycerol) markers, pro-oxidant enzymes (e.g., lipid peroxidation and glutathione oxidation), proinflammatory cytokines (e.g., interleukin-1β and tumor necrosis factor-α), inducible nitric oxide synthase-dependent nitric oxide, and an indicator for the accumulation of polymorphonuclear leukocytes (e.g., myeloperoxidase activity), as well as neuronal damage (e.g., apoptosis, necrosis, and autophagy) after heatstroke. Hypothalamic values of antioxidant defenses (e.g., glutathione peroxidase and glutathione reductase), however, are lower. The ischemic, hypoxic, and oxidative damage to the hypothalamus during heatstroke may cause multiple organ dysfunction or failure through hypothalamic-pituitary-adrenal axis mechanisms. Finding the link between the signaling and heatstroke-induced hypothalamic oxidative and ischemic damage might allow us to clinically attenuate heatstroke. In particular, free radical scavengers, heat shock protein-70 inducers, hypervolemic hemodilution, inducible nitric oxide synthase inhibitors, progenitor stem cells, flutamide, estrogen, interleukin-1 receptor antagonists, glucocorticoid, activated protein C, and baicalin mitigate preclinical heatstroke levels.
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Affiliation(s)
- Sheng-Hsien Chen
- Department of Obstetrics and Gynecology, Chi Mei Medical Center, Tainan, Taiwan ; Department of Biotechnology, Southern Taiwan University of Science and Technology, Tainan, Taiwan
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Attenuating heatstroke-induced acute lung inflammation, edema, and injury in rats by exercise preconditioning. J Trauma Acute Care Surg 2013; 74:1052-9. [PMID: 23511144 DOI: 10.1097/ta.0b013e31827a3618] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND This study aimed to ascertain whether heat-induced acute lung edema, inflammation, and ischemic damage can be affected by heat shock protein 70 (HSP-70)-mediated exercise preconditioning (EP) in rats. METHODS Wistar rats were assigned to one of the following four groups: the non-EP + nonheated group, the non-EP + heated group, the EP + heated group, and the EP + HSP-70 antibodies + heated group. EP groups of animals were subjected to a protocol of running on a treadmill for 30 minutes at 20 m/min, 30 minutes at 30 m/min, and 60 minutes at 30 m/min after 1, 2, and 3 weeks of training, respectively. Heated group of animals, under general anesthesia, were put in a folded heating pad of 43°C for 68 minutes. Then, the heated animals were allowed to recover at room temperature. HSP-70 antibodies were injected intravenously 24 hours before heat exposure. RESULTS As compared with the non heated + non-EP rats, the heated + non-EP rats had significantly higher scores of alveolar edema, neutrophil infiltration, and hemorrhage, acute pleurisy, and increased bronchoalveolar fluid levels of proinflammatory cytokines and ischemic and oxidative damage markers. EP, in addition to inducing overexpression of HSP-70 in lung tissues, significantly attenuated heat-induced acute pulmonary edema, inflammation, and ischemic and oxidative damage in the lungs. HSP-70 antibodies, in addition to reducing HSP-70 expression in the lungs, significantly attenuated the beneficial effects of EP in reducing acute lung inflammation and injury. CONCLUSION EP may attenuate the occurrence of pulmonary edema, inflammation, as well as ischemic and oxidative damage caused by heatstroke by up-regulating HSP-70 in the lungs.
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Yamakawa K, Matsumoto N, Imamura Y, Muroya T, Yamada T, Nakagawa J, Shimazaki J, Ogura H, Kuwagata Y, Shimazu T. Electrical vagus nerve stimulation attenuates systemic inflammation and improves survival in a rat heatstroke model. PLoS One 2013; 8:e56728. [PMID: 23424673 PMCID: PMC3570456 DOI: 10.1371/journal.pone.0056728] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2012] [Accepted: 01/14/2013] [Indexed: 11/21/2022] Open
Abstract
This study was performed to gain insights into novel therapeutic approaches for the treatment of heatstroke. The central nervous system regulates peripheral immune responses via the vagus nerve, the primary neural component of the cholinergic anti-inflammatory pathway. Electrical vagus nerve stimulation (VNS) reportedly suppresses pro-inflammatory cytokine release in several models of inflammatory disease. Here, we evaluated whether electrical VNS attenuates severe heatstroke, which induces a systemic inflammatory response. Anesthetized rats were subjected to heat stress (41.5°C for 30 minutes) with/without electrical VNS. In the VNS-treated group, the cervical vagus nerve was stimulated with constant voltage (10 V, 2 ms, 5 Hz) for 20 minutes immediately after completion of heat stress. Sham-operated animals underwent the same procedure without stimulation under a normothermic condition. Seven-day mortality improved significantly in the VNS-treated group versus control group. Electrical VNS significantly suppressed induction of pro-inflammatory cytokines such as tumor necrosis factor-α and interleukin-6 in the serum 6 hours after heat stress. Simultaneously, the increase of soluble thrombomodulin and E-selectin following heat stress was also suppressed by VNS treatment, suggesting its protective effect on endothelium. Immunohistochemical analysis using tissue preparations obtained 6 hours after heat stress revealed that VNS treatment attenuated infiltration of inflammatory (CD11b-positive) cells in lung and spleen. Interestingly, most cells with increased CD11b positivity in response to heat stress did not express α7 nicotinic acetylcholine receptor in the spleen. These data indicate that electrical VNS modulated cholinergic anti-inflammatory pathway abnormalities induced by heat stress, and this protective effect was associated with improved mortality. These findings may provide a novel therapeutic strategy to combat severe heatstroke in the critical care setting.
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Affiliation(s)
- Kazuma Yamakawa
- Department of Traumatology and Acute Critical Medicine, Osaka University Graduate School of Medicine, Osaka, Japan.
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Wang CT, Lin HJ, Cheng BC, Lin MT, Chang CP. Attenuating systemic inflammatory markers in simulated high-altitude exposure by heat shock protein 70-mediated hypobaric hypoxia preconditioning in rats. J Formos Med Assoc 2013; 114:328-38. [PMID: 25839766 DOI: 10.1016/j.jfma.2012.11.015] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2012] [Revised: 10/22/2012] [Accepted: 11/23/2012] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND/PURPOSE The primary goal of this study was to test whether high-altitude exposure (HAE: 0.9% O(2) at 0.47 ATA for 24 hours) was capable of increasing the systemic inflammatory markers as well as the toxic organ injury indicators in rats, with a secondary goal to test whether preinduction of heat shock protein (HSP) 70 by hypobaric hypoxia preconditioning (HHP: 18.3% O(2) at 0.66 ATA for 5 h/day on 5 days consecutively for 2 weeks) attenuated the proposed increased serum levels of both the systemic inflammatory markers and the toxic organ injury indicators. METHODS Rats were assigned to: (1) non-HHP (21% O(2) at 1.0 ATA)+non-HAE (21% O(2) at 1.0 ATA) group; (2) non-HHP+HAE group; (3) HHP+non-HAE group; (4) HHP+HAE group; and (5) HHP+HSP70 antibodies (Ab)+HAE group. For the HSP70Ab group, a neutralizing HSP70Ab was injected intravenously at 24 hours prior to HAE. All the physiological and biochemical parameters were obtained at the end of HAE or the equivalent time period of non-HAE. Blood samples were obtained for determination of both the systemic inflammatory markers (e.g., serum tumor necrosis factor-α, interleukin-1β, E-selectin, intercellular adhesion molecule-1, and liver myeloperoxidase activity) and the toxic organ injury indicators (e.g., nitric oxide metabolites, 2,3-dihydroxybenzoic acid, and lactate dehydrogenase). RESULTS HHP, in addition to inducing overexpression of tissue HSP70, significantly attenuated the HAE-induced hypotension, bradycardia, hypoxia, acidosis, and increased tissue levels of both the systemic inflammatory markers and the toxic organ injury indicators. The beneficial effects of HHP in inducing tissue overexpression of HSP70 as well as in preventing the HAE-induced increased levels of the systemic inflammatory markers and the toxic organ injury indicators could be significantly reduced by HSP70Ab preconditioning. CONCLUSION These results suggest that HHP may downgrade both the systemic inflammatory markers and the toxic organ injury indicators in HAE by upregulating tissue HSP70.
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Affiliation(s)
- Chia-Ti Wang
- Department of Emergency Medicine, Chi Mei Medical Center, Tainan, Taiwan
| | - Hung-Jung Lin
- Department of Emergency Medicine, Chi Mei Medical Center, Tainan, Taiwan; Department of Biotechnology, Southern Taiwan University of Science and Technology, Tainan, Taiwan
| | - Bor-Chih Cheng
- Department of Biotechnology, Southern Taiwan University of Science and Technology, Tainan, Taiwan; Department of Surgery, Chi Mei Medical Center, Tainan, Taiwan
| | - Mao-Tsun Lin
- Department of Medical Research, Chi Mei Medical Center, Tainan, Taiwan
| | - Ching-Ping Chang
- Department of Biotechnology, Southern Taiwan University of Science and Technology, Tainan, Taiwan.
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Wang LC, Chang CP, Chio CC, Wu MH, Lee YS, Huang CY, Tsai KJ. Hypobaric hypoxia preconditioning attenuates experimental heatstroke syndromes via preinduction of heat shock protein 70. Am J Med Sci 2012; 344:383-90. [PMID: 22245947 DOI: 10.1097/maj.0b013e31824314fe] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
INTRODUCTION Heatstroke has been defined as a form of hyperthermia associated with a systemic inflammatory response that leads to multiple organ dysfunction syndrome (MODS). It has also been documented that heat shock protein 70 (HSP70) preconditioning is able to induce thermotolerance. Here, the authors further investigated whether hypobaric hypoxia preconditioning (HHP) improved the MODS in heatstroke by up-regulation of HSP70. METHODS Anesthetized rats were randomly assigned to (a) non-HHP + nonheated group, (b) non-HHP + heated group, (c) HHP + heated group and (d) HHP + HSP70 antibodies (Abs) + heated groups. All heated groups were exposed to heat stress (43°C, 70 minutes) to induce heatstroke. For HHP, animals were exposed to 0.66 atmosphere absolute (18.3% O2) for 5 hours daily for consecutive 5 days per week for 2 weeks before the start of heat exposure. RESULTS HHP significantly (i) attenuated hypotension, (ii) reduced plasma index of the toxic oxidizing radicals and the organ injury indicator, (iii) attenuated plasma systemic inflammatory response molecules, (iv) reduced an index of infiltration of polymorphonuclear neutrophils in the lung like myeloper-oxidase activity, (v) promoted plasma levels of an anti-inflammatory cytokine, interleukin-10, (vi) promoted the survival time to fourfold compared with non-HHP group and (vii) promoted the overexpression of HSP70 in different organs (eg, the lung) during heatstroke. The beneficial effects of HHP could be significantly attenuated by HSP70 Ab preconditioning. CONCLUSION Our results show that HHP protects rats from heat-induced MODS via up-regulating HSP70. Thus, HHP could be a novel strategy for the prevention of heatstroke animals or patients before heat exposure.
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Affiliation(s)
- Liang-Chao Wang
- Institute of Clinical Medicine, Department of Surgery, National Cheng-Kung University Hospital, Tainan, Taiwan
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Attenuating brain inflammation, ischemia, and oxidative damage by hyperbaric oxygen in diabetic rats after heat stroke. J Formos Med Assoc 2012; 112:454-62. [PMID: 24016610 DOI: 10.1016/j.jfma.2012.02.017] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2011] [Revised: 02/06/2012] [Accepted: 02/07/2012] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND/PURPOSE Alternating hypothalamic-pituitary-adrenal axis mechanisms would lead to multiple organs dysfunction or failure. Herein, we attempt to assess whether hypothalamic inflammation and ischemic and oxidative damage that occurred during heatstroke (HS) can be affected by hyperbaric oxygen (HBO₂) therapy in streptozotocin-induced diabetic rats. METHODS In this study, anesthetized diabetic rats, immediately after the onset of HS, were divided into two major groups and given the normobaric air (21% O₂ at 1.0 atmospheres absolute) or HBO₂ (100% O₂ at 2.0 atmospheres absolute). HS was induced by exposing the animals to heat stress (43°C). Another group of anesthetized diabetic rats was kept at normothermic state and used as controls. RESULTS The survival time values for the HBO2-treated HS-diabetic rats increased form the control values of 78-82 minutes to new values of 184-208 minutes. HBO₂ therapy caused a reduction of HS-induced cellular ischemia (e.g., increased cellular levels of glutamate and lactate/pyruvate ratio), hypoxia (e.g., decreased cellular levels of PO₂), inflammation (e.g., increased cellular levels of interleukin-1β, tumor necrosis factor-alpha, interleukin-6, and myeloperoxidase), and oxidative damage (e.g., increased values of nitric oxide, 2,3-dihydroxybenzoic acid, glycerol, and neuronal damage score) in the hypothalamus of the diabetic rats. CONCLUSION Our results suggest that, in diabetic animals, HBO2 therapy may improve outcomes of HS in part by reducing heat-induced activated inflammation and ischemic and oxidative damage in the hypothalamus and other brain regions.
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Hong JY, Lai YC, Chang CY, Chang SC, Tang GJ. Successful treatment of severe heatstroke with therapeutic hypothermia by a noninvasive external cooling system. Ann Emerg Med 2011; 59:491-3. [PMID: 21982153 DOI: 10.1016/j.annemergmed.2011.09.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2011] [Revised: 09/13/2011] [Accepted: 09/19/2011] [Indexed: 10/16/2022]
Abstract
Heatstroke is a life-threatening disease; however, no pharmacologic treatment has proven to be effective. In severe cases with multiple organ dysfunction, the mortality remains high and many patients inevitably develop permanent neurologic damage. We report a near-fatal case of exertional heatstroke with multiple organ dysfunction, including generalized convulsions, acute lung injury, and disseminated intravascular coagulation, successfully treated with induced therapeutic hypothermia (33°C [91.4°F]) by a noninvasive external cooling system. After treatment, the patient completely recovered, without any neurologic sequelae during 1 year of follow-up. To our knowledge, this is the first reported case of using therapeutic hypothermia in heatstroke.
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Affiliation(s)
- Jen-Yee Hong
- Department of Internal Medicine, National Yang-Ming University Hospital, Yilan City, Taiwan
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Hypobaric hypoxia preconditioning attenuates acute lung injury during high-altitude exposure in rats via up-regulating heat-shock protein 70. Clin Sci (Lond) 2011; 121:223-31. [PMID: 21599636 DOI: 10.1042/cs20100596] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
HHP (hypobaric hypoxia preconditioning) induces the overexpression of HSP70 (heat-shock protein 70), as well as tolerance to cerebral ischaemia. In the present study, we hypothesized that HHP would protect against HAE (high-altitude exposure)-induced acute lung injury and oedema via promoting the expression of HSP70 in lungs prior to the onset of HAE. At 2 weeks after the start of HHP, animals were exposed to a simulated HAE of 6000 m in a hypobaric chamber for 24 h. Immediately after being returned to ambient pressure, the non-HHP animals had higher scores of alveolar oedema, neutrophil infiltration and haemorrhage, acute pleurisy (e.g. increased exudate volume, increased numbers of polymorphonuclear cells and increased lung myeloperoxidase activity), increased pro-inflammatory cytokines [e.g. TNF-α (tumour necrosis factor-α), IL (interleukin)-1β and IL-6], and increased cellular ischaemia (i.e. glutamate and lactate/pyruvate ratio) and oxidative damage [glycerol, NOx (combined nitrate+nitrite) and 2,3-dihydroxybenzoic acid] markers in the BALF (bronchoalveolar fluid). HHP, in addition to inducing overexpression of HSP70 in the lungs, significantly attenuated HAE-induced pulmonary oedema, inflammation, and ischaemic and oxidative damage in the lungs. The beneficial effects of HHP in preventing the occurrence of HAE-induced pulmonary oedema, inflammation, and ischaemic and oxidative damage was reduced significantly by pretreatment with a neutralizing anti-HSP70 antibody. In conclusion, HHP may attenuate the occurrence of pulmonary oedema, inflammation, and ischaemic and oxidative damage caused by HAE in part via up-regulating HSP70 in the lungs.
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Lin XJ, Mei GP, Liu J, Li YL, Zuo D, Liu SJ, Zhao TB, Lin MT. Therapeutic effects of melatonin on heatstroke-induced multiple organ dysfunction syndrome in rats. J Pineal Res 2011; 50:436-44. [PMID: 21392091 DOI: 10.1111/j.1600-079x.2011.00863.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Melatonin reportedly exerts beneficial effects to attenuate multiple organ dysfunction syndrome (MODS) in septic shock. Heatstroke resembles septic shock in many aspects. Thus, this study was performed on the anesthetized rats by using heat exposure to induce heatstroke-associated MODS. We evaluated the effect of melatonin, a versatile molecule synthesized in the pineal gland and in many organs, in heatstroke rats and showed that melatonin (0.2-5.0 mg/kg of body weight, i.v., immediately after the start of heat stress) significantly (i) attenuated hyperthermia, hypotension and hypothalamic ischemia and hypoxia, (ii) reduced plasma index of the toxic oxidizing radicals like nitric oxide metabolites and hydroxyl radicals, (iii) diminished plasma index of hepatic and renal dysfunction like creatinine, blood urea nitrogen, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and lactate dehydrogenase, (iv) attenuated plasma systemic inflammation response molecules like soluble intercellular and lesion molecule-1, E-selectin, tumor necrosis factor-alpha, interleukin (IL)-1β, and IL-6, (v) promoted plasma levels of an anti-inflammatory cytokine IL-10, (vi) reduced an index of infiltration of polymorphonuclear neutrophils in the lung like myeloperoxidase activity, and (vii) promoted the survival time to fourfold compared with the heatstroke alone group. Thus, melatonin could be a novel agent for the treatment of heatstroke animals or patients in the early stage.
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Affiliation(s)
- Xiao-Jing Lin
- Rehabilitation Department of Spinal Cord Injury, General Hospital Jinan Military, Shandong, China
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Hsi-Hsing Y, Ching-Ping C, Juei-Tang C, Lin MT. Inhibition of acute lung inflammation and injury is a target of brain cooling after heatstroke injury. ACTA ACUST UNITED AC 2010; 69:805-12. [PMID: 20400921 DOI: 10.1097/ta.0b013e3181cb43fd] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Although brain cooling has recently been reported as effective in improving the survival after heatstroke generation in rats, the mechanisms underlying the therapeutic effects of brain cooling are not fully elucidated. This study was conducted to test whether the acute lung inflammation and damage that might occur during heatstroke could be affected by brain cooling. METHODS Anesthetized rats were randomized into four groups as follows: (a) normothermic controls (n = 8); (b) heatstroke rats without saline delivery (n = 8); (c) heatstroke rats treated with 36°C saline via retrograde jugular vein (n = 8); and (d) heatstroke rats treated with 4°C saline via retrograde jugular vein (n = 8). Heatstroke was induced by putting the animals in a folded heating pad of 42°C for 68 minutes controlled by circulating hot water. The core temperatures of normothermic groups were maintained at about 36°C. The cardiovascular parameters and core temperatures were monitored for all experiments. Bronchoalveolar lavage (BAL) was done in the left lung 20 minutes after termination of heat stress for determination of cellular ischemia markers (e.g., glutamate, lactate-to-pyruvate ratio), proinflammatory cytokines (interleukin-1, tumor necrosis factor-alpha), and nitric oxide metabolites. Parts of the right lung were excised for meloperoxidase measurement, whereas the rest was collected for lung damage score assessments. RESULTS When compared with those of normothermic controls, untreated or 36°C saline-treated heatstroke rats had higher values of BAL fluid levels of cellular ischemia markers, proinflammatory cytokines, nitric oxide metabolites, lung meroperoxidase activity, lung damage score, and neutrophil infiltration. Brain cooling causes by 4°C saline infusion significantly reduced the heat-induced increased BAL levels of cellular ischemia markers, proinflammatory cytokines, and nitric oxide metabolites, and reduced lung damage score and neutrophil infiltration. CONCLUSIONS These experimental data indicate that acute lung inflammation and damage is a target of brain cooling after heatstroke injury.
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Affiliation(s)
- Yang Hsi-Hsing
- Institute of Basic Medical Sciences, National Cheng Kung University, Tainan, Taiwan
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Zhao YQ, Gao JT, Liu SH, Wu Y, Lin MT, Fan M. Geranylgeranylacetone preconditioning may attenuate heat-induced inflammation and multiorgan dysfunction in rats. J Pharm Pharmacol 2010; 62:99-105. [DOI: 10.1211/jpp.62.01.0011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Abstract
Objectives
Geranylgeranylacetone, an acyclic isoprenoid, is a non-toxic inducer of heat shock protein (HSP)70. HSP70 overproduction is associated with heat tolerance in rats. This study aimed to investigate whether geranylgeranylacetone preconditioning of rats reduced heat-induced inflammation and multiple organ dysfunction.
Methods
Anaesthetised rats were given vehicle or geranylgeranylacetone (800 mg/kg) orally. After 48 h they were exposed to ambient temperature of 43°C for 70 min to induce heatstroke. Another group of rats kept at room temperature were used as normothermic controls.
Key findings
Vehicle-treated rats all succumbed to heat stress; their survival time was 25 ± 4 min. Pretreatment with geranylgeranylacetone significantly increased survival time to 92 ± 15 min. Compared with normothermic controls, all vehicle-treated heatstroke rats displayed hepatic and renal dysfunction (e.g. increased plasma levels of serum urea nitrogen, creatinine, aspartate aminotransferase, alanine aminotransferase and alkaline phosphatase) and active inflammation (e.g. increased plasma and brain levels of interleukin-1β, tumour necrosis factor-α and interleukin-6). These heat-stress response indicators were all significantly suppressed by geranylgeranylacetone pretreatment. In addition, the plasma and brain levels of interleukin-10 (an anti-inflammatory cytokine) and brain levels of HSP70 were significantly increased after geranylgeranylacetone preconditioning during heatstroke.
Conclusions
Geranylgeranylacetone preconditioning attenuates heat-induced inflammation and multiorgan dysfunction in rats.
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Affiliation(s)
- Yong-Qi Zhao
- Department of Brain Protection and Plasticity, Institute of Basic Medical Sciences, Beijing, 100850, China
| | - Jun-Tao Gao
- Department of Physiology, Jilin Medical College, Jilin, 132013, China
| | - Shou-Hong Liu
- Department of Brain Protection and Plasticity, Institute of Basic Medical Sciences, Beijing, 100850, China
| | - Yan Wu
- Department of Brain Protection and Plasticity, Institute of Basic Medical Sciences, Beijing, 100850, China
| | - Mao-Tsun Lin
- Department of Medical Research, Chi Mei Medical Center, Tainan, Taiwan, China
| | - Ming Fan
- Department of Brain Protection and Plasticity, Institute of Basic Medical Sciences, Beijing, 100850, China
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Yang HH, Chang CP, Cheng RT, Lin MT. Attenuation of acute lung inflammation and injury by whole body cooling in a rat heatstroke model. J Biomed Biotechnol 2009; 2009:768086. [PMID: 20037732 PMCID: PMC2796336 DOI: 10.1155/2009/768086] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2009] [Revised: 09/25/2009] [Accepted: 10/01/2009] [Indexed: 12/21/2022] Open
Abstract
Whole body cooling is the current therapy of choice for heatstroke because the therapeutic agents are not available. In this study, we assessed the effects of whole body cooling on several indices of acute lung inflammation and injury which might occur during heatstroke. Anesthetized rats were randomized into the following groups and given (a) no treatment or (b) whole body cooling immediately after onset of heatstroke. As compared with the normothermic controls, the untreated heatstroke rats had higher levels of pleural exudates volume and polymorphonuclear cell numbers, lung myloperoxidase activity and inducible nitric oxide synthase expression, histologic lung injury score, and bronchoalveolar proinflammatory cytokines and glutamate, and PaCO2. In contrast, the values of mean arterial pressure, heart rate, PaO2, pH, and blood HCO3(-) were all significantly lower during heatstroke. The acute lung inflammation and injury and electrolyte imbalance that occurred during heatstroke were significantly reduced by whole body cooling. In conclusion, we identified heat-induced acute lung inflammation and injury and electrolyte imbalance could be ameliorated by whole body cooling.
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Affiliation(s)
- Hsi-Hsing Yang
- Institute of Pharmacology, National Cheng Kung University Medical School, Tainan 701, Taiwan
- Department of Internal Medicine, Chi Mei Medical Center, Tainan 710, Taiwan
| | - Ching-Ping Chang
- Department of Biotechnology, Southern Taiwan University, Tainan 710, Taiwan
| | - Ruei-Tang Cheng
- Department of Medical Research, Chi Mei Medical Center, Tainan 710, Taiwan
| | - Mao-Tsun Lin
- Department of Medical Research, Chi Mei Medical Center, Tainan 710, Taiwan
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Activated protein C improves heatstroke outcomes through restoration of normal hypothalamic and thermoregulatory function. Am J Med Sci 2009; 338:382-7. [PMID: 19773641 DOI: 10.1097/maj.0b013e3181b272ae] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Human recombinant activated protein C (APC) has been found to be beneficial in treating heatstroke in both humans and rats. Here, we further investigated the possible mechanism underlying the therapeutic action exerted by APC in experimental heatstroke. METHODS Unanesthetized and unrestrained mice were exposed to an ambient temperature of 42.4 degrees C for 1 hour to induce heatstroke. They were given normal saline or APC (5 mg/kg of body weight, intravenously) 1 hour after the termination of heat stress. Their physiologic and biochemical parameters were continuously monitored for 4 hours after cessation of heat stress. Mice that survived on day 4 of heat treatment were considered survivors. RESULTS When the vehicle-treated mice underwent heat treatment, the fraction survival and core temperature at 4 hours of body heating were found to be 0 of 12 and 33.8 +/- 0.6 degrees C, respectively. Administration of APC 1 hour after the cessation of heat stress rescued the mice from heat-induced death (fraction survival, 12 of 12) and reduced hypothermia (core temperature, 37.4 +/- 0.2 degrees C). Heat-induced apoptosis in the hypothalamus was significantly reduced by APC. The increased levels of cellular ischemia (eg, glutamate, lactate-to-pyruvate ratio, nitrite, and dihydroxybenzoic acid) and damage (eg, glycerol) markers in the hypothalamus during heatstroke were also decreased significantly by APC therapy. The hypothalamic levels of tumor necrosis factor-alpha (a proinflammatory cytokine) that are upregulated in heat-stressed mice were significantly lower in APC-administered mice. CONCLUSIONS Our results show that human recombinant APC improves heatstroke through restoration of normal hypothalamic and thermoregulatory function.
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Lin XJ, Li YL, Mei GP, Zou F, He DD, Liu XQ, Li YJ, Zhao TB, Lin MT. ACTIVATED PROTEIN C CAN BE USED AS A PROPHYLACTIC AS WELL AS A THERAPEUTIC AGENT FOR HEAT STROKE IN RODENTS. Shock 2009; 32:524-9. [DOI: 10.1097/shk.0b013e3181a1a75d] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Hostler D, Northington WE, Callaway CW. High-dose diazepam facilitates core cooling during cold saline infusion in healthy volunteers. Appl Physiol Nutr Metab 2009; 34:582-6. [PMID: 19767791 DOI: 10.1139/h09-011] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Studies have suggested that inducing mild hypothermia improves neurologic outcomes after traumatic brain injury, major stroke, cardiac arrest, or exertional heat illness. While infusion of cold normal saline is a simple and inexpensive method for reducing core temperature, human cold-defense mechanisms potentially make this route stressful or ineffective. We hypothesized that intravenous administration of diazepam during a rapid infusion of 30 mL.kg-1 of cold (4 degrees C) 0.9% saline to healthy subjects would be more comfortable and reduce core body temperature more than the administration of cold saline alone. Fifteen subjects received rapidly infused cold (4 degrees C) 0.9% saline. Subjects were randomly assigned to receive, intravenously, 20 mg diazepam (HIGH), 10 mg diazepam (LOW), or placebo (CON). Main outcomes were core temperature, skin temperature, and oxygen consumption. Data for the main outcomes were analyzed with generalized estimating equations to identify differences in group, time, or a group x time interaction. Core temperature decreased in all groups (CON, 1.0 +/- 0.2 degrees C; LOW, 1.4 +/- 0.2 degrees C; HIGH, 1.5 +/- 0.2 degrees C), while skin temperature was unchanged. Mean (95% CI) oxygen consumption was 315.3 (253.8, 376.9) mL.kg-1.min-1 in the CON group, 317.9 (275.5, 360.3) in the LOW group, and 226.1 (216.4, 235.9) in the HIGH group. Significant time and group x time interaction was observed for core temperature and oxygen consumption (p < 0.001). Administration of high-dose diazepam resulted in decreased oxygen consumption during cold saline infusion, suggesting that 20 mg of intravenous diazepam may reduce the shivering threshold without compromising respiratory or cardiovascular function.
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Affiliation(s)
- David Hostler
- University of Pittsburgh, Department of Emergency Medicine, Pittsburgh, PA 15213, USA.
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Trujillo MH, Bellorin-Font E, Fragachan CF, Perret-Gentil R. Multiple Organ Failure Following Near Fatal Exertional Heat Stroke. J Intensive Care Med 2009; 24:72-8. [PMID: 19017664 DOI: 10.1177/0885066608327122] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
We describe the clinical features of a patient with near-fatal heat stroke who was admitted to our intensive care unit. A 14-year-old girl became convulsive and hyperthermic when participating in a strenuous hike under direct sunlight in a hilly area in Venezuela on a very hot and humid day. During the following days, she developed multiple organ failure, including neurological impairment, acute renal failure, disseminated intravascular coagulation, and extensive hepatic and muscle damage. Treatment consisted of ventilatory support, hemodialysis, corticosteroids, and enteral nutrition. This case of multiple organ failure following near-fatal heat stroke illustrates that although there are no specific techniques and measures for the treatment of this condition, intensive care management and conservative strategies can result in patient survival and complete recovery.
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Affiliation(s)
- Maximo H Trujillo
- Critical Care Units and Division of Nephrology, The University Hospital of Caracas, Caracas, Venezuela.
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Shen KH, Chang CK, Lin MT, Chang CP. Interleukin-1 receptor antagonist restores homeostatic function and limits multiorgan damage in heatstroke. Eur J Appl Physiol 2008; 103:561-8. [DOI: 10.1007/s00421-008-0755-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/23/2008] [Indexed: 10/22/2022]
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Hwang WS, Chen SH, Lin CH, Chang HK, Chen WC, Lin MT. Human umbilical cord blood-derived CD34+ cells can be used as a prophylactic agent for experimental heatstroke. J Pharmacol Sci 2008; 106:46-55. [PMID: 18187924 DOI: 10.1254/jphs.fp0071567] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Abstract
We attempted to assess the prophylactic effect of human umbilical cord blood-derived CD34(+) cells in experimental heatstroke. Anesthetized rats, 1 day before heat stress, were divided into 2 major groups and given CD34(-) cells (defined by 1 x 10(6) human cord blood lymphocytes and monocytes that contained <0.2% CD34(+) cells) or CD34(+) cells (defined by 1 x 10(6) human cord blood lymphocytes and monocytes that contained >95% CD34(+) cells). They were exposed to ambient temperature of 43 degrees C for 70 min to induce heatstroke. When the CD34(-) cells-treated or untreated rats underwent heat stress, their survival time values were found to be 20-24 min. Pretreatment with CD34(+) cells significantly increased survival time (123-351 min). As compared with normothermic controls, all CD34(-) cells-treated heatstroke animals displayed hypotension, hepatic and renal failure, hypercoagulable state, activated inflammation, and cerebral ischemia and injury. However, these heatstroke reactions all were significantly suppressed by CD34(+) cells pretreatment. In addition, the levels of interleukin-10 in plasma and glial cell line-derived neurotrophic factors in brain were all significantly increased after CD34(+) cell administration during heatstroke. Our data indicate that human umbilical cord-derived CD34(+) cells can be used as a prophylactic agent for experimental heatstroke.
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Affiliation(s)
- Wei-Shou Hwang
- Department of Hematology and Oncology, Chi Mei Medical Center, Tainan, Taiwan
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In this issue. Resuscitation 2007. [DOI: 10.1016/j.resuscitation.2007.04.025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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