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Moretti EH, Lino CA, Steiner AA. INTERPLAY BETWEEN BRAIN OXYGENATION AND THE DEVELOPMENT OF HYPOTHERMIA IN ENDOTOXIC SHOCK. Shock 2024; 61:861-868. [PMID: 38662598 DOI: 10.1097/shk.0000000000002350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2024]
Abstract
ABSTRACT There is evidence to suggest that the hypothermia observed in the most severe cases of systemic inflammation or sepsis is a regulated response with potential adaptive value, but the mechanisms involved are poorly understood. Here, we investigated the interplay between brain oxygenation (assessed by tissue P o2 ) and the development of hypothermia in unanesthetized rats challenged with a hypotension-inducing dose of bacterial LPS (1 mg/kg i.v.). At an ambient temperature of 22°C, oxygen consumption (V̇O 2 ) began to fall only a few minutes after the LPS injection, and this suppression in metabolic rate preceded the decrease in core temperature. No reduction in brain P o2 was observed prior to the development of the hypometabolic, hypothermic response, ruling out the possibility that brain hypoxia served as a trigger for hypothermia in this model. Brain P o2 was even increased. Such an improvement in brain oxygenation could reflect either an increased O 2 delivery or a decreased O 2 consumption. The former explanation seems unlikely because blood flow (cardiac output) was being progressively decreased during the recording period. On the other hand, the decrease in V̇O 2 usually preceded the rise in P o2 , and an inverse correlation between V̇O 2 and brain P o2 was consistently observed. These findings do not support the existence of a closed-loop feedback relationship between brain oxygenation and hypothermia in systemic inflammation. The data are consistent with a feedforward mechanism in which hypothermia is triggered (possibly by cryogenic inflammatory mediators) in anticipation of changes in brain oxygenation to prevent the development of tissue hypoxia.
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Affiliation(s)
- Eduardo H Moretti
- Departamento de Imunologia, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo, SP, Brazil
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Duque-Wilckens N, Maradiaga N, Szu-Ying Y, Joseph D, Srinavasan V, Thelen K, Sotomayor F, Durga K, Nestler E, Moeser AJ, Robison AJ. Activity-dependent FosB gene expression negatively regulates mast cell functions. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.06.592755. [PMID: 38766119 PMCID: PMC11100602 DOI: 10.1101/2024.05.06.592755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
Mast cells are innate immune cells that play a crucial role in numerous physiological processes across tissues by releasing pre-stored and newly synthesized mediators in response to stimuli, an activity largely driven by changes in gene expression. Given their widespread influence, dysfunction in mast cells can contribute to a variety of pathologies including allergies, long COVID, and autoimmune and neuroinflammatory disorders. Despite this, the specific transcriptional mechanisms that control mast cell mediator release remain poorly understood, significantly hindering the development of effective therapeutic strategies. We found that the two proteins encoded by the transcription factor FosB, FOSB and the highly stable variant ΔFOSB, are robustly expressed upon stimulation in both murine and human mast cell progenitors. Motivated by these findings, we generated a novel mouse model with targeted ablation of FosB gene expression specifically in mast cells (MC FosB- ) by crossing a mast cell-specific Cre reporter line (Mcpt5-Cre) with a Cre-dependent floxed FosB mouse lines. We found that mast cell progenitors derived from MC FosB- mice, compared to wild types (WT), exhibit baseline increased histamine content and vesicle numbers. Additionally, they show enhanced calcium mobilization, degranulation, and histamine release following allergy-related IgE-mediated stimulation, along with heightened IL-6 release in response to infection-like LPS stimulation. In vivo experiments with IgE- mediated and LPS challenges revealed that MC FosB- mice experience greater drops in body temperature, heightened activation of tissue-resident mast cells, and increased release of pro-inflammatory mediators compared to their WT counterparts. These findings suggest that FosB products play a crucial regulatory role in moderating stimulus-induced mast cell activation in response to both IgE and LPS stimuli. Lastly, by integrating CUT&RUN and RNAseq data, we identified several genes targeted by ΔFOSB that could mediate these observed effects, including Mir155hg, CLCF1, DUSP4, and Trib1. Together, this study provides the first evidence that FOSB/ΔFOSB modulate mast cell functions and provides a new possible target for therapeutic interventions aimed at ameliorating mast cell-related diseases.
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Moretti EH, Rodrigues AC, Marques BV, Totola LT, Ferreira CB, Brito CF, Matos CM, da Silva FA, Santos RAS, Lopes LB, Moreira TS, Akamine EH, Baccala LA, Fujita A, Steiner AA. Autoregulation of blood flow drives early hypotension in a rat model of systemic inflammation induced by bacterial lipopolysaccharide. PNAS NEXUS 2023; 2:pgad014. [PMID: 36874271 PMCID: PMC9982072 DOI: 10.1093/pnasnexus/pgad014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 01/09/2023] [Indexed: 01/22/2023]
Abstract
Uncontrolled vasodilation is known to account for hypotension in the advanced stages of sepsis and other systemic inflammatory conditions, but the mechanisms of hypotension in earlier stages of such conditions are not clear. By monitoring hemodynamics with the highest temporal resolution in unanesthetized rats, in combination with ex-vivo assessment of vascular function, we found that early development of hypotension following injection of bacterial lipopolysaccharide is brought about by a fall in vascular resistance when arterioles are still fully responsive to vasoactive agents. This approach further uncovered that the early development of hypotension stabilized blood flow. We thus hypothesized that prioritization of the local mechanisms of blood flow regulation (tissue autoregulation) over the brain-driven mechanisms of pressure regulation (baroreflex) underscored the early development of hypotension in this model. Consistent with this hypothesis, an assessment of squared coherence and partial-directed coherence revealed that, at the onset of hypotension, the flow-pressure relationship was strengthened at frequencies (<0.2 Hz) known to be associated with autoregulation. The autoregulatory escape to phenylephrine-induced vasoconstriction, another proxy of autoregulation, was also strengthened in this phase. The competitive demand that drives prioritization of flow over pressure regulation could be edema-associated hypovolemia, as this became detectable at the onset of hypotension. Accordingly, blood transfusion aimed at preventing hypovolemia brought the autoregulation proxies back to normal and prevented the fall in vascular resistance. This novel hypothesis opens a new avenue of investigation into the mechanisms that can drive hypotension in systemic inflammation.
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Affiliation(s)
- Eduardo H Moretti
- Departamento de Imunologia, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Av. Prof. Lineu Prestes, 1730, Sao Paulo, SP 05508-000, Brazil
| | - Abner C Rodrigues
- Instituto Internacional de Neurociencias Edmond e Lily Safra, Instituto de Ensino e Pesquisa Alberto Santos Dumont, Macaiba, RN 59288-899, Brazil
| | - Bruno V Marques
- Departamento de Farmacologia, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo, SP 05508-000, Brazil
| | - Leonardo T Totola
- Departamento de Fisiologia e Biofisica, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo, SP 05508-000, Brazil
| | - Caroline B Ferreira
- Departamento de Farmacologia, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo, SP 05508-000, Brazil.,Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213-2548, USA
| | - Camila F Brito
- Departamento de Imunologia, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Av. Prof. Lineu Prestes, 1730, Sao Paulo, SP 05508-000, Brazil
| | - Caroline M Matos
- Departamento de Imunologia, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Av. Prof. Lineu Prestes, 1730, Sao Paulo, SP 05508-000, Brazil
| | - Filipe A da Silva
- Departamento de Fisiologia e Biofisica, Instituto de Ciencias Biologias, Universidade Federal de Minas Gerais, Belo Horizonte, MG 31270-901, Brazil
| | - Robson A S Santos
- Departamento de Fisiologia e Biofisica, Instituto de Ciencias Biologias, Universidade Federal de Minas Gerais, Belo Horizonte, MG 31270-901, Brazil
| | - Luciana B Lopes
- Departamento de Farmacologia, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo, SP 05508-000, Brazil
| | - Thiago S Moreira
- Departamento de Fisiologia e Biofisica, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo, SP 05508-000, Brazil
| | - Eliana H Akamine
- Departamento de Farmacologia, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo, SP 05508-000, Brazil
| | - Luiz A Baccala
- Departamento de Engenharia de Telecomunicacoes e Controle, Escola Politecnica, Universidade de Sao Paulo, Sao Paulo, SP 05508-900, Brazil
| | - André Fujita
- Departamento de Estatistica, Instituto de Matematica e Estatistica, Universidade de Sao Paulo, Sao Paulo, SP 05508-090, Brazil
| | - Alexandre A Steiner
- Departamento de Imunologia, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Av. Prof. Lineu Prestes, 1730, Sao Paulo, SP 05508-000, Brazil
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Machado SA, Pasquarelli-do-Nascimento G, da Silva DS, Farias GR, de Oliveira Santos I, Baptista LB, Magalhães KG. Browning of the white adipose tissue regulation: new insights into nutritional and metabolic relevance in health and diseases. Nutr Metab (Lond) 2022; 19:61. [PMID: 36068578 PMCID: PMC9446768 DOI: 10.1186/s12986-022-00694-0] [Citation(s) in RCA: 52] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Accepted: 08/19/2022] [Indexed: 12/11/2022] Open
Abstract
Adipose tissues are dynamic tissues that play crucial physiological roles in maintaining health and homeostasis. Although white adipose tissue and brown adipose tissue are currently considered key endocrine organs, they differ functionally and morphologically. The existence of the beige or brite adipocytes, cells displaying intermediary characteristics between white and brown adipocytes, illustrates the plastic nature of the adipose tissue. These cells are generated through white adipose tissue browning, a process associated with augmented non-shivering thermogenesis and metabolic capacity. This process involves the upregulation of the uncoupling protein 1, a molecule that uncouples the respiratory chain from Adenosine triphosphate synthesis, producing heat. β-3 adrenergic receptor system is one important mediator of white adipose tissue browning, during cold exposure. Surprisingly, hyperthermia may also induce beige activation and white adipose tissue beiging. Physical exercising copes with increased levels of specific molecules, including Beta-Aminoisobutyric acid, irisin, and Fibroblast growth factor 21 (FGF21), which induce adipose tissue browning. FGF21 is a stress-responsive hormone that interacts with beta-klotho. The central roles played by hormones in the browning process highlight the relevance of the individual lifestyle, including circadian rhythm and diet. Circadian rhythm involves the sleep-wake cycle and is regulated by melatonin, a hormone associated with UCP1 level upregulation. In contrast to the pro-inflammatory and adipose tissue disrupting effects of the western diet, specific food items, including capsaicin and n-3 polyunsaturated fatty acids, and dietary interventions such as calorie restriction and intermittent fasting, favor white adipose tissue browning and metabolic efficiency. The intestinal microbiome has also been pictured as a key factor in regulating white tissue browning, as it modulates bile acid levels, important molecules for the thermogenic program activation. During embryogenesis, in which adipose tissue formation is affected by Bone morphogenetic proteins that regulate gene expression, the stimuli herein discussed influence an orchestra of gene expression regulators, including a plethora of transcription factors, and chromatin remodeling enzymes, and non-coding RNAs. Considering the detrimental effects of adipose tissue browning and the disparities between adipose tissue characteristics in mice and humans, further efforts will benefit a better understanding of adipose tissue plasticity biology and its applicability to managing the overwhelming burden of several chronic diseases.
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Affiliation(s)
- Sabrina Azevedo Machado
- Laboratory of Immunology and Inflammation, Department of Cell Biology, University of Brasilia, Brasília, DF, Brazil
| | | | - Debora Santos da Silva
- Laboratory of Immunology and Inflammation, Department of Cell Biology, University of Brasilia, Brasília, DF, Brazil
| | - Gabriel Ribeiro Farias
- Laboratory of Immunology and Inflammation, Department of Cell Biology, University of Brasilia, Brasília, DF, Brazil
| | - Igor de Oliveira Santos
- Laboratory of Immunology and Inflammation, Department of Cell Biology, University of Brasilia, Brasília, DF, Brazil
| | - Luana Borges Baptista
- Laboratory of Immunology and Inflammation, Department of Cell Biology, University of Brasilia, Brasília, DF, Brazil
| | - Kelly Grace Magalhães
- Laboratory of Immunology and Inflammation, Department of Cell Biology, University of Brasilia, Brasília, DF, Brazil.
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Yu X, Hussein S, Li L, Liu Q, Ban Z, Jiang H. Effect of Dihydroquercetin on Energy Metabolism in LPS-Induced Inflammatory Mice. BIOMED RESEARCH INTERNATIONAL 2022; 2022:6491771. [PMID: 35832840 PMCID: PMC9273438 DOI: 10.1155/2022/6491771] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/14/2022] [Revised: 06/02/2022] [Accepted: 06/07/2022] [Indexed: 12/04/2022]
Abstract
This study investigated the effects and alterations of dihydroquercetin on the growth performance, nutriment metabolism, antioxidant and immune function, and energy substrate utilization in lipopolysaccharide-challenged mice. A total of 0, 50, and 200 mg/kg of dihydroquercetin were intragastrically administered once a day for 21 days. After the pretreatment with dihydroquercetin, each group was subjected to a lipopolysaccharide challenge (except for the control group). After lipopolysaccharide injection, food intake, body weight, metabolic indexes of blood and liver nutrients, blood inflammatory factors, and liver oxidative stress indexes were measured at 6, 12, 24, and 48 h, respectively. Indirect calorimetry analysis was performed by respiratory gas analysis for 48 h to calculate the energy substrate metabolism of carbohydrate, fat, and protein. Urinary nitrogen excretion was measured to evaluate the urinary protein metabolism to calculate the substrate utilization. The results showed that dihydroquercetin pretreatment can significantly increase the weight gain and average food intake and decrease the mortality rate in lipopolysaccharide-induced inflammation mice. Furthermore, dihydroquercetin pretreatment can alleviate the negative effects of lipopolysaccharides by increasing levels of superoxide dismutase and glutathione peroxidase and by decreasing the malondialdehyde and serum inflammatory cytokines (interleukin-1β, nuclear factor κB, and interleukin-6). Dihydroquercetin pretreatment also can relieve nutrient metabolic disorder by increasing blood glucose, serum total protein, and liver glycogen levels and reducing serum and liver triglycerides, serum cholesterol, serum lactate dehydrogenase, and serum urea nitrogen levels. Meanwhile, it increases the relative utilization of carbohydrate, reducing relative utilization of protein and lipid, alleviating the change in energy metabolism pattern from glucose-predominant to lipid-predominant caused by lipopolysaccharide stimulation. In addition, the degree of metabolic pattern transformation depends on the dose of dihydroquercetin supplement. Finally, according to principal component analysis, we found that the inflammation was strongest in the mice at 24 h and was subsequently relieved in the LPS-stimulated group, whereas in the dihydroquercetin-pretreated group, the inflammation was initially relieved. To summarize, dihydroquercetin pretreatment can improve energy metabolism disorder and attenuate the negative effects of lipopolysaccharide challenge in mice from the initial stage of inflammation.
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Affiliation(s)
- Xiaoying Yu
- Department of Animal Science and Technology, Jilin Agricultural University, Jilin Province, Changchun, China 130118
| | - Saddam Hussein
- Department of Animal Science and Technology, Jilin Agricultural University, Jilin Province, Changchun, China 130118
| | - Lijia Li
- Jilin Academy of Agricultural Sciences, No. 1363 Shengtai Street, Changchun City, Jilin Province, China 1300119
| | - Qingyu Liu
- Jilin Academy of Agricultural Sciences, No. 1363 Shengtai Street, Changchun City, Jilin Province, China 1300119
| | - Zhibin Ban
- Jilin Academy of Agricultural Sciences, No. 1363 Shengtai Street, Changchun City, Jilin Province, China 1300119
| | - Hailong Jiang
- Department of Animal Science and Technology, Jilin Agricultural University, Jilin Province, Changchun, China 130118
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Harmon MBA, Scicluna BP, Wiewel MA, Schultz MJ, Horn J, Cremer OL, Poll T, Joost Wiersinga W, Juffermans NP, Beer FM, Bos LD, Glas GJ, Horn J, Hoogendijk AJ, Hooijdonk RT, Huson MA, Poll T, Scicluna B, Schouten LR, Schultz MJ, Straat M, van Vught LA, Wieske L, Wiewel MA, Witteveen E, Bonten MJ, Cremer OL, Frencken JF, Groep K, Klein Klouwenberg PM, Koster–Brouwer ME, Ong DS, Varkila MR, Verboom DM. Patients with hypothermic sepsis have a unique gene expression profile compared to patients with fever and sepsis. J Cell Mol Med 2022; 26:1896-1904. [PMID: 35934940 PMCID: PMC8980902 DOI: 10.1111/jcmm.17156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 09/13/2021] [Accepted: 11/25/2021] [Indexed: 11/30/2022] Open
Abstract
The pathophysiology of hypothermia during sepsis is unclear. Using genomic profiling of blood leukocytes, we aimed to determine if hypothermia is associated with a different gene expression profile compared to fever during sepsis. Patients with sepsis and either hypothermia or fever within 24 hours after ICU admission were included in the study (n = 168). Hypothermia was defined as body temperature below 36 °C. Fever was defined as body temperature equal to or above 38.3°C. We compared blood gene expression (whole‐genome transcriptome in leukocytes) in hypothermic septic compared to febrile septic patients in an unmatched analysis and matched for APACHE IV score and the presence of shock. In total, 67 septic patients were hypothermic and 101 patients were febrile. Hypothermia was associated with a distinct gene expression profile in both unmatched and matched analyses. There were significant differences related to the up‐ and downregulation of canonical signalling pathways. In the matched analysis, the top upregulated gene was cold‐inducible mRNA binding protein (CIRBP) which plays a role in cold‐induced suppression of cell proliferation. In addition, we found three signalling pathways significantly upregulated in hypothermic patients compared to febrile patients; tryptophan degradation X, phenylalanine degradation IV and putrescine degradation III. In conclusion, there are distinct signalling pathways and genes associated with hypothermia, including tryptophan degradation and CIRBP expression, providing a possible link to the modulation of body temperature and early immunosuppression. Future studies may focus on the canonical signalling pathways presented in this paper to further investigate spontaneous hypothermia in sepsis.
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Affiliation(s)
- Matthew B. A. Harmon
- Department of Intensive Care Amsterdam University Medical Centers location Academic Medical Centre University of Amsterdam Amsterdam The Netherlands
- Laboratory of Experimental Intensive Care and Anesthesiology Amsterdam University Medical Centers location Academic Medical Centre University of Amsterdam Amsterdam The Netherlands
| | - Brendon P. Scicluna
- Center for Experimental & Molecular Medicine Amsterdam University Medical Centers location Academic Medical Center University of Amsterdam Amsterdam The Netherlands
| | - Maryse A. Wiewel
- Center for Experimental & Molecular Medicine Amsterdam University Medical Centers location Academic Medical Center University of Amsterdam Amsterdam The Netherlands
| | - Marcus J. Schultz
- Department of Intensive Care Amsterdam University Medical Centers location Academic Medical Centre University of Amsterdam Amsterdam The Netherlands
- Laboratory of Experimental Intensive Care and Anesthesiology Amsterdam University Medical Centers location Academic Medical Centre University of Amsterdam Amsterdam The Netherlands
- Mahidol Oxford Research Unit Mahidol University Bangkok Thailand
- Nuffield Department of Medicine University of Oxford Oxford UK
| | - Janneke Horn
- Department of Intensive Care Amsterdam University Medical Centers location Academic Medical Centre University of Amsterdam Amsterdam The Netherlands
- Laboratory of Experimental Intensive Care and Anesthesiology Amsterdam University Medical Centers location Academic Medical Centre University of Amsterdam Amsterdam The Netherlands
| | - Olaf L. Cremer
- Department of Intensive Care Medicine University Medical Center Utrecht Utrecht The Netherlands
| | - Tom Poll
- Center for Experimental & Molecular Medicine Amsterdam University Medical Centers location Academic Medical Center University of Amsterdam Amsterdam The Netherlands
| | - W. Joost Wiersinga
- Center for Experimental & Molecular Medicine Amsterdam University Medical Centers location Academic Medical Center University of Amsterdam Amsterdam The Netherlands
| | - Nicole P. Juffermans
- Department of Intensive Care Amsterdam University Medical Centers location Academic Medical Centre University of Amsterdam Amsterdam The Netherlands
- Laboratory of Experimental Intensive Care and Anesthesiology Amsterdam University Medical Centers location Academic Medical Centre University of Amsterdam Amsterdam The Netherlands
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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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Vega Custódio S, Spohr L, Pontes Bona N, de Souza AA, de Moraes Meine B, Keske S, Pereira Luduvico K, Lopez Alvez F, Maria Spanevello R, Moro Stefanello F, Sandrielly Pereira Soares M. Effect of blueberry (Vaccinium virgatum) extract on depressive-like behavior and metabolic serum alterations in lipopolysaccharide-challenged mice. J Food Biochem 2021; 45:e13920. [PMID: 34510463 DOI: 10.1111/jfbc.13920] [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: 02/15/2021] [Revised: 08/03/2021] [Accepted: 08/19/2021] [Indexed: 12/23/2022]
Abstract
In the present study, we aimed to investigate the protective effect of blueberry extract on behavioral, biochemical, and morphological changes in an experimental model of lipopolysaccharide (LPS)-induced depressive behavior. Male Swiss mice were pretreated with the vehicle, fluoxetine (20 mg/kg), or Vaccinium virgatum extract (100 mg/kg and 200 mg/kg) for seven days. On day 7, the animals were administered an LPS injection (0.83 mg/kg) or vehicle. Pretreatment with blueberry extract prevented LPS-induced depressive-like behavior. Moreover, LPS increased serum levels of total cholesterol; however, V. virgatum did not prevent the increase in total cholesterol levels. Furthermore, the extract prevented the LPS-induced elevation in serum reactive oxygen species. Also, V. virgatum extract increased the HDL cholesterol levels. Additionally, this extract prevented the LPS-induced decrease in glucose levels and serum adenosine deaminase activity. Collectively, V. virgatum extract has a potential protective effect against changes similar to those observed in patients with depression. PRACTICAL APPLICATIONS: Vaccinium virgatum, popularly known as blueberry, has been effective in preventing or treating neuropsychiatric diseases owing to its antioxidant, anti-inflammatory, and neuroprotective properties. Fluoxetine is a known drug used to treat depression; however, its adverse effects result in therapeutic non-adherence. Thus, the search for new natural compounds possessing antidepressant activities while lacking adverse effects is crucial for identifying novel therapeutic alternatives against depression.
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Affiliation(s)
- Solange Vega Custódio
- Laboratório de Neuroquímica, Inflamação e Câncer, Centro de Ciências Químicas, Farmacêuticas e de Alimentos, Universidade Federal de Pelotas, Pelotas, RS, Brazil
| | - Luiza Spohr
- Laboratório de Neuroquímica, Inflamação e Câncer, Centro de Ciências Químicas, Farmacêuticas e de Alimentos, Universidade Federal de Pelotas, Pelotas, RS, Brazil
| | - Natália Pontes Bona
- Laboratório de Biomarcadores, Centro de Ciências Químicas, Farmacêuticas e de Alimentos, Universidade Federal de Pelotas, Pelotas, RS, Brazil
| | - Anita Avila de Souza
- Laboratório de Neuroquímica, Inflamação e Câncer, Centro de Ciências Químicas, Farmacêuticas e de Alimentos, Universidade Federal de Pelotas, Pelotas, RS, Brazil
| | - Bernardo de Moraes Meine
- Laboratório de Biomarcadores, Centro de Ciências Químicas, Farmacêuticas e de Alimentos, Universidade Federal de Pelotas, Pelotas, RS, Brazil
| | - Sara Keske
- Laboratório de Neuroquímica, Inflamação e Câncer, Centro de Ciências Químicas, Farmacêuticas e de Alimentos, Universidade Federal de Pelotas, Pelotas, RS, Brazil
| | - Karina Pereira Luduvico
- Laboratório de Biomarcadores, Centro de Ciências Químicas, Farmacêuticas e de Alimentos, Universidade Federal de Pelotas, Pelotas, RS, Brazil
| | - Fernando Lopez Alvez
- Laboratório de Neuroquímica, Inflamação e Câncer, Centro de Ciências Químicas, Farmacêuticas e de Alimentos, Universidade Federal de Pelotas, Pelotas, RS, Brazil
| | - Roselia Maria Spanevello
- Laboratório de Neuroquímica, Inflamação e Câncer, Centro de Ciências Químicas, Farmacêuticas e de Alimentos, Universidade Federal de Pelotas, Pelotas, RS, Brazil
| | - Francieli Moro Stefanello
- Laboratório de Biomarcadores, Centro de Ciências Químicas, Farmacêuticas e de Alimentos, Universidade Federal de Pelotas, Pelotas, RS, Brazil
| | - Mayara Sandrielly Pereira Soares
- Laboratório de Neuroquímica, Inflamação e Câncer, Centro de Ciências Químicas, Farmacêuticas e de Alimentos, Universidade Federal de Pelotas, Pelotas, RS, Brazil
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Alberca RW, Gomes E, Moretti EH, Russo M, Steiner AA. Naturally occurring hypothermia promotes survival in severe anaphylaxis. Immunol Lett 2021; 237:27-32. [PMID: 34245741 DOI: 10.1016/j.imlet.2021.07.002] [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: 05/11/2021] [Revised: 06/30/2021] [Accepted: 07/01/2021] [Indexed: 11/24/2022]
Abstract
Although hypothermia has received substantial attention as an indicator of severity in anaphylaxis, it has been neglected from the perspective of whether it could act as a disease-modifying factor in this condition. Here, the impact of naturally occurring (spontaneous) hypothermia on anaphylaxis was evaluated in a murine model of ovalbumin (OVA)-induced allergy. Nonextreme changes in the ambient temperature (Ta) were used to modulate the magnitude of spontaneous hypothermia. At a Ta of 24°C, challenge with OVA intraperitoneally or intravenously resulted in a rapid, transient fall in body core temperature, which reached its nadir 4-6°C below baseline in 30 min. This hypothermic response was largely attenuated when the mice were kept at a Ta of 34°C. The Ta-dependent attenuation of hypothermia resulted in a survival rate of only 30%, as opposed to survival of 100% in the condition that favored the development of hypothermia. The protective effect of hypothermia did not involve changes in the rate of mast cell degranulation, as assessed by the concentration of mast cell protease-1 in bodily fluids. On the other hand, hypothermia improved oxygenation of the brain and kidneys, as indicated by higher NAD+/NADH ratios. Therefore, it is plausible to propose that naturally occurring hypothermia makes organs more resistant to the anaphylactic insult.
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Affiliation(s)
- Ricardo W Alberca
- Departamento de Imunologia, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo, SP 05508, Brazil
| | - Eliane Gomes
- Departamento de Imunologia, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo, SP 05508, Brazil
| | - Eduardo H Moretti
- Departamento de Imunologia, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo, SP 05508, Brazil
| | - Momtchilo Russo
- Departamento de Imunologia, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo, SP 05508, Brazil
| | - Alexandre A Steiner
- Departamento de Imunologia, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo, SP 05508, Brazil.
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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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11
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Martínez BA, Hoyle RG, Yeudall S, Granade ME, Harris TE, Castle JD, Leitinger N, Bland ML. Innate immune signaling in Drosophila shifts anabolic lipid metabolism from triglyceride storage to phospholipid synthesis to support immune function. PLoS Genet 2020; 16:e1009192. [PMID: 33227003 PMCID: PMC7721134 DOI: 10.1371/journal.pgen.1009192] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 12/07/2020] [Accepted: 10/13/2020] [Indexed: 02/07/2023] Open
Abstract
During infection, cellular resources are allocated toward the metabolically-demanding processes of synthesizing and secreting effector proteins that neutralize and kill invading pathogens. In Drosophila, these effectors are antimicrobial peptides (AMPs) that are produced in the fat body, an organ that also serves as a major lipid storage depot. Here we asked how activation of Toll signaling in the larval fat body perturbs lipid homeostasis to understand how cells meet the metabolic demands of the immune response. We find that genetic or physiological activation of fat body Toll signaling leads to a tissue-autonomous reduction in triglyceride storage that is paralleled by decreased transcript levels of the DGAT homolog midway, which carries out the final step of triglyceride synthesis. In contrast, Kennedy pathway enzymes that synthesize membrane phospholipids are induced. Mass spectrometry analysis revealed elevated levels of major phosphatidylcholine and phosphatidylethanolamine species in fat bodies with active Toll signaling. The ER stress mediator Xbp1 contributed to the Toll-dependent induction of Kennedy pathway enzymes, which was blunted by deleting AMP genes, thereby reducing secretory demand elicited by Toll activation. Consistent with ER stress induction, ER volume is expanded in fat body cells with active Toll signaling, as determined by transmission electron microscopy. A major functional consequence of reduced Kennedy pathway induction is an impaired immune response to bacterial infection. Our results establish that Toll signaling induces a shift in anabolic lipid metabolism to favor phospholipid synthesis and ER expansion that may serve the immediate demand for AMP synthesis and secretion but with the long-term consequence of insufficient nutrient storage.
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Affiliation(s)
- Brittany A. Martínez
- Biomedical Sciences Graduate Program, University of Virginia, Charlottesville, VA, United States of America
- Department of Pharmacology, University of Virginia, Charlottesville, VA, United States of America
| | - Rosalie G. Hoyle
- Department of Pharmacology, University of Virginia, Charlottesville, VA, United States of America
| | - Scott Yeudall
- Department of Pharmacology, University of Virginia, Charlottesville, VA, United States of America
- Medical Scientist Training Program, University of Virginia, Charlottesville, VA, United States of America
| | - Mitchell E. Granade
- Biomedical Sciences Graduate Program, University of Virginia, Charlottesville, VA, United States of America
- Department of Pharmacology, University of Virginia, Charlottesville, VA, United States of America
| | - Thurl E. Harris
- Biomedical Sciences Graduate Program, University of Virginia, Charlottesville, VA, United States of America
- Department of Pharmacology, University of Virginia, Charlottesville, VA, United States of America
| | - J. David Castle
- Department of Cell Biology, University of Virginia, Charlottesville, VA, United States of America
| | - Norbert Leitinger
- Biomedical Sciences Graduate Program, University of Virginia, Charlottesville, VA, United States of America
- Department of Pharmacology, University of Virginia, Charlottesville, VA, United States of America
| | - Michelle L. Bland
- Biomedical Sciences Graduate Program, University of Virginia, Charlottesville, VA, United States of America
- Department of Pharmacology, University of Virginia, Charlottesville, VA, United States of America
- * E-mail:
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Amaral-Silva L, Tazawa H, Bícego KC, Burggren WW. Metabolic and Hematological Responses to Endotoxin-Induced Inflammation in Chicks Experiencing Embryonic 2,3,7,8-Tetrachlorodibenzodioxin Exposure. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2020; 39:2208-2220. [PMID: 32725906 DOI: 10.1002/etc.4832] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 06/10/2020] [Accepted: 07/27/2020] [Indexed: 06/11/2023]
Abstract
Dioxin exposure during bird embryonic development disrupts immunity as well as mechanisms involved in energy metabolism, potentially affecting negatively acute-phase responses to pathogens. Thus, we hypothesized that embryonic exposure to 2,3,7,8-tetrachlorodibenzodioxin (TCDD) changes the metabolism and blood physiology of domestic chicks, affecting their physiological competence for responding to immune challenges. To test this hypothesis, we injected doses of 0, 1.5, and 3 ng TCDD/egg (based on survival experiments) on embryonic day 4 and then measured O2 consumption and CO2 production for metabolic rate, ventilation, and body temperature (TB ) in 5-d-old chicks. Then, chicks were injected with lipopolysaccharide (LPS, endotoxin) or saline prior to repeating the physiological measurements. A second chick group exposed to identical TCDD and LPS treatments had blood partial pressure of oxygen, partial pressure of carbon dioxide, pH, bicarbonate concentration, lactate concentration, osmolality, hemoglobin concentration, red blood cell concentration, and hematocrit, as well as TB , analyzed at 1 and 5 h after LPS injection. Metabolism in chicks embryonically exposed to 1.5 and 3 ng TCDD/egg was up to 37% higher, whereas body mass of chicks exposed to 3 ng TCDD/egg was approximately 6% lower. Chicks embryonically exposed to 3 ng TCDD/egg challenged with LPS showed a relative persistent hypometabolism accompanied by elimination of the normal hematological and osmotic responses to LPS. We conclude that embryonic exposure to TCDD affects posthatching metabolism as well as impairs metabolic, hematological, and osmotic responses to LPS. Environ Toxicol Chem 2020;39:2208-2220. © 2020 SETAC.
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Affiliation(s)
- Lara Amaral-Silva
- Department of Animal Morphology and Physiology, College of Agricultural and Veterinary Sciences, São Paulo State University, Jaboticabal, São Paulo, Brazil
- Department of Biological Sciences, University of North Texas, Denton, Texas, USA
| | - Hiroshi Tazawa
- Department of Biological Sciences, University of North Texas, Denton, Texas, USA
| | - Kênia Cardoso Bícego
- Department of Animal Morphology and Physiology, College of Agricultural and Veterinary Sciences, São Paulo State University, Jaboticabal, São Paulo, Brazil
| | - Warren W Burggren
- Department of Biological Sciences, University of North Texas, Denton, Texas, USA
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Komegae EN, Fonseca MT, Steiner AA. Diet-induced obesity attenuates the hypothermic response to lipopolysaccharide independently of TNF-α production. Temperature (Austin) 2020; 7:270-276. [PMID: 33123620 DOI: 10.1080/23328940.2019.1707155] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
Life-threatening infections (sepsis) are usually associated with co-morbidities, among which obesity deserves attention. Here, we evaluated whether and how obesity affects the switch from fever to hypothermia that occurs in the most severe cases of sepsis, which is thought to provide physiological support for a change in host defense strategy from resistance to tolerance. Obesity was induced by keeping rats on a high-fat diet for 32-34 weeks. The hypothermia induced by a high dose of bacterial lipopolysaccharide (LPS, 300 μg/animal, i.a.) was attenuated in the obese rats, as compared to their low-fat diet counterparts. Surprisingly, such attenuation occurred in spite of an enhancement in the circulating level of TNF-α, the most renowned mediator of LPS-induced hypothermia. Hence, it seems that factors counteracting not the production, but rather the action of TNF-α are at play in rats with diet-induced obesity. One of these factors might be IL-1β, a febrigenic mediator that also had its circulating levels augmented in the obese rats challenged with LPS. Taken together with previous reports of diet-induced obesity enhancing the fever induced by lower doses of LPS, the results of the present study indicate that obesity biases host defense toward a fever/resistance strategy, in lieu of a hypothermia/tolerance strategy.
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Affiliation(s)
- Evilin N Komegae
- Neuroimmunology of Sepsis Laboratory, Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Monique T Fonseca
- Neuroimmunology of Sepsis Laboratory, Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Alexandre A Steiner
- Neuroimmunology of Sepsis Laboratory, Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
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14
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Lang GP, Ndongson-Dongmo B, Lajqi T, Brodhun M, Han Y, Wetzker R, Frasch MG, Bauer R. Impact of ambient temperature on inflammation-induced encephalopathy in endotoxemic mice-role of phosphoinositide 3-kinase gamma. J Neuroinflammation 2020; 17:292. [PMID: 33028343 PMCID: PMC7541275 DOI: 10.1186/s12974-020-01954-7] [Citation(s) in RCA: 8] [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: 04/04/2020] [Accepted: 09/16/2020] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Sepsis-associated encephalopathy (SAE) is an early and frequent event of infection-induced systemic inflammatory response syndrome. Phosphoinositide 3-kinase γ (PI3Kγ) is linked to neuroinflammation and inflammation-related microglial activity. In homeotherms, variations in ambient temperature (Ta) outside the thermoneutral zone lead to thermoregulatory responses, mainly driven by a gradually increasing sympathetic activity, and may affect disease severity. We hypothesized that thermoregulatory response to hypothermia (reduced Ta) aggravates SAE in PI3Kγ-dependent manner. METHODS Experiments were performed in wild-type, PI3Kγ knockout, and PI3Kγ kinase-dead mice, which were kept at neutral (30 ± 0.5 °C) or moderately lowered (26 ± 0.5 °C) Ta. Mice were exposed to lipopolysaccharide (LPS, 10 μg/g, from Escherichia coli serotype 055:B5, single intraperitoneal injection)-evoked systemic inflammatory response (SIR) and monitored 24 h for thermoregulatory response and blood-brain barrier integrity. Primary microglial cells and brain tissue derived from treated mice were analyzed for inflammatory responses and related cell functions. Comparisons between groups were made with one-way or two-way analysis of variance, as appropriate. Post hoc comparisons were made with the Holm-Sidak test or t tests with Bonferroni's correction for adjustments of multiple comparisons. Data not following normal distribution was tested with Kruskal-Wallis test followed by Dunn's multiple comparisons test. RESULTS We show that a moderate reduction of ambient temperature triggers enhanced hypothermia of mice undergoing LPS-induced systemic inflammation by aggravated SAE. PI3Kγ deficiency enhances blood-brain barrier injury and upregulation of matrix metalloproteinases (MMPs) as well as an impaired microglial phagocytic activity. CONCLUSIONS Thermoregulatory adaptation in response to ambient temperatures below the thermoneutral range exacerbates LPS-induced blood-brain barrier injury and neuroinflammation. PI3Kγ serves a protective role in suppressing release of MMPs, maintaining microglial motility and reinforcing phagocytosis leading to improved brain tissue integrity. Thus, preclinical research targeting severe brain inflammation responses is seriously biased when basic physiological prerequisites of mammal species such as preferred ambient temperature are ignored.
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Affiliation(s)
- Guang-Ping Lang
- Institute of Molecular Cell Biology, Jena University Hospital, Friedrich Schiller University, Hans-Knöll-Straße 2, D-07745 Jena, Germany
- Joint International Research Laboratory of Ethnomedicine and Key Laboratory of Basic Pharmacology of Ministry of Education, Zunyi Medical University, Zunyi, 563006 China
| | - Bernadin Ndongson-Dongmo
- Institute of Molecular Cell Biology, Jena University Hospital, Friedrich Schiller University, Hans-Knöll-Straße 2, D-07745 Jena, Germany
- Department of Pharmacology, University of Oslo and Oslo University Hospital, Oslo, Norway
| | - Trim Lajqi
- Institute of Molecular Cell Biology, Jena University Hospital, Friedrich Schiller University, Hans-Knöll-Straße 2, D-07745 Jena, Germany
- Department of Neonatology, University Children’s Hospital, Heidelberg, Germany
| | - Michael Brodhun
- Department of Pathology, Helios-Klinikum Erfurt, Erfurt, Germany
| | - Yingying Han
- Institute of Biochemistry I, Faculty of Medicine, Goethe-University Frankfurt, 60590 Frankfurt, Germany
| | - Reinhard Wetzker
- Department of Anesthesiology and Intensive Care Medicine, Jena University Hospital, Friedrich Schiller University, Jena, Germany
| | | | - Reinhard Bauer
- Institute of Molecular Cell Biology, Jena University Hospital, Friedrich Schiller University, Hans-Knöll-Straße 2, D-07745 Jena, Germany
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15
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Landes J, Pavard S, Henry PY, Terrien J. Flexibility Is Costly: Hidden Physiological Damage From Seasonal Phenotypic Transitions in Heterothermic Species. Front Physiol 2020; 11:985. [PMID: 32903301 PMCID: PMC7434983 DOI: 10.3389/fphys.2020.00985] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Accepted: 07/20/2020] [Indexed: 12/20/2022] Open
Abstract
Heterothermy allows organisms to cope with fluctuating environmental conditions. The use of regulated hypometabolism allows seasonal heterothermic species to cope with annual resource shortages and thus to maximize survival during the unfavorable season. This comes with deep physiological remodeling at each seasonal transition to allow the organism to adjust to the changing environment. In the wild, this adaptation is highly beneficial and largely overcomes potential costs. However, researchers recently proposed that it might also generate both ecological and physiological costs for the organism. Here, we propose new perspectives to be considered when analyzing adaptation to seasonality, in particular considering these costs. We propose a list of putative costs, including DNA damage, inflammatory response to fat load, brain and cognitive defects, digestive malfunction and immunodeficiency, that should receive more attention in future research on physiological seasonality. These costs may only be marginal at each transition event but accumulate over time and therefore emerge with age. In this context, studies in captivity, where we have access to aging individuals with limited extrinsic mortality (e.g., predation), could be highly valuable to experimentally assess the costs of physiological flexibility. Finally, we offer new perspectives, which should be included in demographic models, on how the adaptive value of physiological flexibility could be altered in the future in the context of global warming.
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Affiliation(s)
- Julie Landes
- Unité Mécanismes Adaptatifs et Evolution (MECADEV), UMR 7179, CNRS, Muséum National d'Histoire Naturelle, Brunoy, France.,Unité Eco-anthropologie (EA), Muséum National d'Histoire Naturelle, CNRS, Université de Paris, Paris, France
| | - Samuel Pavard
- Unité Eco-anthropologie (EA), Muséum National d'Histoire Naturelle, CNRS, Université de Paris, Paris, France
| | - Pierre-Yves Henry
- Unité Mécanismes Adaptatifs et Evolution (MECADEV), UMR 7179, CNRS, Muséum National d'Histoire Naturelle, Brunoy, France
| | - Jérémy Terrien
- Unité Mécanismes Adaptatifs et Evolution (MECADEV), UMR 7179, CNRS, Muséum National d'Histoire Naturelle, Brunoy, France
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Association of triage hypothermia with in-hospital mortality among patients in the emergency department with suspected sepsis. J Crit Care 2020; 60:27-31. [PMID: 32731103 DOI: 10.1016/j.jcrc.2020.07.011] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 07/11/2020] [Accepted: 07/11/2020] [Indexed: 01/20/2023]
Abstract
PURPOSE To identify if triage hypothermia (<36.0 °C) among emergency department (ED) encounters with sepsis are independently associated with mortality. METHODS We analyzed data from a multi-stage probability sample survey of visits to United States EDs between 2007 and 2015, using two inclusion approaches: an explicit definition based on diagnosis codes for sepsis and a severe sepsis definition, combining evidence of infection with organ dysfunction. We used multivariable regression to determine an association between hypothermia and in-hospital mortality. RESULTS Of 1.2 billion ED encounters (95% confidence interval [CI] 1.0-1.3 billion), 3.1 million (95% CI 2.7-3.5 million) met the explicit sepsis definition; 7.4% (95% CI 75.2-9.7%) had triage hypothermia. The adjusted odds ratio (aOR) for hypothermia for in-hospital mortality was 6.82 (95% CI 3.08-15.22). The severe sepsis definition identified 3.5 million (95% 3.1-4.0 million) encounters; 30.3% (95% CI 25.0-34.6%) had triage hypothermia. The aOR for hypothermia with mortality was 4.08 (95% CI 2.09-7.95). Depending on sepsis definition, 78.1-84.4% had other systemic inflammatory response syndrome vital sign abnormalities. CONCLUSION Up to one in three patients with sepsis have triage hypothermia, which is independently associated with mortality. 10-20% of patients with hypothermic sepsis do not have other vital sign abnormalities.
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Yang H, Du L, Zhang Z. Potential biomarkers in septic shock besides lactate. Exp Biol Med (Maywood) 2020; 245:1066-1072. [PMID: 32276542 DOI: 10.1177/1535370220919076] [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] [Indexed: 12/17/2022] Open
Abstract
IMPACT STATEMENT Elevated lactate has been commonly considered as a biomarker and a useful prognostic tool for resuscitation in septic shock, facilitating physician more rapid intervention and treatment. However, it can be initiated by hypoxia, but persistent hyperlactatemia may not represent persistent hypoxia only. In the article, it is the first time to review potential biomarkers in septic shock from the point of view of energy metabolism including intermediates of TCA cycle, MAS, the NAD+/NADH ratio, NAD+, NADH, malate, and MDH. And the combination of lactate and MDH is also proposed in septic shock for the first time, as MDH in cytoplasm and mitochondria participates in both MAS and TCA cycle for ATP generation. Its feasibility in clinic has been analyzed at the end, although related research is still limited. It is reasonable the combination of lactate and MDH will be more comprehensive to reflex hypoxia in septic shock.
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Affiliation(s)
- Hang Yang
- Department of Emergency Medicine, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310000, China
| | - Linlin Du
- Department of Critical Care Medicine, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310000, China
| | - Zhaocai Zhang
- Department of Critical Care Medicine, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310000, China
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Asisipo M, Gwladys NT, Musa MV. Effect of a novel prolonged febrile seizure model on GABA associated ion channels. Metab Brain Dis 2020; 35:441-449. [PMID: 31691144 DOI: 10.1007/s11011-019-00492-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Accepted: 09/10/2019] [Indexed: 11/25/2022]
Abstract
Prolonged febrile seizures are usually modelled in animals using hyperthermia as an inducer. In this study, a modified simple febrile seizure model using a combination of lipopolysaccharide (LPS) and kainic acid (KA) was used to develop a prolonged febrile seizure animal model, which we used to assess effects on the expression of the sodium- potassium-chloride cotransporter 1 (NKCC1) and potassium-chloride cotransporter 2 (KCC2) and their possible role in seizure exacerbation. At post-natal day (PND) 14, rat pups were divided into a saline (S), simple febrile seizure (FSA-), prolonged febrile seizure (FSB-), saline A (SA+) and saline B (SB+) groups. SA+ and SB+ groups received different concentrations of KA (1.75 mg/kg, 1.83 μg/kg respectively) but no LPS. Changes in temperature, seizure activity and duration were recorded. Gene and protein expression of NKCC1, KCC2 and KCC2 phosphorylated serine (KCC2 ser) 940 were measured 1 h post seizure termination and on PND 15 using RT- PCR and western blot. There was an initial increase in temperature that was immediately followed by a temperature decrease and an increase in seizure severity and duration in the FSB- group. There was a decrease in KCC2 ser 940 protein expression. NKCC1 protein expression was increased in both FS groups suggesting decreased GABA receptor functionality. Therefore, the novel FSB- model resulted in more severe and sustained seizure activity by altering cotransporter gene and protein expression. This suggests that this model can be used to mimic prolonged febrile seizures and hence can be used to investigate the physiological changes accompanying this condition.
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Affiliation(s)
- Mohamed Asisipo
- Discipline of Human Physiology, School of Laboratory Medicine & Medical Sciences, College of Health Sciences, University of KwaZulu-Natal, Durban, 4000, South Africa
| | - Ngoupaye Temkou Gwladys
- Department of Animal Biology, Faculty of Science, University of Dschang, P.O. Box 67, Dschang, Cameroon.
- Discipline of Human Physiology, School of Laboratory Medicine & Medical Sciences, College of Health Sciences, University of KwaZulu-Natal, Durban, 4000, South Africa.
| | - Mabandla Vuyisile Musa
- Discipline of Human Physiology, School of Laboratory Medicine & Medical Sciences, College of Health Sciences, University of KwaZulu-Natal, Durban, 4000, South Africa
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Steiner AA, Romanovsky AA. Energy Trade-offs in Host Defense: Immunology Meets Physiology. Trends Endocrinol Metab 2019; 30:875-878. [PMID: 31668960 DOI: 10.1016/j.tem.2019.08.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Revised: 08/23/2019] [Accepted: 08/27/2019] [Indexed: 01/05/2023]
Abstract
Host defense relies not only on microbicidal mechanisms (resistance), but also on management of collateral damage (tolerance). Here, we discuss how this immunology concept converges with a physiology-born theory on the dichotomy of thermometabolic responses in infection (fever versus hypothermia), yielding a model of immunity that transcends discipline barriers.
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Affiliation(s)
- Alexandre A Steiner
- Neuroimmunology of Sepsis Laboratory, Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP 05508, Brazil.
| | - Andrej A Romanovsky
- Thermoregulation and Systemic Inflammation Laboratory (FeverLab), Trauma Research, St. Joseph's Hospital and Medical Center, Phoenix, AZ 85013, USA
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Abstract
Sepsis continues to be a major challenge for modern medicine. Several preclinical models were developed to study sepsis and each has strengths and weaknesses. The cecal slurry (CS) method is a practical alternative because it does not require surgery, and the infection can be dosed. However, one disadvantage is that the dosage must be determined for each CS preparation using survival studies. Our aim was to refine a survival protocol for the CS model by determining a premonitory humane endpoint that would reduce animal suffering. Mice become hypothermic in sepsis; therefore, we tested whether reductions in surface temperature (Ts), measured by noninvasive infrared thermometry, could predict eventual death. We injected 154 C57BL/6J mice with CS (0.9-1.8 mg/g) and periodically monitored Ts at the xiphoid process over 5 days. We used, as predictors, combinations of temperature thresholds (29°C -31°C) and times, postinjection (18-36 h). A receiver-operator curve, sensitivity, and specificity were determined. A Distress Index value was calculated for the threshold conditions. The optimum detection threshold (highest Youden index) was found at Ts ≤ 30.5°C at 24 h (90% specific, 84% sensitive). This threshold condition reduced animal suffering by 41% while providing an accurate survival rate estimate. Using this threshold, only 13 of 154 mice would have died from sepsis; 67 would have been euthanized at 24 h, and only 7 of 154 would have been euthanized unnecessarily. In conclusion, using a humane endpoint of Ts ≤ 30.5°C at 24 h accurately predicts mortality and can effectively reduce animal suffering during CS survival protocols.
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Yao W, Chen J, Wu S, Han X, Guan J, Yuan D, Cai J, Hei Z. ONO-5046 suppresses reactive oxidative species-associated formation of neutrophil extracellular traps. Life Sci 2018; 210:243-250. [DOI: 10.1016/j.lfs.2018.09.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 08/28/2018] [Accepted: 09/03/2018] [Indexed: 12/27/2022]
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Moretti EH, Ortega Chinchilla JE, Marques FS, Fernandes PAC, Gomes FR. Behavioral fever decreases metabolic response to lipopolysaccharide in yellow Cururu toads (Rhinella icterica). Physiol Behav 2018; 191:73-81. [DOI: 10.1016/j.physbeh.2018.04.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 04/05/2018] [Accepted: 04/05/2018] [Indexed: 10/17/2022]
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Garami A, Steiner AA, Romanovsky AA. Fever and hypothermia in systemic inflammation. HANDBOOK OF CLINICAL NEUROLOGY 2018; 157:565-597. [PMID: 30459026 DOI: 10.1016/b978-0-444-64074-1.00034-3] [Citation(s) in RCA: 71] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Systemic inflammation-associated syndromes (e.g., sepsis and septic shock) often have high mortality and remain a challenge in emergency medicine. Systemic inflammation is usually accompanied by changes in body temperature: fever or hypothermia. In animal studies, systemic inflammation is often modeled by administering bacterial lipopolysaccharide, which triggers autonomic and behavioral thermoeffector responses and causes either fever or hypothermia, depending on the dose and ambient temperature. Fever and hypothermia are regulated changes of body temperature, which correspond to mild and severe forms of systemic inflammation, respectively. Mediators of fever and hypothermia are called endogenous pyrogens and cryogens; they are produced when the innate immune system recognizes an infectious pathogen. Upon an inflammatory challenge, hepatic and pulmonary macrophages (and later brain endothelial cells) start to release lipid mediators, of which prostaglandin (PG) E2 plays the key role, and cytokines. Blood PGE2 enters the brain and triggers fever. At later stages of fever, PGE2 synthesized within the blood-brain barrier maintains fever. In both cases, PGE2 is synthesized by cyclooxygenase-2 and microsomal PGE2synthase-1. Mediators of hypothermia are not well established. Both fever and hypothermia are beneficial host defense responses. Based on evidence from studies in laboratory animals and clinical trials in humans, fever is beneficial for fighting mild infection. Based mainly on animal studies, hypothermia is beneficial in severe systemic inflammation and infection.
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Affiliation(s)
- Andras Garami
- Institute for Translational Medicine, Medical School, University of Pécs, Pécs, Hungary.
| | - Alexandre A Steiner
- Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Andrej A Romanovsky
- Thermoregulation and Systemic Inflammation Laboratory (FeverLab), Trauma Research, St. Joseph's Hospital and Medical Center, Phoenix, AZ, United States
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Abstract
The major symptoms of motion sickness are well known and include facial pallor, nausea and vomiting, and sweating, but it is poorly recognized that they actually reflect severely perturbed thermoregulation. Thus, the purpose of this chapter is to present and discuss existing data related to this subject. While hypothermia during seasickness was first noted nearly 150 years ago, detailed studies of this phenomenon were conducted only during the last two decades. Our own research confirmed that motion sickness-induced hypothermia is quite broadly expressed phylogenetically as, besides humans, it could be provoked in several other animals (rats, musk shrews, and mice). Evidence from human and animal experiments indicates that the physiologic mechanisms responsible for the motion sickness-induced hypothermia include cutaneous vasodilation and sweating (leading to an increase of heat loss) and reduced thermogenesis. Together, these results suggest that motion sickness triggers a highly coordinated physiologic response aiming to reduce body temperature. The chapter is concluded by presenting hypotheses of how and why motion sickness evokes this hypothermic response.
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Affiliation(s)
- Eugene Nalivaiko
- School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, NSW, Australia.
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Abstract
Accidental hypothermia causes profound changes to the body's physiology. After an initial burst of agitation (e.g., 36-37°C), vital functions will slow down with further cooling, until they vanish (e.g. <20-25°C). Thus, a deeply hypothermic person may appear dead, but may still be able to be resuscitated if treated correctly. The hospital use of minimally invasive rewarming for nonarrested, otherwise healthy patients with primary hypothermia and stable vital signs has the potential to substantially decrease morbidity and mortality for these patients. Extracorporeal life support (ECLS) has revolutionized the management of hypothermic cardiac arrest, with survival rates approaching 100%. Hypothermic patients with risk factors for imminent cardiac arrest (i.e., temperature <28°C, ventricular arrhythmia, systolic blood pressure <90 mmHg), and those who have already arrested, should be transferred directly to an ECLS center. Cardiac arrest patients should receive continuous cardiopulmonary resuscitation (CPR) during transfer. If prolonged transport is required or terrain is difficult, mechanic CPR can be helpful. Intermittent CPR may be appropriate in hypothermic arrest when continuous CPR is impossible. Modern postresuscitation care should be implemented following hypothermic arrest. Structured protocols should be in place to optimize prehospital triage, transport, and treatment as well as in-hospital management, including detailed criteria and protocols for the use of ECLS and postresuscitation care.
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Affiliation(s)
- Peter Paal
- Department of Anaesthesia and Intensive Care Medicine, Hospitallers Brothers Hospital, Salzburg, Austria.
| | - Hermann Brugger
- Institute of Mountain Emergency Medicine, EURAC Research, Bolzano, Italy
| | - Giacomo Strapazzon
- Institute of Mountain Emergency Medicine, EURAC Research, Bolzano, Italy
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Steiner AA, Flatow EA, Brito CF, Fonseca MT, Komegae EN. Respiratory gas exchange as a new aid to monitor acidosis in endotoxemic rats: relationship to metabolic fuel substrates and thermometabolic responses. Physiol Rep 2017; 5:5/1/e13100. [PMID: 28082427 PMCID: PMC5256159 DOI: 10.14814/phy2.13100] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Revised: 12/01/2016] [Accepted: 12/03/2016] [Indexed: 11/26/2022] Open
Abstract
This study introduces the respiratory exchange ratio (RER; the ratio of whole‐body CO2 production to O2 consumption) as an aid to monitor metabolic acidosis during the early phase of endotoxic shock in unanesthetized, freely moving rats. Two serotypes of lipopolysaccharide (lipopolysaccharide [LPS] O55:B5 and O127:B8) were tested at shock‐inducing doses (0.5–2 mg/kg). Phasic rises in RER were observed consistently across LPS serotypes and doses. The RER rise often exceeded the ceiling of the quotient for oxidative metabolism, and was mirrored by depletion of arterial bicarbonate and decreases in pH. It occurred independently of ventilatory adjustments. These data indicate that the rise in RER results from a nonmetabolic CO2 load produced via an acid‐induced equilibrium shift in the bicarbonate buffer. Having validated this new experimental aid, we asked whether acidosis was interconnected with the metabolic and thermal responses that accompany endotoxic shock in unanesthetized rats. Contrary to this hypothesis, however, acidosis persisted regardless of whether the ambient temperature favored or prevented downregulation of mitochondrial oxidation and regulated hypothermia. We then asked whether the substrate that fuels aerobic metabolism could be a relevant factor in LPS‐induced acidosis. Food deprivation was employed to divert metabolism away from glucose oxidation and toward fatty acid oxidation. Interestingly, this intervention attenuated the RER response to LPS by 58%, without suppressing other key aspects of systemic inflammation. We conclude that acid production in unanesthetized rats with endotoxic shock results from a phasic activation of glycolysis, which occurs independently of physiological changes in mitochondrial oxidation and body temperature.
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Affiliation(s)
- Alexandre A Steiner
- Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Elizabeth A Flatow
- Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Camila F Brito
- Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Monique T Fonseca
- Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Evilin N Komegae
- Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
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Flatow EA, Komegae EN, Fonseca MT, Brito CF, Musteata FM, Antunes-Rodrigues J, Steiner AA. Elucidating the role of leptin in systemic inflammation: a study targeting physiological leptin levels in rats and their macrophages. Am J Physiol Regul Integr Comp Physiol 2017; 313:R572-R582. [DOI: 10.1152/ajpregu.00171.2017] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Revised: 07/18/2017] [Accepted: 07/26/2017] [Indexed: 01/24/2023]
Abstract
To elucidate the role of leptin in acute systemic inflammation, we investigated how its infusion at low, physiologically relevant doses affects the responses to bacterial lipopolysaccharide (LPS) in rats subjected to 24 h of food deprivation. Leptin was infused subcutaneously (0–20 μg·kg−1·h−1) or intracerebroventricularly (0–1 μg·kg−1·h−1). Using hypothermia and hypotension as biomarkers of systemic inflammation, we identified the phase extending from 90 to 240 min post-LPS as the most susceptible to modulation by leptin. In this phase, leptin suppressed the rise in plasma TNF-α and accelerated the recoveries from hypothermia and hypotension. Suppression of TNF-α was not accompanied by changes in other cytokines or prostaglandins. Leptin suppressed TNF-α when infused peripherally but not when infused into the brain. Importantly, the leptin dose that suppressed TNF-α corresponded to the lowest dose that limited food consumption; this dose elevated plasma leptin within the physiological range (to 5.9 ng/ml). We then conducted in vitro experiments to investigate whether an action of leptin on macrophages could parallel our in vivo observations. The results revealed that, when sensitized by food deprivation, LPS-stimulated peritoneal macrophages can be inhibited by leptin at concentrations that are lower than those reported to promote cytokine release. It is concluded that physiological levels of leptin do not exert a proinflammatory effect but rather an anti-inflammatory effect involving selective suppression of TNF-α via an action outside the brain. The mechanism of this effect might involve a previously unrecognized, suppressive action of leptin on macrophage subpopulations sensitized by food deprivation, but future studies are warranted.
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Affiliation(s)
- Elizabeth A. Flatow
- Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Evilin N. Komegae
- Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Monique T. Fonseca
- Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Camila F. Brito
- Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Florin M. Musteata
- Department of Pharmaceutical Sciences, Albany College of Pharmacy and Health Sciences, Albany, New York; and
| | - José Antunes-Rodrigues
- Department of Physiology, Medical School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil
| | - Alexandre A. Steiner
- Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
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Rumbus Z, Matics R, Hegyi P, Zsiboras C, Szabo I, Illes A, Petervari E, Balasko M, Marta K, Miko A, Parniczky A, Tenk J, Rostas I, Solymar M, Garami A. Fever Is Associated with Reduced, Hypothermia with Increased Mortality in Septic Patients: A Meta-Analysis of Clinical Trials. PLoS One 2017; 12:e0170152. [PMID: 28081244 PMCID: PMC5230786 DOI: 10.1371/journal.pone.0170152] [Citation(s) in RCA: 81] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Accepted: 12/29/2016] [Indexed: 12/29/2022] Open
Abstract
Background Sepsis is usually accompanied by changes of body temperature (Tb), but whether fever and hypothermia predict mortality equally or differently is not fully clarified. We aimed to find an association between Tb and mortality in septic patients with meta-analysis of clinical trials. Methods We searched the PubMed, EMBASE, and Cochrane Controlled Trials Registry databases (from inception to February 2016). Human studies reporting Tb and mortality of patients with sepsis were included in the analyses. Average Tb with SEM and mortality rate of septic patient groups were extracted by two authors independently. Results Forty-two studies reported Tb and mortality ratios in septic patients (n = 10,834). Pearson correlation analysis revealed weak negative linear correlation (R2 = 0.2794) between Tb and mortality. With forest plot analysis, we found a 22.2% (CI, 19.2–25.5) mortality rate in septic patients with fever (Tb > 38.0°C), which was higher, 31.2% (CI, 25.7–37.3), in normothermic patients, and it was the highest, 47.3% (CI, 38.9–55.7), in hypothermic patients (Tb < 36.0°C). Meta-regression analysis showed strong negative linear correlation between Tb and mortality rate (regression coefficient: -0.4318; P < 0.001). Mean Tb of the patients was higher in the lowest mortality quartile than in the highest: 38.1°C (CI, 37.9–38.4) vs 37.1°C (CI, 36.7–37.4). Conclusions Deep Tb shows negative correlation with the clinical outcome in sepsis. Fever predicts lower, while hypothermia higher mortality rates compared with normal Tb. Septic patients with the lowest (< 25%) chance of mortality have higher Tb than those with the highest chance (> 75%).
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Affiliation(s)
- Zoltan Rumbus
- Institute for Translational Medicine, Medical School, University of Pecs, Pecs, Hungary
| | - Robert Matics
- Institute for Translational Medicine, Medical School, University of Pecs, Pecs, Hungary
| | - Peter Hegyi
- Institute for Translational Medicine, Medical School, University of Pecs, Pecs, Hungary
- Department of Translational Medicine, First Department of Medicine, University of Pecs, Pecs, Hungary
- Momentum Gastroenterology Multidisciplinary Research Group, Hungarian Academy of Sciences - University of Szeged, Szeged, Hungary
| | - Csaba Zsiboras
- Institute for Translational Medicine, Medical School, University of Pecs, Pecs, Hungary
| | - Imre Szabo
- Department of Gastroenterology, First Department of Medicine, University of Pecs, Pecs, Hungary
| | - Anita Illes
- Department of Gastroenterology, First Department of Medicine, University of Pecs, Pecs, Hungary
| | - Erika Petervari
- Institute for Translational Medicine, Medical School, University of Pecs, Pecs, Hungary
| | - Marta Balasko
- Institute for Translational Medicine, Medical School, University of Pecs, Pecs, Hungary
| | - Katalin Marta
- Institute for Translational Medicine, Medical School, University of Pecs, Pecs, Hungary
- Department of Translational Medicine, First Department of Medicine, University of Pecs, Pecs, Hungary
| | - Alexandra Miko
- Institute for Translational Medicine, Medical School, University of Pecs, Pecs, Hungary
| | - Andrea Parniczky
- Institute for Translational Medicine, Medical School, University of Pecs, Pecs, Hungary
- Department of Gastroenterology, First Department of Medicine, University of Pecs, Pecs, Hungary
| | - Judit Tenk
- Institute for Translational Medicine, Medical School, University of Pecs, Pecs, Hungary
| | - Ildiko Rostas
- Institute for Translational Medicine, Medical School, University of Pecs, Pecs, Hungary
| | - Margit Solymar
- Institute for Translational Medicine, Medical School, University of Pecs, Pecs, Hungary
| | - Andras Garami
- Institute for Translational Medicine, Medical School, University of Pecs, Pecs, Hungary
- * E-mail:
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29
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Steiner AA, Fonseca MT, Soriano FG. Should we assume that hypothermia is a dysfunction in sepsis? Crit Care 2017; 21:8. [PMID: 28073371 PMCID: PMC5225576 DOI: 10.1186/s13054-016-1584-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Affiliation(s)
- Alexandre A Steiner
- Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, Avenida Professor Lineu Prestes 1730, São Paulo, SP, 05508-000, Brazil.
| | - Monique T Fonseca
- Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, Avenida Professor Lineu Prestes 1730, São Paulo, SP, 05508-000, Brazil
| | - Francisco G Soriano
- Department of Emergency Medicine, Medical School, University of São Paulo, Avenida Doutor Arnaldo 455, São Paulo, SP, 01246-903, Brazil
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Dantonio V, Batalhão ME, Fernandes MHMR, Komegae EN, Buqui GA, Lopes NP, Gargaglioni LH, Carnio ÉC, Steiner AA, Bícego KC. Nitric oxide and fever: immune-to-brain signaling vs. thermogenesis in chicks. Am J Physiol Regul Integr Comp Physiol 2016; 310:R896-905. [DOI: 10.1152/ajpregu.00453.2015] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Accepted: 03/14/2016] [Indexed: 12/18/2022]
Abstract
Nitric oxide (NO) plays a role in thermogenesis but does not mediate immune-to-brain febrigenic signaling in rats. There are suggestions of a different situation in birds, but the underlying evidence is not compelling. The present study was designed to clarify this matter in 5-day-old chicks challenged with a low or high dose of bacterial LPS. The lower LPS dose (2 μg/kg im) induced fever at 3–5 h postinjection, whereas 100 μg/kg im decreased core body temperature (Tc) (at 1 h) followed by fever (at 4 or 5 h). Plasma nitrate levels increased 4 h after LPS injection, but they were not correlated with the magnitude of fever. The NO synthase inhibitor ( NG-nitro-l-arginine methyl ester, l-NAME; 50 mg/kg im) attenuated the fever induced by either dose of LPS and enhanced the magnitude of the Tc reduction induced by the high dose in chicks at 31–32°C. These effects were associated with suppression of metabolic rate, at least in the case of the high LPS dose. Conversely, the effects of l-NAME on Tc disappeared in chicks maintained at 35–36°C, suggesting that febrigenic signaling was essentially unaffected. Accordingly, the LPS-induced rise in the brain level of PGE2 was not affected by l-NAME. Moreover, l-NAME augmented LPS-induced huddling, which is indicative of compensatory mechanisms to run fever in the face of attenuated thermogenesis. Therefore, as in rats, systemic inhibition of NO synthesis attenuates LPS-induced fever in chicks by affecting thermoeffector activity and not by interfering with immune-to-brain signaling. This may constitute a conserved effect of NO in endotherms.
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Affiliation(s)
- Valter Dantonio
- Department of Animal Morphology and Physiology, College of Agricultural and Veterinarian Sciences, São Paulo State University, Jaboticabal, São Paulo, Brazil
- National Institute of Science and Technology-Comparative Physiology (INCT-Fisiologia Comparada), Rio Claro, São Paulo, Brazil
| | - Marcelo E. Batalhão
- Nursing School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Marcia H. M. R. Fernandes
- Department of Animal Science, College of Agricultural and Veterinarian Sciences, São Paulo State University, Jaboticabal, São Paulo, Brazil
| | - Evilin N. Komegae
- Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, São Paulo, Brazil; and
| | - Gabriela A. Buqui
- Department of Physics and Chemistry, Núcleo de Pesquisa em Produtos Naturais e Sintéticos, Faculty of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Norberto P. Lopes
- Department of Physics and Chemistry, Núcleo de Pesquisa em Produtos Naturais e Sintéticos, Faculty of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Luciane H. Gargaglioni
- Department of Animal Morphology and Physiology, College of Agricultural and Veterinarian Sciences, São Paulo State University, Jaboticabal, São Paulo, Brazil
- National Institute of Science and Technology-Comparative Physiology (INCT-Fisiologia Comparada), Rio Claro, São Paulo, Brazil
| | - Évelin C. Carnio
- Nursing School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Alexandre A. Steiner
- Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, São Paulo, Brazil; and
| | - Kênia C. Bícego
- Department of Animal Morphology and Physiology, College of Agricultural and Veterinarian Sciences, São Paulo State University, Jaboticabal, São Paulo, Brazil
- National Institute of Science and Technology-Comparative Physiology (INCT-Fisiologia Comparada), Rio Claro, São Paulo, Brazil
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Fonseca MT, Rodrigues AC, Cezar LC, Fujita A, Soriano FG, Steiner AA. Spontaneous hypothermia in human sepsis is a transient, self-limiting, and nonterminal response. J Appl Physiol (1985) 2016; 120:1394-401. [PMID: 26989218 DOI: 10.1152/japplphysiol.00004.2016] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2016] [Accepted: 03/15/2016] [Indexed: 11/22/2022] Open
Abstract
Hypothermia in sepsis is generally perceived as something dysregulated and progressive although there has been no assessment on the natural course of this phenomenon in humans. This was the first study on the dynamics of hypothermia in septic patients not subjected to active rewarming, and the results were surprising. A sample of 50 subjects presenting with spontaneous hypothermia during sepsis was drawn from the 2005-2012 database of an academic hospital. Hypothermia was defined as body temperature below 36.0°C for longer than 2 h, with at least one reading of 35.5°C or less. The patients presented with 138 episodes of hypothermia, 21 at the time of the sepsis diagnosis and 117 with a later onset. However, hypothermia was uncommon in the final 12 h of life of the patients that succumbed. The majority (97.1%) of the hypothermic episodes were transient and self-limited; the median recovery time was 6 h; body temperature rarely fell below 34.0°C. Bidirectional oscillations in body temperature were evident in the course of hypothermia. Nearly half of the hypothermic episodes had onset in the absence of shock or respiratory distress, and the incidence of hypothermia was not increased during either of these conditions. Usage of antipyretic drugs, sedatives, neuroleptics, or other medications did not predict the onset of hypothermia. In conclusion, hypothermia appears to be a predominantly transient, self-limiting, and nonterminal phenomenon that is inherent to human sepsis. These characteristics resemble those of the regulated hypothermia shown to replace fever in animal models of severe systemic inflammation.
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Affiliation(s)
- Monique T Fonseca
- Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Abner C Rodrigues
- Institute of Mathematics and Statistics, University of São Paulo, São Paulo, Brazil
| | - Luana C Cezar
- Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Andre Fujita
- Institute of Mathematics and Statistics, University of São Paulo, São Paulo, Brazil
| | | | - Alexandre A Steiner
- Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil;
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Abstract
This report aims to facilitate the implementation of the Three Rs (replacement, reduction, and refinement) in the use of animal models or procedures involving sepsis and septic shock, an area where there is the potential of high levels of suffering for animals. The emphasis is on refinement because this has the greatest potential for immediate implementation. Specific welfare issues are identified and discussed, and practical measures are proposed to reduce animal use and suffering as well as reducing experimental variability and increasing translatability. The report is based on discussions and submissions from a nonregulatory expert working group consisting of veterinarians, animal technologists, and scientists with expert knowledge relevant to the field.
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Accompanying mild hypothermia significantly improved the prognosis of septic mice than artificial mild hypothermia. Am J Emerg Med 2015; 33:1651-8. [DOI: 10.1016/j.ajem.2015.08.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Revised: 07/29/2015] [Accepted: 08/02/2015] [Indexed: 02/05/2023] Open
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34
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Steiner AA. Reduced oxygen utilization in septic shock: disorder or adaptation? Temperature (Austin) 2015; 2:447-8. [PMID: 27227060 PMCID: PMC4843942 DOI: 10.1080/23328940.2014.996484] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Revised: 12/05/2014] [Accepted: 12/05/2014] [Indexed: 10/25/2022] Open
Abstract
A fall in oxygen utilization during septic or endotoxic shock is thought to reflect circulatory hypoxia or mitochondrial dysfunction, but these pathology-oriented hypotheses do not explain all clinical observations. Here we discuss an alternative hypothesis of how oxygen utilization could fall as the result of a physiological thermometabolic adaptation.
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Affiliation(s)
- Alexandre A Steiner
- Department of Immunology; Institute of Biomedical Sciences; University of São Paulo ; São Paulo, SP Brazil
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