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Pruett S, Tan W, Howell GE, Nanduri B. Dosage scaling of alcohol in binge exposure models in mice: An empirical assessment of the relationship between dose, alcohol exposure, and peak blood concentrations in humans and mice. Alcohol 2020; 89:9-17. [PMID: 32259574 DOI: 10.1016/j.alcohol.2020.03.011] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 03/18/2020] [Accepted: 03/23/2020] [Indexed: 02/08/2023]
Abstract
Binge drinking is a remarkably prevalent behavior. In 2015, 27% of U.S. residents 18 years old or older reported at least one episode of binge drinking in the previous month. Rodent models for binge drinking are widely used to study the mechanisms by which alcohol causes a variety of adverse health effects in humans. Concerns have been raised that many binge-drinking studies in rodents involve alcohol doses that would be unrealistically high in humans. Allometric dosage scaling can be used to estimate the dose of a drug or chemical in mice that would be necessary to achieve similar biological effects at a realistic dose in humans. However, it has become apparent that no single allometric conversion factor is applicable for all drugs and chemicals, so it is necessary to evaluate each compound empirically. In the present study, we compared the area under the blood alcohol concentration vs. time curve (AUC) and the peak blood alcohol concentration following oral alcohol administration at various doses in mice and humans, using data from previously published studies. The results demonstrated that the oral dose of alcohol must be larger in mice (on a g of alcohol to kg of body weight basis) than in humans to achieve similar alcohol AUC values or to achieve similar peak concentrations in the blood. The dose required in mice was about 2-fold greater than the dose required in humans to achieve similar alcohol AUC and peak concentrations. The results shown here were substantially different from the average 5-12-fold difference between mice and humans calculated in previous studies using agents other than alcohol. Results shown here demonstrate that an empirical approach using data from several independent experiments provides information needed to determine the alcohol dose in mice that produces a similar level of exposure (AUC and peak concentration) as in humans. The results indicate that a single alcohol dose in the range of 5-6 g/kg, a range often used in mouse models for binge drinking, is not excessive when modeling human binge drinking. Results presented here illustrate that in mice both alcohol AUC and peak alcohol concentration correlate well with an important biological effect - activation of the hypothalamic-pituitary-adrenal axis - as indicated by increased corticosterone AUC values.
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Bhatty M, Tan W, Basco M, Pruett S, Nanduri B. Binge alcohol consumption 18 h after induction of sepsis in a mouse model causes rapid overgrowth of bacteria, a cytokine storm, and decreased survival. Alcohol 2017; 63:9-17. [PMID: 28847384 DOI: 10.1016/j.alcohol.2016.11.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Revised: 11/14/2016] [Accepted: 11/17/2016] [Indexed: 11/30/2022]
Abstract
Alcohol abuse increases vulnerability to infections and infection-related mortality. In previous studies, we found that acute alcohol abuse in a binge-drinking model in mice decreased resistance to bacterial sepsis when alcohol was administered near the time of bacterial challenge. In the present study, we investigated the effects of alcohol administered later in the course of sepsis (18 h after injection of Escherichia coli). Our working hypothesis was that decreased production of cytokines caused by alcohol at this time would actually improve survival, because overproduction of pro-inflammatory mediators is thought to be the proximate cause of mortality in sepsis. Unexpectedly, administration of alcohol late in the course of sepsis led to a rapid increase in the number of viable bacteria in the peritoneal cavity. Significant increases in the concentrations of several cytokines and chemokines coincided with the increased number of bacteria in alcohol-treated mice and decreased survival time. These results demonstrated our working hypothesis to be incorrect, and reiterated the complexity of sepsis. Hypothermia is a consistent feature in this model of sepsis. In control mice (E. coli only), body temperature was near normal by 18 h or 21 h after administration of E. coli, but in mice treated with alcohol 18 h after E. coli, hypothermia was significant 3 h later and ultimately mortality was significantly increased. However, counteracting the hypothermic effect of alcohol by external warming of mice led to earlier mortality, demonstrating that hypothermia was not the major cause of mortality. These results, along with previous results from studies in which alcohol was given before initiation of sepsis, suggest that decreased cytokine and chemokine production may not be the key effect of alcohol that decreases resistance to sepsis. It seems more likely that suppression of mechanisms by which macrophages and neutrophils kill bacteria is critical, and this can occur even in the presence of high levels of cytokines and chemokines.
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Affiliation(s)
- Minny Bhatty
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, MS, USA
| | - Wei Tan
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, MS, USA
| | - Maria Basco
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, MS, USA
| | - Stephen Pruett
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, MS, USA.
| | - Bindu Nanduri
- Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, MS, USA
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Pavón FJ, Marco EM, Vázquez M, Sánchez L, Rivera P, Gavito A, Mela V, Alén F, Decara J, Suárez J, Giné E, López-Moreno JA, Chowen J, Rodríguez-de-Fonseca F, Serrano A, Viveros MP. Effects of Adolescent Intermittent Alcohol Exposure on the Expression of Endocannabinoid Signaling-Related Proteins in the Spleen of Young Adult Rats. PLoS One 2016; 11:e0163752. [PMID: 27662369 PMCID: PMC5035052 DOI: 10.1371/journal.pone.0163752] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Accepted: 09/13/2016] [Indexed: 12/15/2022] Open
Abstract
Intermittent alcohol exposure is a common pattern of alcohol consumption among adolescents and alcohol is known to modulate the expression of the endocannabinoid system (ECS), which is involved in metabolism and inflammation. However, it is unknown whether this pattern may have short-term consequences on the ECS in the spleen. To address this question, we examined the plasma concentrations of metabolic and inflammatory signals and the splenic ECS in early adult rats exposed to alcohol during adolescence. A 4-day drinking in the dark (DID) procedure for 4 weeks was used as a model of intermittent forced-alcohol administration (20%, v/v) in female and male Wistar rats, which were sacrificed 2 weeks after the last DID session. First, there was no liver damage or alterations in plasma metabolic parameters. However, certain plasma inflammatory signals were altered according to sex and alcohol exposition. Whereas fractalkine [chemokine (C-X3-C motif) ligand 1] was only affected by sex with lower concentration in male rats, there was an interaction between sex and alcohol exposure in the TNF-α and interleukin-6 concentrations and only female rats displayed changes. Regarding the mRNA and protein expression of the ECS, the receptors and endocannabinoid-synthesizing enzymes were found to be altered with area-specific expression patterns in the spleen. Overall, whereas the expression of the cannabinoid receptor CB1 and the nuclear peroxisome proliferator-activated receptor PPARα were lower in alcohol-exposed rats compared to control rats, the CB2 expression was higher. Additionally, the N-acyl-phosphatidylethanolamine-specific phospholipase D expression was high in female alcohol-exposed rats and low in male alcohol-exposed rats. In conclusion, intermittent alcohol consumption during adolescence may be sufficient to induce short-term changes in the expression of splenic endocannabinoid signaling-related proteins and plasma pro-inflammatory cytokines in young adult rats with a strong sexual dimorphism. The potential impact of these alterations in early adulthood remains to be elucidated.
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Affiliation(s)
- Francisco Javier Pavón
- Unidad Gestión Clínica de Salud Mental, Instituto de Investigación Biomédica de Málaga (IBIMA), Hospital Regional Universitario de Málaga-Universidad de Málaga, Málaga, Spain
| | - Eva María Marco
- Departamento de Fisiología (Fisiología Animal II), Facultad de Biología, Universidad Complutense, Madrid, Spain
| | - Mariam Vázquez
- Unidad Gestión Clínica de Salud Mental, Instituto de Investigación Biomédica de Málaga (IBIMA), Hospital Regional Universitario de Málaga-Universidad de Málaga, Málaga, Spain
| | - Laura Sánchez
- Unidad Gestión Clínica de Salud Mental, Instituto de Investigación Biomédica de Málaga (IBIMA), Hospital Regional Universitario de Málaga-Universidad de Málaga, Málaga, Spain
| | - Patricia Rivera
- Unidad Gestión Clínica de Salud Mental, Instituto de Investigación Biomédica de Málaga (IBIMA), Hospital Regional Universitario de Málaga-Universidad de Málaga, Málaga, Spain
| | - Ana Gavito
- Unidad Gestión Clínica de Salud Mental, Instituto de Investigación Biomédica de Málaga (IBIMA), Hospital Regional Universitario de Málaga-Universidad de Málaga, Málaga, Spain
| | - Virginia Mela
- Departamento de Fisiología (Fisiología Animal II), Facultad de Biología, Universidad Complutense, Madrid, Spain
| | - Francisco Alén
- Unidad Gestión Clínica de Salud Mental, Instituto de Investigación Biomédica de Málaga (IBIMA), Hospital Regional Universitario de Málaga-Universidad de Málaga, Málaga, Spain
| | - Juan Decara
- Unidad Gestión Clínica de Salud Mental, Instituto de Investigación Biomédica de Málaga (IBIMA), Hospital Regional Universitario de Málaga-Universidad de Málaga, Málaga, Spain
| | - Juan Suárez
- Unidad Gestión Clínica de Salud Mental, Instituto de Investigación Biomédica de Málaga (IBIMA), Hospital Regional Universitario de Málaga-Universidad de Málaga, Málaga, Spain
| | - Elena Giné
- Departamento de Biología Celular, Facultad de Psicología, Universidad Complutense, Madrid, Spain
| | | | - Julie Chowen
- Servicio de Pediatría y Endocrinología Pediátrica, Hospital Infantil Universitario Niño Jesús, Instituto de Investigación Sanitaria del Hospital Universitario de La Princesa (IP), Madrid, Spain
- Centro de Investigación Biomédica en Red de la Fisiopatología de la Obesidad y Nutrición (CIBERobn) Instituto de Salud Carlos III, Madrid, Spain
| | - Fernando Rodríguez-de-Fonseca
- Unidad Gestión Clínica de Salud Mental, Instituto de Investigación Biomédica de Málaga (IBIMA), Hospital Regional Universitario de Málaga-Universidad de Málaga, Málaga, Spain
| | - Antonia Serrano
- Unidad Gestión Clínica de Salud Mental, Instituto de Investigación Biomédica de Málaga (IBIMA), Hospital Regional Universitario de Málaga-Universidad de Málaga, Málaga, Spain
- * E-mail: (ASC); (MPV)
| | - María Paz Viveros
- Departamento de Fisiología (Fisiología Animal II), Facultad de Biología, Universidad Complutense, Madrid, Spain
- * E-mail: (ASC); (MPV)
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The In Vivo Granulopoietic Response to Dexamethasone Injection Is Abolished in Perforin-Deficient Mutant Mice and Corrected by Lymphocyte Transfer from Nonsensitized Wild-Type Donors. Mediators Inflamm 2015; 2015:495430. [PMID: 26063973 PMCID: PMC4434200 DOI: 10.1155/2015/495430] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Revised: 03/27/2015] [Accepted: 04/01/2015] [Indexed: 12/21/2022] Open
Abstract
Exogenously administered glucocorticoids enhance eosinophil and neutrophil granulocyte production from murine bone-marrow. A hematological response dependent on endogenous glucocorticoids underlies bone-marrow eosinophilia induced by trauma or allergic sensitization/challenge. We detected a defect in granulopoiesis in nonsensitized, perforin-deficient mice. In steady-state conditions, perforin- (Pfp-) deficient mice showed significantly decreased bone-marrow and blood eosinophil and neutrophil counts, and colony formation in response to GM-CSF, relative to wild-type controls of comparable age and/or weight. By contrast, peripheral blood or spleen total cell and lymphocyte numbers were not affected by perforin deficiency. Dexamethasone enhanced colony formation by GM-CSF-stimulated progenitors from wild-type controls, but not Pfp mice. Dexamethasone injection increased bone-marrow eosinophil and neutrophil counts in wild-type controls, but not Pfp mice. Because perforin is expressed in effector lymphocytes, we examined whether this defect would be corrected by transferring wild-type lymphocytes into perforin-deficient recipients. Short-term reconstitution of the response to dexamethasone was separately achieved for eosinophils and neutrophils by transfer of distinct populations of splenic lymphocytes from nonsensitized wild-type donors. Transfer of the same amount of splenic lymphocytes from perforin-deficient donors was ineffective. This demonstrates that the perforin-dependent, granulopoietic response to dexamethasone can be restored by transfer of innate lymphocyte subpopulations.
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Liu Z, Yuan C, Pruett SB. Machine learning analysis of the relationship between changes in immunological parameters and changes in resistance to Listeria monocytogenes: a new approach for risk assessment and systems immunology. Toxicol Sci 2012; 129:57-73. [PMID: 22696237 DOI: 10.1093/toxsci/kfs201] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
No method has been reported to predict, even approximately, the impact of mild-to-moderate changes in several immunological parameters on resistance to infection. The ability to make such predictions would be useful in risk assessment. In addition, equations that predict host resistance on the basis of changes in components of a complex biological system (the immune system) would fulfill one of the major goals of systems biology. In this study, multiple machine learning classification methods were used to predict the effects of a series of drugs and chemicals on host resistance to Listeria monocytogenes in mice on the basis of changes in several holistic immunological parameters. A data set produced under the sponsorship of the National Toxicology Program (NTP) was used in this study. The NTP data set was found to have a high percentage of missing data and to be noisy (probably due to the intrinsically stochastic nature of immune responses). Data preprocessing steps were used to mitigate these problems. In evaluating the machine learning classifiers, we first randomly partitioned the NTP data set into 10 subsets. Each time, we used nine subsets of the data to train the machine learning classifiers, and the remaining single subset to predict outcomes with regard to host resistance. This process was repeated until all 10 combinations of the 9-1 split of the subsets have been tested. The best of the classifiers predicted host resistance outcome correctly for 94.7% of cases, a result which indicates it is possible to identify mathematical expressions that will be useful for risk assessment and to establish a basis for systems immunology.
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Affiliation(s)
- Zhifa Liu
- Department of Computer Science and Engineering, Bagley College of Engineering, Mississippi State University, Mississippi 39762, USA
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Mitra S, Keswani T, Dey M, Bhattacharya S, Sarkar S, Goswami S, Ghosh N, Dutta A, Bhattacharyya A. Copper-induced immunotoxicity involves cell cycle arrest and cell death in the spleen and thymus. Toxicology 2012; 293:78-88. [DOI: 10.1016/j.tox.2011.12.013] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2011] [Revised: 12/23/2011] [Accepted: 12/29/2011] [Indexed: 02/03/2023]
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The role of glucocorticoids in the immediate vs. delayed effects of acute ethanol exposure on cytokine production in a binge drinking model. Int Immunopharmacol 2011; 11:755-61. [PMID: 21315785 DOI: 10.1016/j.intimp.2011.01.029] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2010] [Revised: 01/26/2011] [Accepted: 01/27/2011] [Indexed: 01/12/2023]
Abstract
BACKGROUND Acute ethanol administration just prior to a stimulus, such as the viral mimic poly I:C, results in decreased proinflammatory cytokine production. Studies have indicated that this suppression is not primarily mediated by glucocorticoids (corticosterone in mice) released in the ethanol-induced stress response. Fewer studies have been done on the effects of acute ethanol administration 12 or more hours prior to a stimulus. The purpose of this study was to determine the role of corticosterone on these effects. Also, since gender differences occur in immune responses, separate experiments were performed using male and female mice. METHODS Mice were treated with ethanol 15 min or 12h before stimulation by poly I:C to demonstrate immunosuppressive effects of ethanol on cytokine production. A glucocorticoid synthesis inhibitor was used to manipulate corticosterone levels. RESULTS Short-term and persistent effects of acute ethanol exposure on corticosterone and cytokine levels were nearly identical in males and females. Blocking glucocorticoid synthesis altered the inhibition of some cytokines, particularly IL-6, in females, but not in males. CONCLUSION These results indicate that the short-term effects of acute ethanol on poly I:C-induced cytokine production are not primarily mediated by corticosterone in male or female mice. In female mice, however, corticosterone does appear to mediate the persistent effects of acute ethanol administration on poly I:C- induced IL-6 levels. Since many IL-6 related disorders are gender associated, further research into the bidirectional effects of the HPG and HPA axes on alterations in cytokine production mediated by ethanol is warranted.
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The role of stress mediators in modulation of cytokine production by ethanol. Toxicol Appl Pharmacol 2009; 239:98-105. [PMID: 19500611 DOI: 10.1016/j.taap.2009.05.023] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2009] [Revised: 05/21/2009] [Accepted: 05/28/2009] [Indexed: 11/22/2022]
Abstract
Acute ethanol exposure in humans and in animal models activates the hypothalamic-pituitary-adrenal (HPA) axis and the sympathetic nervous system (SNS); the resultant increases in concentration of neuroendocrine mediators contribute to some of the immunosuppressive effects of ethanol. However, the role of these mediators in the ethanol-induced inhibition of inflammatory responses is not clear. This is complicated by the fact that most inflammatory stimuli also activate the HPA axis and SNS, and it has not been determined if ethanol plus an inflammatory stimulus increases these stress responses. Addressing this issue is the major focus of the study described herein. Complementary approaches were used, including quantitative assessment of the stress response in mice treated with polyinosinic-polycytidylic acid (poly I:C, as an inflammatory stimulus) and inhibition of the production or action of key HPA axis and SNS mediators. Treatment of mice with ethanol shortly before treatment with poly I:C yielded a significant increase in the corticosterone response as compared to the response to poly I:C alone, but the increase was small and not likely sufficient to account for the anti-inflammatory effects of ethanol. Inhibition of catecholamine and glucocorticoid production by adrenalectomy, and inhibition of catecholamine action with a sustained release antagonist (nadalol) supported this conclusion and revealed that "excess" stress responses associated with ethanol treatment is not the mechanism of suppression of pro-inflammatory cytokine production, but stress-induced corticosterone does regulate production of several of these cytokines, which has not previously been reported.
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Pruett S, Hébert P, Lapointe JM, Reagan W, Lawton M, Kawabata TT. Characterization of the Action of Drug-Induced Stress Responses on the Immune System: Evaluation of Biomarkers for Drug-Induced Stress in Rats. J Immunotoxicol 2008; 4:25-38. [DOI: 10.1080/15476910601115150] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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10
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Myers LP, Fan R, Zheng Q, Pruett SB. Sodium Methyldithiocarbamate Causes Thymic Atrophy by an Indirect Mechanism of Corticosterone Up-Regulation. J Immunotoxicol 2008; 2:97-106. [PMID: 18958663 DOI: 10.1080/15476910591006673] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
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11
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Gao S, Wang Y, Zhang P, Dong Y, Li B. Subacute Oral Exposure to Dibromoacetic Acid Induced Immunotoxicity and Apoptosis in the Spleen and Thymus of the mice. Toxicol Sci 2008; 105:331-41. [DOI: 10.1093/toxsci/kfn139] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
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12
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Glover M, Pruett SB. Role of corticosterone in immunosuppressive effects of acute ethanol exposure on Toll-like receptor mediated cytokine production. J Neuroimmune Pharmacol 2006; 1:435-42. [PMID: 18040816 DOI: 10.1007/s11481-006-9037-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2006] [Accepted: 07/13/2006] [Indexed: 01/12/2023]
Abstract
Acute ethanol (EtOH) exposure causes a stress response in humans, nonhuman primates, and rodents. Previous study results indicate that the suppression of some immunological parameters by EtOH is mediated in part or completely by elevated corticosterone concentrations induced by EtOH. However, initial results suggested that corticosterone is not involved in the modulation of cytokine production by macrophages in response to polyinosinic polycytidylic acid (poly I:C). New studies were conducted to further evaluate the role of corticosterone in EtOH-mediated changes in production of interleukin-6 (IL-6), IL-10, and IL-12 in serum and peritoneal fluid in mice treated with poly I:C or lipopolysaccharide (LPS). Suppression of IL-6, but not IL-12, production by EtOH was found to be mediated by corticosterone. However, poly I:C, LPS, and EtOH all caused similar elevations of corticosterone concentrations; thus, it is not clear if EtOH is required to induce levels or durations of corticosterone needed to mediate the observed effects. The situation with IL-10 was more complicated. Inhibition of corticosterone synthesis with aminoglutethimide prevented the increase in IL-10 production caused by EtOH plus poly I:C as compared to poly I:C only. This indicates that this increase is dependent on corticosterone, but exogenous corticosterone plus poly I:C did not increase IL-10 production. Thus, EtOH and corticosterone are required. However, with LPS inhibition of corticosterone synthesis (using aminoglutethimide) or inhibition of its action (using mifepristone) further increased, or did not affect IL-10 concentrations, suggesting fundamental differences in the signaling pathways leading from poly I:C and LPS to IL-10 production.
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Affiliation(s)
- Mitzi Glover
- Department of Cellular Biology and Anatomy, Louisiana State University Health Sciences Center, LSUHSC-S, 1501 Kings Highway, Shreveport, LA 71130, USA
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Pruett SB, Fan R, Zheng Q. Involvement of three mechanisms in the alteration of cytokine responses by sodium methyldithiocarbamate. Toxicol Appl Pharmacol 2006; 213:172-8. [PMID: 16321413 DOI: 10.1016/j.taap.2005.10.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2005] [Revised: 10/06/2005] [Accepted: 10/16/2005] [Indexed: 01/20/2023]
Abstract
Sodium methyldithiocarbamate (SMD) is the third most abundantly used conventional pesticide in the U.S. We recently reported that it alters the induction of cytokine production mediated though Toll-like receptor (TLR) 4 at relevant dosages in mice. Its chemical properties and evidence from the literature suggest the potential mechanisms of action for this compound. It could either act as a free radical scavenger (by means of its free S(-)group) or promote oxidation by breaking down to form methylisothiocyanate, which can deplete glutathione. It is a potent copper chelator and may affect the availability of copper to a number of copper-dependent enzymes (including some signaling molecules). SMD induces a classical neuroendocrine stress response characterized by elevated serum corticosterone concentrations, which could affect cytokine production. Although each of these mechanisms could potentially contribute to altered cytokine responses, direct evidence is lacking. The present study was conducted to obtain such evidence. The role of redox balance was investigated by pretreating mice with N-acetyl cysteine (NAC), which increases cellular glutathione concentrations, before administration of SMD. NAC exacerbated the SMD-induced suppression of IL-12 and the SMD-induced enhancement of IL-10 in the serum. The role of copper chelation was investigated by comparing the effects of SMD with an equimolar dose to SMD that was administered in the form of a copper chelation complex. Addition of copper significantly decreased the action of SMD on IL-12 production but not on IL-10 production. The role of the stress response was investigated by pretreating mice with antagonists of corticosterone and catecholamines. This treatment partially prevented the action of SMD on IL-10 and IL-12 in the peritoneal fluid. The results suggest that all of the proposed mechanisms have some role in the alteration of cytokine production by SMD.
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Affiliation(s)
- Stephen B Pruett
- Department of Cellular Biology and Anatomy, Louisiana State University Health Sciences Center, 1501 Kings Highway, Shreveport, 71130, USA.
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Pruett BS, Pruett SB. An explanation for the paradoxical induction and suppression of an acute phase response by ethanol. Alcohol 2006; 39:105-10. [PMID: 17134663 PMCID: PMC1764540 DOI: 10.1016/j.alcohol.2006.08.003] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2006] [Revised: 08/12/2006] [Accepted: 08/14/2006] [Indexed: 11/25/2022]
Abstract
Binge ethanol (EtOH) consumption suppresses inflammatory responses and resistance to infection, but paradoxically it is associated with increased levels of acute phase proteins (which are indicators of inflammation) and an increased risk of inflammation-mediated pathologies such as cardiovascular disease and cirrhosis of the liver. The latter effect may be mediated by increased translocation of bacteria leading to activation of toll-like receptor 4 (TLR4). In this study, the dose-response and time course of the effects of EtOH alone or EtOH in conjunction with a TLR4 agonist (lipopolysaccharide [LPS]) were evaluated in mice. EtOH alone at a dosage of 6 g/kg induced an acute phase response (as indicated by enzyme-linked immunosorbent assay for serum amyloid A and serum amyloid P) that was maximal 24 h after dosing. Lower dosages of EtOH did not have this effect but did suppress the acute phase response to LPS and the production of interleukin-6 up to 3 h after dosing. EtOH at 6 g/kg did not induce an acute phase response in C3H/HeJ (TLR4 mutant) mice, indicating that this response is mediated through TLR4. These results provide a resolution for the apparently paradoxical pro- and anti-inflammatory actions of EtOH with regard to acute phase responses.
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Affiliation(s)
- Brandon S Pruett
- Department of Cellular Biology & Anatomy, Louisiana State University Health Sciences Center, 1501 Kings Highway, Shreveport, LA 71130, USA
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Yang Q, Gonzalez FJ. Peroxisome proliferator-activated receptor alpha regulates B lymphocyte development via an indirect pathway in mice. Biochem Pharmacol 2005; 68:2143-50. [PMID: 15498504 DOI: 10.1016/j.bcp.2004.08.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2004] [Accepted: 08/06/2004] [Indexed: 11/16/2022]
Abstract
Peroxisome proliferator-activator receptor alpha (PPARalpha), a member of the nuclear receptor superfamily, has been implicated in the regulation of inflammation and immune response. Adaptive immune responses are suppressed by exposure to PPARalpha agonists, resulting in severe thymus and spleen atrophy. In addition, the decline in both T and B cells is due in part to the loss of splenocytes upon exposure to PPARalpha agonists. Thus, the current study was designed to examine the effect of Wy-14,643, a potent PPARalpha agonist, on B cell development in bone marrow from wild-type and PPARalpha-null mice. Significantly decrease in pro/pre-B cell and total B220(+) cell was observed in wild-type mice in bone marrow upon Wy-14,643 treatment, but not in PPARalpha-null mice. Immature and mature B cell populations are not affected. This suggests that PPARalpha is involved in the development of B cell during lymphoid lineage. However, surprisingly, PPARalpha mRNA was absent in bone marrow as revealed by RT-PCR. Therefore, the effect of PPARalpha on B cell development is by an indirect mechanism.
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Affiliation(s)
- Qian Yang
- Laboratory of Metabolism, National Cancer Institute, National Institutes of Health, Building 37, Room 3106B, Bethesda, MD 20892, USA
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16
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de la Rosa P, Barnett JB, Schafer R. Characterization of thymic atrophy and the mechanism of thymocyte depletion after in vivo exposure to a mixture of herbicides. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2005; 68:81-98. [PMID: 15762548 DOI: 10.1080/15287390590886072] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
3,4-Dichloropropionanilide (propanil) and 2,4-dichlorophenoxyacetic acid (2,4-D) are two commonly used herbicides that are marketed as a chemical mixture. It was hypothesized that the interaction between these two herbicides, when administered as a mixture, would result in a greater effect on the immune system than the individual components of the mixture. The present study demonstrates in a murine model that a mixture of propanil and 2,4-D, when compared to single herbicide exposures, exacerbates decreases in thymocyte populations 2 d postexposure and inhibits the repopulation of T-cells in the thymus 7 d postexposure. Exposure to 150 mg herbicide/kg body weight of propanil or 2,4-D alone had no effect on thymus weight. In contrast, decreases in the ratio of thymus weight to body weight (TW:BW) occurred 2 d after treatment with the mixture of 150 mg propanil/kg body weight + 150 mg 2,4-D/kg body weight (150/150). Thymic atrophy was associated with a decrease in the double-positive thymocyte population (CD4+CD8+) and correlated with sera corticosterone levels from 600 to 1000 pg/ml. Therefore, the hypothesis was tested that glucocorticoids, induced after exposure to herbicides, were responsible for the thymic atrophy and depletion of thymocytes. However, similar levels of corticosterone were induced after exposure to 50, 100, or 150 mg propanil/kg body weight, and 50/50 or 100/100 mixture treatments, doses that did not produce thymic atrophy or cell loss. In addition, RU 486, a glucocorticoid receptor blocker, only partially abrogated the thymic atrophy in mice exposed to the 150/150 mixture of herbicides. These results suggest that glucocorticoids are only partially responsible for herbicide-induced thymic atrophy. This study demonstrates that the effects of exposure to a mixture of chemicals cannot always be predicted based on single exposure data and emphasizes the importance of mixture-based studies.
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Pruett SB, Padgett EL. Thymus-derived glucocorticoids are insufficient for normal thymus homeostasis in the adult mouse. BMC Immunol 2004; 5:24. [PMID: 15522118 PMCID: PMC534100 DOI: 10.1186/1471-2172-5-24] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2004] [Accepted: 11/02/2004] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND It is unclear if thymus-derived glucocorticoids reach sufficient local concentrations to support normal thymus homeostasis, or if adrenal-derived glucocorticoids from the circulation are required. Modern approaches to this issue (transgenic mice that under or over express glucocorticoid receptor in the thymus) have yielded irreconcilably contradictory results, suggesting fundamental problems with one or more the transgenic mouse strains used. In the present study, a more direct approach was used, in which mice were adrenalectomized with or without restoration of circulating corticosterone using timed release pellets. Reversal of the increased number of thymocytes caused by adrenalectomy following restoration of physiological corticosterone concentrations would indicate that corticosterone is the major adrenal product involved in thymic homeostasis. RESULTS A clear relationship was observed between systemic corticosterone concentration, thymus cell number, and percentage of apoptotic thymocytes. Physiological concentrations of corticosterone in adrenalectomized mice restored thymus cell number to normal values and revealed differential sensitivity of thymocyte subpopulations to physiological and stress-inducible corticosterone concentrations. CONCLUSION This indicates that thymus-derived glucocorticoids are not sufficient to maintain normal levels of death by neglect in the thymus, but that apoptosis and possibly other mechanisms induced by physiological, non stress-induced levels of adrenal-derived corticosterone are responsible for keeping the total number of thymocytes within the normal range.
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Affiliation(s)
- Stephen B Pruett
- Department of Cellular Biology and Anatomy, Louisiana State University Health Sciences Center, 1501 Kings Highway, Shreveport, LA, USA
| | - Eric L Padgett
- Department of Cellular Biology and Anatomy, Louisiana State University Health Sciences Center, 1501 Kings Highway, Shreveport, LA, USA
- Wil Research Labs, 1407 George Road, Ashland, OH, USA
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Pruett SB, Fan R, Zheng Q. Acute ethanol administration profoundly alters poly I:C-induced cytokine expression in mice by a mechanism that is not dependent on corticosterone. Life Sci 2003; 72:1825-39. [PMID: 12586220 DOI: 10.1016/s0024-3205(02)02507-9] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Polyinosinic polycytidylic acid (poly I:C) is an analog of double stranded RNA, which is a common replication intermediate for many viruses. It acts through a toll-like receptor (TLR3) to induce a group of cytokines that can mediate host resistance to viruses and some cancers. The effect of ethanol (EtOH) on induction of this set of cytokines has not been determined. Mice were treated with a single dose of EtOH (by gavage) at the same time as poly I:C was administered (intraperitoneally), and cytokine mRNA expression was measured by RNAse protection assay. Concentrations of IFN-alpha, IL-10, and IL-12 in the serum were measured by ELISA. A single dose of EtOH suppressed induction of mRNA for IFN-alpha, IFN-beta, IFN-gamma, IL-6, IL-9, IL-12, and IL-15. The concentrations of IFN-alpha and IL-12 in the serum were also decreased. In contrast, IL-10 was minimally induced by poly I:C alone, but it was substantially induced by poly I:C plus EtOH. Dose response and time course studies demonstrated that significant alterations of IFN-alpha, IL-10, and IL-12 expression occurred at dosages as low as 4 g/kg (a dosage previously shown to produce blood EtOH concentrations of approximately 0.2%) and that alterations persisted at least 4-6 hr after administration of EtOH. The glucocorticoid synthesis inhibitor, aminoglutethimide, diminished corticosterone levels to normal, but did not block the effects of EtOH on cytokine expression. These results demonstrate that EtOH affects the expression of poly I:C-induced cytokines and that this action is not mediated by corticosterone. These results plus previously published findings are consistent with the idea that EtOH may be a generalized suppressor of toll-like receptor signaling.
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Affiliation(s)
- Stephen B Pruett
- Department of Cellular Biology and Anatomy, Louisiana State University Health Sciences Center, 1501 Kings Hwy., Shreveport, LA 71130, USA.
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19
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Yang Q, Xie Y, Eriksson AM, Nelson BD, DePierre JW. Further evidence for the involvement of inhibition of cell proliferation and development in thymic and splenic atrophy induced by the peroxisome proliferator perfluoroctanoic acid in mice. Biochem Pharmacol 2001; 62:1133-40. [PMID: 11597582 DOI: 10.1016/s0006-2952(01)00752-3] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
We recently demonstrated that severe thymic and splenic atrophy occur upon dietary treatment of mice with potent peroxisome proliferators (PPs), e.g. perfluorooctanoic acid (PFOA), WY-14,643, nafenopin, and di(2-ethylhexyl)phthalate (DEHP). In the present study, we investigated this phenomenon further employing a relative inert PP, PFOA. Comparison of the dose-dependencies and time-courses indicated that the peroxisome proliferative effect occurred prior to atrophy of both the thymus and spleen. However, following withdrawal of PFOA from the diet, the weight of the thymus and spleen rapidly returned to normal within 10 and 5 days, respectively, in contrast to the more persistent peroxisome proliferation. Furthermore, the changes in thymus and spleen weight upon PFOA treatment and the following withdrawal from diet paralleled the changes in total thymocyte and splenocyte counts, respectively. It was found previously that the decreases in the thymocyte populations present in the S and G2/M phases, as well as in the number of CD4+CD8+ cells upon PFOA treatment, were the most dramatic, perhaps reflecting inhibition of thymocyte proliferation in connection with thymocyte development. Here, the recovery of thymocytes began with increases in the populations in these same phases of the cell cycle, with CD4+CD8+ cells recovering most rapidly, lending further support to our previous hypothesis. The possible relationship of these immunotoxic effects of PPs to the changes they cause in fatty acid metabolism is discussed.
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Affiliation(s)
- Q Yang
- Unit for Biochemical Toxicology, Department of Biochemistry & Biophysics, Wallenberg Laboratory, Stockholm University, S-106 91, Stockholm, Sweden.
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20
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Myers LP, Krieg AM, Pruett SB. Bacterial DNA does not increase serum corticosterone concentration or prevent increases induced by other stimuli. Int Immunopharmacol 2001; 1:1605-14. [PMID: 11515823 DOI: 10.1016/s1567-5769(01)00075-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Bacterial DNA containing unmethylated CpG motifs (CpG DNA) and other microbial molecules such as lipopolysaccharide (LPS) have a broad range of immune stimulatory effects, which may include many shared cell signaling pathways leading to enhanced cytokine production. Some cytokines activate the hypothalamic-pituitary-adrenal (HPA) axis, and their production is downregulated by products of the HPA axis (glucocorticoids). Because such interactions have practical implications in the clinical use of CpG DNA, the present study was done to examine the effects of CpG DNA and LPS on serum corticosterone concentrations. In contrast to LPS, administration of CpG DNA (DNA from Escherichia coli) (30-300 microg) alone did not significantly increase serum corticosterone concentrations 1 or 4 h after administration. Administration of CpG DNA to mice prior to LPS caused a synergistic increase in serum tumor necrosis factor-alpha (TNF-alpha), indicative of an immune stimulatory effect. LPS and TNF-alpha, however, induced similar levels of corticosterone with or without concomitant CpG DNA. Increasing doses of LPS caused peak corticosterone levels similar to those induced by LPS in combination with CpG DNA. Exogenous TNF-alpha administered in vivo induced comparable concentrations of corticosterone with or without CpG DNA. An alternative stressor (restraint) yielded similar levels of corticosterone with or without CpG DNA. These results indicate that CpG DNA does not induce corticosterone release or alter its release by other stimuli, indicating biologically important differences in its immune effect compared to those of LPS, and possibly reduced toxicity.
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Affiliation(s)
- L P Myers
- Department of Cellular Biology and Anatomy, Louisiana State University Health Sciences Center, Shreveport 71130, USA
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21
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Abstract
Recent studies indicate that neuroendocrine-immune interactions can cause sufficient immunosuppression to adversely affect human health, but quantitative relationships between stress-related hormones or neurotransmitters and immune function have not been well documented. The mechanisms of stress-induced immunomodulation cannot be fully understood solely by identifying the hormones, neurotransmitters, and cytokines involved. Quantitative relationships and interactions must also be understood. Depending on the nature and duration of the stressor and the immunological parameter under investigation, stress responses can enhance, have no effect, or suppress immunological parameters. These quantitative relationships have implications with regard to safety assessment of drugs and chemicals and with regard to potential development of pharmacological interventions to ameliorate some of the immunosuppressive effects of stress. This review describes selected studies that relate the quantity and duration of exposure to stress-related neuroendocrine mediators to modulation of the immune system. These studies provide a useful starting point, but they also illustrate how much work remains to achieve a fully integrated qualitative and quantitative understanding of stress-induced immunomodulation.
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Affiliation(s)
- S B Pruett
- Department of Cellular Biology and Anatomy, Louisiana State University Health Sciences Center, 1501 Kings Highway, Shreveport, LA 71130, USA.
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22
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Marino AA, Wolcott RM, Chervenak R, Jourd'heuil F, Nilsen E, Frilot C, Pruett SB. Coincident nonlinear changes in the endocrine and immune systems due to low-frequency magnetic fields. Neuroimmunomodulation 2001; 9:65-77. [PMID: 11549888 DOI: 10.1159/000049009] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVE The characteristic biological effects of low-frequency electromagnetic fields (EMFs) appear to be functional changes in the central nervous, endocrine and immune systems. For unapparent reasons, however, the results of similar studies have often differed markedly from one another. We recognized that it had generally been assumed, in the studies, that EMF effects would exhibit a dose-effect relationship, which is a basic property of linear systems. Prompted by recent developments in the theory on nonlinear systems, we hypothesized that there was a nonlinear relationship between EMFs and the effects they produced in the endocrine and immune systems. METHODS We developed a novel analytical method that could be used to distinguish between linear and nonlinear effects, and we employed it to examine the effect of EMFs on the endocrine and immune systems. RESULTS Mice exposed to 5 G, 60 Hz for 1-175 days in 7 independent experiments reliably exhibited changes in serum corticosterone and lymphoid phenotype when the data were analyzed while allowing that the field exposure and the resulting effects could be nonlinearly related. When the analysis was restricted to linear relationships, no effects due to the field were found. CONCLUSIONS The results indicated that transduction of EMFs resulted in changes in both the endocrine and immune systems, and that the laws governing the changes in each system were not the type that govern conventional dose-effect relationships. Evidence based on mathematical modeling was found suggesting that the coincident changes could have been causally related.
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Affiliation(s)
- A A Marino
- Department of Orthopaedic Surgery, LSU Health Sciences Center, Shreveport, LA 71130-3932, USA.
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Pruett SB, Fan R, Myers LP, Wu WJ, Collier S. Quantitative analysis of the neuroendocrine-immune axis: linear modeling of the effects of exogenous corticosterone and restraint stress on lymphocyte subpopulations in the spleen and thymus in female B6C3F1 mice. Brain Behav Immun 2000; 14:270-87. [PMID: 11120596 DOI: 10.1006/brbi.2000.0605] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The effects of exogenous corticosterone and restraint stress on the number and percentage of lymphocyte subpopulations in the spleen and thymus were evaluated. The data were used to generate linear models that describe the relationship between these parameters and the area under the corticosterone concentration vs time curve (AUC). Comparison of the models revealed that the number of nucleated cells in the spleen was decreased similarly by exogenous corticosterone and restraint (at equivalent corticosterone AUC values). However, exogenous corticosterone caused a greater decrease in cell number in the thymus than it did in the spleen. Corticosterone preferentially depleted CD4+CD8+ cells in the thymus, whereas the same corticosterone exposure produced by restraint stress did not. In the spleen, cell number for all major cell types was decreased by both treatments, but there were minor differences in the change in percentage of some subpopulations induced by exogenous corticosterone as compared to restraint. The models derived here provide quantitative data that indicate the magnitude of corticosterone and stress-induced effects on lymphocyte populations in the spleen and thymus. These results have mechanistic implications, and they may be useful in future efforts to extrapolate from mouse to human by completing a risk assessment parallelogram.
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Affiliation(s)
- S B Pruett
- Department of Cellular Biology and Anatomy, Louisiana State University Health Sciences Center, Shreveport, Louisiana 71130, USA
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24
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Sepúlveda RT, Jiang S, Beischel J, Bellamy WT, Watson RR. Cocaine injection and coxsackievirus B3 infection increase heart disease during murine AIDS. J Acquir Immune Defic Syndr 2000; 25 Suppl 1:S19-26. [PMID: 11126422 DOI: 10.1097/00042560-200010001-00004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Coxsackievirus initiates myocarditis especially in the immunologically deficient or immature. To test whether Coxsackievirus B3 (CVB3) induced pronounced cardiomyopathy during severe immune dysfunction of murine AIDS, female C57BL/6 mice were infected with LP-BM5 retrovirus and superinfected with CVB3. Some were also injected daily with cocaine hydrochloride in 0.9% saline solution (30 mg/kg) intraperitoneally, because cocaine also suppresses cellular immune response. Heart tissue was analyzed histopathologically. Mice experiencing concurrent retrovirus and Coxsackievirus infection had a high degree of cardiac lesions consistent with myopathy compared with findings in uninfected animals (p <.05). Cocaine injection during murine retrovirus infection greatly exacerbated the pathogenesis of Coxsackievirus infection. C57BL/6 mice, essentially resistant to Coxsackievirus-induced cardiomyopathy, became susceptible during the immune dysfunction in murine AIDS. This suggests that retrovirus infection causes conditions favoring Coxsackie-induced cardiac lesions. Interleukin (IL)-2 and IL-4 expression by splenocytes from the dually infected retrovirus and Coxsackievirus group showed no significant differences when the animals were also cocaine treated. However tumor necrosis factor TNF-alpha production was significantly decreased in dually infected retrovirus + Coxsackievirus mice treated with cocaine, compared with findings in various controls (p <.05).
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Affiliation(s)
- R T Sepúlveda
- Arizona Prevention Center, University of Arizona, Tucson 85724, USA.
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25
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Cocaine Injection and Coxsackievirus B3 Infection Increase Heart Disease During Murine AIDS. J Acquir Immune Defic Syndr 2000. [DOI: 10.1097/00126334-200010001-00004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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26
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Cheema ZF, West JR, Miranda RC. Ethanol Induces Fas/Apo [Apoptosis]-1 mRNA and Cell Suicide in the Developing Cerebral Cortex. Alcohol Clin Exp Res 2000. [DOI: 10.1111/j.1530-0277.2000.tb02022.x] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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27
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Padgett EL, Sibley DA, Jerrells TR. Effect of adrenalectomy on ethanol-associated changes in lymphocyte cell numbers and subpopulations in thymus, spleen, and gut-associated lymphoid tissues. INTERNATIONAL JOURNAL OF IMMUNOPHARMACOLOGY 2000; 22:285-98. [PMID: 10689102 DOI: 10.1016/s0192-0561(99)00083-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Consumption of ethanol (ETOH) by experimental animals and human beings is associated with elevated serum levels of corticosteroids. One of the most robust findings associated with ETOH consumption is a loss of lymphocytes from thymus and spleen, as well as from peripheral lymphoid organs to include mesenteric lymph nodes and Peyer's patches, which are lymphoid organs associated with the gastrointestinal tract. To study the role of corticosteroids in loss of cells from thymus, spleen, and gut-associated lymphoid organs, adrenalectomized (ADX) or intact C57Bl/6 mice were fed a liquid diet containing ETOH (to supply 36% of calories as ETOH) or an isocaloric control diet with a pair-feeding protocol. Loss of lymphocytes from all lymphoid organs was associated closely with serum corticosterone levels in both ETOH-fed and pair-fed groups. ETOH-fed ADX animals showed much less cell loss than did ETOH-fed intact animals. However, there was still an association between ETOH consumption and cell loss when cell loss in ETOH-fed ADX animals was compared with that in ADX pair-fed and ADX chow-fed groups. In both intact and ADX animals ETOH consumption was associated with a loss of immature (CD4(+) and CD8(+)) cells from the thymus. These data lead to the suggestion that corticosteroids are responsible for most of the cell loss from thymus, spleen, mesenteric lymph nodes, and Peyer's patches in association with ETOH consumption. Some cell loss, however, is independent of corticosteroids. The data presented here also support the suggestion that cell loss from lymphoid organs could be the result of nutritional factors.
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Affiliation(s)
- E L Padgett
- Department of Cellular Biology and Anatomy, Louisiana State University Medical Center, Shreveport 71130, USA
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Collier SD, Wu WJ, Pruett SB. Ethanol Suppresses NK Cell Activation by Polyinosinic-Polycytidylic Acid (Poly I:C) in Female B6C3F1 Mice: Role of Endogenous Corticosterone. Alcohol Clin Exp Res 2000. [DOI: 10.1111/j.1530-0277.2000.tb04610.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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29
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Pruett SB, Collier SD, Wu WJ. Ethanol-induced activation of the hypothalamic-pituitary-adrenal axis in a mouse model for binge drinking: role of Ro15-4513-sensitive gamma aminobutyric acid receptors, tolerance, and relevance to humans. Life Sci 1998; 63:1137-46. [PMID: 9763209 DOI: 10.1016/s0024-3205(98)00375-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
A mouse model for binge drinking has been developed in this laboratory, and several aspects of this model have been characterized. Many of the immunosuppressive effects of ethanol (EtOH) in this model seem to be mediated by activation of the hypothalamic-pituitary-adrenal (HPA) axis and consequent increases in the concentration of glucocorticoids, catecholamines, and perhaps other immunosuppressive mediators. The purpose of the work described here is to examine three important issues regarding the EtOH-induced neuroendocrine response in this model: 1) Are Ro15-4513-sensitive gamma aminobutyric acid type A (GABA-A) receptors involved in activation of the HPA axis by EtOH? 2) Does daily administration of EtOH produce tolerance with regard to activation of the HPA axis or with regard to suppression of natural killer cell activity? 3) Is the HPA axis activated by similar blood EtOH concentrations in humans and in the mouse model? Ro15-4513, a partial inverse agonist of GABA-A receptors, did not affect EtOH-induced increases in blood corticosterone levels. This suggests that Ro15-4513-sensitive GABA-A receptors are not involved in EtOH-induced activation of the HPA axis and that inhibition of corticosterone production is not the mechanism by which Ro-15-4513 blocks EtOH-induced immunosuppression. To evaluate tolerance, mice were given a daily dose of EtOH (6.5 g/kg by gavage) or vehicle (water) for 10 days. Control groups received vehicle or EtOH only on the last day of the experiment. At the optimum time after EtOH administration serum corticosterone and splenic NK cell activity were measured. The results indicate no significant alterations in the response to EtOH of mice exposed to EtOH for 10 days compared to those exposed only once. To compare the HPA axis response of mice and humans, lower EtOH dosages than generally used in our model were administered to mice, and the corticosterone response was compared to published data for humans who had similar ranges of blood EtOH levels. The results suggest that humans and mice exhibit activation of the HPA axis only when blood EtOH levels exceed approximately 0.14%. Together these results further characterize a mouse model for binge drinking that seems to provide a reasonable representation of many aspects of binge drinking in humans.
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Affiliation(s)
- S B Pruett
- Department of Biological Sciences, Mississippi State University, MS 39762, USA.
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Vinson RB, Carroll JL, Pruett SB. Mechanism of suppressed neutrophil mobilization in a mouse model for binge drinking: role of glucocorticoids. THE AMERICAN JOURNAL OF PHYSIOLOGY 1998; 275:R1049-57. [PMID: 9756533 DOI: 10.1152/ajpregu.1998.275.4.r1049] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The goals of this study were to determine if suppression of neutrophil accumulation and TNF-alpha production in the peritoneal cavity occurs in mice exposed to a chemical stressor [ethanol (EtOH)], to evaluate the role of EtOH-induced increases in endogenous glucocorticoids in any such suppression, and to determine if decreased tumor necrosis factor-alpha (TNF-alpha) production is responsible for decreases in neutrophil accumulation in EtOH-treated mice. An inflammatory response induced in the peritoneal cavity of mice by administration of heat-killed Propionibacterium acnes (P. acnes) was suppressed by a single dose of EtOH given 1 h before administration of the bacteria, as indicated by decreased accumulation of neutrophils in the peritoneal cavity. The concentration of TNF-alpha in the peritoneal cavity was also decreased by EtOH, but exogenous TNF-alpha did not prevent the suppression of neutrophil accumulation. The glucocorticoid antagonist RU-486 did not prevent the suppression of neutrophil accumulation in mice treated with EtOH, but RU-486 did block suppression of neutrophil accumulation caused by administration of exogenous corticosterone. The suppression of neutrophil accumulation caused by exogenous corticosterone was less than produced by EtOH. These observations suggest that the increase in endogenous corticosterone induced by EtOH may explain some of the suppression of neutrophil accumulation, but other neuroendocrine mediators (or EtOH per se) are sufficient to cause the full suppressive effect when the action of corticosterone is blocked by RU-486. The results also demonstrate that EtOH decreases TNF-alpha production, but this is not the mechanism by which neutrophil accumulation is decreased in this model.
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Affiliation(s)
- R B Vinson
- Department of Biological Sciences, Mississippi State University, Mississippi State, Mississippi 39762, USA
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Morishita S, Sato EF, Takahashi K, Manabe M, Inoue M. Insulin-induced hypoglycemia elicits thymocyte apoptosis in the rat. Diabetes Res Clin Pract 1998; 40:1-7. [PMID: 9699084 DOI: 10.1016/s0168-8227(98)00013-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Although various types of stress induce thymus atrophy and suppress immune functions, the mechanisms involved are unknown. To test the hypothesis that thymocyte apoptosis plays a role in stress-induced atrophy of the thymus, we studied the effects of starvation and hypoglycemia on the thymus in the rat. Administration of insulin caused marked hypoglycemia, increased the plasma corticosterone level, and induced fragmentation of thymocyte DNA in fasted but not in fed rats. Administration of either glucose or RU486, a glucocorticoid receptor antagonist, inhibited the apoptosis of thymocytes elicited by insulin. Available evidence suggest that insulin-induced hypoglycemia causes thymocyte apoptosis by promoting glucocorticoid secretion from the adrenal gland.
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Affiliation(s)
- S Morishita
- Department of Biochemistry, Osaka City University Medical School, Japan
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San Gil F, Turner B, Mullbacher A, Walker MJ, Djordjevic SP, Eamens GJ, Chin JC. Flow cytometric analysis of cellular changes in mice after intradermal inoculation with a liposome-iscom adjuvanted vaccine. Scand J Immunol 1998; 47:243-53. [PMID: 9519863 DOI: 10.1046/j.1365-3083.1998.00304.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
As it is not known what changes to leucocyte homeostasis are mandatory for effective adjuvant action, the biological relevance of systemic changes elicited by different vaccine formulations can only be interpreted in the context of the immunological outcomes. We used flow cytometry to quantify the changes in leucocyte subsets induced in mice intradermally immunized with SAMA4 (adjuvant group), outer membrane proteins (OMP) purified from Actinobacillus pleuropneumoniae (OMP antigen group), SAMA4 adjuvanted OMP (OMP vaccine group), or phosphate-buffered saline (PBS: control group). This approach allowed direct comparisons to be made between the effects of antigen, adjuvant or antigen-adjuvant complexes on immune effector cell populations. Antigens complexed with the liposome-iscom hybrid adjuvant, SAMA4, generated strong antibody responses and cytotoxic T-cell activity in animals immunized intradermally, reflecting remobilization and recruitment of specific cell populations. Splenomegaly, due to granulocytosis, monocytosis and megakaryocytosis, was most prominent in the OMP vaccine group. Histological examination of spleen sections confirmed that these changes were due primarily to splenic haematopoiesis. Circulating numbers of granulocytes and monocytes increased significantly (P < 0.05) in the blood of the OMP vaccine group, as did granulocyte numbers in the lungs (P < 0.05). No changes in T- and B-cell numbers were detected by flow cytometry in the spleens, lungs or blood over the 28-day period in any treatment group. Thymocyte numbers (predominantly CD4+CD8+ cells) in the OMP vaccine group fell by 95% within 3 days of immunization. Identical cellular responses were obtained when an innocuous antigen, ovalbumin, was complexed with SAMA4 instead of OMP, thus demonstrating that the adjuvant effects of SAMA4 were due to synergistic interaction between antigen and adjuvant and not due to the presence of toxic components. The association of strong adaptive immune responses with such complex changes in leucocyte homeostasis induced by complexing adjuvant and antigen suggested that the changes were important for effective vaccination and were not purely circumstantial.
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Affiliation(s)
- F San Gil
- NSW Agriculture, Elizabeth Macarthur Agricultural Institute, Camden, Australia
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Weiss PA, Collier SD, Pruett SB. Effect of ethanol on B cell expression of major histocompatibility class II proteins in immunized mice. IMMUNOPHARMACOLOGY 1998; 39:61-72. [PMID: 9667424 DOI: 10.1016/s0162-3109(97)00099-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Acute or chronic exposure to ethanol (EtOH), as well as other stimuli that induce a neuroendocrine stress response, can decrease the expression of MHC class II proteins (immune-associated antigens, Ia) on B cells and macrophages. In a mouse model for binge drinking, it has been shown that this decrease is caused by EtOH-induced increases in endogenous glucocorticoids. Decreased Ia expression would be expected to suppress T-dependent humoral responses, and such suppression has been noted in our model. However, it has been reported that activated B cells are much less susceptible to glucocorticoid-induced decreases in Ia expression than are resting B cells. Thus, it is not clear that the decreased Ia observed in our previous studies with non-immunized mice could account for decreased humoral responses, because it has not been directly determined that decreased Ia expression occurs in immunized mice. To examine this issue, splenocytes from mice immunized with sheep erythrocytes were studied by flow cytometry. Mice were treated with EtOH by gavage and immunized 12 h later, because our previous results indicate that this produces maximal suppression of the humoral response. In immunized mice, EtOH decreased Ia expression on B cells at 6 and 12 h after immunization, but not at 24 or 74 h. In a dose-response study, a substantial decrease in Ia expression on B cells was observed at an EtOH dosage of 6.0 or 7.0 g/kg. Thus, decreased Ia expression is a potential mechanism for EtOH-induced suppression of the humoral response. A glucocorticoid antagonist (RU 486) partially blocked the EtOH-induced decrease in Ia expression, suggesting that glucocorticoids are involved in the reduction of Ia expression in immunized mice. Direct administration of corticosterone to produce blood levels comparable to those noted in EtOH-treated mice did not significantly decrease Ia expression, but Ia expression tended to be lower in mice treated with corticosterone. Taken together, these results indicate that glucocorticoids play some role in decreasing Ia expression in immunized mice, but they are less important than in non-immunized mice.
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Affiliation(s)
- P A Weiss
- Department of Biological Sciences, Mississippi State University, Mississippi 39762, USA
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Collier SD, Wu WJ, Pruett SB. Endogenous glucocorticoids induced by a chemical stressor (ethanol) cause apoptosis in the spleen in B6C3F1 female mice. Toxicol Appl Pharmacol 1998; 148:176-82. [PMID: 9465277 DOI: 10.1006/taap.1997.8324] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Stress-induced increases in glucocorticoid levels can cause-apoptosis in immature thymocytes, but it is not known if glucocorticoids at these levels can also cause apoptosis in peripheral lymphocytes. In the present study, mice were exposed to ethanol (EtOH) in a model designed to represent binge drinking. This induces a substantial stress response, including an increase in corticosterone levels. Apoptosis in the spleen was evaluated using terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) with fluorescein-labeled dUTP. Flow cytometric analysis demonstrated a significant increase in the percentage of apoptotic cells in the spleen 2-6 h after administration of EtOH (3-6% apoptotic cells in treated mice vs 0.2-2% in controls). This increase was blocked by the glucocorticoid antagonist, RU 486, and administration of exogenous corticosterone in a manner that produced similar blood levels and kinetics as noted in EtOH-treated mice produced similar levels of apoptosis. Fluorescein-labeled Annexin V was used to confirm increased numbers of apoptotic cells in the spleen in EtOH-treated mice. These results indicate that stress-induced glucocorticoids are sufficient to induce apoptosis in the spleen, and this may be one mechanism by which stress responses cause immunosuppression.
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Affiliation(s)
- S D Collier
- Department of Biological Sciences, Mississippi State University, Mississippi State 39762, USA
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Wu WJ, Pruett SB. Involvement of Catecholamines and Glucocorticoids in Ethanol-Induced Suppression of Splenic Natural Killer Cell Activity in a Mouse Model for Binge Drinking. Alcohol Clin Exp Res 1997. [DOI: 10.1111/j.1530-0277.1997.tb04249.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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De Waal EJ, Schuurman HJ, Van Loveren H, Vos JG. Differential effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin, bis(tri-n-butyltin) oxide and cyclosporine on thymus histophysiology. Crit Rev Toxicol 1997; 27:381-430. [PMID: 9263645 DOI: 10.3109/10408449709089900] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Recent advances in the histophysiology of the normal thymus have revealed its complex architecture, showing distinct microenvironments at the light and electron microscopic level. The epithelium comprising the major component of the thymic stroma is not only involved in the positive selection of thymocytes, but also in their negative selection. Dendritic cells, however, are more efficient than epithelial cells in mediating negative selection. Thymocytes are dependent on the epithelium for normal development. Conversely, epithelial cells need the presence of thymocytes to maintain their integrity. The thymus rapidly responds to immunotoxic injury. Both the thymocytes and the nonlymphoid compartment of the organ can be targets of exposure. Disturbance of positive and negative thymocyte selection may have a major impact on the immunological function of the thymus. Suppression of peripheral T-cell-dependent immunity as a consequence of thymus toxicity is primarily seen after perinatal exposure when the thymus is most active. Autoimmunity may be another manifestation of chemically mediated thymus toxicity. Although the regenerative capacity of thymus structure is remarkable, it remains to be clarified whether this also applies to thymus function. In-depth mechanistic studies on chemical-induced dysfunction of the thymus have been conducted with the environmental contaminants 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and bis(tri-n-butyltin)oxide (TBTO) as well as the pharmaceutical immunosuppressant cyclosporine (CsA). Each of these compounds exerts a differential effect on the morphology of the thymus, depending on the cellular targets for toxicity. TCDD and TBTO exposure results in cortical lymphodepletion, albeit by different mechanisms. An important feature of TCDD-mediated thymus toxicity is the disruption of epithelial cells in the cortex. TBTO primarily induces cortical thymocyte cell death. In contrast CsA administration results in major alterations in the medulla, the cortex remaining largely intact. Medullary epithelial cells and dendritic cells are particularly sensitive to CsA. The differential effects of these three immunotoxicants suggest unique susceptibilities of the various cell types and regions that make up the thymus.
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Affiliation(s)
- E J De Waal
- Laboratory for Medicines and Medical Devices, National Institute of Public Health, Bilthoven, The Netherlands
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37
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Abstract
This study examines the effects of chronic alcohol consumption on thymic apoptosis with or without pretreatment with E. coli lipopolysaccharide (LPS). Apoptotic cell death of thymocytes was monitored by DNA fragments in gel electrophoresis and the appearance of apoptotic cells by flow cytometry. Changes in mitochondrial membrane potential (MMP), as indicated by 3,3'-dihexyloxacarbocyanine iodide [DiOC6(3)] uptake, and hydrogen peroxide (H2O2) production as indicated by oxidation of 2',7'-dichlorofluresin diacetate (DCFH-DA), were used to assess altered mitochondrial function. Glutathione levels were also determined to obtain information concerning alterations in the antioxidant potential in the cells. Male Sprague-Dawley rats, fed a nutritionally adequate liquid diet for 8-9 weeks, were divided in four groups: 1) saline-injected, diet controls; 2) LPS-injected, diet controls; 3) saline-injected, alcohol-consuming; and 4) LPS-injected, alcohol-consuming animals. LPS (0.5 mg/kg in 4 ml saline) or saline (4 ml) was continuously infused i.v. for 12 h before the experiments. The results showed that the weight and cell numbers of thymus from the chronic alcoholic rats were significantly less than values found in diet controls. Administration of LPS aggravated thymic apoptosis, as indicated by the presence of significant DNA fragments in gel electrophoresis and increased rate of apoptotic cells in flow cytometry. The alcohol-induced apoptotic changes were also accompanied by decreased MMP, indicating impaired mitochondrial function. Although H2O2 production by the total thymocyte population did not show marked changes among the experimental groups, the subpopulation of thymocytes exhibiting low H2O2 production was increased markedly in the LPS-treated groups. Ethanol consumption or LPS treatment decreased total glutathione concentration in the thymocytes. In summary, 1) chronic administration of alcohol induces atrophy of the thymus gland; 2) apoptosis is a major factor in thymic atrophy under these conditions; 3) chronic alcohol consumption is accompanied by alterations in mitochondrial function of the thymocytes, as indicated by decreased MMP and an increase in the low H2O2-producing cell subpopulation; 4) chronic alcohol abuse may impair intracellular defense mechanisms as reflected by the depletion of the intracellular antioxidant, glutathione; and 5) administration of LPS further enhances thymic apoptosis in chronic alcohol-consuming rats, suggesting that the dual insults of infection and chronic alcoholism exaggerate in vivo immunosuppression.
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Affiliation(s)
- J F Wang
- Department of Physiology, Louisiana State University Medical Center, New Orleans 70112, USA
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Carson EJ, Pruett SB. Development and characterization of a binge drinking model in mice for evaluation of the immunological effects of ethanol. Alcohol Clin Exp Res 1996; 20:132-8. [PMID: 8651442 DOI: 10.1111/j.1530-0277.1996.tb01055.x] [Citation(s) in RCA: 130] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
This study describes the development and characterization of a binge drinking model in which a single dose of ethanol (EtOH) is administered by gavage to B6C3F1 mice. Blood EtOH levels were monitored over time after administration of EtOH at doses of 3.0-7.0 g/kg. Peak levels were in the range of 0.2-0.5%, and clearance was complete within 2-12 hr. Substantial increases in blood corticosterone levels were noted. Behavioral changes in EtOH-treated mice aged 8 weeks ranged from no effect (3-4 g/kg) to severe ataxia (6-7 g/kg). In mice aged 16 weeks, a dosage of 7 g/kg caused less of the righting reflex in some animals and severe ataxia in most of the others. Clinical chemistry results did not indicate biologically important changes in general physiological/homeostatic systems in EtOH-treated mice, but there were indications of minor liver damage at the 7 g/kg dosage. Thus, administration of EtOH to B6C3F1 mice by gavage produces behavioral changes, changes in blood EtOH levels, and probably glucocorticoid levels representative of at least some human binge drinkers. The model was used to evaluate the effects of binge drinking on antibody responses, and the results indicate the model will be useful for such studies.
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Affiliation(s)
- E J Carson
- Department of Biological Sciences, Mississippi State University, Mississippi State 39762, USA
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Abstract
Glucocorticoid hormones influence the physiological activity of almost all cell types in the mammal. This is accomplished via a soluble receptor that, in the presence of an appropriate steroid, modifies the activity of RNA polymerase by binding to the site where different factors assemble for the initiation of cell transcription. The development of antiglucocorticoids has permitted the molecular elucidation of a number of underlying events. Contrary to the classical view, it is now clear that the affinity, stability and activability of the glucocorticoid receptor in the presence of a steroid are cell- and/or tissue-dependent events. The antiglucocorticoid RU 38486 can even activate transcription by binding to sites distinct from those that process transactivation by the agonist. Furthermore, glucocorticoids can sometimes activate the mineralocorticoid receptor, whereas mineralocorticoids can bind the glucocorticoid receptor. Since mifepristone is devoid of adverse toxicity, it has been used for the paraclinical diagnosis of the hypothalamus-pituitary-adrenal axis in normal volunteers, subjects with disorders of the behaviour, and the treatment of Cushing's disease. However, the whole spectrum of cell-specific processes that are antagonized by RU 38486 suggests wide ranging possibilities in the eventual application of antigluco-corticoids.
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Affiliation(s)
- M K Agarwai
- Hormone Laboratory, Centre Universitaire Des Cordeliers, Paris, France
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Braun KP, Pearce RB, Peterson CM. Acetaldehyde-serum protein adducts inhibit interleukin-2 secretion in concanavalin A-stimulated murine splenocytes: a potential common pathway for ethanol-induced immunomodulation. Alcohol Clin Exp Res 1995; 19:345-9. [PMID: 7625567 DOI: 10.1111/j.1530-0277.1995.tb01513.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Variable immunobiological changes occur with alcohol consumption. Previous studies have shown that acetaldehyde forms stable adducts with serum proteins, including albumin. These adducts are elevated in persons and animals consuming ethanol. We examined the effect of serum protein-acetaldehyde adducts formed with fetal bovine serum (FBS) on concanavalin A-stimulated murine splenocytes. Interleukin-2 (IL-2) secretion and IL-2 receptor (IL-2R) expression were determined as a function of the effect of the acetaldehyde-protein adduct(s). FBS was incubated with acetaldehyde (500, 100, 50, 25, 10, and 0 microM) for 1 hr at 37 degrees C. Excess acetaldehyde was removed by ultrafiltration using a 500 molecular weight cut-off membrane in 3 volumes. Free as well as bound acetaldehyde was quantified using fluorigenic HPLC before and after incubation. Recovered acetaldehyde correlated with the amount added (r2 = 0.996). Splenocytes were cultured for 48 hr in complete medium containing 5% acetaldehyde-treated and 5% untreated FBS with 4 micrograms/ml concanavalin A. Although cell viability was unchanged, acetaldehyde-treated FBS mixed with native FBS decreased IL-2 secretion in a dose-dependent manner. The percentage of cells expressing IL-2R was reduced only at the highest acetaldehyde-FBS dose. Therefore, immunological effects ascribed to ethanol may result in part from the toxic properties of acetaldehyde-protein adducts on IL-2 secretion.
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Affiliation(s)
- K P Braun
- Sansum Medical Research Foundation, Santa Barbara, California 93105, USA
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