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Isola JVV, Veiga GB, de Brito CRC, Alvarado-Rincón JA, Garcia DN, Zanini BM, Hense JD, Vieira AD, Garratt M, Gasperin BG, Schneider A, Stout MB. 17α-estradiol does not adversely affect sperm parameters or fertility in male mice: implications for reproduction-longevity trade-offs. GeroScience 2023; 45:2109-2120. [PMID: 35689785 PMCID: PMC10651587 DOI: 10.1007/s11357-022-00601-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Accepted: 06/04/2022] [Indexed: 11/30/2022] Open
Abstract
17α-estradiol (17α-E2) is referred to as a nonfeminizing estrogen that was recently found to extend healthspan and lifespan in male, but not female, mice. Despite an abundance of data indicating that 17α-E2 attenuates several hallmarks of aging in male rodents, very little is known with regard to its effects on feminization and fertility. In these studies, we evaluated the effects of 17α-E2 on several markers of male reproductive health in two independent cohorts of mice. In alignment with our previous reports, chronic 17α-E2 treatment prevented gains in body mass, but did not adversely affect testes mass or seminiferous tubule morphology. We subsequently determined that chronic 17α-E2 treatment also did not alter plasma 17β-estradiol or estrone concentrations, while mildly increasing plasma testosterone levels. We also determined that chronic 17α-E2 treatment did not alter plasma follicle-stimulating hormone or luteinizing hormone concentrations, which suggests 17α-E2 treatment does not alter gonadotropin-releasing hormone neuronal function. Sperm quantity, morphology, membrane integrity, and various motility measures were also unaffected by chronic 17α-E2 treatment in our studies. Lastly, two different approaches were used to evaluate male fertility in these studies. We found that chronic 17α-E2 treatment did not diminish the ability of male mice to impregnate female mice, or to generate successfully implanted embryos in the uterus. We conclude that chronic treatment with 17α-E2 at the dose most commonly employed in aging research does not adversely affect reproductive fitness in male mice, which suggests 17α-E2 does not extend lifespan or curtail disease parameters through tradeoff effects with reproduction.
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Affiliation(s)
- José V V Isola
- Aging & Metabolism Research Program, Oklahoma Medical Research Foundation, 825 NE 13th Street, Chapman S212, Oklahoma City, OK, 73104, USA
- Faculdade de Veterinária, Universidade Federal de Pelotas, Pelotas, RS, Brazil
| | - Gabriel B Veiga
- Faculdade de Nutrição, Universidade Federal de Pelotas, Rua Gomes Carneiro, 1, Pelotas, RS, 96010-610, Brazil
| | - Camila R C de Brito
- Faculdade de Veterinária, Universidade Federal de Pelotas, Pelotas, RS, Brazil
| | - Joao A Alvarado-Rincón
- Facultad de Ciencias Agropecuarias, Universidad de La Salle, Campus Utopía, Yopal, Casanare, Colombia
| | - Driele N Garcia
- Faculdade de Nutrição, Universidade Federal de Pelotas, Rua Gomes Carneiro, 1, Pelotas, RS, 96010-610, Brazil
| | - Bianka M Zanini
- Faculdade de Veterinária, Universidade Federal de Pelotas, Pelotas, RS, Brazil
| | - Jéssica D Hense
- Faculdade de Nutrição, Universidade Federal de Pelotas, Rua Gomes Carneiro, 1, Pelotas, RS, 96010-610, Brazil
| | - Arnaldo D Vieira
- Faculdade de Veterinária, Universidade Federal de Pelotas, Pelotas, RS, Brazil
| | - Michael Garratt
- Department of Anatomy, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
| | - Bernardo G Gasperin
- Faculdade de Veterinária, Universidade Federal de Pelotas, Pelotas, RS, Brazil
| | - Augusto Schneider
- Faculdade de Veterinária, Universidade Federal de Pelotas, Pelotas, RS, Brazil.
- Faculdade de Nutrição, Universidade Federal de Pelotas, Rua Gomes Carneiro, 1, Pelotas, RS, 96010-610, Brazil.
| | - Michael B Stout
- Aging & Metabolism Research Program, Oklahoma Medical Research Foundation, 825 NE 13th Street, Chapman S212, Oklahoma City, OK, 73104, USA.
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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: 13] [Impact Index Per Article: 3.3] [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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Epelbaum J, Terrien J. Mini-review: Aging of the neuroendocrine system: Insights from nonhuman primate models. Prog Neuropsychopharmacol Biol Psychiatry 2020; 100:109854. [PMID: 31891735 DOI: 10.1016/j.pnpbp.2019.109854] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Accepted: 12/27/2019] [Indexed: 01/29/2023]
Abstract
The neuroendocrine system (NES) plays a crucial role in synchronizing the physiology and behavior of the whole organism in response to environmental constraints. The NES consists of a hypothalamic-pituitary-target organ axis that acts in coordination to regulate growth, reproduction, stress and basal metabolism. The growth (or somatotropic), hypothalamic-pituitary-gonadal (HPG), hypothalamic-pituitary-adrenal (HPA) and hypothalamic-pituitary-thyroid (HPT) axes are therefore finely tuned by the hypothalamus through the successive release of hypothalamic and pituitary hormones to control the downstream physiological functions. These functions rely on a complex set of mechanisms requiring tight synchronization between peripheral organs and the hypothalamic-pituitary complex, whose functionality can be altered during aging. Here, we review the results of research on the effects of aging on the NES of nonhuman primate (NHP) species in wild and captive conditions. A focus on the age-related dysregulation of the master circadian pacemaker, which, in turn, alters the synchronization of the NES with the organism environment, is proposed. Finally, practical and ethical considerations of using NHP models to test the effects of nutrition-based or hormonal treatments to combat the deterioration of the NES are discussed.
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Affiliation(s)
- Jacques Epelbaum
- UMR CNRS/MNHN 7179, Mécanismes Adaptatifs et Evolution, 1 Avenue du Petit Château, 91800 Brunoy, France; Unité Mixte de Recherche en Santé 894 INSERM, Centre de Psychiatrie et Neurosciences, Université Paris Descartes, Sorbonne Paris Cité, 75014 Paris, France
| | - Jérémy Terrien
- UMR CNRS/MNHN 7179, Mécanismes Adaptatifs et Evolution, 1 Avenue du Petit Château, 91800 Brunoy, France.
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4
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Martins AD, Jarak I, Morais T, Carvalho RA, Oliveira PF, Monteiro MP, Alves MG. Caloric restriction alters the hormonal profile and testicular metabolome, resulting in alterations of sperm head morphology. Am J Physiol Endocrinol Metab 2020; 318:E33-E43. [PMID: 31770015 DOI: 10.1152/ajpendo.00355.2019] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Energy homeostasis is crucial for all physiological processes. Thus, when there is low energy intake, negative health effects may arise, including in reproductive function. We propose to study whether caloric restriction (CR) changes testicular metabolic profile and ultimately sperm quality. Male Wistar rats (n = 12) were randomized into a CR group fed with 30% fewer calories than weight-matched, ad libitum-fed animals (control group). Circulating hormonal profile, testicular glucagon-like peptide-1 (GLP-1), ghrelin and leptin receptors expression, and sperm parameters were analyzed. Testicular metabolite abundance and glycolysis-related enzymes were studied by NMR and Western blot, respectively. Oxidative stress markers were analyzed in testicular tissue and spermatozoa. Expressions of mitochondrial complexes and mitochondrial biogenesis in testes were determined. CR induced changes in body weight along with altered GLP-1, ghrelin, and leptin circulating levels. In testes, CR led to changes in receptor expression that followed those of the hormone levels; modified testicular metabolome, particularly amino acid content; and decreased oxidative stress-induced damage in testis and spermatozoa, although sperm head defects increased. In sum, CR induced changes in body weight, altering circulating hormonal profile and testicular metabolome and increasing sperm head defects. Ultimately, our data highlight that conditions of CR may compromise male fertility.
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Affiliation(s)
- Ana D Martins
- Department of Microscopy, Laboratory of Cell Biology, Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Porto, Portugal
- Unit for Multidisciplinary Research in Biomedicine, Institute of Biomedical Sciences Abel Salazar (UMIB-ICBAS), University of Porto, Porto, Portugal
| | - Ivana Jarak
- Department of Microscopy, Laboratory of Cell Biology, Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Porto, Portugal
- Unit for Multidisciplinary Research in Biomedicine, Institute of Biomedical Sciences Abel Salazar (UMIB-ICBAS), University of Porto, Porto, Portugal
| | - Tiago Morais
- Unit for Multidisciplinary Research in Biomedicine, Institute of Biomedical Sciences Abel Salazar (UMIB-ICBAS), University of Porto, Porto, Portugal
- Department of Anatomy, Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Porto, Portugal
| | - Rui A Carvalho
- Department of Life Sciences, University of Coimbra, Coimbra, Portugal
- REQUIMTE/LAQV, Group of Pharmaceutical Technology, Faculty of Pharmacy, University of Coimbra, Portugal
| | - Pedro F Oliveira
- Department of Microscopy, Laboratory of Cell Biology, Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Porto, Portugal
- Unit for Multidisciplinary Research in Biomedicine, Institute of Biomedical Sciences Abel Salazar (UMIB-ICBAS), University of Porto, Porto, Portugal
- Department of Genetics, Faculty of Medicine, University of Porto, Porto, Portugal
- i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
| | - Mariana P Monteiro
- Unit for Multidisciplinary Research in Biomedicine, Institute of Biomedical Sciences Abel Salazar (UMIB-ICBAS), University of Porto, Porto, Portugal
- Department of Anatomy, Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Porto, Portugal
- Obesity and Bariatric Services and Centre for Obesity Research, University College of London Hospitals, UCL, London, United Kingdom
| | - Marco G Alves
- Department of Microscopy, Laboratory of Cell Biology, Institute of Biomedical Sciences Abel Salazar (ICBAS), University of Porto, Porto, Portugal
- Unit for Multidisciplinary Research in Biomedicine, Institute of Biomedical Sciences Abel Salazar (UMIB-ICBAS), University of Porto, Porto, Portugal
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Balasubramanian P, Howell PR, Anderson RM. Aging and Caloric Restriction Research: A Biological Perspective With Translational Potential. EBioMedicine 2017; 21:37-44. [PMID: 28648985 PMCID: PMC5514430 DOI: 10.1016/j.ebiom.2017.06.015] [Citation(s) in RCA: 93] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Revised: 06/14/2017] [Accepted: 06/16/2017] [Indexed: 12/14/2022] Open
Abstract
Aging as a research pursuit is fairly new compared with traditional lines of medical research. A growing field of investigators is focused on understanding how changes in tissue biology, physiology, and systemic homeostasis, conspire to create increased vulnerability to disease as a function of age. Aging research as a discipline is necessarily broad; in part because aging itself is multi-faceted and in part because different model systems are employed to define the underlying biology. In this review we outline aspects of aging research that are likely to uncover the pivotal events leading to age-related disease vulnerability. We focus on studies of human aging and discuss the value of research on caloric restriction, an intervention with proven efficacy in delaying aging. We propose that studies such as these will deliver target factors and processes that create vulnerability in human aging, an advance that would potentially be transformative in clinical care.
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Affiliation(s)
- Priya Balasubramanian
- Department of Medicine, Division of Geriatrics and Gerontology, School of Medicine and Public Health, University of Wisconsin Madison, WI 53792, United States
| | - Porsha R Howell
- Department of Medicine, Division of Geriatrics and Gerontology, School of Medicine and Public Health, University of Wisconsin Madison, WI 53792, United States
| | - Rozalyn M Anderson
- Department of Medicine, Division of Geriatrics and Gerontology, School of Medicine and Public Health, University of Wisconsin Madison, WI 53792, United States; Geriatric Research, Education, and Clinical Center, William S. Middleton Memorial Veterans Hospital, Madison, WI 53705, United States.
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Comparative Proteomics of Activated THP-1 Cells Infected with Mycobacterium tuberculosis Identifies Putative Clearance Biomarkers for Tuberculosis Treatment. PLoS One 2015. [PMID: 26214306 PMCID: PMC4516286 DOI: 10.1371/journal.pone.0134168] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Biomarkers for determining clearance of Mycobacterium tuberculosis (Mtb) infection during anti-tuberculosis therapy or following exposure could facilitate enhanced monitoring and treatment. We screened for biomarkers indicating clearance of Mtb infection in vitro. A comparative proteomic analysis was performed using GeLC MSI/MS. Intracellular and secreted proteomes from activated THP-1 cells infected with the Mtb H37Rv strain (MOI = 1) and treated with isoniazid and rifampicin for 1 day (infection stage) and 5 days (clearance stage) were analyzed. Host proteins associated with early infection (n = 82), clearance (n = 121), sustained in both conditions (n = 34) and suppressed by infection (n = 46) were elucidated. Of the potential clearance markers, SSFA2 and CAECAM18 showed the highest and lowest protein intensities, respectively. A western blot of CAECAM18 validated the LC MS/MS result. For three clearance markers (SSFA2, PARP14 and PSME4), in vivo clinical validation was concordantly reported in previous patient cohorts. A network analysis revealed that clearance markers were enriched amongst four protein interaction networks centered on: (i) CD44/CCND1, (ii) IFN-β1/NF-κB, (iii) TP53/TGF-β and (iv) IFN-γ/CCL2. After infection, proteins associated with proliferation, and recruitment of immune cells appeared to be enriched possibly reflecting recruitment of defense mechanisms. Counteracting proteins (CASP3 vs. Akt and NF-κB vs. TP53) associated with apoptosis regulation and its networks were enriched among the early and sustained infection biomarkers, indicating host-pathogen competition. The BRCA1/2 network was suppressed during infection, suggesting that cell proliferation suppression is a feature of Mtb survival. Our study provides insights into the mechanisms of host-Mtb interaction by comparing the stages of infection clearance. The identified clearance biomarkers may be useful in monitoring tuberculosis treatment.
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7
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Sitzmann BD, Brown DI, Garyfallou VT, Kohama SG, Mattison JA, Ingram DK, Roth GS, Ottinger MA, Urbanski HF. Impact of moderate calorie restriction on testicular morphology and endocrine function in adult rhesus macaques (Macaca mulatta). AGE (DORDRECHT, NETHERLANDS) 2014; 36:183-197. [PMID: 23881606 PMCID: PMC3889886 DOI: 10.1007/s11357-013-9563-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Accepted: 07/01/2013] [Indexed: 06/02/2023]
Abstract
We previously reported that moderate calorie restriction (CR) has minimal impact on testicular gene expression in young adult rhesus macaques, and no obvious negative impact on semen quality or plasma testosterone levels. We now extend these findings by examining the influence of CR on various aspects of the reproductive axis of older males, including 24-h circulating testosterone levels, testicular gene expression, and testicular morphology. Young adult and old adult male rhesus macaques were subjected to either 30 % CR for 5-7 years, or were fed a standard control diet. Analysis of the 24-h plasma testosterone profiles revealed a significant age-associated decline, but no evidence for CR-induced suppression in either the young or old males. Similarly, expression profiling of key genes associated with testosterone biosynthesis and Leydig cell maintenance showed no significant CR-induced changes in either the young or old animals. The only evidence for CR-associated negative effects on the testis was detected in the old animals at the histological level; when old CR animals were compared with their age-matched controls, there was a modest decrease in seminiferous tubule diameter and epithelium height, with a concomitant increase in the number of depleted germ cell lines. Reassuringly, data from this study and our previous study suggest that moderate CR does not negatively impact 24-h plasma testosterone profiles or testicular gene expression. Although there appear to be some minor CR-induced effects on testicular morphology in old animals, it is unclear if these would significantly compromise fertility.
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Affiliation(s)
- Brandon D. Sitzmann
- />Division of Neuroscience, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR 97006 USA
- />Department of Animal and Avian Sciences, University of Maryland, College Park, MD 20742 USA
| | - Donald I. Brown
- />Division of Neuroscience, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR 97006 USA
- />Departamento de Biología y Ciencias Ambientales, Facultad Ciencias, Universidad de Valparaíso, Gran Bretaña 1111, Playa Ancha, Valparaíso, Chile
| | - Vasilios T. Garyfallou
- />Division of Neuroscience, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR 97006 USA
| | - Steven G. Kohama
- />Division of Neuroscience, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR 97006 USA
| | - Julie A. Mattison
- />National Institute on Aging, National Institutes of Health, Translational Gerontology Branch, Baltimore, MD 21224 USA
| | - Donald K. Ingram
- />National Institute on Aging, National Institutes of Health, Translational Gerontology Branch, Baltimore, MD 21224 USA
- />Nutritional Neuroscience and Aging Laboratory, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA 70808 USA
| | | | - Mary Ann Ottinger
- />Department of Animal and Avian Sciences, University of Maryland, College Park, MD 20742 USA
| | - Henryk F. Urbanski
- />Division of Neuroscience, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR 97006 USA
- />Department of Reproductive and Developmental Sciences, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR 97006 USA
- />Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, OR 97239 USA
- />Department of Physiology and Pharmacology, Oregon Health and Science University, Portland, OR 97239 USA
- />Division of Neuroscience, ONPRC, 505 NW 185th Avenue, Beaverton, OR 97006 USA
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Everds NE, Snyder PW, Bailey KL, Bolon B, Creasy DM, Foley GL, Rosol TJ, Sellers T. Interpreting Stress Responses during Routine Toxicity Studies. Toxicol Pathol 2013; 41:560-614. [DOI: 10.1177/0192623312466452] [Citation(s) in RCA: 201] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Stress often occurs during toxicity studies. The perception of sensory stimuli as stressful primarily results in catecholamine release and activation of the hypothalamic–pituitary–adrenal (HPA) axis to increase serum glucocorticoid concentrations. Downstream effects of these neuroendocrine signals may include decreased total body weights or body weight gain; food consumption and activity; altered organ weights (e.g., thymus, spleen, adrenal); lymphocyte depletion in thymus and spleen; altered circulating leukocyte counts (e.g., increased neutrophils with decreased lymphocytes and eosinophils); and altered reproductive functions. Typically, only some of these findings occur in a given study. Stress responses should be interpreted as secondary (indirect) rather than primary (direct) test article–related findings. Determining whether effects are the result of stress requires a weight-of-evidence approach. The evaluation and interpretation of routinely collected data (standard in-life, clinical pathology, and anatomic pathology endpoints) are appropriate and generally sufficient to assess whether or not changes are secondary to stress. The impact of possible stress-induced effects on data interpretation can partially be mitigated by toxicity study designs that use appropriate control groups (e.g., cohorts treated with vehicle and subjected to the same procedures as those dosed with test article), housing that minimizes isolation and offers environmental enrichment, and experimental procedures that minimize stress and sampling and analytical bias. This article is a comprehensive overview of the biological aspects of the stress response, beginning with a Summary (Section 1) and an Introduction (Section 2) that describes the historical and conventional methods used to characterize acute and chronic stress responses. These sections are followed by reviews of the primary systems and parameters that regulate and/or are influenced by stress, with an emphasis on parameters evaluated in toxicity studies: In-life Procedures (Section 3), Nervous System (Section 4), Endocrine System (Section 5), Reproductive System (Section 6), Clinical Pathology (Section 7), and Immune System (Section 8). The paper concludes (Section 9) with a brief discussion on Minimizing Stress-Related Effects (9.1.), and a final section explaining why Parameters routinely measured are appropriate for assessing the role of stress in toxicology studies (9.2.).
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Affiliation(s)
| | | | - Keith L. Bailey
- Oklahoma Animal Disease Diagnostic Laboratory, Oklahoma State University, Stillwater, Oklahoma, USA
| | - Brad Bolon
- Department of Veterinary Biosciences and the Comparative Pathology and Mouse Phenotyping Shared Resource, The Ohio State University, Columbus, Ohio, USA
| | | | | | - Thomas J. Rosol
- Department of Veterinary Biosciences, The Ohio State University, Columbus, Ohio, USA
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9
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Roth LW, Polotsky AJ. Can we live longer by eating less? A review of caloric restriction and longevity. Maturitas 2012; 71:315-9. [PMID: 22281163 DOI: 10.1016/j.maturitas.2011.12.017] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2011] [Accepted: 12/23/2011] [Indexed: 10/14/2022]
Abstract
Caloric restriction, decreasing caloric intake by 20-30%, was first shown to extend life in rats nearly 80 years ago. Since that time, limiting food intake for longevity has been investigated in species from yeast to humans. In yeast and lower animals, caloric restriction has repeatedly been demonstrated to lengthen the life span. Studies of caloric restriction in non-human primates and in humans are ongoing and initial results suggest prolongation of life as well as prevention of age-related disease. There is also data in rodents suggesting that short term caloric restriction has beneficial effects on fertility. Although caloric restriction has many positive effects on health and longevity, quality of life on a restricted diet as well as the ability to maintain that diet long term are concerns that must be considered in humans.
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Affiliation(s)
- Lauren W Roth
- University of Colorado, Denver, Department of Obstetrics and Gynecology, Section of Reproductive Endocrinology and Infertility, 12631 East 17th Avenue, B-189-3 Aurora, CO 80045, USA.
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10
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Meeting Report: American Aging Association 40th Annual Meeting, Raleigh, North Carolina, June 3–6, 2011. Rejuvenation Res 2011; 14:449-55. [DOI: 10.1089/rej.2011.1216] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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11
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Abstract
In the 75 years since the seminal observation of Clive McCay that restriction of calorie intake extends the lifespan of rats, a great deal has been learned about the effects of calorie restriction (CR; reduced intake of a nutritious diet) on aging in various short-lived animal models. Studies have demonstrated many beneficial effects of CR on health, the rate of aging, and longevity. Two prospective investigations of the effects of CR on long-lived nonhuman primate (NHP) species began nearly 25 years ago and are still under way. This review presents the design, methods, and main findings of these and other important contributing studies, which have generally revealed beneficial effects of CR on physiological function and the retardation of disease consistent with studies in other species. Specifically, prolonged CR appears to extend the lifespan of rhesus monkeys, which exhibited lower body fat; slower rate of muscle loss with age; lower incidence of neoplasia, cardiovascular disease, type 2 diabetes mellitus, and endometriosis; improved insulin sensitivity and glucose tolerance; and no apparent adverse effect on bone health, as well as a reduction in total energy expenditure. In addition, there are no reports of deleterious effects of CR on reproductive endpoints, and brain morphology is preserved by CR. Adrenal and thyroid hormone profiles are inconsistently affected. More research is needed to delineate the mechanisms of the desirable outcomes of CR and to develop interventions that can produce similar beneficial outcomes for humans. This research offers tremendous potential for producing novel insights into aging and risk of disease.
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Affiliation(s)
- Joseph W Kemnitz
- Wisconsin National Primate Research Center, 1220 Capitol Court, Madison, WI 53715-1299, USA.
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12
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Ottinger MA. Mechanisms of reproductive aging: conserved mechanisms and environmental factors. Ann N Y Acad Sci 2010; 1204:73-81. [PMID: 20738277 DOI: 10.1111/j.1749-6632.2010.05653.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The interplay of neuroendocrine processes and gonadal function is exquisitely expressed during aging. In females, loss of ovarian function results in decreased circulating estradiol. As a result, estrogen-dependent endocrine and behavioral responses decline, including impaired cognitive function reflecting the impact of declining estrogen on the hippocampus circuits, and decreased metabolic endocrine function. Concurrently, age-related changes in neuroendocrine response also contribute to the declining reproductive function. Our session considered key mechanisms in reproductive aging including the roles of ovarian function (Finch and Holmes) and the hypothalamic median eminence (Yin and Gore) with an associated age-related cognitive decline that accompanies estrogen loss (Morrison and colleagues). Effects of smoking, obesity, and insulin resistance (Sowers and colleagues) impact the timing of the perimenopause transition in women. Animal models provide excellent insights into conserved mechanisms and key overarching events that bring about endocrine and behavioral aging. Environmental factors are key triggers in timing endocrine aging with implications for eventual disease. Session presentations will be considered in the context of the broader topic of indices and predictors of aging-related change.
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Affiliation(s)
- Mary Ann Ottinger
- Department of Animal and Avian Sciences, University of Maryland, College Park, Maryland 20742, USA.
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13
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Sitzmann BD, Leone EH, Mattison JA, Ingram DK, Roth GS, Urbanski HF, Zelinski MB, Ottinger MA. Effects of moderate calorie restriction on testosterone production and semen characteristics in young rhesus macaques (Macaca mulatta). Biol Reprod 2010; 83:635-40. [PMID: 20610809 DOI: 10.1095/biolreprod.110.084186] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
We have previously reported a modest influence of moderate calorie restriction (CR) on testicular gene expression in young adult rhesus macaques (Macaca mulatta); however, it is unclear if these modifications correspond to subsequent changes in testicular function or sperm physiology. This study extends our earlier findings to examine potential physiological differences due to this differential gene expression. Animals were subjected to 30% CR (CR, n = 5) or were fed a standard control diet (CON, n = 5) starting during their peripubertal period. Circulating testosterone (T) levels were measured across a 24-h period after 7 yr of dietary treatment and were found to be similar in CR and CON males; however, maintenance of daily minimum T levels was significantly higher in the CR animals. Semen collection was performed on the same cohort of animals three times per male (CR, n = 4; CON, n = 4) after 8 yr of treatment, and samples were assessed by a variety of measures. Parameters, including semen quality and sperm cell viability and function, showed less variability in semen samples taken from CR males, but overall testicular function and sperm quality were comparable regardless of diet. There is mounting evidence that CR may promote health and longevity in a wide range of organisms, including nonhuman primates. Importantly, our data suggest that moderate CR has no obvious lasting detrimental effect on testicular function and sperm parameters in young adult primates and may in fact help maintain higher levels of circulating T.
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Affiliation(s)
- Brandon D Sitzmann
- Department of Animal and Avian Sciences, University of Maryland, College Park, Maryland, USA
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