1
|
Rolon S, Huynh C, Guenther M, Gardezi M, Phillips J, Gehrand AL, Raff H. Insulin and glucose responses to hypoxia in male and female neonatal rats: Effects of the androgen receptor antagonist flutamide. Physiol Rep 2021; 9:e14663. [PMID: 33393733 PMCID: PMC7780235 DOI: 10.14814/phy2.14663] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 11/02/2020] [Accepted: 11/03/2020] [Indexed: 01/12/2023] Open
Abstract
Hypoxia is common with preterm birth and may lead to long-term effects on adult pancreatic endocrine function and insulin sensitivity. This phenomenon may be sexually dimorphic due to the hypoxia-induced augmentation of the neonatal androgen surge in male newborns. We evaluated this phenomenon by pretreating neonatal rats on postnatal days (PD) 1, 6, 13, or 20 with flutamide (a nonsteroidal androgen receptor antagonist) at a standard or a high dose (10 or 50 mg/kg) compared to vehicle control. One day later, neonatal rats were exposed to either acute normoxic or hypoxic separation (fasting) for 90 min, and blood was sampled for the measurement of insulin and glucose and the calculation of HOMA-IR as an index of insulin resistance. During normoxic and hypoxic separation (fasting), flutamide increased insulin secretion in PD2, PD7, and PD14 pups, high dose flutamide attenuated insulin secretion, and high dose flutamide attenuated the increase in HOMA-IR due to hypoxia. Our studies suggest a unique role of the androgen receptor in the control of neonatal pancreatic function, possibly by blocking a direct effect of neonatal testosterone or in response to indirect regulatory effects of androgens on insulin sensitivity.
Collapse
Affiliation(s)
- Santiago Rolon
- Endocrine Research LaboratoryAurora St. Luke's Medical CenterAdvocate Aurora Research InstituteMilwaukeeWIUSA
- Department of MedicineMedical College of WisconsinMilwaukeeWIUSA
| | - Christine Huynh
- Endocrine Research LaboratoryAurora St. Luke's Medical CenterAdvocate Aurora Research InstituteMilwaukeeWIUSA
| | - Maya Guenther
- Endocrine Research LaboratoryAurora St. Luke's Medical CenterAdvocate Aurora Research InstituteMilwaukeeWIUSA
| | - Minhal Gardezi
- Endocrine Research LaboratoryAurora St. Luke's Medical CenterAdvocate Aurora Research InstituteMilwaukeeWIUSA
| | - Jonathan Phillips
- Endocrine Research LaboratoryAurora St. Luke's Medical CenterAdvocate Aurora Research InstituteMilwaukeeWIUSA
| | - Ashley L. Gehrand
- Endocrine Research LaboratoryAurora St. Luke's Medical CenterAdvocate Aurora Research InstituteMilwaukeeWIUSA
| | - Hershel Raff
- Endocrine Research LaboratoryAurora St. Luke's Medical CenterAdvocate Aurora Research InstituteMilwaukeeWIUSA
- Department of MedicineMedical College of WisconsinMilwaukeeWIUSA
- Department of SurgeryMedical College of WisconsinMilwaukeeWIUSA
- Department of PhysiologyMedical College of WisconsinMilwaukeeWIUSA
| |
Collapse
|
2
|
Zuloaga DG, Heck AL, De Guzman RM, Handa RJ. Roles for androgens in mediating the sex differences of neuroendocrine and behavioral stress responses. Biol Sex Differ 2020; 11:44. [PMID: 32727567 PMCID: PMC7388454 DOI: 10.1186/s13293-020-00319-2] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Accepted: 07/09/2020] [Indexed: 12/17/2022] Open
Abstract
Estradiol and testosterone are powerful steroid hormones that impact brain function in numerous ways. During development, these hormones can act to program the adult brain in a male or female direction. During adulthood, gonadal steroid hormones can activate or inhibit brain regions to modulate adult functions. Sex differences in behavioral and neuroendocrine (i.e., hypothalamic pituitary adrenal (HPA) axis) responses to stress arise as a result of these organizational and activational actions. The sex differences that are present in the HPA and behavioral responses to stress are particularly important considering their role in maintaining homeostasis. Furthermore, dysregulation of these systems can underlie the sex biases in risk for complex, stress-related diseases that are found in humans. Although many studies have explored the role of estrogen and estrogen receptors in mediating sex differences in stress-related behaviors and HPA function, much less consideration has been given to the role of androgens. While circulating androgens can act by binding and activating androgen receptors, they can also act by metabolism to estrogenic molecules to impact estrogen signaling in the brain and periphery. This review focuses on androgens as an important hormone for modulating the HPA axis and behaviors throughout life and for setting up sex differences in key stress regulatory systems that could impact risk for disease in adulthood. In particular, impacts of androgens on neuropeptide systems known to play key roles in HPA and behavioral responses to stress (corticotropin-releasing factor, vasopressin, and oxytocin) are discussed. A greater knowledge of androgen action in the brain is key to understanding the neurobiology of stress in both sexes.
Collapse
Affiliation(s)
| | - Ashley L Heck
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, USA
| | | | - Robert J Handa
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, USA.
| |
Collapse
|
3
|
Rolon S, Huynh C, Guenther M, Gardezi M, Phillips J, Gehrand AL, Raff H. The effects of flutamide on the neonatal rat hypothalamic-pituitary-adrenal and gonadal axes in response to hypoxia. Physiol Rep 2019; 7:e14318. [PMID: 31876126 PMCID: PMC6930936 DOI: 10.14814/phy2.14318] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Hypoxia is common with preterm birth and may lead to long-term effects on the adult hypothalamic-pituitary-adrenal (HPA) axis that are sexually dimorphic due to neonatal androgens. Although the adult rat adrenal does not express appreciable CYP17 activity, the neonatal rat adrenal may synthesize androgens that could be a critical local factor in the development of adrenal function. We evaluated these phenomena by pretreating the neonatal rats on postnatal days (PD) 1, 6, 13, 20 with flutamide (a nonsteroidal androgen receptor antagonist) at a standard or a high dose (10 mg/kg or 50 mg/kg) compared to vehicle control. One day later, neonatal rats were exposed to acute hypoxia and blood was sampled. We found that (a) in PD2 pups, flutamide augmented corticosterone responses in a sexually dimorphic pattern and without an increase in ACTH, (b) PD7 and PD14 pups had the smallest corticosterone response to hypoxia (c) PD21 pups had an adult-like corticosterone response to hypoxia that was sexually dimorphic, (d) flutamide attenuated ACTH responses in PD7 hypoxic pups, and (e) high-dose flutamide suppressed the HPA axis, FSH, and estradiol. Flutamide demonstrated mixed antagonist and agonist effects that changed during the first three weeks of neonatal life. We conclude that the use of flutamide in neonatal rats to evaluate androgen-induced programming of subsequent adult behavior is not optimal. However, our studies suggest neonatal androgens play a role in regulation of adrenal function that is sexually dimorphic and changes during early development.
Collapse
Affiliation(s)
- Santiago Rolon
- Endocrine Research LaboratoryAurora St. Luke’s Medical CenterAurora Research InstituteMilwaukeeWisconsin
- Department of MedicineMedical College of WisconsinMilwaukeeWisconsin
| | - Christine Huynh
- Endocrine Research LaboratoryAurora St. Luke’s Medical CenterAurora Research InstituteMilwaukeeWisconsin
| | - Maya Guenther
- Endocrine Research LaboratoryAurora St. Luke’s Medical CenterAurora Research InstituteMilwaukeeWisconsin
| | - Minhal Gardezi
- Endocrine Research LaboratoryAurora St. Luke’s Medical CenterAurora Research InstituteMilwaukeeWisconsin
| | - Jonathan Phillips
- Endocrine Research LaboratoryAurora St. Luke’s Medical CenterAurora Research InstituteMilwaukeeWisconsin
| | - Ashley L. Gehrand
- Endocrine Research LaboratoryAurora St. Luke’s Medical CenterAurora Research InstituteMilwaukeeWisconsin
| | - Hershel Raff
- Endocrine Research LaboratoryAurora St. Luke’s Medical CenterAurora Research InstituteMilwaukeeWisconsin
- Department of MedicineMedical College of WisconsinMilwaukeeWisconsin
- Department of SurgeryMedical College of WisconsinMilwaukeeWisconsin
- Department of PhysiologyMedical College of WisconsinMilwaukeeWisconsin
| |
Collapse
|
4
|
Green MR, Zeidan M, Hodges TE, McCormick CM. Age-dependent regulation by androgens of gene expression in the anterior hypothalamus and stress-induced release of adrenal hormones in adolescent and adult male rats. J Neuroendocrinol 2019; 31:e12714. [PMID: 30912177 DOI: 10.1111/jne.12714] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 02/06/2019] [Accepted: 03/21/2019] [Indexed: 01/05/2023]
Abstract
Adolescents show greater and/or more prolonged activation of the hypothalamic-pituitary-adrenal axis in response to stressors than adults, although the basis for such an age difference is not understood. We investigated developmental shifts in the regulation of HPA function by testosterone using androgen replacement in orchiectomised (OCX) pre-pubertal and post-pubertal adolescent rats and in adults, as well as using inhibitors of testosterone synthesis in non-operated rats. The expected dampening effect of testosterone in adult OCX rats did not meet statistical significance in all of the three experiments. Nevertheless, in each, adolescents had higher post-stress concentrations of corticosterone compared to adults despite similar concentrations of testosterone. The effect of testosterone was in the opposite direction in post-pubertal adolescents compared to that in adults, with testosterone replacement leading to increased rather than lower corticosterone concentration. Testosterone replacement decreased arginine vasopressin and corticotrophin-releasing hormone immune-reactive cell counts in the paraventricular nucleus at all ages. In a fourth experiment, we provide evidence that the basis of the age difference in corticosterone release is because of a greater conversion of testosterone to oestradiol in adolescents and a greater conversion of testosterone to dihydrotestosterone in adults: aromatase inhibition had little effect in adults and attenuated the age difference by decreasing stress-induced corticosterone release in adolescents. By contrast, 5α-reductase inhibition or an androgen receptor antagonist had little effect in adolescents and attenuated the age difference by increasing stress-induced corticosterone release in adults. In the adrenal gland, adolescents had reduced 5α-reductase and androgen receptor gene expression. There also were age differences in the regulation of hypothalamic mRNA expression of androgen receptors, oestrogen receptors and aromatase by testosterone. In sum, the results suggest that developmental shifts in the synthesis of testosterone and the regulation of gene expression are factors with respect to age differences in corticosterone release in response to stressors.
Collapse
Affiliation(s)
- Matthew R Green
- Department of Anatomy and Cell Biology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada
- Department of Psychology, Brock University, St. Catharines, Ontario, Canada
| | - Mostafa Zeidan
- Department of Biological Sciences, Brock University, St Catharines, Ontario, Canada
| | - Travis E Hodges
- Department of Psychology, Brock University, St. Catharines, Ontario, Canada
| | - Cheryl M McCormick
- Department of Psychology, Brock University, St. Catharines, Ontario, Canada
- Department of Biological Sciences, Brock University, St Catharines, Ontario, Canada
| |
Collapse
|
5
|
Heck AL, Handa RJ. Sex differences in the hypothalamic-pituitary-adrenal axis' response to stress: an important role for gonadal hormones. Neuropsychopharmacology 2019; 44:45-58. [PMID: 30111811 PMCID: PMC6235871 DOI: 10.1038/s41386-018-0167-9] [Citation(s) in RCA: 245] [Impact Index Per Article: 49.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Revised: 07/19/2018] [Accepted: 07/22/2018] [Indexed: 12/11/2022]
Abstract
The hypothalamic-pituitary-adrenal (HPA) axis, a neuroendocrine network that controls hormonal responses to internal and external challenges in an organism's environment, exhibits strikingly sex-biased activity. In adult female rodents, acute HPA function following a stressor is markedly greater than it is in males, and this difference has largely been attributed to modulation by the gonadal hormones testosterone and estradiol. These gonadal hormones are produced by the hypothalamic-pituitary-gonadal (HPG) axis and have been shown to determine sex differences in adult HPA function after acute stress via their activational and organizational effects. Although these actions of gonadal hormones are well supported, the possibility that sex chromosomes similarly influence HPA activity is unexplored. Moreover, questions remain regarding sex differences in the activity of the HPA axis following chronic stress and the underlying contributions of gonadal hormones and sex chromosomes. The present review examines what is currently known about sex differences in the neuroendocrine response to stress, as well as outstanding questions regarding this sex bias. Although it primarily focuses on the rodent literature, a brief discussion of sex differences in the human HPA axis is also included.
Collapse
Affiliation(s)
- Ashley L. Heck
- 0000 0004 1936 8083grid.47894.36Department of Biomedical Sciences, Colorado State University, Fort Collins, CO 80523 USA
| | - Robert J. Handa
- 0000 0004 1936 8083grid.47894.36Department of Biomedical Sciences, Colorado State University, Fort Collins, CO 80523 USA
| |
Collapse
|
6
|
Schroeder A, van den Buuse M, Hill RA. Reelin Haploinsufficiency and Late-Adolescent Corticosterone Treatment Induce Long-Lasting and Female-Specific Molecular Changes in the Dorsal Hippocampus. Brain Sci 2018; 8:brainsci8070118. [PMID: 29941797 PMCID: PMC6070826 DOI: 10.3390/brainsci8070118] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Revised: 06/20/2018] [Accepted: 06/22/2018] [Indexed: 12/24/2022] Open
Abstract
Reelin depletion and stress seem to affect similar pathways including GABAergic and glutamatergic signaling and both are implicated in psychiatric disorders in late adolescence/early adulthood. The interaction between reelin depletion and stress, however, remains unclear. To investigate this, male and female heterozygous reelin mice (HRM) and wildtype (WT) controls were treated with the stress hormone, corticosterone (CORT), during late adolescence to simulate chronic stress. Glucocorticoid receptors (GR), N-methyl-d-aspartate receptor (NMDAr) subunits, glutamic acid decarboxylase (GAD67) and parvalbumin (PV) were measured in the hippocampus and the prefrontal cortex (PFC) in adulthood. While no changes were seen in male mice, female HRM showed a significant reduction in GR expression in the dorsal hippocampus. In addition, CORT reduced GR levels as well as GluN2B and GluN2C subunits of NMDAr in the dorsal hippocampus in female mice only. CORT furthermore reduced GluN1 levels in the PFC of female mice. The combined effect of HRM and CORT treatment appeared to be additive in terms of GR expression in the dorsal hippocampus. Female-specific CORT-induced changes were associated with overall higher circulating CORT levels in female compared to male mice. This study shows differential effects of reelin depletion and CORT treatment on GR and NMDAr protein expression in male and female mice, suggesting that females are more susceptible to reelin haploinsufficiency as well as late-adolescent stress. These findings shed more light on female-specific vulnerability to stress and have implications for stress-associated mental illnesses with a female bias including anxiety and major depression.
Collapse
Affiliation(s)
- Anna Schroeder
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville 3052, Australia.
- Department of Psychiatry, School of Clinical Sciences, Monash University, Clayton 3168, Australia.
| | - Maarten van den Buuse
- School of Psychology and Public Health, La Trobe University, Bundoora 3086 Australia.
- Department of Pharmacology, University of Melbourne, Parkville 3052, Australia.
- The College of Public Health, Medical and Veterinary Sciences, James Cook University, Townsville 4810, Australia.
| | - Rachel A Hill
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville 3052, Australia.
- Department of Psychiatry, School of Clinical Sciences, Monash University, Clayton 3168, Australia.
| |
Collapse
|
7
|
Domonkos E, Borbélyová V, Kolátorová L, Chlupáčová T, Ostatníková D, Hodosy J, Stárka L, Celec P. Sex differences in the effect of prenatal testosterone exposure on steroid hormone production in adult rats. Physiol Res 2018; 66:S367-S374. [PMID: 28948821 DOI: 10.33549/physiolres.933722] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Maternal hyperandrogenism during pregnancy might have metabolic and endocrine consequences on the offspring as shown for the polycystic ovary syndrome. Despite numerous experiments, the impact of prenatal hyperandrogenic environment on postnatal sex steroid milieu is not yet clear. In this study, we investigated the effect of prenatal testosterone excess on postnatal concentrations of luteinizing hormone, corticosterone and steroid hormones including testosterone, pregnenolone, progesterone, estradiol and 7beta-hydroxy-epiandrosterone in the offspring of both sexes. Pregnant rats were injected daily with either testosterone propionate or vehicle from gestational day 14 until parturition. The hormones were evaluated in plasma of the adult offspring. As expected, females had lower testosterone and higher pregnenolone, progesterone and estradiol in comparison to males. In addition, corticosterone was higher in females than in males, and it was further elevated by prenatal testosterone treatment. In males, prenatal testosterone exposure resulted in higher 7beta-hydroxy-epiandrosterone in comparison to control group. None of the other analyzed hormones were affected by prenatal testosterone. In conclusion, our results did not show major effects on sex hormone production or luteinizing hormone release in adult rats resulting from testosterone excess during their fetal development. However, maternal hyperandrogenism seems to partially affect steroid biosynthesis in sex-specific manner.
Collapse
Affiliation(s)
- E Domonkos
- Institute of Molecular Biomedicine, Faculty of Medicine, Comenius University, Bratislava, Slovakia.
| | | | | | | | | | | | | | | |
Collapse
|
8
|
Green MR, McCormick CM. Sex and stress steroids in adolescence: Gonadal regulation of the hypothalamic-pituitary-adrenal axis in the rat. Gen Comp Endocrinol 2016; 234:110-6. [PMID: 26851306 DOI: 10.1016/j.ygcen.2016.02.004] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Accepted: 02/02/2016] [Indexed: 01/19/2023]
Abstract
This review provides an overview of the current understanding of the role of the hypothalamic-pituitary-gonadal (HPG) axis in regulating the hypothalamic-pituitary-adrenal (HPA) axis response to stressors. HPA function is influenced by both organizational (programming) and activational effects of gonadal hormones. Typically, in adult rats, estradiol increases and androgens decrease the HPA response to stressors, thereby contributing to sex differences in HPA function, and sensitivity of the HPA axis to gonadal steroids is in part determined by exposure to these hormones in early development. Although developmental differences in HPA function are well characterized, the extent to which gonadal steroids contribute to age differences in HPA function is not well understood. Deficits in the understanding of the relationships between the HPA and HPG axes are greatest for the adolescent period of development. The critical outstanding questions are, when do gonadal hormones begin to regulate HPA function in adolescence, and what mechanisms precipitate change in sensitivity of the HPA axis to the HPG axis at this stage of life.
Collapse
Affiliation(s)
- Matthew R Green
- Department of Psychology, Brock University, 500 Glenridge Avenue, St. Catharines, Ontario L2S 3A1, Canada
| | - Cheryl M McCormick
- Department of Psychology, Brock University, 500 Glenridge Avenue, St. Catharines, Ontario L2S 3A1, Canada; Centre for Neuroscience, Brock University, 500 Glenridge Avenue, St. Catharines, Ontario L2S 3A1, Canada.
| |
Collapse
|
9
|
Oti T, Takanami K, Katayama N, Edey T, Satoh K, Sakamoto T, Sakamoto H. Perinatal testosterone exposure is critical for the development of the male-specific sexually dimorphic gastrin-releasing peptide system in the lumbosacral spinal cord that mediates erection and ejaculation. Biol Sex Differ 2016; 7:4. [PMID: 26759714 PMCID: PMC4710030 DOI: 10.1186/s13293-016-0058-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Accepted: 01/04/2016] [Indexed: 02/02/2023] Open
Abstract
Background In rats, a sexually dimorphic spinal gastrin-releasing peptide (GRP) system in the lumbosacral spinal cord projects to spinal centers that control erection and ejaculation. This system controls the sexual function of adult males in an androgen-dependent manner. In the present study, we assessed the influence of androgen exposure on the spinal GRP system during a critical period of the development of sexual dimorphism. Methods Immunohistochemistry was used to determine if the development of the spinal GRP system is regulated by the perinatal androgen surge. We first analyzed the responses of neonates administered with anti-androgen flutamide. To remove endogenous androgens, rats were castrated at birth. Further, neonatal females were administered androgens during a critical period to evaluate the development of the male-specific spinal GRP system. Results Treatment of neonates with flutamide on postnatal days 0 and 1 attenuated the spinal GRP system during adulthood. Castrating male rats at birth resulted in a decrease in the number of GRP neurons and the intensity of neuronal GRP in the spinal cord during adulthood despite testosterone supplementation during puberty. This effect was prevented if the rats were treated with testosterone propionate immediately after castration. Moreover, treating female rats with androgens on the day of birth and the next day, masculinized the spinal GRP system during adulthood, which resembled the masculinized phenotype of adult males and induced a hypermasculine appearance. Conclusions The perinatal androgen surge plays a key role in masculinization of the spinal GRP system that controls male sexual behavior. Further, the present study provides potentially new approaches to treat sexual disorders of males.
Collapse
Affiliation(s)
- Takumi Oti
- Ushimado Marine Institute (UMI), Graduate School of Natural Science and Technology, Okayama University, 130-17 Kashino, Ushimado, Setouchi, Okayama 701-4303 Japan
| | - Keiko Takanami
- Ushimado Marine Institute (UMI), Graduate School of Natural Science and Technology, Okayama University, 130-17 Kashino, Ushimado, Setouchi, Okayama 701-4303 Japan
| | - Nao Katayama
- Ushimado Marine Institute (UMI), Graduate School of Natural Science and Technology, Okayama University, 130-17 Kashino, Ushimado, Setouchi, Okayama 701-4303 Japan
| | - Tomoca Edey
- Ushimado Marine Institute (UMI), Graduate School of Natural Science and Technology, Okayama University, 130-17 Kashino, Ushimado, Setouchi, Okayama 701-4303 Japan
| | - Keita Satoh
- Ushimado Marine Institute (UMI), Graduate School of Natural Science and Technology, Okayama University, 130-17 Kashino, Ushimado, Setouchi, Okayama 701-4303 Japan
| | - Tatsuya Sakamoto
- Ushimado Marine Institute (UMI), Graduate School of Natural Science and Technology, Okayama University, 130-17 Kashino, Ushimado, Setouchi, Okayama 701-4303 Japan
| | - Hirotaka Sakamoto
- Ushimado Marine Institute (UMI), Graduate School of Natural Science and Technology, Okayama University, 130-17 Kashino, Ushimado, Setouchi, Okayama 701-4303 Japan
| |
Collapse
|
10
|
Goel N, Workman JL, Lee TT, Innala L, Viau V. Sex differences in the HPA axis. Compr Physiol 2015; 4:1121-55. [PMID: 24944032 DOI: 10.1002/cphy.c130054] [Citation(s) in RCA: 245] [Impact Index Per Article: 27.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The hypothalamic-pituitary-adrenal (HPA) axis is a major component of the systems that respond to stress, by coordinating the neuroendocrine and autonomic responses. Tightly controlled regulation of HPA responses is critical for maintaining mental and physical health, as hyper- and hypo-activity have been linked to disease states. A long history of research has revealed sex differences in numerous components of the HPA stress system and its responses, which may partially form the basis for sex disparities in disease development. Despite this, many studies use male subjects exclusively, while fewer reports involve females or provide direct sex comparisons. The purpose of this article is to present sex comparisons in the functional and molecular aspects of the HPA axis, through various phases of activity, including basal, acute stress, and chronic stress conditions. The HPA axis in females initiates more rapidly and produces a greater output of stress hormones. This review focuses on the interactions between the gonadal hormone system and the HPA axis as the key mediators of these sex differences, whereby androgens increase and estrogens decrease HPA activity in adulthood. In addition to the effects of gonadal hormones on the adult response, morphological impacts of hormone exposure during development are also involved in mediating sex differences. Additional systems impinging on the HPA axis that contribute to sex differences include the monoamine neurotransmitters norepinephrine and serotonin. Diverse signals originating from the brain and periphery are integrated to determine the level of HPA axis activity, and these signals are, in many cases, sex-specific.
Collapse
Affiliation(s)
- Nirupa Goel
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | | | | | | | | |
Collapse
|
11
|
Panagiotakopoulos L, Neigh GN. Development of the HPA axis: where and when do sex differences manifest? Front Neuroendocrinol 2014; 35:285-302. [PMID: 24631756 DOI: 10.1016/j.yfrne.2014.03.002] [Citation(s) in RCA: 94] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Revised: 02/22/2014] [Accepted: 03/04/2014] [Indexed: 01/21/2023]
Abstract
Sex differences in the response to stress contribute to sex differences in somatic, neurological, and psychiatric diseases. Despite a growing literature on the mechanisms that mediate sex differences in the stress response, the ontogeny of these differences has not been comprehensively reviewed. This review focuses on the development of the hypothalamic-pituitary-adrenal (HPA) axis, a key component of the body's response to stress, and examines the critical points of divergence during development between males and females. Insight gained from animal models and clinical studies are presented to fully illustrate the current state of knowledge regarding sex differences in response to stress over development. An appreciation for the developmental timelines of the components of the HPA axis will provide a foundation for future areas of study by highlighting both what is known and calling attention to areas in which sex differences in the development of the HPA axis have been understudied.
Collapse
Affiliation(s)
| | - Gretchen N Neigh
- Emory University, Department of Physiology, United States; Emory University, Department of Psychiatry & Behavioral Sciences, United States.
| |
Collapse
|
12
|
Effects of social context on endocrine function and Zif268 expression in response to an acute stressor in adolescent and adult rats. Int J Dev Neurosci 2014; 35:25-34. [PMID: 24613747 DOI: 10.1016/j.ijdevneu.2014.03.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Revised: 02/04/2014] [Accepted: 03/01/2014] [Indexed: 01/09/2023] Open
Abstract
There is a paucity of studies comparing social buffering in adolescents and adults, despite their marked differences in social behavior. We investigated whether greater effects of social buffering on plasma corticosterone concentrations and expression of Zif268 in neural regions after an acute stressor would be found in adolescent than adult rats. Samples were obtained before and after 1h of isolation stress and after either 1 or 3h of recovery back in the colony with either a familiar or unfamiliar cage partner. Adolescent and adult rats did not differ in plasma concentrations of corticosterone at any time point. Corticosterone concentrations were higher after 1h isolation than at baseline (p<0.001), and rats with a familiar partner during the recovery phase had lower corticosterone concentrations than did rats with an unfamiliar partner (p=0.02). Zif268 immunoreactive cell counts were higher in the arcuate nucleus in both age groups after isolation (p=0.007) and in the paraventricular nucleus of adolescents than adults during the recovery phase irrespective of partner familiarity. There was a significant decrease in immunoreactive cell counts after 1h isolation compared to baseline in the basolateral amygdala, central nucleus of the amygdala, and in the pyramidal layer of the hippocampus (all p<0.05). An effect of partner familiarity on Zif268 immunoreactive cell counts was found in the granule layer of the dentate gyrus irrespective of age (higher in those with a familiar partner, p=0.03) and in the medial prefrontal cortex in adolescents (higher with an unfamiliar partner, p=0.02). Overall, the acute stress and partner familiarity produced a similar pattern of results in adolescents and adults, with both age groups sensitive to the social context.
Collapse
|
13
|
Brown GR, Spencer KA. Steroid hormones, stress and the adolescent brain: a comparative perspective. Neuroscience 2012; 249:115-28. [PMID: 23262238 DOI: 10.1016/j.neuroscience.2012.12.016] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2012] [Revised: 11/30/2012] [Accepted: 12/01/2012] [Indexed: 02/07/2023]
Abstract
Steroid hormones, including those produced by the gonads and the adrenal glands, are known to influence brain development during sensitive periods of life. Until recently, most brain organisation was assumed to take place during early stages of development, with relatively little neurogenesis or brain re-organisation during later stages. However, an increasing body of research has shown that the developing brain is also sensitive to steroid hormone exposure during adolescence (broadly defined as the period from nutritional independence to sexual maturity). In this review, we examine how steroid hormones that are produced by the gonads and adrenal glands vary across the lifespan in a range of mammalian and bird species, and we summarise the evidence that steroid hormone exposure influences behavioural and brain development during early stages of life and during adolescence in these two taxonomic groups. Taking a cross-species, comparative perspective reveals that the effects of early exposure to steroid hormones depend upon the stage of development at birth or hatching, as measured along the altricial-precocial dimension. We then review the evidence that exposure to stress during adolescence impacts upon the developing neuroendocrine systems, the brain and behaviour. Current research suggests that the effects of adolescent stress vary depending upon the sex of the individual and type of stressor, and the effects of stress could involve several neural systems, including the serotonergic and dopaminergic systems. Experience of stressors during adolescence could also influence brain development via the close interactions between the stress hormone and gonadal hormone axes. While sensitivity of the brain to steroid hormones during early life and adolescence potentially leaves the developing organism vulnerable to external adversities, developmental plasticity also provides an opportunity for the developing organism to respond to current circumstances and for behavioural responses to influence the future life history of the individual.
Collapse
Affiliation(s)
- G R Brown
- School of Psychology and Neuroscience, University of St Andrews, UK.
| | | |
Collapse
|
14
|
Hofmann PJ, Michaelis M, Gotz F, Bartel C, Kienitz T, Quinkler M. Flutamide increases aldosterone levels in gonadectomized male but not female Wistar rats. Am J Hypertens 2012; 25:697-703. [PMID: 22402471 DOI: 10.1038/ajh.2012.21] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND Sex-specific differences in blood pressure (BP) suggest an important modulating role of testosterone in the kidney. However, little is known about the interaction between androgens and the mineralocorticoid aldosterone. Our objective was to determine the effects of testosterone in gonadectomized male and female rats on a low-salt diet, and to determine the effect of androgen receptor (AR) blockade by flutamide on BP and on aldosterone levels. METHODS Normotensive male and female Wistar rats were gonadectomized and put on a low-salt diet. They were treated for 16 days with testosterone or placebo. In addition, the animals received the AR antagonist flutamide or placebo, respectively. BP was measured by tail-cuff method, 24-h urine samples were collected in metabolic cages and blood was collected for hormonal measurements. RESULTS Testosterone increased BP in males and females, and this effect could be blocked by flutamide. Flutamide treatment itself significantly increased aldosterone levels in male but not in female rats. These elevated aldosterone levels could be lowered by testosterone treatment during AR blockade. Accordingly to aldosterone levels, flutamide increased in males the serum sodium/potassium to urinary sodium/potassium ratio, an in vivo indicator of renal aldosterone action. CONCLUSIONS Testosterone regulates BP in male and female gonadectomized rats via the AR. Flutamide by itself exerts influence over aldosterone in the absence of gonadal steroid replacement suggesting AR involvement in renal sodium handling. These flutamide effects were sex-specific and not seen in female rats.
Collapse
|
15
|
Bingham B, Wang NXR, Innala L, Viau V. Postnatal aromatase blockade increases c-fos mRNA responses to acute restraint stress in adult male rats. Endocrinology 2012; 153:1603-8. [PMID: 22315450 DOI: 10.1210/en.2011-1749] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Recent evidence suggests that the aromatization of testosterone to estrogen is important for the organizing effects of neonatal testosterone on neuroendocrine responses to acute challenges. However, the extent to which neonatal inhibition of aromatase alters the stress-induced activation of neural pathways has not been examined. Here we assessed central patterns of c-fos mRNA induced by 30 min of restraint in 65-d-old adult male rats that were implanted with sc capsules of the aromatase inhibitor 1,4,6-androstatriene-3,17-dione (ATD), introduced within 12 h of birth and removed on d 21 of weaning. Neonatal ATD decreased the expression of arginine vasopressin within extrahypothalamic regions in adults, confirming reduced estrogen exposure during development. As adults, ATD-treated animals showed higher corticosterone responses at 30 min of restraint exposure compared with control animals as well as higher c-fos expression levels in the paraventricular nucleus of the hypothalamus. ATD treatment also increased stress-induced c-fos within several limbic regions of the forebrain, in addition to areas involved in somatosensory processing. Based on these results, we propose that the conversion of testosterone to estrogen during the neonatal period exerts marked, system-wide effects to organize adult neuroendocrine responses to homeostatic threat.
Collapse
Affiliation(s)
- Brenda Bingham
- Department of Cellular and Physiological Sciences, Life Sciences Centre, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, British Columbia V6T 1Z3, Canada
| | | | | | | |
Collapse
|
16
|
Cunningham RL, Lumia AR, McGinnis MY. Androgen receptors, sex behavior, and aggression. Neuroendocrinology 2012; 96:131-40. [PMID: 22414851 PMCID: PMC3474193 DOI: 10.1159/000337663] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2011] [Accepted: 02/28/2012] [Indexed: 11/19/2022]
Abstract
Androgens are intricately involved in reproductive and aggressive behaviors, but the role of the androgen receptor in mediating these behaviors is less defined. Further, activity of the hypothalamic-pituitary-gonadal axis and hypothalamic-pituitary-adrenal axis can influence each other at the level of the androgen receptor. Knowledge of the mechanisms for androgens' effects on behaviors through the androgen receptor will guide future studies in elucidating male reproductive and aggressive behavior repertoires.
Collapse
Affiliation(s)
- Rebecca L Cunningham
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Centre at Fort Worth, Fort Worth, TX 76107, USA.
| | | | | |
Collapse
|
17
|
Lürzel S, Kaiser S, Sachser N. Social interaction decreases stress responsiveness during adolescence. Psychoneuroendocrinology 2011; 36:1370-7. [PMID: 21493009 DOI: 10.1016/j.psyneuen.2011.03.010] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2010] [Revised: 02/24/2011] [Accepted: 03/18/2011] [Indexed: 01/31/2023]
Abstract
Adolescence is the transition from infancy to adulthood and encompasses major changes in the brain, the endocrine systems, and behavior. During late adolescence, male guinea pigs living in mixed-sex colonies exhibit a lower cortisol (C) response to novelty compared with animals in other ages and housing conditions. It was hypothesized that this reduction in stress responsiveness is induced by a high amount of social interactions in the colonies. In a previous study (Lürzel et al., 2010), late adolescent colony-housed males (CM) were compared with similarly aged males that were housed in heterosexual pairs (PM) as well as with males that were also housed in pairs, but regularly received additional social stimulation by allowing them ten times to interact with unfamiliar adult animals of both sexes for 10 min (SM). CM had a significantly lower stress response than PM, with SM being intermediate and not significantly different from either of the other groups. We assumed that the amount of social stimulation in SM was insufficient in order to achieve a significant reduction of stress responsiveness compared with PM. For the present study, we hypothesized that with a higher amount of social stimulation, a significant difference in stress responsiveness between PM and SM becomes apparent during late adolescence. Thus, PM were again compared with SM that, this time, had received twice as much social stimulation as in the previous study. As a result, stress responsiveness was indeed significantly lower in SM than in PM during late adolescence. Thus, a high amount of social interactions during the course of adolescence leads to a decreased stress responsiveness. Furthermore, SM showed an increase in testosterone (T) levels caused by social stimulation. We hypothesize that the reduction in stress responsiveness is brought about by high T levels that organize central neural structures over the course of adolescence.
Collapse
Affiliation(s)
- Stephanie Lürzel
- Department of Behavioural Biology, University of Münster, Badestraße 13, 48149 Münster, Germany.
| | | | | |
Collapse
|
18
|
Postnatal blockade of androgen receptors or aromatase impair the expression of stress hypothalamic-pituitary-adrenal axis habituation in adult male rats. Psychoneuroendocrinology 2011; 36:249-57. [PMID: 20719434 DOI: 10.1016/j.psyneuen.2010.07.015] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2010] [Revised: 07/06/2010] [Accepted: 07/19/2010] [Indexed: 11/20/2022]
Abstract
Sex steroid hormones during development permanently alter, or organize, the brain and behavior, while during adulthood they act to reversibly modulate, or activate, physiology and behavior. Testosterone exerts both organizational and activational effects on the magnitude of the hypothalamic-pituitary-adrenal (HPA) axis response to acute stress. What has never been approached is how testosterone can organize habituation of the HPA axis, in which stress induced elevations in ACTH and corticosterone release decline over repeated exposures to the same stimulus. In the current study we examined HPA responses to repeated psychogenic stress in 65-day-old, adult male rats that received subcutaneous capsules containing the antiandrogen flutamide or the aromatase inhibitor 1,4,6-androstatriene-3,17-dione (ATD), introduced within 12h of birth and removed on day 21 of weaning. An additional group of castrated, adult male rats were used to differentiate organizational from activational effects of testosterone. All treatment groups displayed smaller declines in ACTH in response to repeated restraint compared to control animals. Remarkably, the normal decline in corticosterone failed to occur in flutamide- and ATD-treated animals. By contrast, males that were castrated as adults showed a significant reduction in corticosterone after repeated stress. Taken together, these findings underscore an organizing influence of both androgen receptors and estrogen conversion on HPA habituation to repeated psychogenic stress, which appears to occur independent of the activational effects of testosterone.
Collapse
|
19
|
Carroll JC, Rosario ER, Kreimer S, Villamagna A, Gentzschein E, Stanczyk FZ, Pike CJ. Sex differences in β-amyloid accumulation in 3xTg-AD mice: role of neonatal sex steroid hormone exposure. Brain Res 2010; 1366:233-45. [PMID: 20934413 DOI: 10.1016/j.brainres.2010.10.009] [Citation(s) in RCA: 196] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2010] [Revised: 10/01/2010] [Accepted: 10/01/2010] [Indexed: 11/16/2022]
Abstract
The risk of Alzheimer's disease (AD) is higher in women than in men, a sex difference that likely results from the effects of sex steroid hormones. To investigate this relationship, we first compared progression of β-amyloid (Aβ) pathology in male and female triple transgenic (3xTg-AD) mice. We found that female 3xTg-AD mice exhibit significantly greater Aβ burden and larger behavioral deficits than age-matched males. Next, we evaluated how the organizational effects of sex steroid hormones during postnatal development may affect adult vulnerability to Aβ pathology. We observed that male 3xTg-AD mice demasculinized during early development exhibit significantly increased Aβ accumulation in adulthood. In contrast, female mice defeminized during early development exhibit a more male-like pattern of Aβ pathology in adulthood. Taken together, these results demonstrate significant sex differences in pathology in 3xTg-AD mice and suggest that these differences may be mediated by organizational actions of sex steroid hormones during development.
Collapse
Affiliation(s)
- Jenna C Carroll
- Neuroscience Graduate Program, University of Southern California, Los Angeles, CA 90089, USA
| | | | | | | | | | | | | |
Collapse
|
20
|
McCormick CM, Mathews IZ. HPA function in adolescence: Role of sex hormones in its regulation and the enduring consequences of exposure to stressors. Pharmacol Biochem Behav 2007; 86:220-33. [PMID: 16901532 DOI: 10.1016/j.pbb.2006.07.012] [Citation(s) in RCA: 270] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2006] [Revised: 05/24/2006] [Accepted: 07/06/2006] [Indexed: 11/27/2022]
Abstract
The hypothalamic-pituitary-adrenal (HPA) axis is one of the physiological systems involved in coping with stressors. There are functional shifts in the HPA axis and its regulation by sex hormones over the lifespan that allow the animal to meet the challenges of the internal and external environment that are specific to each stage of development. Sex differences in HPA function emerge over adolescence, a phenomenon reflecting the concomitant initiation of regulatory effects of sex hormones. The focus of this review is recent research on differences between adolescents and adults in HPA function and the enduring effects of exposure to stressors in adolescence. During adolescence, HPA function is characterized by a prolonged activation in response to stressors compared to adulthood, which may render ongoing development of the brain vulnerable. Although research has been scarce, there is a growing evidence that exposure to stressors in adolescence may alter behavioural responses to drugs and cognitive performance in adulthood. However, the effects reported appear to be stressor-specific and sex-specific. Such research may contribute toward understanding the increased risk for drug abuse and psychopathology that occurs over adolescence in people.
Collapse
Affiliation(s)
- Cheryl M McCormick
- Behavioural Neuroscience, Center for Neuroscience and Department of Psychology, Brock University, St Catharines ON, Canada.
| | | |
Collapse
|
21
|
Ward GR, Abdel-Rahman AA. Orchiectomy or androgen receptor blockade attenuates baroreflex-mediated bradycardia in conscious rats. BMC Pharmacol 2006; 6:2. [PMID: 16430770 PMCID: PMC1403759 DOI: 10.1186/1471-2210-6-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2004] [Accepted: 01/23/2006] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Previous studies have shown that testosterone enhances baroreflex bradycardia. Therefore, conscious unrestrained rats were used to investigate the role of the androgen receptor in the testosterone-mediated modulation of baroreflex bradycardia. Androgen depletion (3 weeks), and androgen receptor blockade (20-24 h), were implemented to test the hypothesis that testosterone influences baroreflex bradycardia via its activity at the androgen receptor in male rats. Phenylephrine (1-16 microg kg(-1)) was used to assess baroreflex bradycardia. RESULTS Androgen depletion attenuated baroreflex bradycardia (P < 0.01). The antiandrogen flutamide (5, 15, or 30 mg kg(-1), s.c.) caused dose-related attenuation of baroreflex bradycardia in spite of a significant (P < 0.05) increase in serum testosterone. The latter did not lead to increased serum 17beta-estradiol level. CONCLUSION The data suggest: 1) Androgen depletion or adequate androgen receptor blockade attenuates baroreflex bradycardia. 2) The reflex increase in serum testosterone may counterbalance the action of the lower doses (5 or 15 mg kg(-1)) of flutamide. 3) The absence of a change in serum 17beta-estradiol rules out its contribution to flutamide action on baroreflex bradycardia.
Collapse
Affiliation(s)
- Gregg R Ward
- Department of Pharmacology, The Brody School of Medicine at East Carolina University, Greenville, NC, 27858, USA
| | - Abdel A Abdel-Rahman
- Department of Pharmacology, The Brody School of Medicine at East Carolina University, Greenville, NC, 27858, USA
| |
Collapse
|
22
|
Abstract
Stress exposure, depending on intensity and duration, elicits adaptive or maladaptive physiological changes. The same general pattern of advantageous versus deleterious stress effects appears to exist for some cognitive functions, particularly spatial learning and memory performance. This article reviews sex differences in response to stress on a variety of spatial tasks. In general, females are more resistant than males to stress-induced impairments on spatial tasks, including the radial arm maze and object placement. In young adulthood, chronic stress (restraint, 6 h per day for 21 days) impairs male performance on both tasks but leads to behavioural enhancements in females. Furthermore, these sex-dependent stress effects are influenced by both organisational and activational oestrogenic effects. Additionally, sex-specific stress responses vary depending on developmental age at the time of stress exposure. Male behavioural stress responses appear fixed across the lifespan (i.e. stress-induced cognitive impairments) whereas female stress responses appear more variable (i.e. stress-induced enhancements observed in young adulthood are different in response to prenatal stress and diminished following stress exposure at old age). These findings underscore the point that many effects obtained in males cannot be generalised to females and highlight the need to investigate the stress response at different ages and in both sexes.
Collapse
Affiliation(s)
- R E Bowman
- Department of Psychology, Sacred Heart University, Fairfield, CT 06825, USA.
| |
Collapse
|
23
|
McCormick CM, Robarts D, Kopeikina K, Kelsey JE. Long-lasting, sex- and age-specific effects of social stressors on corticosterone responses to restraint and on locomotor responses to psychostimulants in rats. Horm Behav 2005; 48:64-74. [PMID: 15919386 DOI: 10.1016/j.yhbeh.2005.01.008] [Citation(s) in RCA: 132] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2004] [Revised: 12/22/2004] [Accepted: 01/21/2005] [Indexed: 10/25/2022]
Abstract
Many neural systems are undergoing marked development over adolescence, which may heighten an animal's vulnerability to stressors. One consequence may be altered sensitivity to drugs of abuse. We previously reported that social stressors in adolescence increased behavioral sensitization to nicotine in adulthood in female, but not male, rats. Here we examined whether social stressors in adolescence alter the functioning of the hypothalamic-pituitary-adrenal (HPA) axis by examining corticosterone release in response to restraint in adulthood. To further assess effects of social stressors on behavioral sensitivity to psychostimulants, we examined locomotor activity in response to nicotine and to amphetamine. In a second set of experiments, we investigated whether the same procedure of social stressors administered in adulthood produces effects similar to that observed when administered in adolescence. Rats underwent daily 1 h isolation followed by pairing with a new cage mate on either postnatal days 33-48 (pubertal stress: PS) or days 65-80 (adult stress: AS). Three weeks later rats tested for either: (a) corticosterone levels were measured in response to restraint, or (b) locomotor sensitization to nicotine (0.25 mg/kg; 5 days) followed by an amphetamine challenge (0.5 mg/kg) 24 h later. Effects of social stressors were evident only in females. PS females had increased locomotor activity to amphetamine compared to controls, and AS females had increased corticosterone release compared to controls. No effect of the social stressors was found in males at either age except for reduced weight gain during the stress procedure. Thus, females are more susceptible to the enduring effects of these moderate social stressors than are males. However, in terms of behavioral sensitivity to drugs of abuse, females may be more susceptible to stressors during adolescence than adulthood, although the reverse appears to be true for HPA function.
Collapse
|
24
|
Wewers D, Kaiser S, Sachser N. Application of an antiandrogen during pregnancy infantilizes the male offsprings' behaviour. Behav Brain Res 2005; 158:89-95. [PMID: 15680197 DOI: 10.1016/j.bbr.2004.08.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2004] [Revised: 08/16/2004] [Accepted: 08/16/2004] [Indexed: 11/27/2022]
Abstract
The present study was conducted to test the hypothesis that an application of an antiandrogen during pregnancy causes an infantilization of the male offsprings' behaviour later in life. The subjects studied were male guinea pigs whose mothers were either treated with an antiandrogen (flutamide and carrier) or a placebo (carrier only) during pregnancy. The mothers lived in groups of five females and one male. Application of the antiandrogen or the placebo took place on days 30, 32, 34, and 36 of pregnancy, the sensitive phase of foetal CNS sexual differentiation in guinea pigs. After weaning three groups of sons, whose mothers had received the antiandrogen (FT-sons) and five groups of sons, whose mothers had received the placebo (PT-sons) were established. Each group consisted of two males. From their 20th through their 100th day of age, the spontaneous behaviour of the males was recorded in their home cages in 5-day intervals. Additionally, blood samples were collected to determine serum cortisol concentrations. FT-sons and PT-sons did not differ in serum cortisol concentrations. However, distinct differences in behaviour occurred: FT-sons rested significantly longer with bodily contact than PT-sons. Additionally, FT-sons displayed more play-behaviour than PT-sons. These results point to a behavioural infantilization in males prenatally treated with antiandrogen. The behavioural differences between FT- and PT-sons are in accordance with previous studies in which a decrease of serum androgen concentrations in pregnant females living in an unstable social environment [Psychoneuroendocrinology 2001;26:503] and an infantilization of their sons' behaviour was described [Psychoneuroendocrinology 2003;28:67]. Thus, our study supports the hypothesis, that the decrease of androgen concentrations during pregnancy, caused by an unstable social environment, is responsible for the infantilization of the male offsprings' behaviour.
Collapse
Affiliation(s)
- Dirk Wewers
- Department of Behavioural Biology, University of Muenster, Badestr. 9, 48149 Muenster, Germany.
| | | | | |
Collapse
|
25
|
Rosene DL, Lister JP, Schwagerl AL, Tonkiss J, McCormick CM, Galler JR. Prenatal protein malnutrition in rats alters the c-Fos response of neurons in the anterior cingulate and medial prefrontal region to behavioral stress. Nutr Neurosci 2005; 7:281-9. [PMID: 15682924 DOI: 10.1080/10284150400015573] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Prenatal protein malnutrition affects brain development and behavior despite dietary rehabilitation from birth. Behavioral alterations include abnormal responses to stressors. To explore what brain regions mediate this altered response, we used immunocytochemistry to c-Fos protein, a transcription factor marking neuronal activation. Controls (25% casein diet) and prenatally malnourished (6% casein) adult rats were subjected to 20min of restraint stress or were unstressed. Plasma corticosterone levels were monitored before and after stress. Paired comparisons of corticosterone levels confirmed that both groups showed a significant post-stress increase. Three hours after onset of stress, rats were perfused with paraformaldehyde. Brain sections were immuno-stained together for c-Fos. Since anterior cingulate and medial prefrontal cortex modulate stress responses, labeled neurons in this region were quantified using unbiased stereology. A 2-way ANOVA of neuron numbers demonstrated a strong effect of stress and a stress by nutrition interaction. Post-hoc comparisons showed that stress significantly increased the number of c-Fos labeled neurons in both nutrition groups. Within the stress condition, prenatally malnourished rats showed a significantly greater number of c-Fos positive neurons than well-nourished rats. These results suggest that neurons in anterior cingulate and medial prefrontal regions respond excessively to restraint stress in prenatally malnourished rats.
Collapse
Affiliation(s)
- Douglas L Rosene
- Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, MA 02118, USA.
| | | | | | | | | | | |
Collapse
|
26
|
Knuth ED, Etgen AM. Corticosterone secretion induced by chronic isolation in neonatal rats is sexually dimorphic and accompanied by elevated ACTH. Horm Behav 2005; 47:65-75. [PMID: 15579267 DOI: 10.1016/j.yhbeh.2004.08.011] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2003] [Revised: 06/08/2004] [Accepted: 08/18/2004] [Indexed: 11/20/2022]
Abstract
Rat pups repeatedly subjected to brief periods of isolation during the stress hyporesponsive period (SHRP) exhibit varied neuroendocrine and behavioral changes as neonates and as adults. For example, neonatal rats exhibit increased circulating corticosterone after 1-h isolation on postnatal day 9 (P9) only if they were isolated daily from P2 to P8 [McCormick, C.M., Kehoe, P., Kovacs, S., 1998. Corticosterone release in response to repeated, short episodes of neonatal isolation: evidence of sensitization. Int. J. Dev. Neurosci. 16, 175-185]. It is not known if the increase in adrenocortical response on P9 following repeated isolation is mediated by increased pituitary ACTH secretion. The present study examined the responsivity of the hypothalamic-pituitary-adrenal (HPA) axis during the SHRP following brief, repeated isolation or acute pharmacological manipulation. Removal from the nest for 1 h daily on P4-8 increased circulating corticosterone after 1-h isolation on P9 by approximately twofold. Neither unhandled nor handled controls showed a corticosterone response to 1-h isolation on P9. The increased corticosterone was sexually dimorphic, with only females showing the sensitization response. Other findings suggest that the hormonal response is centrally mediated; chronically isolated pups of both sexes exhibit increased plasma ACTH following 1-h isolation on P9. While we could not detect an increase in Fos immunoreactivity (IR) on P9 in the hypothalamic paraventricular nucleus (PVN) of chronically isolated pups, acute pharmacological activation of serotonin 2A/2C receptors produced robust activation of ACTH and corticosterone secretion as well as expression of Fos in the PVN on P9. We conclude that chronic isolation stress limited to the SHRP stimulates the neonatal HPA axis, and that the adrenal response is sexually dimorphic. In addition, PVN neurons can express Fos IR on P9 in response to a very potent activation of the HPA axis.
Collapse
Affiliation(s)
- Emily D Knuth
- Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | | |
Collapse
|
27
|
McCormick CM, Robarts D, Gleason E, Kelsey JE. Stress during adolescence enhances locomotor sensitization to nicotine in adulthood in female, but not male, rats. Horm Behav 2004; 46:458-66. [PMID: 15465532 DOI: 10.1016/j.yhbeh.2004.05.004] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2003] [Revised: 04/28/2004] [Accepted: 05/21/2004] [Indexed: 10/26/2022]
Abstract
A wide body of research has indicated that perinatal exposure to stressors alters the organism, notably by programming behavioral and neuroendocrine responses and sensitivity to drugs of abuse in adulthood. Recent evidence suggests that adolescence also may represent a sensitive period of brain development, and yet there has been little research on the long-lasting effects of stressors during this period. We investigated the effects of pubertal social stress (PS; daily 1-h isolation followed by pairing with a new cage mate on postnatal days 33-48) on locomotor sensitization to injections of nicotine and corticosterone response to restraint stress when the rats were adults (approximately 3 weeks after PS). There were no differences among the groups in locomotor activity to injections of saline. However, PS females had enhanced locomotor sensitization to repeated doses of nicotine compared to control (non-stressed; NS) females, whereas PS males and NS males did not differ. PS enhanced the corticosterone response to restraint in male rats previously sensitized to nicotine and decreased the corticosterone response in nonsensitized male rats. In contrast, PS females and NS females did not differ in plasma corticosterone levels in response to restraint stress, but NS females showed enhanced corticosterone release to restraint after sensitization to nicotine. Thus, during adolescence, social stressors can have long-lasting effects, and the effects appear to differ for males and females.
Collapse
|
28
|
RE: THE EFFECTS OF COMBINED ANDROGEN BLOCKADE ON COGNITIVE FUNCTION DURING THE FIRST CYCLE OF INTERMITTENT ANDROGEN SUPPRESSION IN PATIENTS WITH PROSTATE CANCER: Reply by Authors. J Urol 2004. [DOI: 10.1016/s0022-5347(05)61739-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
29
|
Gardiner RA, Nicol DL, Green HJ, Yaxley J, Watson R, Mactaggart P, Headley BC, Swanson C, Pakenham KI. RE: THE EFFECTS OF COMBINED ANDROGEN BLOCKADE ON COGNITIVE FUNCTION DURING THE FIRST CYCLE OF INTERMITTENT ANDROGEN SUPPRESSION IN PATIENTS WITH PROSTATE CANCER. J Urol 2004; 172:774; author reply 774-5. [PMID: 15247782 DOI: 10.1097/01.ju.0000132508.20023.08] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
30
|
Shors TJ, Miesegaes G. Testosterone in utero and at birth dictates how stressful experience will affect learning in adulthood. Proc Natl Acad Sci U S A 2002; 99:13955-60. [PMID: 12359876 PMCID: PMC129804 DOI: 10.1073/pnas.202199999] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2002] [Indexed: 11/18/2022] Open
Abstract
Exposure to an acute stressful event can enhance learning in male rats, whereas exposure to the same event dramatically impairs performance in females. Here we tested whether the presence of sex hormones during early development organizes these opposite effects of stress on learning in males vs. females. In the first experiment, males were castrated at birth whereas females were injected with testosterone. Rats were trained as adults on the hippocampal-dependent learning task of trace eyeblink conditioning. Performance in adult males that had been castrated at birth was still enhanced by exposure to an acute stressful experience. However, adult females injected with testosterone at birth responded in the opposite direction, i.e., exposure to the stressor that typically reduces performance instead enhanced their levels of conditioning. In the second experiment, exposure to testosterone was manipulated in utero by injecting pregnant females with a testosterone antagonist. After foster rearing, adult offspring were exposed to the stressor and trained on the hippocampal-dependent learning task of trace conditioning. Although performance in adult females was unaffected by antagonizing testosterone in utero, i.e., stress still reduced performance, the enhancement of conditioning after stress in adult males was prevented. Thus, the presence of sex hormones during gestation and development organizes whether and how acute stressful experience will affect the ability to acquire new information in adulthood. As with many sexual behaviors, these cognitive responses to stress appear to be masculinized by exposure to testosterone and feminized by its absence during very early development.
Collapse
Affiliation(s)
- Tracey J Shors
- Department of Psychology and Center for Collaborative Neuroscience, Rutgers University, Piscataway, NJ 08854-8020, USA.
| | | |
Collapse
|
31
|
McCormick CM, Kehoe P, Mallinson K, Cecchi L, Frye CA. Neonatal isolation alters stress hormone and mesolimbic dopamine release in juvenile rats. Pharmacol Biochem Behav 2002; 73:77-85. [PMID: 12076726 DOI: 10.1016/s0091-3057(02)00758-x] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Rat pups were individually isolated from the mother and nest for 1 h/day from postnatal days (PND) 2 to 9 and tested as juveniles (PND 26-30) compared to nonhandled (NH) controls. In response to 1 h of restraint stress, NH rats increased locomotor activity and dopamine (DA) levels, but neonatally isolated (ISO) rats did not. Both groups had increased plasma corticosterone levels in response to restraint, but corticosterone levels were higher in ISO than in NH. Brain allopregnanolone (3alpha,5alpha-THP) levels also increased in response to stress, but NH and ISO did not differ. Sex of the rats was not a factor for any of the measures except plasma corticosterone levels, where females had higher levels than males. These data indicate that the effects of neonatal isolation persist postweaning and that the effects are most evident in response to stress as opposed to under baseline conditions.
Collapse
Affiliation(s)
- Cheryl M McCormick
- Neuroscience Program and Department of Psychology, Bates College, Lewiston, ME 04240, USA.
| | | | | | | | | |
Collapse
|
32
|
Green PG, Dahlqvist SR, Isenberg WM, Miao FJ, Levine JD. Role of adrenal medulla in development of sexual dimorphism in inflammation. Eur J Neurosci 2001; 14:1436-44. [PMID: 11722605 DOI: 10.1046/j.0953-816x.2001.01768.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Many inflammatory diseases show a female predilection in adults, but not prepubertally. Because sex differences in the inflammatory response in the adult rat are mediated, in part, by sexual dimorphism in adrenal medullary function, we investigated the contribution of the adrenal medulla to the ontogeny of sexual dimorphism in inflammation. Whilst there was no sex difference in the magnitude of the plasma extravasation (PE) induced by the potent inflammatory mediator bradykinin (BK) in prepubertal rats, in adult rats BK-induced PE was markedly greater in males. Also, adult male rats, gonadectomized prior to puberty, had a lower magnitude of BK-induced PE than did adult male controls, whilst adult females gonadectomized prepubertally had higher BK-induced PE than did controls. In rats gonadectomized after puberty, the magnitude of BK-induced PE in adult males was not affected, whilst in females it resulted in significantly higher BK-induced PE, similar to the effect of prepubertal gonadectomy. When tested prepubertally, adrenal denervation increased the magnitude of BK-induced PE in females, but not in males. In contrast, in both males and females tested as adults, but castrated prepubertally, and in gonad-intact adult females, adrenal denervation significantly increased the magnitude of BK-induced PE. Adrenal denervation in prepubertal females given adult levels of 17beta-oestradiol produced a marked enhancement in the denervation-induced increase in magnitude of BK-induced PE compared to females not exposed prematurely to sex hormones. These studies suggest that an adrenal medulla-dependent inhibition of BK-induced PE is present in female but not male rats, and is enhanced by oestrogen but suppressed by testosterone.
Collapse
Affiliation(s)
- P G Green
- Department of Oral and Maxillofacial Surgery, Obstetrics Gynecology and Reproductive Sciences and Medicine, University of California San Francisco, San Francisco, California 94143-0440, USA.
| | | | | | | | | |
Collapse
|
33
|
McCormick CM, Rioux T, Fisher R, Lang K, MacLaury K, Teillon SM. Effects of neonatal corticosterone treatment on maze performance and HPA axis in juvenile rats. Physiol Behav 2001; 74:371-9. [PMID: 11714502 DOI: 10.1016/s0031-9384(01)00574-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Previous research has indicated that administering corticosterone to dams' drinking water for 21 days produced persistent alterations in physiology and behavior. We investigated whether 4 days of corticosterone exposure would have similar effects, and whether greater effects would be found when corticosterone was administered early in neonatal life than later in neonatal life. Sprague-Dawley dams were given either corticosterone (250 microg/ml) in their water bottles for postnatal days (PND) 5-9 (early corticosterone treatment: ECT), PND 13-17 (late corticosterone treatment: LCT) or no treatment (NT). At the end of treatment, corticosterone levels were higher in pups of corticosterone drinking dams. However, at weaning, ECT and LCT pups had lower basal corticosterone levels than NT pups. As juveniles, ECT pups learned to navigate to a visible and then to a nonvisible platform in a Morris water maze more quickly than did LCT and NT pups. Among females, ECT pups had higher corticosterone release in response to stress than LCT and NT pups. There were no differences in hippocampal corticosteroid receptor levels among the groups. The pattern of results is similar to, but not identical to, that found for pups exposed to corticosterone for 21 days. The results also suggest that there is a critical or sensitive period for corticosterone treatment in that early treatment was more effective than later treatment.
Collapse
Affiliation(s)
- C M McCormick
- Neuroscience Program and Department of Psychology, Bates College, Lewiston, ME 04240, USA.
| | | | | | | | | | | |
Collapse
|
34
|
Ward IL, Bennett AL, Ward OB, Hendricks SE, French JA. Androgen threshold to activate copulation differs in male rats prenatally exposed to alcohol, stress, or both factors. Horm Behav 1999; 36:129-40. [PMID: 10506537 DOI: 10.1006/hbeh.1999.1534] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Few male rats prenatally exposed to a combination of alcohol and stress copulate spontaneously. This study determined adult sensitivity to testosterone (T) in males prenatally exposed to alcohol, to stress, or to both factors. Sexually naive males were tested with receptive females following castration and implantation of 20-, 30-, or 45-mm Silastic T-filled capsules. Serum T levels provided by these implants were measured. The behavior shown by males exposed only to prenatal alcohol did not differ from untreated control animals at any T dosage. Prenatal stress alone diminished the copulatory potential below control levels only when the intermediate T dosage was provided. Few males exposed to both alcohol and stress copulated under the lowest or the intermediate dose of adult T replacement, but most ejaculated normally when the largest capsule was implanted. The threshold to the sexual behavior-activating-properties of adult T exposure was moderately raised by prenatal stress but was severely affected when prenatal stress was combined with alcohol. We conclude that a diminished sensitivity to androgen in adulthood underlies some copulatory deficits resulting from treatments that alter fetal T levels. Such deficits may be concealed when behavior is evaluated in gonadally intact animals.
Collapse
Affiliation(s)
- I L Ward
- Department of Psychology, Villanova University, Villanova, Pennsylvania, 19085, USA.
| | | | | | | | | |
Collapse
|