1
|
Alonge MM, Greville LJS, Ma X, Faure PA, Bentley GE. Acute restraint stress rapidly impacts reproductive neuroendocrinology and downstream gonad function in big brown bats (Eptesicus fuscus). J Exp Biol 2023; 226:jeb245592. [PMID: 37827114 PMCID: PMC10629485 DOI: 10.1242/jeb.245592] [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: 01/31/2023] [Accepted: 08/23/2023] [Indexed: 10/14/2023]
Abstract
Animals face unpredictable challenges that require rapid, facultative physiological reactions to support survival but may compromise reproduction. Bats have a long-standing reputation for being highly sensitive to stressors, with sensitivity and resilience varying both within and among species, yet little is known about how stress affects the signaling that regulates reproductive physiology. Here, we provide the first description of the molecular response of the hypothalamic-pituitary-gonadal (HPG) axis of male big brown bats (Eptesicus fuscus) in response to short-term stress using a standardized restraint manipulation. This acute stressor was sufficient to upregulate plasma corticosterone and resulted in a rapid decrease in circulating testosterone. While we did not find differences in the mRNA expression of key steroidogenic enzymes (StAR, aromatase, 5-alpha reductase), seminiferous tubule diameter was reduced in stressed bats coupled with a 5-fold increase in glucocorticoid receptor (GR) mRNA expression in the testes. These changes, in part, may be mediated by RFamide-related peptide (RFRP) because fewer immunoreactive cell bodies were detected in the brains of stressed bats compared with controls - suggesting a possible increase in secretion - and increased RFRP expression locally in the gonads. The rapid sensitivity of the bat testes to stress may be connected to deleterious impacts on tissue health and function as supported by significant transcriptional upregulation of key pro-apoptotic signaling molecules (Bax, cytochrome c). Experiments like this broadly contribute to our understanding of the stronger ecological predictions regarding physiological responses of bats within the context of stress, which may impact decisions surrounding animal handling and conservation approaches.
Collapse
Affiliation(s)
- Mattina M. Alonge
- University of California, Berkeley, Department of Integrative Biology, Berkeley, CA 94720-3200, USA
| | - Lucas J. S. Greville
- McMaster University, Department of Psychology, Neuroscience & Behaviour, Hamilton, ON, Canada, L8S 4L8
- University of Waterloo, Department of Biology, Waterloo, ON, Canada, N2L 3G1
| | - Xuehao Ma
- University of California, Berkeley, Department of Integrative Biology, Berkeley, CA 94720-3200, USA
- Helen Wills Neuroscience Institute, Berkeley, CA 94720, USA
| | - Paul A. Faure
- McMaster University, Department of Psychology, Neuroscience & Behaviour, Hamilton, ON, Canada, L8S 4L8
| | - George E. Bentley
- University of California, Berkeley, Department of Integrative Biology, Berkeley, CA 94720-3200, USA
- Helen Wills Neuroscience Institute, Berkeley, CA 94720, USA
| |
Collapse
|
2
|
Xu Y, Li W, Shi M, Xu X, Guo D, Liu Z, Chen L, Zhong X, Cao W. Systemic treatment with GnRH agonist produces antidepressant-like effects in LPS induced depression male mouse model. Neuropharmacology 2023; 233:109560. [PMID: 37094770 DOI: 10.1016/j.neuropharm.2023.109560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Revised: 04/18/2023] [Accepted: 04/20/2023] [Indexed: 04/26/2023]
Abstract
Gonadotropin-releasing hormone (GnRH) is at the head of the neuroendocrine reproductive axis. However, the non-reproductive functions of GnRH expressed in various tissues, including hippocampus, are still not known. Here, we unveil a previously unknown effect of GnRH, which mediates depression-like behaviors through the modulation of microglia function during immune challenge. Specifically, we found that either systemic treatment with GnRH agonist or over-expression of endogenous hippocampal GnRH via viral tool abolished the depression-like behavior after LPS challenges in mice. And the anti-depressant of GnRH was dependent on the hippocampal GnRHR signaling, since antagonizing GnRHR by drug treatment or by hippocampal GnRHR knockdown could block the antidepressant-effect of GnRH agonist. Interestingly, we found that the peripheral GnRH treatment prevented the microglia activation mediated inflammation in the hippocampus of mice. In light of the research findings presented here, we propose that, at least in the hippocampus, GnRH appears to act on GnRHR to regulate higher order non-reproductive functions associated with the microglia mediated neuroinflammation. These findings also provide insights into the function and cross-talk of GnRH, a known neuropeptide hormone, in neuro-immune response.
Collapse
Affiliation(s)
- Yang Xu
- Institute of Neuroscience, Hengyang Medical School, University of South China, Hengyang, 421001, Hunan, China
| | - Wei Li
- Department of Human Anatomy, Hengyang Medical School, University of South China, Hengyang, 421001, Hunan, China
| | - Mengmeng Shi
- Department of Human Anatomy, Hengyang Medical School, University of South China, Hengyang, 421001, Hunan, China
| | - Xiaofan Xu
- Department of Human Anatomy, Hengyang Medical School, University of South China, Hengyang, 421001, Hunan, China
| | - Dongmin Guo
- Department of Human Anatomy, Hengyang Medical School, University of South China, Hengyang, 421001, Hunan, China
| | - Zhenghai Liu
- Department of Human Anatomy, Hengyang Medical School, University of South China, Hengyang, 421001, Hunan, China
| | - Ling Chen
- Department of Metabolism and Endocrinology, The First Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, 421001, Hunan, China
| | - Xiaolin Zhong
- Department of Metabolism and Endocrinology, The First Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, 421001, Hunan, China.
| | - Wenyu Cao
- Department of Human Anatomy, Hengyang Medical School, University of South China, Hengyang, 421001, Hunan, China.
| |
Collapse
|
3
|
Gautam P, Ajit K, Das M, Taliyan R, Roy R, Banerjee A. Age-related changes in gonadotropin-releasing hormone (GnRH) splice variants in mouse brain. JOURNAL OF EXPERIMENTAL ZOOLOGY. PART A, ECOLOGICAL AND INTEGRATIVE PHYSIOLOGY 2023; 339:193-209. [PMID: 36336790 DOI: 10.1002/jez.2671] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 09/07/2022] [Accepted: 10/07/2022] [Indexed: 11/09/2022]
Abstract
Gonadotropin-releasing hormone (GnRH) is the primary regulator of the mammalian reproductive axis. We investigated the spatiotemporal expression of GnRH splice variants (V1, V2, and V3) and splicing factors (Srsf7, Srsf9, and Tra-2) in the male mice brain. Further, using in silico tools, we predicted protein structure and the reason for the low translational efficiency of V2 and V3. Messenger RNA levels of GnRH variants and splicing factors were quantified using real-time reverse transcription-polymerase chain reaction at different age groups. Our data show that expression of almost all the variants alters with aging in all the brain regions studied; even in comparison to the hypothalamus, several brain areas were found to have higher expression of these variants. Hypothalamic expression of splicing factors such as Srsf7, Srsf9, and Tra-2 also change with aging. Computational studies have translation repressors site on the V3, which probably reduces its translation efficiency. Also, V2 is an intrinsically disordered protein that might have a regulatory or signaling function. In conclusion, this study provides novel crucial information and multiple starting points for future analysis of GnRH splice variants in the brain.
Collapse
Affiliation(s)
- Pooja Gautam
- Department of Biological Sciences, BITS Pilani, KK Birla, Goa Campus, Goa, India
| | - Kamal Ajit
- Department of Biological Sciences, BITS Pilani, KK Birla, Goa Campus, Goa, India
| | - Moitreyi Das
- Department of Zoology, Goa University, Goa, India
| | - Rajeev Taliyan
- Department of Pharmacy, BITS Pilani, Pilani Campus, Rajasthan, India
| | | | - Arnab Banerjee
- Department of Biological Sciences, BITS Pilani, KK Birla, Goa Campus, Goa, India
| |
Collapse
|
4
|
Sex neurosteroids: Hormones made by the brain for the brain. Neurosci Lett 2021; 753:135849. [PMID: 33775739 DOI: 10.1016/j.neulet.2021.135849] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 03/09/2021] [Accepted: 03/22/2021] [Indexed: 11/21/2022]
Abstract
In general, hippocampal neurons are capable of synthesizing sex steroids de novo from cholesterol, since the brain is equipped with all the enzymes required for the synthesis of estradiol and testosterone, the end products of sex steroidogenesis. Regarding estradiol, its synthesis in hippocampal neurons is homeostatically controlled by Ca2+ transients and is regulated by GnRH. Locally synthesized estradiol and testosterone maintain synaptic transmission and synaptic connectivity. Remarkably, the neurosteroid estradiol is effective in females, but not in males, and vice versa dihydrotestosterone (DHT) is effective in males, but not in females. Experimentally induced inhibition of estradiol synthesis in females and DHT synthesis in males resp. results in synapse loss, impaired LTP, and downregulation of synaptic proteins. GnRH-induced increase in estradiol synthesis appears to provide a link between the hypothalamus and the hippocampus, which may underlie estrous cyclicity of spine density in the female hippocampus. Hippocampal neurons are sex-dependently differentiated with respect to the responsiveness of hippocampal neurons to sex neurosteroids.
Collapse
|
5
|
DuRant S, Love AC, Belin B, Tamayo-Sanchez D, Santos Pacheco M, Dickens MJ, Calisi RM. Captivity alters neuroendocrine regulators of stress and reproduction in the hypothalamus in response to acute stress. Gen Comp Endocrinol 2020; 295:113519. [PMID: 32470473 DOI: 10.1016/j.ygcen.2020.113519] [Citation(s) in RCA: 7] [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: 11/13/2019] [Revised: 02/26/2020] [Accepted: 05/22/2020] [Indexed: 01/19/2023]
Abstract
Wild animals are brought into captivity for many reasons. However, unlike laboratory-bred animals, wild caught animals often respond to the dramatic shift in their environment with physiological changes in the stress and reproductive pathways. Using wild-caught male and female house sparrows (Passer domesticus) we examined how time in captivity affects the expression of reproductive and stress-associated genes in the brain, specifically, the hypothalamus. We quantified relative mRNA expression of a neurohormone involved in the stress response (corticotropin releasing hormone [CRH]), a hypothalamic inhibitor of reproduction (gonadotropin inhibitory hormone [GnIH]), and the glucocorticoid receptor (GR), which is important in terminating the stress response. To understand potential shifts at the cellular level, we also examined the presence of hypothalamic GnIH (GnIH-ir) using immunohistochemistry. We hypothesized that expression of these genes and the abundance of cells immunoreactive for GnIH would change in response to time in captivity as compared to free-living individuals. We found that GR mRNA expression and GnIH-ir cell abundance increased after 24 and 45 days in captivity, as compared to wild-caught birds. At 66 days in captivity, GR expression and GnIH cell abundance did not differ from wild-caught birds, suggesting birds had acclimated to captivity. Evaluation of CRH and GnIH mRNA expression yielded similar trends, though they were not statistically significant. In addition, although neuroendocrine factors appeared to acclimate to captivity, a previous study indicated that corticosterone release and immune responses of these same birds did not acclimate to captivity, suggesting that neuroendocrine endpoints may adapt more rapidly to captivity than downstream physiological measures. These data expand our understanding of the physiological shifts occurring when wild animals are brought into captivity.
Collapse
Affiliation(s)
- Sarah DuRant
- Department of Biological Sciences, University of Arkansas, Fayetteville, AR 72701, United States.
| | - Ashley C Love
- Department of Biological Sciences, University of Arkansas, Fayetteville, AR 72701, United States; Department of Integrative Biology, Oklahoma State University, Stillwater, OK 74074, United States
| | - Bryana Belin
- Department of Biology, Program in Neuroscience and Behavior, Barnard College of Columbia University, New York, NY 10027, United States
| | - Doris Tamayo-Sanchez
- Department of Biology, Program in Neuroscience and Behavior, Barnard College of Columbia University, New York, NY 10027, United States
| | - Michelle Santos Pacheco
- Department of Biology, Program in Neuroscience and Behavior, Barnard College of Columbia University, New York, NY 10027, United States
| | - Molly J Dickens
- Department of Integrative Biology, University of California, Berkeley, CA 94720, United States
| | - Rebecca M Calisi
- Department of Biology, Program in Neuroscience and Behavior, Barnard College of Columbia University, New York, NY 10027, United States; Department of Neurobiology, Physiology and Behavior, University of California, Davis, CA 95616, United States
| |
Collapse
|
6
|
Low KL, Tomm RJ, Ma C, Tobiansky DJ, Floresco SB, Soma KK. Effects of aging on testosterone and androgen receptors in the mesocorticolimbic system of male rats. Horm Behav 2020; 120:104689. [PMID: 31954104 DOI: 10.1016/j.yhbeh.2020.104689] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2019] [Revised: 11/23/2019] [Accepted: 01/10/2020] [Indexed: 12/18/2022]
Abstract
As males age, systemic testosterone (T) levels decline. T regulates executive function, a collection of cognitive processes that are mediated by the mesocorticolimbic system. Here, we examined young adult (5 months) and aged (22 months) male Fischer 344 × Brown Norway rats, and measured systemic T levels in serum and local T levels in microdissected nodes of the mesocorticolimbic system (ventral tegmental area (VTA), nucleus accumbens (NAc), medial prefrontal cortex (mPFC), and orbitofrontal cortex (OFC)). We also measured androgen receptor (AR) immunoreactivity (-ir) in the mesocorticolimbic system. As expected, systemic T levels decreased with age. Local T levels in mesocorticolimbic regions - except the VTA - also decreased with age. Mesocorticolimbic T levels were higher than serum T levels at both ages. AR-ir was present in the VTA, NAc, mPFC, and OFC and decreased with age in the mPFC. Taken together with previous results, the data suggest that changes in androgen signaling may contribute to changes in executive function during aging.
Collapse
Affiliation(s)
- Katelyn L Low
- Department of Psychology and Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC, Canada; Department of Zoology, University of British Columbia, Vancouver, BC, Canada
| | - Ryan J Tomm
- Department of Psychology and Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC, Canada
| | - Chunqi Ma
- Department of Psychology and Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC, Canada
| | - Daniel J Tobiansky
- Department of Psychology and Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC, Canada
| | - Stan B Floresco
- Department of Psychology and Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC, Canada
| | - Kiran K Soma
- Department of Psychology and Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC, Canada; Department of Zoology, University of British Columbia, Vancouver, BC, Canada.
| |
Collapse
|
7
|
Fernandes JRD, Moitra A, Tsutsui K, Banerjee A. Regulation of the hypothalamic GnRH-GnIH system by putrescine in adult female rats and GT1-7 neuronal cell line. JOURNAL OF EXPERIMENTAL ZOOLOGY PART 2020; 333:214-229. [PMID: 32039555 DOI: 10.1002/jez.2351] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2019] [Revised: 01/06/2020] [Accepted: 01/08/2020] [Indexed: 12/20/2022]
Abstract
The gonadotropin-releasing hormone-gonadotropin inhibitor (GnRH-GnIH) system in the hypothalamus of mammals is the key factor that controls the entire reproductive system. The aim of this study was to immunolocalize GnIH (RFRP-3) in the hypothalamus during the estrous cycle and to study the effect of putrescine on the expression of GnRH-I and GnIH through both in vivo and in vitro (GT1-7 cells) approach and the circulatory levels of GnRH-I, GnIH, and gonadotropins were also investigated. The study also aims in analyzing all the immunofluorescence images by measuring the relative pixel count of an image. This study showed the effect of putrescine on the morphology of ovary, uterus, and the expression of the steroidogenic acute regulatory protein in the ovary. This study showed GnIH expression was intense during the diestrus and moderate during proestrus and estrus, whereas mild staining during the metestrus. The study further showed that putrescine supplementation to adult female rats increased both GnRH-I expression in the hypothalamus as well as the GnRH-I levels in circulation. The study, for the first time, also showed that putrescine supplementation decreased the expression and release of GnIH. These effects of upregulating GnRH-I expression and downregulating GnIH expression were confirmed by in vitro experiments using GT1-7 cells. Putrescine supplementation also increased the gonadotropin levels in the serum. To summarize, putrescine can regulate the hypothalamic-pituitary-gonadal axis by increasing the GnRH-I, luteinizing hormone, and follicle-stimulating hormone levels and suppressing GnIH levels. This is the first report showing the simultaneous effects of putrescine on the regulation of both GnRH-I and GnIH in the hypothalamus.
Collapse
Affiliation(s)
- Joseph R D Fernandes
- Department of Biological Sciences, KK Birla Goa Campus, BITS Pilani, Zuarinagar, Goa, India
| | - Abhishek Moitra
- Department of Electrical and Electronics Engineering, KK Birla Goa Campus, BITS Pilani, Zuarinagar, Goa, India
| | - Kazuyoshi Tsutsui
- Laboratory of Integrative Brain Sciences, Department of Biology, Center for Medical Life Science of Waseda University, Waseda University, Tokyo, Japan
| | - Arnab Banerjee
- Department of Biological Sciences, KK Birla Goa Campus, BITS Pilani, Zuarinagar, Goa, India
| |
Collapse
|
8
|
Choi I, Rickert E, Fernandez M, Webster NJG. SIRT1 in Astrocytes Regulates Glucose Metabolism and Reproductive Function. Endocrinology 2019; 160:1547-1560. [PMID: 31127273 PMCID: PMC6542483 DOI: 10.1210/en.2019-00223] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Accepted: 04/19/2019] [Indexed: 12/13/2022]
Abstract
Sirtuin 1 (Sirt1) is an NAD-dependent class III deacetylase that functions as a cellular energy sensor. In addition to its well-characterized effects in peripheral tissues, evidence suggests that SIRT1 in neurons plays a role in the central regulation of energy balance and reproduction, but no studies have addressed the contribution of astrocytes. We show here that overexpression of SIRT1 in astrocytes causes markedly increased food intake, body weight gain, and glucose intolerance, but expression of a deacetylase-deficient SIRT1 mutant decreases food intake and body weight and improves glucose tolerance, particularly in female mice. Paradoxically, the effect of these SIRT1 mutants on insulin tolerance was reversed, with overexpression showing greater insulin sensitivity. The mice overexpressing SIRT1 were more active, generated more heat, and had elevated oxygen consumption, possibly in compensation for the increased food intake. The female overexpressing mice were also more sensitive to diet-induced obesity. Reproductively, the mice expressing the deacetylase-deficient SIRT1 mutant had impaired estrous cycles, decreased LH surges, and fewer corpora lutea, indicating decreased ovulation. The GnRH neurons were responsive to kisspeptin stimulation, but hypothalamic expression of Kiss1 was reduced in the mutant mice. Our results showed that SIRT1 signaling in astrocytes can contribute to metabolic and reproductive regulation independent of SIRT1 effects in neurons.
Collapse
Affiliation(s)
- Irene Choi
- VA San Diego Healthcare System, San Diego, California
| | - Emily Rickert
- Department of Medicine, School of Medicine, University of California San Diego, La Jolla, California
| | - Marina Fernandez
- Department of Medicine, School of Medicine, University of California San Diego, La Jolla, California
| | - Nicholas J G Webster
- VA San Diego Healthcare System, San Diego, California
- Department of Medicine, School of Medicine, University of California San Diego, La Jolla, California
- Moores Cancer Center, University of California San Diego, La Jolla, California
- Correspondence: Nicholas J. G. Webster, PhD, Department of Medicine, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093. E-mail:
| |
Collapse
|
9
|
Ullah R, Batool A, Wazir M, Naz R, Rahman TU, Wahab F, Shahab M, Fu J. Gonadotropin inhibitory hormone and RF9 stimulate hypothalamic-pituitary-adrenal axis in adult male rhesus monkeys. Neuropeptides 2017; 66:1-7. [PMID: 28757099 DOI: 10.1016/j.npep.2017.07.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Revised: 07/19/2017] [Accepted: 07/23/2017] [Indexed: 12/17/2022]
Abstract
Stress activates gonadotropin inhibitory hormone (GnIH), hypothalamic-pituitary-adrenal axis (HPA-axis) and represses hypothalamic-pituitary-gonadal axis (HPG-axis) but RF9 administration relieves stress-induced repression of the HPG-axis. Importantly, it was not known whether GnIH signaling and RF9 synthetic peptide modulate the HPA axis. To assess this, mammalian orthologs of GnIH (RFRP-1 and RFRP-3) and RF9 were administered to intact adult male rhesus monkeys. RFRP-1 (125μg/animal), RFRP-3 (250μg/animal) and RF9 (0.1mg/kg BW) were intravenously (iv) injected into normal fed (n=4) monkeys. Additionally, a single bolus iv injection of RF9 (0.1mg/kg BW) was also administered to 48h fasted monkeys (n=4) to check the effects of RF9 signaling on an activated HPA-axis. Serial blood samples were collected, centrifuged and the obtained plasma was used for the analysis of cortisol by specific enzyme immunoassay. RFRP-1 treatment significantly increased cortisol levels while RFRP-3 increased the plasma cortisol, but the effect was non-significant. RF9 treatment significantly increased cortisol levels in normal fed animals. In contrast, RF9 injection did not significantly alter circulating cortisol in fasted monkeys. In conclusion, our results suggest stimulatory action of RFRPs and RF9 on the HPA axis in the adult male monkeys. However, the mechanism and site of action of RFRP-1 and RF9 along the HPA-axis is still unknown. Therefore, further studies are needed to decipher the mechanism and site of action of RFRPs and RF9 on the HPA axis in primates.
Collapse
Affiliation(s)
- Rahim Ullah
- Department of Endocrinology, Children's Hospital of Zhejiang University School of Medicine, Hangzhou 310051, China; Laboratory of Reproductive Neuroendocrinology, Department of Animal Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan
| | - Aalia Batool
- Laboratory of Reproductive Neuroendocrinology, Department of Animal Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan; The State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing 100101, China
| | - Madiha Wazir
- Laboratory of Reproductive Neuroendocrinology, Department of Animal Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan
| | - Rabia Naz
- Laboratory of Reproductive Neuroendocrinology, Department of Animal Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan
| | - Tanzil Ur Rahman
- Laboratory of Reproductive Neuroendocrinology, Department of Animal Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan; Department of Pathology and Pathophysiology, Key Laboratory of Reproductive Genetics, School of Medicine, Zhejiang University, Hangzhou 310058, China
| | - Fazal Wahab
- Platform Degenerative Diseases, German Primate Center, Leibniz Institute for Primate Research, Kellnerweg 4, D-37077 Göttingen, Germany
| | - Muhammad Shahab
- Laboratory of Reproductive Neuroendocrinology, Department of Animal Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan.
| | - Junfen Fu
- Department of Endocrinology, Children's Hospital of Zhejiang University School of Medicine, Hangzhou 310051, China.
| |
Collapse
|
10
|
Fernandez MO, Hsueh K, Park HT, Sauceda C, Hwang V, Kumar D, Kim S, Rickert E, Mahata S, Webster NJG. Astrocyte-Specific Deletion of Peroxisome-Proliferator Activated Receptor- γ Impairs Glucose Metabolism and Estrous Cycling in Female Mice. J Endocr Soc 2017; 1:1332-1350. [PMID: 29264458 PMCID: PMC5686676 DOI: 10.1210/js.2017-00242] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Accepted: 09/15/2017] [Indexed: 01/21/2023] Open
Abstract
Mice lacking peroxisome-proliferator activated receptor-γ (PPARγ) in neurons do not become leptin resistant when placed on a high-fat diet (HFD). In male mice, this results in decreased food intake and increased energy expenditure, causing reduced body weight, but this difference in body weight is not observed in female mice. In addition, estrous cycles are disturbed and the ovaries present with hemorrhagic follicles. We observed that PPARγ was more highly expressed in astrocytes than neurons, so we created an inducible, conditional knockout of PPARγ in astrocytes (AKO). The AKO mice had impaired glucose tolerance and hepatic steatosis that did not worsen with HFD. Expression of gluconeogenic genes was elevated in the mouse livers, as was expression of several genes involved in lipogenesis, lipid transport, and storage. The AKO mice also had a reproductive phenotype with fewer estrous cycles, elevated plasma testosterone levels, reduced corpora lutea formation, and alterations in hypothalamic and ovarian gene expression. Thus, the phenotypes of the AKO mice were very different from those seen in the neuronal knockout mice, suggesting distinct roles for PPARγ in these two cell types.
Collapse
Affiliation(s)
- Marina O Fernandez
- Department of Medicine, School of Medicine, University of California San Diego, La Jolla, California 92093.,Laboratory of Neuroendocrinology, Instituto de Biología y Medicina Experimental, CONICET. Vuelta de Obligado 2490, C1428ADN, Buenos Aires, Argentina
| | - Katherine Hsueh
- Department of Medicine, School of Medicine, University of California San Diego, La Jolla, California 92093
| | - Hyun Tae Park
- Department of Medicine, School of Medicine, University of California San Diego, La Jolla, California 92093.,Department of Obstetrics and Gynecology, Korea University Anam Hospital, Seoul 136-705, Korea
| | - Consuelo Sauceda
- Department of Medicine, School of Medicine, University of California San Diego, La Jolla, California 92093
| | - Vicky Hwang
- Department of Medicine, School of Medicine, University of California San Diego, La Jolla, California 92093
| | - Deepak Kumar
- Department of Medicine, School of Medicine, University of California San Diego, La Jolla, California 92093
| | - Sun Kim
- Department of Medicine, School of Medicine, University of California San Diego, La Jolla, California 92093
| | - Emily Rickert
- Department of Medicine, School of Medicine, University of California San Diego, La Jolla, California 92093
| | - Sumana Mahata
- Department of Medicine, School of Medicine, University of California San Diego, La Jolla, California 92093
| | - Nicholas J G Webster
- Department of Medicine, School of Medicine, University of California San Diego, La Jolla, California 92093.,Medical Research Service, VA San Diego Healthcare System, San Diego, California 92161.,Moores Cancer Center, University of California San Diego, La Jolla, California 92093
| |
Collapse
|
11
|
Low KL, Ma C, Soma KK. Tyramide Signal Amplification Permits Immunohistochemical Analyses of Androgen Receptors in the Rat Prefrontal Cortex. J Histochem Cytochem 2017; 65:295-308. [PMID: 28438093 PMCID: PMC5407533 DOI: 10.1369/0022155417694870] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2016] [Accepted: 01/24/2017] [Indexed: 11/22/2022] Open
Abstract
Research on neural androgen receptors (ARs) has traditionally focused on brain regions that regulate reproductive and aggressive behaviors, such as the hypothalamus and amygdala. Although many cells in the prefrontal cortex (PFC) also express ARs, the number of ARs per cell appears to be much lower, and thus, AR immunostaining is often hard to detect and quantify in the PFC. Here, we demonstrate that biotin tyramide signal amplification (TSA) dramatically increases AR immunoreactivity in the rat brain, including critical regions of the PFC such as the medial PFC (mPFC) and orbitofrontal cortex (OFC). We show that TSA is useful for AR detection with both chromogenic and immunofluorescent immunohistochemistry. Double-labeling studies reveal that AR+ cells in the PFC and hippocampus are NeuN+ but not GFAP+ and thus primarily neuronal. Finally, in gonadally intact rats, more AR+ cells are present in the mPFC and OFC of males than of females. Future studies can use TSA to further examine AR immunoreactivity across ages, sexes, strains, and different procedures (e.g., fixation methods). In light of emerging evidence for the androgen regulation of executive function and working memory, these results may help understand the distribution and roles of ARs in the PFC.
Collapse
Affiliation(s)
- Katelyn L. Low
- Department of Psychology and The Djavad Mowafaghian Centre for Brain Health (KLL, CM, KKS), The University of British Columbia, Vancouver, British Columbia, Canada
- Department of Zoology (KLL, KKS), The University of British Columbia, Vancouver, British Columbia, Canada
| | - Chunqi Ma
- Department of Psychology and The Djavad Mowafaghian Centre for Brain Health (KLL, CM, KKS), The University of British Columbia, Vancouver, British Columbia, Canada
- Department of Zoology (KLL, KKS), The University of British Columbia, Vancouver, British Columbia, Canada
| | - Kiran K. Soma
- Kiran K. Soma, Department of Psychology, University of British Columbia, 2136 West Mall, Vancouver, British Columbia, Canada V6T 1Z4.E-mail:
| |
Collapse
|
12
|
Calisi RM, Geraghty AC, Avila A, Kaufer D, Bentley GE, Wingfield JC. Patterns of hypothalamic GnIH change over the reproductive period in starlings and rats. Gen Comp Endocrinol 2016; 237:140-146. [PMID: 27591072 DOI: 10.1016/j.ygcen.2016.08.015] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Revised: 08/05/2016] [Accepted: 08/24/2016] [Indexed: 11/30/2022]
Abstract
Gonadotropin inhibitory hormone (GnIH) exerts powerful inhibitory effects on various levels of the vertebrate hypothalamic-pituitary-gonadal (reproductive) axis, yet little is known of how it might change naturally over the course of reproduction. We characterized patterns of hypothalamic GnIH cell abundance over the reproductive period in two popular models used for the study of reproductive endocrinology: European starlings (Sturnus vulgaris) and Sprague-Dawley rats (Rattus norvegicus). We also examined the effects on an unpredictable change in the environment on GnIH cell abundance during the reproductive period, specifically during the period of parental care, by simulating a nest predation event and removing eggs/pups. In both species, we report changes in GnIH cell abundance are occurring at similar reproductive time points but are not always directionally parallel; this may be due to a difference in life histories and physiology mediating parental care. We discovered that cells immunoreactive for the GnIH peptide in male and female starlings are most highly abundant on the first day of incubation and the first day after the first chick hatches. Conversely in rats, GnIH cell abundance decreases in dams on the first day after pups are born. In both male and female starlings and female rats, GnIH cell abundance increases in response to egg/pup loss, indicating that GnIH responds to an unpredictable change in the environment in a potentially conserved fashion. These changes in GnIH cell abundance during the reproductive period inspire further investigation of its adaptive role in reproductive physiological events and behaviors, especially parental care.
Collapse
Affiliation(s)
- R M Calisi
- Department of Neurobiology, Physiology, and Behavior, University of California, Davis, CA, USA; Department of Integrative Biology, University of California, Berkeley, CA, USA.
| | - A C Geraghty
- Department of Integrative Biology, University of California, Berkeley, CA, USA
| | - A Avila
- Department of Integrative Biology, University of California, Berkeley, CA, USA
| | - D Kaufer
- Department of Integrative Biology, University of California, Berkeley, CA, USA; Helen Wills Neuroscience Institute, University of California, Berkeley, CA, USA
| | - G E Bentley
- Department of Integrative Biology, University of California, Berkeley, CA, USA; Helen Wills Neuroscience Institute, University of California, Berkeley, CA, USA
| | - J C Wingfield
- Department of Neurobiology, Physiology, and Behavior, University of California, Davis, CA, USA
| |
Collapse
|
13
|
Maggi R. Physiology of Gonadotropin-Releasing Hormone (Gnrh): Beyond the Control of Reproductive Functions. ACTA ACUST UNITED AC 2016. [DOI: 10.15406/mojap.2016.02.00063] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|