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Catalano-Iniesta L, Iglesias-Osma MC, Sánchez-Robledo V, Carretero-Hernández M, Blanco EJ, Carretero J, García-Barrado MJ. Variations in adrenal gland medulla and dopamine effects induced by the lack of Irs2. J Physiol Biochem 2018; 74:667-677. [PMID: 30367392 DOI: 10.1007/s13105-018-0655-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 10/18/2018] [Indexed: 01/26/2023]
Abstract
The adrenomedullary chromaffin cells' hormonal pathway has been related to the pathophysiology of diabetes mellitus. In mice, the deletion of insulin receptor substrate type 2 (Irs2) causes peripheral insulin resistance and reduction in β-cell mass, leading to overt diabetes, with gender differences on adrenergic signaling. To further unravel the relevance of Irs2 on glycemic control, we analyzed in adult Irs2 deficient (Irs2-/-) mice, of both sexes but still normoglycemic, dopamine effects on insulin secretion and glycerol release, as well as their adrenal medulla by an immunohistochemical and morphologic approach. In isolated islets, 10 μM dopamine significantly inhibited insulin release in wild-type (WT) and female Irs2-/- mice; however, male Irs2-/- islets were insensitive to that catecholamine. Similarly, on isolated adipocytes, gender differences were observed between WT and Irs2-/- mice in basal and evoked glycerol release with crescent concentrations of dopamine. By immunohistochemistry, reactivity to tyrosine hydroxylase (TH) in female mice was significantly higher in the adrenal medulla of Irs2-/- compared to WT; although no differences for TH-immunopositivity were observed between the male groups of mice. However, compared to their corresponding WT animals, adrenomedullary chromaffin cells of Irs2-/- mice showed a significant decrease in the cellular and nuclear areas, and even in their percentage of apoptosis. Therefore, our observations suggest that, together with gender differences on dopamine responses in Irs2-/- mice, disturbances in adrenomedullary chromaffin cells could be related to deficiency of Irs2. Accordingly, Irs2 could be necessary for adequate glucose homeostasis and maintenance of the population of the adrenomedullary chromaffin cells.
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Affiliation(s)
- Leonardo Catalano-Iniesta
- Department of Physiology and Pharmacology, INCyL and IBSAL, Faculty of Medicine, University of Salamanca, Avda. Alfonso X el Sabio, s/n, E-37007, Salamanca, Spain.,Laboratory of Neuroendocrinology, Institute of Neurosciences of Castilla y León (INCyL), University of Salamanca, Salamanca, Spain.,Laboratory of Neuroendocrinology and Obesity, Institute of Biomedical Research of Salamanca (IBSAL), University of Salamanca, Salamanca, Spain
| | - María Carmen Iglesias-Osma
- Department of Physiology and Pharmacology, INCyL and IBSAL, Faculty of Medicine, University of Salamanca, Avda. Alfonso X el Sabio, s/n, E-37007, Salamanca, Spain.,Laboratory of Neuroendocrinology, Institute of Neurosciences of Castilla y León (INCyL), University of Salamanca, Salamanca, Spain.,Laboratory of Neuroendocrinology and Obesity, Institute of Biomedical Research of Salamanca (IBSAL), University of Salamanca, Salamanca, Spain
| | - Virginia Sánchez-Robledo
- Department of Physiology and Pharmacology, INCyL and IBSAL, Faculty of Medicine, University of Salamanca, Avda. Alfonso X el Sabio, s/n, E-37007, Salamanca, Spain.,Laboratory of Neuroendocrinology, Institute of Neurosciences of Castilla y León (INCyL), University of Salamanca, Salamanca, Spain.,Laboratory of Neuroendocrinology and Obesity, Institute of Biomedical Research of Salamanca (IBSAL), University of Salamanca, Salamanca, Spain
| | - Marta Carretero-Hernández
- Laboratory of Neuroendocrinology, Institute of Neurosciences of Castilla y León (INCyL), University of Salamanca, Salamanca, Spain.,Laboratory of Neuroendocrinology and Obesity, Institute of Biomedical Research of Salamanca (IBSAL), University of Salamanca, Salamanca, Spain.,Department of Human Anatomy and Histology, Faculty of Medicine, University of Salamanca, Salamanca, Spain
| | - Enrique J Blanco
- Laboratory of Neuroendocrinology, Institute of Neurosciences of Castilla y León (INCyL), University of Salamanca, Salamanca, Spain.,Laboratory of Neuroendocrinology and Obesity, Institute of Biomedical Research of Salamanca (IBSAL), University of Salamanca, Salamanca, Spain.,Department of Human Anatomy and Histology, Faculty of Medicine, University of Salamanca, Salamanca, Spain
| | - José Carretero
- Laboratory of Neuroendocrinology, Institute of Neurosciences of Castilla y León (INCyL), University of Salamanca, Salamanca, Spain.,Laboratory of Neuroendocrinology and Obesity, Institute of Biomedical Research of Salamanca (IBSAL), University of Salamanca, Salamanca, Spain.,Department of Human Anatomy and Histology, Faculty of Medicine, University of Salamanca, Salamanca, Spain
| | - María José García-Barrado
- Department of Physiology and Pharmacology, INCyL and IBSAL, Faculty of Medicine, University of Salamanca, Avda. Alfonso X el Sabio, s/n, E-37007, Salamanca, Spain. .,Laboratory of Neuroendocrinology, Institute of Neurosciences of Castilla y León (INCyL), University of Salamanca, Salamanca, Spain. .,Laboratory of Neuroendocrinology and Obesity, Institute of Biomedical Research of Salamanca (IBSAL), University of Salamanca, Salamanca, Spain.
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Relation among Aromatase P450 and Tumoral Growth in Human Prolactinomas. Int J Mol Sci 2017; 18:ijms18112299. [PMID: 29104246 PMCID: PMC5713269 DOI: 10.3390/ijms18112299] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 10/25/2017] [Accepted: 10/27/2017] [Indexed: 02/01/2023] Open
Abstract
The pituitary gland is part of hypothalamic-pituitary–gonadal axis, which controls development, reproduction, and aging in humans and animals. In addition, the pituitary gland is regulated mainly by hormones and neurotransmitters released from the hypothalamus and by systemic hormones secreted by target glands. Aromatase P450, the enzyme responsible for the catabolization of aromatizable androgens to estrogens, is expressed in different parts of body, including the pituitary gland. Moreover, aromatase P450 is involved in sexual dimorphism where alteration in the level of aromatase can initiate a number of diseases in both genders. On the other hand, the direct actions of estrogens, mainly estradiol, are well known for stimulating prolactin release. Numerous studies have shown that changes in the levels of estrogens, among other factors, have been implicated in the genesis and development of prolactinoma. The pituitary gland can produce estradiol locally in several types of endocrine cells, and it is possible that aromatase could be responsible for the maintenance of the population of lactotroph cells and the modulation of the action of central or peripheral regulators. Aromatase overexpression due to inappropriate gene regulation has clinical effects such as the pathogenesis of prolactinomas. The present study reports on the synthesis of pituitary aromatase, its regulation by gonadal steroids, and the physiological roles of aromatase on pituitary endocrine cells. The involvement of aromatase in the pathogenesis of pituitary tumors, mainly prolactinomas, through the auto-paracrine production of estradiol is reviewed.
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