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Ramos L. Dimorphic frataxin and its gene regulation by sex steroids in hamsters. Mol Genet Genomics 2023; 298:615-626. [PMID: 36929169 DOI: 10.1007/s00438-023-02004-6] [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: 11/15/2022] [Accepted: 03/03/2023] [Indexed: 03/18/2023]
Abstract
The role of frataxin (FXN) has been studied extensively in Friedreich ataxia patients, however, the molecular bases underlining the sex steroid-dependent gene expression profiles of FXN in adult tissues are unknown. I describe the molecular characterization of hamster FXN by examining the sexually dimorphic expression and its regulation by sex steroids. Sequence analysis of FXN cDNA showed 630 bp-long ORF encoding 209 amino acids. qPCR analysis revealed that FXN is detected in a wide range of tissues, with the highest expression in the heart, liver, and epididymis, and the weakest expression in the lung, spleen, uterus, and gut. In the male Harderian gland (HG), castration decreased FXN expression, while dihydrotestosterone (DHT) administration reestablished levels. FXN expression levels were higher in the male HG than the female HG. Expression levels in endocrine tissues showed a certain degree of sexual dimorphism; the transcript in the testis was significantly higher than those in the ovary. The effects of the estrous cycle on FXN expression remained unchanged in the HG, ovary, and adrenal glands; however, in the pancreas, the FXN mRNA was overexpressed during proestrus and exhibited sexual dimorphism as compared to the male pancreas. The mRNA expression results indicated that Harderian FXN may play a dynamic role in intracellular Fe of heme required for processing cytochromes and other hemeproteins, also suggesting that the moderate sexual dimorphism present in the HG and gonads could be regulated by androgens, while sexually dimorphic expression of FXN in the female pancreas may be controlled by sex steroids.
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Affiliation(s)
- L Ramos
- Department of Reproductive Biology, Instituto Nacional de Ciencias Médicas y Nutrición, Salvador Zubirán, Av. Vasco de Quiroga #15, Tlalpan, C.P. 14080, México City, México.
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Ramos L, Mares L. Hamster DAX1: Molecular insights, specific expression, and its role in the Harderian gland. Comp Biochem Physiol A Mol Integr Physiol 2021; 263:111096. [PMID: 34653610 DOI: 10.1016/j.cbpa.2021.111096] [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: 08/20/2021] [Revised: 10/08/2021] [Accepted: 10/08/2021] [Indexed: 10/20/2022]
Abstract
DAX1 plays an essential role in the differentiation and physiology of the Hypothalamic-Pituitary-Adrenal-Gonadal (HPAG) axis during embryogenesis. However, in adult tissues, in addition to the HPAG axis, evidence has not been found for its differential expression and function. We isolated the DAX1 cDNA to analyze its tissue localization and gene expression profiles in male and female hamsters' Harderian glands (HGs), Mesocricetus auratus. The isolated cDNA clone contains 1848 base pairs (bp), and a 1428-bp open reading frame (ORF) encodes a 476 amino acid protein. Sequence alignments and the phylogenetic tree display a relevant percentage of similarity with human (66%), rat (81%), and mouse (84%) sequences. In adult tissues, the mRNA distribution demonstrated that DAX1 is present in testis, ovaries, and male and female HGs. The highest expression profiles were identified in the adrenal glands, where females exhibit higher mRNA levels than males. The sexually dimorphic expression of DAX1 in adrenals suggests that its presence could be associated with regulating, functioning, and maintaining this endocrine tissue. These findings indicate that the DAX1 gene is limitedly expressed in adult tissues. In the HGs, we demonstrate the absence of sexually dimorphic gene expression. Our results suggest that DAX1 might have an additional physiological function outside of the HPAG axis, specifically in the HG, which may be required for the regulation of intracrine steroidogenesis, secretion, and maintenance of exocrine tissue.
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Affiliation(s)
- L Ramos
- Department of Reproductive Biology, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, México City, Mexico.
| | - L Mares
- Department of Reproductive Biology, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, México City, Mexico
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Lin YC, Papadopoulos V. Neurosteroidogenic enzymes: CYP11A1 in the central nervous system. Front Neuroendocrinol 2021; 62:100925. [PMID: 34015388 DOI: 10.1016/j.yfrne.2021.100925] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 05/07/2021] [Accepted: 05/14/2021] [Indexed: 01/08/2023]
Abstract
Neurosteroids, steroid hormones synthesized locally in the nervous system, have important neuromodulatory and neuroprotective effects in the central nervous system. Progress in neurosteroid research has led to the successful translation of allopregnanolone into an approved therapy for postpartum depression. However, there is insufficient evidence to support the assumption that steroidogenesis is exactly the same between the nervous system and the periphery. This review focuses on CYP11A1, the only enzyme currently known to catalyze the first reaction in steroidogenesis to produce pregnenolone, the precursor to all other steroids. Although CYP11A1 mRNA has been found in brain of many mammals, the presence of CYP11A1 protein has been difficult to detect, particularly in humans. Here, we highlight the discrepancies in the current evidence for CYP11A1 in the central nervous system and propose new directions for understanding neurosteroidogenesis, which will be crucial for developing neurosteroid-based therapies for the future.
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Affiliation(s)
- Yiqi Christina Lin
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States
| | - Vassilios Papadopoulos
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, United States.
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Santillo A, Chieffi Baccari G, Minucci S, Falvo S, Venditti M, Di Matteo L. The Harderian gland: Endocrine function and hormonal control. Gen Comp Endocrinol 2020; 297:113548. [PMID: 32679156 DOI: 10.1016/j.ygcen.2020.113548] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 06/30/2020] [Accepted: 07/09/2020] [Indexed: 01/17/2023]
Abstract
The Harderian gland (HG) is an exocrine gland located within the eye socket in a variety of tetrapods. During the 1980s and 1990s the HG elicited great interest in the scientific community due to its morphological and functional complexity, and from a phylogenetic point of view. A comparative approach has contributed to a better understanding of its physiology. Whereas the chemical nature of its secretions (mucous, serous or lipids) varies between different groups of tetrapods, the lipids represent the more common component among different species. Indeed, besides being an accessory to lubricate the nictitating membrane, the lipids may have a pheromonal function. Porphyrins and melatonin secretion is a feature of the rodent HG. The porphyrins, being phototransducers, could modulate HG melatonin production. The melatonin synthesis suggests an involvement of the HG in the retinal-pineal axis. Finally, StAR protein and steroidogenic enzyme activities in the rat HG suggests that the gland contributes to steroid hormone synthesis. Over the past twenty years, much has become known on the hamster (Mesocricetus auratus) HG, unique among rodents in displaying a remarkable sexual dimorphism concerning the contents of porphyrins and melatonin. Mainly for this reason, the hamster HG has been used as a model to compare, under normal conditions, the physiological oxidative stress between females (strong) and males (moderate). Androgens are responsible for the sexual dimorphism in hamster and they are known to control the HG secretory activity in different species. Furthermore, HG is a target of pituitary, pineal and thyroid hormones. This review offers a comparative panorama of the endocrine activity of the HG as well as the hormonal control of its secretory activity, with a particular emphasis on the sex dimorphic aspects of the hamster HG.
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Affiliation(s)
- Alessandra Santillo
- Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Università degli Studi della Campania 'Luigi Vanvitelli', Via Vivaldi, 43-81100 Caserta, Italy.
| | - Gabriella Chieffi Baccari
- Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Università degli Studi della Campania 'Luigi Vanvitelli', Via Vivaldi, 43-81100 Caserta, Italy
| | - Sergio Minucci
- Dipartimento di Medicina Sperimentale, Sez. Fisiologia Umana e Funzioni Biologiche Integrate, Università degli Studi della Campania 'Luigi Vanvitelli', via Santa Maria di Costantinopoli, 16-80138 Napoli, Italy
| | - Sara Falvo
- Dipartimento di Scienze e Tecnologie Ambientali, Biologiche e Farmaceutiche, Università degli Studi della Campania 'Luigi Vanvitelli', Via Vivaldi, 43-81100 Caserta, Italy
| | - Massimo Venditti
- Dipartimento di Medicina Sperimentale, Sez. Fisiologia Umana e Funzioni Biologiche Integrate, Università degli Studi della Campania 'Luigi Vanvitelli', via Santa Maria di Costantinopoli, 16-80138 Napoli, Italy
| | - Loredana Di Matteo
- Dipartimento di Medicina Sperimentale, Sez. Fisiologia Umana e Funzioni Biologiche Integrate, Università degli Studi della Campania 'Luigi Vanvitelli', via Santa Maria di Costantinopoli, 16-80138 Napoli, Italy
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Efimova VS, Isaeva LV, Labudina AA, Tashlitsky VN, Rubtsov MA, Novikova LA. Polycistronic expression of the mitochondrial steroidogenic P450scc system in the HEK293T cell line. J Cell Biochem 2018; 120:3124-3136. [DOI: 10.1002/jcb.27577] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2018] [Accepted: 08/08/2018] [Indexed: 12/18/2022]
Affiliation(s)
- Vera S. Efimova
- Department of Molecular Biology Faculty of Biology, M.V. Lomonosov Moscow State University Moscow Russia
- LIA LFR2O (LIA French‐Russian Cancer Research Laboratory) Villejuif France – Moscow Russia
| | - Ludmila V. Isaeva
- Department of Molecular Basis on Ontogenesis A.N. Belozersky Institute of Physico‐Chemical Biology, M.V. Lomonosov Moscow State University Moscow Russia
| | - Anastasia A. Labudina
- Department of Molecular Biology Faculty of Biology, M.V. Lomonosov Moscow State University Moscow Russia
| | - Vadim N. Tashlitsky
- Division of Chemistry of Natural Compounds Faculty of Chemistry, M.V. Lomonosov Moscow State University Moscow Russia
| | - Mikhail A. Rubtsov
- Department of Molecular Biology Faculty of Biology, M.V. Lomonosov Moscow State University Moscow Russia
- LIA LFR2O (LIA French‐Russian Cancer Research Laboratory) Villejuif France – Moscow Russia
- Department of Biochemistry I.M. Sechenov First Moscow State Medical University (Sechenov University) 119991 Moscow Russia
- Institute of Translational Medicine and Biotechnology I.M. Sechenov First Moscow State Medical University (Sechenov University) Moscow Russia
| | - Ludmila A. Novikova
- Department of Molecular Basis on Ontogenesis A.N. Belozersky Institute of Physico‐Chemical Biology, M.V. Lomonosov Moscow State University Moscow Russia
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Falvo S, Chieffi Baccaria G, Spaziano G, Rosati L, Venditti M, Di Fiore MM, Santillo A. StAR protein and steroidogenic enzyme expressions in the rat Harderian gland. C R Biol 2018. [PMID: 29534958 DOI: 10.1016/j.crvi.2018.02.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The Harderian gland (HG) of the rat (Rattus norvegicus) secretes copious amounts of lipids, such as cholesterol. Here we report a study of the expressions of the StAR protein and key steroidogenic enzymes in the HG of male and female rats. The objective of the present investigation was to ascertain (a) whether the rat HG is involved in steroid production starting with cholesterol, and (b) whether the pattern of gene and protein expressions together with the enzymatic activities display sexual dimorphism. The results demonstrate, for the first time, the expression of StAR gene and protein, and Cyp11a1, Hsd3b1, Hsd17b3, Srd5a1, Srd5a2 and Cyp19a1 genes in the rat HG. StAR mRNA and protein expressions were much greater in males than in females. Immunohistochemical analysis demonstrated a non-homogeneous StAR distribution among glandular cells. Hsd17b3 and Cyp19a1 mRNA levels were higher in males than in females, whereas Srd5a1 mRNA levels were higher in females than in males. No significant differences were observed in mRNA levels of Cyp11a1, Hsd3b1 and Srd5a2 between sexes. Furthermore, the in vitro experiments demonstrated a higher 5α-reductase activity in the female as compared to the male HG vice versa a higher P450 aro activity in males as compared to females. These results suggest that the Harderian gland can be classified as a steroidogenic tissue because it synthesizes cholesterol, expresses StAR and steroidogenic enzymes involved in both androgen and estrogen synthesis. The dimorphic expression and activity of the steroidogenic enzymes may suggest sex-specific hormonal effects into the HG physiology.
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Affiliation(s)
- Sara Falvo
- Department of Environmental, Biological, and Pharmaceutical Sciences & Technologies, University of Campania "L. Vanvitelli", Caserta, Italy
| | - Gabriella Chieffi Baccaria
- Department of Environmental, Biological, and Pharmaceutical Sciences & Technologies, University of Campania "L. Vanvitelli", Caserta, Italy
| | - Giuseppe Spaziano
- Department of Experimental Medicine, School of Medicine, University of Campania "L. Vanvitelli", Napoli, Italy
| | - Luigi Rosati
- Department of Biology, Federico II Naples University, Napoli, Italy
| | - Massimo Venditti
- Department of Experimental Medicine, School of Medicine, University of Campania "L. Vanvitelli", Napoli, Italy
| | - Maria Maddalena Di Fiore
- Department of Environmental, Biological, and Pharmaceutical Sciences & Technologies, University of Campania "L. Vanvitelli", Caserta, Italy
| | - Alessandra Santillo
- Department of Environmental, Biological, and Pharmaceutical Sciences & Technologies, University of Campania "L. Vanvitelli", Caserta, Italy.
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Xu Q, Song Y, Chen Y, Liu R, Zhang Y, Li Y, Huang Z, Zhao W, Chang G, Chen G. Molecular cloning and expression patterns of the cholesterol side chain cleavage enzyme (CYP11A1) gene during the reproductive cycle in goose (Anas cygnoides). J Anim Sci Biotechnol 2015; 6:54. [PMID: 26702355 PMCID: PMC4688999 DOI: 10.1186/s40104-015-0053-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 12/01/2015] [Indexed: 11/18/2022] Open
Abstract
Background CYP11A1, a gene belonging to the family 11 of cytochrome P450, encodes a crucial steroidogenic enzyme that catalyzes the initial step in the production of all classes of steroids. Many studies show that CYP11A1 plays a role in ovary function. However, the role of CYP11A1 in goose reproductive cycle remains largely unknown. Results In this study, full-length CYP11A1 cDNA of Zhedong goose was obtained using reverse transcription polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE). The cDNA consisted of a 96-base pair (bp) 5′untranslated region (UTR), a 179-bp 3′UTR and a 1509-bp open reading frame. The open reading frame encodes a putative 503 amino acid protein that shares high homology with CYP11A1 of other birds. The amino acid sequence possesses conserved domains of the P450 superfamily, which include the steroid-binding domain and the heme-binding region. Real-time quantitative polymerase chain reaction (qPCR) analysis revealed CYP11A1 mRNA was expressed ubiquitously in every Zhedong goose tissue analyzed, including the heart, liver, glandular stomach, lung, spleen, kidney, intestinum tenue, intestinum crassum, cerebrum, cerebellum, muscle, oviduct, pituitary, hypothalamus and ovary.. The relatively low levels of CYP11A1 mRNA were detected in pituitary, ovary and oviduct tissues at ovulation when compared with levels at oviposition. Interestingly, higher expression was observed in ovary and oviduct tissues during brooding. Lastly, higher mRNA expression of Yangzhou geese was detected during the ovulation period than that of Zhedong geese. Conclusions Our findings reveal the sequence characterization and expression patterns of the CYP11A1 gene during the goose reproductive cycle, which may provides correlative evidence that CYP11A1 expression is important in reproduction activity.
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Affiliation(s)
- Qi Xu
- Key Laboratory of Animal Genetics and Breeding and Molecular Design of Jiangsu Province, Yangzhou University, Yangzhou, 225009 PR China
| | - Yadong Song
- Key Laboratory of Animal Genetics and Breeding and Molecular Design of Jiangsu Province, Yangzhou University, Yangzhou, 225009 PR China
| | - Yang Chen
- Key Laboratory of Animal Genetics and Breeding and Molecular Design of Jiangsu Province, Yangzhou University, Yangzhou, 225009 PR China
| | - Ran Liu
- Key Laboratory of Animal Genetics and Breeding and Molecular Design of Jiangsu Province, Yangzhou University, Yangzhou, 225009 PR China
| | - Yang Zhang
- Key Laboratory of Animal Genetics and Breeding and Molecular Design of Jiangsu Province, Yangzhou University, Yangzhou, 225009 PR China
| | - Yang Li
- Key Laboratory of Animal Genetics and Breeding and Molecular Design of Jiangsu Province, Yangzhou University, Yangzhou, 225009 PR China
| | - Zhengyang Huang
- Key Laboratory of Animal Genetics and Breeding and Molecular Design of Jiangsu Province, Yangzhou University, Yangzhou, 225009 PR China
| | - Wenming Zhao
- Key Laboratory of Animal Genetics and Breeding and Molecular Design of Jiangsu Province, Yangzhou University, Yangzhou, 225009 PR China
| | - Guobin Chang
- Key Laboratory of Animal Genetics and Breeding and Molecular Design of Jiangsu Province, Yangzhou University, Yangzhou, 225009 PR China
| | - Guohong Chen
- Key Laboratory of Animal Genetics and Breeding and Molecular Design of Jiangsu Province, Yangzhou University, Yangzhou, 225009 PR China
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Slominski AT, Li W, Kim TK, Semak I, Wang J, Zjawiony JK, Tuckey RC. Novel activities of CYP11A1 and their potential physiological significance. J Steroid Biochem Mol Biol 2015; 151:25-37. [PMID: 25448732 PMCID: PMC4757911 DOI: 10.1016/j.jsbmb.2014.11.010] [Citation(s) in RCA: 217] [Impact Index Per Article: 24.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Revised: 10/31/2014] [Accepted: 11/10/2014] [Indexed: 01/08/2023]
Abstract
CYP11A1, found only in vertebrates, catalyzes the first step of steroidogenesis where cholesterol is converted to pregnenolone. The purified enzyme, also converts desmosterol and plant sterols including campesterol and β-sitosterol, to pregnenolone. Studies, initially with purified enzyme, reveal that 7-dehydrocholesterol (7DHC), ergosterol, lumisterol 3, and vitamins D3 and D2 also serve as substrates for CYP11A1, with 7DHC being better and vitamins D3 and D2 being poorer substrates than cholesterol. Adrenal glands, placenta, and epidermal keratinocytes can also carry out these conversions and 7-dehydropregnenolone has been detected in the epidermis, adrenal glands, and serum, and 20-hydroxyvitamin D3 was detected in human serum and the epidermis. Thus, this metabolism does appear to occur in vivo, although its quantitative importance and physiological role remain to be established. CYP11A1 action on 7DHC in vivo is further supported by detection of Δ(7)steroids in Smith-Lemli-Opitz syndrome patients. The activity of CYP11A1 is affected by the structure of the substrate with sterols having steroidal or Δ(7)-steroidal structures undergoing side chain cleavage following hydroxylations at C22 and C20. In contrast, metabolism of vitamin D involves sequential hydroxylations that start at C20 but do not lead to cleavage. Molecular modeling using the crystal structure of CYP11A1 predicts that other intermediates of cholesterol synthesis could also serve as substrates for CYP11A1. Finally, CYP11A1-derived secosteroidal hydroxy-derivatives and Δ(7)steroids are biologically active when administered in vitro in a manner dependent on the structure of the compound and the lineage of the target cells, suggesting physiological roles for these metabolites. This article is part of a special issue entitled 'SI: Steroid/Sterol signaling'.
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Affiliation(s)
- Andrzej T Slominski
- Department of Pathology and Laboratory Medicine, University of Tennessee HSC, Memphis, TN, USA; Division of Rheumatology of the Department of Medicine, University of Tennessee HSC, Memphis, TN, USA.
| | - Wei Li
- Department of Pharmaceutical Sciences, University of Tennessee HSC, Memphis, TN, USA
| | - Tae-Kang Kim
- Department of Pathology and Laboratory Medicine, University of Tennessee HSC, Memphis, TN, USA
| | - Igor Semak
- Department of Biochemistry, Belarusian State University, Minsk, Belarus
| | - Jin Wang
- Department of Pharmaceutical Sciences, University of Tennessee HSC, Memphis, TN, USA
| | - Jordan K Zjawiony
- Department of BioMolecular Sciences and Research Institute of Pharmaceutical Sciences, School of Pharmacy, University of Mississippi, University, MS 38677-1848, USA
| | - Robert C Tuckey
- School of Chemistry and Biochemistry, The University of Western Australia, Crawley, WA, Australia.
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Saadi-Brenkia O, Haniche N, Bendjelloul M. Light and electron microscopic studies of the Gerbillus tarabuli (Thomas, 1902) Harderian gland. Zoolog Sci 2013; 30:53-9. [PMID: 23317366 DOI: 10.2108/zsj.30.53] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The purpose of this investigation was to study the morphological aspects of the Harderian gland in Gerbillus tarabuli. Tissues were obtained from both male and female adult Gerbillus tarabuli and processed for light and electron microscopy. The Harderian gland in gerbil is large and well developed, covered by a thin capsule, from which thin septae extend, subdividing the gland into lobes and lobules. The endpieces of the gland are tubuloalveolar, which produce a secretion of lipid character. The glandular epithelium is pseudostratified with two types of secretory cells, the type C cells are columnar in shape with large lipid vacuoles, and type P cells pyramidal and serous, they are basally located with no luminal aspect. The epithelium possesses well-developed myoepithelial cells. The wide lumina are filled with lipid vacuoles, cellular debris, and porphyrins. The Harderian gland of the gerbil has no morphologically distinct duct system; a single extraglandular excretory duct is detected. Electron microscopic examination revealed that type C cells contain large electron-light lipid vacuoles, a well and extensive reticulum endoplasmic and a large number of mitochondria. The pyramidal cells are characterized by a small number of PAS-positive granules at the basal region; these cells exhibit one or two round nuclei, many electron-dense granules, crystalloid bodies, abundant mitochondria and many ribosomes in their cytoplasm. The three mechanism of secretion are seen in the Harderian gland of Gerbillus tarabuli. In its overall characteristics, the Harderian gland of Gerbillus tarabuli conforms to the general pattern observed in rodents. However, further research will be needed to correlate the presence of cytoplasmic slashes, crystalloids bodies and glycoproteins in epithelial cells with the biology of these animals and to their functional significance.
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Affiliation(s)
- Ouanassa Saadi-Brenkia
- Department of Biology, University of Boumerdes Faculty of Sciences, Avenue de l'indépendance, 35000 Boumerdes, Algeria.
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Miyashita T, Okubo M, Shinomiya T, Nakagawa KI, Kawaguchi M. Pregnenolone Biosynthesis in the Rat Salivary Gland and Its Inhibitory Effect on Secretion. J Pharmacol Sci 2011; 115:56-62. [DOI: 10.1254/jphs.10267fp] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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Okano S, Zhou L, Kusaka T, Shibata K, Shimizu K, Gao X, Kikuchi Y, Togashi Y, Hosoya T, Takahashi S, Nakajima O, Yamamoto M. Indispensable function for embryogenesis, expression and regulation of the nonspecific form of the 5-aminolevulinate synthase gene in mouse. Genes Cells 2009; 15:77-89. [PMID: 20015225 DOI: 10.1111/j.1365-2443.2009.01366.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The first step of heme biosynthesis in animals is catalyzed by 5-aminolevulinate synthase (ALAS), which controls heme supply in various tissues. To clarify the roles that the nonspecific isoform of ALAS (ALAS-N) plays in vivo, we prepared a green fluorescent protein (GFP) knock-in mouse line in which the Alas1 gene (encoding ALAS-N) is replaced with a gfp gene. We found that mice bearing a homozygous knock-in allele (Alas1(GFP/GFP)) were lethal by embryonic day 8.5, demonstrating that ALAS-N is essential for early embryogenesis. Fluorescence microscopic and flow cytometric analyses of heterozygous mouse (Alas1(+/GFP)) tissues showed that the Alas1 expression level differs substantially in tissues; Alas1 is highly expressed in testis Leydig cells, exocrine glands (including submandibular and parotid glands), endocrine glands (such as adrenal and thyroid glands) and hematopoietic lineage cells (including neutrophils and eosinophils). Quantitative analyses of GFP mRNA and ALAS-N mRNA in various tissues of Alas1(+/GFP) mice suggested that the destabilization of ALAS-N mRNA was not uniform in the various tissues. These results thus lay bare that elaborate control of the endogenous heme supply operates in various mouse tissues through regulation of the ALAS-N expression level and that this control is essential for heme homeostasis in animals.
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Affiliation(s)
- Satoshi Okano
- Research Laboratory for Molecular Genetics, Yamagata University, Yamagata 990-9585, Japan
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Chávez B, Ramos L, Merchant-Larios H, Vilchis F. Cloning and expression of the estrogen receptor-alpha (Esr1) from the Harderian gland of the sea turtle (Lepidochelys olivacea). Gen Comp Endocrinol 2009; 162:203-9. [PMID: 19272391 DOI: 10.1016/j.ygcen.2009.02.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2008] [Revised: 02/18/2009] [Accepted: 02/23/2009] [Indexed: 10/21/2022]
Abstract
The effects of estradiol on the Harderian gland (HG) are believed to be partially regulated by the transcriptional regulation of the estrogen-related genes via estrogen receptor (ER). In reptiles, however, it has not been well established whether the HG contains or expresses steroid nuclear receptors. As a first step toward investigating the molecular mechanisms of estrogen signalling in the HG, we isolated the cDNA for ERalpha in the sea turtle Lepidochelys olivacea. ERalpha was cloned using RT-PCR coupled with 5' and 3' RACE procedures. The cDNA contains a complete open reading frame encoding 588 amino acid residues. Comparative analysis of this amino acid sequence showed moderate to strong conservation of the ERalpha (Esr1) gene within divergent vertebrate groups. In transfection studies, the cloned ER displayed high affinity K(d)=0.25nM and high specificity for 17beta-estradiol. Binding assays using sucrose density gradients demonstrated a specific 7-7.5 S binding component in the HG cytosolic fractions. RT-qPCR analysis showed significant ERalpha mRNA expression in the liver, HG, lung and brain. Altogether, these results provide evidence for the expression of intracellular ERs in the HG of the sea turtle and suggest that ERalpha may be an important modulator of the estrogen-mediated response in the HG of reptiles.
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Affiliation(s)
- Bertha Chávez
- Department of Reproductive Biology, Instituto Nacional de Ciencias Médicas y Nutrición S.Z., México D.F., Mexico
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Endo D, Kanaho YI, Park MK. Expression of sex steroid hormone-related genes in the embryo of the leopard gecko. Gen Comp Endocrinol 2008; 155:70-8. [PMID: 17543964 DOI: 10.1016/j.ygcen.2007.04.010] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2006] [Revised: 04/04/2007] [Accepted: 04/09/2007] [Indexed: 11/29/2022]
Abstract
Sex steroid hormones are known to play a central role in vertebrate sex determination and differentiation. However, the tissues in which they are produced or received during development, especially around the period of sex determination of the gonads, have rarely been investigated. In this study, we identified the cDNA sequence, including the full-length of the coding region of cholesterol side-chain cleavage enzyme (P450scc), from the leopard gecko; a lizard with temperature-dependent sex determination. Embryonic expression analysis of two steroidogenic enzymes, P450scc and P450 aromatase (P450arom), and four sex steroid hormone receptors, androgen receptor, estrogen receptor alpha and beta, and progesterone receptor, was subsequently conducted. mRNA expression of both steroidogenic enzymes was observed in the brain and gonads prior to the temperature-sensitive period of sex determination. The mRNAs of the four sex steroid hormone receptors were also detected in the brain and gonads at all stages examined. These results suggest the existence of a gonad-independent sex steroid hormone signaling system in the developing leopard gecko brain.
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Affiliation(s)
- Daisuke Endo
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-0033, Japan
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Storbeck KH, Swart P, Graham S, Swart AC. Evidence for the functional role of residues in the B'-C loop of baboon cytochrome P450 side-chain cleavage (CYP11A1) obtained by site-directed mutagenesis, kinetic analysis and homology modelling. J Steroid Biochem Mol Biol 2007; 103:65-75. [PMID: 17081746 DOI: 10.1016/j.jsbmb.2006.07.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2006] [Accepted: 07/12/2006] [Indexed: 10/24/2022]
Abstract
To gain further insight into the structure/function relationship of cytochrome P450 side-chain cleavage (CYP11A1), this enzyme was investigated in the Cape baboon (Papio ursinus). Four constructs were cloned and characterised in non-steroidogenic mammalian COS-1 cells. Wild type recombinant baboon CYP11A1 cDNA yielded a K(m) value of 1.6 microM for 25-hydroxycholesterol. The single amino acid substitutions, I98Q and I98K resulted in a 1.7- and 2.8-fold increases in K(m) values, respectively. Conversely, the introduction of the mutation, K103A, resulted in a 1.8-fold decrease in K(m). A homology model of CYP11A1, based on the crystal structures of CYP102 and CYP2C5, revealed that residues 98 and 103 lie within the B'-C loop and contribute to the spatial orientation and structural integrity of this domain. Based on these results we propose a topological model of the CYP11A1 active pocket, which is supported by substrate docking analysis and kinetic studies.
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Affiliation(s)
- Karl-Heinz Storbeck
- Department of Biochemistry, University of Stellenbosch, Stellenbosch 7602, South Africa
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15
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London SE, Monks DA, Wade J, Schlinger BA. Widespread capacity for steroid synthesis in the avian brain and song system. Endocrinology 2006; 147:5975-87. [PMID: 16935847 PMCID: PMC2903432 DOI: 10.1210/en.2006-0154] [Citation(s) in RCA: 106] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Steroids exert powerful effects on the brains and behavior of many species, but measures and manipulations of endocrine physiology in songbirds often reveal unexplained connections between steroids and the brain. The zebra finch song system, a sensorimotor neural circuit sensitive to steroids throughout life, organizes and functions largely in apparent independence from gonadally derived steroids. We tested the hypothesis that the zebra finch brain has the capacity for de novo steroidogenesis and that neurally synthesized steroids, neurosteroids, may impact the song system. Using multiple techniques, we demonstrate that the steroidogenic acute regulatory protein (StAR), cytochrome P450 side-chain cleavage (CYP11A1), and 3beta-hydroxysteroid dehydrogenase/Delta5-Delta4 isomerase, the first three factors in the steroidogenic pathway, are expressed in both developing and adult zebra finch brain. Detailed expression mapping at posthatch d 20 (P20) and adult reveals widespread area-specific expression and coexpression patterns for steroidogenic acute regulatory protein, CYP11A1, and 3beta-hydroxysteroid dehydrogenase/Delta5-Delta4 isomerase, which suggest neurosteroids may modulate multiple brain functions, including sensory and motor systems. Notably, whereas expression of other steroidogenic genes such as aromatase has been essentially absent from the song system, each of the major song nuclei express at least a subset of steroidogenic genes described here, establishing the song system as a potential steroidogenic circuit.
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Affiliation(s)
- Sarah E London
- University of California, Los Angeles, 621 Charles Young Drive South, P.O. Box 951606, Los Angeles, California 90095-1606, USA.
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Kazeto Y, Ijiri S, Adachi S, Yamauchi K. Cloning and characterization of a cDNA encoding cholesterol side-chain cleavage cytochrome P450 (CYP11A1): tissue-distribution and changes in the transcript abundance in ovarian tissue of Japanese eel, Anguilla japonica, during artificially induced sexual development. J Steroid Biochem Mol Biol 2006; 99:121-8. [PMID: 16616842 DOI: 10.1016/j.jsbmb.2005.12.004] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2005] [Accepted: 12/19/2005] [Indexed: 10/24/2022]
Abstract
Cholesterol side-chain cleavage cytochrome P450 (CYP11A1: P450scc) is a crucial steroidogenic enzyme that catalyzes an initial step in the production of all classes of steroids. A cDNA encoding Japanese eel P450scc was cloned and characterized. The cDNA putatively encoded 521 amino acid residues with high homology to those of other vertebrate forms. The recombinant P450scc produced in COS-7 cells efficiently catalyzed the conversion of 25-hydroxycholesterol into pregnenolone. By northern blot, a single P450scc transcript of approximately 3.3 kb was detected in both ovary and head kidney. Transcript levels of this enzyme significantly increased throughout ovarian development artificially induced by salmon pituitary homogenate, which suggests that gonadotropic stimuli can induce ovarian expression of the P450scc gene in teleosts, as has been reported in mammals. Furthermore, RT-PCR analysis revealed that gene expression of three steroidogenic enzymes, P450scc, P450c17 and 3beta-hydroxysteroid dehydrogenase (3beta-HSD) show distinctly different tissue-specific patterns of expression in the Japanese eel. The P450scc gene was expressed in ovary and head kidney while the sole source of the P450c17 transcript was ovary. In contrast, 3beta-HSD transcript was detected in all tissues examined, brain, liver, spleen and trunk kidney, etc. These suggest that some steroidogenic enzymes are also expressed in non-endocrine tissues and could potentially regulate the local and/or circulating steroid levels in teleosts, as they do in mammals.
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Affiliation(s)
- Yukinori Kazeto
- Division of Marine Life Sciences, Research Faculty of Fisheries Science, Hokkaido University, Hakodate, Hokkaido 041-8611, Japan.
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Storbeck KH, Swart P, Graham S, Swart AC. The influence of the amino acid substitution I98K on the catalytic activity of baboon cytochrome P450 side-chain cleavage (CYP11A1). Endocr Res 2004; 30:761-7. [PMID: 15666823 DOI: 10.1081/erc-200044031] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Cytochrome P450 side-chain cleavage (CYP11A1) catalyzes the first and "rate-limiting" step in steroidogenesis, the conversion of cholesterol to pregnenolone. In an effort to gain further insight into the structure/function relationship of this key enzyme, CYP11A1 was characterized in the Cape baboon (Papio ursinus), a species closely related to humans. Baboon cDNA was isolated from adrenal tissue and direct sequence analysis showed mature baboon and human CYP11A1 share 98% deduced amino acid homology. The cDNA was subsequently amplified and two recombinant constructs, CYP11A1a and CYP11A1b, were cloned. Sequence analyses of the constructs revealed four amino acid substitutions. The constructs were expressed in nonsteroidogenic mammalian COS-1 cells with 25-hydroxycholesterol as substrate. Apparent Km values of 1.62 and 4.53 microM were determined for CYP11A1a and CYP11A1b, respectively. Homology modeling revealed that the lower substrate affinity of CYP11B1b could be attributed to an I98K substitution, which lies between the B and C helices, providing further evidence for the importance of this domain in the catalytic activity of CYP11A1.
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Affiliation(s)
- K H Storbeck
- Department of Biochemistry, University of Stellenbosch, Stellenbosch, South Africa
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