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Martinez F, Olvera-Sanchez S, Esparza-Perusquia M, Gomez-Chang E, Flores-Herrera O. Multiple functions of syncytiotrophoblast mitochondria. Steroids 2015; 103:11-22. [PMID: 26435077 DOI: 10.1016/j.steroids.2015.09.006] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Revised: 09/16/2015] [Accepted: 09/27/2015] [Indexed: 12/17/2022]
Abstract
The human placenta plays a central role in pregnancy, and the syncytiotrophoblast cells are the main components of the placenta that support the relationship between the mother and fetus, in apart through the production of progesterone. In this review, the metabolic processes performed by syncytiotrophoblast mitochondria associated with placental steroidogenesis are described. The metabolism of cholesterol, specifically how this steroid hormone precursor reaches the mitochondria, and its transformation into progesterone are reviewed. The role of nucleotides in steroidogenesis, as well as the mechanisms associated with signal transduction through protein phosphorylation and dephosphorylation of proteins is discussed. Finally, topics that require further research are identified, including the need for new techniques to study the syncytiotrophoblast in situ using non-invasive methods.
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Affiliation(s)
- Federico Martinez
- Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, Apdo. Postal 70-159, Coyoacan 04510, México, D.F., Mexico.
| | - Sofia Olvera-Sanchez
- Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, Apdo. Postal 70-159, Coyoacan 04510, México, D.F., Mexico
| | - Mercedes Esparza-Perusquia
- Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, Apdo. Postal 70-159, Coyoacan 04510, México, D.F., Mexico
| | - Erika Gomez-Chang
- Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, Apdo. Postal 70-159, Coyoacan 04510, México, D.F., Mexico
| | - Oscar Flores-Herrera
- Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, Apdo. Postal 70-159, Coyoacan 04510, México, D.F., Mexico
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Esparza-Perusquía M, Olvera-Sánchez S, Flores-Herrera O, Flores-Herrera H, Guevara-Flores A, Pardo JP, Espinosa-García MT, Martínez F. Mitochondrial proteases act on STARD3 to activate progesterone synthesis in human syncytiotrophoblast. Biochim Biophys Acta Gen Subj 2014; 1850:107-17. [PMID: 25459514 DOI: 10.1016/j.bbagen.2014.10.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Revised: 10/06/2014] [Accepted: 10/10/2014] [Indexed: 11/17/2022]
Abstract
BACKGROUND STARD1 transports cholesterol into mitochondria of acutely regulated steroidogenic tissue. It has been suggested that STARD3 transports cholesterol in the human placenta, which does not express STARD1. STARD1 is proteolytically activated into a 30-kDa protein. However, the role of proteases in STARD3 modification in the human placenta has not been studied. METHODS Progesterone determination and Western blot using anti-STARD3 antibodies showed that mitochondrial proteases cleave STARD3 into a 28-kDa fragment that stimulates progesterone synthesis in isolated syncytiotrophoblast mitochondria. Protease inhibitors decrease STARD3 transformation and steroidogenesis. RESULTS STARD3 remained tightly bound to isolated syncytiotrophoblast mitochondria. Simultaneous to the increase in progesterone synthesis, STARD3 was proteolytically processed into four proteins, of which a 28-kDa protein was the most abundant. This protein stimulated mitochondrial progesterone production similarly to truncated-STARD3. Maximum levels of protease activity were observed at pH7.5 and were sensitive to 1,10-phenanthroline, which inhibited steroidogenesis and STARD3 proteolytic cleavage. Addition of 22(R)-hydroxycholesterol increased progesterone synthesis, even in the presence of 1,10-phenanthroline, suggesting that proteolytic products might be involved in mitochondrial cholesterol transport. CONCLUSION Metalloproteases from human placental mitochondria are involved in steroidogenesis through the proteolytic activation of STARD3. 1,10-Phenanthroline inhibits STARD3 proteolytic cleavage. The 28-kDa protein and the amino terminal truncated-STARD3 stimulate steroidogenesis in a comparable rate, suggesting that both proteins share similar properties, probably the START domain that is involved in cholesterol binding. GENERAL SIGNIFICANCE Mitochondrial proteases are involved in syncytiotrophoblast-cell steroidogenesis regulation. Understanding STARD3 activation and its role in progesterone synthesis is crucial to getting insight into its action mechanism in healthy and diseased syncytiotrophoblast cells.
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Affiliation(s)
| | - Sofía Olvera-Sánchez
- Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico
| | - Oscar Flores-Herrera
- Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico
| | - Héctor Flores-Herrera
- Departamento de Bioquímica y Biología Molecular, Instituto Nacional de Perinatología "Isidro Espinosa de los Reyes", Mexico
| | - Alberto Guevara-Flores
- Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico
| | - Juan Pablo Pardo
- Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico
| | | | - Federico Martínez
- Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico.
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Flores-Herrera O, Olvera-Sánchez S, Esparza-Perusquía M, Pardo JP, Rendón JL, Mendoza-Hernández G, Martínez F. Membrane potential regulates mitochondrial ATP-diphosphohydrolase activity but is not involved in progesterone biosynthesis in human syncytiotrophoblast cells. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2014; 1847:143-152. [PMID: 25444704 DOI: 10.1016/j.bbabio.2014.10.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Revised: 09/17/2014] [Accepted: 10/07/2014] [Indexed: 11/26/2022]
Abstract
ATP-diphosphohydrolase is associated with human syncytiotrophoblast mitochondria. The activity of this enzyme is implicated in the stimulation of oxygen uptake and progesterone synthesis. We reported previously that: (1) the detergent-solubilized ATP-diphosphohydrolase has low substrate specificity, and (2) purine and pyrimidine nucleosides, tri- or diphosphates, are fully dephosphorylated in the presence of calcium or magnesium (Flores-Herrera 1999, 2002). In this study we show that ATP-diphosphohydrolase hydrolyzes first the nucleoside triphosphate to nucleoside diphosphate, and then to nucleotide monophosphate, in the case of all tested nucleotides. The activation energies (Ea) for ATP, GTP, UTP, and CTP were 6.06, 4.10, 6.25, and 5.26 kcal/mol, respectively; for ADP, GDP, UDP, and CDP, they were 4.67, 5.42, 5.43, and 6.22 kcal/mol, respectively. The corresponding Arrhenius plots indicated a single rate-limiting step for each hydrolyzed nucleoside, either tri- or diphosphate. In intact mitochondria, the ADP produced by ATP-diphosphohydrolase activity depolarized the membrane potential (ΔΨm) and stimulated oxygen uptake. Mitochondrial respiration showed the state-3/state-4 transition when ATP was added, suggesting that ATP-diphosphohydrolase and the F1F0-ATP synthase work in conjunction to avoid a futile cycle. Substrate selectivity of the ATP-diphosphohydrolase was modified by ΔΨm (i.e. ATP was preferred over GTP when the inner mitochondrial membrane was energized). In contrast, dissipation of ΔΨm by CCCP produced a loss of substrate specificity and so the ATP-diphosphohydrolase was able to hydrolyze ATP and GTP at the same rate. In intact mitochondria, ATP hydrolysis increased progesterone synthesis as compared with GTP. Although dissipation of ΔΨm by CCCP decreased progesterone synthesis, NADPH production restores steroidogenesis. Overall, our results suggest a novel physiological role for ΔΨm in steroidogenesis.
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Affiliation(s)
- Oscar Flores-Herrera
- Universidad Nacional Autónoma de México, Facultad de Medicina, Departamento de Bioquímica y Biología Molecular, México City, Mexico.
| | - Sofia Olvera-Sánchez
- Universidad Nacional Autónoma de México, Facultad de Medicina, Departamento de Bioquímica y Biología Molecular, México City, Mexico
| | - Mercedes Esparza-Perusquía
- Universidad Nacional Autónoma de México, Facultad de Medicina, Departamento de Bioquímica y Biología Molecular, México City, Mexico
| | - Juan Pablo Pardo
- Universidad Nacional Autónoma de México, Facultad de Medicina, Departamento de Bioquímica y Biología Molecular, México City, Mexico
| | - Juan Luis Rendón
- Universidad Nacional Autónoma de México, Facultad de Medicina, Departamento de Bioquímica y Biología Molecular, México City, Mexico
| | - Guillermo Mendoza-Hernández
- Universidad Nacional Autónoma de México, Facultad de Medicina, Departamento de Bioquímica y Biología Molecular, México City, Mexico
| | - Federico Martínez
- Universidad Nacional Autónoma de México, Facultad de Medicina, Departamento de Bioquímica y Biología Molecular, México City, Mexico
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Gomez-Concha C, Flores-Herrera O, Olvera-Sanchez S, Espinosa-Garcia MT, Martinez F. Progesterone synthesis by human placental mitochondria is sensitive to PKA inhibition by H89. Int J Biochem Cell Biol 2011; 43:1402-11. [PMID: 21689781 DOI: 10.1016/j.biocel.2011.06.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2011] [Revised: 05/27/2011] [Accepted: 06/06/2011] [Indexed: 11/24/2022]
Abstract
The transfer of cholesterol to mitochondria, which might involve the phosphorylation of proteins, is the rate-limiting step in human placental steroidogenesis. Protein kinase A (PKA) activity and its role in progesterone synthesis by human placental mitochondria were assessed in this study. The results showed that PKA and phosphotyrosine phosphatase D1 are associated with syncytiotrophoblast mitochondrial membrane by an anchoring kinase cAMP protein-121. The ³²P-labeled of four major proteins was analyzed. The specific inhibitor of PKA, H89, decreased progesterone synthesis in mitochondria while in mitochondrial steroidogenic contact sites protein-phosphorylation was diminished, suggesting that PKA plays a role in placental hormone synthesis. In isolated mitochondria, PKA activity was unaffected by the addition of cAMP suggesting a constant activity of this kinase in the syncytiotrophoblast. The presence of PKA and phosphotyrosine phosphatase D1 anchored to mitochondria by an anchoring kinase cAMP protein-121 indicated that syncytiotrophoblast mitochondria contain a full phosphorylation/dephosphorylation system.
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Affiliation(s)
- Cuauhtemoc Gomez-Concha
- Departamento de Bioquimica, Facultad de Medicina, Universidad Nacional Autónoma de México, Apartado Postal 70-159, Coyoacan 04510, Mexico, D.F., Mexico
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De los Rios Castillo D, Zarco-Zavala M, Olvera-Sanchez S, Pardo JP, Juarez O, Martinez F, Mendoza-Hernandez G, García-Trejo JJ, Flores-Herrera O. Atypical cristae morphology of human syncytiotrophoblast mitochondria: role for complex V. J Biol Chem 2011; 286:23911-9. [PMID: 21572045 DOI: 10.1074/jbc.m111.252056] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Mitochondrial complexes I, III(2), and IV from human cytotrophoblast and syncytiotrophoblast associate to form supercomplexes or respirasomes, with the following stoichiometries: I(1):(III(2))(1) and I(1):(III(2))(1-2):IV(1-4). The content of respirasomes was similar in both cell types after isolating mitochondria. However, syncytiotrophoblast mitochondria possess low levels of dimeric complex V and do not have orthodox cristae morphology. In contrast, cytotrophoblast mitochondria show normal cristae morphology and a higher content of ATP synthase dimer. Consistent with the dimerizing role of the ATPase inhibitory protein (IF(1)) (García, J. J., Morales-Ríos, E., Cortés-Hernandez, P., and Rodríguez-Zavala, J. S. (2006) Biochemistry 45, 12695-12703), higher relative amounts of IF(1) were observed in cytotrophoblast when compared with syncytiotrophoblast mitochondria. Therefore, there is a correlation between dimerization of complex V, IF(1) expression, and the morphology of mitochondrial cristae in human placental mitochondria. The possible relationship between cristae architecture and the physiological function of the syncytiotrophoblast mitochondria is discussed.
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Affiliation(s)
- Daniela De los Rios Castillo
- Department of Biochemistry and Molecular Biology, Medicine Faculty, National Autonomous University of Mexico, 04510 Mexico City, Mexico
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Ohnuma S, Chufan E, Nandigama K, Miller Jenkins LM, Durell SR, Appella E, Sauna ZE, Ambudkar SV. Inhibition of multidrug resistance-linked P-glycoprotein (ABCB1) function by 5'-fluorosulfonylbenzoyl 5'-adenosine: evidence for an ATP analogue that interacts with both drug-substrate-and nucleotide-binding sites. Biochemistry 2011; 50:3724-35. [PMID: 21452853 PMCID: PMC3108491 DOI: 10.1021/bi200073f] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
5'-Fluorosulfonylbenzonyl 5'-adenosine (FSBA) is an ATP analogue that covalently modifies several residues in the nucleotide-binding domains (NBDs) of several ATPases, kinases, and other proteins. P-glycoprotein (P-gp, ABCB1) is a member of the ATP-binding cassette (ABC) transporter superfamily that utilizes energy from ATP hydrolysis for the efflux of amphipathic anticancer agents from cancer cells. We investigated the interactions of FSBA with P-gp to study the catalytic cycle of ATP hydrolysis. Incubation of P-gp with FSBA inhibited ATP hydrolysis (IC(50 )= 0.21 mM) and the binding of 8-azido[α-(32)P]ATP (IC(50) = 0.68 mM). In addition, (14)C-FSBA cross-links to P-gp, suggesting that FSBA-mediated inhibition of ATP hydrolysis is irreversible due to covalent modification of P-gp. However, when the NBDs were occupied with a saturating concentration of ATP prior to treatment, FSBA stimulated ATP hydrolysis by P-gp. Furthermore, FSBA inhibited the photo-cross-linking of P-gp with [(125)I]iodoarylazidoprazosin (IAAP; IC(50) = 0.17 mM). As IAAP is a transport substrate for P-gp, this suggests that FSBA affects not only the NBDs but also the transport-substrate site in the transmembrane domains. Consistent with these results, FSBA blocked efflux of rhodamine 123 from P-gp-expressing cells. Additionally, mass spectrometric analysis identified FSBA cross-links to residues within or nearby the NBDs but not in the transmembrane domains, and docking of FSBA in a homology model of human P-gp NBDs supports the biochemical studies. Thus, FSBA is an ATP analogue that interacts with both the drug-binding and ATP-binding sites of P-gp, but fluorosulfonyl-mediated cross-linking is observed only at the NBDs.
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Affiliation(s)
- Shinobu Ohnuma
- Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892-4256
| | - Eduardo Chufan
- Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892-4256
| | - Krishnamachary Nandigama
- Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892-4256
| | - Lisa M. Miller Jenkins
- Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892-4256
| | - Stewart R. Durell
- Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892-4256
| | - Ettore Appella
- Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892-4256
| | - Zuben E. Sauna
- Laboratory of Hemostasis, Division of Hematology, Center for Biologics Evaluation and Research, US Food and Drug Administration, Bethesda, Maryland 20892
| | - Suresh V. Ambudkar
- Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892-4256
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Contribution of Potassium in Human Placental Steroidogenesis. Placenta 2010; 31:860-6. [DOI: 10.1016/j.placenta.2010.07.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2010] [Revised: 07/04/2010] [Accepted: 07/17/2010] [Indexed: 11/22/2022]
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Maldonado-Mercado MG, Espinosa-García MT, Gómez-Concha C, Monreal-Flores J, Martinez F. Steroidogenesis in BeWo cells: role of protein kinase A and benzodiazepines. Int J Biochem Cell Biol 2007; 40:901-8. [PMID: 18069041 DOI: 10.1016/j.biocel.2007.10.026] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2007] [Revised: 10/08/2007] [Accepted: 10/23/2007] [Indexed: 11/25/2022]
Abstract
The peripheral benzodiazepine receptor and protein kinase A have been proposed to modulate placental steroidogenesis. Binding of the radioactive benzodiazepine PK 11195 has been observed in membranes isolated from whole human placenta, but the presence of the peripheral benzodiazepine receptors, now called translocator protein, does not seem to be indispensable. We hypothesized that cAMP analogs could induce the translocator protein expression in BeWo cells increasing steroidogenesis in the presence of benzodiazepines. The effect of two benzodiazepines and of 8-Br-cAMP on steroidogenesis in BeWo cells or in isolated human placental mitochondria was studied. Benzodiazepines did not modify progesterone synthesis in either system. Progesterone increased three times in BeWo cells incubated in the presence of 8-Br-cAMP. The translocator protein was not identified by western blot in mitochondria isolated from either the human placenta or BeWo cells but it was present in isolated rat testicular mitochondria. Neither was it observed in isolated mitochondria from BeWo cells incubated with 8-Br-cAMP. An inhibitor of protein kinase A activity, H89, at 25 microM inhibited 90% the steroidogenesis in BeWo cells, even in the presence of 8-Br-cAMP, but protein phosphorylation in mitochondria increased in the presence of H89, suggesting that protein kinase A modulates the phosphorylation cycle of mitochondrial proteins. The results suggest that placental steroidogenesis is regulated via activation of protein kinase A modulated by cAMP.
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Kettlun AM, Espinosa V, García L, Valenzuela MA. Potato tuber isoapyrases: substrate specificity, affinity labeling, and proteolytic susceptibility. PHYTOCHEMISTRY 2005; 66:975-82. [PMID: 15896365 DOI: 10.1016/j.phytochem.2005.03.015] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2004] [Revised: 12/10/2004] [Indexed: 05/02/2023]
Abstract
Apyrase/ATP-diphosphohydrolase hydrolyzes di- and triphosphorylated nucleosides in the presence of a bivalent ion with sequential release of orthophosphate. We performed studies of substrate specificity on homogeneous isoapyrases from two potato tuber clonal varieties: Desiree (low ATPase/ADPase ratio) and Pimpernel (high ATPase/ADPase ratio) by measuring the kinetic parameters K(m) and k(cat) on deoxyribonucleotides and fluorescent analogues of ATP and ADP. Both isoapyrases showed a broad specificity towards dATP, dGTP, dTTP, dCTP, thio-dATP, fluorescent nucleotides (MANT-; TNP-; ethene-derivatives of ATP and ADP). The hydrolytic activity on the triphosphorylated compounds was always higher for the Pimpernel apyrase. Modifications either on the base or the ribose moieties did not increase K(m) values, suggesting that the introduction of large groups (MANT- and TNP-) in the ribose does not produce steric hindrance on substrate binding. However, the presence of these bulky groups caused, in general, a reduction in k(cat), indicating an important effect on the catalytic step. Substantial differences were observed between potato apyrases and enzymes from various animal tissues, concerning affinity labeling with azido-nucleotides and FSBA (5'-p-fluorosulfonylbenzoyl adenosine). PLP-nucleotide derivatives were unable to produce inactivation of potato apyrase. The lack of sensitivity of both potato enzymes towards these nucleotide analogues rules out the proximity or adequate orientation of sulfhydryl, hydroxyl or amino-groups to the modifying groups. Both apyrases were different in the proteolytic susceptibility towards trypsin, chymotrypsin and Glu-C.
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Affiliation(s)
- A M Kettlun
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Casilla 233, Correo 1, Santiago, Chile
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Uribe A, Strauss JF, Martínez F. Contact sites from human placental mitochondria: characterization and role in progesterone synthesis. Arch Biochem Biophys 2003; 413:172-81. [PMID: 12729614 DOI: 10.1016/s0003-9861(03)00097-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
To understand the functional compartmentalization of human placental mitochondria, we analyzed the composition and steroidogenic activity of contact sites. Several fractions containing contact sites were isolated using osmotic shock treatment and sucrose gradient centrifugation. These fractions contained various proteins and marker enzymes associated with mitochondrial membranes. The fractions containing the cytochrome P450 side chain cleavage system, cholesterol, nicotinamide adenine dinucleotide phosphate-isocitrate dehydrogenase, porin, and adenosine 5(')-triphosphate-diphosphohydrolase activity showed the capacity to synthesize progesterone. Our observations indicate that all necessary elements and enzymes for steroidogenesis are present and functional in placental mitochondrial contact sites. This organization may facilitate the metabolism of cholesterol delivered to the outer mitochondrial membrane into steroid hormones by the inner mitochondrial membrane cholesterol side chain cleavage system.
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Affiliation(s)
- Aida Uribe
- Departamento de Bioquimica, Facultad de Medicina, Universidad Nacional Autonoma de Mexico, Apdo. Postal 70-159, 04510 Mexico, DF, Mexico
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