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Li Y, Zheng Z, Luo D, Liu C, Yang S, Chen Y, Hu Q, Lu W, Wang Y, Mei S. Reproductive hormones, organophosphate esters and semen quality: Exploring associations and mediation effects among men from an infertility clinic. ENVIRONMENTAL RESEARCH 2024; 240:117458. [PMID: 37884071 DOI: 10.1016/j.envres.2023.117458] [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: 05/28/2023] [Revised: 10/09/2023] [Accepted: 10/19/2023] [Indexed: 10/28/2023]
Abstract
Accumulating evidence indicates that organophosphate esters (OPEs) exposure may affect semen quality. As a crucial factor in male reproduction, reproductive hormones might be linked organophosphate esters (OPEs) exposure and semen quality. This study aimed to explore the mediating role of reproductive hormones on the association between OPEs exposure and semen quality. Five serum reproductive hormones, semen quality, and 16 urinary OPE metabolites were measured among 491 reproductive-aged men from a reproductive center. The associations of urinary OPE metabolites with reproductive hormones and semen quality were assessed using multivariable linear regression models, and the mediating role of reproductive hormones was evaluated by mediation analyses. We found that follicle stimulating hormone (FSH) was positively associated with diphenyl phosphate (DPHP) that in turn was negatively associated with sperm total count. In addition, inverse associations were exhibited between serum FSH and sperm concentration, sperm total count, total motility, and progressive motility (all Ptrend <0.05). Mediation analysis further showed that FSH mediated 13.7% of the inverse association of DPHP and sperm total count. Although further investigations are required, our results suggest that FSH was an intermediate mechanism in the associations between OPEs exposure and impaired semen quality.
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Affiliation(s)
- Yaping Li
- State Key Laboratory of Environment Health (Incubation), Key Laboratory of Environment and Health, Ministry of Education, Key Laboratory of Environment and Health (Wuhan), Ministry of Environmental Protection, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, #13 Hangkong Road, Wuhan, Hubei, 430030, China
| | - Zhiyi Zheng
- State Key Laboratory of Environment Health (Incubation), Key Laboratory of Environment and Health, Ministry of Education, Key Laboratory of Environment and Health (Wuhan), Ministry of Environmental Protection, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, #13 Hangkong Road, Wuhan, Hubei, 430030, China
| | - Dan Luo
- Department of Preventive Medicine, School of Public Health, Guangzhou Medical University, Guangzhou, 511436, China
| | - Chong Liu
- State Key Laboratory of Environment Health (Incubation), Key Laboratory of Environment and Health, Ministry of Education, Key Laboratory of Environment and Health (Wuhan), Ministry of Environmental Protection, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, #13 Hangkong Road, Wuhan, Hubei, 430030, China; Department of Occupational and Environmental Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Sijie Yang
- State Key Laboratory of Environment Health (Incubation), Key Laboratory of Environment and Health, Ministry of Education, Key Laboratory of Environment and Health (Wuhan), Ministry of Environmental Protection, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, #13 Hangkong Road, Wuhan, Hubei, 430030, China
| | - Yingjun Chen
- Southern Medical University Department of Epidemiology, School of Public Health, Southern Medical University, Guangzhou, Guangdong, China
| | - Qian Hu
- State Key Laboratory of Environment Health (Incubation), Key Laboratory of Environment and Health, Ministry of Education, Key Laboratory of Environment and Health (Wuhan), Ministry of Environmental Protection, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, #13 Hangkong Road, Wuhan, Hubei, 430030, China
| | - Wenqing Lu
- State Key Laboratory of Environment Health (Incubation), Key Laboratory of Environment and Health, Ministry of Education, Key Laboratory of Environment and Health (Wuhan), Ministry of Environmental Protection, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, #13 Hangkong Road, Wuhan, Hubei, 430030, China; Department of Occupational and Environmental Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Yixin Wang
- Department of Environmental Health, School of Public Health, Shanghai Jiao Tong University School of Medicine, 227 South Chongqing Rd, Shanghai 200025, China; Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, USA.
| | - Surong Mei
- State Key Laboratory of Environment Health (Incubation), Key Laboratory of Environment and Health, Ministry of Education, Key Laboratory of Environment and Health (Wuhan), Ministry of Environmental Protection, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, #13 Hangkong Road, Wuhan, Hubei, 430030, China.
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Hernández N, Sánchez-Mateos S, López-Morató M, Sánchez-Margallo FM, Álvarez IS. Effect of the addition of 4OHE 2 and quercetin in culture media on ROS levels and gene expression in mouse blastocysts. Reprod Fertil Dev 2022; 34:980-990. [PMID: 36075881 DOI: 10.1071/rd22041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 08/11/2022] [Indexed: 11/23/2022] Open
Abstract
AIMS The main objective of this work is to elucidate whether Quercetin (Qc) and 4-Hidroxistradiol (4OHE2 ) decrease the level of reactive oxygen species (ROS) in in vitro obtained embryos and to analyse which genes are activated under the treatments that could explain this improvement. METHODS Oxidative stress was induced during embryo culture by H2 O2 treatment and ROS production was measured and compared with embryos treated with Qc or 4OHE2 . Gene expression was analysed by Q-PCR in control embryos obtained in utero (IU) or by IVF and compared with the levels found in embryos cultured with Qc or 4OHE2 to determine the effect of these compounds. KEY RESULTS Qc strongly reduces ROS levels in embryos after a treatment of 4h. On the contrary, 4OHE2 had no effect in reducing ROS levels in embryos. The addition of these molecules to the culture media upregulate several hypoxia-related genes when Qc is added to the culture media, and implantation-related genes when 4OHE2 is used. CONCLUSIONS Qc is a very strong antioxidant molecule that when used for short periods of time during culture can reduce ROS levels and improve embryo quality by activating antioxidant enzymes. 4OHE2 supplementation, despite having no effects in reducing ROS levels, acts directly in the molecular signalling implicated in the implantation process and could be also considered as a supplement for embryo culture during IVF. IMPLICATIONS Proper supplementation of the culture media could greatly improve the quality of embryos cultured in vitro , resulting in better results in IVF clinics.
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Affiliation(s)
- Nuria Hernández
- Criopreservation Facility, Biomedicine Institute, Seville, Spain; and Assisted Reproduction Unit, Jesús Usón Minimally Invasive Surgery Centre, Cáceres, Spain.á
| | - Soledad Sánchez-Mateos
- Assisted Reproduction Unit, Jesús Usón Minimally Invasive Surgery Centre, Cáceres, Spain.á
| | - Marta López-Morató
- Assisted Reproduction Unit, Jesús Usón Minimally Invasive Surgery Centre, Cáceres, Spain.á; and Genetics Unit, Hospital HLA Vistahermosa, Alicante, Spain
| | | | - Ignacio S Álvarez
- Department of Cell Biology, University of Extremadura, Badajoz, Spain; and Instituto Extremeño de Reproduccion Asistida (IERA), Badajoz, Spain
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Lee I, Zhang G, Mesaros C, Penning TM. Estrogen receptor-dependent and independent roles of benzo[a]pyrene in Ishikawa cells. J Endocrinol 2020; 247:139-151. [PMID: 32992293 PMCID: PMC7534831 DOI: 10.1530/joe-19-0579] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 08/26/2020] [Indexed: 01/12/2023]
Abstract
Polycyclic aromatic hydrocarbons (PAHs) are environmental pollutants generated from the incomplete combustion of organic material. PAHs have been studied as genotoxicants, but some also act via non-genotoxic mechanisms in estrogen-dependent malignancies, such as breast cancer. PAHs require metabolic activation to electrophilic metabolites to exert their genotoxicity but non-genotoxic properties may also contribute to their carcinogenicity. The role of PAHs in endometrial cancer, a cancer associated with unopposed estrogen action is unknown. We assessed the metabolism of the representative PAH, benzo[a]pyrene (B[a]P), to estrogenic compounds in Ishikawa human endometrial cells in the presence and absence of cytochrome P450 induction. Using stable-isotope dilution high-performance liquid chromatography and APCI tandem mass spectrometry in the selected reaction monitoring mode, we analyzed B[a]P metabolism in Ishikawa cells. Estrogenic activity of B[a]P metabolites was determined by the endogenous estrogen inducible alkaline phosphatase reporter gene and an exogenous estrogen response element (ERE) luciferase reporter gene construct. We also assessed whether PAHs can induce a proliferative phenotype via estrogen receptor (ER)- and non-ER-regulated pathways. We demonstrate that B[a]P can be metabolized in human endometrial cells into 3-OH-B[a]P and B[a]P-7,8-dione in sufficient amounts to activate ERs. We also show that only B[a]P-7,8-dione induces endometrial cell proliferation at concentrations lower than required to activate the ER; instead non-genomic signaling by the EGF receptor (EGFR) and activation of the mitogen-activated protein kinase (MAPK) pathway was responsible. This work indicates that human endometrial cells can metabolize PAHs into estrogenic metabolites, which may induce cell proliferation through non-ER-regulated pathways.
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Affiliation(s)
- Isabelle Lee
- Department of Systems Pharmacology & Translational Therapeutics Perelman School of Medicine University of Philadelphia, Pennsylvania, PA 19104
| | - Guannan Zhang
- Department of Systems Pharmacology & Translational Therapeutics Perelman School of Medicine University of Philadelphia, Pennsylvania, PA 19104
- Center of Excellence in Environmental Toxicology Perelman School of Medicine University of Philadelphia, Pennsylvania, PA 19104
| | - Clementina Mesaros
- Department of Systems Pharmacology & Translational Therapeutics Perelman School of Medicine University of Philadelphia, Pennsylvania, PA 19104
- Center of Excellence in Environmental Toxicology Perelman School of Medicine University of Philadelphia, Pennsylvania, PA 19104
| | - Trevor M. Penning
- Department of Systems Pharmacology & Translational Therapeutics Perelman School of Medicine University of Philadelphia, Pennsylvania, PA 19104
- Center of Excellence in Environmental Toxicology Perelman School of Medicine University of Philadelphia, Pennsylvania, PA 19104
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Luja-Mondragón M, Gómez-Oliván LM, SanJuan-Reyes N, Islas-Flores H, Orozco-Hernández JM, Heredia-García G, Galar-Martínez M, Dublán-García O. Alterations to embryonic development and teratogenic effects induced by a hospital effluent on Cyprinus carpio oocytes. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 660:751-764. [PMID: 30743961 DOI: 10.1016/j.scitotenv.2019.01.072] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Revised: 01/07/2019] [Accepted: 01/07/2019] [Indexed: 06/09/2023]
Abstract
Hospital functioning generates a great quantity of contaminants, among which organic materials, heavy metals, and diverse pharmaceuticals are noteworthy that can affect organisms if they are not properly removed from the effluents. The hospital effluent evaluated in the present study came from IMSS (Instituto Mexicano del Seguro Social) Clinic 221 in downtown Toluca, State of Mexico, a secondary care facility. The contaminants identified in hospitals have been associated with deleterious effects on aquatic organisms; however, it is necessary to continue with more studies in order to be able to regulate the production of said contaminants which are generally dumped into the city sewage system. The present study had the purpose of evaluating the alterations to embryonic development and teratogenic effects on oocytes Cyprinus carpio after exposure to different proportions of hospital effluent. For said purpose, the physicochemical properties of the effluent were determined. Concentrations of the main microcontaminants were also determined. An embryolethality study out and the determination of the main alterations to embryonic development and teratogenic effects produced, due to exposure of C. carpio at different proportions of the effluent, were carried out. The results showed that the physicochemical properties were within the values permitted by Mexican regulation; however, the presence of contaminants such as NaClO, metals, anti-biotics, anti-diabetics, non-steroidal anti-inflammatory drugs, hormones and beta-blockers, was detected. Lethal concentration 50 was 5.65% and the effective concentration for malformations was 3.85%, with a teratogenic index of 1.46. The main teratogenic alterations were yolk deformation, scoliosis, modified chorda structure, tail malformation, fin deformity and mouth hyperplasia. A high rate of hatching delay was observed. The results suggest that the hospital effluent under study is capable of inducing embryotoxicity and teratogenicity in oocytes of C. carpio.
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Affiliation(s)
- Marlenne Luja-Mondragón
- Environmental Toxicology Laboratory, School of Chemistry, Autonomous University of the State of Mexico, Intersection of Paseo Colón and Paseo Tollocan, Residencial Colón neighborhood, 50120 Toluca, State of Mexico, Mexico
| | - Leobardo Manuel Gómez-Oliván
- Environmental Toxicology Laboratory, School of Chemistry, Autonomous University of the State of Mexico, Intersection of Paseo Colón and Paseo Tollocan, Residencial Colón neighborhood, 50120 Toluca, State of Mexico, Mexico.
| | - Nely SanJuan-Reyes
- Aquatic Toxicology Laboratory, Pharmacy Department, National Institute of Biological Sciences, National Polytechnic Institute, Adolfo López Mateos Professional Unit, Wilfrido Massieu Ave., Gustavo A. Madero District, Mexico City 07738, Mexico
| | - Hariz Islas-Flores
- Environmental Toxicology Laboratory, School of Chemistry, Autonomous University of the State of Mexico, Intersection of Paseo Colón and Paseo Tollocan, Residencial Colón neighborhood, 50120 Toluca, State of Mexico, Mexico
| | - José Manuel Orozco-Hernández
- Environmental Toxicology Laboratory, School of Chemistry, Autonomous University of the State of Mexico, Intersection of Paseo Colón and Paseo Tollocan, Residencial Colón neighborhood, 50120 Toluca, State of Mexico, Mexico
| | - Gerardo Heredia-García
- Environmental Toxicology Laboratory, School of Chemistry, Autonomous University of the State of Mexico, Intersection of Paseo Colón and Paseo Tollocan, Residencial Colón neighborhood, 50120 Toluca, State of Mexico, Mexico
| | - Marcela Galar-Martínez
- Aquatic Toxicology Laboratory, Pharmacy Department, National Institute of Biological Sciences, National Polytechnic Institute, Adolfo López Mateos Professional Unit, Wilfrido Massieu Ave., Gustavo A. Madero District, Mexico City 07738, Mexico
| | - Octavio Dublán-García
- Environmental Toxicology Laboratory, School of Chemistry, Autonomous University of the State of Mexico, Intersection of Paseo Colón and Paseo Tollocan, Residencial Colón neighborhood, 50120 Toluca, State of Mexico, Mexico
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Meng X, Sun H, Yang L, Yin R, Qi L. A hydroxylated flavonol, fisetin inhibits the formation of a carcinogenic estrogen metabolite. Steroids 2017; 119:53-56. [PMID: 28119082 DOI: 10.1016/j.steroids.2017.01.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Revised: 01/10/2017] [Accepted: 01/12/2017] [Indexed: 12/22/2022]
Abstract
Fisetin can be found in a wide variety of plants and possesses strong efficacy against many cancers. 17β-Estradiol (E2) is hydrolyzed to 4-hydroxy-E2 (4-OHE2) via cytochrome P450 (CYP) 1B1 in vivo. In estrogen target tissues including the mammary gland, ovaries, and uterus, CYP1B1 is highly expressed, and 4-OHE2 is predominantly formed in cancerous tissues. Herein, we investigated the inhibitory activity of fisetin and flavone against CYP1B1 using estrogen E2 as substrate in vitro to reveal structure-activity relationship between structure of flavonoids and inhibition. The results showed that fisetin possessed inhibitory effect on CYP1B1 activity. Compared with flavone, the inhibition of fisetin was stronger. The Vmax and Ki values were 1.950±0.157pmol/μgprotein/min and 4.925±0.689nM for fisetin and 2.277±0.231pmol/μgprotein/min and 9.148±2.150nM for flavone, respectively. By kinetic analyses, both fisetin and flavone displayed mixed inhibition. Taken together the data suggested that fisetin is able to inhibit the formation of carcinogenic 4-OHE2 from E2, which reveals one of its anti-cancer mechanisms and helps to reveal the relationship between the structure of flavonoids and the inhibition CYP1B1 for discovering new drugs in cancer therapy and prevention.
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Affiliation(s)
- Xin Meng
- School of Pharmacy, Heilongjiang University of Chinese Medicine, No. 24 Heping Road, Harbin 150040, PR China.
| | - Hui Sun
- School of Pharmacy, Heilongjiang University of Chinese Medicine, No. 24 Heping Road, Harbin 150040, PR China
| | - Lianrong Yang
- School of Pharmacy, Heilongjiang University of Chinese Medicine, No. 24 Heping Road, Harbin 150040, PR China
| | - Rui Yin
- School of Pharmacy, Heilongjiang University of Chinese Medicine, No. 24 Heping Road, Harbin 150040, PR China
| | - Lehui Qi
- School of Pharmacy, Heilongjiang University of Chinese Medicine, No. 24 Heping Road, Harbin 150040, PR China
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Jenkins JA, Olivier HM, Draugelis-Dale RO, Eilts BE, Torres L, Patiño R, Nilsen E, Goodbred SL. Assessing reproductive and endocrine parameters in male largescale suckers (Catostomus macrocheilus) along a contaminant gradient in the lower Columbia River, USA. THE SCIENCE OF THE TOTAL ENVIRONMENT 2014; 484:365-378. [PMID: 24182618 DOI: 10.1016/j.scitotenv.2013.09.097] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2013] [Revised: 09/27/2013] [Accepted: 09/28/2013] [Indexed: 06/02/2023]
Abstract
Persistent organochlorine pollutants such as polychlorinated biphenyls (PCBs), dichlorodiphenyldichloroethylene (p,p'-DDE), and polybrominated diphenyl ethers (PBDEs) are stable, bioaccumulative, and widely found in the environment, wildlife, and the human population. To explore the hypothesis that reproduction in male fish is associated with environmental exposures in the lower Columbia River (LCR), reproductive and endocrine parameters were studied in male resident, non-anadromous largescale sucker (Catostomus macrocheilus) (LSS) in the same habitats as anadromous salmonids having conservation status. Testes, thyroid tissue and plasma collected in 2010 from Longview (LV), Columbia City (CC), and Skamania (SK; reference) were studied. Sperm morphologies and thyrocyte heights were measured by light microscopy, sperm motilities by computer-assisted sperm motion analysis, sperm adenosine triphosphate (ATP) with luciferase, and plasma vitellogenin (VTG), thyroxine (T4), and triiodothyronine (T3) by immunoassay. Sperm apoptosis, viability, mitochondrial membrane potential, nuclear DNA fragmentation, and reproductive stage were measured by flow cytometry. Sperm quality parameters (except counts) and VTG were significantly different among sites, with correlations between VTG and 7 sperm parameters. Thyrocyte heights, T4, T3, gonadosomatic index and Fulton's condition factor differed among sites, but not significantly. Sperm quality was significantly lower and VTG higher where liver contaminants and water estrogen equivalents were highest (LV site). Total PCBs (specifically PCB-138, -146, -151, -170, -174, -177, -180, -183, -187, -194, and -206) and total PBDEs (specifically BDE-47, -100, -153, and -154) were negatively correlated with sperm motility. PCB-206 and BDE-154 were positively correlated with DNA fragmentation, and pentachloroanisole and VTG were positively correlated with sperm apoptosis and negatively correlated with ATP. BDE-99 was positively correlated with sperm counts and motility; T4 was negatively correlated with counts and positively correlated with motility, thus indicating possible androgenic mechanisms and thyroid endocrine disruption. Male LSS proved to be an informative model for studying reproductive and endocrine biomarkers in the LCR.
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Affiliation(s)
- J A Jenkins
- U.S. Geological Survey, National Wetlands Research Center, 700 Cajundome Blvd., Lafayette, LA 70506, USA.
| | - H M Olivier
- U.S. Geological Survey, National Wetlands Research Center, 700 Cajundome Blvd., Lafayette, LA 70506, USA
| | - R O Draugelis-Dale
- U.S. Geological Survey, National Wetlands Research Center, 700 Cajundome Blvd., Lafayette, LA 70506, USA
| | - B E Eilts
- Department of Veterinary Clinical Sciences, Louisiana State University, Baton Rouge, LA 70803, USA
| | - L Torres
- Department of Biological Sciences and Texas Cooperative Fish and Wildlife Research Unit, Texas Tech University, Lubbock, TX 79409-3131, USA
| | - R Patiño
- U.S. Geological Survey, Texas Cooperative Fish and Wildlife Unit, Texas Tech University, Lubbock, TX 79409-2120, USA; Department of Biological Sciences and Department of Natural Resources Management, Texas Tech University, Lubbock, TX 79409-2120, USA
| | - E Nilsen
- U.S. Geological Survey, Oregon Water Science Center, 2130 S.W. 5th Avenue, Portland, OR 97201, USA
| | - S L Goodbred
- U.S. Geological Survey (Emeritus), High Point, NC 27262, USA
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Mechanisms of estrogens' dose-dependent neuroprotective and neurodamaging effects in experimental models of cerebral ischemia. Int J Mol Sci 2011; 12:1533-62. [PMID: 21673906 PMCID: PMC3111617 DOI: 10.3390/ijms12031533] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2010] [Revised: 02/10/2011] [Accepted: 02/22/2011] [Indexed: 02/08/2023] Open
Abstract
Ever since the hypothesis was put forward that estrogens could protect against cerebral ischemia, numerous studies have investigated the mechanisms of their effects. Despite initial studies showing ameliorating effects, later trials in both humans and animals have yielded contrasting results regarding the fundamental issue of whether estrogens are neuroprotective or neurodamaging. Therefore, investigations of the possible mechanisms of estrogen actions in brain ischemia have been difficult to assess. A recently published systematic review from our laboratory indicates that the dichotomy in experimental rat studies may be caused by the use of insufficiently validated estrogen administration methods resulting in serum hormone concentrations far from those intended, and that physiological estrogen concentrations are neuroprotective while supraphysiological concentrations augment the damage from cerebral ischemia. This evidence offers a new perspective on the mechanisms of estrogens’ actions in cerebral ischemia, and also has a direct bearing on the hormone replacement therapy debate. Estrogens affect their target organs by several different pathways and receptors, and the mechanisms proposed for their effects on stroke probably prevail in different concentration ranges. In the current article, previously suggested neuroprotective and neurodamaging mechanisms are reviewed in a hormone concentration perspective in an effort to provide a mechanistic framework for the dose-dependent paradoxical effects of estrogens in stroke. It is concluded that five protective mechanisms, namely decreased apoptosis, growth factor regulation, vascular modulation, indirect antioxidant properties and decreased inflammation, and the proposed damaging mechanism of increased inflammation, are currently supported by experiments performed in optimal biological settings.
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