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Jabarpour M, Aleyasin A, Nashtaei MS, Lotfi S, Amidi F. Astaxanthin treatment ameliorates ER stress in polycystic ovary syndrome patients: a randomized clinical trial. Sci Rep 2023; 13:3376. [PMID: 36854788 PMCID: PMC9974957 DOI: 10.1038/s41598-023-28956-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Accepted: 01/27/2023] [Indexed: 03/02/2023] Open
Abstract
Astaxanthin (ASX), as a natural carotenoid compound, exists in various types of seafood and microorganisms. It has several possible beneficial therapeutic effects for patients with polycystic ovary syndrome (PCOS). Patients with PCOS also suffer from endoplasmic reticulum (ER) stress. In the present work, it was hypothesized that ER stress could be improved by ASX in PCOS patients. Granulosa cells (GCs) were obtained from 58 PCOS patients. The patients were classified into ASX treatment (receiving 12 mg/day for 60 days) and placebo groups. The expression levels of ER stress pathway genes and proteins were explored using Western blotting and quantitative polymerase chain reaction. To assess oxidative stress markers, follicular fluid (FF) was gained from all patients. The Student's t test was used to perform statistical analysis. After the intervention, ASX led to a considerable reduction in the expression levels of 78-kDa glucose-regulated protein (GRP78), CCAAT/enhancer-binding protein homologous protein (CHOP), and X-box-binding protein 1 compared to the placebo group, though the reduction in the messenger RNA (mRNA) expression level of activating transcription factor 6 was not statistically significant. However, ASX significantly increased the ATF4 expression level. GRP78 and CHOP protein levels represented a considerable decrease in the treatment group after the intervention. In addition, a statistically significant increase was found in the FF level of total antioxidant capacity in the treatment group. Based on clinical outcomes, no significant differences were found between the groups in terms of the oocyte number, fertilization rate, and fertility rate, but the ASX group had higher rates of high-quality oocytes, high-quality embryo, and oocyte maturity compared to the placebo group. Our findings demonstrated that ER stress in the GCs of PCOS patients could be modulated by ASX by changing the expression of genes and proteins included in the unfolding protein response.Trial registration This study was retrospectively registered on the Iranian Registry of Clinical Trials website ( www.irct.ir ; IRCT-ID: IRCT20201029049183N, 2020-11-27).
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Affiliation(s)
- Masoome Jabarpour
- grid.411705.60000 0001 0166 0922Department of Anatomy, School of Medicine, Tehran University of Medical Sciences, Pour Sina St, Tehran, 1416753955 Iran
| | - Ashraf Aleyasin
- grid.415646.40000 0004 0612 6034Department of Infertility, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Maryam Shabani Nashtaei
- grid.411705.60000 0001 0166 0922Department of Anatomy, School of Medicine, Tehran University of Medical Sciences, Pour Sina St, Tehran, 1416753955 Iran ,grid.415646.40000 0004 0612 6034Department of Infertility, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Sara Lotfi
- grid.411705.60000 0001 0166 0922Department of Anatomy, School of Medicine, Tehran University of Medical Sciences, Pour Sina St, Tehran, 1416753955 Iran
| | - Fardin Amidi
- Department of Anatomy, School of Medicine, Tehran University of Medical Sciences, Pour Sina St, Tehran, 1416753955, Iran. .,Department of Infertility, Yas Hospital, Tehran University of Medical Sciences, Tehran, Iran.
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Kosior MA, Esposito R, Cocchia N, Piscopo F, Longobardi V, Cacciola NA, Presicce GA, Campanile G, Aardema H, Gasparrini B. Seasonal variations in the metabolomic profile of the ovarian follicle components in Italian Mediterranean Buffaloes. Theriogenology 2023; 202:42-50. [PMID: 36898285 DOI: 10.1016/j.theriogenology.2023.02.022] [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: 11/10/2022] [Revised: 02/15/2023] [Accepted: 02/18/2023] [Indexed: 03/05/2023]
Abstract
The aim of this work was to evaluate the seasonal effect on the metabolomic profile of the ovarian follicle in Italian Mediterranean buffalo to unravel the causes of the reduced competence during the non-breeding season (NBS). Samples of follicular fluid, follicular cells, cumulus cells and oocytes were collected from abattoir-derived ovaries during breeding season (BS) and NBS and analyzed by 1H Nuclear Magnetic Resonance. The Orthogonal Projections to Latent Structures of the Discriminant Analysis showed clear separation into seasonal classes and Variable Importance in Projection method identified differentially abundant metabolites between seasons. Seasonal differences were recorded in metabolite content in all analyzed components suggesting that the decreased oocyte competence during NBS may be linked to alteration of several metabolic pathways. The pathway enrichment analysis revealed that differences in the metabolites between the seasons were linked to glutathione, energy generating and amino acid metabolism and phospholipid biosynthesis. The current work allows the identification of potential positive competence markers in the follicular fluid as glutathione, glutamate, lactate and choline, and negative markers like leucine, isoleucine and β-hydroxybutyrate. These results form a major basis to develop potential strategies to optimize the follicular environment and the IVM medium to improve the competence of oocytes during the NBS.
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Affiliation(s)
- Michal Andrzej Kosior
- Department of Veterinary Medicine and Animal Production - Federico II University, Via F. Delpino 1, 80137, Naples, Italy
| | - Riccardo Esposito
- Department of Veterinary Medicine and Animal Production - Federico II University, Via F. Delpino 1, 80137, Naples, Italy
| | - Natascia Cocchia
- Department of Veterinary Medicine and Animal Production - Federico II University, Via F. Delpino 1, 80137, Naples, Italy.
| | - Federica Piscopo
- Department of Veterinary Medicine and Animal Production - Federico II University, Via F. Delpino 1, 80137, Naples, Italy
| | - Valentina Longobardi
- Department of Veterinary Medicine and Animal Production - Federico II University, Via F. Delpino 1, 80137, Naples, Italy
| | - Nunzio Antonio Cacciola
- Department of Veterinary Medicine and Animal Production - Federico II University, Via F. Delpino 1, 80137, Naples, Italy
| | | | - Giuseppe Campanile
- Department of Veterinary Medicine and Animal Production - Federico II University, Via F. Delpino 1, 80137, Naples, Italy
| | - Hilde Aardema
- Department of Farm Animal Health, Faculty of Veterinary Medicine - Utrecht University, Yalelaan 7, 3584 CL, Utrecht, the Netherlands
| | - Bianca Gasparrini
- Department of Veterinary Medicine and Animal Production - Federico II University, Via F. Delpino 1, 80137, Naples, Italy
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Karasahin T, Alkan H, Satilmis F, Dursun S, Ozturk C, Bulut G, Aksoy NH, Tekindal MA, Caglayan T, Yesilkaya OF, Erdem H. Relationship between total antioxidant/oxidant status, and oxidative stress index and superovulation response in donor cows. Livest Sci 2021. [DOI: 10.1016/j.livsci.2020.104340] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Melatonin levels and microRNA (miRNA) relative expression profile in the follicular ambient microenvironment in patients undergoing in vitro fertilization process. J Assist Reprod Genet 2020; 38:443-459. [PMID: 33226531 DOI: 10.1007/s10815-020-02010-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Accepted: 11/09/2020] [Indexed: 02/08/2023] Open
Abstract
PURPOSE Intrafollicular fluid (IFF) melatonin plays a decisive role in maintaining granulosa cells' DNA integrity and protects them against apoptosis. It reduces oxidative stress and improves the oocyte quality with a higher fertilization rate. METHOD This prospective study investigated the antioxidant property of IFF melatonin and its impact on IVF outcome parameters. We also explored the relative expression of five microRNAs (miR-663b, miR-320a, miR-766-3p, miR-132-3p, miR-16-5p) and levels of cell-free DNA (cfDNA) by real-time PCR in unexplained infertile patients. We collected 425 follicular fluid (FF) samples containing mature oocytes from 295 patients undergoing IVF. RESULTS Patients were subgrouped based on IFF melatonin concentration (group A ≤ 30 pg/mL, group B > 70 to ≤ 110 pg/mL, group C > 111 to ≤ 385 pg/mL). Our results showed that patients with ≤ 30 pg/mL IFF melatonin levels have significantly higher oxidative stress markers, cfDNA levels, and lower relative expression of miR-663b, miR-320a, miR-766-3p, miR-132-3p, and miR-16-5p compared to other subgroups (p < 0.001). Similarly, they have a low fertilization rate and a reduced number of high-quality day 3 embryos. CONCLUSION Findings suggest that the therapeutic use of melatonin produces a considerable rise in the number of mature oocytes retrieved, fertilization rate, and good-quality embryo selection. Furthermore, miRNA signature enhances the quality of embryo selection, thus, may allow us to classify them as non-invasive biomarkers to identify good-quality embryos.
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Growth hormone alleviates oxidative stress and improves oocyte quality in Chinese women with polycystic ovary syndrome: a randomized controlled trial. Sci Rep 2020; 10:18769. [PMID: 33127971 PMCID: PMC7599233 DOI: 10.1038/s41598-020-75107-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Accepted: 10/07/2020] [Indexed: 12/18/2022] Open
Abstract
Oxidative stress (OS) is associated with poor oocyte quality and in vitro fertilization and embryo transfer (IVF-ET) outcomes for patients with polycystic ovary syndrome (PCOS). Growth hormone (GH) can function to reduce OS in some types of cells. Therefore, this prospective randomized study investigated whether GH can significantly improve OS and oocyte quality in women with PCOS. This study enrolled 109 and 50 patients with and without PCOS (controls), respectively. The patients with PCOS were randomly assigned to receive treatment with GH (PCOS-T) or not (PCOS-C). The primary outcome included markers of OS in serum and FF, and secondary outcomes were mitochondrial function in granulosa cells (GCs) and IVF-ET outcomes. The PCOS groups showed higher basal serum total oxidant status (TOS) and OS index (OSI) levels. The follicle fluid (FF) TOS and OSI and GC apoptosis rate were significantly higher, whereas the GC mitochondrial membrane potential (MMP) was significantly lower in the PCOS-C group than in the PCOS-T and non-PCOS control groups (P < 0.05). Significantly more oocytes were fertilised and cleavage stage embryos were produced in the PCOS-T group than in the PCOS-C group (P < 0.05). GH also improved the rates of implantation and clinical pregnancy, but not significantly (P > 0.05). This study showed that GH alleviated the TOS and OSI level in FF and improved GC mitochondrial dysfunction and oocyte quality in patients with PCOS. Clinical Trial Registration Number: This project was prospectively registered on the Chinese Clinical Trial Registry on October 20, 2018. (ChiCTR1800019437) (https://www.chictr.org.cn/edit.aspx?pid=28663&htm=4).
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Gong Y, Zhang K, Xiong D, Wei J, Tan H, Qin S. Growth hormone alleviates oxidative stress and improves the IVF outcomes of poor ovarian responders: a randomized controlled trial. Reprod Biol Endocrinol 2020; 18:91. [PMID: 32891163 PMCID: PMC7487463 DOI: 10.1186/s12958-020-00648-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Accepted: 08/27/2020] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Oxidative stress (OS), defined as an imbalance between excessive reactive oxygen species (ROS) and/or reactive nitrogen species (RNS) production and antioxidant insufficiency, has been suggested to be involved in the pathogenesis of poor ovarian response (POR). Growth hormone (GH) can reduce OS in some cell types. This study investigated whether GH can improve OS and the in vitro fertilization and embryo transfer (IVF-ET) outcomes of poor ovarian responders. METHODS This study enrolled 105 patients with POR and 58 patients without POR (controls) who were diagnosed according to the Bologna criteria and underwent conventional IVF-ET. Poor ovarian responders were randomly assigned to two groups: the POR-GH group, which received pretreatment with GH 4 IU/d on day 2 of the previous menstrual cycle before IVF until the trigger day, and the POR-C group, which received no pretreatment. OS markers in follicular fluid (FF), ROS levels in granulosa cells (GCs), and the IVF outcomes of the groups were compared. RESULTS Endometrial thickness on trigger day, the number of cleaved embryos, the number of higher-quality embryos, and the rates of embryo formation, higher-quality embryo formation, implantation and clinical pregnancy were significantly increased in the POR-GH group compared with the POR-C group (P < 0.05). Moreover, compared to those in the non-POR group, FF malondialdehyde (MDA), total oxidant status (TOS), oxidative stress index (OSI) and ROS levels in GCs were significantly higher, whereas superoxide dismutase (SOD) and the total antioxidant capacity (TAC) were significantly lower in the POR-C group (P < 0.05). Furthermore, compared with those in the POR-C group, the FF TAC was significantly increased in the POR-GH group, and TOS, OSI and intracellular ROS levels were significantly reduced (P < 0.05). CONCLUSIONS Pretreatment with GH alleviates OS and improves oocyte quality and IVF outcomes of poor ovarian responders. TRIAL REGISTRATION Chinese Clinical Trial Registry. ChiCTR1900021269 . Registered 8 February 2019, http://www.chictr.org.cn/edit.aspx?pid=35837&htm=4 .
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Affiliation(s)
- Yan Gong
- Reproductive Medicine Centre, Sichuan Provincial Women's and Children's Hospital, The Affiliated Women's and children's Hospital of Chengdu Medical College, #290 Shayan West Second Street, Wuhou District, Chengdu, Sichuan, People's Republic of China.
| | - Kun Zhang
- Department of Genetics, School of Bioscience and Technology, Chengdu Medical College, #783 Xindu Avenue, Xindu District, Chengdu, Sichuan, 610500, People's Republic of China.
| | - Dongsheng Xiong
- Reproductive Medicine Centre, Sichuan Provincial Women's and Children's Hospital, The Affiliated Women's and children's Hospital of Chengdu Medical College, #290 Shayan West Second Street, Wuhou District, Chengdu, Sichuan, People's Republic of China
| | - Jiajing Wei
- Reproductive Medicine Centre, Sichuan Provincial Women's and Children's Hospital, The Affiliated Women's and children's Hospital of Chengdu Medical College, #290 Shayan West Second Street, Wuhou District, Chengdu, Sichuan, People's Republic of China
| | - Hao Tan
- Department of Genetics, School of Bioscience and Technology, Chengdu Medical College, #783 Xindu Avenue, Xindu District, Chengdu, Sichuan, 610500, People's Republic of China
| | - Shengfang Qin
- Department of Medical Genetics and Prenatal Diagnosis, Sichuan Provincial Women's and Children's Hospital, The Affiliated Women's and children's Hospital of Chengdu Medical College, Chengdu, Sichuan, People's Republic of China
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Rahiminejad ME, Moaddab A, Ganji M, Eskandari N, Yepez M, Rabiee S, Wise M, Ruano R, Ranjbar A. Oxidative stress biomarkers in endometrial secretions: A comparison between successful and unsuccessful in vitro fertilization cycles. J Reprod Immunol 2016; 116:70-5. [PMID: 27232354 DOI: 10.1016/j.jri.2016.05.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Revised: 04/28/2016] [Accepted: 05/10/2016] [Indexed: 01/11/2023]
Abstract
A potential role of oxidative stress has been implicated in the outcome of various steps of assisted reproductive technology (ART). In a prospective cohort study, a total of 100 patients undergoing IVF/ICSI procedure due to male factor infertility were recruited based on the inclusion criteria. In all patients, 1-2ml of endometrial secretions was aspirated prior to embryo transfer. The oxidative stress markers in endometrial secretions, including superoxide dismutase (SOD), catalase (CAT) activities, lipid peroxidation (LPO), total thiol groups (TTG), and total antioxidant power (TAP) were investigated and compared among study groups including term pregnancy, failed IVF cycle, and miscarriage. P<0.05 was considered statistically different. Of the 100 patients, 28 cases (28%) resulted in ongoing pregnancy (biochemical pregnancy followed by clinical pregnancy), 11 cases (11%) resulted in miscarriage, and 61 cases (61%), resulted in failed IVF cycle. SOD, LPO, CAT, and TAP levels in the endometrial secretions of the three groups were statistically different (P-value <0.01, <0.001, <0.001, and <0.001, respectively). TTG levels in endometrial secretion of three groups were not statistically different (P-value=0.837). Our results indicated that higher levels of antioxidants such as SOD, CAT, or TAP, and lower levels of oxidative stress markers such as LPO in the endometrial secretions were associated with successful IVF outcome.
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Affiliation(s)
| | - Amirhossein Moaddab
- Department of Obstetrics and Gynecology, Baylor College of Medicine, Houston, TX, USA.
| | - Maziar Ganji
- Students' Research Committee, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Nika Eskandari
- Students' Research Committee, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Mayel Yepez
- Department of Obstetrics and Gynecology, Baylor College of Medicine, Houston, TX, USA
| | - Soghra Rabiee
- Department of Obstetrics and Gynecology, Fatemieh Women's Hospital, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Meredith Wise
- Department of Obstetrics and Gynecology, Baylor College of Medicine, Houston, TX, USA
| | - Rodrigo Ruano
- Department of Obstetrics and Gynecology, Baylor College of Medicine, Houston, TX, USA
| | - Akram Ranjbar
- Department of Toxicology and Pharmacology, School of Pharmacy, Hamadan University of Medical Sciences, Hamadan, Iran
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Yilmaz N, Inal HA, Gorkem U, Sargin Oruc A, Yilmaz S, Turkkani A. Follicular fluid total antioxidant capacity levels in PCOS. J OBSTET GYNAECOL 2016; 36:654-7. [PMID: 26911305 DOI: 10.3109/01443615.2016.1148683] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
In this study, our aim was to assess total antioxidant capacity (TAC) levels in follicular fluid (FF) and their relationship to clinical pregnancy rates in PCOS patients undergoing assisted reproduction (ART). Twenty-two women with polycystic ovary syndrome (PCOS) (Group 1) and 41 women without PCOS (Group 2) were included in this study. Clinical and laboratory parameters and FF TAC levels were investigated. No statistically significant differences were found between the groups with regard to age and baseline parameters. Although we could not demonstrate a significant difference in FF TAC levels between the two groups (p=0.469), there was a significant positive correlation between FF TAC and clinical pregnancy rates, BMI, and the duration of infertility for the entire group (r=0.254, p=0.048; r=0.312, p=0.013; r=0.259, p=0.040; respectively). Owing to the correlation between FF TAC and the clinical pregnancy rates, further studies evaluating the impact of FF TAC levels on ART outcomes in patients with PCOS and other etiologies of infertility are needed.
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Affiliation(s)
- Nafiye Yilmaz
- a Dr. Zekai Tahir Burak Women's Health Education and Research Hospital , Ankara , Turkey
| | - Hasan Ali Inal
- b Konya Education and Research Hospital , Konya , Turkey , and
| | - Umit Gorkem
- c Department of IVF Unit, Faculty of Medicine, Hitit University , Corum , Turkey
| | - Ayla Sargin Oruc
- a Dr. Zekai Tahir Burak Women's Health Education and Research Hospital , Ankara , Turkey
| | - Saynur Yilmaz
- a Dr. Zekai Tahir Burak Women's Health Education and Research Hospital , Ankara , Turkey
| | - Ayten Turkkani
- a Dr. Zekai Tahir Burak Women's Health Education and Research Hospital , Ankara , Turkey
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Relationship between oxidative stress and clinical pregnancy in assisted reproductive technology treatment cycles. J Assist Reprod Genet 2013; 30:765-72. [PMID: 23666546 PMCID: PMC3696458 DOI: 10.1007/s10815-013-0005-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2013] [Accepted: 04/22/2013] [Indexed: 11/17/2022] Open
Abstract
Purpose To examine the relationship between serum total oxidant (TOS) and antioxidant (TAS) levels and clinical pregnancy in assisted reproductive technology (ART) cycles. Methods Prior to and after oocyte pick-up (OPU) and embryo transfer (ET), blood samples were collected from gynecologically normal females (n = 70) who were enrolled for ART solely due to male factor infertility. TAS, TOS levels and oxidative stress indexes (OSI: TOS/TAS) in four phases of treatment cycle (pre and post OPU and ET) between clinically pregnant and non-pregnant patients were compared. Critical cut-off values of significantly different TAS, TOS levels and OSIes for clinical pregnancy were established. Results The TAS levels in patients with clinical pregnancy were significantly higher in all of the four phases of the cycle. Post-OPU and pre-ET TOS levels were significantly higher in clinically pregnant patients. According to OSIes; only the pre-OPU OSI was significantly lower in clinically pregnant patients compared with non-pregnant ones. Moreover, the highest area under the ROC curve (AUC) from the seven different significant measurements [1) pre-OPU OSI, 2) pre-OPU TAS, 3) post-OPU TAS, 4) pre-ET TAS, 5) post-ET TAS, 6) post-OPU TOS, 7) pre-ET TOS] was related to pre-OPU OSI. Conclusions In ART cycles, women with a higher total antioxidant status prior to and after OPU and prior to and after ET have an increased probability of clinical pregnancy. Additionally; OSI before OPU was one of the most important determinants for clinical pregnancy, so the oxidant and antioxidant balance is as important as the antioxidant concentration alone.
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Eichenlaub-Ritter U, Wieczorek M, Lüke S, Seidel T. Age related changes in mitochondrial function and new approaches to study redox regulation in mammalian oocytes in response to age or maturation conditions. Mitochondrion 2010; 11:783-96. [PMID: 20817047 DOI: 10.1016/j.mito.2010.08.011] [Citation(s) in RCA: 145] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2010] [Accepted: 08/26/2010] [Indexed: 12/26/2022]
Abstract
Mammalian oocytes are long-lived cells in the human body. They initiate meiosis already in the embryonic ovary, arrest meiotically for long periods in dictyate stage, and resume meiosis only after extensive growth and a surge of luteinizing hormone which mediates signaling events that overcome meiotic arrest. Few mitochondria are initially present in the primordial germ cells while there are mitogenesis and structural and functional differentiation and stage-specific formation of functionally diverse domains of mitochondria during oogenesis. Mitochondria are most prominent cell organelles in oocytes and their activities appear essential for normal spindle formation and chromosome segregation, and they are one of the most important maternal contributions to early embryogenesis. Dysfunctional mitochondria are discussed as major factor in predisposition to chromosomal nondisjunction during first and second meiotic division and mitotic errors in embryos, and in reduced quality and developmental potential of aged oocytes and embryos. Several lines of evidence suggest that damage by oxidative stress/reactive oxygen species in dependence of age, altered antioxidative defence and/or altered environment and bi-directional signaling between oocyte and the somatic cells in the follicle contribute to reduced quality of oocytes and blocked or aberrant development of embryos after fertilization. The review provides an overview of mitogenesis during oogenesis and some recent data on oxidative defence systems in mammalian oocytes, and on age-related changes as well as novel approaches to study redox regulation in mitochondria and ooplasm. The latter may provide new insights into age-, environment- and cryopreservation-induced stress and mitochondrial dysfunction in oocytes and embryos.
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Affiliation(s)
- U Eichenlaub-Ritter
- University of Bielefeld, Faculty of Biology, Gene Technology/Microbiology, Bielefeld, Germany.
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