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Mayeur A, Magnan F, Mathieu S, Rubens P, Sperelakis Beedham B, Sonigo C, Steffann J, Frydman N. What importance do donors and recipients attribute to the nuclear DNA-related genetic heritage of oocyte donation? Hum Reprod 2024; 39:770-778. [PMID: 38420661 DOI: 10.1093/humrep/deae030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Revised: 01/31/2024] [Indexed: 03/02/2024] Open
Abstract
STUDY QUESTION How do oocyte donors and recipients perceive the genetic link related to the transfer of nuclear DNA between donors and offspring? SUMMARY ANSWER Whether they are donors or recipients, individuals attach great importance to the transmission of their genetic heritage, since 94.5% would opt for the pronuclear transfer method to preserve this genetic link in the context of oocyte donation. WHAT IS KNOWN ALREADY Since 1983, the use of oocyte donation has increased worldwide. Performed in France since the late 1980s and initially offered to women with premature ovarian insufficiency, its indications have progressively expanded and now it is proposed in many indications to prevent the transmission of genetically inherited diseases. This has resulted in an increase in the waiting time for access to oocyte donation due to the difficulty in recruiting oocyte donors in French ART centres. Several articles have discussed how to fairly distribute donor oocytes to couples, but few have interviewed women in the general population to record their feelings about oocyte donation, as either the donor or recipient and the importance given to the genetic link between the oocyte donors and the children born. Mitochondrial replacement therapy (MRT) is a technique originally developed for women at risk of transmitting a mitochondrial DNA mutation. Recently, MRT has been considered for embryo arrest and oocyte rejuvenation as it could help females to reproduce with their own genetic material through the transfer of their oocyte nucleus into a healthy donor oocyte cytoplasm. STUDY DESIGN, SIZE, DURATION We conducted an opinion survey from January 2021 to December 2021, during which 1956 women completed the questionnaire. Thirteen participants were excluded from the analysis due to incomplete responses to all the questions. Consequently, 1943 women were included in the study. PARTICIPANTS/MATERIALS, SETTING, METHODS We specifically developed a questionnaire for this study, which was created and distributed using the Drag'n Survey® software. The questionnaire consisted of 21 items presented alongside a video created with whiteboard animation software. The aim was to analyse whether certain factors, such as age, education level, marital status, number of children, use of ART for pregnancy, video viewing, and knowledge about oocyte donation, were associated with feelings towards oocyte donation, by using a univariate conditional logistic regression model. This statistical method was also used to assess whether women would be more inclined to consider oocyte donation with the pronuclear transfer technique rather than the whole oocyte donation. All parameters found to be statistically significant in the univariate analysis were subsequently tested in a multivariate model using logistic regression. MAIN RESULTS AND THE ROLE OF CHANCE Most women were concerned about the biological genetic contribution of the donated oocyte (94.8%). The most common reason for a women's reluctance to donate their oocytes was their unwillingness to pass on their genetic material (33.3%). Nearly 70% of women who were initially hesitant to donate their oocytes indicated that they would reconsider their decision if the oocyte donation was conducted using donated cytoplasm and the pronuclear transfer technique. Concomitantly, >75% of the respondents mentioned that it would be easier to receive a cytoplasm donation. The largest proportion of the population surveyed (94.5%) expressed their support for its legalization. LIMITATIONS, REASONS FOR CAUTION In this study, a substantial portion of the responses came from individuals with medical or paramedical backgrounds, potentially introducing a recruitment bias among potential donors. The rate of missing responses to the question regarding the desire to become an oocyte donor was 13.6%, while the question about becoming an oocyte cytoplasm donor had a missing response rate of 23%. These missing responses may introduce a bias in the interpretation of the data. WIDER IMPLICATIONS OF THE FINDINGS This study was the first to demonstrate that, for the French population studied, the combination of oocyte cytoplasm donation with pronuclear transfer could offer a promising approach to enhance the acceptance of oocyte donation for both the donor and the recipient. STUDY FUNDING/COMPETING INTEREST(S) No external funding was used for this study. The authors have no conflicts of interest. TRIAL REGISTRATION NUMBER N/A.
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Affiliation(s)
- A Mayeur
- Service de Biologie de la Reproduction-CECOS, Assistance Publique Hôpitaux de Paris, Hôpital Antoine Béclère, Clamart, France
- Université de Paris Sud, Université Paris-Saclay, Le Kremlin-Bicêtre, France
| | - F Magnan
- Service de Biologie de la Reproduction-CECOS, Assistance Publique Hôpitaux de Paris, Hôpital Antoine Béclère, Clamart, France
| | - S Mathieu
- École Pratique des Hautes Études (EPHE), Paris Sciences Lettres (PSL), GSRL UMR8582, Paris, France
| | - P Rubens
- Service de Médecine Génomique des Maladies rares, Assistance Publique Hôpitaux de Paris, Groupe Hospitalier Necker-Enfants Malades, Paris, France
- Université Paris Cité, Institut Imagine, INSERM UMR1163, Paris, France
| | - B Sperelakis Beedham
- Service de Médecine Génomique des Maladies rares, Assistance Publique Hôpitaux de Paris, Groupe Hospitalier Necker-Enfants Malades, Paris, France
| | - C Sonigo
- Assistance Publique-Hôpitaux de Paris (APHP), Université Paris Saclay, Service de Médecine de la Reproduction et Préservation de la Fertilité, Hôpital Antoine Béclère, Clamart, France
- France Université Paris Saclay, Inserm, Physiologie et physiopathologie endocrinienne, Le Kremlin-Bicêtre, France
| | - J Steffann
- Service de Médecine Génomique des Maladies rares, Assistance Publique Hôpitaux de Paris, Groupe Hospitalier Necker-Enfants Malades, Paris, France
- Université Paris Cité, Institut Imagine, INSERM UMR1163, Paris, France
| | - N Frydman
- Service de Biologie de la Reproduction-CECOS, Assistance Publique Hôpitaux de Paris, Hôpital Antoine Béclère, Clamart, France
- Université de Paris Sud, Université Paris-Saclay, Le Kremlin-Bicêtre, France
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Huber HF, Nathanielsz PW, Clarke GD. Summary and Assessment of Studies on Cardiac Aging in Nonhuman Primates. Comp Med 2021; 71:460-465. [PMID: 34711301 PMCID: PMC8715764 DOI: 10.30802/aalas-cm-21-000038] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 05/02/2021] [Accepted: 06/14/2021] [Indexed: 11/05/2022]
Abstract
Nonhuman primates (NHP) are important translational models for cardiac aging. To assess progress in this research area and to provide a reference for other investigators, we identified papers indexed in PubMed to determine what species, ages, outcomes, treatments, and approaches have been studied. Since 1983, 33 studies of cardiac aging in NHP have been published. Of these, 27 used species of macaque, 6 baboon, 1 vervet, 1 orangutan, and 1 marmoset (some studies were multispecies). Common research approaches were echocardiography, ECG, and histology of the left ventricle. Only 10 studies performed sex-based analyses. The average age of the oldest macaque studied was 26 y. The reported mean lifespan of macaques in captivity is around 30 y. The age of the oldest baboon studied was 24 y. Baboons in captivity are reported to live on average to 21 y. Twelve studies took a "life course" approach, studying animals of a wide range of ages from less than or equal to 10 y through the late teens to thirties, and employing analyses designed to show change over time. Keeping NHP into old age is a major challenge for biomedical research. The ideal design is to start monitoring in early life and to track how cardiac structure and function change with age. Important issues for future research are an increased focus on life-course approaches, investment in existing life-course NHP cohorts, better reporting of study sample characteristics, more molecular studies to identify genetic risk factors and mechanisms, attention to sex as a biological variable, a move away from descriptive reports to mechanistic studies, development of biomarkers to predict disease risk, and exploration of interventions that are implemented early in life to prevent or delay age-related disease later in life. Reducing exposure to early life adversity, identifying early-life biomarkers of aging and age-related disease, and early treatment can contribute to longer health span.
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Affiliation(s)
- Hillary F Huber
- Department of Animal Science, University of Wyoming, Laramie, Wyoming; Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, Texas;,
| | - Peter W Nathanielsz
- Department of Animal Science, University of Wyoming, Laramie, Wyoming; Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, Texas
| | - Geoffrey D Clarke
- Department of Radiology, University of Texas Health Science Center, San Antonio, Texas ‡Institution at which work was performed: Southwest National Primate Research Center, San Antonio, Texas
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3
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Simard ML, Mourier A, Greaves LC, Taylor RW, Stewart JB. A novel histochemistry assay to assess and quantify focal cytochrome c oxidase deficiency. J Pathol 2018; 245:311-323. [PMID: 29660116 PMCID: PMC6032845 DOI: 10.1002/path.5084] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Revised: 03/12/2018] [Accepted: 04/05/2018] [Indexed: 01/25/2023]
Abstract
Defects in the respiratory chain, interfering with energy production in the cell, are major underlying causes of mitochondrial diseases. In spite of this, the surprising variety of clinical symptoms, disparity between ages of onset, as well as the involvement of mitochondrial impairment in ageing and age‐related diseases continue to challenge our understanding of the pathogenic processes. This complexity can be in part attributed to the unique metabolic needs of organs or of various cell types. In this view, it remains essential to investigate mitochondrial dysfunction at the cellular level. For this purpose, we developed a novel enzyme histochemical method that enables precise quantification in fresh‐frozen tissues using competing redox reactions which ultimately lead to the reduction of tetrazolium salts and formazan deposition in cytochrome c oxidase‐deficient mitochondria. We demonstrate that the loss of oxidative activity is detected at very low levels – this achievement is unequalled by previous techniques and opens up new opportunities for the study of early disease processes or comparative investigations. Moreover, human biopsy samples of mitochondrial disease patients of diverse genotypic origins were used and the successful detection of COX‐deficient cells suggests a broad application for this new method. Lastly, the assay can be adapted to a wide range of tissues in the mouse and extends to other animal models, which we show here with the fruit fly, Drosophila melanogaster. Overall, the new assay provides the means to quantify and map, on a cell‐by‐cell basis, the full extent of COX deficiency in tissues, thereby expending new possibilities for future investigation. © 2018 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.
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Affiliation(s)
| | - Arnaud Mourier
- Max Planck Institute for Biology of Ageing, Cologne, Germany.,CNRS, Université de Bordeaux, Institut de Biochimie et Génétique Cellulaires, UMR5095, Bordeaux, France
| | - Laura C Greaves
- Newcastle University LLHW Centre for Ageing and Vitality, Newcastle University, Newcastle upon Tyne, UK.,Wellcome Centre for Mitochondrial Research, Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, UK
| | - Robert W Taylor
- Wellcome Centre for Mitochondrial Research, Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, UK.,NHS Highly Specialised Mitochondrial Diagnostic Laboratory, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - James B Stewart
- Max Planck Institute for Biology of Ageing, Cologne, Germany
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4
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Klichko V, Sohal BH, Radyuk SN, Orr WC, Sohal RS. Decrease in cytochrome c oxidase reserve capacity diminishes robustness of Drosophila melanogaster and shortens lifespan. Biochem J 2014; 459:127-35. [PMID: 24444354 DOI: 10.1042/bj20131370] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The phenotypic effects of under- and over-expression of CcO (cytochrome c oxidase) regulatory subunits IV and Vb were examined in Drosophila melanogaster in order to test further the hypothesis that suppression of the activities of mitochondrial ETC (electron-transport chain) oxidoreductases retards the aging process and extends lifespan. Underexpression of both CcO subunits, induced by RNAi, resulted in decreases in the respective mRNA and protein levels, CcO holoenzyme activity, rate of mitochondrial respiration, walking speed and the lifespan of fruitflies. Overexpression of CcO IV or Vb in young fruitflies increased the amount of mRNA, but had no effect on the protein level or CcO catalytic activity. On the other hand, in older fruitflies, overexpression of CcO Vb, but not CcO IV, elevated the mRNA and protein amounts as well as the CcO holoenzyme activity, thereby preventing the typical age-related decline in CcO activity. Nevertheless, lifespans of the fruitflies overexpressing CcO IV or Vb were neither extended nor shortened. Our results demonstrate that: (i) the suppression of CcO function exerts deleterious rather than benign effects on fitness and survival, and (ii) the structure/function of CcO, an ETC oxidoreductase, can be 're-engineered' in vivo.
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Affiliation(s)
- Vladimir Klichko
- *Department of Biological Sciences, Southern Methodist University, Dallas, TX 75275, U.S.A
| | - Barbara H Sohal
- †Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, Los Angeles, CA 90089, U.S.A
| | - Svetlana N Radyuk
- *Department of Biological Sciences, Southern Methodist University, Dallas, TX 75275, U.S.A
| | - William C Orr
- *Department of Biological Sciences, Southern Methodist University, Dallas, TX 75275, U.S.A
| | - Rajindar S Sohal
- †Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, Los Angeles, CA 90089, U.S.A
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Chronic aerobic exercise training attenuates aortic stiffening and endothelial dysfunction through preserving aortic mitochondrial function in aged rats. Exp Gerontol 2014; 56:37-44. [PMID: 24607516 DOI: 10.1016/j.exger.2014.02.014] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Revised: 02/22/2014] [Accepted: 02/24/2014] [Indexed: 01/22/2023]
Abstract
Aging leads to large vessel arterial stiffening and endothelial dysfunction, which are important determinants of cardiovascular risk. The aim of present work was to assess the effects of chronic aerobic exercise training on aortic stiffening and endothelial dysfunction in aged rats and investigate the underlying mechanism about mitochondrial function. Chronic aerobic exercise training attenuated aortic stiffening with age marked by reduced collagen concentration, increased elastin concentration and reduced pulse wave velocity (PWV), and prevented aging-related endothelial dysfunction marked by improved endothelium-mediated vascular relaxation of aortas in response to acetylcholine. Chronic aerobic exercise training abated oxidative stress and nitrosative stress in aortas of aged rats. More importantly, we found that chronic aerobic exercise training in old rats preserved aortic mitochondrial function marked by reduced reactive oxygen species (ROS) formation and mitochondrial swelling, increased ATP formation and mitochondrial DNA content, and restored activities of complexes I and III and electron-coupling capacity between complexes I and III and between complexes II and III. In addition, it was found that chronic aerobic exercise training in old rats enhanced protein expression of uncoupling protein 2 (UCP-2), peroxisome proliferator-activated receptor γ co-activator 1α (PGC-1α), manganese superoxide dismutase (Mn-SOD), aldehyde dehydrogenase 2 (ALDH-2), prohibitin (PHB) and AMP-activated kinase (AMPK) phosphorylation in aortas. In conclusion, chronic aerobic exercise training preserved mitochondrial function in aortas, which, at least in part, explained the aorta-protecting effects of exercise training in aging.
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Gómez LA, Hagen TM. Age-related decline in mitochondrial bioenergetics: does supercomplex destabilization determine lower oxidative capacity and higher superoxide production? Semin Cell Dev Biol 2012; 23:758-67. [PMID: 22521482 DOI: 10.1016/j.semcdb.2012.04.002] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2012] [Revised: 03/31/2012] [Accepted: 04/04/2012] [Indexed: 12/17/2022]
Abstract
Mitochondrial decay plays a central role in the aging process. Although certainly multifactorial in nature, defective operation of the electron transport chain (ETC) constitutes a key mechanism involved in the age-associated loss of mitochondrial energy metabolism. Primarily, mitochondrial dysfunction affects the aging animal by limiting bioenergetic reserve capacity and/or increasing oxidative stress via enhanced electron leakage from the ETC. Even though the important aging characteristics of mitochondrial decay are known, the molecular events underlying inefficient electron flux that ultimately leads to higher superoxide appearance and impaired respiration are not completely understood. This review focuses on the potential role(s) that age-associated destabilization of the macromolecular organization of the ETC (i.e. supercomplexes) may be important for development of the mitochondrial aging phenotype, particularly in post-mitotic tissues.
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Affiliation(s)
- Luis A Gómez
- Linus Pauling Institute, Oregon State University, Corvallis, OR 97331, USA
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Castro MDR, Suarez E, Kraiselburd E, Isidro A, Paz J, Ferder L, Ayala-Torres S. Aging increases mitochondrial DNA damage and oxidative stress in liver of rhesus monkeys. Exp Gerontol 2011; 47:29-37. [PMID: 22027539 DOI: 10.1016/j.exger.2011.10.002] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2011] [Revised: 08/24/2011] [Accepted: 10/04/2011] [Indexed: 12/22/2022]
Abstract
While the mechanisms of cellular aging remain controversial, a leading hypothesis is that mitochondrial oxidative stress and mitochondrial dysfunction play a critical role in this process. Here, we provide data in aging rhesus macaques supporting the hypothesis that increased oxidative stress is a major characteristic of aging and may be responsible for the age-associated increase in mitochondrial dysfunction. We measured mitochondrial DNA (mtDNA) damage by quantitative PCR in liver and peripheral blood mononuclear cells of young, middle age, and old monkeys and show that older monkeys have increases in the number of mtDNA lesions. There was a direct correlation between the amount of mtDNA lesions and age, supporting the role of mtDNA damage in the process of aging. Liver from older monkeys showed significant increases in lipid peroxidation, protein carbonylations and reduced antioxidant enzyme activity. Similarly, peripheral blood mononuclear cells from the middle age group showed increased levels in carbonylated proteins, indicative of high levels of oxidative stress. Together, these results suggest that the aging process is associated with defective mitochondria, where increased production of reactive oxygen species results in extensive damage at the mtDNA and protein levels. This study provides valuable data based on the rhesus macaque model further validating age-related mitochondrial functional decline with increasing age and suggesting that mtDNA damage might be a good biomarker of aging.
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Affiliation(s)
- María del R Castro
- Department of Pharmacology and Toxicology, University of Puerto Rico Medical Sciences Campus, San Juan, Puerto Rico
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8
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Tellis CM, Rosen C, Close JM, Horton M, Yaruss JS, Verdolini-Abbott K, Sciote JJ. Cytochrome c oxidase deficiency in human posterior cricoarytenoid muscle. J Voice 2011; 25:387-94. [PMID: 20685075 PMCID: PMC3917494 DOI: 10.1016/j.jvoice.2010.03.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2009] [Accepted: 03/09/2010] [Indexed: 01/18/2023]
Abstract
BACKGROUND Mitochondrial alterations occur in skeletal muscle fibers throughout the normal aging process, resulting from increased accumulation of reactive oxide species (ROS). These result in respiratory chain abnormalities, which decrease the oxidative capacity of muscle fibers, leading to decreased contractile force, sarcopenia, or fiber necrosis. Intrinsic laryngeal muscles are a cranial muscle group that possesses some distinctive genotypic, phenotypic, and physiologic properties. Their susceptibility to mitochondrial alterations resulting from biological processes that increase levels of oxidative stress may be one of these distinctive characteristics. OBJECTIVES The incidence of cytochrome c oxidase (COX) deficiency (COX(-)) was determined in human posterior cricoarytenoid (PCA) muscle when compared with the human thyrohyoid (TH) muscle, an extrinsic laryngeal muscle that served as "control" muscle. Ten PCA and 10 TH muscles were harvested postlaryngectomy from 10 subjects ranging in age from 55 to 86 years. Differences in COX(-) were compared within and between muscle types using tissue section staining and standard morphometric analysis. RESULTS AND CONCLUSIONS COX(-) fibers were identified in both the PCA and TH muscles. The PCA muscle had 10 times as may affected fibers as the TH muscle, with significant differences in COX(-) found between muscle type and fiber type (P=0.003). Almost all of this effect was the result of elevated levels of COX(-) in type I fibers from the PCA muscle (P=0.002) that showed a strong positive correlation with increased age. These results suggest that increased mitochondrial alterations may occur in the PCA muscle during normal aging.
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Affiliation(s)
- Cari M Tellis
- Speech-Language Pathology Department, Misericordia University, Dallas, Pennsylvania 18612, USA.
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9
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Cytochrome c oxidase loses catalytic activity and structural integrity during the aging process in Drosophila melanogaster. Biochem Biophys Res Commun 2010; 401:64-8. [PMID: 20833144 DOI: 10.1016/j.bbrc.2010.09.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2010] [Accepted: 09/06/2010] [Indexed: 11/21/2022]
Abstract
The hypothesis, that structural deterioration of cytochrome c oxidase (CcO) is a causal factor in the age-related decline in mitochondrial respiratory activity and an increase in H₂O₂ generation, was tested in Drosophila melanogaster. CcO activity and the levels of seven different nuclear DNA-encoded CcO subunits were determined at three different stages of adult life, namely, young-, middle-, and old-age. CcO activity declined progressively with age by 33%. Western blot analysis, using antibodies specific to Drosophila CcO subunits IV, Va, Vb, VIb, VIc, VIIc, and VIII, indicated that the abundance these polypeptides decreased, ranging from 11% to 40%, during aging. These and previous results suggest that CcO is a specific intra-mitochondrial site of age-related deterioration, which may have a broad impact on mitochondrial physiology.
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10
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Age-related changes of cell death pathways in rat extraocular muscle. Exp Gerontol 2009; 44:420-5. [PMID: 19341788 DOI: 10.1016/j.exger.2009.03.006] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2008] [Revised: 02/24/2009] [Accepted: 03/22/2009] [Indexed: 01/07/2023]
Abstract
Changes in the structure and function of aging non-locomotor muscles remains understudied, despite their importance for daily living. Extraocular muscles (EOMs) have a high incidence of age-related mitochondrial defects possibly because of the metabolic stress resulting from their fast and constant activity. Apoptosis and autophagy (type I and II cell death, respectively) are linked to defects in mitochondrial function and contribute to sarcopenia in hind limb muscles. Therefore, we hypothesized that apoptosis and autophagy are altered with age in the EOMs. Muscles from 6-, 18-, and 30-month-old male Fisher 344-Brown Norway rats were used to investigate type I cell death, caspase-3, -8, -9, and -12 activity, and type II cell death. Apoptosis, as measured by TUNEL positive nuclei, and mono- and oligo-nucleosomal content, did not change with age. Similarly, caspase-3, -8, -9, and -12 activity was not affected by aging. By contrast, autophagy, as estimated by gene expression of Atg5 and Atg7, and protein abundance of LC3 was lower in EOMs of aged rats. Based on these data, we suggest that the decrease in autophagy with age leads to the accumulation of damaged organelles, particularly mitochondria, which results in the decrease in function observed in EOM with age.
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Navarro A, López-Cepero JM, Bández MJ, Sánchez-Pino MJ, Gómez C, Cadenas E, Boveris A. Hippocampal mitochondrial dysfunction in rat aging. Am J Physiol Regul Integr Comp Physiol 2007; 294:R501-9. [PMID: 18077512 DOI: 10.1152/ajpregu.00492.2007] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Hippocampus mitochondrial dysfunction with impaired electron transfer and increased oxidative damage was observed upon rat aging. Hippocampal mitochondria of aged (12 mo) and senescent (20 mo) rats showed, compared with young (4 mo) rats, marked decreases in the rate of state 3 respiration with NAD-dependent substrates (32-51%) and in the activities of mitochondrial complexes I (57-73%) and IV (33-54%). The activity of mitochondrial nitric oxide synthase was also decreased, 53-66%, with age. These losses in enzymatic activity were more marked in the hippocampus than in brain cortex or in whole brain. The histochemical assay of mitochondrial complex IV in the hippocampus showed decreased staining upon aging. Oxidative damage, determined as the mitochondrial content of thiobarbituric-acid reactive substances (TBARS) and protein carbonyls, increased in aged and senescent hippocampus (66-74% in TBARS and 48-96% in carbonyls). A significant statistical correlation was observed between mitochondrial oxidative damage and enzymatic activity. Mitochondrial dysfunction with shortage of energy supply is considered a likely cause of dysfunction in aged hippocampus.
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Affiliation(s)
- Ana Navarro
- Departamento de Bioquímica y Biología Molecular, Facultad de Medicina, Plaza Fragela 9, 11003-Cádiz, Spain.
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12
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The role of mitochondrial DNA mutations in aging and sarcopenia: implications for the mitochondrial vicious cycle theory of aging. Exp Gerontol 2007; 43:24-33. [PMID: 17997255 DOI: 10.1016/j.exger.2007.10.001] [Citation(s) in RCA: 170] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2007] [Revised: 09/28/2007] [Accepted: 10/01/2007] [Indexed: 01/07/2023]
Abstract
Aging is associated with a progressive loss of skeletal muscle mass and strength and the mechanisms mediating these effects likely involve mitochondrial DNA (mtDNA) mutations, mitochondrial dysfunction and the activation of mitochondrial-mediated apoptosis. Because the mitochondrial genome is densely packed and close to the main generator of reactive oxygen species (ROS) in the cell, the electron transport chain (ETC), an important role for mtDNA mutations in aging has been proposed. Point mutations and deletions in mtDNA accumulate with age in a wide variety of tissues in mammals, including humans, and often coincide with significant tissue dysfunction. Here, we examine the evidence supporting a causative role for mtDNA mutations in aging and sarcopenia. We review experimental outcomes showing that mtDNA mutations, leading to mitochondrial dysfunction and possibly apoptosis, are causal to the process of sarcopenia. Moreover, we critically discuss and dispute an important part of the mitochondrial 'vicious cycle' theory of aging which proposes that accumulation of mtDNA mutations may lead to an enhanced mitochondrial ROS production and ever increasing oxidative stress which ultimately leads to tissue deterioration and aging. Potential mechanism(s) by which mtDNA mutations may mediate their pathological consequences in skeletal muscle are also discussed.
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Chang J, Cornell JE, Van Remmen H, Hakala K, Ward WF, Richardson A. Effect of aging and caloric restriction on the mitochondrial proteome. J Gerontol A Biol Sci Med Sci 2007; 62:223-34. [PMID: 17389719 DOI: 10.1093/gerona/62.3.223] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The rat mitochondrial proteome was analyzed using two-dimensional polyacrylamide gel electrophoresis (2-D PAGE), and proteins altered by age or caloric restriction (CR) were identified using mass spectrometry. Of 2061 mitochondrial proteins analyzed in the three tissues, a significant change with age occurred in 25 liver proteins (19 increased, 6 decreased), 3 heart proteins (1 increased, 2 decreased), and 5 skeletal muscle proteins (all increased). CR prevented the age-related change in the level of one liver mitochondrial protein, altered the levels of four proteins (one increased, three decreased) from heart, and one protein (decreased) from skeletal muscle. Identification of the proteins that changed with age or CR revealed that they were varied among the three tissues, that is, not one mitochondrial protein was changed, in common, by age or CR in any tissue studied. Thus, the effect of age on the mitochondrial proteome appears to be tissue-specific, and CR has a minor effect on age-related protein changes.
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Affiliation(s)
- Jinsook Chang
- Department of Physiology, The University of Texas Health Science Center at San Antonio, San Antonio, TX 78229-3900, USA
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14
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Palaniappan AR, Dai A. Mitochondrial ageing and the beneficial role of alpha-lipoic acid. Neurochem Res 2007; 32:1552-8. [PMID: 17476591 DOI: 10.1007/s11064-007-9355-4] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2006] [Accepted: 04/11/2007] [Indexed: 12/01/2022]
Abstract
Oxidative damage has been implicated to be a major causative factor in the decline in physiological functions that occur during the ageing process. Mitochondria are known to be a rich source for the production of free radicals and, consequently, mitochondrial components are susceptible to lipid peroxidation (LPO) that decreases respiratory activity. In the present investigation, we have evaluated mitochondrial LPO, 8-oxo-dG, oxidized glutathione, reduced glutathione, ATP, lipoic acid, TCA cycle enzymes and electron transport chain (ETC) complex activities in the brain of young versus aged rats. In aged rats, the contents of LPO, oxidized glutathione and 8-oxo-dG were high whereas reduced glutathione, ATP, lipoic acid, TCA cycle enzymes and ETC complex activities were found to be low. Lipoic acid administration to aged rats reduced the levels of mitochondrial LPO, 8-oxo-dG and oxidized glutathione and enhanced reduced glutathione, ATP, lipoic acid and ETC complex activities. In young rats lipoic acid administration showed only minimal lowering the levels of LPO, 8-oxo-dG and oxidized glutathione and slight increase in the levels of reduced glutathione, ATP, lipoic acid, TCA cycle enzymes and ETC complex activities. These findings suggest that the dithiol, lipoic acid, provides protection against age-related oxidative damage in the mitochondria of aged rats.
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Affiliation(s)
- A R Palaniappan
- Department of Biochemistry, Yokohama City University, Maioka-cho 641-12, Yokohama 244-0813, Japan
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15
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Navarro A, Boveris A. The mitochondrial energy transduction system and the aging process. Am J Physiol Cell Physiol 2006; 292:C670-86. [PMID: 17020935 DOI: 10.1152/ajpcell.00213.2006] [Citation(s) in RCA: 476] [Impact Index Per Article: 26.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Aged mammalian tissues show a decreased capacity to produce ATP by oxidative phosphorylation due to dysfunctional mitochondria. The mitochondrial content of rat brain and liver is not reduced in aging and the impairment of mitochondrial function is due to decreased rates of electron transfer by the selectively diminished activities of complexes I and IV. Inner membrane H(+) impermeability and F(1)-ATP synthase activity are only slightly affected by aging. Dysfunctional mitochondria in aged rodents are characterized, besides decreased electron transfer and O(2) uptake, by an increased content of oxidation products of phospholipids, proteins and DNA, a decreased membrane potential, and increased size and fragility. Free radical-mediated oxidations are determining factors of mitochondrial dysfunction and turnover, cell apoptosis, tissue function, and lifespan. Inner membrane enzyme activities, such as those of complexes I and IV and mitochondrial nitric oxide synthase, decrease upon aging and afford aging markers. The activities of these three enzymes in mice brain are linearly correlated with neurological performance, as determined by the tightrope and the T-maze tests. The same enzymatic activities correlated positively with mice survival and negatively with the mitochondrial content of lipid and protein oxidation products. Conditions that increase survival, as vitamin E dietary supplementation, caloric restriction, high spontaneous neurological activity, and moderate physical exercise, ameliorate mitochondrial dysfunction in aged brain and liver. The pleiotropic signaling of mitochondrial H(2)O(2) and nitric oxide diffusion to the cytosol seems modified in aged animals and to contribute to the decreased mitochondrial biogenesis in old animals.
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Affiliation(s)
- Ana Navarro
- Departamento de Bioquímica y Biología Molecular, Facultad de Medicina, Plaza Fragela 9, 11003 Cádiz, Spain.
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16
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Abstract
Extraocular muscle is fundamentally distinct from other skeletal muscles. Here, we review the biological organization of the extraocular muscles with the intent of understanding this novel muscle group in the context of oculomotor system function. The specific objectives of this review are threefold. The first objective is to understand the anatomic arrangement of the extraocular muscles and their compartmental or layered organization in the context of a new concept of orbital mechanics, the active pulley hypothesis. The second objective is to present an integrated view of the morphologic, cellular, and molecular differences between extraocular and the more traditional skeletal muscles. The third objective is to relate recent data from functional and molecular biology studies to the established extraocular muscle fiber types. Developmental mechanisms that may be responsible for the divergence of the eye muscles from a skeletal muscle prototype also are considered. Taken together, a multidisciplinary understanding of extraocular muscle biology in health and disease provides insights into oculomotor system function and malfunction. Moreover, because the eye muscles are selectively involved or spared in a variety of neuromuscular diseases, knowledge of their biology may improve current pathogenic models of and treatments for devastating systemic diseases.
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Affiliation(s)
- Robert F Spencer
- Department of Anatomy, Medical College of Virginia, Richmond, VA 23298, USA
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17
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Savitha S, Sivarajan K, Haripriya D, Kokilavani V, Panneerselvam C. Efficacy of levo carnitine and alpha lipoic acid in ameliorating the decline in mitochondrial enzymes during aging. Clin Nutr 2005; 24:794-800. [PMID: 15919137 DOI: 10.1016/j.clnu.2005.04.005] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2005] [Accepted: 04/13/2005] [Indexed: 11/24/2022]
Abstract
BACKGROUND Mitochondria are central to energy production and are therefore fully integrated into the rest of the cell's physiological responses to stress. The age-related decline of capacity of each cell to manufacture energy (as ATP) is due to the progressive loss of structural integrity of mitochondria. It is apparent that as the body ages, the cells become less and less able to maintain threshold levels of cellular energy production. METHODS In the present study we have evaluated the efficacy of carnitine, a mitochondrial metabolite and lipoic acid, a potent antioxidant on the activities of the tri carboxylic acid (TCA) cycle enzymes like succinate dehydrogenase, malate dehydrogenase, alpha-ketoglutarate dehydrogenase, Isocitrate dehydrogenase and electron transport complex I-IV in young and aged heart mitochondria. RESULT We observed that there was an age-dependent decrement in the levels of the TCA cycle enzymes and electron transport chain complexes. Supplementation of carnitine (300 mg/kg bw/day) and lipoic acid (100 mg/kg bw/day) for 30 days brought the activities of these enzymes to almost near normal levels. CONCLUSION These findings suggest that the combination of these drugs raises the mitochondrial energy producing capabilities by reversing the age-associated decline in mitochondrial enzyme activities and thereby protecting mitochondria from aging.
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Affiliation(s)
- S Savitha
- Department of Medical Biochemistry, Dr. ALMPG. Institute of Basic Medical Science, University of Madras, Taramani, Chennai 600113, India.
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18
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Mitochondrial electron transport and aging in the heart. ACTA ACUST UNITED AC 2002. [DOI: 10.1016/s1566-3124(02)11032-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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Wanagat J, Wolff MR, Aiken JM. Age-associated changes in function, structure and mitochondrial genetic and enzymatic abnormalities in the Fischer 344 x Brown Norway F(1) hybrid rat heart. J Mol Cell Cardiol 2002; 34:17-28. [PMID: 11812161 DOI: 10.1006/jmcc.2001.1483] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We hypothesized that cardiac aging in the rat involves mitochondrial genetic damage and mitochondrial enzymatic dysfunction of individual cardiomyocytes as has been demonstrated previously only in primate myocardium. Myocardium from Fischer 344 x Brown Norway F(1)hybrid rats of ages 5, 18 and 36-38 months was examined for mitochondrial genetic and enzymatic abnormalities. In-vivo hemodynamic measurements revealed age-related changes of left ventricular function while histological evaluation demonstrated an increase in percent area fibrosis from 7%+/-5 in the 5-month-old hearts to 38%+/-2 in the subendocardium of the left ventricle of 38-month-old rats. Mitochondrial genomes lacking 8000 to 9000 bp of primary sequence were detected in tissue homogenates from right and left ventricular myocardium and the abundance of these deleted genomes increased with age. In-situ histochemical staining of serial cryomicrotome sections of myocardial tissue revealed individual cardiomyocytes displaying abnormal, primarily absent, activities of cytochrome c oxidase and succinate dehydrogenase. The area density of histochemically-abnormal cardiomyocytes increased from 0.05 per mm(2)to 0.3 per mm(2)between 5 and 36-38 months of age in the left ventricle, and they were localized primarily to the left ventricular subendocardium. The presence of age-related mitochondrial genetic and enzymatic abnormalities in the Fischer 344 x Brown Norway F(1)hybrid rat heart suggests the role of mitochondrial dysfunction, secondary to mtDNA mutations, in age-related cardiomyocyte loss and subsequent cardiac aging.
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Affiliation(s)
- Jonathan Wanagat
- Medical Scientist Training Program, Department of Animal Health and Biomedical Sciences, University of Wisconsin, Madison, WI 53706, USA
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20
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Abstract
Increasing evidence suggests an important role of oxidant-induced damage in the progress of senescent changes, providing support for the free radical theory of aging proposed by Harman in 1956. However, considering that biological organisms continuously renew their structures, it is not clear why oxidative damage should accumulate with age. No strong evidence has been provided in favor of the concept of aging as an accumulation of synthetic errors (e.g. Orgel's 'error-catastrophe' theory and the somatic mutation theory). Rather, we believe that the process of aging may derive from imperfect clearance of oxidatively damaged, relatively indigestible material, the accumulation of which further hinders cellular catabolic and anabolic functions. From this perspective, it might be predicted that: (i) suppression of oxidative damage would enhance longevity; (ii) accumulation of incompletely digested material (e.g. lipofuscin pigment) would interfere with cellular functions and increase probability of death; (iii) rejuvenation during reproduction is mainly provided by dilution of undigested material associated with intensive growth of the developing organism; and (iv) age-related damage starts to accumulate substantially when development is complete, and mainly affects postmitotic, cells and extracellular matrix, not proliferating cells. There is abundant support for all these predictions.
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Affiliation(s)
- A Terman
- Department of Neuroscience and Locomotion, Faculty of Health Sciences, Linköping University, Sweden.
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21
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Wanagat J, Cao Z, Pathare P, Aiken JM. Mitochondrial DNA deletion mutations colocalize with segmental electron transport system abnormalities, muscle fiber atrophy, fiber splitting, and oxidative damage in sarcopenia. FASEB J 2001; 15:322-32. [PMID: 11156948 DOI: 10.1096/fj.00-0320com] [Citation(s) in RCA: 306] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The in vivo cellular impact of age-associated mitochondrial DNA mutations is unknown. We hypothesized that mitochondrial DNA deletion mutations contribute to the fiber atrophy and loss that cause sarcopenia, the age-related decline of muscle mass and function. We examined 82,713 rectus femoris muscle fibers from Fischer 344 x Brown Norway F1 hybrid rats of ages 5, 18, and 38 months through 1000 microns by serial cryosectioning and histochemical staining for cytochrome c oxidase and succinate dehydrogenase. Between 5 and 38 months of age, the rectus femoris muscle in the hybrid rat demonstrated a 33% decrease in mass concomitant with a 30% decrease in total fibers at the muscle mid-belly. We observed significant increases in the number of mitochondrial abnormalities with age from 289 +/- 8 ETS abnormal fibers in the entire 5-month-old rectus femoris to 1094 +/- 126 in the 38-month-old as calculated from the volume density of these abnormalities. Segmental mitochondrial abnormalities contained mitochondrial DNA deletion mutations as revealed by laser capture microdissection and whole mitochondrial genome amplification. Muscle fibers harboring mitochondrial deletions often displayed atrophy, splitting and increased steady-state levels of oxidative nucleic damage. These data suggest a causal role for age-associated mitochondrial DNA deletion mutations in sarcopenia.
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MESH Headings
- Aging
- Animals
- Atrophy
- Base Sequence
- DNA Damage
- DNA, Mitochondrial/genetics
- Electron Transport
- Electron Transport Complex IV/metabolism
- Hybridization, Genetic
- Male
- Mitochondria, Muscle/genetics
- Mitochondria, Muscle/metabolism
- Muscle Development
- Muscle Fibers, Skeletal/pathology
- Muscle, Skeletal/growth & development
- Muscle, Skeletal/metabolism
- Muscle, Skeletal/pathology
- Muscular Diseases/genetics
- Muscular Diseases/metabolism
- Muscular Diseases/pathology
- Rats
- Rats, Inbred BN
- Rats, Inbred F344
- Sequence Deletion
- Succinate Dehydrogenase/metabolism
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Affiliation(s)
- J Wanagat
- Medical Scientist Training Program, University of Wisconsin Medical School, Madison, Wisconsin 53706, USA
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de GREY AUBREYD. Noncorrelation Between Maximum Life Span and Antioxidant Enzyme Levels Among Homeotherms: Implications for Retarding Human Aging. ACTA ACUST UNITED AC 2000. [DOI: 10.1089/rej.1.2000.3.25] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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23
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Lee CM, Lopez ME, Weindruch R, Aiken JM. Association of age-related mitochondrial abnormalities with skeletal muscle fiber atrophy. Free Radic Biol Med 1998; 25:964-72. [PMID: 9840742 DOI: 10.1016/s0891-5849(98)00185-3] [Citation(s) in RCA: 94] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The hypothesis that mitochondrial dysfunction contributes to the senescent loss of skeletal muscle was investigated in quadriceps from 2- to 39-year old rhesus monkeys. Histological approaches, both cross-sectional (a single cross-section of the muscle) and longitudinal (multiple cross-sections of individual fibers spanning a 350-1600 microm region), were used to identify muscle fibers with abnormal mitochondrial electron transport system (ETS) enzyme activities and mitochondrial DNA deletions. Fibers were examined for two ETS activities, succinate dehydrogenase (SDH, ETS complex II) and cytochrome c oxidase (COX, ETS complex IV). The number of individual fibers containing ETS abnormalities (predominately negative for cytochrome c oxidase activity and/or hyperreactive for succinate dehydrogenase) increased with age. Deletions of the mitochondrial genome were observed in 89% of these ETS abnormal fibers. Longitudinal analysis allowed characterization of the ETS abnormal phenotype along their length. A decrease in cross-sectional area in 14% of the ETS abnormal fibers supports the hypothesis that deleted mitochondrial genomes may contribute to age-related fiber atrophy.
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Affiliation(s)
- C M Lee
- Department of Animal Health and Biomedical Sciences, University of Wisconsin, Madison 53706, USA
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24
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Müller-Höcker J, Jacob U, Seibel P. Hashimoto thyroiditis is associated with defects of cytochrome-c oxidase in oxyphil Askanazy cells and with the common deletion (4,977) of mitochondrial DNA. Ultrastruct Pathol 1998; 22:91-100. [PMID: 9491221 DOI: 10.3109/01913129809032263] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The activity of cytochrome-c oxidase, the terminal enzyme of the respiratory chain (complex IV), was studied at the ultrastructural level in a case of Hashimoto thyroiditis. Cytochrome-c oxidase showed a heterogeneous reaction pattern in oxyphil cells, with scattered foci of oxyphil cells lacking cytochrome-c oxidase staining. In most of the cells the defect involved all the mitochondria, but there were also oxyphil cells with a heterogeneous mitochondrial population characterized by an intracellular coexistence of mitochondria with either intact cytochrome-c oxidase or lacking activity. Immunocytochemistry further disclosed loss of mitochondrially and nuclearly encoded subunits of the enzyme. Molecular genetic analysis of mitochondrial DNA (mtDNA) revealed the presence of the 4977 base pair deletion ("common deletion") of mtDNA (8,482-13,459) in the affected areas but not in normal thyroid tissue of the patient. The amount of deleted mtDNA varied between 2 and 8% of total mtDNA. The results demonstrate that oxyphil cell change in Hashimoto thyroiditis is associated with functional and molecular genetic defects of the respiratory chain.
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Affiliation(s)
- J Müller-Höcker
- Pathologisches Institut, Ludwig-Maximilians Universität, München, Germany
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25
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Porter JD, Karathanasis P, Bonner PH, Brueckner JK. The oculomotor periphery: the clinician's focus is no longer a basic science stepchild. Curr Opin Neurobiol 1997; 7:880-7. [PMID: 9464973 DOI: 10.1016/s0959-4388(97)80150-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The study of the oculomotor periphery, the extraocular muscles and their orbital attachments, is undergoing a rapid expansion. This is an important progression for both basic and clinical communities as, for too long, the ophthalmologist has worked primarily in the periphery and the basic researcher has been occupied with study of the central components of the oculomotor system. From recent studies, it is clear that the morphology, cell and molecular biology, and genetics of the eye muscles and their corresponding motoneuron pools, and muscle attachments within the orbit are more complex than has heretofore been appreciated.
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Affiliation(s)
- J D Porter
- Department of Anatomy and Neurobiology, University of Kentucky, Lexington 40536-0084, USA.
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