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Foutouhi A, Bulkely E, de la Fuente A, Gonzalez K, Meyers S. Effects of substrate availability and mitochondrial disruption on oxidative metabolism and sperm motility in fertile dogs. Reprod Domest Anim 2024; 59:e14664. [PMID: 39010850 DOI: 10.1111/rda.14664] [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: 01/03/2024] [Revised: 06/01/2024] [Accepted: 06/28/2024] [Indexed: 07/17/2024]
Abstract
In several mammalian species, the measurement of mitochondrial oxygen consumption (MITOX) under different metabolic conditions has demonstrated a positive correlation with sperm motility and may be a sensitive indicator of mitochondrial health. In general, the maintenance of sperm motility and many key sperm functions and fertilizing events are heavily energy-dependent processes, and some species-specific substrate preferences exist. Although canine sperm have been known to undergo capacitation and maintain motility with supplementation of a wide range of energy substrates, the relationship between mitochondrial function, and the maintenance of oxidative metabolism and sperm motility remain unclear. The objective of this study was to explore the metabolic flexibility of canine sperm, and to investigate the relationship between mitochondrial function, and maintenance of motility under differing nutrient conditions. We explored substrate preferences and the bioenergetics underlying maintenance of canine sperm motility by monitoring mitochondrial oxidative function and sperm kinematics in the presence of mitochondrial effector drug treatments: FCCP, antimycin (ANTI), and oligomycin (OLIGO). We hypothesized that canine sperm possess the ability to use compensatory pathways and utilize diverse nutrient sources in the maintenance of motility. Oxygen consumption (change in pO2, oxygen partial pressure) and sperm kinematics (CASA) were measured concurrently (t0-t30) to assess the relationship between oxidative metabolism and maintenance of sperm motility in dogs. Four media were tested: containing glucose, lactate, and pyruvate (GLP), containing glucose (G), fructose (F), or lactate and pyruvate (LP). In the absence of pharmacological inhibition of the electron transport chain, energetic substrate had no effect on sperm kinematics in fertile dogs. Following mitochondrial disruption by ANTI and OLIGO, mitochondrial oxygen consumption was negatively correlated with several sperm motility parameters in GLP, G, F, and LP media. In every media, FCCP treatment quickly induced significantly higher oxygen consumption than in untreated sperm, and spare respiratory capacity, the maximal inducible oxidative metabolism, was high. With respiratory control ratios RCR >1 there was no indication of bioenergetic dysfunction in any media type, indicating that sperm mitochondria of fertile dogs have a high capacity for substrate oxidation and ATP turnover regardless of substrate. Our results suggest MITOX assessment is a valuable tool for assessing mitochondrial functionality, and that canine sperm employ flexible energy management systems which may be exploited to improve sperm handling and storage.
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Affiliation(s)
- Azarene Foutouhi
- Department of Anatomy, Physiology and Cell Biology, School of Veterinary Medicine, University of California, Davis, California, USA
| | - Evelyn Bulkely
- Department of Anatomy, Physiology and Cell Biology, School of Veterinary Medicine, University of California, Davis, California, USA
| | - Alejandro de la Fuente
- Department of Anatomy, Physiology and Cell Biology, School of Veterinary Medicine, University of California, Davis, California, USA
| | - Kris Gonzalez
- Guide Dogs for the Blind, San Rafael, California, USA
| | - Stuart Meyers
- Department of Anatomy, Physiology and Cell Biology, School of Veterinary Medicine, University of California, Davis, California, USA
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2
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Martín-Cano FE, Gaitskell-Phillips G, Becerro-Rey L, da Silva E, Masot J, Redondo E, Silva-Rodríguez A, Ortega-Ferrusola C, Gil MC, Peña FJ. Pyruvate enhances stallion sperm function in high glucose media improving overall metabolic efficiency. Theriogenology 2024; 215:113-124. [PMID: 38029686 DOI: 10.1016/j.theriogenology.2023.11.019] [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: 08/31/2023] [Revised: 11/16/2023] [Accepted: 11/16/2023] [Indexed: 12/01/2023]
Abstract
If a mechanism of more efficient glycolysis depending on pyruvate is present in stallion spermatozoa, detrimental effects of higher glucose concentrations that are common in current commercial extenders could be counteracted. To test this hypothesis, spermatozoa were incubated in a 67 mM Glucose modified Tyrode's media in the presence of 1- or 10-mM pyruvate and in the Tyrode's basal media which contains 5 mM glucose. Spermatozoa incubated for 3 h at 37 °C in 67 mM Tyrode's media with 10 mM pyruvate showed increased motility in comparison with aliquots incubated in Tyrode's 5 mM glucose and Tyrode's 67 mM glucose (57.1 ± 3.5 and 58.1 ± 1.9 to 73.0 ± 1.1 %; P < 0.01). Spermatozoa incubated in Tyrode's with 67 mM glucose 10 mM pyruvate maintained the viability along the incubation (64.03 ± 15.4 vs 61.3 ± 10.2), while spermatozoa incubated in 67 mM Glucose-Tyrode's showed a decrease in viability (38.01 ± 11.2, P < 0.01). 40 mM oxamate, an inhibitor of the lactate dehydrogenase LDH, reduced sperm viability (P < 0.05, from 76 ± 5 in 67 mM Glucose/10 mM pyruvate to 68.0 ± 4.3 %, P < 0.05). Apoptotic markers increased in the presence of oxamate. (P < 0.01). UHPLC/MS/MS showed that 10 mM pyruvate increased pyruvate, lactate, ATP and NAD+ while phosphoenolpyruvate decreased. The mechanisms that explain the improvement of in presence of 10 mM pyruvate involve the conversion of lactate to pyruvate and increased NAD+ enhancing the efficiency of the glycolysis.
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Affiliation(s)
- Francisco E Martín-Cano
- Laboratory of Equine Reproduction and Equine Spermatology, Veterinary Teaching Hospital, University of Extremadura, Cáceres, Spain
| | - Gemma Gaitskell-Phillips
- Laboratory of Equine Reproduction and Equine Spermatology, Veterinary Teaching Hospital, University of Extremadura, Cáceres, Spain
| | - Laura Becerro-Rey
- Laboratory of Equine Reproduction and Equine Spermatology, Veterinary Teaching Hospital, University of Extremadura, Cáceres, Spain
| | - Eva da Silva
- Laboratory of Equine Reproduction and Equine Spermatology, Veterinary Teaching Hospital, University of Extremadura, Cáceres, Spain
| | - Javier Masot
- Laboratory of Equine Reproduction and Equine Spermatology, Veterinary Teaching Hospital, University of Extremadura, Cáceres, Spain
| | - Eloy Redondo
- Laboratory of Equine Reproduction and Equine Spermatology, Veterinary Teaching Hospital, University of Extremadura, Cáceres, Spain
| | - Antonio Silva-Rodríguez
- Facility of Innovation and Analysis in Animal Source Foodstuffs, University of Extremadura, Cáceres, Spain
| | - Cristina Ortega-Ferrusola
- Laboratory of Equine Reproduction and Equine Spermatology, Veterinary Teaching Hospital, University of Extremadura, Cáceres, Spain
| | - María Cruz Gil
- Laboratory of Equine Reproduction and Equine Spermatology, Veterinary Teaching Hospital, University of Extremadura, Cáceres, Spain
| | - Fernando J Peña
- Laboratory of Equine Reproduction and Equine Spermatology, Veterinary Teaching Hospital, University of Extremadura, Cáceres, Spain.
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Bucci D, Spinaci M, Bustamante-Filho IC, Nesci S. The sperm mitochondria: clues and challenges. Anim Reprod 2023; 19:e20220131. [PMID: 36819482 PMCID: PMC9924773 DOI: 10.1590/1984-3143-ar2022-0131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Accepted: 01/24/2023] [Indexed: 02/19/2023] Open
Abstract
Sperm cells rely on different substrates to fulfil thei energy demand for different functions and diverse moments of their life. Species specific mechanism involve both energy substrate transport and their utilization: hexose transporters, a protein family of facilitative passive transporters of glucose and other hexose, have been identified in spermatozoa of different species and, within the species, their localization has been identified and, in some cases, linked to specific glycilitic enzyme presence. The catabolism of hexose sources for energy purposes has been studied in various species, and recent advances has been made in the knowledge of metabolic strategies of sperm cells. In particular, the importance of aerobic metabolism has been defined and described in horse, boar and even mouse spermatozoa; bull sperm cells demonstrate to have a good adaptability and capacity to switch between glycolysis and oxidative phosphorylation; finally, dog sperm cells have been demonstrated to have a great plasticity in energy metabolism management, being also able to activate the anabolic pathway of glycogen syntesis. In conclusion, the study of energy management and mitochondrial function in spermatozoa of different specie furnishes important base knowledge to define new media for preservation as well as newbases for reproductive biotechnologies.
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Affiliation(s)
- Diego Bucci
- Department of Veterinay Medical Sciences, University of Bologna, Bologna, Italy,Corresponding author:
| | - Marcella Spinaci
- Department of Veterinay Medical Sciences, University of Bologna, Bologna, Italy
| | | | - Salvatore Nesci
- Department of Veterinay Medical Sciences, University of Bologna, Bologna, Italy
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Comparative oxidative metabolism in mammalian sperm. Anim Reprod Sci 2022; 247:107095. [DOI: 10.1016/j.anireprosci.2022.107095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Revised: 10/10/2022] [Accepted: 10/14/2022] [Indexed: 11/18/2022]
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5
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Bulkeley EA, Foutouhi A, Wigney K, Santistevan AC, Collins C, McNabb B, Meyers S. Effects from disruption of mitochondrial electron transport chain function on bull sperm motility. Theriogenology 2021; 176:63-72. [PMID: 34571399 DOI: 10.1016/j.theriogenology.2021.09.015] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 09/09/2021] [Accepted: 09/16/2021] [Indexed: 11/17/2022]
Abstract
Sperm mitochondrial function is essential for normal physiology and fertility, but the importance of mitochondrial activity to support specific sperm functions, such as motility, varies between species. It was previously believed that mitochondrial function was not necessary for bull sperm motility [1]; however, this theory is contradicted by recently reported findings that the upper fraction of bull sperm swim-up preparations had both high motility and elevated mitochondrial oxygen consumption rates [2]. The objective of this study was to investigate the relationship between mitochondrial function and motility in bull sperm. We hypothesized that sperm motility would be positively correlated with mitochondrial oxygen consumption (MITOX) but unaffected by pharmacological inhibition of electron transport chain (ETC) activity. This was accomplished by monitoring both mitochondrial oxygen consumption and motility parameters in the presence of mitochondrial effector drug treatments. Duplicate ejaculates were collected by electroejaculation from Black Angus bulls (n = 4). Oxygen consumption, as % air saturation (pO2; oxygen partial pressure), over time was monitored in the presence of 5 drug treatments: vehicle control, FCCP, Antimycin (ANTI), Oligomycin (Oligo), and FCCP + Oligomycin (FCCP + OLIGO). Duplicate aliquots were prepared for concurrent motility assessment by computer-assisted sperm analysis (CASA) at 6 and 30 min post-treatment (t6 and t30). The impact of treatments on pO2 (in % air saturation) over time were assessed by generalized linear mixed effects modeling (GLMM) which was also used to test for differences in average motility across treatment conditions and time points (t6 and t30). Pearson product-moment correlation was used to investigate relationships between oxygen consumption and motility parameters. Overall, pO2 differed over time between treatment conditions (p < 0.0001). When compared to the vehicle treatment, ANTI and OLIGO significantly inhibited oxygen consumption (p < 0.05, adjusted), and FCCP stimulated a marked increase in oxygen consumption. No significant differences in motility over time were observed between treatments, so comparison of motility parameters between treatment conditions was performed with pooled timepoints. Motility parameters were only observed to differ significantly from the vehicle with ANTI Treatment, for which significant decreases in numerous parameters, including total motility (p = 0.007), progressive motility (p = 0.01), DAP (p = 0.01), VAP (p = 0.01) and VSL (p = 0.02) were identified. For the vehicle treatment, correlational analysis did not reveal any significant correlations between pO2 and any motility parameters at t6; however, several significant correlations were identified at t30. Mean pO2 was negatively correlated with local motility (p < 0.01) and positively correlated with DCL, DAP, and VCL (p < 0.05). Results from this study suggest that bovine sperm motility is impacted by mitochondrial functionality, with ETC inhibition by ANTI causing significant reduction in motility parameters. This study also demonstrates the use of a new technology for the assessment of bovine sperm mitochondrial function. This modality for evaluation of bull sperm mitochondrial function will inform future efforts to understand bull sperm function and fertility and aid investigations into toxicological agents.
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Affiliation(s)
- Evelyn A Bulkeley
- Department of Anatomy, Physiology, and Cell Biology, University of California, Davis, United States
| | - Azarene Foutouhi
- Department of Anatomy, Physiology, and Cell Biology, University of California, Davis, United States
| | - Kayla Wigney
- Department of Anatomy, Physiology, and Cell Biology, University of California, Davis, United States
| | | | - Christine Collins
- Department of Anatomy, Physiology, and Cell Biology, University of California, Davis, United States
| | - Bret McNabb
- Department of Population Health and Reproduction, School of Veterinary Medicine, University of California, Davis, United States
| | - Stuart Meyers
- Department of Anatomy, Physiology, and Cell Biology, University of California, Davis, United States.
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Effects of glucose metabolism pathways on sperm motility and oxidative status during long-term liquid storage of goat semen. Theriogenology 2016; 86:839-49. [DOI: 10.1016/j.theriogenology.2016.03.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Revised: 03/03/2016] [Accepted: 03/03/2016] [Indexed: 11/23/2022]
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7
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Paventi G, Lessard C, Bailey JL, Passarella S. In boar sperm capacitation L-lactate and succinate, but not pyruvate and citrate, contribute to the mitochondrial membrane potential increase as monitored via safranine O fluorescence. Biochem Biophys Res Commun 2015; 462:257-62. [PMID: 25956060 DOI: 10.1016/j.bbrc.2015.04.128] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Accepted: 04/26/2015] [Indexed: 11/28/2022]
Abstract
Having ascertained using JC-1 as a probe that, in distinction with the controls, during capacitation boar sperm maintains high mitochondrial membrane potential (ΔΨ), to gain some insight into the role of mitochondria in capacitation, we monitored ΔΨ generation due to externally added metabolites either in hypotonically-treated spermatozoa (HTS) or in intact cells by using safranine O as a probe. During capacitation, the addition to HTS of L-lactate and succinate but not those of pyruvate, citrate and ascorbate + TMPD resulted in increase of ΔΨ generation. Accordingly, the addition of L-lactate and succinate, but not that of citrate, to intact sperm resulted in ΔΨ generation increased in capacitation.
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Affiliation(s)
- Gianluca Paventi
- Dipartimento di Medicina e Scienze della Salute "V. Tiberio", Università del Molise, via de Sanctis, Campobasso, Italy
| | - Christian Lessard
- Centre de Recherche en Biologie de la Reproduction, Département des Sciences Animales, Université Laval, Québec, Canada
| | - Janice L Bailey
- Centre de Recherche en Biologie de la Reproduction, Département des Sciences Animales, Université Laval, Québec, Canada.
| | - Salvatore Passarella
- Dipartimento di Medicina e Scienze della Salute "V. Tiberio", Università del Molise, via de Sanctis, Campobasso, Italy.
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Bioenergetics of mammalian sperm capacitation. BIOMED RESEARCH INTERNATIONAL 2014; 2014:902953. [PMID: 24791005 PMCID: PMC3984864 DOI: 10.1155/2014/902953] [Citation(s) in RCA: 106] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/01/2014] [Revised: 03/02/2014] [Accepted: 03/03/2014] [Indexed: 11/17/2022]
Abstract
After ejaculation, the mammalian male gamete must undergo the capacitation process, which is a prerequisite for egg fertilization. The bioenergetics of sperm capacitation is poorly understood despite its fundamental role in sustaining the biochemical and molecular events occurring during gamete activation. Glycolysis and mitochondrial oxidative phosphorylation (OXPHOS) are the two major metabolic pathways producing ATP which is the primary source of energy for spermatozoa. Since recent data suggest that spermatozoa have the ability to use different metabolic substrates, the main aim of this work is to present a broad overview of the current knowledge on the energy-producing metabolic pathways operating inside sperm mitochondria during capacitation in different mammalian species. Metabolism of glucose and of other energetic substrates, such as pyruvate, lactate, and citrate, is critically analyzed. Such knowledge, besides its obvious importance for basic science, could eventually translate into the development of novel strategies for treatment of male infertility, artificial reproduction, and sperm selection methods.
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Aitken RJ, Whiting S, De Iuliis GN, McClymont S, Mitchell LA, Baker MA. Electrophilic aldehydes generated by sperm metabolism activate mitochondrial reactive oxygen species generation and apoptosis by targeting succinate dehydrogenase. J Biol Chem 2012; 287:33048-60. [PMID: 22851170 DOI: 10.1074/jbc.m112.366690] [Citation(s) in RCA: 168] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Oxidative stress is a major cause of defective sperm function in cases of male infertility. Such stress is known to be associated with high levels of superoxide production by the sperm mitochondria; however, the causes of this aberrant activity are unknown. Here we show that electrophilic aldehydes such as 4-hydroxynonenal (4HNE) and acrolein, generated as a result of lipid peroxidation, target the mitochondria of human spermatozoa and stimulate mitochondrial superoxide generation in a dose- and time-dependent manner. The activation of mitochondrial electron leakage by 4HNE is shown to involve the disruption of succinate dehydrogenase activity and subsequent activation of an intrinsic apoptotic cascade beginning with a loss of mitochondrial membrane potential and terminating in oxidative DNA adduct formation, DNA strand breakage, and cell death. A tight correlation between spontaneous mitochondrial superoxide generation and 4HNE content (R(2) = 0.89) in untreated populations of human spermatozoa emphasized the pathophysiological significance of these findings. The latter also provide a biochemical explanation for the self-perpetuating nature of oxidative stress in the male germ line, with the products of lipid peroxidation stimulating free radical generation by the sperm mitochondria in a positive feedback loop.
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Affiliation(s)
- R John Aitken
- Priority Research Centre in Reproductive Science, Discipline of Biological Sciences, Faculty of Science and IT, University of Newcastle, University Drive, Callaghan, New South Wales 2308, Australia.
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Piomboni P, Focarelli R, Stendardi A, Ferramosca A, Zara V. The role of mitochondria in energy production for human sperm motility. ACTA ACUST UNITED AC 2011; 35:109-24. [DOI: 10.1111/j.1365-2605.2011.01218.x] [Citation(s) in RCA: 245] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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11
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Hereng TH, Elgstøen KBP, Cederkvist FH, Eide L, Jahnsen T, Skålhegg BS, Rosendal KR. Exogenous pyruvate accelerates glycolysis and promotes capacitation in human spermatozoa. Hum Reprod 2011; 26:3249-63. [PMID: 21946930 PMCID: PMC3212877 DOI: 10.1093/humrep/der317] [Citation(s) in RCA: 96] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND There has been an ongoing debate in the reproductive field about whether mammalian spermatozoa rely on glycolysis, oxidative phosphorylation or both for their energy production. Recent studies have proposed that human spermatozoa depend mainly on glucose for motility and fertilization but the mechanism behind an efficient glycolysis in human spermatozoa is not well understood. Here, we demonstrate how human spermatozoa utilize exogenous pyruvate to enhance glycolytic ATP production, motility, hyperactivation and capacitation, events that are crucial for male fertility. METHODS Purified human spermatozoa from healthy donors were incubated under capacitating conditions (including albumin, bicarbonate and glucose) and tested for changes in ATP levels, motility, hyperactivation and tyrosine phosphorylation after treatment with pyruvate. The experiments were repeated in the presence of sodium cyanide in order to assess the contribution from mitochondrial respiration. The metabolism of 13C labeled glucose and pyruvate was traced by a combination of liquid chromatography and mass spectrometry. RESULTS The treatment of human spermatozoa with exogenous pyruvate increased intracellular ATP levels, progressive motility and hyperactivation by 56, 21 and 130%, respectively. In addition, added pyruvate induced a significant increase in tyrosine phosphorylation levels. Blocking of the electron transport chain did not markedly affect the results, indicating that the mechanism is independent of oxidative phosphorylation. However, the observed effects could be counteracted by oxamate, an inhibitor of lactate dehydrogenase (LDH). Metabolic tracing experiments revealed that the observed rise in ATP concentration resulted from an enhanced glycolytic flux, which was increased by more than 50% in the presence of exogenous pyruvate. Moreover, all consumed 13C labeled pyruvate added was converted to lactate rather than oxidized in the tricarboxylic acid cycle. CONCLUSIONS Human spermatozoa seem to rely mainly, if not entirely, on glycolysis as the source of ATP fueling the energy-demanding processes of motility and capacitation. The efficient glycolysis is dependent on exogenous pyruvate, which indirectly feeds the accelerated glycolysis with NAD+ through the LDH-mediated conversion of pyruvate to lactate. Pyruvate is present in the human female reproductive tract at concentrations in accordance with our results. As seen in other mammals, the motility and fertility of human spermatozoa seem to be dictated by the available energy substrates present in the conspecific female.
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Affiliation(s)
- T H Hereng
- Spermatech AS, Forskningsveien 2A, 0373 Oslo, Norway
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12
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Chinopoulos C. The "B space" of mitochondrial phosphorylation. J Neurosci Res 2011; 89:1897-904. [PMID: 21541983 DOI: 10.1002/jnr.22659] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2010] [Revised: 02/09/2011] [Accepted: 03/10/2011] [Indexed: 11/07/2022]
Abstract
It was recently shown that, in progressively depolarizing mitochondria, the F(0) -F(1) ATP synthase and the adenine nucleotide translocase (ANT) may change directionality independently from each other (Chinopoulos et al. [2010] FASEB J. 24:2405). When the membrane potentials at which these two molecular entities reverse directionality, termed reversal potential (Erev), are plotted as a function of matrix ATP/ADP ratio, an area of the plot is bracketed by the Erev_ATPase and the Erev_ANT, which we call "B space". Both reversal potentials are dynamic, in that they depend on the fluctuating values of the participating reactants; however, Erev_ATPase is almost always more negative than Erev_ANT. Here we review the conditions that define the boundaries of the "B space". Emphasis is placed on the role of matrix substrate-level phosphorylation, because during metabolic compromise this mechanism could maintain mitochondrial membrane potential and prevent the influx of cytosolic ATP destined for hydrolysis by the reversed F(0) -F(1) ATP synthase.
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13
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Córdoba M, Pintos L, Beconi MT. Differential activities of malate and isocitrate NAD(P)-dependent dehydrogenases are involved in the induction of capacitation and acrosome reaction in cryopreserved bovine spermatozoa. Andrologia 2005; 37:40-6. [PMID: 15644062 DOI: 10.1111/j.1439-0272.2004.00650.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Sperm catabolic processes produce energy for capacitation and acrosome reaction induction required for oocyte fertilization. The aim was to determine metabolic enzymes' activities and their participation in the supply of energy and generation of the redox state to acquire fertilizing capacity. Capacitation was induced with heparin and quercetin, and the acrosome reaction with progesterone. Enzymatic activities were determined spectrophotometrically. The chlortetracycline and differential-interferential contrast microscopy/tryptan blue techniques were used to evaluate capacitation and acrosome reaction, acrosomal integrity and sperm viability respectively. A 2 : 1 and 3 : 1 ratio were obtained for isocitrate dehydrogenase (IDH)-NADP/NAD and malate dehydrogenase (MDH)-NADP/NAD activities respectively. MDH-NADP activity remained constant with different treatments, unlike MDH-NAD activity, which diminished with both capacitation inducers and in acrosome-reacted spermatozoa previously treated with heparin (P < 0.05). IDH-NADP decreased its activity 50% in spermatozoa capacitated with heparin and acrosome reacted with progesterone (P < 0.05). Capacitation and acrosome reaction processes induced with heparin and progesterone, respectively, involve a differential oxidative metabolism, with the participation of MDH-NAD(P) and IDH-NAD(P) enzymes, whose activities would be linked to the malate-aspartate, lactate-pyruvate and isocitrate cytosolic-mitochondrial shuttles. These enzymes play a major role in supplying reduction equivalents and/or energy required for capacitation and acrosome reaction in cryopreserved bovine spermatozoa.
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Affiliation(s)
- M Córdoba
- Area of Biochemistry, School of Veterinary Sciences, University of Buenos Aires, Buenos Aires, Argentina
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14
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Piasecka M, Wenda-Rózewicka L, Ogoński T. Computerized analysis of cytochemical reactions for dehydrogenases and oxygraphic studies as methods to evaluate the function of the mitochondrial sheath in rat spermatozoa. Andrologia 2001; 33:1-12. [PMID: 11167513 DOI: 10.1046/j.1439-0272.2001.00369.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Cytochemical reactions for mitochondrial NADH-dependent dehydrogenases (diaphorase/NADH which is related to flavoprotein), NAD-dependent dehydrogenases (isocitrate, malate) and succinate dehydrogenase were carried out in rat spermatozoa. In addition to a morphological evaluation, the intensity of the reactions was assessed using a computer image analysing system (Quantimet 600 S). The intensity of the reactions was examined in sperm midpieces by measuring integrated optical density (IOD) and mean optical density (MOD). The activity of mitochondrial respiratory chain complexes was also analysed using the polarographic method. In the population of spermatozoa studied, all whole spermatozoa midpieces were completely filled with formazans, the product of the cytochemical reaction. These morphological findings corresponded to the values obtained for IOD and MOD for the given enzymes. In the oxygraphic studies, the spermatozoa demonstrated consumption of oxygen in the presence of substrates for I, II and IV complexes and their mitochondria revealed normal integrity and sensitivity to the substrates and inhibitors. However, the oxygraphic studies revealed differences between the sperm and somatic cells. These differences concerned the stimulation of pyruvate oxidation by malate, the lack of an effect of malonic acid on phenazine methosulphate (an acceptor of electrons) oxidation and the lack of an effect of cytochrome c on ascorbate oxidation. The cytochemical method, together with densitometric measurements, enables: (1) the reaction intensity to be determined objectively; (2) subtle and dramatic differences in reaction intensity to be revealed between spermatozoa that do not differ under morphological evaluation of the intensity; (3) possible defects within the mitochondrial sheath to be located and assessed in a large number of spermatozoa. This method can be used as a screening method alongside the routine morphological examination of spermatozoa. On the other hand, the oxygraphic method in the inner membrane of mitochondria can reveal functional changes which are related to the action of respiratory chain complexes and display characteristic features of mitochondria energy metabolism. The methods used are complementary and allow the complex evaluation of mitochondria in spermatozoa. Both methods can be used in experimental and clinical studies.
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Affiliation(s)
- M Piasecka
- Department of Histology and Embryology, Pomeranian Academy of Medicine, Szczecin, Poland
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15
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Benvenga S, Lakshmanan M, Trimarchi F. Carnitine is a naturally occurring inhibitor of thyroid hormone nuclear uptake. Thyroid 2000; 10:1043-50. [PMID: 11201848 DOI: 10.1089/thy.2000.10.1043] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Carnitine (3-hydroxy-4N-trimethylammoniumbutanoate) is a naturally occurring quaternary amine that is ubiquitous in mammalian tissues (concentrations in the order of mM). Based on limited studies of approximately 40 years ago, carnitine was considered to be a peripheral antagonist of thyroid hormone (TH) action. These interesting observations have not been explored. To study the biologic basis of this effect, we tested the following possibilities in three TH-responsive cell lines: (1) inhibition of TH entry into cells; (2) inhibition of TH entry into the nucleus; (3) inhibition of TH interaction with the isolated nuclei; and (4) facilitated efflux of TH from cells. On a preliminary basis we had verified that these cell lines (human skin fibroblasts, human hepatoma cells HepG2, and mouse neuroblastoma cells NB 41A3) take up 14Ccarnitine; however, there was no 14Ccarnitine uptake into the nuclei. Concentrations of unlabeled carnitine as high as 100 mM did not affect (125I)T3 binding to isolated nuclei or exit of TH from cells, thus excluding possibilities numbered 3 and 4. At 10 mM camitine, (125I)T3 and (125I)T4 whole-cell uptake was inhibited by approximately 20% in fibroblasts and in HepG2, but by approximately 5% in NB 41A3 cells. Inhibition of T3 nuclear uptake was evaluated in HepG2 and NB 41A3 cells. At 10 mM carnitine, inhibition of T3 nuclear uptake was disproportionately higher, namely approximately 25% in neurons and 35% in hepatocytes. At 50 mM carnitine, there was a minimal additional decrease in whole-cell uptake of either hormone but a marked decrease in T3 nuclear uptake. The latter inhibition was approximately 60% in neurons and 70% in hepatocytes. We are aware of no inhibitor of TH uptake that has such a markedly different effect on the nuclear versus whole-cell uptake. Our data are consistent with carnitine being a peripheral antagonist of TH action, and they indicate a site of inhibition at or before the nuclear envelope.
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Affiliation(s)
- S Benvenga
- Cattedra di Endocrinologia, University of Messina, School of Medicine, Italy.
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Rosenthal RE, Williams R, Bogaert YE, Getson PR, Fiskum G. Prevention of postischemic canine neurological injury through potentiation of brain energy metabolism by acetyl-L-carnitine. Stroke 1992; 23:1312-7; discussion 1317-8. [PMID: 1519288 DOI: 10.1161/01.str.23.9.1312] [Citation(s) in RCA: 119] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
BACKGROUND AND PURPOSE Mechanisms of ischemia/reperfusion brain injury include altered patterns of energy metabolism that may be amenable to pharmacological manipulation. The purpose of this study was to test the effectiveness of postischemic acetyl-L-carnitine administration on potentiation of metabolic recovery and prevention of neurological morbidity in a clinically relevant model of complete, global cerebral ischemia and reperfusion. METHODS Neurological deficit scoring as well as spectrophotometric and fluorescent assays of frontal cortex lactate and pyruvate levels were used in a canine model employing 10 minutes of cardiac arrest followed by restoration of spontaneous circulation for 2 or 24 hours. RESULTS Dogs treated with acetyl-L-carnitine exhibited significantly lower neurological deficit scores (p = 0.0037) and more normal cerebral cortex lactate/pyruvate ratios than did vehicle-treated control animals. CONCLUSIONS Postischemic administration of acetyl-L-carnitine potentiates normalization of brain energy metabolites and substantially improves neurological outcome in a clinically relevant model of global cerebral ischemia and reperfusion.
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Affiliation(s)
- R E Rosenthal
- Department of Emergency Medicine, George Washington University Medical Center, DC 20037
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Breitbart H, Wehbie R, Lardy HA. Calcium transport in bovine sperm mitochondria: effect of substrates and phosphate. BIOCHIMICA ET BIOPHYSICA ACTA 1990; 1026:57-63. [PMID: 1696124 DOI: 10.1016/0005-2736(90)90332-i] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Calcium uptake into filipin-treated bovine spermatozoa is completely inhibited by the uncoupler CCCP or by ruthenium red. Both Pi and mitochondrial substrates are required to obtain the maximal rate of calcium uptake into the sperm mitochondria. Bicarbonate and other anions such as lactate, acetate or beta-hydroxybutyrate do not support a high rate of calcium uptake. There are significant differences among various mitochondrial substrates in supporting calcium uptake. The best substrates are durohydroquinone, alpha-glycerophosphate and lactate. Pyruvate is a relatively poor substrate, and its rate can be greatly enhanced by malate or succinate but not by oxalacetate or lactate. This stimulation is blocked by the dicarboxylate translocase inhibitor, butylmalonate and can be mimiced by the non-metabolized substrate D-malate. The Ka for pyruvate was found to be 17 microM and 67 microM in the presence and absence of L-malate, respectively. The Ka for L-malate is 0.12 mM. It is suggested that in addition to the known pyruvate/lactate translocase there is a second translocase for pyruvate which is malate/succinate-dependent and does not transport lactate. In the presence of succinate, glutamate stimulates calcium uptake 3-fold, and this effect is not inhibited by rotenone. In the presence of glutamate plus malate or oxalacetate there is only an additive effect. It is suggested that glutamate stimulates succinate transport and/or oxidation in bovine sperm mitochondria. The alpha-hydroxybutyrate is almost as good as lactate in supporting calcium uptake. Since the alpha-keto product is not further metabolized in the citric acid cycle, it is suggested that lactate can supply the mitochondrial needs for NADH from its oxidation to pyruvate by the sperm lactate dehydrogenase x. Thus, when there is sufficient lactate in the sperm mitochondria, pyruvate need not be further metabolized in the citric acid cycle in order to supply more NADH.
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Affiliation(s)
- H Breitbart
- Department of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
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A factor in human seminal plasma which affects carnitine accumulation in bovine epididymal sperm**This is publication 1056 from the Department of Cell and Molecular Biology, Medical College of Georgia.††Supported in part by the National Institutes of Health grant AM 30833 and by the Muscular Dystrophy Association. Fertil Steril 1988. [DOI: 10.1016/s0015-0282(16)59903-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Henninger C, Clouet P, Cao Danh H, Pascal M, Bezard J. Effects of fenofibrate treatment on fatty acid oxidation in liver mitochondria of obese Zucker rats. Biochem Pharmacol 1987; 36:3231-6. [PMID: 3663237 DOI: 10.1016/0006-2952(87)90638-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Obese Zucker rats were dosed orally for one week with fenofibrate (100 mg/kg). Liver weights of treated rats as expressed as percent of body weight were slightly increased, while protein, DNA and lipid contents were unaffected per g of liver or increased when expressed in whole liver. Compared with the control animals, activities of fatty acid oxidase, of the peroxisomal fatty acid-oxidizing system and of catalase were markedly increased by fenofibrate both per g of liver and per total liver, while urate oxidase activity was unchanged when expressed per g of liver. The activity of monoamine oxidase and that of cytochrome c oxidase used as marker enzymes for mitochondria were increased only when expressed per total liver. However, fenofibrate treatment induced a pronounced increase in the activities of mitochondrial palmitoyl-CoA dehydrogenase and carnitine acyltransferases, particularly carnitine acetyltransferase. Fenofibrate also caused a significant increase of carnitine content in liver and hepatic mitochondria. The greatest observed increases were in free carnitine and in the rate of carnitine-dependent oleate oxidation, which might be favoured in vivo by a lesser sensitivity of CPT-I to a malonyl-CoA inhibitory effect. The present results suggest that fenofibrate treatment induces increased hepatic mitochondrial beta-oxidation in obese Zucker rats.
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Affiliation(s)
- C Henninger
- Laboratoire de Physiologie Animale et de la Nutrition, U.A. CNRS 273, Faculté des Sciences Mirande, Dijon, France
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Giridharan N, Bamji MS, Madhyastha MN. In vitro effects of gossypol on testicular lactic dehydrogenase-X and other dehydrogenases. J Biosci 1987. [DOI: 10.1007/bf02704695] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Tomamichel GR, Bandhauer K. Seminal carnitine content in obstructive azoospermia. Correlation with the anatomic level of obstruction. JOURNAL OF ANDROLOGY 1986; 7:328-30. [PMID: 3771371 DOI: 10.1002/j.1939-4640.1986.tb00942.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Free carnitine in human semen originates predominantly in the epididymis. The role of carnitine in the evaluation of different forms of obstructive azoospermia was studied in 42 patients. In 14 of the men, a bilateral vasectomy had been performed. In the remaining 28 patients, the occlusion was located within the epididymis. In postvasectomy cases and where the occlusion was located in the cauda epididymidis, carnitine concentrations were low, with mean values of 115.57 mumol/l and 121.28 mumol/l, respectively. When the occlusion was located in the corpus epididymidis, the mean value increased to 194.72 mumol/l. In patients having obstruction of the caput epididymidis or of the rete testis, the mean value of free carnitine was 416.0 mumol/l. After vasovasostomy, a return of free carnitine concentration to the normal range was observed in 10 of 12 cases. The results indicate that there is a significant correlation in patients with obstructive azoospermia between the concentration of free carnitine and the anatomic site of the obstruction. These findings may lead to important conclusions concerning therapy and prognosis for patients presenting with this condition.
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Rigoni F, Deana R. Ruthenium red inhibits the mitochondrial Ca2+ uptake in intact bovine spermatozoa and increases the cytosolic Ca2+ concentration. FEBS Lett 1986; 198:103-8. [PMID: 2420637 DOI: 10.1016/0014-5793(86)81193-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The uptake and cycling of Ca2+ by ejaculated bovine spermatozoa are almost completely abolished by ruthenium red, antimycin A or FCCP. The inhibitory effect of ruthenium red is also observed after washing of the dye-pretreated cells followed by addition of digitonin or filipin. In contrast, the inhibition is overcome by A23187 treatment. It is concluded that ruthenium red penetrates into intact spermatozoa, inhibits the mitochondrial Ca2+ uptake 'in situ', and causes the observed increase of the cytosolic free Ca2+ concentration.
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Burgos C, Gerez de Burgos NM, Rovai LE, Blanco A. In vitro inhibition by gossypol of oxidoreductases from human tissues. Biochem Pharmacol 1986; 35:801-4. [PMID: 3754138 DOI: 10.1016/0006-2952(86)90248-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The effect of gossypol, a polyphenolic compound with antifertility action on human males, has been investigated on the following oxidoreductases purified from human tissues: lactate dehydrogenase (EC 1.1.1.27) isozymes 1 or B4 from heart, 5 or A4 from liver and X or C4 from spermatozoa; malate dehydrogenase (EC 1.1.1.37) mitochondrial and "soluble" isozymes from heart and NADP-glutamate dehydrogenase (EC 1.4.1.4) from liver. Gossypol proved to be a powerful inhibitor of the six enzymes studied. For all of them, inhibition was of the competitive type with respect to the coenzyme and non-competitive in relation to substrate. The lowest ki values were shown for lactate dehydrogenase isozyme 1 or B4 and for the two isozymes of malate dehydrogenase. Results did not show selectivity of gossypol for the sperm-specific isozyme X or C4 of lactate dehydrogenase.
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Shoaf AR, Jarmer S, Harbison RD. Heavy metal inhibition of carnitine acetyltransferase activity in human placental syncytiotrophoblast: possible site of action of HgCl2, CH3HgCl, and CdCl2. TERATOGENESIS, CARCINOGENESIS, AND MUTAGENESIS 1986; 6:351-60. [PMID: 2878501 DOI: 10.1002/tcm.1770060502] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The effect of the heavy metal toxicants HgCl2, CH3HgCl, and CdCl2 on the acetylating activity of membranous carnitine acetyltransferase (CarAc) in membrane vesicles from the maternal surface of human placental syncytiotrophoblast has been investigated. CarAc was inhibited by inorganic and organic mercury and cadmium. Carnitine acetylation was inhibited by as little as 5 microM mercury, with complete inhibition at 50 microM inorganic and organic mercury. Inhibition by cadmium was incomplete (less than 60%) at 500 microM CdCl2. Kinetic studies using Hanes plots revealed a mixed type of inhibition of CarAc by the metals. Cysteine preincubation decreased the amount of inhibition of CarAc by the metals. These results indicate that the inhibition of CarAc by heavy metals occurs by binding of the sulfhydryl on the enzyme by the metals. This interaction may be a mechanism of the heavy metal-induced fetotoxicity.
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DL-aminocarnitine and acetyl-DL-aminocarnitine. Potent inhibitors of carnitine acyltransferases and hepatic triglyceride catabolism. J Biol Chem 1985. [DOI: 10.1016/s0021-9258(17)38636-2] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Huckle WR, Tamblyn TM. Purification and properties of carnitine acetyltransferases from bovine spermatozoa and heart. Arch Biochem Biophys 1983; 226:94-110. [PMID: 6639064 DOI: 10.1016/0003-9861(83)90274-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
To investigate the physical and kinetic properties of sperm carnitine acetyltransferase, the enzyme was purified from bovine spermatozoa and heart muscle. Carnitine acetyltransferase was purified 580-fold from ejaculated bovine spermatozoa to a specific activity of 85 units/mg protein (95% homogeneity). Sperm carnitine acetyltransferase was characterized as a single polypeptide of Mr 62,000 and pI 8.2. Heart carnitine acetyltransferase was purified 650-fold by the same procedure to a final specific activity of 71 units/mg protein. The kinetic properties of purified bovine sperm carnitine acetyltransferase were consistent with the proposed function of this enzyme in acetylcarnitine pool formation. Product inhibition by either acetyl-L-carnitine or CoASH was not sufficient to predict significant in vivo inhibition of acetyl transfer. At high concentrations of L-carnitine, bovine sperm and heart carnitine acetyltransferases were most active with propionyl- and butyryl-CoA substrates, although octanoyl-, iso-butyryl-, and iso-valeryl-CoA were acceptable substrates. Binding of one substrate was enhanced by the presence of the second substrate. Carnitine analogs that have significance in reproduction, such as phosphorylcholine and taurine, did not inhibit carnitine acetyltransferase. Bovine sperm and heart carnitine acetyltransferases were indistinguishable on the basis of purification behavior, pI, pH optima, kinetic properties, acyl-CoA specificity, and sensitivity to sulfhydryl reagents and divalent cations; thus there was no indication that bovine sperm carnitine acetyltransferase is a sperm-specific isozyme.
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Coronel CE, Burgos C, Gerez de Burgos NM, Rovai LE, Blanco A. Catalytic properties of the sperm-specific lactate dehydrogenase (LDH X or C4) from different species. THE JOURNAL OF EXPERIMENTAL ZOOLOGY 1983; 225:379-85. [PMID: 6842156 DOI: 10.1002/jez.1402250305] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
A comparative study of catalytic properties of the sperm-specific lactate dehydrogenase (EC 1.1.1.27) isozyme X or C4 from a variety of animals (boar, bull, goat, Guinea pig, man, mouse, pigeon, rabbit, and rat) is presented. Optimum concentration and Km values for pyruvate, inhibition by substrate, and activity against analog substrates (alpha-ketoacids with linear and branched chains from 4 to 6 carbon atoms) for isozyme X of different species showed significant differences. The observed properties are correlated with available evidence on the metabolic role of the enzyme.
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Carey JE, Olds-Clarke P, Storey BT. Oxidative metabolism of spermatozoa from inbred and random bred mice. THE JOURNAL OF EXPERIMENTAL ZOOLOGY 1981; 216:285-92. [PMID: 7241067 DOI: 10.1002/jez.1402160209] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Epididymal spermatozoa from the random-bred CFW and from the inbred C57 BL/6 strains of mice were treated either hypotonically or with the antibiotic filipin in order to study the mitochondrial oxidative activities of the two strains in the absence of permeability barriers imposed by the plasma membrane. The percentage of motile spermatozoa from C57BL/6 mice was consistently higher than that of CFW mice, but sperm from the latter fertilized a higher percentage of eggs in vitro. In vivo, there was no apparent difference in fertilizing capacity in vivo: no significant difference between strains was observed. There is a strategy of oxidative metabolism in mouse spermatozoa which is common to the two genetic strains of the species tested, but which differs from that of rabbit and bull spermatozoa. The mitochondria of mouse spermatozoa oxidize L--3-glycerolphosphate but not glutamate in the presence of malate; both activities are present in bull spermatozoa but neither are present in rabbit spermatozoa. In common wit those of the mammalian species thus far studied, the mitochondria of mouse spermatozoa readily oxidize lactate and pyruvate in the presence of malate. They also oxidize acetyl CoA, acetyl carnitine, and long-chain acyl CoA esters directly, without the intermediacy of the carnitine esters. Mouse spermatozoa, therefore, have access to endogenous acyl CoA esters as a source of metabolic energy, which is consistent with their ability to maintain motility for 4-6 hours in the absence of added energy sources. Mouse spermatozoa are self-sufficient with regard to oxidative metabolism, which suggests that energy sources are not readily available to them in the mouse female reproductive tract.
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White IG. Epididymal compounds and their influence on the metabolism and survival of spermatozoa. Am J Primatol 1981; 1:143-155. [DOI: 10.1002/ajp.1350010205] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/1980] [Accepted: 12/12/1980] [Indexed: 11/08/2022]
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Storey BT. Strategy of oxidative metabolism in bull spermatozoa. THE JOURNAL OF EXPERIMENTAL ZOOLOGY 1980; 212:61-7. [PMID: 7411077 DOI: 10.1002/jez.1402120109] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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Bookelman H, Trijbels JM, Sengers RC, Janssen AJ, Veerkamp JH, Stadhouders AM. Pyruvate oxidation in rat and human skeletal muscle mitochondria. BIOCHEMICAL MEDICINE 1978; 20:395-403. [PMID: 752349 DOI: 10.1016/0006-2944(78)90089-3] [Citation(s) in RCA: 69] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Van Dop C, Hutson SM, Lardy HA. Selective inhibition of pyruvate and lactate metabolism in bovine epididymal spermatozoa by dinitrophenol and alpha-cyano-3-hydroxycinnamate. Arch Biochem Biophys 1978; 187:235-42. [PMID: 655721 DOI: 10.1016/0003-9861(78)90029-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Tamblyn TM, First NL. Caffeine-stimulated ATP-reactivated motility in a detergent-treated bovine sperm model. Arch Biochem Biophys 1977; 181:208-15. [PMID: 195531 DOI: 10.1016/0003-9861(77)90499-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Hutson SM, van Dop C, Lardy HA. Metabolism of pyruvate and carnitine esters in bovine epididymal sperm mitochondria. Arch Biochem Biophys 1977; 181:345-52. [PMID: 560175 DOI: 10.1016/0003-9861(77)90513-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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