Effect of mitochondrial calcium uniporter blocking on human spermatozoa

Calcium (Ca2+) regulates a number of essential processes in spermatozoa. Ca2+ is taken up by mitochondria via the mitochondrial calcium uniporter (mCU). Oxygen‐bridged dinuclear ruthenium amine complex (Ru360) has been used to study mCU because it is a potent and specific inhibitor of this channel. In bovine spermatozoa, it has been demonstrated that mitochondrial calcium uptake inhibition adversely affects the capacitation process. It has been demonstrated in human spermatozoa that mCU blocking, through Ru360, prevents apoptosis; however, the contribution of the mCU to normal human sperm function has not been studied. Therefore, the aim of this study was to evaluate the effect of mCU blocking on human sperm function. Spermatozoa obtained from apparently healthy donors were incubated with 5 and 10 μm Ru360 for 4 h at 37 °C. Viability was assessed using propidium iodide staining; motility was determined by computer‐aided sperm analysis, adenosine triphosphate (ATP) levels using a luminescence‐based method, mitochondrial membrane potential (ΔΨm) using JC‐1 staining and reactive oxygen species (ROS) production using dihydroethidium dye. Our results show that mCU blocking significantly reduced total sperm motility and ATP levels without affecting sperm viability, ΔΨm and ROS production. In conclusion, mCU contributes to the maintenance of sperm motility and ATP levels in human spermatozoa.

[1]  M. Faiq,et al.  Oxidative stress and male infertility , 2017, Nature Reviews Urology.

[2]  M. Montero,et al.  Dynamics of mitochondrial Ca2+ uptake in MICU1-knockdown cells. , 2014, The Biochemical journal.

[3]  Peter Herman,et al.  Mitochondrial Calcium Uptake Capacity Modulates Neocortical Excitability , 2013, Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism.

[4]  M. Ghaffari,et al.  The Effect of Cigarette Smoking on Human Sperm Creatine Kinase Activity: As An ATP Buffering System in Sperm , 2013, International journal of fertility & sterility.

[5]  G. Cheng,et al.  The role of mitochondrial calcium uniporter in neuroprotection in traumatic brain injury. , 2013, Medical hypotheses.

[6]  J. Ramalho-Santos,et al.  Human Sperm Tail Proteome Suggests New Endogenous Metabolic Pathways* , 2012, Molecular & Cellular Proteomics.

[7]  H. D. Guthrie,et al.  Effects of reactive oxygen species on sperm function. , 2012, Theriogenology.

[8]  G. Sieck,et al.  Inflammation alters regional mitochondrial Ca²+ in human airway smooth muscle cells. , 2012, American journal of physiology. Cell physiology.

[9]  N. Chattipakorn,et al.  Synaptic and nonsynaptic mitochondria demonstrate a different degree of calcium-induced mitochondrial dysfunction. , 2012, Life sciences.

[10]  M. Beconi,et al.  Effect of two intracellular calcium modulators on sperm motility and heparin-induced capacitation in cryopreserved bovine spermatozoa. , 2012, Animal reproduction science.

[11]  P. Piomboni,et al.  The role of mitochondria in energy production for human sperm motility. , 2012, International journal of andrology.

[12]  A. Ferramosca,et al.  Mitochondrial respiratory efficiency is positively correlated with human sperm motility. , 2012, Urology.

[13]  T. Nishigaki,et al.  Calcium channels in the development, maturation, and function of spermatozoa. , 2011, Physiological reviews.

[14]  Carlotta Giorgi,et al.  Calcium signaling around Mitochondria Associated Membranes (MAMs) , 2011, Cell Communication and Signaling.

[15]  Paolo Bernardi,et al.  Mitochondrial permeability transition in Ca(2+)-dependent apoptosis and necrosis. , 2011, Cell calcium.

[16]  E. Carafoli.  The fateful encounter of mitochondria with calcium: how did it happen? , 2010, Biochimica et biophysica acta.

[17]  M. Chvanov,et al.  Modulation of calcium signalling by mitochondria. , 2009, Biochimica et biophysica acta.

[18]  U. Hoppe,et al.  Regulation of the Human Cardiac Mitochondrial Ca2+ Uptake by 2 Different Voltage-Gated Ca2+ Channels , 2009, Circulation.

[19]  A. Agarwal,et al.  Oxidative stress & male infertility. , 2009, The Indian journal of medical research.

[20]  Charlie Chandsawangbhuwana,et al.  Comparison of glycolysis and oxidative phosphorylation as energy sources for mammalian sperm motility, using the combination of fluorescence imaging, laser tweezers, and real‐time automated tracking and trapping , 2008, Journal of cellular physiology.

[21]  I. Bejarano,et al.  Caspase 3 activation in human spermatozoa in response to hydrogen peroxide and progesterone. , 2008, Fertility and sterility.

[22]  Claire V. Harper,et al.  [Ca2+]i signalling in sperm — making the most of what you've got , 2007, Nature Cell Biology.

[23]  Claire V. Harper,et al.  Calcium signalling in human spermatozoa: a specialized 'toolkit' of channels, transporters and stores. , 2006, Human reproduction update.

[24]  Q. Xia,et al.  Involvement of the mitochondrial calcium uniporter in cardioprotection by ischemic preconditioning. , 2006, Life sciences.

[25]  M. Duchen.  Mitochondria in health and disease: perspectives on a new mitochondrial biology. , 2004, Molecular aspects of medicine.

[26]  K. Gunter,et al.  Calcium and mitochondria , 2004, FEBS letters.

[27]  David E. Clapham,et al.  The mitochondrial calcium uniporter is a highly selective ion channel , 2004, Nature.

[28]  A. Agarwal,et al.  Alterations in mitochondria membrane potential and oxidative stress in infertile men: a prospective observational study. , 2003, Fertility and sterility.

[29]  P. Marchetti,et al.  Study of mitochondrial membrane potential, reactive oxygen species, DNA fragmentation and cell viability by flow cytometry in human sperm. , 2002, Human reproduction.

[30]  S. Sheu,et al.  Identification of a Ryanodine Receptor in Rat Heart Mitochondria* , 2001, The Journal of Biological Chemistry.

[31]  D. Bers,et al.  Oxygen-bridged Dinuclear Ruthenium Amine Complex Specifically Inhibits Ca2+ Uptake into Mitochondria in Vitroand in Situ in Single Cardiac Myocytes* , 1998, The Journal of Biological Chemistry.

[32]  V. Bindokas,et al.  Superoxide production in rat hippocampal neurons: selective imaging with hydroethidine , 1996, The Journal of neuroscience : the official journal of the Society for Neuroscience.

[33]  M. Goldberg,et al.  Mitochondrial production of reactive oxygen species in cortical neurons following exposure to N-methyl-D-aspartate , 1995, The Journal of neuroscience : the official journal of the Society for Neuroscience.

[34]  I. Reynolds,et al.  Glutamate induces the production of reactive oxygen species in cultured forebrain neurons following NMDA receptor activation , 1995, The Journal of neuroscience : the official journal of the Society for Neuroscience.

[35]  D. Clapham,et al.  Calcium signaling , 1995, Cell.

[36]  M. Clarke,et al.  Inhibition of mitochondrial calcium ion transport by an oxo-bridged dinuclear ruthenium ammine complex. , 1991, Biochemistry.

[37]  J. Mccormack,et al.  Role of calcium ions in regulation of mammalian intramitochondrial metabolism. , 1990, Physiological reviews.

[38]  G. Warnes,et al.  Improved pregnancy rate in human in vitro fertilization with the use of a medium based on the composition of human tubal fluid. , 1985, Fertility and sterility.

[39]  F. D. Vasington,et al.  Ca ion uptake by rat kidney mitochondria and its dependence on respiration and phosphorylation. , 1962, The Journal of biological chemistry.

[40]  H. DeLuca,et al.  Calcium uptake by rat kidney mitochondria. , 1961, Proceedings of the National Academy of Sciences of the United States of America.

[41]  Organización Mundial de la Salud.  WHO laboratory manual for the examination and processing of human semen , 2010 .

[42]  H. McBride,et al.  Positioning mitochondrial plasticity within cellular signaling cascades. , 2009, Biochimica et biophysica acta.