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Analysis of Calcium Ion homeostasis and mitochondrial function in cerebellar granule cells of adult Cav 2.1 Calcium Ion channel mutant mice

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Abstract

Cav 2.1 voltage-gated calcium channels (VGCC) are highly expressed by cerebellar neurons, and their dysfunction is linked to human disorders including familial hemiplegic migraine, episodic ataxia type 2 and spinocerebellar ataxia type 6. Altered calcium homeostasis, due to dysfunctional Cav 2.1 VGCC can severely affect mitochondrial function, eventually leading to neuronal cell death. We study leaner and tottering mice, which carry autosomal recessive mutations in the gene coding for the α1A pore-forming subunit of Cav 2.1 VGCC. Both leaner and tottering mice exhibit cerebellar ataxia and epilepsy. Excessive leaner cerebellar granule cell (CGC) death starts soon after postnatal day 10, but it is not known whether the degree of CGC cell death observed in adult leaner mice is significantly different from wild type mice. We used Fluoro-Jade and TUNEL staining to quantify apoptotic cell death in leaner and wild type CGC. We investigated calcium homeostasis, mitochondrial function and generation of reactive oxygen species (ROS) in isolated CGC, using indicator dyes Fura-2AM, TMRM and CMH2DCFDA, respectively. We observed a small but significant increase in number of apoptotic adult leaner CGC. Calcium homeostasis and mitochondrial function also were altered in leaner CGC. However, no significant differences in ROS levels were observed. It is possible that CGC death in leaner mice may be related to mitochondrial dysfunction but may not be directly related to decreased basal intracellular calcium.

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References

  • Adams JM and S Cory (1998) The Bcl-2 protein family: arbiters of cell survival.Science 281(5381), 1322–1326.

    Article  PubMed  CAS  Google Scholar 

  • Afzal M, S Matsugo, M Sasai, B Xu, K Aoyama and T Takeuchi (2003) Method to overcome photoreaction, a serious drawback to the use of dichlorofluorescin in evaluation of reactive oxygen species.Biochem. Biophys. Res. Commun. 304(4), 619–624.

    Article  PubMed  CAS  Google Scholar 

  • Arundine M and M Tymianski (2003) Molecular mechanisms of calcium-dependent neurodegeneration in excitotoxicity.Cell Calcium 34(4-5), 325–337.

    Article  PubMed  CAS  Google Scholar 

  • Barclay J and M Rees (1999) Mouse models of spike-wave epilepsy.Epilepsia 40 Suppl. 3, 17–22.

    Article  PubMed  CAS  Google Scholar 

  • Bellum S, B Bawa, KA Thuett, G Stoica and LC Abbott (2007) Changes in biochemical processes in cerebellar granule cells of mice exposed to methylmercury.Int. J. Toxicol. 26(3), 261–269.

    Article  PubMed  CAS  Google Scholar 

  • Blanchard KT, EK Allard and K Boekelheide (1996) Fate of germ cells in 2,5-hexanedione-induced testicular injury.I. Apoptosis is the mechanism of germ cell death.Toxicol. Appl. Pharmacol.137, 141–148.

    Article  PubMed  CAS  Google Scholar 

  • Boldyrev A, A Koudinov, T Berezov and DO Carpenter (2004) Amyloid-β induced cell death is independent of free radicals.J. Alzheimer. Dis. 6(6), 633–638; discussion 673-681.

    CAS  Google Scholar 

  • Budd SL and DG Nicholls (1996) A reevaluation of the role of mitochondria in neuronal Ca2+ homeostasis.J. Neurochem. 66, 403–411.

    Article  PubMed  CAS  Google Scholar 

  • Butterfield DA, A Castegna, J Drake, G Scapagnini and V Calabrese (2002) Vitamin E and neurodegenerative disorders associated with oxidative stress.Nutr. Neurosci. 5(4), 229–239.

    Article  PubMed  CAS  Google Scholar 

  • Canzoniero LMT and BJ Snider (2005) Calcium in Alzheimer’s disease pathogenesis: too much, too little or in the wrong place?J. Alzheimer. Dis. 8(2), 147–154; discussion 209-115.

    CAS  Google Scholar 

  • Cooper CE, NA Davies, M Psychoulis, L Canevari, TE Bates, MS Dobbie, CS Casley and MA Sharpe (2003) Nitric oxide and peroxynitrite cause irreversible increases in the K(m) for oxygen of mitochondrial cytochrome oxidase:in vitro andin vivo studies.Biochim. Biophys. Acta 1607(1), 27–34.

    Article  PubMed  CAS  Google Scholar 

  • Dove LS, LC Abbott and WH Griffith (1998) Whole-cell and single-channel analysis of P-type calcium currents in cerebellar Purkinje cells of leaner mutant mice.J. Neurosci. 18, 7687–7699.

    PubMed  CAS  Google Scholar 

  • Dove LS, SS Nahm, D Murchison, LC Abbott and WH Griffith (2000) Altered calcium homeostasis in cerebellar Purkinje cells of leaner mutant mice.J. Neurophysiol. 84(1), 513–524.

    PubMed  CAS  Google Scholar 

  • Du C, M Fang, Y Li, L Li and X Wang (2000) Smac, a mitochondrial protein that promotes cytochrome c-dependent caspase activation by eliminating IAP inhibition.Cell 102(1), 33–42.

    Article  PubMed  CAS  Google Scholar 

  • Ducros A, C Denier, A Joutel, K Vahedi, A Michel, F Darcel, M Madigand, D Guerouaou, F Tison, J Julien, E Hirsch, F Chedru, C Bisgard, G Lucotte, P Despres, C Billard, MA Barthez, G Ponsot, MG Bousser and E Tournier-Lasserve (1999) Recurrence of the T666M calcium channel CACNA1A gene mutation in familial hemiplegic migraine with progressive cerebellar ataxia.Am. J. Hum. Genet. 64(1), 89–98.

    Article  PubMed  CAS  Google Scholar 

  • Enari M, H Sakahira, H Yokoyama, K Okawa, A Iwamatsu and S Nagata (1998) A caspase-activated DNase that degrades DNA during apoptosis, and its inhibitor ICAD.[see comment] [erratumappearsinNature 1998 May28:393(6683):396].Nature 391(6662), 43–50.

    Article  PubMed  CAS  Google Scholar 

  • Ertel EA, KP Campbell, MM Harpold, F Hofmann, Y Mori, E Perez-Reyes, A Schwartz, TP Snutch, T Tanabe, L Birnbaumer,RWTsienandWACatterall(2000)Nomenclature of voltage-gated calcium channels. [comment].Neuron 25(3), 533–535.

    Article  PubMed  CAS  Google Scholar 

  • Evans GJ and MA Cousin (2007) Simultaneous monitoring of three key neuronal functions in primary neuronal cultures.J. Neurosci. Meth. 160(2), 197–205.

    Article  Google Scholar 

  • Facheris M, S Beretta and C Ferrarese (2004) Peripheral markers of oxidative stress and excitotoxicity in neurodegenerative disorders: tools for diagnosis and therapy?J. Alzheimer. Dis. 6(2), 177–184.

    CAS  Google Scholar 

  • Farkas DL, MD Wei, P Febbroriello, JH Carson and LM Loew (1989) Simultaneous imaging of cell and mitochondrial membrane potentials.Biophys. J. 56(6), 1053–1069.

    Article  PubMed  CAS  Google Scholar 

  • Fletcher CF, CM Lutz, TN O’Sullivan, JD Shaughnessy Jr, R Hawkes, WN Frankel, NG Copeland and NA Jenkins (1996) Absence epilepsy in tottering mutant mice is associated with calcium channel defects.Cell 87(4), 607–617.

    Article  PubMed  CAS  Google Scholar 

  • Floyd RA and K Hensley (2002) Oxidative stress in brain aging. Implications for therapeutics of neurodegenerative diseases.Neurobiol. Aging 23(5), 795–807.

    Article  PubMed  CAS  Google Scholar 

  • Frank TC, MC Nunley, HD Sons, R Ramon and LC Abbott (2003) Fluoro-jade identification of cerebellar granule cell and purkinje cell death in the α1A calcium ion channel mutant mouse, leaner.Neuroscience 118(3), 667–680.

    Article  PubMed  CAS  Google Scholar 

  • Galli C, O Meucci, A Scorziello, TM Werge, P Calissano and G Schettini (1995) Apoptosis in cerebellar granule cells is blocked by high KCl, forskolin, and IGF-1 through distinct mechanisms of action: the involvement of intracellular calcium and RNA synthesis.J. Neurosci. 15(2), 1172–1179.

    PubMed  CAS  Google Scholar 

  • Grynkiewicz G, M Poenie and RY Tsien (1985) A new generation of Ca2+ indicators with greatly improved fluorescence properties.J. Biol. Chem. 260, 3440–3450.

    PubMed  CAS  Google Scholar 

  • Herrup K and B Kuemerle (1997) The compartmentalization of the cerebellum.Ann. Rev. Neurosci. 20, 61–90.

    Article  PubMed  CAS  Google Scholar 

  • Herrup K and SL Wilczynski (1982) Cerebellar cell degeneration in the leaner mutant mouse.Neuroscience 7, 2185–2196.

    Article  PubMed  CAS  Google Scholar 

  • Ichas F and JP Mazat (1998) From calcium signaling to cell death: two conformations for the mitochondrial permeability transition pore. Switching from low- to high-conductance state.Biochim. Biophys. Acta 1366(1-2), 33–50.

    Article  PubMed  CAS  Google Scholar 

  • Ichikawa D, A Tabuchi, A Taoka, T Tsuchiya and M Tsuda (1998) Attenuation of cell death mediated by membrane depolarization different from that by exogenous BDNF in cultured mouse cerebellar granule cells.Brain Res. Mol. Brain Res. 56(1-2), 218–226.

    Article  PubMed  CAS  Google Scholar 

  • Isaacs KR and LC Abbott (1995) Cerebellar volume decreases in the tottering mouse are specific to the molecular layer.Brain Res. Bull. 36(3), 309–314.

    Article  PubMed  CAS  Google Scholar 

  • Jenner P (2003) Oxidative stress in Parkinson’s disease.Ann. Neurol. 53 Suppl. 3, S26-S36; discussion S36-S38.

    Article  PubMed  CAS  Google Scholar 

  • Jouvenceau A, LH Eunson, A Spauschus, V Ramesh, SM Zuberi, DM Kullmann and MG Hanna (2001) Human epilepsy associated with dysfunction of the brain P/Q-type calcium channel.[see comment].Lancet 358(9284), 801–807.

    Article  PubMed  CAS  Google Scholar 

  • Julian D, KL April, S Patel, JR Stein and SE Wohlgemuth (2005) Mitochondrial depolarization following hydrogen sulfide exposure in erythrocytes from a sulfide-tolerant marine invertebrate.J. Exp. Biol. 208(Pt. 21), 4109–4122.

    Article  PubMed  CAS  Google Scholar 

  • Klockgether T and B Evert (1998) Genes involved in hereditary ataxias.Trends Neurosci. 21(9), 413–418.

    Article  PubMed  CAS  Google Scholar 

  • Kostopoulos GK (1992) The tottering mouse: a critical review of its usefulness in the study of the neuronal mechanisms underlying epilepsy.J. Neural Transm. Suppl.35, 21–36.

    Google Scholar 

  • Kume T, R Taguchi, H Katsuki, M Akao, H Sugimoto, S Kaneko and A Akaike (2006) Serofendic acid, a neuroprotective substance derived from fetal calf serum, inhibits mitochondrial membrane depolarization and caspase-3 activation.Eur. J. Pharmacol. 542(1-3), 69–76.

    Article  PubMed  CAS  Google Scholar 

  • Lau FC (1999) Apoptosis, reduced intracellular free calcium level and altered gene expression in the cerebellum of the leaner mutant mouse. Dissertation. College Station, TX: Texas A&M University.

    Google Scholar 

  • Lau FC, LC Abbott, IJ Rhyu, DS Kim and H Chin (1998) Expression of calcium channel α1A mRNA and protein in the leaner mouse (tg 1a/tg 1a) cerebellum.Brain Res. Mol. Brain Res. 59(1), 93–99.

    Article  PubMed  CAS  Google Scholar 

  • Lau FC, TC Frank, S-S Nahm, G Stoica and LC Abbott (2004) Postnatal apoptosis in cerebellar granule cells of homozygous leaner (tg 1a/tg 1a) mice.Neurotox. Res. 6(4), 267–280.

    Article  PubMed  Google Scholar 

  • Lee J, JH Richburg, SC Younkin and K Boekelheide (1997) The Fas system is a key regulator of germ cell apoptosis in the testis.Endocrinology 138(5), 2081–2088.

    Article  PubMed  CAS  Google Scholar 

  • Liu X, CN Kim, J Yang, R Jemmerson and X Wang (1996) Induction of apoptotic program in cell-free extracts: requirement for dATP and cytochromec.Cell 86(1), 147–157.

    Article  PubMed  CAS  Google Scholar 

  • Lorenzon NM, CM Lutz, WN Frankel and KG Beam (1998) Altered calcium channel currents in Purkinje cells of the neurological mutant mouse leaner.J. Neurosci. 18(12), 4482–4489.

    PubMed  CAS  Google Scholar 

  • Migheli A, P Cavalla, S Marino and D Schiffer (1994) A study of apoptosis in normal and pathologic nervous tissue afterin situ end-labeling of DNA strand breaks.J. Neuropathol. Exp. Neurol. 53(6), 606–616.

    Article  PubMed  CAS  Google Scholar 

  • Miller RJ (1991) The control of neuronal Ca2+ homeostasis.Prog. Neurobiol. 37(3), 255–285.

    Article  PubMed  CAS  Google Scholar 

  • Mironov SL (1995) Plasmalemmal and intracellular Ca2+ pumps as main determinants of slow Ca2+ buffering in rat hippocampal neurones.Neuropharmacology 34(9), 1123–1132.

    Article  PubMed  CAS  Google Scholar 

  • Missiaen L, W Robberecht, L van den Bosch, G Callewaert, JB Parys, F Wuytack, L Raeymaekers, B Nilius, J Eggermont and H De Smedt (2000) Abnormal intracellular Ca2+ homeostasis and disease.Cell Calcium 28(1), 1–21.

    Article  PubMed  CAS  Google Scholar 

  • Mullen RJ, CR Buck and AM Smith (1992) NeuN, a neuronal specific nuclear protein in vertebrates.Development 116, 201–211.

    PubMed  CAS  Google Scholar 

  • Murchison D, LS Dove, LC Abbott and WH Griffith (2002) Homeostatic compensation maintains Ca2+ signaling functions in Purkinje neurons in the leaner mutant mouse.Cerebellum 1(2), 119–127.

    Article  PubMed  CAS  Google Scholar 

  • Myhre O, JM Andersen, H Aarnes and F Fonnum (2003) Evaluation of the probes 2’,7’-dichlorofluorescin diacetate, luminol, and lucigenin as indicators of reactive species formation.Biochem. Pharmacol. 65(10), 1575–1582.

    Article  PubMed  CAS  Google Scholar 

  • Nahm S-S (2002) Analysis of gene and protein expression related to cerebellar neurodegeneration in the calcium channel mutant mouse, leaner. Dissertation. College Station, TX: Texas A&M University.

    Google Scholar 

  • Nahm S-S, D-J Tomlinson and LC Abbott (2002) Decreased calretinin expression in cerebellar granule cells in the leaner mouse.J. Neurobiol. 51(4), 313–322.

    Article  PubMed  CAS  Google Scholar 

  • Newmeyer DD and S Ferguson-Miller (2003) Mitochondria: releasing power for life and unleashing the machineries of death. [erratum appears inCell 2003 Mar 21;(112)6, 873].Cell 112(4), 481–490.

    Article  PubMed  CAS  Google Scholar 

  • Nicholls DG and MW Ward (2000) Mitochondrial membrane potential and neuronal glutamate excitotoxicity: mortality and millivolts.Trends Neurosci. 23(4), 166–174.

    Article  PubMed  CAS  Google Scholar 

  • Oberdoerster J (2001) Isolation of cerebellar granule cells from Neonatal rats, In:Current Protocols in Toxicology (Maines MD, LG Costa, E Hodgson, DJ Reed and IG Sipes, Eds.) (John Wiley and Sons:Hoboken, NJ), pp 12.7.1–12.7.10.

    Google Scholar 

  • Ophoff RA, GM Terwindt, MN Vergouwe, R van Eijk, PJ Oefner, SM Hoffman, JE Lamerdin, HW Mohrenweiser, DE Bulman, M Ferrari, J Haan, D Lindhout, GJ van Ommen, MH Hofker, MD Ferrari and RR Frants (1996) Familial hemiplegic migraine and episodic ataxia type-2 are caused by mutations in the Ca2+ channel geneCACNL1A4.Cell 87, 543–552.

    Article  PubMed  CAS  Google Scholar 

  • Petit JM, A Maftah, MH Ratinaud and R Julien (1992) 10N-nonyl-Acridine orange interacts with cardiolipin and allows the quantification of this phospholipid in isolated mitochondria.Eur. J. Biochem. 209, 267–273.

    Article  PubMed  CAS  Google Scholar 

  • Petit JM, O Huet, PF Gallet, A Maftah, MH Ratinaud and R Julien (1994) Direct analysis and significance of cardiolipin transverse distribution in mitochondrial inner membranes.Eur. J. Biochem. 220, 871–879.

    Article  PubMed  CAS  Google Scholar 

  • Pietrobon D (2002) Calcium channels and channelopathies of the central nervous system.Mol. Neurobiol. 25(1), 31–50.

    Article  PubMed  CAS  Google Scholar 

  • Rhyu IJ, S-S Nahm, SJ Hwang, H Kim, Y-S Suh, S-I Oda, TC Frank and LC Abbott (2003) Altered neuronal nitric oxide synthase expression in the cerebellum of calcium channel mutant mice.Brain Res. 977(2), 129–140.

    Article  PubMed  CAS  Google Scholar 

  • Russell JW, KA Sullivan, AJ Windebank, DN Herrmann and EL Feldman (1999) Neurons undergo apoptosis in animal and cell culture models of diabetes.Neurobiol. Dis. 6(5), 347–363.

    Article  PubMed  CAS  Google Scholar 

  • Sarnat HB, D Nochlin and DE Born (1998) Neuronal nuclear antigen (NeuN): a marker of neuronal maturation in early human fetal nervous system.Brain Dev. 20(2), 88–94.

    Article  PubMed  CAS  Google Scholar 

  • Sastry PS and KS Rao (2000) Apoptosis and the nervous system.J. Neurochem. 74, 1–20.

    Article  PubMed  CAS  Google Scholar 

  • Sattler R and M Tymianski (2001) Molecular mechanisms of glutamate receptor-mediated excitotoxic neuronal cell death.Mol. Neurobiol. 24(1-3), 107–129.

    Article  PubMed  CAS  Google Scholar 

  • Schinder AF, EC Olson, NC Spitzer and M Montal (1996) Mitochondrial dysfunction is a primary event in glutamate neurotoxicity.J. Neurosci. 16, 6125–6133.

    PubMed  CAS  Google Scholar 

  • Schmued LC, C Albertson and W Slikker Jr (1997) Fluoro Jade: a novel fluorochrome for the sensitive and reliable histochemical localization of neuronal degeneration.Brain Res. 751, 37–46.

    Article  PubMed  CAS  Google Scholar 

  • Schulz JB, M Weller and T Klockgether (1996) Potassium deprivation-induced apoptosis of cerebellar granule neurons: a sequential requirement for new mRNA and protein synthesis, ICE-like protease activity, and reactive oxygen species.J. Neurosci. 16, 4696–4706.

    PubMed  CAS  Google Scholar 

  • Slemmer JE, CI De Zeeuw and JT Weber (2005) Don’t get too excited: mechanisms of glutamate-mediated Purkinje cell death.Prog. Brain Res. 148, 367–390.

    Article  PubMed  CAS  Google Scholar 

  • Stys PK, SG Waxman and BR Ransom (1991) Na+-Ca2+ exchanger mediates Ca2+ influx during anoxia in mammalian central nervous system white matter.Ann. Neurol. 30, 375–380.

    Article  PubMed  CAS  Google Scholar 

  • Tabuchi A, K Funaji, J Nakatsubo, M Fukuchi, T Tsuchiya and M Tsuda (2003) Inactivation of aconitase during the apoptosis of mouse cerebellar granule neurons induced by a deprivation of membrane depolarization.J. Neurosci. Res. 71(4), 504–515.

    Article  PubMed  CAS  Google Scholar 

  • Tan Y, C-H Chen, D Lawrence and DO Carpenter (2004) Ortho-substituted PCBs kill cells by altering membrane structure.Toxicol. Sci. 80(1), 54–59.

    Article  PubMed  CAS  Google Scholar 

  • Van den Hoek TL, C Li, Z Shao, PT Schumacker and LB Becker (1997) Significant levels of oxidants are generated by isolated cardiomyocytes during ischemia prior to reperfusion.J. Mol. Cell. Cardiol. 29, 2571–2583.

    Article  Google Scholar 

  • Vergun O, AI Sobolevsky, MV Yelshansky, J Keelan, BI Khodorov and MR Duchen (2001) Exploration of the role of reactive oxygen species in glutamate neurotoxicity in rat hippocampal neurones in culture.J. Physiol. 531(Pt. 1), 147–163.

    Article  PubMed  CAS  Google Scholar 

  • Wallig MA, CM Chan and NA Gillet (2002) Specific methods for detection and quantification of apoptosis in tissue section, In:Apoptosis Methods in Pharmacology and Toxicology. Approaches to Measurement and Quantification (Davis MA, Ed.) (Humana Press:Totowa, NJ, USA), pp 59–76.

    Chapter  Google Scholar 

  • Weber JT (2004) Calcium homeostasis following traumatic neuronal injury.Curr. Neurovasc. Res. 1(2), 151–171.

    Article  PubMed  Google Scholar 

  • Westenbroek RE, T Sakurai, EM Elliott, JW Hell, TV Starr, TP Snutch and WA Catterall (1995) Immunochemical identification and subcellular distribution of the α1A subunits of brain calcium channels.J. Neurosci. 15, 6403–6418.

    PubMed  CAS  Google Scholar 

  • Weyer A and K Schilling (2003) Developmental and cell typespecific expression of the neuronal marker NeuN in the murine cerebellum.J. Neurosci. Res. 73(3), 400–409.

    Article  PubMed  CAS  Google Scholar 

  • Xie Z, P Kometiani, J Liu, J Li, JI Shapiro and A Askari (1999) Intracellular reactive oxygen species mediate the linkage of Na+/K+-ATPase to hypertrophy and its marker genes in cardiac myocytes.J. Biol. Chem. 274(27), 19323–19328.

    Article  PubMed  CAS  Google Scholar 

  • Yoon WJ, SJ Won, BR Ryu and BJ Gwag (2003) Blockade of ionotropic glutamate receptors produces neuronal apoptosis through the Bax-cytochrome c-caspase pathway: the causative role of Ca2+ deficiency.J. Neurochem. 85(2), 525–533.

    Article  PubMed  CAS  Google Scholar 

  • Yuan J, M Lipinski and A Degterev (2003) Diversity in the mechanisms of neuronal cell death.Neuron 40(2), 401–413.

    Article  PubMed  CAS  Google Scholar 

  • Yuan J and BA Yankner (2000) Apoptosis in the nervous system.Nature 407(6805), 802–809.

    Article  PubMed  CAS  Google Scholar 

  • Zhao K, G Luo, S Giannelli and HH Szeto (2005) Mitochondriatargeted peptide prevents mitochondrial depolarization and apoptosis induced by tert-butyl hydroperoxide in neuronal cell lines.Biochem. Pharmacol. 70(12), 1796–1806.

    Article  PubMed  CAS  Google Scholar 

  • Zorov DB, SY Bannikova, VV Belousov, MY Vyssokikh, LD Zorova, NK Isaev, BF Krasnikov and EY Plotnikov (2005) Reactive oxygen and nitrogen species: friends or foes?Biochemistry-Russia 70(2), 215–221.

    CAS  Google Scholar 

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Bawa, B., Abbott, L.C. Analysis of Calcium Ion homeostasis and mitochondrial function in cerebellar granule cells of adult Cav 2.1 Calcium Ion channel mutant mice. neurotox res 13, 1–18 (2008). https://doi.org/10.1007/BF03033363

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