CNR - Institute of Neuroscience CNR
Institute of Neuroscience
 

Project

Neuronal calcium channels and migraine

Migraine is a common disabling brain disorder affecting more than 10% of the population. The primary cause of migraine lies in the brain, but the nature and mechanisms of the brain dysfunction(s) in migraine remain unclear and controversial, and drug therapy for preventing and treating migraine remains unsatisfactory for many patients (despite the great societal and personal costs: cf WHO ranking of migraine as one of the 20 most disabling diseases and the enormous cost to the economy: 27 billions per year in Europe). Recent findings point to cortical spreading depression (CSD) as a key player in the pathogenesis of migraine, as CSD underlies migraine aura and may also trigger the mechanisms for migraine headache (Pietrobon and Striessnig, 2003 Nat Rev Neurosci; Pietrobon, 2005 Neuroscientist). Unique insights into the pathophysiology of migraine can be gained by studying the molecular and cellular mechanisms of familial hemiplegic migraine (FHM), a monogenic subtype of migraine with aura, whose typical attacks have headache and aura symptoms similar to those of the common forms of migraine (Pietrobon, 2007 Neurotherapeutics). The aim of Pietrobon's project is to study, in particular, the mechanisms of FHM type 1 (FHM1), that is caused by missense mutations in the CACNA1A gene, encoding the pore-forming subunit of a neuronal voltage-gated Ca2+ channel (CaV2.1 or P/Q-type). CaV2.1 channels are located in somatodendritic membranes and in presynaptic terminals throughout the brain, where they play a dominant role in initiating fast synaptic transmission at most central synapses (Pietrobon, 2005 Curr Opin Neurobiol).

Relevant results of Pietrobon and collaborators:

  1. FHM1 mutations produce gain-of-function of recombinant human CaV2.1 channels, mainly due to a shift of channel activation to more negative voltages and an increase of the open probability and single channel influx over a broad voltage range (Hans et al., 1999 J Neurosci; Tottene et al., 2002 Proc Natl Acad Sci; Tottene et al., 2005 J Biol Chem).
  2. knockin (KI) mice carrying FHM1 mutations (either the mild R192Q or the severe S218L) show an increased P/Q-type Ca2+ current in cerebellar and cortical pyramidal neurons (van den Maagdenberg et al., 2004 Neuron; Tottene et al., 2009 Neuron), and an increased strength of cortical excitatory synaptic transmission due to increased action potential-evoked Ca2+ influx and increased probability of glutamate release at pyramidal cell synapses (Tottene et al., 2009 Neuron).
  3.  
  4. both the induction and the propagation of experimental CSD, elicited either by electrical stimulation in vivo or high KCl in acute slices of sensory cortex, are facilitated in FHM1 KI mice (van den Maagdenberg et al., 2004 Neuron; Tottene et al., 2009 Neuron). The extent of CSD facilitation correlates with the severity of the clinical phenotype of the FHM1 mutations. These findings support the idea that CSD plays a key role in migraine pathogenesis and suggest that FHM1 KI mice may be valuable tools to investigate the mechanisms underlying migraine and associated disorders.

The current main aim of Pietrobon's project is to investigate the cortical mechanisms that produce facilitation of CSD in FHM1 mouse models, and thus gain insights into the unknown mechanisms that lead to CSD susceptibility and initiate migraine attacks in patients, as well as into the mechanisms underlying their hypersensitivity to intense, repetitive sensory stimulation in the interictal period (Pietrobon and Striessnig, 2003). Patch-clamp recordings on cortical neurons in microculture and in acute brain slices and paired patch-clamp recordings under IR-DIC microscopy on connected neurons in acute thalamocortical slices are used to study cortical excitatory and inhibitory neurotransmission and cortical network excitability in R192Q and S218L KI mice. The in-vitro model of CSD, recently developed by the group, is used to study the mechanisms of initiation and propagation of CSD and to investigate the role of neuron-astrocyte signaling in these mechanisms. In the near future the electrophysiological measurements in cortical slices will be complemented by Ca2+ imaging experiments to follow simultaneously the activity of many cells and to investigate directly whether FHM KI mice show alterations in the spatiotemporal patterns of network activity. An important part of this project is to confirm and expand in the living brain the findings obtained in acute cortical slices (by combining two-photon Ca2+ imaging with local field potential recordings).

Recent relevant results of Pietrobon and collaborators:

 
  1. direct evidence of a causative link between enhanced glutamate release at pyramidal cell synapses and facilitation of experimental CSD: both CSD threshold and velocity in cortical slices of FHM1 KI mice become similar to those in wild-type (wt) slices when glutamate release at KI pyramidal cell synapses is reduced to wt values (Tottene et al., 2009 Neuron). This finding supports a model of CSD initiation in which release of glutamate from recurrent pyramidal cell synapses and activation of NMDA receptors are key components of the positive feedback cycle that ignites CSD.
  2. in contrast with the enhanced excitatory synaptic transmission at cortical pyramidal cell synapses, inhibitory synaptic transmission at fast-spiking interneuron synapses is not altered in FHM1 KI mice (Tottene et al., 2009 Neuron). The synapse-specific effect of FHM1 mutations points to disruption of cortical excitation-inhibition balance and neuronal hyperactivity as the basis for episodic vulnerability to CSD ignition in migraine.

Since the development of migraine pain depends on the activation and sensitization of the trigeminal nociceptive sensory fibers innervating the meninges, another aim of Pietrobon's project is to study the effect of FHM1 mutations, migraine mediators and antimigraine drugs on nociceptive trigeminal ganglion neurons (Catacuzzeno et al, 2008).

Publications

  • Tottene A, Conti R, Fabbro A, Vecchia D, Shapovalova M, Santello M, van den Maagdenberg AM, Ferrari MD, Pietrobon D (2009) Enhanced excitatory transmission at cortical synapses as the basis for facilitated spreading depression in Ca(v)2.1 knockin migraine mice. Neuron 61:762-73.
  • Catterall WA, Dib-Hajj S, Meisler MH, Pietrobon D (2008) Inherited neuronal ion channelopathies: new windows on complex neurological diseases. J. Neurosci. 28:11768-77.
  • Luvisetto S, Marinelli S, Panasiti MS, D'Amato FR, Fletcher CF, Pavone F, Pietrobon D (2006) Pain sensitivity in mice lacking the Ca(v)2.1alpha1 subunit of P/Q-type Ca2+ channels. Neuroscience 142:823-32.
  • Tottene A, Pivotto F, Fellin T, Cesetti T, van den Maagdenberg AM, Pietrobon D (2005) Specific kinetic alterations of human CaV2.1 calcium channels produced by mutation S218L causing familial hemiplegic migraine and delayed cerebral edema and coma after minor head trauma. J. Biol. Chem. 280:17678-86.
  • Fellin T, Luvisetto S, Spagnolo M, Pietrobon D (2004) Modal gating of human CaV2.1 (P/Q-type) calcium channels: II. the b mode and reversible uncoupling of inactivation. J. Gen. Physiol. 124:463-74.
  • Luvisetto S, Fellin T, Spagnolo M, Hivert B, Brust PF, Harpold MM, Stauderman KA, Williams ME, Pietrobon D (2004) Modal gating of human CaV2.1 (P/Q-type) calcium channels: I. The slow and the fast gating modes and their modulation by beta subunits. J. Gen. Physiol. 124:445-61.
  • van den Maagdenberg AM, Pietrobon D, Pizzorusso T, Kaja S, Broos LA, Cesetti T, van de Ven RC, Tottene A, van der Kaa J, Plomp JJ, Frants RR, Ferrari MD (2004) A Cacna1a knockin migraine mouse model with increased susceptibility to cortical spreading depression. Neuron 41:701-10.
  • Fletcher CF, Tottene A, Lennon VA, Wilson SM, Dubel SJ, Paylor R, Hosford DA, Tessarollo L, McEnery MW, Pietrobon D, Copeland NG, Jenkins NA (2001) Dystonia and cerebellar atrophy in Cacna1a null mice lacking P/Q calcium channel activity. FASEB J. 15:1288-90.
  • Guida S, Trettel F, Pagnutti S, Mantuano E, Tottene A, Veneziano L, Fellin T, Spadaro M, Stauderman K, Williams M, Volsen S, Ophoff R, Frants R, Jodice C, Frontali M, Pietrobon D (2001) Complete loss of P/Q calcium channel activity caused by a CACNA1A missense mutation carried by patients with episodic ataxia type 2. Am. J. Hum. Genet. 68:759-64.
  • Hans M, Luvisetto S, Williams ME, Spagnolo M, Urrutia A, Tottene A, Brust PF, Johnson EC, Harpold MM, Stauderman KA, Pietrobon D (1999) Functional consequences of mutations in the human alpha1A calcium channel subunit linked to familial hemiplegic migraine. J. Neurosci. 19:1610-9.

Grants

Telethon grant nu. GGP06234:
Functional consequences of mutations associated to familial hemiplegic migraine type 1 and migraine mechanisms

PRIN 2007:
Neuronal calcium channels and migraine

Cariparo grant 2009:
Calcium signalling in health and disease

Strategic Project of the University of Padova 2009:
Physiopathology of signalling in neuronal tissues: an in vivo approach

Collaborations

  • Tommaso Pizzorusso, University of Firenze and CNR Institute of Neuroscience, Pisa, Italy.
  • Fabio Franciolini, University of Perugia, Italy.
  • Giorgio Carmignoto and Tullio Pozzan, CNR Institute of Neuroscience, Padova, Italy.
  • Arn van den Maagdenberg and Michel Ferrari, Leiden University Medical Center, The Netherlands.
  • Joerg Striessnig, University of Innsbruck, Austria.
  • Terrance Snutch, niversity of British Columbia, Canada.

 

PI photo

Daniela Pietrobon

Contact information

email  E-mail

email  049 8276052

Participating staff

Rossella Conti
Assistant Professor

Angelita Tottene
Technician

Alessandra Fabbro
Post-doct

Dania Vecchia
PhD student

Michele Sessolo
PhD student

Andrea Urbani
PhD student

Luigi Sforna
Research Fellow