Title: IMAGING CELLULAR MECHANISMS OF MIGRAINE
1IMAGING CELLULAR MECHANISMS OF MIGRAINE
Andrew Charles, M.D. Professor Director, Headache
Research and Treatment Program Department of
Neurology UCLA School of Medicine
2Bilateral Spreading Cerebral Hypoperfusion during
Spontaneous Migraine HeadacheRoger P. Woods,
Marco Iacoboni, and John C. MazziottaNEJM
3311689-92, 1994
3(No Transcript)
4Oleson, et al. 1981
Woods et al., 1994
Hadjikhani et al., 2001
Cao et al., 1999
5CELLULAR IMAGING MODALITIES FOR INVESTIGATION OF
MIGRAINE
- Fluorescence imaging
- Cells are loaded or labeled with indicators that
change their fluorescence intensity in response
to changes in cellular characteristics (calcium,
other ions, membrane potential, cellular
messengers) - Optical intrinsic signal imaging
- Brain tissue is directly illuminated and light
that is either reflected or transmitted is
recorded. Recording at different wavelengths
emphasizes different components of signal (blood
volume, hemoglobin oxygenation, change in
extracellular space, ? mitochondrial swelling,
etc.)
6POTENTIAL CELLULAR SUBSTRATES FOR PROPAGATED
CORTICAL PHENOMENA IN MIGRAINE
- NEURONS
- GLIAL CELLS
- ASTROCYTES, OLIGODENDROCYTES, MICROGLIA
- VASCULAR CELLS
- ENDOTHELIAL CELLS, PERICYTES, SMOOTH MUSCLE CELLS
7FLUORESCENCE IMAGING OF INTRACELLULAR
Ca2 Cortical Neuronal Culture
8ASTROCYTES
- OUTNUMBER NEURONS BY UP TO 5x
- RATIO OF NEURONS TO ASTROCYTES DIFFERENT IN
DIFFERENT BRAIN REGIONS (E.G. GREATEST IN
OCCIPTIAL CORTEX) - CLOSE RELATIONSHIP WITH SYNAPSE AND WITH
VASCULATURE - RECEPTORS FOR A VARIETY OF NEUROTRANSMITTER
RECEPTORS - CAPABLE OF EXTENSIVE INTERCELLULAR SIGNALING
9Intercellular Calcium Wave Mixed Glial Culture
Real Time
10Neurotransmitters
Mechanical Stimulation
Low Extracellular Ca
2
Ca
2
PLC
Ca
2
V
D
V
D
D
V
D
V
m
m
m
m
IP
IP
IP
3
3
PIP
3
2
IP
Ca
2
IP
3
3
Ca
2
Ca
2
Ca
2
Ca
2
Ca
2
?
Ca
2
Ca
2
Ca
2
Ca
2
Ca
2
Ca
2
Ca
2
Ca
2
Ca
2
Ca
2
Ca
2
Ca
2
Ca
2
A MODEL FOR GLIAL CALCIUM WAVES
11AN EXTRACELLULAR MESSENGER
12GLIAL CALCIUM WAVES ARE MEDIATED BY RELEASE OF ATP
- LUCIFERASE ASSAY DEMONSTRATES RELEASE OF ATP
- PURINERGIC RECEPTOR ANTAGONISTS BLOCK CALCIUM
WAVES - APYRASE (ATP DEGRADING ENZYME) BLOCKS CALCIUM
WAVES - DETECTOR CELLS EXPRESSING PURINERGIC RECEPTORS
RESPOND TO GLIAL CALCIUM WAVES
13GLIAL CALCIUM WAVES
- ASSOCIATED WITH ACTIVE RELEASE OF
- ATP
- GLUTAMATE
- K
- EICOSANOIDS
- LACTATE
- MODULATE
- NEURONAL ACTIVITY VIA TRANSMITTER RELEASE (Araque
et al., 1999 Fellin et al., 2004) - NEURONAL/VASCULAR METABOLISM VIA LACTATE RELEASE
(Paemeleire, 2000 Bernadelli et al., 2004) - VASCULAR TONE VIA ARACHIDONIC ACID, EICOSANOID
RELEASE, AND ATP (?) RELEASE (Zonta et al., 2003
Filosa et al., 2004 Mulligan et al., 2004)
14.
.
Endothelial Cell
Endothelial Cell
Meningeal
Cell
Meningeal
Cell
Neurons
Neurons
Glutamate
ATP Adenosine
ATP Adenosine
Neurotransmitters
Neurotransmitters
2
Ca
Ca
K
-
-
ATP
ATP
Mechanical stimulus
Mechanical stimulus
Mg
2
Mg
DAG
PLC
Glutamate
PLC
ATP
Glutamate
ATP
PLC
K
PLC
PIP
PIP
IP
IP
2
2
2
2
Ca
Ca
3
3
IP
IP
PIP
PIP
3
IP
3
IP
2
2
3
3
Connexin Hemichannel
Ca
2
Ca
2
Ca
2
Ca
2
Ca
2
Ca
2
2
2
Ca
Ca
Ca
2
Ca
2
?
?
Ca
2
Ca
2
Ca
2
Ca
2
Ca
2
Ca
2
2
2
2
2
Ca
Ca
Ca
Ca
2
2
Ca
Ca
Ca
2
Ca
2
Ca
2
Ca
2
ASTROCYTE
ASTROCYTE
ASTROCYTE
ASTROCYTE
15Glial Ca2 Waves in Hippocampal Slice
Culture Time Lapse Sequence of 5 Minute Recording
16DO GLIAL WAVES PLAY A ROLE IN MIGRAINE?
- SIMILAR TEMPORAL AND SPATIAL CHARACTERISTICS AS
MIGRAINE EVENTS - ASSOCIATED RELEASE OF ATP, GLUTAMATE, AND OTHER
NEURO- AND VASO-ACTIVE SUBSTANCES - ASSOCIATED CHANGES IN EXTRACELLULAR IONIC
COMPOSITION - INTIMATE SPATIAL RELATIONSHIPS WITH SYNAPSE AND
VASCULATURE - COULD EXPLAIN DRAMATIC PROPAGATION WITH
RELATIVELY MILD NEUROLOGICAL SYMPTOMS
17ATP RELEASED BY GLIAL CELLS IS RAPIDLY METABOLIZED
TO ADENOSINE, WHICH INHIBITS NEURONS
18ADENOSINE CAUSES RAPID AND REVERSIBLE
INHIBTION OF NEURONAL ACTIVITY
19ADENOSINE INHIBITS SPONTANEOUS ACTIVITY IN
CORTICAL NEURONS
20ADENOSINE AS A NEURO-MODULATOR AND VASO-MODULATOR
- MULTIPLE RECEPTOR SUBTYPES WITH CELL-SPECIFIC
ACTIONS - PRIMARILY INHIBITORY EFFECT ON NEURONS
- MAY ACTIVATE GLIAL CELLS
- DILATES PIAL BLOOD VESSELS
- CAFFEINE IS AN ADENOSINE RECEPTOR ANTAGONIST
21HYPOTHESIS
GLIAL CALCIUM WAVES MEDIATE PROPAGATED CORTICAL
PHENOMENA IN MIGRAINE VIA RELEASE OF ATP WHICH IS
METABOLIZED TO ADENOSINE
22(No Transcript)
23GLIAL CALCIUM WAVES AND SPREADING DEPRESSION
- GLIAL CALCIUM WAVES ARE OBSERVED IN CONJUNCTION
WITH ELECTROPHYSIOLOGICAL SPREADING DEPRESSION IN
BRAIN SLICES (Basarsky et al., 1998 Kunkler et
al., 1998 Peters et al., 2003) - GLIAL CALCIUM WAVES CAN BE DISSOCIATED FROM
SPREADING DEPRESSION IN THESE PREPARATIONS - RELATED BUT DISTINCT PHENOMENA WITH INDEPENDENT
MECHANISMS OF PROPAGATION
24Luis Beltran-Parrazal
K.C. Brennan
Calcium imaging Electrophysiology
OIS Imaging and Electrophysiology Cortical
spreading depression
25OPTICAL INTRINSIC SIGNAL SPREADING DEPRESSION
EVOKED BY KCl PULSE RAT CORTEX (Compressed 5 min
recording)
26Regions of interest
27Arteriolar dilatation precedes parenchymal onset
of CSD
28OIS IMAGING OF CSD
- PROPAGATED WAVE OF CHANGE IN REFLECTANCE WITH AT
LEAST 4 PHASES - IMAGING AT DIFFERENT WAVELENGTHS EMPHASIZES
DIFFERENT CELLULAR/VASCULAR PHENOMENA - MULTIPHASIC ARTERIAL RESPONSE THAT MAY PRECEDE
WAVE OF OPTICAL SIGNAL
29HYPOTHESIS
GLIAL CALCIUM WAVES MEDIATE PROPAGATED CORTICAL
PHENOMENA IN MIGRAINE VIA RELEASE OF ATP,
GLUTAMATE, AND K
30Glial Calcium Waves In Hippocampal Slice
Recurrent CSD Evoked By KCL Crystal
SIMILAR TEMPORAL AND SPATIAL PATTERNS OF GLIAL
CALCIUM WAVES AND OIS SIGNAL OF CSD
31CONNEXIN CHANNEL BLOCKER FLUFENAMIC ACID INHIBITS
GLIAL Ca2 WAVES AND ATP RELEASE
IN 50 mM FLUFENAMIC ACID
CONTROL
32FLUFENAMIC ACID REVERSIBLY INHIBITS SPREADING
DEPRESSION
33Control
CGS 15943 10 mM
AN ADENOSINE RECEPTOR ANTAGONIST (CGS15943)
INHIBITS THE VASCULAR RESPONSE TO CSD
34CGS 15943 attenuates vascular reactivity during
CSD
250 µm
250 µm
35RELATED PHENOMENA
- GLIAL CALCIUM WAVES
- SPREADING DEPRESSION
- SPREADING HYPER/OLIGEMIA OF MIGRAINE SEEN ON PET,
fMRI - CLINICAL MANIFESTATIONS OF MIGRAINE AURA
36NEURONAL ACTIVATION
GLIAL WAVES?
GLUTAMATE RELEASE
ATP RELEASE (?)
INCREASED K
SPREADING DEPRESSION
SPREADING HYPER/ OLIGEMIA
BRAINSTEM ACTIVATION
PEPTIDERELEASE
VESTIBULAR SYMPTOMS
PAIN
AURA
Nausea
37CONCLUSIONS
- MICROSCOPIC IMAGING REVEALS MULTIPLE POTENTIAL
CELLULAR COMPONENTS OF MIGRAINE - GLIAL CELLS MAY PLAY AN IMPORTANT ROLE
- INDIVIDUAL MIGRAINE PHENOMENA MAY INVOLVE
DISTINCT CELLULAR SIGNALING PATHWAYS WITH
DISTINCT THRESHOLDS
38(No Transcript)
39ACKNOWLEDGEMENTS
- CHARLES LAB
- Marni Harris-White
- Luis Beltran-Parrazal
- K.C. Brennan
- UCLA LABORATORY OF NEUROIMAGING
- Arthur Toga
- Michael Guiou
- MICHAEL SANDERSON - University of Massachussetts