0-TESTO COMPLETO.pdf - Fondazione Santa Lucia

Sezione III: Attività per progetti
U.O.4 – Laboratorio di Neurofisiologia
Diego Centonze
Specific contribution of the unit to the project
The classical divide between degenerative and inflammatory disorders of
the CNS is vanishing, as our understanding on the intimate nature of several
disease conditions is improving. Inflammatory processes play an important
role in the pathophysiology of primarily degenerative disorders such as HD
and ALS, and neurodegeneration complicates primarily inflammatory diseases
of the brain and spinal cord such as multiple sclerosis (MS). Microglia
is emerging as a fundamental player in the crosstalk between inflammation
and neurodegeneration, since it is activated by both processes and boost, in
turn, both neuroinflammation and neurodegeneration. An apparently unique
opportunity to interfere at once with neurodegeneration and neuroinflammation
processes originates from the modulation of the endocannabinoid system
(ECS). Accordingly, central neurons and immune cells possess the biochemical
machinery required for endocannabinoid synthesis, transport and degradation,
and respond to the stimulation of cannabinoid CB1 and CB2 receptors
by changing their physiological activity. In neurons, cannabinoid may regulate
both excitatory and inhibitory transmission through pre- and postsynaptic
mechanisms, while in immune cells and in microglia, the activation of
cannabinoid receptors significantly alters their metabolic activity and
responses during inflammation.
Based on these considerations, in the present research project we aim at
clarifying the role of microglia and of the ECS system in the pathophysiology
of experimental HD, ALS and MS. In particular, since changes of both excitatory
and inhibitory transmission represent early events triggering secondary
excitotoxicity and inflammatory neurodegeneration, we will measure synaptic
transmission in the three models of inflammatory neurodegeneration by
means of neurophysiological recordings in corticostriatal brain slices during
the modulation of the ECS. A peculiar susceptibility of the corticostriatal system
in HD, ALS and MS, in fact, has been convincingly documented. The role
of microglia in the possible changes of synaptic transmission induced by
these disorders will be investigated by direct incubation of corticostriatal
slices with quiescent and activated microglial cells, as well as with cytokines
produced by microglia.
Methods
The effects of pharmacological modulation of cannabinoid system will be
investigated in experimental HD, ALS and MS and in their respective controls.
In particular, we will perform in vitro whole-cell patch clamp electrophysiological
recordings in corticostriatal brain slices prepared from mouse
models of HD (R6/2 mutant mice; Jackson Laboratories, Bar Harbor, ME,
USA), ALS (B6SJL-TgN(SOD1-G93A)1Gur mice, Jackson Laboratories, Bar
750 2009