Stroke results from the transitory or permanent reduction of cerebral blood flow. It can be
classified as hemorrhagic or ischemic. Ischemic stroke is responsible for around 87% of all
cases. This acute neural disorder is the second cause of mortality and disability around the
world and the main cause of death in Brazil. Since ischemic stroke in patients usually
results from a thrombotic or embolic occlusion of the middle cerebral artery (MCA),
experimental models of ischemia have been developed to mimic human stroke. There are
no neuroprotective drugs available for human stroke. It follows that research on
development of alternative neuroprotective drugs are of important clinical relevance. In
this study, we investigated the effects of betacaryophyllene, the main sesquiterpene present
in about 40% of the copaiba oil-resin composition, on microglial activation, astrocytic
reactivity and neuronal preservation following experimental MCAO in adult rats. Animals
were submitted to experimental stroke by microinjections of endothelin-1 (ET-1) and
treated (i.p) with betacaryophillene (N=4) or vehicle control (N=4) and perfused at 3 days
or 7 days post-MCAO. Gross histopathology was performed using cresyl violet staining.
Immunohistochemistry was used to assess neuronal loss (anti-NeuN), microglial activation
(anti-ED1) and astrocytosis (anti-GFAP). Numbers of NeuN+ and GFAP+ cells were
quantified in the ischemic striatum. Betacaryophyllene treatment reduced microglial
activation, increased neuronal preservation and decreased astrocytic reactivity at 7 days
post-MCAO. These results suggest that betacaryophylene modulates neuroinflammation
and is neuroprotective following experimental striatal. Considering that betacaryophyllene
is a natural dietetic extract already used in non-neural human diseases with antiinflammatory,
anti-microbial and anti-carcinogenic properties, its use as a neuroprotective
agent is a promising future therapy for human stroke.
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