Platelet Purinergic receptors in CNS:
There are numerous types of purinergic receptors that constitute the so
called purinergic system. They include the those in platelets that are
P2Y1, P2Y12 and P2X1. They are in the initial stage of research. Some
preclinical studies have shown effects in the early stages which are
promising to carry them forward. P2Y12 receptors levels are associated
with Multiple sclerosis. They were found to be lower in patients with MS
near the demyelination areas [8]. This shows that there is some
association between multiple sclerosis and its progression, but the
nature or type of association has to be established and explained.
Another study that involved Experimental Autoimmune Encephalomyelitis
mouse models showed that the P2Y12 knockout mice developed severe EAE
when compared to others [9]. This was proposed to be due to higher
IL-23 release. Another reason given was due to imbalance between
cytokines and Th cells (T-helper cells). These are the roles until now
discovered for autoimmune and inflammatory diseases. Their role in
neurodegenerative diseases is also well studied in preclinical models.
The studies done for Parkinson’s disease shows that P2X1 receptor is
involved. Antagonism of this receptor leads to reduced α-synuclein in
the brain of tested mouse models [10]. This effect was brought about
in a dose dependent manner mediated by ATP inhibition. Other than these
preclinical studies the purinergic receptors of other subtypes that is
those that are non-platelet purinergic receptors have immense roles that
have been studied in CNS disorders and these might influence the
existing therapeutics in future including rare and fatal diseases. But
the practicality of these can be established with only sustained
research in future.
Figure 1:
A)Chronic inflammation B) Acute inflammation