However, only a small portion of the nasal mucosa in humans consists of olfactory epithelium, and researchers are focusing on improving it. drug delivery time through the predominant respiratory epithelium.
To facilitate this, a group of researchers developed a new drug to test the effectiveness of its uptake by the CNS. Journal of Controlled Release.
When studying the CNS uptake of this new PAS-CPP-GLP-2, they noted that its anti-depressant effects with intranasal (intranasal) administration remained the same as with intracerebroventricular (icv) administration of the same dose.
How do antidepressants cross the blood-brain barrier?
Therefore, they demonstrated a nose-to-brain transfer mechanism to explain why intranasally administered GLP-2 derivatives exerted the same drug effects as intracerebroventricularly administered GLP-2 derivatives.
The team’s findings have been documented. they performed icv. and administration of PAS-CPP-GLP-2 to mice. The amount of drug delivered to the whole brain was measured by enzyme-linked immunosorbent assay (ELISA).
Surprisingly, ELISA revealed that intranasally administered PAS-CPP-GLP-2 reached the brain in lower amounts than intracerebroventricularly administered PAS-CPP-GLP-2. However, both icv. and in administration showed efficacy at the same dose.
It is associated with icv. administration introduces drugs to the origin of the CSF (ventricle), causing them to diffuse into the CSF and through the brain.
On the other hand, nasally administered GLP-2 derivatives were rapidly taken up by the trigeminal nerve of the respiratory epithelium and reached an effective site while passing through neurons.
Effective nasal drug delivery of antidepressants
This suggests that the peptide is delivered to the site of action via icv. administration, there is a large amount in the brain, but very little because it remains in the perivascular space. On the other hand, unlike icv, PAS-CPP-GLP-2 is administered intranasally. administration can be transferred to the site of action without crossing the CSF or perivascular space.
The current data show the possibility of extending the use of this system from the treatment of depression to the delivery of drugs to patients with Alzheimer’s disease. It is therefore expected to be applied to neurodegenerative diseases, which have a high unmet medical need.