DRUG DELIVERY SYSTEMS THROUGH THE NASAL MUCOSA (REVIEW)
The most difficult aspect in the treatment of diseases of the central nervous system (CNS) is the targeted delivery of drugs to target tissues of the brain. some of the pharmacological groups used in the pathology of the central nervous system are able to overcome the blood-brain barrier (BBB).The science of pharmacology studies and develops new drugs every year, but potential routes of administration to bypass the BBB are still not fully understood. And one of these ways is intranasal delivery. The annual increase in scientific publications of this kind of articles suggests that the anatomical pathways connecting the nasal cavity with the brain help to increase the effectiveness of administered medicines.The exact mechanisms of medicine delivery during intranasal administration remain not fully understood.However, scientific evidence from recent decades suggests that drug delivery involves the perineural and perivascular spaces of the trigeminal and olfactory nerves. Purpose and objectives: to analyze the scientific literature on intranasal drug delivery routes, which will subsequently serve as the basis for the development of new mucoadhesive dosage forms for the treatment of brain pathology. Materials and methods of research. We conducted an analysis of scientific publications within the framework of our goals. For the review of the literature, articles were used in the search engines "ResearchGate" and "GoogleScholar", as well as those indexed in the databases PubMed, Scopus, Medline, Cyberleninka, E-library. Search filters contained the following criteria: intranasal routes of drug administration in CNS pathologies, mucoadhesive dosage forms, perivascular and perineural spaces, experimental studies with intranasal administration published in Russian and English over the past decade. Results. An analysis of all the studied literature data indicates that the intranasal route of drug administration has great potential for the non-invasive use of new dosage forms through direct routes connecting the nasal passages with the central nervous system. The positive characteristics of the intranasal route of administration will mainly allow patients to self-administer drugs, which will significantly reduce the side pharmacological effects of a systemic nature. In preclinical studies, there are results on the use of small molecule substances to stem cells in the treatment of diseases of the central nervous system. However, at the same time, questions about the ways and mechanisms of regulation of intranasal administration remain not fully understood. A more detailed study of the characteristics of the epithelium of the olfactory nerve and the mechanisms of transport of substances will make it possible to determine the range of pharmacological groups for better penetration into the central nervous system when administered intranasally. Particular attention is required to study the perivascular and perineural fluids that pass through the plates within the trigeminal nerve. If the extracellular fluid flows within the studied nerves in two directions, then this improves the physiological and pharmacological consequences of the administered drugs. As a result of the data obtained, the understanding of the anatomical and physiological aspects of drug delivery through the nasal passages to the CNS is improving, which will ultimately lead to significant progress in the treatment of CNS diseases. Ultimately, all this will increase the effectiveness of treatment methods for this route of administration of new mucoadhesive dosage forms.