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Setting-up an In Vitro Model of Rat Blood-brain Barrier BBB: A Focus on BBB Impermeability and Receptor-mediated Transport
Published on: June 28, 2014
Medicinal chemistry strategies to breach the blood-brain barrier: structural design principles for brain-targeted
Harikesh Kumar Gupta1, Jatin Jangra1, Vishwakarma Krishna Ramesh1
1Department of Pharmaceutical Engineering and Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi, Uttar Pradesh 221005, India.
Abstract:
The blood-brain barrier (BBB) remains a critical limitation in central nervous system (CNS) drug development, restricting brain exposure to most therapeutics. Despite advances in macromolecular delivery, small molecules continue to predominate, necessitating the rational optimization of BBB permeability. This review integrates recent medicinal chemistry strategies focused on fine-tuning key physicochemical parameters, including lipophilicity, pKa, molecular weight, hydrogen bond donors, rotatable bonds and topological polar surface area, which govern passive diffusion and brain penetration. Structural modifications such as fluorination, bioisosteric replacement, intramolecular hydrogen bond masking and prodrug approaches are discussed alongside strategies to mitigate efflux and exploit carrier-mediated transport. The integration of in silico tools and experimental models provides a cohesive framework for designing next-generation CNS therapeutics with optimized permeability and efficacy profiles.
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