Peptides & Blood-Brain Barrier in Health & Disease | William Banks | Episode 300

Send us Fan MailBlood-brain barrier as a dynamic interface allowing selective passage of nutrients, peptides, and gut hormones.TOPICS DISCUSSED:Blood-Brain Barrier Structure: Capillary endothelial cells with tight junctions, absent fenestrae, and minimal vesicles create a selective interface; supported by astrocytes and pericytes.Crossing Mechanisms: Lipid-soluble small molecules diffuse passively; glucose, amino acids, and regulatory peptides use saturable transporters whose rates vary by need.Peptide Transport: Many peptides cross via lipid solubility or specific transporters; rate, not all-or-none presence, determines biological relevance; efflux systems remove some (e.g. certain enkephalins).Dynamic Regulation: Transporters for leptin and insulin are modulated by epinephrine, triglycerides, and brain demand; changes occur in aging and Alzheimer’s (reduced glucose uptake, impaired Aβ efflux).Circumventricular Organs: Leaky capillary regions allow rapid sampling of blood signals while tanycytes limit spread to surrounding brain tissue.Drug Delivery Challenges: Small lipid-soluble drugs, barrier disruption (e.g. focused ultrasound), and “Trojan-horse” strategies each have limitations; intranasal delivery shows rapid brain distribution.Peptides & Brain Effects: Gut peptides like GLP-1 analogs, insulin, and ghrelin influence cognition and memory; brain entry predicts central effects.GUEST: William Banks, MD is a physician-scientist and leading researcher on the blood-brain barrier. He has focused on humoral brain-body communication, peptide transport, and the barrier’s role in health and disease.RELATED CONTENT:M&M 298 | GLP-1s & Novel Peptides in Obesity, Diabetes & Metabolic Health | Katrin SvenssonSupport the showSupport my work:Good Chemistry: Personalized, science-based health consulting. Work with Dr. Nick Jikomes directly.Affiliate Partners: Visit this link to see my affiliate partners and get discounts codes for products & services to support health.For all the ways you can support my efforts.