Impact of Peripheral Inflammation on Blood–Brain Barrier Dysfunction and Its Role in Neurodegenerative Diseases

The blood-brain barrier (BBB) is essential for maintaining brain homeostasis by regulating molecular exchange between the systemic circulation and the central nervous system. However, its dysfunction, often driven by peripheral inflammatory processes, has been increasingly linked to the development and progression of neurodegenerative diseases such as Alzheimer's and Parkinson's. Emerging evidence suggests that the gut-brain axis plays a key role in BBB integrity, with intestinal dysbiosis and chronic inflammation contributing to barrier disruption through immune and metabolic pathways. Furthermore, the selective vulnerability of specific brain regions to BBB dysfunction appears to be influenced by regional…