Blood-Brain Barrier (BBB)
Definition
The blood-brain barrier (BBB) is a highly selective semipermeable border of endothelial cells connected by tight junctions that separates the circulating blood from the brain extracellular fluid and central nervous system. The BBB restricts the passage of most molecules larger than approximately 400-500 Daltons, including the majority of peptides, while allowing the transport of essential nutrients, gases, and select small lipophilic molecules. Strategies to deliver peptides across the BBB include intranasal administration (exploiting the olfactory/trigeminal pathway), receptor-mediated transcytosis, and structural modifications to enhance lipophilicity or exploit endogenous transport systems.
Related Terms
Related Compounds
Semax
An in-depth review of Semax, a synthetic ACTH(4-10) analog, examining its nootropic properties, BDNF and NGF upregulation, neuroprotective mechanisms, and applications in cognitive enhancement research.
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An in-depth review of Selank, a synthetic tuftsin analog heptapeptide, covering its anxiolytic mechanisms, cognitive enhancement potential, GABA modulation, immunomodulatory properties, and key published research findings.
Read monographDihexa
An in-depth review of Dihexa, a potent angiotensin IV analog and HGF/c-Met signaling activator, examining its role in synaptogenesis, cognitive enhancement, neuroplasticity, and dementia-related research.
Read monographRelated Studies
Effects of an Angiotensin IV Analog on 3-Nitropropionic Acid-induced Huntington's Disease-Like Symptoms in Rats
Wells RG, Yamamoto BK, Wright JW, et al. · Journal of Huntington's Disease (2024)
Antidepressant-like and antistress effects of Semax in rats subjected to chronic unpredictable stress
Inozemtseva LS, Karpenko EA, Dolotov OV, et al. · European Journal of Pharmacology (2024)
Procognitive and synaptogenic effects of angiotensin IV-derived peptides are dependent on activation of the hepatocyte growth factor/c-met system
Benoist CC, Kawas LH, Zhu M, et al. · Journal of Pharmacology and Experimental Therapeutics (2014)
A novel angiotensin IV/AT4 receptor ligand, Nle1-AngIV (dihexa), is a potent procognitive agent that augments hepatocyte growth factor (HGF)/Met signaling
McCoy AT, Benoist CC, Wright JW, et al. · Journal of Pharmacology and Experimental Therapeutics (2013)