Nanoparticles displaying a brain-targeting peptide (KS-487) and loaded with a VIP receptor-blocking peptide (KS-133) successfully crossed the blood-brain barrier and improved cognitive dysfunction in schizophrenia model mice.
First multipeptide brain therapyFirst study to demonstrate therapeutic efficacy of a multifunctionalized nanoparticle using two peptides to cross the blood-brain barrier and treat schizophrenia
What the researchers found
KS-487-displaying nanoparticles encapsulating KS-133 successfully crossed the blood-brain barrier via subcutaneous injection. Pharmacokinetic analysis confirmed time-dependent transport of KS-133 into the brain. When administered to schizophrenia model mice, the nanoparticles significantly improved cognitive dysfunction. This is the first demonstration of a multipeptide nanoparticle achieving therapeutic efficacy by inhibiting VIPR2 in the brain.
Why it matters
Getting drugs into the brain is one of medicine's biggest challenges. This study shows that peptide-functionalized nanoparticles can solve two problems at once: crossing the blood-brain barrier (using KS-487) and delivering a therapeutic peptide (KS-133) to block a schizophrenia-linked receptor. This dual-peptide approach could be applied to other brain diseases.
The numbers in context
Two cyclic peptides: KS-133 (VIPR2 selective antagonist) and KS-487 (LRP1 cluster IV binder).
How the study worked
Nanoparticle preparation with KS-133 encapsulated and KS-487 displayed on the surface. Click chemistry conjugation of KS-487 with ICG for brain imaging. Subcutaneous and intravenous administration in mice. Fluorescence imaging confirmed brain accumulation. Pharmacokinetic analysis of brain transport. Cognitive testing in schizophrenia mouse models.
Who was studied
Preclinical drug delivery system development and testing
What this study cannot tell us
Mouse study only — blood-brain barrier permeability and drug efficacy may differ in humans. Schizophrenia mouse models have limited translational value. Long-term safety of repeated dosing unknown. Only cognitive dysfunction was assessed; other schizophrenia symptoms not tested.
How to read the evidence
Rated preliminary: proof-of-concept mouse study. Novel technology but unvalidated in larger animals or humans.
When this study was published
Published in 2024. Represents cutting-edge peptide nanotechnology for brain drug delivery.
The bigger picture
This represents a convergence of two peptide technologies — cell-penetrating/targeting peptides and therapeutic peptides — into a single delivery system. If this approach works in humans, it could open new treatment avenues for schizophrenia and other neuropsychiatric disorders.
Questions still open
- Could this dual-peptide nanoparticle approach treat other brain diseases beyond schizophrenia?
- What is the long-term safety profile of repeated subcutaneous nanoparticle injections?
- How does the brain concentration of KS-133 via nanoparticles compare to direct injection?
Common questions
Can peptides cross the blood-brain barrier?
Could peptide nanoparticles treat schizophrenia?
Read the original research
Cyclic Peptides KS-133 and KS-487 Multifunctionalized Nanoparticles Enable Efficient Brain Targeting for Treating Schizophrenia.
JACS Au, 4(8), 2811-2817
Citation
Sakamoto, Kotaro; Iwata, Seigo; Jin, Zihao; Chen, Lu; Miyaoka, Tatsunori; Yamada, Mei; Katahira, Kaiga; Yokoyama, Rei; Ono, Ami; Asano, Satoshi; Tanimoto, Kotaro; Ishimura, Rika; Nakagawa, Shinsaku; Hirokawa, Takatsugu; Ago, Yukio; Miyako, Eijiro. (2024). Cyclic Peptides KS-133 and KS-487 Multifunctionalized Nanoparticles Enable Efficient Brain Targeting for Treating Schizophrenia.. JACS Au, 4(8), 2811-2817. https://doi.org/10.1021/jacsau.4c00311