Strategic Mutations in Designer Native Peptides Combat NLRP3 Inflammasome Activation in Neurodegenerative Disorders

Nucleotide-binding oligomerization domain (NOD)-, leucine-rich repeat (LRR)-, and pyrin domain (PYD)-containing protein 3 (NLRP3) form an inflammasome by assembling with apoptosis-associated speck-like protein containing a CARD (ASC) and procaspase-1 that plays a pivotal role in various neurodegenerative diseases such as Alzheimer's and Parkinson diseases. We designed native peptides derived from the PYDs of NLRP3 and ASC based on their interfacial interaction to inhibit NLRP3 inflammasome formation. Screening revealed that NP3, derived from NLRP3, inhibits inflammasome activation. Furthermore, a strategic mutation (F → L) in native peptide NP3 results in MNP2 that selectively binds to PYD of ASC with nanomolar affinity, inhibiting NLRP3 inflammasome formation, interleukin-1β (IL-1β) release, and caspase-1 maturation. MNP2 also reduced potassium (K) and chloride (Cl) ion efflux, key signals in NLRP3 activation, and prevented mitochondrial damage and reactive oxygen species (ROS) production. MNP2 significantly reduced NLRP3 inflammasome formation in neurodegenerative conditions triggered by amyloid-β (Aβ), Tau, and α-Synuclein (α-Syn), suggesting a promising therapeutic strategy for NLRP3-related inflammatory diseases, including neurodegenerative disorders.