Engineered Coiled-Coil Protein for Delivery of Inverse Agonist for Osteoarthritis

Abstract

Osteoarthritis (OA) results from degenerative and abnormal function of joints, with localized biochemistry playing a critical role in its onset and progression. As high levels of all- trans retinoic acid (ATRA) in synovial fluid have been identified as a contributive factor to OA, the synthesis of de novo antagonists for retinoic acid receptors (RARs) has been exploited to interrupt the mechanism of ATRA action. BMS493, a pan-RAR inverse agonist, has been reported as an effective inhibitor of ATRA signaling pathway; however, it is unstable and rapidly degrades under physiological conditions. We employed an engineered cartilage oligomeric matrix protein coiled-coil (C) protein for the encapsulation, protection, and delivery of BMS493. In this study, we determine the binding affinity of C to BMS493 and the stimulator, ATRA, via competitive binding assay, in which ATRA exhibits approximately 5-fold superior association with C than BMS493. Interrogation of the structure of C indicates that ATRA causes about 10% loss in helicity, while BMS493 did not impact the structure. Furthermore, C self-assembles into nanofibers when bound to BMS493 or ATRA as expected, displaying 11-15 nm in diameter. Treatment of human articular chondrocytes in vitro reveals that C·BMS493 demonstrates a marked improvement in efficacy in reducing the mRNA levels of matrix metalloproteinase-13 (MMP-13), one of the main proteases responsible for the degradation of the extracellular cartilage matrix compared to BMS493 alone in the presence of ATRA, interleukin-1 beta (IL-1β), or IL-1 β together with ATRA. These results support the feasibility of utilizing coiled-coil proteins as drug delivery vehicles for compounds of relatively limited bioavailability for the potential treatment of OA.

Self-Assembled Protein- and Peptide-Based Nanomaterials

“…20−22 A serine variant of COMPcc, COMPcc s , or His 6 -C, has been shown to self-assemble into nanofibers in the range of 10−15 nm (Figure 4a, Table 1). 23,24 This ability to self-assemble into fibers renders COMPcc s an interesting candidate for further research. By using single alanine mutagenesis, Gunasekar et al have delineated the residues important for COMPcc s to form a coiled-coil fiber.…”

Attenuation of Hypertrophy in Human MSCs via Treatment with a Retinoic Acid Receptor Inverse Agonist

“…Thus, the topical application by intraarticular injection would be favorable. For the therapy of osteoarthritis, Yin et al developed a drug delivery system especially for BMS using an engineered cartilage oligomeric matrix protein coiled-coil protein to encapsulate and protect the hydrophobic and unstable BMS molecule [56].…”

Advances in intracellular delivery through supramolecular self-assembly of oligonucleotides and peptides

“…The remaining residues (the b, c, and f) are not the main driving forces for assembly but can be used to decorate the SAPs 115. Coiled coil-based SAPs have been developed to deliver small molecules 116,117, biomacromolecules 118, imaging agents 119, or other nanoparticles 119,120. Yin et al engineered a cartilage oligomeric matrix protein that forms the coiled-coil structure which enables encapsulation of a small molecule intended to prevent degeneration of joints (Figure 7B).…”

“…These nanofibers would be implanted for the treatment of osteoarthritis. Reproduced with permission from 117, Copyright 2018, American Chemical Society.…”