| First Author | Molnar KS | Year | 2019 |
| Journal | Invest Ophthalmol Vis Sci | Volume | 60 |
| Issue | 10 | Pages | 3320-3331 |
| PubMed ID | 31369034 | Mgi Jnum | J:279765 |
| Mgi Id | MGI:6343429 | Doi | 10.1167/iovs.18-25647 |
| Citation | Molnar KS, et al. (2019) Mechanism of Action of VP1-001 in cryAB(R120G)-Associated and Age-Related Cataracts. Invest Ophthalmol Vis Sci 60(10):3320-3331 |
| abstractText | Purpose: We previously identified an oxysterol, VP1-001 (also known as compound 29), that partially restores the transparency of lenses with cataracts. To understand the mechanism of VP1-001, we tested the ability of its enantiomer, ent-VP1-001, to bind and stabilize alphaB-crystallin (cryAB) in vitro and to produce a similar therapeutic effect in cryAB(R120G) mutant and aged wild-type mice with cataracts. VP1-001 and ent-VP1-001 have identical physicochemical properties. These experiments are designed to critically evaluate whether stereoselective binding to cryAB is required for activity. Methods: We compared the binding of VP1-001 and ent-VP1-001 to cryAB using in silico docking, differential scanning fluorimetry (DSF), and microscale thermophoresis (MST). Compounds were delivered by six topical administrations to mouse eyes over 2 weeks, and the effects on cataracts and lens refractive measures in vivo were examined. Additionally, lens epithelial and fiber cell morphologies were assessed via transmission electron microscopy. Results: Docking studies suggested greater binding of VP1-001 into a deep groove in the cryAB dimer compared with ent-VP1-001. Consistent with this prediction, DSF and MST experiments showed that VP1-001 bound cryAB, whereas ent-VP1-001 did not. Accordingly, topical treatment of lenses with ent-VP1-001 had no effect, whereas VP1-001 produced a statistically significant improvement in lens clarity and favorable changes in lens morphology. Conclusions: The ability of VP1-001 to bind native cryAB dimers is important for its ability to reverse lens opacity in mouse models of cataracts. |
