Inhibitory effect of Nifedipine on aldose reductase delays cataract progression.
Level 5 - mechanism / opinion, no new human data
Preclinical in vitro and animal (rodent) experimental study
PubMed 37395794 · doi:10.1007/s00210-023-02588-1
What was done
Researchers evaluated the inhibitory activity of the calcium channel blocker nifedipine against aldose reductase (ALR2/hAR) using molecular modeling, in vitro enzyme kinetics, isothermal titration calorimetry (ITC), and fluorescence quenching. In vivo efficacy was tested in a streptozotocin (STZ)-induced diabetic rat model to assess cataract progression, antioxidant status (SOD, CAT, GPX, GSH, TBARS, protein carbonyls), lens calcium levels, and α-crystallin chaperone activity.
What was found
Nifedipine inhibited recombinant human aldose reductase with an IC50 of 2.5 µM and a dissociation constant (Kd) of 2.91 ± 1.87 × 10⁻⁴ M. In STZ-induced diabetic rats, nifedipine delayed the onset and progression of cataracts, preserved antioxidant enzyme activity, reduced lipid peroxidation (TBARS) and protein carbonylation, decreased lens calcium accumulation, and maintained α-crystallin chaperone activity.
Why it matters
Aldose reductase inhibition is a key target for preventing diabetic cataracts, but many candidate inhibitors have lacked specificity. These findings demonstrate that nifedipine repurposing may provide both ALR2 inhibition and antioxidant lens protection in diabetic models.
Limits
The study is restricted to cell-free assays and rodent models, with exact animal cohort numbers, dosing regimens, and statistical effect sizes omitted from the abstract. Whether these biochemical concentrations and lens effects translate safely and effectively to humans remains unproven.
Cited by
- supports In the lens of the eye, aldose reductase converts glucose to sorbitol, which acts as an osmolyte, causing lens fibers to swell and burst to form cataracts.