Regulation of Cataractogenesis by Hydrogen Sulfide-NSAID Hybrid Compounds in Cultured Bovine Lenses

Abstract

Purpose : Hydrogen sulfide (H₂S) releasing compounds and NSAIDs can mitigate cataractogenesis in vitro and in vivo (Zhang et al., Mol Vis, 14:862, 2008; Harding JJ et al., Acta Ophthalmol, 67:518, 1989). However, the role of NSAID-H₂S-releasing hybrid compounds on cataractogenesis has not been elucidated. In the present study, we compared the pharmacological effects of ATB343 (indomethacin & H₂S donor) and ATB337 (diclofenac & H₂S donor) on cataractogenesis in cultured bovine lenses and on lenticular antioxidants concentrations.

Methods : Freshly isolated bovine lenses were cultured in a DMEM buffer solution as follows: Group I: Control (DMEM); Group II: H₂O₂ (10 mM); Groups III-V: ATB343 (10^-7M); ATB337 (10^-7M); ascorbic acid (AA; 10^-3M) in presence and absence of H₂O₂ (10 mM). Lenses were incubated and were qualitatively and quantitatively assessed at 3, 6, 24, 48 and 72 h-time points by photographic captures and measurement of transmittance using a plate reader (Synergy H1 hybrid). Lenticular glutathione (GSH) and superoxide dismutase (SOD) were measured using Cayman Assay Kits.

Results : DMEM-cultured lenses exhibited a time-dependent decrease in transmittance (420nm) and a corresponding loss of lens optical clarity up to 72 h. Unlike ATB343 (10^-7M) and the endogenous antioxidant, AA (10 mM) which attenuated time-dependent lens degradation up to 24 h, ATB337 (10^-7M) decreased time-dependent transmittance, achieving an inhibition of 34.7 ± 1.12% (n=12; p<0.01) after 72 h. H₂O₂ (10 mM) reduced transmittance in a time-dependent manner, attaining an inhibition of 42.0 ± 1.0% (n=12; p<0.01) after 72 h. After 48 h, ATB343 (10^-7M) and ATB337 (10^-7M) enhanced time-dependent GSH depletion by 3.6%± 0.05% (n=3; p<0.05) and 2.7± 0.5% (n=3; p<0.05) and H₂O₂-induced GSH depletion by 12.3± 0.1% (n=3; p<0.01) and 8.7 ±0.4% (n=3; p<0.05), respectively. However, ATB343 enhanced SOD depletion by 35.3 ± 2.7% (n=3; p<0.001) but attenuated H₂O₂-induced SOD depletion by 56.6±3.1% (n=3; p<0.001) (t=48 h). Similarly, ATB337 enhanced time-dependent loss in SOD by 48.9 ± 4.4% (n=3; p<0.001) but reversed H₂O₂-induced SOD loss by 31.8 ± 4.9% (n=3; p<0.001) (t=48 h).

Conclusions : The NSAID-H₂S hybrid compounds, ATB343 and ATB337 can partially protect cultured bovine lenses from cataract formation, presumably via an effect on lenticular SOD concentrations.

This is a 2021 ARVO Annual Meeting abstract.