Engineered Sumoylation-Deficient Prdx6 Mutant Protein-Loaded Nanoparticles Provide Increased Cellular Defense and Prevent Lens Opacity

Bhavana Chhunchha; Eri Kubo; Uday B Kompella; Dhirendra P Singh

doi:10.3390/antiox10081245

Engineered Sumoylation-Deficient Prdx6 Mutant Protein-Loaded Nanoparticles Provide Increased Cellular Defense and Prevent Lens Opacity

Antioxidants (Basel). 2021 Aug 4;10(8):1245. doi: 10.3390/antiox10081245.

Authors

Bhavana Chhunchha¹, Eri Kubo², Uday B Kompella³, Dhirendra P Singh¹

Affiliations

¹ Ophthalmology and Visual Sciences, University of Nebraska Medical Center, Omaha, NE 68198, USA.
² Department of Ophthalmology, Kanazawa Medical University, Kanazawa 9200265, Ishikawa, Japan.
³ Departments of Pharmaceutical Sciences, Ophthalmology, and Bioengineering, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA.

Abstract

Aberrant Sumoylation-mediated protein dysfunction is involved in a variety of oxidative and aging pathologies. We previously reported that Sumoylation-deficient Prdx6K^{(lysine)122/142R(Arginine)} linked to the TAT-transduction domain gained stability and protective efficacy. In the present study, we formulated wild-type TAT-HA-Prdx6^WT and Sumoylation-deficient Prdx6-loaded poly-lactic-co-glycolic acid (PLGA) nanoparticles (NPs) to further enhance stability, protective activities, and sustained delivery. We found that in vitro and subconjuctival delivery of Sumoylation-deficient Prdx6-NPs provided a greater protection of lens epithelial cells (LECs) derived from human and Prdx6^-/--deficient mouse lenses against oxidative stress, and it also delayed the lens opacity in Shumiya cataract rats (SCRs) than TAT-HA-Prdx6^WT-NPs. The encapsulation efficiencies of TAT-HA-Prdx6-NPs were ≈56%-62%. Dynamic light scattering (DLS) and atomic force microscopy (AFM) analyses showed that the NPs were spherical, with a size of 50-250 nm and a negative zeta potential (≈23 mV). TAT-HA-Prdx6 analog-NPs released bioactive TAT-HA-Prdx6 (6%-7%) within 24 h. Sumoylation-deficient TAT-HA-Prdx6-NPs provided 35% more protection by reducing the oxidative load of LECs exposed to H₂O₂ compared to TAT-HA-Prdx6^WT-NPs. A subconjuctival delivery of TAT-HA-Prdx6 analog-NPs demonstrated that released TAT-HA-Prdx6^K122/142R could reduce lens opacity by ≈60% in SCRs. Collectively, our results demonstrate for the first time that the subconjuctival delivery of Sumoylation-deficient Prdx6-NPs is efficiently cytoprotective and provide a proof of concept for potential use to delay cataract and oxidative-related pathobiology in general.

Keywords: antioxidants; nano-formulation; nanoparticles; oxidative stress; peroxiredoxin 6; protective mutation; sumoylation; transduction domain.

Abstract

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