TAT-mediated peroxiredoxin 5 and 6 protein transduction protects against high-glucose-induced cytotoxicity in retinal pericytes

• Published in: Life sciences (1973) 2009-06, Vol.84 (23), p.857-864
• Main Authors: Kubo, Eri, Singh, Dhirendra. P., Fatma, Nigar, Akagi, Yoshio
• Format: Article
• Language: English
• Subjects: Animals; Apoptosis - genetics; Cells, Cultured; Diabetes; Female; Glucose - toxicity; HIV-1 - genetics; HIV-1 - physiology; Human immunodeficiency virus 1; Humans; Oxidative stress; Pericyte; Pericytes - metabolism; Pericytes - pathology; Peroxiredoxin; Peroxiredoxin VI - administration & dosage; Peroxiredoxin VI - biosynthesis; Peroxiredoxin VI - genetics; Peroxiredoxins - administration & dosage; Peroxiredoxins - biosynthesis; Peroxiredoxins - genetics; Rats; Rats, Sprague-Dawley; Recombinant Proteins - administration & dosage; Retina - metabolism; Retina - pathology; Retinopathy; Swine; tat Gene Products, Human Immunodeficiency Virus - genetics; tat Gene Products, Human Immunodeficiency Virus - physiology; Transduction, Genetic
• ISSN: 0024-3205; 1879-0631
• DOI: 10.1016/j.lfs.2009.03.019

Hyperglycemia-induced oxidative stress is implicated in pericyte apoptosis seen in diabetic retinopathy. The six mammalian Peroxiredoxins (PRDXs) comprise a novel family of antioxidative proteins that negatively regulate oxidative stress-induced apoptosis by controlling reactive oxygen species (ROS) levels. Sprague–Dawley rats were used to detect the retinal expressions of PRDXs1–6. Pig pericytes cultured in high-glucose medium were used to monitor the protective effect of PRDX5 and 6 against high-glucose-associated change. Recombinant PRDX5 and 6 proteins were linked to the Trans-Activating Transduction (TAT) domain from HIV-1 TAT protein for their efficient delivery into cells/tissues. We found higher expression of PRDX5 and 6 mRNAs and PRDX5 and 6 proteins in retina than the other Prdxs ( Prdx 1–4). Western blotting affirmed the intracellular presence of TAT-linked proteins and revealed the efficient transduction of TAT-HA-PRDX5 and 6 in these cells. Extrinsic supply of TAT-HA-PRDX5 and 6 proteins inhibited the oxidative stress-induced DNA damage after high-glucose exposure in pig pericytes. The cell survival and apoptosis assay revealed that extrinsic supply of TAT-HA-PRDX5 and 6 proteins was responsible for inhibiting hyperglycemia-induced pericyte apoptosis. Results suggest that delivery of PRDX5 and 6 might protect hyperglycemia-induced pericyte loss to inhibit oxidative stress.