Aldose reductase deficiency protects sugar-induced lens opacification in rats

Aramati B M Reddy, Ravinder Tammali, Rakesh Mishra, Shriram Srivastava, Satish Srivastava, Kota Ramana

Research output: Contribution to journalArticle

20 Scopus citations

Abstract

Aldose reductase (AKR1B1), which catalyzes the reduction of glucose to sorbitol and lipid aldehydes to lipid alcohols, has been shown to be involved in secondary diabetic complications including cataractogenesis. Rats have high levels of AKR1B1 in lenses and readily develop diabetic cataracts, whereas mice have very low levels of AKR1B1 in their lenses and are not susceptible to hyperglycemic cataracts. Studies with transgenic mice that over-express AKR1B1 indicate that it is the key protein for the development of diabetic complications including diabetic cataract. However, no such studies were performed in genetically altered AKR1B1 rats. Hence, we developed siRNA-based AKR1B1 knockdown rats (ARKO) using the AKR1B1-siRNA-pSuper vector construct. Genotyping analysis suggested that more than 90% of AKR1B1 was knocked down in the littermates. Interestingly, all the male animals were born dead and only 3 female rats survived. Furthermore, all 3 female animals were not able to give birth to F1 generation. Hence, we could not establish an AKR1B1 rat knockdown colony. However, we examined the effect of AKR1B1 knockdown on sugar-induced lens opacification in ex vivo. Our results indicate that rat lenses obtained from AKR1B1 knockdown rats were resistant to high glucose-induced lens opacification as compared to wild-type (WT) rat lenses. Biochemical analysis of lens homogenates showed that the AKR1B1 activity and sorbitol levels were significantly lower in sugar-treated AKR1B1 knockdown rat lenses as compared to WT rat lenses treated with 50 mM glucose. Our results thus confirmed the significance of AKR1B1 in the mediation of sugar-induced lens opacification and indicate the use of AKR1B1 inhibitors in the prevention of cataractogenesis.

Original languageEnglish (US)
Pages (from-to)346-350
Number of pages5
JournalChemico-Biological Interactions
Volume191
Issue number1-3
DOIs
StatePublished - May 30 2011

    Fingerprint

Keywords

  • Aldose reductase
  • Cataract
  • Lens opacification
  • Oxidative stress
  • SiRNA knock-down rats

ASJC Scopus subject areas

  • Toxicology

Cite this