Effects of puerarin on inducible nitric oxide synthase in lens during diabetic cataract in rats / 中国病理生理杂志

ABSTRACT

AIM: To study the changes of iNOS mRNA ,protein and the production of nitric oxide(NO) as well as whether puerarin regulates the expression of iNOS mRNA during the formation of diabetic rat cataract. METHODS: One hundred and eight Sprague-Dawley(SD) rats were randomly divided into three groups, thirty-six rats were taken as control group, seventy two rats were injected peritoneally with streptozotocin(STZ,45mg/kg) to establish animal model of diabetic cataract, and then divided into STZ (36) and puerarin(36) treatment groups. Morphologic changes of lens were observered with slit lamp and light microscope; Samples were taken at 20th, 40th, 60th day and the changes in iNOS mRNA and protein expression of lens epithelium cells(LEC)as well as production of NO and NOS activity were determined with reverse transcription -polymerase chain reaction(RT-PCR), western blot, and biochemical method ,respectively. RESULTS: Morphologyic changes of LEC, up-regulation of iNOS mRNA and iNOS protein as well as increase in NO production and NOS activity in the LEC were observered during the formation of rat diabetic cataract. Compared with TZ group, puerarin treatment group showed distinctly down-regulation of iNOS mRNA and iNOS protein and decrease in NO production and NOS activity as well as attenuation of morphologic changes. CONCLUSIONS: There are morphologic changes of LEC and up-regulation of iNOS mRNA and as well as increase in NO production and NOS activity in the LEC during the formation of diabetic rat cataract , and treatment with puerarin can reverse the above changes.