Propolis and Caffeic Acid Phenethyl Ester Attenuates Nitrosative Stress in Lens Tissue in Radiation-induced Cataracts in Rats

ABSTRACT

ABSTRACT Objective: Eye morbidity is widely observed in patients receiving total body irradiation prior to bone marrow transplantation or radiotherapy for ocular or head and neck cancers. Cataract blindness is the major cause of preventable blindness worldwide, especially in the developing countries. The aim of this study was to investigate whether propolis and caffeic acid phenethyl ester (CAPE) prevent radiation-induced cataractogenesis. Methods: Fifty-four Sprague-Dawley rats were randomly divided into six groups. Group 1 (irradiation (IR) + propolis) received total cranium irradiation and propolis was given orally through an orogastric tube daily. Group 2 (IR+CAPE) received total cranium irradiation plus CAPE intraperitoneally every day. Group 3 (IR) received 5 Gy of gamma irradiation as a single dose to total cranium plus 1 ml saline daily. Group 4 received daily plain saline. Group 5 received daily plain dimethyl sulfoxide. Group 6 (normal control group) did not receive anything. Results: At the end of the 10-day time period, cataracts developed in 80% of the rats in group 3 (IR group). After irradiation, cataract rate drop to 30% and 40% in groups treated with propolis and CAPE, respectively. Nitric oxide synthase activity, nitric oxide (NO•) and peroxynitrite (ONOO-) levels were significantly higher in group 3 compared to all other groups. Conclusion: The results suggest that propolis and CAPE have free radical scavenging activities in the irradiation-induced cataractogenesis, and reduced nitrosative stress markers. Prop-olis was found to be more effective in anticataractogenic effect than CAPE.