Recent investigations have shown that
phytochemical antioxidants can scavenge
free radicals and prevent various diseases.
Cataract is the leading cause of
blindness and is associated with oxidative damage of the lens.
Selenite-induced
cataract in rat pups is an excellent mimic of oxidative stress-induced
cataract.
Selenite cataract is associated with oxidative stress, loss of
calcium homeostasis,
calpain activation and
protein insolubilization in the lens. Our present study focuses on the isolation of
flavonoids from Vitex negundo and to assess its efficacy in preventing these changes in the lens of
selenite-induced
cataract models. Eight-day-old Sprague-Dawley rat pups were used for the study and divided into four groups: Control (G I),
Sodium selenite-induced (G II),
Sodium selenite+quercetin treated (G III),
Sodium selenite+flavonoids from Vitex negundo (FVN) (G IV).
Cataract was induced by a single
subcutaneous injection of
Sodium selenite (4 mg/Kg
body weight) on the 10th day. Treatment groups received
quercetin (1.0mg/Kg
body weight) and FVN (1.0mg/Kg
body weight) intraperitoneally from 8th to 15th day.
Cataract was visualized from the 16th day. Morphological examination of the rat
lenses revealed no opacification in G I and mild opacification in G III and G IV (stage 1) whereas dense opacification in G II (stage 4-6). The activities of
superoxide dismutase (SOD),
catalase, Ca(2+)
ATPase, concentration of
reduced glutathione (GSH) and
protein sulfhydryl content were significantly increased in G III and G IV compared to G II, while decreased activities of calpains, lower concentration of
calcium and
thiobarbituric acid reactive substances (
TBARS) were observed in G III and IV as compared to G II. Lens
protein profile of water soluble
proteins showed normal levels of expression in treated groups compared to that of
selenite-induced rats. These results indicate good
antioxidant and therapeutic potential of FVN in modulating biochemical parameters against
selenite-induced
cataract, which have been reported in this paper for the first time.