THE ANTIOXIDANT EFFECT OF RHYNCHOSIA NULUBILIS EXTRACT IN THE XEROPHTHALMIA-INDUCED ANIMAL MODEL

Kyung-Yae Hyun*

ABSTRACT

The antioxidant effect of Rhynchosia nulubils extract (RNE) and iNOS protein expression of eyes and lachrymal glands were verified using the xerophthalmia-induced animal model. The animal groups are divided into the normal group (control), xerophthalmia-induced group (vehicle), high-concentration RNE administration group before inducing xerophthalmia that orally administered pre-high dose (250 mg/100g rat weight), low-concentration RNE administration group before inducing xerophthalmia that orally administered pre-low dose (65mg/100g rat weight), high-concentration RNE administration group after inducing xerophthalmia that orally administered post-high dose (250 mg/100g rat weight), low-concentration RNE administration group after inducing xerophthalmia that orally administered post-low dose (65mg/100g rat weight), and positive control group that orally administered omega-3 (85mg/100g rat weight). The nitric oxide antioxidant effect on the cornea specimen showed a statistically significant (p<0.05) decrease in all RNE administration groups compared to the vehicle group. For xanthine oxidase inhibitory activity, RNE was concentration dependent and showed superoxide radical scavenging activity, and showed at least a 55% scavenging effect compared to the positive in the 640 µg/mL concentration. For DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity, the positive control group showed nearly a 50% antioxidant effect in concentrations of 160 μg/mL or higher compared to ascorbic acid. The iNOS protein expression of eyes decreased statistically (p<0.05) in three groups (pre-low, post- high, post- low treat) compared to the vehicle group, and that of lachrymal glands decreased statistically (p<0.05) in pre-high and post-high treat group.

Keywords: Rhynchosia nulubils extract (RNE), Xerophthalmia, Antioxidant effect, iNOS.