10 research outputs found
Modulation of glutathione and antioxidant enzymes by <i>Ocimum sanctum </i>and its role in protection against radiation injury
262-268Aqueous
extract (OE) of the leaves of Ocimum sanctum, the Indian holy basil, has
been found to protect mouse against radiation lethality and chromosome damage
and to possess significant antioxidant activity in vitro. Therefore a
study was conducted to see if OE protects against radiation induced lipid peroxidation
in liver and to determine the role, if any, of the inherent antioxidant system
in radioprotection by OE. Adult Swiss mice were injected intraperitoneally (ip)
with 10 mg/kg of OE for 5 consecutive days and exposed to 4.5 Gy of gamma
radiation 30 min after the last injection. Glutathione (GSH)
and the
antioxidant enzymes glutathione transferase (GST), reductase (GSRx), peroxidase
(GSPx) and superoxide dismutase (SOD), as well as lipid peroxide (LPx) activity
were estimated in the liver at 15min, 30min, 1, 2, 4 and 8 hr post-treatment. LPx
was also studied after treatment with a single dose of 50 mg/kg of OE with/without
irradiation. OE itself increased the GSH and enzymes significantly above normal
levels whereas radiation significantly reduced all the values. The maximum decline
was at 30-60 min for GSH and related enzymes and at 2 hr for SOD. Pretreatment
with the extract checked the radiation induced depletion of GSH and all the
enzymes and maintained their levels within or above the control range. Radiation
significantly increased the lipid peroxidation rate, reaching a maximum value
at 2 hr after exposure (-3.5 times that of control). OE pretreatment
significantly (P<0.0001) reduced the lipid peroxidation and
accelerated recovery to normal levels. The results indicate that Ocimum extract
protects against radiation induced lipid peroxidation and that GSH and the antioxidant
enzymes appear to have an important role in the protection