Antioxidant, anticlastogenic and radioprotective effect of Coleus aromaticus on Chinese hamster fibroblast cells (V79) exposed to gamma radiation.
Coleus aromaticus (Benth, Family: Laminaceae), Indian Oregano native to India and Mediterranean, is well known for its medicinal properties. A preliminary study was undertaken to elucidate in vitro free radical scavenging potential and inhibition of lipid peroxidation by C.aromaticus hydroalcoholic extract (CAE). Anti-clastogenic and radioprotective potential of CAE were studied using micronucleus assay after irradiating Chinese hamster fibroblast (V79) cells. CAE at 10, 20, 40, 60, 80, 100 and 120 mug/ml resulted in a dose-dependent increase in radical scavenging ability against various free radicals viz., 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), superoxide anion (O(2)(*-)), hydroxyl (OH(*)) and nitric oxide (NO(*)) generated in vitro. A maximum scavenging potential was noticed at 100 mug/ml and a saturation point was reached thereafter with the increasing doses of CAE. The free radical scavenging potential of the extract was in the order of DPPH > ABTS > Superoxide > Hydroxyl > Nitric oxide. CAE also exhibited a moderate inhibition of lipid peroxidation in vitro, with a maximum inhibition at 60 mug/ml (33%), attaining saturation at higher doses. The extract also rendered protection against radiation induced DNA damage, as evidenced by the significant (P < 0.05) decrease in the percentage of radiation-induced micronucleated cells (MN) and frequency of micronuclei (total). A maximum anticlastogneic effect/ radioprotection was noticed at a very low concentration i.e., 5 mug/ml of CAE, treated 1 h prior to 2 Gy of gamma radiation. A significant (P < 0.0001) anticlastogenic/radioprotective effect was also observed when the cells were treated with an optimum dose of CAE (5 mug/ml) 1 h prior to 0.5, 1, 2 and 4 Gy of gamma radiation compared with the respective radiation control groups. Overall, our results established an efficient antioxidant, anticlastogenic and radioprotective potential of CAE, which may be of great pharmacological importance.
Rao
B S Satish
BS
Department of Radiobiology, Life Sciences Center, Manipal 576104, Karnataka, India. raokmc@yahoo.com
Shanbhoge
R
R
Upadhya
D
D
Jagetia
G C
GC
Adiga
S K
SK
Kumar
P
P
Guruprasad
K
K
Gayathri
P
P
D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D001713:Biphenyl Compounds; D031330:Coleus / Q000378:metabolism*; D006224:Cricetinae; D004305:Dose-Response Relationship, Drug; D005347:Fibroblasts / Q000378:metabolism; D005720:Gamma Rays; D006834:Hydrazines; D015227:Lipid Peroxidation; D015162:Micronucleus Tests / Q000379:methods; D009153:Mutagens; D009569:Nitric Oxide / Q000737:chemistry; D008517:Phytotherapy; D010851:Picrates; D010936:Plant Extracts / Q000627:therapeutic use; D011837:Radiation-Protective Agents / Q000627:therapeutic use
D000975:Antioxidants; D001713:Biphenyl Compounds; D006834:Hydrazines; D009153:Mutagens; D010851:Picrates; D010936:Plant Extracts; D011837:Radiation-Protective Agents; D009569:Nitric Oxide; C004931:1,1-diphenyl-2-picrylhydrazyl