Protection of DNA and membranes from gamma-radiation induced damages by Centella asiatica.
OBJECTIVE
The objective of the present study was to examine the ability of Centella asiatica extract to offer protection to DNA and membranes against the deleterious effects of ionizing radiation exposure.


METHODS
Protection of DNA under in-vitro conditions of irradiation was estimated using plasmid relaxation assay. For in-vivo studies the extract was administered orally to mice exposed to whole-body gamma-radiation. The ability of the extract to offer protection against whole-body gamma-radiation exposure was analysed by performing an alkaline comet assay on mouse bone marrow cells. The extent of lipid peroxidation was estimated using the TBARS (thio-barbituric acid reacting substances) method, in order to monitor membrane damage. Radiation-induced mortality of the animals following a lethal dose of gamma-radiation was also examined.


RESULTS
Centella asiatica extract significantly reduced radiation-induced damage to DNA. The extent of radiation-induced mortality and lipid peroxidation was also found to be considerably reduced in animals administered with the extract.


CONCLUSIONS
Centella asiatica rendered radioprotection to DNA and membranes against radiation exposure, both in vitro and in vivo. We have earlier reported that administration of the extract can prevent a radiation-induced decline in antioxidant enzyme levels. This suggests that radioprotection by Centella asiatica extract could be mediated by mechanisms that act in a synergistic manner, especially involving antioxidant activity.
Joy
Jisha
J
Amala Cancer Research Centre, Kerala, India.
Nair
Cherupally Krishnan Krishnan
CK
D000818:Animals; D002462:Cell Membrane / Q000187:drug effects* / Q000378:metabolism / Q000528:radiation effects; D028041:Centella; D020552:Comet Assay; D004247:DNA / Q000187:drug effects / Q000528:radiation effects; D004249:DNA Damage; D004305:Dose-Response Relationship, Drug; D004307:Dose-Response Relationship, Radiation; D005720:Gamma Rays; D066298:In Vitro Techniques; D015227:Lipid Peroxidation / Q000187:drug effects / Q000528:radiation effects; D008297:Male; D051379:Mice; D018384:Oxidative Stress / Q000187:drug effects; D008517:Phytotherapy; D010936:Plant Extracts / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use; D011833:Radiation Injuries, Experimental / Q000401:mortality / Q000517:prevention & control*; D011837:Radiation-Protective Agents / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism; D014315:Triterpenes; D014916:Whole-Body Irradiation
C526146:Centella asiatica extract; D010936:Plant Extracts; D011837:Radiation-Protective Agents; D017392:Thiobarbituric Acid Reactive Substances; D014315:Triterpenes; D004247:DNA