title: Phytochemical investigation and radical scavenging activities of Melia azedarach and its DNA protective effect in cultured lymphocytes.
abstract: BACKGROUND
  Melia azedarach Linn (Meliaceae) is an Ayurvedic medicinal plant which is native to India. It is traditionally used for the treatment of leprosy, inflammation, scrofula, anthelmintic, antilithic, diuretic, deobstruent and cardiac disorders.
  
  
  OBJECTIVE
  To evaluate the phytochemical constituents and antioxidant activities of the ethanol leaf extract of Melia azedarach (MA) and its protective effect against H2O2-induced cellular damage in cultured lymphocytes.
  
  
  METHODS
  The dose-dependent study of MA (20, 40, 60, 80, 100 µg/ml) was used to study in vitro radical scavenging assays. The effective dose of MA (60 µg/ml) was further used to study the H2O2-induced DNA damage (comet assay and DNA fragmentation assay) in cultured lymphocytes.
  
  
  RESULTS
  The ethanol extract of MA (20, 40, 60, 80, 100 µg/ml) exhibited a significant dose-dependent inhibition of in vitro radical scavenging assays and their corresponding IC50 values as follows: hydroxyl radical (26.50 ± 0.26 µg/ml), superoxide anion (30.00 ± 0.32 µg/ml), nitric oxide radical (48.00 ± 0.48 µg/ml), DPPH radical (30.55 ± 0.32 µg/ml) and reducing power (22.00 ± 0.22 µg/ml). The increase in the severity of DNA damage and TBARS was increased significantly (p<0.05) at 500 µM H2O2-treated cultured lymphocytes and RBC cellular membranes. The phytochemical screening studies identified 13 chemical constituents present in the leaf extract of MA.
  
  
  CONCLUSIONS
  The results of this study demonstrate that MA offers protection against H2O2-induced cellular damage and it can be developed as an effective antioxidant during oxidative stress.
authors.affiliation: Ayurveda Research Institute for Mother & Child health Care, Poojapura, Trivandrum, India.
authors.forename: Srinivasan
authors.initials: S
authors.lastname: Marimuthu
authors.forename: Padmaja
authors.initials: P
authors.lastname: Balakrishnan
authors.forename: Sudarsan
authors.initials: S
authors.lastname: Nair
mesh_terms: D000328:Adult; D002478:Cells, Cultured; D020552:Comet Assay; D019610:Cytoprotection; D004249:DNA Damage / Q000187:drug effects*; D053938:DNA Fragmentation / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D016166:Free Radical Scavengers / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D006801:Humans; D006861:Hydrogen Peroxide / Q000633:toxicity; D015227:Lipid Peroxidation / Q000187:drug effects; D008214:Lymphocytes / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D031586:Melia azedarach / Q000737:chemistry; D018384:Oxidative Stress / Q000187:drug effects; D008517:Phytotherapy; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D018515:Plant Leaves; D010946:Plants, Medicinal; D017382:Reactive Oxygen Species / Q000378:metabolism; D055815:Young Adult
chemical_list: D016166:Free Radical Scavengers; D010936:Plant Extracts; D017382:Reactive Oxygen Species; D006861:Hydrogen Peroxide