title: Antimutagenic and antioxidant activity of a protein fraction from aerial parts of Urtica dioica.
abstract: BACKGROUND
  Urtica dioica L. (Urticaceae), stinging nettle, has been employed as a folklore remedy for a wide spectrum of ailments, including urinary disorders, prostatic hyperplasia, and liver diseases. It has been also used traditionally for cancer treatment.
  
  
  OBJECTIVE
  To evaluate the potential chemopreventive properties of a protein fraction from the aerial part of Urtica dioica (namely UDHL30).
  
  
  METHODS
  UDHL30 has been tested for the antimutagenic activity in bacteria (50-800 μg/plate; Ames test by the preincubation method) and for the cytotoxicity on human hepatoma HepG2 cells (0.06-2 mg/mL; 24 and 48 h incubation). Moreover, the antioxidant activity of UDHL30 (0.1-1200 μg/mL; ABTS and superoxide-radical scavenger assays) was evaluated as potential protective mechanisms.
  
  
  RESULTS
  UDHL30 was not cytotoxic on HepG2 cells up to 2 mg/mL; conversely, it exhibited a strong antimutagenic activity against the mutagen 2-aminoanthracene (2AA) in all strains tested (maximum inhibition of 56, 78, and 61% in TA98, TA100, and WP2uvrA strains, respectively, at 800 μg/plate). In addition, a remarkable scavenging activity against ABTS radical and superoxide anion (IC50 values of 19.9 ± 1.0 μg/mL and 75.3 ± 0.9 μg/mL, respectively) was produced.
  
  
  CONCLUSIONS
  UDHL30 possesses antimutagenic and radical scavenging properties. Being 2AA a pro-carcinogenic agent, we hypothesize that the antimutagenicity of UDHL30 can be due to the inhibition of CYP450-isoenzymes, involved in the mutagen bioactivation. The radical scavenger ability could contribute to 2AA-antimutagenicity. These data encourage further studies in order to better define the potential usefulness of UDHL30 in chemoprevention.
authors.affiliation: Department of Physiology and Pharmacology "V. Erspamer", Sapienza University of Rome , Rome , Italy .
authors.forename: Antonella
authors.initials: A
authors.lastname: Di Sotto
authors.forename: Gabriela
authors.initials: G
authors.lastname: Mazzanti
authors.forename: Nijole
authors.initials: N
authors.lastname: Savickiene
authors.forename: Rasa
authors.initials: R
authors.lastname: Staršelskytė
authors.forename: Vaida
authors.initials: V
authors.lastname: Baksenskaite
authors.forename: Silvia
authors.initials: S
authors.lastname: Di Giacomo
authors.forename: Annabella
authors.initials: A
authors.lastname: Vitalone
mesh_terms: D016587:Antimutagenic Agents / Q000494:pharmacology*; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology; D000975:Antioxidants / Q000494:pharmacology*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D016166:Free Radical Scavengers / Q000494:pharmacology; D006801:Humans; D009152:Mutagenicity Tests; D018515:Plant Leaves / Q000737:chemistry; D010940:Plant Proteins / Q000494:pharmacology*; D026982:Urtica dioica / Q000737:chemistry*
chemical_list: D016587:Antimutagenic Agents; D000972:Antineoplastic Agents, Phytogenic; D000975:Antioxidants; D016166:Free Radical Scavengers; D010940:Plant Proteins
keywords: Antimutagenicity; chemoprevention; stinging nettle