Protective effects of guarana (Paullinia cupana Mart. var. Sorbilis) against DEN-induced DNA damage on mouse liver

Food Chem Toxicol. 2006 Jun;44(6):862-7. doi: 10.1016/j.fct.2005.11.010. Epub 2006 Jan 9.


Guarana (Paullinia cupana Mart. var. Sorbilis) is a plant originally from Brazil, which is rich in tannins. Some tannins are known to present protective effects against DNA damage. This study was performed to investigate the anti-genotoxic/cytotoxic properties of guarana in hepatocytes of mice injected with N-nitrosodiethylamine (DEN). The protective effect of guarana was evaluated both by comet assay and DNA smear fragmentation technique in two month-old female BALB/c mice. These were treated previously with 2.0 mg/g bw of guarana for 16 days and then injected with DEN (160 microg/g body weight) to induce DNA damage. The DEN-only treated group presented higher comet image length than the guarana plus DEN and untreated groups (116.06+/-5.0 microm, 104.09+/-3.3 microm and 93.28+/-14.4 microm, respectively; p<0.01). Guarana treatment presented a 52.54% reduction in comet image length when animals were exposed to DEN (p<0.05). DNA samples from the guarana plus DEN group clearly showed less EtBr fluorescence intensity when compared to the DEN-only group, reinforcing the comet assay data. These results show, for the first time, that guarana has a protective effect against DEN-induced DNA damage in mouse liver.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alkylating Agents / pharmacology*
  • Animals
  • Comet Assay
  • DNA Damage / drug effects*
  • DNA Fragmentation
  • Diet*
  • Diethylnitrosamine / pharmacology*
  • Female
  • Liver / chemistry*
  • Mice
  • Mice, Inbred BALB C
  • Paullinia* / chemistry
  • Tannins / pharmacology


  • Alkylating Agents
  • Tannins
  • Diethylnitrosamine