Potent protecting effects of Catuaba (Anemopaegma mirandum) extracts against hydroperoxide-induced cytotoxicity.

Ishigami et al. (Ishigami et al., 1998) reported that squalene monohydroperoxide (SQOOH) induced skin damage in hairless mice. Kohno and Takahashi (Kohno and Takahashi, 1993) reported that SQOOH induced cytotoxicity against Chinese hamster lung fibroblasts. We have already evaluated the efficacy of extracts obtained from Brazilian herbal medicines in protecting the normal human epidermis keratinocytes [NHEK(B)] against the cytotoxicity caused by SQOOH. The EtOAc extract was separated by silica-gel column chromatography into eight fractions. Fractions (Fr) 1,3 and 5 significantly protected rat basophilic leukemia (RBL-2H3) cells from the release of beta-hexosaminidase due to SQOOH. Additionally, Fr5-1 was most effective in a Gunze three-dimensional cultured human skin model (Vitrolife-skin) against the cytotoxicity due to SQOOH and the release of interleukin (IL)-2 and IL-4. The mixture of cinchonains Ia and Ib and the mixture of cinchonains IIa and IIb were isolated from Fr3 and Fr5-1, respectively. The results suggest that the addition of SQOOH caused the reduction in cell viability and the release of beta-hexosaminidase and cytokines as chemical mediators. The extract of Catuaba (Anemopaegma mirandum) prevented these toxic effects with the main active agents suggested to be cinchonains IIa and IIb.