Protective effect of Cyclolepis genistoides aqueous extract against cellular oxidative stress

The development of neuroprotective agents constitutes one of the most promising strategies to treat neurodegenerative disorders, such as Parkinson’s disease (PD). Oxidative stress (OS) is a major contributor to the death of dopaminergic neurons in PD. In the present work, we investigated the in vitro effect of aqueous extracts of three Argentinian medicinal plants, Agalinis genistifolia (Cham. & Schltdl.) D'Arcy, Cyclolepis genistoides Gillies ex D. Don and Margyricarpus pinnatus (Lam.) Kuntze, on metal-induced OS. These species have been traditionally used to treat PD-related symptoms, such as paralysis for A. genistifolia, and inflammation for C. genistoides and M. pinnatus. To evaluate the potential neuroprotective activity of the aqueous extracts, we used the human neuroblastoma cell line IMR-32 exposed to ferric ammonium citrate (FAC) as OS inducer. Whereas cells exposed to FAC exhibited increased levels of reactive oxygen species (ROS) after the treatment with A. genistifolia and M. pinnatus (50 µg/ml extract), the exposure to C. genistoides extract at 20 µg/ml showed a reduction of ROS levels. In line with this finding, we found that C. genistoides treatment decreased lipid peroxidation under the same conditions (20 µg/ml). Furthermore, the induction of ROS production by manganese in IMR-32 cells and by FAC in N27 rat dopaminergic cells was attenuated by the exposure to C. genistoides extract. Our results suggest that the aqueous extract of C. genistoides has potential as source of neuroprotective agents than can target OS, a hallmark of neuronal death in PD.