EXTRACTS FROM Nicotiana glauca INDUCE APOPTOSIS THROUGH CASPASES IN SKELETAL MUSCLE CELLS

Phytoestrogens are plant compounds which have generated considerable interests. A litany of health benefits including a lowered risk of osteoporosis, heart disease, breast cancer, and menopausal symptoms, are frequently attributed to phytoestrogens but without the knowledge of their side effects. Consequently, the question of whether or not phytoestrogens are beneficial or harmful to human health remains unresolved. Here, we investigate the effects of lipid extracts from the Solanaceae Nicotiana glauca on skeletal muscle cells, in relation to apoptosis. Previously, we evidenced the presence of molecules functional and structurally analogous to 17β-estradiol in extracts of Solanaceaes.  We performed extraction and phytochemical screening as per the standard methods of Wagner (1984), using Dragendroff’s, Bornträger´s and Libermann-Burchard’s test.  The effects of lipids extracts from N. glauca in C2C12 cells were analyzed by Mitotracker DAPI, TUNEL and immunofluorescence staining and Western blotting. Caspase activity was analyzed with a commercial kit.

Opposite to the effects of 17β-estradiol, the crude extract from N. glauca and its sub-extracts obtained by partition, induced apoptosis in C2C12 cells. This apoptotic action involved caspase 3/7 activation. Also, we evidenced that the extracts from N. glauca trigger a rapid defense response in skeletal muscle through Akt and HSP27-phosphorylation. The data reported here, on the effects of lipid extracts from N. glauca on myoblasts suggest that the traditional use of this medicinal plant could affect the skeletal muscle homeostasis.