Evidence of biological activity of Mentha species extracts on apoptotic and autophagic targets on murine RAW264.7 and human U937 monocytic cells.
CONTEXT
Mints (Lamiaceae) are used as traditional remedies for the treatment of several diseases. Their extracts are recognized as anti-inflammatory compounds.


OBJECTIVE
This study characterized the cytotoxic effects of Mentha spicata L. (MS), Mentha pulegium L. (MP) and Mentha rotundifolia (L). Huds (MR) on macrophage cells (RAW264.7; U937) and determined their impact on apoptosis and autophagy, which can play a role in controlling inflammation.


MATERIALS AND METHODS
The extracts were prepared in culture medium and tested from 25 to 400 μg/mL after 24-48 h of treatment. To show the effect of the aqueous ethanol (50%) extracts on apoptosis and authophagy, the presence of cleaved caspase-3, and the conversion of LC3-I to LC3-II was evaluated by Western blotting.


RESULTS
Compared with the MTT assay, crystal violet showed a pronounced decrease in the number of cells with all extracts at 48 h. Calculated IC50 values were 257.31, 207.82 and 368.02 μg/mL for MS, MP and MR, respectively. A significant increase in PI positive cells was observed with all extracts at 200-400 μg/mL. Mitochondrial dysfunctions and nuclear morphological changes were detected with MS and MR extracts at 400 μg/mL. At this concentration, no cleaved caspase-3 was found whereas stabilized caspase-3 in its dimeric form was identified. MS and MR extracts also favour LC3-I to LC3-II conversion which is a criterion of autophagy.


CONCLUSIONS
The cytotoxic profiles depend on the extracts considered; MS extract showed the strong activity. However, all the mint extracts studied interact with the apoptotic and autophagic pathways at elevated concentrations.
['Brahmi|Fatiha|F|', 'Hadj-Ahmed|Samia|S|', 'Zarrouk|Amira|A|', 'Bezine|Maryem|M|', 'Nury|Thomas|T|', 'Madani|Khodir|K|', 'Chibane|Mohamed|M|', 'Vejux|Anne|A|', 'Andreoletti|Pierre|P|', 'Boulekbache-Makhlouf|Lila|L|', 'Lizard|Gérard|G|']
D000818:Animals D000893:Anti-Inflammatory Agents D017209:Apoptosis D001343:Autophagy D053148:Caspase 3 D002470:Cell Survival D004305:Dose-Response Relationship, Drug D006801:Humans D020128:Inhibitory Concentration 50 D008264:Macrophages D053078:Membrane Potential, Mitochondrial D027541:Mentha D051379:Mice D008869:Microtubule-Associated Proteins D009000:Monocytes D008517:Phytotherapy D010936:Plant Extracts D010946:Plants, Medicinal D000067996:RAW 264.7 Cells D013997:Time Factors D020298:U937 Cells
Mentha spicata mentha pulegium mentha rotundifolia mitochondria