Exploring the Antiproliferative Mechanisms of Urtica dioica L. extract in Human Promyelocytic Leukemia Cell Line

Abstract

Background: Nature is a source of therapeutic compounds which have fewer side effects compared to synthetic drugs. Stinging nettle extract, widely-used in Anatolia, has a strong antiproliferative effect on many types of cancer. However, the underlying molecular mechanisms of this effect is still not known. Materials and Methods: In this study, the interaction of Urtica dioica L. extract at different concentrations with apoptosis and autophagy pathways in the human promyelocytic cell line (HL-60) was studied to elucidate how it triggers the antiproliferative effects. In this context, firstly, the plant leaves were extracted in water with the Soxhlet extraction method. HL-60 cells were incubated with the extract at different concentrations for 24 hours, and the activated antitumoral effect pathway was investigated with advanced following molecular tests: MTT staining, Nitric oxide (NO) level, Annexin-V in flow cytometry, cell cycle, mitochondrial membrane potential measurement (MMP) and qPCR for evaluation of apoptosis and autophagy mediator genes. Results: It was determined that cell proliferation was suppressed at a concentration of 100 µg/mL and cells were kept in G0/G1 phase, MMP was impaired in cells and the rate of apoptotic cells increased. These apoptotic markers were confirmed by statistically increased expression of apoptotic and autophagy genes and NO level. Conclusions: Taken together, it is predicted that Urtica dioica L. water extract initiates apoptosis in HL-60 cells and could be promising compound candidate for cancer treatment.