Effects of Pelargonium Sidoides Extract on Apoptosis and Oxidative Stress in Human Neuroblastoma Cells

Background and Objectives: Neuroblastoma is the most common extracranial solid tumor in children, often presenting challenges in treatment due to its clinical and genetic heterogeneity. This study investigated the anticancer potential of Pelargonium sidoides root extract on the human neuroblastoma cell line (SH-SY5Y). Using XTT assays, ELISA-based oxidative stress markers, and RT-PCR analysis of apoptotic genes, the study explored the extract's effects on cell proliferation, oxidative stress, and apoptosis. Materials and Methods: For the cell culture, SH-SY5Y human neuroblastoma cells were thawed, cultured, and maintained under appropriate conditions for experiments. The dose- and time-dependent activity of Pelorgonium sidoides extract on SH-SY5Y neuroblastoma cells was investigated by XTT assay. The change in the oxidative stress marker 8-Hydroxy-2'-deoxyguanosine (8-OhDG) level was determined by ELISA for the doses applied to the control group root extract at a concentration of 25 μg/mL. Total antioxidant status (TAS) and total oxidant status (TOS) were measured from the cells in the study group with the help of a commercial kit. The oxidative stress index (OSI) was calculated by dividing the TAS by the TOS and multiplying by 100. In order to evaluate the expression levels of apoptosis-related Bax, Bcl-2, Caspase-3, Caspase-8, and Caspase-9 genes at the mRNA level in control and dose group cells, RNA isolation was performed from the SH-SY5Y control and dose group cells (IC50 value). Results: It is observed that the P. sidoides substance inhibits proliferation in cells at 24 h (p < 0.05). As the dose increases, cell proliferation decreases (p < 0.05). The IC50 value was calculated to be 113.83 μg/mL at 24 h. The concentration of 8-OhDG increased in neuroblastoma cells as a result of P. sidoides extract treatment (p < 0.05). TOS levels increased in neuroblastoma cells treated with P. sidoides extract (p < 0.01). OSI levels increased in cells treated with P. sidoides extract (p < 0.001). BAX and Caspase-8 expression increased are statistically significant in the P. sidoides dose group (p < 0.05). Conclusions: P. sidoides extract induces apoptosis in neuroblastoma cells through oxidative stress and mitochondrial- and death receptor-mediated pathways. This study highlights the potential of P. sidoides as a complementary therapeutic agent for neuroblastoma, warranting further in vivo and clinical investigations to assess its safety and efficacy.