Antitumor and Antioxidant Activity of Different Pelargonium graveolens Crude Leaves Extracts

Pelargonium graveolens is an important medicinal plant which is traditionally used to staunch bleeding, heal wounds, ulcers and skin disorders as well as treat diarrhea and dysentery. The present study was
conducted to evaluate the anti-oxidant and anti-tumor properties of P.graveolens leaves collected from Baghdad, Iraq.Methanol, di-ethyl ether and hexane extract from P. graveolens. The antioxidant activity of P. graveolens extracts from methanol, di-ethyl ether and hexane were assessed using DPPH at concentrations ranged from 75 to 1000µg/ml. The methanolic extract of P. graveolens reduced the oncentration of DPPH free radicals in a dose-dependent manner with IC  up to 484µg/ml, while di-ethyl ether and hexane extracts showed a lower scavenging activity with IC 50  of 872 and 883µg/ml respectively.
The anti-tumor activity of methanol, di-ethyl ether and hexane extracts of P. graveolens on MCF-7 and PC-3 tumor cell lines were investigated in vitro using MTT assy. The methanolic extract showed the highest anti-tumor activity and reduction in cell viability against MCF-7 in a dose-dependent pattern in which the methanolic extract significantly exhibit the most potent anti-tumor activity with IC  value of 288µg/ml, whereas IC 50  values of di-ethyl ether and hexane were 822 and 415µg/ml,respectively. No significant anti-tumor activity was recorded against PC3 cell line.The effect of P. graveolens methanolic extract on MCF-7 cell line regarding viability, cell nucleus morphology, membrane permeability,potential mitochondrial permeability, cytochrome C release and ROS generation were further verified using High Content Screening array scan with multi-parametric kit and ROS kit. Results indicated that the methanolic extract of P. graveolens dose-dependently inhibited the cell growth of MCF-7 cells with a maximum inhibition of 53.92% at 200µg/ml. The intensity of cell membrane permeability was also increased in a dose-dependent pattern by increasing the extract concentration, while only higher concentrations caused alterations in nucleus morphology. On the other hand, only at higher concentration (200µg/ml) of P. graveolens methanolic extract caused reduction in mitochondrial membrane potential by 40.3% in which the disruption of mitochondrial membrane potential in consequence resulted in the release of the mitochondrial cytochrome C, which was significantly detected by 0.7 fold increases in the average fluorescent intensity of the treated MCF-7 cells than that of untreated cells. Methanolic extract treatment at higher concentrations (100 and 200µg/ml) also resulted in reactive oxygen species(ROS)generation,0.53 fold and 1.32 fold increase, respectively, as compared with untreated MCF-7 cells.