Ex vivo assessment of Nerium oleander (Defla) toxicity and Silybum marianum (Khurfeish) antidotal virtues

Assessment of toxicity of plants in the Palestinian ranges and looking for antidotal range plants have vital economical, ecological and also political importance. This research aims to evaluate the toxicity of Nerium oleander (Defla) and the antitoxic capacity of Khurfeish in HepG2 cells. A series of concentrations of plant extracts were added to HepG2 and the effect was evaluated using the MTT viability and NO mortality assays. As the concentration of Defla increases, the viability of HepG2 cell line decreases to attain its minimum at 15725 μg of plant dry matter/ ml of RPMI medium using both assays. Unexpectedly, a growth enhancer effect was found at the Defla concentration of 25 μg of plant dry matter/ ml of RPMI medium using the MTT assay. Khurfeish was assessed for its antidotal effects when combined with Defla. The effect of Khurfeish alone on HepG2 cell line showed to be mitogenic. This effect is in general proportionate to the concentration of Khurfeish. When combined with Defla, Khurfeish was found to have an antidotal effect against the toxicity of Defla. Promising antidotal effects of Khurfeish were obtained when added with Defla at the following concentrations respectively (20000 and 1500, 100000 and 3000, 100000 and 9000 μg of plant dry matter/ ml of RPMI medium). The antidotal effect, in general, decreases as the concentration of Defla increases. However, at the Defla concentration of 90000 μg of plant DM/ ml of medium, Khurfeish, no longer shows anti- toxicity virtues. This might demonstrate the efficiency of treating intoxication at early stages. Based on the mentioned values and in case of intoxication of farm animals by Defla, it could be useful to counteract the toxicity by feeding with Khurfeish of about 11 to 33 equivalent of the Defla weight. For ultimate validation of these results, experiments should be conducted in vivo using small animals then farm animals.