Apoptotic Potential of Artemsia sieberia Besser (Asteraceae) Fraction against Human Cancer Cell Lines

Purpose: To investigate the anti-proliferative and apoptotic activity of crude and dichloromethane fraction of A. sieberi against seven cancer cell lines (Colo20, HCT116, DLD, MCF7, Jurkat, HepG2 and L929).Methods: A. sieberi was extracted with methanol and further purification was carried out using liquidliquid extraction with hexane, dichloromethane and ethyl acetate. Each extract was assayed for cytotoxic potential against cancer cell lines using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium Bromide (MTT) assay. The morphology of the HepG2 cell nucleus was investigated by Hoechst 33342, DNA-binding dye. A Tali™ image-based cytometer was used to assess cell viability, death and apoptosis using annexin-v /pi (propidium iodide). A chromatographic fingerprint was constructed using high performance liquid chromatography (HPLC).Results: The most effective anticancer activity of the unrefined methanol extract was against HepG2 cell lines (LC50 = 161.5 μg/mL). The hexane and ethyl acetate fractions showed no antiproliferative activity. The dichloromethane fraction displayed higher cytotoxic activity (LC50 = 61.75 μg/mL) and also repressed the migration of the cells. About 50 % of HepG2 cells were apoptotic when treated for 24 h with the dichloromethane fraction at the concentration of 120 μg/mLConclusion: A. sieberi possesses apoptotic activity and inhibited the migration of the HepG2 cell lines.Keywords: Artemsia Sieberia, Apoptosiss, Cytotoxicity, Hoescht staining, HepG2 cell line

Ultrastructure of antennal sensillae of the samsum ant, Pachycondyla sennaarensis (Hymenoptera: Formicidae)

Black ant (Samsum), Pachycodyla sennarrensis, stings and injects venom and inflicts allergy (a rare clinical problem) due to its local and systemic reaction, which is considered as a health hazard amongst Saudi society. Thus, black ant is a source of serious concern for the government and experts as well.  Ultramorphological variations, distribution, differential sensillae counts (DSC) and total sensillae counts (TSC), were identified and estimated as a complementary part of the peripheral nervous system on the antennae of worker samsum ant, P. sennarrensis in order to understand its behavioral ecology. Based on scanning electron micrographs, four types of sensillae constituted with three trichoid types, which is an abundant form with a high distribution density at the apex, but a low density at subsequent proximal flagellomere of the antenna and a placoid type of sensillae (a rare form mostly found in the middle of the flagellum, that is, on the 4th, 5th and 6th flagellomere) were categorised. It is documented that nonporous trichoid type of sensillae are mechanoreceptors and thermoreceptors, whereas, the placoid types are olfactory receptors. Present findings in an indigenous species in Saudi Arabia may help in understanding the ecological behaviour of the ant, which subsequently may form the basis in producing its effective control measure in future.Key words: Samsum ants, Pachycondyla sennarrensis, ultrastructure, antenna, sensillae