5.3.1. Panax ginseng C.A. Mey

Polysaccharides from P. ginseng, among the most widely known and used medicinal plant, have been already shown promising anti-proliferative effects against several cancer cell lines (Sun, 2011). In 2017, Liao and coworkers synthesized a Se-P deriving from an aqueous extract of ginseng roots obtaining a Se content of 1.54 mg /g. The growth inhibitory effects of this Se-P were first investigated in vitro using the HL-60 (human leukemia) cell line. Cells were incubated for 24–72 h with increasing concentrations of the Se-P in the range 25–400 μg/mL. The best results have been obtained after 48 h with applied doses of 50 μg/ mL, 100 μg/mL, and 200 μg/mL leading to a reduction of surviving cells in the range 34.2%–53.6%. These concentration levels were then selected to perform further tests. The next parameter evaluated was the release of LDH, well established to be a signal of apoptotic induction and progress. The administration of Se-P provided a dose-dependent increase of LDH release. HL-60 cells were also morphologically examined. The group treated with the Se-P at 200 μg/mL was characterized by cell shrinkage, condensed nuclei, and fragmented cell membranes. Furthermore, the induction of apoptosis occurred at a mithochondrial level with changes in the trans -membrane potential, activation of pro-caspase 9, in turn leading to cleavage of caspase 9, caspase 3, and PARP, to a dose-dependent increase of the expression of the pro-apoptotic protein Bax and in the mean time a decrease of the anti-apoptotic factor Bcl-2.