Antamanide, a Derivative of Amanita phalloides, Is a Novel Inhibitor of the Mitochondrial Permeability Transition Pore
Figure 6
Effect of AA on HeLa cell viability.
A, cytofluorimetric analysis of cell death induction in HeLa cells treated for 1 hour with TAT-HK. Where indicated, cells were preincubated for 30 minutes with CsA or AA. TAT-Ctr was used as a negative control. Cells were double stained with Annexin V-FITC and propidium iodide (PI), to respectively evaluate apoptosis induction as phosphatidylserine exposure on the cell surface (increased Annexin V-FITC staining) and cell death as plasma membrane permeabilization (increased PI staining). We considered Annexin V+ as early/intermediate apoptotic cells; PI+ as necrotic cells; double stained as late apoptotic cells. Bar graphs display the percentage of each cell population (mean±SD, n = 4; double positive cells are added to both bars). The number of PI+ cells was significantly increased by TAT-HK treatment (Student's t test analysis; #: p<0.01 when comparing untreated and TAT-HK treated HeLa cells). Moreover, HeLa cell pretreatment with either AA or CsA significantly protected from TAT-HK induced death (Student's t test analysis; *: p<0.01 when comparing TAT-HK treated HeLa cells pretreated or not with either AA or CsA). B, histograms reporting a representative experiment, where viable cells are indicated in red, PI+- and Annexin V+-cells are indicated in grey and green, respectively.