title: Effects of steep pulsed electric fields (SPEF) on mitochondrial transmembrane potential of human liver cancer cell.
abstract: Mitochondrial plays an important role in apoptosis, and measuring the change of mitochondrial transmembrane potential (delta psi m) is a useful method for apoptosis. Exposing human liver cancer cell SMMC-7721 dyed with Rhodamine 123 to steep pulsed electric fields (SPEF), this paper observed the real-time change of delta psi m using laser scanning confocal microscope (LSCM) to study the apoptosis effect of SPEF. The experiment results showed that delta psi m decreased gradually in process of exposing to SPEF, SPEF with higher voltage (600V) and shorter width (100ns) could cause a quicker decrease than SPEF with lower voltage (200V) and longer width (1.3mus). Such phenomenon kept up even after canceling SPEF, this may lead to collapse of delta psi m and induce apoptosis with tremendous possibilities. The experiment results of flow cytometry (SMMC-7721 dyed with Annexin V-FITC) approved that SPEF could induce apoptosis markedly (P<0.01); SPEF with lower voltage (200V) and longer width (1.3mus) could induce apoptosis more effectively (P<0.01) than SPEF with higher voltage (600V) and shorter width (100ns). These experiment results supply possible mechanism and parameter selection basis for tumor treatment using SPEF.
authors.affiliation: Key Laboratory of High Voltage Engineering and Electrical New Technology, Ministry of Education, Electrical Engineering College of Chongqing University, Chongqing 400044, China. miyan@cqu.edu.cn
authors.forename: Yan
authors.initials: Y
authors.lastname: Mi
authors.forename: Caixin
authors.initials: C
authors.lastname: Sun
authors.forename: Chenguo
authors.initials: C
authors.lastname: Yao
authors.forename: Chengxiang
authors.initials: C
authors.lastname: Li
authors.forename: Dengbin
authors.initials: D
authors.lastname: Mo
authors.forename: Liling
authors.initials: L
authors.lastname: Tang
authors.forename: Huan
authors.initials: H
authors.lastname: Liu
mesh_terms: D045744:Cell Line, Tumor; D004307:Dose-Response Relationship, Radiation; D004574:Electromagnetic Fields; D006801:Humans; D008113:Liver Neoplasms / Q000473:pathology* / Q000503:physiopathology*; D053078:Membrane Potential, Mitochondrial / Q000528:radiation effects*; D051336:Mitochondrial Membranes / Q000528:radiation effects*; D011829:Radiation Dosage