Cytotoxic effect of p-Coumaric acid on neuroblastoma, N2a cell via generation of reactive oxygen species leading to dysfunction of mitochondria inducing apoptosis and autophagy.
p-Coumaric acid (p-CA), an ubiquitous plant phenolic acid, has been proven to render protection against pathological conditions. In the present study, p-CA was evaluated for its capacity to induce cytotoxic effect to neuroblastoma N2a cells and we report here the possible mechanism of its action. p-CA at a concentration of 150 μmol/L, upon exposure for 72 h, stimulated 81.23 % of cells to apoptosis, as evidenced by flow cytometer studies mediated through elevated levels of ROS (7.5-fold over control). Excess ROS production activated structural injury to mitochondrial membrane, observed as dissipation of its membrane potential and followed by the release of cytochrome c (8.73-fold). Enhanced generation of intracellular ROS correlated well with the decreased levels (~60 %) of intracellular GSH. Sensitizing neuroblastoma cells for induction of apoptosis by p-CA identified p53-mediated upregulated accumulation of caspase-8 messenger RNA (2.8-fold). Our data report on autophagy, representing an additional mechanism of p-CA to induce growth arrest, detected by immunoblotting and fluorescence, correlated with accumulation of elevated levels (1.2-fold) of the LC3-II protein and acridine orange-stained autophagosomes, both autophagy markers. The present study indicates p-CA was effective in production of ROS-dependent mitochondrial damage-induced cytotoxicity in N2a cells.
Institution of Excellence, Vijnana Bhavana, University of Mysore, Mysore, 570006, India, shailasree_s@yahoo.co.uk.
S
S
Shailasree
M
M
Venkataramana
S R
SR
Niranjana
H S
HS
Prakash
D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D001343:Autophagy / Q000187:drug effects*; D015415:Biomarkers / Q000378:metabolism; D053181:Caspase 8 / Q000235:genetics / Q000378:metabolism; D045744:Cell Line, Tumor; D048430:Cell Shape / Q000187:drug effects; D003373:Coumaric Acids / Q000737:chemistry* / Q000633:toxicity; D045304:Cytochromes c / Q000378:metabolism; D005434:Flow Cytometry; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D005978:Glutathione / Q000378:metabolism; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D051379:Mice; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism*; D009447:Neuroblastoma / Q000201:enzymology / Q000235:genetics / Q000473:pathology*; D011422:Propionates; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism*; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism; D015854:Up-Regulation / Q000187:drug effects
D015415:Biomarkers; D003373:Coumaric Acids; C480860:Map1lc3b protein, mouse; D008869:Microtubule-Associated Proteins; D011422:Propionates; D012333:RNA, Messenger; D017382:Reactive Oxygen Species; D016159:Tumor Suppressor Protein p53; D045304:Cytochromes c; D053181:Caspase 8; D005978:Glutathione; C495469:p-coumaric acid