Oxidized phospholipids-induced apoptosis

Truncated Oxidized Phospholipids Induce Apoptosis in Vascular Smooth Muscle Cells... 

Fig. 13.3 Signaling pathways involved in oxidized phospholipid-induced apoptosis in mammalian smooth muscle and endothelial cells. AIF, apoptosis inducing factor Apaf-1, apoptosis activating factor 1 aSM, acid sphingomyelinase Az-PC azelaoyl acid ester of lyso-PC Cyt c, cytochrome c G-PC, glutaric acid ester of lyso-PC IM, intermembrane space of the mitochondria JNK, c-Jun N-terminal kinase OV-PC, 5-oxovaleric acid ester of lyso-PC p38, p38 mitogen-activated protein kinase PM, plasma membrane...

Since in all these cases we used oxidants to induce apoptosis, a relatively massive background oxidation of all PnA-labeled phospholipid classes was observed and masked apoptosis-specific PS oxidation. Therefore, we next determined whether a non-oxidant-induced apoptosis model could be used to reveal more explicitly the selective mode of PS oxidation inherent to the apoptosis execution program. To this end, we used agonistic anti-Fas antibody to induce apoptosis in Jurkat B cells according to a commonly used protocol (Fadeel et al., 1999). Importantly, we foundthat anti-Fas-triggered apoptosis in Jurkat cells was characterized by early and selective oxidaiton of cA-PnA-PS (Kagan et al., 2001) without any significant involvement of other classes of phospholipids. 

Fruhwirth, G O, Moumtzi, A, Loidl, A, Ingolic, E, and Hermetter, A, The oxidized phospholipids POVPC and PGPC inhibit growth and induce apoptosis in vascular smooth muscle cells, Biochim. Biophys. Acta - Molecular and Cell Biology of Lipids 1761 (2006) 1060-1069. 

Using this protocol we found that apoptosis induced by a number of different oxidants is associated with selective oxidation of specific phospholipid classes, most notably PS (Kagan et al, 2000, Tyurina et al,... 

In this manuscript we review the recent literature reporting on apoptosis inducing glycerophospholipids. In addition, we describe the cellular processes that lead to phospholipid oxidation as part of the apoptotic mode of cell death and are likely to enhance the recognition of apoptotic cells by phagocytic macrophages. 

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