Oxidative Lipidomics of γ-Radiation-Induced Lung Injury: Mass Spectrometric Characterization of Cardiolipin and Phosphatidylserine Peroxidation

Abstract

Oxidative damage plays a significant role in the pathogenesis of γ-radiation-induced lung injury. Endothelium is a preferred target for early radiation-induced damage and apoptosis. Given the newly discovered role of oxidized phospholipids in apoptotic signaling, we performed oxidative lipidomics analysis of phospholipids in irradiated mouse lungs and cultured mouse lung endothelial cells. C57BL/6NHsd female mice were subjected to total-body irradiation (10 Gy, 15 Gy) and euthanized 24 h thereafter. Mouse lung endothelial cells were analyzed 48 h after γ irradiation (15 Gy). We found that radiation-induced apoptosis in vivo and in vitro was accompanied by non-random oxidation of phospholipids. Cardiolipin and phosphatidylserine were the major oxidized phospholipids, while more abundant phospholipids (phosphatidylcholine, phosphatidylethanolamine) remained non-oxidized. Electrospray ionization mass spectrometry analysis revealed the formation of cardiolipin and phosphatidylserine oxygenated molecular species in the irradiated lung and cells. Analysis of fatty acids after hydrolysis of cardiolipin and phosphatidylserine by phospholipase A2 revealed the presence of mono-hydroperoxy and/or mono-hydroxy/mono-epoxy, mono-hydroperoxy/mono-oxo molecular species of linoleic acid. We speculate that cyt c-driven oxidations of cardiolipin and phosphatidylserine associated with the execution of apoptosis in pulmonary endothelial cells are important contributors to endothelium dysfunction in γ-radiation-induced lung injury.

Alterations in phospholipidomic profile in the brain of mouse model of depression induced by chronic unpredictable stress

“…Figure 4 shows the MS/MS spectrum of the ion at m/z 697.8, which analysis and interpretation allowed the assignment of this ion as the short chain oxidation product CL- The CL hydroperoxy and hydroxy derivatives were already observed in CL oxidation in in vitro and in vivo studies (Tyurin et al, 2000, Tyurina et al, 2011. In this study, we have identified hydroxy and hydroperoxy -CL species at m/z 761.7 and 773.6 (Table 2).…”

Protein-tyrosine Phosphatase 4A3 (PTP4A3) Promotes Vascular Endothelial Growth Factor Signaling and Enables Endothelial Cell Motility

“…Primary Endothelial Cell Culture-Mouse primary endothelial cells were isolated from pulmonary tissue (n ϭ 12 mice/ genotype) as described previously (22). Cells were cultured on a collagen matrix in 2% O 2 , 5% CO 2 , 93% N 2 in a Coy hypoxic glove box/chamber (Coy Laboratories, Inc.) in Opti-MEM (Invitrogen), 10% FBS, 2 mM glutamine, 0.2% retinal derived growth factor (ENDOGRO; Vec Technologies), 10 units/ml heparin, 0.1 mM nonessential amino acid supplement (Invitrogen), and 55 M ␤-mercaptoethanol.…”

Mitochondrial Redox Opto-Lipidomics Reveals Mono-Oxygenated Cardiolipins as Pro-Apoptotic Death Signals

“…(b) Unigram frequencies of observed oxidized acyl chains upon apoptosis induction by different stimuli highlight mono-oxygenated C18:2 CL species. A, NAO-light (current work); B, actinomycin D (2012); 61 C, actinomycin D (2014); 19 D, controlled cortical impact; 19 E, gamma irradiation (2008); 22 F, gamma irradiation (2009); 57 G, gamma irradiation (2011, in vitro ); 22 H, gamma irradiation (2011, in vivo ); 22 I, hyperoxia; 60 J, mechanical injury; 58 K, actinomycin D (current work); L, rotenone (2013); 56 M, rotenone (2015); 62 N, staurosporine; 65 O, single walled carbon nanotubes; 63 and P, whole body radiation. 19 In the inset boxplot, the same frequencies are shown by grouping the stimuli as follows: NAO-light (this work) in red, in vitro (B, C, F, G, J, K, L, and N) in blue, and in vivo (D, E, H, I, M, O, and P) in green.…”