Roberto Angelini

Swansea University | SWAN · Medical School - Institute of Life Science

Cardiolipin (CL), a dimeric phospholipid carrying four fatty acid chains in its structure, is the lipid marker of mitochondria, wherein it plays a crucial role in the functioning of the inner membrane. Its metabolite monolysocardiolipin (MLCL) is physiologically nearly absent in the lipid extract of animal cells and its appearance is the hallmark o...

Despite being a critical molecule in the brain, mass spectrometry imaging (MSI) of cholesterol has been under-reported compared to other lipids due to the difficulty in ionizing the sterol molecule. In the present work, we have employed an on-tissue enzyme-assisted derivatization strategy to improve detection of cholesterol in brain tissue sections...

Objective: Cachexia is a complex metabolic syndrome frequently occurring in cancer patients and exacerbated by chemotherapy. In skeletal muscle of cancer hosts, reduced oxidative capacity and low intracellular ATP resulting from abnormal mitochondrial function were described. Methods: The present study aimed at evaluating the ability of the mitocho...

Despite being a critical molecule for neurobiology and brain health, mass spectrometry imaging (MSI) of cholesterol has been under reported compared to other lipids, due to the difficulty in ionising the sterol molecule. In the present work we have employed an on-tissue enzyme-assisted derivatisation strategy to improve detection of cholesterol in...

Dysregulated cholesterol metabolism is implicated in a number of neurological disorders. Many sterols, including cholesterol and its precursors and metabolites, are biologically active and important for proper brain function. However, spatial cholesterol metabolism in brain and the resulting sterol distributions are poorly defined. To better unders...

Lipidomics can be regarded as the quantitative profiling of the entire lipid composition of a defined system, be that a cell, tissue, biofluid or intact organism. Lipidomics is a descendent of what was previously known as “metabolite profiling” and is a relative of the related “omic” disciplines of genomics, transcriptomics and proteomics. Lipidomi...

Dysregulated cholesterol metabolism is implicated in a number of neurological disorders. Many sterols, including cholesterol and its precursors and metabolites, are biologically active and important for proper brain function. However, spatial cholesterol metabolism in brain and the resulting sterol distributions are poorly defined. To better unders...

Cross-presentation is a critical function of dendritic cells (DCs) required for induction of antitumor immune responses and success of cancer immunotherapy. It is established that tumor-associated DCs are defective in their ability to cross-present antigens. However, the mechanisms driving these defects are still unknown. We find that impaired cros...

Experimental approach: We investigated the potential of URB937 to reduce the establishment of lithium chloride (LiCl)-induced conditioned gaping (a model of acute nausea) and to reduce the expression of contextually elicited conditioned gaping (a model of anticipatory nausea) in rats. As well, the role of CB1 receptors, CB2 receptors and the perox...

Introduction: Fatty acid ethanolamides (FAEs) are a family of lipid mediators that participate in a host of biological functions. Procedures for the quantitative analysis of FAEs include organic solvent extraction from biological matrices (e.g., blood), followed by purification and subsequent quantitation by liquid chromatography–mass spectrometry...

Detection, identification, characterization and quantitation of oxidized cardiolipin forms in vivo is considered a challenging task, because these lipid species exist in low abundance in the biological systems. Recently it has been shown that chain-shortened products of oxidized standard phosphatidylcholines could be successfully identified by matr...

Barth syndrome, an X-linked disease associated with cardioskeletal myopathy, neutropenia and organic aciduria, is characterized by abnormalities of cardiolipin species in mitochondria. Diagnosis of the disease is often compromised by lack of rapid and widely available diagnostic laboratory tests. The present study describes a new method for Barth s...

Lipids of cytochrome c oxidase (COX) of Paracoccus denitrificans have been identified by MALDI-TOF/MS direct analyses of isolated protein complexes, avoiding steps of lipid extraction or chromatographic separation. Two different COX preparations have been considered in the present study: the enzyme core consisting of subunits I and II (COX-2SU) and...

We report changes of the content of anionic phospholipids in Bacillus subtilis in response to hypoxic conditions and inhibition of terminal respiration. Cardiolipin accumulates rapidly when bacteria are suspended in non-growth medium under reduced aeration or exposed to the inhibitor cyanide; the increase of cardiolipin occurs at the expense of its...

MALDI-TOF signals of phospholipids of B. subtilis control cells.

The lipidome of the marine hyperthermophilic archaeon Pyrococcus furiosus was studied by means of combined thin-layer chromatography and MALDI-TOF/MS analyses of the total lipid extract. 80-90% of the major polar lipids were represented by archaeol lipids (diethers) and the remaining part by caldarchaeol lipids (tetraethers). The direct analysis of...

The lipid composition of Halobacillus halophilus was investigated by combined thin-layer chromatography and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analyses of the total lipid extract. Main polar lipids were found to be sulfoquinovosyldiacylglycerol and phosphatidylglycerol, while cardiolipin was a minor lipid t...

A simple and fast method of lipid analysis of isolated intact mitochondria by means of MALDI-TOF mass spectrometry is described. Mitochondria isolated from bovine heart and yeast have been employed to set up and validate the new method of lipid analysis. The mitochondrial suspension is directly applied over the target and, after drying, covered by...

Squarebop I bacteriorhodopsin is a light-activated proton pump present in the membranes of the archeon Haloquadratum walsbyi, a square-shaped organism representing 50-60% of microbial population in the crystallizer ponds of the coastal salterns. Here we describe: (1) the operating mode of a bioreactor designed to concentrate the saltern biomass thr...

The lipidome of two extremely haloalkaliphilic archaea, Natronococcus occultus and Natronococcus amylolyticus, has been examined by means of combined thin-layer chromatography and MALDI-TOF/MS analyses. The detailed investigation of lipid profiles has confirmed the presence of i) ether lipid phosphatidylglycerol and phosphatidylglycerophosphate met...

The GL15 glioblastoma cell line undergoes viability loss upon treatment with bromopyruvate. The biochemical mechanisms triggered by the antiglycolytic agent indicate the activation of an autophagic pathway. Acridine orange stains acidic intracellular vesicles already 60 min after bromopyruvate treatment, whereas autophagosomes engulfing electron de...

Mass spectrometry analysis of the lipid extracts of saltern biomass represents a powerful tool to quickly obtain information on the presence of various archaeal and bacterial microorganisms in saltern ponds. In the last years, ESI-MS lipid profiling by a shotgun lipidomic approach has allowed the discovery of new lipid molecules in the membranes of...

A method of direct lipid analysis by MALDI mass spectrometry in intact membranes, without prior extraction/separation steps, is described. The purple membrane isolated from the extremely halophilic archaeon Halobacterium salinarum was selected as model membrane. Lyophilized purple membrane were grinded with 9-aminoacridine (9-AA) as dry matrix, and...

The use of the matrix 9-aminoacridine has been recently introduced in matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry analysis of both anionic and cationic phospholipids. In the present study, we take advantage of this technique to analyze the lipids of porcine olfactory mucosa and a membrane fraction enrich...