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Arachidonic acid metabolites are a family of bioactive lipids derived from membrane phospholipids. They are involved in cancer progression, but arachidonic acid metabolite profiles and their related biosynthetic pathways remain uncertain in colorectal cancer (CRC). To compare the arachidonic acid metabolite profiles between CRC patients and healthy controls, quantification was performed using a liquid chromatography-mass spectrometry-based analysis of serum and tissue samples. Metabolomics analysis delineated the distinct oxidized lipids in CRC patients and healthy controls. Prostaglandin (PGE2)-derived metabolites were increased, suggesting that the PGE2 biosynthetic pathway was upregulated in CRC. The qRT-PCR and immunohistochemistry analyses showed that the expression level of PGE2 synthases, the key protein of PGE2 biosynthesis, was upregulated in CRC and positively correlated with the CD68+ macrophage density and CRC development. Our study indicates that the PGE2 biosynthetic pathway is associated with macrophage infiltration and progression of CRC tumors. [ABSTRACT FROM AUTHOR]

Glycosylation is an important mechanism of secondary protein processing. Large-scale profiling of glycopeptides released by proteolytic digestion of glycoproteins from biologic samples with complex compositions is limited due to their low abundance. Herein, we present a multimodal material based on boronic acid-modified mesoporous magnetic particles with a hydrophilic surface and enlarged pores around 10 nm. Multimodal enrichment successfully improved the enrichment specificity and efficiency of BMMP by synergistic interaction of hydrophilicity and boronic acid functional groups. The 10 nm pore size allows glycopeptides to enter the channel. Hydrophilic glycopeptides could be selectively enriched with an extremely low limit of detection (0.33 fmol per μL) and a high selectivity (1 : 100). From 2 μL of human serum, 328 unique glycopeptides from 101 glycoproteins were identified. A total of 33% of those glycoproteins overlapped with FDA-cleared blood serum biomarkers. It is expected that BMMP in the future can be used for large-scale biomedical glycoproteomics studies. [ABSTRACT FROM AUTHOR]

Lipid mediators (LMs) play a pivotal role in the induction and resolution of inflammation. To identify and elucidate their involvement during virus infection, multiple reaction monitoring (MRM) based liquid chromatography–tandem mass spectrometry lipidomic profiling of 62 lipid species was performed in this study. Results show that RAW264.7 macrophages differentially produce specific LMs signals depending on difference in virus pathogenicity. Integration of large-scale lipidomics with targeted gene expression data revealed mediators, such as RVD3, 18-HEPE, 11(12)-EET etc. correlated with the pathogenic phase of the infection. The herpes simplex virus (HSV)-induced keratitis model demonstrates that 11(12)-EET treatment represents a novel alternative for treating viral infection. [ABSTRACT FROM AUTHOR]

There are thousands of lipid species existing in cells, which belong to eight different categories. Lipids are the essential building blocks of cells. Recent studies have started to unveil the important functions of lipids in regulating cell metabolism. However, we are still at a very early stage in fully understanding the physiological and pathological functions of lipids. The application of lipidomics for studying lipid metabolism can provide a direct readout of the cellular status and broadens our understanding of the mechanisms that underpin metabolic disease states. This review provides an introduction to lipid metabolism and its role in modulating homeostasis and immunity. We also describe representative applications of lipidomics for studying lipid metabolism in inflammation-related diseases. [ABSTRACT FROM AUTHOR]

As a key post-translational modification mechanism, protein acetylation plays critical roles in regulating and/or coordinating cell metabolism. Acetylation is a prevalent modification process in enzymes. Protein acetylation modification occurs in sub-stoichiometric amounts; therefore extracting biologically meaningful information from these acetylation sites requires an adaptable, sensitive, specific, and robust method for their quantification. In this work, we combine immunoassays and multiple reaction monitoring-mass spectrometry (MRM-MS) technology to develop an absolute quantification for acetylation modification. With this hybrid method, we quantified the acetylation level of metabolic enzymes, which could demonstrate the regulatory mechanisms of the studied enzymes. The development of this quantitative workflow is a pivotal step for advancing our knowledge and understanding of the regulatory effects of protein acetylation in physiology and pathophysiology. [ABSTRACT FROM AUTHOR]