Potential biomarkers of an exaggerated response to endotoxemia

Mass Spectrometry-Based Analysis of Time-Resolved Proteome Quantification

The aspect of time is essential in biological processes and thus it is important to be able to monitor signaling molecules through time. Proteins are key players in cellular signaling and they respond to many stimuli and change their expression in many time-dependent processes. Mass spectrometry (MS) is an important tool for studying proteins, including their posttranslational modifications and their interaction partners-both in qualitative and quantitative ways. In order to distinguish the different trends over time, proteins, modification sites, and interacting proteins must be compared between different time points, and therefore relative quantification is preferred. In this review, the progress and challenges for MS-based analysis of time-resolved proteome dynamics are discussed. Further, aspects on model systems, technologies, sampling frequencies, and presentation of the dynamic data are discussed.

Development and Characterization of an Endotoxemia Model in Zebra Fish

Endotoxemia is a condition in which endotoxins enter the blood stream and cause systemic and sometimes lethal inflammation. Zebra fish provides a genetically tractable model organism for studying innate immunity, with additional advantages in live imaging and drug discovery. However, a bona fide endotoxemia model has not been established in zebra fish. Here, we have developed an acute endotoxemia model in zebra fish by injecting a single dose of LPS directly into the circulation. Hallmarks of human acute endotoxemia, including systemic inflammation, extensive tissue damage, circulation blockade, immune cell mobilization, and emergency hematopoiesis, were recapitulated in this model. Knocking out the adaptor protein Myd88 inhibited systemic inflammation and improved zebra fish survival. In addition, similar alternations of pathways with human acute endotoxemia were detected using global proteomic profiling and MetaCore™ pathway enrichment analysis. Furthermore, treating zebra fish with a protein tyrosine phosphatase nonreceptor type 11 (Shp2) inhibitor decreased systemic inflammation, immune mobilization, tissue damage, and improved survival in the endotoxemia model. Together, we have established and characterized the phenotypic and gene expression changes of a zebra fish endotoxemia model, which is amenable to genetic and pharmacological discoveries that can ultimately lead to a better mechanistic understanding of the dynamics and interplay of the innate immune system.

Application of clinical proteomics in acute respiratory distress syndrome

Acute Respiratory Distress Syndrome (ARDS) is a devastating cause of hypoxic respiratory failure, which continues to have high mortality. It is expected that a comprehensive systems- level approach will identify global and complex changes that contribute to the development of ARDS and subsequent repair of the damaged lung. In the last decade, powerful genome-wide analytical and informatics tools have been developed, that have provided valuable insights into the mechanisms of complex diseases such as ARDS. These tools include the rapid and precise measure of gene expression at the proteomic level. This article reviews the contemporary proteomics platforms that are available for comprehensive studies in ARDS. The challenges of various biofluids that could be investigated and some of the studies performed are also discussed.

Updates on apolipoprotein CIII: fulfilling promise as a therapeutic target for hypertriglyceridemia and cardiovascular disease

PURPOSE OF REVIEW

The lipid hypothesis of atherosclerosis is mainly predicated on the function of apolipoprotein (apo)B lipoproteins, which promote atherosclerosis, and apoA lipoproteins, which prevent it. However, accumulating evidence suggests causal roles of other apolipoproteins, abundant surface components of apoB and apoA lipoprotein, in promoting atherosclerosis and other metabolic diseases. This article reviews recent literature on one such apolipoprotein: apoCIII.

RECENT FINDINGS

Population studies have consistently demonstrated that plasma apoCIII strongly predicts cardiovascular disease. ApoCIII's atherogenicity was traditionally attributed to hypertriglyceridemia because of its inhibition on the lipolysis of triglyceride-rich lipoproteins. Recent evidence expands this function and reveals apoCIII's key role in hepatic assembly and secretion of triglyceride-rich lipoproteins. In addition to these indirect atherogenic functions mediated through dyslipidemia, recent research discovers that apoCIII directly provoke proinflammatory responses in vascular cells, including monocytes and endothelial cells. These direct atherogenic effects are dependent on apoCIII. ApoCIII is also involved in pancreatic beta-cell biology and contributes to type I diabetes.

SUMMARY

Recent data further strengthen the theory that apoCIII exerts strong atherogenic functions through both indirect and direct mechanisms. Encouraging results from early stage clinical trials demonstrate that modulating apoCIII per se is a novel and potent therapeutic approach to managing dyslipidemia and cardiovascular disease risk.