Adipose-derived autotaxin regulates inflammation and steatosis associated with diet-induced obesity.

Autotaxin (ATX) is a secreted enzyme that generates the bioactive lipid lysophosphatidic acid (LPA). We generated mice with global inducible post-natal inactivation or adipose-specific loss of the Enpp2 gene encoding ATX. The animals are phenotypically unremarkable and exhibit differences in adipocyte size and adipose tissue expression of inflammatory genes after high fat feeding without gross differences in fat distribution or body mass. Surprisingly, both models of Enpp2- deficiency exhibited marked protection from high fat diet-induced hepatic steatosis. This phenotype was not associated with differences in dietary fat absorption but may be accounted for by differences in hepatic expression of genes involved in de novo synthesis of triglycerides. These findings suggest that pharmacological inhibition of ATX might be protective against hepatic steatosis.

Measurement of Lysophosphatidic Acid and Sphingosine-1-Phosphate by Liquid Chromatography-Coupled Electrospray Ionization Tandem Mass Spectrometry.

Lysophosphatidic acids and sphingosine-1-phosphate are bioactive lipids that regulate diverse cellular and physiological processes through actions that are largely mediated by cell surface receptors. The roles played by these lipids in multiple disease processes make the enzymes and receptors involved in their synthesis, inactivation, and signaling attractive targets for pharmacological therapies. In this chapter we describe methods for sensitive accurate quantitation of LPA and S1P levels in biological fluids using liquid chromatography-coupled electrospray ionization tandem mass spectrometry.

A FACS Based Case Study on Two HbE-ß Thalassaemia Members of a Family, Having Similar Mutational Background.

In this report we have tried to explain the reasons behind the difference in the pattern of transfusion requirement between two members of a family with similar ß-globin mutation. The father and younger son both are HbE-ß, but the father never had transfusion, whereas the younger son takes transfusion monthly. Mother and the elder son are HbEE without any history of transfusion. ß-globin mutations of all family members were determined by ARMS-PCR. These were reconfirmed by direct sequencing of ß-globin gene. Father and younger son were found to be Cod 26 (G-A)/IVS 1-5 (G-C), whereas mother and elder son were found to be Cod 26 (G-A)/Cod 26 (G-A). XmnI sequencing also revealed that all members of the family were CC. Then, flow cytometry study of red blood cells (RBCs) was performed to measure the oxidative stress of the RBCs. This study was also done on the light and dense fractions of the RBC population of the father and younger son. It was seen that the younger son suffers severe oxidative stress, which can be explained by his higher transfusion requirement. From our work, we have established the importance of taking oxidative stress of RBCs into consideration to explain the clinical manifestation and progression of haemoglobin related diseases like thalassaemia.

Erythrocyte and platelet proteomics in hematological disorders.

Erythrocytes undergo ineffective erythropoesis, hemolysis, and premature eryptosis in sickle cell disease and thalassemia. Abnormal hemoglobin variants associated with hemoglobinopathy lead to vesiculation, membrane instability, and loss of membrane asymmetry with exposal of phosphatidylserine. This potentiates thrombin generation resulting in activation of the coagulation cascade responsible for subclinical phenotypes. Platelet activation also results in the release of microparticles, which express and transfer functional receptors from platelet membrane, playing key roles in vascular reactivity and activation of intracellular signaling pathways. Over the last decade, proteomics had proven to be an important field of research in studies of blood and blood diseases. Blood cells and its fluidic components have been proven to be easy systems for studying differential expressions of proteins in hematological diseases encompassing hemoglobinopathies, different types of anemias, myeloproliferative disorders, and coagulopathies. Proteomic studies of erythrocytes and platelets reported from several groups have highlighted various factors that intersect the signaling networks in these anucleate systems. In this review, we have elaborated on the current scenario of anucleate blood cell proteomes in normal and diseased individuals and the cross-talk between the two major constituent cell types of circulating blood.

Differential regulation of urine proteins in urothelial neoplasm.

Urothelial neoplasm of the urinary bladder has a high rate of multifocality and recurrence. To understand this we first need to understand the changes in the molecular level that distinguishes a normal individual from a patient and also a low grade neoplasm from a high grade. In this work we aim to study the urine proteome of Indian patients with urothelial neoplasm categorised on the basis of their p53 immunohistochemistry. The urine samples of pre-operative patients were subjected to two dimensional gel electrophoresis followed by densitometric analysis and spot identification using MALDI mass spectrometry. Our study shows that few proteins such as albumin, alpha 1 antitrypsin, apolipoprotein A1, transferrin, transthyretin, haptoglobin and haemoglobin ß chain were upregulated and inter alpha trypsin inhibitor heavy chain was downregulated in the disease samples. Further we have reported that some of these proteins show an association with disease severity. The present study marks the first step in the identification of new diagnostic markers as well as therapeutic targets. BIOLOGICAL SIGNIFICANCE: Bladder carcinoma is the ninth most common cancer worldwide. It has gained attention within both clinicians and cancer biologists because of its recurrence and mortality rate. Identifying the prognostic factors of progression is a challenge, so that high risk patients who may be a candidate for a radical cystectomy may be identified. In this study we have attempted to study the changes observed in the urinary protein levels of urothelial neoplasm patients. The samples were graded based on p53 immunohistochemistry staining. We have reported eight (8) proteins, mostly highly abundant; those have exhibited differential regulation in case of diseased samples. This study is first of its kind that associates the changes in the urinary protein levels to that of the severity of the disease. We believe that the findings can be used as a stepping stone in the development of a noninvasive prognostic tool for the disease. This article is part of a Special Issue entitled: Proteomics in India.

Differential expression of red cell proteins in hemoglobinopathy.

Red blood cell proteome has not been studied well until recently, as the large abundance of hemoglobin posed challenge to the detection of other cytosolic proteins in the linear dynamic range. However, in the last couple of years, due to emergence of various novel hemoglobin depletion strategies and more state-of-the-art detection techniques, a number of works on erythrocyte proteome have appeared in the literature. As a result, we now have much deeper information about both the membrane as well as the cytosolic proteins of erythrocytes. In this review, we have discussed the role of red cell proteome on the two most well-studied hemoglobin disorders, sickle cell disease and thalassemia, emphasizing on the differential expression of the redox regulator proteins and chaperones, in particular. We have also touched upon the importance of the association of the varying levels of hemoglobin variants, particularly HbE on the clinical manifestation of composite diseases like HbEß thalassemia.