No abstract

A high-lipid diet is one of the main risk factors in atherosclerosis and can induce changes in the composition of plasma membrane microdomains. In response, important functions such as vesicle trafficking, protein docking, signaling and receptor recognition are significantly altered. In particular, interactions of heat-shock proteins (Hsps), acting as danger signals, with components of the membrane microdomains can influence signaling pathways and the inflammatory response of cells. Our study focuses on the composition of detergent-resistant membrane (DRM) isolated from ApoE-/- mice fed a standard or high-fat diet with and without fluvastatin treatment versus appropriate controls. Biochemical studies, immunoblotting and liquid chromatography mass spectrometric analysis were performed to investigate whether the structural components (such as caveolin and cavin) of the detergent-resistant microdomains were correlated with the expression and secretion of stress-inducible Hsps (Hsp70 and Hsp90) and AKT phosphorylation in experimental atherosclerosis. ApoE-/- mice challenged with a high-fat diet developed extensive atherosclerotic plaques in lesion-prone areas. DRM harvested from hyperlipidemic animals showed a modified biochemical composition with cholesterol, glycerolipids, caveolin-1 and phospho-AKT being up-regulated, whereas cavin-1 and dynamin were down-regulated. The data also demonstrated the co-fractionation of Hsps with caveolin-1 in isolated DRM, expression being positively correlated with their secretion into blood serum. Statin therapy significantly attenuated the processes induced by the development of atherosclerosis in ApoE-/- mice under a high-fat diet. Thus, high-lipid stress induces profound changes in DRM biochemistry and modifies the cellular response, supporting the systemic inflammatory onset of atherosclerosis.

No abstract

Exosomes are small extracellular vesicles with a variable protein cargo in consonance with cell origin and pathophysiological conditions. Gestational diabetes mellitus (GDM) is characterized by different levels of chronic low-grade inflammation and vascular dysfunction; however, there are few data characterizing the serum exosomal protein cargo of GDM patients and associated signaling pathways. Eighteen pregnant women were enrolled in the study: 8 controls (CG) and 10 patients with GDM. Blood samples were collected from patients, for exosomes’ concentration. Protein abundance alterations were demonstrated by relative mass spectrometric analysis and their association with clinical parameters in GDM patients was performed using Pearson’s correlation analysis. The proteomics analysis revealed 78 significantly altered proteins when comparing GDM to CG, related to complement and coagulation cascades, platelet activation, prothrombotic factors and cholesterol metabolism. Down-regulation of Complement C3 (C3), Complement C5 (C5), C4-B (C4B), C4b-binding protein beta chain (C4BPB) and C4b-binding protein alpha chain (C4BPA), and up-regulation of C7, C9 and F12 were found in GDM. Our data indicated significant correlations between factors involved in the pathogenesis of GDM and clinical parameters that may improve the understanding of GDM pathophysiology. Data are available via ProteomeXchange with identifier PXD035673.

The study aimed to evaluate the proteomic changes in benign follicular adenoma versus malignant follicular variant of papillary thyroid carcinoma. Tumor and nontumor adjacent samples were analyzed by liquid nanochromatography mass spectrometry, and protein abundance was evaluated by label-free quantification. Western blotting and quantitative real-time polymerase chain reaction were used to validate and complement the mass spectrometry data. The results demonstrated deregulated expression of four endoplasmic reticulum chaperones (78 kDa glucose-regulated protein, endoplasmin, calnexin, protein disulfide-isomerase A4), glutathione peroxidase 3 and thyroglobulin, all of them involved in thyroid hormone synthesis pathway. The altered tissue abundance of endoplasmic reticulum chaperones in thyroid cancer was correlated with serum expression levels. The identified proteins significantly discriminate between adenoma and carcinoma in both thyroid tissue and corresponding sera. Data are available via ProteomeXchange with identifier PXD004322.