Proteome Science最新文献

Background: It has been previously shown that doxycycline (Doxy) protects the kidney from preservation injury by inhibition of matrix metalloproteinase. However, the precise molecular mechanism involved in this protection from injury is not known. We used a pharmaco-proteomics approach to identify potential molecular targets associated with kidney preservation injury.

Methods: Rat kidneys were cold perfused with or without doxycycline (Doxy) for 22 h. Kidneys perfusates were analyzed for the presence of injury markers such as lactate dehydrogenase (LDH), and neutrophil-gelatinase associated lipocalin (NGAL). Proteins extracted from kidney tissue were analyzed by 2-dimensional gel electrophoresis. Proteins of interest were identified by mass spectrometry.

Results: Triosephosphate isomerase, PGM, dihydropteridine reductase-2, pyridine nucleotide-disulfide oxidoreductase, phosphotriesterase-related protein, and aminoacylase-1A were not affected by cold perfusion. Perfusion with Doxy increased their levels. N(G),N(G)-dimethylarginine dimethylaminohydrolase and phosphoglycerate kinase 1 were decreased after cold perfusion. Perfusion with Doxy led to an increase in their levels.

Conclusions: This study revealed specific metabolic enzymes involved in preservation injury and in the mechanism whereby Doxy protects the kidney against injury during cold perfusion.

Background: Traditional studies of the cardiac proteome have mainly investigated in an animal model by two-dimensional gel electrophoresis (2-DE). However, the results have not been of satisfactory quality for an understanding of the underlying mechanism. Recent quantitative proteomic methods have been improved to overcome these limitations. To comprehensively study the cardiac proteome in a rat model of ischemia-reperfusion (IR), we developed a tandem mass tag (TMT)-based quantitative proteomic strategy. Furthermore, using this strategy, we examined the molecular mechanisms underlying the prevention of myocardial infarction by the intake of Triticum aestivum L. extract (TALE), a representative dietary fiber grain.

Methods: Cardiac proteomes were analyzed by 2-DE as a gel-based approach, and TMT labeling coupled with two-dimensional liquid chromatography (2D-LC) and tandem mass spectrometry (MS/MS) as a non-gel-based quantitative approach. Additionally, gene ontology annotation was conducted by PANTHER database. Several proteins of interest were verified by a Western blot analysis.

Results: Total 641 proteins were identified commonly from two independent MS datasets using 2D-LC MS/MS. Among these, we identified 151 IR-related proteins that were differentially expressed between the sham-operation group and IR group, comprising 62 up-regulated proteins and 89 down-regulated proteins. Most of the reduced proteins were involved in metabolic processes. In addition, 57 of the IR-related proteins were affected by TALE intake, representing 25 up-regulated proteins and 32 down-regulated proteins. In particular, TALE intake leads to a switch in metabolism to reduce the loss of high-energy phosphates and the accumulation of harmful catabolites (especially reactive oxygen species (ROS)) and to maintain cytoskeleton balance, leading to a reduction in cardiac IR injury.

Conclusions: Our study provides a comprehensive proteome map of IR-related proteins and potential target proteins and identifies mechanisms implicated in the prevention of myocardial infarction by TALE intake in a rat IR model.

Background: Irritable bowel syndrome (IBS) has been gradually recognized as a disorder of the brain-gut interaction, but the molecular changes in the brain and colon that occur in disease development remain poorly understood. We employed proteomic analysis to identify differentially expressed proteins in both the brain and colon of three IBS models.

Methods: To explore the relevant protein abundance changes in the brain and colon, isobaric tags for relative and absolute quantitation (iTRAQ), liquid chromatography and tandem mass spectrometry (LC-MS) and Western blotting methods were used in three IBS models, including maternal separation (MS, group B), chronic wrap restraint stress (CWRS, group C) and a combination of MS and CWRS (group D).

Results: We identified 153, 280, and 239 proteins that were common and differentially expressed in the two tissue types of groups B, C and D, respectively; 43 differentially expressed proteins showed the same expression changes among the three groups, including 25 proteins upregulated in the colon and downregulated in the brain, 7 proteins downregulated in the colon and upregulated in the brain, and 3 proteins upregulated and 8 downregulated in both tissues. Gene ontology analysis showed that the differentially expressed proteins were mainly associated with cellular assembly and organization and cellular function and maintenance. Protein interaction network and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis indicated that the differentiated proteins were mainly involved in the protein ubiquitination pathway and mitochondrial dysfunction.

Conclusions: Taken together, the data presented represent a comprehensive and quantitative proteomic analysis of the brain and colon in IBS models, providing new evidence of an abnormal brain-gut interaction in IBS. These data may be useful for further investigation of potential targets in the diagnosis and treatment of IBS.

Background: ALKBH7 is a mitochondrial protein, involved in programmed necrosis, fatty acid metabolism, cell cycle regulation, and prostate cancer disease. However, the exact roles of ALKBH7 and the underlying molecular mechanisms remain mysterious. Thus, investigations of the interactome and proteomic responses of ALKBH7 in cell lines using proteomics strategies are urgently required.

Methods: In the present study, we investigated the interactome of ALKBH7 in mitochondria through immunoprecipitation-mass spectrometry/mass spectrometry (IP-MS/MS). Additionally, we established the ALKBH7 knockdown and overexpression cell lines and further identified the differentially expressed proteins (DEPs) in these cell lines by TMT-based MS/MS. Two DEPs (UQCRH and HMGN1) were validated by western blotting analysis.

Results: Through bioinformatic analysis the proteomics data, we found that ALKBH7 was involved in protein homeostasis and cellular immunity, as well as cell proliferation, lipid metabolism, and programmed necrosis by regulating the expression of PTMA, PTMS, UQCRH, HMGN1, and HMGN2. Knockdown of ALKBH7 resulted in upregulation of UQCRH and HMGN1 expression, and the opposite pattern of expression was detected in ALKBH7 overexpression cell lines; these results were consistent with our proteomics data.

Conclusion: Our findings indicate that the expression of UQCRH and HMGN1 is regulated by ALKBH7, which provides potential directions for future studies of ALKBH7. Furthermore, our results also provide comprehensive insights into the molecular mechanisms and pathways associated with ALKBH7.

Chronic Kidney Disease (CKD) is a global health problem annually affecting millions of people around the world. It is a comprehensive syndrome, and various factors may contribute to its occurrence. In this study, it was attempted to provide an accurate definition of chronic kidney disease; followed by focusing and discussing on molecular pathogenesis, novel diagnosis approaches based on biomarkers, recent effective antigens and new therapeutic procedures related to high-risk chronic kidney disease such as membranous glomerulonephritis, focal segmental glomerulosclerosis, and IgA nephropathy, which may lead to end-stage renal diseases. Additionally, a considerable number of metabolites and proteins that have previously been discovered and recommended as potential biomarkers of various CKD_s using '-omics-' technologies, proteomics, and metabolomics were reviewed.

Background: Polypterus senegalus can fully regenerate its pectoral lobed fins, including a complex endoskeleton, with remarkable precision. However, despite the enormous potential of this species for use in medical research, its regeneration mechanisms remain largely unknown.

Methods: To identify the differentially expressed proteins (DEPs) during the early stages of lobed fin regeneration in P. senegalus, we performed a differential proteomic analysis using isobaric tag for relative and absolute quantitation (iTRAQ) approach based quantitative proteome from the pectoral lobed fins at 3 time points. Furthermore, we validated the changes in protein expression with multiple-reaction monitoring (MRM) analysis.

Results: The experiment yielded a total of 3177 proteins and 15,091 unique peptides including 1006 non-redundant (nr) DEPs. Of these, 592 were upregulated while 349 were downregulated after lobed fin amputation when compared to the original tissue. Bioinformatics analyses showed that the DEPs were mainly associated with Ribosome and RNA transport, metabolic, ECM-receptor interaction, Golgi and endoplasmic reticulum, DNA replication, and Regulation of actin cytoskeleton.

Conclusions: To our knowledge, this is the first proteomic research to investigate alterations in protein levels and affected pathways in bichirs' lobe-fin/limb regeneration. In addition, our study demonstrated a highly dynamic regulation during lobed fin regeneration in P. senegalus. These results not only provide a comprehensive dataset on differentially expressed proteins during the early stages of lobe-fin/limb regeneration but also advance our understanding of the molecular mechanisms underlying lobe-fin/limb regeneration.

Background: Non-alcoholic fatty liver disease (NAFLD) is caused by excessive accumulation of fat within the liver, leading to further severe conditions such as non-alcoholic steatohepatitis (NASH). Progression of healthy liver to steatosis and NASH is not yet fully understood in terms of process and response. Hepatic oxidative stress is believed to be one of the factors driving steatosis to NASH. Oxidative protein modification is the major cause of protein functional impairment in which alteration of key hepatic enzymes is likely to be a crucial factor for NAFLD biology. In the present study, we aimed to discover carbonylated protein profiles involving in NAFLD biology in vitro.

Methods: Hepatocyte cell line was used to induce steatosis with fatty acids (FA) in the presence and absence of menadione (oxidative stress inducer). Two-dimensional gel electrophoresis-based proteomics and dinitrophenyl hydrazine derivatization technique were used to identify carbonylated proteins. Sequentially, in order to view changes in protein carbonylation pathway, enrichment using Funrich algorithm was performed. The selected carbonylated proteins were validated with western blot and carbonylated sites were further identified by high-resolution LC-MS/MS.

Results: Proteomic results and pathway analysis revealed that carbonylated proteins are involved in NASH pathogenesis pathways in which most of them play important roles in energy metabolisms. Particularly, carbonylation level of ATP synthase subunit α (ATP5A), a key protein in cellular respiration, was reduced after FA and FA with oxidative stress treatment, whereas its expression was not altered. Carbonylated sites on this protein were identified and it was revealed that these sites are located in nucleotide binding region. Modification of these sites may, therefore, disturb ATP5A activity. As a consequence, the lower carbonylation level on ATP5A after FA treatment solely or with oxidative stress can increase ATP production.

Conclusions: The reduction in carbonylated level of ATP5A might occur to generate more energy in response to pathological conditions, in our case, fat accumulation and oxidative stress in hepatocytes. This would imply the association between protein carbonylation and molecular response to development of steatosis and NASH.