Cystathionine β-synthase deficiency: different changes in proteomes of thrombosis-resistant Cbs−/− mice and thrombosis-prone CBS−/− humans

Abstract

Cystathionine β-synthase (CBS)-deficient patients are prone to vascular thrombosis. In contrast, Cbs −/− mice show no abnormalities in blood coagulation. To identify molecular basis underlying these disparately different thrombotic phenotypes, we analyzed plasma proteomes of Cbs −/− vs. Cbs +/+ mice (8-month-old, 12/group, sex-matched) and CBS −/− vs. CBS +/+ humans (37 ± 7-year-old, 10-14/ group, sex-matched) using label-free mass spectrometry. We identified 117 and 41 differentiating plasma proteins in Cbs −/− mice and CBS −/− humans, respectively. Twenty-one proteins were shared between CBS −/− humans and Cbs −/− mice, with sixteen changed in the opposite direction. Proteins involved in blood coagulation and complement/coagulation cascades represented a greater fraction of the differentiating proteins in CBS −/− patients (51%) than in Cbs −/− mice (21%). Top canonical pathways, identified by Ingenuity Pathways Analysis, such as LXR/RXR, FXR/RXR activation (− log[P-value] = 30-31) and atherosclerosis signaling (− log[P-value] = 10-11) were similarly affected in Cbs −/− mice and CBS −/− humans. The Coagulation System was affected stronger in CBS −/− humans than in Cbs −/− mice (− log[P-value] = 15 vs. 10, respectively) while acute phase response and complement system were affected stronger in Cbs −/− mice (− log[P-value] = 33 and 22, respectively) than in humans (− log[P-value] = 22 and 6, respectively). Other pathways, including IL-7 signaling and B cell development were affected only in Cbs −/− mice. Taken together, our findings suggest that differences in these processes, in particular in the Coagulation System, could account for the thrombotic phenotype in CBS −/− patients and the absence of thrombosis in Cbs −/− mice. Overall, our findings suggest that Cbs −/− mice have a better adaptive response to protect from prothrombotic effects of hyperhomocysteinemia than CBS −/− humans. Patients with cystathionine β-synthase (CBS) deficiency, a rare inborn error of metabolism caused by mutations in the CBS gene, have severely elevated levels of the sulfur-amino acid homocysteine (Hcy) 1 and its metabolites 2. The only known source of Hcy in the human body is the dietary protein methionine, which is converted to Hcy in a sequence of three consecutive reactions with AdoMet and AdoHcy as intermediates. Hcy is further metabolized via three pathways, affording cysteine, methionine, or Hcy-thiolactone 3. The metabolic conversion of Hcy to cysteine is impaired in CBS-deficient patients, causing severe hyperhomocysteinemia (HHcy) 1 and

Genetic Attenuation of Paraoxonase 1 Activity Induces Proatherogenic Changes in Plasma Proteomes of Mice and Humans

“…Datasets were imported into MaxQuant 1.5.3.30 version. Proteins were identified using UniProt human/mouse database with a precision tolerance 10 ppm for peptide masses and 0.08 Da for fragment ion masses as previously described [25]. The MaxQuant data were filtered for reverse identifications (false positives), contaminants, and proteins "only identified by site".…”

“…Ten micrograms of human or mouse plasma protein were diluted in 50 mM ammonium bicarbonate (15 µL), reduced with dithiothreitol (5.5 mM, 5 min, 95 • C), and alkylated with iodoacetamide (5 mM, 20 min, 25 • C, in the dark). Proteins were digested with Promega sequencing-grade trypsin (0.2 µg, overnight, 37 • C), separated using the Dionex UltiMate 3000 RSLC nanoLC System and analyzed using Q Exactive Orbitrap mass spectrometer (Thermo Fisher Scientific) as previously described [25].…”

“…T-test was used for comparisons between two groups with p values < 0.05 considered significant. Multivariate analyses were carried out by untargeted principal component analysis (PCA) [25].…”

“…The datasets containing differentially expressed proteins were uploaded into the IPA Knowledge database. Biological pathways and networks involving PON1 genotype-affected proteins were identified using the Ingenuity Pathway Analysis resources (IPA, Ingenuity Systems, Mountain View, CA, USA) as previously described [25].…”

L-Metiyoninin Neden Olduğu Nörokognitif Yıkılma: Bir Nörodejenerasyon Fare Modeli

“…Homosistein, bulunduğu ortamda sahip olduğu sülfür bağı nedeniyle çevresindeki moleküllerle artmış elektron alışverişinde bulunarak Red/Ox dengesini bozmaktadır (30). Bu durum bu aminoasitin çok farklı patofizyolojik yolaklarda etkili olmasına neden olmaktadır (31).…”