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Carreras, A.

Publications and source records attributed to Carreras, A..

3 recordsLinked to original sources

Gut microbial metabolite imidazole propionate impairs endothelial cell function and promotes the development of atherosclerosis

BackgroundThe microbially generated amino acid-derived metabolite imidazole propionate (ImP) contributes to the pathogenesis of type 2 diabetes. However, the effect of ImP on endothelial cell physiology and its role in atherosclerotic coronary artery disease (CAD) is unknown. Using both human and animal model studies, we investigated the potential contributory role of ImP in the development of atherosclerosis. MethodsPlasma levels of ImP were measured in patients undergoing elective cardiac angiography (n = 831) by means of ultra high-performance liquid chromatography coupled to tandem mass spectrometry. Odds ratios (ORs) and corresponding 95% confidence intervals for CAD were calculated based on the ImP quartiles using both univariable and multivariable logistic regression models. Atheroprone apolipoprotein E-/- (Apoe-/-) mice fed a high-fat diet were additionally treated with ImP (800 {micro}g) or vehicle and aortic atherosclerotic lesion area was evaluated after 12 weeks. In a mouse model of carotid artery injury, the effect of ImP on vascular regeneration was examined. Using human aortic endothelial cells (HAECs) the effect of ImP on functional properties of endothelial cells were assessed. Next-generation sequencing, western blot analysis, siRNA-based gene knockdown and tamoxifen-inducible Cre-loxP experiments were performed to investigate ImP-mediated molecular mechanisms. ResultsPlasma ImP levels in subjects undergoing cardiac evaluation were associated with increased risk for prevalent CAD. In atheroprone Apoe-/- mice ImP increased atherosclerotic lesion size. We found that ImP dose-dependently impaired migratory and angiogenic properties of human endothelial cells, and promoted an increased inflammatory response. Long-term exposure to ImP impaired the repair potential of the endothelium after an arterial insult. Mechanistically, ImP attenuated insulin receptor signaling by suppressing PI3K/AKT pathway leading to the sustained activation of the forkhead box protein O1 (FOXO1) transcription factor. Genetic inactivation of endothelial FOXO1 signaling in ImP-treated mice enhanced the angiogenic activity and preserved the vascular repair capacity of endothelial cells after carotid injury. ConclusionsOur findings reveal a hitherto unknown role of the microbially produced histidine-derived metabolite ImP in endothelial dysfunction and atherosclerosis, suggesting that ImP metabolism is a potential therapeutic target in atherosclerotic cardiovascular disease.

systems biology↗

GCAT|Panel, a comprehensive structural variant haplotype map of the Iberian population from high-coverage whole-genome sequencing

The combined analysis of haplotype panels with phenotype clinical cohorts is a common approach to explore the genetic architecture of human diseases. However, genetic studies are mainly based on single nucleotide variants (SNVs) and small insertions and deletions (indels). Here, we contribute to fill this gap by generating a dense haplotype map focused on the identification, characterization and phasing of structural variants (SVs). By integrating multiple variant identification methods and Logistic Regression models, we present a catalogue of 35,431,441 variants, including 89,178 SVs ([≥]50bp), 30,325,064 SNVs and 5,017,199 indels, across 785 Illumina high coverage (30X) whole-genomes from the Iberian GCAT Cohort, containing 3.52M SNVs, 606,336 indels and 6,393 SVs in median per individual. The haplotype panel is able to impute up to 14,360,728 SNVs/indels and 23,179 SVs, showing a 2.7-fold increase for SVs compared with available genetic variation panels. The value of this panel for SVs analysis is shown through an imputed rare Alu element located in a new locus associated with mononeuritis of lower limb, a rare neuromuscular disease. This study represents the first deep characterization of genetic variation within the Iberian population and the first operational haplotype panel to systematically include the SVs into genome-wide genetic studies.

genomics↗

In vivo CRISPR-Cas gene editing with no detectable genome-wide off-target mutations

CRISPR-Cas genome-editing nucleases hold substantial promise for human therapeutics1-5 but identifying unwanted off-target mutations remains an important requirement for clinical translation6, 7. For ex vivo therapeutic applications, previously published cell-based genome-wide methods provide potentially useful strategies to identify and quantify these off-target mutation sites8-12. However, a well-validated method that can reliably identify off-targets in vivo has not been described to date, leaving the question of whether and how frequently these types of mutations occur. Here we describe Verification of In Vivo Off-targets (VIVO), a highly sensitive, unbiased, and generalizable strategy that we show can robustly identify genome-wide CRISPR-Cas nuclease off-target effects in vivo. To our knowledge, these studies provide the first demonstration that CRISPR-Cas nucleases can induce substantial off-target mutations in vivo, a result we obtained using a deliberately promiscuous guide RNA (gRNA). More importantly, we used VIVO to show that appropriately designed gRNAs can direct efficient in vivo editing without inducing detectable off-target mutations. Our findings provide strong support for and should encourage further development of in vivo genome editing therapeutic strategies.

molecular biology↗