Temporal Change of Extracellular Matrix during Vein Arterialization Remodeling in Rats.

The global expression profile of the arterialized rat jugular vein was established to identify candidate genes and cellular pathways underlying the remodeling process. The arterialized jugular vein was analyzed on days 3 and 28 post-surgery and compared with the normal jugular vein and carotid artery. A gene array platform detected 9846 genes in all samples. A heatmap analysis uncovered patterns of gene expression showing that the arterialized vein underwent a partial transition from vein to artery from day 3 to 28 post-surgery. The same pattern was verified for 1845 key differentially expressed genes by performing a pairwise comparison of the jugular vein with the other groups. Interestingly, hierarchical clustering of 60 genes with altered expression on day 3 and day 28 displayed an expression pattern similar to that of the carotid artery. Enrichment analysis results and the network relationship among genes modulated during vein arterialization showed that collagen might play a role in the early remodeling process. Indeed, the total collagen content was increased, with the augmented expression of collagen I, collagen IV, and collagen V in arterialized veins. Additionally, there was an increase in the expression of versican and Thy-1 and a decrease in the expression of biglycan and ß1-integrin. Overall, we provide evidence that vein arterialization remodeling is accompanied by consistent patterns of gene expression and that collagen may be an essential element underlying extracellular matrix changes that support the increased vascular wall stress of the new hemodynamic environment.

Development of a pharmacogenetic-based warfarin dosing algorithm and its performance in Brazilian patients: highlighting the importance of population-specific calibration.

BACKGROUND: The main aims of the present study were to develop a pharmacogenetic-based warfarin dosing algorithm and to validate it in a highly admixed population. MATERIALS & METHODS: We included two patient cohorts treated with warfarin (first cohort, n = 832; and second cohort, n = 133). RESULTS: Our algorithm achieved a determination coefficient of 40% including the variables age, gender, weight, height, self-declared race, amiodarone use, enzyme inducers use, VKORC1 genotypes and predicted phenotypes according to CYP2C9 polymorphisms. CONCLUSION: Data suggest that our developed algorithm is more accurate than the IWPC algorithm when the application is focused on patients from the Brazilian population. Population-specific derivation and/or calibration of warfarin dosing algorithms may lead to improved performance compared with general use dosing algorithms currently available. Original submitted 26 November 2014; Revision submitted 9 April 2015.

PBMCs express a transcriptome signature predictor of oxygen uptake responsiveness to endurance exercise training in men.

Peripheral blood cells are an accessible environment in which to visualize exercise-induced alterations in global gene expression patterns. We aimed to identify a peripheral blood mononuclear cell (PBMC) signature represented by alterations in gene expression, in response to a standardized endurance exercise training protocol. In addition, we searched for molecular classifiers of the variability in oxygen uptake (V̇o2). Healthy untrained policemen recruits (n = 13, 25 ± 3 yr) were selected. Peak V̇o2 (measured by cardiopulmonary exercise testing) and total RNA from PBMCs were obtained before and after 18 wk of running endurance training (3 times/wk, 60 min). Total RNA was used for whole genome expression analysis using Affymetrix GeneChip Human Gene 1.0 ST. Data were normalized by the robust multiarray average algorithm. Principal component analysis was used to perform correlations between baseline gene expression and V̇o2peak. A set of 211 transcripts was differentially expressed (ANOVA, P < 0.05 and fold change > 1.3). Functional enrichment analysis revealed that transcripts were mainly related to immune function, cell cycle processes, development, and growth. Baseline expression of 98 and 53 transcripts was associated with the absolute and relative V̇o2peak response, respectively, with a strong correlation (r > 0.75, P < 0.01), and this panel was able to classify the 13 individuals according to their potential to improve oxygen uptake. A subset of 10 transcripts represented these signatures to a similar extent. PBMCs reveal a transcriptional signature responsive to endurance training. Additionally, a baseline transcriptional signature was associated with changes in V̇o2peak. Results might illustrate the possibility of obtaining molecular classifiers of endurance capacity changes through a minimally invasive blood sampling procedure.