Project description:Previously published results from our double-blind, placebo-controlled parallel study with docosahexaenoic acid (DHA) supplementation (3 g/d, 90 d) to hypertriglyceridemic men (39-66yr) showed that DHA reduced several risk factors for cardiovascular disease (CVD), including the plasma concentration of inflammatory markers. To determine the effect of DHA supplementation on the global gene expression pattern, we performed Affymetrix GeneChip microarray analysis of blood cells (treated with lipopolysaccharide (LPS) or vehicle) drawn before and after the supplementation from the hyperlipidemic men who participated in the previous study. Genes that were significantly differentially regulated by the LPS treatment and DHA supplementation were identified. Differential regulation of 18 genes was then confirmed by quantitative RT-PCR. Both microarray and qRT-PCR data showed that the expression of LDL receptor (LDLR), oxidized LDL receptor (OLR1), and cathepsin L1 (CTSL) was significantly suppressed by DHA supplementation; however, LPS stimulated the expression of LDLR and CTSL but not that of OLR1. LPS up-regulated and DHA suppressed the expression of prostaglandin E synthase (PTGES), PPAR delta, and various chemokines. Enrichment with Gene Ontology categories demonstrated that the genes related to transcription factor activity, immune responses, host defense responses, inflammatory responses, and apoptosis were inversely regulated by LPS and DHA. These results provide supporting evidence for the anti-inflammatory effects of DHA supplementation, and reveal previously unrecognized genes that are regulated by DHA, and are associated with risk factors of cardiovascular diseases. Double-blind, placebo-controlled parallel study with DHA supplementation to hypertriglyceridemic men. Gene expression detected in LPS-stimulated (LPS) and unstimulated (vehicle) white blood cells. 3-4 replicates per group.
Project description:Previously published results from our double-blind, placebo-controlled parallel study with docosahexaenoic acid (DHA) supplementation (3 g/d, 90 d) to hypertriglyceridemic men (39-66yr) showed that DHA reduced several risk factors for cardiovascular disease (CVD), including the plasma concentration of inflammatory markers. To determine the effect of DHA supplementation on the global gene expression pattern, we performed Affymetrix GeneChip microarray analysis of blood cells (treated with lipopolysaccharide (LPS) or vehicle) drawn before and after the supplementation from the hyperlipidemic men who participated in the previous study. Genes that were significantly differentially regulated by the LPS treatment and DHA supplementation were identified. Differential regulation of 18 genes was then confirmed by quantitative RT-PCR. Both microarray and qRT-PCR data showed that the expression of LDL receptor (LDLR), oxidized LDL receptor (OLR1), and cathepsin L1 (CTSL) was significantly suppressed by DHA supplementation; however, LPS stimulated the expression of LDLR and CTSL but not that of OLR1. LPS up-regulated and DHA suppressed the expression of prostaglandin E synthase (PTGES), PPAR delta, and various chemokines. Enrichment with Gene Ontology categories demonstrated that the genes related to transcription factor activity, immune responses, host defense responses, inflammatory responses, and apoptosis were inversely regulated by LPS and DHA. These results provide supporting evidence for the anti-inflammatory effects of DHA supplementation, and reveal previously unrecognized genes that are regulated by DHA, and are associated with risk factors of cardiovascular diseases.
Project description:<p>Statin drugs lower blood cholesterol levels for cardiovascular disease prevention. Women are more likely than men to experience adverse statin effects, particularly new-onset diabetes (NOD) and muscle weakness. Here we find that impaired glucose homeostasis and muscle weakness in statin-treated female mice are associated with reduced levels of the omega-3 fatty acid, docosahexaenoic acid (DHA), impaired redox tone, and reduced mitochondrial respiration. Statin adverse effects are prevented in females by administering fish oil as a source of DHA, by reducing dosage of the X chromosome or the Kdm5c gene, which escapes X chromosome inactivation and is normally expressed at higher levels in females than males. As seen in female mice, we find that women experience more severe reductions than men in DHA levels after statin administration, and that DHA levels are inversely correlated with glucose levels. Furthermore, induced pluripotent stem cells from women who developed NOD exhibit impaired mitochondrial function when treated with statin, whereas cells from men do not. These studies identify X chromosome dosage as a genetic risk factor for statin adverse effects and suggest DHA supplementation as a preventive co-therapy. </p>
Project description:The omega-3 fatty acid docosahexaenoic acid (DHA) has potent anti-atherogenic properties but its mechanisms of action at the vascular level remain poorly explored. Knowing the broad range of molecular targets of omega-3 fatty acids, microarray analysis was used to open-mindedly evaluate the effects of DHA on aorta gene expression in LDLR-/- mice and better understand its local anti-atherogenic action . Mice were fed an atherogenic diet and received daily oral gavages with oils rich in oleic acid or DHA. Bioinformatics analysis of microarray data first identified inflammation and innate immunity as processes the most affected by DHA supplementation within aorta. More precisely, several down-regulated genes were associated with the inflammatory functions of macrophages (e.g. CCL5, CCR7), cell movement (e.g. ICAM-2, SELP, PECAM-1), and the major histocompatibility complex (e.g. HLA-DQA1, HLA-DRB1). Interestingly, the expression of several genes were identified as specifc biomarkers of macrophage polarization and their changes suggested a preferential orientation towards a M2 reparative phenotype. This observation was supported by the upstream regulator analysis highlighting the involvment of three main regulators of macrophage polarization, namely PPARM-NM-3 (z-score=2.367, p=1.50x10-13), INFM-NM-3 (z-score=-2.797, p=2.81x10-14) and NFM-NM-:B (z-score=2.360, p=6.32x10-9). Moreover, immunohistological analysis of aortic root revealed an increased abundance of Arg1 (+111%, p=0.01), a specific biomarker of M2 macrophage.The present study showed for the first time that DHA supplementation during atherogenesis is associated with protective modulation of inflammation and innate immunity pathways within aorta putatively through the orientation of plaque macrophages towards a M2 reparative phenotype. Mice (LDLR-/-) Aorta samples. 2 groups: Control (K), DHA (C). Biological replicates=8. Dye switch.
Project description:Gene expression profiling of immortalized human mesenchymal stem cells with hTERT/E6/E7 transfected MSCs. hTERT may change gene expression in MSCs. Goal was to determine the gene expressions of immortalized MSCs.
Project description:Transcriptional profiling of human mesenchymal stem cells comparing normoxic MSCs cells with hypoxic MSCs cells. Hypoxia may inhibit senescence of MSCs during expansion. Goal was to determine the effects of hypoxia on global MSCs gene expression.
Project description:Gene methylation profiling of immortalized human mesenchymal stem cells comparing HPV E6/E7-transfected MSCs cells with human telomerase reverse transcriptase (hTERT)- and HPV E6/E7-transfected MSCs. hTERT may increase gene methylation in MSCs. Goal was to determine the effects of different transfected genes on global gene methylation in MSCs.
Project description:Kynureninase is a member of a large family of catalytically diverse but structurally homologous pyridoxal 5'-phosphate (PLP) dependent enzymes known as the aspartate aminotransferase superfamily or alpha-family. The Homo sapiens and other eukaryotic constitutive kynureninases preferentially catalyze the hydrolytic cleavage of 3-hydroxy-l-kynurenine to produce 3-hydroxyanthranilate and l-alanine, while l-kynurenine is the substrate of many prokaryotic inducible kynureninases. The human enzyme was cloned with an N-terminal hexahistidine tag, expressed, and purified from a bacterial expression system using Ni metal ion affinity chromatography. Kinetic characterization of the recombinant enzyme reveals classic Michaelis-Menten behavior, with a Km of 28.3 +/- 1.9 microM and a specific activity of 1.75 micromol min-1 mg-1 for 3-hydroxy-dl-kynurenine. Crystals of recombinant kynureninase that diffracted to 2.0 A were obtained, and the atomic structure of the PLP-bound holoenzyme was determined by molecular replacement using the Pseudomonas fluorescens kynureninase structure (PDB entry 1qz9) as the phasing model. A structural superposition with the P. fluorescens kynureninase revealed that these two structures resemble the "open" and "closed" conformations of aspartate aminotransferase. The comparison illustrates the dynamic nature of these proteins' small domains and reveals a role for Arg-434 similar to its role in other AAT alpha-family members. Docking of 3-hydroxy-l-kynurenine into the human kynureninase active site suggests that Asn-333 and His-102 are involved in substrate binding and molecular discrimination between inducible and constitutive kynureninase substrates.