Project description:The GEMINAL Study- Gene Expression Modulation by Intervention with Nutrition and Lifestyle We conducted a pilot study to examine changes in gene expression in men diagnosed with low risk prostate cancer who participated in an intensive nutrition and lifestyle intervention. We profiled gene expression in morphologically normal tissues from prostate biopsies of all 30 participants before and after the intervention. Keywords: Differential gene expression analysis Pre-intervention versus Post-Intervention
Project description:The GEMINAL Study- Gene Expression Modulation by Intervention with Nutrition and Lifestyle We conducted a pilot study to examine changes in gene expression in men diagnosed with low risk prostate cancer who participated in an intensive nutrition and lifestyle intervention. We profiled gene expression in morphologically normal tissues from prostate biopsies of all 30 participants before and after the intervention. Keywords: Differential gene expression analysis
Project description:The objective of this study was to examine relationships between weight loss through changes in lifestyle and peripheral blood gene expression profiles. Substantial weight loss (-15.2+3.8%) in lifestyle participants was associated with improvement in selected cardiovascular risk factors and significant changes in peripheral blood gene expression from pre- to post-intervention: 132 unique genes showed significant expression changes related to immune function and inflammatory responses involving endothelial activation. In contrast, participants losing minimal weight (-3.1+2.5%) showed only minor changes in cardiovascular risk factors and markers of inflammation, and no changes in gene expression compared to non-intervention controls after 1 year. Weight loss (>10%) during lifestyle modification is associated with down-regulation of genetic pathways governing interactions between circulating immune cells and the vascular endothelium and may be required to successfully reduce CVD risk. A prospective nonrandomized trail was conducted over 1 year in participants undergoing intensive lifestyle modification to reverse or stabilize progression of coronary artery disease. Cardiovascular risk factors, inflammatory biomarkers, and gene expression as a function of weight loss were assessed in 89 lifestyle participants and 71 retrospectively matched controls undergoing usual care.
Project description:Weight loss and physical activity are the cornerstones of therapy for type 2 diabetes. However, providing an effective lifestyle intervention is difficult because of limited availability of reliable programs, patient inconvenience, and cost. A worksite setting provides a unique opportunity for lifestyle therapy because it reduces these barriers. We conducted an 8-month randomized controlled trial in persons with obesity and diabetes to determine the therapeutic effects and potential mechanisms of intensive-lifestyle-therapy (energy restriction and supervised exercise training) conducted at the worksite. Intensive-lifestyle-therapy resulted in marked (17%) weight loss, associated with beneficial changes in body composition, cardiorespiratory fitness, muscle strength, glycemic control, β-cell function and insulin sensitivity in the liver, adipose tissue, and skeletal muscle, despite a decrease in diabetes medication use. These beneficial effects were associated with changes in skeletal muscle (increased metabolite content and expression of genes involved in NAD biosynthesis, sirtuin signaling, and mitochondrial biogenesis and function), adipose tissue (decreased expression of genes involved in extracellular matrix remodeling), and a major plasma mediator of insulin resistance (decreased plasma PAI-1). These findings demonstrate that effective intensive-lifestyle-therapy can be implemented at the worksite, and has profound therapeutic, clinical, physiological, and cellular effects in people with obesity and type 2 diabetes.
Project description:Lifestyle intervention can improve insulin sensitivity in obese youth yet few studies have examined the biological mechanisms underlying improvements. Therefore, the purpose of this study was to explore biological pathways associated with intervention-induced improvements in insulin sensitivity. Fifteen (7M/8F) overweight/obese (BMI percentile=96.3M-BM-11.1) Latino adolescents (15.0M-BM-10.9 years) completed a 12-week lifestyle intervention that included weekly nutrition education and 180 minutes of moderate-vigorous exercise per week. Insulin sensitivity, estimated by an oral glucose tolerance test and the Matsuda Index, increased 29.2% post intervention (2.4M-BM-10.3 to 3.1M-BM-10.3, p=0.01). Global microarray analysis profiling from whole blood was performed to examine changes in gene expression and to explore biological pathways that were significantly changed in response to the intervention. A total of 1,459 probes corresponding to mRNA transcripts (717 up, 742 down) were differentially expressed with a fold changeM-bM-^IM-%1.2 and P<0.05. Among the genes identified were hexokinase 3 (HK3), ATPase, H+ transporting V0 subunit e2 (ATPV0E), and sterol regulatory element binding transcription factor 1 (SREBF1), and endothelial cell adhesion molecule (ESAM). There were 8 pathways identified that met the criteria for significance, including insulin signaling, type 1 diabetes, and glycerophospholipid metabolism. Participants that increased insulin sensitivity exhibited five times the number of significant genes altered compared to non-responders (1,144 vs. 230). These findings offer insight into the molecular mechanisms underlying health improvements among high-risk Latino youth. Lifestyle interventions may contribute to improved insulin sensitivity through pathways related to insulin signaling and immune response. Further, genetic factors may mediate response to lifestyle intervention. Fifteen (7M/8F) overweight/obese Latino Youth Whole blood RNA samples evaluated pre and post intervention.
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.
Project description:As the evolution of miRNA genes has been found to be one of the important factors in formation of the modern type of man, we performed a comparative analysis of the evolution of miRNA genes in two archaic hominines, Homo sapiens neanderthalensis and Homo sapiens denisova, and elucidated the expression of their target mRNAs in bain.A comparative analysis of the genomes of primates, including species in the genus Homo, identified a group of miRNA genes having fixed substitutions with important implications for the evolution of Homo sapiens neanderthalensis and Homo sapiens denisova. The mRNAs targeted by miRNAs with mutations specific for Homo sapiens denisova exhibited enhanced expression during postnatal brain development in modern humans. By contrast, the expression of mRNAs targeted by miRNAs bearing variations specific for Homo sapiens neanderthalensis was shown to be enhanced in prenatal brain development.Our results highlight the importance of changes in miRNA gene sequences in the course of Homo sapiens denisova and Homo sapiens neanderthalensis evolution. The genetic alterations of miRNAs regulating the spatiotemporal expression of multiple genes in the prenatal and postnatal brain may contribute to the progressive evolution of brain function, which is consistent with the observations of fine technical and typological properties of tools and decorative items reported from archaeological Denisovan sites. The data also suggest that differential spatial-temporal regulation of gene products promoted by the subspecies-specific mutations in the miRNA genes might have occurred in the brains of Homo sapiens denisova and Homo sapiens neanderthalensis, potentially contributing to the cultural differences between these two archaic hominines.
Project description:PurposeWe investigated the evidence of recent positive selection in the human phototransduction system at single nucleotide polymorphism (SNP) and gene level.MethodsSNP genotyping data from the International HapMap Project for European, Eastern Asian, and African populations was used to discover differences in haplotype length and allele frequency between these populations. Numeric selection metrics were computed for each SNP and aggregated into gene-level metrics to measure evidence of recent positive selection. The level of recent positive selection in phototransduction genes was evaluated and compared to a set of genes shown previously to be under recent selection, and a set of highly conserved genes as positive and negative controls, respectively.ResultsSix of 20 phototransduction genes evaluated had gene-level selection metrics above the 90th percentile: RGS9, GNB1, RHO, PDE6G, GNAT1, and SLC24A1. The selection signal across these genes was found to be of similar magnitude to the positive control genes and much greater than the negative control genes.ConclusionsThere is evidence for selective pressure in the genes involved in retinal phototransduction, and traces of this selective pressure can be demonstrated using SNP-level and gene-level metrics of allelic variation. We hypothesize that the selective pressure on these genes was related to their role in low light vision and retinal adaptation to ambient light changes. Uncovering the underlying genetics of evolutionary adaptations in phototransduction not only allows greater understanding of vision and visual diseases, but also the development of patient-specific diagnostic and intervention strategies.
Project description:Lifestyle intervention can improve insulin sensitivity in obese youth yet few studies have examined the biological mechanisms underlying improvements. Therefore, the purpose of this study was to explore biological pathways associated with intervention-induced improvements in insulin sensitivity. Fifteen (7M/8F) overweight/obese (BMI percentile=96.3±1.1) Latino adolescents (15.0±0.9 years) completed a 12-week lifestyle intervention that included weekly nutrition education and 180 minutes of moderate-vigorous exercise per week. Insulin sensitivity, estimated by an oral glucose tolerance test and the Matsuda Index, increased 29.2% post intervention (2.4±0.3 to 3.1±0.3, p=0.01). Global microarray analysis profiling from whole blood was performed to examine changes in gene expression and to explore biological pathways that were significantly changed in response to the intervention. A total of 1,459 probes corresponding to mRNA transcripts (717 up, 742 down) were differentially expressed with a fold change≥1.2 and P<0.05. Among the genes identified were hexokinase 3 (HK3), ATPase, H+ transporting V0 subunit e2 (ATPV0E), and sterol regulatory element binding transcription factor 1 (SREBF1), and endothelial cell adhesion molecule (ESAM). There were 8 pathways identified that met the criteria for significance, including insulin signaling, type 1 diabetes, and glycerophospholipid metabolism. Participants that increased insulin sensitivity exhibited five times the number of significant genes altered compared to non-responders (1,144 vs. 230). These findings offer insight into the molecular mechanisms underlying health improvements among high-risk Latino youth. Lifestyle interventions may contribute to improved insulin sensitivity through pathways related to insulin signaling and immune response. Further, genetic factors may mediate response to lifestyle intervention.