Iron induces insulin resistance in cardiomyocytes via regulation of oxidative stress

York University Librarie

approaches to discover the functional impact of non-synonymous single nucleotide polymorphisms in selective sweep regions of the Landrace genome

Objective The aim of this study was to discover the functional impact of non-synonymous single nucleotide polymorphisms (nsSNPs) that were found in selective sweep regions of the Landrace genome Methods Whole-genome re-sequencing data were obtained from 40 pigs, including 14 Landrace, 16 Yorkshire, and 10 wild boars, which were generated with the Illumina HiSeq 2000 platform. The nsSNPs in the selective sweep regions of the Landrace genome were identified, and the impacts of these variations on protein function were predicted to reveal their potential association with traits of the Landrace breed, such as reproductive capacity. Results Total of 53,998 nsSNPs in the mapped regions of pigs were identified, and among them, 345 nsSNPs were found in the selective sweep regions of the Landrace genome which were reported previously. The genes featuring these nsSNPs fell into various functional categories, such as reproductive capacity or growth and development during the perinatal period. The impacts of amino acid sequence changes by nsSNPs on protein function were predicted using two in silico SNP prediction algorithms, i.e., sorting intolerant from tolerant and polymorphism phenotyping v2, to reveal their potential roles in biological processes that might be associated with the reproductive capacity of the Landrace breed. Conclusion The findings elucidated the domestication history of the Landrace breed and illustrated how Landrace domestication led to patterns of genetic variation related to superior reproductive capacity. Our novel findings will help understand the process of Landrace domestication at the genome level and provide SNPs that are informative for breeding

Improved hematopoietic differentiation of human pluripotent stem cells via estrogen receptor signaling pathway

Additional file 2: Table S1. Temporal changes (%) of ER-Îą and hematopoietic phenotypes during hiPSC-derived hematopoietic differentiation

Acute perimyocarditis mimicking acute myocardial infarction in a 12-year-old boy with Duchenne muscular dystrophy

Differential diagnosis of chest pain in the pediatric population is important but can be challenging. A 12-year-old boy with Duchenne muscular dystrophy presented with chest pain, cardiac enzyme elevation, and convex ST elevations in the inferior leads with reciprocal ST depression in the anterior leads on electrocardiogram. Echocardiography on admission revealed normal left ventricular function. Suspecting acute myocardial infarction, we performed invasive coronary angiography, which revealed normal coronary arteries. A follow-up electrocardiogram showed an acute pericarditis pattern with concave ST elevations in most leads and PR depression, and follow-up echocardiography revealed global left ventricular dysfunction, suggestive of acute perimyocarditis. Ibuprofen was administered for acute pericarditis, and a continuous milrinone infusion was commenced for myocardial dysfunction. The chest pain improved by the next day, and the ST segment elevations normalized on day 4. Echocardiography on day 9 revealed improved left ventricular function. The patient was discharged on day 11, and he is doing well without chest pain through 12 months of follow-up. The last electrocardiogram showed normal sinus rhythm without ST change. Differential diagnosis of acute myocardial infarction and acute perimyocarditis is important for proper treatment strategies and the different prognoses of these two conditions

Variability of Response Time as a Predictor of Methylphenidate Treatment Response in Korean Children with Attention Deficit Hyperactivity Disorder

PURPOSE: Methylphenidate (MPH) is an effective medication for the treatment of attention deficit hyperactivity disorder (ADHD). However, about 30% of patients do not respond to or are unable to tolerate MPH. Based on previous findings, we hypothesized that great variability in response time (RT) among Korean children with ADHD on a computerized continuous performance attention test would be related to poor MPH treatment response. MATERIALS AND METHODS: Children (ages 6-18 years) with ADHD were recruited for a prospective 12-week, open-labeled, multicenter study to examine optimal dosage of OROS methylphenidate. Of the 144 subjects selected, 28 dropped out due to adverse events, medication noncompliance, or follow-up loss, and an additional 26 subjects with comorbid disorders were excluded from statistical analyses. We defined 'responders' as subjects who received a score of less than 18 on the attention deficit hyperactivity disorder rating scale (ARS; Korean version, K-ARS) and a score of 1 or 2 on the Clinical Global Impression-Improvement scale (CGI-I). RT variability was assessed with the ADHD diagnostic system (ADS). RESULTS: Fifty-nine (67%) subjects responded to MPH treatment. The non-responders showed greater RT variability at baseline (Mann Whitney U = 577.0, p < 0.01). Baseline RT variability was a significant predictor of MPH response (Nagelkerke R(2) = 0.136, p < 0.01). It predicted 94.9% of responder, 17.2% of non-responder and 69.3% of overall group. CONCLUSION: High RT variability may predict poor response to MPH treatment in children with ADHDope

A microRNA cluster in the Fragile-X region expressed during spermatogenesis targets FMR1.

Testis-expressed X-linked genes typically evolve rapidly. Here, we report on a testis-expressed X-linked microRNA (miRNA) cluster that despite rapid alterations in sequence has retained its position in the Fragile-X region of the X chromosome in placental mammals. Surprisingly, the miRNAs encoded by this cluster (Fx-mir) have a predilection for targeting the immediately adjacent gene, Fmr1, an unexpected finding given that miRNAs usually act in trans, not in cis Robust repression of Fmr1 is conferred by combinations of Fx-mir miRNAs induced in Sertoli cells (SCs) during postnatal development when they terminate proliferation. Physiological significance is suggested by the finding that FMRP, the protein product of Fmr1, is downregulated when Fx-mir miRNAs are induced, and that FMRP loss causes SC hyperproliferation and spermatogenic defects. Fx-mir miRNAs not only regulate the expression of FMRP, but also regulate the expression of eIF4E and CYFIP1, which together with FMRP form a translational regulatory complex. Our results support a model in which Fx-mir family members act cooperatively to regulate the translation of batteries of mRNAs in a developmentally regulated manner in SCs

Genome analysis of Yucatan miniature pigs to assess their potential as biomedical model animals

Objective Pigs share many physiological, anatomical and genomic similarities with humans, which make them suitable models for biomedical researches. Understanding the genetic status of Yucatan miniature pigs (YMPs) and their association with human diseases will help to assess their potential as biomedical model animals. This study was performed to identify non-synonymous single nucleotide polymorphisms (nsSNPs) in selective sweep regions of the genome of YMPs and present the genetic nsSNP distributions that are potentially associated with disease occurrence in humans. Methods nsSNPs in whole genome resequencing data from 12 YMPs were identified and annotated to predict their possible effects on protein function. Sorting intolerant from tolerant (SIFT) and polymorphism phenotyping v2 analyses were used, and gene ontology (GO) network and Kyoto encyclopedia of genes and genomes (KEGG) pathway analyses were performed. Results The results showed that 8,462 genes, encompassing 72,067 nsSNPs were identified, and 118 nsSNPs in 46 genes were predicted as deleterious. GO network analysis classified 13 genes into 5 GO terms (p<0.05) that were associated with kidney development and metabolic processes. Seven genes encompassing nsSNPs were classified into the term associated with Alzheimer’s disease by referencing the genetic association database. The KEGG pathway analysis identified only one significantly enriched pathway (p<0.05), hsa04080: Neuroactive ligand-receptor interaction, among the transcripts. Conclusion The number of deleterious nsSNPs in YMPs was identified and then these variants-containing genes in YMPs data were adopted as the putative human diseases-related genes. The results revealed that many genes encompassing nsSNPs in YMPs were related to the various human genes which are potentially associated with kidney development and metabolic processes as well as human disease occurrence

Preclinical evaluation of injectable sirolimus formulated with polymeric nanoparticle for cancer therapy

Nanoparticles are useful delivery vehicles for promising drug candidates that face obstacles for clinical applicability. Sirolimus, an inhibitor of mammalian target of rapamycin has gained attention for targeted anticancer therapy, but its clinical application has been limited by its poor solubility. This study was designed to enhance the feasibility of sirolimus for human cancer treatment. Polymeric nanoparticle (PNP)–sirolimus was developed as an injectable formulation and has been characterized by transmission electron microscopy and dynamic light scattering. Pharmacokinetic analysis revealed that PNP–sirolimus has prolonged circulation in the blood. In addition, PNP–sirolimus preserved the in vitro killing effect of free sirolimus against cancer cells, and intravenous administration displayed its potent in vivo anticancer efficacy in xenograft tumor mice. In addition, PNP–sirolimus enhanced the radiotherapeutic efficacy of sirolimus both in vitro and in vivo. Clinical application of PNP–sirolimus is a promising strategy for human cancer treatment

Proximity-Directed Labeling Reveals a New Rapamycin-Induced Heterodimer of FKBP25 and FRB in Live Cells

Mammalian target of rapamycin (mTOR) signaling is a core pathway in cellular metabolism, and control of the mTOR pathway by rapamycin shows potential for the treatment of metabolic diseases. In this study, we employed a new proximity biotin-labeling method using promiscuous biotin ligase (pBirA) to identify unknown elements in the rapamycin-induced interactome on the FK506-rapamycin binding (FRB) domain in living cells. FKBP25 showed the strongest biotin labeling by FRB-pBirA in the presence of rapamycin. Immunoprecipitation and immunofluorescence experiments confirmed that endogenous FKBP25 has a rapamycin-induced physical interaction with the FRB domain. Furthermore, the crystal structure of the ternary complex of FRB-rapamycin-FKBP25 was determined at 1.67-angstrom resolution. In this crystal structure we found that the conformational changes of FRB generate a hole where there is a methionine-rich space, and covalent metalloid coordination was observed at C2085 of FRB located at the bottom of the hole. Our results imply that FKBP25 might have a unique physiological role related to metallomics in mTOR signaling.ope