Dataset Information

Bypassing hazard of housekeeping genes: their evaluation in rat granule neurons treated with cerebrospinal fluid of multiple sclerosis subjects.

ABSTRACT: Gene expression studies employing real-time PCR has become an intrinsic part of biomedical research. Appropriate normalization of target gene transcript(s) based on stably expressed housekeeping genes is crucial in individual experimental conditions to obtain accurate results. In multiple sclerosis (MS), several gene expression studies have been undertaken, however, the suitability of housekeeping genes to express stably in this disease is not yet explored. Recent research suggests that their expression level may vary under different experimental conditions. Hence it is indispensible to evaluate their expression stability to accurately normalize target gene transcripts. The present study aims to evaluate the expression stability of seven housekeeping genes in rat granule neurons treated with cerebrospinal fluid of MS patients. The selected reference genes were quantified by real time PCR and their expression stability was assessed using GeNorm and NormFinder algorithms. GeNorm identified transferrin receptor (Tfrc) and microglobulin beta-2 (B2m) the most stable genes followed by ribosomal protein L19 (Rpl19) whereas ?-actin (ActB) and glyceraldehyde-3-phosphate-dehydrogenase (Gapdh) the most fluctuated ones in these neurons. NormFinder identified Tfrc as the best invariable gene followed by B2m and Rpl19. ActB and Gapdh were the least stable genes as analyzed by NormFinder algorithm. Both methods reported Tfrc and B2m the most stably expressed genes and Gapdh the least stable one. Altogether our data demonstrate the significance of pre-validation of housekeeping genes for accurate normalization and indicates Tfrc and B2m as best endogenous controls in MS. ActB and Gapdh are not recommended in gene expression studies related to current one.

SUBMITTER: Mathur D

PROVIDER: S-EPMC4585208 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Bypassing hazard of housekeeping genes: their evaluation in rat granule neurons treated with cerebrospinal fluid of multiple sclerosis subjects.

Mathur Deepali D Urena-Peralta Juan R JR Lopez-Rodas Gerardo G Casanova Bonaventura B Coret-Ferrer Francisco F Burgal-Marti Maria M

Frontiers in cellular neuroscience 20150923

Gene expression studies employing real-time PCR has become an intrinsic part of biomedical research. Appropriate normalization of target gene transcript(s) based on stably expressed housekeeping genes is crucial in individual experimental conditions to obtain accurate results. In multiple sclerosis (MS), several gene expression studies have been undertaken, however, the suitability of housekeeping genes to express stably in this disease is not yet explored. Recent research suggests that their ex ...[more]

PMID: 26441545

Similar Datasets

Project description:In relapsing-remitting multiple sclerosis (RRMS) subtype, the patient's brain itself is capable of repairing the damage, remyelinating the axon and recovering the neurological function. Cerebrospinal fluid (CSF) is in close proximity with brain parenchyma and contains a host of proteins and other molecules, which influence the cellular physiology, that may balance damage and repair of neurons and glial cells. The purpose of this study was to determine the pathophysiological mechanisms underpinning myelin repair in distinct clinical forms of MS and neuromyelitis optica (NMO) patients by studying the effect of diseased CSF on glucose metabolism and ATP synthesis. A cellular model with primary cultures of oligodendrocyte progenitor cells (OPCs) from rat cerebrum was employed, and cells were treated with CSF from distinct clinical forms of MS, NMO patients and neurological controls. Prior to comprehending mechanisms underlying myelin repair, we determine the best stably expressed reference genes in our experimental condition to accurately normalize our target mRNA transcripts. The GeNorm and NormFinder algorithms showed that mitochondrial ribosomal protein (Mrpl19), hypoxanthine guanine phosphoribosyl transferase (Hprt), microglobulin ?2 (B2m), and transferrin receptor (Tfrc) were identified as the best reference genes in OPCs treated with MS subjects and were used for normalizing gene transcripts. The main findings on microarray gene expression profiling analysis on CSF treated OPCs cells revealed a disturbed carbohydrate metabolism and ATP synthesis in MS and NMO derived CSF treated OPCs. In addition, using STRING program, we investigate whether gene-gene interaction affected the whole network in our experimental conditions. Our findings revealed downregulated expression of genes involved in carbohydrate metabolism, and that glucose metabolism impairment and reduced ATP availability for cellular damage repair clearly differentiate more benign forms from the most aggressive forms and worst prognosis in MS patients.

Project description:In a large multicentre sample of cognitively normal subjects, as a function of age, gender and APOE genotype, we studied the frequency of abnormal cerebrospinal fluid levels of Alzheimer's disease biomarkers including: total tau, phosphorylated tau and amyloid-β1-42. Fifteen cohorts from 12 different centres with either enzyme-linked immunosorbent assays or Luminex® measurements were selected for this study. Each centre sent nine new cerebrospinal fluid aliquots that were used to measure total tau, phosphorylated tau and amyloid-β1-42 in the Gothenburg laboratory. Seven centres showed a high correlation with the new Gothenburg measurements; therefore, 10 cohorts from these centres are included in the analyses here (1233 healthy control subjects, 40-84 years old). Amyloid-β amyloid status (negative or positive) and neurodegeneration status (negative or positive) was established based on the pathological cerebrospinal fluid Alzheimer's disease cut-off values for cerebrospinal fluid amyloid-β1-42 and total tau, respectively. While gender did not affect these biomarker values, APOE genotype modified the age-associated changes in cerebrospinal fluid biomarkers such that APOE ε4 carriers showed stronger age-related changes in cerebrospinal fluid phosphorylated tau, total tau and amyloid-β1-42 values and APOE ε2 carriers showed the opposite effect. At 40 years of age, 76% of the subjects were classified as amyloid negative, neurodegeneration negative and their frequency decreased to 32% at 85 years. The amyloid-positive neurodegeneration-negative group remained stable. The amyloid-negative neurodegeneration-positive group frequency increased slowly from 1% at 44 years to 16% at 85 years, but its frequency was not affected by APOE genotype. The amyloid-positive neurodegeneration-positive frequency increased from 1% at 53 years to 28% at 85 years. Abnormally low cerebrospinal fluid amyloid-β1-42 levels were already frequent in midlife and APOE genotype strongly affects the levels of cerebrospinal fluid amyloid-β1-42, phosphorylated tau and total tau across the lifespan without influencing the frequency of subjects with suspected non-amyloid pathology.

Project description:The present study used comparative proteomic analysis of cerebrospinal fluid (CSF) in amyotrophic lateral sclerosis (ALS) patients in order to identify proteins that may act as diagnostic biomarkers and indicators of the pathogenesis of ALS. This analysis was performed using isobaric tags for relative and absolute quantitation (iTRAQ) technology, coupled with 2-dimensional liquid chromatography/mass spectrometry. Database for Annotation, Visualization and Integrated Discovery software was utilized for bioinformatic analysis of the data. Following this, western blotting was performed in order to examine the expression of 3 candidate proteins in ALS patients compared with healthy individuals [as a normal control (NC) group] or patients with other neurological disease (OND); these proteins were insulin-like growth factor II (IGF-2), glutamate receptor 4 (GRIA4) and leucine-rich α-2-glycoprotein 1 (LRG1). Clinical data, including gender, age, disease duration and ALS functional rating scale (ALSFRS-R) score, were also collected in the ALS patients. Multiple linear regression analysis was performed between the clinical data and the results of western blot analysis. A total of 248 distinct proteins were identified in the ALS and NC groups, amongst which a significant difference could be identified in 35 proteins; of these, 21 proteins were downregulated and 14 were upregulated. These differentially-expressed proteins were thus revealed to be associated with ALS. The western blot analysis confirmed a proportion of the data attained in the iTRAQ analysis, revealing the differential protein expression of IGF-2 and GRIA4 between the ALS and NC groups. IGF-2 was significantly downregulated in ALS patients (P=0.017) and GRIA4 was significantly upregulated (P=0.016). These results were subsequently validated in the 35-patient ALS and OND groups (P=0.002), but no significant difference was identified in LRG1 expression between these groups. GRIA4 protein expression was higher in male than female patients and was positively correlated with the ALSFRS-R score, meaning that GRIA4 expression was negatively correlated with the severity of ALS, while IGF-2 and LRG1 expression did not correlate with any clinical data. The present study thus demonstrated that GRIA4 expression levels, as a marker of severity, may be used as a reference for the timing of treatment, and that IGF-2 may serve as an effective biomarker of ALS progression.

Dataset Information

Bypassing hazard of housekeeping genes: their evaluation in rat granule neurons treated with cerebrospinal fluid of multiple sclerosis subjects.

Publications

Bypassing hazard of housekeeping genes: their evaluation in rat granule neurons treated with cerebrospinal fluid of multiple sclerosis subjects.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets