Optimizing separation efficiency of 2-DE procedures for visualization of different superoxide dismutase forms in a cellular model of amyotrophic lateral sclerosis.

Neurodegenerative diseases such as Alzheimer disease (AD) and Parkinson disease (PD) have been associated with increased production of reactive oxygen species. In AD and PD patients, superoxide dismutase (SOD1) was also indicated as a major target of oxidative damage. In particular, in brain tissue of these patients, different SOD1 isoforms have been identified, although their functional role still remains to be elucidated. In the light of the possibility that different SOD1 entities could be expressed also in other neurodegenerative disorders, as a sort of unifying event with AD and PD, we have investigated amyotrophic lateral sclerosis (ALS) using human neuroblastoma SH-SY5Y cells with mutated SOD1 gene H46R as cellular model. 2-DE using a narrow-range IPG 4–7 strips in the first dimension and linear 15% SDS-PAGE in the second allowed to separate different SOD1 spots. MALDI-TOF MS and CapLC-MS/MS have been used for their complete identification. This is the first report in which the presence of SOD1 (iso)forms in a cellular model of ALS has been evidenced

Optimizing separation efficiency of 2-DE procedures for visualization of different superoxide dismutase forms in a cellular model of amyotrophic lateral sclerosis

Neurodegenerative diseases such as Alzheimer disease (AD) and Parkinson disease (PD) have been associated with increased production of reactive oxygen species. In AD and PD patients, superoxide dismutase (SOD1) was also indicated as a major target of oxidative damage. In particular, in brain tissue of these patients, different SOD1 isoforms have been identified, although their functional role still remains to be elucidated. In the light of the possibility that different SOD1 entities could be expressed also in other neurodegenerative disorders, as a sort of unifying event with AD and PD, we have investigated amyotrophic lateral sclerosis (ALS) using human neuroblastoma SH-SY5Y cells with mutated SOD1 gene H46R as cellular model. 2-DE using a narrow-range IPG 4–7 strips in the first dimension and linear 15% SDS-PAGE in the second allowed to separate different SOD1 spots. MALDI-TOF MS and CapLC-MS/MS have been used for their complete identification. This is the first report in which the presence of SOD1 (iso)forms in a cellular model of ALS has been evidenced

GC-MS Based Plasma Metabolomics for Identification of Candidate Biomarkers for Hepatocellular Carcinoma in Egyptian Cohort.

This study evaluates changes in metabolite levels in hepatocellular carcinoma (HCC) cases vs. patients with liver cirrhosis by analysis of human blood plasma using gas chromatography coupled with mass spectrometry (GC-MS). Untargeted metabolomic analysis of plasma samples from participants recruited in Egypt was performed using two GC-MS platforms: a GC coupled to single quadruple mass spectrometer (GC-qMS) and a GC coupled to a time-of-flight mass spectrometer (GC-TOFMS). Analytes that showed statistically significant changes in ion intensities were selected using ANOVA models. These analytes and other candidates selected from related studies were further evaluated by targeted analysis in plasma samples from the same participants as in the untargeted metabolomic analysis. The targeted analysis was performed using the GC-qMS in selected ion monitoring (SIM) mode. The method confirmed significant changes in the levels of glutamic acid, citric acid, lactic acid, valine, isoleucine, leucine, alpha tocopherol, cholesterol, and sorbose in HCC cases vs. patients with liver cirrhosis. Specifically, our findings indicate up-regulation of metabolites involved in branched-chain amino acid (BCAA) metabolism. Although BCAAs are increasingly used as a treatment for cancer cachexia, others have shown that BCAA supplementation caused significant enhancement of tumor growth via activation of mTOR/AKT pathway, which is consistent with our results that BCAAs are up-regulated in HCC

Workflow of our GC-MS based untargeted metabolomic and targeted analyses for biomarker discovery.

<p>The number of candidate metabolites analyzed at specific steps is shown in parenthesis.</p

Example of a retrieved EIC for valine.

<p>The inset in the top left shows the expected ratios for the fragments based on the library to guide the visual inspection. The doted vertical lines show the expected and estimated elution time of the analyte. Although, the background signal of 73 from other compounds is reflected in the apex score, its impact on the AUC is diminished by baseline correction.</p

Metabolites with significant changes in their levels in HCC vs. cirrhosis based on targeted analysis of plasma by GC-SIM-MS.

<p>The metabolites in the top two panels show increasing trend with the progression of HCC. The metabolites in the bottom panel are down-regulated in HCC vs. cirrhosis. While lactic acid and citric acid show decreasing trend with the progression of HCC, sorbose is down-regulated overall in HCC vs. cirrhosis.</p