beta-sitosterol decreases irradiation-induced thymocyte early damage by regulation of the intracellular redox balance and maintenance of mitochondrial membrane stability

Both radiation injury and oxidation toxicity occur when cells are exposed to ion irradiation (IR), ultimately leading to apoptosis. This study was designed to determine the effect of beta-sitosterol (BSS) on early cellular damage in irradiated thymocytes and a possible mechanism of effect on irradiation-mediated activation of the apoptotic pathways. Thymocytes were irradiated (6 Gy) with or without BSS. Cell apoptosis and apoptosis-related proteins were evaluated. BSS decreased irradiation-induced cell death and nuclear DNA strand breaks while attenuating intracellular reactive oxygen species (ROS) and increasing the activities of antioxidant enzymes, including superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx). BSS decreased the release of cytochrome c from mitochondria to the cytosol and the mitochondrio-nuclear translocation of apoptosis-inducing factor (AIF). Furthermore, BSS partially inhibited the radiation-induced increase of cleaved caspase 3 and cleaved PARP, and attenuated the activation of JNK and AP-1. In addition, evidence suggests that ROS generated by irradiation are involved in this course of cell damage. The results indicate that BSS confers a radioprotective effect on thymocytes by regulation of the intracellular redox balance which is carried out via the scavenging of ROS and maintenance of mitochondrial membrane stability.     

Actin deficiency induces cofilin phosphorylation: proteome analysis of HeLa cells after beta-actin gene silencing

Actin-binding proteins regulate the dynamic structure and function of actin filaments in the cell. Much is known about how manipulation of the actin-binding proteins affects the structure and function of actin filaments; however, little is known about how manipulation of actin in the cell affects actin-binding proteins. We addressed this question by utilizing two technologies: RNA interference and 2-dimensional gel electrophoresis. We knocked down beta-actin expression in HeLa cells using short interfering RNA and applied 2-DGE to examine alterations in the HeLa cell proteome. We revealed a 2-5 fold increases of four protein spots on 2-D gels and identified these proteins by mass spectrometry. Three of the four proteins were actin-binding proteins, including cofilin, which promotes both disassembly and assembly of actin filaments but becomes inactivated when phosphorylated. Further examination revealed that the cofilin total protein level barely increased, but the phosphorylated cofilin level increased dramatically in HeLa cells after beta-actin siRNA treatment. These results suggest that in response to siRNA-induced beta-actin deficiency HeLa cells inactivate cofilin by phosphorylation rather than down-regulate its protein expression level. This study also demonstrates that the combination of RNA interference and 2-dimensional gel electrophoresis technologies provides a valuable method to study protein interactions in a specific cellular pathway.     

hORFeome v3.1: a resource of human open reading frames representing over 10,000 human genes

Complete sets of cloned protein-encoding open reading frames (ORFs), or ORFeomes, are essential tools for large-scale proteomics and systems biology studies. Here we describe human ORFeome version 3.1 (hORFeome v3.1), currently the largest publicly available resource of full-length human ORFs (available at ). Generated by Gateway recombinational cloning, this collection contains 12,212 ORFs, representing 10,214 human genes, and corresponds to a 51% expansion of the original hORFeome v1.1. An online human ORFeome database, hORFDB, was built and serves as the central repository for all cloned human ORFs (http://horfdb.dfci.harvard.edu). This expansion of the original ORFeome resource greatly increases the potential experimental search space for large-scale proteomics studies, which will lead to the generation of more comprehensive datasets.     

Air-pollutant chemicals and oxidized lipids exhibit genome-wide synergistic effects on endothelial cells

Background  

Ambient air pollution is associated with increased cardiovascular morbidity and mortality. We have found that exposure to ambient ultrafine particulate matter, highly enriched in redox cycling organic chemicals, promotes atherosclerosis in mice. We hypothesize that these pro-oxidative chemicals could synergize with oxidized lipid components generated in low-density lipoprotein particles to enhance vascular inflammation and atherosclerosis.     

The impact of infliximab treatment on quality of life in patients with inflammatory rheumatic diseases

In this study, we compare the health-related quality of life (HRQoL) of patients with moderate-to-severe rheumatoid arthritis (RA), psoriatic arthritis (PsA), and ankylosing spondylitis (AS), and study the effect of treatment with infliximab on the HRQoL of patients with these diseases. Short Form Health Survey-36 (SF-36) data from the placebo-controlled phases of 4 studies of infliximab in patients with inflammatory rheumatic diseases (n = 1990) were evaluated. Data came from the Anti-TNF Trial in Rheumatoid Arthritis with Concomitant Therapy (ATTRACT) (n = 428), the Safety Trial for Rheumatoid Arthritis with REMICADE Therapy (START) (n = 1083), the Ankylosing Spondylitis Study for the Evaluation of Recombinant Infliximab Therapy (ASSERT) (n = 279), and the Infliximab Multinational Psoriatic Arthritis Clinical Trial II (IMPACT II) (n = 200). SF-36 assessments were made at weeks 0, 10, 30, and 54 in ATTRACT, weeks 0, 6, and 22 in START, weeks 0, 12, and 24 in ASSERT, and weeks 0 and 14 in IMPACT II. All patient populations had significantly impaired physical aspects of HRQoL at baseline relative to the general population of the United States, and the magnitude of impairment was similar across the diseases. Mean baseline physical component summary scores were 29 in the RA cohort, 32 in the PsA cohort, and 29 in the AS cohort. In all 3 diseases, patients who received infliximab showed significant improvement in physical component summary scores compared with those who received placebo. The magnitude of the difference of improvement (effect size, 95%CI) between infliximab and placebo groups was similar in the AS (10.1, 9.2–11.0), PsA (8.6, 7.8–9.4), and RA (10.1, 9.2–11.0) cohorts. Patients with RA and those with PsA treated with infliximab also showed greater improvement in the mental component summary score than those in the placebo group with an effect size of 4.6 (4.2–5.1) in RA and 2.7 (2.4–3.1) in PsA. Patients in large randomized controlled studies of infliximab in RA, PsA, and AS had similar impairment in physical aspects of HRQoL at baseline and showed significantly greater improvement in HRQoL after treatment with infliximab.     

iTRAQ-coupled 2D LC-MS/MS analysis on protein profile in vascular smooth muscle cells incubated with S- and R-enantiomers of propranolol: possible role of metabolic enzymes involved in cellular anabolism and antioxidant activity

Propranolol is a nonselective beta-blocker of the beta-adrenergic receptors, and the S-enantiomer is more active compared with the R-enantiomer. Clinically, it has been shown to be effective in hypermetabolic burn patients by decreasing cardiac work, protein catabolism, and lipolysis. While gene expression profiles have recently been reported in children receiving propranolol treatment, variations from one individual to another may have influenced the data analysis. Using iTRAQ-coupled 2D LC-MS/MS analysis, we report here the first study of protein profile in vascular smooth muscle cells incubated separately with the two enantiomers of propranolol. Four types of cellular proteins including metabolic enzymes, signaling molecules, cytoskeletal proteins, and those involved in DNA synthesis/protein translation displayed changes. The higher protein level of a number of enzymes involved in cellular anabolism and antioxidant activity in cells incubated with the S-enantiomer, as revealed by LC-MS/MS, was further supported by real-time PCR and Western blot analyses. Significantly, the increase in the anabolic activity associated with the higher level of metabolic enzymes was also supported by the higher intracellular concentration of the metabolic cofactor NAD+ which was a result of an increased oxidation of NADH. Our findings therefore provide molecular evidence on metabolic effect associated with propranolol treatment. The metabolic enzymes identified in our study may in turn be useful targets for future pharmaceutical interventions to reduce clinical side effects following propranolol treatment.     

Development of molecular markers based on CRa gene sequencing of different clubroot disease-resistant cultivars of Chinese cabbage

Background

CRa is a key gene in Chinese cabbage (Brassica rapa ssp. pekinensis) that confers resistance to Plasmodiophora brassicae. In order to efficiently screen the clubroot resistance (CR) gene CRa in breeding, two functional codominant markers of the CRa gene were developed.

Methods and results

In this study, through comparing the CRa allele sequences in resistant and susceptible cultivars of Chinese cabbage, we found two insertion and deletion of sequence variations in the fourth exon between resistant and susceptible cultivars. Two functional codominant markers for CRa gene were obtained based on the variations, namely, CRaEX04-1 and CRaEX04-3. The lengths of the extended fragment of CRaEX04-1 marker were 321 bp and 186 bp in resistant and susceptible cultivars, respectively. In contrast, those of CRaEX04-3 were 704 bp and 413 bp, respectively. We verified the genetic stability between the developed markers and CRa gene using 57 Chinese cabbage cultivars with known resistance and two genetic populations. The results showed that the marker identification was completely consistent with the known phenotypes in 57 cultivars. The marker identification results followed the 3:1 of Mendel’s first law in the F₂ population, and the 1:1 of Mendel’s first law in the BC₁.

Conclusions

CRaEX04-1 and CRaEX04-3 can be used as a practical molecular marker for breeding and germplasm resource creation of clubroot disease-resistant Chinese cabbage.