Metabolic Syndrome and Its Components Predict the Risk of Type 2 Diabetes Mellitus in the Mainland Chinese: A 3-Year Cohort Study.

INTRODUCTION: It has well established that metabolic syndrome (MetS) can predict the risk of type 2 diabetes mellitus (T2DM) in some population groups. However, limited evidence is available regarding the predictive effect of MetS for incident T2DM in mainland Chinese population. METHODS: A 3-year cohort study was performed for 9735 Chinese without diabetes at baseline. MetS and its components were assessed by multivariable analysis using Cox regression. Prediction models were developed. Discrimination was assessed with area under the receiver operating characteristic curves (AUCs), and performance was assessed by a calibration curve. RESULTS: The 3-year cumulative incidence of T2DM was 11.29%. Baseline MetS was associated with an increased risk of T2DM after adjusting for age (HR = 2.68, 95% CI, 2.27-3.17 in males; HR = 2.59, 95% CI, 1.83-3.65 in females). Baseline MetS exhibited relatively high specificity (88% in males, 94% in females) and high negative predictive value (90% in males, 94% in females) but low sensitivity (36% in males, 23% in females) and low positive predictive value (31% in males and females) for predicting the 3-year risk of T2DM. AUCs, including age and components of MetS, for the prediction model were 0.779 (95% CI: 0.759-0.799) in males and 0.860 (95% CI: 0.836-0.883) in females. Calibration curves revealed good agreement between prediction and observation results in males; however, the model could overestimate the risk when the predicted probability is >40% in females. CONCLUSIONS: MetS predicts the risk of T2DM. The quantitative MetS-based prediction model for T2DM risk may improve preventive strategies for T2DM and present considerable public health benefits for the people in mainland China.

The efficacy advantage of evolocumab (AMG 145) dosed at 140mg every 2weeks versus 420mg every 4weeks in patients with hypercholesterolemia: Evidence from a meta-analysis.

BACKGROUND: Evolocumab (AMG 145), a PCSK9 inhibitor, has been shown to decrease low-density lipoprotein cholesterol (LDL-C) levels. Doses of 140mg administered every 2weeks (Q2W) and 420mg administered every 4weeks (Q4W) are widely used, and both dosing schedules were effective in clinical trials. However, some researchers have speculated that 140mg Q2W administration has equal or even greater efficacy. This meta-analysis was performed to assess the differences in efficacy and safety between the two doses. METHODS: We searched the PubMed, EMBASE, and Web of Science databases to identify relevant clinical trials published before January 2016. A total of 2403 patients from 8 randomized controlled trials were identified and included in the analysis. RESULTS: Evolocumab administered at 140mg Q2W resulted in a greater percent change from baseline in LDL-C concentration (-7.27; 95% confidence interval (CI), -10.36 to -4.18) and had greater efficacy in achieving the treatment goal of LDL-C ≤1.8mmol/L with an relative risk (RR) of 1.09 (95% CI, 1.00 to 1.18) compared with 420mg Q4W in patients who were concomitantly treated with statins. These findings were not significantly different between the 140mg Q2W and 420mg Q4W groups when evolocumab was administered as monotherapy. There was no difference in the rate of occurrence of the main treatment-related adverse events between the two doses. CONCLUSIONS: Evolocumab administered at 140mg Q2W was more effective than the 420mg Q4W dosage at lowering lipid concentrations, especially in patients who concomitantly received stable statin therapy.

Prostate volume growth rate changes over time: Results from men 18 to 92 years old in a longitudinal community-based study.

Previous investigations have shown that changes in total prostate volume (TPV) are highly variable among aging men, and a considerable proportion of aging men have a stable or decreasing prostate size. Although there is an abundance of literature describing prostatic enlargement in association with benign prostatic hyperplasia, less is known about the appropriate age cut-off points for TPV growth rate. In this community-based cohort study, TPV was examined once a year in men who had consecutive health checkup, during a follow-up of 4 years. A total of 5058 men (age 18-92 years old) were included. We applied multiple regression analyses to estimate the correlation between TPV growth rate and age. Overall, 3232 (63.9%) men had prostate growth, and 1826 (36.1%) had a stable or decreased TPV during the study period. The TPV growth rate was correlated negatively with baseline TPV (r=-0.32, P<0.001). Among 2620 men with baseline TPV <15 cm3, the TPV growth rate increased with age (ß=0.98, 95% CI: 0.77%-1.18%) only up to 53 years old. Among 2188 men with baseline TPV of 15-33.6 cm3, the TPV growth rate increased with age (ß=0.84, 95% CI, 0.66%-1.01%) only up to 61 years old after adjusting for factors of hypertension, obesity, baseline TPV, diabetes mellitus and dyslipidemia. In this longitudinal study, the TPV growth rate increased negatively with baseline TPV, only extending to a certain age and not beyond. Further research is needed to identify the mechanism underlying such differences in prostate growth.

Octacosanol enhances the proliferation and migration of human umbilical vein endothelial cells via activation of the PI3K/Akt and MAPK/Erk pathways.

Atherosclerosis is characterized by endothelial dysfunction, lipid deposition, fibro-proliferative reactions and inflammation. Octacosanol is a high-molecular-weight primary aliphatic alcohol. As the main component of a cholesterol-lowering drug, octacosanol could inhibit lipids accumulation and cholesterol metabolism. To explore the indication of octacosanol on endothelial protection, we evaluated its effects on the proliferation and migration of human umbilical vein endothelial cells (HUVEC). Cell viability assay using methyl thiazolyl tetrazolium and 5-ethynyl-2'-deoxyuridine revealed that 3.125 µg/ml octacosanol promoted the proliferation of HUVEC. A cell migration assay indicated that 0.781 and 3.125 µg/ml octacosanol increased the migration of HUVEC. Moreover, the phosphorylation levels of Akt and Erk1/2 were significantly elevated under exposure to octacosanol. Blocking the activation of Akt and Erk with their potent inhibitors LY294002 and PD98059, respectively, markedly attenuated the octacosanol-induced proliferation and migration of HUVEC. These findings demonstrated for the first time that octacosanol enhanced the proliferation and migration of HUVEC and mediated these effects through activation of the PI3K/Akt and MAPK/Erk1/2 signaling pathways.

Elevated serum levels of soluble Axl in acute coronary syndrome.

BACKGROUND: Morbidities related to atherosclerosis, such as acute coronary syndrome (ACS), remain the leading cause of mortality. Axl is a receptor tyrosine kinase that is expressed in mammalian vascular and immune cells. Axl signaling is involved in the regulation of the inflammatory response. A considerable amount of evidence indicates that inflammation is responsible for the development of atherosclerosis in patients with ACS. METHODS: To assess the relation of Axl and ACS, we recruited 64 patients with coronary heart disease: 34 with ACS, 30 with stable coronary heart disease, and 24 apparently healthy controls. Serum concentrations of soluble Axl (sAxl) were quantified by enzyme-linked immunosorbent assay. High-sensitivity C-reactive protein, tumor necrosis factor alpha, troponin I, and other routine biochemical markers were also measured. RESULTS: The levels of sAxl were significantly higher in patients with ACS than in the controls (P=0.005). Furthermore, correlation analysis indicated that sAxl was significantly associated with serum levels of high-sensitivity C-reactive protein (r=0.283, P=0.008), tumor necrosis factor alpha (r=0.565, P<0.001), and troponin I (r=0.264, P=0.013). Logistic regression analysis (odds ratio=1.038, 95% confidence interval, 1.008-1.069, P=0.012) indicated a significant association between sAxl and ACS. CONCLUSIONS: Serum levels of sAxl correlate to inflammatory biochemical markers. These findings demonstrate for the first time that sAxl does have a role in ACS, presumably connected to the inflammation.

Increased risk of cerebrovascular events in patients with cancer treated with bevacizumab: a meta-analysis.

Arterial ischemia and hemorrhage are associated with bevacizumab, an inhibitor of vascular endothelial growth factor that is widely used to treat many types of cancers. As specific types of arterial ischemia and hemorrhage, cerebrovascular events such as central nervous system (CNS) ischemic events and CNS hemorrhage are serious adverse events. However, increased cerebrovascular events have not been uniformly reported by previous studies. New randomized controlled trials (RCTs) have been reported in recent years and we therefore conducted an up-to-date meta-analysis of RCTs to fully characterize the risk of cerebrovascular events with bevacizumab. We searched the databases of PubMed, Web of Science, and the American Society of Clinical Oncology conferences to identify relevant clinical trials up to February 2014. Eligible studies included prospective RCTs that directly compared patients with cancer treated with and without bevacizumab. A total of 12,917 patients from 17 RCTs were included in our analysis. Patients treated with bevacizumab had a significantly increased risk of cerebrovascular events compared with patients treated with control medication, with a relative risk of 3.28 (95% CI, 1.97-5.48). The risks of CNS ischemic events and CNS hemorrhage were increased compared with control, with RRs of 3.22 (95% CI, 1.71-6.07) and 3.09 (95% CI, 1.36-6.99), respectively. Risk varied with the bevacizumab dose, with RRs of 3.97 (95% CI, 2.15-7.36) and 1.96 (95% CI, 0.76-5.06) at 5 and 2.5 mg/kg/week, respectively. Higher risks were observed in patients with metastatic colorectal cancer (RR, 6.42; 95% CI, 1.76-35.57), and no significant risk was observed in other types of tumors. In conclusion, the addition of bevacizumab significantly increased the risk of cerebrovascular events compared with controls, including CNS ischemic events and CNS hemorrhage. The risk may vary with bevacizumab dose and tumor type.

Growth arrest-specific gene 6 protein promotes the proliferation and migration of endothelial progenitor cells through the PI3K/AKT signaling pathway.

Endothelial progenitor cells (EPCs) play an important role in endothelial repair and vascular regeneration. Growth arrest-specific gene 6 (Gas6) is a novel key regulator of the vascular system, which is linked to a number of cardiovascular diseases. However, the effects of Gas6 on EPCs have not been elucidated to date. The present study was designed to determine the biological function of EPCs treated with Gas6 and to eludicate the underlying mechanisms. EPCs were isolated from umbilical cord blood and treated with various concentrations (25, 50, 100 and 200 ng/ml) of Gas6. The proliferation, migration and angiogenesis of the Gas6-treated EPCs were evaluated by MTT assay, Transwell assay and in vitro tube formation assay, respectively. The phosphorylation status of AKT and ERK was evaluated by western blot analysis. The results demonstrated that treatment with Gas6 enhanced the proliferation and migration of the EPCs in a dose-dependent manner. However, Gas6 did not promote the differentiation of EPCs on Matrigel. Gas6 induced the phosphorylation of AKT, but not that of ERK. The enhanced proliferation and migration induced by Gas6 was markedly suppressed by the inhibitor of PI3K but not by that of ERK. These results suggest that Gas6 activates the AKT signaling pathway, which, in turn, promotes the proliferation and migration of EPCs.

Angiogenesis inhibitor bevacizumab increases the risk of ischemic heart disease associated with chemotherapy: a meta-analysis.

Concerns have arisen regarding the risk of ischemic heart disease with the novel antiangiogenic agent bevacizumab, a recombinant humanised monoclonal antibody to the vascular endothelial growth factor that is widely used in cancer treatment. Currently, the role of bevacizumab in ischemic heart disease is controversial. This meta-analysis was therefore performed to assess the overall risk of ischemic heart disease associated with the use of bevacizumab. The databases of PubMed, EMBASE and Web of Science were searched for English language studies of randomised controlled trials comparing bevacizumab with control therapy published through October 25, 2012. Summary incidence rates, relative risks (RRs) and 95% confidence intervals (CIs) were calculated using random-effects or fixed-effects models based on the heterogeneity of the included studies. A total of 4,617 patients from 7 randomised controlled trials were identified and included for analysis. Among those patients receiving bevacizumab, the summary incidence of ischemic heart disease was 1.0% (95% CI, 0.6%-1.4%). Patients treated with bevacizumab had a significantly increased risk of ischemic heart disease with an RR of 2.49 (95% CI, 1.37-4.52) compared with controls. In addition, both high doses and low doses of bevacizumab increased the risk of cardiac ischemia (low dose at 2.5 mg/kg per week: RR, 2.14 [95% CI, 1.09-4.19]; high dose at 5 mg/kg per week: RR, 4.81 [95% CI, 1.03-22.42]). Bevacizumab was also found to significantly increase the risk of cardiac ischemia in patients with colorectal cancer (RR, 2.13; 95% CI, 1.11-4.06) compared with controls. This meta-analysis shows the use of bevacizumab was associated with an increased risk of developing ischemic heart disease in colorectal cancer patients receiving this drug. Our conclusions are limited by the available data. Further evaluations of high-quality RCTs are needed.

[Role of ubiquitin ligase Ring2 in DNA damage induced by benzo[a]pyrene].

OBJECTIVE: To investigate the role of ubiquitin ligase Ring2 in the DNA damage induced by benzo[a]pyrene (B[a]P). METHODS: The expression of Ring2 in human bronchial epithelial (16HBE) cells was inhibited by small interfering RNA (siRNA) to obtain siRNA-Ring2 16HBE cells. The siRNA-Ring2 16HBE cells, as well as normal 16HBE cells, were exposed to B[a]P (0, 1, 2, 4, 8, 16, and 32 µmol/L) for 24 h; other siRNA-Ring2 16HBE cells and normal 16HBE cells were exposed to B [a]P (16 µmol/L) for 0, 1, 2, 4, 8, 12, and 24 h. The levels of DNA damage were evaluated by alkaline single cell gel electrophoresis assay. RESULTS: After being treated with siRNA for 36 h, the siRNA-Ring2 16HBE cells showed a 72% decrease in Ring2 expression compared with normal 16HBE cells. The analysis of covariance showed that whether to be treated with siRNA and concentration of B[a]P had impacts on Olive tail moment (OTM) (P = 0.032 and P < 0.001); the adjusted mean of OTM was significantly higher in siRNA-Ring2 16HBE cells than in normal 16HBE cells. Whether to be treated with siRNA and B[a]P exposure time had impacts on OTM (P = 0.031 and P < 0.001); the adjusted mean of OTM was significantly higher in siRNA-Ring2 16HBE cells than in normal 16HBE cells. CONCLUSION: The DNA of 16HBE cells with decreased Ring2 expression has increased susceptibility to B[a]P, which may be due to reduced H2A monoubiquitination following decrease in Ring2 expression.

Apolipoprotein a5 gene polymorphism and risk for metabolic syndrome: a meta-analysis.

BACKGROUND: Many studies have focused on the association between the apolipoprotein A5 (ApoA5) polymorphism and the risk of metabolic syndrome (MetS). However, these studies drew inconsistent conclusions. The aim of this study was to evaluate the exact association between the ApoA5 polymorphism and MetS in a large-scale meta-analysis. METHODS: The PubMed, Embase, and Science Citation Index (ISI Web of Science) databases were searched to collect all publications on the association between the ApoA5 polymorphism and MetS. Two common variants of ApoA5 (namely -1131T>C in the promoter region and c.56C>G in the coding region) with the risk of MetS were analyzed. The overall odd ratios (ORs) and 95% confidence intervals (CIs) for -1131T>C (CC+TC) versus TT genotype and c.C56G (GG+GC) versus CC were assessed between the MetS and control group. Subgroup analysis was further performed by ethnicity. The meta-analysis was performed by Stata11.0. RESULTS: Twelve studies from 10 publications were chosen in our meta-analysis. The combined results showed that C allele carriers (CC+TC) of -1131T>C had a significantly higher risk of MetS for the overall (OR=1.32; 95% CI: 1.14-1.53; p=0.000) with moderate heterogeneity (I2=54.9%, p=0.014). Subgroup analysis was further performed according to ethnicity, and the association was still significant in Asians (OR=1.42; 95% CI: 1.25-1.62; p=0.000), but not in white populations (OR=1.25; 95% CI: 0.97-1.61; p=0.087). When analyzing the association between c.C56G and MetS, the G allele carrier (GG+GC) genotype significantly increased the risk of MetS (OR=1.32; 95% CI: 1.15-1.50; p=0.000) in white populations. No significant publication bias was observed in either -1131T>C or c.C56G. CONCLUSIONS: Our study suggested that the ApoA5 -1131T>C polymorphism was significantly associated with the risk of MetS in Asians, but not in white populations. However, the c.C56G polymorphism was significantly associated with MetS in white populations.

Role of steric effects in protein-directed enediyne cycloaromatization of neocarzinostatin.

The antibiotic neocarzinostatin comprises a carrier protein with a well-defined cavity for accommodating an active enediyne chromophore. The protein has two disulfides, one (Cys(37)-Cys(47)) lies on the cavity bottom and the other (Cys(88)-Cys(93)) in a constrained short loop. When the chromophore is not bound to the protein, a thiol-induced cycloaromatization of the enediyne into a tetrahydroindacene derivative is responsible for the potent antitumor activity. When it is protein-bound, the protein diverts the cycloaromatization pathway to form a distinct hydroxyisochromene-type product. How the protein directs the enediyne chemistry is an interesting puzzle, and various suggestions have been proposed in the past. We screened more than fifty thiols and manipulated conditions to locate reaction features and search for factors that could influence the protein directing strength. Thiol- and oxygen-concentration-dependence studies suggested that disulfides, which maintain the steric rigidity of the protein, could play a key role in diverting the cycloaromatization pathway. For direct proofs, we made mutations at each of the two disulfides by replacing sulfur atoms with oxygen. Circular dichroism and two-dimensional NMR spectroscopy studies suggested that the mutations changed neither the protein conformation nor the ligand interactions. Analyses of the thiol-induced cycloaromatization revealed that rupture of Cys(37)-Cys(47) made the protein almost completely lose its chemical directing ability, whereas rupture of Cys(88)-Cys(93) had only a minor influence. The results demonstrated that the steric rigidity of the binding cavity, but not necessary the whole protein, played an important role in the protein-directed mechanism.

[Effect of necrostatin-1 on apoptosis induced by aluminum and its mechanism].

OBJECTIVE: To study the effect of necrostatin (Nec-1) on apoptosis induced by aluminum (Al), and approach the mechanism. METHODS: Neural cell death model was made by 4 mmol/L Al treated neuroblastoma cells (SH-SY5Y). Cell viabilities were detected at different concentrations of Al and/or Nec-1. Hoechst 33342/PI double staining was used to observe apoptosis and (or) necrosis that were quantified by flow cytometry using Annexin V/PI double staining. Apoptotic pathway was tested by activities of Caspase-3, Caspase-8 and Caspase-9. In addition, the expression of NF-kappa B and Cyt-c was measured by immunocytochemistry. RESULTS: Cell viabilities were significantly decreased with the increasing concentrations of Al (P < 0.05), which could be significantly upregulated by 60 micromol/L Nec-1 (P < 0.05) and were correlated with the concentrations of Nec-1 (P < 0.05, P < 0.01). Apoptosis and necrosis were observed under fluorescent microscope and quantified by flow cytometry, which suggested an increasing trend of apoptotic and necrotic rates (P < 0.05, P < 0.01). Whereas, Nec-1 could not only decrease the necrotic rate but also apoptotic rate as well (P < 0.05, P < 0.01). Data of Nec-1 on caspases activities showed that Nec-1 could not affect Caspase-9 activity (P > 0.05) and Cty-c protein expression as well (P > 0.05). However, Nec-1 could reduce Caspase-8 activity significantly (P < 0.05, P < 0.01) and increase NF-kappa B protein expression (P < 0.05, P < 0.01) and finally decrease Caspase-3 activity (P < 0.05). CONCLUSION: Nec-1 could reduce cell apoptosis induced by Al, through Caspase-8 pathway, and up-regulate the expression of NF-kappa B protein.

Trichlorfon induces apoptosis in SH-SY5Y neuroblastoma cells via the endoplasmic reticulum?

This study investigated the role of the endoplasmic reticulum pathway in apoptosis induced by trichlorfon in SH-SY5Y human neuroblastoma cells. Flow cytometric analysis demonstrated that trichlorfon and its degradation product dichlorvos-induced apoptosis in a dose-dependent manner and Hoechst 33342 staining experiments revealed trichlorfon/dichlorvos-induced nucleus condensation. Western blot analysis indicated decreased expression of caspase-12 and increased activated caspase-12 in trichlorfon-treated cells compared to a control, suggesting that trichlorfon may induce apoptosis in SH-SY5Y partly via the endoplasmic reticulum. Intracellular Ca(2+) level ([Ca(2+)](i)) in SH-SY5Y cells increased after treatment with trichlorfon but was significantly reduced by pre-treatment with a combination of a calcium channel blocker, an inositol trisphosphate receptor inhibitor, and a ryanodine receptor inhibitor. Percent apoptosis and activated caspase-3 and caspase-12 decreased in pre-treated cells compared to those treated with trichlorfon alone. Trichlorfon-induced apoptosis was also inhibited by the protein kinase C activator, phorbol 12-myristate 13-acetate (PMA). These results suggest that endoplasmic reticulum stress, which is related to calcium, may be involved in the cytotoxicity of trichlorfon.

[Role of necroptosis in aluminum induced SH-SY5Y cell death].

OBJECTIVE: To study whether necroptosis exists or not in neural cell death induced by aluminum. METHODS: SH-SY5Y cells were treated with 4 mmol/L AlCl(3) x 6H(2)O The cell viability was determined with CCK-8 kit after treated with Nec-1 at different dosages (0, 30, 60, 90 micromol/L). Mitochondria membrane potential (MMP), content of reactive oxygen species (ROS), and apoptotic rate/necrotic rates were measured with cytometry. RESULTS: Nec-1 ameliorated the necrotic-like cell morphology, the cell viability were 0.28 +/- 0.05, 0.58 +/- 0.03, 0.68 +/- 0.04, and 1.03 +/- 0.17, there were significant differences between the Nec-1 treated groups and that of controls (t values were 3.25, 3.36, 4.56; P < 0.05). After Nec-1 treatment, the necrotic rates were 16.46% +/- 0.54%, 10.40% +/- 0.64%, 5.43% +/- 0.68%, and 6.28% +/- 0.35%, there were significant differences between the Nec-1 treated cells and that of controls (t values were 3.62, 7.32, 6.96; P < 0.05); while the apoptotic rates were 8.68 +/- 0.36, 7.66 +/- 0.53, 5.68 +/- 0.41, and 4.13 +/- 0.41, there was no significant difference among the groups (F = 6.33, P = 0.11). Cytometry had shown the increased cell MMPs after Nec-1 treatment, which were 67.54 +/- 6.36, 49.42 +/- 5.96, 84.79 +/- 6.86, and 95.51 +/- 7.01, there were significant differences as comparing MMPs of the middle and high dosage of Nec-1 treated cells with those of controls (t values were 3.21, 4.01; P < 0.05); while ROS contents in the Nec-1 treated SH-SY5Y cells were 54.07 +/- 3.32, 52.79 +/- 2.36, 54.68 +/- 1.91, and 59.23 +/- 2.96, there was no significant difference among the groups (F = 5.26, P = 0.19). CONCLUSION: Nec-1, as a specific inhibitor of necroptosis, might effectively block the cell death pathway induced by aluminum, it indicates that necroptosis should be one of the major causes of the SH-SY5Y cell toxicity induced by aluminum, and necroptosis also plays an important role in aluminum induced SH-SY5Y cell death.

Plasma level of growth arrest-specific 6 (GAS6) protein and genetic variations in the GAS6 gene in patients with acute coronary syndrome.

Growth arrest-specific gene 6 (GAS6) encodes a vitamin K-dependent protein that regulates inflammation, angiogenesis, and atherosclerotic plaque formation. The level of GAS6 expression is associated with plaque stability and stroke. We explored the role of GAS6 in cardiovascular disease, particularly in acute coronary syndrome (ACS). We determined the plasma levels of GAS6 protein by using an enzyme-linked immunosorbent assay method and investigated the role of the single nucleotide polymorphism (c.834+7G>A) in ACS. The median (interquartile range) plasma GAS6 levels were 16.9 microg/L (13-28 microg/L) in healthy control subjects and 10.65 microg/L (5.7-27.5 microg/L) in patients with ACS. The genotype frequencies for GG, AG, and AA, respectively, in patients with ACS were 66% (37/56), 29% (16/56), and 5% (3/56) and were 35% (14/40), 45% (18/40), 20% (8/40) in the control group. The AA genotype and A allele were less frequent in patients with ACS than in control subjects (P < .001). Our study indicates that GAS6 plasma concentrations at admission reflect the presence of common cardiovascular risk factors and can predict cardiovascular events. In addition, the AA genotype and A allele of the GAS6 gene relate to ACS, which may have a protective role against ACS.

G protein beta2 subunit interacts directly with neuropathy target esterase and regulates its activity.

Neuropathy target esterase (NTE) was identified as the primary target of organophosphate compounds that cause a delayed neuropathy with degeneration of nerve axons. NTE is a novel phospholipase B anchored to the cytoplasmic face of endoplasmic reticulum and essential for embryonic and nervous development. However, little is known about the regulation of NTE. A human fetal brain cDNA library was screened for proteins that interact with NTE, Gbeta2 and Gbeta2-like I subunits were found to be able to bind the C-terminal of NTE in yeast. The interaction of Gbeta2 and NTE was confirmed by in vivo co-immunoprecipitation analysis in COS7 cells. Furthermore, depletion of Gbeta2 by RNA interference down regulated the activity of NTE but not its expression level. In addition, the activity of NTE was down regulated by the G protein signal pathway influencing factor, pertussis toxin, treatment in vivo. These findings suggest that Gbeta2 may play a significant role in maintaining the activity of NTE.

[Study of toxicity on male reproductive system of mice induced by SO2 inhalation].

OBJECTIVE: In this paper, toxicity of SO2 on male reproductive system of mice was studied. METHODS: 40 mice were divided to 4 groups (10/group): a group for control, the other 3 groups for SO2 inhalation (28, 56, 112mg/m3), 4h/d, 7d. RESULTS: The activities of GST and G-6-PD, as well as the content of GSH decreased significantly with SO2 increased. The content of MDA increased evidently with SO2 increased. CONCLUSION: SO2 can influence GSH oxidation-deoxidation system and cause DNA damage in male reproductive system of mice.