Effects of astaxanthin on oxidative stress and inflammatory reaction in rats with traumatic brain injury based on Nrf2/HO-1 signaling pathway / 中国药房

OBJECTIVE To investigate the effects of astaxanthin on oxidative stress and inflammatory reaction in rats with traumatic brain injury （TBI）. METHODS Male SD rats were randomly divided into sham operation group， model group， astaxanthin low-dose group （20 mg/kg）， astaxanthin high-dose group （40 mg/kg）， astaxanthin+ML385 group [astaxanthin 40 mg/kg+ nuclear factor-erythroid 2-related factor 2 （Nrf2） inhibitor ML385 30 mg/kg]， with 14 rats in each group. Except for the sham operation group， TBI model was induced by the modified Feeney free-fall impact method in other groups. The rats in each drug group were given the corresponding drug intragastrically or intraperitoneally， and the rats in the sham operation group and model group were intragastrically given a constant volume of normal saline. The neurological function of rats in each group was scored on the 1st， 3rd and 7th day after drug intervention； on the 7th day of drug intervention， the changes of cerebral histomorphology and inflammatory infiltration score were observed in each group， and the ultrastructure of nerve cells in brain tissue was also observed. The contents of oxidative stress indexes [superoxide dismutase （SOD）， catalase （CAT）， glutathione peroxidase （GSH-Px）， malondialdehyde （MDA）， nitric oxide （NO）] and inflammatory reaction indexes [tumor necrosis factor-α， interleukin-1β （IL-1β）， IL-6， inducible nitric oxide synthase] as well as protein and mRNA expressions of Nrf2， heme oxygenase-1 （HO-1） and NAD（P）H： quinone oxidoreductase 1 （NQO1） were detected in cerebral tissue. RESULTS Compared with the sham operation group， the brain edema of rats in the model group was obvious， accompanied by a large number of inflammatory cells infiltrated， the shape of organelles was damaged and their number was reduced， and the ultrastructure of nerve cells was seriously damaged. The neurological function score， the contents of SOD， CAT， GSH-Px and NO and the relative expression levels of Nrf2， HO-1 and NQO1 protein and mRNA in brain tissue were significantly decreased， while the inflammatory infiltration scores， the contents of MDA and inflammatory reaction indexes were significantly increased （P＜0.05）. Compared with the model group， low-dose and high-dose astaxanthin could significantly improve the pathological status of brain tissue and nerve cells and neurological function scores （except for the first day of drug intervention in the astaxanthin low-dose group）， increase the contents of SOD， CAT， GSH-Px and NO and the relative expression levels of Nrf2， HO-1， NQO1 protein and mRNA in brain tissue in a dose-dependent manner， and reduce inflammatory infiltration scores， the contents of MDA and inflammatory reaction indexes （P＜0.05）. ML385 could significantly inhibit the above effects of astaxanthin （P＜0.05）. CONCLUSIONS Astaxanthin may reduce the oxidative stress of TBI model rats， alleviate the neurological damage and reduce the level of inflammation reaction by activating the Nrf2/HO-1 signaling pathway.

A novel pH-stable, endoglucanase (JqCel5A) isolated from a salt-lake microorganism, Jonesia quinghaiensis

Background: Endoglucanase, one of three type cellulases, can randomly cleave internal p-1,4-linkages in cellulose polymers. Thus, it could be applied in agricultural and industrial processes. Results: A novel endoglucanase gene (JqCel5A) was cloned from Jonesia quinghaiensis and functionally expressed in Escherichia coli Rosetta (DE3). It contained 1722 bp and encoded a 573-residue polypeptide consisting of a catalytic domain of glycoside hydrolase family 5 (GH5) and a type 2 carbohydrate-binding module (CBM2), together with a predicted molecular mass of 61.79 kD. The purified JqCel5A displayed maximum activity at 55°C and pH 7.0, with 21.7 U/mg, 26.19 U/mg and 4.81 U/mg towards the substrate carboxymethyl cellulose, barley glucan and filter paper, respectively. Interestingly, JqCel5A exhibited high pH stability over a broad pH range of pH (3-11), and had good tolerance to a wide variety of deleterious chemicals including heavy metals and detergent. The catalytic mechanism of JqCel5A was also investigated by site mutagenesis and homology-modeling in this study. Conclusions: It was believed that these properties might make JqCel5A to be potentially used in the suitable industrial catalytic condition, which has a broad pH fluctuation and/or chemical disturbance.

Association of chromosome 17q copy number variation with overall survival of patients with hepatocellular carcinoma and screening of potential target genes / 中华医学遗传学杂志

OBJECTIVE To assess the association of copy number variations (CNVs) in chromosome 17q with the overall survival(OS) of patients with hepatocellular carcinoma(HCC), and to screen for target genes contained in the OS-related CNVs. METHODS A total of 174 HCC cases were enrolled. For 66 patients, the follow-up data was available. High-resolution Agilent Hu-244A array comparative genomic hybridization (aCGH) and Affymetrix U133 Plus 2.0 expression arrays were used to detect CNVs and gene expression of genes from the 17q region, respectively. The association of CNVs and OS was assessed with Log-rank test, Kaplan-Meier survival analysis, and Cox proportional hazards models. The gene expression in HCCs with 17q gain, HCCs without, and non-tumor liver tissues were compared with a Mann-Whitney U test. RESULTS Univariate association analysis showed that copy number gain in 17q25.1-25.3 was significantly associated with reduced OS (Log-rank test, P = 0.00002), and HCC cases with 17q25.1-25.3 gain had a 4.76-fold (95%CI: 2.31-9.81) increased hazard ratio (HR) for death from HCC, as compared to those without the gain. Multivariate Cox proportional hazards regression model revealed 17q25.1-25.3 gain to be an independent prognostic marker for poor OS (HR = 3.17, 95%CI: 1.39-7.26, P = 0.006). The expression levels of 18 genes in 17q25.1-25.3 including SLC9A3R1, GRB2, and TK1 were significantly increased in HCCs with gain than in those without (all P < 0.01) and non-tumor liver tissues (all P < 0.01). CONCLUSION The association of 17q25.1-25.3 gain with reduced OS has indicated that it is a prognostic marker for poor patient survival in HCC, for which SLC9A3R1, GRB2, and TK1 are candidate genes.

A new method for establishing temperature gradient field in micro-channel on glass-PDMS microfluidic chip and for investigating thermal biological effect of cells / 军事医学

Objective To develop a new method for establishing a temperature gradient field in the microchannel on a glass-polydimethylsiloxane ( PDMS ) microfluidic chip and to verify its applicability in the study of cellular thermal biological effect.Methods The establishment and control of the temperature gradient field in the microchannel were implemented by a peripheral indium tin oxide ( ITO) heater and a heating micro-wire embedded in the PDMS chip.The temperature gradient field established in the microchannel was represented by the finite element numerical analysis and temperature-dependent fluorescent dye rhodamine B.Finally, the thermal biological effect, which used cell survival rate of human prostate cancer cells T24 as an indicator, was investigated in the microchannel.Results The results of finite element numerical analysis proved that this method established a temperature gradient field along the length of the microchannel successfully.The distribution range of the temperature gradient field was controlled by the ITO heater, while the gradient of the temperature gradient field was controlled by the heating micro-wire.The measurement result of rhodamine B was identical with the result of the finite element numerical analysis.The thermal biological effect of T24 tumor cell research showed that the cell survival rate decreased with the rise of the regional temperature in the microchannel.Conclusion The method developed in this paper for establishing a temperature gradient field in the microchannel on a glass-PDMS microfluidic chip is simple and easy to implement, and it can be used for parallel study of the cellular thermal biological effect on the microfluidic chip in the future.