The purpose of this study is to evaluate the anti-aging effects and reveal the underlying mechanism of Scutellaria baicalensis Georgi ethanol extract (SBG) in D-galactose-induced rats. Fifty rats were randomly divided into five groups: vehicle control group, D-galactose group, and D-galactose combined with 50, 100, 200 mg x kg(-1) SBG. A rat aging model was induced by injecting subcutaneously D-galactose (100 mg x kg(-1)) for ten weeks. At the tenth week, the locomotor activity (in open-field test) and the learning and memory abilities (in Morris water maze test) were examined respectively. The urine was collected using metabolic cages and analyzed by high-resolution 1H NMR spectroscopy combined with multivariate statistical analyses. The SBG at doses of 50, 100 and 200 mg x kg(-1) treatments groups could significantly ameliorate aging process in rats' cognitive performance. The 50, 100, 200 mg x kg(-1) SBG regulated citrate, pyruvate, lactate, trimethylamine (TMA), pantothenate, β-hydroxybutyrate in urine favorably toward the control group. These biochemical changes are related to the disturbance in energy metabolism, glycometabolism and microbiome metabolism, which is helpful to further understanding the D-galactose induced aging rats and the therapeutic mechanism of SBG.

OBJECTIVE To investigate the dynamic changes in urine metabolic profiles in rats induced by D-galactose (D-Gal),and to study the correlations between the differential metabolites and behavior indicators using the proton nuclear magnetic resonance (1H-NMR)-based metabonomics.METHODS Subcutaneous injection of D-Gal 100 mg· kg-1 for 10 weeks was adopted in the model group.The sample of urine was collected at day 0 (dO),d14,d28,d42,d56 and d70.NMR metabonomics technique was used for acquisition of data,which was analyzed by multivariate statistical analysis.The ability of learning and memory were measured by Morris water maze test from d70.After the behavioral test,the rats were sacrificed and the hippocampus was observed by hematoxylin-eosin staining.RESULTS Principal component analysis (PCA) results revealed that there was considerable difference between the model group and the normal control group at d70.According to the varible importance plot (VIP) calculation and S-plot scores,a total of 12 metabolites were screened and identified as potential biomarkers at d70.The differences of metabolites and Morris water maze test were subjected to correlation analysis,and the results showed that the levels of choline,lactate and dimethylglycine in the model group were significantly increased and negatively correlated with the times of crossing the platform (r =-0.90,-0.50 and-0.52;n=10).Formate was significantly negatively correlated with the time spent in the target area (r =-0.51,n=10),but choline and formate were significantly positively correlated with the escape latency (r =0.72 and 0.53;n=10).However,the levels of creatine and taurine decreased in the model group,which was significantly positively correlated to the times of acrossing platforms (r =0.89 and 0.71;n=10),while alanine was significantly positively correlated to the time spent in the target area(r =0.74,n=10).Taurine,alanine and creatine were significantly negatively correlated with the escape latency (r =-0.66,-0.50 and-0.85;n=10).The correlations between the differential metabolites and the behavioral indicators were further proved.CONCLUSION The metabolic profile changes in urine from D-Gal induced aging model rats are significantly correlated with impairement of ability in learning and memory.1H-NMR metabonomics in urinary metabolic profile changes may be used as an evaluation index in the D-Gal induced aging rats model.

Objective To construct a new secreting recombinant hIFN-?-2B-BCG to provide a new tool for the treatment of bladder tumor. Methods BCG was genetically engineered to secrete recombinant human interferon-alpha 2B by transforming of shuttle plasmid phIFN-?-2B. Expression of hIFN-? was readily detectable by ELISA. Results The phIFN-?-2B was transformed in BCG correctly,and the value of hIFN-?-2B in supernatant of recombinant BCG culture was calculated to approximately 997.2 pg/ml. Conclusions This study demonstrates that the recombinant phIFN-?-2B can be expressed in BCG secretively. As the construction of the plasmid and its transformation and expression in BCG were accomplished successfully, a foundation of reformed BCG and new vaccine will be established.

Objective:To investigate the role of CD8 + T cells in lethal Plasmodium yoelii 17XL ( Py 17XL) infection. Methods:BALB/c mice and C57BL/6 mice were infected with Py 17XL-infected red blood cells (1×10 6 cells/0.1 ml) through intraperitoneal injection to establish the mouse models of Py 17XL infection. Parasitemia (the percentage of erythrocytes infected with Py 17XL) and the survival rates of the mice was observed dynamically. Flow cytometry was used to detect the number of effector T cells (T EFF) and central memory T cells (T CM) of CD8 + T cell subpopulations, the expression of IFN-γ and granzyme B (GB) levels, and the expression of surface chemokine receptors CXCR3, CXCR6 and CX3CR1. FTY720 blocking experiment was conducted on Py 17XL-infected C57BL/6 mice to analyze the impact of CD8 + T cell migration on Py 17XL infection. Results:The parasitemia of BALB/c mice increased rapidly 5 d after infection and reached the peak on 8 d [(79.57±3.82)%]. Besides, the parasitemia was higher in BALB/c mice than in C57BL/6 mice 5-8 d after infection ( P<0.000 1). All BALB/c mice died on 9 d. The parasitemia of C57BL/6 mice reached the peak on 14 d [(48.19±3.19)%] and then decreased to 0 on 26 d. There was statistically significant difference in the survival rate between the two groups ( P<0.000 1). Flow cytometry results showed that compared with the BALB/c mice, the absolute number of CD8 + T cells in spleen and liver tissues and the number of CD8 + T EFF and CD8 + T CM cells in spleen and lymph nodes of C57BL/6 mice increased significantly ( P<0.05). Compared with the BALB/c mice, the levels of GB, IFN-γ and chemokines expressed by CD8 + T cells in spleen and liver tissues of C57BL/6 mice increased significantly ( P<0.05). The FTY720 blocking experiment showed that the survival rate, the absolute number of CD8 + T cells in liver and spleen, and the number of CD8 + CXCR3 + T cells decreased significantly in the experimental group ( P<0.05). Conclusions:CD8 + T EFF and CD8 + T CM cells contribute to resistance against Py 17XL infection by secreting GB and IFN-γ. The chemokine receptor CXCR3 plays an important role in mediating the chemotaxis of CD8 + T cells to spleen and liver.

Objective To explore the impact of pH value of the reaction system on the properties of bovine hemoglobin modified with aldehydeated polyethylene glycol(PEG-bHb).Methods PEG-bHb conjugates were synthesized under varying pH conditions(6.0,6.5,7.4 and 8.0)of the reaction system while consistent molar ratios,temperature,and reaction time were maintained.The structural and functional attributes of PEG-bHb were characterized.Results The proportion of methemoglobin decreased with an increase in pH.In a weakly acidic reaction environment,the PEG-bHb was found to be relatively highly modified.At pH 6.5,the average number of PEG chains attached to the bHb surface was 6.86±0.38.Selective PEG modification of the N-terminal α-NH2 groups was more pronounced under weakly acidic conditions.Specifically,at pH 6.5,the modification efficiency of the N-terminal α-NH2 groups of bHb by aldehyde-activated PEG reached 95.4％for the α-chains and 99.3％for the β-chains.The PEG modification influenced the heme region microenvi-ronment of bHb,with minimal structural impact observed at pH 6.5.After modification,the oxygen affinity of PEG-bHb was enhanced,the Hill coefficient was reduced,and there were significant increases in colloid osmotic pressure,viscosity,and particle size,all of which differed markedly from the unmodified bHb group(P＜0.001).Conclusion The synthesis of PEG-bHb under weakly acidic conditions can result in a high degree of selective modification of the N-terminal α-NH2 groups and an overall high degree of modification.