Abstract:Located in the cytoplasm, mitochondria and nucleus in the form of soluble dimers, DJ-1 is a recognized Parkinson′s disease (PD)-related protein since its gene mutation leads to the early onset of autosomal recessive PD. Under oxidative stress which is closely related to the pathogenesis of PD, DJ-1 exerts its neuroprotective effects by sensing oxidative stress, changing gene expression, and participating in the regulation of AKT, ASK and other important signaling pathways.

Abstract:It has been show that motor imagery can clearly improve the brain function and it has been widely applied in sports training and motor rehabilitation therapy. Recently, with the appearance of imaging system, such as functional Magnetic Resonance, the method of the neuroimaging became more complexity. Then the mechanism of motor imagery had been deeply understood, especially in the cooperation with the multi-encephalic regions. The mechanism of motor imagery and its application in motor rehabilitation were briefly introduced.

Abstract:PHF8(PHD finger protein 8) is a Fe²⁺ and 2-oxoglutarate dependent histone lysine demethylase and belongs to a family of JmjC domain-containing proteins. PHF8 also contains a plant homeodomain (PHD) finger motif in its N-terminus, which involves in transcriptional regulation. PHF8 can demethylate H3K9me2/1, H4K20me1 and H3K27me2 with JmjC domain, and also act as a transcriptional coactivator through binding to H3K4me3 via PHD finger. PHF8 regulates expression of rRNA and many protein-coding genes involved in neural development such as JARID1C. Mutations in human PHF8 which are defective in histone demethylase activity can cause inherited X-linked mental retardation(XLMR) and cleft lip/cleft palate. These researches suggested that PHF8 is an important regulator of neural development, which deepens the understanding of histone methylation with gene expression and provides novel clues to understanding of XLMR.

Abstract:Interleukin-18(IL-18) is a new member of IL-1 cytokine family and known as IFN-γ-inducing factor previously. An increased secretion of IL-18 is generally a marker for many chronic inflammation and autoimmune disorders, implying its involvement in inflammatory responses. Here, it was showed that IL-18 stimulated the expression of CSF-1 in Jurkat T lymphocytes that might be a manifestation for IL-18 to play its biological functions in inflammatory pathogenesis. The signaling mechanism that contributes to IL-18-induced transcriptional activation of CSF-1 was investigated further. Combined data suggested a MyD88-NF-κB-CSF-1 signal pathway is involved in the up-regulated expression of CSF-1.

Abstract:To investigate the effects of dendritic cells on T lymphocyte proliferation and apoptosis, providing an in vitro model of clinical transplant immunological tolerance. After mature dendritic cells ( mDCs) from peripheral blood of healthy adults was successfully transfected with human FasL gene, mDCs were analyzed for the expression of cell surface molecules, antigen presenting function and their apoptosis. Effects of mDCs on T lymphocyte proliferation and apoptosis were further detected based on co-culture of mDCs and T lymphocytes. The results show that, FasL did not significantly change the expression level of mDC's surface molecules CD40, CD80, CD86 and HLA-DR; FasL did not induce apoptosis of mDC. No effects on the antigen presenting function of mDC were observed as well. The mDC transfected with FasL decreased stimulation index and increased apoptosis of allogeneic T-lymphocyte significantly. So that, human mDCs transfected with FasL may regulate T lymphocyte proliferation and apoptosis without alteration of cell surface molecules and antigen presentation characteristics on human mDC.

Abstract:It was investigated whether the effects of sinusoidal electromagnetic field (SEMF) stimulation on the differentiation and mineralization of osteoblast are mediated by the nitric oxide (NO) signal pathway. It was first investigated whether SEMF had an effect on nitric oxide synthase (NOS) activity measured on the 0 h, 0.5 h, 1 h, 1.5 h, 2 h, 2.5 h, 3 h, 3.5 h, 4 h after SEMF treatment. Secondly, the NOS inhibitor, L-nitro-arginine-methylester (L-NAME) was added to the culture medium to observe whether it inhibit the maturation and mineralization of osteoblast stimulated by SEMF, which evaluated by measuring alkaline phosphatase (ALP) activity, CFU-F_ALP, osterix gene expression and mineralized bone modulus. After treatment of SEMF, the NOS activity in SEMF group increased in comparison with the normal control group (P < 0.01), reaching the highest level after 0.5 h. The gene expression of Osterix, ALPase activity and mineralized bone modulus in the SEMF group were also increased significantly. However, these effects were partially blocked in the L-NAME group．Surprisingly, all the osteogenic markers in the SEMF+L-NAME group were slightly higher than those of the control group, but lower than those of the SEMF group．In conclusion, The NO signal pathway was activated by SEMF treatment．The stimulatory effects of SEMF on the differentiation and mineralization of osteoblast were attenuated when NO signal pathway was blocked.

Abstract:The complex (IN_L708, 906) model of HIV-1 integrase with L708, 906 inhibitor was obtained via molecular docking method in previous work. The key residues of IN_L708, 906 complex model were detailedly analyzed from the three perspectives (i.e. distance, energy and hydrogen bond). The results show that the complex model is similar to the IN_5CITEP complex structure from proteins data bank. The difference of the motion modes and correlativity between IN_L708, 906 model and IN monomer was investigated with principal component analysis and dynamical cross-correlation map methods. The computational results indicate that the association with L708, 906 leads to the flexibility decrease of functional loop region, the lose of regular motion, as well as the disordered increase of correlative motion, which may be the main reasons for the activity attenuation of IN. All the simulation results may help the anti-HIV drug design based on the structures of Aryl diketoacids.

Abstract:Complex network has been used to analyze the global and local properties of cell processes such as gene regulation, protein-protein interaction and signal transduction. A molecular network of integrin-mediated cell adhesions is constructed by data-mining and presented by a visualizing software. The network consists of 156 components linked by 690 interactions, with an average node degree of 8.66, an average cluster coefficient of 0.24 and an average path length of 2.6. Several functional modules are involved in switching on or off many of the molecular interactions within the network, consequently affecting cell adhesion, migration and cytoskeletal organization. Screening and examination of the adhesome network motifs reveals a relatively small number of key motifs, dominated by 3-nodes (three-component complexes). The role of the different network modules and modifs in regulating cell adhesions is also discussed.

Abstract:Val-Glu-Pro(VEP) is an angiotensin Ⅰ-converting enzyme (ACE) inhibitory peptide derived from Spirulina platensis. The antihypertensive effect of VEP in spontaneously hypertensive rats (SHRs) was investigated in 24 h after one single dose and in one-week with one single dose per day. The expression regulation of VEP on major components of the renin-angiotensin system (RAS) in the kidney and serum of the SHRs was also explored with Real-Time PCR and enzyme-linked immunosorbent assay (ELISA). The results indicated that the least effective dose of VEP was 5 mg/kg and it exhibited a dose-dependent manner with increased dosages. The lowest weighted systolic blood pressure (WSBP) and weighted diastolic blood pressure (WDBP) occurred in 6 h and 4 h after administration, respectively. During the one-week experiment course, the WSBP of the VEP-treated group (10 mg/kg) was significantly lower than that of the negative control group from the 5th day. Furthermore, the VEP treatment significantly down-regulated the mRNA expression of renin, ACE, and the angiotensinⅡ(AngⅡ) type 1 (AT1) receptor, and up-regulated the mRNA expression of the AngⅡ type 2 (AT2) receptor in the kidney of the SHRs, suggesting that the antihypertensive effect of VEP might be related to its inhibition on the RAS and that it might be of great prospects in prevention and treatment of hypertension.

Abstract:Hepatic stellate cells(HSC) in tumor microenviroment infiltrate the hepatocellular carcinoma(HCC) stroma, and they play a critical role in HCC progression. Epimorphin ( EPM, also called syntaxin2 ), a mesenchymal cell surface-associated molecule expressed in HSC, is a key regulator for liver progenitor cells differentiation,especially during the course of tubulogenesis. It has been reported that the dysfunction of EPM is related to ulcerative colitis, interstitial pneumonia and colon carcinoma. Therefore, the development of an EPM-knockdown HSCs will be highly beneficial in such studies. Stable EPM-knockdown transgenic cell lines were generated by transfecting human hepatic stellate cells with RNA interference(RNAi) plasmids. Reverse transcriptase polymerase chain reaction(PCR) analyses and Western blot indicated that the mRNA and protein levels of EPM in the transgenic cell lines were significantly lower than that in control. Conditioned media (CM) collected from the transgenic cell lines significantly decreased migration of HCC cells cultured in monolayers and transwells. HCCs and HSCs were co-cultured in 3D model, knocked-down EPM HSCs generated bigger spheroid culfures than control, the phenomenon also demonstrated that EPM could promote HCCs migration. The results show that RNAi can be used to stably knock down expression of EPM in human hepatic stellate cells and further improvements in related technologies will facilitate the studies of its roles in HCC tumorgenesis, proliferation and migration.

Abstract:It is an important means to record rat hippocampal field potential, especially in vivo recording, in the study of learning and memory. To overcome the disadvantages and inconvenience in current hippocampal field potential recording and raise in vivo experimental efficiency, stimulation/recording/drug delivery system for in vivo hippocampal field potential recording was developed and applied. Anesthetized SD rats were fixed in a stereotaxic device and a homemade stimulation/recording/drug delivery system was used to record field excitatory postsynaptic potential (fEPSP) in hippocampal CA1 area. The results showed that fEPSPs were easily evoked by nearly every test stimulus and maintained steadily for a long time by using the stimulation/recording/drug delivery system; high frequency stimulation (HFS) successfully induced early-phase LTP (E-LTP) and 1ate-phase LTP (L-LTP); the baseline fEPSPs and LTP were promptly and effectively suppressed by intrahippocampal injection (IH) of AMPA receptor antagonist CNQX (100 μmol/L, 1 μl) and NMDA receptor antagonist AP-5 (100 μmol/L, 1 μl) , respectively, with a shorter latency and a reduced dose compared with intracerebraventricular injection (ICV); the induction and recording of paired pulse facilitation (PPF) were also considerably easy and stable using the combination device. In short, the simplicity, reliability and high efficiency of stimulation/recording/drug delivery combination system in recording in vivo rat hippocampal CA1 area field potential make it more practical in the research of synaptic plasticity, and this technique established an important foundation for the study of higher cognitive brain function.

Abstract:Site-directed mutagenesis plays important roles to study protein structure-function relationship and the researchers are always confronted with the problem on how to generate a point mutation of a target gene efficiently. A novel strategy to produce a point mutation was depicted based on inverse PCR with PIAS3 as an example. Firstly, the entire PIAS3 coding sequence was amplified from MCF-7 cDNA and then cloned into the expression vector pXJ40-myc. Two sets of PIAS3 primers with specific mutation sequences were synthesized and then phosphorylated at their 5′ terminus. Inverse PCR was performed with the phosphorylated primers as well as with the plasmid pXJ40myc-PIAS3 as the template. Further, the PCR products were subjected to DpnⅠ treatment, agarose gel purification, self-ligation and transformation into DH5α. Three colonies were randomly selected for DNA sequencing. The expression of both the PIAS3 wide type and the point mutants( PIAS3 K110R and K411,412R) was analyzed by transfection of these plasmids into 293T cells. The result showed that the PIAS3 K110R and K411,412R point mutants were successfully constructed and expressed in mammalian cells, which suggested that the novel inverse PCR stratagy can be applied to construct the point mutants of a target gene efficiently and conveniently.