[Puerarin alleviates cognitive impairment and tau hyperphosphorylation in APP/PS1 transgenic mice].

To observe the effect of puerarin on learning and memory function and tau phosphorylation in APP/PS1 transgenic mice, drugs were administered to 3-month old APP/PS1 transgenic mice. Learning and memory function of mice were assessed by Morris water maze test 3 months after treatment. Animals were decapitated after behavioral test. The levels of Aß were detected by ELISA, the expression of protein [tau, phosphorylated tau, GSK3ß and p-GSK3ß(Ser9)] were assessed by Western blot. Morris water maze test showed that the escape latency of APP/PS1 double transgenic mice was significantly longer than that of the normal control group, and the residence time of the original quadrant was significantly shorter. The escape latency of puerarin group was significantly shorter and the residence time of the original quadrant was prolonged compared with the model group. Compared with the normal control group, the levels of Aß in the cortex of APP/PS1 transgenic mice were increased, the expression of phosphorylated tau was significantly increased, and the expression of phosphorylated GSK3ß(Ser9) protein was decreased. Treatment with puerarin, the latency of APP/PS1 transgenic mice was significantly reduced, the level of Aß was decreased, the expression of phosphorylated tau was significantly decreased, and the expression of phosphorylated GSK3ß(Ser9) protein was increased. Puerarin improves the learning and memory impairment by reducing the formation of Aß, activating the GSK3ß signaling pathway, inhibiting the phosphorylation of tau in APP/PS1 double transgenic mice.

HIV-infection resistance in PMBC-derived dendritic cells modified with recombinant virus.

This study aimed to identify the characteristics of recombinant-adenovirus-modified PBMC-derived dendritic cells and their resistance to HIV-1 infection by integrating the CCR5∆32, CCR5siRNA, HIV-1 pol and HIV-1 int genes into a recombinant adenovirus vector using the AdEasy system. Dendritic cells (DCs) were isolated from human PBMCs from blood of healthy donors. The expression of CCR5∆32, CCR5, CXCR4 and HIV-1 p24 in PBMCs or modified cells was measured by western blot, p24 expression in cell lysates was measured by ELISA, and HIV-1 entry was measured by ß-galactosidase assay. Furthermore, T-cell immunity induced by the recombinant adenovirus was measured by ELISPOT assay. After the cells were modified by Ad-R5∆32siRNA, the expression of CCR5∆32 increased, while the expression of CCR5 and CXCR4 decreased. There was no adverse effect of adenoviral gene transfer on DC development. CD83 expression on the surface of mature DCs did not change after gene transfer. The expression of p24 remained at low levels in modified cells when challenged by HIV-1. The modified cells showed resistance to HIV-1 infection. Results indicated that recombinant-adenovirus-modified cells demonstrated good resistance to HIV-1 infection. Modification of HSC-derived immune cells, such as DCs, may be a potent strategy to resist HIV-1 infection.

[Mechanisms of foam cell formation in smooth muscle cell derived from bone marrow stem cells].

OBJECTIVE: To establish a model of smooth muscle cells differentiated from bone mesenchymal stem cells (BMSC-SMCs) in vitro and explore the relationship between scavenger receptors A (SR-A) and caveolin-1. METHODS: BMSCs were isolated from the femoral bone of SD rats by adherent culture. After treatment of the BMSC-SMCs with 80 mg/L ox-LDL for 72 h, Western blotting was performed to detect the expression of scavenger receptor SR-A, cell cholesterol transport protein ATP-binding cassette transporter Al (ABCA1) and caveolin-1. RESULTS: BMCS-SMCs became foam cells after treatment with ox-LDL. BMSC-SMC gave rise to more foam cell formation than VSMCs did. Western blotting showed that treatment with 80 mg/L ox-LDL for 72 h resulted in significantly increased expression of SR-A and significantly decreased expressions of ABCA1 and caveolin-1. CONCLUSIONS: Treatment of BMCS-SMCs with ox-LDL results in cholesterol ester accumulation in the cells to result in foam cells, the mechanism of which involves up-regulation of scavenger receptor SR-A expression and down-regulation of the reverse cholesterol transport protein ABCA1 and caveolin-1 expression.

[Effect of oxidative low-density lipoprotein on the proliferation of bone marrow stem cell- derived smooth muscle cells].

OBJECTIVE: To establish the model of bone mesenchymal stem cell-derived smooth muscle cells (BMSC-SMCs) and investigate the role of BMSC-SMCs in the development and progression of artherosclerosis. METHODS: BMSCs were isolated from the femoral bone of SD rats by adherent tissue culture method, and vascular smooth muscle cells (VSMCs) were obtained from the thoracic aorta. The differentiation of BMSCs into BMSC-SMCs was induced in the conditioned medium. The specific markers of BMSCs and BMSC-SMCs were identified by immunofluorescence (IF) staining. After treatment with 80 mg/L oxidative low-density lipoprotein (ox-LDL) for 72 h, the growth characteristics of BMSC-SMCs and VSMCs were observed. Flow cytometry was applied to analyze the cell cycle of BMSC-SMCs and VSMCs. RESULTS: BMCS-SMCs transformed into foam cells after treatment with ox-LDL, which was more obvious in comparison with VSMCs. The growth curve of BMSC-SMCs and VSMCs presented with an S-shape pattern with the cell doubling time of 20 and 32 h, which was reduced to 15 and 28 h after treatment with 80 mg/L ox-LDL, respectively. Flow cytometry showed that exposure to 80 mg/L ox-LDL significantly increased G(0)/G(1) and decreased S and G(2)/M phase cells in both BMSC-SMCs (P<0.01, n=3) and VSMCs (P<0.05, n=3) in comparison with the control cells. CONCLUSION: BMSC-SMC might be involved in the formation of fatty core and accelerate the development of atherosclerosis.

[Inhibitory effects of Aspisol on growth of transplanted breast cancer in C3H mice].

BACKGROUND & OBJECTIVE: Cyclooxygenase (COX) plays an important role in tumorigenesis and development. Many inhibitors of COX could inhibit proliferation and induce apoptosis of cancer cells. This study was to observe the inhibitory effect of Aspisol on growth of transplanted breast cancer in C3H mice and the effects of Aspisol on tumor cell apoptosis and the expression of Caspase-3 and COX-2, and explore the mechanisms. METHODS: The suspension of breast cancer cells was injected subcutaneously into forelimb axillas of C3H mice to establish xenograft models. From the next day, the mice received intraperitoneal injection of different concentrations of Aspisol once a day for 28 days; the mice received injection of 5-fluorouracil (5-FU) were used as positive controls, and the mice received injection of normal saline (NS) were used as negative controls. The inhibition rate of tumor growth was calculated. Tumor cell apoptosis was detected by TUNEL assay. The expression of Caspase-3 and COX-2 was detected by immunohistochemistry. RESULTS: The inhibition rate of tumor growth was 38.9% in 175 mg/kg Aspisol group, 48.2% in 350 mg/kg Aspisol group, 47.0% in 700 mg/kg Aspisol group, and 60.4% in 10 mg/kg 5-FU group. Typical apoptotic morphologic changes were seen in the 4 groups. Caspase-3 expression was significantly higher and COX-2 expression was significantly lower in Aspisol groups than in NS group. CONCLUSIONS: Aspisol may inhibit the growth of transplanted breast cancer in C3H mice, and induce tumor cell apoptosis. The mechanism may be correlated to down-regulation of COX-2 and up-regulation of Caspase-3.