摘要:
患者,男,15岁.皮肤结节性肿胀13年,因频繁出现胸闷,呼吸困难等心肌缺血表现,于2003年4月来我院动脉硬化高脂血症门诊就诊.患者13年前出现皮肤结节性肿胀,4年前出现心肌缺血的表现,眼角膜出现角膜弓.体检血压135/90 mm Hg(1 mm Hg=0.133kPa),双肘部以及跟腱可见多个散发的黄色结节,双手及臀部可见多发弥散小结节,眼睑周围有米粒大小结节,质地较硬,无疼痛.眼角膜下缘有半月形阴影.
关键词:
onychin;vascular smooth muscle;cell cycle;retinoblastoma;cyclin D1;cyclin E;tyrosine kinase;mitogen-activated protein kinase
摘要:
Aim: To investigate the effects of onychin on the proliferation of cultured rat artery vascular smooth muscle cells (VSMCs) in the presence of 10% new-born calf serum (NCS).Methods: Rat VSMCs were incubated with onychin 150 mol/L or genistein 10 mol/L in the presence of 10% NCS for 24 h. The proliferation of VSMCs was measured by cell counting and MTS/PMS colorimetric assays. Cell cycle progression was evaluated by flow cytometry. Retinoblastoma (Rb) phosphorylation, and expression of cyclin D1 and cyclin E were measured by Western blot assays. The tyrosine phosphorylation of ERK1/2 was examined by immunoprecipitation techniques using anti-phospho-tyrosine antibodies.Results: The proliferation of VSMCs was accelerated significantly in the presence of 10% NCS. Onychin reduced the metabolic rate of MTS and the cell number of VSMCs in the presence of 10% NCS in a dose-dependent manner. Flow cytometry analysis revealed that the G1-phase fraction ratio in the onychin group was higher than that in the 10% NCS group (85.2%vs 70.0%, P< 0.01), while the S-phase fraction ratio in the onychin group was lower than that in 10% NCS group (4.3%vs 16.4%, P< 0.01). Western blot analysis showed that onychin inhibited Rb phosphorylation and reduced the expression of cyclin D1 and cyclin E. The effects of onychin on proliferation, the cell cycle and the expression of cyclins in VSMCs were similar to those of genistein, an inhibitor of tyrosine kinase. Furthermore immunoprecipitation studies showed that both onychin and genistein markedly inhibited the tyrosine phosphorylation of ERK1/2 induced by 10% NCS.Conclusion: Onychin inhibits the proliferation of VSMCs through G1 phase cell cycle arrest by decreasing the tyrosine phosphorylation of ERK1/2, and the expression of cyclin D1 and cyclin E, and sequentially inhibiting Rb phosphorylation.
关键词:
random peptide phage library;vascular endothelial cell;whole-cell screening;cell adhesion;caveolin-1;eNOS
摘要:
Using oxidized low-density lipoprotein (LDL)-injured vascular endothelial cells (ECs) as target cells, peptides specifically binding to the injured ECs were screened from a phage-displaying peptide library by using the whole-cell screening technique after three cycles of the “adsorption-elution-amplification” procedure. Positive phage clones were identified by ELISA, and the inserted amino acid sequences in the displaying peptides were deduced from confirmation with DNA sequencing. The adhesion rate of ECs to monocytes was evaluated by cell counting. The activity of endothelial nitric oxide synthase (eNOS), and the expression levels of caveolin-1 and intercellular adhesion molecule-1 (ICAM-1) were determined by Western blotting. Six positive clones specifically binding to injured ECV304 endothelial cells were selected from fourteen clones. Interestingly, four phages had peptides with tandem leucine, and two of these even shared an identical sequence. Functional analysis demonstrated that the YCPRYVRRKLENELLVL peptide shared by two clones inhibited the expression of ICAM-1, increased nitric oxide concentration in the culture media, and upregulated the expression of caveolin-1 and eNOS. As a result, the adhesion rate of monocytes to ECV304 cells was significantly reduced by 12.1%. These data suggest that the anti-adhesion effect of these novel peptides is related to the regulation of the caveolin-1/nitric oxide signal transduction pathway, and could be of use in potential therapeutic agents against certain cardiovascular diseases initiated by vascular endothelial cell damage.
摘要:
This study examined whether genistein influences the production of nitric oxide (NO) and expression of endothelial nitric oxide synthase (eNOS) and the modulators of eNOS activity in ovariectomized (OVX) rat hearts. Female mature Sprague-Dawley rats were subjected to bilateral ovariectomy, OVX rats were randomly divided into four groups: 17beta-estradiol (0.1 mg/kg, s.c. daily) was used as the positive control; low dose of genistein (0.5 mg/kg, s.c. daily); high dose of genistein (5.0 mg/kg, s.c. daily) and model. Sham operations as controls, the treatment lasted 6 weeks. Blood pressure, heart rate, plasma estradiol, heart and uterine weights were measured. Nitrite production in the myocardium was determined by nitrate reductase method. Protein level of eNOS, caveolin-1 and calmodulin was determined by Western blot. The results showed that nitrite production and eNOS protein in homogenized ventricular tissue was attenuated by approximately 53% and 67% in OVX rats compared with those in sham rats, respectively. Genistein increased nitrite production in rat heart in a dose-dependent manner, genistein at the dose of 5 mg/kg.d(-1) resumed nitrite production to a level similar to that in sham operated rats. Administration of genistein also increased eNOS protein expression in OVX rats myocardium with a concomitant decrease in the expression of caveolin-1, an endogenous eNOS inhibitory protein. Another eNOS stimulatory protein, calmodulin, was unchanged in these treatments. These effects were also observed in rats treated with 17beta-estradiol. Genistein at the dose of 5.0 mg/kg.d(-1) augmented uterine weight but this side effect in reproductive system was less than that of 17beta-estradiol. These results suggest that genistein supplementation and estrogen replacement therapy directly increase eNOS functional activity and NO production in the hearts of the OVX rats, but genistein has less side effects on the reproductive system than 17beta-estradiol.
作者机构:
[张洹] Institute of Hematolosy, Jinan University Medical College, Guangzhou 510632, China;Institute of Pharmacy and Pharmacology, Nanhua University, China;[雷小勇] Institute of Hematolosy, Jinan University Medical College, Guangzhou 510632, China, Institute of Pharmacy and Pharmacology, Nanhua University, China
通讯机构:
[Huan Zhang] I;Institute of Hematology, Jinan University Medical College, Guangzhou
摘要:
Objective: To investigate the effect of two antisense oligonucleotides on cell surviving, bcl-2 expression and apoptosis of leukemia cells. Methods: The experimental assays were performed with cell culture, immunochemistry and flowcytometry. Results: The two antisense oligodeoxynucleotides, combined with Vp16 or Ara-c or DNR, were able to decline the survival rate of myeleukemic cells, downregulate bcl-2 gene expression and induce apoptosis of leukemic cells significantly, as compared with Vp16 or Ara-c or DNR alone. Conclusion: It is possible for the two new bcl-2 antisenses to be developed into clinical trials for leukemia and tumor with bcl-2 gene overexpression.
摘要:
To investigate the inhibitory effect of the Bcl-XL small interfering RNA (siRNA) on Bcl-XL gene expression in the human gastric cancer cell line MGC-803, green fluorescent protein (GFP) siRNA was constructed and transfected into MGC-803 cells, together with GFP expression vector pTrace SV40. GFP expression levels were observed using fluorescence microscopy. Bcl-XL siRNA and negative siRNA were then constructed and stably transfected into MGC-803 cells. RT-PCR and immunofluorescence were used to detect the expression of Bcl-XL. Spontaneous apoptosis was detected by acridine orange (AO) and flow cytometry. Results were as follows: (1) 48 h after GFP expression vector and GFP siRNA co-transfection, the expression level of GFP in the GFP siRNA group was much lower than the negative siRNA group, according to fluorescence microscopy results. The mRNA and protein levels of Bcl-XL in Bcl-XL siRNA stable transfectants were reduced to almost background level compared with negative siRNA transfectants or untreated cells. (2) Changes in nucleus morphology was observed by AO staining nucleic and flow cytometry analysis, which showed that stable Bcl-XL siRNA transfectants have an increased spontaneous apoptosis (21.17%±1.26% vs. 1.19%±0.18% and 1.56%±0.15% respectively, P<0.05 vs. negative siRNA or untreated control). siRNA targeting GFP or Bcl-XL genes can specifically suppress GFP or Bcl-XL expression in MGC-803 cells, and Bcl-XL siRNA can increase spontaneous apoptosis. Bcl-XL siRNA may be a beneficial agent against human gastric adenocarcinoma.