Effect of Huanglian Jiedutang on Learning and Memory Ability and Cholinergic System in AD Rats Induced by Aβ1-42 / 中国实验方剂学杂志

Objective:To investigate the effects of Huanglian Jiedutang on learning and memory ability and the cholinergic system in Alzheimer's disease（AD） rats induced by amyloid <italic>β</italic>-protein（A<italic>β</italic>）_1-42. Method:Sixty male SD rats were divided into normal group， model group， huperzine A group （2.1×10^-5 g·kg^-1）， high-， medium- and low dose of Huanglian Jiedutang groups （6，3，1.5 g·kg^-1）. AD rat model was replicated by hippocampal injection of A<italic>β</italic>_1-42. After 4 weeks of treatment， Morris water maze test was performed. Hematoxylineosin （HE） staining was used to observe the pathological changes of rat hippocampus. Sampling blood from abdominal aorta was taken. Acetylcholine （ACh）， acetylcholinesterase （AchE） and choline acetyltransferase （ChAT） in serum and hippocampus were detected by enzyme-linked immunosorbent assay （ELISA）. The expression of hippocampal <italic>α</italic>7 nicotinic acetylcholine receptor （<italic>α</italic>7nAChR） protein was detected by Western blot. The expression of hippocampal <italic>α</italic>7nAChR mRNA was detected by Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR）. Result:Compared with the normal group， there were obvious pathological changes in the model group，such as neuron necrosis in the cerebral cortex，pyramidal cell or granular cell necrosis in the hippocampus，disorder of arrangement and inflammatory cell infiltration，prolonged escape latency，decreased escape platform times，decreased residence time in the effective area and swimming path in the effective area （<italic>P<</italic>0.05，<italic>P<</italic>0.01）. The contents of <italic>α</italic>7nAChR mRNA，ACh，AchE，ChAT，<italic>α</italic>7nAChR in the hippocampus decreased （<italic>P<</italic>0.01）. Compared with the model group，the escape latency of the middle dose group was shorter （<italic>P<</italic>0.05）， the escape platform times，the swimming path in the effective area and the residence time in the effective area increased （<italic>P<</italic>0.05，<italic>P<</italic>0.01）， the contents of serum ACh，ChAT， hippocampal AchE，ChAT and <italic>α</italic>7nAChR increased （<italic>P<</italic>0.05，）. The expression of hippocampal <italic>α</italic>7nAChR protein significantly increased （<italic>P<</italic>0.01）， the residence time of effective area in high dose group was prolonged （<italic>P<</italic>0.01）， the times of escape platform increased，and the contents of serum ACh，ChAT and hippocampal ACh，AchE，<italic>α</italic>7nAChR protein and <italic>α</italic>7nAChR mRNA increased （<italic>P<</italic>0.05）. Conclusion:Huanglian Jiedutang can significantly improve the learning and memory ability of AD rats induced by A<italic>β</italic>_1-42，and its mechanism may be related to the improvement of cholinergic system damage and enhancement of cholinergic system function induced by A<italic>β</italic>_1-42.

Fluid shear stress upregulated endothelial nitric oxide synthase gene expression and nitric oxide formation in human endothelial progenitor cells / 中华心血管病杂志

<p><b>OBJECTIVE</b>To observe the effect of fluid shear stress on the eNOS gene expression and NO production in endothelial progenitor cells (EPCs).</p><p><b>METHODS</b>The peripheral blood mononuclear cells from healthy volunteers were inducted into EPCs and divided into stationary group (0 dyn/cm(2), 1 dyn/cm(2) = 0.1 Pa), low-flow shear stress group (5 dyn/cm(2)), medium-flow shear stress group (15 dyn/cm(2)) and high-flow shear stress group (25 dyn/cm(2)). The effects of shear stress on the endothelial nitric oxide synthase (eNOS) gene expression and nitric oxide (NO) production in human EPCs were measured.</p><p><b>RESULTS</b>Typical "spindle-shaped" appearance was shown in EPCs derived from peripheral blood mononuclear cells and were positively labeled by acetylated-LDL, lectin, FLK-1 and vWF. After 4 hours treatment with various shear stresses, the ratio of eNOS/beta-actin mRNA expression by human EPCs in low, medium and high-flow shear stress group was 0.364, 0.505 and 0.548 respectively, which was significantly higher than that in stationary group (0.183, all P < 0.05) and the NO secretion in human EPCs in low, medium and high-flow shear stress group was also significantly higher than that in stationary group (all P < 0.05).</p><p><b>CONCLUSION</b>Fluid shear stress enhances the eNOS mRNA expression and NO secretion in human EPCs, therefore, shear stress could potentiate the repair efficacy of EPCs for endothelial injury.</p>

Increased brachial-ankle pulse wave velocity is associated with impaired endothelial function in patients with coronary artery disease / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Pulse wave velocity and flow-mediated vasodilation (FMD) are widely used as noninvasive modalities for evaluating atherosclerosis. However, it is not known whether pulse wave velocity is related to FMD in patients with coronary artery disease (CAD). Therefore, the present study was designed to investigate the alteration in brachial-ankle pulse wave velocity (baPWV) and endothelial function in CAD patients.</p><p><b>METHODS</b>Thirty-three patients with CAD and thirty control subjects were recruited for this study. baPWV was measured non-invasively using a VP 1000 automated PWV/ABI analyzer (PWV/ABI, Colin Co. Ltd., Komaki, Japan). Endothelial function as reflected by FMD in the brachial artery was assessed with a high-resolution ultrasound device.</p><p><b>RESULTS</b>baPWV was increased in CAD patients compared with control subjects [(1756.1 +/- 253.1) cm/s vs (1495.3 +/- 202.3) cm/s, P < 0.01]. FMD was significantly reduced in CAD patients compared with control subjects [(5.2 +/- 2.1)% vs (11.1 +/- 4.4)%, P < 0.01]. baPWV correlated with FMD (r = -0.68, P < 0.001). The endothelium-independent vasodilation induced by sublingual nitroglycerin in the brachial artery was similar in the CAD group compared with the control group.</p><p><b>CONCLUSIONS</b>CAD is associated with increased baPWV and endothelial dysfunction. Increased baPWV parallels diminished endothelial function. Our data therefore suggest that baPWV can be used as a noninvasive surrogate index in clinical evaluation of endothelial function.</p>

Fluid shear stress regulates secretion of tissue-type plasminogen activator in human endothelial progenitor cells / 中华心血管病杂志

<p><b>OBJECTIVE</b>In order to investigate the role of shear stress in the regulation of endothelial function, we assessed here effects of shear stress on tissue-type plasminogen activator in human endothelial progenitor cells (EPCs).</p><p><b>METHODS</b>The peripheral blood mononuclear cells were separated from healthy adult and inducted into EPCs, which were identified by double staining for the fluorescent labeled acetylated-LDL and lectin. EPCs were seeded on the small diameter artificial vessels, and then divided into four different experimental groups including stationary group, low-flow shear stress group (5 dyn/cm(2)), medium-flow shear stress group (15 dyn/cm(2)) and high-flow shear stress group (25 dyn/cm(2)). The levels of t-PA in EPC culture medium at 0 hour, 5 hours, 10 hours, 15 hours, 20 hours and 25 hours after culture were measured by enzyme-linked immunosorbent assay.</p><p><b>RESULTS</b>The peripheral blood mononuclear cells differentiated into EPCs after induction, which were positively labeled by fluorescent acetylated-LDL and lectin. Shear stress enhanced production of the t-PA by EPCs, which was paralleled to levels and times of shear stress.</p><p><b>CONCLUSIONS</b>Shear stress increases t-PA secretion by human EPCs, suggesting that shear stress not only regulates vascular endothelial function but also participates in the pathogenesis of arteriosclerosis.</p>

Change in endothelial progenitor cells and endothelial function in patients with unstable angina pectoris / 中华心血管病杂志

<p><b>OBJECTIVE</b>To investigate the relationship between endothelial progenitors cells (EPCs) and endothelium-dependent vasodilation in patients with unstable angina pectoris.</p><p><b>METHODS</b>Thirty patients with unstable angina pectoris (UAP) and thirty control subjects were recruited. Flow-mediated dilation (FMD) in the brachial artery was evaluated by using ultrasound Doppler flow method. The number of circulating EPCs was analyzed by flow cytometry analysis. Total mononuclear cells were isolated from peripheral blood by Ficoll density gradient centrifugation, and then the cells were plated on fibronectin-coated culture dishes. CD34 antigen of adherent cells was identified by immunohistochemical assay. EPCs were characterized as adherent cells double positive for FITC-UEA-I binding and DiI-acLDL uptake by direct fluorescent staining under inverted fluorescent microscope.</p><p><b>RESULTS</b>FMD was significantly impaired in the UAP group compared with the control group (5.93% +/- 2.67% vs 11.1% +/- 4.36%, P < 0.05). There was no significant difference in NMD between two groups (13.60% +/- 5.03% vs 14.18% +/- 4.50%, P > 0.05). The number of CD34(+) cells significantly increased in the UAP group compared with the control group (0.13% +/- 0.05% vs 0.09% +/- 0.04%, P < 0.05). There was a negative association between impaired FMD and increased CD34(+) cell (r = -0.385, P < 0.05). A positive antigen of CD34 of adhesion cells and double positive adhesion cells were found.</p><p><b>CONCLUSION</b>This study shows that the levels of peripheral CD34(+) cells in patients with UAP increase with an impaired endothelial function. The increase in EPCs may be an important compensatory response to acute coronary ischemia and impaired endothelium in patients with UAP.</p>

Tumor necrosis factor-alpha induces release of endothelial microparticles from human endothelial cells / 中华心血管病杂志

<p><b>OBJECTIVE</b>The present study was designed to investigate whether Tumor necrosis factor (TNF)-alpha stimulates release of endothelial microparticles (EMPs) by human endothelial cells, and whether EMPs may serve as a promising marker for endothelial injury and dysfunction.</p><p><b>METHODS</b>Human umbilical venous endothelial cells (HUVEC) were incubated with or without TNF-alpha for 24 hours at 37 degrees C. EMPs generated on the surface of HUVEC were observed with a scanning electron microscopy. The CD31 and CD51 positive EMPs in culture supernatants were measured by flow cytometer.</p><p><b>RESULTS</b>Fewer vesicles were observed on cell surface of control group, in TNF-alpha-stimulated one, however, cells manifested a blebby surface (eruption phenomenon) and more vesicles on surface were observed. The levels of EMPs were significantly increased in TNF-alpha stimulated cells compared with controls [CD31 + EMP, (164 +/- 63)/1000 cells vs. (42 +/- 10)/1000 cells, P < 0.05; CD51 + EMP, (260 +/- 108)/1000 cells vs. (19 +/- 4)/1000 cells, P < 0.05].</p><p><b>CONCLUSION</b>TNF-alpha can stimulate HUVEC to release EMPs which may serve as a surrogate marker for endothelial injury and dysfunction.</p>

A study of association between age-related circulating endothelial progenitor cells and arterial elasticity / 中华心血管病杂志

<p><b>OBJECTIVE</b>Reduced arterial elasticity is a hallmark of aging in healthy humans independently of diseases and endothelial-cell injury and dysfunction may be responsible for this fall in arterial elasticity. We hypothesized that circulating endothelial progenitor cells (EPCs) are involved in endothelial repair and that lack of EPCs contributes to impaired arterial elasticity.</p><p><b>METHODS</b>A total of 56 healthy male volunteers were divided into young (n = 26) and elderly (n = 30) groups. Large and small artery elasticity indices were non-invasively assessed by using pulse wave analysis. Flow cytometer was used to count the number of circulating CD34(+) mononuclear cells (MNCs), which were isolated from peripheral blood by Ficoll density gradient centrifugation, and then the cells were plated on fibronectin-coated culture dishes. EPCs were characterized as adherent cells double positive staining for DiI-acLDL uptake and lectin binding with using fluorescent microscope.</p><p><b>RESULTS</b>C(1) (large artery elasticity index) and C(2) (small artery elasticity index) were significantly reduced in the elderly group compared with those in the young group (11.73 +/- 1.45 vs 16.89 +/- 1.69 ml/mm Hg x 10, P < 0.001; 8.40 +/- 1.45 vs 10.58 +/- 1.18 ml/mm Hg x 100, P < 0.001 respectively). In parallel, the number of circulating EPCs was significantly reduced in the elderly group compared with the young group (0.13 +/- 0.02 vs 0.17 +/- 0.04%, P < 0.05). The number of circulating EPCs correlated with C(1) large and C(2) small artery elasticity indices (r = 0.47, P < 0.01; r = 0.4, P < 0.01). Fluorescent microscope was used to identify EPCs, which were double positive staining for DiI-acLDL uptake and lectin binding.</p><p><b>CONCLUSION</b>The present findings suggested that the fall in circulating EPCs with subsequently impaired endothelial-cell repair and function might contribute to reduced arterial elasticity in humans with aging. The decrease in circulating EPCs could serve as a surrogate biologic measure of vascular function and human age.</p>