Endothelium-independent relaxation and contraction of rat aorta induced by ethyl acetate extract from leaves of Morus alba (L.)

Aim of the study

Based on screening for vasoactive traditional Chinese medicinal herbs, the present study was performed to investigate the vasoactive effects of an ethyl acetate extract from leaves of Morus alba (L.) (ELM) on rat thoracic aorta and the mechanisms underlying these effects.

Materials and methods

Isolated rat thoracic rings were mounted in an organ bath system and the effects of ELM on their responses were evaluated.

Results

ELM (0.125–32.000 g/l) induced a concentration-dependent relaxation (P < 0.01 vs. control) both in endothelium-intact and -denuded aortas precontracted by high K⁺ (6 × 10⁻² M) or 10⁻⁶ M phenylephrine (PE). In endothelium-denuded aortas, ELM at the EC₅₀ concentration reduced Ca²⁺-induced contraction (P < 0.01 vs. control) after PE or KCl had generated a stable contraction in Ca²⁺-free solution. And after incubation with verapamil, ELM induced contraction in endothelium-denuded aortas precontracted by PE (P < 0.01 vs. control); this was abolished by ruthenium red (P < 0.01 vs. ELM-treated endothelium-denuded group; P > 0.05 vs. control), but not by heparin (P > 0.01 vs. ELM-treated endothelium-denuded group; P < 0.01 vs. control).

Conclusions

The results showed that ELM had dual vasoactive effects, and the relaxation was greater than the contraction. The relaxation was mediated by inhibition of voltage- and receptor-dependent Ca²⁺ channels in vascular smooth muscle cells, while the contraction occurred via activation of ryanodine receptors in the sarcoplasmic reticulum.     

Astragaloside IV attenuates lipolysis and improves insulin resistance induced by TNFalpha in 3T3-L1 adipocytes

Increased circulating free fatty acid (FFA) concentrations have been demonstrated to potentially link obesity, insulin resistance and cardiovascular diseases. Astragaloside IV (AS-IV) is a saponin which is widely used in traditional Chinese medicine to treat type 2 diabetes and cardiovascular diseases. The purpose of the present study was to examine the effects of AS-IV on the lipolysis and insulin resistance induced by tumor necrosis factor-alpha (TNFalpha) in cultured 3T3-L1 adipocytes. TNFalpha promotes lipolysis in mammal adipocytes via the mitogen activated protein kinase (MAPK) family resulting in reduced expression/function of perilipin. Application of AS-IV inhibited TNFalpha-induced accelerated lipolysis in a dose-dependent manner, which was compatible with suppressed phosphorylation of ERK1/2 and reversed the downregulation of perilipin. Moreover, TNFalpha induced downregulation of key enzymes in lipogenesis, including LPL, FAS and GPAT, were also attenuated by AS-IV. Further studies showed that AS-IV improved TNFalpha-induced insulin resistance in 3T3-L1 adipocytes. This study provides the first direct evidence of the antilipolytic action of AS-IV in adipocytes, which may allow this agent to decrease the circulating FFA levels, thus increase insulin sensitivity and treat cardiovascular diseases.     

The best approach for early prediction of fetal gender by using free fetal DNA from maternal plasma

OBJECTIVES: Detection of free fetal DNA (ffDNA) in maternal blood during pregnancy has given rise to the possibility of developing new noninvasive approaches for early prenatal diagnosis.On a large-scale study, two protocols of real-time polymerase chain reaction (PCR) were compared in order to establish which Y-specific locus, either multicopy DYS14 or single copy SRY sequence, was the most suitable for developing a test with high diagnostic efficiency for early fetal gender assessment. The second aim was to assess whether the combination of the two detection systems could increase the performance of the prenatal test. METHODS: We analyzed 145 plasma samples from healthy pregnant women between 11 and 12 weeks of singleton gestation. For each sample, fetal gender was determined by using both protocols (DYS14 and SRY) during the same real-time PCR run. RESULTS: The data obtained by the DYS14 and SRY assays showed an efficiency in fetal gender prediction of 97.9 and 80%, respectively. It is not advisable to combine the two protocols because this association does not help in further improvements in fetal gender prediction. CONCLUSIONS: DYS14 assay is the best approach for early fetal gender assessment because it is more sensitive, accurate, and efficient than the SRY assay.     

子宫内膜异位症患者腹腔液中正常T淋巴细胞表达和分泌调节活化因子水平的变化及意义

目的 探讨子宫内膜异位症(内异症)患者腹腔液中正常T淋巴细胞表达和分泌调节活化因子(RANTES)分泌水平的变化及其对单核巨噬细胞趋化的影响.方法 建立内异症异位病灶主要细胞--子宫内膜基质细胞(ESC)、腹膜间皮细胞(HPMC)及单核巨噬细胞系U937不同组合的直接接触(E-H-U、E-H、E-U、H-U)及间接接触共培养体系(U/E-H、H/E-U、E/H-U),然后收集共培养上清液,用酶联免疫吸附试验(ELISA)检测RANTES分泌水平的变化.利用趋化实验观察ESC、HPMC及ESC-HPMC共培养对单核巨噬细胞的趋化作用.结果 ESC、HPMC、U937单独培养时,RANTES的分泌水平分别为(5.0±0.5)、(4.0±0.3)、(254±40)ng/L;与单独培养比较,共培养明显促进RANTES的分泌,其中E-H-U培养为(2250±96) ng/L,E-U培养为(243±192) ng/L,H-U培养为(1251±73) ng/L,E-H培养为(50±40) ng/L,3种细胞直接共培养较两种细胞直接共培养时,RANTES分泌水平明显升高,差异有统计学意义(P＜0.01);间接共培养时,RANTES的分泌水平分别为(1519±96) ng/L(E/H-U培养)、(912±93) ng/L(U/E-H培养)、(1201±93)ng/L(H/E-U培养).ESC、HPMC及ESC-HPMC共培养可促进单核巨噬细胞的趋化,迁移细胞数分别为(6.0±0.3)、(6.2±0.3)、(10.0±0.3)×103个.结论 内异症病灶主要细胞间存在着复杂的相互作用机制,并可促进趋化因子RANTES的分泌,从而促进腹腔内单核巨噬细胞的趋化和募集.     

细胞周期调控基因p21和p27单核苷酸多态性与卵巢上皮性癌的关系

目的 探讨细胞周期调控基因p21和p27的单核苷酸多态性(SNP)与卵巢上皮性癌(卵巢癌)发病风险的关系.方法 采用聚合酶链反应-限制性片段长度多态性(PCR-RFLP)方法检测234例卵巢癌患者(卵巢癌组)和284例健康妇女(对照组)p21基因C/T和p27基因V/G SNP位点基因型和等位基因的频率分布.结果 (1)对照组妇女p21基因的C/C、C/T和T/T基因型频率分别为34.2%、49.6%和16.2%,C和T等位基因频率分别为59.0%和41.0%;卵巢癌组患者3种基因型频率分别为28.2%、53.0%和18.8%,C和T等位基因频率分别为54.7%和45.3%.两组基因型频率和等位基因频率分别比较,差异均无统计学意义(P＞0.05).3种基因型频率在4种病理类型的卵巢癌中的分布有明显差异(P=0.02),C/C基因型降低子宫内膜样癌的发病风险(OR为0.56,95%CI为0.32～0.98).(2)对照组妇女p27基因V/V、V/G和G/G基因型频率分别为88.4%、10.9%租0.7%,V和G等位基因频率分别为93.8%和6.2%;卵巢癌组患者的基因型频率分别为93.6%、5.1%和1.3%,V和G等位基因频率分别为96.2%和3.8%.两组基因型频率分布比较,差异有统计学意义(P=0.04),等位基因频率分布比较,差异则无统计学意义(P=0.09).与V/G和G/G基因型比较,V/V基因型增加卵巢癌的发病风险(OR为1.92,95%CI为1.02～3.63).结论 p21基因C/T多态性的C/C基因型可能降低子宫内膜样癌的发病风险,p27基因的V/V基因型可能是卵巢癌发病的潜在危险因素.