Ameliorative effect of Eucommia ulmoides Oliv. leaves extract (ELE) on insulin resistance and abnormal perivascular innervation in fructose-drinking rats

Aim of the study

Eucommia ulmoides Oliv. leaf is a traditional Chinese medicine that exhibits an anti-diabetic action. This study was designed to investigate whether long-term administration of Eucommia ulmoides Oliv. leaves extract (ELE) ameliorates pre-diabetic state of insulin resistance and abnormal perivascular innervation in the hyperinsulinemic state.

Materials and methods

ELE at doses of 500 and 1000 mg/kg was administered orally once daily for 4 weeks in fructose-drinking rats (FDRs). Plasma levels of insulin, blood glucose levels, and perivascular innervation were assessed using biochemical and immunohistochemical methods.

Results

FDR showed significant increase in plasma levels of insulin, an index for insulin resistance (Homeostasis Model Assessment ratio—HOMA-IR) and systolic blood pressure (SBP), but not blood glucose levels, as compared with control rats. Immunohistochemical study showed significantly greater density of tyrosine hydroxylase (TH)-like immunoreactivity (LI)-containing nerves and significantly lower density of calcitonin gene-related peptide (CGRP)-LI-containing nerves in mesenteric arteries of FDR than those in control. A 4-week treatment with ELE (500 and 1000 mg/kg, p.o.) significantly decreased plasma levels of insulin and HOMA-IR without affecting blood glucose levels and significantly lowered SBP in FDR. ELE treatment in FDR resulted in significant increase in CGRP-LI never fiber density and significant decrease in TH-LI never fiber density in mesenteric arteries of FDR.

Conclusions

These results suggest that long-term ELE treatment effectively prevents insulin resistance development and ameliorates abnormal perivascular innervation in FDR.     

杜仲对UVA致HaCaT细胞光老化保护作用的实验研究

目的：研究杜仲不同提取部位抗UVA致HaCaT细胞光老化的作用,并初步探讨其作用机制。方法：杜仲乙醇提取物经大孔树脂制备不同浓度乙醇梯度洗脱部位,分别作用于HaCaT细胞光老化模型,倒置显微镜下观察细胞形态,MTT法测定细胞活性,测定细胞培养液中LDH、MDA、SOD活力,确定并筛选杜仲抗皮肤光老化的作用及有效部位。结果：与模型组相比,浓度为1255μg/ml的50%乙醇大孔树脂洗脱部位能提高细胞活性（P〈0.05）,使培养液中LDH降低（P〈0.01）、SOD活力提高（P〈0.05）、MDA活力降低（P〈0.05）;浓度为125μg/ml的水洗脱部位使细胞培养液中LDH活力降低（P〈0.05）。结论：杜仲抗皮肤光老化作用的有效成分主要集中在50%乙醇大孔树脂洗脱部位,其作用机制可能与其能清除氧自由基、保护细胞膜免受损伤有关。     

杜仲胶复合义齿软衬材料的研制及细胞毒性检测

目的 利用杜仲胶的优良特性,制备高弹性杜仲胶复合义齿软衬材料,检测其相关物理学性能和细胞毒性,探讨用于临床的可能性。方法 参考现有弹性杜仲胶配方和医用橡胶配方,以硬度、拉伸强度和断裂伸长率为力学性能观察指标,确定材料各主要成分的种类和用量,制备杜仲胶复合义齿软衬材料。应用四甲基偶氮唑蓝（MTT）方法,检测和比较各组杜仲胶复合义齿软衬材料、丙烯酸自凝软衬材料和Silagum硅橡胶义齿软衬材料的50%浸提液对体外培养细胞L929的毒性作用,采用SPSS 16.0软件包对数据进行统计学分析。结果 橡胶基质的种类和加入共混比例对杜仲胶复合义齿软衬材料的力学性能有显著影响,加入杜仲胶显著提高了顺丁橡胶的生胶强度,硬度、拉伸强度和断裂伸长率随之升高。MTT检测结果显示,各组杜仲胶复合义齿软衬材料对L929细胞无毒性,与丙烯酸自凝软衬材料和Silagum硅橡胶义齿软衬材料相比,5组杜仲胶复合义齿软衬材料在2、4、7 d时的毒性级别基本维持在1级,仅70:30组在7 d时达到2级。Silagum硅橡胶软衬材料和各组杜仲胶复合义齿软衬材料在2、4、7 d时的细胞相对增殖率均显著高于同等条件下的丙烯酸自凝软衬材料（P<0.05）。结论 杜仲胶与顺丁橡胶共混比例为70:30时,适量添加氧化锌、氧化镁、硬脂酸、升华硫、促进剂CZ、防老剂,可制备出力学性能适宜的高弹性杜仲胶复合义齿软衬材料。杜仲胶复合义齿软衬材料对体外培养的小鼠成纤维细胞L929无毒性,初步认为其生物相容性良好。     

补肾壮骨颗粒增强骨密度作用的动物实验研究

目的比较低钙、CaCO3及补肾壮骨颗粒对大鼠股骨生长的影响,进行补肾壮骨颗粒增加骨密度的作用研究。方法70只清洁级SD雌性大鼠,分设3个剂量的受试组、相应的CaCO3对照组和低钙对照组,喂养90 d后,测定各组大鼠的股骨干重、密度、钙表观吸收率及骨钙含量等指标。结果3.30,6.60 g/kg.bw剂量受试组的股骨钙含量与钙总量、中点和远心端密度均高于低钙组(P<0.05或P<0.01);1.65,6.60 g/kg.bw剂量受试组的股骨钙总量和远心端密度分别高于相应CaCO3组(P<0.05或P0.05)。结论补肾壮骨颗粒的钙吸收率较高,并具有增加骨密度的功能作用。     

杜仲扦插繁殖技术研究

通过杜仲的扦插繁殖试验，结果认为：在北京地区最适宜的扦插期是5月下旬至7月中旬；成年树插穗的成活率很低，一般在20％以下，2年生幼树插穗成话率可达60％；外源生长素对诱发插穗不定根生长效果显著，其中NAA50μg／mL处理20年生成树的当年生枝条，最高成活率可达68％，根系生长茂密。     

杜仲提取物的亚慢性毒理学研究

目的研究不同剂量的杜仲提取物水溶液对小鼠亚慢性毒性作用,为临床应用提供依据。方法给实验小鼠灌服不同剂量的杜仲提取物水溶液。在实验中、末期停药后24 h,分别取血测定血液学、血液生化和主要脏器指标,并作病理切片。结果灌胃中、低剂量(2.06 g/kg,0.69 g/kg)的杜仲提取物水溶液,能够提高小鼠血红蛋白含量和红细胞数(P<0.01),对白细胞分类计数无影响,同时能够提高小鼠体重、总蛋白及白蛋白含量(P<0.01),对脾脏、肝脏、心脏、肺脏、肾、性器官指数及血清酶活性无影响(P>0.05)。结论杜仲提取物对受试动物未见有明显毒性作用。     

杜仲雄花水提液治疗特应性皮炎的实验研究

目的观察杜仲雄花水提液对IgE介导的小鼠皮炎动物模型的作用。方法以2,4-二硝基氯苯(DNCB)诱导小鼠特应性皮炎为动物模型,研究杜仲雄花茶水提液对其血清某些细胞因子IL-4、IFN-γ及IgE水平的影响。结果杜仲雄花水提液可抑制血清IgE及血清IL-4产生,上调IFN-γ。结论杜仲雄花茶水提液对特应性皮炎具有抗炎、抗过敏作用。     

Studies on Resin Purification Process Optimization of Eucommia Ulmoides Oliver and Its Antihypertensive Effect Mechanism

Background

Through research it is found that the barks, stems, fruits and flowers of Eucommia ulmoides contain various compositions, such as lignin, cycloalkane and phenylpropanoids. The modern pharmacological research shows that Eucommia ulmoides has many functions, such as anti-aging, antitumor and bone cell proliferation. This paper studied the resin purification process optimization conditions and antihypertensive effect of Eucommia ulmoides Oliver.

Materials and Methods

The orthogonal experiment method was adopted to determine the purification effect of various macro-porous resins for eucommia ulmoides Oliver, and the SHR model was used to determine antihypertensive level of eucommia ulmoides Oliver.

Results

The optimal process of resin extraction and purification of Eucommia ulmoides Oliver was verified through the loading liquid concentration at 6 mg/ml, 20% ethanol used as the eluent; the flow rate control was 3.0, column volume per hour and the diameter-height ratio of adsorption column was 1:6; the extracts of Eucommia ulmoides Oliver can reduce SHR blood pressure, its antihypertensive effect is relatively stable and has no significant impact on HR, but the antihypertensive effect is lower than that of control medicine captopril. Also, the extracts of eucommia ulmoides Oliver can significantly increase the content of serum NO and reduce the content of ET.

Conclusion

The Eucommia ulmoides Oliver can relax blood vessels, reduce the peripheral resistance, reduce the returned blood volume, and eventually achieve the antihypertensive effect.     

杜仲叶提取物对腹部脂肪蓄积抑制作用的研究

目的 探讨杜仲叶提取物对人体内腹部脂肪蓄积的抑制作用.方法 将27例腹型肥胖患者随机分为2组(试验组15例,对照组12例),分别口服杜仲胶囊(含杜仲叶提取物)及安慰剂胶囊,第8周末观察每组患者体重、腹围、体重指数(BMI)、皮下脂肪及内脏脂肪的变化.结果 试验组与对照组比较,内脏脂肪及皮下脂肪明显减少(P＜0.05),...     

杜仲绿原酸通过PI3K/AKT/Nrf-2通路增强视网膜母细胞瘤细胞系HXO-Rb44放射敏感性

目的　探究杜仲绿原酸（CGA）通过调控PI3K/AKT/Nrf-2通路,对视网膜母细胞瘤细胞系HXO-Rb44放射敏感性的增强作用。 方法　通过不同浓度的CGA处理HXO-Rb44细胞,检测IC10,作为后续实验中CGA浓度。将细胞分为Ctrl、Radio、CGA、Radio+CGA组,Radio组给予4 MV X射线照射24 h,CGA组使用CGA处理24 h,Radio+CGA组在CGA处理24 h后再给予4 MV X射线照射24 h,流式细胞术检测细胞周期与细胞凋亡,蛋白质印迹检测Ki67、依赖还原型辅酶I/II醌氧化还原酶I（NQO1）、活化型半胱天冬酶（cl-caspase-3）、硫氧还蛋白还原酶1（TrxR1）、活化磷脂酰肌醇3-激酶（p-PI3K）、蛋白激酶B（AKT）、p-AKT、核因子E2相关因子2（Nrf2）蛋白表达。进一步通过PI3K激活剂740Y-P处理细胞,检测细胞周期、凋亡、增殖和相关蛋白表达、PI3K/AKT/Nrf2通路蛋白表达。 结果　随着CGA浓度的增高,细胞的相对存活率降低,药物毒性呈浓度依赖性,IC10为81.59 μmol/L。与Ctrl组相比,Radio和CGA组G2/M期细胞比例显著升高,细胞凋亡比率显著升高（P<0.01）;与Radio组相比,Radio+CGA组G2/M期细胞比例和细胞凋亡比率进一步显著升高（P<0.01）。同时在蛋白水平上,与Ctrl组相比,Radio和CGA组Ki67、NQO1、TrxR1、p-PI3K、Nrf2蛋白表达及p-AKT/AKT比率显著降低（P<0.01）;放射和CGA联合作用进一步降低以上各指标（P<0.01）。此外,PI3K激活剂可逆转放射对细胞周期、增殖、凋亡以及PI3K/AKT/Nrf2通路的作用,CGA可恢复放射引起的上述各指标的变化（P<0.01）。 结论　CGA可增强HXO-Rb44细胞的放射敏感性,其作用机制与抑制PI3K/AKT/Nrf2通路相关。