桃胶多糖的制备、质量表征及利尿作用研究

采用水提醇沉法制备桃胶多糖,DNS法测定总多糖含量,红外光谱法建立化学指纹图谱,漏斗法收集尿液,测定生理盐水负荷的小鼠给药4 h尿量,测定尿液中Na^+、K^+、Cl^-含量和肾脏组织Na^+-K^+-ATP酶的活力.制备得到多糖纯度较高,含量为96. 30%,红外光谱显示多糖特征信号.桃胶多糖的利尿作用评价结果显示,与空白组比较,高、中、低剂量组均可明显增加小鼠的排尿量,且桃胶多糖高剂量组对小鼠尿排出量作用较为均匀持久;同时,桃胶多糖可增加尿液中Na^+的含量,对Cl^-含量无明显影响,Na^+/K^+值与空白组无显著差异,对肾脏组织Na^+-K^+-ATP酶活力的测定结果表明桃胶多糖对Na^+-K^+-ATP酶没有显著影响.桃胶多糖具有明显的利尿作用,且不引起电解质发生紊乱,是具有较好利尿功能的中药提取物.

复方竹节参颗粒对缩宫素诱导的原发性痛经的影响

目的探讨复方竹节参颗粒对缩宫素诱导的原发性痛经的影响。方法将KM小鼠、SD大鼠分别随机分为空白组、模型组、痛经宝阳性对照组(小鼠4.11 g/kg、大鼠1.87 g/kg)、复方竹节参颗粒组[低剂量组(小鼠6.17 g/kg、大鼠2.80 g/kg),高剂量组(小鼠18.5 g/kg、大鼠8.41 g/kg)],采用己烯雌酚(小鼠10~20 mg/kg,大鼠5~10 mg/kg)和缩宫素(小鼠20 U/kg,大鼠10 U/kg)诱导原发痛经动物模型,观察记录各组鼠的痛经表观指标(行为反应、饮食、精神状态、毛色、被毛光泽度)并进行评分,采用扭体法观察各组鼠的扭体潜伏期、扭体次数,检测给组鼠血清生化指标(PGE2、NO、MDA)水平。取己烯雌酚诱导后的大鼠子宫,离体加入缩宫素(5 U/L),15 min后加入复方竹节参颗粒(90、270 mg/L),采用PowerLab生物信号记录系统记录体外子宫平滑肌收缩张力曲线,计算收缩张力抑制率。结果与模型组比较,复方竹节参颗粒低剂量(常规剂量)组能延长扭体潜伏期,减少扭体次数(P<0.01),升高PGE2、NO水平(P<0.01),降低MDA水平(P<0.01),提高子宫平滑肌收缩张力抑制率(P<0.01)。结论复方竹节参颗粒具有较好的抗痛经作用,并且在常规剂量使用时疗效更好,可为客观评价其药效作用提供了科学依据。

基于抑菌效应成分指纹谱的黄芩质量评价研究

化学指纹图谱是中药质控的重要手段,但常规指纹图谱存在冗余信息,影响了其准确性和可用性,需要进行改进和提升。本研究采用量反应平行线法原理检测黄芩抑菌活性生物效价;采用HPLC法检测不同黄芩样品的化学指纹图谱;采用灰色关联法(GRA)辨识主要抑菌效应成分。结果表明,15批黄芩样品抑菌效价在0~1000 U·g^-1,平均抑菌效价为556.29±258.57 U·g^-1(1 U约相当于2.25μg庆大霉素的抑菌活性);15批黄芩样品的HPLC指纹图谱中共标定34个特征峰,样品间相似度为0.255~0.991;取灰色关联序前10位成分且与抑菌效价成正相关的P33、P30(黄芩素)、P19(黄芩苷)、P15、P29、P34、P31(汉黄芩素)、P28的8个成分并赋予权重,建立黄芩效应成分指纹谱,能够明确区分黄芩各规格等级样品,并能综合表征黄芩性状、成分、抑菌效价差异。综之,本研究构建了直接关切黄芩抑菌活性且信息简化的抑菌效应成分指纹谱,可综合评价黄芩质量,提高了中药指纹图谱的功效专属性和质量辨识能力,并可为其他中药质量综合评价提供有益参考。

香薷挥发油纳米乳喷雾的制备及其抗菌活性的研究

香薷是常用芳香中药,挥发油类成分是其主要药效成分,具有广谱抗菌抗病毒作用,但香薷挥发油具有一定刺激性和不稳定性,需要制备为特定剂型以供使用。该文采用水蒸气蒸馏法提取香薷挥发油,采用HPLC测定其中麝香草酚和香荆芥酚的质量浓度分别为(0.111 9±0.001 0)、(0.235 4±0.004 7) mg·mL^(-1);采用伪三元相图法和表面活性剂复配法,筛选最适辅料(表面活性剂与助表面活性剂),制备得到香薷挥发油纳米乳,继而载入压力容器得到喷雾剂,并对其稳定性和抗菌活性进行评价。以澄明度、黏度、气味、体感等为综合指标,最终确定纳米乳的优选处方为香薷挥发油-薄荷油-cremophor EL-无水乙醇-蒸馏水7.78∶1.58∶19.26∶6.15∶65.23,制得的香薷挥发油纳米乳为淡黄色透明液体,经平行光照射能产生丁达尔现象,测得其pH为5.50,电导率为125.9μS·cm^(-1),平均粒径为15.45 nm,多分散系数(PDI)为0.156,Zeta电位为-17.9 mV;在透射电镜下纳米粒子呈规则球形,相互之间并无粘黏团聚现象。稳定性考察结果表明,香薷挥发油纳米乳在4~55℃稳定性良好,且30 d内并未出现破乳分层的现象;将香薷挥发油纳米乳以12 000 r·min^(-1)离心30 min,无分层现象。制得香薷挥发油纳米乳对金黄色葡萄球菌标准菌株、金黄色葡萄球菌耐药菌株及大肠杆菌标准菌株均有良好的抑制作用,最低抑菌质量浓度分别为0.39、3.12、1.56 mg·mL^(-1)。以上结果表明所制得的香薷挥发油纳米乳工艺可行、理化性质稳定、具有良好的抗菌作用,为香薷挥发油的防疫防感产品的开发提供了可行的技术方案。

Dandelion polyphenols protect against acetaminophen-induced hepatotoxicity in mice via activation of the Nrf-2/HO-1 pathway and inhibition of the JNK signaling pathway

We investigated the liver protective activity of dandelion polyphenols(DP)against acetaminophen(APAP;Paracetamol)-induced hepatotoxicity.Mice were acclimated for 1 week and randomly divided into the following groups(n=9 per group):Control,APAP,APAP+DP(100 mg·kg^–1),APAP+DP(200 mg·kg^–1),and APAP+DP(400 mg·kg^–1)groups.Mice were pretreated with DP(100,200,and 400 mg·kg^–1)by oral gavage for 7 d before being treated with 350 mg·kg^–1 APAP for 24 h to induced hepatotoxicity.Severe liver injury was observed,and hepatotoxicity was analyzed after 24 h by evaluation of biochemical markers,protein expressions levels,and liver histopathology.Pretreatment with DP was able to restore serum liver characteristics(aspartate transaminase,AST;alanine aminotransferase,ALT;alkaline phosphatase,AKP),improve redox imbalance(superoxide dismutase,SOD;glutathione,GSH;malondialdehyde,MDA),and decrease inflammatory factors(tumor necrosis factor-α,TNF-α;interleukin-1β,IL-1β).Pretreatment with DP also significantly inhibited the expression levels of nitric oxide synthase(iNOS)and cyclooxygenase-2(COX-2).Furthermore,DP pretreatment could inhibit the apoptosis of liver cells caused by APAP through up-regulation of Bcl-2 and down-regulation of Bax and caspase-9 protein.DP also down-regulated p-JNK protein expression levels to inhibit APAP-induced mitochondrial oxidative stress and up-regulated the expression of Nrf-2 and its target gene HO-1.The histopathological staining demonstrated that DP pretreatment could inhibit APAP-induced hepatocyte infiltration,congestion,and necrosis.Our results demonstrate that DP pretreatment could protect against APAP-induced hepatic injury by activating the Nrf-2/HO-1 pathway and inhibition of the intrinsic apoptosis pathway.

Protective Effect of Fresh/Dry Dandelion Extracts on APAP-Overdose-Induced Acute Liver Injury

Objecitvie:To compare the liver protective activity of fresh/dried dandelion extracts against acetaminophen(APAP)-induced hepatotoxicity.Methods:Totally 90 Kunming mice were randomly divided into10 groups according to body weight(9 mice for each group).The mice in the normal control and model(vehicle control)groups were administered sodium carboxymethyl cellulose(CMC-Na,0.5%)only.Administration groups were pretreated with high and low-dose dry dandelion extract(1,000 or 500 g fresh herb dried and then decocted into 120 mL solution,DDE-H and DDE-L);low-,medium-and high-dose dandelion juice(250,500,1,000 g/120 mL,DJ-L,DJ-M,and DJ-H);fresh dandelions evaporation juice water(120 mL,DEJW);dry dandelion extract dissolved by pure water(1 kg/120 mL,DDED-PW);dry dandelion extract dissolved by DEJW(120 g/120 mL,DDED-DEJW)by oral gavage for 7 days at the dosage of 0.5 mL solution/10 g body weight;after that,except normal control group,all other groups were intraperitonealy injected with 350 mg/kg APAP to induce liver injury.Twenty hours after APAP administration,serum and liver tissue were collected and serum alanine aminotransferase(AST),aspartate transaminase(ALT),alkaline phosphatase(AKP),malondialdehyde(MDA),glutathione(GSH),superoxide dismutase(SOD)activities were quantified by biochemical kits;tumor necrosis factor(TNF-α),interleukin(IL)-2,and IL-1β contents in liver tissue were determined by enzyme linked immunosorbent assay kits.Histopathological changes in liver tissues were observed by hematoxylin and eosin staining;TUNEL Assay and Hoechst 33258 staining were applied for cell apoptosis evaluation.The expressions of heme oxygenase-1(HO-1),nuclear factor erythroid-2-related factor 2(Nrf-2),caspase-9,B-cell leukemia/lymphoma 2(Bcl-2),Bax and p-JNK were determined by Western blot analysis.Results:Pretreatment with fresh dandelion juice(FDJ,including DJ-L,DJ-M,DJ-H,DEJW and DDED-DEJW)significantly decreased the levels of serum ALT,AST,AKP,TNF-α and IL-1β compared with vehicle control group(P<0.05 or P<0.01).Additionally,compared with the vehicle control group,FDJ decreased the levels of hepatic MDA and restored GSH levels and SOD activity in livers(P<0.05 or P<0.01).FDJ inhibited the overexpression of pro-inflammatory factors including cyclooxygenase-2 and inducible nitric oxide synthase in the liver tissues(P<0.05 or P<0.01).Furthermore,Western blot analysis revealed that FDJ pretreatment inhibited activation of apoptotic signaling pathways via decreasing of Bax,and caspase-9 and JNK protein expression,and inhibited activation of JNK pathway(P<0.05 or P<0.01).Liver histopathological observation provided further evidence that FDJ pretreatment significantly inhibited APAP-induced hepatocyte necrosis,inflammatory cell infiltration and congestion.Conclusions:FDJ pretreatment protects against APAP-induced hepatic injury by activating the Nrf-2/HO-1 pathway and inhibition of the intrinsic apoptosis pathway,and the effect of fresh dandelion extracts was superior to dried dandelion extracts in APAP hepatotoxicity model mice.