基于生物量、活性物质积累和抗氧化能力的当归高海拔种植区域选择

目的以根茎生物量、活性物质含量以及抗氧化能力为指标,选择适宜提高当归品质的高海拔种植区域。方法在严格控制种质、水分和土壤养分的条件下,以不同海拔(2 100、2 500和2 900 m)2年生当归根茎为材料,分别对干质量、活性物质含量以及抗氧化能力进行测定与分析。结果高海拔虽不能促进当归根茎生物量,却显著提高了活性物质的积累量和抗氧化能力;以单株积累量计算,2 900 m未抽薹当归根茎中阿魏酸、可溶性糖、酚和黄酮类含量分别为2 100 m植株的2.06、1.13、1.34和1.15倍;体外抗氧化能力也随海拔升高逐渐增加。综合分析表明,在2 100～2 900 m海拔内,未抽薹当归根茎中活性物质的总积累量(干质量和单株)均随海拔升高逐渐增加。结论提升当归种植海拔高度可显著提高根茎活性物质量;活性物质生物合成与积累受到低温和光照的综合调控。该研究结果将为提高当归产量和品质以及大面积种植栽培提供理论基础与依据。     

厚朴超临界CO_2提取工艺优化及提取物抗氧化活性研究

目的优选超临界CO_2提取厚朴有效成分的工艺并探讨厚朴超临界CO_2提取物的抗氧化活性。方法采用HPLC法测定厚朴超临界CO_2提取物中厚朴酚与和厚朴酚的含量,正交试验优选厚朴超临界CO_2提取工艺,MTT法检测提取物抗氧化活性。结果厚朴酚优化工艺为萃取压力25 MPa,萃取温度55℃,CO_2用量30 kg;和厚朴酚最佳提取工艺压力15 MPa、萃取温度50℃、CO_2用量25 kg。厚朴超临界CO_2提取物具有抗氧化活性,且分离参数不同,抗氧化活性有显著差异。结论在所优选的提取工艺条件下,厚朴酚、和厚朴酚的提取效率较高,重复性较好,工艺稳定可行,提取物具有良好的抗氧化活性。     

人参皂苷抗肝纤维化作用机制研究进展

人参皂苷是一类重要的天然产物,在自然界中分布广泛,是多种药用植物中的主要活性成分,具有多种生理活性。研究发现,人参皂苷在肿瘤疾病治疗中取得很大进展,同时在抗肝纤维化方面也有显著的作用。因此人参皂苷对肝纤维化的治疗具有重要的应用价值。对人参皂苷的抗肝纤维化作用机制进行综述,以便为今后进一步的研究提供理论依据。     

野菊花总黄酮提取方法比较及其抗氧化活性研究

目的研究不同提取工艺的野菊花中总黄酮的量及其抗氧化活性。方法采用经典回流提取法、超声提取法、组织破碎提取法提取野菊花中黄酮类成分,以芦丁为对照品,通过紫外-可见分光光度法测定黄酮类成分的量,并用流动注射化学发光法测定野菊花中黄酮类成分的抗氧化活性。结果经典回流提取法、超声提取法、组织破碎提取法所提取的总黄酮的量分别为12.60、11.02、10.95 mg/g,采用流动注射化学发光法测得3种不同提取方法的总黄酮提取物的IC50分别是2.67、3.43、5.13μg/m L。结论经典回流提取法提取得到的野菊花总黄酮的量最高,且抗氧化活性最强,说明野菊花中总黄酮的量和抗氧化活性具有一致性。     

硫代葡萄糖苷及异硫氰酸酯的抗癌和抗氧化作用进展

目的为硫代葡萄糖苷及异硫氰酸酯的合理利用、功能性保健产品开发和抗癌辅助药物的研制提供依据。方法归纳总结近10年硫代葡萄糖苷和异硫氰酸酯的文献,对其在植物体的分布、理化性质、抗癌和抗氧化机制等方面进行详细阐述。结果硫代葡萄糖苷及其水解产物异硫氰酸酯具有良好的抗癌和抗氧化活性,可以预防和治疗多种癌症,对于由空气污染引发的呼吸系统及肺部疾病也具有良好的疗效;硫代葡萄糖苷及异硫氰酸酯可以清除血管和机体的自由基,保护心脑血管,延缓衰老。结论硫代葡萄糖苷及异硫氰酸酯开发成功能性保健产品和抗癌辅助药具有广阔的市场前景。     

虎杖苷对体外培养乳鼠心肌细胞肥大及成纤维细胞增殖的影响

目的研究虎杖苷对新生乳鼠离体培养心肌细胞和成纤维细胞增殖的影响及其抗氧化作用。方法剪取新生SD大鼠左心室,采用差速贴壁法分离并培养心肌细胞和成纤维细胞,将培养成功的成纤维细胞和心肌细胞均分为5组,即正常对照组、虎杖苷对照组(10-4mol/L)、模型组[10-6mol/L异丙肾上腺素(ISO)]、虎杖苷低浓度组(10-5mol/L+ISO 10-6mol/L)和虎杖苷高浓度组(10-4mol/L+ISO 10-6mol/L),进行相应干预。孵育2天后,采用考马斯亮兰法测定心肌细胞蛋白质含量,并测定其超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)活性;测定成纤维细胞增殖及其培养液中SOD和GSH-Px及NO浓度。结果与正常对照组比较,模型组可诱导心肌细胞蛋白含量增多,明显降低SOD及GSH-Px活力(P0.05);与模型组比较,虎杖苷高低浓度组心肌细胞蛋白含量明显降低,且SOD及GSH-Px活力明显升高(P0.05);虎杖苷高浓度对GSH-Px活性的升高明显较低浓度强,差异有统计学意义(P0.05)。与正常对照组比较,模型组可诱导成纤维细胞增殖,明显降低SOD及GSH-Px活力和NO含量(P0.05);与模型组比较,虎杖苷高浓度组能抑制成纤维细胞的增殖,显著升高NO含量和SOD及GSH-Px活力(P0.05)。结论虎杖苷对ISO诱导的乳鼠心肌细胞肥大和成纤维细胞增殖有一定对抗作用,其作用机制与其抗氧化作用以及影响NO生成有关。     

维生素E在体内外具有抗氧化作用

目的探讨维生素E在体内外的应激损伤。方法体外实验:人肝RBL细胞系根据H_2O_2损伤及损伤前后给予维生素E分为4组,对照组(C)、H_2O_2损伤组(Ec)、H_2O_2损伤前(Eb)及后(Ea)给维生素E组;体内实验:将20只清洁级雄性Wistar大鼠分为对照组和大及小剂量维生素E组,每天进行一次35和15 mg/kg溶液2 m L灌胃,连续3 d。体外实验应用MTT和TUNEL法检测细胞存活率和凋亡率,免疫印迹和免疫组化方法检测细胞中NF-κB、Hsp-70、Bcl-2、Bax及caspase-3的表达水平;体内实验应用生化法检测3和6 d后血浆内T-AOC、SOD、GSH和MDA的水平。结果 H_2O_2损伤组(Ec)细胞凋亡率增加(P0.01),细胞内Bax、Hsp-70、NF-κB及caspase-3显著升高(P0.01),而Bcl-2显著下降(P0.01),维生素E干预后能显著缓解上述变化(P0.01),H_2O_2损伤前干预效果优于后干预。灌胃后3 d血浆中T-AOC、SOD、GSH的水平增高,MDA降低(P0.01),6 d后其相关指标变化更加显著(P0.05)。结论维生素E可通过调节人肝RBL细胞相关蛋白表达水平和Wistar大鼠血浆中抗氧化酶体系而发挥抗氧化作用。     

HPLC-DAD法测定迷迭香茎和叶中11种抗氧化活性成分

目的建立HPLC-DAD同时测定迷迭香叶和茎中11种抗氧化活性成分含量的方法。方法采用Zorbax SB-Aq C18色谱柱(250 mm×4.6 mm,5μm);以甲醇(A)-磷酸二氢钾缓冲盐(B)溶液为流动相,梯度洗脱,体积流量1.0 mL/min,柱温30℃,绿原酸、咖啡酸、迷迭香酸、木犀草素、芹菜素和芫花素的检测波长为328 nm,丹皮酚、迷迭香酚、橙皮素、鼠尾草酚和鼠尾草酸的检测波长为284 nm,进样量10μL。结果绿原酸、咖啡酸、迷迭香酸、丹皮酚、迷迭香酚、橙皮素、木犀草素、芹菜素、鼠尾草酚、芫花素和鼠尾草酸分别在2.02~64.64μmol/mL,r=0.999 97;1.74~55.68μmol/mL,r=0.999 97;2.76~88.32μmol/mL,r=0.999 97;0.24~7.68μmol/mL,r=0.996 63;0.46~14.72μmol/mL,r=0.999 97;0.22~7.04μmol/mL,r=0.998 64;0.72~23.04μmol/mL,r=0.999 37;3.74~119.68μmol/mL,r=0.999 80;5.1~163.28μmol/mL,r=0.996 18;0.4~12.8μmol/mL,r=0.996 35;5.22~167.04μmol/mL,r=0.996 98内有良好的线性关系;平均加样回收率为98.1%~100.5%,RSD为0.67%~2.14%。结论该方法准确,实用性好,可用于迷迭香叶和茎中抗氧化活性成分的定性与定量分析。     

Endoscopic biopsy of islet transplants in the gastric submucosal space provides evidence of islet graft rejection in diabetic pigs

Transplantation of islets into the gastric submucosal space (GSMS) has several advantages (e.g., avoidance of the instant blood-mediated inflammatory response [IBMIR], ability to biopsy). The aim of this study was to determine whether endoscopic biopsy of islet allografts transplanted into the GSMS in diabetic pigs can provide histopathological and immunohistochemical information that correlates with the clinical course (e.g.,, blood glucose level, insulin requirement). Islet allografts (Group1: 10,000 kIEq /kg [n = 4]; Group2: 15,000 kIEq /kg [n = 2]) were transplanted into the GSMS of diabetic pigs under immunosuppression. In Group2, the anti-oxidant, BMX-001 was applied during preservation, isolation, and culture of the islets, and at the time of transplantation. Endoscopic biopsies of the islet grafts were obtained one or 2 weeks after transplantation, and histopathological features were compared with the clinical course (e.g., blood glucose, insulin requirement). In Group1, in the absence of anti-oxidant therapy, most of the islets became fragmented, and there was no reduction in exogenous insulin requirement. In Group2, with an increased number of transplanted islets in the presence of BMX-001, more healthy insulin-positive islet masses were obtained at biopsy and necropsy (4 weeks), and these correlated with reductions in both blood glucose level and insulin requirement. In all cases, inflammatory cell infiltrates were present. After islet transplantation into the GSMS, endoscopic biopsy can provide information on graft rejection, which would be an immense advantage in clinical islet transplantation.     

Role of renin-angiotensin system in liver diseases: an outline on the potential therapeutic points of intervention

Introduction: The current review aimed to outline the functions of the renin angiotensin system (RAS) in the context of the oxidative stress-associated liver disease.

Areas covered: Angiotensin II (Ang II) as the major effector peptide of the RAS is a pro-oxidant and fibrogenic cytokine. Mechanistically, NADPH oxidase (NOX) is a multicomponent enzyme complex that is able to generate reactive oxygen species (ROS) as a downstream signaling pathway of Ang II which is expressed in liver. Ang II has a detrimental role in the pathogenesis of chronic liver disease through possessing pro-oxidant, fibrogenic, and pro-inflammatory impact in the liver. The alternative axis (ACE2/Ang(1-7)/mas) of the RAS serves as an anti-inflammatory, antioxidant and anti-fibrotic component of the RAS.

Expert commentary: In summary, the use of alternative axis inhibitors accompanying with ACE2/ Ang(1-7)/mas axis activation is a promising new strategy serving as a novel therapeutic option to prevent and treat chronic liver diseases.