黄芩有效成分对四氯化碳致伤的原代培养大鼠肝细胞的作用

作者采用原代培养大鼠肝细胞研究黄芩有效成分的护肝作用，并对其中含量较多的结晶单体进行结构鉴定。结果表明：黄芩的乙酸乙酯萃取物和正丁醇萃取物（１．０～２．５ｍｇ／ｍｌ）均可使四氯化碳致伤的肝细胞培养液中ＡＬＴ活性显著降低（Ｐ＜０．００１）。从黄芩乙酸乙酯萃取物分离出来的晶Ⅱ、Ⅲ、Ⅳ在所试浓度下均有显著护肝作用；晶Ⅰ则主要为直接抑制酶活性作用。经理化鉴别和光谱分析，晶Ⅰ、Ⅱ分别为汉黄芩素和黄芩素。     

黄芩素对喉癌Hep-2细胞增殖的抑制作用

目的：探讨黄芩素对人喉癌Hep-2细胞的增殖抑制作用。方法：Hep-2细胞在含黄芩素（10~80μmol/L）的培养基中,分别培养24 h及48 h,用MTT法检测对细胞增殖的影响;用台盼兰染色法检测对细胞活力的影响;用吖啶橙染色法（AO染色法）检测对细胞形态的影响。结果：黄芩素呈时间-剂量依赖性的抑制Hep-2细胞的增殖,并可使细胞活力明显降低;AO染色法显示,黄芩素可诱导Hep-2细胞形态发生明显变化,呈凋亡形态。结论：黄芩素可抑制喉癌Hep-2细胞增殖,降低细胞活力,诱导喉癌Hep-2细胞呈典型的凋亡形态。     

HPLC法同时测定双黄连胶囊中黄芩苷、黄芩素的含量

目的：建立反相高效液相色谱法同时测定双黄连胶囊中黄芩苷、黄芩素的含量。方法：采用Agilent Eclipse XDB-C18（250 mm×4.6 mm,5μm）色谱柱,以甲醇-0.1%磷酸溶液为流动相梯度洗脱,检测波长为277 nm,流速为1.0 ml/min,进样量为10μl,柱温为30℃。结果：黄芩苷在6.072～151.800μg/ml范围内有良好的线性关系,r=1.000 0（n=7）;黄芩素在2.124～53.100μg/ml范围内有良好的线性关系,r=0.999 4（n=7）。黄芩苷的平均回收率为99.21%,RSD为0.5%（n=6）;黄芩素的平均回收率为99.12%,RSD为0.6%（n=6）。结论：本法操作简便、快速、结果准确,可用于双黄连胶囊的质量控制。     

高效液相色谱法测定固经丸中黄芩苷含量

目的建立高效液相色谱法测定固经丸中黄芩苷含量的方法。方法采用高效液相色谱法。YWG-NH2分析色谱柱(4.6mmID×250mm,粒径5μm)。流动相乙腈-水(26∶74,含5ml三乙胺,磷酸调pH2.6),流速1.0ml/min,检测波长276nm。结果黄芩苷的理论板数为2950,黄芩苷回归方程y=796121.5x 621926.0,r=0.9999,线性范围20.20~202.0μg/ml。其回收率为100.5%(n=6),RSD2.1%。结论该方法操作简便,结果准确。     

黄芩素对肝癌HepG2细胞增殖和凋亡的影响及miR-34a在其机制中的作用

目的:观察12-脂氧合酶抑制剂黄芩素(Baicalein)对人肝癌细胞株HepG2增殖和凋亡的影响,并初步研究miR-34a在黄芩素影响HepG2细胞机制中的作用.方法:黄芩素(浓度分别为25、50和100 μmol/L)作用HepG2细胞24 h和48 h后,分别用Hoechst33342染色后荧光显微镜观察HepG...     

高效液相色谱法测定复方鱼腥草颗粒中黄芩苷和黄芩素含量

目的 建立同时测定复方鱼腥草颗粒中黄芩苷和黄芩素含量的方法。方法 采用高效液相色谱法,以Thermo-C18（4.6 mm×250 mm,5 μm）为色谱柱,以乙腈-0.1%甲酸溶液为流动相,进行梯度洗脱,流速为1.0 mL/min,进样量为10 μL,检测波长为274 nm,柱温为25 ℃。结果 可在30 min内完成对黄芩苷和黄芩素的色谱分析,测得的黄芩苷的线性范围为0.069～0.34 mg/mL,r=0.999 8,平均回收率为99.5%（RSD=3.33%）;黄芩素的线性范围为0.005～0.025 mg/mL,r=0.999 4,平均回收率为102.7%（RSD=2.44%）。结论 所建立的高效液相色谱法方便快捷、准确、简便、重复性好,可用于复方鱼腥草颗粒的质量控制。     

黄芩素抑制宫颈癌HeLa细胞迁移作用机制的研究

目的：观察不同浓度黄芩素干预宫颈癌HeLa细胞后,细胞迁移、细胞培养基中基质金属蛋白酶2（matrix metalloproteinase 2,MMP2）、基质金属蛋白酶9（matrix metalloproteinase,MMP9）活性的变化,以及MMP2、MMP9 mRNA和蛋白表达水平的变化。方法：体外培养宫颈癌HeLa细胞,分空白对照（Control）组、50、100、200、300μmol/L干预组,培养12、24、48 h。镜下观察细胞形态及数量的变化;流式细胞技术法检测细胞周期的变化;细胞迁移实验观察细胞迁移的改变;明胶酶谱法检测细胞培养基中的MMP2、MMP9活性变化;RT-PCR检测MMP2、MMP9 mRNA表达水平的变化;Western Bloting检测MMP2、MMP9蛋白表达水平的变化。结果：黄芩素干预24 h后,与空白对照组相比较,各黄芩素干预组的细胞G1期均受阻滞,阻滞程度与黄芩素干预浓度成正向变化;黄芩素能有效抑制HeLa细胞的迁移,迁移距离与黄芩素干预浓度成反向变化;细胞培养基中MMP2及MMP9的活性受抑制,抑制程度与黄芩素干预浓度成正向变化;MMP2及MMP9 mRNA及蛋白表达随黄芩素干预浓度增加,呈逐渐降低的趋势（P〈0.05,P〈0.01）。结论：黄芩素可有效抑制宫颈癌HeLa细胞的迁移,阻滞细胞周期中G1期、降低MMP2、MMP9活性,下调MMP2和MMP9的表达,发挥抑制宫颈癌HeLa细胞增殖的作用。     

黄芩素对阿霉素致乳鼠心肌细胞损伤的保护作用机制研究

目的：观察黄芩素对阿霉素所致心肌细胞损伤的保护作用及其NF-κB及JNK信号通路的关系。方法：采用乳鼠心肌细胞培养法,实验分为空白对照组、阿霉素处理组、阿霉素合并黄芩素高中低剂量组。MTT法检测心肌细胞存活率,Westernblot法检测NF-κBp65和JNK磷酸化水平。结果：高剂量组黄芩素能够显著对抗阿霉素所致心肌细胞损伤（P〈0．05）,并显著抑制炎症通路NF-κB和细胞凋亡通路JNK的磷酸化水平。结论：黄芩素能抑制NF-κB和JNK的磷酸化水平,以对抗阿霉素所引起的心肌细胞损伤。     

Flavonoid baicalein suppresses adhesion,migration and invasion of MDA-MB-231 human breast cancer cells

Baicalein is a widely used Chinese herbal medicine that has been used historically in anti-inflammatory and anti-cancer therapy. However, the molecular mechanism of its anti-cancer activity remains poorly understood and warrants further investigations. The purpose of this study is to verify the activity of baicalein to inhibit the invasion of MDA-MB-231 human breast cancer cells. The results indicated that baicalein suppressed MDA-MB-231 cell adhesion to fibronectin-coated substrate, wound healing migration and invasion through the Matrigel in a concentration-dependent manner. Western blot and gelatin zymography analysis showed that baicalein significantly inhibited the expression and secretion of matrix metalloproteinases 2/9 (MMP-2/9) in MDA-MB-231 cells. Additionally, treatment of MDA-MB-231 cells with baicalein down-regulated the expression of MMP-2/9 involved mitogen-activated protein kinases (MAPK) signaling pathway. Taken together, baicalein had potential to suppress the adhesion, migration and invasion of MDA-MB-231 cancer cells in vitro and it could serve as a promising drug for the treatment of cancer metastasis.     

Baicalein protects the brain against neuron impairments induced by MPTP in C57BL/6 mice

Many studies of Parkinson's disease suggest that oxidative stress is involved in the neurodegenerative process. Baicalein has been shown to have antioxidant effects. The present study examines the effect of baicalein on 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced neurotoxicity in C57BL/6 mice. MPTP treatment impaired spontaneous motor activity and rotarod performance, but baicalein improved this deficit. Moreover, baicalein at 280 and 560 mg/kg exhibited a protective effect against the MPTP-induced decrease in tyrosine hydroxylase (TH)-positive fibers in the substantia nigra, demonstrated by the immunohistological, morphological and behavioral outcomes. MPTP treatment also decreased dopamine levels in the striatum. However, treatment with baicalein attenuated these decreases in dopamine levels by changing dopamine catabolism and inhibiting dopamine turnover. The neuroprotective effect of baicalein on dopaminergic neurons may partly be due to its antioxidant properties. Therefore, we speculate that baicalein might be a promising candidate for prevention or treatment of oxidative stress-related neurodegenerative disorders such as Parkinson's disease.