四君子汤非多糖功效组分的体外人源肠、肝微粒体代谢研究

目的 对四君子汤非多糖组分的主要活性成分进行人源肠、肝微粒体中的代谢过程研究,明确其在肠、肝中的代谢轮廓及代谢差异,为其临床应用提供科学证据。方法 应用Acquity UPLC I-class/VION IMS QTOF技术分析四君子汤非多糖组分中主要活性成分（异甘草苷、甘草素、甘草酸、甘草次酸、人参皂苷Rb₁、人参皂苷CK、白术内酯III）在人源肠、肝微粒体孵育体系下的代谢产物以及代谢转化途径。结果 甘草酸、甘草次酸在人源肠、肝微粒体中均以I相代谢为主;而甘草素、异甘草苷、人参皂苷Rb₁、人参皂苷CK则以肠II相代谢为主。白术内酯III在肠、肝微粒体中代谢均不显著,而四君子汤非多糖功效组分中其他化合物在肠微粒体中代谢速度均比在肝微粒体中更快。此外,甘草皂苷、人参皂苷主要进行脱糖基反应;异甘草苷以脱糖、羟基化等反应为主;甘草素则以葡萄糖醛酸结合为主;白术内酯III则主要发生水解、羟基化反应。结论 阐明了四君子汤非多糖组分中主要活性成分在人体肠道及肝脏中的代谢轮廓及代谢差异,为后续进行四君子汤非多糖功效组分的药效研究提供了数据支持,也为中药复方的功效组分研究提供了思路和策略。     

朝鲜淫羊藿的化学成分（Ⅲ）

 从朝鲜淫羊藿（Epimedium koreanum Nakai）的地上部分分离得到4个化合物，经理化和光谱分析鉴定为大黄素(I)甘草素（Ⅱ)、苜蓿素(Ⅲ)和淫羊藿素(Ⅳ)。均为首次从该植物中获得。     

Liquiritigenin inhibits Aβ25-35-induced neurotoxicity and secretion of Aβ1-40 in rat hippocampal neurons

Aim： To examine whether liquiritigenin, a newly found agonist of selective estrogen receptor-β, has neuroprotective activity against β-amyloid peptide （Aβ） in rat hippocampal neurons.
Methods： Primary cultures of rat hippocampal neurons were pretreated with liquiritigenin （0.02, 0.2, and 2 pmol/L） prior to Aβ25-35 exposure. Following treatment, viability of the cells was measured by 3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide analysis and by a lactate dehydrogenase activity-based cytotoxicity assay. Intracellular Ca^2＋ concentration （[Ca^2＋]i） and levels of reactive oxygen species （ROS）, as well as apoptotic rates, were determined. Our studies were extended in tests of whether liquiritigenin treatment could inhibit the secretion of Aβ1-40 as measured using an ELISA method. In order to analyze which genes may be involved, we used a microarray assay to compare gene expression patterns. Finally, the levels of specific proteins related to neurotrophy and neurodenegeration were detected by Western blotting.
Results： Pretreated neurons with liquiritigenin in the presence of Aβ25-35 increased cell viability in a concentration-dependent manner. Liquiritigenin treatment also attenuated Aβ25-35-induced increases in [Ca^2＋]i and ROS level and decreased the apoptotic rate of neurons. Some genes, including B-cell lymphoma/leukemia-2 （Bcl-2）, neurotrophin 3 （Ntf-3） and amyloid [3 （A4） precursor protein-binding, family B, member 1 （Apbb-1） were regulated by liquiritigenin; similar results were shown at the protein level by Western blotting.
Conclusion： Our results demonstrate that liquiritigenin exhibits neuroprotective effects against Aβ25-35-induced neurotoxicity and that it can decrease the secretion of Aβ1-40. Therefore, liquiritigenin may be useful for further study as a prodrug for treatment of Alzheimer＇s disease.     

HPLC同时测定甘蒲祛斑凝胶中甘草素、异甘草素、甘草查尔酮A的含量

目的: 建立同时测定甘蒲祛斑凝胶中甘草素、异甘草素、甘草查尔酮A含量的方法。方法: 采用高效液相色谱法,Agilent HC-C₁₈色谱柱 (4.6 mm×250 mm,5 μm),流动相0.05%磷酸水(A)-乙腈(B)梯度洗脱(0~4 min,80%A;4~18 min,80%~65% A;18~22 min,65%~62% A;22~25 min,62% A,25~30 min,62%~55% A;30~35 min,55% A,35～45 min,55%~50% A;45~50 min,50%~55% A;50~60 min,55%~80% A),柱温30 ℃,流速0.8 mL·min^-1,检测波长276,368 nm。结果: 甘草素、异甘草素、甘草查尔酮A的线性范围分别为0.050 4~0.403 2 (r=1),0.039 4~0.315 2 (r=1),1.638~8.192 μg (r=0.999 9);甘草素平均回收率为98.81%,RSD 1.7%;异甘草素平均回收率为99.16%,RSD 1.2%;甘草查尔酮A平均回收率为97.68%,RSD 1.0%。结论: 该方法简便、灵敏度高、专属性强,可用于甘蒲祛斑凝胶中3种指标性成分的含量测定。     

Dual Effects of Liquiritigenin on the Proliferation of Bone Cells: Promotion of Osteoblast Differentiation and Inhibition of Osteoclast Differentiation

Bone is constantly controlled by a balance between osteoblastic bone formation and osteoclastic bone resorption. Liquiritigenin is a plant‐derived flavonoid and has various pharmacological effects, such as antioxidative, antitumor, and antiinflammatory effects. Here, we show that liquiritigenin has dual effects on the proliferation of bone cells, regarding the promotion of osteoblast differentiation and the inhibition of osteoclast differentiation. Liquiritigenin‐treated murine osteoblastic MC3T3‐E1 cells showed an increased alkaline phosphatase activity and enhanced phosphorylation of Smad1/5 compared with untreated cells. Moreover, liquiritigenin inhibited osteoclast differentiation, its bone‐resorption activity through slightly decreased the phosphorylation of extracellular signal‐regulated kinase, c‐Jun N‐terminal kinase, and inhibitor of nuclear factor kappa Bα; however, the phosphorylation of Akt and p38 slightly increased in bone marrow‐derived osteoclasts. The expression levels of the osteoclast marker proteins nuclear factor of activated T‐cell cytoplasmic‐1, Src, and cathepsin K diminished. These results suggest that liquiritigenin may be useful as a therapeutic and/or preventive agent for osteoporosis or inflammatory bone diseases. Copyright © 2015 John Wiley & Sons, Ltd.     

AMPK-mediated GSK3β inhibition by isoliquiritigenin contributes to protecting mitochondria against iron-catalyzed oxidative stress

Isoliquiritigenin (ILQ), a flavonoid compound originated from Glycyrrhiza species, is known to activate SIRT1. Arachidonic acid (AA) in combination with iron (a catalyst of auto-oxidation) leads cells to produce excess reactive species with a change in mitochondrial permeability transition. In view of the importance of oxidative stress in cell death and inflammation, this study investigated the potential of ILQ to protect cells against the mitochondrial impairment induced by AA + iron and the underlying basis for this cytoprotection. Treatment with ILQ inhibited apoptosis induced by AA + iron, as evidenced by alterations in the levels of the proteins associated with cell viability: ILQ prevented a decrease in Bcl-x_L, and cleavage of poly(ADP-ribose)polymerase and procaspase-3. Moreover, ILQ inhibited the ability of AA + iron to elicit mitochondrial dysfunction. In addition, superoxide generation in mitochondria was attenuated by ILQ treatment. Consistently, ILQ prevented cellular H₂O₂ production increased by AA + iron, thereby enabling cells to restore GSH content. ILQ treatment enhanced inhibitory phosphorylation of glycogen synthase kinase-3β (GSK3β), and prevented a decrease in the GSK3β phosphorylation elicited by AA + iron, which contributed to protecting cells and mitochondria. GSK3β phosphorylation by ILQ was preceded by AMP-activated protein kinase (AMPK) activation, which was also responsible for mitochondrial protection, as shown by reversal of its effect in the experiments using a dominant negative mutant of AMPK and compound C. Moreover, the AMPK activation led to GSK3β phosphorylation. These results demonstrate that ILQ has the ability to protect cells from AA + iron-induced H₂O₂ production and mitochondrial dysfunction, which is mediated with GSK3β phosphorylation downstream of AMPK.     

Pharmacokinetics of liquiritigenin and its two glucuronides,M1 and M2, in rats with acute hepatitis induced by d-galactosamine/lipopolysaccharide or CCl4

1. Cytoprotective effects of liquiritigenin (LQ) against liver injuries have been reported, but its pharmacokinetics has not been studied in acute hepatitis. Thus, pharmacokinetics of LQ and its two conjugated glucuronide metabolites: 4′-O-glucuronide (M1) and 7-O-glucuronide (M2), in rats with acute hepatitis induced by d-galactosamine/lipopolysaccharide (GalN/LPS) rats or carbon tetrachloride-treated (CCl₄-treated) rats were evaluated.

2. LQ was administered intravenously (20?mg kg^?1) and orally (50?mg kg^?1) to control GalN/LPS and CCl₄-treated rats. Expression of uridine 5′-diphospho-glucuronosyltransferases 1A (UGT1A) and in vitro metabolism of LQ in hepatic and intestinal microsomes were also measured.

3. After intravenous administration of LQ, area under the plasma concentration-time curve (AUC) of LQ in GalN/LPS rats was significantly smaller than that in controls due to faster non-renal clearance, as a result of its greater free fraction in plasma and faster hepatic blood flow rate than the controls. In CCl₄-treated rats, the AUC_{M1, 0?8 h}/AUC_LQ and AUC_{M2, 0?8 h}/AUC_LQ ratios were significantly greater than the controls due to decrease in biliary excretion of M1 and M2. However, no significant pharmacokinetic changes were observed in both acute hepatitis rats after oral administration due to comparable intestinal metabolism of LQ.

4. Modification of oral dosage regimen of LQ may not be necessary in patients with acute hepatitis; but human studies are required.

     

光叶决明中1个新的二聚苯丙素类化合物

目的对决明属植物光叶决明Cassia floribunda茎叶的化学成分进行研究。方法运用硅胶、MCI、RP-18、TLC、HPLC等多种色谱技术进行分离纯化,根据理化性质和波谱数据鉴定化合物的结构。结果从光叶决明90%乙醇提取物中分离得到18个化合物,分别鉴定为决明顺反二聚苯丙素(1)、反式对羟基肉桂酸乙酯(2)、shonanin(3)、邻苯二甲酸二丁酯(4)、1,6,8-三羟基-3-甲基蒽醌(5)、2,5-二甲基-7-羟基-色原酮(6)、2-(2′-羟丙基)-5-甲基-7-羟基色酮(7)、4′,7-二羟基-5-甲氧基黄酮(8)、柯伊利素(9)、山柰酚(10)、芹菜素(11)、3-甲氧基槲皮素(12)、6-demethoxycapillarisin(13)、7,4′-二羟基黄酮(14)、木犀草素(15)、butin(16)、甘草素(17)和圣草酚(18)。结论化合物1为新的苯丙素类化合物;化合物2～18均为首次从该植物中分离得到,其中,化合物2～4、8、9、11、13、14、16～18为首次从决明属植物中分离得到。     

甘草素在体外不同种属肝微粒体中的代谢差异研究

目的对甘草苷的苷元甘草素在体外不同种属肝微粒体中的代谢差异进行比较研究,为甘草苷的进一步研究开发提供参考依据。方法甘草素与不同种属,包括大鼠、小鼠、人、犬及猴的肝微粒体进行孵育,比较其代谢稳定性和代谢转化情况。代谢稳定性通过底物消除法分析甘草素的剩余底物浓度水平随时间的变化,计算体外消除半衰期(t1/2)。进一步对甘草素在肝微粒体孵育后生成的代谢产物谱以及代谢途径进行分析。结果在I相肝微粒体孵育体系中,甘草素在5个种属肝微粒体中发生代谢的t1/2依次为大鼠小鼠人猴犬;在II相肝微粒体孵育体系中,甘草素代谢都非常快,除小鼠外,均在5 min内下降50%以上。甘草素与人肝微粒体进行II相孵育产生的代谢产物谱和猴的相同,其余种属则与人有明显不同。结论甘草素在猴肝微粒体中的代谢稳定性和代谢产物谱均与人最相似,其次为犬肝微粒体,大鼠和小鼠则与人存在明显差异。在进一步的临床前药代和毒理研究中可选用猴或犬作为模型动物。     

Liquiritigenin regulates insulin sensitivity and ameliorates inflammatory responses in the nonalcoholic fatty liver by activation PI3K/AKT pathway

Nonalcoholic fatty liver disease (NAFLD) is a prevalent long-term disease in the world. Liquiritigenin (LQ) is protective against a variety of hepatotoxins. Herein, we report the potential mechanism of LQ on a high-fat diet (HFD) induced NAFLD. NAFLD mice model was established by HFD for 12 weeks, and LQ treatment for 1 week. Commercially available assay kits measure liver triglycerides (TG) and total cholesterol (TC) levels. Plasm TC, TG, high-density-lipoprotein (HDL-C), and low-density-lipoprotein cholesterol (LDL-C) levels were also monitored by biochemistry. Enzyme linked immunosorbent assay (ELISA) kits were performed to analyze the pro-inflammatory factors, and intraperitoneal glucose tolerance test (IPGTT), insulin tolerance test (IPITT), and serum insulin were also determined. GO and KEGG pathway enrichment analysis was employed to analyze the overlapping genes of LQ targets and NAFLD development-related targets. Western blot was performed on key proteins of the enriched signaling pathway. HFD mice showed significant increases in hepatic TG and TC, and plasm TC, TG, and LDL-C in blood lipids, while HDL-C significantly decreased, and LQ treatment reversed their levels (p < 0.05). LQ also alleviated HFD-induced elevated levels of IPGTT, IPITT, and homeostasis model assessment of insulin resistance (HOMA-IR). And serum levels of the pro-inflammatory factor were also suppressed by LQ. PI3K/AKT pathway was enriched by KEGG pathway enrichment, and its key proteins p-PI3K and p-AKT were elevated after LQ treatment (p < 0.05). We found for the first time that LQ improves lipid accumulation, alleviates insulin resistance, and suppresses inflammatory responses in NAFLD mice, which might be associated with the activation of the PI3K/AKT pathway.