Synthesis and phototoxicity of isomeric 7,9-diglutathione pyrrole adducts: Formation of reactive oxygen species and induction of lipid peroxidation

Pyrrolizidine alkaloids (PAs) are hepatotoxic, genotoxic, and carcinogenic in experimental animals. Because of their widespread distribution in the world, PA-containing plants are probably the most common poisonous plants affecting livestock, wildlife, and humans. Upon metabolism, PAs generate reactive dehydro-PAs and other pyrrolic metabolites that lead to toxicity. Dehydro-PAs are known to react with glutathione (GSH) to form 7-GSH-(+/−)-6,7-dihydro-7-hydroxy-1-hydroxymethyl-5H-pyrrolizine (7-GS-DHP) in vivo and in vitro and 7,9-diGS-DHP in vitro. To date, the phototoxicity of GS-DHP adducts has not been well studied. In this study, we synthesized 7-GS-DHP, a tentatively assigned 9-GS-DHP, and two enantiomeric 7,9-diGS-DHP adducts by reaction of dehydromonocrotaline with GSH. The two 7,9-diGS-DHPs were separated by high performance liquid chromatography (HPLC) and their structures were characterized by ¹H nuclear magnetic resonance (NMR) and ¹H–¹H correlation spectroscopy (COSY) NMR spectral analysis. Photoirradiation of 7-GS-DHP, 9-GS-DHP, and the two 7,9-diGS-DHPs as well as dehydromonocrotaline, dehydroheliotrine, and the 7-R enantiomer of DHP (DHR), by UVA light at 0 J/cm², 14 J/cm², and 35 J/cm² in the presence of a lipid, methyl linoleate, all resulted in lipid peroxidation in a light dose-responsive manner. The levels of lipid peroxidation induced by the two isomeric 7,9-diGS-DHPs were significantly higher than that by 7-GS-DHP and 9-GS-DHP. When 7,9-diGS-DHP was irradiated in the presence of sodium azide (NaN₃), the level of lipid peroxidation decreased; lipid peroxidation was enhanced when methanol was replaced by deuterated methanol. These results suggest that singlet oxygen is a product induced by the irradiation of 7,9-diGS-DHP. When irradiated in the presence of superoxide dismutase (SOD), the level of lipid peroxidation decreased, indicating that lipid peroxidation is also mediated by superoxide. These results indicate that lipid peroxidation is mediated by reactive oxygen species (ROS). These results suggest that 7,9-diGS-DHPs are phototoxic, generating lipid peroxidation mediated by ROS.     

Definitive diagnosis of hepatic sinusoidal obstruction syndrome induced by pyrrolizidine alkaloids

OBJECTIVE: Hepatic sinusoidal obstruction syndrome (HSOS) induced by a Chinese medicinal herb Tusanqi is increasingly being reported in recent years. The aim of the study was to investigate the possibility of using blood pyrrole‐protein adducts test as a confirmatory diagnostic method. METHODS: Patients with HSOS according to international diagnostic criteria associated with Tusanqi from January 2006 to August 2010 in Zhongshan Hospital Fudan University were included and clinical features were collected. Pyrrole‐protein adducts in blood sample were determined with ultra performance liquid chromatography‐mass spectrometry (UPLC‐MS) while pyrrolizidine alkaloids (PAs) in available herbal preparations were analyzed by high performance liquid chromatography‐ultraviolet (HPLC‐UV). RESULTS: Five patients (age 41–72 years, median age 54 years, all women) were included. Ascites (5/5), jaundice (5/5) and hepatomegaly (4/5) were common manifestations. The imaging features were diffused, patchy hepatic enhancement, periportal edema and ascites. Pathology ascertained that blood flow was obstructive at the site of sinusoid. PAs (Seneionine and seneciphylline) were identified in all the three available herbal preparations ingested by the HSOS patients. Pyrrole‐protein adducts were unequivocally found in all the five blood samples. Two patients recovered, two developed chronic illness and one died due to liver failure and hepatic encephalopathy. CONCLUSIONS: The detection of blood pyrrole‐protein adducts using a UPLC‐MS approach is a specific, reliable, unambiguous and confirmatory test for HSOS induced by PA, and should be used together with the conventional HSOS clinical diagnostic criteria for the definitive diagnosis of PA‐induced HSOS.     

无叶假木贼的化学成分及抗菌活性研究

目的 研究无叶假木贼Anabsis aphylla的化学成分及其抗菌活性。方法 采用RP-C₁₈、Sephadex LH-20、硅胶等柱色谱进行分离纯化,根据理化性质和波谱数据鉴定化合物结构。采用MTT比色法对化合物进行抗枯草芽孢杆菌Bacillus subtilis、番茄疮痂病菌Xanthomonas vesicatoria、溶血葡萄球菌Staphylococcus haemolyticus、根癌土壤杆菌Agrobacterium tumefaciens、黄瓜角斑病菌Pseudomonas syringae pv.lachrymans活性筛选。结果 从无叶假木贼中分离了10个化合物,分别鉴定为假木贼碱(1)、N-甲基假木贼碱(2)、6-(diethylamino)-[2,3′-bipyridin]-3-ol(3)、2-(2-(pyridine-3-yl) pyridin-5-yl)-6-(pyridin-3-yl)piperidine(4)、2-(pyridine-3-yl)-5-(6-(pyridine-3-yl) pyridine-2-yl) pyridin...     

生物碱类化合物抗病毒活性及其机制研究进展

生物碱是普遍存在于植物体内的含氮次生代谢产物,具有广泛的生物活性。研究表明,生物碱类化合物对多种病毒表现出良好的抑制作用和广谱的抗病毒活性,成为近年来抗病毒小分子化合物研究的新焦点。研究证实,生物碱对甲型流感病毒、乙型肝炎病毒、丙型肝炎病毒、单纯疱疹病毒、艾滋病毒、寨卡病毒、柯萨奇病毒和烟草花叶病毒等表现出显著的抑制作用,其抗病毒机制主要包括抑制病毒吸附和进入、减少病毒RNA和蛋白质合成、促进细胞凋亡和自噬、调节各种病毒相关蛋白以及通路等。根据生物碱的抗病毒种类进行分类,以氧化苦参碱、麻黄碱、石斛碱等为例,综述了常见生物碱抗病毒作用特点和机制,为生物碱类抗病毒小分子化合物的研究提供参考。     

Neuropharmacological effects of Aconiti Lateralis Radix Praeparata

Aconiti Lateralis Radix Praeparata (Fuzi in Chinese), which are the lateral roots of Aconitum Carmichaelii Debx, is widely used in China to treat many neurological diseases. Fuzi, in its various forms, has many neuropharmacological effects. It can act as an analgesic and help with depression, epilepsy, and dementia. However, the neuropharmacological effects of Aconiti Lateralis Radix Praeparata are seldom comprehensively reviewed. In this review, the neuropharmacological activities of some components contained in Aconiti Lateralis Radix Praeparata are considered. These include aconitine, mesaconitine, hypaconitine, total alkaloid, polysaccharide-1, benzoylmesaconine, fuziline, songorine, and napelline. We also specifically discuss the antidepressant effects of total alkaloids and polysaccharide-1. This review may provide a theoretical basis for further utilization of Aconiti Lateralis Radix Praeparata for diseases that affect the central nervous system.     

麦芽总生物碱颗粒剂的制备

目的:在前期药效实验的基础上,提取麦芽总生物碱,优选麦芽总生物碱颗粒剂成型制备工艺,得到稳定均一,质量合格的颗粒制剂。方法:利用超声提取法,提取麦芽总生物碱;采用酸性染料比色法测定麦芽中总生物碱的含量;拟选6个处方完成颗粒剂的制备,并以休止角、成型率、堆密度和吸湿性等为指标,应用综合评分法对各处方进行打分,筛选出最优的辅料处方,完成辅料用量比例的优化,并筛选出最佳润湿剂;对制备所得到的麦芽总生物碱颗粒的溶化性,粒度及干燥失重等进行测定。结果:以糊精和乳糖比例为1:1的混合物作为辅料,并按1:1的比例混合麦芽总生物碱浸膏粉与辅料,选取80%的乙醇作为润湿剂,制备所得颗粒剂大小均一,成型率最高。结论:本文成功优选出了麦芽总生物碱颗粒剂的制备工艺,制成的颗粒溶化性好,成型率佳,制备方法稳定可靠。     

Relationship between blood harmane and harmine concentrations in familial essential tremor, sporadic essential tremor and controls

IntroductionHarmane, a potent tremor-producing β-carboline alkaloid, may play a role in the etiology of essential tremor (ET). Blood harmane concentrations are elevated in ET cases compared with controls yet the basis for this elevation remains unknown. Decreased metabolic conversion (harmane to harmine) is one possible explanation. Using a sample of >500 individuals, we hypothesized that defective metabolic conversion of harmane to harmine might underlie the observed elevated harmane concentration in ET, and therefore expected to find a higher harmane to harmine ratio in familial ET than in sporadic ET or controls.MethodsBlood harmane and harmine concentrations were quantified by high performance liquid chromatography.ResultsThere were 78 familial ET cases, 187 sporadic ET cases, and 276 controls. Blood harmane and harmine concentrations were correlated with one another (Spearman's r = 0.24, p < 0.001). The mean (±SD) harmane/harmine ratio = 23.4 ± 90.9 (range = 0.1–987.5). The harmane/harmine ratio was highest in familial ET (46.7 ± 140.4), intermediate in sporadic ET (28.3 ± 108.1), and lowest in controls (13.5 ± 50.3) (p = 0.03). In familial ET cases, there was no association between this ratio and tremor severity (Spearman's r = 0.08, p = 0.48) or tremor duration (Spearman's r = 0.14, p = 0.24).ConclusionThe basis for the elevated blood harmane concentration, particularly in familial ET, is not known, although the current findings (highest harmane/harmine ratio in familial ET cases) lends support to the possibility that it could be the result of a genetically-driven reduction in harmane metabolism.     

寒痹贴的提取工艺优选

目的:优选寒痹贴的最佳提取工艺。方法:草乌以总生物碱的提取量为考察指标,采用正交试验优选醇提工艺;赤芍等6味中药以芍药苷的提取量为考察指标,采用正交试验优选水煎工艺。结果:寒痹贴的最佳提取工艺为草乌加70%乙醇6倍,回流2次,每次2 h;赤芍等药材加水8倍量,煎煮3次,每次1 h。结论:优选出的提取工艺合理、可行,为其生产提供了科学依据。     

生麦芽生物碱对高泌乳素血症模型大鼠激素水平的影响

目的 研究生麦芽生物碱对高泌乳素血症（HPRL）模型大鼠泌乳素（PRL）、雌二醇（E2）、孕酮（P）等激素的影响,初步明确生麦芽回乳作用的有效部位。方法 选用雌性未孕Wistar大鼠,背部皮下注射盐酸甲氧氯普胺注射液制备HPRL模型。造模成功后,各组均胃饲给予相应的药物治疗,连续20 d。末次给药后取血,应用ELISA法检测血清中PRL、E2、P、促卵泡激素（FSH）、促黄体生成素（LH）的含量,观察生麦芽不同提取部位对HPRL大鼠各激素水平的影响。结果 与模型组比较,生麦芽生物碱高、低剂量组大鼠血清PRL水平明显下降（P＜0.01）,高剂量组还可升高E2、P水平（P＜0.05或P＜0.01）。结论 生麦芽生物碱对HPRL模型大鼠有保护作用,其作用机制可能与其对PRL、E2、P激素水平的调节作用有关。     

吴茱萸化学成分研究

目的 研究吴茱萸Euodia rutaecarpa干燥果实的化学成分。方法 采用硅胶、Sephadex LH-20等开放柱色谱及半制备HPLC等方法对吴茱萸乙醇提取物进行分离纯化,并根据理化性质和波谱数据鉴定化合物的结构。结果 从吴茱萸95%乙醇提取物中分离得到11个化合物,分别鉴定为吴茱萸碱（evodiamine,1）、吴茱萸次碱（rutaecarpine,2）、3-(2′-羟基乙酰基)-吲哚（3-hydroxyacetylindole,3）、N-反式对羟基肉桂酰基-对羟基苯乙胺 [N-(trans-p-coumaroyl)-tyramine,4]、N-顺式对羟基肉桂酰基-对羟基苯乙胺 [N-(cis-p-coumaroyl)-tyramine,5]、白鲜碱（dictamnine,6）、吴茱萸春（evolitrine,7）、6-甲氧基白鲜碱（6-methoxydictamnine,8）、茵芋碱（skimmiamine,9）、7-羟基吴茱萸次碱（7-hydroxyrutaecarpine,10）、阿塔宁I（atanine I,11）。结论 化合物3为首次从该属植物中分离得到;化合物4～11为首次从该植物中分离得到。