... The metabolism of emodin (1,3,8-trihydroxy-6-methylanthraquinone) /was studied/... With rat liver microsomes, the formation of two emodin metabolites, omega-hydroxyemodin and 2-hydroxyemodin, was observed. The rates of formation of omega-hydroxyemodin were not different with microsomes from rats that had been pretreated with inducers for different cytochrome P450 enzymes. Thus, the formation of omega-hydroxyemodin seems to be catalyzed by several cytochrome P450 enzymes at low rates. The formation of 2-hydroxyemodin was increased in liver microsomes from 3-methylcholanthrene-pretreated rats and was inhibited by alpha-naphthoflavone, by an anti-rat cytochrome P450 1A1/2 antibody, and, to a lesser degree, by an anti-rat cytochrome P450 1A1 antibody. These data suggest the involvement of cytochrome P450 1A2 in the formation of this metabolite. However, other cytochrome P450 enzymes also seem to catalyze this reaction. The anthraquinone chrysophanol (1,8-dihydroxy-3-methylanthraquinone) is transformed, in a cytochrome P450-dependent oxidation, to aloe-emodin (1, 8-dihydroxy-3-hydroxymethylanthraquinone) as the major product formed.
The hepatic microsomes derived from various animal species transformed emodin (1,3,8-trihydroxy-6-methylanthraquinone), into an unidentified anthraquinone, along with 2-hydroxy-, 4-hydroxy- and 7-hydroxyemodins. ... This major metabolite /was identified/ as omega-hydroxy-emodin (1,3,8-trihydroxy-6-hydroxymethylanthraquinone). Among 7 animal species, the highest activity to produce this omega-hydroxyemodin was observed in the hepatic microsomes of guinea pig and rat, followed by mouse and rabbit. The microsomal activity to convert emodin into omega-hydroxyemodin was accelerated by the pretreatment of animals with phenobarbital, and inhibited by SKF 525A. The microsomal hydroxylation reactions of the methyl residue and the anthraquinoid nucleus of emodin were presumed to be catalyzed regiospecifically by multiple forms of cytochrome P-450.
... Emodin was biotransformed by the microsomal enzymes into at least 5 quinonoid metabolites, among which one pigment, identified as 2-hydroxyemodin (1,2,3,8-tetrahydroxy-6-methyl-anthraquinone), was proven to be a direct mutagen to the test strain, and the remaining 4 quinonoid metabolites were negative or far less active than this active principle.
来源:Hazardous Substances Data Bank (HSDB)
代谢
大黄素已知的人类代谢物包括大黄素3-羟基-葡萄糖苷酸。
Emodin has known human metabolites that include Emodin 3-hydroxy-glucuronide.
Emodin is biotransformed by the microsomal cytochrome P450 enzymes into active hydroxyemodins such as omega-hydroxyemodin and 2-hydroxyemodin. Emodin glycoside is carried unabsorbed to the large intestine, where it is metabolized to the active aglycones by intestinal bacterial flora. (A3043, A3046)
Emodin is moderately cytotoxic and can inhibit the growth of many cell types by interfering with the cell cycle, possibly by stimulating the expression of p53 and p21. Alternatively, it may do this by creating DNA strand breaks and/or non-covalently binding to DNA and inhibiting the catalytic activity of topoisomerase II. It may also induce apoptosis by inhibiting the electron transport chain, producing reactive oxygen species. Emodin is a strong inhibitor of tyrosine-protein kinase Lck and other tyrosine kinase receptors, which likely contributes to its growth suppressing activity. It may act as a chemopreventive agent by activating DNA repair machinery.
Emodin can also inhibit metastasis by interfering with the activity of matrix metalloproteinases, either directly or through through inhibition of focal adhesion kinase, mitogen-activated protein kinase, and RAC-alpha serine/threonine-protein kinase activation, and partial inhibition of transcription factor AP-1 and nuclear factor NF-kappa-B (NF-kB) transcriptional activities.
Emodin exerts its purgative effects by acting directly or indirectly on colon epithelial cells. This activates the underlying smooth muscle cells, leading to muscle contractility. Possible mechanisms for this effect includes enhancing the hormone motilin, activating muscarinic receptors by triggering the release of acetylcholine, stimulating the protein kinase C-alpha pathway for increased calcium sensibility, inhibiting the secretion of the hormone somatostatin, increasing fluid electrolyte accumulation in the distal ileum and colon, and inhibiting the activity of Na+/K+-ATPase and/or potassium channels.
Emodin's antiinflammatory action is due to its specific inhibition of the transcription factor NF-kB. It also regulates angiogenesis by inhibiting the enzymes casein kinase II and nitric oxide synthase and has shown potent estrogen receptor binding affinity. Emodin can induce the microsomal enzyme cytochrome P-450 1A1, perpetuating its own metabolic activation. (A3043, A3044, A3045, A3046, A3047, A3048, A3049, A3050, A3051, A3052, A3053, A3054)
来源:Toxin and Toxin Target Database (T3DB)
毒理性
致癌物分类
对人类无致癌性（未列入国际癌症研究机构IARC清单）。
No indication of carcinogenicity to humans (not listed by IARC).
来源:Toxin and Toxin Target Database (T3DB)
毒理性
健康影响
长期使用可导致电解质平衡紊乱，尤其是钾缺乏和液体失衡。大黄素还可能对肾细胞造成损伤。
Chronic use can cause disturbances in electrolyte balance, especially potassium deficiency, and fluid imbalance. Emodin may also cause damage to kidney cells. (A3043, A3044)
来源:Toxin and Toxin Target Database (T3DB)
毒理性
暴露途径
口服、皮肤、吸入和parenteral（被污染的药物）。
Oral, dermal, inhalation, and parenteral (contaminated drugs). (A3101)
来源:Toxin and Toxin Target Database (T3DB)
毒理性
症状
大黄具有泻药性质，会导致腹泻。
Emodin has purgative properties and causes diarrhea. (A3043)
Absorption, excretion, tissue distribution and metabolism of the anthraquinone [14C]emodin was studied after a single oral administration (approx. 50 mg/kg) to rats. Urinary excretion amounted to 18(+/- 5)% dose in 24 hr and to 22(+/- 6)% in 72 hr. Metabolites found in pooled urine (0-72 hr) were mostly free anthraquinones (emodin and emodic acid, 16% dose); 3% was conjugated and 3% was non-extractable radioactivity. In 24 hr, 48 +/- 11% and in 120 hr, 68 +/- 8% dose was excreted in the faeces, mostly in the free anthraquinone form. In two cannulated rats biliary excretion reached a maximum at approx. 6 hr and amounted to 49% dose within 15 hr; 70% of biliary activity was in the form of conjugated emodin. The content of radioactivity in most organs decreased significantly between 3 and 5 days. In kidneys, however, the 14C activity was still equiv. to 4.33 ppm. emodin after five days. Mesenterium and fat tissue showed increasing 14C activity from 72 to 120 hr.
Synthesis and antiviral activity of novel thioether derivatives containing 1,3,4-oxadiazole/thiadiazole and emodin moieties
作者：Liangrun Dong、Baojing Song、Jian Wu、Zengxue Wu、Yunying Zhu、Xuewen Chen、Deyu Hu
DOI：10.1080/10426507.2015.1114944
日期：2016.6.2
ABSTRACT ABSTRACT A series of novel thioether derivatives containing 1,3,4-oxadiazole/thiadiazole and emodin moieties were designed and synthesized. The structures of the target compounds were confirmed by 1H NMR, 13C NMR, Infrared, and elemental analysis. The results of bioactivity analysis showed that most of the target compounds exhibited moderate to good antiviralactivity against tobacco mosaic virus
[EN] INHIBITORS OF CREATINE TRANSPORT AND USES THEREOF<br/>[FR] INHIBITEURS DE TRANSPORT DE CRÉATINE ET LEURS UTILISATIONS
申请人：RGENIX INC
公开号：WO2016176636A1
公开（公告）日：2016-11-03
This invention relates to compounds that inhibit creatine transport and/or creatine kinase, pharmaceutical compositions including such compounds, and methods of utilizing such compounds and compositions for the treatment of cancer.
[EN] ISOTHIAZOLOQUINOLONES AND RELATED COMPOUNDS AS ANTI-INFECTIVE AGENTS<br/>[FR] ANTI-INFECTIEUX A BASE D'ISOTHIAZOLOQUINOLONES ET DE SELS CORRESPONDANTS
申请人：ACHILLION PHARMACEUTICALS INC
公开号：WO2005019228A1
公开（公告）日：2005-03-03
The invention provides compounds and salts of Formula (I) and Formula (II): which possess antimicrobial activity. The invention also provides novel synthetic intermediates useful in making compounds of Formula (I) and Formula (II). The variables A1, R2, R3, R5, R6, R7, A8 and R9 are defined herein. Certain compounds of Formula (I) and Formula (II) disclosed herein are potent and selective inhibitors of bacterial DNA synthesis and bacterial replication. The invention also provides antimicrobial compositions, including pharmaceutical compositions, containing one or more compounds of Formula (I) or Formula (II) and one or more carriers, excipients, or diluents. Such compositions may contain a compound of Formula (I) or Formula (II) as the only active agent or may contain a combination of a compound of Formula (I) or Formula (II) and one or more other active agents. The invention also provides methods for treating microbial infections in animals.
Enzymatic Synthesis of Bioactive <i>O</i>-Glucuronides Using Plant Glucuronosyltransferases
作者：Tian Yue、Ridao Chen、Dawei Chen、Jimei Liu、Kebo Xie、Jungui Dai
DOI：10.1021/acs.jafc.9b01769
日期：2019.6.5
glucuronidation of bioactive natural products or drugs to generate glucuronides with better activity and druggability is important in drug discovery and research. In this study, by using two uridine diphosphate (UDP)-dependent glucuronosyltransferases (GATs, UGT88D4 and UGT88D7) from plants, we developed two glucuronidation approaches, pure enzyme catalysis in vitro and recombinant whole-cell catalysis in
在自然界和药物代谢中已发现许多表现出多种药理活性的O-葡萄糖醛酸。生物活性天然产物或药物的葡糖醛酸苷化以产生具有更好活性和可药用性的葡糖醛酸苷在药物发现和研究中很重要。在这项研究中，通过使用来自植物的两种尿苷二磷酸（UDP）依赖性葡萄糖醛酸糖基转移酶（GAT，UGT88D4和UGT88D7），我们开发了两种葡萄糖醛酸化方法，即体外纯酶催化和体内重组全细胞催化，以有效合成生物活性O。 -glucuronides通过天然产物的葡萄糖醛酸化作用。总共14 O获得了具有不同结构的β-葡糖醛酸，包括类黄酮，蒽醌，香豆素和木脂素，其中7种是新化合物。此外，生物合成的O-葡萄糖醛酸中的一种，kaempferol-7- O - β - d-葡萄糖醛酸（3a）可以有效抑制蛋白酪氨酸磷酸酶（PTP）1B，IC 50值为8.02×10 –6M。生物合成的O-葡萄糖醛酸苷也表现出显着的抗氧化活性。
