The ethanol extract of Rhizoctonia rhizome was discovered to have substantial nematicidal action against two nematodes, namely the southern root-knot nematode and the pine wood nematode, during the screening process of novel agrochemicals derived from traditional Chinese medicinal ingredients. Columbianetin, Falcarindiol, Falcarinol, and Isoimperatorin were the four components of the ethanol extract that were separated based on bioactivity-guided fractionation. Isomperatorin's LC50 value against the pine wood nematode is 21.83 μg/mL. While columbianetin was just twice as harmful as the dark treatment, falcarindiol, falcarinol, and isoimperatorin were nearly five times more poisonous to Meloidogyne incognita after being exposed to a 15-minute UV light therapy. It has been demonstrated that isoimperatorin exhibits insecticidal activity against a range of insects, including cabbage aphids (Brevicoryne bassicae) [2]. The active component of the extract from Angelica dahurica dahurica (AD) included isoimperatorin [3]. An internal standard (IS) that is frequently utilized is isoimperatorin [4].

Metabolism / Metabolites
Highly active and recoverable nanobioreactors prepared by immobilizing rat liver microsomes on magnetic nanoparticles (LMMNPs) were utilized in metabolic study of Angelica dahurica extracts. Five metabolites were detected in the incubation solution of the extracts and LMMNPs, which were identified by means of HPLC-MS as trans-imperatorin hydroxylate (M1), cis-imperatorin hydroxylate (M2), imperatorin epoxide (M3), trans-isoimperatorin hydroxylate (M1') and cis-isoimperatorin hydroxylate (speculated M2'). Compared with the metabolisms of imperatorin and isoimperatorin, it was found that the five metabolites were all transformed from these two major compounds present in the plant. Since no study on isoimperatorin metabolism by liver microsomal enzyme system has been reported so far, its metabolites (M1' and M3') were isolated by preparative HPLC for structure elucidation by (1) H-NMR and MS(2) analysis. M3' was identified as isoimperatorin epoxide, which is a new compound as far as its chemical structure is concerned. However, interestingly, M3' was not detected in the metabolism of the whole plant extract. In addition, a study with known chemical inhibitors on individual isozymes of the microsomal enzyme family revealed that CYP1A2 is involved in metabolisms of both isoimperatorin and imperatorin, and CYP3A4 only in that of isoimperatorin.
Biotransformation studies conducted on the furanocoumarins isoimperatorin (1) and imperatorin (3) have revealed that 1 was metabolized by Glomerella cingulata to give the corresponding reduced acid, 6,7-furano-5-prenyloxy hydrocoumaric acid (2), and 3 was transformed by G. cingulata to give the dealkylated metabolite, xanthotoxol (4) in high yields (83% and 81%), respectively. The structures of the new compound 2 have been established on the basis of spectral data. The metabolites 2 and 4 were tested for the beta-secretase (BACE1) inhibitory activity in vitro, and metabolite 2 slightly inhibited the beta-secretase activity with an IC(50) value of 185.6+/-6.8 uM. The metabolite 4 was less potent activity than compounds 1-3. In addition, methyl ester (2Me), methyl ether (2a) and methyl ester and ether (2aMe) of 2 were synthesized, and investigated for the ability to inhibit beta-secretase. Compound 2aMe exhibited the best beta-secretase inhibitory activity at the IC(50) value 16.2+/-1.2 uM and found to be the 2aMe showed competitive mode of inhibition against beta-secretase with K(i) value 11.3+/-2.8 uM.
Paraoxonase (PON1) is a key enzyme in the metabolism of organophosphates. PON1 can inactivate some organophosphates through hydrolysis. PON1 hydrolyzes the active metabolites in several organophosphates insecticides as well as, nerve agents such as soman, sarin, and VX. The presence of PON1 polymorphisms causes there to be different enzyme levels and catalytic efficiency of this esterase, which in turn suggests that different individuals may be more susceptible to the toxic effect of OP exposure.

Toxicity Summary
IDENTIFICATION AND USE: Isoimperatorin is a solid. Isoimperatorin was found in Chinese medicine tablets. It is used as laboratory chemical, manufacture of substances. HUMAN STUDIES: Coumarins from A. dahurica, including isoimperatorin markedly inhibited melatonin metabolism in vivo and in vitro. Isoimperatorin inactivated cytochromes P450 A2 and 2B6. ANIMAL STUDIES: Isoimperatorin was photoirritant when tested in mice. Isoimperatorin given to mice orally at 40 mg/kg altered serum activities of alanine transaminase, aspartate aminotransferase, alkaline phosphatase, and/or levels of albumin, showing hepatotoxicity. Isoimperatorin inhibited proliferation of bovine cerebral microvascular endothelial cell stimulated by platelet-derived growth factor. Isoimperatoin was capable of inhibiting carcinogen activation by cytochrome P450 1B1. ECOTOXICITY STUDIES: Furocoumarins such as imperatorin and isoimperatorin accumulating in the older shoots of Pituranthos triradiatus acted as natural protectants against grazing. Only hyrax (Procavia capensis syriaca) that had eaten old branches and had been left in the sunlight developed photosensitization symptoms.
Isoimperatorin is a cholinesterase or acetylcholinesterase (AChE) inhibitor. A cholinesterase inhibitor (or 'anticholinesterase') suppresses the action of acetylcholinesterase. Because of its essential function, chemicals that interfere with the action of acetylcholinesterase are potent neurotoxins, causing excessive salivation and eye-watering in low doses, followed by muscle spasms and ultimately death. Nerve gases and many substances used in insecticides have been shown to act by binding a serine in the active site of acetylcholine esterase, inhibiting the enzyme completely. Acetylcholine esterase breaks down the neurotransmitter acetylcholine, which is released at nerve and muscle junctions, in order to allow the muscle or organ to relax. The result of acetylcholine esterase inhibition is that acetylcholine builds up and continues to act so that any nerve impulses are continually transmitted and muscle contractions do not stop. Among the most common acetylcholinesterase inhibitors are phosphorus-based compounds, which are designed to bind to the active site of the enzyme. The structural requirements are a phosphorus atom bearing two lipophilic groups, a leaving group (such as a halide or thiocyanate), and a terminal oxygen. The mechanism of action many furocoumarins is based on their ability to form photoadducts with DNA and other cellular components such as RNA, proteins, and several proteins found in the membrane such as phospholipases A2 and C, Ca-dependent and cAMPdependent protein-kinase and epidermal growth factor. Furocoumarins intercalate between base pairs of DNA and after ultraviolet-A irradiation, giving cycloadducts. (L579).

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Interactions
BACKGROUND AND PURPOSE: Herbs which are widely used as food and medicine, are involved in many physiopathological processes. Melatonin is a human hormone, synthesized and secreted by the pineal gland, with a range of biological functions. Here, we have evaluated the potential influences of components extracted from common herbs on melatonin metabolism in humans. EXPERIMENTAL APPROACH: An in vivo pharmacokinetic study involving 12 healthy subjects, in vitro incubations with human liver microsomes (HLMs) and recombinant human cytochrome P (CYP) isoenzymes and an in silico quantitative structure-activity relationship (QSAR) model analysis using comparative molecular field analysis and comparative molecular similarity indices analysis methods were employed to explore these interactions. KEY RESULTS: After systematic screening of 66 common herbs, Angelica dahurica exhibited the most potent inhibition of melatonin metabolism in vitro. The in vivo pharmacokinetic study indicated inhibition of melatonin metabolism, with approximately 12- and 4-fold increases in the AUC and Cmax of melatonin in human subjects. Coumarins from A. dahurica, including imperatorin, isoimperatorin, phellopterin, 5-methoxypsoralen and 8-methoxypsoralen, markedly inhibited melatonin metabolism with Ki values of 14.5 nM, 38.8 nM, 6.34 nM, 5.34 nM and 18 nM respectively, through inhibition of CYP 1A2, 1A1 and 1B1 in HLMs. A QSAR model was established and satisfactorily predicted the potential risk of coumarins for inhibition of melatonin metabolism in vivo. CONCLUSION AND IMPLICATIONS: Coumarins from A. dahurica inhibited melatonin metabolism in vivo and in vitro. Our findings provide vital guidance for the clinical use of melatonin.
This study was designed to investigate the antigenotoxic effects of a series of naturally occurring furanocoumarins (NOFs) including isoimperatorin, imperatorin, (+)-oxypeucedanin, (+)-byakangelicol, and (+)-byakangelicine on antigenotoxic activities against genotoxicity induced by carcinogens [furylfuramide and N-methyl-N'-nitro-N-nitrosoguanidine], and procarcinogens 2-[2-(acetylamino)-4-amino-5-methoxyphenyl]-5-amino-7-bromo-4-chloro-2H-benzotriazole (PBTA-4) and 2-amino-3,4-dimethyl-3H-imidazo-[4,5-f] quinoline (MeIQ)] to genotoxic metabolites catalyzed by rat S9 or rat and human recombinant cytochrome P450 (CYP) 1As by using the umu test based on SOS response. Five different NOFs, which were found in the human diets, strongly inhibited the umuC induction by procarcinogens, but /were not/ affected by carcinogens. Notably, isoimperatorin and (+)-byakangelicol were found to be potent inhibitors on the metabolic activation of PBTA-4 and MeIQ to genotoxic metabolites catalyzed by rat and human CYP1A1, or rat and human CYP1A2, respectively. In addition, to elucidate the mechanism of their antigenotoxic effects against procarcinogens, the effects of NOFs on rat and human CYP1A1- or rat and human CYP1A2-related enzyme activities of 7-ethoxyresorufin-O-deethylase (EROD) were also investigated. Reduction of the EROD activities by some of the NOFs with IC(50) values of 0.23-20.64 uM was found to be due to strong inhibition of CYP1A1 and CYP1A2 dependent monooxygenases. Furthermore, the mechanism of inhibitions by NOFs on human CYP1A1 and CYP1A2 was analyzed by means of Dixon plots plus Cornish-Bowden plots. The kinetic studies of inhibition types revealed that these compounds inhibited the human CYP1A1 and CYP1A2 a variety of modes rather than by a uniform one. Moreover, experiments with a two-stage incubation indicated that NOFs, except for imperatorin, inhibited human CYP1A1 in a mechanism-based manner, but directly inhibited human CYP1A2. This data suggest that certain NOFs, to which humans are exposed in the diet, may be capable of affecting the metabolic activation of procarcinogens due to inhibitions of CYP1A1 and CYP1A2 enzymes.

[1]. Acetylcholinesterase inhibitors from the roots of Angelica dahurica. Arch Pharm Res. 2002 Dec;25(6):856-9.

[2]. Identification of Nematicidal Constituents of Notopterygium incisum Rhizomes against Bursaphelenchus xylophilus and Meloidogyne incognita. Molecules. 2016 Sep 23;21(10). pii: E1276.

[3]. Angelica dahurica Extracts Improve Glucose Tolerance through the Activation of GPR119. PLoS One. 2016 Jul 8;11(7):e0158796.

[4]. The pharmacokinetics, bioavailability and excretion of bergapten after oral and intravenous administration in rats using high performance liquid chromatography with fluorescence detection. Chem Cent J. 2016 Oct 14;10:62.

Isoimperatorin is a member of the class of psoralens that is psoralen substituted by a prenyloxy group at position 5. Isolated from Angelica dahurica and Angelica koreana, it acts as a acetylcholinesterase inhibitor. It has a role as a metabolite and an EC 3.1.1.7 (acetylcholinesterase) inhibitor.
Isoimperatorin has been reported in Salvia miltiorrhiza, Angelica gigas, and other organisms with data available.
Isoimperatorin is a tumor necrosis factor antagonist isolated from Glehniae root or from Poncirus trifoliate Raf (L579). Furocoumarins, are phototoxic and photocarcinogenic. They intercalate DNA and photochemically induce mutations. Furocoumarins are botanical phytoalexins found to varying extents in a variety of vegetables and fruits, notably citrus fruits. The levels of furocoumarins present in our diets, while normally well below that causing evident acute phototoxicity, do cause pharmacologically relevant drug interactions. Some are particularly active against cytochrome P450s. For example, in humans, bergamottin and dihydroxybergamottin are responsible for the 'grapefruit juice effect', in which these furanocoumarins affect the metabolism of certain drugs.
See also: Angelica archangelica root (part of).

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Therapeutic Uses
/EXPL THER/ CONTEXT: Prangos ferulacea (L.) Lindl. (Apiaceae) is a perennial plant found in the Middle-East, where it is commonly used as an antispasmodic and anti-inflammatory agent. It is a rich source of coumarins. OBJECTIVE: To purify several coumarins from P. ferulacea and to screen their cytotoxicity and anti-herpes activity. MATERIALS AND METHODS: Acetone extract of roots of P. ferulacea was subjected to several chromatographic separations to render pure coumarins (1-8). Anti-herpes virus effects of 1-7 were evaluated at concentration 2.5, 5, and 10 ug/mL, on a confluent monolayer of Vero cells infected with 25 PFU /plaque-forming units/ of HSV1. Cytotoxic effects of 1 and 2 were evaluated on an A2780S cell line using the MTT assay. The cells were exposed to a series of concentrations of coumarins (0.01-2.5 mM, 37 °C, 72 hr). RESULTS: Compounds 1-8 were identified as osthole, isoimperatorin, oxypeucedanin, psoralen, oxypeucedanin hydrate, gosferol, oxypeucedanin methnolate, and pranferol. This is the first report of occurrence of 4 and 7 in this plant. Compound 1 showed a viability of 9.41% +/- 2.4 at 2.5 mM on A2780S cells (IC50 = 0.38 mM). The cell survival of 2 at 2.5 mM was 46.86% +/- 5.5 with IC50 equal to 1.1 mM. DISCUSSION AND CONCLUSION: Compound 1 shows cytotoxic effects on the A2780S cell line. Compound 2 is a cyclooxygenase-2 inhibitor and the A2780S cell line does not express COX-2 which may interpret the non-toxic effect of the compound on this cell line. None of the tested compounds showed an anti-HSV effect at non-toxic concentrations.
/EXPL THER/ Radix Angelicae dahuricae, containing coumarins, which might affect cytochrome P450 enzyme (CYP450) activity, has been co-administered with ligustrazine, a substrate of CYP450s, for the clinical treatment of migraine. However, whether a pharmacokinetic-based synergy exists between Radix Angelicae dahuricae and ligustrazine is still unknown. In this study, the total coumarin extract (TCE) of Radix Angelicae dahuricae(50 mg/kg, orally) /for three days/ reinforced the anti-migraine activity of ligustrazine by declining head scratching, plasma calcitonin gene-related peptide, and serum nitric oxide, as well as increasing plasma endothelin levels in rats (p < 0.05). Moreover, the pharmacokinetic study reflected that TCE potentiated the area under the concentration-time curve of ligustrazine and prolonged its mean retention time in rats (p < 0.05). Besides, the IC50 for TCE, imperatorin and isoimperatorin inhibiting ligustrazine metabolism were 5.0 +/- 1.02, 1.35 +/- 0.46, 4.81 +/- 1.14 ug/mL in human liver microsomes, and 13.69 +/- 1.11, 1.19 +/- 1.09, 1.69 +/- 1.17 ug/mL in rat liver microsomes, respectively. Moreover, imperatorin and isoimperatorin were CYP450s inhibitors with IC50 < 10 uM for CYP1A2, 2C9, 2D6, and 3A4. Therefore, this study concluded that Radix Angelicae dahuricae could increase ligustrazine plasma concentration and then reinforce its pharmacological effect by inhibiting its metabolism through interference with CYP450s. This could be one mechanism for the synergy between Radix Angelicae dahuricae and ligustrazine on migraine treatment.
/EXPL THER/ Previous studies have shown that isoimperatorin (IO), a furanocoumarin isolated from several medicinal plants, has antimycobacterial activity against Mycobacterium tuberculosis strain H37Rv (ATCC 27294). This study demonstrated that IO has antimycobacterial activity against 2 drug-sensitive and 6 drug-resistant isolates, with minimum inhibitory concentrations (MICs) of 50-100 ug/mL and 100-200 ug/mL, respectively. IO exhibited synergistic antimycobacterial effects with rifampin (RMP), isoniazid (INH) and ethambutol (EMB) against 6 drug-resistant strains, with fractional inhibitory concentration index (FICI) values of 0.133-0.472, 0.123-0.475 and 0.124-0.25, respectively. The IO/RMP, IO/INH and IO/EMB combination treatments had synergistic effects or no interaction in the 2 drug-sensitive strains and the standard strain ATCC 27294. The synergism of combined drugs against drug-resistant strains was better than drug-sensitive strains. No antagonism was observed in with the aforementioned combinations against all strains tested. IO exhibited relatively low cytotoxicity to Vero cells. Our results indicate that IO may serve as promising a template for future antimycobacterial drug development. SIGNIFICANCE AND IMPACT OF THE STUDY: ... The results indicated that the antimycobacterial activity of IO was modest; however, IO was a useful and effective agent against Myco. tuberculosis when it was combined with first-line antimycobacterial drugs and is worthy of further development as a lead compound for the development of novel antimycobacterial therapeutic agents.
/EXPL THER/ Typically chemopreventive agents either induce phase II detoxifying enzymes or inhibit the cytochrome P450 enzymes (CYPs) that are required for the metabolism of carcinogens. In this study, we isolated a coumarin compound, isoimperatorin from Poncirus trifoliata Raf., and studied its protective effects against aflatoxin B1 (AFB1)-induced cytotoxicity in H4IIE cells. Isoimperatorin (>0.3 uM) significantly inhibited the cytotoxic effect of AFB1. CDNB [1-chloro-2,4-dinitrobenzene; glutathine S-transferase (GST) subtype-non-specific] and NBD (7-chloro-4-nitrobenzo-2-oxa-1,3-diazole; GSTalpha type-specific) assays revealed that isoimperatorin (0.3-3 uM) increased GST activity in a concentration-dependent manner. Western blot analyses using subtype-specific antibodies confirmed that GSTalpha protein, but not GSTmu or GSTpi, was induced in cells treated with isoimperatorin. Reporter gene analysis using an antioxidant response element (ARE) containing construct and subcellular fractionation assays revealed that GSTalpha induction by isoimperatorin is associated with Nrf2/ARE activation. Moreover, ethoxyresorufin-O-deethylase assays showed that isoimperatorin (2 uM) completely inhibited 3-methylchoranthrene-inducible CYP1A activity. These results indicate that isoimperatorin from Poncirus trifoliata Raf. possesses a potent hepatoprotective effect against AFB1, presumably through the induction of GSTalpha and the direct inhibition of CYP1A, and suggest that isoimperatorin should be considered a potential chemopreventive.
/EXPL THER/ CONTEXT: Ostericum koreanum (Maxim.) Kitagawa (Apiaceae) roots are traditionally used as an analgesic and antiulcer agent. However, the antiulcer potential of isoimperatorin isolated from O. koreanum has not yet been explored. AIM: To evaluate the antiulcer activity of isoimperatorin isolated from the roots of O. koreanum. MATERIALS AND METHODS: Isoimperatorin was isolated as cubic crystals by repeated column chromatography of the ethyl acetate fraction and structure was verified with 1H NMR, 13C NMR and high-resolution mass spectrometry (HRMS-FAB). The crystals obtained were analyzed with the single crystal X-ray method. The MTT assay was used to determine its cytotoxicity against chondrocytes at different concentrations (0.0-737.74 uM, 24 hr). The in vivo antiulcer activity of isoimperatorin (40 mg/kg) was determined against ethanol-, indomethacin- and pyloric ligation-induced ulcers in Sprague-Dawley rats. Furthermore, the effect of isoimperatorin (0.0-737.74 uM, 24 hr) on the expression of type II collagen in chondrocytes was determined using western blot method. The in vitro urease inhibitory activity of isoimperatorin (0-80 uM) and molecular docking was also performed against urease. RESULTS AND DISCUSSION: Isoimperatorin demonstrated significant inhibitory activity (IC50 36.43 uM) against urease as compared to the standard drug thiourea (IC50 33.57 uM) without cytotoxic effects. It provided 70.9%, 67.65% and 54.25% protection in ulcer models induced by ethanol, indomethacin and pyloric ligation, respectively. Isoimperatorin showed the highest expression level of type II collagen at 368.87 uM. The docking results confirmed strong binding affinity with the target protein. CONCLUSION: Isoimperatorin may be used to develop antiulcer drugs with decreased side effects.

C16H14O4

270.2800

270.089

482-45-1

Isoimperatorin-d6

68081

White to off-white solid powder

1.2±0.1 g/cm3

448.3±45.0 °C at 760 mmHg

109ºC

224.9±28.7 °C

0.0±1.1 mmHg at 25°C

1.606

3.88

0

4

3

20

436

0

IGWDEVSBEKYORK-UHFFFAOYSA-N

InChI=1S/C16H14O4/c1-10(2)5-7-19-16-11-3-4-15(17)20-14(11)9-13-12(16)6-8-18-13/h3-6,8-9H,7H2,1-2H3

4-(3-methylbut-2-enoxy)furo[3,2-g]chromen-7-one

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: This product requires protection from light (avoid light exposure) during transportation and storage.

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

Ethanol : ~8.33 mg/mL (~30.82 mM)
DMSO : ~2.5 mg/mL (~9.25 mM)

Solubility in Formulation 1: ≥ 0.83 mg/mL (3.07 mM) (saturation unknown) in 10% EtOH + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 8.3 mg/mL clear EtOH stock solution to 400 μL of PEG300 and mix evenly; then add 50 μL of Tween-80 to the above solution and mix evenly; then add 450 μL of normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 2: ≥ 0.83 mg/mL (3.07 mM) (saturation unknown) in 10% EtOH + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 8.3 mg/mL clear EtOH stock solution to 900 μL of corn oil and mix well.

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 (Please use freshly prepared in vivo formulations for optimal results.)