A pH-responsive dissociable mesoporous silica-based nanoplatform enabling efficient dual-drug co-delivery and rapid clearance for cancer therapy.

The balance between tumor accumulation and renal clearance has severely limited the efficacy of mesoporous silica-based drug nanocarriers in cancer therapy. Herein, a pH-responsive dissociable mesoporous silica-based nanoplatform with efficient dual-drug co-delivery, tumor accumulation and rapid clearance for cancer therapy is achieved by adjusting the wetting of the mesoporous silica surface. At pH 7.4, the synthesized spiropyran- and fluorinated silane-modified ultrasmall mesoporous silica nanoparticles (SP-FS-USMSN) self-assemble to form larger nanoclusters (denoted as SP-FS-USMSN cluster) via hydrophobic interactions, which can effectively co-deliver anticancer drugs, doxorubicin hydrochloride (Dox) and curcumin (Cur), based on the mesopores within SP-FS-USMSN and the voids among the stacked SP-FS-USMSN. At pH 4.5-5.5, the conformational conversion of spiropyran from a "closed" state to an "open" state causes the wetting of the SP-FS-USMSN surface, leading to the dissociation of the SP-FS-USMSN cluster for drug release and renal clearance. The in vitro and in vivo studies demonstrate that the Cur and Dox co-loaded SP-FS-USMSN cluster (Cur-Dox/SP-FS-USMSN cluster) possesses great combined cytotoxicity, and can accumulate into tumor tissue by its large size-favored EPR effect and potently suppress tumor growth in HepG2-xenografted mice. This research demonstrates that the SP-FS-USMSN cluster may be a promising drug delivery system for cancer therapy and lays the foundation for practical mesoporous silica-based nanomedicine designs in the future.

Study on preparation and controlled release in vitro of bergenin-amino polylactic acid polymer.

The efficacy of traditional tablets, drop pills and soft capsules of bergenin is far lower than expected. Therefore, bergenin was modified in this paper to connect with amino polylactic acid, a kind of biodegradable material, for chemical immobilization. The bergenin-amino PLA thus obtained was controllable with small molecular weight and excellent thermal stability. Its release in vitro could be extended with the increase in molecular weight. According to tests of biological compatibility and anti-tumor in vitro, bergenin-amino PLA at a proportion of 1 to 100 was characterized by better biological compatibility and lower cytotoxicity than control group at a concentration of 0.4 µ g/m L. The chemical immobilization of bergenin not only provides patients with an excellent way of drug administration but lays a good foundation for sustained drug release.

Green chemistry appended synthesis, metabolic stability and pharmacokinetic assessment of medicinally important chromene dihydropyrimidinones.

A green chemistry approach has been developed for the synthesis of chromene dihydropyrimidinone (CDHPM) using recyclable Fe/Al pillared clay catalyst. Pharmacokinetic parameters like aqueous solubility, lipophilicity, P-glycoprotein (P-gp) ATPase activity, permeability, plasma protein binding, red blood cell (RBC) partitioning, metabolic stability in liver microsomes and in silico computations have been studied for the most potent anticancer chromene dihydropyrimidinone hybrid 1. This compound exhibited low solubility, optimum lipophilicity, no P-gp inhibitory activity, intermediate permeability, high plasma protein binding, low RBC partitioning, acceptable metabolic stability in rat liver microsomes (RLM) as well as human liver microsomes (HLM) with transitional hepatic extraction ratio.

CFTR activity is enhanced by the novel corrector GLPG2222, given with and without ivacaftor in two randomized trials.

BACKGROUND: Several treatment approaches in cystic fibrosis (CF) aim to correct CF transmembrane conductance regulator (CFTR) function; the efficacy of each approach is dependent on the mutation(s) present. A need remains for more effective treatments to correct functional deficits caused by the F508del mutation. METHODS: Two placebo-controlled, phase 2a studies evaluated GLPG2222, given orally once daily for 29 days, in subjects homozygous for F508del (FLAMINGO) or heterozygous for F508del and a gating mutation, receiving ivacaftor (ALBATROSS). The primary objective of both studies was to assess safety and tolerability. Secondary objectives included assessment of pharmacokinetics, and of the effect of GLPG2222 on sweat chloride concentrations, pulmonary function and respiratory symptoms. RESULTS: Fifty-nine and 37 subjects were enrolled into FLAMINGO and ALBATROSS, respectively. Treatment-related treatment-emergent adverse events (TEAEs) were reported by 29.2% (14/48) of subjects in FLAMINGO and 40.0% (12/30) in ALBATROSS; most were mild to moderate in severity and comprised primarily respiratory, gastrointestinal, and infection events. There were no deaths or discontinuations due to TEAEs. Dose-dependent decreases in sweat chloride concentrations were seen in GLPG2222-treated subjects (maximum decrease in FLAMINGO: -17.6 mmol/L [GLPG2222 200 mg], p < 0.0001; ALBATROSS: -7.4 mmol/L [GLPG2222 300 mg], p < 0.05). No significant effects on pulmonary function or respiratory symptoms were reported. Plasma GLPG2222 concentrations in CF subjects were consistent with previous studies in healthy volunteers and CF subjects. CONCLUSIONS: GLPG2222 was well tolerated. Sweat chloride reductions support on-target enhancement of CFTR activity in subjects with F508del mutation(s). Significant improvements in clinical endpoints were not demonstrated. Observed safety results support further evaluation of GLPG2222, including in combination with other CFTR modulators. FUNDING: Galapagos NV. Clinical trial registration numbers FLAMINGO, NCT03119649; ALBATROSS, NCT03045523.

Pharmacokinetics of a novel microtubule inhibitor mHA11 in rats.

mHA11, a 2-amino-4-phenyl-4H-chromene-3-carboxylate analog, is a microtubule-targeting agent discovered by our group through the modification of the Bcl-2 inhibitor HA14-1. mHA11 exhibits cytotoxicities against tumor cells with nM IC50 values, whereas it has only a minimal effect on normal cells. We explored the plasma pharmacokinetics, tissue distribution, and excretion of mHA11 in rats using a liquid chromatography/tandem mass spectrometry (LC-MS/MS) method. Next, we identified the metabolites of mHA11 and assessed the influence of cytochrome P450 (CYP) isozymes on mHA11 metabolism. We also examined the in vitro stability in rat plasma and rat liver microsomes (RLMs), the blood-to plasma (B/P) ratio, and the inhibitory effect on CYP isozyme activities. After oral administration at 5, 15, and 45 mg/kg, mHA11 was absorbed and eliminated rapidly. There was a linear correlation between the area under the concentration-time curve (AUC0-∞) and the dose (R2 = 0.983). The bioavailability of mHA11 was 4.1% at the oral dose of 15 mg/kg mHA11 was extensively distributed in various tissues and exhibited a high penetration into the brain. No significant parent drug was detected in urine or bile, and only 0.74% was recovered in feces, whereas two demethylated metabolites, M1 and M2, were found in the urine and feces, and further studies showed that CYP2C19 primarily contributed to metabolites formation. mHA11 was stable in rat plasma but degraded significantly in RLMs; its B/P ratio was 1.05 in rat blood. In addition, mHA11 dose-dependently inhibited the activities of rat CYP isozymes, including CYP1A2, CYP2C6, CYP2C11, CYP2D2, CYP2E1 and CYP3A2. The present study is the first report on the disposition of mHA11 in rats and provides important data for further research and development of this inhibitor.

Natural Korean Medicine Dang-Gui: Biosynthesis, Effective Extraction and Formulations of Major Active Pyranocoumarins, Their Molecular Action Mechanism in Cancer, and Other Biological Activities.

Angelica gigas Nakai (AGN) is a crucial oriental medicinal herb that grows especially in Korea and the Far-East countries. It contains chemically active compounds like pyranocoumarins, polyacetylenes and essential oils, which might be useful for treatment of several chronic diseases. It has been used for centuries as a traditional medicine in Southeast Asia, but in Western countries is used as a functional food and a major ingredient of several herbal products. The genus Angelica is also known as 'female ginseng' due to its critical therapeutic role in female afflictions, such as gynecological problems. However, it is well-documented that the AGN pyranocoumarins may play vital beneficial roles against cancer, neurodisorders, inflammation, osteoporosis, amnesia, allergies, depression, fungi, diabetes, ischemia, dermatitis, reactive oxygen species (ROS) and androgen. Though numerous studies revealed the role of AGN pyranocoumarins as therapeutic agents, none of the reviews have published their molecular mechanism of action. To the best of our knowledge, this would be the first review that aims to appraise the biosynthesis of AGN's major active pyranocoumarins, discuss effective extraction and formulation methods, and detail the molecular action mechanism of decursin (D), decursinol angelate (DA) and decursinol (DOH) in chronic diseases, which would further help extension of research in this area.

Prostate Cancer Xenograft Inhibitory Activity and Pharmacokinetics of Decursinol, a Metabolite of Angelica gigas Pyranocoumarins, in Mouse Models.

We have previously shown that the ethanol extract of dried Angelica gigas Nakai (AGN) root exerts anticancer activity against androgen receptor (AR)-negative human DU145 and PC-3 prostate cancer xenografts and primary carcinogenesis in the transgenic adenocarcinoma of mouse prostate (TRAMP) model. The major pyranocoumarin isomers decursin (D) and decursinol angelate (DA), when provided at equi-molar intake to that provided by AGN extract, accounted for the inhibitory efficacy against precancerous epithelial lesions in TRAMP mice. Since we and others have shown in rodents and humans that D and DA rapidly and extensively convert to decursinol, here we tested whether decursinol might be an in vivo active compound for suppressing xenograft growth of human prostate cancer cells expressing AR. In SCID-NSG mice carrying subcutaneously inoculated human LNCaP/AR-Luc cells overexpressing the wild type AR, we compared the efficacy of 4.5[Formula: see text]mg decursinol per mouse with equi-molar dose of 6[Formula: see text]mg D/DA per mouse. The result showed that decursinol decreased xenograft tumor growth by 75% and the lung metastasis, whereas D/DA exerted a much less effect. Measurement of plasma decursinol concentration, at 3[Formula: see text]h after the last dose of respective dosing regimen, showed higher circulating level in the decursinol-treated NSG mice than in the D/DA-treated mice. In a subsequent single-dose pharmacokinetic experiment, decursinol dosing led to 3.7-fold area under curve (AUC) of plasma decursinol over that achieved by equi-molar D/DA dosing. PK advantage notwithstanding, decursinol represents an active compound to exert in vivo prostate cancer growth and metastasis inhibitory activity in the preclinical model.

Structure-Function Relationship Studies In Vitro Reveal Distinct and Specific Effects of Long-Chain Metabolites of Vitamin E.

SCOPE: Cytochrome-dependent metabolism of vitamin E initially forms the long-chain metabolites (LCM) 13'-hydroxychromanols (13'-OH) and 13'-carboxychromanols (13'-COOH), which occur in human blood. Little is known about their biological functions. MATERIAL AND RESULTS: A structure-activity relationship study using α- and δ-tocopherol (TOH), their LCM (α-13'-OH, δ-13'-OH, α-13'-COOH, and δ-13'-COOH) and representatives of their substructures (α-carboxyethylhydroxychromanol and pristanic acid) is performed to unravel critical structural elements of the LCM for biological activity. Prominent effects are mediated by α- and δ-LCM, as scavenger receptor cluster of differentiation 36 (CD36) expression is induced in human THP-1 macrophages and lipopolysaccharide-stimulated inducible nitric oxide synthase (iNos) expression is inhibited in murine RAW264.7 macrophages, while the other molecules are less or not effective. CONCLUSION: The LCM effects depend on the presence of the chromanol ring system and on the modification of the side-chain but not on the substitution pattern of the chromanol ring. Therefore, it can be concluded that for mediation of effects by LCM the entire molecule is needed and that the effects are specific. We propose the LCM of the micronutrient vitamin E as a new class of regulatory metabolites, but further studies are needed to corroborate this hypothesis.

Discovery of a series of 8-(1-phenylpyrrolidin-2-yl)-6-carboxamide-2-morpholino-4H-chromen-4-one as PI3Kß/δ inhibitors for the treatment of PTEN-deficient tumours.

Attempts to lock the active conformation of compound 4, a PI3Kß/δ inhibitor (PI3Kß cell IC50 0.015µM), led to the discovery of a series of 8-(1-phenylpyrrolidin-2-yl)-6-carboxamide-2-morpholino-4H-chromen-4-ones, which showed high levels of potency and selectivity as PI3Kß/δ inhibitors. Compound 10 proved exquisitely potent and selective: PI3Kß cell IC50 0.0011µM in PTEN null MDA-MB-468 cell and PI3Kδ cell IC50 0.014µM in Jeko-1 B-cell, and exhibited suitable physical properties for oral administration. In vivo, compound 10 showed profound pharmacodynamic modulation of AKT phosphorylation in a mouse PTEN-null PC3 prostate tumour xenograft after a single oral dose and gave excellent tumour growth inhibition in the same model after chronic oral dosing. Based on these results, compound 10 was selected as one of our PI3Kß/δ preclinical candidates.

Radiolabeling and initial biological evaluation of [18F]KBM-1 for imaging RAR-α receptors in neuroblastoma.

Retinoic acid receptor alpha (RAR-α) plays a significant role in a number of diseases, including neuroblastoma. Children diagnosed with high-risk neuroblastoma are treated13-cis-retinoic acid, which reduces risk of cancer recurrence. Neuroblastoma cell death is mediated via RAR-α, and expression of RAR-α is upregulated after treatment. A molecular imaging probe that binds RAR-α will help clinicians to diagnose and stratify risk for patients with neuroblastoma, who could benefit from retinoid-based therapy. In this study, we report the radiolabeling, and initial in vivo evaluation of [18F]KBM-1, a novel RAR-α agonist. The radiochemical synthesis of [18F]KBM-1 was carried out through KHF2 assisted substitution of [18F]- from aryl-substituted pinacolatoesters-based retinoid precursor. In vitro cell uptake assay in human neuroblastoma cell line showed that the uptake of [18F]KBM-1 was significantly inhibited by all three blocking agents (KBM-1, ATRA, BD4) at all the selected incubation times. Standard biodistribution in mice bearing neuroblastoma tumors demonstrated increased tumor uptake from 5min to 60min post radiotracer injection and the uptake ratios for target to non-target (tumor: muscle) increased 2.2-fold to 3.7-fold from 30min to 60min post injection. Tumor uptake in subset of 30min blocking group was 1.7-fold lower than unblocked. These results demonstrate the potential utility of [18F]KBM-1 as a RAR-α imaging agent.

Pharmacology and toxicology of the novel investigational agent Cantrixil (TRX-E-002-1).

PURPOSE: Recurrent, chemo-resistant ovarian cancer is thought to be due to a subgroup of slow-growing, drug-resistant cancer cells with stem-like properties and a high capacity for tumour repair. Cantrixil targets this sub-population of cells and is being developed as an intraperitoneal therapy to be used as first-line therapy in combination with carboplatin for epithelial ovarian cancer. The studies presented here justify further development. METHODS: A GLP dog CV study using a 4 × 4 Latin Square Crossover study was conducted using telemetric ECG recordings from dogs post IP administration to assess for cardiac abnormalities. Mutagenic potential was assessed using the bacterial reverse mutation assay. Clastogenicity was assessed by determining micronuclei formation in the bone marrow of SPF Arc(S) Swiss mice dosed at clinical concentrations. TRX-E-002-1 toxicology was evaluated in GLP-compliant MTD and 28-day repeat-dose studies in rats and dogs. RESULTS: In vitro TRX-E-002-1 has potent cytotoxic activity against human cancer cells including CD44+/MyD88+ ovarian cancer stem cells. TRX-E-002-1 increased phosphorylated c-Jun levels in these cancer cells resulting in caspase-mediated apoptosis. In vivo, Cantrixil was active in a model of disseminated ovarian cancer as a monotherapy and in combination with Cisplatin. Cantrixil was active as maintenance therapy in a model of drug-resistant, recurrent ovarian cancer and in an orthotopic model of pancreatic cancer. CONCLUSIONS: In animals, this clinical formulation and route of administration of Cantrixil demonstrated acceptable activity, safety pharmacology, genotoxicity and toxicology profile and constituted a successful Investigational New Drug application to the US Food and Drug Administration.

In vitro, ex vivo and in vivo characterization of PLGA nanoparticles loading pranoprofen for ocular administration.

Pranoprofen (PF) is a NSAID considered as a safe anti-inflammatory treatment for strabismus and/or cataract surgery. The drug has been formulated in poly (lactic/glycolic) acid (PLGA) nanoparticles (PF-F1NPs with cPF 1.5mg/mL, PF-F2NPs with cPF 1mg/mL) produced by solvent displacement technique and tested the in vitro cytotoxicity, ex vivo corneal permeation, in vivo ocular tolerance and in vivo anti-inflammatory efficacy of PF-F1NPs, PF-F2NPs, in comparison to eye drops conventional dosage form (Oftalar(®), PF 1mg/mL) and free drug solution (PF dissolved in PBS, 1.5mg/mL). The mean particle size of both formulations was around 350nm, with polydispersity index below 0.1, and a net negative charge of -7.41mV and -8.5mV for PF-F1NPs and PF-F2NPs, respectively. Y-79 human retinoblastoma cell line was used to evaluate the cytotoxicity of PF-F1NPs and PF-F2NPs, which were compared to blank NPs and free drug solution (PF dissolved in PBS, 1.5mg/mL). Concentrations up to 75µg/mL exhibited no toxicity to Y-79 cells, whereas at 150µg/mL a decrease of about 80% on the cell viability was observed after exposing the cells to PF-F1NPs. When treating the Y-79 cells with concentrations of PF-F2NPs between 1µg/mL to 100µg/mL, the cell viability was similar to control values after 24h and 48h of exposure. An ex vivo corneal permeation study was carried out in New Zealand rabbits. A very similar profile has been observed for the permeation of PF through the cornea when administered as eye drops and as free drug solution, which was kept much lower in comparison to PF-NPs formulations. The permeated amount of PF from the PF-F1NPs was slightly smaller than from PF-F2NPs, attributed to the increase of viscosity of the formulations with the increase of cPVA concentration. New Zealand white rabbits were also used to evaluate the irritancy of PF-F1NPs and PF-F2NPs, which demonstrated to be well-tolerated to the eye (i.e. the mean total score (MTS) was 0). PF-F2NPs exhibited the highest QP (amounts of PF permeated in the cornea) and significantly reduced the ocular edema compared to the tested formulations. The QR (amounts of PF retained in the cornea) of the PF-F1NPs was greater than that obtained for PF-F2NPs.

PEGylated chitosan nanoparticles potentiate repurposing of ormeloxifene in breast cancer therapy.

AIM: Development and optimization of ormeloxifene-loaded PEGylated chitosan nanoparticles (CNPs) for enhancing its literature profound therapeutic activity against breast cancer. METHODS: CNPs were prepared by ionotropic gelation method and characterized. RESULTS: Optimized formulation (CNPs10) had average 304 nm particle size with 0.247 polydispersity index and spherical shape with +31 mV surface charge. CNPs10 had 88.37% entrapment efficiency and 20.93% loading efficiency. CNPs10 demonstrated dose-dependent enhancement in cytotoxicity, cellular uptake, apoptosis, disruption of mitochondrial membrane potential and activation of caspase-3 in breast cancer MDA-MB-231 and MCF-7 cells over free ormeloxifene. In vivo studies divulged improved pharmacokinetic parameters, reduced toxicity, suppressed tumor burden and increased survival in CNPs10-treated female Sprague-Dawley rats. CONCLUSION: PEGylated CNPs enhanced anticancer activity of ormeloxifene.

Differentiation of skeletal osteogenic progenitor cells to osteoblasts with 3,4-diarylbenzopyran based amide derivatives: Novel osteogenic agents.

A series of 3,4-diarylbenzopyran based amide derivatives was synthesized and evaluated for osteogenic activity in in vitro and in vivo models of osteoporosis. Compounds 17a, 21b-c and 22a-b showed significant osteogenic activity in osteoblast differentiation assay. Among the synthesized compounds, 22b was identified as lead molecule which showed significant osteogenic activity at 1 pM concentration in osteoblast differentiation assay and at 1 mg kg(-1) body weight dose in estrogen deficient balb/c mice model. In vitro bone mineralization and expression of osteogenic marker genes viz BMP-2, RUNX-2, OCN, and collagen type 1 further confirmed the osteogenic potential of 22b. Gene expression study for estrogen receptor α and ß (ER-α and ER-ß) in mouse calvarial osteoblasts (MCOs) unveiled that possibly 22b exerted osteogenic efficacy via activation of Estrogen receptor-ß preferentially. In vivo pharmacokinetic, estrogenicity and acute toxicity studies of 22b showed that it had good bioavailability and was devoid of uterine estrogenicity at 1 mg kg(-1) and inherent toxicity up to 1000 mg kg(-1) body weight dose respectively.

In Vitro Bioaccessibility, Human Gut Microbiota Metabolites and Hepatoprotective Potential of Chebulic Ellagitannins: A Case of Padma Hepaten® Formulation.

Chebulic ellagitannins (ChET) are plant-derived polyphenols containing chebulic acid subunits, possessing a wide spectrum of biological activities that might contribute to health benefits in humans. The herbal formulation Padma Hepaten containing ChETs as the main phenolics, is used as a hepatoprotective remedy. In the present study, an in vitro dynamic model simulating gastrointestinal digestion, including dialysability, was applied to estimate the bioaccessibility of the main phenolics of Padma Hepaten. Results indicated that phenolic release was mainly achieved during the gastric phase (recovery 59.38%-97.04%), with a slight further release during intestinal digestion. Dialysis experiments showed that dialysable phenolics were 64.11% and 22.93%-26.05% of their native concentrations, respectively, for gallic acid/simple gallate esters and ellagitanins/ellagic acid, in contrast to 20.67% and 28.37%-55.35% for the same groups in the non-dialyzed part of the intestinal media. Investigation of human gut microbiota metabolites of Padma Hepaten and pure ChETs (chebulinic, chebulagic acids) established the formation of bioactive urolithins (A, B, C, D, M5). The fact of urolithin formation during microbial transformation from ChETs and ChET-containing plant material was revealed for the first time. Evaluation of the protective effect of ChETs colonic metabolites and urolithins on tert-butyl hydroperoxide (t-BHP)-induced oxidative injury in cultured rat primary hepatocytes demonstrated their significant reversion of the t-BHP-induced cell cytotoxicity, malonic dialdehyde production and lactate dehydrogenase leakage. The most potent compound was urolithin C with close values of hepatoprotection to gallic acid. The data obtained indicate that in the case of Padma Hepaten, we speculate that urolithins have the potential to play a role in the hepatic prevention against oxidative damage.

Rapid quantitative analysis of ormeloxifene and its active metabolite, 7-desmethyl ormeloxifene, in rat plasma using liquid chromatography-tandem mass spectrometry.

Ormeloxifene (ORM) is a non-steroidal, selective estrogen receptor modulator used as a once a week oral contraceptive and is intended for long-term clinical use by females. Therefore, a simple, sensitive and rapid LC-MS/MS method was developed and validated for simultaneous quantification of ORM and its active metabolite (7-desmethyl ormeloxifene, 7-DMO) in rat plasma. Also, the method was partially validated in human plasma. Chromatographic separation was achieved on Discovery HS C-18 column (5µm, 50×4.6mm) with mobile phase [acetonitrile: aqueous ammonium acetate (0.01M) buffer (85: 15, %v/v)] at a flow rate of 0.8mL/min. The calibration curve was linear (r≥0.99) for a concentration range of 0.78-100ng/mL for both the analytes. The precision (%RSD; ORM, 1.3 to 13.4; 7-DMO, 3.1 to 15.0) and accuracy (%bias; ORM, -13.8 to 12.5; 7-DMO, -10.6 to 6.8) in both rat and human plasma were within the acceptable limits. The recovery for ORM and 7-DMO was always >79.1% and >72.9%, respectively. Both the analytes were found stable in rat plasma even after 30 days of storage at -80°C and on being subjected to three freeze-thaw cycles. The method has not only short run time (3.5min) but requires a low plasma sample volume (20µL) and is the first reported LC-MS/MS method for simultaneous quantification of the marketed drug known as centchroman (INN: ormeloxifene) and the metabolite 7-DMO in plasma. The method was applied to evaluate drug-drug interaction of ORM with the commonly prescribed antidepressant drug sertraline using serial sampling in rats.

The natural compound chebulagic acid inhibits vascular endothelial growth factor A mediated regulation of endothelial cell functions.

Vascular endothelial growth factor A (VEGFA) plays an important role in tumour angiogenesis and its angiogenic action is mainly mediated through its VEGF receptor 2 (VEGFR-2). Therefore drugs targeting VEGFA/VEGFR-2 are being presently used in the clinics for treatment of several types of solid malignant tumours. We here in report that low dose of chebulagic acid (CA), a hydrolysable tannin found in myrobalan fruits can inhibit VEGFA induced vascular permeability, endothelial cell proliferation, migration, tube formation and thereby, angiogenesis by suppressing VEGFR-2 phosphorylation. CA may thus be an effective and useful natural inhibitor of VEGFA mediated angiogenesis.

Blood pressure decrease in spontaneously hypertensive rats folowing renal denervation or dopamine ß-hydroxylase inhibition with etamicastat.

Overactivity of the sympathetic nervous system has an important role in the development and progression of arterial hypertension. Catheter-based renal nerve ablation for the treatment of drug-resistant hypertension has recently been developed. An alternative strategy for the modulation of sympathetic nerve function is to reduce the biosynthesis of noradrenaline (NA) by inhibiting dopamine ß-hydroxylase (DßH), the enzyme that catalyzes the conversion of dopamine (DA) to NA in the sympathetic nerves. Renal denervation (RDN) surgery was performed in spontaneously hypertensive rats (SHR) to evaluate the effect of RDN on the DA and NA levels and on blood pressure over a 28-day period. The selective peripheral DßH inhibitor etamicastat (30 mg kg (-1)day(-1)) was administered to another cohort of SHR. RDN and etamicastat treatment had no effect on the renal function, as assessed by measuring the water balance response, renal function and urinary electrolyte levels. RDN significantly decreased the systolic blood pressure (SBP) and the diastolic blood pressure (DBP). A gradual return of the SBP and the DBP to the high baseline levels was observed over time. Conversely, treatment with etamicastat resulted in a significant decrease in the SBP and the DBP at all time points. On the last day of the assessment, NA levels in renal tissue were significantly decreased in both RDN and etamicastat-treated groups. In contrast, the NA levels in the left ventricle were decreased only in the etamicastat-treated group. Thus, RDN produces transitory decreases in blood pressure, whereas prolonged downregulation of sympathetic drive with the DßH inhibitor etamicastat results in a sustained decrease in the SBP and the DBP.

Cardiovascular safety pharmacology profile of etamicastat, a novel peripheral selective dopamine-ß-hydroxylase inhibitor.

Etamicastat, a peripheral reversible dopamine-ß-hydroxylase inhibitor, blocked the hERG current amplitude with an IC50 value of 44.0µg/ml in HEK 293 cells. At 0.3 and 3µg/ml, etamicastat had no effects on the action potential (AP) in male dog Purkinje fibers. At 30µg/ml, etamicastat significantly affected resting membrane potential (+4%), AP amplitude (-4%), AP duration at 60% (-14%) and AP duration at 90% (+5%) repolarization, and AP triangulation (+79%). In the telemetered conscious male dog, etamicastat (up to 20mg/kg) had no effects on arterial blood pressure, heart rate and the PR interval. At 10 and 20mg/kg, the QTc interval was slightly prolonged (8-9% max, P<0.05). No arrhythmia or other changes in the morphology of the ECG were observed. The maximum observed plasma concentrations (Cmax) of etamicastat (i.e. 3h post-administration) were 1.4 and 3.7µg/ml at 10 and 20mg/kg, respectively. No deleterious effects, including ECG disturbance were observed in male and female dogs dosed by gavage with etamicastat (up to 20mg/kg/day) for 28 days. Mean plasma Cmax etamicastat levels ranged between 2.4 and 6.3µg/ml on Day 1 and Day 28 of treatment, respectively. It is concluded that the blockade of the delayed rectifier potassium channels by etamicastat together with the QTc interval prolongation observed in conscious dogs can be considered as modest with respect to the measured plasmatic concentrations. These findings suggest that etamicastat is not likely to prolong the QT interval at therapeutic doses (~0.2µg/ml).

Single oral dose pharmacokinetics of decursin and decursinol angelate in healthy adult men and women.

UNLABELLED: The ethanol extract of Angelica gigas Nakai (AGN) root has promising anti-cancer and other bioactivities in rodent models. It is currently believed that the pyranocoumarin isomers decursin (D) and decursinol angelate (DA) contribute to these activities. We and others have documented that D and DA were rapidly converted to decursinol (DOH) in rodents. However, our in vitro metabolism studies suggested that D and DA might be metabolized differently in humans. To test this hypothesis and address a key question for human translatability of animal model studies of D and DA or AGN extract, we conducted a single oral dose human pharmacokinetic study of D and DA delivered through an AGN-based dietary supplement Cogni.Q (purchased from Quality of Life Labs, Purchase, NY) in twenty healthy subjects, i.e., 10 men and 10 women, each consuming 119 mg D and 77 mg DA from 4 vegicaps. Analyses of plasma samples using UHPLC-MS/MS showed mean time to peak concentration (Tmax) of 2.1, 2.4 and 3.3 h and mean peak concentration (Cmax) of 5.3, 48.1 and 2,480 nmol/L for D, DA and DOH, respectively. The terminal elimination half-life (t1/2) for D and DA was similar (17.4 and 19.3 h) and each was much longer than that of DOH (7.4 h). The mean area under the curve (AUC0-48h) for D, DA and DOH was estimated as 37, 335 and 27,579 h∙nmol/L, respectively. Gender-wise, men absorbed the parent compounds faster and took shorter time to reach DOH peak concentration. The human data supported an extensive conversion of D and DA to DOH, even though they metabolized DA slightly slower than rodents. Therefore, the data generated in rodent models concerning anti-cancer efficacy, safety, tissue distribution and pharmacodynamic biomarkers will likely be relevant for human translation. TRIAL REGISTRATION: ClinicalTrials.gov NCT02114957.