Pharmacogenetic effects of regulatory nuclear receptors (PXR, CAR, RXRα and HNF4α) on docetaxel disposition in Chinese nasopharyngeal cancer patients

Purpose

This exploratory study was aimed at elucidating the pharmacogenetics of regulatory nuclear receptors (PXR, CAR, RXRα and HNF4α) and their implications on docetaxel pharmacokinetics and pharmacodynamics in local Chinese nasopharyngeal cancer patients.

Methods

A total of 59 single nucleotide polymorphisms (SNPs), including tag-SNPs and functionally relevant SNPs of the genes encoding these regulatory nuclear receptors (PXR/NR1I2, CAR/NR1I3, RXRα/NR2B1 and HNF4α/NR2A1), were profiled in the patients enrolled in our study by direct sequencing (N?=?50). The generalized linear model was employed to estimate the haplotypic effects on the pharmacokinetics and pharmacodynamics of the patients.

Results

The pharmacokinetic profiles of docetaxel in these patients were characterized by marked interindividual variability, with approximately four- to sixfold variations observed in C_max, AUC_0-∞ and CL. Individual SNP association tests revealed that polymorphisms in NR2B1 and NR2A1 were significantly correlated with altered docetaxel pharmacokinetics. Subsequent haplotype association analysis identified the NR2B1 LD block 2 AG haplotype [*+4458G>A(rs3132291) and *+4988A>G(rs4842198)] to be significantly associated with altered pharmacokinetics, in which patients carrying two copies of the AG haplotype had approximately a 20 % decreased C_max and AUC_0-∞ and a 21 % increased CL compared to those who carried only one copy or no copies of the haplotype. A number of SNPs in NR1I2, NR1I3, NR2B1 and NR2A1 were also associated with a significant decrease in blood counts from baseline. No haplotype was found to exert any effects on the pharmacodynamics parameters.

Conclusions

The present exploratory study identified several SNPs in the genes encoding regulatory nuclear receptors which may account for the interpatient variability in docetaxel pharmacokinetics and pharmacodynamics. These findings highlight the important role of regulatory nuclear receptors on the disposition of docetaxel.     

Microwave-accelerated preparation and analytical characterization of 5-ethoxy-N,N-dialkyl-[α,α,β,β-H(4) ]- and [α,α,β,β-D(4) ]-tryptamines

The increased interest in N,N-dialkyl tryptamines is a reflection of their diverse range of biologically active properties. Deuterated derivatives are of interest for use as internal standards in bioanalytical or pharmacological assays. The present study reports on the synthesis of twelve novel 5-ethoxy-N,N-dialkyl-[α,α,β,β-H(4) ]-tryptamines and their [α,α,β,β-D(4) ]-counterparts following the Speeter and Anthony procedure. The normally time-consuming reduction step was carried out in 5 min under microwave-accelerated conditions. Good yields were obtained using tetrahydrofuran as the solvent at 150 °C. The resulting 24 tryptamines have been characterized by 1D/2D nuclear magnetic resonance spectroscopy and gas chromatography ion trap mass spectrometry. Differential fragmentation of side-chain-related iminium ions has been observed as a key principle. Because many N,N-dialkyltryptamines are available outside of traditional pharmaceutical supply chains as so-called 'research chemicals', the availability, as standards, of these new N,N-dialkyltryptamines will aid in identifiying novel tryptamines arising from these other souces. They should therefore be of immediate value within forensic, research, and public health contexts.     

Poly-α,β-dl-Aspartyl-l-Cysteine: A Novel Nanomaterial Having a Porous Structure, Special Complexation Capability for Pb(II), and Selectivity of Removing Pb(II)

Poly-α,β-dl-aspartic acid is known as a green chelant of various metal ions. To provide a novel nanochelant for treating Pb(II) poisoning, poly-α,β-dl-aspartic acid was modified with l-Cys to form poly-α,β-dl-aspartyl-l-cysteine (PDC; MW, 27273). dl-Asp was converted into polysuccinimide through a thermal polycondensation, and the amidation of polysuccinimide with l-Cys provided PDC. In water, PDC formed various porous nanospecies. In the mouse lead intoxication model, both intraperitoneal and oral administration of PDC (0.1, 1.0, and 10.0 nmol/kg) dose dependently removed Pb(II) accumulated in the organ, bone, and blood. PDC did not remove the essential metals including Cu(2+), Fe(2+), Mn(2+), Zn(2+), and Ca(2+) of the treated mice. The porous feature and size of the pH- and concentration-dependent nanospecies of PDC benefited the removal of Pb(II).     

Hepatocellular hypertrophy and cell proliferation in Sprague-Dawley rats from dietary exposure to potassium perfluorooctanesulfonate results from increased expression of xenosensor nuclear receptors PPARα and CAR/PXR

The present study investigated the potential role for activation of PPARα and CAR/PXR by potassium PFOS (K? PFOS) with respect to the etiology of hepatic hypertrophy and hepatocellular adenoma in rats. Male Sprague-Dawley rats were fed K? PFOS (20 or 100 ppm) for either 1, 7, or 28 days. Wyeth 14,643 (Wy 14,643, 50 ppm) and phenobarbital (PB, 500 ppm) were the controls for PPARα and CAR/PXR activation, respectively. Measurements included: plasma ALT, AST, cholesterol, triglycerides, and glucose; liver protein and DNA content; liver activities of palmitoyl CoA oxidase (ACOX), Cyp4A, CYP2B, and CYP3A; induction of liver CYP4A1, CYP2E1, CYP2B1/2, and CYP3A1 proteins (SDS-PAGE and Western blots); liver and thyroid microscopic histopathology, apoptotic index, and cell proliferation index. Terminal body weight was decreased by K? PFOS (100 ppm) and Wy 14,643. All test-compound treatments increased liver weight. Plasma lipids were decreased by both PFOS and Wy 14,643. After treatment for 1 day, K? PFOS (100 ppm), PB, and Wy 14,643 increased mean hepatic DNA concentration and total hepatic DNA, and total DNA remained elevated after treatment for 7 days and 28 days (PB and Wy 14,643 only). Hepatic P450 concentration was elevated after 7 and 28 days by K? PFOS and by PB. K? PFOS and Wy 14,643 increased liver activities of ACOX and CYP4A as well as increased liver CYP4A1 protein. By 28 days of treatment, K? PFOS and PB increased liver activities of CYP2B and CYP3A as well as increased liver CYP2B1/2 and CYP3A1 proteins, and Wy 14,643 increased CYP2B enzyme activity to a slight extent. All test compounds increased the liver cell proliferative index and decreased the liver apoptotic index. No histological changes of the thyroid were noted; however, PB and WY increased thyroid follicular cell proliferation index (seven-day treatment only), while K? PFOS did not. The thyroid follicular cell apoptotic index did not differ between groups. The hepatomegaly and hepatocellular adenoma observed after dietary exposure of Sprague-Dawley rats to K? PFOS likely are due to the increased expression of xenosensor nuclear receptors PPARα and CAR/PXR. Given the markedly lower or absent response of human hepatocytes to the proliferative stimulus from activation of PPARα and CAR/PXR, the hepatocellular proliferative response from activation of these receptors by PFOS observed in rats is not expected to be of human relevance.     

Note: Capitulatin B,A new eudesmane derivative from Curculigo capitulata,and revised assignment of 13C NMR data of 6α,15α-epoxy-1β,4β-dihydroxyeudesmane

A new eudesmane derivative named capitulatin B (1) along with 6α,15α-epoxy-1β,4β-dihydroxyeudesmane (2) has been isolated from the rhizomes of Curculigo capitulata. The structure of compound 1 was established as 4α,6α-epoxy-1β-hydroxy-4β-methyleudesmane, and the ¹³C NMR data of compound 2 was reassigned on the basis of the spectral data, including 1D and 2D NMR (HMQC, HMBC, COSY, ROESY).     

A combined,bioidentical, oral, 17β-estradiol and progesterone capsule for the treatment of moderate to severe vasomotor symptoms due to menopause

ABSTRACT

Introduction: Many women seek treatment to alleviate menopausal vasomotor symptoms (VMS). Numerous women use combination compounded hormone therapy (CHT) to achieve the benefits of estrogen/progesterone for endometrial protection. TX-001HR is a combination of bioidentical 17β-estradiol (E2) and progesterone (P4) in a single capsule designed for continuous daily use to treat moderate to severe VMS.

Areas covered: This drug profile describes the efficacy and safety of 4 doses of this E2/P4 (mg/mg: 1/100, 0.5/100, 0.5/50, 0.25/50) for treating moderate to severe VMS in menopausal woman with a uterus.

Expert opinion: In REPLENISH (NCT01942668), the two highest doses of TX-001HR significantly reduced VMS frequency and severity at 4 and 12 weeks versus placebo (co-primary endpoints); all doses met the primary endpoint of endometrial safety. Rates of amenorrhea were high and improved over time; the Menopause Quality of Life and Medical Outcomes Study-Sleep instruments improved with E2/P4. TX-001HR was well tolerated and had no clinically significant impact on vital signs, metabolic or coagulation parameters, or breast safety. The combination bioidentical E2/P4 capsule (1 mg/100 mg dose was FDA-approved as Bijuva in October 2018) may provide a safe, effective, rigorously studied alternative for women with a uterus who prefer CHT for relief of VMS.     

Synthesis, anti-inflammatory, and cytotoxicity evaluation of 9,10-dihydroanthracene-9,10-α,β-succinimide and bis-succinimide derivatives

9,10-Dihydroanthracene-9,10-α,β-succinimide derivatives 4a–e and bis-succinimide derivatives 6a–e have been synthesized by grinding 9,10-dihydroanthracene-9,10-α,β-succinic anhydride 2 with various mono 3a–e and diamines 5a–e in quantitative yields. All the target compounds were fully characterized by spectrometric and spectroscopic means. Compounds 4a–e, 6a–e and recently reported compounds 4f–p were screened for anti-inflammatory and for cytotoxicity against five human cancer cell lines: T47D, NCI H-522, HCT-15, PA1, and HepG-2. Compounds 4e, 4i, 4j, and 4p exhibited good anti-inflammatory activity and compounds with interesting cytotoxic profile were 4c, 6e (T47D); 4e, 4o (NCI H-522); 4n (HCT-15); 4e, 4h, 4o (PA1); and 4a, 4e, 4f, 4i, 4o (HepG-2).     

Synthesis and in vivo lead detoxification evaluation of Poly-α,β-dl-aspartyl-l-methionine

To increase the metal selectivity of polyaspartic acid, a so-called green chelant, poly-α,β-dl-aspartyl-l-methionine (PDM) was synthesized as a novel lead chelating agent. The phosphoric acid (80%) catalyzed thermal poly condensation of dl-aspartic acid provided poly succinimide, which was amidated with l-methionine to form PDM (MW: 29161). At the doses of 0.1, 1.0, and 10.0 nmol/kg, either by intraperitoneal injection (i.p.) or oral administration, PDM removed Pb from the spleens, hearts, and kidneys of mice, especially dose-dependently decreasing the accumulation of Pb in the brains, livers, and femurs of the mice, and did not interfere with the essential metals, including Cu, Fe, Mn, and Ca. Even at the dose of 0.1 nmol/kg, the i.p. injection of PDM removed Pb from the spleens, hearts, and kidneys of mice and increased the amount of urinary volume and urinary Pb, and the amount of fecal matter and the amount of fecal Pb, resulting in effective removal of Pb from the body of mice given Pb by i.p. injection. Our findings revealed that in aqueous solution PDM formed diverse nanospecies.     

Hepatocellular hypertrophy and cell proliferation in Sprague–Dawley rats following dietary exposure to ammonium perfluorooctanoate occurs through increased activation of the xenosensor nuclear receptors PPARα and CAR/PXR

Ammonium perfluorooctanoate (APFO), a processing aid used in the production of fluoropolymers, produces hepatomegaly and hepatocellular hypertrophy in rodents. In mice, APFO-induced hepatomegaly is associated with increased activation of the xenosensor nuclear receptors, PPARα and CAR/PXR. Although non-genotoxic, chronic dietary treatment of Sprague–Dawley (S–D) rats with APFO produced an increase in benign tumours of the liver, acinar pancreas, and testicular Leydig cells. Most of the criteria for establishing a PPARα-mediated mode of action for the observed hepatocellular tumours have been previously established with the exception of the demonstration of increased hepatocellular proliferation. The present study evaluates the potential roles for APFO-induced activation of PPARα and CAR/PXR with respect to liver tumour production in the S-D rat and when compared to the specific PPARα agonist, 4-chloro-6-(2,3-xylidino)-2-pyrimidinylthioacetic acid (Wy 14,643). Male S-D rats were fed APFO (300 ppm in diet) or Wy 14,643 (50 ppm in diet) for either 1, 7, or 28 days. Effects of treatment with APFO included: decreased body weight; hepatomegaly, hepatocellular hypertrophy, hepatocellular hyperplasia (microscopically and by BrdU labelling index), and hepatocellular glycogen loss; increased activation of PPARα (peroxisomal β-oxidation and microsomal CYP4A1 protein); decreased plasma triglycerides, cholesterol, and glucose; increased activation of CAR (CYP2B1/2 protein) and CAR/PXR (CYP3A1 protein). Responses to treatment with Wy 14,643 were consistent with increased activation of PPARα, specifically: increased CYP4A1 and peroxisomal β-oxidation; increased hepatocellular hypertrophy and cell proliferation; decreased apoptosis; and hypolipidaemia. With the exception of decreased apoptosis, the effects observed with Wy 14,643 were noted with APFO, and APFO was less potent. These data clearly demonstrate an early hepatocellular proliferative response to APFO treatment and suggest that the hepatomegaly and tumours observed after chronic dietary exposure of S-D rats to APFO likely are due to a proliferative response to combined activation of PPARα and CAR/PXR. This mode of action is unlikely to pose a human hepatocarcinogenic hazard.     

Comparison of naltrexone, 6α-naltrexol, and 6β-naltrexol in morphine-dependent and in nondependent rhesus monkeys

Rationale Some opioid receptor ligands that appear to be neutral antagonists can have inverse agonist activity under conditions of increased constitutive activity (e.g., agonist treatment). Objectives This study compared the opioid receptor antagonist naltrexone and its metabolites 6α-naltrexol and 6β-naltrexol in nondependent and morphine-dependent monkeys to see whether their potencies varied according to drug treatment and, presumably, to differences in constitutive activity of μ opioid receptors. Results In monkeys (n = 4) receiving 3.2 mg/kg per day of morphine and discriminating 0.0178 mg/kg naltrexone, naltrexone and each metabolite increased responding on the naltrexone lever in a dose-related manner with naltrexone being 8- and 71-fold more potent than 6α- and 6β-naltrexol, respectively. After 27 h of no-morphine treatment, monkeys responded on the naltrexone lever, and this effect was reversed by morphine. Naltrexone and each metabolite prevented morphine reversal of naltrexone-lever responding, and their rank order potency was the same as their substitution for naltrexone; however, the potency between naltrexone and each metabolite was slightly greater in morphine-dependent as compared to morphine-deprived monkeys. In a separate group (n = 3) of nondependent monkeys discriminating 1.78 mg/kg of morphine, all three compounds antagonized morphine with the same potency as in the reversal study (morphine-dependent monkeys), with Schild analyses showing no difference in apparent affinities (pA ₂) between nondependent and morphine-dependent monkeys. Conclusion Naltrexone and 6α- and 6β-naltrexol have qualitatively similar effects, and their potencies do not vary markedly with opioid treatment, suggesting that under these conditions, they do not vary with regard to inverse agonism.     

Binding ofβ-adrenoceptor blocking drugs to human serum albumin,to α1-acid glycoprotein and to human serum

Summary The binding of 8 -adrenergic blocking drugs to human serum albumin, to ₁-acid glycoprotein and to serum from normal volunteers and from patients with rheumatoid arthritis was studied. Protein binding was determined in vitro using equilibrium dialysis of labelled drug at 25° C. Oxprenolol and propranolol were highly bound to serum, alprenolol, pindolol and timolol to a lesser degree, and atenolol, metoprolol and sotalol were negligibly bound. For the five compounds which were appreciably bound, the mean binding was significantly higher in serum from patients with rheumatoid arthritis than in serum from normal volunteers. For those drugs, binding to ₁-acid glycoprotein was higher than to human serum albumin, and binding to a mixture of both proteins approached that to serum from healthy volunteers. For each of these drugs there was a strong correlation between the serum ₁-glycoprotein concentration and the percentage binding.     

Effects of dexamethasone and ibuprofen on LPS-induced gene expresion of TNF_ α,IL-1β,and MIP-1α in rat lung

研究地塞米松（Ｄｅｘ）和布洛芬（Ｉｂｕ）对脂多糖（ＬＰＳ）诱导的大鼠肺ＴＮＦα、ＩＬ-１β和ＭＩＰ-１α基因表达的影响．方法：荧光法测定肺中伊文斯蓝含量，Ｓｌｏｔｂｌｏｔ对细胞因子ｍＲＮＡ表达相对定量．结果：腹腔注射ＬＰＳ导致大鼠肺中ＴＮＦα、ＩＬ-１β和ＭＩＰ-１αｍＲＮＡ表达明显增加，与ＬＰＳ剂量有依赖关系，峰值分别在２，６，１２小时．在ＬＰＳ前１小时给药，Ｄｅｘ５０ｍｇ·ｋｇ－１和Ｉｂｕ９０ｍｇ·ｋｇ－１均明显降低肺中伊文斯蓝含量，同时ＴＮＦα、ＩＬ-１β和ＭＩＰ-１αｍＲＮＡ表达量亦明显减少．结论：ＬＰＳ诱导大鼠肺中ＴＮＦα、ＩＬ-１β和ＭＩＰ-１α基因表达，Ｄｅｘ和Ｉｂｕ通过抑制细胞因子表达而减轻肺损伤．     

Anti-mycobacterial, cytotoxic activities of Knoevenagel and (E)-α,β-unsaturated esters and ketones from 2-chloronicotinaldehydes

Series of 2-chloronicotinaldehyde Knoevenagel derivatives 3a–r; (E)-α,β-unsaturated esters and ketones 5a–k were prepared and evaluated for their in vitro anti-mycobacterial activity against Mycobacterium tuberculosis H₃₇Rv (Mtb). Compounds 3e, 5b, 5d, 5e, 5g and 5i–k were shown potent to significant activity. Compound 5j is the most potent Mtb inhibitor (MIC: 4.89 μM) when compared to standard drugs Ethambutol (MIC: 7.63 μM) and Ciprofloxacin (MIC: 9.44 μM). Eight compounds displayed potent/significant activity against M. tuberculosis were chosen for the cytotoxicity against three cell lines (Raw 264.7, MCF7, and HeLa). Compound 5j displayed low toxicity with high selective index (15–30) and is an interesting new compound may serve for the development of therapeutics targeted against anti-mycobacterial compounds. This is the first report assigning in vitro anti-mycobacterial inhibitory activity and structure–activity relationship for this class of substituted 2-chloronicotinaldehyde derivatives and presents new family of compounds.     

Pharmacokinetics and metabolism of TR-14035, a novel antagonist of α4β1/α4β7 integrin mediated cell adhesion,in rat and dog

The pharmacokinetics and disposition of N-(2,6-dichlorobenzoyl)-4-(2,6-dimethoxyphenyl)-L-phenylalanine (TR-14035), a novel α4β1/α4β7 antagonist, were investigated in the rat and dog. Results indicate extensive clearance of TR-14035 and low oral bioavailability, 17% and 13% in the rat and dog, respectively, at an oral dose of 10?mg/kg. At least 63% of the oral dose was absorbed from the gastrointestinal tract in the rat, and about one-third of the intravenous dose was excreted into bile as unchanged drug in the rat and dog. These data indicate that the oral bioavailability of TR-14035 was limited due to significant first-pass metabolism and biliary excretion in the liver. A species-dependent difference in metabolism was observed. The principal metabolite, O-desmethyl TR-14035, observed in rat, dog and probably human, was further conjugated with sulfate in the rat, but never in dog and human, based on in vitro metabolism and in vivo metabolite profile studies. Urinary excretion was a minor elimination route, but an interesting species difference was recognized. TR-14035 was reabsorbed from the rat renal proximal tubules, and by contrast, secreted into the tubules in the dog, probably via active transport systems.     

A fluorimetric,potentiometric and conductimetric study of the aqueous solutions of naproxen and its association with hydroxypropyl-β-cyclodextrin

The dissociation constant, K_a, of naproxen, a nonsteroidal antiinflammatory drug of the family of arylpropionic acids, has been determined in aqueous solutions at 25°C by using a potentiometric and a conductimetric techniques. The solubility limit of the drug in water, a controversial point in the literature, has been found to be less than 3×10⁻⁵ M. The interaction of naproxen with hydroxypropyl-β-cyclodextrin (HPBCD), in terms of the binding constants of the complexes formed by the CD and the nonionic (HNAP) and ionic (NAP⁻) species of the drug, has been evaluated at 25°C as well by means of steady-state fluorescence enhancement studies. A discussion of the results, K_HPBCD:HNAP=6500±400 M⁻¹ and K_HPBCD:NAP−=1400±80 M⁻¹, emphasizing the crucial importance of the choice of the pH at a value that pH≥pK_a +2 or pH≤pK_a −2, is also included.     

A novel delivery system of doxorubicin with high load and pH-responsive release from the nanoparticles of poly (α,β-aspartic acid) derivative

A poly (amino acid)-based amphiphilic copolymer was utilized to fabricate a better micellar drug delivery system (DDS) with improved compatibility and sustained release of doxorubicin (DOX). First, poly (ethylene glycol) monomethyl ether (mPEG) and DOX were conjugated onto polyasparihyazide (PAHy), prepared by hydrazinolysis of the poly (succinimide) (PSI), to afford an amphiphilic polymer [PEG-hyd-P (AHy-hyd-DOX)] with acid-liable hydrazone bonds. The DOX, chemically conjugated to the PAHy, was designed to supply hydrophobic segments. PEGs were also grafted to the polymer via hydrazone bonds to supply hydrophiphilic segments and prolong its lifetime in blood circulation. Free DOX molecules could be entrapped into the nanoparticles fabricated by such an amphiphilic polymer (PEG-hyd-P (AHy-hyd-DOX)), via hydrophobic interaction and π-π stacking between the conjugated and free DOX molecules to obtain a pH responsive drug delivery system with high DOX loaded. The drug loading capacity, drug release behavior, and morphology of the micelles were investigated. The biological activity of micelles was evaluated in vitro. The drug loading capacity was intensively augmented by adjusting the feed ratio, and the maximum loading capacity was as high as 38%. Besides, the DOX-loaded system exhibited pH-dependent drug release profiles in vitro. The cumulative release of DOX was much faster at pH 5.0 than that at pH 7.4. The DOX-loaded system kept highly antitumor activity for a long time, compared with free DOX. This easy-prepared DDS, with features of biocompatibility, biodegradability, high drug loading capacity and pH-responsiveness, was a promising controlled release delivery system for DOX.