["Component-target-efficacy" network analysis and experimental verification of Qingkailing Oral Preparation].

This study aims to explore the mechanism of Qingkailing(QKL) Oral Preparation's heat-clearing, detoxifying, mind-tranquilizing effects based on "component-target-efficacy" network. To be specific, the potential targets of the 23 major components in QKL Oral Preparation were predicted by the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform(TCMSP) and SwissTargetPrediction. The target genes were obtained based on UniProt. OmicsBean and STRING 10 were used for Gene Ontology(GO) term enrichment and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment of the targets. Cytoscape 3.8.2 was employed for visualization and construction of "component-target-pathway-pharmacological effect-efficacy" network, followed by molecular docking between the 23 main active components and 15 key targets. Finally, the lipopolysaccharide(LPS)-induced RAW264.7 cells were adopted to verify the anti-inflammatory effect of six monomer components in QKL Oral Preparation. It was found that the 23 compounds affected 33 key signaling pathways through 236 related targets, such as arachidonic acid metabolism, tumor necrosis factor α(TNF-α) signaling pathway, inflammatory mediator regulation of TRP channels, cAMP signaling pathway, cGMP-PKG signaling pathway, Th17 cell differentiation, interleukin-17(IL-17) signaling pathway, neuroactive ligand-receptor intera-ction, calcium signaling pathway, and GABAergic synapse. They were involved in the anti-inflammation, immune regulation, antipyretic effect, and anti-convulsion of the prescription. The "component-target-pathway-pharmacological effect-efficacy" network of QKL Oral Preparation was constructed. Molecular docking showed that the main active components had high binding affinity to the key targets. In vitro cell experiment indicated that the six components in the prescription(hyodeoxycholic acid, baicalin, chlorogenic acid, isochlorogenic acid C, epigoitrin, geniposide) can reduce the expression of nitric oxide(NO), TNF-α, and interleukin-6(IL-6) in cell supernatant(P<0.05). Thus, the above six components may be the key pharmacodynamic substances of QKL Oral Preparation. The major components in QKL Oral Prescription, including hyodeoxycholic acid, baicalin, chlorogenic acid, isochlorogenic acid C, epigoitrin, geniposide, cholic acid, isochlorogenic acid A, and γ-aminobutyric acid, may interfere with multiple biological processes related to inflammation, immune regulation, fever, and convulsion by acting on the key protein targets such as IL-6, TNF, prostaglandin-endoperoxide synthase 2(PTGS2), arachidonate 5-lipoxygenase(ALOX5), vascular cell adhesion molecule 1(VCAM1), nitric oxide synthase 2(NOS2), prostaglandin E2 receptor EP2 subtype(PTGER2), gamma-aminobutyric acid receptor subunit alpha(GABRA), gamma-aminobutyric acid type B receptor subunit 1(GABBR1), and 4-aminobutyrate aminotransferase(ABAT). This study reveals the effective components and mechanism of QKL Oral Prescription.

Isoeucommin A attenuates kidney injury in diabetic nephropathy through the Nrf2/HO-1 pathway.

Diabetic nephropathy (DN) is a common complication in patients with diabetes and a leading cause of mortality. The management of DN in the clinic still remains a challenge. Therefore, the identification of novel compounds for DN treatment and their characterization in preclinical DN models are crucial. Isoeucommin A is a lignan compound isolated from Eucommia ulmoides Oliv, which has not been studied in detail. Our aim was to investigate the effect of Isoeucommin A in DN and to elucidate the molecular mechanisms though which Isoeucommin A acts in vitro and in vivo. We first isolated and purified Isoeucommin A by microporous resin column chromatography and studied the mass spectrogram, as well as the structure of Isoeucommin A, by high-resolution electrospray ionization mass spectroscopy and NMR, respectively. We further established an in vivo rat DN model and measured the changes of blood glucose, body weight, kidney index (KI), blood urea nitrogen, creatinine (CRE), glutathione, malondialdehyde (MDA), SOD, albumin (ALB) and urinary ALB to CRE ratios on treatment with Isoeucommin A. In addition, we measured SOD, MDA, glycogen synthase kinase-3ß (GSK-3ß), phosphorylated (p)-GSK-3ß, nuclear factor erythroid-derived 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) levels by quantitative real-time PCR and western blot, and estimated cell viability by a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide assay. After Isoeucommin A treatment, body weight, as well as SOD, glutathione, HO-1 and Nrf2 expression levels, in DN rats increased in a dose-dependent manner. In contrast, the levels of blood glucose, KI, blood urea nitrogen, CRE, urinary ALB to CRE ratio, tumor necrosis factor-α, interleukin-1ß, interleukin-6 and MDA decreased significantly. In addition, Isoeucommin A protected H2 O2 -stimulated renal tubular epithelial cells from oxidative stress and activated the Nrf2/HO-1 signaling pathway in high-glucose-stimulated human renal mesangial cells. In conclusion, Isoeucommin A could alleviate inflammation and oxidative stress in in vitro and in vivo DN models and thus attenuate kidney injury by activating the Nrf2/HO-1 signaling pathway. Isoeucommin A could have the potential to be used as an effective drug for the treatment of DN.

Lignans and phenolic constituents from Eucommia ulmoides Oliver.

Two new lignans, noreucol A (1) and (+)-epicycloolivil (2), along with seven known compounds (3-9) were isolated from the aqueous extract of Eucommia ulmoides Oliver. Compound 1 was a new norlignan and 2 was an epimer at C-7 of (+)-cycloolivil (3). Their structures were elucidated by spectroscopic methods, and the absolute configurations of new compounds were determined by conformational analysis and DFT theoretic electronic circular dichroism spectra calculations. In addition, the neuroprotective activity of compounds 1-3 against glutamate-induced HT-22 cells injury were evaluated, and only compound 1 exhibited moderate effect at the concentrations ranging from 10 ∼ 50 µM.

LC-MS/MS determination of ginsenoside compound K and its metabolite 20 (S)-protopanaxadiol in human plasma and urine: applications in a clinical study.

AIM: Ginsenoside compound K (CK) is considered to be a potential therapeutic drug for rheumatoid arthritis because of its good anti-inflammatory activity. The purpose of this work was to establish a rapid, sensitive and specific method for determination of CK and its active metabolite 20(S)-protopanaxadiol (20(S)-PPD). Materials & methods: The analytes and internal standards were extracted by liquid-liquid extraction. Then, were separated by high performance liquid phase and determined by triple quadrupole mass spectrometry. RESULTS: A LC-MS/MS using liquid-liquid extraction was developed for determining CK over the concentration range 1.00-1002.00 ng/ml and 0.15-54.30 ng/ml for 20(S)-PPD. The lower limits of quantification for CK and 20(S)-PPD were 1.00 and 0.15 ng/ml, respectively. CONCLUSION: This method was successfully validated for detecting both CK and 20(S)-PPD in the human plasma and urine, and was proved to be suitable for the pharmacokinetic study of CK in healthy Chinese volunteers. CLINICAL TRIAL REGISTRATION NUMBER: ChiCTR-TRC-14004824.

Aucubin Alleviates Seizures Activity in Li-Pilocarpine-Induced Epileptic Mice: Involvement of Inhibition of Neuroinflammation and Regulation of Neurotransmission.

Neuroinflammation and imbalance of neurotransmitters play pivotal roles in seizures and epileptogenesis. Aucubin (AU) is an iridoid glycoside derived from Eucommia ulmoides that possesses anti-inflammatory and neuroprotective effects. However, the anti-seizure effects of AU have not been reported so far. The present study was designed to investigate the effects of AU on pilocarpine (PILO) induced seizures and its role in the regulation of neuroinflammation and neurotransmission. We found that AU reduced seizure intensity and prolonged the latency of seizures. AU significantly attenuated the activation of astrocytes and microglia and reduced the levels of interleukine-1 beta (IL-1ß), high mobility group box 1 (HMGB1), tumor necrosis factor-α (TNF-α). Furthermore, the contents of γ-aminobutyric acid (GABA) were increased while the levels of glutamate were decreased in the hippocampus with AU treatment. The expression of γ-aminobutyric acid type A receptor subunit α1 (GABAARα1) and glutamate transporter-1 (GLT-1) protein were up-regulated in AU treatment group. However, AU had no significant effect on N-methyl-d-aspartate receptor subunit 2B (NR2B) expression in status epilepticus (SE). In conclusion, our findings provide the first evidence that AU can exert anti-seizure effects by attenuating gliosis and regulating neurotransmission. The results suggest that AU may be developed as a drug candidate for the treatment of epilepsy.

Relationship between polymorphisms of the lipid metabolism-related gene PLA2G16 and risk of colorectal cancer in the Chinese population.

This study aimed to investigate the relationship between polymorphisms in the lipid metabolism-related gene PLA2G16 encoding Group XVI phospholipase A2 and the risk of colorectal cancer (CRC) in the Chinese population. A total of 185 patients with CRC and 313 healthy controls were enrolled. Thirteen single nucleotide polymorphisms (SNPs) of PLA2G16 were genotyped with SNPscan™. Linkage disequilibrium and haplotypes were analysed using Haploview software. Multivariate logistic regression was used to determine the association between the various genotypes and CRC risk. We identified five PLA2G16 SNPs (rs11600655, rs3809072, rs3809073, rs640908 and rs66475048) that were associated with CRC risk after adjusting for age, sex and body mass index. Two haplotypes (CTC and GGA) of rs11600655, rs3809073 and rs3809072, were relevant to CRC risk. The rs11600655 polymorphism was also associated with lymph node metastasis and CRC staging, while rs3809073 and rs3809072 may affect transcriptional regulation of PLA2G16 by altering transcription factor binding. These findings suggest that PLA2G16 polymorphisms-especially CTC and GGA haplotypes-increase CRC susceptibility. Importantly, we showed that the rs11600655 CC, rs640908 CT and rs66475048 GA genotypes are independent risk factors for CRC in the Chinese population.

The Effects of Ginsenoside Compound K Against Epilepsy by Enhancing the γ-Aminobutyric Acid Signaling Pathway.

The imbalance between the GABA-mediated inhibition and the glutamate-mediated excitation is the primary pathological mechanism of epilepsy. GABAergic and glutamatergic neurotransmission have become the most important targets for controlling epilepsy. Ginsenoside compound K (GCK) is a main metabolic production of the ginsenoside Rb1, Rb2, and Rc in the intestinal microbiota. Previous studies show that GCK promoted the release of GABA from the hippocampal neurons and enhanced the activity of GABAA receptors. GCK is shown to reduce the expression of NMDAR and to attenuate the function of the NMDA receptors in the brain. The anti-seizure effects of GCK have not been reported so far. Therefore, this study aimed to investigate the effects of GCK on epilepsy and its potential mechanism. The rat model of seizure or status epilepticus (SE) was established with either Pentylenetetrazole or Lithium chloride-pilocarpine. The Racine's scale was used to evaluate seizure activity. The levels of the amino acid neurotransmitters were detected in the pilocarpine-induced epileptic rats. The expression levels of GABAARα1, NMDAR1, KCC2, and NKCC1 protein in the hippocampus were determined via western blot or immunohistochemistry after SE. We found that GCK had deceased seizure intensity and prolonged the latency of seizures. GCK increased the contents of GABA, while the contents of glutamate remained unchanged. GCK enhanced the expression of GABAARα1 in the brain and exhibited a tendency to decrease the expression of NMDAR1 protein in the hippocampus. The expression of KCC2 protein was elevated by the treatment of GCK after SE, while the expression of NKCC1 protein was reversely down-regulated. These findings suggested that GCK exerted anti-epileptic effects by promoting the hippocampal GABA release and enhancing the GABAAR-mediated inhibitory synaptic transmission.

The potent mechanism-based inactivation of CYP2D6 and CYP3A4 with fusidic acid in in vivo bioaccumulation.

1. The accumulation of fusidic acid (FA) after multiple doses of FA has been reported on in previous studies but the related mechanisms have not been clarified fully. In the present study, we explain the mechanisms related to the mechanism-based inactivation of CYP2D6 and CYP3A4. 2. The irreversible inhibitory effects of FA on CYP2D6 and CYP3A4 were examined via a series of experiments, including: (a) time-, concentration- and NADPH-dependent inactivation, (b) substrate protection in enzyme inactivation and (c) partition ratio with recombinant human CYP enzymes. Metoprolol α-hydroxylation and midazolam 1'-hydroxylation were used as marker reactions for CYP2D6 and CYP3A4 activities, and HPLC-MS/MS measurement was also utilised. 3. FA caused to the time- and concentration-dependent inactivation of CYP2D6 and CYP3A4. About 55.8% of the activity of CYP2D6 and 75.8% of the activity of CYP3A4 were suppressed after incubation with 10 µM FA for 15 min. KI and kinact were found to be 2.87 µM and 0.033 min-1, respectively, for CYP2D6, while they were 1.95 µM and 0.029 min-1, respectively, for CYP3A4. Inhibition of CYP2D6 and CYP3A4 activity was found to require the presence of NADPH. Substrates of CYP2D6 and CYP3A4 showed that the enzymes were protected against the inactivation induced by FA. The estimated partition ratio for the inactivation was 7 for CYP2D6 and 12 for CYP3A4. 4. FA is a potent mechanism-based inhibitor of CYP2D6 and CYP3A4, which may explain the accumulation of FA in vivo.

Aucubin Alleviates Bleomycin-Induced Pulmonary Fibrosis in a Mouse Model.

Pulmonary fibrosis is a life-threatening disease characterized by progressive dyspnea and worsening of pulmonary function. No effective therapeutic strategy for pulmonary fibrosis has been established. Aucubin is a natural constituent with a monoterpene cyclic ring system. The potency of aucubin in protecting cellular components against inflammation, oxidative stress, and proliferation effects is well documented. In this study, we investigated the protective effect of aucubin against pulmonary fibrosis in mice. A mouse model of pulmonary fibrosis was established by intratracheal injection of bleomycin (BLM), and aucubin was administered for 21 days after BLM injection. We found that aucubin decreased the breathing frequency and increased the lung dynamic compliance of BLM-stimulated mice detected by Buxco pulmonary function testing system. Histological examination showed that aucubin alleviated BLM-induced lung parenchymal fibrotic changes. Aucubin also reduced the intrapulmonary collagen disposition and inflammatory injury induced by BLM. In addition, aucubin reduced the expression of pro-fibrotic protein transforming growth factor (TGF)-ß1 and α-smooth muscle actin (α-SMA) of pulmonary fibrosis mice induced by BLM. Furthermore, the effect of aucubin on the proliferation and differentiation of fibroblast was investigated in vitro. Aucubin inhibited the mRNA and protein expression of Ki67 and proliferating cell nuclear antigen (PCNA) induced by TGF-ß1 and reduced the cell proliferation in a murine fibroblast cell NIH3T3. Aucubin also reduced the collagen syntheses and α-SMA expression induced by TGF-ß1 in fibroblast. Our results indicate that aucubin inhibits inflammation, fibroblast proliferation, and differentiation, exerting protective effects against BLM-induced pulmonary fibrosis in a mouse model. This study provides an evidence that aucubin may be a novel drug for pulmonary fibrosis.

Two Single Nucleotide Polymorphisms (rs2431697 and rs2910164) of miR-146a Are Associated with Risk of Coronary Artery Disease.

The coronary artery disease (CAD) is one of the most severe cardiovascular diseases. MicroRNA-146a (miR-146a) influences the pathology of cardiovascular diseases. Two single nucleotide polymorphisms (SNPs) of miR-146a (rs2431697 and rs2910164) have been reported to alter the function or expression of microRNA. The purpose of this study is to evaluate the association between miR-146a gene polymorphism and the risk of CAD in the Chinese population. A total of 353 CAD patients and 368 controls were recruited, and SNPs were analyzed by the matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and Sequenom MassARRAY system. The gene frequencies of rs2431697 and rs2910164 were significantly different between the two groups. The mutant type (T allele) of rs2431697 and wild type (C allele) of rs2910164 were more frequent in CAD patients. T allele carriers in rs2431697 had an increased CAD risk, while G allele of rs2910164 decreased the risk of CAD significantly. In conclusion, we found that the T allele of rs2431697 was a risk factor of CAD in the Chinese population. Meanwhile, we demonstrated that the G allele of rs2910164 decreased the susceptibility of CAD.

The Protective Effect of Aucubin from Eucommia ulmoides Against Status Epilepticus by Inducing Autophagy and Inhibiting Necroptosis.

Eucommia ulmoides Oliv. is a famous traditional Chinese medicine which exhibits anti-oxidative stress ability and neuro-protective effects. Aucubin is the predominant component of Eucommia ulmoides Oliv. Our present study is intended to investigate aucubin's potential protective effects on neurons against epilepsy in the hippocampus by establishing the lithium-pilocarpine induced status epilepticus (SE) rat model in vivo. Aucubin (at a low dose and a high dose of 5[Formula: see text]mg/kg and 10[Formula: see text]mg/kg, respectively) was administered through gavage for two weeks before lithium-pilocarpine injection. Rats were sacrificed at 4, 24 and 72[Formula: see text]h after SE induction. Pretreatment with both low-dose and high-dose aucubin significantly reduced the number of death neurons ([Formula: see text]) and increased the number of surviving neurons ([Formula: see text]) in DG, Hilus, CA1 and CA3 hippocampal regions post SE. Meanwhile, it significantly inhibited necroptosis proteins (MLKL and RIP-1) ([Formula: see text] or [Formula: see text]) and enhanced autophagy protein (Beclin-1 and LC3BII/LC3BI) prevalence in the hippocampus ([Formula: see text] or [Formula: see text]). In conclusion, aucubin appeared to ameliorate damages in lithium-pilocarpine induced SE in hippocampus, reduce the number of apoptotic neurons, and increased the number of survival neurons by inducing autophagy and inhibiting necroptosis. These original findings might provide an important basis for the further investigation of the therapeutic role of aucubin in treatment or prevention of epilepsy-related neuronal damages.

Effects of FMO3 Polymorphisms on Pharmacokinetics of Sulindac in Chinese Healthy Male Volunteers.

Sulindac is a nonsteroidal anti-inflammatory drug, which is clinically used for the ailments of various inflammations. This study investigated the allele frequencies of FMO3 E158K and E308G and evaluated the influences of these two genetic polymorphisms on the pharmacokinetics of sulindac and its metabolites in Chinese healthy male volunteers. Eight FMO3 wild-type (FMO3 HHDD) subjects and seven FMO3 homozygotes E158K and E308G mutant (FMO3 hhdd) subjects were recruited from 247 healthy male volunteers genotyped by PCR-RFLP method. The plasma concentrations of sulindac, sulindac sulfide, and sulindac sulfone were determined by UPLC, while the pharmacokinetic parameters of the two different FMO3 genotypes were compared with each other. The frequencies of FMO3 E158K and E308G were 20.3% and 20.1%, respectively, which were in line with Hardy-Weinberg equilibrium (D' = 0.977, r2 = 0.944). The mean values of Cmax, AUC0-24, and AUC0-∞ of sulindac were significantly higher in FMO3 hhdd group than those of FMO3 HHDD group (P < 0.05), while the pharmacokinetic parameters except Tmax of sulindac sulfide and sulindac sulfone showed no statistical difference between the two groups. The two FMO3 mutants were in close linkage disequilibrium and might play an important role in the pharmacokinetics of sulindac in Chinese healthy male volunteers.

Aucubin and its hydrolytic derivative attenuate activation of hepatic stellate cells via modulation of TGF-ß stimulation.

Eucommia ulmoides is an important traditional Chinese medicine and has been used as a tonic with a long history. Aucubin is an active component extracted from Eucommia ulmoides, which has liver-protection effects. However the mechanisms are still unclear. To investigate the inhibitory effects and the underlying mechanisms of aucubin on TGF-ß1-induced activation of hepatic stellate cells and ECM deposition, Human hepatic stellate cells (LX-2 cells) were incubated with TGF-ß1 to evaluate the anti-fibrotic effect of aucubin. Western blot was used to investigate the expression of α-SMA, Col I, Col III, MMP-2 and TIMP-1. ROS production was monitored using DCFH-DA probe, and NOX4 expression was detected by Real-time PCR. Results indicated that TGF-ß1 stimulated the activation and ECM deposition of LX-2 cells. Compared with the control group, aucubin and aucubigenin both reduced the protein expression of α-SMA, Col I, Col III and MMP-2 in LX-2 cells. Aucubin and aucubigenin also suppressed the generation of ROS and down-regulated the NOX4 mRNA expression. Taken together, aucubin and aucubigenin both inhibit the activation and ECM deposition of LX-2 cells activated by TGF-ß1. Aucubin and aucubigenin are potential therapeutic candidate drugs for liver fibrosis.

The effect of SLCO1B1 polymorphism on the pharmacokinetics of atorvastatin and 2-hydroxyatorvastatin in healthy Chinese people.

The pharmacokinetics of statins show substantial inter-subject variability. Increasing systemic exposure of statins may lead to adverse drug reactions such as myopathy. The variation in statin pharmacokinetics is partly explained by genetic factors. OATP1B1, coded by SLCO1B1 transports a large number of therapeutic drugs, such as atorvastatin. Here we investigated the effect of SLCO1B1 polymorphism on the pharmacokinetics of atorvastatin and its metabolites. Two pharmacokinetic studies were conducted in Chinese Han volunteers and 132 volunteers were enrolled in our study as 72 in trial 1 and 60 in trial 2. A LC-MS/MS method was developed for the identification and quantification of atorvastatin acid and its metabolites. S LCO1B1 c.521T>C (rs4149056) was identified by the MALDI-TOF MS and Sequenom MassARRAY system. The distribution frequencies of SLCO1B1 c.521T>C were in agreement with Hardy-Weinberg equilibrium both in trial 1 and trial 2. In subjects with 521C allele the mean Cmax, AUC0-24h and AUC0-∞ of atorvastatin acid and 2-hydroxyatorvastatin acid were significantly higher than subjects with 521TT genotype, while the mean CL was lower. In conclusion, our results suggested that SLCO1B1 c.521T>C had an effect on the pharmacokinetics of atorvastatin and 2-hydroxyatorvastatin in Chinese Han population. Subjects with 521C allele have an increased risk of toxic effects caused by atorvastatin.

Aldose reductase C-106T polymorphism is associated with the risk of essential hypertension.

Aldose Reductase (AR), encoded by AKR1B1, is a member of NADPH-dependent aldo-keto reductase superfamily. The C-106T polymorphism of AKR1B1 is closely related to the diabetic complications. Our previous studies have indicated that the expression of AR was increased in spontaneously hypertensive rats, suggesting the effect of AR in hypertension. Here we investigated whether AKR1B1 C-106T polymorphism was associated with essential hypertension (EH). AKR1B1 C-106T polymorphism was genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and the direct sequencing methods. 383 healthy subjects and 383 essential hypertensive patients were recruited in this study. The polymorphism of AKR1B1 C-106T in EH and normal tensive (NT) groups was in agreement with Hardy-Weinberg equilibrium. -106T allele of AKR1B1 C-106T variants was more frequent in EH patients compared with normal tensive subjects, indicating that -106T allele was a risk factor of EH (OR=1.841, 95%CI=1.366-2.481). In male patients, C-106T polymorphism was associated significantly with decreased serum high density lipoprotein cholesterol and higher systolic blood pressure levels. Our results suggest that -106T allele of AKR1B1 C-106T polymorphism may be associated with increased risk for EH in Chinese Han population.

Kinetics of cytochrome P450 enzymes for metabolism of sodium tanshinone IIA sulfonate in vitro.

BACKGROUND: Sodium tanshinone IIA sulfonate (STS) is a water-soluble derivative of tanshinone IIA for treating cardiovascular disorders. The roles of cytochrome P450 enzymes (CYPs) in the metabolism of STS have remained unclear. This study aims to screen the main CYPs for metabolism of STS and study their interactions in vitro. METHODS: Seven major CYPs were screened for metabolism of STS by human liver microsomes (HLMs) or recombinant CYP isoforms. Phenacetin (CYP1A2), coumarin (CYP2A6), tolbutamide (CYP2C9), metoprolol (CYP2D6), chlorzoxazone (CYP2E1), S-mephenytoin (CYP2C19), and midazolam (CYP3A4) were used as probe substrates to determine the potential of STS in affecting CYP-mediated phase I metabolism in humans. Enzyme kinetic studies were performed to investigate the modes of inhibition of the enzyme-substrate interactions by GraphPad Prism Enzyme Kinetic 5 Demo software. RESULTS: Sodium tanshinone IIA sulfonate inhibited the activity of CYP3A4 in a dose-dependent manner by the HLMs and CYP3A4 isoform. The K m and V max values of STS were 54.8 ± 14.6 µM and 0.9 ± 0.1 nmol/mg protein/min, respectively, for the HLMs and 7.5 ± 1.4 µM and 6.8 ± 0.3 nmol/nmol P450/min, respectively, for CYP3A4. CYP1A2, CYP2A6, CYP2C9, CYP2D6, CYP2E1, and CYP2C19 showed minimal or no effects on the metabolism of STS. CONCLUSION: This in vitro study showed that STS mainly inhibited the activities of CYP3A4.

Screening of Drug Metabolizing Enzymes for the Ginsenoside Compound K In Vitro: An Efficient Anti-Cancer Substance Originating from Panax Ginseng.

Ginsenoside compound K (CK), a rare ginsenoside originating from Panax Ginseng, has been found to possess unique pharmacological activities specifically as anti-cancers. However, the role of cytochrome P450s (CYPs) in the metabolism of CK is unclear. In this study, we screened the CYPs for the metabolism of CK in vitro using human liver microsomes (HLMs) or human recombinant CYPs. The results showed that CK inhibited the enzyme activities of CYP2C9 and CYP3A4 in the HLMs. The Km and Vmax values of CK were 84.20±21.92 µM and 0.28±0.04 nmol/mg protein/min, respectively, for the HLMs; 34.63±10.48 µM and 0.45±0.05 nmol/nmol P450/min, respectively, for CYP2C9; and 27.03±5.04 µM and 0.68±0.04 nmol/nmol P450/min, respectively, for CYP3A4. The IC50 values were 16.00 µM and 9.83 µM, and Ki values were 14.92 µM and 11.42µM for CYP2C9 and CYP3A4, respectively. Other human CYP isoforms, including CYP1A2, CYP2A6, CYP2D6, CYP2E1, and CYP2C19, showed minimal or no effect on CK metabolism. The results suggested that CK was a substrate and also inhibitors for both CYP2C9 and CYP3A4. Patients using CK in combination with therapeutic drugs that are substrates of CYP2C9 and CYP3A4 for different reasons should be careful, although the inhibiting potency of CK is much poorer than that of enzyme-specific inhibitors.

A rapid, simple and sensitive method for the determination and bioequivalence study of transdermal fentanyl in human plasma using liquid chromatography-electrospray ionization tandem mass spectrometry.

OBJECTIVE: Since the 1960s, fentanyl has been used to replace morphine nd other opioids due to its higher potency in the treatment of acute pain; since the 1990s, it has also been administrated to control chronic pain by using transdermal fentanyl device system. It is crucial and of utmost importance and crucial to validate a sensitive method for the quantification of transdermal fentanyl in human plasma. MATERIALS AND METHODS: A rapid, simple and sensitive high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) method has been established and validated for the determination of transdermal fentanyl in human plasma using fentanyl-D5 as an internal standard (IS). Following liquid-liquid extraction (LLE) with n-hexane, the extracts were separated on a Thermo Hypersil ODS(C18) column (2.1 × 150 mm i.d., 5 µm) interfaced with a triple-quadrupole tandem mass spectrometer using positive electrospray ionization. RESULTS AND CONCLUSIONS: Quantification of fentanyl was carried out by multiple reaction monitoring (MRM) of the transitions at m/z 337.1→188.0 for fentanyl and 341.9→187.9 for IS. The lower limit of quantification was 9.75 pg×mL-1, and the test showed a linear range of 9.75 - 10,000 pg×mL-1. The validated method was subsequently applied to a bioequivalence (BE) study in 24 healthy Chinese volunteers by using transdermal fentanyl patches.

Eucommia ulmoides Oliv. (Du-Zhong) Lignans Inhibit Angiotensin II-Stimulated Proliferation by Affecting P21, P27, and Bax Expression in Rat Mesangial Cells.

Cortex Eucommiae (Du-zhong) is the dried bark of the Eucommia ulmoides Oliv. The natural products identified from Du-zhong include lignans, iridoids, flavonoids, polysaccharides, terpenes, and proteins, Liu et al. (2012). Lignans, the main bioactive components, were protective against hypertensive renal injury in spontaneous hypertensive rats in our previous study, Li et al. (2012). Moreover, Eucommia lignans also diminished aldose reductase (AR) overexpression in the kidney, Li et al. (2012). However, the pathological mechanism underlying the protective effects of Eucommia lignans remains unknown. Cellular proliferation was reported to contribute to important pathological changes in hypertensive renal injuries, and increased angiotensin II (Ang II) expression was reported to be essential for target-organ damage during hypertension. Ang II is the main effective peptide in the renin-angiotensin system and is considered to be a key mediator in the development of hypertensive nephropathy, Rüster and Wolf (2011). Our preliminary results showed that Eucommia lignans had inhibitory effects on Ang II-induced proliferation of rat mesangial cells. In the present study, we investigated the effects of Eucommia ulmoides on Ang II-induced proliferation and apoptosis of rat mesangial cells. Cell cycle-related genes P21 and P27, and cell apoptosis-related genes Bax and Bcl-2, were determined.