The protective effect of schisandrol A against senecionine-induced hepatotoxicity in mice / 药学学报

Hepatotoxicity induced by herbal medicines such as Gynura japonica, which contains large amount of pyrrolizidine alkaloids (PAs) such as senecionine (SEN), is among the most serious problems of herbal drug-induced liver injury, yet there is no effective treatment in clinic. We have previously reported that ritonavir (the well-known CYP3A4 inhibitor) protected rats against Gynura japonica-induced liver injury in rats, which was closely related to the inhibition of the metabolic activation of PAs. A large number of lignans have been identified in Schisandrae Chinensis Fructis and are reported to attenuate drug-induced liver injuries by modulating the drug metabolism enzymes. Therefore, the present study investigated the protective effect and potential mechanism of schisandrol A (SoA, a representative lignan identified in Schisandrae Chinensis Fructis) against SEN-induced hepatotoxicity in mice. All experiments were approved by the Animal Research Committee of Shanghai University of Traditional Chinese Medicine (PZSHUTCM210604002). Animal welfare and the animal experimental protocols were strictly consistent with related ethics regulations of Shanghai University of Traditional Chinese Medicine. Liver injury was induced by a single gavage of SEN (150 μmol·kg-1); mice in the protection group were gavaged with SoA (116 μmol·kg-1) 7 days before SEN treatment. The results show that SoA dramatically alleviated SEN-induced liver injury in mice. Mice in the protection group showed decreased serum activities for alanine aminotransferase and aspartate aminotransferase; in addition, the hepatic necrosis and sinusoidal hemorrhage in SEN-treated mice were markedly attenuated in the protection group. The serum contents of SEN metabolites in mice were decreased. In vitro studies were performed by using human liver microsomes and proved that SoA inhibits CYP3A4 to decrease the metabolism of SEN. These studies indicate that SoA attenuated SEN-induced liver injury in mice, which was closely related to the inhibition of the metabolic activation of SEN. These results provide a better understanding of the relationship between CYP3A4 and PA-induced toxicity. This work also will be helpful in developing effective treatments for SEN-induced liver injury based on inhibition of its metabolic activation, and in making reasonable evaluations of the safety of herbal medicines containing PAs such as G. japonica.

Lipid analysis of coronary atherosclerotic plaques and the mechanism of restenosis after coronary endarterectomy / 中华胸心血管外科杂志

Objective:To analyze the lipid composition of coronary atherosclerotic plaques and explore the mechanism of its influence on the medium and long-term efficacy of coronary endarterectomy(CE).Methods:From January 2018 to December 2019, a total of 50 patients with diffuse coronary artery disease(DCAD)and hyperlipidemia in Beijing Anzhen Hospital were enrolled to undergo coronary artery bypass grafting combined with anterior descending CE. After the informed consent was signed before the operation, the coronary endarterectomy plaque tissue and blood plasma samples were taken during the operation. Patients were further examined by coronary atherosclerosis T1-weighted characterization(CATCH) and power domain non-orthogonal multiple access(NOMA)postoperatively to analyze middle and long-term coronary restenosis risks. They were divided into high-risk group(restenosis rate >25%, study group) and matched low-risk group(control group). Lipid and molecular biological analysis were performed in the two groups to detect the tissue and cytochrome P450 3A4 enzyme(CYP3A4) content of plaque samples.Results:8 patients were enrolled in each group. The lipid analysis showed that and tissue samples from patients in the study group had a significantly higher level of 4α- Hydroxycholesterol(4α-OHC)as compared to the control group(0.050 μmol/g vs. 0.016 μmol/g, P<0.05). Further, 12 months after the operation, CATCH results showed that the patency rate of the control group was better than that of the study group[coronary artery stenosis rate(9.01±1.9)% vs.(22. 31±2.3)%, P<0.05]. Comparison of CYP3A4 content showed that: the CYP3A4 in blood plasma for the study group was higher than that in the control group[immediate(0.88±0.05)ng/ml vs.(0. 45±0.03) ng/ml and(2. 08± 0.40) ng/ml vs.(1. 58± 0.16)ng/ml, P<0.05]. Conclusion:High expression of 4 α- OHC may accelerate atherosclerosis(AS) after CE and cause restenosis in the middle and long term; It was also confirmed that 4 α- OHC is a biomarker of CYP3A4, which suggests for further investigation of the mechanism of progression after CE.

Activating Effect of Effective Components in Medicinal and Edible Substances on Human Pregnane X Receptor and Cytotoxicity Screening / 中国实验方剂学杂志

ObjectiveTo explore the activating effects of ten important effective components in seven medicinal and edible substances on human pregnane X receptor （PXR）， including Glycyrrhizae Radix et Rhizoma （liquiritin and glycyrrhizic acid）， Houttuyniae Herba （quercetin and houttuyfonate）， Prunellae Spica （rosmarinic acid）， Cassiae Semen （aurantio-obtusin）， Poria （pachymic acid）， Lilii Bulbus （Lilium brownii saponin and colchicine）， and Lycii Fructus （Lycium barbarum polysaccharide） and screen potentially toxic components. MethodCell counting kit-8 （CCK-8） assay was used to investigate the cytotoxic effect of liquiritin， glycyrrhizic acid， quercetin， houttuyfonate， rosmarinic acid， pachymic acid， aurantio-obtusin， and colchicine （10， 20， and 50 μmol·L-1）， and L. brownii saponin and L. barbarum polysaccharide （10， 20， and 50 mg·L-1） on normal human hepatocyte cell line （L02）. The release of lactate dehydrogenase （LDH） in L02 cells after drug treatments was detected by the biochemical analyzer. The apoptosis induced by ten effective components was explored by Hoechst 33342 staining. The secreted luciferase reporter system was used to co-transfect the PXR expression vector and reporter gene vector containing cytochrome P450 3A4 （CYP3A4） transcriptional regulatory region into L02 cells， with 10 μmol·L-1 rifampicin （RIF） as a positive control. After treated with liquiritin， glycyrrhizic acid， quercetin， houttuyfonate， rosmarinic acid， aurantio-obtusin， pachymic acid， and colchicine （5， 10， and 20 μmol·L-1） and L. brownii saponin and L. barbarum polysaccharide （5， 10， and 20 mg·L-1） for 24 h， the cells were tested for secreted luciferase activity. ResultCompared with the control group， colchicine， L. brownii saponin， and quercetin decreased the cell viability （P<0.05， P<0.01）. Compared with the control group， quercetin， rosmarinic acid， glycyrrhizic acid， colchicine， aurantio-obtusin， and pachymic acid increased the release rate of LDH in L02 cells （P<0.05， P<0.01）. The proportion of hyperchromatic nuclei increased gradually after rosmarinic acid， liquiritin， and L. barbarum polysaccharide treatments as compared with the control group （P<0.05， P<0.01）. In terms of co-transfection of pcDNA3.1-PXR and pGLuc-CYP3A4 into L02 cells， compared with the control group， aurantio-obtusin and pachymic acid showed activating effects on PXR （P<0.05）， whereas liquiritin and glycyrrhizic acid showed inhibitory effects （P<0.05）. ConclusionThe findings suggest that when medicinal and edible substances are taken for a long time， attention should be paid to their influence on drug-metabolizing enzymes and possible interactions， so as to improve their safety.

Mechanistic understanding of the inhibitory effect of cytochrome P450 3A4 and 3A5 by Wuzhi tablet (Schisandra sphenanthera extract) / 药学学报

Wuzhi tablet (WZ) is a prescribed herbal medicine extracted from Schisandra sphenanthera, which is widely used to protect the liver injury and drug-induced hepatotoxicity in clinical practices. Previous studies showed that WZ significantly increased the blood concentrations of tacrolimus, cyclosporine A, paclitaxel by inhibiting the cytochrome P450 3A (CYP3A)-mediated metabolism. CYP3A4 and CYP3A5 are the most important isoenzymes among the CYP3A subfamily. However, there are some differences in the catalytic and inhibitory activities between CYP3A4 and CYP3A5, which may lead to different risk of drug-drug and herb-drug interactions, and the risks may be further amplified in vivo. Currently, few reports have compared the herbal medicine inhibitory effects between CYP3A4 and CYP3A5 mediated metabolic reactions. Therefore, detailing the inhibitory effect of WZ on CYP3A4 and CYP3A5 will help understand and predict the potential herb-drug interaction. The results showed that WZ inhibited CYP3A4 and CYP3A5 in a NADPH-, time- and concentration- dependent manner. WZ showed more potent inhibition on CYP3A5 than CYP3A4. Cautions warranted when combining WZ with other therapeutic drugs to avoid the potential herb-drug interaction.

The protective effect of ritonavir against Gynura japonica-induced liver injury in rats / 药学学报

Numerous in vitro studies have shown that most pyrrolizidine alkaloids (PAs) are hepatotoxic after being metabolically activated by cytochrome P450 (CYP) 3A4. However, the key role of CYP3A4 has not been confirmed in vivo. Therefore, the CYP3A4 chemical inhibitor ritonavir was employed in this work and the effect of ritonavir on Gynura japonica-induced liver injury in rats was investigated. All experiments were approved by the Animal Research Committee of Shanghai University of Traditional Chinese Medicine. Animal welfare and the animal experimental protocols were strictly consistent with related ethics regulations of Shanghai University of Traditional Chinese Medicine. Acute liver injury was induced by a single gavage of Gynura japonica extracts (GJE, 8 g·kg-1); rats in the protection group were gavaged with ritonavir (RIT, 30 mg·kg-1) 1 h before GJE treatment. The results show that RIT could significantly attenuate GJE-induced liver injury in rats. Rats in the protection group showed decreased serum activities for alanine aminotransferase and aspartate aminotransferase, as well as lower total bile acids. In addition, the infiltration of inflammatory cells, sinusoidal hemorrhage, and hepatic necrosis in GJE-treated rats were markedly attenuated in the protection group. The content of pyrrole-protein adducts (PPAs), a recommended biomarker for PA-induced hepatotoxicity in clinics, was determined at 10 min to 24 h after GJE treatment. The content of 13 bile acids was also quantified. RIT treatment reduced the content of PPAs in serum dramatically and restored the impaired bile acid homeostasis caused by GJE. These studies indicate that RIT attenuated Gynura japonica-induced liver injury in rats, which was closely related to the inhibition of the metabolic activation of PAs and the regulation of bile acid metabolism. These results provide a better understanding of the relationship between CYP3A4 and PA-induced toxicity. This work will also be helpful in developing effective treatments for PA-induced liver injury and making a reasonable evaluation of the safety of drugs containing PAs in clinic.

Pharmacokinetic drug–drug interaction study between clindamycin and cyclosporin in rabbits

Cyclosporine A (CSA) is an immunosuppressant drug, metabolized mainly by CYP3A4 that is one of the CytochromeP450 enzymes. Clindamycin (CLN) is a lincosamide antibiotic, inducing CYP3A4 activity in vitro, and thereby mayalter CSA pharmacokinetics (PK). The current research was performed to investigate the PK parameters changes ofCSA up on co-administrating with CLN in healthy male rabbits. Twelve healthy male rabbits randomly were selectedand divided into two groups: Control set (n = 6) in which the rabbits were received oral normal saline CSA solution(10 mg/kg/day), meanwhile rabbits in the test group (n = 6) were treated with oral normal saline CSA solution (10 mg/kg/day) concomitantly with normal saline solution of CLN (8 mg/kg/day) at the same time for 7 days. Blood samples(2 ml) were collected and CSA concentrations were measured in whole blood at the predetermined time points byusing Chemiluminescent Immunoassay (CLIA) detection kit. PK profiles of CSA for both groups in the control andtest groups including Cmax, tmax, AUC0-24, the area under the blood concentration–time curve from 0 hour to infinity(AUC0-∞), t½, and Ke were compared. The results showed a statistically insignificant differences in the PK parametersof CSA alone or combined with CLN with p > 0.05. In conclusion, it has been found that CLN does not affect the CSAPK. Further confirmation of our findings is requiered in humans before these results can be applied in patient care.

UHPLC-MS-MS high throughput analysis-based screening and evaluation of PXR/CYP3A4-induced lipid-regulating quality marker in propolis / 中草药

Objective: To screen and evaluate PXR/CYP3A4-induced lipid-regulating quality marker in propolis with precise and quantitative method. Methods: The LS174T cell was given certain amount of midazolam injection, along with different dosage of known components found in propolis, after incubation and extraction, the samples were determined for 1’-OH-midazolam, and each compound was evaluated to discover the PXR/CYP3A4 pathway regulatory activity according to the results; Then, compounds selected were used as indexes for UHPLC-MS-MS content determination, and their own values were regarded as a preliminary step of confirming PXR/CYP3A4-induced lipid-regulating quality markers of propolis. Results: In all components tested, chrysin, galangin, heterochlorogenic acid A, quercetin, and caffeic acid phenethylester significantly affected the 1’-OH-midazolam yield compared with blank and positive control, indicating their obvious influence on PXR/CYP3A4 expression; The UHPLC-MS-MS determination showed that except galangin, heterochlorogenic acid A, and quercetin, all the other compounds had adequate content in propolis to take effect. Conclusion: Chrysin, galangin, caffeic acid phenethylester, and quercetin were probably defined as PXR/CYP3A4-induced lipid-regulating quality marker in propolis, which inhibited the expression of such targets to down-regulate blood lipid level; Additionally, the method used for quality marker screening and evaluation in this study was fast, effective and quantitative, and capable of carrying out high throughput active component screening for PXR/CYP3A4 regulatory activities.

Detoxification mechanism of Aconiti Lateralis Radix Praeparata combined with dried Rehmanniae Radix based on metabolic enzymes in liver / 中国中药杂志

The enzymes CYP1 A2 and CYP3 A4 were measured by building a "Cocktail" probe drug and the incubation system of liver microsomes. The compatibility of Aconiti Lateralis Radix Praeparata combined with dried Rehmanniae Radix on CYP450 enzyme protein and gene expression was explored from the level of protein and molecular biology. It explored the molecular mechanism of compatibility detoxication of Aconiti Lateralis Radix Praeparata to provide scientific support for clinical safe and effective application of Aconiti Lateralis Radix Praeparata. The CYP450 enzyme activity was determined by using "Cocktail" probe drugs. The content of CYP450 enzyme was measured by CO reduction of differential spectrum method. The mRNA expression of CYP1 A2 and CYP3 A4 enzyme was detected by RT-PCR technology. Compared with the blank group, the CYP1 A2 and CYP3 A4 enzyme activity and mRNA expression were increased in the dried Rehmanniae Radix combined with Aconiti Lateralis Radix Praeparata group with significant differences(P<0.05), while the CYP3 A4 enzyme activity and mRNA expression were no influence in the Aconiti Lateralis Radix Praeparata group. The CYP3 A4 enzyme activity and mRNA expression were increased in the dried Rehmanniae Radix and the dried Rehmanniae Radix combined with Aconiti Lateralis Radix Praeparata group, and there were significant differences(P<0.05). The content of CYP450 enzyme was decreased in the Aconiti Lateralis Radix Praeparata group, contributed to extremely significant difference(P<0.01). The content of CYP450 enzyme was increased in the dried Rehmanniae Radix and the dried Rehmanniae Radix combined with Aconiti Lateralis Radix Praeparata group, and there were significant differences(P<0.05). The CYP1 A2 and CYP3 A4 enzyme activity and gene expression were enhanced after dried Rehmanniae Radix combined with Aconiti Lateralis Radix Praeparata. The metabolism of toxic ingredients of Aconiti Lateralis Radix Praeparata was accelerated to reach an effect of detoxication. The detoxication mechanism of compatibility of Aconiti Lateralis Radix Praeparata was verified from the viewpoint of liver metabolic enzymes.

The 3'-untranslated region contributes to the pregnane X receptor (PXR) expression down-regulation by PXR ligands and up-regulation by glucocorticoids

Pregnane X receptor (PXR) is the major regulator of xenobiotic metabolism. PXR itself is controlled by various signaling molecules including glucocorticoids. Moreover, negative feed-back regulation has been proposed at the transcriptional level. We examined the involvement of the 3'-untranslated region (3'-UTR) of mRNA and microRNAs in PXR- and glucocorticoid receptor (GR)-mediated regulation of gene expression. PXR ligands were found to significantly downregulate mRNA expression in a set of 14 human hepatocyte cultures. Similarly, PXR was downregulated by PCN in the C57/BL6 mice liver. In mechanistic studies with the full-length 3'-UTR cloned into luciferase reporter or expression vectors, we showed that the 3'-UTR reduces PXR expression. From the miRNAs tested, miR-18a-5p inhibited both expression and gene induction. Importantly, we observed significant upregulation of miR-18a-5p expression 6 h after treatment with the PXR ligand rifampicin, which indicates a putative mechanism underlying negative feed-back regulation in hepatic cells. Additionally, glucocorticoids upregulated expression not only through the promoter region but also 3'-UTR regulation, which likely involves downregulation of miR-18a-5p. We conclude that miR-18a-5p is involved in the down-regulation of expression by its ligands and in the upregulation of mRNA expression by glucocorticoids in hepatic cells.

CYP3A4*18 and CYP3A5*3 Polymorphisms in Modulating Susceptibility Risk in Malaysian Chronic Myeloid Leukaemia Patients

@#CYP3A4 and CYP3A5 are metabolizing enzymes abundantly expressed in liver and involved in the metabolism of xenobiotics as well as clinically used drugs. Genetic polymorphisms in CYP3A4 and CYP3A5 may alter the metabolic ability of individuals. Thus, CYP3A4 and CYP3A5 might play an important role in the aetiology of chronic myeloid leukaemia (CML) and as modulators of cancer therapy response. In this study, the impact of two single nucleotide polymorphisms (SNPs) CYP3A4*18 (878T>C) and CYP3A5*3 (6986A>G) on CML susceptibility risk was investigated. This case-control study involved a total of 520 study subjects comprising 270 CML patients and 250 normal healthy controls. Genotyping of CYP3A4*18 and CYP3A5*3 was performed by polymerase chain reaction – restriction fragment length polymorphism (PCR-RFLP) technique. The association between allelic variants and CML susceptibility risk was assessed by logistic regression analysis, deriving odds ratio (OR) with 95% confident intervals. The results showed that heterozygous (*1/*1*8) genotype of CYP3A4*18 was significantly associated with CML susceptibility risk (OR 3.387; 95% CI: 1.433–8.007, p = 0.005). No homozygous variant (*18/*18) genotype was detected in this study. On the contrary, homozygous variant (*3/*3) and heterozygous (*1/*3) genotypes of CYP3A5*3 were associated with significantly lower risk for CML susceptibility (OR 0.140; 95% CI: 0.079–0.246’ p < 0.001 and OR 0.310; 95% CI: 0.180–0.535, p < 0.001, respectively). The results prompt us to conclude that genetic variation in CYP3A4*18 may contribute to a higher risk whereas CYP3A5*3 polymorphism confers a lower susceptibility risk in Malaysian CML patients.

Study on correlation between plasma concentration of cyclosporine injection and gene polymorphism in renal transplant patients / 药学实践杂志

Objective To investigate the clinical efficacy of cyclosporine injection in subclinical or critical treatment of renal transplant patients，and to establish an individualized dosage regimen of cyclosporine injection by studying the effects of nine single nucleotide polymorphisms related to the pharmacokinetics of cyclosporine on the dose-adjusted trough concentration (C0/D′) of cyclosporine injection. Methods Blood samples and clinical data of 144 adult renal transplant patients who used cyclosporine injection were collected and recorded, then, their genotypes of CYP3A4*18B, CYP3A5*3, ABCB1 (C1236T, G2677T/A, C3435T), POR*28, PXR (C5705T, C39823T) and NFKB1-94 ins/del ATTG were determined by Sequenom MassARRAY® SNP methods. Then, the discrepancies of cyclosporine injection’s C0/D′ among the patients with different genotypes was compared and an individualized dosage regimen based on gene polymorphism of cyclosporine injection was established by using multivariate regression analysis. Results Cyclosporine injection improved serum creatinine level by 68.8% in renal transplant patients with subclinical or critical rejection, and the steady-state plasma concentration was (189.50±38.56) ng/ml. The CYP3A4*18B gene polymorphism was significantly correlated to C0/D' of cyclosporine injection, and the C0/D' of patients with *1/*1 genotype was significantly higher than patients of *18B/*18B genotype; but CYP3A5*3, ABCB1(C1236T, G2677T/A, C3435T), PXR C5705T, PXR C39823T, NFKB1-94 ins/del ATTG and POR*28 gene polymorphisms were not significantly correlated to C0/D' of cyclosporine injection. In the final regression model, hemoglobin and CYP3A4*18B gene polymorphisms were significantly correlated to C0/D' of cyclosporine injection. Conclusion Cyclosporine injection can effectively improve the serum creatinine level in patients with subclinical or critical rejection; CYP3A4*18B gene polymorphism is significantly correlated to C0/D' of cyclosporine injection.

Compound Compatibility Law of Rhubarb and Aconite Decoction Based on CYP450 Enzymes / 中国药学杂志

OBJECTIVE: To study the law of compatibility and detoxification of rhubarb and aconite decoction based on the CYP450 enzyme-mediated metabolic interaction. METHODS: The activities of CYP1A2 and CYP3A4 enzymes were determined by incubating the "Cocktail" probe drugs in vitro. The total content of CYP450 enzyme in liver microsomes was determined by carbon monoxide differential method. And the expression of CYP1A2 and CYP3A4 mRNA was detected by RT-PCR method. RESULTS: Rhubarb group, aconite root combined with rhubarb group and rhubarb combined with asarum group showed significant induction effects on CYP1A2 enzyme activity. CYP1A2 enzyme activity was significantly inhibited in the aconite root combined with asarum group. CYP3A4 enzyme activity was significantly inhibited in the asarum group and the aconite root combined with asarum group. Rhubarb group, rhubarb combined with asarum group and rhubarb and aconite decoction had significant induction effects on CYP3A4 enzyme activity. Rhubarb group significantly induced the total content of CYP450 enzyme, asarum group and aconitum root combined with asarum group inhibited the total content of CYP450 enzyme, rhubarb and aconite decoction had slight induction effects on the total content of CYP450, but there was no significant difference. Rhubarb group, rhubarb combined with asarum group and rhubarb and aconite decoction group could up-regulate the mRNA expression of CYP1A2. In addition, rhubarb and aconite decoction and rhubarb group could up-regulate the mRNA expression of CYP3A4. And asarum group and aconite combined with asarum group could down-regulate the mRNA expression of CYP3A4. CONCLUSION: The drug combination weakened the strong induction of CYP1A2 and CYP3A4 enzymes by rhubarb alone, reflecting the holism concept of compound traditional Chinese medicine. The effects of rhubarb and aconite decoction on CYP3A4 enzyme activity are likely to be regulated by the mRNA levels of CYP3A4 enzyme. Whether there is correlation between the cold-heat compatibility based on the pharmacological theory and the induction or inhibition of CYP450 enzyme needs further study.

Role of kaempferol to increase bioavailability and pharmacokinetics of nifedipine in rats / 中国天然药物

Herein, the purpose of this study is to evaluate the effects of kaempferol on bioavailability and pharmacokinetics of nifedipine and its metabolite dehydronifedipine in rats. The experimental design is based on with or without kaempferol in the oral and intravenous administration of nifedipine in rats. Moreover, the pharmacokinetic parameters including nifedipine and dehydronifedipine were evaluated in rats.The in vitro studies ofkaempferol were investigated on P-glycoprotein (P-gp) and cytochrome P450 (CYP) 3A4 activity. Kaempferol reduced a 50% inhibitory concentration (IC) of 8.6 μmol·L on CYP3A4 enzyme activity. Moreover, kaempferol clearly improved the cell internalization of rhodamine-123 in MCF-7/ADR cells overexpressing P-gp. Depending on increased concentrations of kaempferol, the areas under the plasma concentration-time curve (AUC) and the peak concentration (C) of nifedipine were increased after oral and intravenous administration. Moreover, the absolute bioavailability (AB) and relative bioavailability (RB) of nifedipine in the presence of kaempferol was significantly higher than those of the control group after oral and intravenous administration. Improvement of bioavailability of nifedipine by kaempferol may be mainly because of the inhibition of the P-gp-mediated efflux transporter in the small intestine and CYP3A4-mediated metabolism in the small intestine or liver, or both.

The influence of CYP3A4 polymorphism in sex steroids as a risk factor for breast cancer / Influência do polimorfismo do gene CYP3A4 nos esteroides sexuais como fator de risco para câncer de mama

Abstract Objective Epidemiological studies have shown evidence of the effect of sex hormones in the pathogenesis of breast cancer, and have suggested a relationship of the disease with variations in genes involved in estrogen synthesis and/or metabolism. The aim of the present study was to evaluate the association between the CYP3A4*1B gene polymorphism (rs2740574) and the risk of developing breast cancer. Methods In the present case-control study, the frequency of the CYP3A4*1B gene polymorphism was determined in 148 women with breast cancer and in 245 women without the disease. The DNA of the participants was extracted from plasma samples, and the gene was amplified by polymerase chain reaction. The presence of the polymorphism was determined using restriction enzymes. Results After adjusting for confounding variables, we have found that the polymorphism was not associated with the occurrence of breast cancer (odds ratio = 1.151; 95% confidence interval: 0.714-1.856; p= 0.564). We have also found no association with the presence of hormone receptors, with human epidermal growth factor receptor 2 (HER2) overexpression, or with the rate of tumor cell proliferation. Conclusion We have not observed a relationship between the CYP3A4*1B gene polymorphism and the occurrence of breast cancer.

Resumo Objetivo Estudos epidemiológicos têm mostrado evidências da influência dos hormônios sexuais na patogênese do câncer de mama, e têm sugerido uma relação entre a doença e variações em genes envolvidos na síntese e/ou metabolização de estrógenos. O objetivo do presente estudo foi avaliar a associação entre o polimorfismo do gene CYP3A4*1B (rs2740574) e o risco de desenvolvimento da neoplasia mamária. Métodos No presente estudo de caso-controle, a frequência de polimorfismo do gene CYP3A4*1B foi determinada em 148 mulheres com câncer de mama, e em 245 mulheres sem a doença. O DNA das participantes foi extraído do plasma, e o gene foi amplificado por meio de reação em cadeia da polimerase, enquanto o polimorfismo foi determinado por enzimas de restrição. Resultados O polimorfismo, após o ajuste para variáveis de confusão, não foi associado à ocorrência de câncer de mama (razão de possibilidades = 1,151; intervalo de confiança de 95%: 0,714-1,856; p= 0,564). Também não observamos associação com a presença de receptores hormonais, superexpressão do receptor tipo 2 do fator de crescimento epidérmico humano (HER2, na sigla em inglês), ou com a taxa de proliferação celular do tumor. Conclusão Não observamos relação entre o polimorfismo do gene CYP3A4*1B e a ocorrência de câncer de mama.

Protective Effects of Matrine on α-Naphthl Isocyanate-Induced Cholestatic Liver Injury in Rats / 中国药学杂志

OBJECTIVE: To investigate the preventive protective effect of matrine(MT) on α-naphthl isocyanate(ANIT)-induced cholestasis in rat, and to explore its possible mechanism. METHODS: Thirty SD rats were randomly divided into five groups with six rats in each group: normal control group, model group, low dose matrine(5 mgkg-1), high dose matrine group(10 mgkg-1) and positive control group(ursodeoxycholic acid 100 mgkg-1), which were administered continuously for 7 d. All groups except the normal control group were given 60 mgkg-1 ANIT at the fifth day. After the last administration, all rats were fasted 24 h and arterial blood were collected to detect the indexes of total bilirubin(TBIL), aspartate aminotransferase(AST), alanine aminotransferase(ALT) and alkaline phosphatase(ALP). The livers were picked for HE staining, immunohistochemistry(IHC) analysis and Western blot(WB), to indentify the protein expressions of CYP3A4 and PXR. RESULTS: Compared to model group, low-dose and high-dose matrine decreased TBIL, AST, ALT and ALP significantly; IHC analysis showed that the expression of CYP3A4 in high-dose group was significantly higher than that in model group(P<0.05). The results of WB showed that the expressions of CYP3A4 and PXR in two matrine groups were significantly higher than that in model group(P<0.05), however, only CYP3A4 expression in UDCA group was significantly higher than that in model group(P<0.05). CONCLUSION: Matrine could improve cholestatic liver injury in rats and its mechanism might be related to the upregulation of CYP3A4 expression controled by inducing PXR expression.

Pharmacokinetics of nifedipine matrix sustained-release pellets in rats and the relationship with CYP3A4 / 中国药科大学学报

@#To conduct the characterization of its pharmacokinetics in rats of nifedipine sustained-release pellets and to study the relationship between the pellets and CYP3A4 activity. A gradient HPLC method was developed to simultaneously determine 6β-hydroxycortisol and hydrocortisone. CYP3A4 activity of rats was quantified by urinary ratio of 6β-hydroxycortisol/hydrocortisone after intravenous injection of hydrocortisone as a biomarker. HPLC method was also developed to quantify the drug concentration in plasma of rats, and the studies of pharmacokinetics were performed after oral administration of single dose of two formulations: Nifedipine matrix sustained-release pellets and nifedipine tablet(using as control). The results showed that the ratio of ten rats was 0. 271±0. 129. cmax of nifedipine sustained-release pellets decreases by nearly 70%, tmax significantly increased by 400% and t1/2 and MRT significantly increased by 230% compared to control. Nifedipine sustained-release pellets had a significant sustained-release property compared to the control and CYP3A4 activity affected its pharmacokinetics behavior.

Effect of six components in Polygoni Multiflori Radix on regulation of CYP3A4 mediated by human pregnane X receptor / 中国中药杂志

This paper aimed to study the six chemical components of Polygoni Multiflori Radix (gallic acid, quercetin, luteolin, kaempferol, resveratrol, apigenin). By the established pregnane X receptor (human pregnant X receptor, PXR) CYP3A4 mediated drug induced rapid screening technique, the effect of chemical components on the cell activity was detected by MTS cell method, and the value of IC₅₀ was calculated. The dual luciferase reporter system was used to co-transfect PXR reporter gene expression vector containing transcriptional regulation and CYP3A4 with HepG2 cells, with 10 μmol·L⁻¹ rifampicin (RIF) as a positive control, and 10 μmol·L⁻¹ of ketoconazole (TKZ) as negative control. Gallic acid, quercetin, luteolin, kaempferol, apigenin, resveratrol(5, 10, 20 μmol·L⁻¹) were used to incubate for 24 h, and the luciferase activity was detected. The results showed that when plasmid pcDNA3.1 was co-transfected with pGL4.17-CYP3A4, gallic acid and resveratrol had an inhibitory effect on the regulation of CYP3A4, and quercetin, luteolin, kaempferol had an inductive effect on CYP3A4; when pcDNA3.14-PXR was co-transfected with pGL4.17-CYP3A4, quercetin, luteolin, kaempferol, apigenin, resveratrol had an inductive effect. To sum up, the 6 reported liver injury components had inhibitory or activating effects on CYP3A4. After PXR plasmid was involved, 5 components had an inductive effect on CYP3A4, and the inductive effects of 2 components were significantly different. In this experiment, we found that 2 kinds of potential liver injury components in Polygoni Multiflori Radix had been induced by CYP3A4, which was achieved through PXR regulation. It suggested that attention shall be paid to potential drug interactions when combined with Polygoni Multiflori Radix, so as to improve the safety and efficacy.

Mechanism of Berberine in the Regulation of CYP3A4 and P-gp via PXR Signaling Pathway / 中国药师

Objective: To investigate the regulation of CYP3A4 and P-gp by berberine hydrochloride ( BBR) via pregnane X re-ceptor (PXR) pathway. Methods: pLKO. 1-PXR vector, a lentivirus plasmid expressing PXR shRNA, was packaged into 293T cells. Human hepatoma (HepG2) cells were infected with the lentivirus and the cell clones stably expressing PXR shRNA were selected by puromycin according to pLKO. 1 vector characteristics. Real-time RT-PCR and Western blot were used to evaluate CYP3A4 and P-gp mRNA and protein in berberine treated HepG2 cells and PXR-silenced HepG2 cells. Results: The PXR expression in PXR silenced cells significantly decreased (P<0.01) when compared with that in HepG2 cells, while there was no significant difference (P >0. 05) in the expression of CYP3A4 and P-gp between the groups. Compared with that in HepG2 cells, the inhibition of berberine on the mRNA and protein expression of CYP3A4 and P-gp in PXR-silenced HepG2 cells was weakened (P<0. 05 or P<0. 01). Conclu-sion: Berberine can regulate the expression of CYP3A4 and P-gp via PXR signaling pathway, while it is not the only one.

Impact of CYP3A4*1G Polymorphism on Fentanyl Analgesia Assessed by Analgesia Nociception Index in Chinese Patients Undergoing Hysteroscopy / 中华医学杂志(英文版)

<p><b>Background</b>The clinical efficacy of fentanyl for pain control differs greatly across individuals. The purpose of this study was to investigate the impact of CYP3A4*1G polymorphism including wild-type homozygote (CYP3A4*1/*1, GG), mutant heterozygote (CYP3A4*1/*1G, GA), and mutant homozygote (CYP3A4*1G/*1G, AA) on fentanyl analgesia in Chinese patients undergoing hysteroscopy by the assessment of analgesia nociception index (ANI).</p><p><b>Methods</b>A total of 200 gynecologic patients scheduled for elective hysteroscopy under general anesthesia at Peking University People's Hospital from May to December in 2017 were enrolled in this study. Venous blood was withdrawn for genotyping of CYP3A4*1G before operation. Fentanyl 1 μg/kg was administered preoperatively followed by target-controlled infusion of propofol for induction and maintenance. Intraoperative analgesic efficacy of fentanyl was assessed by ANI monitoring at T0 (entering room), T1 (cervical dilation), T2 (start of cervical aspiration), and T3 (end of cervical aspiration) time points. The duration of propofol infusion and total dosage of propofol were recorded as well.</p><p><b>Results</b>The patients were divided into three groups according to CYP3A4*1G polymorphism, including 143 in GG group, 47 in GA group, and 10 in AA group. There was no significant difference in clinical demographics among three groups. The frequency of CYP3A4*1G variant alleles accounted for 16.8% and the distribution of variant alleles was consistent with Hardy-Weinberg equilibrium. Using a multilevel model, ANI values at T1 (63.81 ± 19.61), T2 (63.63 ± 17.82), and T3 (65.68 ± 17.79) were significantly lower than that at T0 (77.16 ± 12.93) in the study population (F = 23.50, P < 0.001), suggesting that higher levels of pain at T1, T2, and T3 than T0. Patients with GG genotype showed significantly lower ANI than those with GA or AA genotypes during hysteroscopy under the same dose of fentanyl.</p><p><b>Conclusion</b>CYP3A4*1G polymorphism associated with the analgesic efficacy of intraoperative fentanyl in the patients undergoing hysteroscopy under general anesthesia.</p>

Effects of Coix-seed Reactive Derivatives (CRD) on Cytochrome P450 Isoforms CYP3A4, CYP2D6, CYP2C9 In Vitro / 日本補完代替医療学会誌

CRD, a Coix-seed Reactive Derivatives, has a novel mechanism in the treatment of various diseases. In the present study, a fluorometric-based high throughput method using cytochrome P450 (CYP)screening kit was adopted to evaluate in vitro inhibition potential of CRD (CRD 1 and CRD 2) on CYP isoenzymes by calculating remaining enzyme activities and inhibitory potential (IC50 values) using the determined values of fluorescence intensity. IC50　of CRD 1 and CRD 2 were as follows: CYP3A4; >500 µg/ml, 490 µg/ml, CYP2D6; >500 µg/ml，>500 µg/ml，CYP2C9; >500 µg/ml，339 µg/ml, respectively. The result showed that CRD exhibited little activity in the inhibition of CYP3A4, CYP2D6 and CYP2C9.