Changes in pharmacokinetics of single dose of fentanyl in simulated high altitude in rats / 陆军军医大学学报

Objective To explore the pharmacokinetic changes of single dose of fentanyl in rats in a simulated high-altitude and contributing factors.Methods Thirty-six healthy female SD rats(6～8 weeks old,250±20 g)were randomly divided into high-altitude-acute-exposure group(group A),high-altitude-chronic-exposure group(group S)and control group(group C)through random number table,with 12 rats in each group.The group A and S were housed in a low-pressure chamber simulating the high altitude of 5000 m above sea level for 3 and 30 d respectively,and the group C was housed out of the chamber(at an altitude of 300 m).A single dose of fentanyl was administered through the femoral vein to 6 rats randomly selected from each group.Liquid chromatography tandem mass spectrometry(LC-MS/MS)was used to detect blood concentrations of fentanyl and WinNonlin 8.2 software was used to calculate the pharmacokinetic parameters,while blood samples were taken through the femoral artery before and in 1,2,4,8,15,30,60,120 and 180 min after administration.The remaining 6 rats were ultrasonographically assessed for portal vein internal diameter(PVD),peak flow velocity(PVV)and blood flow(PVF),and liver tissues were collected for CYP3A1 protein content assay.Results The blood drug concentrations of fentanyl in the group A and group S were significantly lower than those in the group C at 60,120,and 180 min(P=0.002,P＜0.001,P= 0.001).Compared with the group C,the clearance rate(CL)of the group A was increased by 54.06%(P=0.021),and the mean residence time(MRTlast)was shortened by 24.21%(P=0.033);CL of the group S was increased by 50.10%(P=0.041),the area under the concentration-time curve(AUC0-t,AUC0-∞)and MRTlast were reduced by 18.92%(P=0.039),27.54%(P=0.018)and 33.61%(P= 0.004),respectively.PVD and PVF in the group S increased by 10.87%(P=0.006)and 42.50%(P= 0.006)when compared with the group C.The CYP3A1 protein content in the group A was 28.74%,which was higher than that in the group C(P=0.048).Conclusion Fentanyl is cleared significantly faster after a single dose in rats in simulated high-altitude,which may be related to the increased liver blood flow and increased CYP3A1 protein expression in liver.

Correlation between CYP3A5*3 Gene Polymorphism and Adverse Reactions of Apatinib Monotherapy in Patients with Advanced Gastric Cancer / 现代检验医学杂志

Objective To investigate the relationship between cytochrome P450 3A5*3(CYP3A5*3)gene polymorphism and adverse reactions of apatinib monotherapy in advanced gastric cancer patients.Methods A total of 86 patients with advanced gastric cancer who received apatinib monotherapy at Nanjing First Hospital from January 2020 to June 2022 were selected,and 2 ml of peripheral venous blood from patients was collected.The genotype of CYP3A5*3 was identified using PCR-RFLP combined sequencing method,and its correlation with adverse reactions was analyzed by apatinib.Results Among the 86 patients,there were 29 cases of mutant heterozygous genotype(AG genotype)and 51 cases of mutant homozygous genotype(GG genotype),with a mutation type accounting for 93.02％.The incidence of hypertension and leukopenia in patients with the CYP3A5*3 GG genotype was significantly higher than in patients with the AA+AG genotype(χ2=6.154,6.947,P=0.043,0.027).Other adverse reactions related to apatinib treatment were not found to be associated with the CYP3A5*3 genotype(P＞0.05).In addition,no correlation was found between severe adverse reactions and the CYP3A5*3 genotype(P＞0.05).Conclusion The CYP3A5*3 GG genotype significantly increased the risk of hypertension and leukopenia caused by apatinib monotherapy,and no correlation was found with the risk of serious adverse reactions.

Effects of CYP3A5 gene polymorphism and Wuzhi capsule on early postoperative tacrolimus exposure and adverse reactions in renal transplant patients / 中国药房

OBJECTIVE To investigate the effects of CYP3A5 gene polymorphism and Wuzhi capsule （WZ） on early postoperative tacrolimus exposure and adverse reactions in renal transplant patients. METHODS A total of 132 patients who underwent renal transplantation and received tacrolimus + mycophenolic acids + prednisone after operation in our hospital from September 2021 to September 2023 were selected and divided into four groups according to genotypes （CYP3A5*1 or CYP3A5*3/*3） and with or without WZ （“ +WZ” meant drug combination， “ +NO WZ” meant without combination）. The blood trough concentration/daily dose （c0/D） values of the four groups were analyzed on the 14th day， 1 month and 3 months after renal transplantation. The incidence of acute rejection and the incidence of tacrolimus-related adverse reactions within 3 months after transplantation were compared among 4 groups. RESULTS On the 14th day， 1 month and 3 months after surgery （except for the CYP3A5*1+WZ group）， c0/D values of CYP3A5*1 genotype patients were significantly lower than those of CYP3A5*3/*3 genotype patients regardless of whether they were treated with WZ additionally （P＜0.05）. Within 3 months after surgery， although there was no significant difference in the incidence of acute rejection and tacrolimus-related adverse reactions among the four groups （P＞ 0.05）， the incidence of hyperglycemia in patients with CYP3A5*3/*3 was higher （41.67%）. CONCLUSIONS CYP3A5 gene polymorphism is significantly related to tacrolimus c0/D in kidney transplant patients. Under the premise of c0 monitoring of tacrolimus， patients with CYP3A5*1 genotype should be given WZ as soon as possible after surgery to accelerate tacrolimus to reach the therapeutic concentration range， while CYP3A5*3/*3 genotype is not recommended to be given WZ because of the higher risk of hyperglycemia.

Using Package Inserts to Disseminate Information Regarding Drug Interactions Mediated by CYP3A Inhibition: Status and Issues / 医薬品情報学

Objective: In Japan, the Guideline on Drug Interaction for Drug Development and Appropriate Provision of Information (GL) was notified in 2018. In the GL and the associated document, it was determined that package inserts of drugs which need to be categorized as precaution due to the significant degree of drug interactions by CYP3A inhibition should describe possible perpetrator drugs using designated expressions, such as “strong CYP3A inhibitor.” For contraindication, it was decided that all drugs should be described individually. In 2021, as supplementary information to the GL, a list of CYP substrates, inhibitors and inducers, classified based on interaction strength and CYP isoenzymes (i.e., the drug list), was published. In this study, we aimed to survey the information on drug interactions by CYP3A inhibition described in the package inserts based on information in the drug list, and to clarify the status and issues.Methods: The package inserts of 24 substrate drugs of CYP3A with contraindications for itraconazole, a strong CYP3A inhibitor, were examined, and the descriptions of strong, moderate, and other CYP3A inhibitors were studied.Results: The frequencies of contraindication for strong CYP3A inhibitors were cobicistat (75%), grapefruit juice (0%), ritonavir (92%), voriconazole (67%), clarithromycin (50%), ceritinib (0%), and posaconazole (33%). On the other hand, some CYP3A substrate drugs was contraindicated with moderate CYP3A inhibitors but not with these strong CYP3A inhibitors. Furthermore, 19 CYP3A inhibitors, which were not on the drug list published in 2021, were identified as contraindications for co-administration. Majority of these were protease inhibitors, and some have been discontinued or not available in Japan.Conclusion: The findings of this study imply the necessity of organizing scientific description based on the GL strength classification. Moreover, it is important to disseminate the information and precautions for drug interactions provided in the package inserts to medical practice.

Effect of γ-ray on metabolic enzyme CYP3A1 in rat liver on multiple levels / 中国药理学通报

Aim To explore the effect of γ-ray on the mRNA,protein expression levels and metabolic activity level of the key drug metabolic enzyme CYP3A1 in rat liver. Methods Wistar rats were randomly divided into control group, 24 h post-radiation group and 72 h post-radiation group. The experimental group was exposed to total body irradiation of single 6 Gy γ-ray. Blood was collected from the orbital venous plexus for blood routine examination and biochemical analysis 24 h and 72 h after irradiation, and liver tissue was prepared for quantifying expression of CYP3A1 mRNA and liver-specific microRNA (miR-122-5p) through RT-PCR. The expression level of CYP3A1 protein was analyzed by Western blot, and the metabolic activity level of CYP3A1 detected by the specific substrate midazolam combined with LC-MS method. Results Com¬pared with the control group, the weights of the rats in the radiation group significantly decreased, and the number of white blood cells was markedly reduced. Simultaneously, the activities of alanine aminotrans-ferase and alkaline phosphatase continuously descended, as well as the levels of total bilirubin and bile acid significantly increased, which indicated that the liver may be damaged after radiation. The relative expression of CYP3A1 mRNA continued to increase significantly 24 h and 72 h after irradiation. CYP3A1 protein expression and metabolic activity levels showed an obvious increasing trend 24 h after irradiation, and rose significantly 72 h after irradiation compared with the control group. At the same time, the expression of miR-122-5p in liver of rats in the 24 h and 72 h post-radiation group continued to decrease rapidly compared with the control group. Conclusions γ-ray radiation may arouse damage effect on liver, which leads to the continuous up-regulation of the mRNA and protein expression levels of the capital metabolic enzyme CYP3A1 in liver tissue, as well as the elevation of the metabolic activity level. The regulatory mechanism might be related to miR-122-5p.

Effects of single nucleotide polymorphism of drug metabolizing enzyme cytochrome P450 on the efficacy of inhaled cortisol hormone in asthmatic children / 中国临床药理学与治疗学

AIM: To elucidate the relationship between childhood asthma susceptibility and clinical efficacy of inhaled glucocorticoids (ICS) in children with different genotypes of asthma by exploring rs776746 and rs15524 single nucleotide polymorphisms (SNPs) of cytochrome P450 enzyme 3A5 (CYP3A5) gene in asthmatic children and healthy children. METHODS: The CYP3A5 gene rs776746 and rs15524 polymorphic sites were detected in 79 children (Case group) with asthma of Han nationality and 100 healthy children (Control group) who met the inclusion criteria admitted to the Northern Theater General Hospital in Northeast China from October 2016 to October 2020, and genotype, allele and linkage analysis were performed. The case group was given inhaled glucocorticoids by nebulised inhalation for 3 months, and lung function and exhaled breath nitric oxide (FeNO) were measured at entry and after treatment, and asthma control score C-ACT/ACT was done after treatment, so as to compare the prevalence of different genotypes and the differences in the above test index scores. RESULTS: There was complete linkage disequilibrium at rs776746 and rs15524 loci. There were three genotypes of T/T, T/C and C/C at rs776746 locus of CYP3A5 gene. There were significant differences in the frequency of different genotypes between the case group and the control group (χ

Glutaredoxin-1 alleviates acetaminophen-induced liver injury by decreasing its toxic metabolites / 药物分析学报

Excessive N-acetyl-p-benzoquinone imine(NAPQI)formation is a starting event that triggers oxidative stress and subsequent hepatocyte necrosis in acetaminophen(APAP)overdose caused acute liver failure(ALF).S-glutathionylation is a reversible redox post-translational modification and a prospective mechanism of APAP hepatotoxicity.Glutaredoxin-1(Glrx1),a glutathione-specific thioltransferase,is a primary enzyme to catalyze deglutathionylation.The objective of this study was to explored whether and how Glrx1 is associated with the development of ALF induced by APAP.The Glrx1 knockout mice(Glrx1-/-)and liver-specific overexpression of Glrx1(AAV8-Glrx1)mice were produced and underwent APAP-induced ALF.Pirfenidone(PFD),a potential inducer of Glrx1,was administrated preceding APAP to assess its protective effects.Our results revealed that the hepatic total protein S-glutathionylation(PSSG)increased and the Glrx1 level reduced in mice after APAP toxicity.Glrx1-/- mice were more sensitive to APAP overdose,with higher oxidative stress and more toxic metabolites of APAP.This was attributed to Glrx1 deficiency increasing the total hepatic PSSG and the S-glutathionylation of cytochrome p450 3a 11(Cyp3a11),which likely increased the activity of Cyp3a11.Conversely,AAV8-Glrx1 mice were defended against liver damage caused by APAP overdose by inhibiting the S-glutathionylation and activity of Cyp3a11,which reduced the toxic metabolites of APAP and oxidative stress.PFD precede administration upregulated Glrx1 expression and alleviated APAP-induced ALF by decreasing oxidative stress.We have identified the function of Glrx1 mediated PSSG in liver injury caused by APAP overdose.Increasing Glrx1 expression may be investigated for the medical treatment of APAP-caused hepatic injury.

The F-box-only protein 44 regulates pregnane X receptor protein level by ubiquitination and degradation

Pregnane X receptor (PXR) is a ligand-activated nuclear receptor that transcriptionally upregulates drug-metabolizing enzymes [e.g., cytochrome P450 3A4 (CYP3A4)] and transporters. Although the regulation of PXR target genes is well-characterized, less is known about the regulation of PXR protein level. By screening an RNAi library, we identified the F-box-only protein 44 (FBXO44) as a novel E3 ligase for PXR. PXR abundance increases upon knockdown of FBXO44, and, inversely, decreases upon overexpression of FBXO44. Further analysis revealed that FBXO44 interacts with PXR, leading to its ubiquitination and proteasomal degradation, and we determined that the F-box associated domain of FBXO44 and the ligand binding domain of PXR are required for the functional interaction. In summary, FBXO44 regulates PXR protein abundance, which has downstream consequences for CYP3A4 levels and drug-drug interactions. The results of this study provide new insight into the molecular mechanisms that regulate PXR protein level and activity and suggest the importance of considering how modulating E3 ubiquitin ligase activities will affect PXR-mediated drug metabolism.

Activation of PXR causes drug interactions with Paxlovid in transgenic mice

Paxlovid is a nirmatrelvir (NMV) and ritonavir (RTV) co-packaged medication used for the treatment of coronavirus disease 2019 (COVID-19). The active component of Paxlovid is NMV and RTV is a pharmacokinetic booster. Our work aimed to investigate the drug/herb-drug interactions associated with Paxlovid and provide mechanism-based guidance for the clinical use of Paxlovid. By using recombinant human cytochrome P450s (CYPs), we confirmed that CYP3A4 and 3A5 are the major enzymes responsible for NMV metabolism. The role of CYP3A in Paxlovid metabolism were further verified in Cyp3a-null mice, which showed that the deficiency of CYP3A significantly suppressed the metabolism of NMV and RTV. Pregnane X receptor (PXR) is a ligand-dependent transcription factor that upregulates CYP3A4/5 expression. We next explored the impact of drug- and herb-mediated PXR activation on Paxlovid metabolism in a transgenic mouse model expressing human PXR and CYP3A4/5. We found that PXR activation increased CYP3A4/5 expression, accelerated NMV metabolism, and reduced the systemic exposure of NMV. In summary, our work demonstrated that PXR activation can cause drug interactions with Paxlovid, suggesting that PXR-activating drugs and herbs should be used cautiously in COVID-19 patients receiving Paxlovid.

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 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.

Effects of Gelsemium elegans Combined with Mussaenda pubescens on Transporter BCRP and Drug-metabolizing Enzyme CYP3A11 / 中国实验方剂学杂志

ObjectiveTo explore the effect of Gelsemium elegans combined with Mussaenda pubescens on efflux transporter breast cancer resistance protein （BCRP） and cytochrome P450 3A11 （CYP3A11） and their attenuation mechanism， and to investigate whether the nuclear receptors were involved in such regulation by intervening it with nuclear receptor activators. MethodC57BL/6 mice were divided into the blank group， G. elegans （GE， 0.25 g·kg-1）group， GE + M. pubescens （MP） （0.25 g·kg-1+10 g·kg-1） group， GE + pregnane X receptor （PXR） activator （rifampicin）（GE + Rif，0.25 g·kg-1+50 mg·kg-1） group， GE + MP + Rif （0.25 g·kg-1+10 g·kg-1+50 mg·kg-1） group， GE + constitutive androstane receptor （CAR） activator （1，4-Bis ［2-（3，5-Dichloropyridyloxy）］ benzene， TCPOBOP）（GE + TCP， 0.25 g·kg-1+0.5 mg·kg-1） group， and GE + MP + TCP （0.25 g·kg-1+10 g·kg-1+0.5 mg·kg-1） group. The medication lasted for 14 successive days. One hour after the last administration， the mice were sacrificed by cervical dislocation and the liver tissue was harvested. The left liver tissue was stained with hematoxylin- eosin （HE） for observing the pathological changes. The right liver tissue was used for BCRP and CYP3A11 mRNA and protein expression detection by real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） and Western blot. ResultThe survival rates of mice in the GE + Rif group， GE group， and GE + MP group were 25% （the lowest）， 40%， and 80%， respectively， and no death was observed in the other groups. Compared with the obvious lesions in the liver cells of the GE group， the pathological changes in liver cells of the GE + MP group were alleviated， while those in the GE + Rif group were worsened. Compared with the GE + Rif group， the GE + MP + Rif group exhibited relieved pathological changes in liver cells. Both the GE + TCP group and the GE + MP + TCP group showed mild liver lesions. The comparison with the GE + MP group revealed that the pathological changes in the GE + MP + TCP group were slightly relieved. Compared with the blank group， the expression of BCRP protein and mRNA in GE group were significantly decreased （P<0.05，P<0.01）.The expression of CYP3A11 protein in GE group were significantly decreased （P<0.01）. Compared with the GE group， the GE + MP group displayed remarkably up-regulated BCRP protein and mRNA expression （P<0.05，P<0.01） and CYP3A11 protein expression （P<0.05）， but slightly up-regulated CYP3A11 mRNA expression. Compared with the GE group， the GE + Rif group exhibited down-regulated BCRP protein expression （P < 0.05）. The protein and mRNA expression levels of BCRP were lower in the GE + MP + Rif group than in the GE + MP group （P<0.05，P<0.01）. The PXR activator rifampicin regulated BCRP before and after the combination of G. elegans with M. pubescens. The CYP3A11 protein and mRNA expression levels in the GE + TCP group were higher than those in the GE group （P<0.05，P<0.01）. Compared with the GE + MP group， the GE + MP + TCP group showed up-regulated CYP3A11 protein and mRNA expression （P<0.05，P<0.01）. CAR activator TCPOBOP also had a regulatory effect on CYP3A11 before and after the compatibility of G. elegans with M. pubescens. ConclusionThe attenuated toxin after the combination of G. elegans with M. pubescens is closely related to the efflux transporter BCRP and the drug-metabolizing enzyme CYP3A11.

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.

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.

Effect of CYP3A5 and MDR1 gene polymorphism on blood concentration of tacrolimus and creatinine level in uremic patients during the early phase of kidney transplantation / 药学实践杂志

Objective To investigate the effect of CYP3A5 and MDR1 gene polymorphisms on blood concentration of tacrolimus and creatinine level in uremic patients during the early phase after kidney transplantation in real clinical practice. Methods 131 patients who underwent kidney transplantation for the first time with triple immunotherapy based on tacrolimus in single-center from 2013 to 2017 were enrolled for retrospective study. Tacrolimus daily dose, blood concentration, blood concentration-to-dose ratio, and serum level were compared according to the various genotypes of CYP3A5 and MDR1 polymorphisms in renal transplantation recipients, respectively. Results The dosage of tacrolimus in CYP3A5*3/*3 (GG) kidney transplantation recipients within 4 weeks after kidney transplantation was lower than those of CYP3A5*1/*1 (AA) and CYP3A5*1/*3 (AG). The serum creatinine levels of patients whose tacrolimus concentration in the range of 10-13 ng/ml were close to the normal value. Conclusion CYP3A5 gene polymorphism affects the blood concentrations of tacrolimus in renal transplant recipients. No association has been found between the blood concentrations of tacrolimus and MDR1 gene polymorphism. Tacrolimus concentration in the range of 10-13 ng/ml might contribute to restore the early kidney graft function.

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.

Individualized precision therapy for patients with ischemic stroke and hypertension / 中国临床药理学与治疗学

AIM: To investigate the influence of CYP3A5 gene polymorphism on the anti-hypertensive efficacy of calcium channel blocker in patients with ischemic stroke and hypertension. METHODS: A total of 108 cases of ischemic stroke patients with hypertension were included and divided into experimental group and control group, and 54 cases in each group, the experimental group selected amlodipine tablets and levamlodipine tablets respectively according to the results of genetic testing, while the control group selected amlodipine tablets, which in order to investigate the antihypertensive efficacy of the two groups. RESULTS: The effective rate of experimental group and control group was 77.78% and 57.41% (P 0.05). In the experimental group, the antihypertensive effect of GG and AG genotype patients after taking amlodipine tablets was significantly higher than that of AA type patients, and GG type patients had a stronger antihypertensive effect than AG type patients after taking amlodipine tablets. CONCLUSION: CYP3A5 gene polymorphism is very important for blood pressure control by calcium channel blockers in patients with ischemic stroke and hypertension.

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.

Analysis on Mechanism of Adenine-induced Kidney-Yang Deficiency Rats Treated with Different Processed Products of Curculiginis Rhizoma / 中国实验方剂学杂志

Objective:To study on the mechanism of invigorating kidney and strengthening Yang of different processed products of Curculiginis Rhizoma aqueous extracts in rats with kidney-Yang deficiency induced by adenine. Method:Taking Guifu Dihuang pills as the positive drug group (the dosage of 2.466 g·kg-1), after intragastric administration for 4 weeks, enzyme-linked immunosorbent assay (ELISA) was used to compare the effects of different processed products of Curculiginis Rhizoma aqueous extracts (the dosage of 2.742 g·kg-1) on the levels of thyroid stimulating hormone (TSH), 17-hydroxycorticosteroids (17-OHCS), estradiol (E2), testosterone (T), triiodothyronine (T3), thyroxine (T4) and cortisol (COR) in serum of rats with kidney-Yang deficiency induced by adenine. The activity of cytochrome P450 3A (CYP3A) in rat liver and kidney microsomes was determined by Nash colorimetry. Result:All the processed products aqueous extracts could improve the function of hypothalamus-pituitary-target gland axis in rats with kidney-Yang deficiency induced by adenine, and the total score was in the order of Euodiae Fructus juice-processed products (29 points)>salt-processed products (25 points)>rice wine-processed products (23 points)>raw products (17 points)>Zingiberis Rhizoma juice-processed products (11 points). And the different processed products of Curculiginis Rhizoma could increase CYP3A activity of liver and kidney microsomes of kidney-Yang deficiency rats, especially the Euodiae Fructus juice-processed products and salt-processed products. Conclusion:All the processed products of Curculiginis Rhizoma can effectively treat the syndrome of kidney-Yang deficiency in rats, among them, Euodiae Fructus juice-processed products and salt-processed products have more significant effect on invigorating kidney and strengthening Yang.

Effect of wuzhi capsules on the blood concentration of tacrolimus relative to diltiazem and CYP3A5 gene polymorphisms / 药学学报

To determine the relationship between the effect of wuzhi capsules on the blood concentration of tacrolimus as compared to diltiazem and with regard to cytochrome P450 (CYP)3A5 gene polymorphisms, 170 patients who underwent renal transplantation from November 2014 to March 2018 and used tacrolimus combined with diltiazem 30 mg bid were selected in this study retrospectively. Patients were divided into an observation group (105 patients) and a control group (65 patients) according to whether they used wuzhi capsules after the operation. The polymorphisms of CYP3A5*3 were determined and the effect of wuzhi capsules on the blood concentration of tacrolimus, as compared with that of diltiazem was determined in patients with different CYP3A5*3 genotypes. This study complies with relevant ethical norms. The results show that compared with diltiazem, an increase of tacrolimus C0/D was significantly correlated with the patient's CYP3A5*3 genotype in both the self-control and the control group. CYP3A5 expressers in the observation group were able to increase the tacrolimus C0/D by about 76.8% by replacing the wuzhi capsules with diltiazem, but this effect was not observed in CYP3A5 non-expressers. In CYP3A5 expressers wuzhi capsules had a greater ability relative to diltiazem to increase the blood concentration of tacrolimus.