Computational exploration of microsomal cytochrome P450 3A1 enzyme modulation by phytochemicals of Cichorium intybus L.: Insights into drug metabolism

Drug metabolism plays a crucial role in drug fate, including therapeutic inactivation or activation, as well as the formation of toxic compounds. This underscores the importance of understanding drug metabolism in drug discovery and development. Considering the substantial costs associated with traditional drug development methods, computational approaches have emerged as valuable tools for predicting the metabolic fate of drug candidates. With this in mind, the present study aimed to investigate the potential mechanisms underlying the modulation of microsomal cytochrome P450 3A1 (CYP3A1) enzyme activity by various phytochemicals found in Cichorium intybus L., commonly known as chicory. To achieve this goal, several in silico methods, including molecular docking and molecular dynamics (MD) simulation, were employed to explore computationally the microsomal CYP3A1 enzyme. Schrodinger software was utilized for the molecular docking study, which involved the interaction analysis between CYP3A1 and 28 phytoconstituents of Cichorium intybus. Virtual screening of 28 compounds from chicory led to the identification of the top five ranked compounds. These compounds were evaluated for drug-likeness properties, pharmacokinetic profiles, and predicted binding affinities to CYP3A1. Caffeoylshikimic acid and cichoric acid emerged as promising candidates due to their favorable characteristics, including good oral bioavailability and high binding affinities to CYP3A1. Molecular dynamics simulations were conducted to assess the stability of caffeoylshikimic acid within the CYP3A1 binding pocket. The results demonstrated that caffeoylshikimic acid maintained stable interactions with the enzyme throughout the simulation, suggesting its potential as an effective modulator of CYP3A1 activity. The findings of this study have the potential to provide valuable insights into the complex molecular mechanisms by which Cichorium intybus L. acts on hepatocytes and modulates CYP3A1 enzyme expression or activity. By elucidating the impact of these phytochemicals on drug metabolism, this research contributes to our understanding of how chicory may interact with drugs and influence their efficacy and safety profiles.

Effect of Gut Microbiota on the Pharmacokinetics of Nifedipine in Spontaneously Hypertensive Rats

The pharmacokinetic variability of nifedipine widely observed in the clinic cannot be fully explained by pharmacogenomics. As a new factor affecting drug metabolism, how the gut microbiota affects the pharmacokinetics of nifedipine needs to be explored. Spontaneously hypertensive rats (SHRs) have been commonly used in hypertension-related research and served as the experimental groups; Wistar rats were used as control groups. In this study, the bioavailability of nifedipine decreased by 18.62% (p < 0.05) in the SHRs compared with the Wistar rats. Changes in microbiota were associated with the difference in pharmacokinetics. The relative abundance of Bacteroides dorei was negatively correlated with AUC0-t (r = -0.881, p = 0.004) and Cmax (r = -0.714, p = 0.047). Analysis of serum bile acid (BA) profiles indicated that glycoursodeoxycholic acid (GUDCA) and glycochenodeoxycholic acid (GCDCA) were significantly increased in the SHRs. Compared with the Wistar rats, the expressions of CYP3A1 and PXR were upregulated and the enzyme activity of CYP3A1 increased in the SHRs. Spearman's rank correlation revealed that Bacteroides stercoris was negatively correlated with GUDCA (r = -0.7126, p = 0.0264) and GCDCA (r = -0.6878, p = 0.0339). Moreover, GUDCA was negatively correlated with Cmax (r = -0.556, p = 0.025). In primary rat hepatocytes, GUDCA could induce the expressions of PXR target genes CYP3A1 and Mdr1a. Furthermore, antibiotic treatments in SHRs verified the impact of microbiota on the pharmacokinetics of nifedipine. Generally, gut microbiota affects the pharmacokinetics of nifedipine through microbial biotransformation or by regulating the enzyme activity of CYP3A1.

High-altitude Hypoxia Influences the Activities of the Drug-Metabolizing Enzyme CYP3A1 and the Pharmacokinetics of Four Cardiovascular System Drugs

(1) Background: High-altitude hypoxia has been shown to affect the pharmacokinetic properties of drugs. Although there is a high incidence of cardiovascular disease among individuals living in high-altitude areas, studies on the effect of high-altitude hypoxia on the pharmacokinetic properties of cardiovascular drugs are limited. (2) Methods: The aim of this study was to evaluate the pharmacokinetics of nifedipine, bosentan, simvastatin, sildenafil, and their respective main metabolites, dehydronifedipine, hydroxybosentan, simvastatin hydroxy acid, and N-desmethyl sildenafil, in rats exposed to high-altitude hypoxia. Additionally, the protein and mRNA expression of cytochrome P450 3A1 (CYP3A1), a drug-metabolizing enzyme, were examined. (3) Results: There were significant changes in the pharmacokinetic properties of the drugs in rats exposed to high-altitude hypoxia, as evidenced by an increase in the area under the curve (AUC) and the half-life (t_1/2z) and a decrease in total plasma clearance (CL_z/F). However, most of these changes were reversed when the rats returned to a normoxic environment. Additionally, there was a significant decrease in CYP3A1 expression in rats exposed to high-altitude hypoxia at both the protein and mRNA levels. (4) Conclusions: High-altitude hypoxia suppressed the metabolism of the drugs, indicating that the pharmacokinetics of the drugs should be re-examined, and the optimal dose should be reassessed in patients living in high-altitude areas.

CYP3A1 metabolism-based neurotoxicity of strychnine in rat

Strychnine is one of the main bioactive and toxic constituents of Semen Strychni. In the present study, the neurotoxic effects of strychnine, and the role of individual differences in metabolism on susceptibility to neurotoxicity of strychnine were investigated. The acute toxicity was observed by a single dose of strychnine (2.92 mg/kg, i.g.) in rats, the epileptic stages of rats were scored according to Racine's scale. The neurotoxicity of strychnine was evaluated by the levels of ROS, MDA, SOD and GSH in hippocampus, striatum, and cortex tissues measurements and histopathological analysis. The concentrations of strychnine in the plasma, hippocampus, striatum, and cortex tissues were determined using high performance liquid chromatography tandem mass spectrometry (LC-MS/MS). The expressions of the cytochrome P450, which is the most critical protein family involved in drugs metabolism, were detected by proteomics. The mechanism of susceptibility to neurotoxicity of strychnine was elucidated by correlation analysis among above indicators. The results indicated that striatum and cortex were the main toxic targets of strychnine, and the CYP3A1 might be a susceptible biomarker to neurotoxicity of strychnine. These results provide valuable insights into the neurotoxic susceptibility of strychnine that will aid in the rational clinical use of strychnine (possibly including Semen Strychni).

Modulatory effects of Benjakul extract on rat hepatic cytochrome P450 enzymes

Benjakul, a traditional Thai formulation, has been used as a carminative and adaptogenic drug. It consists of five plants, Piper chaba Hunter, Piper sarmentosum Roxb., Piper interruptum Opiz., Plumbago indica Linn., and Zingiber officinale Roscoe, in equal ratios. Some individual herbs present in Benjakul were reported to modulate cytochrome P450 (CYP) enzymes. This study aimed to investigate the effects of Benjakul extract on the activities and mRNA expression levels of hepatic CYP2C11 and CYP3A1 in rats. Adult male rats were orally administered 200, 400, or 600 mg/kg BW Benjakul extract for 28 days. Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), blood urea nitrogen (BUN) and creatinine levels were assayed. CYP2C11 and CYP3A1 activities were analyzed using cytochrome P450 assay kits. The mRNA expression of CYP2C11 and CYP3A1 was measured using a quantitative real-time PCR assay. Benjakul treatment significantly increased the serum ALT and BUN levels. At doses of 200, 400, and 600 mg/kg BW, Benjakul treatment increased hepatic CYP3A1 activity and CYP3A1 mRNA expression. CYP2C11 mRNA expression was unchanged by treatment with Benjakul extract; however, treatment with the high and middle doses of Benjakul extract increased CYP2C11 activity. Treament with Benjakul extract induced CYP2C11 and CYP3A1 activity in rats. Concurrent use of Benjakul with conventional drugs should be considered to potentially induce herb-drug interactions.

Pharmacokinetics of omeprazole in rats with dextran sulfate sodium-induced ulcerative colitis

Omeprazole is a commonly used drug in patients with ulcerative colitis (UC). This study investigated the pharmacokinetics of omeprazole in rats with UC induced by dextran sulfate sodium (DSS). The pharmacokinetics of intravenously administered omeprazole (20 mg/kg) was investigated in normal and UC rats using LC-MS/MS. The formation of 5-OH omeprazole, a main metabolite of omeprazole, in rat liver microsomes (RLMs) from normal and UC rats was compared. The protein levels of CYP1A2, CYP2D1, and CYP3A1 in the liver were measured by Western blot. Compared with normal rats, UC rats had increased plasma concentrations of omeprazole, resulting in an increased AUC_0-240 min and decreased CL. DSS treatment decreased the formation rate of 5-OH omeprazole in RLMs but did not change the affinity of the enzymes. The V_max and CL_int of RLMs from UC rats were 62% and 48% those of RLMs from normal rats, respectively. The hepatic CYP1A2 and CYP3A1 protein levels in UC rats were 42.6 and 45.2% lower than those in normal rats, respectively; however, the protein levels of CYP2D1 in the two groups were similar. The activity and expression of some hepatic CYP450 isoforms were decreased by UC, leading to changes in the pharmacokinetics of omeprazole.

Effect of X-ray irradiation on pharmacokinetics of irinotecan hydrochloride and expression of CES1 and CYP3A1 in rats

Concurrent chemoradiation with irinotecan hydrochloride (CPT-11) is accepted for cancer treatment. However, the effects of X-ray irradiation on chemotherapeutics in the plasma remain unclear. We evaluated the pharmacokinetics of CPT-11 in rats after exposure to X-ray irradiation and examined the changes of protein and mRNA expression of CES1 and CYP3A1. The X-ray irradiation with 1 Gy and 5 Gy was delivered to the whole body of rats. CPT-11 at 30 and 60 mg/kg, respectively, was intravenously infused 24 h after irradiation. CPT-11 was determined by RP-HPLC in plasma. ELISA and PCR were used to analyze the protein and mRNA expression of CES1 and CYP3A1, respectively. Compared with control rats, the X-ray irradiation decreased the AUC of CPT-11 (30 mg/kg) by 15.6% at 1 Gy and 39.0% at 5 Gy and increased the CL by 60.0% at 5 Gy. The X-ray irradiation could also decrease the AUC of CPT-11 (60 mg/kg) and increase the CL. In addition, the protein and mRNA expression of CES1 and CYP3A1 were increased significantly in rats after irradiation. This study found significant changes in the pharmacokinetics of CPT-11 in rats after exposure to X-ray irradiation, and they might be due to significant increases in the expressions of CYP3A1 and CES1. The pharmacokinetics of CPT-11 should be rechecked, and the optimal CPT-11 dose should be reevaluated during concurrent chemoradiation therapy.

Bromuconazole-induced hepatotoxicity is accompanied by upregulation of PXR/CYP3A1 and downregulation of CAR/CYP2B1 gene expression

Despite widespread use of bromuconazole as a pesticide for food crops and fruits, limited studies have been done to evaluate its toxic effects. Here, we evaluated the hepatotoxic effect of bromuconazole using classical toxicological (biochemical analysis and histopathological examination) and gene-based molecular methods. Male rats were treated either orally or topically with bromuconazole at doses equal to no observed adverse effect level (NOAEL) and 1/10 LD50 for 90 d. Bromuconazole increased activities of liver enzymes (ALT, AST, ALP, and ACP), and levels of bilirubin. It also induced hepatic oxidative stress as evidenced by significant decrease in the activities of superoxide dismutase (SOD), and significant increase in levels of malondialdehyde (MDA) in liver. In addition, bromuconazole caused an increase in liver weights and necrobiotic changes (vacuolation and hepatocellular hypertrophy). It also strongly induced the expression of PXR and its downstream target CYP3A1 gene as well as the activity of CYP3A1. However, it inhibited the expression of CAR and its downstream target CYP2B1 gene without significant changing in CYP2B1 activity. Overall, the oral route showed higher hepatotoxic effect and molecular changes than the dermal route and all changes were dose dependent. This is the first investigation to report that bromuconazole-induced liver oxidative damage is accompanied by upregulation of PXR/CYP3A1 and downregulation of CAR/CYP2B1.

Multiple effects of magnesium isoglycyrrhizinate on the disposition of docetaxel in docetaxel-induced liver injury

1. Magnesium isoglycyrrhizinate (MgIg) has been extensively used in treating liver injury which is the common adverse reaction of docetaxel (DOC). Due to the narrow therapeutic window, small changes in pharmacokinetic profiles can alter the toxicity and therapeutic efficacy of DOC significantly. The study aimed to explore the effects of MgIg on the disposition of DOC and the potential mechanism in DOC-induced liver injury. 2. Pharmacokinetics and tissues distribution behaviors showed that there was no significant difference between DOC group (DOCG) and MgIg + DOC group (MDOCG). The mRNA and protein levels of cytochrome P450 3A1 (CYP3A1) in liver, intestine, and kidney were significantly upregulated, and the P-glycoprotein (P-gp) was obviously downregulated in MDOCG when compared with DOCG. 3. Immunoglobulin M (IgM), CD₈⁺ were upregulated in DOCG; while in MDOCG, IgM, CD₈⁺ recovered to normal levels and complement C₃; CD₄⁺ were upregulated. 4. MgIg had no significant effects on the disposition of DOC in docetaxel-induced liver injury. Additional, potential drug-drug interaction may happen if MgIg co-administered with antitumor drugs which are the substrates of CYP3A4 or P-gp. Hepatoprotective mechanism of MgIg perhaps was through upregulation of C₃, CD₄⁺ and downregulation of IgM, CD₈⁺.

The activity, protein, and mRNA expression of CYP2E1 and CYP3A1 in rats after exposure to acute and chronic high altitude hypoxia

The effects of exposure to acute and chronic high altitude hypoxia on the activity and expression of CYP2E1 and CYP3A1 were examined in rats. Rats were divided into low altitude (LA, 400 m), acute moderate altitude hypoxia (AMH, 2800 m), chronic moderate altitude hypoxia (CMH, 2800 m), acute high altitude hypoxia (AHH, 4300 m), and chronic high altitude hypoxia groups (CHH, 4300 m). Probe drugs were administrated orally to all five groups. Then the serum concentration of probe drug and its metabolite was determined by RP-HPLC. The activity of CYP2E1 and CYP3A1 was evaluated using the ratio of the metabolite to chlorzoxazone and testosterone, respectively. ELISA and real-time PCR were used to analyze the protein and mRNA expression of CYP2E1 and CYP3A1 in liver microsomes, respectively. Chronic high altitude hypoxia caused significant decreases in the activity and protein and mRNA expression of rat CYP2E1 and CYP3A1 in vivo. Acute high altitude hypoxia was not found to change the activity, protein or mRNA expression of rat CYP2E1 or CYP3A1. This study showed significant changes in the activity and protein and mRNA expression of CYP2E1 or CYP3A1 in rats after exposure to chronic high altitude hypoxia.

Inhibitory action of Epilobium hirsutum extract and its constituent ellagic acid on drug-metabolizing enzymes

Epilobium hirsutum (EH) is a medicinal plant for treating various diseases. Despite its wide usage, there is no available information about its potential influences on drug metabolism. The present study was undertaken to determine the in vivo effects of EH on hepatic CYP2B, CYP2C, CYP2D, and CYP3A enzymes that are primarily involved in drug metabolism. Male Wistar rats were injected intraperitoneally with EH water extract (EHWE) and ellagic acid (EA) at a daily dose of 37.5 and 20 mg/kg, respectively, for 9 days and hepatic drug-metabolizing enzymes were assessed at activity, protein and mRNA levels. Erythromycin N-demethylase activity was inhibited by 53 and 21 % in EHWE- and EA-treated rats, respectively. Benzphetamine N-demethylase and 7-benzyloxyresorufin-O-debenzylase activities were decreased by 53 and 43 %, and 57 and 57 % in EHWE-and EA-treated rats, respectively. Moreover, protein levels of CYP2B1, CYP2C6, CYP2D2, and CYP3A1 also decreased by 55, 15, 33, and 82 % as a result of EHWE treatment of rats, respectively. Similarly, CYP2B1, CYP2C6, CYP2D2, and CYP3A1 protein levels decreased by 62, 63, 49, and 37 % with EA treatment, respectively. qRT-PCR analyses also showed that mRNA levels of these enzymes were significantly inhibited with bothEHWE and EA treatments. In conclusion, inhibition of drug clearances leading to drug toxicity because of the lowered activity and expression of drug-metabolizing enzymes might be observed in the people who used EH as complementary herbal remedy that might be contributed by its EA content.