Cytochrome P-450 Content Research Articles

Cadmium causes spleen toxicity in chickens by regulating mitochondrial unfolded protein response and nuclear receptors response

Cadmium (Cd) is a heavy metal that pollutes the environment and threatens human and animal health via the food chain. The spleen is one of the target organs affected by Cd toxicity. However, the mechanism of Cd toxicity is not fully understood. In this study, 80 chicks were allocated into 4 groups (n = 20) and exposed to different doses of CdCl2 (0 mg/kg, 35 mg/kg, 70 mg/kg and 140 mg/kg) for 90 d. The pathological changes in the spleen, mitochondrial dynamics-related factors, cytochrome P450 (CYP450) enzyme system contents, activities, transcription levels, nuclear receptors (NRs) response molecule levels, and mitochondrial unfolded protein-related factors were detected. The findings indicate that exposure to Cd significantly leads to spleen injury. In Cd groups, the total contents of CYP450 and cytochrome b5 (Cyt b5) increased, and the activities of the CYP450 enzyme system (APND, ERND, AH, and NCR) changed. The NRs response was induced, and the gene levels of AHR/CAR and corresponding CYP450 isoforms (CYP1B1, CYP1A5, CYP1A1, CYP2C18, CYP2D6 and CYP3A4) were found altered. The study found that Cd exposure altered the mRNA expression levels of mitochondrial dynamics-related factors, such as OPA1, Fis1, MFF, Mfn1, and Mfn2, breaking mitochondrial fusion and cleavage and ultimately leading to mitochondrial dysfunction. Changes were detected in the gene levels of several mitochondrial unfolded protein response (mtUPR)-related factors, namely (SIRT1, PGC-1α, NRF1, TFAM, SOD2, and HtrA2). Cd also altered the gene levels of mitochondrial function-related factors (VDAC1, Cyt-C, COA6, PRDX3, RAF and SIRT3). It is showed that Cd can initiate the NRs response, influence the homeostasis of the CPY450 enzyme system, trigger the mtUPR, impair mitochondrial function, and ultimately lead to Cd toxicity in the spleen of chickens.

UV filter benzophenone-2: Effects on zebrafish (Danio rerio) cytochrome P450

Benzophenone-2 (2,2′, 4,4′- Tetrahydroxybenzophenone; BP-2) is widely used as a sunscreen in Personal and Care Products (PCPs) for protection against ultraviolet (UV) radiation. The effects of BP-2 on random-sex adult zebrafish (Danio rerio) cytochrome P450 (CYP450) were studied. The main goal was to investigate the detoxification mechanisms underlying the adverse consequences of exposure to xenobiotic chemicals such as BP-2. Total protein content, CYP450 content, and erythromycin N-demethylase (ERND) activity were evaluated as indicators of protein CYP3A expression. Five sets of pooled random-sex adult zebrafish were exposed to 0.0, 0.1, 5.0, and 10.0 mg/L of BP-2 to evaluate their acute and chronic toxicity (4 and 15 days, respectively). ERND activity was significantly increased in the chronic toxicity group compared to that in the control group, whereas CYP450 remained unchanged. The results suggest a sufficiently fast catalytic process that does not alter the total CYP450 content. It implies a mediation of CYP450 3A induction by BP-2 and the pregnane X receptor ligand-binding domain (PXR LBD) interaction. Ligand-protein interactions were confirmed via in silico docking with AutoDock Vina. Further computational studies indicate BP-2 potential binding affinity for the Estrogen receptor alpha ligand binding domain (ERα LBD). These results suggest that CYPs effects may result in significant toxicity in the zebrafish. Our study highlights the importance of studying biomarkers in aquatic organisms to assess xenobiotic exposure and the potential toxicity of UV filters to humans.

Exploring the Mechanisms of Yuanhu Zhitong Oral Liquid for Primary Dysmenorrhea through Network Pharmacology, Molecular Docking, and Molecular Dynamics Simulation

Objective: Primary dysmenorrhea (PD) is a prevalent gynecological disorder. Yuanhu Zhitong oral liquid (YHZT) presents a promising alternative treatment for PD. However, the mechanisms underlying its efficacy remain unclear. This study aims to investigate the potential targets and mechanisms of action of YHZT in treating PD using network pharmacology, molecular docking, and molecular dynamics simulations. Methods: Potential compounds from YHZT were obtained from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP) and the Traditional Chinese Medicine Information Database (TCMID). The relevant targets of these compounds were identified using the similarity ensemble approach (SEA) and the Swiss Target Prediction database. PD-related targets were retrieved from the Genecards, DrugBank, and Disgenet databases. ClusterProfiler was utilized for Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. The compound-target-pathway (CTP) network was constructed to facilitate the identification of key compounds, core targets, and signaling pathways. Finally, molecular docking and molecular dynamics simulations were performed to evaluate the interactions between the targets and compounds. Results: A total of 153 putative compounds and 129 targets of YHZT were identified. Network topology analysis revealed eight core targets and six key compounds. The effects of YHZT were mediated by genes associated with hormone and steroid metabolism, as well as pathways involved in steroid hormone biosynthesis and cytochrome P450 enzymes. Docking results showed free-binding energies ranging from -6.06 to -10.85 kcal/mol, indicating strong binding affinity between the compounds and targets. Molecular dynamics simulation results further confirmed the stability of these interactions. Conclusion: This study demonstrates that YHZT treats PD by suppressing inflammatory reactions and modulating hormone and cytochrome P450 concentrations. Key compounds such as ferulic acid, (R)-canadine, (S)-canadine, canadine, and asristolone are implicated in this process. These findings offer insights into the mechanisms underlying the action of YHZT and provide a foundation for further research in this area.

Mode of action analysis for fluxapyroxad-induced rat liver tumour formation: evidence for activation of the constitutive androstane receptor and assessment of human relevance

The fungicide fluxapyroxad (BAS 700 F) has been shown to significantly increase the incidence of liver tumours in male Wistar rats at dietary levels of 1500 and 3000 ppm and in female rats at a dietary level of 3000 ppm via a non-genotoxic mechanism. In order to elucidate the mode of action (MOA) for fluxapyroxad-induced rat liver tumour formation a series of in vivo and in vitro investigative studies were undertaken. The treatment of male and female Wistar rats with diets containing 0 (control), 50, 250, 1500 and 3000 ppm fluxapyroxad for 1, 3, 7 and 14 days resulted in a dose-dependent increases in relative weight at 1500 and 3000 ppm from day 3 onwards in both sexes, with an increase in relative liver weight being also observed in male rats given 250 ppm fluxapyroxad for 14 days. Examination of liver sections revealed a centrilobular hepatocyte hypertrophy in some fluxapyroxad treated male and female rats. Hepatocyte replicative DNA synthesis (RDS) was significantly increased in male rats given 1500 and 3000 ppm fluxapyroxad for 3 and 7 days and in female rats given 50–3000 ppm fluxapyroxad for 7 days and 250–3000 ppm fluxapyroxad for 3 and 14 days; the maximal increases in RDS in both sexes being observed after 7 days treatment. The treatment of male and female Wistar rats with 250–3000 ppm fluxapyroxad for 14 days resulted in significant increases in hepatic microsomal total cytochrome P450 (CYP) content and CYP2B subfamily-dependent enzyme activities. Male Wistar rat hepatocytes were treated with control medium and medium containing 1–100 μM fluxapyroxad or 500 μM sodium phenobarbital (NaPB) for 4 days. Treatment with fluxapyroxad and NaPB increased CYP2B and CYP3A enzyme activities and mRNA levels but had little effect on markers of CYP1A and CYP4A subfamily enzymes and of the peroxisomal fatty acid β-oxidation cycle. Hepatocyte RDS was significantly increased by treatment with fluxapyroxad, NaPB and 25 ng/ml epidermal growth factor (EGF). The treatment of hepatocytes from two male human donors with 1–100 μM fluxapyroxad or 500 μM NaPB for 4 days resulted in some increases in CYP2B and CYP3A enzyme activities and CYP mRNA levels but had no effect on hepatocyte RDS, whereas treatment with EGF resulted in significant increase in RDS in both human hepatocyte preparations. Hepatocytes from male Sprague-Dawley wild type (WT) and constitutive androstane receptor (CAR) knockout (CAR KO) rats were treated with control medium and medium containing 1–16 μM fluxapyroxad or 500 μM NaPB for 4 days. While both fluxapyroxad and NaPB increased CYP2B enzyme activities and mRNA levels in WT hepatocytes, only minor effects were observed in CAR KO rat hepatocytes. Treatment with both fluxapyroxad and NaPB only increased RDS in WT and not in CAR KO rat hepatocytes, whereas treatment with EGF increased RDS in both WT and CAR KO rat hepatocytes. In conclusion, a series of in vivo and in vitro investigative studies have demonstrated that fluxapyroxad is a CAR activator in rat liver, with similar properties to the prototypical CAR activator phenobarbital. A robust MOA for fluxapyroxad-induced rat liver tumour formation has been established. Based on the lack of effect of fluxapyroxad on RDS in human hepatocytes, it is considered that the MOA for fluxapyroxad-induced liver tumour formation is qualitatively not plausible for humans.

Transformation of 6:6 PFPiA in the gut of Xenopus laevis: Synergistic effects of CYP450 enzymes and gut microflora

As a frequently detected per- and polyfluoroalkyl substance in the environment, 6:6 perfluoroalkylhypophosphinic acid (6:6 PFPiA) is vulnerable to transformation in the liver of organisms, but the transformation in gut is still unclear. This study investigates the molecular mechanisms of 6:6 PFPiA transformation in the gut of Xenopus laevis upon a 28-day exposure in water. Before Day 16, a notable correlation (p = 0.03) was observed between the transformation product (PFHxPA) and cytochrome P450 (CYP450) enzyme concentration in gut. This suggests that CYP450 enzymes played an important role in the transformation of 6:6 PFPiA in the gut, which was verified by an in vitro incubation with gut tissues, and supported by the molecular docking results of 6:6 PFPiA binding with CYP450 enzymes. From the day 16, the CYP450 concentration in gut decreased by 31.3 % due to the damage caused by 6:6 PFPiA, leading to a decrease in the transformation capacity in gut, but the transformation rate was stronger than in liver. This was in contrast with the in vitro experiment, where transformation was stronger in liver. In the mean time, the abundance of Bacteroidota in gut increased, which released hydrolytic enzyme and then could participate in the transformation as well. This study reveals the potential of the gut in metabolizing environmental pollutants, and provides profound insights into the potential health risks caused by 6:6 PFPiA in organisms.

Comparison of the CYP3A Selective Inhibitors CYP3cide, Clobetasol, and Azamulin for Their Potential to Distinguish CYP3A7 Activity in the Presence of CYP3A4/5.

The CYP3A7 enzyme accounts for ∼50% of the total cytochrome P450 (P450) content in fetal and neonatal livers and is the predominant P450 involved in neonatal xenobiotic metabolism. Additionally, it is a key player in healthy birth outcomes through the oxidation of dehydroepiandrosterone (DHEA) and DHEA-sulfate. The amount of the other hepatic CYP3A isoforms, CYP3A4 and CYP3A5, expressed in neonates is low but highly variable, and therefore the activity of individual CYP3A isoforms is difficult to differentiate due to their functional similarities. Consequently, a better understanding of the contribution of CYP3A7 to drug metabolism is essential to identify the risk that drugs may pose to neonates and developing infants. To distinguish CYP3A7 activity from CYP3A4/5, we sought to further characterize the selectivity of the specific CYP3A inhibitors CYP3cide, clobetasol, and azamulin. We used three substrate probes, dibenzylfluorescein, luciferin-PPXE, and midazolam, to determine the IC50 and metabolism-dependent inhibition (MDI) properties of the CYP3A inhibitors. Probe selection had a significant effect on the IC50 values and P450 inactivation across all inhibitory compounds and enzymes. CYP3cide and azamulin were both identified as MDIs and were most specific for CYP3A4. Contrary to previous reports, we found that clobetasol propionate (CP) was not an MDI of CYP3A5 but was more selective for CYP3A5 over CYP3A4/7. We further investigated CYP3cide and CP's ability to differentiate CYP3A7 activity in an equal mixture of recombinant CYP3A4, CYP3A5, and CYP3A7, and our results provide confidence of CYP3cide's and CP's ability to distinguish CYP3A7 activity in the presence of the other CYP3A isoforms. SIGNIFICANCE STATEMENT: These findings provide valuable insight regarding in vitro testing conditions to investigate the metabolism of new drug candidates and help determine drug safety in neonates. The results presented here also clearly demonstrate the effect that probe selection may have on CYP3A cytochrome P450 inhibition studies.

Synthesis, Characterization, and Ecotoxicology Assessment of Zinc Oxide Nanoparticles by In Vivo Models

The widespread use of zinc oxide nanoparticles (ZnO NPs) in multiple applications has increased the importance of safety considerations. ZnO NPs were synthesized, characterized, and evaluated for toxicity in Artemia salina and zebrafish (Danio rerio). NPs were characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), and ultraviolet-visible (UV-Vis) spectroscopy. The hydrodynamic size and stability of the ZnO NP surface were examined using a Zetasizer. Characterization techniques confirmed the ZnO wurtzite structure with a particle size of 32.2 ± 5.2 nm. Synthesized ZnO NPs were evaluated for acute toxicity in Artemia salina using the Probit and Reed and Muench methods to assess for lethal concentration at 50% (LC50). The LC50 was 86.95 ± 0.21 μg/mL in Artemia salina. Physical malformations were observed after 96 h at 50 μg/mL of exposure. The total protein and cytochrome P450 contents were determined. Further analysis was performed to assess the bioaccumulation capacity of zebrafish (Danio rerio) using ICP-OES. ZnO NP content in adult zebrafish was greater in the gastrointestinal tract than in the other tissues under study. The present analysis of ZnO NPs supports the use of Artemia salina and adult zebrafish as relevant models for assessing toxicity and bioaccumulation while considering absorption quantities.

Unravelling drug-drug interactions in pigs: Induction of hepatic cytochrome P450 1A (CYP1A) metabolism after the in-feed medication with the anthelmintic fenbendazole

The anthelmintic fenbendazole (FBZ) undergoes hepatic S‑oxygenation by monooxygenases belonging to the cytochrome P450 (CYP) and flavin-monooxygenase (FMO) families. The in-feed medication with FBZ induced CYP1A-dependent metabolism in pig liver. This fact may alter the metabolism of the anthelmintic itself, and of CYP1A substrates like aflatoxin B1 (AFB1). This work evaluated the effect of the in-feed administration of FBZ on CYP1A-dependent metabolism, on its own pattern of hepatic S‑oxygenation, and on the metabolism of AFB1. Landrace piglets remained untreated (n = 5) or received a pre-mix of FBZ (n = 6) in feed for 9 days. Pigs were slaughtered for preparation of liver microsomes used for: CYP content determination; monitoring the CYP1A-dependent enzyme activities, 7-ethoxyresorufin O-deethylase (EROD) and 7-methoxyresorufin O-demethylase (MROD); measurement of FBZ (50 μM) S‑oxygenation, and AFB1 (16 nM) disappearance from the incubation medium. In microsomes of FBZ-treated animals, EROD and MROD increased 19-fold (p = 0.002) and 14-fold (p = 0.003), respectively. An enhanced (3-fold, p = 0.004) participation of the CYP pathway in FBZ S‑oxygenation was observed in the liver of piglets treated with the anthelmintic (210 ± 69 pmol/min.nmol CYP) compared to untreated animals (68 ± 34 pmol/min.nmol CYP). AFB1 metabolism was 93% higher (p = 0.009) in the liver of FBZ-treated compared to untreated pigs. Positive and significant (p < 0.05) correlations were observed between CYP1A-dependent enzyme activities and FBZ or AFB1 metabolism. The sustained administration of FBZ caused an auto-induction of the CYP1A-dependent S‑oxygenation of this anthelmintic. The CYP1A induction triggered by the anthelmintic could amplify the production of AFB1 metabolites in pig liver, including the hepatotoxic AFB1-derived epoxide.++

A assembled plate column bioreactor for adherent cell culture

The ideal bioreactor should be highly efficient, cost-effective and able to promote cells adhesion growth. In this study, we constructed a plate-tower bioreactor with S-loop in each layer based on multilayer plate bioreactor and plate column theory. Human hepatocellular carcinomas(HepG2) and human normal liver cell L02 (L02) cells were employed evaluation of bioreactor performance. The results show that cells were able to adhere to the plates and the density reached to 1～1.2 × 105/cm2. When circulating flow rate of the reactor is 8 ml/min and the oxygen supply concentration is 40 %, the sufficient material and gas exchange in bioreactor, the amount of albumin, urea and cytochrome P450(CYP450) content in the hyperoxia group were 3.31, 2.58 and 2.6 times higher than that of the control group, there was no obvious cell damage. This condition up the regulation of genes in more metabolic pathways and improved the metabolic capacity of hepatocytes. The single-layer area and the number of bioreactors can be flexibly adjusted, and the manufacturing cost of single-layer is close to that of ordinary plastic cell culture dishes. Either batch or continuous mode can be used in the bioreactor. In view of the above characteristics, the bioreactor is more conducive to practical application.

Role of Cytochrome p450 in Clopidogrel Resistance in Indonesian Stroke Patients

BACKGROUND: Stroke is the second leading cause of death in the world. Clopidogrel is one of the recommended therapies for it. Disturbances in the metabolic stages of clopidogrel, such as dysregulation of cytochrome p450 (CYP450) and cytochrome P450 2C19 (CYP2C19), can cause unresponsiveness or resistance. However, studies on clopidogrel resistance related to CYP450 and CYP2C19 in Indonesia are limited. METHODS: This cross-sectional study was conducted in two hospitals over a 1-year period. All patients had a minimum of one episode of ischemic stroke. Data on demographics, clopidogrel resistance, CYP450 concentration, and CYP2C19 polymorphism were collected. In total, 112 participants were enrolled in this study. RESULTS: We found that the incidence of clopidogrel resistance was 14.3% and the bleeding risk was high (40.3 %). The number of mutations in the CYP2C19 allele *17 was 96.0%. We also found that sex, hemoglobin, and CYP450 were significantly correlated with clopidogrel resistance, and with hemoglobin and CYP450 as independent factors. Fasting blood glucose and CYP2C19 allele *3 were independent factors for CYP450. CONCLUSION: The incidence of clopidogrel resistance in the Indonesian population is low; therefore, it is not an urgent issue. An important issue in this population is the high risk for bleeding. Patient treatment should be adjusted by considering this risk.

Toxicities of polystyrene microplastics (MPs) and hexabromocyclododecane (HBCD), alone or in combination, to the hepatopancreas of the whiteleg shrimp, Litopenaeus vannamei

The hepatopancreas is one of the largest organs playing crucial roles in metabolism and detoxification in crustacean invertebrates. Although toxicities have been increasingly documented for the two ubiquitous pollutants, hexabromocyclododecane (HBCD) and microplastics (MPs), in model animals, little is known about their impacts on the hepatopancreas of crustaceans. To fill this knowledge gap, the effects of MPs and HBCD, alone or in combination, on the hepatopancreas were evaluated in a commercially important crustacean species (the whiteleg shrimp) by histological observation as well as quantification of hepatic lesion-, metabolism-, and detoxification-related parameters. In addition, to reveal potential mechanisms underlying the hepatoxicity observed, the accumulation of HBCD in the shrimp and the status of oxidative stress were also investigated. Our results demonstrated that exposure of the whiteleg shrimp to MPs and HBCD for 4 weeks resulted in evident histological injury in the hepatopancreas and marked elevation in hepatic lesion markers (alanine aminotransferase and aspartate aminotransferase) in the hemolymph. Moreover, both metabolism (activity of phosphofructokinase, contents of lactic acid and adenosine triphosphate, and expression of metabolism-related genes) and detoxification (contents of cytochrome P450, UDP-glucuronosyltransferase, and glutathione, activity of glutathione S-transferase, and expression of detoxification-related genes) were found to be disrupted by the pollutants tested. In addition, exposure to MPs and HBCD also led to alterations in the contents and/or activities of antioxidant enzymes and resulted in oxidative damage to the hepatopancreas (indicated by marked elevation in malondialdehyde content). Furthermore, a significant amount of HBCD accumulated in shrimp treated with HBCD-containing seawater. The data also illustrated that HBCD-MP coexposure was more toxic than single exposure to these pollutants. These findings suggest that MPs and HBCD may exert hepatotoxic impacts on whiteleg shrimp by accumulating in vivo and inducing oxidative stress, which could pose a severe threat to the health of this important crustacean species.

Establishing allometric relationships between microsomal protein and cytochrome P450 content with body weight in vertebrate species

Data from in vitro studies are routinely used to estimate in vivo hepatic clearance of chemicals and this information is needed to parameterise physiologically based kinetic models. Such clearance data can be obtained from laboratory experiments using liver microsomes, hepatocytes, precision-cut liver slices or recombinant enzymes. Irrespective of the selected test system, scaling factors are required to convert the in vitro measured intrinsic clearance to a whole liver intrinsic clearance. Scaling factors such as the hepatic microsomal protein per gram of liver and/or the amount of cytochrome P450 per hepatocyte provide a means to calculate the whole liver intrinsic clearance. Here, a database from the peer-reviewed literature has been developed and provides quantitative metrics on microsomal protein (MP) and cytochrome P450 contents in vertebrate orders namely amphibians, mammals, birds, fish and reptiles. This database allows to address allometric relationships between body weight and MP content, and body weight and cytochrome P450 content. A total of 85 and 74 vertebrate species were included to assess the relationships between log10 body weight versus log10 MP, and between log10 body weight and log10 cytochrome P450 content, respectively. The resulting slopes range from 0.76 to 1.45 in a range of vertebrate species. Such data-driven allometric relationships can be used to estimate the MP content necessary for in vitro to in vivo extrapolation of in vitro clearance data. Future work includes applications of these relationships for different vertebrate taxa using quantitative in vitro to in vivo extrapolation models coupled to physiologically based kinetic models using chemicals of relevance as case studies including pesticides, contaminants and feed additives.

Функціональний стан печінки за одноразового перорального впливу на організм деяких метильних похідних n-оксид піридину

RESUME. Pesticides occupy one of the priority places among environmental pollutants. The hepatobiliary system disorder is a characteristic of most pesticides. The hepatotoxic effect of synthetic plant growth regulators (PGRs) based on pyridine N-oxide isn’t explored enough. The hepatotoxic effect PGR nature finding is an important aspect of preventive toxicology. Aim. To study the effect of some pyridine-N-oxide methyl derivatives on the liver functional state under a single oral dosage into the body. Materials and Methods. For the research were used PGRs – 2.6-dimethylpyridine-N-oxide (Ivin), 99.9 % and complex 2.6- dimethylpyridine-N-oxide with succinic acid (Poteitin), 99.9 %. During the experiment which was carried out on male Wistar Han rats, it was a single oral administration of aqueous solution form of test substances: Ivin in doses of 650 and 13 mg/kg and Poteitin in doses 1150 and 23 mg/kg. The activity of the alanineaminotransferase (ALT), aspartateaminotransferase (AST), alkaline phosphatase (ALP), the content of total proteins, glucose, triglycerides, cholesterol, urea and creatinine in the blood serum were determined on the 1st, 3rd, and 7th day using “Filisit- Diagnostics” reagent kit. EPR signals (g-2.25; g-2.14; g-2.05; g-2.03; g-2.00; g-1.97; g-1.94) were determined in liver tissue on the radio spectrophotometer “Varian E-109” (USA) at a temperature of 77 K. The results. Ivin at a dose of 13 mg/kg in particular study periods significantly increased the content of urea and glucose. At a dose of 650 mg/kg, the activity of AST, the content of urea, creatinine, and glucose significantly increased, and the activity of ALP decreased. Poteitin in a dose of 23 mg/kg in particular study times significantly increased the content of urea and creatinine, and the activity of ALP in the blood serum. At a dose of 1150 mg/kg, a significant decrease in the activity of ALP, and an increase in the content of urea, creatinine and glucose in the blood serum were revealed. The majority of liver EPR signals were reduced due to the influence of Ivin and Poteitin in both studied doses in different terms. Ivin at a dose of 13 mg/kg decreased the content of Mo7+-containing proteins and free radicals (FR) on 1st and 7th days respectively. At a dose of 650 mg/kg increased the content of iron-sulfur proteins (ISP) in 1stday of experiment and there was a decrease in the content of cytochrome P-450 (CytP-450), nitrosyl complexes, ISP and free radicals (FR) in 7 days. Poteitin at a dose of 23 mg/kg decreased the content of cyt-P-450, FR, ISP, and Mo7+–containing proteins, and increased the content of Cu2+-containing proteins. At a dose of 1150 mg/kg, there was a decrease in the content of cyt-P-450, BP, and ISP (for 1st and 3th days) and their increase for 7 days. Conclusions. With acute oral exposure, Ivin and Poteitin show a weak hepatotropic effect, characterized by a hyperglycemia, a slight decrease in the activity of alkaline phosphatase and an increase in urea and creatinine levels in the blood serum. Hyperglycemia can be associated with a stressogenic reaction to a chemical factor. This may indicate a carbohydrate metabolism disorders and various pathological conditions with long-term exposure to the studied substances. Intensification of the protein degradation and the accumulation of urea and creatinine in the blood serum can lead to a disorder of the filtering and excretory functions of the kidneys, which requires further research and clarification. Ivin and Poteitin reduce the EPR spectra of rat liver – cyt-P-450, free radicals, iron-sulfur proteins, nitrosyl complexes of non-heme iron, which indicates a decrease in the activity of the monooxygenase system, inhibition of oxidation processes, the formation disruption of iron-sulfur complexes and a decrease in the labile nitrosyl complex formation. A decrease in the content of Mo7+-containing proteins and an increase in the content of Cu2+-containing proteins may be associated with the activation of antiradical processes in the liver of rats. Key Words: plant growth regulators, Ivin, Poteitin, hepatotoxic effect, liver EPR spectra.

Content of cytochrome P-450 in microsomal fractions of the liver of pregnant rats and their embryos

This article presents a comprehensive examination of the impact of the pesticide “dropp” on the lipid peroxidation (LPO) of microsome membranes and the levels of cytochrome P-450 enzyme within microsomal fractions of pregnant rats and their developing embryos. The study delves into the intricate biochemical responses within these biological systems following exposure to the pesticide. The research uncovers a significant intensification of NADP.Nand ascorbate-dependent lipid peroxidation in the liver microsomes of both pregnant rats and their embryos upon exposure to the “dropp” pesticide. This heightened lipid peroxidation is particularly notable on the 3rd day of pregnancy, accompanied by an elevated concentration of malondialdehyde (MDA), a marker of oxidative stress. Moreover, the study reveals a noteworthy impact of “dropp” on the content of cytochrome P-450 enzyme within the microsomal fraction of the liver in pregnant rats. This enzyme, which plays a vital role in various metabolic processes, experiences a reduction in concentration upon pesticide exposure. The effect is most pronounced on the 3rd and 19th days of pregnancy, highlighting specific time windows of vulnerability. Collectively, these findings provide a nuanced understanding of the biochemical repercussions of “dropp” pesticide exposure on the microsomal membranes and enzyme dynamics within pregnant rats and their developing embryos.

Cross-resistance and biochemical resistance mechanisms of avermectin resistant population of Dendrolimus punctatus.

To identify the resistance risk and the resistance mechanism of avermectin against Dendrolimus punctatus, we examined the cross-resistance of avermectin resistance population (AV) to multiple tested insecticides and the synergism of piperonyl butoxide (PBO), triphenyl phosphate (TPP) and diethyl maleate (DEM) to AV, Qin-ling Jieguanting (JGT) and susceptible (S) popultions, by leaf dipping method. The activities of carboxylesterase (CarE), glutathione S-transferases (GST) and mixed-functional oxidases (MFOs) in AV, JGT and S populations of D. punctatus was measured with spectrophotometry. The results showed that the AV population of D. punctatus had medium level of cross-resistance to emamectin benzoate (resistance ratio, RR50=25.0), chlorpyrifos (RR50=19.0), and cyhalothrin (RR50=15.4), and low level of cross-resistance to chlorfenapyr (RR50=8.1), but no cross-resistance to spinetoram, spinosad and chlorantraniliprole. Both PBO and TPP had significant synergism of avermectin to AV, JGT, and S populations, while DEM had no synergism to all the three populations. Compared with the S population, the AV population had higher content of MFOs cytochromes P450(3.5-fold) and b5(3.1-fold) and the activities of O-demethylase (4.1-fold) and CarE (2.2-fold). There was no significant difference in the activities of GST between AV and S populations. The increasing mixed-functional oxidases and CarE played an important role in the resistance of D. punctatus to avermectin. Spinetoram, spinosad, chlorantraniliprole, and avermectin were recommended to control D. punctatus.

The effect of some pesticides on lipid peroxidation and on the content of cytochrome p-450 of mitochondrial membranes and liver microsomes of pregnant rats and their embryos

The article presents data obtained in experimental studies on the effect of pesticides - butylcaptax and droppa on lipid peroxidation of mitochondrial membranes and microsomes of liver cells of pregnant rats and their embryos. It has been shown that inoculation with pesticides intensifies NADP.H- and ascorbate-dependent LPO both in mitochondria and in liver microsomes of pregnant rats and their embryos. The level of MDA is higher in case of poisoning with butylcaptax on the 3rd day of pregnancy. A decrease in the content of the microsomal enzyme P-450 in the microsomal fraction of the liver of pregnant rats was also found with the introduction of butylcaptax and dropp. This decrease is more pronounced on butylcaptax poisoning on the 3rd and 19th days of pregnancy.

Atrazine exposure induces necroptosis through the P450/ROS pathway and causes inflammation in the gill of common carp (Cyprinus carpioL.)

Atrazine (ATR) is used worldwide and has been confirmed be hazardous materials that harmful to the health of organisms. Since ATR was more persistent in the water, the specific damage caused by ATR to aquatic organisms should be concern. The role of P450/ROS has been proposed in many pathomechanisms. To explore whether P450/ROS mediated necroptosis and promote inflammatory response caused by ATR exposure, 120 common carp (Cyprinus carpio L.) were randomly divided into four groups which were exposed to 0 μg/L, 4 μg/L, 40 μg/L and 400 μg/L ATR respectively. The residual levels of ATR and its metabolites increased, signs of necrosis and inflammation were found in the gills of the ATR-treatment groups. The levels of ROS and cytochrome P450 content were increased, and P450 enzymes were activated. The expression levels of the core components of necroptosis (RIPK1, RIPK3 and MLKL) increased. Moreover, gene expression of inflammatory factors (TNF-α, NF-κB, iNOS, COX-2, IL-1β and PTGE) increased significantly in the ATR-spiked group. Our results suggested that ATR exposure triggered necroptosis through the P450/ROS pathway and causes inflammation of common carp gill. This study provides valuable clue about the mechanism by which ATR causes injury to common carp gill.

Antifeedant Mechanism of Dodonaea viscosa Saponin A Isolated from the Seeds of Dodonaea viscosa.

Dodonaea viscosa is a medicinal plant which has been used to treat various diseases in humans. However, the anti-insect activity of extracts from D. viscosa has not been evaluated. Here, we found that the total saponins from D. viscosa (TSDV) had strong antifeedant and growth inhibition activities against 4th-instar larvae of Spodoptera litura. The median antifeeding concentration (AFC50) value of TSDV on larvae was 1621.81 μg/mL. TSDV affected the detoxification enzyme system of the larvae and also exerted antifeedant activity possibly through targeting the γ-aminobutyric acid (GABA) system. The AFC50 concentration, the carboxylesterase activity, glutathione S-transferases activity, and cytochrome P450 content increased to 258%, 205%, and 215%, respectively, and likewise the glutamate decarboxylase activity and GABA content to 195% and 230%, respectively, in larvae which fed on TSDV. However, D. viscosa saponin A (DVSA) showed better antifeedant activity and growth inhibition activity in larvae, compared to TSDV. DVSA also exerted their antifeedant activity possibly through targeting the GABA system and subsequently affected the detoxification enzyme system. Further, DVSA directly affected the medial sensillum and the lateral sensillum of the 4th-instar larvae. Stimulation of Spodoptera litura. with DVSA elicited clear, consistent, and robust excitatory responses in a single taste cell.

Effects and mechanism of ultrasound treatment on Chironomus kiiensis eggs.

Chironomids are abundant insects in freshwater ecosystems and lay in still or slow-moving water. The walls of sedimentation tanks in drinking water treatment plants (DWTP) provide such laying habitat, which can lead to larval outbreaks in plant effluent. While chironomid larvae are often associated with poor hygiene, effective methods to control outbreaks are needed. Here, we assessed the effect of ultrasound treatment on Chironomus kiiensis' eggs. The mortality rate of eggs was examined after ultrasound treatment, and the protein content (heat shock protein 70 and hemoglobin) and enzymatic activities of acetylcholinesterase, cytochrome P450, and glutathione S-transferases involved in the ultrasound-induced stress response were analyzed before and after treatment. COMSOL software was also used to examine the characteristics of the ultrasonic field, including frequency, power, exposure distance, and time. Higher egg mortality was observed at lower frequencies. At 28kHz, 450W, 15-mm exposure distance, and 75-s exposure time, 72.4% of eggs showed apoptosis after exposure. At higher frequencies (68kHz), mortality decreased to 50.9%. Exposure time and distance also significantly affected egg mortality. From the geometric models, it could be seen that C. kiiensis' eggs sustained much greater acoustic pressure (2379Pa) with 28-kHz exposure than that with 68-kHz exposure (422Pa); however, the propagation distance was greater at the higher frequency. The hydraulic shear force effect of the ultrasonic radiation appeared to be the primary factor in egg mortality. We expected that array of ultrasonic transducers embedded in the walls of water treatment plants could be effective in killing Chironomus' eggs and highlight the potential for ultrasound as an effective treatment for the prevention of Chironomus outbreaks in treatment plant effluents.

Utilization of CYP3A‐Specific Inhibitors to Study Cytochrome P450 CYP3A7 Activity in Neonatal Human Liver Microsomes

CYP3A7 is a member of the cytochrome P450 (CYP) 3A enzyme sub‐family that accounts for ~50% of the total CYP content in neonate and fetal livers. The amount of other CYP3A enzymes, CYP3A4 and CYP3A5, expressed in neonates is low but highly variable, and therefore, the activity of individual enzyme isoforms is difficult to differentiate. Recent studies report that CYP3cide, clobetasol propionate, and azamulin are specific inhibitors for CYP3A4, CYP3A5, and CYP3A4/5, respectively. However, the inhibitory effects towards CYP3A7 were not investigated for the latter two compounds, and the use of these compounds to study CYP3A7 activity has not been reported/investigated. Thus, we sought to characterize these compounds further and utilize them to isolate and study the activity of CYP3A7 in neonatal human liver microsomes. We have examined three substrate probes—dibenzylfluorescein, luciferin‐PPXE, and midazolam—to determine the IC50 values and mechanism‐based inactivation parameters (Ki, Kinact) of the purported isoform specific inhibitors. We discovered that azamulin was unable to selectively inhibit any of the CYP3As, but CYP3cide and clobetasol propionate exhibited IC50values for CYP3A4 and CYP3A5 two to three orders of magnitude lower than CYP3A7. CYP3cide and clobetasol propionate were further tested in mixtures of CYP3A4, CYP3A5, and CYP3A7 to mimic the neonatal human liver microsome environment and ascertain their effectiveness in isolating CYP3A7 activity. We were able to inhibit CYP3A4 without disturbing CYP3A7 activity using CYP3cide at concentrations below 5 μM. The majority of CYP3A5 activity was inhibited using low clobetasol propionate concentrations, but using higher concentrations also inhibited CYP3A7 activity due to its lower selectivity. These findings provide valuable insight regarding testing conditions to investigate the metabolism of new drug candidates and help determine drug safety in neonates.