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The 7-ethoxyresorufin-O-deethylase (EROD) activity was first time characterized in the neotropical fish Cnesterodon decemmaculatus as a biomarker for assessing environmental health in aquatic ecosystems of the Rio de la Plata Basin impacted by organic pollutants agonist of the aryl-hydrocarbon receptor (AhR). Both laboratory and field studies were conducted. Laboratory experiments were run using ß-naphthoflavone (BNF) as an AhR agonist model. A clear concentration-response relationship was found between 1 and 100 µg/L, with a NOEC and LOEC of 1 and 10 µg/L. A fast time-dependent response was observed with a significant induction after 24 h and a plateau from 24 to 48 h up to 264 h of exposure. Differences in basal activity were found between juveniles, females, and males, but induction levels were similar. Both basal activities and induction levels were distinct in the whole body, liver, gill, muscle, brain, and embryos. Fold-change inductions in the respective tissues were: 20, 114, 3, 5, 1, and 14. Maternal transfer and early cyp1a activation were unveiled by embryonic induction. Clear differences in EROD activity were found among juveniles collected in hydrocarbon-polluted streams, beside the La Plata Petrochemical hub, and a reference stream. Similar EROD activities were observed in laboratory and feral fish, usually with values below or above 1,000 pmol/min x mg protein for unexposed or exposed organisms. The study contributes with original information about EROD activity in C. decemmaculatus that encourages the use of both the response as a robust biomarker of exposure and the species as a good sentinel organism to be included in surveillant programs for assessing aquatic pollution by AhR agonist chemicals within the Rio de la Plata Basin within the One Health paradigm.

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Contamination of aquatic environments has been steadily increasing due to human activities. The Pacific oyster Crassostrea gigas has been used as a key species in studies assessing the impacts of contaminants on human health and the aquatic biome. In this context, cytochrome P450 (CYPs) play a crucial role in xenobiotic metabolism. In vertebrates many of these CYPs are regulated by nuclear receptors (NRs) and little is known about the NRs role in C. gigas. Particularly, the CgNR5A represents a homologue of SF1 and LRH-1 found in vertebrates. Members of this group can regulate genes of CYPs involved in lipid/steroid metabolism, with their activity regulated by other NR, called as DAX-1, generating a NR complex on DNA response elements (REs). As C. gigas does not exhibit steroid biosynthesis pathways, CgNR5A may play other physiological roles. To clarify this issue, we conducted an in silico investigation of the interaction between CgNR5A and DNA to identify potential C. gigas CYP target genes. Using molecular docking and dynamics simulations of the CgNR5A on DNA molecules, we identified a monomeric interaction with extended REs. This RE was found in the promoter region of 30 CYP genes and also the NR CgDAX. When the upstream regulatory region was analyzed, CYP2C39, CYP3A11, CYP4C21, CYP7A1, CYP17A1, and CYP27C1 were mapped as the main genes regulated by CgNR5A. These identified CYPs belong to families known for their involvement in xenobiotic and lipid/steroid metabolism. Furthermore, we reconstructed a trimeric complex, previously proposed for vertebrates, with CgNR5A:CgDAX and subjected it to molecular dynamics simulations analysis. Heterotrimeric complex remained stable during the simulations, suggesting that CgDAX may modulate CgNR5A transcriptional activity. This study provides insights into the potential physiological processes involving these NRs in the regulation of CYPs associated with xenobiotic and steroid/lipid metabolism.

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The enzyme NADPH-cytochrome P450 reductase (CPR) plays a central role in cytochromes P450 activity. Gene expression analysis of cytochromes P450 and CPR in deltamethrin-resistant and susceptible populations revealed that P450s genes are involved in the development of insecticide resistance in Triatoma infestans. To clarify the role of cytochromes P450 in insecticide resistance, it was proposed to investigate the effect of CPR gene silencing by RNA interference (RNAi) in a pyrethroid resistant population of T. infestans. Silencing of the CPR gene showed a significant increase in susceptibility to deltamethrin in the population analysed. This result support the hypothesis that the metabolic process of detoxification mediated by cytochromes P450 contributes to the decreased deltamethrin susceptibility observed in the resistant strain of T. infestans.

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Primaquine (PQ) is the main drug used to eliminate dormant liver stages and prevent relapses in Plasmodium vivax malaria. It also has an effect on the gametocytes of Plasmodium falciparum; however, it is unclear to what extent PQ affects P. vivax gametocytes. PQ metabolism involves multiple enzymes, including the highly polymorphic CYP2D6 and the cytochrome P450 reductase (CPR). Since genetic variability can impact drug metabolism, we conducted an evaluation of the effect of CYP2D6 and CPR variants on PQ gametocytocidal activity in 100 subjects with P. vivax malaria. To determine gametocyte density, we measured the levels of pvs25 transcripts in samples taken before treatment (D0) and 72 hours after treatment (D3). Generalized estimating equations (GEEs) were used to examine the effects of enzyme variants on gametocyte densities, adjusting for potential confounding factors. Linear regression models were adjusted to explore the predictors of PQ blood levels measured on D3. Individuals with the CPR mutation showed a smaller decrease in gametocyte transcript levels on D3 compared to those without the mutation (P = 0.02, by GEE). Consistent with this, higher PQ blood levels on D3 were associated with a lower reduction in pvs25 transcripts. Based on our findings, the CPR variant plays a role in the persistence of gametocyte density in P. vivax malaria. Conceptually, our work points to pharmacogenetics as a non-negligible factor to define potential host reservoirs with the propensity to contribute to transmission in the first days of CQ-PQ treatment, particularly in settings and seasons of high Anopheles human-biting rates.

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ETHNOPHARMACOLOGICAL RELEVANCE: Monteverdia ilicifolia (Maytenus ilicifolia, Celastraceae), known as "espinheira-santa", has been widely used in Brazil to manage mainly gastrointestinal diseases. This species has been listed in the Brazilian Pharmacopeia and in the National List of Essential Medicines (RENAME). Considering that clinical studies about M. ilicifolia are rare, our group has been performing a broader project designed to evaluate the efficacy of M. ilicifolia capsules in a clinical trial, for this reason, approaches to provide safety to those patients are relevant. AIM OF THE STUDY: We aimed to investigate the potential pharmacokinetic interaction and hepatotoxicity and intestinal toxicity of an aqueous extract of M. ilicifolia and its main phytocompounds, catequin, epicatequin, and quercetin. METHODS AND MATERIALS: Slices of liver and intestine of Wistar rats were incubated with different concentrations of M. ilicifolia extract or isolated compounds (catechin, epicatechin and quercetin). Commercial kits were used to evaluate enzyme activities of CYP2D6 and CYP3A4 isoforms, as well as cell viability (MTT) assay and intracellular enzymes leakage, specifically lactate dehydrogenase (LDH), alkaline phosphatase (AP), aspartate aminotransferase (AST), alanine aminotransferase (ALT) were studied. RESULTS: Incubation with M. ilicifolia extract, catechin, epicatechin and quercetin did not affect significantly any evaluated parameter in intestines. The intracellular enzymes leakages, CYP2D6, LDH and AST, were increased with M. ilicifolia extract and quercetin in liver slices. CONCLUSIONS: Our in vitro findings highlighted, for the first time, the potential hepatotoxicity induced by an aqueous extract of M. ilicifolia, consequently this species and its products should be avoided in liver diseases, supporting that studies of safety must be performed including in the context of traditional medicinal plants.

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PURPOSE: To describe our experiences implementing and iterating CYP2C19 genotype-guided clopidogrel pharmacogenetic clinical decision support (CDS) tools over time in the setting of a large health system-wide, preemptive pharmacogenomics program. SUMMARY: Clopidogrel-treated patients who are genetically predicted cytochrome P450 isozyme 2C19 (CYP2C19) intermediate or poor metabolizers have an increased risk of atherothrombotic events, some of which can be life-threatening. The Clinical Pharmacogenetics Implementation Consortium provides guidance for the use of clopidogrel based on CYP2C19 genotype in patients with cardiovascular and cerebrovascular diseases. Our multidisciplinary team implemented an automated, interruptive alert that fires when clopidogrel is ordered or refilled for biobank participants with structured CYP2C19 intermediate or poor metabolizer genomic indicators in the electronic health record. The implementation began with a narrow cardiovascular indication and setting and was then scaled in 4 primary dimensions: (1) clinical indication; (2) availability across health-system locations; (3) care venue (e.g., inpatient vs outpatient); and (4) provider groups (eg, cardiology and neurology). We iterated our approach over time based on evolving clinical evidence and proactive strategies to optimize CDS maintenance and sustainability. A key facilitator of expansion was socialization of the broader pharmacogenomics initiative among our academic medical center community, accompanied by clinician acceptance of pharmacogenetic alerts in practice. CONCLUSION: A multidisciplinary collaboration is recommended to facilitate the use of CYP2C19 genotype-guided antiplatelet therapy in patients with cardiovascular and cerebrovascular diseases. Evolving clopidogrel pharmacogenetic evidence necessitates thoughtful iteration of implementation efforts and strategies to optimize long-term maintenance and sustainability.

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The anthelmintic fenbendazole (FBZ) undergoes hepatic S­oxygenation 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 S­oxygenation, 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) S­oxygenation, 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 S­oxygenation 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 S­oxygenation 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.+.

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Aryl Hydrocarbon Receptor (AHR) signaling is crucial for regulating the biotransformation of xenobiotics and physiological processes like inflammation and immunity. Meanwhile, Thalassophryne nattereri Peptide (TnP), a promising anti-inflammatory candidate from toadfish venom, demonstrates therapeutic effects through immunomodulation. However, its influence on AHR signaling remains unexplored. This study aimed to elucidate TnP’s molecular mechanisms on the AHR–cytochrome P450, family 1 (CYP1) pathway upon injury-induced inflammation in wild-type (WT) and Ahr2-knockdown (KD) zebrafish larvae through transcriptomic analysis and Cyp1a reporters. TnP, while unable to directly activate AHR, potentiated AHR activation by the high-affinity ligand 6-Formylindolo [3,2-b]carbazole (FICZ), implying a role as a CYP1A inhibitor, confirmed by in vitro studies. This interplay suggests TnP’s ability to modulate the AHR-CYP1 complex, prompting investigations into its influence on biotransformation pathways and injury-induced inflammation. Here, the inflammation model alone resulted in a significant response on the transcriptome, with most differentially expressed genes (DEGs) being upregulated across the groups. Ahr2-KD resulted in an overall greater number of DEGs, as did treatment with the higher dose of TnP in both WT and KD embryos. Genes related to oxidative stress and inflammatory response were the most apparent under inflamed conditions for both WT and KD groups, e.g., Tnfrsf1a, Irf1b, and Mmp9. TnP, specifically, induces the expression of Hspa5, Hsp90aa1.2, Cxcr3.3, and Mpeg1.2. Overall, this study suggests an interplay between TnP and the AHR-CYP1 pathway, stressing the inflammatory modulation through AHR-dependent mechanisms. Altogether, these results may offer new avenues in novel therapeutic strategies, such as based on natural bioactive molecules, harnessing AHR modulation for targeted and sustained drug effects in inflammatory conditions.

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Dendroctonus-bark beetles are natural components and key ecological agents of coniferous forests. They spend most of their lives under the bark, where they are exposed to highly toxic terpenes present in the oleoresin. Cytochrome P450 (CYP) is a multigene family involved in the detoxification of these compounds. It has been demonstrated that CYP6DE and CYP6DJ subfamilies hydroxylate monoterpenes, whose derivatives can act as pheromone synergist compounds or be pheromones themselves in these insects. Given the diversity and functional role of CYPs, we investigated whether these cytochromes have retained their function throughout the evolution of these insects. To test this hypothesis, we performed a Bayesian phylogenetic analysis to determine phylogenetic subgroups of cytochromes in these subfamilies. Subgroups were mapped and reconciled with the Dendroctonus phylogeny. Molecular docking analyses were performed with the cytochromes of each subgroup and enantiomers of α-pinene and ß-pinene, (+)-3-carene, ß-myrcene and R-(+)-limonene. In addition, functional divergence analysis was performed to identify critical amino acid sites that influence changes in catalytic site conformation and/or protein folding. Three and two phylogenetic subgroups were recovered for the CYP6DE and CYP6DJ subfamilies, respectively. Mapping and reconciliation analysis showed different gain and loss patterns for cytochromes of each subgroup. Functional predictions indicated that the cytochromes analyzed are able to hydroxylate all monoterpenes; however, they showed preferential affinities to different monoterpenes. Functional divergence analyses indicated that the CYP6DE subfamily has experimented type I and II divergence, whereas the CYP6DJ subfamily has evolved under strong functional constraints. Results suggest cytochromes of the CYP6DE subfamily evolve to reinforce their detoxifying capacity hydroxylating mainly α- and ß-pinene to (+) and (-)-trans-verbenol, being the negative enantiomer used as a pheromone by several Dendroctonus species; whereas cytochromes of the CYP6DJ subfamily appear to retain their original function related to the detoxification of these compounds.

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BACKGROUND: Hypovitaminosis D is a public health problem due to its implications for various diseases. Vitamin D has numerous functions, such as modulating the metabolism of cellular tissues, and it is expressed through the vitamin D receptor (VDR) gene that may influence gene expression modulation, which plays an important role in vitamin D metabolism. OBJECTIVE: To evaluate the effect of the genotypes of BsmI single nucleotide polymorphism (SNP) of the VDR gene on VDR, SOD2, and CYP24A1 gene expression in individuals with low serum vitamin D levels. METHODS: This was a cross-sectional analytical study. After signing the informed consent form, individuals were invited to participate and answered a structured questionnaire with identification data. Blood was collected for biochemical analysis, and vitamin D was measured by chemiluminescence; BsmI polymorphism was determined using real-time polymerase chain reaction (PCR) assays with TaqMan allelic discrimination, and gene expression was conducted by qRT-PCR using QuantiFast SYBR® Green PCR Master Mix. Data were analyzed using the SPSS 20.0 software, and differences were considered significant at p < 0.05. RESULTS: 98 individuals with vitamin D ≤ 20 ng/dL were evaluated, and the BsmI SNP of the VDR gene showed CYP24A1 overexpression and low SOD2 expression. CONCLUSION: BsmI SNP of the VDR gene can modulate the expression of the genes evaluated without interfering with serum levels.

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Chrysene (CHR) is among the most persistent polycyclic aromatic hydrocarbons (PAH) in water and a priority compound for pollutants monitoring, due to its carcinogenic, mutagenic and genotoxic potential. Aquatic animals exposed to CHR may present alterations of biomarkers involved in the biotransformation and oxidative stress-related parameters. The aim of this study was to investigate differences in antioxidant and biotransformation (phase I and II) systems of Crassostrea gigas, C. gasar and C. rhizophorae and its effects resulting from CHR exposure. Adult oysters of these species were exposed to 10 µg L-1 of CHR for 24 h and 96 h. In gills, the transcripts CYP1-like, CYP2-like, CYP2AU1-like, GSTO-like, MGST-like, SULT-like were evaluated after 24 h of exposure. The activity of SOD, CAT, GPx, GR and G6PDH were analyzed in gills and digestive glands after 96 h of exposure. CHR bioaccumulated in tissues. Differences in the remaining levels of CHR in water after 96 h were observed in aquaria containing C. gigas or C. gasar oysters and may be associated to the different filtration rates between these species. Downregulate of biotransformation genes were observed in gills of C. gasar (CYP2AU1-like and GSTO-like) and C. rhizophorae (CYP1-like1, CYP2-like, MGST-like and SULT-like), suggesting that biotransformation responses may be species-specific. Differential activity of antioxidant enzymes were observed in gills and digestive gland of oysters exposed to CHR. Biochemical responses suggested that C. gigas and C. gasar are more responsive to CHR. Differential responses observed among the three Crassostrea species can be related to evolutionary differences, ecological niches and adaptation to environment.

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Herbicide mixtures are used to increase the spectrum of weed control and to manage weeds with target-site resistance to some herbicides. However, the effect of mixtures on the evolution of herbicide resistance caused by enhanced metabolism is unknown. This study evaluated the effect of a fenoxaprop-p-ethyl and imazethapyr mixture on the evolution of herbicide resistance in Echinochloa crus-galli using recurrent selection at sublethal doses. The progeny from second generations selected with the mixture had lower control than parental plants or the unselected progeny. GR50 increased 1.6- and 2.6-fold after two selection cycles with the mixture in susceptible (POP1-S) and imazethapyr-resistant (POP2-IR) biotypes, respectively. There was evidence that recurrent selection with this sublethal mixture had the potential to evolve cross-resistance to diclofop, cyhalofop, sethoxydim, and quinclorac. Mixture selection did not cause increased relative expression for a set of analyzed genes (CYP71AK2, CYP72A122, CYP72A258, CYP81A12, CYP81A14, CYP81A21, CYP81A22, and GST1). Fenoxaprop, rather than imazethapyr, is the main contributor to the decreased control in the progenies after recurrent selection with the mixture in low doses. This is the first study reporting the effect of a herbicide mixture at low doses on herbicide resistance evolution. The lack of control using the mixture may result in decreased herbicide sensitivity of the weed progenies. Using mixtures may select important detoxifying genes that have the potential to metabolize herbicides in patterns that cannot currently be predicted. The use of fully recommended herbicide rates in herbicide mixtures is recommended to reduce the risk of this type of resistance evolution.

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The soluble fraction of polysaccharides from cabernet franc red wine (SFP) previously showed antitumoral effects by modulating the immune system. The present study tested the hypothesis that the SFP can regulate CYPs in vitro in HepG2 cells and in vivo in Walker-256 tumor-bearing rats. The SFP was used in the following protocols: (i) solid tumor, (ii) liquid tumor, and (iii) chemopreventive solid tumor. The SFP reduced solid tumor growth in both solid tumor protocols but did not inhibit liquid tumor development. The SFP reduced total CYP levels in the solid and liquid tumor protocols and reduced the gene expression of Cyp1a1 and Cyp2e1 in rats and CYP1A2 in HepG2 cells. An increase of N-acetylglucosaminidase activity was observed in all SFP-treated rats, and TNF-α levels increased in the solid tumor protocol in the vehicle, SFP, and vincristine (positive control) groups. The chemopreventive solid tumor protocol did not modify CYP levels in the liver or intestine or N-acetylglucosaminidase and myeloperoxidase activity in the liver. The in vitro digestion and nuclear magnetic resonance analyses suggested that SFP was minimally modified in the gastrointestinal system. In conclusion, SFP inhibited CYPs both in vivo and in vitro, likely as a result of its immunoinflammatory actions.

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Bisphenol F (BPF) and Bisphenol S (BPS) are safe alternatives substances? Here Drosophila melanogaster were exposed during development (larval stage) to BPF and BPS (0.25, 0.5 and 1 mM). Upon reaching the last larval stage (3rd stage), markers of oxidative stress and metabolism of both substances were evaluated, along with investigation of mitochondrial and cell viability. This study is attributed to an unprecedented fact: BPF and BPS exposed larvae, both at concentrations of 0.5 and 1 mM, showed higher cytochrome P-450 (CYP450) activity. The GST activity increased in all BPF and BPS concentrations, and reactive species, lipid peroxidation, superoxide dismutase, and catalase activity increased in larvae (BPF and BPS; 0.5, and 1 mM); nonetheless, mitochondrial and cell viability decreased with 1 mM of BPF and BPS. In addition, the reduced number of pupae formed in the 1 mM BPF and BPS groups and melanotic mass formation may be attributed to oxidative stress. From the pupae formed, the hatching rate reduced in the 0.5 and 1 mM BPF and BPS groups. Thus, the possible presence of toxic metabolites may be related to the larval oxidative stress condition, which is detrimental to the complete development of Drosophila melanogaster.

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Purpose: To investigate whether interindividual variability in the CYP2C9 (*2 and *3 alleles) and VKORC1 (rs9923231) genes is associated with increased risk of upper gastrointestinal bleeding (UGIB) in users of non-steroidal anti-inflammatory drugs (NSAIDs) or low-dose aspirin (LDA). Methods: A full case-control study including 200 cases of patients diagnosed with UGIB and 706 controls was conducted in a Brazilian hospital complex. To perform an analysis of NSAIDs dose-effect, the defined daily dose (DDD) for NSAIDs was calculated in the 7-day etiologic window preceding the data index. Three categories of DDD, considering the genotypes of the genetic variants, were established: non-users of NSAIDs (DDD = 0), DDD ≤0.5, and DDD >0.5. Genetic variants and LDA or NSAIDs use synergism was estimated through Synergism Index (SI) and Relative Excess Risk Due To Interaction (RERI). Results: For DDDs of NSAIDs upward of 0.50, a risk of UGIB was identified in carriers of the *3 allele (OR: 15,650, 95% CI: 1.41-174.10) and in carriers of the variant homozygous genotype (TT) of rs9923231 (OR: 38,850, 95% CI: 2.70-556.00). In LDA users, the risk of UGIB was observed to be similar between carriers of the wild type homozygous genotype and carriers of the variant alleles for the CYP2C9 and VKORC1 genes. No synergism was identified. Conclusion: Our findings suggest an increased risk of UGIB in carriers of the variant allele of rs9923231 and in carriers of the *3 allele associated with doses of NSAIDs greater than 0.5. Hence, the assessment of these variants might reduce the incidence of NSAIDs-related UGIB and contribute to the safety of the NSAIDs user.

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The South American tomato moth, Phthorimaea absoluta (Meyrick), is one of the key pests of tomato in India. Since its report in 2014, chemical control has been the main means of tackling this pest, both in the open field and protected cultivation. Despite regular insecticidal sprays, many outbreaks were reported from major tomato-growing regions of South India during 2019-2020. A study was conducted to investigate the effect of insecticide resistance on biology, biochemical enzymes, and gene expression in various P. absoluta field populations viz., Bangalore, Kolar, Madurai, Salem, and Anantapur to commonly used insecticides such as flubendiamide, cyantraniliprole, and indoxacarb. Increased levels of insecticide resistance ratios (RR) were recorded in P. absoluta populations of different locations. A significant increase in cytochrome P450 monooxygenase (CYP/MFO) and esterase levels was noticed in the resistant population compared to susceptible one. Through molecular studies, we identified four new CYP genes viz., CYP248f (flubendiamide), CYP272c, CYP724c (cyantraniliprole), and CYP648i (indoxacarb). The expression levels of these genes significantly increased as the folds of resistance increased from G1 to G20 (generation), indicating involvement of the identified genes in insecticide resistance development in P. absoluta. In addition, the resistant populations showed decreased fecundity, increased larval development period, and adult longevity, resulting in more crop damage. The information generated in the present study thus helps in understanding the development of insecticide resistance by P. absoluta and suggests the farmers and researchers to use insecticides wisely by adopting insecticide resistance management as a strategy under integrated pest management.

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Introdução: A malária continua sendo um grave problema de saúde pública mundial, dado os elevados índices anuais de morbimortalidade. O tratamento baseia-se no uso de medicamentos, entretanto, a resistência dos parasitos aos medicamentos disponíveis tem se tornado uma realidade alarmante, o que torna urgente o desenvolvimento de novos fármacos com atividade antimalárica. Em um estudo prévio, selecionou-se três alcaloides ß-carbolínicos que apresentaram atividade antimalárica. Dessa forma, o presente trabalho se propôs a dar continuidade ao estudo dessas moléculas avaliando o perfil de metabolismo e toxicidade hepática. Objetivo: Avaliar o perfil de metabolismo e toxicidade hepática de três alcaloides ß-carbolínicos (1, 2 e 3) selecionados em estudo prévio, que apresentaram atividade antimalárica in vitro e in vivo.Material e Métodos: Trata-se de um estudo de abordagem tanto qualitativa quanto quantitativa com caráter experimental e analítico. Foi realizada análise in silico das propriedades de metabolismo e toxicidade dos alcaloides empregando a notação SMILES por meio do programa AdmetSAR 2.0. A toxicidade hepática foi avaliada por meio da análise bioquímica da aspartato aminotrasferase (AST) e alanina aminotransferase (ALT) no soro de camundongos da linhagem C57BL/6, tratados com os alcaloides ou com cloroquina. Resultados: Na análise in silico foi observada a predição de baixo potencial hepatotóxico para os alcaloides 1 e 2, sendo este resultado corroborado pela dosagem de ALT, que apresentou resultados semelhantes ao do grupo controle. O alcaloide 3, no entanto, apresentou dados contrastantes, indicando potencial hepatotóxico na predição in silico, porém, baixo potencial em análise in vivo, com valores de ALT também próximos do grupo controle. Todos os alcaloides em estudo apresentaram potencial para interações medicamentosas. Conclusão: Os alcaloides avaliados nesse estudo apresentaram parâmetros metabólicos e de toxicidade promissores, podendo ser bons adjuvantes à farmacoterapia da malária. Entretanto, esses resultados precisam ser confirmados para seguimento das moléculas nos estudos pré-clínicos.

Introduction: Malaria continues to be a serious global public health problem, given the high annual morbidity and mortality rates. It is caused by protozoa of the genus Plasmodium, with P. falciparum responsible for most serious cases and deaths. Treatment is based on the use of drugs, however, the resistance of parasites to available drugs has become an alarming reality, which makes the development of new drugs with antimalarial activity urgent. In a previous study, our research group selected three ß-carboline alkaloids that showed antimalarial activity. Therefore, the present work proposed to continue the study of these molecules by evaluating the metabolism profile and liver toxicity. Objective: To evaluate the metabolism and liver toxicity profile of three ß-carboline alkaloids (1, 2 and 3) selected in a previous study, which showed antimalarial activity in vitro and in vivo. Material and Methods: This is a study with both a qualitative and quantitative approach with an experimental and analytical nature. In silico analysis of the metabolism and toxicity properties of alkaloids was carried out using the SMILES notation through the AdmetSAR 2.0 program. Liver toxicity was evaluated through biochemical analysis of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in the serum of mice of the C57BL/6 lineage, treated with the alkaloids or chloroquine. Results: In the in silico analysis, the prediction of low hepatotoxic potential for alkaloids 1 and 2 was observed, and this result was corroborated by the ALT dosage, which presented results similar to those of the control group. Alkaloid 3, however, presented contrasting data, indicating hepatotoxic potential in in silico prediction, however, low potential in in vivo analysis, with ALT values also close to the control group. All alkaloids under study showed potential for drug interactions. Conclusion: The alkaloids evaluated in this study showed promising metabolic and toxicity parameters and could be good adjuvants for malaria pharmacotherapy. However, these results need to be confirmed to follow the molecules in preclinical studies.

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Fenbendazole (FBZ), a benzymidazole (BZD) anthelmintic drug, is used for in-feed medication in pigs. BZD-containing drugs may induce cytochrome P450 isozymes (CYPs), particularly those members of the CYP1A subfamily. The current research evaluated the plasma and liver availability and metabolism of FBZ and its metabolites, oxfendazole (OFZ) and fenbendazole sulphone (FBZSO2), after the administration of the parent drug in feed, and characterized the effect of the sustained administration of the anthelmintic on the catalytic activities of xenobiotic metabolizing enzymes in pig liver. Five female Landrace piglets remained untreated (controls), and other six were treated with a pre-mix of FBZ, combined with feed, for 9 consecutive days as usually is recommended. Blood samples were collected from each treated animal up to day 9 and analyzed by HPLC; all animals were slaughtered for preparation of liver microsomes. Plasma concentration ratios OFZ/FBZ and FBZSO2/OFZ increased significantly (p < 0.05) from the beginning to the end of drug exposure, which may indicate an enhanced conversion of FBZ into its metabolites. FBZ represented 45.8 ± 3.4% of the total anthelmintic molecules in liver tissue. Increased CYP1A-dependent 7-ethoxy (24.5-fold, p = 0.0032) and 7-methoxyresorufin (17.2-fold, p = 0.0006) O-dealkylase activities was observed in liver microsomes from FBZ-treated animals. In addition, a 64% increase (p = 0.042) in the rate of FBZ S-oxidation was observed in pigs treated with the anthelmintic drug compared to that measured in untreated animals. Thus, the continuous FBZ administration may accelerate its own in vivo hepatic metabolism through the CYP1A pathway.

Assuntos

RESUMO

Oysters are frequently used as sentinel organisms for monitoring effects of contaminants due to their sessile, filtering habits and bioaccumulation capacity. These animals can show elevated body burden of contaminants, such as pyrene (PYR). PYR can be toxic at a molecular level until the whole oyster, which can show reproductive and behavioral changes. Considering that biologic parameters, such as gender or reproductive stage can interfere in the toxic effects elicited by contaminants uptake, the aim of this study was to evaluate some molecular and histological responses in females and males of oyster Crassostrea gasar exposed to PYR (0.25 and 0.5 µM) for 24 h at the pre-spawning stage. PYR concentrations were analyzed in water and in tissues of female and male oysters. Gene transcripts related to biotransformation (CYP3475C, CYP2-like, CYP2AU1, CYP356A, GSTO-like, GSTM-like, SULT-like), stress (HSP70), and reproduction (Vitellogenin, Glycoprotein) were quantified in gills. In addition, histological analysis and histo-localization of CYP2AU1 mRNA transcripts in gills, mantle and digestive diverticulum were carried out. Females and males in pre-spawning stage bioconcentrated PYR in their tissues. Males were more sensitive to PYR exposure. CYP2AU1 transcripts were higher in males (p < 0.05), as well as tubular atrophy was observed only in males exposed to PYR (p < 0.05). As expected, vitellogenin transcripts were lower in males (p < 0.05). Given these results, it is suggested that levels of CYP2AU1 be a good biomarker of exposure to PYR in oyster C. gasar and that it is important to consider the gender for the interpretation of biomarker responses.

Assuntos

RESUMO

The high morbidity and mortality rates of Candida infections, especially among immunocompromised patients, are related to the increased resistance rate of these species and the limited therapeutic arsenal. In this context, we evaluated the anti-Candida potential and the cytotoxic profile of eugenol derivatives. Anti-Candida activity was evaluated on C. albicans and C. parapsilosis strains by minimum inhibitory concentration (MIC), scanning electron microscopy (SEM), and molecular docking calculations at the site of the enzyme lanosterol-14-α-demethylase active site, responsible for ergosterol formation. The cytotoxic profile was evaluated in HepG2 cells, in the presence and absence of the metabolizing system (S9 system). The results indicated compounds 1b and 1d as the most active ones. The compounds have anti-Candida activity against both strains with MIC ranging from 50 to 100 µg ml-1 . SEM analyses of 1b and 1d indicated changes in the envelope architecture of both C. albicans and C. parapsilosis like the ones of eugenol and fluconazole, respectively. Docking results of the evaluated compounds indicated a similar binding pattern of fluconazole and posaconazole at the lanosterol-14-α-demethylase binding site. In the presence of the S9 system, compound 1b showed the same cytotoxicity profile as fluconazole (1.08 times) and compound 1d had 1.23 times increase in cytotoxicity. Eugenol and other evaluated compounds showed a significant increase in cytotoxicity. Our results suggest compound 1b as a promising starting point candidate to be used in the design of new anti-Candida agent prototypes.

Assuntos