1
|
Allard J, Bucher S, Ferron PJ, Launay Y, Fromenty B. Busulfan induces steatosis in HepaRG cells but not in primary human hepatocytes: Possible explanations and implication for the prediction of drug-induced liver injury. Fundam Clin Pharmacol 2024; 38:152-167. [PMID: 37665028 DOI: 10.1111/fcp.12951] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Revised: 07/27/2023] [Accepted: 08/10/2023] [Indexed: 09/05/2023]
Abstract
BACKGROUND The antineoplastic drug busulfan can induce different hepatic lesions including cholestasis and sinusoidal obstruction syndrome. However, hepatic steatosis has never been reported in patients. OBJECTIVES This study aimed to determine whether busulfan could induce steatosis in primary human hepatocytes (PHH) and differentiated HepaRG cells. METHODS Neutral lipids were determined in PHH and HepaRG cells. Mechanistic investigations were performed in HepaRG cells by measuring metabolic fluxes linked to lipid homeostasis, reduced glutathione (GSH) levels, and expression of genes involved in lipid metabolism and endoplasmic reticulum (ER) stress. Analysis of two previous transcriptomic datasets was carried out. RESULTS Busulfan induced lipid accumulation in HepaRG cells but not in six different batches of PHH. In HepaRG cells, busulfan impaired VLDL secretion, increased fatty acid uptake, and induced ER stress. Transcriptomic data analysis and decreased GSH levels suggested that busulfan-induced steatosis might be linked to the high expression of glutathione S-transferase (GST) isoenzyme A1, which is responsible for the formation of the hepatotoxic sulfonium cation conjugate. In keeping with this, the GST inhibitor ethacrynic acid and the chemical chaperone tauroursodeoxycholic acid alleviated busulfan-induced lipid accumulation in HepaRG cells supporting the role of the sulfonium cation conjugate and ER stress in steatosis. CONCLUSION While the HepaRG cell line is an invaluable tool for pharmacotoxicological studies, it might not be always an appropriate model to predict and mechanistically investigate drug-induced liver injury. Hence, we recommend carrying out toxicological investigations in both HepaRG cells and PHH to avoid drawing wrong conclusions on the potential hepatotoxicity of drugs and other xenobiotics.
Collapse
|
2
|
Granados AA, Bucher S, Song H, Agrawal A, Chen AT, Peng T, Neff N, Pisco AO, Huang F, Wang B. Single-nuclei characterization of pervasive transcriptional signatures across organs in response to COVID-19. eLife 2023; 12:e81090. [PMID: 37830426 PMCID: PMC10575628 DOI: 10.7554/elife.81090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Accepted: 07/16/2023] [Indexed: 10/14/2023] Open
Abstract
Background Infection by coronavirus SARS-CoV2 is a severe and often deadly disease that has implications for the respiratory system and multiple organs across the human body. While the effects in the lung have been extensively studied, less is known about the impact COVID-19 has across other organs. Methods Here, we contribute a single-nuclei RNA-sequencing atlas comprising six human organs across 20 autopsies where we analyzed the transcriptional changes due to COVID-19 in multiple cell types. The integration of data from multiple organs enabled the identification of systemic transcriptional changes. Results Computational cross-organ analysis for endothelial cells and macrophages identified systemic transcriptional changes in these cell types in COVID-19 samples. In addition, analysis of gene modules showed enrichment of specific signaling pathways across multiple organs in COVID-19 autopsies. Conclusions Altogether, the COVID Tissue Atlas enables the investigation of both cell type-specific and cross-organ transcriptional responses to COVID-19, providing insights into the molecular networks affected by the disease and highlighting novel potential targets for therapies and drug development. Funding The Chan-Zuckerberg Initiative, The Chan-Zuckerberg Biohub.
Collapse
|
3
|
Song H, Bucher S, Rosenberg K, Tsui M, Burhan D, Hoffman D, Cho SJ, Rangaswami A, Breese M, Leung S, Ventura MVP, Sweet-Cordero EA, Huang FW, Nijagal A, Wang B. Single-cell analysis of hepatoblastoma identifies tumor signatures that predict chemotherapy susceptibility using patient-specific tumor spheroids. Nat Commun 2022; 13:4878. [PMID: 36008377 PMCID: PMC9411569 DOI: 10.1038/s41467-022-32473-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Accepted: 08/02/2022] [Indexed: 11/22/2022] Open
Abstract
Pediatric hepatoblastoma is the most common primary liver cancer in infants and children. Studies of hepatoblastoma that focus exclusively on tumor cells demonstrate sparse somatic mutations and a common cell of origin, the hepatoblast, across patients. In contrast to the homogeneity these studies would suggest, hepatoblastoma tumors have a high degree of heterogeneity that can portend poor prognosis. In this study, we use single-cell transcriptomic techniques to analyze resected human pediatric hepatoblastoma specimens, and identify five hepatoblastoma tumor signatures that may account for the tumor heterogeneity observed in this disease. Notably, patient-derived hepatoblastoma spheroid cultures predict differential responses to treatment based on the transcriptomic signature of each tumor, suggesting a path forward for precision oncology for these tumors. In this work, we define hepatoblastoma tumor heterogeneity with single-cell resolution and demonstrate that patient-derived spheroids can be used to evaluate responses to chemotherapy.
Collapse
|
4
|
Imran M, Chalmel F, Sergent O, Evrard B, Le Mentec H, Legrand A, Dupont A, Bescher M, Bucher S, Fromenty B, Huc L, Sparfel L, Lagadic-Gossmann D, Podechard N. Transcriptomic analysis in zebrafish larvae identifies iron-dependent mitochondrial dysfunction as a possible key event of NAFLD progression induced by benzo[a]pyrene/ethanol co-exposure. Cell Biol Toxicol 2022:10.1007/s10565-022-09706-4. [PMID: 35412187 DOI: 10.1007/s10565-022-09706-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 02/28/2022] [Indexed: 11/02/2022]
Abstract
Non-alcoholic fatty liver disease (NAFLD) is a worldwide epidemic for which environmental contaminants are increasingly recognized as important etiological factors. Among them, the combination of benzo[a]pyrene (B[a]P), a potent environmental carcinogen, with ethanol, was shown to induce the transition of steatosis toward steatohepatitis. However, the underlying mechanisms involved remain to be deciphered. In this context, we used high-fat diet fed zebrafish model, in which we previously observed progression of steatosis to a steatohepatitis-like state following a 7-day-co-exposure to 43 mM ethanol and 25 nM B[a]P. Transcriptomic analysis highlighted the potent role of mitochondrial dysfunction, alterations in heme and iron homeostasis, involvement of aryl hydrocarbon receptor (AhR) signaling, and oxidative stress. Most of these mRNA dysregulations were validated by RT-qPCR. Moreover, similar changes were observed using a human in vitro hepatocyte model, HepaRG cells. The mitochondria structural and functional alterations were confirmed by transmission electronic microscopy and Seahorse technology, respectively. Involvement of AhR signaling was evidenced by using in vivo an AhR antagonist, CH223191, and in vitro in AhR-knock-out HepaRG cells. Furthermore, as co-exposure was found to increase the levels of both heme and hemin, we investigated if mitochondrial iron could induce oxidative stress. We found that mitochondrial labile iron content was raised in toxicant-exposed larvae. This increase was prevented by the iron chelator, deferoxamine, which also inhibited liver co-exposure toxicity. Overall, these results suggest that the increase in mitochondrial iron content induced by B[a]P/ethanol co-exposure causes mitochondrial dysfunction that contributes to the pathological progression of NAFLD.
Collapse
|
5
|
Bresnahan BW, Vodicka E, Babigumira JB, Malik AM, Yego F, Lokangaka A, Chitah BM, Bauer Z, Chavez H, Moore JL, Garrison LP, Swanson JO, Swanson D, McClure EM, Goldenberg RL, Esamai F, Garces AL, Chomba E, Saleem S, Tshefu A, Bose CL, Bauserman M, Carlo W, Bucher S, Liechty EA, Nathan RO. Cost estimation alongside a multi-regional, multi-country randomized trial of antenatal ultrasound in five low-and-middle-income countries. BMC Public Health 2021; 21:952. [PMID: 34016085 PMCID: PMC8135981 DOI: 10.1186/s12889-021-10750-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 04/04/2021] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND Improving maternal health has been a primary goal of international health agencies for many years, with the aim of reducing maternal and child deaths and improving access to antenatal care (ANC) services, particularly in low-and-middle-income countries (LMICs). Health interventions with these aims have received more attention from a clinical effectiveness perspective than for cost impact and economic efficiency. METHODS We collected data on resource use and costs as part of a large, multi-country study assessing the use of routine antenatal screening ultrasound (US) with the aim of considering the implications for economic efficiency. We assessed typical antenatal outpatient and hospital-based (facility) care for pregnant women, in general, with selective complication-related data collection in women participating in a large maternal health registry and clinical trial in five LMICs. We estimated average costs from a facility/health system perspective for outpatient and inpatient services. We converted all country-level currency cost estimates to 2015 United States dollars (USD). We compared average costs across countries for ANC visits, deliveries, higher-risk pregnancies, and complications, and conducted sensitivity analyses. RESULTS Our study included sites in five countries representing different regions. Overall, the relative cost of individual ANC and delivery-related healthcare use was consistent among countries, generally corresponding to country-specific income levels. ANC outpatient visit cost estimates per patient among countries ranged from 15 to 30 USD, based on average counts for visits with and without US. Estimates for antenatal screening US visits were more costly than non-US visits. Costs associated with higher-risk pregnancies were influenced by rates of hospital delivery by cesarean section (mean per person delivery cost estimate range: 25-65 USD). CONCLUSIONS Despite substantial differences among countries in infrastructures and health system capacity, there were similarities in resource allocation, delivery location, and country-level challenges. Overall, there was no clear suggestion that adding antenatal screening US would result in either major cost savings or major cost increases. However, antenatal screening US would have higher training and maintenance costs. Given the lack of clinical effectiveness evidence and greater resource constraints of LMICs, it is unlikely that introducing antenatal screening US would be economically efficient in these settings--on the demand side (i.e., patients) or supply side (i.e., healthcare providers). TRIAL REGISTRATION Trial number: NCT01990625 (First posted: November 21, 2013 on https://clinicaltrials.gov ).
Collapse
|
6
|
Jessani S, Saleem S, Hoffman MK, Goudar SS, Derman RJ, Moore JL, Garces A, Figueroa L, Krebs NF, Okitawutshu J, Tshefu A, Bose CL, Mwenechanya M, Chomba E, Carlo WA, Das PK, Patel A, Hibberd PL, Esamai F, Liechty EA, Bucher S, Nolen TL, Koso-Thomas M, Miodovnik M, McClure EM, Goldenberg RL. Association of haemoglobin levels in the first trimester and at 26-30 weeks with fetal and neonatal outcomes: a secondary analysis of the Global Network for Women's and Children's Health's ASPIRIN Trial. BJOG 2021; 128:1487-1496. [PMID: 33629490 DOI: 10.1111/1471-0528.16676] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/27/2021] [Indexed: 11/29/2022]
Abstract
OBJECTIVE Limited data are available from low- and middle-income countries (LMICs) on the relationship of haemoglobin levels to adverse outcomes at different times during pregnancy. We evaluated the association of haemoglobin levels in nulliparous women at two times in pregnancy with pregnancy outcomes. DESIGN ASPIRIN Trial data were used to study the association between haemoglobin levels measured at 6+0 -13+6 weeks and 26+0 -30+0 weeks of gestation with fetal and neonatal outcomes. SETTING Obstetric care facilities in Pakistan, India, Kenya, Zambia, The Democratic Republic of the Congo and Guatemala. POPULATION A total of 11 976 pregnant women. METHODS Generalised linear models were used to obtain adjusted relative risks and 95% CI for adverse outcomes. MAIN OUTCOME MEASURES Preterm birth, stillbirth, neonatal death, small for gestational age (SGA) and birthweight <2500 g. RESULTS The mean haemoglobin levels at 6+0 -13+6 weeks and at 26-30 weeks of gestation were 116 g/l (SD 17) and 107 g/l (SD 15), respectively. In general, pregnancy outcomes were better with increasing haemoglobin. At 6+0 -13+6 weeks of gestation, stillbirth, SGA and birthweight <2500 g, were significantly associated with haemoglobin of 70-89 g/l compared with haemoglobin of 110-129 g/l The relationships of adverse pregnancy outcomes with various haemoglobin levels were more marked at 26-30 weeks of gestation. CONCLUSIONS Both lower and some higher haemoglobin concentrations are associated with adverse fetal and neonatal outcomes at 6+0 -13+6 weeks and at 26-30 weeks of gestation, although the relationship with low haemoglobin levels appears more consistent and generally stronger. TWEETABLE ABSTRACT Both lower and some higher haemoglobin concentrations were associated with adverse fetal and neonatal outcomes at 6-13 weeks and 26-30 weeks of gestation.
Collapse
|
7
|
Allard J, Bucher S, Massart J, Ferron PJ, Le Guillou D, Loyant R, Daniel Y, Launay Y, Buron N, Begriche K, Borgne-Sanchez A, Fromenty B. Drug-induced hepatic steatosis in absence of severe mitochondrial dysfunction in HepaRG cells: proof of multiple mechanism-based toxicity. Cell Biol Toxicol 2021; 37:151-175. [PMID: 32535746 PMCID: PMC8012331 DOI: 10.1007/s10565-020-09537-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Accepted: 06/02/2020] [Indexed: 02/07/2023]
Abstract
Steatosis is a liver lesion reported with numerous pharmaceuticals. Prior studies showed that severe impairment of mitochondrial fatty acid oxidation (mtFAO) constantly leads to lipid accretion in liver. However, much less is known about the mechanism(s) of drug-induced steatosis in the absence of severe mitochondrial dysfunction, although previous studies suggested the involvement of mild-to-moderate inhibition of mtFAO, increased de novo lipogenesis (DNL), and impairment of very low-density lipoprotein (VLDL) secretion. The objective of our study, mainly carried out in human hepatoma HepaRG cells, was to investigate these 3 mechanisms with 12 drugs able to induce steatosis in human: amiodarone (AMIO, used as positive control), allopurinol (ALLO), D-penicillamine (DPEN), 5-fluorouracil (5FU), indinavir (INDI), indomethacin (INDO), methimazole (METHI), methotrexate (METHO), nifedipine (NIF), rifampicin (RIF), sulindac (SUL), and troglitazone (TRO). Hepatic cells were exposed to drugs for 4 days with concentrations decreasing ATP level by less than 30% as compared to control and not exceeding 100 × Cmax. Among the 12 drugs, AMIO, ALLO, 5FU, INDI, INDO, METHO, RIF, SUL, and TRO induced steatosis in HepaRG cells. AMIO, INDO, and RIF decreased mtFAO. AMIO, INDO, and SUL enhanced DNL. ALLO, 5FU, INDI, INDO, SUL, RIF, and TRO impaired VLDL secretion. These seven drugs reduced the mRNA level of genes playing a major role in VLDL assembly and also induced endoplasmic reticulum (ER) stress. Thus, in the absence of severe mitochondrial dysfunction, drug-induced steatosis can be triggered by different mechanisms, although impairment of VLDL secretion seems more frequently involved, possibly as a consequence of ER stress.
Collapse
|
8
|
Steiner UC, Bischoff S, Valaperti A, Ikenberg K, Starzyk J, Bucher S, Bachmann LM, Soyka MB. Endotypes of chronic rhinosinusitis with nasal polyps with and without NSAID â€" intolerance. Rhinology 2021; 58:544-549. [PMID: 32692786 DOI: 10.4193/rhin19.423] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND Chronic rhinosinusitis with nasal polyps (CRSwNP) is a type 2-dominated inflammatory disease of the upper air- ways. A subgroup of patients with CRSwNP suffer from intolerance to nonsteroidal anti-inflammatory drugs (NSAID) and develop NSAID-exacerbated respiratory disease (NERD). The aim of the study was to compare the cytokine based inflammatory endotype of nasal secretions of CRSwNP patients with and without NSAID intolerance. METHODS Nasal secretions were collected from twenty-six patients suffering from CRSwNP, thirteen with NERD and thirteen without NSAID intolerance. As control, nasal secretions were collected from fifteen healthy donors. Tryptase and ten human cyto- kines were analyzed: interleukin (IL)-4, IL-5, IL-6, IL-8, IL-12p70, IL-13, IL-17A, IL-23, IFN-g, and TNF-a by a cytokine multiple array on a Luminex 200 platform. RESULTS Grade of polyposis and frequency of polyp surgery was more severe in NERD- compared to non-NERD patients. IL-6 and IL-5 in CRSwNP was significantly increased compared to healthy participants. IL-5 and IL-13 were significantly increased in subjects suffering from NERD compared to CRSwNP patients without NERD. CONCLUSION We identified IL-13 as a possible specific biomarker in nasal secretions of patients with NERD, which allows us to differentiate between CRSwNP with vs. without NERD. The characterization of inflammatory endotypes in CRSwNP enables the introduction of the best available therapy in the context of precision medicine.
Collapse
|
9
|
Bucher S, Kunz S, Deggeller M, Holzmann D, Soyka MB. Open rhinoplasty using a columellar strut: effects of the graft on nasal tip projection and rotation. Eur Arch Otorhinolaryngol 2020; 277:1371-1377. [PMID: 32062744 DOI: 10.1007/s00405-020-05836-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Accepted: 01/30/2020] [Indexed: 11/25/2022]
Abstract
BACKGROUND Despite the discordance in the literature concerning the effect of columellar strut grafts on nasal tip rotation, this method is often used when an increase in nasolabial angle or nasal tip projection is desired. OBJECTIVES We aimed to elucidate the change in nasolabial angles and nasal tip projections after exclusive columellar strut graft implantations and in addition to other surgical steps. Furthermore, differences in these parameters between patients with conchal and septal columellar strut grafts were investigated. METHODS A monocentric retrospective cohort study of 173 open septorhinoplasties with columellar strut graft technique, between 2006 and 2016, was conducted. The pre- and postoperative nasal tip projection, nasolabial and nasofrontal angle and interalar distance were determined and the Goode-ratio was calculated. RESULTS In cases where uprotation was not specifically desired, neither nasolabial angles nor tip projections changed significantly, irrespective of whether a columellar strut graft was used alone or with additional surgical steps. If an uprotation through surgery was desired, a significant mean increase in nasolabial angle of 4.4° was achieved. Furthermore, conchal instead of septal columellar strut grafts showed significantly better results. CONCLUSION In our study, a columellar strut graft-without any additional surgical step-does only have an improving impact on nasal tip rotations and projections, if specifically intended to by the surgeon. In other words, if the strut graft was not chosen for an uprotational intention, it did not relevantly impact on the nasolabial angle or nasal tip projection. However, in patients where an uprotation is desired, the columellar strut graft still represents a meaningful tool. Since conchal instead of septal columellar strut grafts showed better results, we suggest using them for these patients. LEVEL OF EVIDENCE 2b.
Collapse
|
10
|
van Meteren N, Lagadic-Gossmann D, Chevanne M, Gallais I, Gobart D, Burel A, Bucher S, Grova N, Fromenty B, Appenzeller BMR, Chevance S, Gauffre F, Le Ferrec E, Sergent O. Polycyclic aromatic hydrocarbons can trigger hepatocyte release of extracellular vesicles by various mechanisms of action depending on their affinity for the aryl hydrocarbon receptor. Toxicol Sci 2019; 171:443-462. [PMID: 31368503 DOI: 10.1093/toxsci/kfz157] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Revised: 07/08/2019] [Accepted: 07/09/2019] [Indexed: 12/19/2022] Open
Abstract
Extracellular vesicles (EVs) are membrane enclosed nanostructures released by cells into the extracellular environment. As major actors of physiological intercellular communication, they have been shown to be pathogenic mediators of several liver diseases. EVs also appear to be potential actors of drug-induced liver injury, but nothing is known concerning environmental pollutants. We aimed to study the impact of polycyclic aromatic hydrocarbons (PAHs), major contaminants, on hepatocyte-derived EV production, with a special focus on hepatocyte death. Three PAHs were selected, based on their presence in food and their affinity for the aryl hydrocarbon receptor (AhR): benzo(a)pyrene (BP), dibenzo(a,h)anthracene (DBA), and pyrene (PYR). Treatment of primary rat and WIF-B9 hepatocytes by all three PAHs increased the release of EVs, mainly comprised of exosomes, in parallel with modifying exosome protein marker expression and inducing apoptosis. Moreover, PAH treatment of rodents for three months also led to increased EV levels in plasma. The EV release involved CYP metabolism and the activation of the transcription factor, the AhR, for BP and DBA and another transcription factor, the constitutive androstane receptor (CAR), for PYR. Furthermore, all PAHs increased cholesterol levels in EVs but only BP and DBA were able to reduce the cholesterol content of total cell membranes. All cholesterol changes very likely participated in the increase in EV release and cell death. Finally, we studied changes in cell membrane fluidity caused by BP and DBA due to cholesterol depletion. Our data showed increased cell membrane fluidity, which contributed to hepatocyte EV release and cell death.
Collapse
|
11
|
Tête A, Gallais I, Imran M, Chevanne M, Liamin M, Sparfel L, Bucher S, Burel A, Podechard N, Appenzeller BMR, Fromenty B, Grova N, Sergent O, Lagadic-Gossmann D. Mechanisms involved in the death of steatotic WIF-B9 hepatocytes co-exposed to benzo[a]pyrene and ethanol: a possible key role for xenobiotic metabolism and nitric oxide. Free Radic Biol Med 2018; 129:323-337. [PMID: 30268890 DOI: 10.1016/j.freeradbiomed.2018.09.042] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Revised: 09/20/2018] [Accepted: 09/26/2018] [Indexed: 12/15/2022]
Abstract
We previously demonstrated that co-exposing pre-steatotic hepatocytes to benzo[a]pyrene (B[a]P), a carcinogenic environmental pollutant, and ethanol, favored cell death. Here, the intracellular mechanisms underlying this toxicity were studied. Steatotic WIF-B9 hepatocytes, obtained by a 48h-supplementation with fatty acids, were then exposed to B[a]P/ethanol (10 nM/5 mM, respectively) for 5 days. Nitric oxide (NO) was demonstrated to be a pivotal player in the cell death caused by the co-exposure in steatotic hepatocytes. Indeed, by scavenging NO, CPTIO treatment of co-exposed steatotic cells prevented not only the increase in DNA damage and cell death, but also the decrease in the activity of CYP1, major cytochrome P450s of B[a]P metabolism. This would then lead to an elevation of B[a]P levels, thus possibly suggesting a long-lasting stimulation of the transcription factor AhR. Besides, as NO can react with superoxide anion to produce peroxynitrite, a highly oxidative compound, the use of FeTPPS to inhibit its formation indicated its participation in DNA damage and cell death, further highlighting the important role of NO. Finally, a possible key role for AhR was pointed out by using its antagonist, CH-223191. Indeed it prevented the elevation of ADH activity, known to participate to the ethanol production of ROS, notably superoxide anion. The transcription factor, NFκB, known to be activated by ROS, was shown to be involved in the increase in iNOS expression. Altogether, these data strongly suggested cooperative mechanistic interactions between B[a]P via AhR and ethanol via ROS production, to favor cell death in the context of prior steatosis.
Collapse
|
12
|
Bucher S, Kugler A, Probst E, Epprecht L, Stadler RR, Holzmann D, Soyka MB. Occurrence of occult CSF leaks during standard FESS procedures. Rhinology 2018; 56:166-171. [PMID: 29550855 DOI: 10.4193/rhin17.117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVE To determine the incidence of occult cerebrospinal fluid leaks (CSF) after functional endoscopic sinus surgery (FESS) and to evaluate the diagnostic performance of beta2-transferrin in blood-contaminated conditions. STUDY DESIGN Prospective cohort study. METHODS An analysis of 57 intraoperative samples using hydrogel 6 beta2-transferrin assay after FESS was undertaken. In case of CSF positive samples and continuing rhinorrhea, reanalysis after more than 1 year was conducted. In-vivo analysis of a primary spontaneous CSF leak sample took place to verify difficulties in detecting beta2-transferrin in blood-contaminated settings. Own titrations were performed to evaluate detection limits of CSF by beta2-transferrin and beta-trace protein assays in these settings. RESULTS An incidence of 13% for occult CSF leaks after FESS was found. In blood-contaminated conditions, routine beta2-transferrin assays showed low sensitivity. In over 1 year follow-up, all samples were negative for CSF and none of them developed clinical relevant CSF leaks or meningitis. CONCLUSION Occult and clinically irrelevant CSF leaks do occur in a significant proportion of patients during and shortly after FESS. Intra- and postoperatively, routine beta2-transferrin assays show low sensitivity. They should not be used in these settings. The clinical course of patients with occult CSF leaks indicated possibility of an uneventful follow-up.
Collapse
|
13
|
Quesnot N, Bucher S, Gade C, Vlach M, Vene E, Valença S, Gicquel T, Holst H, Robin MA, Loyer P. Production of chlorzoxazone glucuronides via cytochrome P4502E1 dependent and independent pathways in human hepatocytes. Arch Toxicol 2018; 92:3077-3091. [PMID: 30151596 DOI: 10.1007/s00204-018-2300-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Accepted: 08/23/2018] [Indexed: 12/28/2022]
Abstract
CYP2E1 activity is measured in vitro and in vivo via hydroxylation of the Chlorzoxazone (CHZ) producing the 6-hydroxychlorzoxazone (OH-CHZ) further metabolized as a glucuronide excreted in urine. Thus, the quantification of the OH-CHZ following enzymatic hydrolysis of CHZ-derived glucuronide appears to be a reliable assay to measure the CYP2E1 activity without direct detection of this glucuronide. However, OH-CHZ hydrolyzed from urinary glucuronide accounts for less than 80% of the CHZ administrated dose in humans leading to postulate the production of other unidentified metabolites. Moreover, the Uridine 5'-diphospho-glucuronosyltransferase (UGT) involved in the hepatic glucuronidation of OH-CHZ has not yet been identified. In this study, we used recombinant HepG2 cells expressing CYP2E1, metabolically competent HepaRG cells, primary hepatocytes and precision-cut human liver slices to identify metabolites of CHZ (300 μM) by high pressure liquid chromatography-UV and liquid-chromatography-mass spectrometry analyses. Herein, we report the detection of the CHZ-O-glucuronide (CHZ-O-Glc) derived from OH-CHZ in culture media but also in mouse and human urine and we identified a novel CHZ metabolite, the CHZ-N-glucuronide (CHZ-N-Glc), which is resistant to enzymatic hydrolysis and produced independently of CHZ hydroxylation by CYP2E1. Moreover, we demonstrate that UGT1A1, 1A6 and 1A9 proteins catalyze the synthesis of CHZ-O-Glc while CHZ-N-Glc is produced by UGT1A9 specifically. Together, we demonstrated that hydrolysis of CHZ-O-Glc is required to reliably quantify CYP2E1 activity because of the rapid transformation of OH-CHZ into CHZ-O-Glc and identified the CHZ-N-Glc produced independently of the CYP2E1 activity. Our results also raise the questions of the contribution of CHZ-N-Glc in the overall CHZ metabolism and of the quantification of CHZ glucuronides in vitro and in vivo for measuring UGT1A activities.
Collapse
|
14
|
Le Guillou D, Bucher S, Begriche K, Hoët D, Lombès A, Labbe G, Fromenty B. Drug-Induced Alterations of Mitochondrial DNA Homeostasis in Steatotic and Nonsteatotic HepaRG Cells. J Pharmacol Exp Ther 2018; 365:711-726. [PMID: 29669730 DOI: 10.1124/jpet.117.246751] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Accepted: 04/06/2018] [Indexed: 12/19/2022] Open
Abstract
Although mitochondriotoxicity plays a major role in drug-induced hepatotoxicity, alteration of mitochondrial DNA (mtDNA) homeostasis has been described only with a few drugs. Because it requires long drug exposure, this mechanism of toxicity cannot be detected with investigations performed in isolated liver mitochondria or cultured cells exposed to drugs for several hours or a few days. Thus, a first aim of this study was to determine whether a 2-week treatment with nine hepatotoxic drugs could affect mtDNA homeostasis in HepaRG cells. Previous investigations with these drugs showed rapid toxicity on oxidative phosphorylation but did not address the possibility of delayed toxicity secondary to mtDNA homeostasis impairment. The maximal concentration used for each drug induced about 10% cytotoxicity. Two other drugs, zalcitabine and linezolid, were used as positive controls for their respective effects on mtDNA replication and translation. Another goal was to determine whether drug-induced mitochondriotoxicity could be modulated by lipid overload mimicking nonalcoholic fatty liver. Among the nine drugs, imipramine and ritonavir induced mitochondrial effects suggesting alteration of mtDNA translation. Ritonavir toxicity was stronger in nonsteatotic cells. None of the nine drugs decreased mtDNA levels. However, increased mtDNA was observed with five drugs, especially in nonsteatotic cells. The mtDNA levels could not be correlated with the expression of key factors involved in mitochondrial biogenesis, such as peroxisome proliferator-activated receptor-γ coactivator 1α (PGC1α), PGC1β, and AMP-activated protein kinase α-subunit. Hence, drug-induced impairment of mtDNA translation might not be rare, and increased mtDNA levels could be a frequent adaptive response to slight energy shortage. Nevertheless, this adaptation could be impaired by lipid overload.
Collapse
|
15
|
Bucher S, Tête A, Podechard N, Liamin M, Le Guillou D, Chevanne M, Coulouarn C, Imran M, Gallais I, Fernier M, Hamdaoui Q, Robin MA, Sergent O, Fromenty B, Lagadic-Gossmann D. Co-exposure to benzo[a]pyrene and ethanol induces a pathological progression of liver steatosis in vitro and in vivo. Sci Rep 2018; 8:5963. [PMID: 29654281 PMCID: PMC5899096 DOI: 10.1038/s41598-018-24403-1] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Accepted: 04/03/2018] [Indexed: 02/07/2023] Open
Abstract
Hepatic steatosis (i.e. lipid accumulation) and steatohepatitis have been related to diverse etiologic factors, including alcohol, obesity, environmental pollutants. However, no study has so far analyzed how these different factors might interplay regarding the progression of liver diseases. The impact of the co-exposure to the environmental carcinogen benzo[a]pyrene (B[a]P) and the lifestyle-related hepatotoxicant ethanol, was thus tested on in vitro models of steatosis (human HepaRG cell line; hybrid human/rat WIF-B9 cell line), and on an in vivo model (obese zebrafish larvae). Steatosis was induced prior to chronic treatments (14, 5 or 7 days for HepaRG, WIF-B9 or zebrafish, respectively). Toxicity and inflammation were analyzed in all models; the impact of steatosis and ethanol towards B[a]P metabolism was studied in HepaRG cells. Cytotoxicity and expression of inflammation markers upon co-exposure were increased in all steatotic models, compared to non steatotic counterparts. A change of B[a]P metabolism with a decrease in detoxification was detected in HepaRG cells under these conditions. A prior steatosis therefore enhanced the toxicity of B[a]P/ethanol co-exposure in vitro and in vivo; such a co-exposure might favor the appearance of a steatohepatitis-like state, with the development of inflammation. These deleterious effects could be partly explained by B[a]P metabolism alterations.
Collapse
|
16
|
Bucher S, Jalili P, Le Guillou D, Begriche K, Rondel K, Martinais S, Zalko D, Corlu A, Robin MA, Fromenty B. Bisphenol a induces steatosis in HepaRG cells using a model of perinatal exposure. ENVIRONMENTAL TOXICOLOGY 2017; 32:1024-1036. [PMID: 27322340 DOI: 10.1002/tox.22301] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Revised: 05/10/2016] [Accepted: 05/21/2016] [Indexed: 06/06/2023]
Abstract
Human exposure to bisphenol A (BPA) could favor obesity and related metabolic disorders such as hepatic steatosis. Investigations in rodents have shown that these deleterious effects are observed not only when BPA is administered during the adult life but also with different protocols of perinatal exposure. Whether perinatal BPA exposure could pose a risk in human is currently unknown, and thus appropriate in vitro models could be important to tackle this major issue. Accordingly, we determined whether long-term BPA treatment could induce steatosis in human HepaRG cells by using a protocol mimicking perinatal exposure. To this end, the kinetics of expression of seven proteins differentially expressed during liver development was determined during a 4-week period of cell culture required for proliferation and differentiation. By analogy with data reported in rodents and humans, our results indicated that the period of cell culture around day 15 and day 18 after seeding could be considered as the "natal" period. Consequently, HepaRG cells were treated for 3 weeks with BPA (from 0.2 to 2000 nM), with a treatment starting during the proliferating period. BPA was able to induce steatosis with a nonmonotonic dose response profile, with significant effects on neutral lipids and triglycerides observed for the 2 nM concentration. However, the expression of many enzymes involved in lipid and carbohydrate homeostasis was unchanged in exposed HepaRG cells. The expression of other potential BPA targets and enzymes involved in BPA biotransformation was also determined, giving answers as well as new questions regarding the mechanisms of action of BPA. Hence, HepaRG cells provide a valuable model that can prove useful for the toxicological assessment of endocrine disruptors on hepatic metabolisms, in particular in the developing liver. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1024-1036, 2017.
Collapse
|
17
|
Bucher S, Panjo H, Al-Salameh A, Bauduceau B, Benattar-Zibi L, Bertin P, Berrut G, Corruble E, Danchin N, Derumeaux G, Doucet J, Falissard B, Forette F, Hanon O, Ourabah R, Pasquier F, Piedvache C, Pinget M, Becquemont L, Ringa V. Relationship between achieved personalized glycaemic targets and monitoring of clinical events in elderly diabetic patients. DIABETES & METABOLISM 2017; 43:59-68. [PMID: 27316980 DOI: 10.1016/j.diabet.2016.05.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2015] [Revised: 04/29/2016] [Accepted: 05/14/2016] [Indexed: 06/06/2023]
Abstract
AIM Recent guidelines for the management of type 2 diabetes (T2DM) in the elderly recommend adjusting the therapeutic target (HbA1c) according to the patient's health. Our study aimed to explore the association between achieving the recommended personalized HbA1c target and the occurrence of major clinical events under real-life conditions. METHODS The T2DM S.AGES cohort was a prospective multicentre study into which 213 general practitioners recruited 983 non-institutionalized T2DM patients aged>65 years. The recommended personalized HbA1c targets were<7%, <8% and <9% for healthy, ill and very ill patients, respectively. Major clinical events (death from any cause, major vascular events and/or hospitalization) were recorded during the 3-year follow-up. Mixed-effects logistic regression models were used for the analyses. RESULTS Of the 747 patients analyzed at baseline, 551 (76.8%) were at their recommended personalized HbA1c target. During follow-up, 391 patients (52.3%) experienced a major clinical event. Of the patients who did not achieve their personalized HbA1c target (compared with those who did), the risk (OR) of a major clinical event was 0.95 (95% CI: 0.69-1.31; P=0.76). The risk of death, major vascular event and hospitalization were 0.88 (95% CI: 0.40-1.94; P=0.75), 1.14 (95% CI: 0.7-1.83; P=0.59) and 0.84 (95% CI: 0.60-1.18; P=0.32), respectively. CONCLUSION Over a 3-year follow-up period, our results showed no difference in risk of a major clinical event among patients, regardless of whether or not they achieved their personalized recommended HbA1c target. These results need to be confirmed before implementing a more permissive strategy for treating T2DM in elderly patients.
Collapse
|
18
|
Campana L, Testori A, Curatolo P, Quaglino P, Mocellin S, Framarini M, Borgognoni L, Ascierto P, Mozzillo N, Guida M, Bucher S, Rotunno R, Marenco F, De Salvo G, De Paoli A, Rossi C, Bonadies A. Treatment efficacy with electrochemotherapy: A multi-institutional prospective observational study on 376 patients with superficial tumors. Eur J Surg Oncol 2016; 42:1914-1923. [DOI: 10.1016/j.ejso.2016.06.399] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Revised: 06/17/2016] [Accepted: 06/21/2016] [Indexed: 12/21/2022] Open
|
19
|
Bucher S, Panjo H, Al-Salameh A, Bauduceau B, Benattar-Zibi L, Bertin P, Berrut G, Corruble E, Danchin N, Derumeaux G, Doucet J, Falissard B, Forette F, Hanon O, Ourabah R, Pasquier F, Piedvache C, Pinget M, Becquemont L, Ringa V. Atteinte de la cible thérapeutique personnalisée et la survenue d’événements cliniques chez des patients âgés diabétiques. Rev Epidemiol Sante Publique 2016. [DOI: 10.1016/j.respe.2016.10.033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
|
20
|
Guida M, Campana L, Curatolo P, Strippoli S, Bonadies A, Grilz G, Cabula C, Rotunno R, Bucher S, Solari N, Santoriello A, Valpione S, Rossi C. Local treatment with electrochemotherapy of superficial angiosarcomas: Efficacy and safety results from a multi-institutional retrospective study. Ann Oncol 2016. [DOI: 10.1093/annonc/mdw343.05] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
21
|
Michaut A, Le Guillou D, Moreau C, Bucher S, McGill MR, Martinais S, Gicquel T, Morel I, Robin MA, Jaeschke H, Fromenty B. A cellular model to study drug-induced liver injury in nonalcoholic fatty liver disease: Application to acetaminophen. Toxicol Appl Pharmacol 2015; 292:40-55. [PMID: 26739624 DOI: 10.1016/j.taap.2015.12.020] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Revised: 12/18/2015] [Accepted: 12/22/2015] [Indexed: 12/22/2022]
Abstract
Obesity and nonalcoholic fatty liver disease (NAFLD) can increase susceptibility to hepatotoxicity induced by some xenobiotics including drugs, but the involved mechanisms are poorly understood. For acetaminophen (APAP), a role of hepatic cytochrome P450 2E1 (CYP2E1) is suspected since the activity of this enzyme is consistently enhanced during NAFLD. The first aim of our study was to set up a cellular model of NAFLD characterized not only by triglyceride accumulation but also by higher CYP2E1 activity. To this end, human HepaRG cells were incubated for one week with stearic acid or oleic acid, in the presence of different concentrations of insulin. Although cellular triglycerides and the expression of lipid-responsive genes were similar with both fatty acids, CYP2E1 activity was significantly increased only by stearic acid. CYP2E1 activity was reduced by insulin and this effect was reproduced in cultured primary human hepatocytes. Next, APAP cytotoxicity was assessed in HepaRG cells with or without lipid accretion and CYP2E1 induction. Experiments with a large range of APAP concentrations showed that the loss of ATP and glutathione was almost always greater in the presence of stearic acid. In cells pretreated with the CYP2E1 inhibitor chlormethiazole, recovery of ATP was significantly higher in the presence of stearate with low (2.5mM) or high (20mM) concentrations of APAP. Levels of APAP-glucuronide were significantly enhanced by insulin. Hence, HepaRG cells can be used as a valuable model of NAFLD to unveil important metabolic and hormonal factors which can increase susceptibility to drug-induced hepatotoxicity.
Collapse
|
22
|
Mayati A, Le Vee M, Moreau A, Jouan E, Bucher S, Stieger B, Denizot C, Parmentier Y, Fardel O. Protein kinase C-dependent regulation of human hepatic drug transporter expression. Biochem Pharmacol 2015; 98:703-17. [PMID: 26462574 DOI: 10.1016/j.bcp.2015.10.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Accepted: 10/07/2015] [Indexed: 12/13/2022]
Abstract
Hepatic drug transporters are now recognized as major actors of hepatobiliary elimination of drugs. Characterization of their regulatory pathways is therefore an important issue. In this context, the present study was designed to analyze the potential regulation of human hepatic transporter expression by protein kinase C (PKC) activation. Treatment by the reference PKC activator phorbol 12-myristate 13-acetate (PMA) for 48h was shown to decrease mRNA expression of various sinusoidal transporters, including OATP1B1, OATP2B1, NTCP, OCT1 and MRP3, but to increase that of OATP1B3, whereas mRNA expression of canalicular transporters was transiently enhanced (MDR1), decreased (BSEP and MRP2) or unchanged (BCRP) in human hepatoma HepaRG cells. The profile of hepatic transporter mRNA expression changes in PMA-treated HepaRG cells was correlated to that found in PMA-exposed primary human hepatocytes and was similarly observed in response to the PKC-activating marketed drug ingenol mebutate. It was associated with concomitant repression of OATP1B1 and OATP2B1 protein expression and reduction of OATP, OCT1, NTCP and MRP2 activity. The use of chemical PKC inhibitors further suggested a contribution of novel PKCs isoforms to PMA-mediated regulations of transporter mRNA expression. PMA was finally shown to cause epithelial-mesenchymal transition (EMT) in HepaRG cells and exposure to various additional EMT inducers, i.e., hepatocyte growth factor, tumor growth factor-β1 or the HNF4α inhibitor BI6015, led to transporter expression alterations highly correlated to those triggered by PMA. Taken together, these data highlight PKC-dependent regulation of human hepatic drug transporter expression, which may be closely linked to EMT triggered by PKC activation.
Collapse
|
23
|
Baillieux A, Campisi D, Jammet N, Bucher S, Hunkeler D. Regional water quality patterns in an alluvial aquifer: direct and indirect influences of rivers. JOURNAL OF CONTAMINANT HYDROLOGY 2014; 169:123-131. [PMID: 25249478 DOI: 10.1016/j.jconhyd.2014.09.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Revised: 08/21/2014] [Accepted: 09/05/2014] [Indexed: 06/03/2023]
Abstract
The influence of rivers on the groundwater quality in alluvial aquifers can be twofold: direct and indirect. Rivers can have a direct influence via recharge and an indirect one by controlling the distribution of fine-grained, organic-carbon rich flood deposits that induce reducing conditions. These direct and indirect influences were quantified for a large alluvial aquifer on the Swiss Plateau (50km(2)) in interaction with an Alpine river using nitrate as an example. The hydrochemistry and stable isotope composition of water were characterized using a network of 115 piezometers and pumping stations covering the entire aquifer. Aquifer properties, land use and recharge zones were evaluated as well. This information provided detailed insight into the factors that control the spatial variability of groundwater quality. Three main factors were identified: (1) diffuse agricultural pollution sources; (2) dilution processes resulting from river water infiltrations, revealed by the δ(18)OH2O and δ(2)HH2O contents of groundwater; and (3) denitrification processes, controlled by the spatial variability of flood deposits governed by fluvial depositional processes. It was possible to quantify the dependence of the nitrate concentration on these three factors at any sampling point of the aquifer using an end-member mixing model, where the average nitrate concentration in recharge from the agricultural area was evaluated at 52mg/L, and the nitrate concentration of infiltrating river at approximately 6mg/L. The study shows the importance of considering the indirect and direct impacts of rivers on alluvial aquifers and provides a methodological framework to evaluate aquifer scale water quality patterns.
Collapse
|
24
|
Quesnot N, Bucher S, Fromenty B, Robin MA. Modulation of metabolizing enzymes by bisphenol a in human and animal models. Chem Res Toxicol 2014; 27:1463-73. [PMID: 25142872 DOI: 10.1021/tx500087p] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Xenobiotics, such as contaminants and drugs, can be converted to potentially toxic reactive metabolites by phase 1 oxidizing enzymes. These metabolites are further detoxified by phase 2 conjugating enzymes and eliminated from cells by phase 3 transporters. Moreover, many of these xenobiotics are also able to induce or inhibit these enzymes, potentially modulating their own toxicity or that of other chemicals. The present review is focused on bisphenol A, a synthetic monomer used for many industrial applications and exhibiting xenoestrogen properties. The impact of this contaminant on all major classes of metabolizing enzymes (i.e., cytochromes P450, glutathione-S-transferases, sulfotransferases, UDP-glucuronyltransferases, and transporters) was reviewed, with a highlight on the modulation of cytochromes P450 involved in steroid metabolism. Interestingly, most of the studies reported in this review show that BPA is able to induce or inhibit metabolizing enzymes at high doses but also at doses compatible with human exposure.
Collapse
|
25
|
Bucher S, Le Vee M, Jouan E, Fardel O. Regulation of hepatic drug transporter activity and expression by organochlorine pesticides. J Biochem Mol Toxicol 2013; 28:119-28. [PMID: 24464585 DOI: 10.1002/jbt.21543] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2013] [Revised: 10/31/2013] [Accepted: 11/01/2013] [Indexed: 12/18/2022]
Abstract
Organochlorine (OC) pesticides constitute a major class of persistent and toxic organic pollutants, known to modulate drug-detoxifying enzymes. In the present study, OCs were demonstrated to also alter the activity and expression of human hepatic drug transporters. Activity of the sinusoidal influx transporter OCT1 (organic cation transporter 1) was thus inhibited by endosulfan, chlordane, heptachlor, lindane, and dieldrine, but not by dichlorodiphenyltrichloroethane isomers, whereas those of the canalicular efflux pumps MRP2 (multidrug resistance-associated protein 2) and BCRP (breast cancer resistance protein) were blocked by endosulfan, chlordane, heptachlor, and chlordecone; this latter OC additionally inhibited the multidrug resistance gene 1 (MDR1)/P-glycoprotein (P-gp) activity. OCs, except endosulfan, were next found to induce MDR1/P-gp and MRP2 mRNA expressions in hepatoma HepaRG cells; some of them also upregulated BCRP. By contrast, expression of sinusoidal transporters was not impaired (organic anion-transporting polypeptide (OATP) 1B1 and OATP2B1) or was downregulated (sodium taurocholate co-transporting polypeptide (NTCP) and OCT1). Such regulations of drug transporter activity and expression, depending on the respective nature of OCs and transporters, may contribute to the toxicity of OC pesticides.
Collapse
|