1
|
Serafín-Fabian JI, Elena Moreno-Godínez M, Flores-Alfaro E, Parra-Rojas I, Rojas-García AE, Campos-Viguri GE, Cahua-Pablo JÁ, Ramírez-Vargas MA. β-glucuronidase as a biomarker for assessing the exposure to anticholinergic pesticides: A meta-analysis. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2023; 103:104279. [PMID: 37741477 DOI: 10.1016/j.etap.2023.104279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 07/21/2023] [Accepted: 09/19/2023] [Indexed: 09/25/2023]
Abstract
INTRODUCTION The human exposure to anticholinergic pesticides has been associated with the development of various diseases. Therefore, several biomarkers have been proposed for biomonitoring human exposure to anticholinergic pesticides. OBJECTIVE This work evaluated the effect of human exposure to anticholinergic pesticides on β-glucuronidase (GUSB) levels. METHODS A systematic review was performed using PubMed, Web of Science, Scopus, and EBSCO databases up to December 2021. The statistical analysis employed standardized mean differences and meta-regression. And the trial sequential analysis was performed. RESULTS Nine studies were included. A monotonic relationship was observed between poisoning severity and GUSB. Furthermore, BuChE levels were correlated with GUSB levels. CONCLUSIONS The results indicated that GUSB levels could be used as a possible diagnosis biomarker in poisoning related to anticholinergic pesticide exposure. However, the use of GUSB to assess the chronic exposure to anticholinergic pesticides could be only performed in recent exposure (≈ 7 days after last exposure).
Collapse
Affiliation(s)
- Jesús Isimar Serafín-Fabian
- Facultad de Ciencias Químico-Biológicas, Laboratorio de Epidemiología Clínica y Molecular, Universidad Autónoma De Guerrero, Guerrero, Mexico
| | - Ma Elena Moreno-Godínez
- Facultad de Ciencias Químico-Biológicas, Laboratorio de Toxicología y Salud Ambiental, Universidad Autónoma De Guerrero, Guerrero, Mexico
| | - Eugenia Flores-Alfaro
- Facultad de Ciencias Químico-Biológicas, Laboratorio de Epidemiología Clínica y Molecular, Universidad Autónoma De Guerrero, Guerrero, Mexico
| | - Isela Parra-Rojas
- Facultad de Ciencias Químico-Biológicas, Laboratorio de Investigación en Obesidad y Diabetes, Universidad Autónoma De Guerrero, Guerrero, Mexico
| | - Aurora Elizabeth Rojas-García
- Secretaría de Investigación y Posgrado, Laboratorio de Contaminación y Toxicología Ambiental, Universidad Autónoma de Nayarit, Nayarit, Mexico
| | | | - José Ángel Cahua-Pablo
- Facultad de Ciencias Químico-Biológicas, Laboratorio de Epidemiología Clínica y Molecular, Universidad Autónoma De Guerrero, Guerrero, Mexico
| | - Marco Antonio Ramírez-Vargas
- Facultad de Ciencias Químico-Biológicas, Laboratorio de Toxicología y Salud Ambiental, Universidad Autónoma De Guerrero, Guerrero, Mexico.
| |
Collapse
|
2
|
Sepahi S, Gerayli S, Delirrad M, Taghavizadeh Yazdi ME, Zare-Zardini H, Bushehri B, Ghorani-Azam A. Biochemical responses as early and reliable biomarkers of organophosphate and carbamate pesticides intoxication: A systematic literature review. J Biochem Mol Toxicol 2023; 37:e23285. [PMID: 36524544 DOI: 10.1002/jbt.23285] [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: 07/23/2022] [Revised: 11/03/2022] [Accepted: 12/09/2022] [Indexed: 12/23/2022]
Abstract
Inhibition of cholinesterase (ChE) activity has been long considered as the main diagnostic method of organophosphate (OP) and carbamate pesticides poisoning; however, it has been shown that ChE activity may also be altered due to exposure to other non-organophosphorus toxicants and variety of different medical conditions. Hence, to avoid misdiagnosis, we aimed to systematically review available documents to look for additional biomarkers of OP and carbamate poisoning. The electronic databases in addition to Google scholar were searched for eligible articles on March 2022 using "organophosphate," "carbamate," and "biomarker" including all their similar terms. After collecting the relevant documents, the data were extracted and described qualitatively. In total, data of 66 articles from 51 human and 15 animal studies were extracted. Findings demonstrated that enzymes such as β-glucuronidase, neuropathy target esterase, amylase, and lipase, in addition to hematological indicators such as CBC, CRP, lactate dehydrogenase, and CPK have high sensitivity and accuracy in the diagnosis of OP poisoning. Findings suggest that using various markers for diagnosis of OP intoxication is helpful for appropriate management, and early identifying the patients at risk of death. The suggested biomarkers also help to avoid misdiagnosis of OP poisoning with other similar conditions.
Collapse
Affiliation(s)
- Samaneh Sepahi
- Food and Beverages Safety Research Center, Urmia University of Medical Sciences, Urmia, Iran
| | - Sina Gerayli
- Division of Inflammation and inflammatory Diseases, Immunology Research Center, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Mohammad Delirrad
- Food and Beverages Safety Research Center, Urmia University of Medical Sciences, Urmia, Iran.,Department of Forensic Medicine and Toxicology, Urmia University of Medical Sciences, Urmia, Iran
| | | | - Hadi Zare-Zardini
- Hematology and Oncology Research Center, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.,Department of Sciences, Farhangian University, Isfahan, Iran
| | - Behzad Bushehri
- Department of Forensic Medicine and Toxicology, Urmia University of Medical Sciences, Urmia, Iran
| | - Adel Ghorani-Azam
- Food and Beverages Safety Research Center, Urmia University of Medical Sciences, Urmia, Iran.,Department of Forensic Medicine and Toxicology, Urmia University of Medical Sciences, Urmia, Iran
| |
Collapse
|
3
|
Herrera-Moreno JF, Medina-Díaz IM, Bernal-Hernández YY, Barrón-Vivanco BS, González-Arias CA, Moreno-Godínez ME, Verdín-Betancourt FA, Sierra-Santoyo A, Rojas-García AE. Organophosphorus pesticide exposure biomarkers in a Mexican population. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:50825-50834. [PMID: 33970420 DOI: 10.1007/s11356-021-14270-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Accepted: 04/30/2021] [Indexed: 06/12/2023]
Abstract
The organophosphate (OP) pesticides are neurotoxic compounds widely used around the world. Evaluation of OP exposure in human studies is important for enabling adequate data analyses and drawing accurate conclusions. The aim of this study was to analyze OP exposure biomarkers and their relationships in a Mexican population with different exposure levels. Dialkylphosphates (DAP) were determined through gas chromatography-mass spectrometry (GC-MSD); acetylcholinesterase (AChE), butyrylcholinesterase (BuChE), arylesterase (AREase), basal paraoxonase 1 (PONase), and β-glucuronidase activities were detected using spectrophotometric methods. The albumin content was determined in a certified clinical laboratory. The DMTP metabolite was found in the highest concentration, and a negative and significant correlation between DAP and cholinesterase activity was observed. Our results suggested that BuChE is a considerably more sensitive biomarker than AChE. In addition, β-glucuronidase was positively correlated with albumin, BuChE, and PONase. In conclusion, our data strongly support the use of two or more biomarkers of exposure in human monitoring and the application of a strong and validated questionnaire.
Collapse
Affiliation(s)
- José Francisco Herrera-Moreno
- Laboratorio de Contaminación y Toxicología Ambiental, Secretaría de Investigación y Posgrado, Universidad Autónoma de Nayarit, Tepic, Nayarit, Mexico
| | - Irma Martha Medina-Díaz
- Laboratorio de Contaminación y Toxicología Ambiental, Secretaría de Investigación y Posgrado, Universidad Autónoma de Nayarit, Tepic, Nayarit, Mexico
| | - Yael Yvette Bernal-Hernández
- Laboratorio de Contaminación y Toxicología Ambiental, Secretaría de Investigación y Posgrado, Universidad Autónoma de Nayarit, Tepic, Nayarit, Mexico
| | - Briscia Socorro Barrón-Vivanco
- Laboratorio de Contaminación y Toxicología Ambiental, Secretaría de Investigación y Posgrado, Universidad Autónoma de Nayarit, Tepic, Nayarit, Mexico
| | - Cyndia Azucena González-Arias
- Laboratorio de Contaminación y Toxicología Ambiental, Secretaría de Investigación y Posgrado, Universidad Autónoma de Nayarit, Tepic, Nayarit, Mexico
| | - Ma Elena Moreno-Godínez
- Laboratorio de Toxicología y Salud Ambiental. Facultad de Ciencias Químico-Biológicas, Universidad Autónoma de Guerrero, Chilpancingo, Guerrero, Mexico
| | - Francisco Alberto Verdín-Betancourt
- Laboratorio de Contaminación y Toxicología Ambiental, Secretaría de Investigación y Posgrado, Universidad Autónoma de Nayarit, Tepic, Nayarit, Mexico
| | - Adolfo Sierra-Santoyo
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del IPN, Mexico City, Mexico
| | - Aurora Elizabeth Rojas-García
- Laboratorio de Contaminación y Toxicología Ambiental, Secretaría de Investigación y Posgrado, Universidad Autónoma de Nayarit, Tepic, Nayarit, Mexico.
| |
Collapse
|
4
|
Awolade P, Cele N, Kerru N, Gummidi L, Oluwakemi E, Singh P. Therapeutic significance of β-glucuronidase activity and its inhibitors: A review. Eur J Med Chem 2020; 187:111921. [PMID: 31835168 PMCID: PMC7111419 DOI: 10.1016/j.ejmech.2019.111921] [Citation(s) in RCA: 65] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Revised: 11/27/2019] [Accepted: 11/27/2019] [Indexed: 01/02/2023]
Abstract
The emergence of disease and dearth of effective pharmacological agents on most therapeutic fronts, constitutes a major threat to global public health and man's existence. Consequently, this has created an exigency in the search for new drugs with improved clinical utility or means of potentiating available ones. To this end, accumulating empirical evidence supports molecular target therapy as a plausible egress and, β-glucuronidase (βGLU) - a lysosomal acid hydrolase responsible for the catalytic deconjugation of β-d-glucuronides has emerged as a viable molecular target for several therapeutic applications. The enzyme's activity level in body fluids is also deemed a potential biomarker for the diagnosis of some pathological conditions. Moreover, due to its role in colon carcinogenesis and certain drug-induced dose-limiting toxicities, the development of potent inhibitors of βGLU in human intestinal microbiota has aroused increased attention over the years. Nevertheless, although our literature survey revealed both natural products and synthetic scaffolds as potential inhibitors of the enzyme, only few of these have found clinical utility, albeit with moderate to poor pharmacokinetic profile. Hence, in this review we present a compendium of exploits in the present millennium directed towards the inhibition of βGLU. The aim is to proffer a platform on which new scaffolds can be modelled for improved βGLU inhibitory potency and the development of new therapeutic agents in consequential.
Collapse
Affiliation(s)
- Paul Awolade
- School of Chemistry and Physics, University of KwaZulu-Natal, P/Bag X54001, Westville, Durban, South Africa
| | - Nosipho Cele
- School of Chemistry and Physics, University of KwaZulu-Natal, P/Bag X54001, Westville, Durban, South Africa
| | - Nagaraju Kerru
- School of Chemistry and Physics, University of KwaZulu-Natal, P/Bag X54001, Westville, Durban, South Africa
| | - Lalitha Gummidi
- School of Chemistry and Physics, University of KwaZulu-Natal, P/Bag X54001, Westville, Durban, South Africa
| | - Ebenezer Oluwakemi
- School of Chemistry and Physics, University of KwaZulu-Natal, P/Bag X54001, Westville, Durban, South Africa
| | - Parvesh Singh
- School of Chemistry and Physics, University of KwaZulu-Natal, P/Bag X54001, Westville, Durban, South Africa.
| |
Collapse
|
5
|
β-Glucuronidase and Its Relationship With Clinical Parameters and Biomarkers of Pesticide Exposure. J Occup Environ Med 2018; 60:e602-e609. [DOI: 10.1097/jom.0000000000001460] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
6
|
Beltagy DM, Sadek KM, Hafez AS. Serum β-glucuronidase activity as a biomarker for acute cholinesterase inhibitor pesticide poisoning. Toxicol Ind Health 2018; 34:891-897. [PMID: 30352546 DOI: 10.1177/0748233718802068] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
β-glucuronidase (BG) activity is a promising biomarker for diagnosis and prognosis after exposure to organophosphorous (OP) pesticides. The aim of this study was to evaluate the changes in serum BG activity in patients with acute OP poisoning and to determine whether these changes correlate with the severity of poisoning. Thirty patients with anticholinesterase pesticide poisoning were included, besides 10 healthy volunteers as a control group. Serum activities of butyrylcholinesterase (BuChE) and BG were measured for each subject on admission, then after 12 and 24 h. Serum levels of BuChE and BG in poisoned patients were significantly different from the control subjects; these differences persisted in repeated measurements. Moreover, the serum levels showed significant differences within each group of the three time points. A significant negative correlation was found between the serum activities of BuChE and BG in all groups at the three time points. In conclusion, serum BG activity seems a reliable marker for OP poisoning even when measured at 24 h after poisoning.
Collapse
Affiliation(s)
- Doha M Beltagy
- Biochemistry division, Department of Chemistry, Faculty of Science, Damanhour University, Damanhour, Egypt
| | - Kadry M Sadek
- Department of Biochemistry, Faculty of Veterinary Medicine, Damanhur University, Damanhour, Egypt
| | - Amal S Hafez
- Department of Forensic Medicine and Clinical Toxicology, Faculty of Medicine, Tanta University, Tanta, Egypt
| |
Collapse
|
7
|
Soltaninejad K, Shadnia S, Afkhami-Taghipour M, Saljooghi R, Mohammadirad A, Abdollahi M. Blood β-glucuronidase as a suitable biomarker at acute exposure of severe organophosphorus poisoning in human. Hum Exp Toxicol 2016; 26:963-6. [DOI: 10.1177/0960327107085349] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Organophosphorus compounds are known to cause the selective release of liver microsomal β-glucuronidase into plasma. Organophophoruses may induce nitrosative stress leading to the generation of nitrogen free radicals and alterations in scavengers of free radicals in many biological systems. In this study, we investigate how acute human organophosphorus intoxication is associated with changes of blood nitric oxide, total thiol molecules, and activities of the acetylcholinesterase and β-glucuronidase. A total of 21 acute organophosphorus-poisoned patients were recruited into study and were divided into two groups of mildly (13) and severely affected (9); 26 age-matched healthy volunteers were recruited as control group. Results indicated that both mildly and severely affected patients had lower acetylcholinesterase activities as compared to controls. The extent of acetylcholinesterase reduction in the severely affected patients was higher than that of mildly affected patients. A significant increase in serum β-glucuronidase was observed only in severely affected patients as compared to controls. Both mildly and severely affected patients had lower plasma total thiol molecules as compared to controls. The extent of reduction of total thiol molecules in the severely affected patients was higher than that of mildly affected patients. No significant difference was observed in plasma total nitric oxide of controls and patients. It is concluded that nitrosative stress has a minor role in toxicity of organophosphorus, whereas blood β-glucuronidase is very sensitive biomarker at high exposure of severe organophosphorus poisoning.
Collapse
Affiliation(s)
- K Soltaninejad
- Laboratory of Forensic Toxicology, Legal Medicine Organization, Tehran, Iran
| | - S Shadnia
- Toxicological Research Center, Loqman-Hakim Hospital, School of Medicine, Shaheed Beheshti University of Medical Sciences, Tehran, Iran
| | - M Afkhami-Taghipour
- Laboratory of Toxicology, Faculty of Phamacy, and Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences, Tehran, Iran
| | - R Saljooghi
- Laboratory of Toxicology, Faculty of Phamacy, and Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences, Tehran, Iran
| | - A Mohammadirad
- Laboratory of Toxicology, Faculty of Phamacy, and Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences, Tehran, Iran
| | - M Abdollahi
- Laboratory of Toxicology, Faculty of Phamacy, and Pharmaceutical Sciences Research Center, Tehran University of Medical Sciences, Tehran, Iran
| |
Collapse
|
8
|
β-Glucuronidase activity is a sensitive biomarker to assess low-level organophosphorus insecticide exposure. Toxicol Lett 2010; 193:115-9. [DOI: 10.1016/j.toxlet.2009.12.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2009] [Revised: 12/11/2009] [Accepted: 12/11/2009] [Indexed: 11/18/2022]
|
9
|
Shi D, Yang J, Yang D, Yan B. Dexamethasone suppresses the expression of multiple rat carboxylesterases through transcriptional repression: evidence for an involvement of the glucocorticoid receptor. Toxicology 2008; 254:97-105. [PMID: 18938207 DOI: 10.1016/j.tox.2008.09.019] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2008] [Revised: 09/15/2008] [Accepted: 09/19/2008] [Indexed: 01/28/2023]
Abstract
Carboxylesterases play important roles in the metabolism of xenobiotics and detoxication of insecticides. Without exception, all mammalian species studied express multiple forms of carboxylesterases. Several rat carboxylesterases are well-characterized including hydrolase A, B and S, and the expression of these enzymes is significantly suppressed by glucocorticoid dexamethasone. In this study, we used multiple experimental systems and presented a molecular mechanism for the suppression. Rats receiving one or more daily injections of dexamethasone consistently expressed lower HA, HB and HS. The suppression occurred at the levels of mRNA, protein and hydrolytic activity. In hepatoma cell line H4-II-E-C3, nanomolar dexamethasone caused significant decreases in HA, HB and HS mRNA, and the decreases were abolished by antiglucocorticoid RU486. Additionally, dexamethasone at nanomolar concentrations repressed the promoters of carboxylesterases, and the repression was reduced by glucocorticoid receptor-beta, a dominant negative regulator of the glucocorticoid receptor (GR). In contrast, co-transfection of the pregnane X receptor (PXR) increased the reporter activities, but the increase occurred only at micromolar concentrations of dexamethasone. These findings establish that both GR and PXR are involved in the regulated expression of rat carboxylesterases by dexamethasone but their involvement depends on the concentrations.
Collapse
Affiliation(s)
- Deshi Shi
- Department of Biomedical Sciences, Center for Pharmacogenomics and Molecular Therapy, University of Rhode Island, Kingston, RI 02881, United States
| | | | | | | |
Collapse
|
10
|
Inayat-Hussain SH, Lubis SH, Sakian NIM, Ghazali AR, Ali NS, el Sersi M, Toong LM, Zainal AM, Hashim S, Ghazali MS, Saidin MN, Rahman ARA, Rafaai MJM, Omar S, Rapiai R, Othman R, Chan LT, Johari A, Soon WH, Salleh AR, Satoh T. Is plasma β-glucuronidase a novel human biomarker for monitoring anticholinesterase pesticides exposure? A Malaysian experience. Toxicol Appl Pharmacol 2007; 219:210-6. [DOI: 10.1016/j.taap.2006.10.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2006] [Revised: 10/16/2006] [Accepted: 10/17/2006] [Indexed: 10/24/2022]
|
11
|
Furlong CE. Genetic variability in the cytochrome P450–paraoxonase 1 (PON1) pathway for detoxication of organophosphorus compounds. J Biochem Mol Toxicol 2007; 21:197-205. [DOI: 10.1002/jbt.20181] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
12
|
Satoh T, Hosokawa M. Structure, function and regulation of carboxylesterases. Chem Biol Interact 2006; 162:195-211. [PMID: 16919614 DOI: 10.1016/j.cbi.2006.07.001] [Citation(s) in RCA: 354] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2006] [Revised: 06/14/2006] [Accepted: 07/01/2006] [Indexed: 11/22/2022]
Abstract
This review covers current developments in molecular-based studies of the structure and function of carboxylesterases. To allay the confusion of the classic classification of carboxylesterase isozymes, we have proposed a novel nomenclature and classification of mammalian carboxylesterases on the basis of molecular properties. In addition, mechanisms of regulation of gene expression of carboxylesterases by xenobiotics and involvement of carboxylesterase in drug metabolism and enzyme induction are also described.
Collapse
Affiliation(s)
- Tetsuo Satoh
- Graduate School of Pharmaceutical Sciences, Chiba University, Japan.
| | | |
Collapse
|
13
|
Anand SS, Bruckner JV, Haines WT, Muralidhara S, Fisher JW, Padilla S. Characterization of deltamethrin metabolism by rat plasma and liver microsomes. Toxicol Appl Pharmacol 2005; 212:156-66. [PMID: 16169030 DOI: 10.1016/j.taap.2005.07.021] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2005] [Revised: 07/15/2005] [Accepted: 07/18/2005] [Indexed: 11/15/2022]
Abstract
Deltamethrin, a widely used type II pyrethroid insecticide, is a relatively potent neurotoxicant. While the toxicity has been extensively examined, toxicokinetic studies of deltamethrin and most other pyrethroids are very limited. The aims of this study were to identify, characterize, and assess the relative contributions of esterases and cytochrome P450s (CYP450s) responsible for deltamethrin metabolism by measuring deltamethrin disappearance following incubation of various concentrations (2 to 400 microM) in plasma (esterases) and liver microsomes (esterases and CYP450s) prepared from adult male rats. While the carboxylesterase metabolism in plasma and liver was characterized using an inhibitor, tetra isopropyl pyrophosphoramide (isoOMPA), CYP450 metabolism was characterized using the cofactor, NADPH. Michaelis-Menten rate constants were calculated using linear and nonlinear regression as applicable. The metabolic efficiency of these pathways was estimated by calculating intrinsic clearance (Vmax/Km). In plasma, isoOMPA completely inhibited deltamethrin biotransformation at concentrations (2 and 20 microM of deltamethrin) that are 2- to 10-fold higher than previously reported peak blood levels in deltamethrin-poisoned rats. For carboxylesterase-mediated deltamethrin metabolism in plasma, Vmax=325.3+/-53.4 nmol/h/ml and Km=165.4+/-41.9 microM. Calcium chelation by EGTA did not inhibit deltamethrin metabolism in plasma or liver microsomes, indicating that A-esterases do not metabolize deltamethrin. In liver microsomes, esterase-mediated deltamethrin metabolism was completely inhibited by isoOMPA, confirming the role of carboxylesterases. The rate constants for liver carboxylesterases were Vmax=1981.8+/-132.3 nmol/h/g liver and Km=172.5+/-22.5 microM. Liver microsomal CYP450-mediated biotransformation of deltamethrin was a higher capacity (Vmax=2611.3+/-134.1 nmol/h/g liver) and higher affinity (Km=74.9+/-5.9 microM) process than carboxylesterase (plasma or liver) detoxification. Genetically engineered individual rat CYP450s (Supersomes) were used to identify specific CYP450 isozyme(s) involved in the deltamethrin metabolism. CYP1A2, CYP1A1, and CYP2C11 in decreasing order of importance quantitatively, metabolized deltamethrin. Intrinsic clearance by liver CYP450s (35.5) was more efficient than that by liver (12.0) or plasma carboxylesterases (2.4).
Collapse
Affiliation(s)
- Sathanandam S Anand
- Department of Pharmaceutical and Biomedical Sciences, College of Pharmacy, University of Georgia, Athens, GA 30602, USA.
| | | | | | | | | | | |
Collapse
|
14
|
Hernández A, Gómez MA, Pena G, Gil F, Rodrigo L, Villanueva E, Pla A. Effect of long-term exposure to pesticides on plasma esterases from plastic greenhouse workers. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2004; 67:1095-1108. [PMID: 15205026 DOI: 10.1080/15287390490452371] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Previous reports in animals considered beta-glucuronidase activity as a novel biomarker of anticholinesterase (organophosphates and carbamates) pesticides exposure. Acid phosphatase activity was also shown to increase after organophosphates exposure. In addition, there is evidence that the paraoxonase status influences sensitivity to specific pesticides. In this study, activities of beta-glucuronidase, acid phosphatase, cholinesterase, and paraoxonase were measured in plasma from plastic greenhouse workers exposed over the long term to different pesticides, including organophosphates and carbamates, in order to evaluate the potential chronic toxicity of pesticides at occupational level. Our results show that activities of paraoxonase and cholinesterase were decreased in applicators of pesticides compared to non-applicators. Likewise, it was found that activities of beta-glucuronidase and acid phosphatase were associated with pesticide exposure in humans, and that both biochemical parameters were related to each other. Interestingly, the paraoxonase B allele (phenotyped in plasma) was associated with a higher risk of inhibition of cholinesterase activity above a 25% level, which supports the hypothesis that paraoxonase phenotypes are associated with susceptibility of humans to anticholinesterase pesticides toxicity.
Collapse
Affiliation(s)
- Antonio Hernández
- Department of Legal Medicine and Toxicology, University of Granada School of Medicine, Granada, Spain.
| | | | | | | | | | | | | |
Collapse
|
15
|
Abstract
Biological markers (biomarkers) are used to recognize, characterize and monitor treatment-related responses following exposure to xenobiotics. Biomarkers serve three primary applications in toxicology: 1) to confirm exposure to a deleterious agent, 2) to provide a system for monitoring individual susceptibility to a toxicant, and 3) to quantitatively assess deleterious effects of a toxicant to an organism or individual. Because the liver is a general target for adverse effects of drugs and other chemicals, biomarkers of untoward hepatic response to xenobiotics are of particular interest to the pharmaceutical toxicologist. General requirements for the latter category of biomarkers are sample availability, target organ specificity, sensitivity for the toxicity of interest, accessibility, a relatively short half-life, and available detection systems. Biomarkers that can be assayed in biological fluids from both human and animal subjects are particularly desirable. Histologically, acute and subacute hepatic toxicity commonly involves necrosis, steatosis, cholestasis, vascular disorders, or multiple lesions. The purpose of this review is to summarize reported applications using clinical analytes and biochemical indicators of hepatic dysfunction with emphasis on those that show promise of supplementing or improving upon standard laboratory procedures. Liver function markers refer to peripheral indicators of hepatic synthetic and secretory activities, enterohepatic function, or perturbations of the hepatic uptake and clearance of circulating biomolecules. Liver injury biomarkers include various peripheral proteins released in response to a cellular damage or locally, proteins that are significantly altered within the liver. These include both circulating cytosolic, mitochondrial, or canalicular membrane markers, and the up-regulation or depletion of radical scavengers, modulators, and stabilizers of intracellular damage. Subsequent recovery from a toxic insult involves repair, regenerative, and proliferative responses that constitute the third class of biomarkers. Of these, protein markers found either in sera, plasma, or urine either during or just prior to the early manifestation of histological hepatic lesions are of greatest interest. Examples of a number of these markers, their documented applications in humans or animals, and potential advantages as well as limitations are presented.
Collapse
Affiliation(s)
- D E Amacher
- Drug Safety Evaluation, Pfizer Global Research and Development, Groton, Connecticut 06340, USA.
| |
Collapse
|