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In vivo studies on inhibition and recovery of B-esterase activities in Biomphalaria glabrata exposed to azinphos-methyl: Analysis of enzyme, substrate and tissue dependence

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Název: In vivo studies on inhibition and recovery of B-esterase activities in Biomphalaria glabrata exposed to azinphos-methyl: Analysis of enzyme, substrate and tissue dependence
Autoři: Kristoff, G., Chiny Barrionuevo, D., Cacciatore, L.C., Verrengia Guerrero, N.R., Cochón, A.C.
Sbírka: Biblioteca Digital FCEN-UBA (Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires)
Témata: Azinphos-methyl, Biomphalaria glabrata, Carboxylesterases, Cholinesterases, Freshwater invertebrate, Pesticides, 1 naphthyl acetate, 2 naphthyl acetate, 4 nitrophenyl acetate, acetic acid derivative, acetylthiocholine, azinphos methyl, butyric acid 4 nitrophenyl ester, butyric acid derivative, butyrylthiocholine, carboxylesterase, choline derivative, cholinesterase, propionylthiocholine, unclassified drug, bioaccumulation, biomarker, carbamate (ester), enzyme activity, inhibition, insecticide, organophosphate, pollution exposure, snail, substrate
Popis: Cholinesterases and carboxylesterases belong to the group of B-esterases, the serine superfamily of esterases that are inhibited by organophosphorus compounds. It is now generally accepted that before using the B-esterases as biomarkers of exposure to organophosphorus and carbamates in a given species, the biochemical characteristics of these enzymes should be carefully studied. In this study, the enzyme/s and the tissue/s to be selected as sensitive biomarkers of organophosphorus exposition in the freshwater gastropod Biomphalaria glabrata were investigated. Firstly, the substrate dependence of cholinesterase and carboxylesterase activities in whole organism soft tissue and in different tissues of the snail (head-foot, pulmonary region, digestive gland, and gonads) was analyzed. Measurements of cholinesterase activity were performed using three substrates: acetylthiocholine (AcSCh), propionylthiocholine (PrSCh), and butyrylthiocholine (BuSCh). Carboxylesterase activity was determined using four different substrates: 1-naphthyl acetate (1-NA), 2-naphthyl acetate (2-NA), p-nitrophenyl acetate (p-NPA), and p-nitrophenyl butyrate (p-NPB). Regardless of the tissue analyzed, the highest specific activity was obtained when using AcSCh, followed by PrSCh. Cholinesterase activity measured with BuSCh was very low in all cases. On the other hand, the highest cholinesterase activity was measured in head-foot and in pulmonary region, representing in the case of AcSCh hydrolysis 196% and 180% of the activity measured in whole organism soft tissue, respectively. In contrast, AcSCh hydrolysis in digestive gland and gonads was 28% and 50% of that measured in whole organism soft tissue. Regarding carboxylesterase activity, although all tissues hydrolyzed the four substrates assayed, substrate preferences varied among tissues. In particular, digestive glands showed higher carboxylesterase activity than the other tissues (299%, 359% and 137% of whole organism soft tissue activity) when measured with 1-NA, 2-NA and p-NPA as ...
Druh dokumentu: journal/newspaper
Jazyk: unknown
Dostupnost: https://hdl.handle.net/20.500.12110/paper_0166445X_v112-113_n_p19_Kristoff
Rights: info:eu-repo/semantics/openAccess ; http://creativecommons.org/licenses/by/2.5/ar
Přístupové číslo: edsbas.82820712
Databáze: BASE
Popis
Abstrakt:Cholinesterases and carboxylesterases belong to the group of B-esterases, the serine superfamily of esterases that are inhibited by organophosphorus compounds. It is now generally accepted that before using the B-esterases as biomarkers of exposure to organophosphorus and carbamates in a given species, the biochemical characteristics of these enzymes should be carefully studied. In this study, the enzyme/s and the tissue/s to be selected as sensitive biomarkers of organophosphorus exposition in the freshwater gastropod Biomphalaria glabrata were investigated. Firstly, the substrate dependence of cholinesterase and carboxylesterase activities in whole organism soft tissue and in different tissues of the snail (head-foot, pulmonary region, digestive gland, and gonads) was analyzed. Measurements of cholinesterase activity were performed using three substrates: acetylthiocholine (AcSCh), propionylthiocholine (PrSCh), and butyrylthiocholine (BuSCh). Carboxylesterase activity was determined using four different substrates: 1-naphthyl acetate (1-NA), 2-naphthyl acetate (2-NA), p-nitrophenyl acetate (p-NPA), and p-nitrophenyl butyrate (p-NPB). Regardless of the tissue analyzed, the highest specific activity was obtained when using AcSCh, followed by PrSCh. Cholinesterase activity measured with BuSCh was very low in all cases. On the other hand, the highest cholinesterase activity was measured in head-foot and in pulmonary region, representing in the case of AcSCh hydrolysis 196% and 180% of the activity measured in whole organism soft tissue, respectively. In contrast, AcSCh hydrolysis in digestive gland and gonads was 28% and 50% of that measured in whole organism soft tissue. Regarding carboxylesterase activity, although all tissues hydrolyzed the four substrates assayed, substrate preferences varied among tissues. In particular, digestive glands showed higher carboxylesterase activity than the other tissues (299%, 359% and 137% of whole organism soft tissue activity) when measured with 1-NA, 2-NA and p-NPA as ...