Enzymatic responses in the head and midgut of Africanized Apis mellifera contaminated with a sublethal concentration of thiamethoxam

Author(s)

Decio, Pamela ^[1] ; Miotelo, Lucas ^[1] ; Pereira, Franco Dani Campos ^{[1, 2]} ; Roat, Thaisa Cristina ^[1] ; Marin-Morales, Maria Aparecida ^[1] ; Malaspina, Osmar ^[1]

Affiliation

^[1] Sao Paulo State Univ Unesp, Inst Biosci, Ave 24A, 1515, BR-13506900 Rio Claro, SP - Brazil

^[2] NUPEFEN Nucleo Pesquisas Educ Fis Estet & Nutr, Claretiano Univ Ctr, Ave Santo Antonio Maria Claret, BR-13503257 Rio Claro, SP - Brazil

• Document type: Journal article
• Source: ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY; v. 223, OCT 15 2021.
• Web of Science Citations: 0

Abstract

The increasing use of insecticides, promoted by the intensification of agriculture, has raised concerns about their influence on the decline of bee colonies, which play a fundamental role in pollination. Thus, it is fundamental to elucidate the effects of insecticides on bees. This study investigated the damage caused by a sublethal concentration of thiamethoxam - TMX (0.0227 ng/mu L of feed) in the head and midgut of Africanized Apis mellifera, by analyzing the enzymatic biomarkers, oxidative stress, and occurrence of lipid peroxidation. The data showed that the insecticide increased acetylcholinesterase activity (AChE) and glutathione-S-transferase (GST), whereas carboxylesterase (CaE3) activity decreased in the heads. Our results indicate that the antioxidant enzymes were less active in the head because only glutathione peroxidase (GPX) showed alterations. In the midgut, there were no alkaline phosphatase (ALP) or superoxide dismutase (SOD) responses and a decrease in the activity of CaE was observed. Otherwise, there was an increase in GPX, and the TBARS (thiobarbituric acid reactive substances) assay also showed differences in the midgut. The TBARS (thiobarbituric acid reactive substances) assay also showed differences in the midgut. The results showed enzymes such as CaE3, GST, AChE, ALP, SOD, and GPX, as well as the TBARS assay, are useful biomarkers on bees. They may be used in combination as a promising tool for characterizing bee exposure to insecticides. (AU)

• FAPESP's process: 14/23197-7 - Cellular stress and activity of biomarkers enzymes in Africanized honeybees Apis mellifera Lineu, 1758 (Hymenoptera, Apidae) exposed to thiamethoxam
• Grantee: Pâmela Decio Horst
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 17/21097-3 - Bee-agriculture interactions: perspectives to sustainable use
• Grantee: Osmar Malaspina
• Support Opportunities: BIOTA-FAPESP Program - Thematic Grants
• FAPESP's process: 12/13370-8 - How is the reaction of the Apis mellifera brain to a sublethal dose of thiamethoxam?
• Grantee: Thaisa Cristina Roat
• Support Opportunities: Research Grants - Young Investigators Grants