Glyphosate-based herbicide exposure causes antioxidant defence responses in the fruit fly Drosophila melanogaster.

Glyphosate is a non-selective and post-emergent herbicide that affects plant growth. Animal exposure to this herbicide can lead to adverse effects, such as endocrine disruption, oxidative stress and behavioural disorders. Drosophilids have been utilized previously as an effective tool in toxicological tests. In the present study, the effects of a glyphosate-based herbicide (Roundup [Original]) were investigated regarding oxidative stress, the antioxidant defence system and acetylcholinesterase (AChE) activity in Drosophila melanogaster. Flies (of both genders) that were 1 to 3days old were exposed to different glyphosate concentrations (0.0g/L=control, 1.0g/L, 2.0g/L, 5.0g/L and 10.0g/L) [corrected] in the diet for 24h and 96h. After the exposure periods, reactive oxygen species (ROS) levels, antioxidant capacity against peroxyl radicals (ACAP) and lipid peroxidation (LPO) levels were quantified. In addition, the mRNA expression of antioxidant genes (i.e., keap1, sod, sod2, cat, irc, gclc, gclm, gss, trxt, trxr-1 and trxr-2) was evaluated via RT-PCR. Additionally, AChE activity was evaluated only after the 96h exposure period. The results indicated that Roundup exposure leads to a reduction in ROS levels in flies exposed for 96h. ACAP levels and gene expression of the antioxidant defence system exhibited an increase from 24h, while LPO did not show any significant alterations in both exposure periods. AChE activity was not affected following Roundup exposure. Our data suggest that Roundup exposure causes an early activation of the antioxidant defence system in D. melanogaster, and this can prevent subsequent damage caused by ROS.

de Aguiar LM ，Figueira FH ，Gottschalk MS ，da Rosa CE ... -  《COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY C-TOXICOLOGY & PHARMACOLOGY》

Embryo-larval exposure to atrazine reduces viability and alters oxidative stress parameters in Drosophila melanogaster.

Figueira FH ，Aguiar LM ，Rosa CE 《COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY C-TOXICOLOGY & PHARMACOLOGY》

Effects of the herbicide Roundup on the polychaeta Laeonereis acuta: Cholinesterases and oxidative stress.

Glyphosate based herbicides, including Roundup, are widely employed in agriculture and urban spaces. The objective of this study was to evaluate the toxicological effects of Roundup on the estuarine polychaeta Laeonereis acuta. Biomarkers of oxidative stress as well as acetylcholinesterase and propionilcholinesterase activities were analyzed. Firstly, the LC50 96h for L. acuta was established (8.19mg/L). After, the animals were exposed to two Roundup concentrations: 3.25mg/L (non-observed effect concentration - NOEC) and 5.35mg/L (LC10) for 24h and 96h. Oxygen consumption was determined and the animals were divided into three body regions (anterior, middle and posterior) for biochemical analysis. An inhibition of both cholinesterase isoforms were observed in animals exposed to both Roundup concentrations after 96h. A significant reactive oxygen species (ROS) reduction was observed in the posterior region of animals in both periods, while antioxidant capacity against peroxyl radicals (ACAP) was reduced in the posterior region of animals exposed for 24h. Considering the antioxidant defense system, both GSH levels and enzyme activities (catalase, superoxide dismutase, glutathione s-transferase, glutathione peroxidase and glutamate cysteine ligase) were not altered after exposure. Lipid peroxidation was reduced in all analyzed body regions in both Roundup concentrations after 24h. Animals exposed to the highest concentration presented a reduction in lipid peroxidation in the anterior region after 96h, while animals exposed to the lowest concentration presented a reduction in the middle region. Overall results indicate that Roundup exposure presents toxicity to L. acuta, causing a disruption in ROS and ACAP levels as well as affects the cholinergic system of this invertebrate species.

de Melo Tarouco F ，de Godoi FGA ，Velasques RR ，da Silveira Guerreiro A ，Geihs MA ，da Rosa CE ... -  《-》

Glyphosate Adversely Affects Danio rerio Males: Acetylcholinesterase Modulation and Oxidative Stress.

Lopes FM ，Caldas SS ，Primel EG ，da Rosa CE ... -  《-》

Effects of a glyphosate-based herbicide on survival and oxidative status of a non-target herbivore, the Colorado potato beetle (Leptinotarsa decemlineata).

Glyphosate is the globally most used herbicide against a wide range of weeds. Glyphosate has been considered safe to animals as it mainly targets physiological pathways in plants. However, recent toxicological studies have revealed that glyphosate can cause various toxic effects also on animals. In this study, we investigated the direct toxic effects of a glyphosate-based herbicide (GBH, Roundup® Bio) on 1) survival and 2) oxidative status of a non-target herbivore by using Colorado potato beetles (Leptinotarsa decemlineata), originating from Poland and USA, as model species. Larvae were randomly divided into three groups: 1) high concentration (100% Roundup Bio, 360 g/l), 2) low concentration (1.5% Roundup Bio) and 3) control group (water). Larvae were exposed to Roundup for different time periods: 2 h, 24 h, 48 h, 72 h and 96 h. Larval survival decreased in the group treated with high concentration of GBH compared to controls, whereas the low concentration group did not differ from the control group. GBH treatment had no association with oxidative status biomarkers (i.e. catalase, superoxide dismutase, glutathione-S-transferase, glutathione and glutathione related enzymes), but increased lipid hydroperoxide levels after 2 h exposure, suggesting increased oxidative damage soon after the exposure. Larvae of different origin also differed in their oxidative status, indicating population-dependent differences in antioxidant defence system. Environmentally relevant concentrations of GBH are not likely to affect larval survival, but high concentrations can reduce survival and increase oxidative damage of non-target herbivores. Also, populations of different origin and pesticide usage history can differ in their tolerance to GBH.

Rainio MJ ，Margus A ，Lehmann P ，Helander M ，Lindström L ... -  《COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY C-TOXICOLOGY & PHARMACOLOGY》