Pesticides compromise health: a comparison between lizards collected within and outside an agricultural area.

Reptiles are the least studied vertebrates regarding the impact of pesticides on their health, despite being good models for ecotoxicological studies given their abundance and easy handling. Salvator merianae is widely distributed in South America and often found in agricultural cultivation areas. Here, we compared the morphological, biochemical, and physiological parameters of S. merianae from an exposed area (EA) to pesticides and a reference area (RA) or control. These parameters were measured in plasma (albumin, alanine transaminase, alkaline phosphatase, gamma-glutamyl transpeptidase, glucose, total proteins, uric acid, triglycerides, VLDL, and corticosterone) and in erythrocytes (TBARS, glutathione S-transferase, superoxide dismutase, and catalase activity). Blood samples were collected from 28 lizards (EA: three juveniles, three adult females, and three adult males; RA: nine juveniles, four females, and five males) in southern Brazil during the reproductive period. We observed a decrease in body mass, the ratio between body mass and total length and snout-vent length in juvenile lizards collected at EA. The levels of TBARS, glutathione S-transferase, triglycerides, VLDL, and uric acid were altered for juveniles in EA. When comparing the two areas, females differed in superoxide dismutase activity and total proteins, while males differed in superoxide dismutase, catalase, and glutathione S-transferase activity. This set of results shows that S. merianae, especially juveniles, suffers a negative impact when inserted in an agricultural area. The analyzed biomarkers proved suitable for monitoring these lizards and the quality of this environment.

Ecophysiological responses of Liolaemus arambarensis juveniles to experimental temperature variations.

Climate change increasingly influences the loss of biodiversity, especially in ectothermic organisms, which depend on environmental temperatures to obtain heat and regulate their life cycle. Studies that aim to understand the impact of temperature variation are important to better understand the possible impacts generated on the homeostasis of ectothermic organisms. Our objective was to characterize the responses of juvenile Liolaemus arambarensis lizards to abrupt changes in temperature, quantifying markers of body condition, intermediary and hormonal metabolism and oxidative balance. We collected 45 juvenile individuals of L. arambarensis (winter: 20 and summer: 25) in Barra do Ribeiro, Brazil. We transported the animals to the laboratory, where they were acclimatized for five days at a temperature of 20 °C, then divided and exposed to temperatures of 10 °C, 20 °C, 30 °C and 40 °C for 24 h. After exposure, the animals were euthanized and the brain, caudal muscle, thigh, and liver tissues were extracted for quantification of biomarkers of metabolism (glycogen and total proteins) and oxidative balance (acetylcholinesterase, superoxide dismutase, catalase, glutathione-S-transferase and lipoperoxidation) and plasma for corticosterone quantification. The results show that L. arambarensis is susceptible to sudden temperature variations, where higher temperatures caused greater activity of antioxidant enzymes, increased lipoperoxidation and higher plasma levels of corticosterone in animals eliminated in winter. The present study demonstrated that abrupt changes in temperature could significantly modify the homeostatic mechanisms of animals, which could lead to oxidative stress and a potential trade-off between survival and growth/reproduction. In this context, the organism mobilizes energy resources for survival, with possible damage to growth and reproduction. Demonstrate that a change in temperature can be a potential factor in extinction for a species given the profile of global climate change.

Impacts of isolated or mixed Roundup® Original DI and Boral® 500 SC herbicides on the survival and metamorphosis of Melanophryniscus admirabilis tadpoles.

The bufonid species Melanophryniscus admirabilis is restricted to a single location in the southern Atlantic Forest, Brazil. Although the site of occurrence of M. admirabilis is covered with native forest and it is not directly exposed to pesticides application, the area is surrounded by agricultural activity. Our objectives were to evaluate possible alterations in morphological parameters (body mass, snout-vent length, and body index), metamorphosis (time to reach Gosner stages 42, 46 and to complete metamorphosis), and survival of M. admirabilis exposed to isolated Roundup® Original DI (R1: 234 and R2: 2340 µg.L-1 of glyphosate) and Boral® 500 SC, (B1: 130 and B2: 980 µg.L-1 of sulfentrazone) or mixed (R1+B1, R2+B1, R1+B2, R2+B2). Spawns of M. admirabilis were collected in natural lakes in the municipality of Arvorezinha and taken to laboratory cultivation. After the tadpoles acquired free swimming, the animals were acclimated for five days and fed ad libitum. The aquariums were contaminated with herbicides on the sixth day of cultivation, and the animals stayed in these aquariums for four days. Afterwards, the tadpoles were transferred to aquariums with clean water and monitored until metamorphosis (Gosner stage 46), when they were weighed, measured (snout-cloacal length) and cryoeuthanized. We observed no alterations in morphological parameters; however, survival was reduced in exposed groups (mortality index: 71 % in R2 and 29-64 % in mixed groups), suggesting energy allocation for metamorphosis at the expense of survival. Boral did not alter metamorphosis time. Roundup isolated and mixed with Boral altered the timing of Gosner stages 42 and 46 and reduced metamorphosis time, suggesting endocrine disruption. Thus, monitoring the presence and limiting the use of these pesticides in the area where M. admirabilis occurs can be crucial for conservation strategies.

Impact of 2,4-D and glyphosate-based herbicides on morphofunctional and biochemical markers in Scinax squalirostris tadpoles (Anura, Hylidae).

Understanding the effects of pesticides on non-target organisms is essential to assess the impact of these xenobiotics on the environment, allowing for a more informative and safer usage. The present study sought to evaluate the response of Scinax squalirostris tadpoles when exposed to different concentrations of two herbicides, DEZ® (i.e., dichlorophenoxyacetic acid or 2,4-D) and Roundup® Original (i.e., glyphosate). We collected 140 tadpoles between Gosner's 25 and 34 stages in a preservation area of the South American jelly palm Butia odorata. The animals were separated into eight groups and maintained in aquariums: acclimatization control (17 days), exposure control (24 days), and six exposure groups (7 days), including three concentration groups of each pesticide (4 µg/L, 15 µg/L, and 30 µg/L 2,4-D acid equivalent; 65 µg/L, 250 µg/L, and 500 µg/L glyphosate acid equivalent). Markers of body condition (length, body mass, K and Kn index) and oxidative balance (superoxide dismutase, catalase, glutathione S-transferase, TBARS, and carbonyl proteins) were analyzed. After 24 days (17 days of acclimation plus 7 days of exposure), tadpoles exposed to 15 µg/L of 2,4-D and 65 µg/L of glyphosate grew at higher than expected concentrations. They also had less lipoperoxidation than control tadpoles and higher superoxide dismutase, catalase, and glutathione S-transferase activity, specifically at the highest herbicide concentrations (2,4-D: 30 µg/L; glyphosate: 500 µg/L of glyphosate). Only the highest concentration of 2,4-D determined an increase in the levels of carbonyl proteins, indicating oxidative damage induced. DEZ® required more antioxidant defenses and induced a concentration-dependent answer of carbonylated proteins, suggesting oxidative stress and more toxic potential. These results may help government agencies make more conscious decisions regarding the usage of these chemicals and consider a balance between the conservation of amphibian species and agribusiness economic sustenance.

Impact of commercial formulations of herbicides alone and in mixtures on the antioxidant system and body condition parameters in tadpoles of Rhinella icterica (Spix 1824).

Pesticide usage has increased over the last decades, leading to concerns regarding its effects on non-target organisms, especially amphibians. Tadpoles of Rhinella icterica were collected in a pesticide-free place, acclimated in the laboratory (21 days) and exposed (7 days) to three herbicides (20 µg/L atrazine (A); 250 µg/L glyphosate (G); 20 µg/L quinclorac (Q)) and their mixtures. Only 2% mortality was observed over the 28 days of the study. Despite this, significant variations were observed for markers of oxidative balance and body condition when comparing all experimental groups. K and Kn factor showed the lowest values in the group A+G+Q, as well as the activity levels of GST and SOD. In contrast to this, the CAT activity was higher in the same group (A+G+Q). The mixture of the three herbicides proved to be more harmful, which points to the need for more restrictive laws for the use of mixed herbicides.

Development stage-dependent oxidative stress responses to the exposure to roundup original© in a neotropical annual killifish.

Herbicides are the most commonly applied pesticides in Brazil, specifically those based on glyphosate, and are used for different crops, near the habitats of annual killifish. Annual killifish presents a short life cycle with generally restricted geographic distribution. In this context, we evaluated the effect of the Roundup Original© (65, 130 and 260 µg. L-1 of glyphosate) herbicide on different development stages (adult-young and senile) of the annual killifish (Cynopoecilus sp.). We quantified the oxidative balance markers (superoxide dismutase, catalase, glutathione S-transferase, lipid peroxidation levels, and total proteins). We observed that the senile individuals presented 2-fold higher lipid peroxidation levels associated with the maintenance of superoxide dismutase and catalase activity levels even after exposure to the herbicide. However, senile subjects were negatively impacted by the exposure to formulations containing glyphosate, and this was related to a loss of glutathione S-transferase activity. Our research demonstrated that the established physiological markers and this species look promising for toxicology studies.

Biochemical and body condition markers in Rhinella icterica tadpoles exposed to atrazine, glyphosate, and quinclorac based herbicides in ecologically relevant concentrations.

Amphibians have suffered population decline due to several factors, including exposure to pesticides. In the south of Brazil, rice cultivations use herbicides based on atrazine, glyphosate and quinclorac as the commercial formulations Primoleo®, Roundup® and Facet®, respectively. Rhinella icterica was chosen to evaluate oxidative balance markers and body condition after exposure to three concentrations of herbicides (10, 20 and 40 µg/L of atrazine and quinclorac; 100, 250 and 500 µg/L of glyphosate). These xenobiotics, regardless of the concentrations used, accelerated the development process of animals and seemed to act as modulators of development. We observed no significant variations for any of the oxidative balance markers studied (superoxide dismutase, catalase, TBARS and carbonylated proteins); however, we cannot rule out that other antioxidant system components prevent oxidative stress. In general, atrazine and glyphosate accelerated the development of tadpoles, and quinclorac retards this process, which could impact the survival of these animals.

Biomarkers of oxidative stress in the post-embryonic characterization of the neotropical annual killifish.

Annual killifish are among the most remarkable extremophile species with the shortest vertebrate life span. Few studies have reported on the oxidative balance throughout their life cycle and its association to the natural aging process of these neotropical animals in a natural environment. We standardized and analyzed physiological markers related to the redox balance of the annual killifish (Cynopoecilus fulgens) throughout the post-embryonic life cycle (enzyme activity of Superoxide Dismutase, Catalase, Glutathione Peroxidase, and Glutathione S-transferase, as well as the determination of the levels of Lipoperoxidation, Carbonylated Proteins, and Total Proteins). We tested the influence of environmental variables on these biomarkers. Individuals were collected, including juveniles, adults, and seniles, in three sampling units around the Parque Nacional da Lagoa do Peixe, located in the Coastal Plain of Rio Grande do Sul. We observed that males and females used different physiological strategies of their redox balance during their life cycle, and their oxidative balance was influenced by their reproductive period and environmental variables (water temperature, abundance of predators, abundance of another sympatric annual killifish species, and abundance of C. fulgens). The population of each temporary pond presented different physiological responses to the adaptation of their life cycle, and there was an influence of environmental component as a modulator of this cycle. Our study offers reference values that will be useful for comparison in future research with short-lived organisms.

Melanophryniscus admirabilis tadpoles' responses to sulfentrazone and glyphosate-based herbicides: an approach on metabolism and antioxidant defenses.

Melanophryniscus admirabilis is a frog endemic to the southern Atlantic Forest (Brazil), with restricted distribution and considered as critically endangered. The aim of this study was to evaluate possible alterations in biomarkers of metabolism (glycogen, proteins, and uric acid) and oxidative balance (superoxide dismutase, catalase, glutathione S-transferase, and lipoperoxidation) of tadpoles of Melanophryniscus admirabilis exposed to commercial herbicide formulations containing sulfentrazone (Boral® 500 SC: 130 and 980 µg a.i./L) and glyphosate (Roundup® Original: 234 and 2340 µg a.i./L). Mortality was not observed in any of the groups studied. Our results show that a 96-h exposure to the herbicides decreased glycogen levels, indicating increased energy demand for xenobiotic metabolism. Protein levels increased in the Boral group but decreased in the higher concentration of Roundup, and uric acid levels did not change significantly between the experimental groups. Lipoperoxidation decreased in the Boral group and in the higher concentration of Roundup. Decreased levels of superoxide dismutase in both treatments and of catalase in the lowest concentration of the herbicides were observed. Glutathione S-transferase activity increased in the Roundup group; this enzyme seems to be crucial in the metabolization of the herbicides and in the survival of the tadpoles. Our results suggest that M. admirabilis has a high antioxidant capacity, which guaranteed the survival of tadpoles. Nevertheless, exposure to pesticides could impose a serious risk to this species, especially considering its restricted distribution, habitat specificity, and high physiological demand to metabolize xenobiotics.

Assessing the influence of biotic, abiotic, and social factors on the physiological stress of a large Neotropical primate in Atlantic forest fragments.

Wildlife physiological responses to environmental and human-related stressors provide useful clues on animal welfare. Non-invasive biomarkers, such as fecal glucocorticoid metabolites (fGCM), allow researchers to assess whether variations in habitat quality, behavior, and climate influence the animals' physiological stress. We examined the role of fragment size, ambient temperature, ripe fruit availability and consumption, percentage of records moving, sex, female reproductive state, and group composition as predictors of the level of fGCM in adult brown howler monkeys (Alouatta guariba clamitans) inhabiting three small (<10 ha) and three large (>90 ha) Atlantic Forest fragments in southern Brazil. We collected bimonthly behavioral data and fecal samples from adult individuals over three years, and used a multimodel inference framework to identify the main predictors of fGCM. We found that the mean (±SD) fGCM in the study groups ranged from 57 ±â€¯49 ng/g to 93 ±â€¯58 ng/g, which were within the known range for howler monkeys. We found 10 best models including five of the 17 tested variables. Sex and reproductive state were the only variables included in all these models. We found that fGCM was higher in nursing females (mean ±â€¯SD = 104 ±â€¯73 ng/g) than in non-nursing females (64 ±â€¯55 ng/g) and males (53 ±â€¯40 ng/g, P < 0.05) and that it decreased with increasing ripe fruit consumption and minimum temperature. However, fragment size did not predict fGCM concentration (groups in small fragments = 71 ±â€¯58 ng/g vs. groups in large fragments = 63 ±â€¯54 ng/g, P > 0.05). We conclude that factors related to the energetic balance of individuals play major roles in modulating the physiological stress of brown howler monkeys. Future studies should investigate the consequences of higher levels of stress hormones on howler monkey health and demography.

Extracts of the unripe fruit of Ilex paraguariensis as a potential chemical control against the golden apple snail Pomacea canaliculata (Gastropoda, Ampullariidae).

Plant extracts can provide a viable alternative to controlling many crop pests. This study sought to assess the efficacy of vegetable extracts of the unripe fruits of Ilex paraguariensis (yerba maté) for chemical control of the channeled apple snail (Pomacea canaliculata) and of non-target species as the South American catfish (Rhamdia quelen) under laboratory conditions. In P. canaliculata, the LC50 of the decoction extract was 31.39 mg.L-1 and the LT50 was over 26 h. The LC50 of the butanol extract was 24.75 mg.L-1 and the LT50 was in the range of 28 to 32 h. In juvenile R. quelen, the LC50 of the decoction was 17.98 mg.L-1 and the LT50 was in the range of 10-12 h. These extracts are particularly attractive considering the source of compounds and their effectiveness as molluscicides.

Changes in intermediate metabolism and oxidative balance parameters in sexually matured three-barbeled catfishes exposed to herbicides from rice crops (Roundup®, Primoleo® and Facet®).

This study analyzed the effect of different concentrations of herbicides (Facet®, Primoleo®, and Roundup®) on metabolism and oxidative balance (superoxide dismutase and catalase activity, lipid peroxidation) in the gills, liver, kidneys, and tail muscle of adult catfish. All herbicides caused protein depletion in gills, increased glycogen and triacylglycerol consumption in the liver, and changes in muscle glycogen. Roundup® and Primoleo® stimulated lipid deposition in the liver, while Roundup® and Facet® stimulated lipid consumption in gills. In kidneys, protein content increased after Roundup® and Primoleo® exposure, glycogen increased after Facet®, and lipids increased after Roundup®. Primoleo® had the strongest effect on muscle, with changes in all metabolites. Regarding oxidative stress, the liver and kidneys were the organs most affected by exposure to herbicides, and catalase was the main enzyme involved in the detoxification of these herbicides. A hierarchy of toxicity was established for the tested chemicals: Facet® > Primoleo® > Roundup®.

Metabolic parameters and oxidative balance in juvenile Rhamdia quelen exposed to rice paddy herbicides: Roundup®, Primoleo®, and Facet®.

The present study sought to assess the response of Rhamdia quelen juveniles (6-8 cm total body length) to exposure to different concentrations of three herbicides: Roundup® Original (18, 36, 72, and 144 µg/L), Primoleo® (2.5, 5, 10, and 15 µg/L), and Facet® (1.75, 3.5, 7, and 14 µg/L). Total protein (TP), glycogen (GG), total lipids (TL), triacylglycerols (TAG), lipid peroxidation (TBARS), and activity of the antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) in gills, liver, kidneys, and muscle were measured by spectrophotometry. Roundup® (glyphosate) reduced the TP, GG, and TL in gills and TL in liver and kidney and increased TP in liver and increased GG in muscle. In contrast to Primoleo® (atrazine), all tissues stored TAG and consumed LT, besides the gills also reduced PT. There was still an increase in GG in the kidneys and muscle. Facet® (quinclorac) induced changes mainly in the liver (increased TP, TL, and TAG content) and muscle (increased GG, TL, and TAG depletion). Gill tissue exhibited TP depletion alone, and kidney tissue metabolism was unchanged. This fish species appears capable of modulating its enzymes to the point where it sustains no oxidative damage as a result of exposure to the herbicides glyphosate (possibly due to increased CAT activity), atrazine (despite no changes in SOD or CAT activity), and quinclorac (with increased lipid peroxidation, particularly in gill, kidney, and muscle tissue, despite elevated SOD activity). Although it is not considered a target species, R. quelen suffers harmful effects from interaction with these herbicides.

Oxidative Status Profile in Different Tissues of Parastacus brasiliensis promatensis (Crustacea, Decapoda, Parastacidae) over a Seasonal Cycle.

The objective of this study was to assess annual redox balance by quantifying activity of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and glutathione S-transferase (GST), as well as measuring lipid peroxidation levels by determination of thiobarbituric acid-reactive substances, in different tissues of male and female crayfish collected from an area little affected by anthropogenic impacts. A total of 37 male and 32 female of Parastacus brasiliensis promatensis were collected over an annual cycle, and gill, muscle, hepatopancreas, and gonad samples were harvested and subjected to the aforementioned analyses via spectrophotometry. Comparison of the annual oxidative status response profile in gill and in hepatopancreas between males and females revealed differences only in SOD activity. In abdominal muscle, this comparison revealed a distinct profile of SOD and GST activity, as well as of lipid peroxidation. SOD activity in gonads of females increased in the summer when compared to autumn; conversely, CAT and GST levels did not differ over the year. During reproduction, a possible increase of the energy requirements led to an increase in lipid peroxidation in all tested tissues, in males and females alike. It was least evident in female gonad tissue, which suggests this tissue type is relatively protected; within this context, one may establish a tissue-specific grading of Lipid Peroxidation intensity in females of the species during the spring: gonads < muscle < gills < hepatopancreas. Our results show that the responses of the defenses analyzed antioxidants, as well as lipid peroxidation levels, were sex and tissue dependent and a clear pattern of seasonal variation.

Seasonal variability of metabolic markers and oxidative balance in freshwater amphipod Hyalella kaingang (Crustacea, Amphipoda).

Amphipods are widely used as bioindicator organisms, in view of their ease of collection and cultivation, sexual dimorphism and abundance, in aquatic environments. In the present study male (n=30) and female (n=30) amphipod Hyalella kaingang were collected during the middle of each season from a nature preserve (Research Center PRÓ-MATA) in São Francisco de Paula, Southern Brazil. Proteins, glycogen, lipids, triglycerides, glycerol, and lipid peroxidation (superoxide dismutase, catalase, and glutathione S-transferase activity) were measured. The results obtained for the markers of energy metabolism, antioxidant enzymes, and lipid peroxidation revealed a clear seasonal variation. The patterns of proteins, glycerol, and glutathione S-transferase activity did not differ between sexes; conversely, differential responses in males and females over the year were observed for all other parameters (glycogen, lipids, triglycerides, lipid peroxidation, and superoxide dismutase and catalase activity). These responses appear to be strongly influenced by a prolonged reproductive period (autumn through spring, peaking in autumn); by the degree of exploratory activity, particularly in the summer and autumn; and by abiotic factors, such as temperature and photoperiod. The responses observed in the summer and autumn (decrease in levels of proteins, glycogen and fats, and increase in lipid peroxidation levels and glutathione S-transferase activity), suggest that this season represents a critical time point for these animals. The parameters studied herein may be used as biomarkers to assess the environmental conditions in the aquatic habitat.

Effect of atrazine, glyphosate and quinclorac on biochemical parameters, lipid peroxidation and survival in bullfrog tadpoles (Lithobates catesbeianus).

Increased use of pesticides worldwide has led to damage not only to natural ecosystems but also to nontarget species. This study assessed the effects of different concentrations of the herbicides atrazine, glyphosate, and quinclorac on biochemical parameters, lipid peroxidation, and survival in tadpoles of Lithobates catesbeianus (bullfrog). Two hundred eighty-eight tadpoles were acquired from a frog farm in the south of Brazil. All animals were kept in aquariums under controlled laboratory conditions for 7 days and exposed to commercial formulations of atrazine (5, 10, and 20 µg/L), glyphosate (36, 72, and 144 µg/L), and quinclorac (0.05, 0.10, and 0.20 µg/L) for 7 days thereafter. The concentrations used in this study are similar to the levels of these herbicides found in natural water bodies. After exposure, gill, liver, and muscle samples were removed from each animal for quantitation of glycogen, total lipids, triglycerides, cholesterol, total proteins, and lipid peroxidation. Atrazine, glyphosate, and quinclorac exposure induced a significant decrease in levels of glycogen and total lipids in gill, liver, and muscle. Triglycerides levels in the gill increased after exposure to glyphosate, and decreased after exposure to atrazine and quinclorac; their levels in liver and muscle decreased on exposure to all herbicides. Cholesterol and total protein levels decreased in liver and muscle for all three herbicides. All tissues exhibited increased lipid peroxidation after exposure to all herbicides. In conclusion, exposure to the herbicides tested in this study induced significant changes in biochemical parameters and increased lipid peroxidation levels in tadpoles of L. catesbeianus.

Metabolic responses in two species of crayfish (Parastacus defossus and Parastacus brasiliensis) to post-hypoxia recovery.

The period of post-hypoxia recovery is essential for the rapid replenishment of energy reserves and for the removal of metabolic end products formed during hypoxia. Periods of post-hypoxia recovery were analyzed in two crayfish species, where Parastacus defossus is a fossorial species, and Parastacus brasiliensis lives in lotic environments with higher oxygen levels. After 4 h of hypoxia (2 mg O(2)/L), groups of animals were placed in tanks with oxygenated water and were then removed at intervals of 1, 3, 6, and 9 h. Hemolymph and tissues (hepatopancreas, muscle, and anterior and posterior gills) were extracted for the determination of glucose, lactate, free glucose, glycogen, total proteins, total lipids, arginine phosphate, and arginine. As expected, lactate levels were restored more rapidly in P. defossus than in P. brasiliensis. P. defossus restored its glycogen reserves of the hepatopancreas and muscle tissue. Free glucose was quickly restored in all tissues of both species. In relation to arginine phosphate reserves, P. defossus showed a greater ability to restore this metabolite in the hepatopancreas. Both species recovered their arginine phosphate reserves, but they also used this metabolite in longer periods of recovery. Mainly in P. brasiliensis the reserves of total lipids seem to be an important source of energy during the recovery period. The animals developed various metabolic strategies to post-hypoxia recovery, mainly P. defossus which restored its reserves more completely and more rapidly than did P. brasiliensis.

Detection of anti-oxidant enzymatic activities and purification of glutathione transferases from Angiostrongylus cantonensis.

There are several anti-oxidant enzyme families that play pivotal roles in facilitating the survival of parasites. Glutathione transferases (GSTs) are members of the anti-oxidant family that can detoxify a broad range of exogenous or endogenous compounds including reactive oxidative species. GSTs have been studied as vaccine candidates, immunodiagnostic markers and as treatment targets. Helminths of the genus Angiostrongylus live inside arteries of vertebrates and two main species are associated with accidental human infections: Angiostrongylus costaricensis adult worms live inside the mesenteric arteries and larvae of Angiostrongylus cantonensis become trapped in the central nervous system vasculature. Since the interactions between angiostrongylid nematodes and their vertebrate hosts are poorly understood, this study characterized the anti-oxidant enzymatic activities of A. cantonensis from female worms by collecting excreted and secreted (ES) and total extract (TE) molecules. Catalase (CAT) and superoxide dismutase (SOD) activities were found both in the ES and TE while glutathione peroxidase (GPX) and GST were found only in the TE. GSTs were purified by glutathione agarose affinity column (AcGST) and the pool of eluted GSTs was analyzed by mass spectrometry (LC-MS/MS) and de novo sequencing (Masslynx software). Sequences from two peptides (AcGSTpep1 and AcGSTpep2) present high identity to the N-terminal and C-terminal from sigma class GSTs of nematodes. It is known that these GST enzymes are associated with host immune regulation. Furthermore, understanding the role of parasite-derived anti-oxidant molecules is important in understanding host-parasite interactions.

Effect of Roundup® (glyphosate formulation) in the energy metabolism and reproductive traits of Hyalella castroi (Crustacea, Amphipoda, Dogielinotidae).

Roundup(®) (glyphosate formulation) is a nonselective and posts emergent herbicide used for controlling aquatic weeds and different concentrations are used in cultures around the world. The objective of this investigation was to examine the effects of Roundup(®) (glyphosate formulation) on the biochemical composition, levels of lipoperoxidation, Na(+)/K(+)ATPase activity and reproductive traits in the Hyalella castroi. Amphipods were collected in summer 2009, in the southern Brazilian highlands. In the laboratory, the animals were kept in aquariums under controlled conditions for 7 days, and after this period they were exposed to 0.36, 0.52, 1.08 and 2.16 mg/l of glyphosate for 7 days. After the period of exposure, the animals were immediately frozen for determination of glycogen, proteins, lipids, triglycerides, cholesterol, levels of lipoperoxidation, and Na(+)/K(+)ATPase activity. During each day of the cultivation reproductive traits (number of reproductive pairs, ovigerous females and eggs in the marsupium) were observed. All concentrations of Roundup(®) induced significant decreases in all biochemical parameters and Na(+)/K(+)ATPase activity, and significant increase in lipoperoxidation levels. Showing this form a potentially toxic effect at very low concentrations, this pattern of results can lead to significant changes in trophic structure of limnic environments because these amphipods are important links in food chain in these habitats.

Metabolic responses of Parastacus defossus and Parastacus brasiliensis (Crustacea, Decapoda, Parastacidae) to hypoxia.

The metabolic responses of two crayfish species living in different habitats, Parastacusdefossus and Parastacus brasiliensis, were analyzed after different periods of hypoxia (2.0mg O(2)/L of oxygen). In the laboratory, groups of animals were subjected to hypoxia for 1, 2, 4, and 8h. The hemolymph, hepatopancreas, muscle, and anterior and posterior gills were removed for determination of glucose, free glucose, glycogen, lactate, total proteins, total lipids, total cholesterol, arginine, and arginine phosphate. In both species, glucose and lactate increased significantly after 4h of hypoxia, but decreased after 8h (p>0.05) from the beginning of the experiment. Reductions of glycogen, lipids, and cholesterol were recorded in hepatopancreas and muscle tissue, especially of P. defossus, after 4h of hypoxia. Free glucose levels decreased in all tissues of P. brasiliensis, mainly in the hepatopancreas and muscle (p<0.05), while P. defossus showed smaller reductions of these reserves. All reserves in the anterior and posterior gills, with exception of the glycogen reserves, behaved similarly in both species. Both crayfishes stored and used arginine phosphate, mainly P. defossus, which also showed higher concentrations of all metabolites than did P. brasiliensis. Both species showed metabolic adaptations to hypoxia, but, as expected, P. defossus appeared to be better adapted.