Anacardium microcarpum extract and fractions protect against paraquat-induced toxicity in Drosophila melanogaster

Anacardium microcarpum Ducke (Anacardiaceae) is a native species of Brazil used in folk medicine for the treatment of several illnesses although its antioxidant activity has been reported in vitro, there is no evidence of this effect in an in vivo model. Here, we investigated the potential protective effect of hydroalcoholic extract (AMHE), methanol (AMMF) and acetate (AMAF) fraction of A. microcarpum against paraquat toxicity on survivorship, locomotor performance, antioxidant enzymes activity and reactive species using Drosophila melanogaster. Flies were exposed to the extract or fractions (1 and 10 mg/ml) in the presence or absence of paraquat (5 mM) in sucrose solution for 72 h. In addition, total phenolic content of extract and fractions was evaluated as well as ABTS radical scavenging capacity. Our results demonstrated that AMAF presented higher content of phenols and ABTS chelating potential. Treatment of flies with the extract or fractions did not alter the survivorship, locomotor ability, and acetylcholinesterase (AchE) activity per se. Paraquat caused 85 % mortality of flies and 30 % increase in reactive species generation, which were significantly attenuated by AMHE and AMMF. AAMF increased catalase activity (from 66.77 ± 6.64 to 223.94 ± 25.92 mU/mg of protein), while AMAF increased GST activity (from 477.76 ± 92 to 770.19 ± 147.92 mU/mg of protein) and catalase activity (from 66.77 ± 6.64 to 220.54 ± 26.63 mU/mg of protein). AMHE and AMMF were more effective in protecting against paraquat toxicity. Taken together, the data indicate the potential of this plant in acting as a protective and antioxidant agent in vivo

Phytochemical Constituents and Toxicity of Duguetia furfuracea

Duguetia furfuracea is frequently used as a medicinal plant in Brazil. However, studies have evidenced its cytotoxic, bactericide, and antitumor activities. In the present study we aimed to evaluate the potential toxicity of hydroalcoholic leaves extracts of D. furfuracea (HEDF) in a Drosophila melanogaster model. Toxicity was assessed as changes in locomotor performance, mitochondrial activity, oxidative stress, MAPKs phosphorylation, and apoptosis induction after exposure to HEDF concentrations (1–50 mg/mL) for 7 days. The phytoconstituents of the plant were screened for the presence of alkaloids, tannins, xanthones, chalcones, flavonoids, aurones, and phenolic acids. Exposure of adult flies to HEDF caused mitochondrial dysfunction, overproduction of ROS, and alterations in the activity of detoxifying enzymes GST, SOD and CAT. Induction of ERK phosphorylation and PARP cleavage was also observed, indicating occurrence of HEDF-induced cell stress and apoptotic cell death. In parallel, alterations in cholinesterase activity and impairments in negative geotaxis behavior were observed. Our study draws attention to the indiscriminate use of this plant by population and suggests oxidative stress as a major mechanism underlying its toxicity

Anacardium microcarpum Promotes Neuroprotection Dependently of AKT and ERK Phosphorylation but Does Not Prevent Mitochondrial Damage by 6-OHDA

Parkinson’s disease is a degenerative and progressive illness characterized by the degeneration of dopaminergic neurons. 6-hydroxydopamine (6-OHDA) is a widespread model for induction of molecular and behavioral alterations similar to Parkinson and has contributed for testing of compounds with neuroprotective potential. The Brazilian plant Anacardium microcarpum is used in folk medicine for treatment of several illnesses; however, the knowledge about toxicology and biological effects for this plant is very rare. The neuroprotective effect from hydroalcoholic extract and methanolic and acetate fraction of A. microcarpum on 6-OHDA-induced damage on chicken brain slices was investigated in this study. 6-OHDA decreased cellular viability measured by MTT reduction assay, induced lipid peroxidation by HPLC, stimulated Glutathione-S-Transferase and Thioredoxin Reductase activity, and decreased Glutathione Peroxidase activity and the total content of thiols containing compounds. The methanolic fraction of A. microcarpum presented the better neuroprotective effects in 6-OHDA-induced damage in relation with hydroalcoholic and acetate fraction. The presence of AKT and ERK1/2 pharmacological inhibitors blocked the protective effect of methanolic fraction suggesting the involvement of survival pathways in the neuroprotection by the plant. The plant did not prevent 6-OHDA autoxidation or 6-OHDA-induced mitochondrial dysfunction. Thus, the neuroprotective effect of the methanolic fraction of A. microcarpum appears to be attributed in part to chelating properties of extract toward reactive species and is dependent on ERK1/2 and AKT phosphorylation. This study contributes to the understanding of biochemical mechanisms implied in neuroprotective effects of the vegetal species A. microcarpum

Croton campestris A. St.-Hill Methanolic Fraction in a Chlorpyrifos-Induced Toxicity Model in Drosophila melanogaster: Protective Role of Gallic Acid

Croton campestris A. St-Hill popularly known as “velame do campo” is a native species of the savannah from northeastern Brazil, being used in folk medicine due to its beneficial effects in the treatment of many diseases, inflammation, detoxification, gastritis, and syphilis; however, its potential use as an antidote against organophosphorus compound poisoning has not yet been shown. Here, the protective effect of the methanolic fraction of C. campestris A. St.-Hill (MFCC) in Drosophila melanogaster exposed to chlorpyrifos (CP) was investigated. Flies were exposed to CP and MFCC during 48 h through the diet. Following the treatments, parameters such as mortality, locomotor behavior, and oxidative stress markers were evaluated. Exposure of flies to CP induced significant impairments in survival and locomotor performance. In parallel, increased reactive oxygen species and lipoperoxidation occurred. In addition, the activity of acetylcholinesterase was inhibited by CP, and superoxide dismutase and glutathione S-transferase activity was induced. Treatment with MFCC resulted in a blockage of all CP-induced effects, with the exception of glutathione S-transferase. Among the major compounds found in MFCC, only gallic acid (GA) showed a protective role against CP while quercetin and caffeic acid alone were ineffective. When in combination, these compounds avoided the toxicity of CP at the same level as GA. As far as we know, this is the first study reporting the protective effect of MFCC against organophosphate toxicity in vivo and highlights the biotechnological potential of this fraction attributing a major role in mediating the observed effects to GA. Therefore, MFCC may be considered a promising source for the development of new therapeutic agents for the treatment of organophosphate intoxications