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Context: Parkinson’s disease (PD) is characterized by motor-symptoms attributed to profound (60 – 70%) neurodegeneration in the striatum and loss of dopamine thereof. Oxidative stress, mitochondrial dysfunction and neuroinflammation are major contributors to neurodegenerative pathogenesis of PD. Epipremnum aureum is an ornamental plant found to possess significant antioxidant and anti-inflammatory properties. Aims: To evaluate the neuroprotective potential of ethanol extract of E. aureum (EEA) leaves against rotenone-induced neurotoxicity in rats. Methods: Stereotaxic brain surgery was performed on day 1 and rotenone (ROT) was injected (300 µg/µL) in the substantia nigra pars compacta (SNpc) to induce PD in rats. EEA (125, 250 and 500 mg/kg, p.o.) was administered to ROT-treated rats for 28 consecutive days. Rearing behavior, ambulation, catalepsy and paw retraction test were performed on day 28. After behavioral tests, rats were sacrificed, whole-brain removed and TBARS, GSH and catalase activity was determined in brain homogenate. Results: ROT-treated rats showed a conspicuous increase in the catatonic score, paw retraction time and decline in the ambulatory score and rearing score that exhibited induction of PD in rats. The motor-symptoms triggered by rotenone were significantly reversed in EEA (250 and 500 mg/kg) treated animals. EEA treatment significantly attenuated the intranigral ROT induced rise in brain TBARS and a decline in GSH content and catalase activity. Conclusions: The study demonstrated that in the present model of PD, treatment with EEA mitigates the key symptoms (e.g. hypokinesia, rigidity and postural instability) through potent antioxidant activity.

Introduction: Parkinson’s disease (PD) is a neurological disorder associated with the selective loss of dopaminergic (DAergic) neurons. Clinical data suggest that oxidative stress (OS) and dysregulation of glucose (G) metabolism are early events in PD. However, no data are available to explain the molecular connection between glucose metabolism, OS, and neuronal demise in PD. Human lymphocytes share a similar dopaminergic signaling mechanism with DAergic neurons. Further, rotenone (ROT) is a mitochondrial complex I inhibitor that selectively induces apoptosis through OS in dopaminergic neurons and lymphocytes. Thus, to test the hypothesis that G metabolism and OS are linked in dopaminergic system toxicity and PD, human lymphocytes were cultured with ROT in the presence or absence of various concentrations of glucose. Objective: This study examines the response of human lymphocytes to glucose (11, 55, 166, 277, 555 mM G) in the absence or presence of ROT (250 microM). Methods: Light and fluorescence microscopy and immunocytochemistry techniques were used to evaluate morphological and biochemical changes in human lymphocytes. Results: 55 mM G was effective in suppressing ROT-induced apoptosis in lymphocytes via 5 pathways: (i) pentose phosphate pathway (PPP), (ii) glutathione (GSH) pathway, (iii) superoxide dismutase (SOD) and catalase (CAT) antioxidant systems, and (iv) Phosphoinositide 3-kinase (PI3-K) signaling. Additionally, we report for the first time that G rescued lymphocytes from ROT-induced apoptosis by (v) activating NF-kB and down-regulating p53 and caspase-3. Signaling (e.g., LY294002) and metabolic inhibitors of these pathways (e.g., dehydroepiandrosterone (DHEA), L-buthioninesulfoximine (BSO), 1,3-Bis (2-chloroethyl)-1-nitrosourea (BCNU), mercaptosuccinic acid (MS), 3-amino-1,2,4- triazole (AT), sodium diethyldithiocarbamate (DDC)) only partially reversed the protective effect of 55 mM G on lymphocytes exposed to ROT. Conclusion: These data suggest that high G simultaneously triggers cellular signaling and antioxidant systems to ensure global cell protection against stressful conditions in DAergic cells.

Studies with botanical insecticides have become more popular as an alternative to Integrated Pest Management. The purpose of this study was to evaluate the effect of leaf and fruit aqueous extracts, from the species Clibadium sylvestre, and leaves and root of Derris amazonica species at concentrations of 0, 1, 2, 4 and 8%, in the control of the aphid Myzus persicae (Hemiptera: Aphididae). Four experiments were conducted; two tests with choice preference and two tests with no choice preference, giving nine treatments and five repetitions. Phytochemical screening was carried out from the leaves and fruit of the species C. sylvestre and leaves and root of D. amazonica. Evaluations of mortality, number of nymphs, and deterrence index of the insects were conducted 24, 48 and 72 h after the application of the extracts. The aqueous extracts tested from C. sylvestre fruit concentrations had the highest mortality compared to the control; in the analysis of the number of the nymphs, the aqueous extract from fruit at 8% concentration had a higher efficiency than the other treatments. The D. amazonica leaves extract at 1% concentration showed the highest mortality and the lowest number of nymphs. The D. amazonica root extracts increased mortality at all concentrations tested, and the 8% concentration had the fewest nymphs. All treatments showed a deterrent effect. The 72 h period showed the greatest effect of the extracts, on two species of insects.Estudos com inseticidas botânicos vêm ganhando espaço como alternativa no Manejo Integrado de Pragas. Conduziu-se este trabalho com o objetivo de avaliar o efeito de extratos aquosos de folhas e frutos da espécie Clibadium sylvestre, e folhas e raízes da espécie Derris amazonica nas concentrações 0, 1, 2, 4 e 8%, no controle do pulgão Myzus persicae (Hemiptera: Aphididae). Foram conduzidos quatro ensaios, dois testes de preferência sem chance de escolha e dois testes de preferência com chance de escolha, totalizando nove tratamentos com cinco repetições. Foi realizada a triagem fitoquímica das folhas e dos frutos da espécie C. sylvestre e das folhas e das raízes de D. amazonica. As avaliações de mortalidade, número de ninfas e índice de deterrência dos insetos, foram realizadas 24, 48 e 72 horas após a aplicação dos extratos. Os extratos aquosos do fruto do C. sylvestre nas concentrações testadas apresentaram maior mortalidade frente à testemunha, na análise do número de ninfas, o extrato aquoso do fruto do C. sylvestre a 8% apresentou maior eficiência que os demais tratamentos. O extrato da folha de D. amazonica na concentração 1% apresentou maior mortalidade e menor número de ninfas que os demais tratamentos. Os extratos da raiz de D. amazonica aumentaram a mortalidade em todas as concentrações testadas e a concentração 8% da raiz de D. amazonica, apresentou menor número de ninfas. Todos os tratamentos testados apresentaram efeito deterrente. O período de 72 horas foi o que apresentou maior efeito dos extratos, das duas espécies estudadas sobre os insetos.

A abundância e o potencial inseticida de Derris amazonica e a necessidade de controle de Cerotoma arcuatus Olivier (Coleoptera: Chrysomelidae) na cultura do feijão-caupi (Vigna unguiculata L. Walp) estimularam a realização desta pesquisa, que objetivou avaliar a ação inseticida do extrato de D. amazonica a adultos de C. arcuatus em condições de laboratório. Os bioensaios testaram as vias de intoxicação por ingestão de folhas contaminadas, contato com superfície contaminada e aplicação tópica, com delineamento experimental inteiramente casualizado, com quatro repetições. Os valores de mortalidade e consumo foliar dos insetos foram submetidos à análise de regressão, sendo utilizada a análise de Probit para determinação das CL50, da DL50 e dos TL50. O extrato de D. amazonica, contendo 3,7% de rotenona, foi tóxico para adultos de C. arcuatus via ingestão de folhas contaminadas (CL50=15,14 µL do extrato.mL-1 de água), superfície contaminada (CL50=0,45 µL do extrato.cm-2) e aplicação tópica (DL50=1,44 µL do extrato.g-1 do inseto). Mortalidades de adultos de C. arcuatus superiores a 80% e os menores tempos letais médios foram obtidos na concentração de 5% (v v-1) do extrato em todos os bioensaios. O consumo foliar de adultos de C. arcuatus foi inversamente proporcional a concentração do extrato quando expostos por via de ingestão foliar ou aplicação tópica, sendo inclusive observada inibição da alimentação dos indivíduos. O extrato de D. amazonica é tóxico para C. arcuatus e inibe a alimentação dos insetos a partir da concentração de 1% (v v-1).The abundance and insecticidal potential of Derris amazonica in addition to need of controlling Cerotoma arcuatus for bean crop stimulated this research. The objective of this work was to evaluate insecticide action of the extract of D. amazonica to adults of C. arcuatus in laboratory conditions. The bioassays were carried out using three distend methodologies: leaf intake, contact in treated surface (filter paper) and topical application. A completed randomized experimental design was used with four replications. Mortality values and leaf consumption of the insects were subjected to regression analyses, being the Probit analyses used to determine of the i.e., LC50, LT50 and LD50. The extract of D. amazonica containing 3.7% of rotenone was toxic to adults C. arcuatus when exposed to treated leaves (LC50 = 15.14 µl.mL-1), treated surface (LC50 = 0.45 µl.cm-2) and subjected to topical exposure (LD50 = 1.44 µl.g-1). In all bioassays the adults mortality was higher than 80% with lower median lethal times obtained with 5% (v.v-1) concentrations of the extract. Leaf consumption by adults C. arcuatus was inversely proportional to the concentration of the extract when exposed by leaf intake or topical application, also being observed inhibition of feeding individuals. The extract of D. amazonica is toxic to C. arcuatus and inhibits the feeding of insects from the concentration of 1% (v v-1).

Foram realizados dois experimentos para avaliar o controle de endo e ectoparasitos de bovinos. No primeiro avaliou-se in vitro e, em animais experimentalmente infestados, o efeito da rotenona no carrapato Rhipicephalus(Boophilus) microplus e, no segundo, avaliou-se o efeito do pastejo rotacionado e de tratamentos contra endo e ectoparasitos na carga parasitária e no desenvolvimento de animais naturalmente parasitados. In vitro a rotenona mostrou ação acaricida nas larvas e nas teleóginas, e nas larvas nos animais estabulados. Três tratamentos com endectocida, no período seco, diminuiram significativamente a contagem de ovos por grama de fezes (OPG) e o número de teleóginas, e, aumentou significativamente o ganho médio de peso. Os animais tratados com uma aplicação de levamisol estavam nesse período com médias de OPG intermediárias e significativamente diferentes dos grupos controle e tratados com endectocida. O ganho de peso, entretanto, não diferiu significativamente do grupo controle. No período das águas, os animais tratados com fipronil estavam significativamente menos parasitados por teleóginas, mosca-dos-chifres e por larvas de Dermatobia hominis; e os tratados com rotenona. menos parasitados por mosca-dos-chifres que os animais controle. Diferentemente do esperado, os animais sob pastejo rotacionado estavam no período seco com OPG significativamente maior que os em sistema contínuo. Três tratamentos com endectocida, no período seco, e três tratamentos acaricida com fipronil, na estação chuvosa, diminuíram significativamente o OPG, o número de teleóginas e o de larvas de berne, e proporcionou um aumento significativo de 23 kg de peso vivo em relação aos animais não tratados.Practices for endo and ectoparasite control in beef cattle were evaluated in two independent experiments. First, the effects of rotenone® on Rhipicephalus (Boophilus) microplus ticks were evaluated in vitro and in experimentally infected calves. In the second trial, the effects of grazing systems associated with endo and ectoparasite treatments on parasite burden and weight gain of naturally parasited animals were evaluated. Rotenone showed acaricide action on larvae and engorged ticks during in vitro tests and on larvae in experimentally infected calves. Three treatments with endectocide decreased (P < .05) the number of EPG and ticks and increased (P < .05) the weight gain in the dry season. Animals treated with only one application of levamisole showed EPG intermediate and different (P < .05) from the groups treated with endectocide (lower) and control (higher) in the dry season, but the weight gain obtained with this treatment did not differ from the control group. During the raining season the animals treated with fipronil were significantly less parasited by horn fly, tick and larvae of Dermatobia hominis and the group treated with rotenone were significantly less parasited by horn fly in relation to control. Animals under rotational grazing showed significantly higher EPG than those under continuous grazing. Three treatments with endectocide in the dry season plus three acaricide treatments with fipronil in the raining season reduced EPG, tick, and screw worm larva counts, and provided a significant increase (23 kg) of live weight gain in relation to untreated animals.