The Ameliorative Effect of Ashwagandha- Withania somnifera (L.) Dunal on park25 Induced Neurodegeneration in Drosophila melanogaster Parkinson’s Disease Model

Ashwagandha - Withania somnifera (L.) Dunal is a perennial shrub belonging to the family Solanaceae. Ashwagandha has been used for over 3000 years in traditional Indian Ayurveda for treatment of various neurological, and stress disorders. The root of Ashwagandha (ASH) is regarded as a tonic, aphrodisiac, narcotic, diuretic, anthelmintic, astringent, thermogenic and stimulant. Ashwagandha with other herbal decoctions was recognized to treat Kampavatha (Parkinson’s Disease) since 18th century. With this wide array of ethnopharmacological relevance, Ashwagandha has been recognized as one of the prominent complementary and alternative medicine to treat many neurodegenerative diseases like Alzheimer’s (AD) and Parkinson’s disease (PD). There is a prominent increase in the cases of AD and PD all over the world and it demands the requirement of complementary and alternative herbal remedies with no/minimal side effects. Many genetic factors are responsible for the onset and progression of PD. Loss-of-function mutations in the parkin gene are a major cause of early onset of autosomal recessive juvenile parkinsonism (AR-JP). Drosophila park25 loss of function mutants exhibit significantly increased number of mitochondria-endoplasmic reticulum contacts and a significantly decreased number of dopaminergic neurons in the adult brain which is the main cause of PD condition. Several studies have demonstrated the ability of Ashwagandha in imparting neuroprotection, improved locomotory ability, memory and learning abilities. The challenge lies in scrutinizing the mechanism and the pathways involved in the neuroprotective properties of this well-known herb. Here in our study, we test the possible neuroprotective effect of Ashwagandha on park25 mutants of Drosophila using lifespan analysis and climbing disability as a disease marker. Parkinson’s mimicking flies were administered with aqueous extraction of Ashwagandha-root mixed with the fly food and subjected to negative geotaxis assay. We observed that there is a prominent increase in the climbing ability in park25 treated flies compared to its age-matched untreated flies. This is the first report showing that, aqueous extraction of Ashwagandha-root extract was able to ameliorate the disease phenotype in the park25 Drosophila Parkinson’s disease model.

olf413 Gene Controls Taste Recognition, Preference and Feeding Activity in Drosophila melanogaster

Recognition and responsiveness to food taste becomes a crucial event in foraging and feeding behaviour of an organism. Adjusting the feeding behaviour through a sophisticated and robust taste system is critical to fulfil their nutritional needs and facilitate its survival in environment. Palatability of food sources depends on the sensory and motor cues provided by the brain, in co-ordination with the other body systems to enable decisive feeding. Drosophila melanogaster is an apt model organism to decipher these behavioural paradigms. Octopamine a neurotransmitter, is required in regulation of feeding behavioural responses. olf413, a paralogue of TH, is a gene predicted for its involvement in octopamine biosynthesis. The biological function of this gene is yet to be unravelled. Here we propose this gene function in taste recognition, food preference and feeding activity. We test the olf413 loss of function mutants for food preference between two fruit extracts using CAFE and horizontal box methods. In our study we have used olf413 gene disruption strain, olf413MI02014 homozygous and in transheterozygous condition with another allele isolated in our lab, olf413SG1.1. The results show that olf413 mutants display a severe phenotype in feeding behaviour and there is an allele specific phenotypic distinction between the two strains. Thus implying that olf413 gene function is required for taste recognition, starvation driven initiation and execution of feeding behaviour of the flies.

Exploring the mechanism of anti-hereditary Parkinson's disease of baicalein based on PINK1 RNAi Drosophila model / 药学学报

The aim of this study was to investigate the effect of baicalein on a Drosophila model of hereditary Parkinson's disease caused by gene mutations and to preliminarily elucidate the mechanism of baicalein in delaying hereditary Parkinson's disease. In this paper, PTEN-induced putative kinase 1 (PINK1)-RNAi Parkinson's Drosophila were used as the model group and wild-type Drosophila w1118 were used as the control group. Different doses of baicalein and Madopa were administered to the model group to observe their effects on the life span, motor ability, the abnormal rate of wings, dopamine content and dopaminergic neurons of PINK1-RNAi Parkinson's Drosophila and their effects on mitochondrial dysfunction including adenosine triphosphate (ATP), mitochondrial DNA (mtDNA) and reactive oxygen species (ROS) content. The results showed that the effective administration doses of baicalein were 0.8 mg·mL-1 for low concentration, 1.6 mg·mL-1 for medium concentration and 3.2 mg·mL-1 for high concentration, and the optimal administration dose of the positive drug Madopa was 0.1 μg·mL-1. Baicalein and Madopa could significantly improve the life span, exercise ability and reduce the abnormal rate of wings of PINK1-RNAi male Drosophila (P < 0.05), and low dose baicalein showed the best effect; baicalein could improve the loss of dopaminergic neurons, and the effects of low dose and high dose were the best, but Madopa showed no significant effect; baicalein and Madopa had no significant effect on dopamine content (P > 0.05). Baicalein and Madopa could increase the ATP content of PINK1-RNAi male Drosophila (P < 0.05), and low dose baicalein showed the best effect; middle dose baicalein could significantly increase the mtDNA content of PINK1-RNAi male Drosophila (P < 0.05), but Madopa had no significant effect; baicalein and Madopa had no significant effect on ROS content (P > 0.05).

The regulatory relationship between RagA and Nprl2 in Drosophila gut development / 生物工程学报

The gastrointestinal tract is the largest digestive organ and the largest immune organ and detoxification organ, which is vital to the health of the body. Drosophila is a classic model organism, and its gut is highly similar to mammalian gut in terms of cell composition and genetic regulation, therefore can be used as a good model for studying gut development. target of rapmaycin complex 1 (TORC1) is a key factor regulating cellular metabolism. Nprl2 inhibits TORC1 activity by reducing Rag GTPase activity. Previous studies have found that nprl2 mutated Drosophila showed aging-related phenotypes such as enlarged foregastric and reduced lifespan, which were caused by over-activation of TORC1. In order to explore the role of Rag GTPase in the developmental defects of the gut of nprl2 mutated Drosophila, we used genetic hybridization combined with immunofluorescence to study the intestinal morphology and intestinal cell composition of RagA knockdown and nprl2 mutated Drosophila. The results showed that RagA knockdown alone could induce intestinal thickening and forestomach enlargement, suggesting that RagA also plays an important role in intestinal development. Knockdown of RagA rescued the phenotype of intestinal thinning and decreased secretory cells in nprl2 mutants, suggesting that Nprl2 may regulate the differentiation and morphology of intestinal cells by acting on RagA. Knockdown of RagA did not rescue the enlarged forestomach phenotype in nprl2 mutants, suggesting that Nprl2 may regulate forestomach development and intestinal digestive function through a mechanism independent of Rag GTPase.

Resveratrol and Sir2 Reverse Sleep and Memory Defects Induced by Amyloid Precursor Protein / 神经科学通报·英文版

Resveratrol (RES), a natural polyphenolic phytochemical, has been suggested as a putative anti-aging molecule for the prevention and treatment of Alzheimer's disease (AD) by the activation of sirtuin 1 (Sirt1/Sir2). In this study, we tested the effects of RES and Sirt1/Sir2 on sleep and courtship memory in a Drosophila model by overexpression of amyloid precursor protein (APP), whose duplications and mutations cause familial AD. We found a mild but significant transcriptional increase of Drosophila Sir2 (dSir2) by RES supplementation for up to 17 days in APP flies, but not for 7 days. RES and dSir2 almost completely reversed the sleep and memory deficits in APP flies. We further demonstrated that dSir2 acts as a sleep promotor in Drosophila neurons. Interestingly, RES increased sleep in the absence of dSir2 in dSir2-null mutants, and RES further enhanced sleep when dSir2 was either overexpressed or knocked down in APP flies. Finally, we showed that Aβ aggregates in APP flies were reduced by RES and dSir2, probably via inhibiting Drosophila β-secretase (dBACE). Our data suggest that RES rescues the APP-induced behavioral deficits and Aβ burden largely, but not exclusively, via dSir2.

Direction Selectivity of TmY Neurites in Drosophila / 神经科学通报·英文版

The perception of motion is an important function of vision. Neural wiring diagrams for extracting directional information have been obtained by connectome reconstruction. Direction selectivity in Drosophila is thought to originate in T4/T5 neurons through integrating inputs with different temporal filtering properties. Through genetic screening based on synaptic distribution, we isolated a new type of TmY neuron, termed TmY-ds, that form reciprocal synaptic connections with T4/T5 neurons. Its neurites responded to grating motion along the four cardinal directions and showed a variety of direction selectivity. Intriguingly, its direction selectivity originated from temporal filtering neurons rather than T4/T5. Genetic silencing and activation experiments showed that TmY-ds neurons are functionally upstream of T4/T5. Our results suggest that direction selectivity is generated in a tripartite circuit formed among these three neurons-temporal filtering, TmY-ds, and T4/T5 neurons, in which TmY-ds plays a role in the enhancement of direction selectivity in T4/T5 neurons.

Neuroprotective effect of ginsenoside Re on drosophila model of Parkinson's disease / 中国中药杂志

This study aims to explore the neuroprotective mechanism of ginsenoside Re(GS-Re) on drosophila model of Parkinson's disease(PD) induced by rotenone(Rot). To be specific, Rot was used to induce PD in drosophilas. Then the drosophilas were grouped and respectively treated(GS-Re: 0.1, 0.4, 1.6 mmol·L~(-1); L-dopa: 80 μmol·L~(-1)). Life span and crawling ability of drosophilas were determined. The brain antioxidant activity [content of catalase(CAT), malondialdehyde(MDA), reactive oxygen species(ROS), superoxide dismutase(SOD)], dopamine(DA) content, and mitochondrial function [content of adenosine triphosphate(ATP), NADH:ubiquinone oxidoreductase subunit B8(NDUFB8) Ⅰ activity, succinate dehydrogenase complex, subunit B(SDHB) Ⅱ activity] were detected by enzyme-linked immunosorbent assay(ELISA). The number of DA neurons in the brains of drosophilas was measured with the immunofluorescence method. The levels of NDUFB8 Ⅰ, SDHB Ⅱ, cytochrome C(Cyt C), nuclear factor-E2-related factor 2(Nrf2), heme oxygenase-1(HO-1), B-cell lymphoma/leukemia 2(Bcl-2)/Bcl-2-assaciated X protein(Bax), and cleaved caspase-3/caspase-3 in the brain were detected by Western blot. The results showed that model group [475 μmol·L~(-1) Rot(IC_(50))] demonstrated significantly low survival rate, obvious dyskinesia, small number of neurons and low DA content in the brain, high ROS level and MDA content, low content of SOD and CAT, significantly low ATP content, NDUFB8 Ⅰ activity, and SDHB Ⅱ activity, significantly low expression of NDUFB8 Ⅰ, SDHB Ⅱ, and Bcl-2/Bax, large amount of Cyt C released from mitochondria to cytoplasm, low nuclear transfer of Nrf2, and significantly high expression of cleaved caspase-3/caspase-3 compared with the control group. GS-Re(0.1, 0.4, and 1.6 mmol·L~(-1)) significantly improved the survival rate of PD drosophilas, alleviated the dyskinesia, increased DA content, reduced the loss of DA neurons, ROS level, and MDA content in brain, improved content of SOD and CAT and antioxidant activity in brain, maintained mitochondrial homeostasis(significantly increased ATP content and activity of NDUFB8 Ⅰ and SDHB Ⅱ, significantly up-regulated expression of NDUFB8 Ⅰ, SDHB Ⅱ, and Bcl-2/Bax), significantly reduced the expression of Cyt C, increased the nuclear transfer of Nrf2, and down-regulated the expression of cleaved caspase-3/caspase-3. In conclusion, GS-Re can significantly relieve the Rot-induced cerebral neurotoxicity in drosophilas. The mechanism may be that GS-Re activates Keap1-Nrf2-ARE signaling pathway by maintaining mitochondrial homeostasis, improves antioxidant capacity of brain neurons, then inhibits mitochondria-mediated caspase-3 signaling pathway, and the apoptosis of neuronal cells, thereby exerting the neuroprotective effect.

Based on the metabolic mechanism of UHPLC-Q-Exactive-MS Hippocampus to delay the aging of Drosophila melanogaster / 药学学报

Based on the UHPLC-Q-Exactive-MS metabonomics technology, the effect of Hippocampus kuda Bleeker on the life span of Drosophila melanogaster was studied, and the change rule of endogenous metabolites in the aging process of Drosophila melanogaster after the intervention of Hippocampus kuda Bleeker japonicus was explored to clarify the anti-aging mechanism of Hippocampus. The natural aging model of Drosophila melanogaster was used. Different doses of raw Hippocampus and fried Hippocampus were given to observe the effects on the life span, climbing ability, sexual activity, and antioxidant enzyme activity of Drosophila melanogaster. Based on UHPLC-Q-Exactive-MS metabolomics technology, the metabolic profile of the aging Drosophila melanogaster was analyzed using metabonomics technology to explore the mechanism of Hippocampus kuda Bleeker delaying the aging of Drosophila melanogaster. The results showed that raw Hippocampus and crispy Hippocampus (1, 4 mg·mL-1) could significantly prolong the average life span, median life span and maximum life span of male fruit flies, and significantly improve the climbing ability and sexual vitality of fruit flies. Catalase (CAT) and aldehyde content were increased, while malonaldehyde (MDA) content was decreased. Through metabonomics technology, it was identified that the Hippocampus can significantly recall 16 metabolites and participate in the biosynthesis of phenylalanine, tyrosine and tryptophan, starch and sucrose metabolism, tyrosine metabolism, cysteine and methionine metabolism, and histidine metabolism. The anti-aging mechanism is related to amino acid metabolism and sugar metabolism, which provides a substantial scientific basis for the development and utilization of Hippocampus and clarifying its role in senile diseases. The animal experiment of this study was approved by the Ethics Committee of Shanxi University (approval number: SXULL2021028).

Effects of Dolutegravir (DTG) on Survival, Pupariation and Emergence in Drosophila melanogaster: The Rescue Role of Brassica oleracea

The study aimed at determining the protective role of Brassica oleracea on dolutegravir-induced changes in Pupariation and Emergence of Drosophila melanogaster. D. melanogaster aged 3-5 days old were exposed to different concentrations (0.5 to 4 mg/ 5 g diet) of dolutegravir and B. oleracea extract (7.5–1000 mg/5 g diet) for 7 days to determine the lethal concentration (LC50). D. melanogaster were then exposed to the extract (50, 100, 200, and 400 mg/5 g diet) and controls (diet alone and vitamin C) to assess their effects on pupariation and emergence. A 14-day assay was also performed to evaluate the effect of the extract and toxicant (dolutegravir) on fly survival. The result showed a dose-dependent significant decrease (P < 0.05) and a dose-dependent significant increase (P < 0.05) in survival for D. melanogaster exposed to dolutegravir and the extract respectively, when compared to the control group. Results showed a delay in pupariation and decrease in mean pupariation in flies exposed to dolutegravir alone. An improvement in the same parameters was observed in D. melanogaster pre-treated with the extract before exposure to dolutegravir. D. melanogaster pre-treated with 200 and 400 mg extract per 5 g diet showed emergence that was comparable to those in the control groups. A significant decrease (P < 0.05) was observed in the groups exposed to 50 and 100 mg extract per 5 g diet, suggesting no protection at these doses. This study concludes that B. oleracea leaf extract, at certain concentrations, is able to protect against dolutegravir-induced changes in pupariation and emergence in D. melanogaster.

Biological toxicity of Ruta graveolens essential oil against three species of diptera Drosophila melanogaster, Culex pipiens and Culiseta longiareolata

Background & objectives: Recently, the use of biodegradable and environment friendly plant-based bioinsecticides has received a great deal of attention from researchers to control insect disease vectors. The aim of this research is to determine the larvicidal efficacy of Ruta graveolens essential oil against third instar larvae of two species of mosquito (Culex pipiens and Culiseta longiareolata) and a biological model Drosophila melanogaster. Methods: Culiseta longiareolata and Culex pipiens larvae were collected from untreated areas located in Tebessa and Drosophila melanogaster, the wild strain collected from rotten apples in the Tebessa region. Ruta graveolens essential oil has been tested at different concentrations between 2.5µL/mL and 140µL/mL against third instar larvae of the three species under standard laboratory conditions according to the recommendations from the Word Health Organization. The effects were examined on mortality, growth and the main components (proteins, carbohydrates, lipids). Results: The essential oil showed larvicidal activity with LC50 and LC90 values (10.85µL/mL, 70.95µL/mL and 39.41µL/mL), (26.5µL/mL, 144.5µL/mL and 89.57µL/mL) against third instar larvae of Drosophila melanogaster, Culex pipiens and Culiseta longiareolata respectively. In addition, it disrupted the growth and several morphological malformations were observed. It also affected growth and the main components (proteins, carbohydrates, lipids). Interpretation & conclusion: The essential oil affected growth and energy reserves for all three species. The results indicated that the essential oil of Ruta graveolens has good potential as a source of natural larvicides.

Avaliação do efeito carcinogênico do bromazepam em Drosophila melanogaster / Evaluation of carcinogen bromazepam effect in Drosophila melanogaster

Introdução: embora o câncer seja um dos maiores problemas de saúde pública enfrentados mundialmente, diversas substâncias presentes no meio, como os fármacos, não estão muito bem elucidadas sobre seu possível potencial carcinogênico. Entre eles, estão os benzodiazepínicos, fármacos que possuem crescente aumento do consumo desde o século XX e, principalmente, na segunda década do século XXI, por suas ações ansiolíticas, sedativas e anticonvulsivantes. Objetivo: avaliar o efeito carcinogênico do bromazepam por meio do teste para detecção de tumores epiteliais (ETT) em Drosophila melanogaster. Metodologia: para realização do ETT foram utilizadas duas linhagens mutantes de D. melanogaster: wts (fêmeas) e mwh (machos). As larvas descendentes desse cruzamento foram tratadas isoladamente com cinco concentrações de bromazepam, sendo elas: 0,0375; 0,075; 0,15; 0,30 e 0,60 mM. A Doxorrubicina foi utilizada como controle positivo e a água ultrapura como controle negativo. Após tratamento, coleta e armazenamento, as moscas foram analisadas, identificando-se as frequências tumorais, por região corporal, em cada concentração testada. Resultados: o bromazepam não apresentou efeito carcinogênico em nenhuma das concentrações experimentadas neste estudo, não havendo diferença estatisticamente significativa nas frequências tumorais observadas nos indivíduos tratados com bromazepam quando comparadas à frequência obtida nos indivíduos tratados com o controle negativo. Conclusão: Nas presentes condições experimentais, o bromazepam não apresentou atividade carcinogênica, no entanto, há a necessidade de novos estudos, com diferentes metodologias e diferentes organismos testes, para a maior compreensão da ação do bromazepam no organismo.

Introduction: although cancer is one of the biggest public health problems faced worldwide, several substances present in the environment, such as drugs are not very well understood about its possible carcinogenic potential. Among them are benzodiazepines, drugs that have increased their consumption since the 20th century and, mainly, in the second decade of the 21st century, due to their anxiolytic, sedative and anticonvulsant actions. Objective: Evaluate the carcinogenic effect of bromazepam through the test to detect epithelial tumor clones (ETT) in Drosophila melanogaster. Methodology: to perform the ETT, two mutant strains of D. melanogaster were used: wts (female) and mwh (male). The descending larves of this cross were treated separately with five concentrations of bromazepam, namely: 0.0375; 0.075; 0.15; 0.30 and 0.60 mM. Doxorubicin was used as a positive control and ultrapure water as a negative control. After treatment, collection and storage, the flies were analyzed, identifying the tumor frequencies, by body region, at each concentration tested. Results: bromazepam did not have a carcinogenic effect at any of the concentrations experienced in this study, with no statistically significant difference in tumor frequencies observed in individuals treated with bromazepam when compared to the frequency obtained in individuals treated with the negative control. Conclusion: In the present experimental conditions, bromazepam did not show carcinogenic activity, however, there is a need for further studies with different methodologies and different test organisms to better understand the action of bromazepam in the body.

Estudo do potencial de reposicionamento do composto auranofina no controle de infecções por Candida albicans / Study on the potential for the repositioning of auranofin in the control of Candida albicans infections

A ocorrência crescente de resistência antifúngica, a toxicidade, além do pequeno espectro de ação dos antifúngicos convencionais, limita o número de alternativas terapêuticas para doenças causadas por leveduras do gênero Candida. Uma das frentes de pesquisa é a proposta de novos usos para drogas existentes chamada de reposicionamento, que diminui o tempo e esforço na busca de novos compostos eficazes. Neste contexto, o presente estudo tem como objetivo avaliar o potencial antifúngico e os mecanismos de ação do composto auranofina contra a espécie Candida albicans, além da toxicidade in vivo. Foram utilizadas cepas padrões de C. albicans (SC5314, ATCC 18804) e as concentrações inibitória mínima (CIM) e fungicida mínima (CFM) foram determinadas. Os mecanismos de ação dos compostos foram avaliados sobre a estrutura celular de C. albicans, com verificação de alterações na morfologia, na parede celular, sobre os fatores de virulência de C. albicans, como transição levedura-hifa e produção de exoenzimas, além do efeito do composto sobre o metabolismo de C. albicans e efeito antifúngico sob condições de estresse osmótico. Para avaliação da toxicidade das concentrações efetivas de auranofina in vivo, foi utilizado o modelo invertebrado, Drosophila melanogaster. Os dados obtidos no ensaio de transição levedura-hifa foram avaliados pelos testes ANOVA e de Tukey e os testes Kruskal-Wallis e de Dunn. foram utilizados na análise do efeito de auranofina sobre o metabolismo fúngico. O nível de significância para todos os testes foi de 5%. Foram verificadas concentrações inibitória e fungicida de auranofina sobre C. albicans. Apesar da ausência de efeitos sobre fatores de virulência, auranofina causou redução no metabolismo fúngico e no crescimento fúngico sob estresse osmótico, sugerindo, nesse caso, um possível efeito direto ou indireto na membrana celular fúngica. Além disso, nas concentrações efetivas não foi observada toxicidade relevante in vivo. Os resultados demonstraram, portanto, que auranofina tem potencial para seu reposicionamento como antifúngico, no entanto, mais estudos são necessários para mais esclarecimentos e utilização adequada do medicamento (AU).

The increasing occurrence of antifungal resistance, toxicity, in addition to the small spectrum of action of conventional antifungals, limits the number of therapeutic alternatives for diseases caused by yeasts of the genus Candida. One of the research fronts is the proposal of new uses for existing drugs called repositioning, which reduces the time and effort in the search for new effective compounds. In this context, the present study aims to evaluate the antifungal potential and mechanisms of action of the auranofin compound against Candida albicans, in addition to in vivo toxicity. Standard strains of C. albicans (SC5314, ATCC 18804) were used and minimum inhibitory concentration (MIC) and minimum fungicide concentration (MFC) were determined. The mechanisms of action of the compounds were evaluated on the cellular structure of C. albicans, with verification of changes in morphology, in the cell wall, on the virulence factors of C. albicans, such as yeast-hypha transition and production of exoenzymes, in addition to the effect of the compound on the metabolism of C. albicans and antifungal effect under osmotic stress conditions. To evaluate the toxicity of effective concentrations of auranofin in vivo, the invertebrate model, Drosophila melanogaster, was used. The data obtained in the yeast-hypha transition assay were evaluated by the ANOVA and Tukey tests and the KruskalWallis and Dunn tests. were used to analyze the effect of auranofin on fungal metabolism. The significance level for all tests was 5%. Inhibitory and fungicidal concentrations of auranofin were verified on C. albicans. Despite the absence of effects on virulence factors, auranofin caused a reduction in fungal metabolism and fungal growth under osmotic stress, suggesting, in this case, a possible direct or indirect effect on the fungal cell membrane. Furthermore, at effective concentrations, no relevant in vivo toxicity was observed. The results showed, therefore, that auranofin has the potential for its repositioning as an antifungal, however, more studies are needed for further clarification and proper use of the drug (AU).

Efeito modulador do Firocoxib (Previcox®) sobre a ação carcinogênica da doxorrubicina por meio do teste de tumores epiteliais (ETT) em Drosophila melanogaster / Modulatory effect of Firocoxib (Previcox®) on the carcinogenic action of doxorubicin through the epithelial tumor teste (TTE) in Drosophila melanogaster

Introdução: a superexpressão da COX-2 relaciona-se com o aumento da produção de fatores de crescimento vascular e como consequência, com o desenvolvimento tumoral. O Firocoxib é um anti-inflamatório não esteroidal utilizado para inflamação associada à osteoartrite em cães. É o inibidor mais seletivo da COX-2, reduzindo eficientemente a ação desta enzima. Estudos indicam os benefícios do Firocoxib na terapia antineoplásica. Objetivo: este trabalho objetivou avaliar o efeito modulador do Firocoxib sobre a ação da doxorrubicina (DXR) por meio do teste de tumores epiteliais (ETT) em Drosophila melanogaster. Metodologia: foram preparadas três concentrações de Firocoxib: 2,5; 5 e 10 mg/mL, utilizadas isoladamente e em associação à doxorrubicina. O tratamento ocorreu com larvas de D. melanogaster descendentes do cruzamento de fêmeas wts/TM3 com machos mwh/mwh. Resultados: os resultados sugerem que o Firocoxib possui atividade moduladora sobre a ação carcinogênica da DXR, pois houve redução significativa nas frequências tumorais dos indivíduos tratados com diferentes concentrações de Firocoxib em cotratamento com a doxorrubicina quando comparadas à frequência tumoral do controle positivo. Conclusão: conclui-se que, nas presentes condições experimentais, o Firocoxib reduziu a frequência de tumores induzidos pela doxorrubicina em D. melanogaster.

Introduction: COX-2 overexpression is related to increased production of vascular growth factors and, as a consequence, to tumor development. Firocoxib is a non-steroidal anti-inflammatory drug used for inflammation associated with osteoarthritis in dogs. It is the most selective inhibitor of COX-2, efficiently reducing the action of this enzyme. Studies indicate the benefits of Firocoxib in anticancer therapy. Objective: this study aimed to evaluate the modulatory effect of Firocoxib on the action of doxorubicin (DXR) by means of the epithelial tumor test (ETT) in Drosophila melanogaster. Methodology: three concentrations of Firocoxib were prepared: 2.5; 5 and 10 mg/mL, used alone and in association with doxorubicin. The treatment occurred with D. melanogaster larvae descended from the crossing of wts/TM3 females with mwh/mwh males. Results: the results suggest that Firocoxib has modulating activity on the carcinogenic action of DXR, as there was a significant reduction in tumor frequencies in individuals treated with different concentrations of Firocoxib in co-treatment with doxorubicin when compared to the tumor frequency of the positive control. Conclusion: it is concluded that, under the present experimental conditions, Firocoxib reduced the frequency of tumors induced by doxorubicin in D. melanogaster.

Axonemal Dynein DNAH5 is Required for Sound Sensation in Drosophila Larvae / 神经科学通报·英文版

Chordotonal neurons are responsible for sound sensation in Drosophila. However, little is known about how they respond to sound with high sensitivity. Using genetic labeling, we found one of the Drosophila axonemal dynein heavy chains, CG9492 (DNAH5), was specifically expressed in larval chordotonal neurons and showed a distribution restricted to proximal cilia. While DNAH5 mutation did not affect the cilium morphology or the trafficking of Inactive, a candidate auditory transduction channel, larvae with DNAH5 mutation had reduced startle responses to sound at low and medium intensities. Calcium imaging confirmed that DNAH5 functioned autonomously in chordotonal neurons for larval sound sensation. Furthermore, disrupting DNAH5 resulted in a decrease of spike firing responses to low-level sound in chordotonal neurons. Intriguingly, DNAH5 mutant larvae displayed an altered frequency tuning curve of the auditory organs. All together, our findings support a critical role of DNAH5 in tuning the frequency selectivity and the sound sensitivity of larval auditory neurons.

First report of colored pan traps to capture Drosophilidae (Diptera)

ABSTRACT The use of robust sample methodologies to estimate the highest number of species with different ecological requirements and traits is essential to the knowledge construction of the biodiversity and to establish wildlife assessment and monitoring programs. Our aims were to study the performance of colored pan traps in the capture of Drosophilidae (Diptera), a method never used for sampling this taxon. During six months, colored pan traps (blue, yellow and white) were tested in three areas in Southern Brazil. We captured 375 individuals of 30 species belonging to four genera of Drosophilidae. The most abundant species were Drosophila lutzii (n=215) p=0.58, Scaptomyza sp. (n=55) p=0.15 and D. bromelioides (n=17) p=0.04, all of them, anthophilous species. All colored pan traps captured a high quantify species of Drosophilidae, mainly anthophilous species.

Protective Effect of Alkaloid-rich Extract of Brimstone Tree (Morinda lucida) on Neurotoxicity in the Fruit-fly (Drosophila melanogaster) Model

Afr. J. Biomed. Res. Vol. 24 (May, 2021); 257- 263 Research Article Protective Effect of Alkaloid-rich Extract of Brimstone Tree (Morinda lucida) on Neurotoxicity in the Fruit-fly (Drosophila melanogaster) Model Nwanna E.E. Functional Food, Nutraceutical and Phytomedicine unit Department of Biochemistry, Federal University of Technology Akure PMB 704, Nigeria ABSTRACT Brimstone plant is one of the medicinal plants found in Nigeria used in fore-lore medicine with little scientific information on its alkaloid constituents. This study was aimed at investigating the effect of alkaloid-rich compounds from the plant in manganese- induced (MgCl2) neurotoxicity in the fruit fly. In addition, alkaloid compounds will be characterized using gas chromatograph coupled with flame ionization detector (GC-FID). Alkaloid-rich extract was prepared by solvent extraction method, fruit flies were pre-treated with the extract (0.5 ­ 1.0mg/ml) in a fortified diet before induction with MgCl2. The survival rate and negative geotaxis were observed. Thereafter, the activity of acetylcholinesterase (AChE) enzyme, antioxidantive potentials in in -vivo reactive oxygen species (ROS) thiobarbituric acid reactive species (TBARS), total thiol content, nitric oxide (NO*), hydroxyl oxide (OH*) scavenging ability, ferric reducing antioxidant property (FRAP) and 2, 2'-azino-bis (3-ethylbenzthiazoline-6- sulphonic acid) (ABTs*) radical scavenging ability were carried out on the flies' homogenate. Results obtained revealed that the alkaloid-rich extract regulated the neuro-protective activity of AchE, reduced the reactive oxygen species level in the induced flies with an increased in antioxidantive potential, higher survival rate and increases in the life span of the flies with 50% reduction in the mortality rate. The GC-MS showed a total of (1.55/100mg) of different plant-derived alkaloids such as dicentrine, atropine, aporphine. These alkaloids-rich compounds were found to have anti-oxidative, anti-nociceptive, anti-inflammatory and anti- cholinergic activities. In conclusion, this study suggests that alkaloids from brimstone plant could be the reason for the observed biological activities for the prevention of neuronal related complications.

Evaluation of Drosophila chromosomal segments proposed by means of simulations of possessing hybrid sterility genes from reproductive isolation

In heterozygote state, we interogressed three chromosomal segments of Drosophila koepferae in D. buzzatii. The effect of each introgression was evaluated in the fertility of the segmental males, quantifying the amount of offspring produced. Through specific crosses method, we generated Drosophila segmental isolines carrying specific chromosomal introgression segments. The introgressions were monitored cytogenetically by the method of molecular markers of chromosomal asynapsis. The statistical analysis showed that none of the three segments evaluated, introgressed individually or in pairs, as well as cis or trans, do not produce sterility in the segmental males, as determined by the normal productions of offspring. Additional introgressions using other larger segments show that when the introgressions reach a minimum size of 31.15%, they produce sterility. It is concluded that the hybrid sterility genes present in the three segments evaluated did not act in strong epistasis, but show a pattern of gradual additive behaviour by requiring a minimum threshold size to produce sterility. Finally, we also isolated the smallest introgressing segment that has been reported for these species (2.19%), and for the first time we have managed to place it in homozygous state (data not shown), so we are now in the process of evaluating the ability to these segments in homozygous state.

Safety evaluation of polysaccharides isolated from the water extract of Argemone mexicana L. (Papaveraceae) in Drosophila melanogaster

Recently, the plant polysaccharides have attracted attention due to their important bioactivities. The literature hasshown several pharmacological activities of Argemone mexicana extracts and its components but very few dataon its polysaccharides. The current study aimed to evaluate the safety of polysaccharides from A. mexicana. Fivepolysaccharides [High molecular weight (polysaccharide fraction) of the water extract from Argemone mexicana 1( HMAm1), HMAm2, HMAm3, HMAmA1, and HMAmA2] were fractionated from A. mexicana aerial parts by usingaccelerated solvent extractor procedure followed by ion exchange chromatography of the water decoction extract.The safety assay was carried out using Drosophila melanogaster exposed to the polysaccharides at 12.5 and 25 µg/ml for 72 hours against a negative control (1% DMSO). After the exposure period, the survival rate and the locomotorcapacity of flies were determined. At the end of 72 hours of treatment, all polysaccharide fractions at both dosespresented a survival percent of more than 94%. In addition, these polysaccharide fractions affected very little thelocomotor performance of the flies. At both doses, HMAm2 presented the highest safety for the flies, while HMAm3was the least. These findings revealed that polysaccharides from A. mexicana are nontoxic.

Drosophila ananassae: a species characterized by spontaneous male recombination in appreciable frequency

Mutation and recombination are primarily responsible for generating the genetic variability in natural populations of microorganisms, plant and animal species including humans. Upon such genetic variations, elemental forces of evolution such as natural selection, random genetic drift and migration operate to bring about micro-evolutionary changes. Recombination or crossing-over produces new combinations of genes due to interchange of corresponding segments between nonsister chromatids of homologous chromosomes, thus, it is an important evolutionary factor. Since the time of T. H. Morgan, Drosophila has been subjected to extensive investigations on crossing over while employing a number of markers, which were used for gene mapping. Interestingly, recombination occurs in females of D. melanogaster but not in males. Later on, male crossing over was investigated in various species and its occurrence was reported in D. melanogaster, D. ananassae, D. simulans, D. willistoni, D. littoralis and D. bipectinata. Recombination occurs at very low rate in all these species except for D. ananassae, which shows spontaneous male crossing over in appreciable frequency, which is meiotic in origin. This unusual phenomenon in D. ananassae is influenced by various genetic factors as well as it shows strain variation as far as frequency of male recombination is concerned. Further, the presence of chiasmata during meiosis in males at a frequency capable of accounting for the observed recombination frequency extends evidence for meiotic origin of recombination in males of D. ananassae.

Genomic organization of Polycomb Response Elements and its functional implication in Drosophila and other insects

The epigenetic memory is an essential aspect of multicellular organisms to maintain several cell types and their geneexpression pattern. This complex process uses a number of protein factors and specific DNA elements within thedevelopmental cues to achieve this. The protein factors involved in the process are the Polycomb group (PcG)members, and, accordingly, the DNA sequences that interact with these proteins are called Polycomb ResponseElements (PREs). Since the PcG proteins are highly conserved among higher eukaryotes, including insects, andfunction at thousands of sites in the genomes, it is expected that PREs may also be present across the genome. However,the studies on PREs in insect species, other thanDrosophila, is currently lacking.We took a bioinformatics approach todevelop an inclusive PRE prediction tool, ‘PRE Mapper’, to address this need. By applying this tool on the Drosophilamelanogaster genome, we predicted[20,000 PREs. When compared with the available PRE prediction methods, thistool shows far better performance by correctly identifying the in vivo binding sites of PcG proteins, identified bygenome-scale ChIP experiments. Further analysis of the predicted PREs shows their cohabitation with chromatindomain boundary elements at several places in the Drosophila genome, possibly defining a composite epigeneticmodule. We analysed 10 insect genomes in this context and find several conserved features in PREs across the insectspecies with some variations in their occurrence frequency. These analyses leading to the identification of PRE in insectgenomes contribute to our understanding of epigenetic mechanisms in these organisms.