behavioral-analysis-locomotor-dysfunction-drosophila-melanogaster-as

Behavioral Analysis of Locomotor Dysfunction in <em>Drosophila melanogaster</em> as a Readout for Neurotoxicity

This protocol presents a high-throughput, cost-effective method for assessing neurotoxicity in the fruit fly (Drosophila melanogaster) by quantifying ...

University of the Azores

Entomopathogenic nematodes are used as biological control agents against a broad range of insect pests. We ascribed the pathogenicity of these organisms to the excretory/secretory products (ESP) released by the infective nematode. Our group characterized different virulence factors produced by  that underlie its success as an insect pathogen. A novel ShK-like peptide (ScK1) from this nematode that presents high sequence similarity with the ShK peptide from a sea anemone was successfully produced recombinantly in . The secondary structure of ScK1 appeared redox-sensitive, exhibiting a far-UV circular dichroism spectrum consistent with an alpha-helical secondary structure. Thermal denaturation of the ScK1 allowed estimating the melting temperature to 59.2 ± 0.1 °C. The results from toxicity assays using  as a model show that injection of this peptide can kill insects in a dose-dependent manner with an LD of 16.9 µM per adult within 24 h. Oral administration of the fusion protein significantly reduced the locomotor activity of insects after 48 h ( < 0.05, Tukey's test). These data show that this nematode expresses insecticidal peptides with potential as next-generation insecticides.

A ShK-like Domain from  with Bioinsecticidal Potential.

The dataset presented here is an achievement of the H2020 European project "Integrated Pest Management of the Invasive Japanese Beetle,  (IPM-Popillia)". This project addresses the challenge of a new risk to plant health in Europe, the invasion of the Japanese beetle,  (Newman, 1838) (Coleoptera, Rutelidae) and provides an environmentally friendly IPM Toolbox to control the expanding pest populations across Europe. This study aims to present the records of terrestrial arthropod diversity with a special focus on four groups belonging to Carabids and Staphylinid beetles (Coleoptera), Opiliones and Anisolabididae (Dermaptera), collected with the potential to be used as biocontrol agents against  in future Integrated Pest Management programmes. A thorough sampling programme was conducted in maize and pasture fields in two Islands of the Azores (São Miguel and São Jorge) in the summer of 2022.

Monitoring Arthropods in maize and pasture fields in São Miguel and São Jorge Islands: IPM-Popillia Project.

We report the draft genome sequence of  strain ZMCS4, isolated from . The assembled genome consists of 4.5 Mbp, comprising 25 contigs and 4,128 coding sequences. This genome will provide insights into further studies on relevant CAZymes involved in the hydrolysis of algal cell walls.

Draft genome sequence of  strain ZMCS4, a putative CAZyme-producing bacteria isolated from the marine brown algae .

, commonly known as the Portuguese Man o' War, is one of the most venomous members of the Cnidaria yet is poorly understood. This article investigates the toxicity of  venom by assessing its behavioral and toxicological effects on . The venom administered orally revealed dose- and time-dependent mortality, with an LD50 of 67.4 μg per fly. At sublethal doses, the treated flies displayed uncoordinated movement and fell when attempting to climb. Real-time analysis of flies exposed to the venom revealed hyperexcitability followed by paralysis, with phenotypes similar to those observed in vertebrate models. The venom was shown to be non-thermolabile, as no significant differences in behavior and locomotion were observed between flies exposed to untreated or thermally treated venom. The circadian rhythm alterations, the enhanced light attraction, and the reduction in heat avoidance suggest altered neuronal function. This abnormal behavior indicates that the venom contains bioactive molecules, opening avenues for discovering new compounds with potential for pharmacological applications.

Revealing the Bioactivities of  Venom Using  as a Model.

Alzheimer's disease (AD), a multifactorial neurodegenerative disorder characterized by severe cognitive impairment, affects millions of people worldwide. However, AD therapy remains limited and mainly symptomatic-focused, with acetylcholinesterase (AChE) inhibitors being the major available drugs. Thus, AD is considered by the WHO as a disorder of public health priority. Among several strategies that have been identified to combat AD, the use of natural multi-target drug ligands (MTDLs) appears to be a promising approach. In this context, we previously found that the essential oils (EOs), obtained via hydrodistillation, from Azorean  sawdust (CJS) and resin-rich bark (CJRRB) were able to exert antioxidant activity via different mechanisms of action. Therefore, in the present work, these EOs were screened for their (i) in vitro anti-AChE and anti-butyrylcholinesterase (BChE) activities, evaluated by a modified Ellman's assay; (ii) in vitro anti-inflammatory potential, using the albumin denaturation method; and (iii) toxicity against . The CJRRB-EO exhibited both anti-AChE and anti-BChE activities (IC: 1935 and 600 µg/mL, respectively), whereas the CJS-EO only displayed anti-BChE activity, but it was 3.77-fold higher than that of the CJRRB-EO. Molecular docking suggested that α-pinene and ferruginol compounds contributed to the anti-AChE and anti-BChE activities, respectively. Moreover, the anti-inflammatory activity of the CJS-EO, the CJRRB-EO, and diclofenac was 51%, 70%, and 59% (at a concentration of only 2.21 μg/mL), respectively, with the latter two presenting comparable activity. Concerning the EOs' potential toxicity, the CJRRB-EO exhibited a lower effect than the CJS-EO (LC: 313 and 73 µg/mL, respectively). Overall, the EOs from C.  biomass residues, chiefly the CJRRB-EO, displayed antioxidant, anticholinesterase, and anti-inflammatory activities in a concentration-dependent manner. These properties demonstrate that these residues may be suitable natural MTDLs for AD complementary therapy when administered through aromatherapy, or, alternatively, could serve as low-cost sources of valuable ingredients, such as α-pinene.

Anticholinesterase and Anti-Inflammatory Activities of the Essential Oils of Sawdust and Resin-Rich Bark from Azorean  (Cupressaceae): In Vitro and In Silico Studies.

Article	Year
A ShK-like Domain from with Bioinsecticidal Potential. Toxins\| PubMed ID: 36356004	2022
Monitoring Arthropods in maize and pasture fields in São Miguel and São Jorge Islands: IPM-Popillia Project. Biodiversity data journal\| PubMed ID: 37840602	2023
Draft genome sequence of strain ZMCS4, a putative CAZyme-producing bacteria isolated from the marine brown algae . Microbiology resource announcements\| PubMed ID: 38534151	2024
Revealing the Bioactivities of Venom Using as a Model. Toxins\| PubMed ID: 39591246	2024
Anticholinesterase and Anti-Inflammatory Activities of the Essential Oils of Sawdust and Resin-Rich Bark from Azorean (Cupressaceae): In Vitro and In Silico Studies. International journal of molecular sciences\| PubMed ID: 39596392	2024

Jorge Frias

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