Pesticide-Induced Inflammation at a Glance.

The increasing number of studies reporting the risks of the exposure to pesticides aligned with the intensified use of such hazardous chemicals has emerged as a pressing contemporary issue, notably due to the potential effects to both the environment and human health. Pesticides, while broadly applied in modern agriculture for pest control and crop protection, have raised concerns due to their unintended effects on non-target organisms. The immune system exerts a key role in the protection against the exposome, which could result in cellular imbalances and tissue damage through the inflammatory response. Pesticides, which encompass a diverse array of chemicals, have been linked to inflammation in experimental models. Therefore, the aim of this review is to discuss the increasing concern over the risks of pesticide exposure focusing on the effects of various chemical classes on inflammation by covering, as broadly as possible, different experimental approaches as well as the multiple or co-exposure of pesticides. Overall, pesticides potentially induce inflammation in different experimental models, manifested through skin irritation, respiratory impairment, or systemic effects. The connection between pesticides and inflammation highlights the importance of proper handling and regulation of these substances and underscores the need for research into safer and sustainable practices to reduce our reliance on synthetic pesticides and fertilizers.

Revisiting Retinal Degeneration Hallmarks: Insights from Molecular Markers and Therapy Perspectives.

Visual impairment and blindness are a growing public health problem as they reduce the life quality of millions of people. The management and treatment of these diseases represent scientific and therapeutic challenges because different cellular and molecular actors involved in the pathophysiology are still being identified. Visual system components, particularly retinal cells, are extremely sensitive to genetic or metabolic alterations, and immune responses activated by local insults contribute to biological events, culminating in vision loss and irreversible blindness. Several ocular diseases are linked to retinal cell loss, and some of them, such as retinitis pigmentosa, age-related macular degeneration, glaucoma, and diabetic retinopathy, are characterized by pathophysiological hallmarks that represent possibilities to study and develop novel treatments for retinal cell degeneration. Here, we present a compilation of revisited information on retinal degeneration, including pathophysiological and molecular features and biochemical hallmarks, and possible research directions for novel treatments to assist as a guide for innovative research. The knowledge expansion upon the mechanistic bases of the pathobiology of eye diseases, including information on complex interactions of genetic predisposition, chronic inflammation, and environmental and aging-related factors, will prompt the identification of new therapeutic strategies.

Pesticides and Their Impairing Effects on Epithelial Barrier Integrity, Dysbiosis, Disruption of the AhR Signaling Pathway and Development of Immune-Mediated Inflammatory Diseases.

The environmental and occupational risk we confront from agricultural chemicals increases as their presence in natural habitats rises to hazardous levels, building a major part of the exposome. This is of particular concern in low- and middle-income countries, such as Brazil, known as a leading producer of agricultural commodities and consumer of pesticides. As long as public policies continue to encourage the indiscriminate use of pesticides and governments continue to support this strategy instead of endorsing sustainable agricultural alternatives, the environmental burden that damages epithelial barriers will continue to grow. Chronic exposure to environmental contaminants in early life can affect crucial barrier tissue, such as skin epithelium, airways, and intestine, causing increased permeability, leaking, dysbiosis, and inflammation, with serious implications for metabolism and homeostasis. This vicious cycle of exposure to environmental factors and the consequent damage to the epithelial barrier has been associated with an increase in immune-mediated chronic inflammatory diseases. Understanding how the harmful effects of pesticides on the epithelial barrier impact cellular interactions mediated by endogenous sensors that coordinate a successful immune system represents a crucial challenge. In line with the epithelial barrier hypothesis, this narrative review reports the available evidence on the effects of pesticides on epithelial barrier integrity, dysbiosis, AhR signaling, and the consequent development of immune-mediated inflammatory diseases.

High Melanin Content in Melanoma Cells Contributes to Enhanced DNA Damage after Rose Bengal Photosensitization.

Melanoma is a type of tumor that originates from melanocytes. Irradiation of melanin with UVA and visible light can produce reactive oxygen species (ROS) such as singlet molecular oxygen (1 O2 ). The objective of this study was to examine DNA damage in melanoma cells (B16-F10) with different melanin contents, subjected to 1 O2 generation. To this end, we used the photosensitizer Rose Bengal acetate (RBAc) and irradiation with visible light (526 nm) (RBAc-PDT). We used the modified comet assay with the repair enzymes hOGG1 and T4 endonuclease V to detect the DNA damage associated with 8-oxo-7,8-dihydro-2'-deoxyguanosine and cyclobutane pyrimidine dimers lesions, respectively. We observed increased formation of hOGG1- and T4endoV-sensitive DNA lesions after light exposure (with or without RBAc). Furthermore, 18 h after irradiation, hOGG1-sensitive DNA lesions increased compared to that at the initial time point (0 h), which shows that a high melanin content contributes to post-irradiation formation of them, mainly via sustained oxidative stress, as confirmed by the measurement of ROS levels and activity of antioxidant enzymes. Contrastingly, the number of T4endoV-sensitive DNA lesions decreased over time (18 h). Our data indicate that in melanoma cells, a higher amount of melanin may affect DNA damage levels when subjected to RBAc-PDT.

Accumulation of nylon microplastics and polybrominated diphenyl ethers and effects on gut microbial community of Chironomus sancticaroli.

Microplastics (MP) are emerging contaminants with the capacity to bind and transport hydrophobic organic compounds of environmental concern, such as polybrominated diphenyl ethers (PBDEs). The aim of this study was to investigate the ingestion of nylon (polyamide) MP alone and when associated with PBDEs and their effects on Chironomus sancticaroli larvae survival and microbiome structure. Survival, PBDE uptake and microbial community composition were measured in fourth instar larvae exposed for 96 h to BDEs- 47, 99, 100 and 153 in the presence and absence of 1% w/w MP in sediment. Microbiome community structures were determined through high throughput sequencing of 16S small subunit ribosomal RNA gene (16S rRNA). Initial experiments showed that larvae ingested MP faster at 0.5% w/w MP, while depuration was more efficient at 1% w/w MP, although retention of MP was seen even after 168 h depuration. No mortality was observed as a result of PBDEs and MP exposure. MP had a negative effect on PBDE concentration within larvae (η2 = 0.94) and a negative effect on sediment concentrations (η2 = 0.48). In all samples, microbial communities were dominated by Alphaproteobacteria, Betaproteobacteria, Actinobacteria and Gammaproteobacteria. Bacterial alpha diversity was not significantly affected by PBDEs or MP exposure. However, the abundance of discrete bacterial taxa was more sensitive to MP (X2 = 45.81, p = 0.02), and PBDE exposure. Our results highlight that C. sancticaroli showed no acute response to MPs and PBDEs, but that MPs influenced bacterial microbiome structure even after only short-term acute exposure.

Natterin-like depletion by CRISPR/Cas9 impairs zebrafish (Danio rerio) embryonic development.

BACKGROUND: The Natterin protein family was first discovered in the venom of the medically significant fish Thalassophryne nattereri, and over the last decade natterin-like genes have been identified in various organisms, notably performing immune-related functions. Previous findings support natterin-like genes as effector defense molecules able to activate multiprotein complexes driving the host innate immune response, notably due to the pore-forming function of the aerolysin superfamily members. Herein, employing a combination of the CRISPR/Cas9 depletion system, phenotype-based screening, and morphometric methods, we evaluated the role of one family member, LOC795232, in the embryonic development of zebrafish since it might be implicated in multiple roles and characterization of the null mutant is central for analysis of gene activity. RESULTS: Multiple sequence alignment revealed that the candidate natterin-like has the highest similarity to zebrafish aep1, a putative and better characterized fish-specific defense molecule from the same family. Compared to other species, zebrafish have many natterin-like copies. Whole-mount in situ hybridization confirmed the knockout and mutant embryos exhibited epiboly delay, growth retardation, yolk sac and heart edema, absent or diminished swim bladder, spinal defects, small eyes and head, heart dysfunction, and behavioral impairment. As previously demonstrated, ribonucleoproteins composed of Cas9 and duplex guide RNAs are effective at inducing mutations in the F0 zebrafish. CONCLUSIONS: The considerably high natterin-like copies in zebrafish compared to other species might be due to the teleost-specific whole genome duplication and followed by subfunctionalization or neofunctionalization. In the present work, we described some of the natterin-like features in the zebrafish development and infer that natterin-like proteins potentially contribute to the embryonary development and immune response.

Zebrafish Beyond the Bench: The 'Plataforma Zebrafish Open Doors' Programme.

The Butantan Institute is a pioneering Brazilian health sciences institution, which also houses a large science park with museums that contribute to ongoing science education for schools and the wider community. In recent years, as part of Butantan Institute's Plataforma Zebrafish™, zebrafish embryos have been used for the dissemination of scientific knowledge during on-site events and as part of outreach campaigns to non-scientific audiences, mostly children. The aim of this work is mainly to demystify the activities of the scientific researcher, highlight the role of science in the furthering of knowledge, and increase public interest and confidence in science. In this article, the Institute's 'Plataforma Zebrafish Open Doors' programme is described, which offered guided tours of the laboratory facilities. The tours gave visitors the opportunity to observe zebrafish research and embryo development, and to use the knowledge gained from this experience as a framework for understanding fundamental ethical issues. During the 2-day event, around 800 visitors (most of them school-age children) attended. Together with the guided tours, our experience of outreach offered meaningful opportunities to bring children and members of the public closer to science and 'real-life' scientists, hopefully inspiring and encouraging the next generation of scientists. It also gave the scientists an opportunity to engage more closely with wider society. We believe that these activities also substantially contribute to the wider dissemination of relevant experimental results that have been obtained with public funding and that impact society in general.

Where the Aryl Hydrocarbon Receptor Meets the microRNAs: Literature Review of the Last 10 Years.

The aryl hydrocarbon receptor (AhR) is an environmentally responsive ligand-activated transcription factor, identified in the '70s for its toxic responses to halogenated polycyclic aromatic hydrocarbons, such as dioxin. Recently, AhR has been recognized as engaged in multiple physiological processes in health and diseases, particularly in the immune system, inflammatory response, tumorigenesis, and cellular differentiation by epigenetic mechanisms involving miRNAs. However, there is still scarce information about AhR-dependent miRNA regulation and miRNA-mediated epigenetic control in pathologies and therapies. In this review, we explore the mutual regulation of AhR and miRNA over the last decade of studies since many miRNAs have dioxin response elements (DRE) in their 3' UTR, as well as AhR might contain binding sites of miRNAs. TCDD is the most used ligand to investigate the impact of AhR activation, and the immune system is one of the most sensitive of its targets. An association between TCDD-activated AhR and epigenetic mechanisms like post-transcriptional regulation by miRNAs, DNA methylation, or histone modification has already been confirmed. Besides, several studies have shown that AhR-induced miR-212/132 cluster suppresses cancers, attenuates autoimmune diseases, and has an anti-inflammatory role in different immune responses by regulating cytokine levels and immune cells. Together the ever-expanding new AhR roles and the miRNA therapeutics are a prominent segment among biopharmaceuticals. Additionally, AhR-activated miRNAs can serve as valuable biomarkers of diseases, notably cancer progression or suppression and chemical exposure. Once AhR-dependent gene expression may hinge on the ligand, cell type, and context singularity, the reviewed outcomes might help contextualize state of the art and support new trends and emerging opportunities in the field.

The Natterin Proteins Diversity: A Review on Phylogeny, Structure, and Immune Function.

Since the first record of the five founder members of the group of Natterin proteins in the venom of the medically significant fish Thalassophryne nattereri, new sequences have been identified in other species. In this work, we performed a detailed screening using available genome databases across a wide range of species to identify sequence members of the Natterin group, sequence similarities, conserved domains, and evolutionary relationships. The high-throughput tools have enabled us to dramatically expand the number of members within this group of proteins, which has a remote origin (around 400 million years ago) and is spread across Eukarya organisms, even in plants and primitive Agnathans jawless fish. Overall, the survey resulted in 331 species presenting Natterin-like proteins, mainly fish, and 859 putative genes. Besides fish, the groups with more species included in our analysis were insects and birds. The number and variety of annotations increased the knowledge of the obtained sequences in detail, such as the conserved motif AGIP in the pore-forming loop involved in the transmembrane barrel insertion, allowing us to classify them as important constituents of the innate immune defense system as effector molecules activating immune cells by interacting with conserved intracellular signaling mechanisms in the hosts.

Molecular Characterization and Functional Analysis of the Nattectin-like Toxin from the Venomous Fish Thalassophryne maculosa.

TmC4-47.2 is a toxin with myotoxic activity found in the venom of Thalassophryne maculosa, a venomous fish commonly found in Latin America whose envenomation produces an injury characterized by delayed neutrophil migration, production of major pro-inflammatory cytokines, and necrosis at the wound site, as well as a specific systemic immune response. However, there are few studies on the protein structure and functions associated with it. Here, the toxin was identified from the crude venom by chromatography and protein purification systems. TmC4-47.2 shows high homology with the Nattectin from Thalassophryne nattereri venom, with 6 cysteines and QPD domain for binding to galactose. We confirm its hemagglutinating and microbicide abilities independent of carbohydrate binding, supporting its classification as a nattectin-like lectin. After performing the characterization of TmC4-47.2, we verified its ability to induce an increase in the rolling and adherence of leukocytes in cremaster post-capillary venules dependent on the α5ß1 integrin. Finally, we could observe the inflammatory activity of TmC4-47.2 through the production of IL-6 and eotaxin in the peritoneal cavity with sustained recruitment of eosinophils and neutrophils up to 24 h. Together, our study characterized a nattectin-like protein from T. maculosa, pointing to its role as a molecule involved in the carbohydrate-independent agglutination response and modulation of eosinophilic and neutrophilic inflammation.

The Toxic Effects of Glyphosate, Chlorpyrifos, Abamectin, and 2,4-D on Animal Models: A Systematic Review of Brazilian Studies.

Brazil is a global agricultural commodity producer and the largest consumer of pesticides. Pesticide use in Brazil comprised 549 280 tons in 2018. In the country, soybean, corn, and sugar cane are extensively produced, which are the most pesticides demanding crops. In the last years, the records of new pesticides were the highest in the historical series. They can persist in soil or water, accumulate in organisms, and contaminate workers and the general population through the air, water, or food. This review aimed to gather toxicological data obtained by animal models exposed to 4 pesticides: glyphosate, chlorpyrifos, abamectin, and 2,4-D. An additional goal was to compose an overview of how this subject has been approached, surveying which research groups are working on this field, where they are located, and relations with pesticides used in those regions. We collected the papers from the platforms PubMed, Scopus, Scielo, and Web of Science, performed in Brazil from 2014 to 2019. After two-step blind selection using the software Rayyan QCRI by different authors, 67 studies were selected to extract data. We observed that research is more concentrated in the South region, followed by the Southeast and Midwest, with 43%, 32%, and 23% of the studies, respectively. The prevalent institutions are from the states of Rio Grande do Sul, São Paulo, and Goiás. The effects on a variety of biomarkers help predict the potential risks to humans and nontarget organisms. The prevalent animal model was fish (36%). Overall, the main toxic effects evaluated were mortality, abnormalities in the blood cells, developmental abnormalities, and behavior alterations. Integr Environ Assess Manag 2021;17:507-520. © 2020 SETAC.

Early preclinical screening using zebrafish (Danio rerio) reveals the safety of the candidate anti-inflammatory therapeutic agent TnP.

The patented anti-inflammatory peptide TnP had its effectiveness recently confirmed in vivo in a murine model of multiple sclerosis and asthma. In this work, the safety of the TnP was evaluated in investigative toxicology tests using zebrafish (Danio rerio) as a model. We conducted the OECD #236 test to investigate effects of the TnP on the survival, hatching performance, and morphological formation of zebrafish embryos. After determining these endpoints, morphometric analysis termination of locomotion eartbeat rate in zebrafish larvae were evaluated to identify adverse effects such as neurotoxicity and cardiotoxicity. The results highlight a wide therapeutic index for TnP with non-lethal and safe doses rom 1 nM to 10 µM, without causing neurotoxicity or cardiotoxic effect. The low frequencyf abnormalities by TnP was associated with high safety of the molecule and the developing embryo's ability to process and eliminate it. TnP crossed the blood-brain barrier without disturbing the normal architecture of forebrain, midbrain and hindbrain. Our data reinforce the importance of zebrafish as an accurate investigative toxicology model to assess acute toxicity as well as cardiotoxicity and neurotoxicity of molecules in the preclinical phase of development.

A test battery for assessing the ecotoxic effects of textile dyes.

The textile dyeing industry is one of the main sectors contributing to environmental pollution, due to the generation of large amounts of wastewater loaded with dyes (ca. 2-50% of the initial amount of dyes used in the dye baths is lost), causing severe impacts on human health and the environment. In this context, an ecotoxicity testing battery was used to assess the acute toxicity and genotoxicity of the textile dyes Direct Black 38 (DB38; azo dye) and Reactive Blue 15 (RB15; copper phthalocyanine dye) on different trophic levels. Thus these dyes were tested using the following assays: Filter paper contact test with earthworms (Eisenia foetida); seed germination and root elongation toxicity test (Cucumis sativus, Lactuca sativa and Lycopersicon esculentum); acute immobilization test (Daphnia magna and Artemia salina); and the Comet assay with the rainbow trout gonad-2 cell fish line (RTG-2) and D. magna. Neither phytotoxicity nor significant effects on the survival of E. foetida were observed after exposure to DB38 and RB15. Both dyes were classified as relatively non-toxic to D. magna (LC50 > 100 mg/L), but DB38 was moderately toxic to A. salina with a LC50 of 20.7 mg/L. DB38 and RB15 induced significant effects on the DNA of D. magna but only DB38 caused direct (alkaline comet assay) and oxidative (hOGG1-modified alkaline comet assay) damage to RTG-2 cells in hormetic responses. Therefore, the present results emphasize that a test battery approach of bioassays representing multiple trophic levels is fundamental in predicting the toxicity of textile dyes, aside from providing the information required to define their safe levels for living organisms in the environment.

Effects of low concentrations of ibuprofen on freshwater fish Rhamdia quelen.

Ibuprofen is a pharmaceutical drug widely used by the global population and it has been found in aquatic ecosystems in several countries. This study evaluated the effects of ibuprofen in environmental concentrations (0, 0.1, 1 and 10 µg/L) on the freshwaterspecies Rhamdia quelen exposed for 14 days. In the posterior kidney, ibuprofen increased glutathione-S-transferase activity in all groups exposed. Furthermore, increased glutathione peroxidase activity and the levels of reduced glutathione in the group exposed to 10 µg/L. Ibuprofen decreased the carbonic anhydrase activity in the posterior kidney in all exposed groups, and increased the activity in the gills in group exposed to 0.1 µg/L. The levels of plasma magnesium increased in groups exposed to 0.1 and 1 µg/L. In the blood, ibuprofen decreased the white blood cell count in groups exposed to 0.1 e 1.0 µg/L. Therefore, these results indicated that ibuprofen caused nephrotoxicity and demonstrated immunosuppressive effect in Rhamdia quelen.

Antibody levels to hantavirus in inhabitants of western Santa Catarina State, Brazil.

Hantavirus cardiopulmonary syndrome (HCPS) is an infectious disease caused by hantaviruses of the family Bunyaviridae, and is transmitted by aerosols of excreta of infected rodents. The aim of the present study was to determine antibody levels to hantavirus in the population that lives at frontier of Brazil and Argentina. Participated of the study 405 individuals living in the municipalities of Bandeirante, Santa Helena, Princesa and Tunapolis, state of Santa Catarina, Brazil. IgG antibodies to hantavirus were analyzed in sera by an ELISA that uses a recombinant N protein of Araraquara hantavirus as antigen. The results were also confirmed by immunofluorescent test. Eight individuals showed antibodies to hantavirus (1.97% positivity), with serum titers ranging from 100 to 800. Six seropositives were males, older than 30 years and farmers. Our results reinforce previous data on hantavirus circulation and human infections in the southern border of Brazil with Argentina.

Antibody levels to hantavirus in inhabitants of western Santa Catarina State, Brazil / Níveis de anticorpos para hantavírus em habitantes da região Oeste de Santa Catarina, Brasil

Hantavirus cardiopulmonary syndrome (HCPS) is an infectious disease caused by hantaviruses of the family Bunyaviridae, and is transmitted by aerosols of excreta of infected rodents. The aim of the present study was to determine antibody levels to hantavirus in the population that lives at frontier of Brazil and Argentina. Participated of the study 405 individuals living in the municipalities of Bandeirante, Santa Helena, Princesa and Tunapolis, state of Santa Catarina, Brazil. IgG antibodies to hantavirus were analyzed in sera by an ELISA that uses a recombinant N protein of Araraquara hantavirus as antigen. The results were also confirmed by immunofluorescent test. Eight individuals showed antibodies to hantavirus (1.97% positivity), with serum titers ranging from 100 to 800. Six seropositives were males, older than 30 years and farmers. Our results reinforce previous data on hantavirus circulation and human infections in the southern border of Brazil with Argentina.

Síndrome Cardiopulmonar por Hantavírus (HCPS) é uma doença emergente, causada pelo gênero hantavírus membro da família Bunyaviridae, e são transmitidos aos humanos por aerossol de roedores infectados. O objetivo principal deste estudo foi determinar os níveis de anticorpos para hantavírus em uma população de residentes na fronteira do Brasil com a Argentina. Participaram deste estudo 405 indivíduos que moravam nos municípios de Bandeirante, Santa Helena, Princesa e Tunapólis, no estado de Santa Catarina, Brasil. Os anticorpos IgG para hantavírus foram analisados no soro por um ELISA que usa a nucleoproteína recombinante do vírus Araraquara como antígeno, posteriormente confirmados por imunofluorescência. Oito indivíduos apresentavam anticorpos para hantavírus (1.97% positivo), com titulo entre 100 a 800. Seis soropositivos foram homens, com idade superior a 30 anos e agricultores. Nossos resultados reforçam a circulação do hantavírus e infecção humana na fronteira do Brasil com a Argentina.