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To identify activation pathways and effector mechanisms of innate immunity in fish has become relevant for the sanitary management of intensive fish farming. However, little is known about the blocking of cysteinyl leukotrienes receptors (CysLTRs) and their effects in teleost fish. Our study evaluated the anti-inflammatory effect of 250 and 500 μg zafirlukast (antagonist of CysLTRs)/kg b.w., administered orally in the diet, during acute inflammatory reaction induced by Aeromonas hydrophila bacterins in Oreochromis niloticus. 80 tilapia were distributed in 10 aquariums (100L of water each, n = 8) to constitute three treatments: Control (inoculated with A. hydrophila bacterin and untreated); Treated with 250 μg or 500 μg of zafirlukast/kg b.w. and inoculated. To be evaluated in three periods: 6, 24 and 48 h post-inoculation (HPI), totaling nine aquariums. A tenth group was sampled without any stimulus to constitute reference values (Physiological standards). Tilapia treated with zafirlukast demonstrated dose-response effect in the decrease of accumulated inflammatory cells, strongly influenced by granulocytes and macrophages. Zafirlukast treated-tilapia showed decrease in blood leukocyte counts (mainly neutrophils, and monocytes) and reactive oxygen species production. Treatment with zafirlukast resulted in down-regulation of ceruloplasmin, complement 3, alpha2-macroglobulin, transferrin and apolipoprotein A1, as well as up-regulation of haptoglobin. Our study provided convincing results in the pathophysiology of tilapia inflammatory reaction, considering that treatment with zafirlukast, antagonist of cysteinyl leukotriene receptors, resulted in a dose-response effect by suppressing the dynamics between leukocytes in the bloodstream and cell accumulation in the inflamed focus, as well as modulated the leukocyte oxidative burst and the acute phase protein response.

Limitations of the recognition elements in terms of synthesis, cost, availability, and stability have impaired the translation of biosensors into practical use. Inspired by nature to mimic the molecular recognition of the anti-SARS-CoV-2 S protein antibody (Ab

Bacillus spp. supplementation as probiotics in cultured fish diets has a long history of safe and effective use. Specifically, B. velezensis show great promise in fine-tuning the European sea bass disease resistance against the pathogenicity caused by several members of the Vibrio family. However, the immunomodulatory mechanisms behind this response remain poorly understood. Here, to examine the inherent immune variations in sea bass, two equal groups were fed for 30 days with a steady diet, with one treatment supplemented with B. velezensis. The serum bactericidal capacity against live cells of Vibrio anguillarum strain 507 and the nitric oxide and lysozyme lytic activities were assayed. At the cellular level, the phagocytic response of peripheral blood leukocytes against inactivated Candida albicans was determined. Moreover, head-kidney (HK) total leukocytes were isolated from previously in vivo treated fish with LPS of V. anguillarum strain 507. Mechanistically, the expression of some essential proinflammatory genes (interleukin-1 (il1b), tumor necrosis factor-alpha (tnfa), and cyclooxygenase 2 (cox2) and the sea bass specific antimicrobial peptide (AMP) dicentracin (dic) expressions were assessed. Surprisingly, the probiotic supplementation significantly increased all humoral lytic and cellular activities assayed in the treated sea bass. In addition, time-dependent differences were observed between the control and probiotic treated groups for all the HK genes markers subjected to the sublethal LPS dose. Although the il1b was the fastest responding gene to a significant level at 48 h post-injection (hpi), all the other genes followed 72 h in the probiotic supplemented group. Finally, an in vivo bacteria challenge against live V. anguillarum was conducted. The probiotic fed fish observed a significantly higher survival. Overall, our results provide clear vertical evidence on the beneficial immune effects of B. velezensis and unveil some fundamental immune mechanisms behind its application as a probiotic agent in intensively cultured European sea bass.

Despite all efforts to combat the pandemic of COVID-19, we are still living with high numbers of infected persons, an overburdened health care system, and the lack of an effective and definitive treatment. Understanding the pathophysiology of the disease is crucial for the development of new technologies and therapies for the best clinical management of patients. Since the manipulation of the whole virus requires a structure with an adequate level of biosafety, the development of alternative technologies, such as the synthesis of peptides from viral proteins, is a possible solution to circumvent this problem. In addition, the use and validation of animal models is of extreme importance to screen new drugs and to compress the organism's response to the disease. Peptides derived from recombinant S protein from SARS-CoV-2 were synthesized and validated by in silico, in vitro and in vivo methodologies. Macrophages and neutrophils were challenged with the peptides and the production of inflammatory mediators and activation profile were evaluated. These peptides were also inoculated into the swim bladder of transgenic zebrafish larvae at 6 days post fertilization to mimic the inflammatory process triggered by the virus, which was evaluated by confocal microscopy. In addition, toxicity and oxidative stress assays were also developed. In silico and molecular dynamics assays revealed that the peptides bind to the ACE2 receptor stably and interact with receptors and adhesion molecules, such as MHC and TCR, from humans and zebrafish. Macrophages stimulated with one of the peptides showed increased production of NO, TNF-α and CXCL2. Inoculation of the peptides in zebrafish larvae triggered an inflammatory process marked by macrophage recruitment and increased mortality, as well as histopathological changes, similarly to what is observed in individuals with COVID-19. The use of peptides is a valuable alternative for the study of host immune response in the context of COVID-19. The use of zebrafish as an animal model also proved to be appropriate and effective in evaluating the inflammatory process, comparable to humans.

This work presents the first study showing how photobiomodulation (PBM) significantly increases cellular and tissue repair and elucidating the role of PBM with low-level laser as a possible new therapy in pathologies in COVID-19-associated cytokine storm syndrome from a zebrafish model. Our results demonstrate new strategies for treating SARS-COV-2 using PBM to modulate the expression of the genes and metabolites involved in inflammatory processes. These metabolic alterations show that the r-Spike led to disturbance in the energetic and inflammatory system, corroborating with the severe clinical conditions of human patients. Furthermore, PBM decreased the gene expression levels of pro-inflammatory cytokines such as il1b, il6, tnfa, and nfkbiab, and of factors involved in oxidative stress (romo1) and energy metabolism (slc2a1a, coa1), in various tissues, promoting an anti-inflammatory response. In summary, our study suggests that PBM may have a positive role in treating cytokine storm syndrome associated with COVID-19. PBM can significantly regulate the inflammatory response promoting cellular and tissue repair of injured tissues. This work suggests that PBM may have a positive role in treating COVID-19-associated cytokine storm syndrome. Nevertheless, the need for more clinical trials remains, and there is a significant gap to overcome before clinical trials.

Due to their general cytotoxic effects, anticancer drugs pose a great risk to aquatic species, yet they have been among the least studied groups of drugs regarding their environmental impact. The present study aimed to identify the effects of the antileukemia drug cytarabine, also known as cytosine arabinoside (ara-C), on the development and neurobehavior of zebrafish larvae. Zebrafish eggs were exposed to cytarabine to assess survival, embryonic malformations, locomotor activity, DNA damage, and biochemical alterations. No mortality, teratogenicity, or genotoxicity was detected in zebrafish larvae up to 100 mg L-1. However, cytarabine decreased the total distance traveled by zebrafish under dark conditions, suggesting depression-like behavior in treated larvae. Furthermore, it was demonstrated that cytarabine exposure increased lipid peroxidation (LPO) and acetylcholinesterase (AChE) activity, while it inhibited catalase (CAT) activity. Multivariate analysis suggested that both AChE and LPO correlated to behavioral changes, while molecular docking and dynamics simulations suggested a direct binding and stability of cytarabine to AChE. Further analyses of the effects of this anticancer compound in the cholinergic transmission are in progress to allow a better understanding of its neurotoxicity.

Blood tissue has been used to assess animal health and the environment in which they live. This tissue is easily acquired and has the ability to respond to various adverse conditions. Several techniques have been employed in the detection of xenobiotic-induced cell damage in blood cells. In general, traditionally used technologies, such as cellular analysis in blood smears, are time-consuming and require great analytical capacity. The present study proposes flow cytometry as a method to detect changes in blood cell populations. Tilapia (Oreochromis niloticus) was selected as a model for plotting the profile of fish blood cell populations after exposure to xenobiotics without euthanizing animals or using cell markers. Populations of erythrocytes and lymphocytes were detected only by combining the techniques of FACSAria cell sorting and light microscopy. Systemic deleterious effects were found through blood analysis, such as an increased lymphocyte-rich population at 48 h of exposure followed by a subsequent decrease. Moreover, the time-dependent expression of Nrf2 suggests its participation in increased membrane disruption, indicating it has a central role in erythrocyte lifespan. The present results shed light on the viability of using flow cytometry for blood analysis of living fish.

Made available in DSpace on 2022-04-29T08:46:36Z (GMT). No. of bitstreams: 0 Previous issue date: 2022-04-01 There have been significant impacts of the current COVID-19 pandemic on society including high health and economic costs. However, little is known about the potential ecological risks of this virus despite its presence in freshwater systems. In this study, we aimed to evaluate the exposure of Poecilia reticulata juveniles to two peptides derived from Spike protein of SARS-CoV-2, which was synthesized in the laboratory (named PSPD-2002 and PSPD-2003). For this, the animals were exposed for 35 days to the peptides at a concentration of 40 µg/L and different toxicity biomarkers were assessed. Our data indicated that the peptides were able to induce anxiety-like behavior in the open field test and increased acetylcholinesterase (AChE) activity. The biometric evaluation also revealed that the animals exposed to the peptides displayed alterations in the pattern of growth/development. Furthermore, the increased activity of superoxide dismutase (SOD) and catalase (CAT) enzymes were accompanied by increased levels of malondialdehyde (MDA), reactive oxygen species (ROS) and hydrogen peroxide (H2O2), which suggests a redox imbalance induced by SARS-CoV-2 spike protein peptides. Moreover, molecular docking analysis suggested a strong interaction of the peptides with the enzymes AChE, SOD and CAT, allowing us to infer that the observed effects are related to the direct action of the peptides on the functionality of these enzymes. Consequently, our study provided evidence that the presence of SARS-CoV-2 viral particles in the freshwater ecosystems offer a health risk to fish and other aquatic organisms. Biological Research Laboratory Post-Graduation Program in Conservation of Cerrado Natural Resources Goiano Federal Institute, Urutaí Campus, Rodovia Geraldo Silva Nascimento, 2,5km, Zona Rural CEP, GO Post-Graduation Program in Biotechnology and Biodiversity Goiano Federal Institution and Federal University of Goiás, GO Post-Graduation Program in Ecology and Conservation of Natural Resources Federal University of Uberlândia, MG Plant Protection Department Faculty of Agriculture Assiut University Post-Graduation Programa in Environmental Sciences Federal University of Goiás, GO Department of Pharmacology Institute of Biomedical Sciences University of Sao Paulo, SP Drug Research and Development Center Federal University of Ceará, CE Department of Physiology and Pharmacology School of Medicine Federal University of Ceará, CE Instituto de Química Universidade Estadual Paulista, SP Departamento de Imunologia Instituto de Ciências Biomédicas Universidade de São Paulo, SP Instituto de Química Universidade Estadual Paulista, SP

Despite advances in research on the vaccine and therapeutic strategies of COVID-19, little attention has been paid to the possible (eco)toxicological impacts of the dispersion of SARS-CoV-2 particles in natural environments. Thus, in this study, we aimed to evaluate the behavioral and biochemical consequences of the short exposure of outbred and inbred mice (male Swiss and C57Bl/6 J mice, respectively) to PSPD-2002 (peptide fragments of the Spike protein of SARS-CoV-2) synthesized in the laboratory. Our data demonstrated that after 24 h of intraperitoneal administration of PSPD-2002 (at 580 μg/kg) the animals did not present alterations in their locomotor, anxiolytic-like, or anxiety-like behavior (in the open field test), nor antidepressant-like or depressive behavior in the forced swimming test. However, the C57Bl/6 J mice exposed to PSPD-2002 showed memory deficit in the novel object recognition task, which was associated with higher production of thiobarbituric acid reactive substances, as well as the increased suppression of acetylcholinesterase brain activity, compared to Swiss mice also exposed to peptide fragments. In Swiss mice the reduction in the activity of superoxide dismutase and catalase in the brain was not associated with increased oxidative stress biomarkers (hydrogen peroxide), suggesting that other antioxidant mechanisms may have been activated by exposure to PSPD-2002 to maintain the animals' brain redox homeostasis. Finally, the results of all biomarkers evaluated were applied into the "Integrated Biomarker Response Index" (IBRv2) and the principal component analysis (PCA), and greater sensitivity of C57Bl/6 J mice to PSPD-2002 was revealed. Therefore, our study provides pioneering evidence of mammalian exposure-induced toxicity (non-target SARS-CoV-2 infection) to PSPD-2002, as well as "sheds light" on the influence of genetic profile on susceptibility/resistance to the effects of viral peptide fragments., The authors are grateful to the Goiano Federal Institute and the National Council for Scientific and Technological Development (CNPq/Brazil) for the financial support needed to conduct this research (Proc. No. 23219.000137.2022-28 and 403065/2021-6, respectively). Malafaia G. holds a productivity scholarship from CNPq (Proc. No. 307743/2018-7).

Made available in DSpace on 2021-06-25T15:38:43Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-09-16 Fundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Artemisinin (ART) was initially described for the control of inflammation and pain. However, the mechanisms involved with its antinociceptive effect are still poorly understood. Thus, this present study aimed to investigate the effect of ART in both free and nanocapsulated form on postoperative pain, as well as the participation of the spinal Toll-like receptor 4 (TLR4) in this process. Postoperative pain was induced using the skin/muscle incision retraction (SMIR) model in male Swiss mice. After 3 and 28 days of SMIR, the animals received an intrathecal injection of free or nanocapsulated ART, and the nociceptive threshold was evaluated by von Frey filament test. To evaluate the involvement of the microglia, astrocytes, and TLR4, minocycline (a microglia inhibitor), fluorocitrate (an astrocyte inhibitor), andLipopolysaccharide Rhodobacter sphaeroides(LPS-RS), a TLR4 antagonist, were intrathecally injected on the third day of SMIR. The levels of spinal TLR4 protein and proinflammatory cytokines tumor necrosis factor-alpha (TNF-alpha), and interleukin-1-beta (IL-1 beta) were quantified by western blot and enzyme-linked immunosorbent assay, respectively. The results showed that free ART reduced postoperative pain (P < 0.001,F-5,F-30 = 7.49, 16.66% for 1000 ng dose; andP < 0.01,F-5,F-30 = 7.49, 14.58% for 500 ng dose) on the 3rd day of SMIR; while the ART nanocapsule had this effect on both the third (P < 0.001;F-5,F-30 = 4.94; 43.75, 39.58 and 72.91% for the 250, 500 and 1000 ng doses, respectively) and 28th (P < 0.05;F-5,F-30 = 7.71; 29.16 and 33.33% for the 500 and 1000 ng doses, respectively) day. The ART nanocapsule had a more potent and longer antinociceptive effect than free ART or morphine. Postoperative pain was also reduced by minocycline and LPS-RS. The ART nanocapsule also reduced the increased levels of TLR4, TNF-alpha, and IL-1 beta induced by SMIR. These data suggest that the ART nanocapsule has a potent analgesic effect on postoperative pain at the spinal level, and this response involves the inhibition of TLR4 and the proinflammatory cytokines TNF-alpha and IL-1 beta. Univ Fed Alfenas, Fac Motr Sci, Sci Motr Inst, Jovino Fernandes Sales Ave 2600, BR-37133840 Alfenas, Brazil Univ Sao Paulo, Dept Pharmacol, Sao Paulo, Brazil Univ Estadual Campinas, Fac Pharmaceut Sci, Campinas, Brazil Sao Paulo State Univ, Inst Sci & Technol, Sorocaba, Brazil Univ Sao Paulo, Ribeirao Preto Med Sch, Dept Pharmacol, Ribeirao Preto, Brazil Sao Paulo State Univ, Inst Sci & Technol, Sorocaba, Brazil CAPES: 001 FAPESP: 2014/16008-3

Establishing new animal models for the study of inflammation is very important in the process of discovering new drugs, since the inflammatory event is the basis of many pathological processes. Whereas rodent models have been the primary focus of inflammation research, we defend the zebrafish (Danio rerio) test as a feasible alternative for preclinical studies. Moreover, despite all the technological development already achieved by humanity, nature can still be considered a relevant source of new medicines. In this context, the aim of this work was to evaluate the anti-inflammatory effect of a substance isolated from the medicinal plant Annona crassilfora Mart, the peltatoside, in an inflammatory model of zebrafish. It was determined: (i) total leukocyte count in the coelomate exudate; (ii) N-acetyl-β-d-glucuronidase (NAG); (iii) myeloperoxidase (MPO); (iv) and the histology of liver, intestine and mesentery. Peltotoside (25, 50 and 100 μg) and dexamethasone (25 μg) were administered intracelomatically (i.c.) 30 min before carrageenan (i.c.). Pretreatment with peltatoside at three doses significantly inhibited leukocyte recruitment in the coelomic cavity, and inhibited NAG and MPO activity against the action of Cg, in a similar manner as dexamethasone. However, some microlesions in the evaluated organs were detected. The dose of 25 μg showed an anti-inflammatory effect with lower undesirable effects in the tissues. Our results suggest that the zebrafish test was satisfactory in performing our analyzes and that the peltotoside has a modulatory action in reducing leukocyte migration.

Made available in DSpace on 2022-05-01T13:41:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2022-01-01 BACKGROUND: Astaxanthin, classified as a xanthophyll, has antioxidant properties about 500 times greater than α-tocopherols and ten times greater than β-carotenes. Based on the antioxidant activity of this carotenoid, this study aimed to evaluate the shelf-life of tilapia fillets (Oreochromis niloticus) fed with astaxanthin, by determining the microbiological quality (colimetry, counts of mesophilic and psychrotrophic microorganisms), physicochemical analyses (colorimetry, pH, thiobarbituric acid reactive substances (TBARS)) and sensory analysis. RESULTS: Tilapia supplemented with astaxanthin presented a reduction in the counts of microorganisms (mesophiles and psychrotrophics) and lower lipid oxidation index (TBARS), when compared to fillets of control fish. Colorimetric changes of fillet degradation were observed, associated with increased pH during storage, as well as loss of brightness and texture in addition to worsening of appearance and odor. These deteriorating changes were minimized using astaxanthin. CONCLUSION: Our results demonstrate the beneficial performance of astaxanthin in the shelf-life of tilapia fillets stored under refrigeration. Therefore, dietary supplementation with astaxanthin (100 and 200 mg kg−1 of feed) improves the microbiological and physicochemical quality of tilapia fillets during 50 days of shelf-life. © 2022 Society of Chemical Industry. Department of Preventive Veterinary Medicine Sao Paulo State University (Unesp) Department of Pharmacology Institute of Biomedical Science University of São Paulo-ICB/USP Immunochemistry Laboratory Butantan Institute Department of Postgraduate in Health Sciences-PROCISA Federal University of Roraima (UFRR) Laboratory of Animal Pharmacology and Toxicology Brazil University (UB) Department of Preventive Veterinary Medicine Sao Paulo State University (Unesp)

Atrazine (ATZ) is a herbicide that is frequently present in surface waters and may result in damage to the health of various organisms, including humans. However, most scientific literature reports injuries caused by ATZ at high concentrations, which are not found in the environment. Therefore, the scope of this study was to investigate the impacts of realistic concentrations of ATZ found in surface waters (1, 2, 5, 10, 15 and 20 μg/L) using the bioindicators Allium cepa, Daphnia magna and zebrafish (Danio rerio). ATZ elicited a genotoxic effect in A. cepa, manifested by the induction of chromosomal aberrations, and a mutagenic effect with increased incidence of micronuclei formation, promotion of cell death and reduction in nuclear size revealed by flow cytometry analysis. D. magna exposed to 10, 15 and 20 μg/L of ATZ showed significant reduction in body size after 21 days, delayed first-brood release, decreased egg production and total offspring, as well as swimming behavioral changes. ATZ exposure promoted physiological and developmental alterations in zebrafish embryos, including an increased spontaneous movement rate, which led to premature hatching at all concentrations investigated. Increase in total body length, decrease of the yolk sac area, pericardial edema and higher heart rate were also detected in ATZ-treated zebrafish. In summary, environmentally relevant concentrations of ATZ can induce substantial alterations in the three bioindicators investigated. This study evidences the deleterious effects of ATZ on three aquatic bioindicators employing established and current techniques, and may contribute to elucidate the risks caused by this widely used herbicide even at low concentrations and short-to-medium-term exposure.

Despite the significant increase in the generation of SARS-CoV-2 contaminated domestic and hospital wastewater, little is known about the ecotoxicological effects of the virus or its structural components in freshwater vertebrates. In this context, this study evaluated the deleterious effects caused by SARS-CoV-2 Spike protein on the health of Danio rerio, zebrafish. We demonstrated, for the first time, that zebrafish injected with fragment 16 to 165 (rSpike), which corresponds to the N-terminal portion of the protein, presented mortalities and adverse effects on liver, kidney, ovary and brain tissues. The conserved genetic homology between zebrafish and humans might be one of the reasons for the intense toxic effects followed inflammatory reaction from the immune system of zebrafish to rSpike which provoked damage to organs in a similar pattern as happen in severe cases of COVID-19 in humans, and, resulted in 78,6% of survival rate in female adults during the first seven days. The application of spike protein in zebrafish was highly toxic that is suitable for future studies to gather valuable information about ecotoxicological impacts, as well as vaccine responses and therapeutic approaches in human medicine. Therefore, besides representing an important tool to assess the harmful effects of SARS-CoV-2 in the aquatic environment, we present the zebrafish as an animal model for translational COVID-19 research., Graphical abstract Unlabelled Image

Advances in vaccine development depend on animal models to test innovative therapies. Recent studies have reported the successful introduction of teleost fish as a new vertebrate model in scientific research, with emphasis on the species Danio rerio (zebrafish). This chapter aims to give an overview of important aspects related to the immune system of fish, as well as the current progress of the successful use of these animals in studies for the development of vaccines, assisting in the determination of efficacy and clinical safety. Among the advantages of using fish for the development of vaccines and immunomodulatory drugs, it is worth highlighting the reproductive capacity of these animals resulting in a high number of individuals belonging to the same spawning, transparent embryos, low cost of breeding and high genetic similarity that favor translational responses to vertebrate organisms like humans.

The SARS-CoV-2 pandemic have been affecting millions of people worldwide, since the beginning of 2020. COVID-19 can cause a wide range of clinical symptoms, which varies from asymptomatic presentation to severe respiratory insufficiency, exacerbation of immune response, disseminated microthrombosis and multiple organ failure, which may lead to dead. Due to the rapid spread of SARS-CoV-2, the development of vaccines to minimize COVID-19 severity in the world population is imperious. One of the employed techniques to produce vaccines against emerging viruses is the synthesis of recombinant proteins, which can be used as immunizing agents. Based on the exposed, the aim of the present study was to verify the systemic and immunological effects of IM administration of recombinant Nucleocapsid protein (NP), derived from SARS-CoV-2 and produced by this research group, in 2 different strains of rats (Rattus norvegicus); Wistar and Lewis. For this purpose, experimental animals received 4 injections of NP, once a week, and were submitted to biochemical and histological analysis. Our results showed that NP inoculations were safe for the animals, which presented no clinical symptoms of worrying side effects, nor laboratorial alterations in the main biochemical and histological parameters, suggesting the absence of toxicity induced by NP. Moreover, NP injections successfully triggered the production of specific anti-SARS-CoV-2 IgG antibodies by both Wistar and Lewis rats, showing the sensitization to have been well sufficient for the immunization of these strains of rats. Additionally, we observed the local lung activation of the Bronchus-Associated Lymphoid Tissue (BALT) of rats in the NP groups, suggesting that NP elicits specific lung immune response. Although pre-clinical and clinical studies are still required, our data support the recombinant NP produced by this research group as a potential immunizing agent for massive vaccination, and may represent advantages upon other recombinant proteins, since it seems to induce specific pulmonary protection.

Made available in DSpace on 2022-04-28T19:45:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-12-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) This study aims to demonstrate the applicability and importance of zebrafish (Danio rerio) model to study acute and chronic inflammatory responses induced by different stimuli: carrageenan phlogogen (nonimmune); acute infection by bacteria (immune); foreign body reaction (chronic inflammation by round glass coverslip implantation); reaction induced by xenotransplantation. In addition to the advantages of presenting low breeding cost, high prolificity, transparent embryos, high number of individuals belonging to the same spawning and high genetic similarity that favor translational responses to vertebrate organisms like humans, zebrafish proved to be an excellent tool, allowing the evaluation of edema formation, accumulation of inflammatory cells in the exudate, mediators, signaling pathways, gene expression and production of specific proteins. Our studies demonstrated the versatility of fish models to investigate the inflammatory response and its pathophysiology, essential for the successful development of studies to discover innovative pharmacological strategies. Laboratory of Animal Pharmacology and Toxicology Brazil University (UB) Department of Preventive Veterinary Medicine São Paulo State University (UNESP) Department of Morphology Federal University of Minas Gerais (UFMG) Department of Physiology and Pharmacology Federal University of Minas Gerais (UFMG) Department of Biochemistry and Immunology Federal University of Minas Gerais (UFMG) Department of zootechnics at the Veterinary School Federal University of Minas Gerais (UFMG) Postgraduate Program in Health Sciences - PROCISA Federal University of Roraima Immunochemistry Laboratory Butantan Institute Department of Clinical and Toxicological Analyses Federal University of Minas Gerais (UFMG) Department of Pharmacology University of São Paulo (ICB-USP) Department of Preventive Veterinary Medicine São Paulo State University (UNESP) FAPESP: 2013/25971-9 FAPESP: 2018/07098-0 FAPESP: 2019/19939-1 CNPq: 301473 / 2016-1 CNPq: 307526/2018-6 CNPq: 477816/2013-4

Made available in DSpace on 2021-06-25T15:04:37Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-08-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Goiano Federal Institute Although the toxicity of conventional microplastic types (i.e., petroleum derivatives) in different organisms is already known, knowledge about the effects of alternative biopolymers on aquatic vertebrates remains incipient. Thus, the aim of the present study is to test the hypothesis that the exposure of adult Danio rerio individuals to this pollutant for 30 days is enough to cause polylactic acid biomicroplastics (BioMPs of PLA) accumulation in their bodies, which leads to behavioral/neurotoxic, biochemical, and morphological changes. Based on our results, PLA BioMPs at concentrations of 2.5 and 5 mg/L accumulated in the liver, brain, gills and carcass of the assessed animals. However, such an accumulation was not able to cause locomotor damages or to trigger anxiety-like behavior in them. On the other hand, it was enough to cause behavioral changes (in shoal) predictive of co-specific social interaction and antipredatory defensive response deficit likely related to cholinergic changes inferred by increased acetylcholinesterase activity and REDOX imbalance. This imbalance was featured by increased production of reactive species. We observed that the treatments have affected animals' pigmentation pattern. Therefore, our study highlights the toxicological potential of the herein assessed biopolymer, and this finding puts in check the innocuousness of this material, as well as expands our knowledge about how PLA BioMPs can affect the ichthyofauna in freshwater environments. (C) 2021 Elsevier Ltd. All rights reserved. Goiano Fed Univ, Postgrad Program Cerrado Nat Resources Conservat, Urutai Campus, Urutai, Brazil Goiano Fed Inst, Biol Res Lab, Urutai Campus, Urutai, Brazil Univ Fed Uberlandia, Postgrad Program Ecol & Nat Resources Conservat, Uberlandia, MG, Brazil Sao Paulo State Univ, Morphol Dept, Reprod & Mol Biol Grp, Botucatu, SP, Brazil Fed Univ Jatai, Dept Biol Sci, Zebrafish Res & Reprod Lab LABFISH, Jatai, Brazil Univ Sao Paulo, Inst Biomed Sci, Dept Pharmacol, Sao Paulo, Brazil Univ Fed Goias, Postgrad Program Biotechnol & Biodivers, Goiania, Go, Brazil Sao Paulo State Univ, Morphol Dept, Reprod & Mol Biol Grp, Botucatu, SP, Brazil CNPq: 426531/2018-3 Goiano Federal Institute: 23219.001551.2020-92

Made available in DSpace on 2019-10-06T15:23:08Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-02-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Aeromonas hydrophila (Ah) are rod-shaped, Gram-negative, motile aquatic bacteria that can infect fish and mammals, including humans. Due to the importance of this pathogen for fish farming and public health, the present study produced a specific immunoglobulin (Ig) Y by immunizing laying hens with Ah cell proteins. The antibody efficacy in detecting Ah was tested by direct immunofluorescence and indirect immunohistochemistry using tissues from infected Nile tilapia. The produced IgY exhibited specificity and affinity for membrane and cytoplasmic Ah proteins, which enabled detection of the intracellular localization of the bacteria and their proteins within the phagosomes of phagocytes and detection of extracellular bacteria colonizing host tissues. Thus, the findings offer a new perspective on the use of IgY for the diagnosis and analysis of Ah pathogenesis in Nile tilapia. Institute of Chemistry Sao Paulo State University (Unesp) Department of Technology School of Agrarian and Veterinary Sciences Sao Paulo State University (Unesp) Department of Preventive Veterinary School of Agrarian and Veterinary Sciences Sao Paulo State University (Unesp) Institute of Chemistry Sao Paulo State University (Unesp) Department of Technology School of Agrarian and Veterinary Sciences Sao Paulo State University (Unesp) Department of Preventive Veterinary School of Agrarian and Veterinary Sciences Sao Paulo State University (Unesp) CNPq: 140505/2016-4 CNPq: 429245/2016-5

Knowledge about how the COVID-19 pandemic can affect aquatic wildlife is still extremely limited, and no effect of SARS-CoV-2 or its structural constituents on invertebrate models has been reported so far. Thus, we investigated the presence of the 2019-new coronavirus in different urban wastewater samples and, later, evaluated the behavioral and biochemical effects of the exposure of Culex quinquefasciatus larvae to two SARS-CoV-2 spike protein peptides (PSPD-2002 and PSPD-2003) synthesized in our laboratory. Initially, our results show the contamination of wastewater by the new coronavirus, via RT-qPCR on the viral N1 gene. On the other hand, our study shows that short-term exposure (48 h) to a low concentration (40 μg/L) of the synthesized peptides induced changes in the locomotor and the olfactory-driven behavior of the C. quinquefascitus larvae, which were associated with increased production of ROS and AChE activity (cholinesterase effect). To our knowledge, this is the first study that reports the indirect effects of the COVID-19 pandemic on the larval phase of a freshwater invertebrate species. The results raise concerns at the ecological level where the observed biological effects may lead to drastic consequences., Graphical abstract Image 1

Although carbon nanotubes’ (CNTs) toxicity in different experimental systems (in vivoandin vitro) is known, little is known about the toxic effects of carbon nanofibers (CNFs) on aquatic vertebrates. We herein investigated the potential impact of CNFs (1 and 10 mg/L) by usingPhysalaemus cuvieritadpoles as experimental model. CNFs were able to induce nutritional deficit in animals after 48-h exposure to them, and this finding was inferred by reductions observed in body concentrations of total soluble carbohydrates, total proteins, and triglycerides. The increased production of hydrogen peroxide, reactive oxygen species and thiobarbituric acid reactive substances in tadpoles exposed to CNFs has suggested REDOX homeostasis change into oxidative stress. This process was correlated to the largest number of apoptotic and necrotic cells in the blood of these animals. On the other hand, the increased superoxide dismutase and catalase activity has suggested that the antioxidant system of animals exposed to CNFs was not enough to maintain REDOX balance. In addition, CNFs induced increase in acetylcholinesterase and butyrylcholinesterase activity, as well as changes in the number of neuromats evaluated on body surface (which is indicative of the neurotoxic effect of nanomaterials on the assessed model system). To the best of our knowledge, this is the first report on the impact of CNFs on amphibians; therefore, it broadened our understanding about ecotoxicological risks associated with their dispersion in freshwater ecosystems and possible contribution to the decline in the populations of anurofauna species.

The Spike protein (S protein) is a critical component in the infection of the new coronavirus (SARS-CoV-2). The objective of this work was to evaluate whether peptides from S protein could cause negative impact in the aquatic animals. The aquatic toxicity of SARS-CoV-2 spike protein peptides derivatives has been evaluated in tadpoles (n = 50 tadpoles/5 replicates of 10 animals) from species Physalaemus cuvieri (Leptodactylidae). After synthesis, purification, and characterization of peptides (PSDP2001, PSDP2002, PSDP2003) an aquatic contamination has been simulated with these peptides during 24 hours of exposure in two concentrations (100 and 500 ng/mL). The control group (“C”) was composed of tadpoles kept in polyethylene containers containing de-chlorinated water. Oxidative stress, antioxidant biomarkers and AChE activity were assessed. In both concentrations, PSPD2002 and PSPD2003 increased catalase and superoxide dismutase antioxidants enzymes activities, as well as oxidative stress (nitrite levels, hydrogen peroxide and reactive oxygen species). All three peptides also increased acetylcholinesterase activity in the highest concentration. These peptides showed molecular interactions in silico with acetylcholinesterase and antioxidant enzymes. Aquatic particle contamination of SARS-CoV-2 has cholinesterasic effect in P. cuvieri tadpoles. These findings indicate that the COVID-19 can constitute environmental impact or biological damage potential., Graphical abstract

The Spike protein (S protein) is a critical component in the infection of the new coronavirus (SARS-CoV-2). The objective of this work was to evaluate whether peptides from S protein could cause negative impact in the aquatic animals. The aquatic toxicity of SARS-CoV-2 spike protein peptides derivatives has been evaluated in tadpoles (n = 50 tadpoles / 5 replicates of 10 animals) from species Physalaemus cuvieri (Leptodactylidae). After synthesis, purification, and characterization of peptides (PSDP2001, PSDP2002, PSDP2003) an aquatic contamination has been simulatedwith these peptides during 24 hours of exposure in two concentrations (100 and 500 ng/mL). The control group (“C”) was composed of tadpoles kept in polyethylene containers containing de-chlorinated water. Oxidative stress, antioxidant biomarkers and neurotoxicity activity were assessed. In both concentrations, PSPD2002 and PSPD2003 increased catalase and superoxide dismutase antioxidants enzymes activities, as well as oxidative stress (nitrite levels, hydrogen peroxide and reactive oxygen species). All three peptides also increased acetylcholinesterase activity in the highest concentration. These peptides showed molecular interactions in silico with acetylcholinesterase and antioxidant enzymes. Aquatic particle contamination of SARS-CoV-2 has neurotoxics effects in P. cuvieri tadpoles. These findings indicate that the COVID-19 can constitute environmental impact or biological damage potential.HIGHLIGHTSSARS-CoV-2 spike protein peptides (PSDP) were synthesized, purified, and characterized by solid phase peptide synthesis.PSDP peptides promoted REDOX imbalance and acute neurotoxicity in tadpoles (Physalaemus cuvieri)In silico studies have shown interactionsbetween peptides and acetylcholinesterase and antioxidant enzymesAquatic particle contamination of SARS-CoV-2 can constitute additional environmental damageGRAPHICAL ABSTRACT

Made available in DSpace on 2020-12-10T22:00:47Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-12-15 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG) This study aimed to investigate the physical and chemical properties of mucoadhesive zein nanoparticles containing eugenol (NPZMA) and to evaluate their anesthetic effect in immersion baths, their stability in water and their effects on hemogasometric parameters of juvenile Oreochromis niloticus. Four experiments were performed: Experiment 1 characterized the nanoparticles. Experiment 2 evaluated the stability of NPZMA in water using an in vitro test with the following treatments: eugenol-80 mg L-1; NPZMA-80 mg L-1; NPZMA-40 mg L-1, NPZMA-20 mg L-1, water in natura and control (ethyl alcohol was added to the water at a proportion of 1:10 V/V). Experiment 3 tested the same treatments for time of anesthesia induction and recovery. Experiment 4 tested basal (group of non-anesthetized fish), eugenol-80 mg L-1 and NPZMA-40 mg L-1 for hemogasometric variables after two minutes of exposure. The new method for applying eugenol through mucoadhesive zein nanoparticles presented here exhibited positive loads and successful adherence to fish mucus. The method led to changes in water quality during the 60-min observation period, although it remained within the ideal range for O. niloticus. Experiment 3 revealed similar induction times for eugenol-80 mg L-1, NPZMA-80 mg L-1 and NPZMA-40 mg L-1 (P > .05). Recovery time was shortest for NPZMA-20 mg L-1 and longest for NPZMA-80 mg L-1 (P < .05). Experiment 4 found the concentrations tested to have no effects on hemogasometric variables (P > .05). The results demonstrate that mucoadhesive nanoparticles reduced the use of eugenol by 50%, as observed for NPZMA-40 mg L-1. Furthermore, this new form of eugenol application based on mucoadhesive zein nanoparticles showed good stability in water and did not alter hemogasometric parameters of juvenile O. niloticus. Univ Fed Minas Gerais, Dept Zootecnia, Lab Aquacultura, Ave Antonio Carlos 6627, BR-31270901 Belo Horizonte, MG, Brazil Univ Sao Paulo, Inst Ciencias Biol, Dept Farmacol, Ave Prof Lineu Prestes 2415, BR-05508000 Sao Paulo, SP, Brazil Inst & Ctr Pesquisas Sao Leopoldo Mandic, Rua Doutor Jose Rocha Junqueira 13, BR-13045755 Campinas, SP, Brazil Univ Estadual Paulista, Inst Ciencia & Tecnol, Ave Tres Marco,511 Alto Da Boa Vista, BR-18087180 Sorocaba, SP, Brazil Univ Fed Minas Gerais, Inst Ciencias Biol, Dept Morfol, Ave Antonio Carlos 6627, BR-6627 Belo Horizonte, MG, Brazil Univ Estadual Paulista, Inst Ciencia & Tecnol, Ave Tres Marco,511 Alto Da Boa Vista, BR-18087180 Sorocaba, SP, Brazil CNPq: 308547/2018-7

Malaria affects more than 200 million people annually around the world, killing a child every 2 min. Artemether (ART) and lumefantrine (LUM) are the gold standard choice to treat uncomplicated Plasmodium falciparum malaria; however, they are hydrophobic compounds with low oral bioavailability. Microneedle (MN) arrays consist of micron-sized needles on one side of a supporting base and have the ability to bypass the skin's stratum corneum barrier in a minimally invasive way, creating temporary channels through which drugs can diffuse, including those with poor water solubility. Herein, we report the development of dissolving MNs (DMNs) containing ART (MN-ART) and LUM (MN-LUM) as an alternative treatment regimen for malaria in low-resource settings. To incorporate the drugs into the MNs, nanosuspensions (NSs) for both molecules were developed separately to enhance drug solubility. The NSs were freeze-dried and the powder form was incorporated directly in an aqueous polymeric blend with poly-vinyl-pyrrolidone for MN-ART and a sodium hyaluronate hydrogel for MN-LUM. The in vivo bioavailability studies were performed using a MN reapplication scheme (1 × a day for 3 days), illustrating that an extended-release profile was achieved for both drugs when MNs were applied intradermally, and when compared to conventional oral treatment. The ART-LUM oral treatment was used as a positive control. For antimalarial activity, studies with animals infected with 106 Plasmodium yoelii 17XNL (12 days) were also conducted using female C57BL/6JUnib mice, demonstrating a 99.5% reduction in parasitemia by day 12 post-infection. By abolishing the infection, MN-ART and MN-LUM may serve as a promising controlled intradermal delivery device for antimalarial drugs to be explored in endemic areas.

We aim at evaluating the toxicity of naturally-aged polystyrene microplastics (MPs) in Danio rerio at intermediate development stage. Animal models were stactically exposed to 4 × 104 and 4 × 106 microparticles/m3 for five days – this concentration is environmentally relevant. We evaluated MP’s impact on animals’ nutritional status and REDOX balance, as well as its potential neuro- and cytotoxic action on them. Initially, MPs did not induce any change in total carbohydrates, triglycerides and total cholesterol levels. MP accumulation was associated with oxidative stress induction, which was inferred by the nitrite and thiobarbituric acid reactive substances levels. Furthermore, we observed that such stress was not counterbalanced by increase in the assessed enzymatic (total glutathione, catalase and superoxide dismutase) and non-enzymatic (total thiols, reduced glutathione and DPPH radical scavenging activity) antioxidants. The association between high acetylcholinesterase activity and numerical changes in neuroblasts distributed on animals' body surface confirmed MP’s neurotoxic potential. MP’s ability to induce apoptosis and necrosis processes in animals' erythrocytes suggested its cytotoxic action; therefore, the present study is pioneer in providing insight on how MPs can affect young freshwater fish at environmental concentrations. It is essential knowing the magnitude of these pollutants’ impact on the ichthyofauna.

SummaryEstablishing new experimental animal models to assess the safety and immune response to the antigen used in the development of COVID-19 vaccine is an imperative issue. Based on the advantages of using zebrafish as a model in research, herein we suggest doing this to test the safety of the putative vaccine candidates and to study immune response against the virus. We produced a recombinant N-terminal fraction of the Spike SARS-CoV-2 protein and injected it into adult female zebrafish. The specimens generated humoral immunity and passed the antibodies to the eggs. However, they presented adverse reactions and inflammatory responses similar to severe cases of human COVID-19. The analysis of the structure and function of zebrafish and human Angiotensin-converting enzyme 2, the main human receptor for virus infection, presented remarkable sequence similarities. Moreover, bioinformatic analysis predicted protein-protein interaction of the Spike SARS-CoV-2 fragment and the Toll-like receptor pathway. It might help in the choice of future therapeutic pharmaceutical drugs to be studied. Based on the in vivo and in silico results presented here, we propose the zebrafish as a model for translational research into the safety of the vaccine and the immune response of the vertebrate organism to the SARS-CoV-2 virus.

Made available in DSpace on 2021-06-25T11:46:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-02-20 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Instituto Federal Goiano Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundacao de Amaparo a Pesquisa do Estado de Goias (FAPEG, Brazil) Artemisinin extracted from Artemisia annua L. plants has a range of properties that qualifies it to treat several diseases, such as malaria and cancer. However, it has short half-life, which requires making continuous use of it, which has motivated the association of artemisinin (ART) with polymeric nanoparticles to increase its therapeutic efficiency. However, the ecotoxicological safety of this association has been questioned, given the scarcity of studies in this area. Thus, in this work the toxicity of Poly (epsilon-Caprolactone) nanocapsules added with ART (ART-NANO) in zebrafish (Danio rerio), embryos and adults was studied. Different endpoints were analyzed in organisms exposed to ART-NANO, including those predictive of embryotoxicity and histopatoxicity. Embryotoxicity was analyzed based on Organization for Economic Co-operation and Development (OECD) test guideline (236) for fish embryo acute toxicity applied to zebrafish (Danio rerio) at 96 hpf under five nominal logarithmic concentrations (0.125 to 2.0 mg/L). Our results demonstrate, mainly, that fertilized eggs presented increased coagulation, lack of heart rate, vitelline sac displacement and lack of somite formation. On the other hand, adult individuals (exposed to the same concentrations and evaluated after 24 and 96 h of exposure) have shown increased pericarditis. Therefore, the treatment based on ART, poly (epsilon-caprolactone) nanocapsules and on their combination at different concentrations have shown toxic effects on zebrafish embryos and adult individuals. (C) 2020 Elsevier B.V. All rights reserved. Univ Sao Paulo, Biomed Sci Inst, Pharmacol Dept, Sao Paulo, SP, Brazil Fed Univ Rio Janeiro UFRJ, Biodivers & Sustainabil Inst NUPEM, Integrated Translat Biosci Lab LIBT, Macae, RJ, Brazil Univ Fed Sao Carlos, Dept Genet & Evolut, Sao Carlos, SP, Brazil Univ Estadual Campinas, Pharmaceut Sci Sch, Campinas, SP, Brazil Univ Fed Minas Gerais, Belo Horizonte, MG, Brazil Sao Paulo State Univ, Jaboticabal, SP, Brazil Univ Fed Alfenas, Motric Sci Inst, Alfenas, MG, Brazil Livestock & Supply, Minist Agr, Sao Carlos, SP, Brazil Sao Paulo State Univ, Botucatu, SP, Brazil Goiano Fed Inst, Biol Sci Dept, Urutai, Go, Brazil Sao Paulo State Univ, Jaboticabal, SP, Brazil Sao Paulo State Univ, Botucatu, SP, Brazil CNPq: 426531/2018-3 Instituto Federal Goiano: 23219.000865.2020-78 CNPq: 307743/2018-7

Blood tissue has been used to assess animal health and the environment in which they live. This tissue is easily acquired and has the ability to respond to various adverse conditions. Several techniques have been employed in the detection of xenobiotic-induced cell damage in blood cells. In general, traditionally used technologies, such as cellular analysis in blood smears, are time-consuming and require great analytical capacity. The present study proposes flow cytometry as a method to detect changes in blood cell populations. Tilapia (Oreochromis niloticus) was selected as a model for plotting the profile of fish blood cell populations after exposure to xenobiotics without euthanizing animals or using cell markers. Populations of erythrocytes and lymphocytes were detected only by combining the techniques of FACSAria cell sorting and light microscopy. Systemic deleterious effects were found through blood analysis, such as an increased lymphocyte-rich population at 48 h of exposure followed by a subsequent decrease. Moreover, the time-dependent expression of Nrf2 suggests its participation in increased membrane disruption, indicating it has a central role in erythrocyte lifespan. The present results shed light on the viability of using flow cytometry for blood analysis of living fish.

Made available in DSpace on 2021-06-25T10:13:13Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-12-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) In order to understand events and mechanisms present in the pathophysiology of tilapia's chronic inflammation and based on the immunomodulatory activity attributed to cyclophosphamide which is widely used to suppress immune responses in human medicine, the present study investigated the effects of cyclophosphamide (CYP) treatment on the modulation of foreign body inflammatory reaction in Nile tilapia (Oreochromis niloticus) with round glass coverslip implanted in the subcutaneous tissue (9 mm of diameter). Forty tilapia (151 ± 10,2 g) were randomly distributed in 5 aquariums (n = 8) with a capacity of 250 L of water each, to compose two treatments (sampled 3 and 6 days post-implantation): implanted/untreated (control) and implanted/treated with 200 mg of CYP kg−1 of b.w., through i.p. route. A fifth group (n = 8) was sampled without any stimulus (naive) to obtain reference values. CYP-treated tilapia showed decrease in macrophage accumulation, giant cell formation and Langhans cells on the glass coverslip when compared to control fish. The treatment with CYP resulted in decrease of leukocyte and thrombocyte counts. Decrease in alpha-2-macroglobulin, ceruloplasmin, albumin and transferrin levels, as well as increase in haptoglobin, complement C3 and apolipoprotein A1 were observed in tilapias during foreign body inflammation. Blood levels of complement C3, alpha-2-macroglobulin, ceruloplasmin and transferrin were modulated by treatment with CYP. Therefore, the treatment with 200 mg of CYP kg−1 of b.w. in tilapia resulted in an anti-inflammatory effect by suppressing the dynamics between leukocytes in the bloodstream and macrophage accumulation with giant cell formation in the inflamed focus, as well as by modulating APPs during foreign body reaction. Department of Pharmacology Institute of Biomedical Science University of São Paulo (USP) Department of Preventive Veterinary Medicine São Paulo State University (UNESP) Veterinary College Federal University of Rondonia (UNIR) Department of Graduate Program in Health Sciences Federal University of Roraima (UFRR) Laboratório de Bioquímica de Peptídeos UNIFESP Laboratory of Animal Pharmacology and Toxicology Brasil University Department of Preventive Veterinary Medicine São Paulo State University (UNESP) FAPESP: 2012/12256-7 FAPESP: 2013/11675-9 CNPq: 432830/2016-2 CNPq: 477816/2013-4

Made available in DSpace on 2021-06-25T11:04:32Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-09-01 Mucoadhesive polymeric nanocapsules have attracted interest of researchers from different fields from natural sciences because of their ability to interact with the mucosa and increase drug permeation. Anesthesia by immersion causes absorption through the skin and gills of fish, so it is important to evaluate the exposure of these organs to drug nanosystems. Benzocaine (BENZ) is one of the most popular anesthetic agents used in fish anesthesia, but it has drawbacks because of its low bioavailability, resulting in weak absorption after immersion. Here we describe method developed for preparing and characterizing chitosan-coated PLGA mucoadhesive nanoparticles containing BENZ (NPMAs) for zebrafish immersion anesthesia. We determined the lowest effective concentration, characterized the interaction of the mucoadhesive system with fish, measured the anesthetic efficacy, and evaluated possible toxic effects in embryos and adults exposed to the nanoformulations. This study opens perspectives for using nanoformulations prepared with BENZ in aquaculture, allowing reduction of dosage as well as promoting more effective anesthesia and improved interaction with the mucoadhesive system of fish. Department of Pharmacology University of São Paulo-ICB/USP Laboratório Integrado de Biociências Translacionais (LIBT) Instituto de Biodiversidade e Sustentabilidade (NUPEM) Universidade Federal do Rio de Janeiro (UFRJ) Department of Morphology ICB-UFMG Aquiculture Laboratory (Laqua) UFMG Department of Preventive Veterinary Medicine São Paulo State University Department of Postgraduate in Health Sciences PROCISA Federal University of Roraima (UFRR) Institute of Chemistry São Paulo State University (Unesp) Laboratory of Animal Pharmacology and Toxicology Brasil University Department of Clinical and Toxicological Analyses Faculty of Pharmacy-UFMG Laboratory of Applied Immunology Federal University of São Carlos School of Veterinary Medicine Department of Clinic and Veterinary Surgery UFMG Faculty of Medicine São Leopoldo Mandic Institute of Science and Technology of Sorocaba São Paulo State University Department of Preventive Veterinary Medicine São Paulo State University Institute of Chemistry São Paulo State University (Unesp) Institute of Science and Technology of Sorocaba São Paulo State University

Morphological nuclear alterations are indicative of DNA damage and have been considered excellent markers of exposure to several pollutants in aquatic environments. Flow cytometry is a powerful technique for measuring cell phenotypes in large numbers of cells in a short period of time. This technique is suited to the study of cell populations and subset identification as a function of its high-throughput and multi-parameter characteristics. We used the quantification of erythrocyte nuclear alterations to compare the techniques of imaging flow cytometry and light microscopy. The comparison used blood samples of the fish Oreochromis niloticus assayed using cadmium as a nuclear alteration-inducing agent. The results showed that imaging flow cytometry has higher sensitivity than light microscopy for detecting and quantifying erythrocytic nuclear alterations. We conclude that imaging flow cytometry can produce fast and reliable results and could potentially be useful in studies involving fish erythrocytes under normal and impacted environmental conditions.

Severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) causes the infectious disease COVID-19 (coronavirus disease 2019), which was first reported in Wuhan, China, in December 2019. Despite extensive efforts to control the disease, COVID-19 has now spread to more than 100 countries and caused a global pandemic. SARS-CoV-2 is thought to have originated in bats; however, the intermediate animal sources of the virus are unknown. In this study, we investigated the susceptibility of ferrets and animals in close contact with humans to SARS-CoV-2. We found that SARS-CoV-2 replicates poorly in dogs, pigs, chickens, and ducks, but ferrets and cats are permissive to infection. Additionally, cats are susceptible to airborne transmission. Our study provides insights into the animal models for SARS-CoV-2 and animal management for COVID-19 control.

The present study evaluated whether a natural dietary additive, dried Artemisia annua leaves, may be useful to control Rhipicephalus (Boophilus) microplus on naturally infested cattle. Twenty heifers of the Canchim breed, weighing around 250 kg, were divided into two equally sized experimental groups: 1) control animals and 2) animals receiving 200 g/day of dried A. annua leaves for two months. Before treatment began, the animals were homogeneously distributed in control and treatment groups based on their pre-treatment weight and tick infestation level. Counts of engorged female ticks then occurred weekly during the two-month experimental period. We also monitored cattle weight gain and packed cell volume (PCV). Artemisinin (0.96%) was quantified in the plant material by high-performance liquid chromatography with refractive index detector (HPLC-IR). No statistical differences between the control and treatment groups were observed for engorged female counts (log averages of 1.3 ticks and 1.4 ticks per animal, respectively), daily cattle weight gain (0.910 kg and 0.888 kg, respectively) or PCV (33.5% and 33.0%, respectively). We conclude that the oral supplementation of cattle feed with dried A. annuna leaves did not control natural infestation of R. (B.) microplus. The hypothesis of artemisinin’s action on cattle ticks by ingestion through the animals’ blood was not confirmed at the evaluated dose.