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1.
Adv Rheumatol ; 62(1): 27, 2022 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-35869515

RESUMO

INTRODUCTION/OBJECTIVES: Clinical evidence of skeletal muscle involvement is not uncommon in systemic lupus erythematosus (SLE). Because of the poor understanding of signaling pathways involved in SLE muscle wasting, the  aim of this study was to evaluate the effects of vitamin D supplementation on skeletal muscle in mice with pristane-induced lupus. METHODS: Balb/c mice with lupus-like disease induced by pristane injection were randomized into three groups: pristane-induced lupus (PIL; n = 10), pristane-induced lupus + vitamin D supplementation (PIL + VD; n = 10) and healthy controls (CO; n = 8). Physical function was evaluated on days 0, 60, 120 and 180. The tibialis anterior and gastrocnemius muscles were collected to evaluate myofiber cross-sectional area (CSA) and protein expression. RESULTS: The PIL + VD group showed lower muscle strength compared to the CO and PIL groups at different time points. PIL mice showed similar myofiber CSA compared to CO and PIL + VD groups. LC3-II expression was higher in PIL compared to CO and PIL + VD groups. MyoD expression was higher in PIL mice compared to PIL + VD, while myostatin expression was higher in PIL + VD than PIL group. Myogenin expression levels were decreased in the PIL + VD group compared with the CO group. The Akt, p62 and MuRF expressions and mobility assessment showed no significance. CONCLUSIONS: Changes in skeletal muscle in PIL model happen before CSA reduction, possibly due to autophagy degradation, and treatment with Vitamin D has a impact on physical function by decreasing muscle strength and time of fatigue.. Vitamin D supplementation has a potential role modulating physical parameters and signaling pathways in muscle during pristane-induced lupus model.


Assuntos
Lúpus Eritematoso Sistêmico , Vitamina D , Animais , Autofagia , Suplementos Nutricionais , Modelos Animais de Doenças , Lúpus Eritematoso Sistêmico/induzido quimicamente , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Camundongos , Terpenos/toxicidade , Vitamina D/uso terapêutico
2.
Compr Rev Food Sci Food Saf ; 20(1): 48-90, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33443807

RESUMO

Alternatives to the use of conventional veterinary drugs in food-producing animals have gained attention, such as the use of natural products (NPs), mainly to soften the risks to the animal, the environment, and consumer's health. Although NPs have consistent advantages over conventional drugs, they cannot be considered risk free under food safety matters. In this way, this document presents a comprehensive overview of the importance of considering both the pharmacological and toxicological properties of the constituents of a NP from plants intending the standardization and regulation of its use in food-producing animals. Terpenes are the most diverse class of natural substances present in NP of vegetal origin with a broad range of biological activities that can be explored in veterinary science; however, certain plants and terpenes also have significant toxic effects, a fact that can harm the health of animals and consequently generate economic losses and risks for humans. In this context, this review gathered scientific data of vegetal species of importance to ethnoveterinary for food-producing animals, which produce terpenes, its biological effects, and their implications on food safety issues for consumers. For this, more than 300 documents were selected from different online scientific databases. The present data and discussion may contribute to the rational commercial exploration of this class of NPs in veterinary medicine.


Assuntos
Plantas Medicinais , Drogas Veterinárias , Animais , Inocuidade dos Alimentos , Humanos , Fitoterapia , Terpenos/toxicidade
3.
Biosci. j. (Online) ; 36(Supplement1): 228-237, Dec. 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1355252

RESUMO

The present work aimed to determine the toxicity of linalool and evaluate the lethal and toxic effects of linalool associated with pyrethroids in binary mixtures to fall armyworm (Spodoptera frugiperda). The insects used in the experiment were obtained from stock breeding initiated from larvae collected from conventional corn plants, grown in an experimental area, in the city of Uberlândia, Minas Gerais. Also, it was obtained essential oil from a variety of Ocimum basilicum, with a high content of linalool (80%), found naturally, as a measure of comparison of different linalool (97.5%) assays. Dose-response bioassays with 3rd instar larvae were performed to determine lethal dose for 50% mortality (LD50) of linalool. Toxicity tests were also performed with O. basilicum essential oil and with pyrethroid insecticides: deltamethrin and its commercial product (Decis 25 EC, Bayer®). After this, combinations between different doses of these products were made and applied on 3rd instar larvae of Spodoptera frugiperda (Smith). Linalool presented high toxicity to S. frugiperda (LD50 = 0.177 µL a.i. µL-1). It was observed neurotoxic effects after the linalool application since the insects presented an aspect of confusion, followed by extreme agitation and finally death. All binary mixtures caused mortality higher than the products applied alone (deltamethrin and linalool) used at 100% LD50, except to 75% LD50 deltamethrin added to 25% LD50 linalool, whose mortality did not differ the products alone, in 24 hours. It was obtained over 90% larval mortality when linalool was combined with 25% LD50 of deltamethrin, in 24 and 48 hours after application, and over 80% of mortality when linalool was combined with 25% LD50 of Decis, only in 48 hours after application. We conclude that linalool is a potential insecticidal and can be associated with pyrethroids to control of S. frugiperda. Further studies are required in order to evaluate the synergistic combinations against field populations of S. frugiperda.


O objetivo deste trabalho foi determinar a toxicidade do linalol e avaliar os efeitos tóxicos e letais do linalol associado a piretroides em misturas binárias para lagarta do cartucho do milho (Spodoptera frugiperda). Os insetos utilizados no experimento foram obtidos de criação estoque iniciada a partir de larvas coletadas em plantas de milho convencional, cultivado em área experimental, no município de Uberlândia, Minas Gerais. Também foi obtido óleo essencial de uma variedade de Ocimum basilicum, com alto teor de linalol (80%), encontrado naturalmente, como medida de comparação para ensaios com linalol (97.5%). Os bioensaios do tipo dose-resposta com larvas de 3º instar foram realizados para determinar a dose letal do linalol para 50% de mortalidade da população (DL50). Também foram realizados testes de toxicidade com óleo essencial de Ocimum basilicum e com inseticidas piretroides: deltametrina e seu produto comercial (Decis 25 EC, Bayer®). Em seguida, foram realizadas combinações entre diferentes doses desses produtos e aplicadas em larvas de 3º instar de Spodoptera frugiperda (Smith). De acordo com os resultados, observou-se que o linalol apresentou alta toxicidade para S. frugiperda (DL50 = 0,177 µL a. i. µL-1). Foram observados efeitos neurotóxicos após a aplicação do linalol, uma vez que os insetos apresentaram um aspecto de confusão, seguido de extrema agitação e, por fim, morte. Todas as combinações binárias causaram mortalidade maior que os produtos aplicados isoladamente (deltametrina e linalol) utilizando-se 100% da DL50, exceto para 75% DL50 de deltametrina somada a 25% DL50 de linalol, cuja mortalidade não diferiu dos produtos isolados, em 24 horas após a aplicação. Foi obtida mais de 90% de mortalidade de larvas quando se combinou linalol com 25% da DL50 de deltametrina, em 24 e 48 horas após a aplicação, e mais de 80% de mortalidade quando se combinou linalol com 25% da DL50 do produto comercial, somente 48 horas após a aplicação. Concluímos que o linalol é um potencial inseticida e pode ser associado a piretroides no controle de S. frugiperda. Mais estudos são necessários em vista de avaliar as combinações sinérgicas contra populações de campo de S. frugiperda.


Assuntos
Piretrinas/toxicidade , Terpenos/toxicidade , Spodoptera/efeitos dos fármacos , Sinergismo Farmacológico
4.
Molecules ; 25(7)2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-32230839

RESUMO

The research of natural products has allowed for the discovery of biologically relevant compounds inspired by plant secondary metabolites, which contributes to the development of many chemotherapeutic drugs used in cancer treatment. Psidium guajava leaves present a diverse phytochemical composition including flavonoids, phenolics, meroterpenoids, and triterpenes as the major bioactive constituents. Guajadial, a caryophyllene-based meroterpenoid, has been studied for potential anticancer effects tested in tumor cells and animal experimental models. Moreover, guajadial has been reported to have a mechanism of action similar to tamoxifen, suggesting this compound as a promisor phytoestrogen-based therapeutic agent. Herein, the anti-estrogenic action and anti-proliferative activity of guajadial is reported. The enriched guajadial fraction was obtained by sequential chromatographic techniques from the crude P. guajava dichloromethane extract showing promising anti-proliferative activity in vitro with selectivity for human breast cancer cell lines MCF-7 and MCF-7 BUS (Total Growth Inhibition = 5.59 and 2.27 µg·mL-1, respectively). Furthermore, evaluation of anti-estrogenic activity in vivo was performed demonstrating that guajadial enriched fraction inhibited the proliferative effect of estradiol on the uterus of pre-pubescent rats. These results suggest a relationship between anti-proliferative and anti-estrogenic activity of guajadial, which possibly acts in tumor inhibition through estrogen receptors due to the compounds structural similarity to tamoxifen.


Assuntos
Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Antagonistas de Estrogênios/farmacologia , Extratos Vegetais/química , Folhas de Planta/química , Psidium/química , Terpenos/farmacologia , Animais , Antineoplásicos/uso terapêutico , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Ovário/efeitos dos fármacos , Ratos , Sesquiterpenos/química , Sesquiterpenos/farmacologia , Sesquiterpenos/uso terapêutico , Sesquiterpenos/toxicidade , Terpenos/química , Terpenos/uso terapêutico , Terpenos/toxicidade , Útero/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Drug Chem Toxicol ; 43(4): 435-440, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30889987

RESUMO

Citral, 3,7-dimethyl-2,6-octadien-1-al, one of the main components of the essential oils obtained from several plants, is used as a food additive and as a fragrance for detergents, cosmetics and other toiletries. The literature shows disparity regarding citral genotoxicity. Thus, the main objective of our work was to evaluate the genotoxic effects of citral in human cell cultures, HepG2 and leukocytes. Cytotoxicity assays (trypan blue and MTT) showed citral toxic effects in HepG2 cells (with metabolizing liver enzymes), which contrasted with the absence of toxicity in leukocytes. After citral exposure, both cell types did not demonstrate clastogenic/aneugenic effects in the micronucleus test. However, for the comet assay, citral exposure lead to significant genotoxic effects in both HepG2 (even to citral low concentrations) and leukocytes. The use of citral must be viewed with caution due to its ability to induce DNA damages, especially after being metabolized by cells with active liver enzymes.


Assuntos
Monoterpenos Acíclicos/toxicidade , Citotoxinas/toxicidade , Dano ao DNA , Mutagênicos/toxicidade , Óleos de Plantas/toxicidade , Terpenos/toxicidade , Células Hep G2 , Humanos , Leucócitos/efeitos dos fármacos
6.
Environ Pollut ; 251: 591-599, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31108292

RESUMO

The ecological and economic contributions of pollinator bees to agricultural production have been threatened by the inappropriate and excessive use of pesticides. These pesticides are often applied in areas with ecological peculiarities (e.g., the Neotropical savannah-like region termed as Cerrado) that were not considered during the product development. Here, we conducted field experiments with melon (i.e., Cucumis melo L.) plants cultivated under Brazilian Cerrado conditions and evaluated the impacts of botanical (i.e., neem-based insecticide) and synthetic (i.e., the pyrethroid insecticide deltamethrin and the fungicides thiophanate-methyl and chlorothalonil) pesticides on the flower visitation rates of naturally occurring pollinator bees. Our results revealed that both honey bees (i.e., Apis mellifera L.) and non-Apis bees visited melon flowers and the intensity of bee visitation was moderately correlated with yield parameters (e.g., number of marketable fruits and fruit yield). Pesticide treatments differentially affected bee species. For instance, Plebeia sp. bees were not affected by any pesticide treatment, whereas both A. mellifera and Halictus sp. bees showed reduced visitation intensity after the application of deltamethrin or neem-based insecticides. Fungicide treatment alone did not influence the bee's visitation intensity. Deltamethrin-treated melon fields produced significantly lighter marketable fruits, and the melon yield was significantly lower in melon fields treated with the neem-based insecticide. Thus, our findings with such pollinator bees reinforce the idea that field applications of botanical pesticides may represent as risky as the applications of synthetic compounds, indicating that these alternative products should be submitted to risk assessments comparable to those required for synthetic products.


Assuntos
Abelhas/efeitos dos fármacos , Comportamento Animal/efeitos dos fármacos , Cucurbitaceae/crescimento & desenvolvimento , Flores/crescimento & desenvolvimento , Inseticidas/toxicidade , Polinização , Animais , Abelhas/fisiologia , Brasil , Glicerídeos/toxicidade , Polinização/efeitos dos fármacos , Piretrinas/toxicidade , Terpenos/toxicidade
7.
Sci Total Environ ; 677: 57-67, 2019 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-31051383

RESUMO

Sustainable agriculture encourages practices that present low risks to the environment and human health. To this end, zein (corn protein) can be used to develop nanocarrier systems capable of improving the physicochemical properties of biopesticides, reducing their possible toxicity. Neem oil extracted from the Azadirachta indica tree contains many active ingredients including azadirachtin, which is the active ingredient in multiple commercially available biopesticides. In this study, we describe the preparation and characterization of neem oil-loaded zein nanoparticles, together with evaluation of their toxicity towards nontarget organisms, using Allium cepa, soil nitrogen cycle microbiota, and Caenorhabditis elegans aiming to achieve the safer by design strategy. The spherical nanoparticles showed an average diameter of 278 ±â€¯61.5 nm and a good stability during the experiments. In the toxicity assays with A. cepa, the neem oil-loaded zein nanoparticles mitigated the increase in the DNA relative damage index caused by the neem oil. Molecular genetic analysis of the soil nitrogen cycle microbiota revealed that neem oil-loaded zein nanoparticles did not change the number of genes which encode nitrogen-fixing enzymes and denitrifying enzymes. In C. elegans, the neem oil-loaded zein nanoparticles had no toxic effect, while neem oil interfered with pharyngeal pumping and GST-4 protein expression. These neem oil-loaded zein nanoparticles showed promising results in the toxicity studies, opening perspectives for its use in crop protection in organic agriculture.


Assuntos
Caenorhabditis elegans/efeitos dos fármacos , Glicerídeos/toxicidade , Microbiota/efeitos dos fármacos , Cebolas/efeitos dos fármacos , Praguicidas/toxicidade , Terpenos/toxicidade , Animais , Ecotoxicologia , Nanopartículas/toxicidade , Ciclo do Nitrogênio , Microbiologia do Solo , Testes de Toxicidade
8.
Ecotoxicol Environ Saf ; 163: 28-36, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30031942

RESUMO

The recent decline of Apis mellifera populations around the world has been subject of intense research due to ecological and economic damages resulting from the loss of pollination services. The intensive use of insecticides from the neonicotinoids group is among the possible causal factors of this decline, including also sub-lethal effects. However, the use of synthetic insecticides has been increased on a global scale in the recent decades. In order to evaluate an alternative to the use of neonicotinoids, this work investigated the effects of a bioinsecticide and its major compound on A. mellifera (Apidae: Hymenoptera), one of the main pollinators of crop plants. For this, bees were exposed, by contact and ingestion, to the essential oil of Cymbopogon martinii (Poaceae: Poales), to geraniol (major compound) and the insecticide imidacloprid to evaluate the toxicity and behavioral effects as well as the locomotion changes and immune responses of bees treated with these compounds. In general, toxicity was greater through ingestion and the insecticide imidacloprid was more toxic to A. mellifera compared to the essential oil and its major compound. The individual and collective behaviors (i.e. trophallaxis, grooming, avoidance) as well as the immune responses of bees were not significantly affected by bioinsecticides. However, the locomotion response and flight orientation of the bees were significantly altered by insecticide when administered by ingestion. Our results highlight the potential of C. martinii essential oil and its major compound as a possible alternative to mitigate the harmful effects of neonicotinoids on bees.


Assuntos
Abelhas/efeitos dos fármacos , Cymbopogon , Inseticidas/toxicidade , Neonicotinoides/toxicidade , Nitrocompostos/toxicidade , Óleos Voláteis/toxicidade , Terpenos/toxicidade , Monoterpenos Acíclicos , Animais , Abelhas/fisiologia , Comportamento Animal/efeitos dos fármacos , Locomoção/efeitos dos fármacos , Polinização/efeitos dos fármacos
9.
Neotrop Entomol ; 47(2): 311-317, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28762217

RESUMO

The search for new safer insecticides has increased in recent agriculture. Botanical compounds such as terpenoids and plant essential oils with insecticidal activity could represent important tools in pest management, and their risk assessment against non-target organisms is necessary since they may serve as a precursor for the synthesis of new insecticide active ingredients. For this study, the acute toxicity and sublethal effects of seven terpenoids and three essential oils with recognized insecticidal activity were evaluated on the predator Chrysoperla externa (Hagen) (Neuroptera: Chrysopidae) in laboratory bioassays. Results indicate that these compounds feature relative selectivity to the predator C. externa; however, sublethal effects on reproduction were recorded for some compounds. The phenolic monoterpenoids carvacrol and thymol were more acutely toxic than other terpenoids screened, with LD50 <20,000 µg/g; however, they were less toxic than natural pyrethrins (toxicity standard) in these bioassays. Sublethal effects on fecundity and fertility were observed for R-(+)-limonene, while oregano oil only affected fecundity. The compounds evaluated here have potential to be used as insecticides and can serve as backbone for future synthesis of selective active ingredients; however, a complete risk assessment to C. externa and other non-target organisms is necessary for their incorporation in future crop protection paradigms.


Assuntos
Inseticidas/toxicidade , Neópteros/efeitos dos fármacos , Óleos Voláteis/toxicidade , Terpenos/toxicidade , Animais , Agentes de Controle Biológico , Feminino , Fertilidade , Larva/efeitos dos fármacos , Dose Letal Mediana
10.
Genet Mol Res ; 16(3)2017 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-28973756

RESUMO

Geraniol is an acyclic monoterpene alcohol present in the essential oil of many aromatic plants and is one of the most frequently used molecules by the flavor and fragrance industries. The literature also reports its therapeutic potential, highlighting itself especially as a likely molecule for the development of drugs against cancer. In view of these considerations, this study was designed to evaluate the cytotoxic and genotoxic potential of geraniol, in an in vitro protocol, using two types of human cells: one without the ability to metabolize (peripheral blood mononuclear cells - PBMC), and the other with this capability (human hepatoma cell line - HepG2) through the comet assay and the micronucleus test. Four concentrations (10, 25, 50, and 100 µg/mL) were selected for the genotoxic assessment for PBMC and three (1.25, 2.5, and 5 µg/mL) for HepG2 cells based on cytotoxicity tests (MTT assay). Results showed that geraniol did not present genotoxic or clastogenic/aneugenic effects on both cell types under the conditions studied. However, caution is advised in the use of this substance by humans, since a significant reduction in viability of HepG2 and a marked decrease in cell viability on normal PBMC were verified.


Assuntos
Dano ao DNA , Monócitos/efeitos dos fármacos , Terpenos/toxicidade , Monoterpenos Acíclicos , Células Hep G2 , Humanos
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