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1.
J Ethnopharmacol ; 305: 116121, 2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-36599374

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Currently, there is a remarkable increase in the consumption of microgreens, (young edible vegetables or herbs), as potential nutraceuticals for the management of diseases. Brassica carinata A. Braun is one of the traditional leafy vegetables cultivated in various parts of Sub- Saharan Africa. The plant is revered for its efficacy in the treatment of wounds and gastrointestinal disorders among other medicinal benefits. It is therefore crucial to characterize Brassica carinata microgreens for their phytoconstituents and ascertain their safety for use. AIM OF THE STUDY: The study evaluated the oral acute and subacute toxicity of Brassica carinata microgreens ethanol extract (BMEE) in Wistar rats and identification of its chemical composition and profile. MATERIALS AND METHODS: For acute toxicity (14 days), rats were grouped into four and received a single oral dose, the control group received distilled water, while others received 500 mg/kg, 1000 mg/kg, and 2000 mg/kg of BMEE. For the subacute toxicity (28 days), rats in four groups received daily doses of 250 mg/kg, 500 mg/kg or 1000 mg/kg and distilled water. Daily clinical observations like lethargy and mortality were conducted. Hematological, biochemical, and histopathological evaluations were performed at the end of each experiment. Phytochemical profile was determined using a UV-VIS spectrophotometer and Gas Chromatography coupled to Mass Spectrometry (GC-MS) analysis determined the potential bioactive components in the microgreens extract. RESULTS: In both acute and sub-acute toxicity studies, no mortalities, indications of abnormality, or any treatment related adverse effects were observed at doses of 2000 mg/kg, 1000 mg/kg, 500 mg/kg, and 250 mg/kg. The LD50 of BMEE was above 2000 mg/kg. No significant (p > 0.05) changes in the hematological and biochemical parameters of the treated groups compared to the control groups in both studies. Histopathological examination of the liver, kidney, lungs, and heart revealed a normal architecture of the tissues in all the treated animals. Phytochemical analyses revealed the presence of flavonoids (most abundant), phenols and alkaloids. Phytol, linoleic acid, and 9,12,15-octadecatrienoic acid, among other compounds, were identified by GC-MS analysis. CONCLUSION: The results showed that B. carinata microgreens ethanol extract is nontoxic and found to have several compounds with reported pharmacological significance suggesting safety for use.


Assuntos
Brassica , Extratos Vegetais , Ratos , Animais , Ratos Wistar , Extratos Vegetais/química , Testes de Toxicidade Aguda , Etanol , Compostos Fitoquímicos/toxicidade , Água , Testes de Toxicidade Subaguda
2.
Toxins (Basel) ; 14(11)2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36355985

RESUMO

The present study aimed to evaluate the acute and subacute toxicity profiles of Erodium guttatum extracts in mice using the methods described in the guidelines of the OECD. In the acute toxicity study, the LD50 value was greater than 2000 mg/kg. The subacute toxicity study of E. guttatum extracts showed no significant changes in body or organ weights. The administration of E. guttatum extracts to mice at a dose of 200 mg/kg led to an increase in white blood cells, platelets and hemoglobin. Moreover, the aqueous extract of E. guttatum only decreased liver aspartate aminotransferase (ASAT) levels at a dose of 200 mg/kg, and creatinine and urea levels did not show any significant alterations compared to the control group. Our results showed that the extracts of E. guttatum caused a slight increase in alanine aminotransferase (ALAT) and triglycerides. The histological study showed that mice treated with E. guttatum extracts experienced some histopathological changes in the liver, particularly with the methanolic extract, and slight changes in the kidneys and pancreas. Regarding the renal profile, no toxicity was observed. These results provide basic information on the toxicological profile of E. guttatum used in traditional medicine.


Assuntos
Extratos Vegetais , Roedores , Animais , Camundongos , Testes de Toxicidade Aguda , Extratos Vegetais/toxicidade , Dose Letal Mediana , Administração Oral
3.
Aquat Toxicol ; 253: 106321, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36308821

RESUMO

Cyanobacteria and their toxic metabolites present a global threat to water habitats, but their impact on aquatic organisms in a multistress environment has been poorly investigated. Here we present the results of a survey on the effects of the toxic cyanobacterial strain Trichormus variabilis (heterotypic synonym Anabaena variabilis), and its toxic metabolite, cyanotoxin microcystin-LR, on Chironomus riparius larvae in a multistress environment. An environmentally relevant concentration of microcystin-LR (0.01 mg/L) caused an increase in larvae mortality in an acute toxicity test, which became greater in the presence of environmental stressors (NO3-, NH4+, PO43- and Cd2+), pointing to an additive effect of these agents. Chronic exposure of C. riparius larvae to the microcystin-LR producing strain of T. variabilis in a multistress environment led to a reduction in the larval mass and hemoglobin concentration, and it induced DNA damage in larval somatic cells. The results revealed the additive effect of microcystin-LR in combination with all three tested stressors (NO3-, NH4+, PO43-), and the deleterious effect of chronic exposure of C. riparius larvae to the microcystin-LR producing T. variabilis in a multistress environment. However, the present study further emphasizes the importance of investigating interactions between stressors and cyanotoxins, and their effect on aquatic organisms.


Assuntos
Chironomidae , Cianobactérias , Poluentes Químicos da Água , Animais , Larva , Poluentes Químicos da Água/toxicidade , Microcistinas/toxicidade , Testes de Toxicidade Aguda
4.
Environ Toxicol Chem ; 41(11): 2721-2731, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35942926

RESUMO

The fathead minnow (Pimephales promelas) fish embryo acute toxicity (FET) test was compared to the fish gill cells (RTgill-W1) in vitro assay and to the fish larvae acute toxicity test to evaluate their sensitivity for whole-effluent toxicity (WET) testing. The toxicity of 12 chemicals relevant for WET testing was compared as proof of principle. The concentrations lethal to 50% of a population (LC50) of embryos were compared to those in fish larvae and to the 50% effect concentration (EC50) in RTgill-W1 cells from previous literature. Along with traditional FET endpoints (coagulation, somite development, tail detachment, and heartbeat), cardiotoxicity was evaluated for WET applicability. Heart rate was measured at LC20 and LC50 values of six subselected chemicals (Cd, Cu, Ni, ammonia, 3,4-dichloraniline, and benzalkonium chloride). In addition, the toxicity of Cd and Ni was evaluated in RTgill-W1 cells exposed in a hypoosmotic medium to evaluate the effect that osmolarity may have on metal toxicity. A significant correlation was found between the FET and larvae LC50 values but not between the RTgill-W1 EC50 and FET LC50 values. Although sensitivity to Ni and Cd was found to increase with hypoosmotic conditions for FET and RTgill-W1 cells, a correlation was only found with removal of Ni from the analysis. Hypoosmotic conditions increased sensitivity with a significant correlation between RTgill-W1 cells and larvae. Cardiotoxicity was shown in three of the five subselected chemicals (Cd, Cu, and 3,4-dichloroaniline). Overall, both in vitro alternative models have shown good predictability of toxicity in fish in vivo for WET chemicals of interest. Environ Toxicol Chem 2022;41:2721-2731. © 2022 SETAC.


Assuntos
Amônia , Cyprinidae , Animais , Cádmio , Compostos de Benzalcônio/farmacologia , Cardiotoxicidade , Testes de Toxicidade Aguda , Linhagem Celular , Larva
5.
Arch Toxicol ; 96(11): 3033-3051, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35920856

RESUMO

Valproic acid is a frequently used antiepileptic drug and known pediatric hepatotoxic agent. In search of pharmaceuticals with increased effectiveness and reduced toxicity, analogue chemicals came into focus. So far, toxicity and teratogenicity data of drugs and metabolites have usually been collected from mammalian model systems such as mice and rats. However, in an attempt to reduce mammalian testing while maintaining the reliability of toxicity testing of new industrial chemicals and drugs, alternative test methods are being developed. To this end, the potential of the zebrafish (Danio rerio) embryo to discriminate between valproic acid and 14 analogues was investigated by exposing zebrafish embryos for 120 h post fertilization in the extended version of the fish embryo acute toxicity test (FET; OECD TG 236), and analyzing liver histology to evaluate the correlation of liver effects and the molecular structure of each compound. Although histological evaluation of zebrafish liver did not identify steatosis as the prominent adverse effect typical in human and mice, the structure-activity relationship (SAR) derived was comparable not only to human HepG2 cells, but also to available in vivo mouse and rat data. Thus, there is evidence that zebrafish embryos might serve as a tool to bridge the gap between subcellular, cell-based systems and vertebrate models.


Assuntos
Poluentes Químicos da Água , Peixe-Zebra , Animais , Anticonvulsivantes/toxicidade , Criança , Embrião não Mamífero , Humanos , Mamíferos , Camundongos , Estrutura Molecular , Preparações Farmacêuticas/metabolismo , Ratos , Reprodutibilidade dos Testes , Testes de Toxicidade Aguda/métodos , Ácido Valproico/toxicidade , Poluentes Químicos da Água/metabolismo
6.
Braz J Biol ; 84: e264320, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35946729

RESUMO

Toxicological studies are essential for developing novel medications in pharmaceutical industries including ayurvedic preparation. Hence, the present study is aimed to evaluate acute and 28-days repeated dose oral toxicity of anti-obesity polyherbal granules (PHG) in Sprague Dawley rats by OECD guidelines No 425 and 407, respectively. In an acute oral toxicity study, a single dose of 2 g/kg PHG was administered to rats and mortality, body weight, and clinical observations were noted for fourteen days. However, in the subacute oral toxicity study, the PHG was administered orally at doses of 0.3, 0.5 and 1 g/kg daily for 28 days to rats. Food intake and body weight were recorded weekly. On the 29th day, rats were sacrificed and subjected to haematological, biochemical, urine, necropsy, and histopathological analysis. In an acute oral toxicity study, no treatment-related, mortality, behavioral changes, and toxicity were found throughout fourteen days. Likewise, in the sub-acute toxicity study, no mortality and toxic effects were found in haematology, biochemical, urine, necropsy and histopathological analysis in rats for 28 days of treatment with PHG. Based on these results, the LD50 of PHG was found to be greater than 2 g/kg and the no-observed-adverse-effect level (NOAEL) of PHG for rats was found to be 0.5 g/kg/day. Thus, anti-obesity polyherbal granules showed a good safety profile in animal studies and can be considered an important agent for the clinical management of obesity.


Assuntos
Obesidade , Animais , Peso Corporal , Relação Dose-Resposta a Droga , Nível de Efeito Adverso não Observado , Obesidade/induzido quimicamente , Ratos , Ratos Sprague-Dawley , Testes de Toxicidade Aguda/métodos
7.
Artigo em Inglês | MEDLINE | ID: mdl-36012048

RESUMO

OBJECTIVE: This study was conducted to evaluate the acute and subchronic toxicity of anthraquinone. An acute toxicity test was performed in female Sprague Dawley (SD) rats, and the oral median lethal dose (LD50) of anthraquinone was estimated to be >5000 mg/kg body weight (BW). In the subchronic study, groups of 10 male and 10 female rats were dosed with anthraquinone by gavage at 0, 1.36, 5.44, 21.76, and 174.08 mg/kg BW, 7 days/week for 90 days followed by a recovery period of 28 days. No appreciable toxic-related changes were observed in the 1.36 mg/kg BW group. When the animals received 5.44 mg/kg BW or more of anthraquinone, hyaline droplet accumulation in the renal tubules was observed in both the male and female rats, and anemia was observed in the females. When the anthraquinone dose reached 174.08 mg/kg BW, mild hepatocellular hypertrophy around the central vein of the hepatic lobule and hypothyroidism were observed in the female rats. During the recovery period, changes in clinical symptoms and parameters were considerably alleviated. Based on the results of this study, the no observed adverse effect level (NOAEL) for anthraquinone in rats was set at 1.36 mg/kg BW, and the lowest observed adverse effect level (LOAEL) was 5.44 mg/kg BW.


Assuntos
Antraquinonas , Administração Oral , Animais , Antraquinonas/toxicidade , Peso Corporal , Feminino , Masculino , Nível de Efeito Adverso não Observado , Tamanho do Órgão , Ratos , Ratos Sprague-Dawley , Testes de Toxicidade Aguda , Testes de Toxicidade Subcrônica
8.
Aquat Toxicol ; 249: 106240, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35863251

RESUMO

Originally designed as a general alternative to acute fish toxicity testing (AFT), the fish embryo toxicity test (FET) has become subject to concerns with respect to neurotoxic substances. Whereas oxygen uptake in the fish embryo primarily occurs via diffusion across the skin, juvenile and adult fish rely on active ventilation of the gills. As a consequence, substances including, e.g., neurotoxicants which prevent appropriate ventilation of gills ("respiratory failure syndrome") might lead to suffocation in juvenile and adult fish, but not in skin-breathing embryos. To investigate if this respiratory failure syndrome might play a role for the higher sensitivity of juvenile and adult fish to neurotoxicants, a modified acute toxicity test using post-embryonic, early gill-breathing life-stages of zebrafish was developed with chlorpyrifos, permethrin, lindane, aldicarb, ziram and aniline as test substances. Additionally, a comparative study into bioaccumulation of lipophilic substances with logKow > 3.5 and swimbladder deflation as potential side effects of the respiratory failure syndrome was performed with 4 d old skin-breathing and 12 d old gill-breathing zebrafish. With respect to acute toxicity, post-embryonic 12 d larvae proved to be more sensitive than both embryos (FET) and adult zebrafish (AFT) to all test substances except for permethrin. Accumulation of chlorpyrifos, lindane and permethrin was 1.3- to 5-fold higher in 4 d old than in 12 d old zebrafish, suggesting that (intermediate) storage of substances in the yolk might reduce bioavailability and prevent metabolization, which could be a further reason for lower toxicity in 4 d than in 12 d old zebrafish. Whereas ziram and aniline showed no significant effect on the swimbladder, zebrafish exposed to chlorpyrifos, lindane and permethrin showed significantly deflated swimbladders in 12 d old larvae; in the case of aldicarb, there was a significant hyperinflation in 4 d old larvae. Swimbladder deflation in post-embryonic 12 d zebrafish larvae might be hypothesized as a reason for a lack of internal oxygen supplies during the respiratory failure syndrome, whereas in 4 d old embryos cholinergic hyperinflation of the swimbladder dominates over other effects. Regarding acute lethality, the study provides further evidence that the switch from transcutaneous to branchial respiration in post-embryonic zebrafish life-stages might be the reason for the higher sensitivity of juvenile and adult fish to neurotoxic substances.


Assuntos
Clorpirifos , Insuficiência Respiratória , Poluentes Químicos da Água , Ziram , Aldicarb/farmacologia , Compostos de Anilina/farmacologia , Animais , Clorpirifos/toxicidade , Embrião não Mamífero , Brânquias , Hexaclorocicloexano , Larva , Oxigênio , Permetrina/farmacologia , Respiração , Testes de Toxicidade Aguda/métodos , Poluentes Químicos da Água/toxicidade , Peixe-Zebra , Ziram/farmacologia
9.
Toxins (Basel) ; 14(7)2022 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-35878213

RESUMO

Dysphania ambrosioides (L.) Mosyakin and Clemants is a medicinal plant that has traditionally been used to cure a range of diseases. There has been no thorough investigation of the potential toxicity of this plant. The objective of this study is to assess the acute and subacute toxicity of D. ambrosioides hydroethanolic extract (DAHE), as well as it alkaloids composition, utilizing LC-MS/MS analysis. An in silico approach was applied to determine pharmacokinetic parameters and to predict the toxicity of D. ambrosioides identified alkaloids. A 14-day treatment with a single oral dose of 1-7 g/kg was carried out to investigate acute toxicity. DAHE was given orally at dosages of 5, 50, and 500 mg/kg for 15 days in the subacute toxicity investigation, and body weight and biochemical parameters were evaluated. Livers, kidneys, lungs, and heart were examined histologically. Chromatographic investigation revealed the existence of nine alkaloids, with N-formylnorgalanthamine being the most prevalent. The oral LD50 value of DAHE was found to be 5000 mg/kg in an acute toxicity study. No variations were observed with respect to food intake, water consumption, mortality, or body and organ weight in the subacute toxicity study. On the other hand, DAHE (500 mg/kg) significantly enhanced alanineaminotransferase, aspartate aminotransferase, and urea. Liver and kidney histological examinations revealed modest infiltration of hepatocyte trabeculae by inflammatory cells in the liver and slight alteration in the kidney histoarchitecture. According to our findings, DAHE exhibits low to moderate toxicity.


Assuntos
Alcaloides , Espectrometria de Massas em Tandem , Alcaloides/análise , Alcaloides/toxicidade , Cromatografia Líquida , Flores/química , Extratos Vegetais/química , Testes de Toxicidade Aguda
10.
Regul Toxicol Pharmacol ; 133: 105217, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35792246

RESUMO

The toxicological potential of the ethanolic extract from Gomphrena celosioides (EEGC), a medicinal plant used as a natural analgesic, was investigated in acute and subacute toxicity models in rodents. For the acute toxicity test, 2000 mg/kg of EEGC was administered orally to male and female Wistar rats, while Swiss mice received 75, 150 or 300 mg/kg of EEGC for the subacute toxicity test. Animals treated with an only dose of 2000 mg/kg EEGC showed no clinical signs of toxicity, indicating that the LD50 is higher than this dose. The repeated treatment with EEGC did not cause adverse clinical signs, or lesions in target tissues. According to the Globally Harmonized System of classification, the EEGC dosages can be in Category 5 which is the least toxic or non-toxic one.


Assuntos
Amaranthaceae , Roedores , Animais , Etanol , Feminino , Masculino , Camundongos , Componentes Aéreos da Planta , Extratos Vegetais/uso terapêutico , Extratos Vegetais/toxicidade , Ratos , Ratos Wistar , Testes de Toxicidade Aguda , Testes de Toxicidade Subaguda
11.
Regul Toxicol Pharmacol ; 133: 105214, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35781033

RESUMO

Rhuleave-K™ is a proprietary combination of Curcuma longa extract, Boswellia serrata extract and black sesame seed oil. Acute toxicity was evaluated as per OECD guidelines 423. Rhuleave-K™ was fed at 2000 mg/kg to overnight fasted female rats. Clinical signs of abnormality and mortality was observed daily for 14 days. Sub-chronic toxicity was studied by feeding Rhuleave-K™ at 100, 500 and 1000 mg/kg/day to rats as per OECD guidelines 408. After 90 days feeding, hematological and biochemical parameters were analyzed. Histopathology of all the major organs was also studied. In the acute toxicity study, there was no clinical sign of toxicity in any of the rats at maximum dose of 2000 mg/kg. The LD50 was computed as >2000 mg/kg in rats. The repeated dosing of Rhuleave-K™ at the maximum dose level of 1000 mg/kg for 90 days did not induce any observable toxic effects in rats, when compared to its corresponding control. The hematology and biochemistry profiles of treated rats were similar to control animals and difference was non-significant (p > 0.05). The histopathology of major organs of all the control and treated animals was normal. In this study the NOAEL for Rhuleave-K™ was calculated as 1000 mg/kg daily in rats.


Assuntos
Dor , Extratos Vegetais , Animais , Feminino , Nível de Efeito Adverso não Observado , Dor/tratamento farmacológico , Ratos , Testes de Toxicidade Aguda
12.
Environ Toxicol Chem ; 41(9): 2305-2317, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35735071

RESUMO

While zebrafish (Danio rerio) have been accepted worldwide for evaluating chemical hazards to aquatic vertebrates, and in some countries it is mandated to generate fish toxicity data using native species, such as Chinese rare minnow (Gobiocypris rarus) in China. This represents an additional regulatory constraint that may cause redundant tests, additional animal uses, and higher costs. Previous studies showed that juvenile G. rarus was more sensitive than zebrafish juveniles and embryos to metals. To better understand the sensitivity of G. rarus to organic chemicals, we selected 29 fragrance ingredients belonging to various chemical classes and with differing physicochemical properties, for which good quality zebrafish acute toxicity data were available and tested them with juvenile G. rarus and embryo D. rerio using the Organisation of Economic Co-operation and Development test guidelines. Chemical toxicity distribution (CTD) and chemical ratio distribution (CRD) models were established to systematically compare the sensitivity between juveniles of G. rarus and D. rerio, as well as between D. rerio embryos and juveniles. The results of the CTD models showed that for tested chemicals, the sensitivity of juvenile G. rarus was similar to that of D. rerio juveniles and embryos. The CRD comparisons revealed that juvenile G. rarus was slightly less sensitive by a factor of ~2 than juvenile D. rerio to ingredients belonging to Verhaar class 3 and Ecological Structure Activity Relationship ester class, while comparable to other chemicals. These comparative experiments demonstrated that fish toxicity data with G. rarus can be submitted for use in chemical registrations outside China, which would avoid repeating animal tests using D. rerio. Meanwhile, the similar sensitivity of zebrafish juveniles and embryos to fragrance ingredients confirmed the suitability of replacing juveniles by zebrafish embryos. Environ Toxicol Chem 2022;41:2305-2317. © 2022 SETAC.


Assuntos
Cyprinidae , Poluentes Químicos da Água , Animais , China , Embrião não Mamífero , Odorantes , Testes de Toxicidade Aguda , Poluentes Químicos da Água/toxicidade , Peixe-Zebra
13.
Environ Toxicol Chem ; 41(9): 2095-2106, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35665535

RESUMO

Mathematical models are presented for the acute median lethal concentrations of major geochemical ions (Na+ , K+ , Ca2+ , Mg2+ , Cl- , SO4 2- , HCO3 - /CO3 2- ) to fathead minnows (Pimephales promelas), based on an extensive series of experiments presented in a companion article. Toxicity relationships across different dilution waters, individual salts, and salt mixtures suggest six independent mechanisms of toxicity to consider in modeling efforts, including Mg/Ca-specific toxicity, osmolarity-related toxicity, SO4 -specific toxicity, K-specific toxicity, effects of high pH/alkalinity, and a multiple ion-related toxicity at low Ca distinct from the other mechanisms. Models are evaluated using chemical activity-based exposure metrics pertinent to each mechanism, but concentration-based alternative models that are simpler to apply are also addressed. These models are compared to those previously provided for Ceriodaphnia dubia, and various issues regarding their application to risk assessments are discussed. Environ Toxicol Chem 2022;41:2095-2106. © 2022 SETAC. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.


Assuntos
Cladóceros , Cyprinidae , Poluentes Químicos da Água , Animais , Humanos , Íons , Testes de Toxicidade Aguda , Poluentes Químicos da Água/química
14.
Toxicol In Vitro ; 83: 105408, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35660067

RESUMO

Acute oral toxicity is primarily determined using animal testing, as stated in the Organization for Economic Cooperation and Development (OECD) Test Guideline (TG) 420, 423, and 425. Currently, regarding animal welfare, few alternatives to animal testing such as in vitro approaches have been evaluated. Therefore, in this preliminary study examining a new method to determine acute oral toxicity, we investigated whether UN Globally Harmonized System all categories can be predicted using the Hansen solubility parameter (HSP). In particular, Hansen spheres were produced based on oral toxicity information of the test substances and their HSP values, and the respective parameters were identified. A comparison of these potential parameters with the HSP value of each test substance showed an accuracy of 84.1% (53/63), 10.0% (3/30) false negatives, and 21.2% (7/33) false positives. By comparing the HSP of the resulting potential parameters with a test substance, it is possible to predict acute oral toxicity with high accuracy.


Assuntos
Organização para a Cooperação e Desenvolvimento Econômico , Animais , Solubilidade , Testes de Toxicidade Aguda/métodos
15.
Environ Toxicol Chem ; 41(9): 2259-2272, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35703088

RESUMO

Cationic polymers are considered by the scientific and regulatory communities as a group of greater interest amongst the polymers in commerce. As a category, relatively little hazard information is available in the public literature. Very few examples exist of published, high-quality polymer characterization and quantification of exposure. In the present study we describe a series of fish embryo toxicity (FET) and fish gill cytotoxicity assays used to establish a baseline understanding of several representative polyquaternium categories (PQ-6, PQ-10, PQ-16) in animal alternative models, accompanied by high-quality analytical characterization. Materials were chosen to encompass a range of molecular weights and charge densities to determine the influence of test material characteristics on toxicity. Both chorionated and dechorionated FET assays were generally similar to published acute fish toxicity data. Toxicity was correlated with cationic polymer charge density, and not with molecular weight, and was a combination of physical effects and likely toxicity at the site of action. Toxicity could be ameliorated by humic acid in a dose-dependent manner. Fish gill cytotoxicity results were orders of magnitude less sensitive than FET test responses. Environ Toxicol Chem 2022;41:2259-2272. © 2022 SETAC.


Assuntos
Embrião não Mamífero , Brânquias , Animais , Ecotoxicologia , Peixes , Polímeros/toxicidade , Testes de Toxicidade Aguda/métodos
16.
Harmful Algae ; 115: 102232, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35623688

RESUMO

Cyanobacteria can produce highly potent cyanotoxins, however, limited information is provided about their toxicity mechanisms in exposed aquatic invertebrates at the molecular level. In the present study, the effects of cyanobacterial strains from the genus Nostoc (Nostoc Z1 and Nostoc 2S3B) in Daphnia magna after waterborne exposure were investigated. Examined endpoints included immobilization (survival) in acute toxicity tests and selected gene expression changes (cyp314, cyp360A8, gst, p-gp, vtg) analyzed by the quantitative real-time polymerase chain reaction (RT-PCR). In addition, enzyme-linked immunosorbent assay (ELISA) was performed to determine whether the observed changes could be due to the presence of microcystins, the most widespread group of cyanotoxins. The results of acute toxicity tests have shown only minor changes in survival rates, which have not exceeded 20% after 48 h of exposure to either strain. On the other hand, significant changes were recorded in molecular responses of Daphnia to tested strains. Treatment with the aquatic strain Nostoc Z1 altered the expression levels of all analyzed genes. Both strains caused a significant p-glycoprotein (p-gp) induction at 75 µg ml-1 which suggests the involvement of p-gp mediated multixenobiotic resistance mechanism (MXR) in facilitating excretion of toxic cyanobacterial compounds in daphnids. Additionally, these strains caused an increase in the expression levels of cyp360A8, indicating that genes related to detoxification processes could be sensitive indicators of cyanobacterial toxicity. Statistically significant induction of cyp314, as well as increases in expression of gst and vtg, were observed only after exposure to Nostoc Z1. This study indicates the potential of certain cyanobacterial metabolites to modify the expression of toxicant responsive genes involved in phase I and phase III of the xenobiotic metabolism, as well as possible interference with growth and reproduction in D. magna. Low microcystin concentrations found in both samples suggest that these cyanotoxins were not responsible for the detected toxic effects.


Assuntos
Nostoc , Animais , Toxinas de Cianobactérias , Daphnia , Expressão Gênica , Nostoc/genética , Reação em Cadeia da Polimerase em Tempo Real , Testes de Toxicidade Aguda
17.
Appl Biochem Biotechnol ; 194(9): 3890-3900, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35556209

RESUMO

Cadmium chloride is a metal salt used in industries in a large scale. Trichogaster (Colisa) fasciata (common name banded gourami) is an air-breathing fresh water fish with both nutritional and ornamental values. In this present study, as per EPA guidelines, acute toxicity bioassay was performed in a 96-h static test method in four replicates, each replicate having one control and five concentrations (25, 50, 75, 100 and 125 mg/L, respectively) of the metal salt. A total of 192 fish was used in the study in four series with each replicate containing 8 fish per concentration. The water temperature was maintained at 20-22℃ during the study. The data observed were analysed statistically on the basis of Finney's Probit Analysis method using SPSS software. The estimated 96-h LC50 value of cadmium chloride for the fish was 49.5 mg/L.


Assuntos
Perciformes , Poluentes Químicos da Água , Animais , Bioensaio , Cádmio/toxicidade , Cloreto de Cádmio/toxicidade , Peixes , Água Doce , Dose Letal Mediana , Testes de Toxicidade Aguda
18.
Regul Toxicol Pharmacol ; 133: 105188, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35636684

RESUMO

MPTA is a novel extract product derived from Macleaya cordata (Willd.) R. Br., which has good anti-inflammatory and antioxidant activity. The aim of this study was to investigate the acute oral toxicity and 90-day sub-chronic oral toxicity of MPTA. In the acute toxicity study, 50 SD rats of both sexes were randomly divided into 5 groups and dosed in a gradient from 197.53 mg/kg to 1000.00 mg/kg bw. Toxic effects were observed up to 14 days and LD50 was calculated. In a subchronic toxicity test, male and female SD rats were orally dosed repeatedly with 96.40, 19.28, 3.86 mg/kg bw of MPTA for 90 days. In addition, a control group was set up in the subchronic study. The acute toxicity test showed that the oral LD50 of MPTA was 481.99 mg/kg with a 95% confidence interval of 404.24-574.70 mg/kg. MPTA did not appear to induce toxic effects in the longer term in terms of food and water consumption, weight gain, haematological and clinical biochemical parameters and pathological examination. The first data on the potential toxicity of MPTA was provided to highlight the safety of short-term to longer-term oral administration of MPTA, and the experimental results yield and establish a NOEAL of 96.40 mg/kg/d for MPTA.


Assuntos
Extratos Vegetais , Compostos de Amônio Quaternário , Administração Oral , Animais , Feminino , Dose Letal Mediana , Masculino , Extratos Vegetais/toxicidade , Compostos de Amônio Quaternário/toxicidade , Ratos , Ratos Sprague-Dawley , Testes de Toxicidade Aguda , Testes de Toxicidade Subcrônica
19.
Regul Toxicol Pharmacol ; 132: 105191, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35613671

RESUMO

Pinus halepensis Mill. seed (Pinaceae), popularly known as 'Zgougou', is widely consumed in the Mediterranean countries and used traditionally in the treatment of some diseases such as bronchitis, rheumatism, infection, and inflammation. The present study aimed to evaluate the oral safety of cold pressed oil of Pinus halepensis Mill. seeds (COPHS) by acute and 28-day repeated dose toxicities studies in Wistar mice and rats, respectively. In the acute toxicity study, oral administration of COPHS to mice did not provoke mortality or any toxic signs at doses up to 5000 mg/kg bw. After administration of COPHS at doses of 250, 500, and 1000 mg/kg bw/day for 28 days, no abnormal changes were observed in body weight, water intake, food consumption, organ weight, blood haematological, serum biochemistry parameters, and histology profile. Furthermore, there was no animal death or any symptom of toxicity in any group during sub-acute toxicity test period. Our findings demonstrate that COPHS is relatively non-toxic and has a large safety margin (>5000 mg/kg). The results of the present research provide basic reference data for food consumption and for future in vivo screening of biological and pharmacological properties of cold pressed oil of Pinus halepensis Mill. seeds.


Assuntos
Pinus , Animais , Camundongos , Pinus/química , Extratos Vegetais , Óleos Vegetais/toxicidade , Ratos , Ratos Wistar , Sementes/química , Testes de Toxicidade Aguda
20.
Bol. latinoam. Caribe plantas med. aromát ; 21(3): 323-342, mayo 2022. tab, ilus
Artigo em Inglês | LILACS | ID: biblio-1396881

RESUMO

Copaifera spp. essential oil (EOC) was extracted by hydrodistillation of Copaifera oleoresin (COR). The EOC was characterized by GC/MS and a novel EOC-loaded nanoemulsion was developed to enhance the EOC solubility and to evaluate its utility as antinflammatory. EOC contain 14 volatile compounds (including ß-caryophyllene: 51.52%) having a required HLB of 11. The Surfactant: EOC: Water ratio of 13:15:75 (%, w:w:w) produced the optimal formulation (particle size: 94.47 nm). The EOC-loaded nanoemulsion presented a pseudoplastic/thixotropic behavior with excellent shelf stability for 6 months. The anti-inflammatory effect of the nanoemulsion was more potent than that of the EOC, and statistically equal to diclofenac (50 mg/kg). The EOC-loaded nanoemulsion showed no oral acute toxicity (in mice) at 2000 mg/kg; hence, it is considered a nontoxic product. The development of the EOC-loaded nanoemulsion added value to both the COR and the EOC by providinga suitable formulation that could be used as an anti-inflammatory product.


El aceite esencial (EOC) fue extraído por hidrodestilación de oleoresina de Copaifera spp. El EOC fue caracterizado químicamente por GC/MS. Se formuló una nanoemulsión con EOC para mejorar la solubilidad del EOC y evaluar su utilidad como antiinflamatorio. El EOC contiene 14 compuestos volátiles (incluido el ß-cariofileno: 51,52%) con un HLB requerido de 11. La relación Tensioactivo: EOC: Agua de 13:15:75 (%, p:p:p) produjo la formulación óptima (tamaño de partícula: 94,47 nm).. La nanoemulsión cargada con EOC presentó un comportamiento pseudoplástico/tixotrópico con una excelente estabilidad en almacenamiento durante 6 meses. El efecto antiinflamatorio de la nanoemulsión fue más potente que el del EOC y estadísticamente igual al diclofenaco (50 mg/kg). La nanoemulsión cargada con COE no mostró toxicidad aguda oral (en ratones) a 2000 mg/kg; por lo tanto, se considera un producto no tóxico. El desarrollo de la nanoemulsión cargada con EOC agregó valor tanto al COR como al EOC al proporcionar una formulación adecuada que podría usarse como un producto antiinflamatorio.


Assuntos
Animais , Camundongos , Óleos Voláteis/farmacologia , Fabaceae/química , Anti-Inflamatórios/farmacologia , Reologia , Tensoativos , Temperatura , Óleos Voláteis/química , Testes de Toxicidade Aguda , Emulsões/farmacologia , Nanopartículas , Sesquiterpenos Policíclicos/análise , Concentração de Íons de Hidrogênio , Cromatografia Gasosa-Espectrometria de Massas
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