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1.
Toxicol Appl Pharmacol ; 475: 116628, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37506978

RESUMO

CD19 Chimeric antigen receptor T (CAR-T) cell therapy has shown a promising response rate for relapsed/refractory B-cell malignancies. However, serious side effects such as cytokine release syndrome and immune effector cell-associated neurotoxicity syndrome arose in early case reports. Though several preclinical and clinical studies of CAR-T cell therapy have been reported, there is a lack of toxicological assessments. This study was carried out as a preclinical assessment of CD19 CAR-T cell therapy, including the anti-leukemic efficacy, kinetics in peripheral blood, and 4-week single-dose toxicity evaluation in leukemia xenograft mice. Leukemia xenograft mice model was established by injecting 1.0 × 105 cells/mouse of luciferase-labeled human B cell acute lymphoblastic leukemia (B-ALL) cell line via the tail vein, and after 3 days, 2.0 or 4.0 × 106 cells/mouse of CD19 CAR-T cells were injected intravenously. CD19 CAR-T cells showed significant anti-leukemic efficacy, showing inhibition of tumor progression in the bioluminescence-based in-vivo imaging system. In the kinetics study using qPCR, CAR-T cells peaked in peripheral blood on day 60 in males and day 30 in females. In a 4-week single-dose toxicity study, CD19 CAR-T cell injected groups showed no mortality and toxicological signs, or changes in body weight, food/water consumption, hematology, clinical chemistry, organ weights, and histopathology compared to control groups. These results suggested that 4.0 × 106 cells/mouse of CD19 CAR-T cells were effective in B-ALL xenograft mice without serious side effects, so the no-observed adverse effect level (NOAEL) was estimated to be higher than 4.0 × 106 cells/mouse, under the condition examined in the current study.


Assuntos
Linfoma de Burkitt , Leucemia , Receptores de Antígenos Quiméricos , Masculino , Feminino , Humanos , Camundongos , Animais , Receptores de Antígenos Quiméricos/genética , Receptores de Antígenos Quiméricos/uso terapêutico , Xenoenxertos , Cinética , Linfoma de Burkitt/tratamento farmacológico , Leucemia/tratamento farmacológico , Antígenos CD19 , Terapia Baseada em Transplante de Células e Tecidos
2.
Cell Biol Toxicol ; 39(1): 165-182, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-34283317

RESUMO

Gap junctional intercellular communication (GJIC) is considered a key biological mechanism to maintain homeostasis in cell differentiation and growth. In addition, as another major signaling pathway associated with cell proliferation and differentiation, Wnt/ß-catenin signaling appears to trigger several cellular responses against injury. The purpose of the present study was to investigate the effects of a known toxic agent, benzo[a]pyrene (BaP), on the regulation and interaction between GJIC and Wnt/ß-catenin signaling. BaP treatment resulted in GJIC inhibition and decreases the major GJIC protein connexin 43 (Cx43) in WB-F344 rat liver epithelial cells. We also found BaP-mediated downregulation of Wnt/ß-catenin signaling related to the PI3K-Akt pathway. To identify the relationship between GJIC and Wnt/ß-catenin signaling, we treated WB-F344 cells with the Wnt agonist CHIR99021 and found that it inhibited GJIC while causing a significant reduction in Cx43 expression at both the mRNA and protein levels, through the repression of promoter activity. This Wnt agonist-mediated GJIC inhibition was confirmed using a small interfering RNA directed against the Wnt antagonist Dact2, indicating that Wnt/ß-catenin signaling negatively regulates GJIC. Despite the inverse correlation between Wnt/ß-catenin signaling and Cx43 promoter activation as indicated by downregulation of ß-catenin nuclear translocation and upregulation of Cx43 promoter activation involving HNF3ß, BaP treatment decreased the Cx43 protein expression, which was associated with protein degradation, possibly through protein kinase C activation. In conclusion, our results revealed the mechanism of BaP-induced inhibition of GJIC and Wnt/ß-catenin signaling. More importantly, linking Wnt/ß-catenin signaling to Cx protein expression will have profound implications in understanding the relationships among different major signaling pathways associated with cell proliferation and differentiation in toxicity.


Assuntos
Conexina 43 , beta Catenina , Ratos , Animais , Conexina 43/metabolismo , Conexina 43/farmacologia , Ratos Endogâmicos F344 , beta Catenina/metabolismo , Via de Sinalização Wnt , Fosfatidilinositol 3-Quinases/metabolismo , Junções Comunicantes/metabolismo , Pirenos/metabolismo , Pirenos/farmacologia , Proteínas Nucleares/metabolismo
3.
Am J Primatol ; 85(9): e23532, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37357545

RESUMO

The common marmoset (Callithrix jacchus) is considered an ideal species for developing genetically modified nonhuman primates (NHP) models of human disease, particularly eye disease. They have been proposed as a suitable bridge between rodents and other NHP models due to their similar ophthalmological features to humans. Prenatal ultrasonography is an accurate and reliable diagnostic tool for monitoring fetal development and congenital malformation. We monitored fetal eye growth and development using noninvasive ultrasonography in 40 heads of clinically normal fetuses during pregnancy to establish the criteria for studying congenital eye anomalies in marmosets. The coronal, sagittal, and transverse planes were useful to identify the facial structures for any associated abnormalities. For orbital measurements, biorbital distance (BOD), ocular diameter (OD), interorbital distance (IOD), and total axial length (TAL) were measured in the transverse plane and carefully identified for intraorbital structures. As a result, high correlations were observed between delivery-based gestational age (GA) and biparietal diameter (BPD), BOD, OD, and TAL. The correlation assessments based on BOD provide more reliable results for monitoring eye growth and development in normal marmosets than any other parameters since BOD has the highest correlation coefficient according to both delivery-based GA and BPD among ocular measurements. In conclusion, orbital measurements by prenatal ultrasonography provide reliable indicators of marmoset eye growth, and it could offer early diagnostic criteria to facilitate the development of eye disease models and novel therapies such as genome editing technologies in marmosets.

4.
J Med Primatol ; 51(3): 195-198, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35266161

RESUMO

A pregnant common marmoset (Callithrix jacchus) showed tachypnea, hypothermia, and anorexia at close to the expected delivery date. Severe anemia and thrombocytopenia, schistocytes, and high levels of LDH and D-dimer were observed. Three days after the onset of clinical signs, a cesarean section was conducted due to stillbirth. Marmoset immediately recovered after surgery, and the abnormal CBC and blood chemistry parameters before surgery returned to the normal ranges. Diagnosis of pregnancy-associated thrombotic microangiopathy was made because removal of infant and placenta is curative. To the best of our knowledge, this is the first case report of thrombotic microangiopathy in a marmoset with preeclampsia.


Assuntos
Pré-Eclâmpsia , Microangiopatias Trombóticas , Animais , Callithrix , Callitrichinae , Cesárea/efeitos adversos , Cesárea/veterinária , Feminino , Pré-Eclâmpsia/diagnóstico , Gravidez , Microangiopatias Trombóticas/diagnóstico , Microangiopatias Trombóticas/etiologia , Microangiopatias Trombóticas/terapia
5.
J Med Primatol ; 51(4): 253-255, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35352840

RESUMO

A female common marmoset (Callithrix jachhus) suffered from weight loss exhibited tachypnea after anesthesia. We diagnosed marmoset duodenal dilation syndrome (MDDS) and aspiration pneumonia after post-anesthesia vomiting secondary to MDDS. If MDDS is suspected due to clinical symptoms such as weight loss, bloating, or vomiting, careful anesthesia and treatment of vomiting will be important to prevent aspiration pneumonia.


Assuntos
Callithrix , Pneumonia Aspirativa , Animais , Dilatação , Feminino , Pneumonia Aspirativa/etiologia , Pneumonia Aspirativa/veterinária , Vômito , Redução de Peso
6.
J Appl Toxicol ; 42(11): 1832-1842, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35792566

RESUMO

Many defined approaches (DAs) for skin sensitization assessment based on the adverse outcome pathway (AOP) have been developed to replace animal testing because the European Union has banned animal testing for cosmetic ingredients. Several DAs have demonstrated that machine learning models are beneficial. In this study, we have developed an ensemble prediction model utilizing the graph convolutional network (GCN) and machine learning approach to assess skin sensitization. The model integrates in silico parameters and data from alternatives to animal testing of well-defined AOP to improve DA predictivity. Multiple ensemble models were created using the probability produced by the GCN with six physicochemical properties, direct peptide reactivity assay, KeratinoSens™, and human cell line activation test (h-CLAT), using a multilayer perceptron approach. Models were evaluated by predicting the testing set's human hazard class and three potency classes (strong, weak, and non-sensitizer). When the GCN feature was used, 11 models out of 16 candidates showed the same or improved accuracy in the testing set. The ensemble model with the feature set of GCN, KeratinoSens™, and h-CLAT produced the best results with an accuracy of 88% for assessing human hazards. The best three-class potency model was created with the feature set of GCN and all three assays, resulting in 64% accuracy. These results from the ensemble approach indicate that the addition of the GCN feature could provide an improved predictivity of skin sensitization hazard and potency assessment.


Assuntos
Cosméticos , Dermatite Alérgica de Contato , Alternativas aos Testes com Animais/métodos , Animais , Dermatite Alérgica de Contato/etiologia , Humanos , Aprendizado de Máquina , Pele
7.
Drug Chem Toxicol ; 44(3): 268-276, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-31215257

RESUMO

Taurodeoxycholate (TDCA) inhibits various inflammatory responses suggesting potential clinical application. However, the toxicity of TDCA has not been evaluated in detail in vivo. We investigated the acute toxicity and 4-week repeated-dose toxicity of TDCA following intravenous infusion under Good Laboratory Practice regulations. In the sighting study of acute toxicity, one of two rats (one male and one female) treated with 300 mg/kg TDCA died with hepatotoxicity, suggesting that the approximate 50% lethal dose of TDCA is 300 mg/kg. Edema and discoloration were observed at the injection sites of tails when rats were infused with 150 mg/kg or higher amount of TDCA once. In 4-week repeated-dose toxicity study, no treatment-related mortality or systemic changes in hematology and serum biochemistry, organ weights, gross pathology, or histopathology were observed. However, the tail injection site showed redness, discharge, hardening, and crust formation along with histopathological changes such as ulceration, edema, fibrosis, and thrombosis when rats were infused with 20 mg/kg TDCA. Taken together, TDCA induced no systemic toxicity or macroscopic lesions at the injection site at a dose of 10 mg/kg/day, which is 33 times higher than the median effective dose observed in a mouse sepsis model. These findings suggest that TDCA might have a favorable therapeutic index in clinical applications.


Assuntos
Colagogos e Coleréticos/toxicidade , Ácido Taurodesoxicólico/toxicidade , Animais , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Colagogos e Coleréticos/administração & dosagem , Relação Dose-Resposta a Droga , Edema/induzido quimicamente , Feminino , Infusões Intravenosas , Dose Letal Mediana , Masculino , Ratos , Ratos Sprague-Dawley , Ácido Taurodesoxicólico/administração & dosagem , Testes de Toxicidade Aguda , Testes de Toxicidade Subaguda
8.
Drug Chem Toxicol ; 44(2): 161-169, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31215246

RESUMO

Sodium taurodeoxycholate (TDCA) has been investigated for various inflammatory disorders such as sepsis. We recently evaluated nonclinical safety profile of TDCA using rats infused intravenously. As a series of preclinical safety investigations, we further conducted toxicity studies with TDCA delivered to dogs via intravenous administration under Good Laboratory Practice regulation in this study. In dose range-finding study (dose escalation study), dogs given with TDCA at a dose of 150 mg/kg showed marked changes in clinical signs, hematology, and serum biochemistry. And biochemical markers of liver damage and local skin lesions were observed following intravenous infusion of 100 mg/kg TDCA, suggesting that 100 mg/kg was chosen as the highest dose of TDCA for 4-week repeated-dose toxicity study using dogs. Despite no treatment-related significant changes in body weight, food consumption, ophthalmoscopy, and urinalysis, skin lesions were observed at the injection site of animals administered with higher than 50 mg/kg of TDCA along with biochemical and histopathological changes associated with liver injury. However, most of off-target effects were found to be reversible since these were recovered after stopping TDCA infusion. These findings indicate that the no-observed-adverse-effect-level (NOAEL) for TDCA in dogs was considered to be 5 mg/kg/d. Taken together, our results provide important toxicological profiles regarding the safe dose of TDCA for drug development or clinical application.


Assuntos
Anti-Inflamatórios/toxicidade , Ácido Taurodesoxicólico/toxicidade , Animais , Anti-Inflamatórios/administração & dosagem , Cães , Relação Dose-Resposta a Droga , Feminino , Masculino , Nível de Efeito Adverso não Observado , Ácido Taurodesoxicólico/administração & dosagem , Testes de Toxicidade Aguda , Testes de Toxicidade Subaguda
9.
Int J Mol Sci ; 22(16)2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34445302

RESUMO

With the intent to achieve the best modalities for myocardial cell therapy, different cell types are being evaluated as potent sources for differentiation into cardiomyocytes. Embryonic stem cells and induced pluripotent stem cells have great potential for future progress in the treatment of myocardial diseases. We reviewed aspects of epigenetic mechanisms that play a role in the differentiation of these cells into cardiomyocytes. Cardiomyocytes proliferate during fetal life, and after birth, they undergo permanent terminal differentiation. Upregulation of cardiac-specific genes in adults induces hypertrophy due to terminal differentiation. The repression or expression of these genes is controlled by chromatin structural and epigenetic changes. However, few studies have reviewed and analyzed the epigenetic aspects of the differentiation of embryonic stem cells and induced pluripotent stem cells into cardiac lineage cells. In this review, we focus on the current knowledge of epigenetic regulation of cardiomyocyte proliferation and differentiation from embryonic and induced pluripotent stem cells through histone modification and microRNAs, the maintenance of pluripotency, and its alteration during cardiac lineage differentiation.


Assuntos
Diferenciação Celular/genética , Epigênese Genética/fisiologia , Miócitos Cardíacos/fisiologia , Animais , Terapia Baseada em Transplante de Células e Tecidos/métodos , Células Cultivadas , Células-Tronco Embrionárias/fisiologia , Humanos , Células-Tronco Pluripotentes Induzidas/fisiologia , Medicina Regenerativa/métodos , Engenharia Tecidual/métodos
10.
Regul Toxicol Pharmacol ; 116: 104757, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32758521

RESUMO

In vivo animal studies are required by regulatory agencies to investigate drug safety before clinical trials. In this review, we summarize the process of selecting a relevant non-rodent species for preclinical studies. The dog is the primary, default non-rodent used in toxicology studies with multiple scientific advantages, including adequate background data and availability. Rabbit has many regulatory advantages as the first non-rodent for the evaluation of reproductive and developmental as well as local toxicity. Recently, minipigs have increasingly replaced dogs and rabbits in toxicology studies due to ethical and scientific advantages including similarity to humans and breeding habits. When these species are not relevant, nonhuman primates (NHPs) can be used as the available animal models, especially in toxicology studies investigating biotherapeutics. Particularly, based on the phylogenetic relationships, the use of New-World marmosets can be considered before Old-World monkeys, especially cynomolgus with robust historical data. Importantly, the use of NHPs should be justified in terms of scientific benefits considering target affinity, expression pattern, and pharmacological cross-reactivity. Strict standards are required for the use of animals. Therefore, this review is helpful for the selection of appropriate non-rodent in regulatory toxicology studies by providing sufficient regulatory, ethical, and scientific data for each species.


Assuntos
Modelos Animais , Toxicologia/métodos , Animais , Projetos de Pesquisa , Toxicologia/ética
11.
J Nanosci Nanotechnol ; 19(3): 1729-1733, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30469255

RESUMO

During the fabrication processes for single-wall carbon nanotube thin-film transistors (SWCNT-TFTs), the impurities of organic residues such as photoresist and developer can be induced, which affects the charge transport. As a result, solution-processed SWCNT-TFTs exhibit poor and non-uniform device performance regardless of the intrinsic electrical characteristics. Here, we demonstrate a patterning technique using a selective surface treatment with solution-processed hydrophobic fluorocarbon copolymer in SWCNT-TFTs. By using the difference of wettability in a selective area, a channel region in SWCNT-TFTs can be patterned without the conventional photolithography and etching process. Furthermore, the optimized surface treatment results in denser random networks of SWCNTs in the channel patterned by such technique, compared to the dropcasted SWCNT. The statistical results of the key device metrics such as mobility and threshold voltage extracted from 30 SWCNT-TFTs conclusively prove the improved device performance of SWCNT-TFTs fabricated by such pattering technique. We believe that this work can provide a promising route to stimulate the process innovation of fabrication for high performance solution-processed electronics based on SWCNT random networks.

12.
J Nanosci Nanotechnol ; 19(3): 1759-1763, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30469261

RESUMO

There have been constant attempts as regards high-performance thin-film transistors (TFTs) by improving the charge injection between the source/drain electrode (S/D) and the channel. In this paper, we investigate the effect of the electric contact on the device performance of single-wall carbon nanotube (SWCNT) TFTs employing the suitable work function material. In order to realize the electric contacts for the dominant hole injection between the S/D and the SWCNT active channel, a high work function material of molybdenum trioxide (MoOx) fabricated by an optimized process are utilized. The contact resistance is extracted by plotting the width-normalized resistance of SWCNTTFT with Pd and MoOx contacts as a function of channel length. We also demonstrate low-voltage operating SWCNT TFTs on flexible polyimide substrates with the reduced electric contacts. Without a buffer film which has been widely used to improve the device performance of TFT on a flexible substrate, high-performance low-voltage operating SWCNT-TFTs were achieved.

13.
Int J Mol Sci ; 20(5)2019 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-30845640

RESUMO

The in vitro maturation of oocytes is frequently used as an assisted reproductive technique (ART), and has been successfully established in humans and rodents. To overcome the limitations of ART, novel procedures for the in vitro maturation of early follicles are emerging. During the follicle isolation procedure, the unintended rupture of each follicle leads to a release of extra oocytes. Such oocytes, which are obtained during follicle isolation from marmosets, can be used for early maturation studies. Marmoset (Callithrix jacchus), which is classified as a new-world monkey, is a novel model that has been employed in reproductive biomedical research, as its reproductive physiology is similar to that of humans in several aspects. The ovaries of female marmosets were collected, and the excess oocytes present during follicle isolation were retrieved without pre-gonadotropin induction. Each oocyte was matured in vitro for 48 h in the presence of various concentrations of human chorionic gonadotropin (hCG) and epidermal growth factor (EGF), and the maturity of oocytes and optimal maturation conditions were evaluated. Each oocyte was individually reverse-transcribed, and the expression of mRNAs and microRNAs (miRs) were analyzed. Concentrations of hCG significantly affected the maturation rate of oocytes [the number of metaphase II (MII) oocytes]. The expression of BMP15 and ZP1 was highest when the oocytes were matured using 100 IU/L of hCG without pre-treatment with gonadotropins, and that of Cja-mir-27a was highest when cultured with follicle stimulating hormone. These results suggest that these up-regulated miRs affect the maturation of oocytes. Interactions with other protein networks were analyzed, and a strong association of BMP15 and ZP1 with sperm binding receptor (ACR), anti-Müllerian hormone (AMH), and AMH receptor was demonstrated, which is related to the proliferation of granulosa cells. Collectively, on the basis of these results, the authors propose optimal maturation conditions of excess oocytes of marmoset without in vivo gonadotropin treatment, and demonstrated the roles of miRs in early oocyte maturation at the single-cell level in marmosets.


Assuntos
Gonadotropina Coriônica/farmacologia , Fator de Crescimento Epidérmico/farmacologia , Perfilação da Expressão Gênica/métodos , Oócitos/efeitos dos fármacos , Animais , Proteína Morfogenética Óssea 15/genética , Callithrix , Feminino , Fertilização in vitro , Hormônio Foliculoestimulante , Perfilação da Expressão Gênica/veterinária , Humanos , Técnicas de Maturação in Vitro de Oócitos , MicroRNAs/genética , Modelos Animais , Oócitos/metabolismo , Oogênese , Glicoproteínas da Zona Pelúcida/genética
14.
J Nanosci Nanotechnol ; 18(9): 6562-6564, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-29677834

RESUMO

In this paper, we demonstrate the highly sensitive carbon nanotube (CNT) sensors for the detection of sub-ppm nitric oxide (NO) gas operating at room temperature. Such achievement can be realized by functionalizing CNT thin films with amine-based polymers through a solution-process technology at low temperature. In addition to high sensitivity, functionalized CNT sensors exhibit high selectivity towards NO gas, which is an effective and practical factor for health-care monitoring nano-electronics. We also investigated the effect of a post-cleaning treatment on the sensing performance of functionalized CNT thin films for sub-ppm NO gas sensors. We believe that this work can open-up new routes to realize high performance human-interactive electronics for respiratory diseases detection in exhaled air.

15.
Regul Toxicol Pharmacol ; 95: 115-123, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29501463

RESUMO

Cinnamomum cassia has been widely used as a natural product to treat diseases in Asia due to its diverse pharmacological functions including anti-inflammatory, anti-oxidant, anti-microbial, anti-diabetic, and anti-tumor effects. Despite its ethnomedicinal benefits, little information regarding its toxicity is currently available. The aim of this study was to evaluate its potential long-term toxicity and genotoxicity in compliance with test guidelines of the Organization for Economic Cooperation and Development. A 13-week repeat-dose oral toxicity study revealed that body weights of rats were normal after receiving cinnamon extract at up to 2000 mg/kg. High-dose intake of cinnamon extract (2000 mg/kg) showed potential nephrotoxicity and hepatotoxicity to both males and females as evidenced by obvious increases of kidney/liver weight along with a small but statistically elevation of total cholesterol level. Overall findings from genetic toxicity testing battery including Ames test, in vitro mammalian cell micronucleus assay, and in vivo bone marrow micronucleus assay indicated that cinnamon extract was not mutagenic or clastogenic. In conclusion, cinnamon extract may possess potential nephrotoxicity and hepatotoxicity at dose higher than its recommended daily safe dose. Further study is needed to clarify the mechanism involved in its induction of liver and kidney injury.


Assuntos
Cinnamomum aromaticum , Extratos Vegetais/toxicidade , Animais , Feminino , Rim/efeitos dos fármacos , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Testes de Mutagenicidade , Tamanho do Órgão/efeitos dos fármacos , Casca de Planta , Ratos Endogâmicos F344 , Testes de Toxicidade Aguda , Testes de Toxicidade Subcrônica
16.
Regul Toxicol Pharmacol ; 92: 46-54, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29108849

RESUMO

Ecklonia cava (EC) is known to have antioxidant, anti-inflammatory, antidiabetic, and anticancer properties. Despite its wide use and beneficial properties, comprehensive toxicological information regarding EC extract is currently limited. Therefore, the purpose of this study was to investigate acute toxicity, subchronic toxicity, and genotoxicity of enzymatic EC extract according to test guidelines published by Organization for Economic Cooperation and Development. The acute oral LD50 values of this EC extract administered to rats and dogs were estimated to be more than 3000 mg/kg BW. In an oral 13-week toxicity study, changes in body weights of rats exposed to the EC extract up to 3000 mg/kg BW were found to be normal. In addition, repeated doses of EC extract failed to influence any systematic parameters of treatment-related toxic symptoms such as food/water consumption, mortality, urinalysis, hematology, serum biochemistry, organ weight, or histopathology. These results indicated that the no-observed-adverse-effect level for the EC extract was 3000 mg/kg/day for male and female rats. Data obtained from Ames test, chromosome aberration assay, and micronucleus assay indicated that EC extract was not mutagenic or clastogenic. Taken together, these results support the safety of enzymatic EC extract as a potential therapeutic for human consumption against various diseases.


Assuntos
Laminaria/química , Extratos Vegetais/efeitos adversos , Administração Oral , Animais , Cães , Feminino , Masculino , Camundongos , Camundongos Endogâmicos ICR , Testes de Mutagenicidade/métodos , Nível de Efeito Adverso não Observado , Tamanho do Órgão/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Testes de Toxicidade Aguda/métodos , Testes de Toxicidade Subcrônica/métodos
17.
BMC Complement Altern Med ; 18(1): 251, 2018 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-30208908

RESUMO

BACKGROUND: Seed of mature Croton tiglium Linne, also known as Tiglium seed (TS), has been widely used as a natural product due to its several health beneficial properties including anti-tumor and antifungal activities. Despite its ethnomedicinal beneficial properties, toxicological information regarding TS extract, especially its long-term toxicity, is currently limited. Therefore, the objective of the present study was to evaluate acute and subchronic toxicity of TS extract in rats after oral administration following test guidelines of the Organization for Economic Cooperation and Development (OECD). METHODS: Toxicological properties of TS extract were evaluated by toxicity assays to determine its single-dose acute toxicity (125, 250, 500, 1000, or 2000 mg/kg), 14-day repeated-dose toxicity (125, 250, 500, 1000, or 2000 mg/kg) and 13-week repeated-dose toxicity (31.25, 62.5, 125, 250, and 500 mg/kg) in Sprague-Dawley rats and F344 rats. Hematological, serum biochemical, and histopathological parameters were analyzed to determine its median lethal dose (LD50) and no-observed-adverse-effect-level (NOAEL). RESULTS: Oral single dose up to 2000 mg/kg of TS extract resulted in no mortalities or abnormal clinical signs. In 13-week toxicity study, TS extract exhibited no dose-related changes (mortality, body weight, food/water consumption, hematology, clinical biochemistry, organ weight, or histopathology) at dose up to 500 mg/kg, the highest dosage level suggested based on 14-day repeat-dose oral toxicity study. CONCLUSION: Acute oral LD50 of TS extract in rats was estimated to be greater than 2000 mg/kg. NOAEL of TS extract administered orally was determined to be 500 mg/kg/day in both male and female rats. Results from these acute and subchronic toxicity assessments of TS extract under Good Laboratory Practice regulations indicate that TS extract appears to be safe for human consumption.


Assuntos
Croton/química , Extratos Vegetais/toxicidade , Sementes/química , Animais , Peso Corporal/efeitos dos fármacos , Feminino , Masculino , Tamanho do Órgão/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Ratos , Ratos Sprague-Dawley , Testes de Toxicidade
18.
NMR Biomed ; 30(2)2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28028868

RESUMO

Given the strong coupling between the substantia nigra (SN) and striatum (STR) in the early stage of Parkinson's disease (PD), yet only a few studies reported to date that have simultaneously investigated the neurochemistry of these two brain regions in vivo, we performed longitudinal metabolic profiling in the SN and STR of 1-methyl-1,2,3,6-tetrahydropyridine (MPTP)-intoxicated common marmoset monkey models of PD (n = 10) by using proton MRS (1 H-MRS) at 9.4 T. T2 relaxometry was also performed in the SN by using MRI. Data were classified into control, MPTP_2weeks, and MPTP_6-10 weeks groups according to the treatment duration. In the SN, T2 of the MPTP_6-10 weeks group was lower than that of the control group (44.33 ± 1.75 versus 47.21 ± 2.47 ms, p < 0.05). The N-acetylaspartate to total creatine ratio (NAA/tCr) and γ-aminobutyric acid to tCr ratio (GABA/tCr) of the MPTP_6-10 weeks group were lower than those of the control group (0.41 ± 0.04 versus 0.54 ± 0.08 (p < 0.01) and 0.19 ± 0.03 versus 0.30 ± 0.09 (p < 0.05), respectively). The glutathione to tCr ratio (GSH/tCr) was correlated with T2 for the MPTP_6-10 weeks group (r = 0.83, p = 0.04). In the STR, however, GABA/tCr of the MPTP_6-10 weeks group was higher than that of the control group (0.25 ± 0.10 versus 0.16 ± 0.05, p < 0.05). These findings may be an in vivo depiction of the altered basal ganglion circuit in PD brain resulting from the degeneration of nigral dopaminergic neurons and disruption of nigrostriatal dopaminergic projections. Given the important role of non-human primates in translational studies, our findings provide better understanding of the complicated evolution of PD.


Assuntos
1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina , Corpo Estriado/metabolismo , Transtornos Parkinsonianos/metabolismo , Reconhecimento Automatizado de Padrão/métodos , Espectroscopia de Prótons por Ressonância Magnética/métodos , Substância Negra/metabolismo , Animais , Callithrix , Corpo Estriado/diagnóstico por imagem , Corpo Estriado/efeitos dos fármacos , Imageamento por Ressonância Magnética/métodos , Imagem Molecular/métodos , Transtornos Parkinsonianos/induzido quimicamente , Transtornos Parkinsonianos/diagnóstico por imagem , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Substância Negra/diagnóstico por imagem , Substância Negra/efeitos dos fármacos
19.
Acta Pharmacol Sin ; 38(1): 90-99, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27890918

RESUMO

Mast cells are important effector cells in immunoglobulin (Ig) E-mediated allergic reactions such as asthma, atopic dermatitis and rhinitis. Vanillic acid, a natural product, has shown anti-oxidant and anti-inflammatory activities. In the present study, we investigated the anti-allergic inflammatory effects of ortho-vanillic acid (2-hydroxy-3-methoxybenzoic acid, o-VA) that was a derivative of vanillic acid isolated from Amomum xanthioides. In mouse anaphylaxis models, oral administration of o-VA (2, 10, 50 mg/kg) dose-dependently attenuated ovalbumin-induced active systemic anaphylaxis and IgE-mediated cutaneous allergic reactions such as hypothermia, histamine release, IgE production and vasodilation; administration of o-VA also suppressed the mast cell degranulator compound 48/80-induced anaphylaxis. In cultured mast cell line RBL-2H3 and isolated rat peritoneal mast cells in vitro, pretreatment with o-VA (1-100 µmol/L) dose-dependently inhibited DNP-HSA-induced degranulation of mast cells by decreasing the intracellular free calcium level, and suppressed the expression of pro-inflammatory cytokines TNF-α and IL-4. Pretreatment of RBL-2H3 cells with o-VA suppressed DNP-HSA-induced phosphorylation of Lyn, Syk, Akt, and the nuclear translocation of nuclear factor-κB. In conclusion, o-VA suppresses the mast cell-mediated allergic inflammatory response by blocking the signaling pathways downstream of high affinity IgE receptor (FcεRI) on the surface of mast cells.


Assuntos
Anafilaxia/tratamento farmacológico , Anafilaxia/imunologia , Benzoatos/farmacologia , Benzoatos/uso terapêutico , Hipersensibilidade/tratamento farmacológico , Mastócitos/efeitos dos fármacos , Receptores de IgE/imunologia , Ácido Vanílico/análogos & derivados , Anafilaxia/induzido quimicamente , Animais , Cálcio/metabolismo , Degranulação Celular/efeitos dos fármacos , Células Cultivadas , Dinitrofenóis/antagonistas & inibidores , Relação Dose-Resposta a Droga , Hipersensibilidade/imunologia , Imunoglobulina E/efeitos dos fármacos , Mediadores da Inflamação/metabolismo , Masculino , Mastócitos/imunologia , Camundongos , NF-kappa B/metabolismo , Ovalbumina/antagonistas & inibidores , Fosforilação/efeitos dos fármacos , Ratos , Receptores de IgE/antagonistas & inibidores , Albumina Sérica/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , p-Metoxi-N-metilfenetilamina/antagonistas & inibidores
20.
Regul Toxicol Pharmacol ; 88: 87-95, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28487065

RESUMO

Artemisia capillaris (AC) has been used as an alternative therapy in obesity, atopic dermatitis, and liver diseases through several biological activity including anti-steatotic, antioxidant, and anti-inflammatory activities. Despite its ethnomedicinal benefits, no sufficient background information is available about the long-term safety and genotoxicity of the AC extract. Therefore, the present study was carried out to investigate the 13-week subchronic toxicity and genotoxicity of the AC extract according to the test guidelines published by the Organization for Economic Cooperation and Development. In the 13-week toxicity study using doses of 25, 74, 222, 667, and 2000 mg/kg body weight, oral administration of the AC extract in male and female rats did not result in any significant adverse effects in food/water consumption, body weight, mortality, hematology, serum biochemistry, organ weight and histopathology. Accordingly, the no-observed-adverse-effect level in rats of both genders was established for the AC extract at 2000 mg/kg/day, the highest dose level tested. In addition, the AC extract was not genotoxic in a battery of tests including Ames test, in vitro chromosome aberration assay and in vivo micronucleus assay. In conclusion, we demonstrated that the AC extract is considered as a safe traditional medicine for human consumption.


Assuntos
Artemisia/química , Extratos Vegetais/toxicidade , Administração Oral , Animais , Peso Corporal , Ingestão de Líquidos , Ingestão de Alimentos , Feminino , Masculino , Testes para Micronúcleos , Nível de Efeito Adverso não Observado , Tamanho do Órgão , Extratos Vegetais/administração & dosagem , Ratos , Ratos Sprague-Dawley , Testes de Toxicidade Subcrônica
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