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1.
Toxicol Appl Pharmacol ; 475: 116628, 2023 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-37506978

RESUMEN

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.


Asunto(s)
Linfoma de Burkitt , Leucemia , Receptores Quiméricos de Antígenos , Masculino , Femenino , Humanos , Ratones , Animales , Receptores Quiméricos de Antígenos/genética , Receptores Quiméricos de Antígenos/uso terapéutico , Xenoinjertos , Cinética , Linfoma de Burkitt/tratamiento farmacológico , Leucemia/tratamiento farmacológico , Antígenos CD19 , Tratamiento Basado en Trasplante de Células y Tejidos
2.
Cell Biol Toxicol ; 39(1): 165-182, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-34283317

RESUMEN

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.


Asunto(s)
Conexina 43 , beta Catenina , Ratas , Animales , Conexina 43/metabolismo , Conexina 43/farmacología , Ratas Endogámicas F344 , beta Catenina/metabolismo , Vía de Señalización Wnt , Fosfatidilinositol 3-Quinasas/metabolismo , Uniones Comunicantes/metabolismo , Pirenos/metabolismo , Pirenos/farmacología , Proteínas Nucleares/metabolismo
3.
Am J Primatol ; 85(9): e23532, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37357545

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-35266161

RESUMEN

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.


Asunto(s)
Preeclampsia , Microangiopatías Trombóticas , Animales , Callithrix , Callitrichinae , Cesárea/efectos adversos , Cesárea/veterinaria , Femenino , Preeclampsia/diagnóstico , Embarazo , Microangiopatías Trombóticas/diagnóstico , Microangiopatías Trombóticas/etiología , Microangiopatías Trombóticas/terapia
5.
J Med Primatol ; 51(4): 253-255, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35352840

RESUMEN

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.


Asunto(s)
Callithrix , Neumonía por Aspiración , Animales , Dilatación , Femenino , Neumonía por Aspiración/etiología , Neumonía por Aspiración/veterinaria , Vómitos , Pérdida de Peso
6.
J Appl Toxicol ; 42(11): 1832-1842, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35792566

RESUMEN

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.


Asunto(s)
Cosméticos , Dermatitis Alérgica por Contacto , Alternativas a las Pruebas en Animales/métodos , Animales , Dermatitis Alérgica por Contacto/etiología , Humanos , Aprendizaje Automático , Piel
7.
Drug Chem Toxicol ; 44(3): 268-276, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-31215257

RESUMEN

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.


Asunto(s)
Colagogos y Coleréticos/toxicidad , Ácido Taurodesoxicólico/toxicidad , Animales , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Colagogos y Coleréticos/administración & dosificación , Relación Dosis-Respuesta a Droga , Edema/inducido químicamente , Femenino , Infusiones Intravenosas , Dosificación Letal Mediana , Masculino , Ratas , Ratas Sprague-Dawley , Ácido Taurodesoxicólico/administración & dosificación , Pruebas de Toxicidad Aguda , Pruebas de Toxicidad Subaguda
8.
Drug Chem Toxicol ; 44(2): 161-169, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31215246

RESUMEN

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.


Asunto(s)
Antiinflamatorios/toxicidad , Ácido Taurodesoxicólico/toxicidad , Animales , Antiinflamatorios/administración & dosificación , Perros , Relación Dosis-Respuesta a Droga , Femenino , Masculino , Nivel sin Efectos Adversos Observados , Ácido Taurodesoxicólico/administración & dosificación , Pruebas de Toxicidad Aguda , Pruebas de Toxicidad Subaguda
9.
Int J Mol Sci ; 22(16)2021 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-34445302

RESUMEN

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.


Asunto(s)
Diferenciación Celular/genética , Epigénesis Genética/fisiología , Miocitos Cardíacos/fisiología , Animales , Tratamiento Basado en Trasplante de Células y Tejidos/métodos , Células Cultivadas , Células Madre Embrionarias/fisiología , Humanos , Células Madre Pluripotentes Inducidas/fisiología , Medicina Regenerativa/métodos , Ingeniería de Tejidos/métodos
10.
Regul Toxicol Pharmacol ; 116: 104757, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32758521

RESUMEN

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.


Asunto(s)
Modelos Animales , Toxicología/métodos , Animales , Proyectos de Investigación , Toxicología/ética
11.
J Nanosci Nanotechnol ; 19(3): 1729-1733, 2019 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-30469255

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-30469261

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-30845640

RESUMEN

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.


Asunto(s)
Gonadotropina Coriónica/farmacología , Factor de Crecimiento Epidérmico/farmacología , Perfilación de la Expresión Génica/métodos , Oocitos/efectos de los fármacos , Animales , Proteína Morfogenética Ósea 15/genética , Callithrix , Femenino , Fertilización In Vitro , Hormona Folículo Estimulante , Perfilación de la Expresión Génica/veterinaria , Humanos , Técnicas de Maduración In Vitro de los Oocitos , MicroARNs/genética , Modelos Animales , Oocitos/metabolismo , Oogénesis , Glicoproteínas de la Zona Pelúcida/genética
14.
J Nanosci Nanotechnol ; 18(9): 6562-6564, 2018 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-29677834

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-29501463

RESUMEN

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.


Asunto(s)
Cinnamomum aromaticum , Extractos Vegetales/toxicidad , Animales , Femenino , Riñón/efectos de los fármacos , Riñón/patología , Hígado/efectos de los fármacos , Hígado/patología , Masculino , Pruebas de Mutagenicidad , Tamaño de los Órganos/efectos de los fármacos , Corteza de la Planta , Ratas Endogámicas F344 , Pruebas de Toxicidad Aguda , Pruebas de Toxicidad Subcrónica
16.
Regul Toxicol Pharmacol ; 92: 46-54, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29108849

RESUMEN

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.


Asunto(s)
Laminaria/química , Extractos Vegetales/efectos adversos , Administración Oral , Animales , Perros , Femenino , Masculino , Ratones , Ratones Endogámicos ICR , Pruebas de Mutagenicidad/métodos , Nivel sin Efectos Adversos Observados , Tamaño de los Órganos/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Pruebas de Toxicidad Aguda/métodos , Pruebas de Toxicidad Subcrónica/métodos
17.
BMC Complement Altern Med ; 18(1): 251, 2018 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-30208908

RESUMEN

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.


Asunto(s)
Croton/química , Extractos Vegetales/toxicidad , Semillas/química , Animales , Peso Corporal/efectos de los fármacos , Femenino , Masculino , Tamaño de los Órganos/efectos de los fármacos , Extractos Vegetales/administración & dosificación , Extractos Vegetales/química , Ratas , Ratas Sprague-Dawley , Pruebas de Toxicidad
18.
NMR Biomed ; 30(2)2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28028868

RESUMEN

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.


Asunto(s)
1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina , Cuerpo Estriado/metabolismo , Trastornos Parkinsonianos/metabolismo , Reconocimiento de Normas Patrones Automatizadas/métodos , Espectroscopía de Protones por Resonancia Magnética/métodos , Sustancia Negra/metabolismo , Animales , Callithrix , Cuerpo Estriado/diagnóstico por imagen , Cuerpo Estriado/efectos de los fármacos , Imagen por Resonancia Magnética/métodos , Imagen Molecular/métodos , Trastornos Parkinsonianos/inducido químicamente , Trastornos Parkinsonianos/diagnóstico por imagen , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Sustancia Negra/diagnóstico por imagen , Sustancia Negra/efectos de los fármacos
19.
Acta Pharmacol Sin ; 38(1): 90-99, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27890918

RESUMEN

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.


Asunto(s)
Anafilaxia/tratamiento farmacológico , Anafilaxia/inmunología , Benzoatos/farmacología , Benzoatos/uso terapéutico , Hipersensibilidad/tratamiento farmacológico , Mastocitos/efectos de los fármacos , Receptores de IgE/inmunología , Ácido Vanílico/análogos & derivados , Anafilaxia/inducido químicamente , Animales , Calcio/metabolismo , Degranulación de la Célula/efectos de los fármacos , Células Cultivadas , Dinitrofenoles/antagonistas & inhibidores , Relación Dosis-Respuesta a Droga , Hipersensibilidad/inmunología , Inmunoglobulina E/efectos de los fármacos , Mediadores de Inflamación/metabolismo , Masculino , Mastocitos/inmunología , Ratones , FN-kappa B/metabolismo , Ovalbúmina/antagonistas & inhibidores , Fosforilación/efectos de los fármacos , Ratas , Receptores de IgE/antagonistas & inhibidores , Albúmina Sérica/antagonistas & inhibidores , Transducción de Señal/efectos de los fármacos , p-Metoxi-N-metilfenetilamina/antagonistas & inhibidores
20.
Regul Toxicol Pharmacol ; 88: 87-95, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28487065

RESUMEN

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.


Asunto(s)
Artemisia/química , Extractos Vegetales/toxicidad , Administración Oral , Animales , Peso Corporal , Ingestión de Líquidos , Ingestión de Alimentos , Femenino , Masculino , Pruebas de Micronúcleos , Nivel sin Efectos Adversos Observados , Tamaño de los Órganos , Extractos Vegetales/administración & dosificación , Ratas , Ratas Sprague-Dawley , Pruebas de Toxicidad Subcrónica
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