Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 14 de 14
Filtrar
1.
Toxicol Res ; 39(2): 317-331, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37008697

RESUMO

The migratory locust, Locusta migratoria (Orthoptera: Acrididae), is a well-known edible insect which may serve as new source of human food and animal feed. However, potential toxicity and food safety of L. migratoria had not been investigated extensively until now. Therefore, in this study, we aimed to investigate toxicity of freeze-dried powder of L. migratoria (fdLM) and identify allergic components in ELISA and PCR techniques. In this subchronic study, fdLM was administered once daily by oral gavage at the doses of 750, 1500, and 3000 mg/kg/day. No toxicological changes were observed in both sexes of rats for 13 weeks in accordance with the OECD guidelines and GLP conditions. In addition, fdLM did not induced increases of serum immunoglobulin E and 21 homologous proteins were not detected under our present conditions. In conclusion, the NOAEL (no-observed-adverse-effect level) was 3000 mg/kg/day and no target organ was identified in both sexes. In conclusion, we found that fdLM is safe with no adverse effects and offers the potential of its use as an edible ingredient or other biological uses.

2.
Toxicol Rep ; 9: 499-504, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35345861

RESUMO

Local lymph node assay (LLNA) is a predictive in vivo method to provide estimates of relative potency and to contribute to risk assessment/risk management regarding skin sensitizing potency of chemicals and formulations as a stand-alone alternative test. In addition, LLNA is relatively rapid and cost-effective compared to the Buehler method (Guinea pig test), and confers important animal welfare benefits. CBA/J and BALB/c strains are widely commercially available and have been evaluated by formal LLNA validation studies. However, the LLNA method using BrdU with ELISA, unlike other LLNA methods (OECD TG 429, 442 A, 442B), has not been previously validated. Therefore, in this study a validation method was performed to evaluate if the LLNA:BrdU-ELISA method could also be used to identify sensitizers among chemicals listed in OECD TG 429 using CBA/J and BALB/c strains. Here, we newly found that the LLNA:BrdU-ELISA validation method correctly identified 12 of 13 sensitizers in the BALB/c, 11 of 13 sensitizers in the CBA/J, and 3 of 5 non-sensitizers were identified in the two strains. Collectively, we found that the results of LLNA:BrdU-ELISA method provide a similar level of performance for accuracy and sensitivity in two mouse strains BALB/c and CBA/J.

3.
Korean J Parasitol ; 59(4): 329-339, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34470084

RESUMO

Ion channels are important targets of anthelmintic agents. In this study, we identified 3 types of ion channels in Ascaris suum tissue incorporated into planar lipid bilayers using an electrophysiological technique. The most frequent channel was a large-conductance cation channel (209 pS), which accounted for 64.5% of channels incorporated (n=60). Its open-state probability (Po) was ~0.3 in the voltage range of -60~+60 mV. A substate was observed at 55% of the main-state. The permeability ratio of Cl- to K+ (PCl/PK) was ~0.5 and PNa/PK was 0.81 in both states. Another type of cation channel was recorded in 7.5% of channels incorporated (n=7) and discriminated from the large-conductance cation channel by its smaller conductance (55.3 pS). Its Po was low at all voltages tested (~0.1). The third type was an anion channel recorded in 27.9% of channels incorporated (n=26). Its conductance was 39.0 pS and PCl/PK was 8.6±0.8. Po was ~1.0 at all tested potentials. In summary, we identified 2 types of cation and 1 type of anion channels in Ascaris suum. Gating of these channels did not much vary with voltage and their ionic selectivity is rather low. Their molecular nature, functions, and potentials as anthelmintic drug targets remain to be studied further.


Assuntos
Ascaris suum , Bicamadas Lipídicas , Animais , Canais Iônicos , Potenciais da Membrana
4.
Artigo em Inglês | MEDLINE | ID: mdl-35003288

RESUMO

Aster glehni, a traditional plant on Ulleung Island in the Republic of Korea, has been recognized for its multiple medicinal properties. However, potential toxicity and safety analyses of A. glehni have not been previously investigated. Therefore, this study aimed to evaluate the safety profile of ethanolic extract of A. glehni leaves and stems (EAG) in terms of genotoxicity and subchronic oral animal toxicity under OECD guidelines and GLP conditions. Toxicological assessments were performed at doses of 1,250, 2,500, and 5,000 mg/kg/day in a 13-week oral repeated-dose toxicity study of EAG in male and female SD rats. In addition, an Ames test, an in vitro mammalian chromosomal aberration test, and a micronucleus test were performed. No toxicological changes in clinical signs, body weights, water and food consumption, urinalysis, hematology, clinical biochemistry, gross findings, and histopathological examinations were observed in subchronic oral animal toxicity. In addition, EAG gave negative results when evaluated using in vitro and in vivo genotoxicity tests. In conclusion, the no-observed-adverse-effect level (NOAEL) of EAG was considered to be 5,000 mg/kg/day, and no target organs were identified in both sexes of rats. EAG was also classified as nonmutagenic and nonclastogenic in genotoxicity testing. Collectively, these results show a lack of general toxicity and genotoxicity for EAG that supports clinical work for development as a herbal medicine.

5.
Foods ; 9(8)2020 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-32722267

RESUMO

Zophobas atratus (Coleoptera: Tenebrionidae), the giant mealworm beetle, is known as an edible insect containing a high protein content which may serve as new sources of human food and animal feed. However, potential toxicity and food safety analyses of Z. atratus have not been previously investigated. Therefore, in this study, we aimed to evaluate toxicity of freeze-dried skimmed powder of Z. atratus larvae (frpfdZAL), known as the super mealworm. Toxicological assessments were performed at the doses of 1250, 2500, and 5000 mg/kg/day in a 2- and a 13-week oral repeated-dose toxicity study of frpfdZAL in male and female Sprague-Dawley (SD) rats in accordance with the Organisation for Economic Co-operation and Development (OECD) guidelines and the principles of Good Laboratory Practice (GLP). No toxicological changes in clinical signs, body weights, water and food consumption, urinalysis, hematology, clinical biochemistry, gross findings, and histopathological examinations were observed. In conclusion, the no-observed-adverse-effect level (NOAEL) of frpfdZAL was 5000 mg/kg/day and target organ was not identified in both sexes of rats. In addition, frpfdZAL did not induce increases of serum ImmunoglobulinE (IgE), an identifier of allergic reactions in rats. Collectively, these results suggest that frpfdZAL is safe with no adverse effects, and able to be applied as an edible ingredient or other biological uses.

6.
Regul Toxicol Pharmacol ; 115: 104686, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32450131

RESUMO

Several studies report that the therapeutic mechanism of action of mesenchymal stem/stromal cells (MSCs) is mainly mediated by paracrine factors that are released from MSCs such as exosomes. Exosomes are nano-sized extracellular vesicles that are transferred to target cells for cell-to-cell communication. Although MSC-derived exosomes (MSC-exosomes) are suggested as novel cell-free therapeutics for various human diseases, evaluation studies for the safety and toxicity of MSC-exosomes are limited. The purpose of our study was to evaluate the toxicological profile, including skin sensitization, photosensitization, eye and skin irritation, and acute oral toxicity using exosomes derived from human adipose tissue-derived MSCs (ASC-exosomes) in accordance with the OECD guidelines and the principles of Good Laboratory Practice. The ASC-exosomes were classified as a potential non-sensitizer in the skin sensitization test, UN GHS no category in the eye irritation test, and as a skin non-irritant in the skin irritation test, and did not induce any toxicity in the phototoxicity test or in acute oral toxicity testing. Our findings are the first to suggest that ASC-exosomes are safe for use as a topical treatment, with no adverse effects in toxicological testing, and have potential application as a therapeutic agent, cosmetic ingredient, or for other biological uses.


Assuntos
Exossomos , Administração Cutânea , Animais , Células 3T3 BALB , Olho , Feminino , Humanos , Células-Tronco Mesenquimais , Camundongos , Células RAW 264.7 , Ratos Sprague-Dawley , Pele , Testes de Toxicidade
7.
Toxicol Rep ; 7: 241-253, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32025500

RESUMO

l-threonine, l-tryptophan and l-valine play a fundamental role in animal and human nutrition as essential amino acids required for normal growth. In addition, each amino acid is codified as a generally recognized as safe (GRAS) amino acid for the use in animal feed additives and presents no exposure risk from animal to humans consuming tissues or products from the target animal. Taking into account the important role of mutagenicity and genotoxicity in the risk of the three amino acid additives (l-threonine, l-tryptophan, and l-valine) fermentation products and other unknown impurities and derivatives from Corynebacterium glutamicum (C. glutamicum), the safety evaluation of these amino acid additives is not performed. Therefore, the purpose of this study is to evaluate toxicological effects, including Ames test, an in vitro mammalian chromosomal aberration test and an acute oral animal toxicity of the three amino acid additives in accordance with the Organisation for Economic Co-operation and Development (OECD) guidelines and the principles of Good Laboratory Practice (GLP). As a result, these amino acid additives were classified as non-mutagenic and non-clastogenic, and did not induce any toxicity in acute oral toxicity test. Collectively, these results suggest that the three amino acid additives are safe with no adverse effects, and able to be applied as an ingredient or other biological uses.

8.
Am J Med Genet A ; 173(11): 2893-2897, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28985029

RESUMO

Craniosynostosis presents either as a nonsyndromic congenital anomaly or as a finding in nearly 200 genetic syndromes. Our previous genome-wide association study of sagittal nonsyndromic craniosynostosis identified associations with variants downstream from BMP2 and intronic in BBS9. Because no coding variants in BMP2 were identified, we hypothesized that conserved non-coding regulatory elements may alter BMP2 expression. In order to identify and characterize noncoding regulatory elements near BMP2, two conserved noncoding regions near the associated region on chromosome 20 were tested for regulatory activity with a Renilla luciferase assay. For a 711 base pair noncoding fragment encompassing the most strongly associated variant, rs1884302, the luciferase assay showed that the risk allele (C) of rs1884302 drives higher expression of the reporter than the common allele (T). When this same DNA fragment was tested in zebrafish transgenesis studies, a strikingly different expression pattern of the green fluorescent reporter was observed depending on whether the transgenic fish had the risk (C) or the common (T) allele at rs1884302. The in vitro results suggest that altered BMP2 regulatory function at rs1884302 may contribute to the etiology of sagittal nonsyndromic craniosynostosis. The in vivo results indicate that differences in regulatory activity depend on the presence of a C or T allele at rs1884302.


Assuntos
Proteína Morfogenética Óssea 2/genética , Anormalidades Congênitas/genética , Craniossinostoses/genética , Predisposição Genética para Doença , Alelos , Animais , Animais Geneticamente Modificados/genética , Anormalidades Congênitas/fisiopatologia , Sequência Conservada , Regulação da Expressão Gênica/genética , Estudo de Associação Genômica Ampla , Humanos , Polimorfismo de Nucleotídeo Único , Sequências Reguladoras de Ácido Nucleico/genética , Peixe-Zebra/genética
9.
Cleft Palate Craniofac J ; 51(1): 115-9, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23566293

RESUMO

OBJECTIVE: The MAPK/ERK signaling pathway has been implicated in several craniosynostosis syndromes and represents a plausible target for therapeutic management of craniosynostosis. The causes of sagittal nonsyndromic craniosynostosis (sNSC) have not been well understood and the role that MAPK/ERK signaling cascade plays in this condition warrants an investigation. We hypothesized that MAPK-signaling is misregulated in calvarial osteoblasts derived from patients with sNSC. METHODS: In order to analyze if the MAPK/ERK pathway is perturbed in sNSC, we established primary calvarial osteoblast cell lines from patients undergoing surgery for correction of this congenital anomaly. Appropriate negative and positive control cell lines were used for comparison, and we examined the levels of phosphorylated ERK by immunoblotting. RESULTS: Primary osteoblasts from patients with sNSC showed no difference in ERK1/2 phosphorylation with or without FGF2 stimulation as compared with control osteoblasts. CONCLUSION: Under the described test conditions, we did not observe convincing evidence that MAPK/ERK signaling contributes to the development of sNSC.


Assuntos
Craniossinostoses/metabolismo , MAP Quinase Quinase Quinase 1/metabolismo , Osteoblastos/metabolismo , Estudos de Casos e Controles , Células Cultivadas , Humanos , Immunoblotting , Fosforilação , Transdução de Sinais , Crânio/citologia
10.
Biochem Pharmacol ; 86(6): 782-90, 2013 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-23928189

RESUMO

Trapidil, a platelet-derived growth factor antagonist, was originally developed as a vasodilator and anti-platelet agent and has been used to treat patients with ischemic coronary heart, liver, and kidney disease. In this study, we investigated the effects of trapidil on osteoclastogenesis and elucidated the possible mechanism of action of trapidil. Trapidil strongly inhibited osteoclast formation in co-cultures of bone marrow cells and osteoblasts without affecting receptor activator of NF-κB ligand (RANKL) or osteoprotegerin expression in osteoblasts. In addition, trapidil suppressed RANKL-induced osteoclast formation from osteoclast precursors. Trapidil reduced RANKL-induced expression of nuclear factor of activated T cells, cytoplasmic 1 (NFATc1), a master transcription factor for osteoclastogenesis, without affecting the expression of c-Fos that functions as a key upstream activator of NFATc1 during osteoclastogenesis. Ectopic expression of a constitutively active form of NFATc1 reversed the anti-osteoclastogenic effect of trapidil, indicating that NFATc1 is a critical target of the anti-osteoclastogenic action of trapidil. RANKL-induced calcium oscillation and Pim-1 expression, which are required for NFATc1 induction and osteoclastogenesis, were abrogated by trapidil. Consistent with the in vitro results, trapidil had a potent inhibitory effect on osteoclast formation and bone resorption induced by interleukin-1 in an animal model. Taken together, our data demonstrate that trapidil abrogates RANKL-induced calcium oscillation and Pim-1 expression required for NFATc1 induction, thereby inhibiting osteoclastogenesis.


Assuntos
Conservadores da Densidade Óssea/farmacologia , Reabsorção Óssea/prevenção & controle , Osso e Ossos/efeitos dos fármacos , Fatores de Transcrição NFATC/antagonistas & inibidores , Osteoclastos/efeitos dos fármacos , Inibidores da Agregação Plaquetária/farmacologia , Trapidil/farmacologia , Animais , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Células da Medula Óssea/patologia , Reabsorção Óssea/induzido quimicamente , Reabsorção Óssea/genética , Reabsorção Óssea/patologia , Osso e Ossos/metabolismo , Osso e Ossos/patologia , Cálcio/metabolismo , Técnicas de Cocultura , Regulação da Expressão Gênica/efeitos dos fármacos , Interleucina-1 , Masculino , Camundongos , Camundongos Endogâmicos ICR , Fatores de Transcrição NFATC/genética , Fatores de Transcrição NFATC/metabolismo , Osteoclastos/metabolismo , Osteoclastos/patologia , Osteoprotegerina/genética , Osteoprotegerina/metabolismo , Proteínas Proto-Oncogênicas c-fos/genética , Proteínas Proto-Oncogênicas c-fos/metabolismo , Proteínas Proto-Oncogênicas c-pim-1/genética , Proteínas Proto-Oncogênicas c-pim-1/metabolismo , Ligante RANK/genética , Ligante RANK/metabolismo , Transdução de Sinais
11.
Hum Mutat ; 33(12): 1626-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22829454

RESUMO

Craniosynostosis is the early fusion of one or more sutures of the infant skull and is a common defect occurring in approximately 1 of every 2,500 live births. Nonsyndromic craniosynostosis (NSC) accounts for approximately 80% of all cases and is thought to have strong genetic determinants that are yet to be identified. ALX4 is a homeodomain transcription factor with known involvement in osteoblast regulation. By direct sequencing of the ALX4 coding region in sagittal or sagittal-suture-involved nonsyndromic craniosynostosis probands, we identified novel, nonsynonymous, familial variants in three of 203 individuals with NSC. Using dual-luciferase assay we show that two of these variants (V7F and K211E) confer a significant gain-of-function effect on ALX4. Our results suggest that ALX4 variants may have an impact on the genetic etiology of NSC.


Assuntos
Craniossinostoses/genética , Proteínas de Ligação a DNA/genética , Mutação de Sentido Incorreto , Fatores de Transcrição/genética , Sequência de Aminoácidos , Sequência de Bases , Sequência Conservada , Frequência do Gene , Estudos de Associação Genética , Humanos , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA
12.
FEBS Lett ; 586(10): 1516-21, 2012 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-22673519

RESUMO

Fibroblast growth factor receptors (FGFRs) play critical roles in craniofacial and skeletal development via multiple signaling pathways including MAPK, PI3K/AKT, and PLC-?. FGFR-mediated signaling is modulated by several regulators. Proteins with leucine-rich repeat (LRR) and/or immunoglobulin (IG) superfamily domains have been suggested to interact with FGFRs. In addition, fibronectin leucine-rich repeat transmembrane protein 3 (FLRT3) has been shown to modulate the FGFR-mediated signaling via the fibronectin type III (FNIII) domain. Therefore proteins with LRR, IG, and FNIII are candidate regulators of the FGFRs. Here we identify leucine-rich repeat, immunoglobulin-like and transmembrane domain 3 (LRIT3) as a regulator of the FGFRs.


Assuntos
Imunoglobulinas/metabolismo , Leucina/metabolismo , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/fisiologia , Sequências Repetitivas de Aminoácidos , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , Primers do DNA , Humanos , Dados de Sequência Molecular , Fosfolipases/metabolismo , Proteínas Quinases/metabolismo , Transdução de Sinais
13.
J Biol Chem ; 287(13): 10134-10144, 2012 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-22298774

RESUMO

COPII proteins are essential for exporting most cargo molecules from the endoplasmic reticulum. The membrane-facing surface of the COPII proteins (especially SEC23-SEC24) interacts directly or indirectly with the cargo molecules destined for exit. As we characterized the SEC23A mutations at the SEC31 binding site identified from patients with cranio-lenticulo-sutural dysplasia, we discovered that the SEC23-SEC31 interface can also influence cargo selection. Remarkably, M702V SEC23A does not compromise COPII assembly, vesicle size, and packaging of cargo molecules into COPII vesicles that we have tested but induces accumulation of procollagen in the endoplasmic reticulum when expressed in normal fibroblasts. We observed that M702V SEC23A activates SAR1B GTPase more than wild-type SEC23A when SEC13-SEC31 is present, indicating that M702V SEC23A causes premature dissociation of COPII from the membrane. Our results indicate that a longer stay of COPII proteins on the membrane is required to cargo procollagen than other molecules and suggest that the SEC23-SEC31 interface plays a critical role in capturing various cargo molecules.


Assuntos
Vesículas Revestidas pelo Complexo de Proteína do Envoltório/metabolismo , Retículo Endoplasmático/metabolismo , Pró-Colágeno/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Substituição de Aminoácidos , Animais , Vesículas Revestidas pelo Complexo de Proteína do Envoltório/genética , Linhagem Celular Tumoral , Retículo Endoplasmático/genética , Humanos , Mutação de Sentido Incorreto , Pró-Colágeno/genética , Ligação Proteica , Transporte Proteico/fisiologia , Ratos , Proteínas de Transporte Vesicular/genética
14.
J Vet Sci ; 4(2): 129-36, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-14610365

RESUMO

To investigate the neutralizing effect of N-acetylcysteine (NAC) and selenium (Se) against doxorubicin (DOX) toxicity in rats, NAC (140 mg/kg, p.o.) and Se (0.5 mg/kg, p.o.) were administered for 2 days before DOX injection and then 3 times a week. Cell viability and the level of lipid peroxidation were examined in cultured-rat astrocytes. Severe morphologic changes in the kidney of DOX group; thickening of Bowmans capsule, presence of multifocal tubular casts were observed, but not in the other treated groups. Vacuoles in some hepatic cells and focal aggregation of stellate macrophages were also detected in DOX group, but not in the other treated groups. However, the severe inhibition of spermatogenesis was found in all treated groups. The cell viability of DOX (10 mg/ml) treated group and NAC (5 mM) or Se (0.001 mg/ml) combined-treated group was 52.5-/+2.0 %, 85.3-/+4.5 % and 75.5-/+1.6 %, respectively. In MDA (malondialdehyde) assay, the level of lipid peroxidation on DOX (10 mg/ml), NAC (5 mM) and Se (0.001 mg/ml) was 0.77-/+0.06, 0.35-/+0.06 and 0.54-/+0.11 nmol/mg protein, respectively. Thus, it is known that NAC and Se have protective effects in kidney and liver but not in the testes. Morphological change was not detected in brain and heart in all groups for experiment period. From this in vitro study, it is known that NAC and Se protect well the astrocytes against DOX induced-cell damage.


Assuntos
Acetilcisteína/farmacologia , Astrócitos/citologia , Doxorrubicina/toxicidade , Fígado/efeitos dos fármacos , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/patologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Doxorrubicina/antagonistas & inibidores , Fígado/citologia , Fígado/patologia , Masculino , Ratos , Ratos Sprague-Dawley , Espermatócitos/citologia , Espermatócitos/efeitos dos fármacos , Espermatócitos/patologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA