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1.
No Shinkei Geka ; 52(2): 389-398, 2024 Mar.
Artigo em Japonês | MEDLINE | ID: mdl-38514129

RESUMO

In STA-MCA bypass surgery, it is important to select the optimal recipient using preoperative simulation to avoid complications. We report a preoperative simulation for STA-MCA bypass using the Brain LAB iPLAN platform®BRAIN LAB)and the 3DCG simulation software GRID®Kompath). Here, we introduce the basics and applications of preoperative simulation for occlusive atherosclerotic lesions and present a target bypass for periventricular anastomosis and peripheral vessels of aneurysms in Moyamoya disease. By creating and visualizing 3D fusion images, the optimal donor and recipient can be selected. Determining the skin incision and extent of craniotomy according to the case is also applicable to the minimally invasive STA-MCA bypass. Preoperative simulations enable accurate pinpoint bypass surgery and prevent complications.


Assuntos
Revascularização Cerebral , Doença de Moyamoya , Humanos , Revascularização Cerebral/métodos , Artéria Cerebral Média/cirurgia , Artérias Temporais , Doença de Moyamoya/diagnóstico por imagem , Doença de Moyamoya/cirurgia , Doença de Moyamoya/complicações , Encéfalo
2.
Biol Pharm Bull ; 46(7): 946-954, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37183024

RESUMO

Allergic contact dermatitis (ACD) is a common skin disorder caused by contact with allergens. The optimal treatment for ACD is to avoid contact with allergens. However, in some cases, avoiding exposure is not possible when the allergens are unknown. Therefore, establishing treatment methods other than allergen avoidance is important. We previously reported that the continuous administration of methionine, an essential amino acid, in a mouse model of atopic dermatitis alleviated its symptoms. In the present study, we investigated the effect of methionine on a mouse model of ACD caused by 1-fluoro-2,4-dinitrobenzene (DNFB). Differences in the effect of methionine were observed in DNFB-induced ACD model mice based on the mouse strain used. This difference was attributed to the suppression of hepatic dimethylglycine (DMG) production, which is associated with the suppression of hepatic betaine-homocysteine methyltransferase (Bhmt) expression by ACD. Although we did not reveal the mechanism underlying DMG suppression, our study suggests the presence of interactions between the liver and skin in dermatitis, such as the regulation of hepatic metabolic enzyme expression in dermatitis and the alleviation of dermatitis symptoms by the hepatic metabolism status of DMG.


Assuntos
Dermatite Alérgica de Contato , Metionina , Camundongos , Animais , Dinitrofluorbenzeno/toxicidade , Dermatite Alérgica de Contato/tratamento farmacológico , Alérgenos , Racemetionina
3.
Biol Pharm Bull ; 44(11): 1598-1606, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34719638

RESUMO

Excessive, chronic alcohol consumption can lead to alcoholic liver disease. The etiology of alcoholic liver disease is multifactorial and is influenced by alterations in gene expression and changes in fatty acid metabolism, oxidative stress, and insulin resistance. These events can lead to steatosis, fibrosis, and eventually to cirrhosis and liver cancer. Many of these functions are regulated by peroxisome proliferator-activated receptors (PPARs). Thus, it is not surprising that PPARs can modulate the mechanisms that cause alcoholic liver disease. While the roles of PPARα and PPARγ are clearer, the role of PPARß/δ in alcoholic liver disease requires further clarification. This review summarizes the current understanding based on recent studies that indicate that PPARß/δ can likely be targeted for the treatment and/or the prevention of alcoholic liver disease.


Assuntos
Hepatopatias Alcoólicas/prevenção & controle , PPAR gama/efeitos dos fármacos , PPAR beta/efeitos dos fármacos , Animais , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Hepatopatias Alcoólicas/tratamento farmacológico
4.
Int J Mol Sci ; 22(10)2021 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-34069420

RESUMO

Selenium-binding protein 1 (Selenbp1) is a 2,3,7,8-tetrechlorodibenzo-p-dioxin inducible protein whose function is yet to be comprehensively elucidated. As the highly homologous isoform, Selenbp2, is expressed at low levels in the kidney, it is worthwhile comparing wild-type C57BL mice and Selenbp1-deficient mice under dioxin-free conditions. Accordingly, we conducted a mouse metabolomics analysis under non-dioxin-treated conditions. DNA microarray analysis was performed based on observed changes in lipid metabolism-related factors. The results showed fluctuations in the expression of numerous genes. Real-time RT-PCR confirmed the decreased expression levels of the cytochrome P450 4a (Cyp4a) subfamily, known to be involved in fatty acid ω- and ω-1 hydroxylation. Furthermore, peroxisome proliferator-activated receptor-α (Pparα) and retinoid-X-receptor-α (Rxrα), which form a heterodimer with Pparα to promote gene expression, were simultaneously reduced. This indicated that reduced Cyp4a expression was mediated via decreased Pparα and Rxrα. In line with this finding, increased levels of leukotrienes and prostaglandins were detected. Conversely, decreased hydrogen peroxide levels and reduced superoxide dismutase (SOD) activity supported the suppression of the renal expression of Sod1 and Sod2 in Selenbp1-deficient mice. Therefore, we infer that ablation of Selenbp1 elicits oxidative stress caused by increased levels of superoxide anions, which alters lipid metabolism via the Pparα pathway.


Assuntos
Metabolismo dos Lipídeos/genética , Proteínas de Ligação a Selênio/metabolismo , Animais , Citocromo P-450 CYP4A/metabolismo , Expressão Gênica , Rim/patologia , Lipídeos/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Estresse Oxidativo/genética , PPAR alfa/metabolismo , PPAR alfa/fisiologia , RNA Mensageiro/genética , Receptor X Retinoide alfa/metabolismo , Receptor X Retinoide alfa/fisiologia , Proteínas de Ligação a Selênio/genética , Fatores de Transcrição/metabolismo
5.
Biochem Biophys Res Commun ; 531(2): 215-222, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-32798015

RESUMO

The functional role of fatty acid 2-hydroxylase (FA2H) is controversial in the field of cancer biology due to the dual role of FA2H, particularly related to its interaction with triple-negative breast cancer (TNBC). A previous biochemical- and clinical-focused study suggested that FA2H could dampen TNBC aggressiveness. However, another epidemiological study demonstrated that FA2H expression is associated with shorter disease-free survival in TNBC cases. We reported that FA2H is a peroxisome proliferator-activated receptor α (PPARα)-regulated gene in human breast cancer MDA-MB-231 cells, in vitro experimental models for TNBC analysis. PPARα activation by its ligand reportedly results in an aggressive MDA-MB-231 cell phenotype, as well as estrogen receptor α (ERα)-positive MCF-7 cells. The results of this study show that i) MDA-MB-231 cells express very low levels of FA2H compared to the MCF-7 cells, reflecting a low basal-level PPARα-driven transcriptional activity compared to the MCF-7 cells, and ii) the increased FA2H expression stimulates the MDA-MB-231 and MCF-7 breast cancer cell migration without affecting proliferation. Taken together, our findings indicate that FA2H might be a breast cancer cell migration stimulator, independently of the ERα expression status.


Assuntos
Neoplasias da Mama/patologia , Movimento Celular , Oxigenases de Função Mista/metabolismo , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Feminino , Humanos , Oxigenases de Função Mista/genética , Mutação/genética
6.
J Biol Chem ; 292(25): 10586-10599, 2017 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-28487374

RESUMO

Dioxin and related chemicals alter the expression of a number of genes by activating the aryl hydrocarbon receptors (AHR) to produce a variety of disorders including hepatotoxicity. However, it remains largely unknown how these changes in gene expression are linked to toxicity. To address this issue, we initially examined the effect of 2,3,7,8-tetrachrolodibenzo-p-dioxin (TCDD), a most toxic dioxin, on the hepatic and serum metabolome in male pubertal rats and found that TCDD causes many changes in the level of fatty acids, bile acids, amino acids, and their metabolites. Among these findings was the discovery that TCDD increases the content of leukotriene B4 (LTB4), an inducer of inflammation due to the activation of leukocytes, in the liver of rats and mice. Further analyses suggested that an increase in LTB4 comes from a dual mechanism consisting of an induction of arachidonate lipoxygenase-5, a rate-limiting enzyme in LTB4 synthesis, and the down-regulation of LTC4 synthase, an enzyme that converts LTA4 to LTC4. The above changes required AHR activation, because the same was not observed in AHR knock-out rats. In agreement with LTB4 accumulation, TCDD caused the marked infiltration of neutrophils into the liver. However, deleting LTB4 receptors (BLT1) blocked this effect. A TCDD-produced increase in the mRNA expression of inflammatory markers, including tumor-necrosis factor and hepatic damage, was also suppressed in BLT1-null mice. The above observations focusing on metabolomic changes provide novel evidence that TCDD accumulates LTB4 in the liver by an AHR-dependent induction of LTB4 biosynthesis to cause hepatotoxicity through neutrophil activation.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Dioxinas/toxicidade , Leucotrieno B4/biossíntese , Infiltração de Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Dibenzodioxinas Policloradas/toxicidade , Receptores de Hidrocarboneto Arílico/metabolismo , Animais , Doença Hepática Induzida por Substâncias e Drogas/genética , Doença Hepática Induzida por Substâncias e Drogas/patologia , Leucotrieno B4/genética , Ativação de Neutrófilo/efeitos dos fármacos , Infiltração de Neutrófilos/genética , Neutrófilos/patologia , Ratos , Ratos Mutantes , Receptores de Hidrocarboneto Arílico/genética , Receptores do Leucotrieno B4/genética , Receptores do Leucotrieno B4/metabolismo
7.
Drug Chem Toxicol ; 41(4): 492-500, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29156995

RESUMO

We have conducted animal toxicity tests of chemicals for a chemical safety program implemented by the Ministry of Economy, Trade and Industry of Japan. Here we conducted a combined repeated-dose and reproductive/developmental toxicity screening test of benzene, 1,1'-oxybis-, tetrapropylene derivs. (BOTD). BOTD was administered to 9-week-old Crl:CD(SD) male and female rats by gavage at 0, 40, 200, or 1000 mg/kg/day. Males were treated for 42 days including mating period. Females were treated for 42-53 days through the premating, mating, pregnancy, and until Day 4 of lactation periods. Increases in prothrombin time and activated partial thromboplastin time values were observed only in males at 200 and 1000 mg/kg/day. Hypertrophy of centrilobular hepatocytes was observed with increased liver weight in both sexes at 200 and 1000 mg/kg/day, but there was no histologic evidence of hepatotoxicity. Diffuse hypertrophy of follicular cells in thyroid glands was observed in females at 200 mg/kg/day and in both sexes at 1000 mg/kg/day, with an increased blood cholesterol level in females at 1000 mg/kg/day. The conception index was decreased for females at 1000 mg/kg/day; and no abnormalities were detected in the reproductive indices of implantation, delivery, or pups' condition, although a slight increase in the pups' body weight was noted at birth. Our data indicate a no-observed-adverse-effect level of 40 mg/kg/day for repeated-dose toxicity on the basis of the prolongation of blood coagulating time, and of 200 mg/kg/day for reproductive/developmental toxicity on the basis of the decreased conception index.


Assuntos
Benzeno/toxicidade , Reprodução/efeitos dos fármacos , Animais , Coagulação Sanguínea/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ingestão de Alimentos/efeitos dos fármacos , Feminino , Fígado/efeitos dos fármacos , Masculino , Ratos , Ratos Sprague-Dawley
8.
J Biol Chem ; 291(48): 25255-25263, 2016 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-27765815

RESUMO

Alcoholic liver disease is a pathological condition caused by overconsumption of alcohol. Because of the high morbidity and mortality associated with this disease, there remains a need to elucidate the molecular mechanisms underlying its etiology and to develop new treatments. Because peroxisome proliferator-activated receptor-ß/δ (PPARß/δ) modulates ethanol-induced hepatic effects, the present study examined alterations in gene expression that may contribute to this disease. Chronic ethanol treatment causes increased hepatic CYP2B10 expression inPparß/δ+/+ mice but not in Pparß/δ-/- mice. Nuclear and cytosolic localization of the constitutive androstane receptor (CAR), a transcription factor known to regulate Cyp2b10 expression, was not different between genotypes. PPARγ co-activator 1α, a co-activator of both CAR and PPARß/δ, was up-regulated in Pparß/δ+/+ liver following ethanol exposure, but not in Pparß/δ-/- liver. Functional mapping of the Cyp2b10 promoter and ChIP assays revealed that PPARß/δ-dependent modulation of SP1 promoter occupancy up-regulated Cyp2b10 expression in response to ethanol. These results suggest that PPARß/δ regulates Cyp2b10 expression indirectly by modulating SP1 and PPARγ co-activator 1α expression and/or activity independent of CAR activity. Ligand activation of PPARß/δ attenuates ethanol-induced Cyp2b10 expression in Pparß/δ+/+ liver but not in Pparß/δ-/- liver. Strikingly, Cyp2b10 suppression by ligand activation of PPARß/δ following ethanol treatment occurred in hepatocytes and was mediated by paracrine signaling from Kupffer cells. Combined, results from the present study demonstrate a novel regulatory role of PPARß/δ in modulating CYP2B10 that may contribute to the etiology of alcoholic liver disease.


Assuntos
Hidrocarboneto de Aril Hidroxilases/biossíntese , Família 2 do Citocromo P450/biossíntese , Regulação Enzimológica da Expressão Gênica , Hepatopatias Alcoólicas/metabolismo , Fígado/metabolismo , PPAR delta/metabolismo , PPAR beta/metabolismo , Regiões Promotoras Genéticas , Fator de Transcrição Sp1/metabolismo , Esteroide Hidroxilases/biossíntese , Animais , Hidrocarboneto de Aril Hidroxilases/genética , Família 2 do Citocromo P450/genética , Etanol/toxicidade , Hepatócitos/metabolismo , Hepatócitos/patologia , Células de Kupffer/metabolismo , Células de Kupffer/patologia , Fígado/patologia , Hepatopatias Alcoólicas/genética , Hepatopatias Alcoólicas/patologia , Camundongos , Camundongos Knockout , PPAR delta/genética , PPAR beta/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Fator de Transcrição Sp1/genética , Esteroide Hidroxilases/genética
9.
Ann Nutr Metab ; 71(1-2): 10-15, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28647743

RESUMO

BACKGROUND/AIMS: The ability to readily diagnose sarcopenia and malnutrition in a clinical setting is essential. This study is aimed at clarifying the calf circumference (CC) cut-off values for decreased skeletal muscle mass (SMM), according to the Asian Work Group for Sarcopenia's criteria definition of sarcopenia, and those for European Society for Clinical Nutrition and Metabolism-defined malnutrition, in hospitalized Japanese patients. METHODS: The study involved 1,164 patients aged ≥65 years. Predictive CC cut-off values were determined using receiver operating curve (ROC) analyses. The predictive validity of the cut-off values was confirmed against in-hospital mortality. RESULTS: There were 654 females and 510 males (mean age, 83.5 ± 8.2 years). Decreased SMM and malnutrition were observed in 80.4 and 32.8% of all patients, respectively. ROC analyses identified CCs of ≤29 cm (female, area under the curve [AUC] 0.791) and ≤30 cm (male, AUC 0.832) as cut-off values for decreased SMM, and CCs of ≤26 cm (female, AUC 0.798) and ≤28 cm (male, AUC 0.837) for malnutrition. CC cut-off values for SMM and malnutrition were independently correlated with in-hospital mortality. CONCLUSIONS: The study determined appropriate cut-off values for CC to identify decreased SMM and malnutrition according to the relevant guidelines.


Assuntos
Desnutrição/diagnóstico , Músculo Esquelético/anatomia & histologia , Sarcopenia/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Antropometria , Índice de Massa Corporal , Estudos Transversais , Europa (Continente) , Feminino , Mortalidade Hospitalar , Hospitalização , Humanos , Masculino , Desnutrição/etiologia , Tamanho do Órgão , Estudos Retrospectivos , Sarcopenia/complicações
10.
Drug Chem Toxicol ; 40(3): 344-358, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27790921

RESUMO

We have carried out animal toxicity tests of chemicals for a chemical safety program implemented by the Ministry of Economy, Trade, and Industry of Japan. Here, we tested 1-tert-butoxy-4-chlorobenzene in a combined repeat-dose and developmental and reproductive toxicity test. The test chemical was administered daily by gavage to 9-week-old Crl:CD (SD) rats at doses of 0, 20, 100, and 500 mg/kg/d. Males were treated for 42 d beginning 14 d before mating. Females were treated from 14 d before mating to day 4 of lactation. Decreased spontaneous locomotion, decreased respiratory rate, and incomplete eyelid opening were observed at 500 mg/kg/d (both sexes), but resolved within 30 min of administration, suggesting central nervous system depression. No notable changes were observed in body weight, food consumption, functional battery tests, or blood test. Increased liver weight with centrilobular or diffuse hepatocyte hypertrophy was observed at 100 and 500 mg/kg/d (both sexes). There were no biochemical or histopathological changes related to hepatotoxicity. Increased kidney weight with basophilic tubules, tubule dilatation, and increased hyaline droplets were observed in males dosed at 100 and 500 mg/kg/d. Immunohistochemical staining indicated α2u-globulin nephropathy, a male rat-specific toxicity. Although kidney weight was also increased in females dosed at 500 mg/kg/d, it was not considered to be an adverse effect because there were no histopathological changes. Pup weights on postnatal day 0 were decreased at 500 mg/kg/d and still decreased on postnatal day 4. Our data indicated the no-observed-adverse-effect-level for repeated-dose and reproductive/developmental toxicity for 1-tert-butoxy-4-chlorobenzene was 100 mg/kg/d.


Assuntos
Clorobenzenos/toxicidade , Exposição Materna/efeitos adversos , Exposição Paterna/efeitos adversos , Éteres Fenílicos/toxicidade , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Reprodução/efeitos dos fármacos , Administração Oral , Animais , Animais Recém-Nascidos , Peso Corporal/efeitos dos fármacos , Clorobenzenos/administração & dosagem , Relação Dose-Resposta a Droga , Ingestão de Alimentos/efeitos dos fármacos , Feminino , Masculino , Nível de Efeito Adverso não Observado , Tamanho do Órgão/efeitos dos fármacos , Especificidade de Órgãos , Éteres Fenílicos/administração & dosagem , Gravidez , Ratos Sprague-Dawley , Testes de Toxicidade
11.
Asian Pac J Allergy Immunol ; 34(4): 314-323, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27543726

RESUMO

BACKGROUND: MF59, which is an adjuvant belonging to C30 member of the terpene family, is a T helper type-2 (Th2)-biased immune enhancer. Our previous studies showed that pyriproxyfen, a member of the terpene family with fewer carbon atoms (C20) than MF59, enhanced active T helper type-1 (Th1)-biased immune responses. OBJECTIVE: This study was performed to investigate the enhancement of antigen-specific immune responses by myrcene, a member of the terpene family with fewer carbon atoms (C10) than pyriproxyfen. METHOD: Ovalbumin (OVA) was used as an antigen to determine the effects of myrcene on the immune response. The IgG subtypes and cytokines induced by immunization of OVA with or without myrcene were monitored. Thereafter, we determined the effects of myrcene in the immune response against Ag85B, which is a dominant protective antigen for tuberculosis. RESULTS: The results showed that 0.8 mg/dose of myrcene enhanced antigen-specific total IgG immune response to OVA. Direct mixing of the antigen with myrcene was required for the enhancement of antibody production. Myrcene increased OVA-specific IgG2a titer, suggesting induction of Th1-immune response. The level of Th1 cytokines, IFN-γ was increased at 8 weeks after immunization, although IL-13 was also increased at the same time point. However, finally myrcene was found to increase Ag85B-specific total IgG titers at 5 weeks and specific IgG2a titer was increased at both 5 and 8 weeks. The results suggested that myrcene could enhance Th1 immune response. CONCLUSIONS: Myrcene enhanced specific immune responses against OVA and Ag85B. This study suggested the tendency of the enhancement of Th1 immune response by myrcene.


Assuntos
Adjuvantes Imunológicos/farmacologia , Alcenos/farmacologia , Formação de Anticorpos/efeitos dos fármacos , Monoterpenos/farmacologia , Monoterpenos Acíclicos , Aciltransferases/imunologia , Animais , Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Imunoglobulina G , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/imunologia , Células Th1/imunologia
12.
Drug Chem Toxicol ; 38(4): 361-74, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25367778

RESUMO

4-Methoxy-2-nitroaniline (4M2NA) is widely used as an intermediate for the synthesis of dyes, pigments and other chemical compounds. Since 4M2NA has amino-group and nitro-group on the benzene ring, it was expected that it induced obvious hemolytic anemia. We conducted a combined repeated dose and reproductive/developmental toxicity screening test according to Organisation for Economic Co-operation and Development (OECD) Test Guideline No. 422 (OECD TG 422) to enrich the toxic information and ensure the safety of 4M2NA. 4M2NA was administered to Crl:CD(SD) male and female rats by gavage at 0, 12.5, 75 or 450 mg/kg/day for 42 to maximum of 54 days through pre-mating, mating, pregnancy and lactation periods. An extramedullary hematopoiesis and congestion in spleen, and higher reticulocyte ratio were noted in only females at 450 mg/kg/day without decreased anemic parameters in the hematological examination. Hypertrophy of centrilobular hepatocytes in both sexes was observed with increased relative liver weight at 450 mg/kg/day. Furthermore, the diffuse follicular cell hypertrophy of the thyroid was observed in females at 450 mg/kg/day. No abnormalities were detected in the reproductive indices of copulation, delivery or fetal viability. We concluded the no-observed-adverse-effect level (NOAEL) for repeated-dose toxicity was 75 mg/kg/day based on the trace evidences of hemolytic anemia, and the NOAEL for reproductive/developmental toxicity as 450 mg/kg/day based on no toxicological concerns for reproductive endpoints. The hemolytic anemia was much milder than expected. Thus, we discussed the reason of this much less hemolytic effect from the point of view of the structural characteristics of 4M2NA.


Assuntos
Anemia Hemolítica/induzido quimicamente , Compostos de Anilina/toxicidade , Reprodução/efeitos dos fármacos , Compostos de Anilina/administração & dosagem , Animais , Relação Dose-Resposta a Droga , Feminino , Hepatócitos/efeitos dos fármacos , Hepatócitos/patologia , Lactação , Masculino , Nível de Efeito Adverso não Observado , Tamanho do Órgão/efeitos dos fármacos , Gravidez , Ratos , Ratos Sprague-Dawley , Reticulócitos/efeitos dos fármacos , Reticulócitos/metabolismo , Fatores Sexuais , Baço/efeitos dos fármacos , Baço/patologia , Testes de Toxicidade
13.
Drug Chem Toxicol ; 37(3): 303-10, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24252074

RESUMO

A subchronic (180-day) toxicity study was conducted to evaluate the effects of ethyl tertiary-butyl ether (ETBE), a biomass fuel, in male and female rats. ETBE was administered at dose levels of 0, 5, 25, 100 and 400 mg/kg/body weight (b.w.)/day by gavage. No treatment-related adverse effects were observed at 5, 25 or 100 mg/kg. Centrilobular hypertrophy of hepatocytes was observed in males and females and their relative liver weights were increased, suggesting enhanced metabolic activity. From these results, we concluded that the no observed adverse effect level of ETBE was 100 mg/kg b.w./day under the conditions tested.


Assuntos
Biomassa , Etil-Éteres/toxicidade , Hepatócitos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Etil-Éteres/administração & dosagem , Feminino , Hepatócitos/metabolismo , Fígado/metabolismo , Masculino , Nível de Efeito Adverso não Observado , Tamanho do Órgão , Ratos , Ratos Sprague-Dawley , Testes de Toxicidade Subcrônica
14.
Nanomaterials (Basel) ; 14(3)2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38334557

RESUMO

Research in the field of high-intensity focused ultrasound (HIFU) for intracranial gene therapy has greatly progressed over the years. However, limitations of conventional HIFU still remain. That is, genes are required to cross the blood-brain barrier (BBB) in order to reach the neurological disordered lesion. In this study, we introduce a novel direct intracranial gene delivery method, bypassing the BBB using human serum albumin-based nanobubbles (NBs) injected through a less invasive intrathecal route via lumbar puncture, followed by intracranial irradiation with low-frequency ultrasound (LoFreqUS). Focusing on both plasmid DNA (pDNA) and messenger RNA (mRNA), our approach utilizes LoFreqUS for deeper tissue acoustic penetration and enhancing gene transfer efficiency. This drug delivery method could be dubbed as the "Spinal Back-Door Approach", an alternative to the "front door" BBB opening method. Experiments showed that NBs effectively responded to LoFreqUS, significantly improving gene transfer in vitro using U-87 MG cell lines. In vivo experiments in mice demonstrated significantly increased gene expression with pDNA; however, we were unable to obtain conclusive results using mRNA. This novel technique, combining albumin-based NBs and LoFreqUS offers a promising, efficient, targeted, and non-invasive solution for central nervous system gene therapy, potentially transforming the treatment landscape for neurological disorders.

15.
Biochem Pharmacol ; 210: 115490, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36893816

RESUMO

Maternal exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) causes developmental and reproductive disorders in pups due to the attenuated luteinizing hormone (LH) production during the perinatal stage; however, the administration of α-lipoic acid (LA) to TCDD-exposed pregnant rats reversed the attenuated LH production. Therefore, reproductive disorders in pups are expected to be ameliorated with LA supplementation. To address this issue, pregnant rats orally received low dose TCDD at gestational day 15 (GD15) and proceeded to parturition. The control received a corn oil vehicle. To examine the preventive effects of LA, supplementation with LA was provided until postnatal day 21. In this study, we demonstrated that maternal administration of LA restored the sexually dimorphic behavior of male and female offspring. TCDD-induced LA insufficiency is likely a direct cause of TCDD reproductive toxicity. In the analysis to clarify the mechanism of the decrease in LA, we found evidence suggesting that TCDD inhibits the synthesis and increases the utilization of S-adenosylmethionine (SAM), a cofactor for LA synthesis, resulting in a decrease in the SAM level. Furthermore, folate metabolism, which is involved in SAM synthesis, is disrupted by TCDD, which may adversely affect infant growth. Maternal supplementation of LA restored SAM to its original level in the fetal hypothalamus; in turn, SAM ameliorated abnormal folate consumption and suppressed aryl hydrocarbon receptor activation induced by TCDD. The study demonstrates that the application of LA could prevent and recover next-generation dioxin reproductive toxicity, which provides the potential to establish effective protective measures against dioxin toxicity.


Assuntos
Ácido Fólico , Exposição Materna , Dibenzodioxinas Policloradas , Efeitos Tardios da Exposição Pré-Natal , Caracteres Sexuais , Desenvolvimento Sexual , Ácido Tióctico , Animais , Feminino , Masculino , Gravidez , Ratos , Feto/efeitos dos fármacos , Feto/metabolismo , Ácido Fólico/metabolismo , Hipotálamo/efeitos dos fármacos , Hipotálamo/metabolismo , Exposição Materna/efeitos adversos , Dibenzodioxinas Policloradas/toxicidade , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Efeitos Tardios da Exposição Pré-Natal/prevenção & controle , S-Adenosilmetionina/metabolismo , Desenvolvimento Sexual/efeitos dos fármacos , Ácido Tióctico/administração & dosagem , Ácido Tióctico/farmacologia , Ácido Tióctico/uso terapêutico , Reprodução/efeitos dos fármacos
16.
Front Pharmacol ; 14: 1167934, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37251332

RESUMO

Hachimijiogan (HJG) has originally been used to ameliorate a variety of symptoms associated with low ambient temperatures. However, its pharmacological action in metabolic organs remains unclear. We hypothesized that HJG may modulate metabolic function and have a potential therapeutic application to metabolic diseases. To test this hypothesis, we investigated metabolic action of HJG in mice. Male C57BL/6J mice chronically administered with HJG showed a reduction in adipocyte size with increased transcription of beige adipocyte-related genes in subcutaneous white adipose tissue. HJG-mixed high-fat diet (HFD)-fed mice showed alleviation of HFD-induced weight gain, adipocyte hypertrophy, liver steatosis with a significant reduction in circulating leptin and Fibroblast growth factor 21 despite no changes in food intake or oxygen consumption. Feeding an HJG-mixed HFD following 4-weeks of HFD feeding, while a limited effect on body weight, improved insulin sensitivity with a reversal of decreased circulating adiponectin. In addition, HJG improved insulin sensitivity in the leptin-deficient mice without significant effects on body weight. Treatment with n-butanol soluble extracts of HJG potentiated transcription of Uncoupling protein 1 mediated by ß3-adrenergic agonism in 3T3L1 adipocytes. These findings provide evidence that HJG modulates adipocyte function and may exert preventive or therapeutic effects against obesity and insulin resistance.

17.
J Toxicol Sci ; 47(4): 159-168, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35370244

RESUMO

Detailed in vitro studies on the effects of perfluorooctanoic acid (PFOA) have demonstrated that activation of peroxisome proliferator-activated receptor α (PPARα) is a key process by which PFOA affects the malignancy of estrogen receptor α (ERα)-positive breast cancer cells. However, there is very little information on the PPARα-regulated genes responsible for the effects of PFOA in ERα-negative breast cancer cell malignancy. We recently demonstrated that fatty acid 2-hydroxylase (FA2H) stimulates the migration of ERα-negative human MDA-MB-231 cells, and PPARα is a key factor for the induction of FA2H in these cells. However, evidence for the relationship between PFOA exposure and PPARα-FA2H axis-driven migration has not been obtained. Here we analyzed the effects of PFOA on PPARα transcription and FA2H expression in relation to MDA-MB-231 cell migration. We found that simultaneously with stimulated migration, PFOA upregulated FA2H and activated the transcription of PPARα. FA2H-selective siRNA, but not siRNA control, clearly dampened PFOA-mediated cell migration. There is an inhibitory interaction between PPARα and PPARß/δ (i.e., PPARß/δ can suppress PPARα-mediated transcription) in MDA-MB-231 cells, but even in the presence of PPARß/δ expression, PFOA appeared to free PPARα to upregulate FA2H. Collectively, our findings show that i) PFOA activates PPARα-mediated transcription, ii) PFOA stimulates migration dependent on FA2H expression, and iii) mechanistically, PFOA relieves PPARß/δ suppression of PPARα activity to upregulate FA2H in MDA-MB-231 cells.


Assuntos
Receptores de Estrogênio , Neoplasias de Mama Triplo Negativas , Caprilatos/toxicidade , Movimento Celular , Fluorocarbonos , Humanos , Oxigenases de Função Mista/genética
18.
Fukuoka Igaku Zasshi ; 102(4): 159-66, 2011 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-21706896

RESUMO

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) exposed to pregnant or lactational mother impairs the reproduction and development of the pups. The defect is a serious problem, because it is caused by TCDD at much lower doses than that needed for acute toxicity in the mother. However, the toxic mechanism underlying the defect remains to be obscure. We have previously revealed that maternal exposure to TCDD (1 microg/kg) causes a reduction in luteinizing hormone in the fetal pituitary, leading to the reduced expression of testicular steroidogenic proteins such as steroidogenic acute-regulatory protein (StAR) and cytochrome P450 (CYP) 17. In addition, we have provided evidence that such a reduction imprints defects in sexual behaviors at adulthood. In this study, we investigated TCDD effect on fetal steroidogenesis in the extra-gonadal tissues. Even when pregnant Wistar rats at gestational day (GD) 15 were orally treated with TCDD (0.25, 1 or 3 microg/kg), neither expression of StAR nor CYP17 mRNA was affected in the adrenal gland, placenta and hypothalamus of male fetuses (GD20). However, TCDD induced placental StAR (3 microg/kg) and adrenal CYP17 mRNAs (0.25 microg/kg) in female fetuses. Therefore, our study suggests that while TCDD gives damage to male fetal steroidogenesis in a testis-specific manner, the dioxin enhances the steroidogenesis of the fetal adrenal gland and placenta in females. Thus, the mechanism whereby TCDD exerts its endocrine-disrupting properties is considered to differ, at least partially, between male and female fetuses.


Assuntos
Glândulas Suprarrenais/metabolismo , Feto/metabolismo , Exposição Materna , Placenta/metabolismo , Dibenzodioxinas Policloradas/intoxicação , Esteroides/biossíntese , Animais , Feminino , Masculino , Fosfoproteínas/metabolismo , Gravidez , Ratos , Ratos Wistar , Fatores Sexuais , Esteroide 17-alfa-Hidroxilase/metabolismo
19.
Sci Rep ; 11(1): 204, 2021 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-33420316

RESUMO

Hand choices-deciding which hand to use to reach for targets-represent continuous, daily, unconscious decisions. The posterior parietal cortex (PPC) contralateral to the selected hand is activated during a hand-choice task, and disruption of left PPC activity with a single-pulse transcranial magnetic stimulation prior to the execution of the motion suppresses the choice to use the right hand but not vice versa. These findings imply the involvement of either bilateral or left PPC in hand choice. To determine whether the effects of PPC's activity are essential and/or symmetrical in hand choice, we increased or decreased PPC excitability in 16 healthy participants using transcranial direct current stimulation (tDCS; 10 min, 2 mA, 5 × 7 cm) and examined its online and residual effects on hand-choice probability and reaction time. After the right PPC was stimulated with an anode and the left PPC with a cathode, the probability of left-hand choice significantly increased and reaction time significantly decreased. However, no significant changes were observed with the stimulation of the right PPC with a cathode and the left PPC with an anode. These findings, thus, reveal the asymmetry of PPC-mediated regulation in hand choice.


Assuntos
Comportamento de Escolha , Lateralidade Funcional/fisiologia , Mãos/fisiologia , Lobo Parietal/fisiologia , Estimulação Transcraniana por Corrente Contínua , Adulto , Feminino , Humanos , Masculino
20.
Low Urin Tract Symptoms ; 13(3): 400-409, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33648020

RESUMO

OBJECTIVES: An enriched environment (EE) has been known to promote structural changes in the brain and enhance learning and emotional performance. However, little is known about the effect of an EE on brain stem functions, such as the micturition function. In this study, we examined whether an EE affects micturition activity in mice. METHODS: Male C57BL/6J mice were used. We assessed the micturition activity of freely moving mice using a novel system developed in-house. RESULTS: During the dark period, but not light, the EE significantly increased voiding frequency, total voided volume, mean voided volume, voiding duration, mean flow rate, and maximum flow rate compared with the control environment. This EE effect on micturition function was associated with habituation to novel environments in the open-field test, but not with amelioration of motor coordination in the rotarod test. Interestingly, even after the mice were withdrawn from the EE, the improvements in micturition function persisted, while other behavioral changes were abolished. The relative value of voiding frequency and total voided volume during the light period, expressed as a percentage of 24 hours, increased with age when mice were reared in a standard environment. However, this age-related change was not observed in mice reared in an EE. CONCLUSIONS: These results suggest that an EE may promote micturition activity during the active phase of C57BL/6J mice, and its effects persist even after withdrawal from the EE. Furthermore, an EE may mitigate dysfunctions in micturition activity, such as polyuria, during the resting phase in aged mice.


Assuntos
Poliúria , Micção , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL
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