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The antiallergic effects of gut microbiota have been attracting attention in recent years, but the underlying cellular and molecular mechanisms have not yet been fully understood. In this study, we aimed to investigate these mechanisms specifically focusing on mast cells. Mast cells retain intracellular granules containing various inflammatory mediators such as histamine, which are released outside the cells upon IgE and allergen stimulation. We previously reported that increased expression of the transcription factor, CCAAT/enhancer-binding protein α (C/EBPα), suppresses granule formation in mast cells and that Lacticaseibacillus casei JCM1134T (LC) upregulates C/EBPα levels. Here, granule formation in mouse bone marrow-derived mast cells was suppressed in a MyD88-dependent manner after LC treatment due to C/EBPα-dependent downregulation of the genes encoding serglycin (SRGN) and mast cell protease 4 (Mcpt4). Furthermore, C/EBPα expression was regulated by DNA methylation in the 5' region far upstream of the transcription start site. LC suppressed DNA methylation of specific CpG motifs in the 5' region of the C/EBPα gene. These results conclude that specific gut microbial components, such as those from LC, suppress granule formation in mast cells by inhibiting SRGN and Mcpt4 expression via reduced C/EBPα gene methylation.
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This study aimed to investigate the effect of diagnosis and treatment of chronic endometritis (CE) on the outcome of assisted reproductive technology (ART) with or without repeated implantation failure (RIF). This retrospective analysis included patients who underwent pathological examination for diagnosis of CE at Yamagata University Hospital. The examination was performed for all patients planned for ART with or without RIF. Patients who were examined within 6 months of the first oocyte retrieval or embryo transfer were included. We counted the number of CD138-positive cells within the endometrial stroma in patients' specimens and analyzed the patients' clinical information. Clinical rates of pregnancy and implantation were determined. A total of 80 women met the inclusion criteria: 13 CE-negative patients (17.3%) and 67 CE-positive patients (83.7%). A significant decrease was noted in the CD138-positive cell count between the first biopsy and second biopsy after CE treatment (p < 0.001). In addition, no significant differences were noted in ongoing pregnancy rates between the CE-negative patients and those who underwent CE treatment. The CD138-positive cell counts at first biopsy tended to be lower in each pregnancy group than in the non-pregnancy group. For patients planned to undergo ART, examination for diagnosis of CE with or without RIF could be considered. Pathological CD138-positive cell counts were considered useful for CE diagnosis and treatment decision-making. The study findings suggest the efficacy of antimicrobial agents in CE treatment, contributing to improved pregnancy outcomes.
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The intestinal microbiota is involved in many diseases, such as constipation, obesity, and inflammatory bowel disease. To determine the associations between the gut microbiome and the frequency of bowel movements, we performed cross-sectional correlation analysis at the baseline and longitudinal correlation analysis after the intervention. Forty-three women were enrolled in this study. All participants ingested soymilk-okara powder (15 g) daily for 12 weeks. They recorded the ingested okara powder amounts and their frequency of bowel movements during the entire 12 weeks of the intervention. The fecal microbiota percentages were measured at baseline and after 12 weeks of intervention. Two women who did not completely record the frequency of bowel movements were excluded. In the cross-sectional correlation analysis at the baseline, there was a significant positive correlation between the relative abundance of the Bacteroides genus in the feces and the frequency of bowel movements per week (R = 0.429, p = 0.005) and a significant negative correlation between the relative abundance of Clostridium cluster XI in the feces and the frequency of bowel movements per week (R = -0.315, p = 0.045). Moreover, in the longitudinal correlation analysis, the difference in the relative abundance of Bacteroides genus in feces between the baseline and after the intervention significantly correlated with the changes in the frequency of bowel movements per week (R = 0.492, p = 0.001). Therefore, it was suggested that there was a relationship between the gut relative abundance of the Bacteroides genus and the frequency of bowel movements.
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Bacteroides , Defecação , Fezes , Microbioma Gastrointestinal , Humanos , Feminino , Fezes/microbiologia , Bacteroides/isolamento & purificação , Estudos Transversais , Pessoa de Meia-Idade , Adulto , Japão , Alimentos de Soja/microbiologia , Constipação Intestinal/microbiologia , Estudos Longitudinais , População do Leste AsiáticoRESUMO
The frequency of twins resulting from a single embryo transfer has been reported to be 1.56%, with the majority being monochorionic. We present a case of septal rupture at 8 weeks of gestation and successful delivery at 36 weeks of gestation of a monozygotic dichorionic diamniotic twin after a single blastocyst transfer. This report could partially clarify the pathogenesis of monozygotic twins and septal disruption. A 37-year-old woman with 9 months of primary infertility was referred to our department. After seven cycles of artificial insemination, she underwent her first in vitro fertilization. Ten cumulous-oocyte complexes were retrieved, of which three were fertilized, and three blastocysts were cryopreserved. The first single blastocyst transfer in a hormone replacement cycle resulted in a dichorionic diamniotic twin pregnancy. Transvaginal ultrasound at 7 weeks and 4 days gestation revealed a size difference in the gestational sacs and a disruption of the inter-amniotic membrane between the two gestational sacs at 8 weeks and 6 days. Both fetuses were seen in the larger gestational sac; however, the umbilical cord of the migrated fetus was from the original gestational sac. Both fetuses developed without discordancy or obvious anomalies. At 36 weeks and 6 days of gestation, the patient underwent cesarean delivery, resulting in the birth of two viable male infants without any congenital anomalies (weighing 2256 g and 2456 g). Two amniotic cavities existed; however, no chorionic villi were present. There have been many reports on septal disruption in monochorionic diamniotic twins; however, only two cases of dichorionic diamniotic twins have been reported. Furthermore, the onsets in both reports were after the second trimester of pregnancy. This report presents the first case of septal disruption in dichorionic diamniotic twins during the first trimester.
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Gravidez de Gêmeos , Gêmeos Monozigóticos , Humanos , Gravidez , Feminino , Masculino , Adulto , Transferência Embrionária , Segundo Trimestre da Gravidez , Primeiro Trimestre da GravidezRESUMO
Background: The coronavirus disease 2019 (COVID-19) pandemic impacted various parts of society, including Japanese children with allergies. Objective: This study investigated risk factors for pediatric allergic diseases associated with the state of emergency owing to the COVID-19 pandemic in Japan, including during school closures. Methods: Parents of pediatric patients (0-15 years) with allergies were enrolled and queried regarding the impact of school closure on pediatric allergies compared to that before the COVID-19 pandemic. Results: A valid response was obtained from 2302 parents; 1740 of them had children with food allergies. Approximately 4% (62/1740) of the parents reported accidental food allergen ingestion was increased compared to that before the COVID-19 pandemic. Accidental ingestion during school closures was associated with increased contact with meals containing allergens meant for siblings or other members of the family at home. The exacerbation rate during the pandemic was highest for atopic dermatitis at 13% (127/976), followed by allergic rhinitis at 8% (58/697), and bronchial asthma at 4% (27/757). The main risk factors for worsening atopic dermatitis, allergic rhinitis, and bronchial asthma were contact dermatitis of the mask area (34/120 total comments); home allergens, such as mites, dogs, and cats (15/51 total comments); and seasonal changes (6/25 total comments), respectively. Conclusion: The main factors affecting allergic diseases were likely related to increased time at home, preventive measures against COVID-19, and refraining from doctor visits. Children with allergies were affected by changes in social conditions; however, some factors, such as preventing accidental ingestion and the management of allergens at home, were similar to those before the COVID-19 pandemic. Patients who had received instructions on allergen avoidance at home before the pandemic were able to manage their disease better even when their social conditions changed.
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INTRODUCTION: Oral immunotherapy (OIT) imposes a burden on parents and their children with food allergies (FAs). We already developed a questionnaire for OIT-related Parental Burden (OIT-PB) scale. However, the previous questionnaire had some problems. This study modified OIT-PB and verified its reliability and validity. METHODS: A 20-item draft covering the physical and mental burdens caused by OIT was prepared jointly with multiple allergists. The Food Allergy Quality of Life Questionnaire-Parental Burden (FAQLQ-PB) and Stress Response Scale-18 (SRS-18) were used to verify concurrent validity. A questionnaire survey was administered during treatment to parents of FA children who had started OIT for the first time. An additional OIT-PB survey was performed at one specific institution 1 week after the posttreatment survey. RESULTS: The responses of 64 of the 76 recruited parents were analyzed. Of the 20 questions, 1 item was excluded owing to the floor effect, 1 was excluded because its commonality was less than 0.2, and 2 were excluded because their factor loading values were less than 0.4. Factor analysis was used to classify the OIT-PB into the following 4 subscales: "burden caused by adherence to treatment plan," "anxiety about symptom-induced risk," "burden due to patient's eating behavior," and "anxiety about treatment effect." The Cronbach's α for all 16 items of the OIT-PB was 0.893; Cronbach's α for each subscale was 0.876, 0.898, 0.874, and 0.717. The re-test reliability coefficient was 0.864 (95% confidence interval [CI]: 0.720-0.937, p < 0.001). A significant positive correlation was found between the OIT-PB and FAQLQ-PB (R = 0.610 [95% CI: 0.422-0.747], p < 0.001) and the SRS-18 (R = 0.522 [95% CI: 0.306-0.687], p < 0.001). A significant negative correlation was found between the rate of increase in OIT food intake and the "anxiety about treatment effect" score (R = -0.355 [95% CI: -0.558-0.112], p < 0.001). Parents of children on the hen's egg OIT treatment scored higher on the "burden due to patient's eating behavior" subscale than did parents of children on the milk and wheat OIT treatment. CONCLUSION: The burden of OIT experienced by parents can be broadly classified into four categories. The modified OIT-PB was able to evaluate them individually and was shown to have reliability and validity. This scale is expected to be useful in the development of OIT that considers not only therapeutic effect but also the burden experienced by FA children and their parents.
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Hipersensibilidade Alimentar , Qualidade de Vida , Criança , Humanos , Feminino , Animais , Reprodutibilidade dos Testes , Galinhas , Hipersensibilidade Alimentar/terapia , Ovos , Imunoterapia , Pais , Alérgenos , Administração Oral , Dessensibilização ImunológicaRESUMO
Anxiety in parents of children with allergic diseases during the COVID-19 pandemic may impact hospital visits. This study explored the effect of the pandemic on parents' fears about hospital visits and their relationship with their personality traits. A cross-sectional, questionnaire-based study was conducted between September 2020 and March 2021, with parents of children aged 0-15 years, who regularly visited 24 outpatient facilities for allergic disease. The survey included patient information, fears about hospital visits, desired information, and the State-Trait Anxiety Inventory. Responses were compared between parents with high and low trait anxiety. The response rate was 97.6% (2439/2500). The most common fear was "Fear of getting medical care as usual (85.2%)" and "Fear of COVID-19 infection during hospital visits (87.1%)". High trait anxiety showed a significant association with "Fear of worsening of children's allergies" (adjusted OR: 1.31, 95%CI: 1.04 to 1.65, p = 0.022), and "Fear of worsening of COVID-19 due to allergy" (adjusted OR: 1.52, 95%CI: 1.27 to 1.80, p < 0.01). Healthcare professionals should share updates on COVID-19 and healthcare system to reduce parents' fear. Subsequently, they should communicate the importance of continuing treatment to prevent worsening of COVID-19 and avoid emergency visits, considering parental trait anxiety.
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COVID-19 is an ongoing worldwide pandemic. Even today, there is a need for the development of effective therapeutic agents. SARS-CoV-2 is known as the causative virus of COVID-19, and its main protease is one of the enzymes essential for its growth and is considered a drug discovery target. In this study, we evaluated the inhibitory activities of a variety of fullerene derivatives, including newly synthesized derivatives, against the main protease of SARS-CoV-2. As a result, the malonic acid-type fullerene derivatives showed the strongest inhibitory activity.
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COVID-19 , Fulerenos , Humanos , SARS-CoV-2 , Fulerenos/farmacologia , Inibidores de Proteases/farmacologia , Antivirais/farmacologia , Proteases 3C de Coronavírus , Simulação de Acoplamento MolecularRESUMO
Okara is a by-product of soymilk manufacturing and a rich source of protein and dietary fiber. This study investigates whether dietary soymilk-okara powder intake in the long term affects the body composition and gut microbiota flora in healthy Japanese adults. In total, 46 subjects (43 women) were enrolled. All subjects ingested 15 g of soymilk-okara powder every day for 12 weeks. Subjects' body composition was assessed over four weeks. At baseline and after intervention for 12 weeks, fecal short-chain fatty acid concentrations and microbiota percentages were measured. The body muscle weight significantly increased, and the percentage of body fat significantly decreased at 4, 8, and 12 weeks after the intervention. The increase in body muscle after 12 weeks was 0.6 kg (interquartile range:-0.03 to 1.0). The decrease in body fat was -0.9% (interquartile range: -1.6 to -0.2). There was a significant negative correlation between the changes in body fat and body muscle. For the fecal percentages of Coriobacteriaceae, Lactobacillales, Bacteroides, Clostridium cluster IV, and Clostridium cluster XI, there were significant differences between the baseline and 12 weeks after the intervention. Furthermore, there were significant negative correlations between the changes in body fat percentage and fecal acetic acid and propionic acid levels. Therefore, a dietary intake of 15 g of soymilk-okara powder for 12 weeks induced a decrease in body fat, an increase in body muscle, and a change in fecal microbiota flora. Soymilk-okara powder is effective in improving body composition and changing the intestinal microbiota flora in healthy Japanese adults.
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Tecido Adiposo , Fibras na Dieta , População do Leste Asiático , Músculos , Leite de Soja , Humanos , Pós , Composição Corporal , Microbiota , Masculino , FemininoRESUMO
The intestine is inhabited by a large number of commensal bacteria that are immunologically non-self, potentially causing inflammation. However, in a healthy intestine, inflammation is strictly controlled at low levels to maintain homeostasis. We previously reported that the gut microbiota induce DNA methylation of the gene encoding Toll-like receptor (TLR) 4, a pattern recognition receptor that recognizes lipopolysaccharides of gram-negative bacteria, in colonic epithelial cells, suggesting its role in controlling intestinal inflammation. However, there remains a question of how gut microbiota cause methylation of only specific genes including TLR4, despite the fact that DNA methyltransferase (DNMT) is common to all genes targeted for methylation. Here, we identified RBM14 as an adaptor molecule that recruits DNMT to the TLR4 gene. RBM14 was shown to bind DNMT3 and be expressed at significantly higher levels in an intestinal epithelial cell (IEC) line with hypermethylated TLR4 gene than in an IEC line with hypomethylated TLR4 gene. In addition, RBM14 interacted with DNA regions of the TLR4 gene, and knockdown of RBM14 suppressed DNA methylation of the TLR4 gene in IECs. Furthermore, RBM14 expression was higher in colonic epithelial cells of conventional mice than in those of germ-free mice. Collectively, these results indicate that the gut microbiota induce methylation of the TLR4 gene in colonic epithelial cells by upregulating RBM14, which can recruit DNMT3 to the gene. The regulation of adaptor molecules such as RBM14, which bind to specific target genes and recruit DNMT, can explain, at least in part, how gut microbiota contribute to the maintenance of intestinal homeostasis through epigenetic control of specific gene expression in IECs.
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Apoptotic cell death is a critical step in organism development and tissue homeostasis. Apoptotic cells affect immune cell activities in normal tissues. It is not clear whether similar cell death machinery causes tumor environments to evade anti-tumor immune responses. Here, using a mouse transplant model, we found a large number of tumor cells undergoing intrinsic apoptosis in tumors derived from the 4T1 breast cancer cell line, where neutrophils significantly accumulated. Interestingly, these apoptotic 4T1 tumor cells directly induced neutrophil extracellular traps (NETs) in a pannexin 1 (Panx1) channel-dependent manner, and knockdown of Panx1 in 4T1 cells led to a reduction in tumor size. Spermidine released through Panx1 from apoptotic 4T1 cells induced NETs in bone marrow-derived neutrophils in vitro. In addition, inhibition of spermidine synthesis suppressed tumor growth in the mouse transplant model. Collectively, our data suggested a new immune-escape mechanism for tumors by Panx1-mediated secretome from intrinsic apoptotic cells, which may provide a new therapeutic target for cancer.
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Trifosfato de Adenosina , Conexinas , Trifosfato de Adenosina/metabolismo , Conexinas/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neutrófilos/metabolismo , Secretoma , Espermidina/metabolismo , Microambiente TumoralRESUMO
Gut-associated lymphoid tissue (GALT), such as Peyer's patches (PPs), are key inductive sites that generate IgA+ B cells, mainly through germinal center (GC) responses. The generation of IgA+ B cells is promoted by the presence of gut microbiota and dietary antigens. However, the function of GALT in the large intestine, such as cecal patches (CePs) and colonic patches (CoPs), and their regulatory mechanisms remain largely unknown. In this study, we demonstrate that the CePs possess more IgG2b+ B cells and have fewer IgA+ B cells than those in PPs from BALB/c mice with normal gut microbiota. Gene expression analysis of postswitched transcripts supported the differential expression of dominant antibody isotypes in B cells in GALT. Germ-free (GF) mice showed diminished GC B cells and had few IgA+ or IgG2b+ switched B cells in both the small and large intestinal GALT. In contrast, myeloid differentiation factor 88- (MyD88-) deficient mice exhibited decreased GC B cells and presented with reduced numbers of IgG2b+ B cells in CePs but not in PPs. Using ex vivo cell culture, we showed that CePs have a greater capacity to produce total and microbiota-reactive IgG2b, in addition to microbiota-reactive IgA, than the PPs. In line with the frequency of GC B cells and IgG2b+ B cells in CePs, there was a decrease in the levels of microbiota-reactive IgG2b and IgA in the serum of GF and MyD88-deficient mice. These data suggest that CePs have a different antibody production profile compared to PPs. Furthermore, the innate immune signals derived from gut microbiota are crucial for generating the IgG2b antibodies in CePs.
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Microbioma Gastrointestinal , Nódulos Linfáticos Agregados , Animais , Imunoglobulina A/metabolismo , Imunoglobulina G/metabolismo , Camundongos , Fator 88 de Diferenciação Mieloide/metabolismo , Nódulos Linfáticos Agregados/metabolismoRESUMO
To evaluate the effect and outcome by Shokuiku and nutrition education, it is need to develop the reliability and validity questionnaire for behaviors and interests in healthy eating habits for Japanese adolescents. Our aim was to develop the reliability and validity questionnaire about them for Japanese adolescents. Interests in healthy eating habits for Japanese adolescents were modified Japanese questionnaire of consciousness in dietary life (JQCDL) for university students developed by Hamaguchi et al. The surveys were carried out at two public junior high schools and 381 students in second year participated. Reliability of JQCDL-adolescent form (JQCDL-AF) was examined by factor analysis and calculation of Cronbach's α. Validity of JQCDL-AF was examined by divergent of gender and by experimental intervention which investigated the changed scores from lunchbox to school lunch. High score of JQCDL-AF showed more interests in healthy eating habits. From histogram and factor analysis, four questions were excluded from JQCDL. We chose two subscale factors to form the domains: reduction unhealthy foods when eating out or snacking (4 items), and meal manners and meal preparation (7 items). Cronbach's α of two subscales and all items (11 questions) were 0.845, 0.826, and 0.860, respectively. The total JQCDL-AF scores in girls were significantly higher than those of boys. Moreover, the total JQCDL-AF scores 1-mo after introducing school lunches increased significantly from the lunchbox. Therefore, the JQCDL-AF could evaluate interests in healthy eating habits in Japanese adolescents.
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Dieta Saudável , Hábitos , Adolescente , Feminino , Humanos , Japão , Masculino , Reprodutibilidade dos Testes , Inquéritos e QuestionáriosRESUMO
Sialorrhea is a major cause of recurrent aspiration pneumonia in severe chronic brain injury. Previous reports have shown that transdermal scopolamine can decrease saliva production. We present four patients with severe chronic brain injury who experienced repeat aspiration pneumonia with sialorrhea. Longitudinal computed tomography examinations to assess the therapeutic effect were performed in all four cases before and after transdermal scopolamine. Transdermal scopolamine was applied as a patch (0.1 g/2.5 cm2) behind the earlobe every 24 h after confirming the absence of glaucoma. Patches were formulated as an in-hospital preparation (scopolamine butylbromide 0.25 g and hydrophilic cream 4.75 g) under the approval of our institutional review board. Longitudinal computed tomography after transdermal scopolamine use showed a decrease in pleural effusions associated with continuous aspiration pneumonia in all four cases. The data from repeat computed tomography suggest that long-term transdermal scopolamine for reducing saliva production may be a reasonable option for appropriate palliative care in severe chronic brain injury patients.
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BACKGROUND: Vitamin D deficiency (VDD) is associated with an increased risk for lifestyle-related diseases. In Japan, VDD is quite prevalent in all age groups, with its high risk in young women. Furthermore, its association during pregnancy with gestational hypertension and low birth weight has also been reported. VDD can be diagnosed by serum 25-hydroxyvitamin D [25(OH)D] levels, which, however, is not suited for screening. Therefore, we will create a predictive model for serum 25(OH)D concentration and prevalence of VDD based on such data as region, sun exposure habit, and vitamin D intake in young women. METHODS: From 2020 to 2022, we conduct a cross-sectional study of 600 young women in four regions of Japan, identify the indices associated with serum 25(OH)D concentrations such as sun exposure habits, habitual vitamin D intake, ultraviolet-B irradiation, seasons (summer and winter) and latitude, and construct prediction models for serum 25(OH)D concentrations and VDD risk. This study has been registered with UMIN-CTR (ID: UMIN000041527). RESULTS: One hundred and fifteen subjects have been collected from 6 institutions in winter as of May 2021. When data from more than 200 subjects have become available, we will conduct the interim analysis, summarize the data by region and facility, review the inclusion criteria for analysis, and check for missing values and outliers. Prediction models for serum 25(OH)D concentration and VDD will be determined in the final analysis when all cases have been collected. CONCLUSIONS: A screening tool for VDD risk to be developed in our study based on the predictive model would help the public and medical professionals prevent lifestyle-related diseases through improving VDD. Additionally, the results may serve as the scientific basis for determining the appropriate vitamin D intake and sun exposure standards.
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Deficiência de Vitamina D , Estudos Transversais , Feminino , Humanos , Japão/epidemiologia , Gravidez , Vitamina D , VitaminasRESUMO
Soybean flour is often used as a gluten-free ingredient. We aimed to compare the nutrients and the difference in satiety of soybean and wheat after ingestion. We measured the amounts of polyphenol and oxygen radical absorbance capacity (ORAC) and examined the acute appetite sensation after the ingestion of soybean powder and bread powder. Japanese women were enrolled in the meal tests. Participants were provided with 18 g of bread or soybean powder, 180 g of yogurt, and 285 mL of bottled water. Subjective satiety (hunger, appetite, satiety, and stomach fullness) was measured using a visual analog scale 120 min after sample ingestion. The polyphenol content and ORAC were 2- and 12-folds higher, respectively, in soybean powder than in bread flour. In the meal tests, the area under the curve (AUC) of satiety 60-120 min after ingestion (n = 44) was significantly higher for soybean powder than bread powder. The AUCs of hunger and appetite 60-120 min after ingestion were significantly lower for soybean powder than bread powder. The effect sizes of hunger and appetite by soybean powder were 0.341 and 0.424, respectively. Thus, these results suggest that soybean is a healthy food and soybeans maintain satiety and suppress hunger more than bread flour.
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Tofacitinib (TFT), a JAK inhibitor used for the treatment of rheumatoid arthritis and other diseases, is associated with severe liver injury that is believed to be caused by its reactive aldehyde or epoxide metabolites. In this study, we synthesized six tofacitinib analogs designed to avoid the formation of reactive metabolites and evaluated their JAK3 inhibitory activity, metabolic stability, CYP3A time-dependent inhibition, and cytotoxicity. Our data indicated that purine analog 3, which showed little inhibition of CYP3A and cytotoxicity and inhibited JAK3 in the nanomolar range, could be a safer drug candidate than TFT. In addition, the results of the bioactivation study using TFT and its analogs suggest that the epoxide metabolite might contribute to TFT-induced CYP3A4 mechanism-based inhibition and hepatic toxicity.
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Piperidinas , Pirimidinas , Ativação Metabólica , Citocromo P-450 CYP3A/metabolismo , Microssomos Hepáticos/metabolismo , Piperidinas/metabolismo , Piperidinas/farmacologia , Pirimidinas/metabolismo , Pirimidinas/farmacologiaRESUMO
In the treatment of breakpoint cluster region-Abelson (BCR-ABL)-positive chronic myeloid leukemia (CML) using BCR-ABL inhibitors, the appearance of a gatekeeper mutation (T315I) in BCR-ABL is a serious issue. Therefore, the development of novel drugs that overcome acquired resistance to BCR-ABL inhibitors by CML cells is required. We previously demonstrated that a bis-pyridinium fullerene derivative (BPF) induced apoptosis in human chronic myeloid leukemia (CML)-derived K562 cells partially through the generation of reactive oxygen species (ROS). We herein show that BPF enhanced the activation of the mitogen-activated protein kinase/extracellular signal-regulated kinase kinase-extracellular signal-regulated kinase (MEK-ERK) pathway in a ROS-independent manner. BPF-induced apoptosis was attenuated by trametinib, suggesting the functional involvement of the MEK-ERK pathway in apoptosis in K562 cells. In addition, the constitutive activation of the MEK-ERK pathway by the enforced expression of the BRAFV600E mutant significantly increased the sensitivity of K562 cells to BPF. These results confirmed for the first time that BPF induces apoptosis in K562 cells through dual pathways-ROS production and the activation of the MEK-ERK pathway. Furthermore, BPF induced cell death in transformed Ba/F3 cells expressing not only BCR-ABL but also T315I mutant through the activation of the MEK-ERK pathway. These results indicate that BPF is as an effective CML drug that overcomes resistance to BCR-ABL inhibitors.
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Apoptose/efeitos dos fármacos , Fulerenos/farmacologia , Proteínas de Fusão bcr-abl/genética , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Animais , Fulerenos/química , Genes Essenciais , Humanos , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Camundongos , Modelos Biológicos , Mutação , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismoRESUMO
A fusion protein, Breakpoint cluster region-Abelson (BCR-ABL) is responsible for the development of chronic myeloid leukemia (CML) and acute lymphocytic leukemia (ALL). Inhibitors against BCR-ABL are effective for the treatment of leukemia; however, a gatekeeper mutation (T315I) in BCR-ABL results in resistance to these inhibitors, which markedly impedes their efficacy. We herein demonstrated that a bis-pyridinium fullerene derivative (BPF) significantly induced apoptosis in human CML-derived K562 cells and ALL-derived SUP-B15 cells via the generation of reactive oxygen species (ROS). BPF reduced the expression of Bcr-Abl mRNA by inhibiting expression of c-Myc through ROS production. BPF also accelerated protein degradation of BCR-ABL through ROS production. Furthermore, BPF down-regulated the expression of not only BCR-ABL but also T315I-mutated BCR-ABL in ROS-dependent manner. As a result, BPF effectively induced apoptosis in transformed Ba/F3 cells expressing both BCR-ABL and T315I-mutated BCR-ABL. Collectively, these results indicate the potential of BPF as an effective leukemia drug that overcomes resistance to BCR-ABL inhibitors.
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Antineoplásicos , Fulerenos , Leucemia Mielogênica Crônica BCR-ABL Positiva , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose , Resistencia a Medicamentos Antineoplásicos , Fulerenos/química , Proteínas de Fusão bcr-abl/metabolismo , Humanos , Mesilato de Imatinib/farmacologia , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Espécies Reativas de Oxigênio/metabolismoRESUMO
BACKGROUND: Commercial spray-dried egg white (S-EW) is often used for oral immunotherapy (OIT). Peptifine® (PF), a commercial preparation of enzymatically-hydrolyzed egg white (EW) peptides, is considered safe OIT food. OBJECTIVE: Here, we examined the therapeutic effect of PF or S-EW in a mouse model of EW allergy. METHODS: Sensitized female BALB/c mice underwent 4-week OIT by supplementation of 19% casein diet with 1% PF (PF group) or S-EW (S-EW group), and non-supplementation of 20% casein diet (non-OIT group). Non-sensitized mice acted as the non-allergy group. Oral and intraperitoneal EW challenges were performed and allergic biomarkers were determined. RESULTS: Changes in rectal temperature after oral challenge were comparable in the allergy groups. However, after intraperitoneal challenge, rectal temperature decrease in the PF and S-EW groups was lower than in the non-OIT group. After 4 weeks, plasma levels of ovalbumin- and ovomucoid-specific antibodies were assessed; IgE levels in the PF and S-EW groups were lower than those in the non-OIT group. Interleukin-4 secretion after EW challenge was significantly lower in splenocyte cultures derived from PF and S-EW groups than in the non-OIT group. Furthermore, the percentage of CD4+ Foxp3+ splenocytes in the PF group was significantly higher than that in the non-OIT and S-EW groups. Oral gavage of 40 mg PF did not induce an allergic response in sensitized mice with EW. CONCLUSIONS: Diet supplementation with 1% PF mildly ameliorated the severity of allergy in mouse with EW allergy, indicating that PF is a safe OIT food.