53 research outputs found

    Effects of cellooligosaccharide or a combination of cellooligosaccharide and live Clostridium butyricum culture on performance and intestinal ecology in Holstein calves fed milk or milk replacer

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    The effects of oral administration of a prebiotic (cellooligosaccharide [CE]) and a combination of a probiotic (a commercial Clostridium butyricum strain) and prebiotics (referred to as symbiotics [SB]) on performance and intestinal ecology in Holstein calves fed milk replacer (MR) or whole milk were evaluated. Forty female calves (experiment 1) and 14 male and female calves (experiment 2) were used in this study. Calves were fed MR (experiment 1) or whole milk (experiment 2) necessary for daily weight gain of 0.3 kg based on birth weight in two daily feedings and weaned at 46 days. Calves were divided into a CE feeding group, SB feeding group (only in experiment 1), and control group. The CE and SB groups were fed CE at 5 g/day before weaning and 10 g/day postweaning. Only the SB group received 108 colony-forming units (CFU) of C butyricum culture per day. Commercial calf starter was offered for ad libitum intake. Health and feed intake of the animals were monitored daily, and body weight was measured weekly. Fecal samples were analyzed for determination of bacterial community composition by an RNA-based method (sequence-specific SSU rRNA cleavage method) and for organic acid profiling. In 49-day experiments, feed intake, daily gain, and occurrence of diarrhea of the calves were unaffected by either CE supplementation or SB supplementation, and all calves were healthy during each experiment. The fecal bacterial community compositions and the organic acid profiles were not different among groups in experiment 1. In experiment 2, the level of the Clostridium coccoides-Eubacterium rectale group was higher in the feces of CE group than controls at 4 weeks of age and fecal butyric acid concentration was higher (8.0 vs. 12.2 [mmol/kg feces], P <0.05) at that time. There were no differences in prebiotic bacteria (the genera Lactobacillus and Bifidobacterium) between groups at this time point. These results suggested that CE and C. butyricum supplementation have less effect on the performance of healthy calves fed MR. However, prebiotic supplementation seems effective for modulation of the intestinal bacterial community of calves when administered with whole milk.ArticleLIVESTOCK SCIENCE. 153(1-3):88-93 (2013)journal articl

    Palmitate induces reactive oxygen species production and β-cell dysfunction by activating nicotinamide adenine dinucleotide phosphate oxidase through Src signaling.

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    [Aims/Introduction]Chronic hyperlipidemia impairs pancreatic β-cell function, referred to as lipotoxicity. We have reported an important role of endogenous reactive oxygen species (ROS) overproduction by activation of Src, a non-receptor tyrosine kinase, in impaired glucose-induced insulin secretion (GIIS) from diabetic rat islets. In the present study, we investigated the role of ROS production by Src signaling in palmitate-induced dysfunction of β-cells. [Materials and Methods]After rat insulinoma INS-1D cells were exposed to 0.6 mmol/L palmitate for 24 h (palmitate exposure); GIIS, ROS production and nicotinamide adenine dinucleotide phosphate oxidase (NOX) activity were examined with or without exposure to10 μmol/L 4-amino-5-(4-chlorophenyl)-7-(t-butyl)pyrazolo[3,4-d]pyrimidine (PP2), a Src inhibitior, for 30 or 60 min. [Results]Exposure to PP2 recovered impaired GIIS and decreased ROS overproduction as a result of palmitate exposure. Palmitate exposure increased activity of NOX and protein levels of NOX2, a pathological ROS source in β-cells. Palmitate exposure increased the protein level of p47phox, a regulatory protein of NOX2, in membrane fraction compared with control, which was reduced by PP2. Transfection of small interfering ribonucleic acid of p47phox suppressed the augmented p47phox protein level in membrane fraction, decreased augmented ROS production and increased impaired GΙIS by palmitate exposure. In addition, exposure to PP2 ameliorated impaired GIIS and decreased ROS production in isolated islets of KK-Ay mice, an obese diabetic model with hyperlipidemia. [Conclusions]Activation of NOX through Src signaling plays an important role in ROS overproduction and impaired GΙIS caused by chronic exposure to palmitate, suggesting a lipotoxic mechanism of β-cell dysfunction of obese mice

    Single-Cell Transcriptome Analysis Dissects the Replicating Process of Pancreatic Beta Cells in Partial Pancreatectomy Model

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    膵臓ベータ細胞の増殖プロセスを時系列解析 --糖尿病の新規治療開発に期待--. 京都大学プレスリリース. 2020-12-24.Heterogeneity of gene expression and rarity of replication hamper molecular analysis of β-cell mass restoration in adult pancreas. Here, we show transcriptional dynamics in β-cell replication process by single-cell RNA sequencing of murine pancreas with or without partial pancreatectomy. We observed heterogeneity of Ins1-expressing β-cells and identified the one cluster as replicating β-cells with high expression of cell proliferation markers Pcna and Mki67. We also recapitulated cell cycle transition accompanied with switching expression of cyclins and E2F transcription factors. Both transient activation of endoplasmic reticulum stress responders like Atf6 and Hspa5 and elevated expression of tumor suppressors like Trp53, Rb1, and Brca1 and DNA damage responders like Atm, Atr, Rad51, Chek1, and Chek2 during the transition to replication associated fine balance of cell cycle progression and protection from DNA damage. Taken together, these results provide a high-resolution map depicting a sophisticated genetic circuit for replication of the β-cells

    Endometrial receptivity and implantation require uterine BMP signaling through an ACVR2A-SMAD1/SMAD5 axis.

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    During early pregnancy in the mouse, nidatory estrogen (E2) stimulates endometrial receptivity by activating a network of signaling pathways that is not yet fully characterized. Here, we report that bone morphogenetic proteins (BMPs) control endometrial receptivity via a conserved activin receptor type 2 A (ACVR2A) and SMAD1/5 signaling pathway. Mice were generated to contain single or double conditional deletion of SMAD1/5 and ACVR2A/ACVR2B receptors using progesterone receptor (PR)-cre. Female mice with SMAD1/5 deletion display endometrial defects that result in the development of cystic endometrial glands, a hyperproliferative endometrial epithelium during the window of implantation, and impaired apicobasal transformation that prevents embryo implantation and leads to infertility. Analysis of Acvr2a-PRcre and Acvr2b-PRcre pregnant mice determined that BMP signaling occurs via ACVR2A and that ACVR2B is dispensable during embryo implantation. Therefore, BMPs signal through a conserved endometrial ACVR2A/SMAD1/5 pathway that promotes endometrial receptivity during embryo implantation

    Effects of cellooligosaccharide or a combination of cellooligosaccharide and live Clostridium butyricum culture on performance and intestinal ecology in Holstein calves fed milk or milk replacer

    Get PDF
    The effects of oral administration of a prebiotic (cellooligosaccharide [CE]) and a combination of a probiotic (a commercial Clostridium butyricum strain) and prebiotics (referred to as symbiotics [SB]) on performance and intestinal ecology in Holstein calves fed milk replacer (MR) or whole milk were evaluated. Forty female calves (experiment 1) and 14 male and female calves (experiment 2) were used in this study. Calves were fed MR (experiment 1) or whole milk (experiment 2) necessary for daily weight gain of 0.3 kg based on birth weight in two daily feedings and weaned at 46 days. Calves were divided into a CE feeding group, SB feeding group (only in experiment 1), and control group. The CE and SB groups were fed CE at 5 g/day before weaning and 10 g/day postweaning. Only the SB group received 108 colony-forming units (CFU) of C butyricum culture per day. Commercial calf starter was offered for ad libitum intake. Health and feed intake of the animals were monitored daily, and body weight was measured weekly. Fecal samples were analyzed for determination of bacterial community composition by an RNA-based method (sequence-specific SSU rRNA cleavage method) and for organic acid profiling. In 49-day experiments, feed intake, daily gain, and occurrence of diarrhea of the calves were unaffected by either CE supplementation or SB supplementation, and all calves were healthy during each experiment. The fecal bacterial community compositions and the organic acid profiles were not different among groups in experiment 1. In experiment 2, the level of the Clostridium coccoides-Eubacterium rectale group was higher in the feces of CE group than controls at 4 weeks of age and fecal butyric acid concentration was higher (8.0 vs. 12.2 [mmol/kg feces], P <0.05) at that time. There were no differences in prebiotic bacteria (the genera Lactobacillus and Bifidobacterium) between groups at this time point. These results suggested that CE and C. butyricum supplementation have less effect on the performance of healthy calves fed MR. However, prebiotic supplementation seems effective for modulation of the intestinal bacterial community of calves when administered with whole milk.ArticleLIVESTOCK SCIENCE. 153(1-3):88-93 (2013)journal articl

    Expression of O6-methylguanine DNA methyltransferase (MGMT) and immunohistochemical analysis of 12 pineal parenchymal tumors

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    Pineal parenchymal tumors (PPTs) are rare neoplasms which occupy less than 1% of primary central nervous system tumors. Because of their rare incidence, the previous reports on PPTs are limited in number and the useful molecular markers for deciding the histological grading and even selecting chemotherapy are undetermined. In this study, we conducted immunohistochemical analysis of 12 PPT specimens, especially for expression of O6-methylguanine DNA methyltransferase (MGMT) to assess whether temozolomide (TMZ) could serve as a possible alternative therapy for PPTs. We analyzed 12 PPTs consisting of 3 pineocytomas, 6 pineal parenchymal tumors of intermediate differentiation (PPTIDs), and 3 pineoblastomas. Immunohistochemical analysis was performed using antibody against MGMT, synaptophysin, neurofilament protein (NF), p53, and NeuN. Immunohistochemically, 11 out of 12 cases were positive for MGMT. The mean MIB-1 labeling index was less than 1% in pineocytoma, 3.5% in PPTID, and 10.5% in pineoblastoma. All 12 cases were positive for synaptophysin and 11 cases except 1 PPTID case showed positive for NF. Nuclear staining of NeuN was negative in all cases although cytoplasmic stain of NeuN was observed in 5 cases. No case was positive for p53. Eleven out of 12 cases of PPTs demonstrated MGMT expression, suggesting chemoresistancy to TMZ treatment. This is the first report showing MGMT expression in PPTs. In addition, MIB-1 labeling index correlated with WHO grade, although the immunoreactivity of synaptophysin, NF, NeuN, and p53 did not correlate with the histological grade

    Oral Administration of Apple Procyanidins Ameliorates Insulin Resistance via Suppression of Pro-inflammatory Cytokines Expression in Liver of Diabetic ob/ob Mice

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    Genetic factors are important determinants of the onset and progression of diabetes mellitus. Numerous susceptibility genes for type 2 diabetes, including potassium voltage-gated channel, KQT-like subfamily Q, member1 (KCNQ1), have been identified in humans by genome-wide analyses and other studies. Experiments with genetically modified mice have also implicated various genes in the pathogenesis of diabetes. However, the possible effects of the parent of origin for diabetes susceptibility alleles on disease onset have remained unclear. Here, we show that a mutation at the Kcnq1 locus reduces pancreatic β-cell mass in mice by epigenetic modulation only when it is inherited from the father. The noncoding RNA KCNQ1 overlapping transcript1 (Kcnq1ot1) is expressed from the Kcnq1 locus and regulates the expression of neighboring genes on the paternal allele. We found that disruption of Kcnq1 results in reduced Kcnq1ot1 expression as well as the increased expression of cyclin-dependent kinase inhibitor 1C (Cdkn1c), an imprinted gene that encodes a cell cycle inhibitor, only when the mutation is on the paternal allele. Furthermore, histone modification at the Cdkn1c promoter region in pancreatic islets was found to contribute to this phenomenon. Our observations suggest that the Kcnq1 genomic region directly regulates pancreatic β-cell mass and that genomic imprinting may be a determinant of the onset of diabetes mellitus
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