The Experts below are selected from a list of 234 Experts worldwide ranked by ideXlab platform
Shunji Sugawara - One of the best experts on this subject based on the ideXlab platform.
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Biotin deficiency up regulates tnf α production in murine macrophages
Journal of Leukocyte Biology, 2008Co-Authors: Toshinobu Kuroishi, Yasuo Endo, Koji Muramoto, Shunji SugawaraAbstract:Biotin, a water-soluble vitamin of the B complex, functions as a cofactor of carboxylases that catalyze an indispensable cellular metabolism. Although significant decreases in serum Biotin lev- els have been reported in patients with chronic inflammatory diseases, the biological roles of Biotin in inflammatory responses are unclear. In this study, we investigated the effects of Biotin defi- ciency on TNF- production. Mice were fed a basal diet or a Biotin-deficient diet for 8 weeks. Serum Biotin levels were significantly lower in Biotin-defi- cient mice than Biotin-sufficient mice. After i.v. administration of LPS, serum TNF- levels were significantly higher in Biotin-deficient mice than Biotin-sufficient mice. A murine macrophage-like cell line, J774.1, was cultured in a Biotin-sufficient or -deficient medium for 4 weeks. Cell prolifera- tion and Biotinylation of intracellular proteins were decreased significantly in Biotin-deficient cells compared with Biotin-sufficient cells. Significantly higher production and mRNA expression of TNF- were detected in Biotin-deficient J774.1 cells than Biotin-sufficient cells in response to LPS and even without LPS stimulation. Intracellular TNF- ex- pression was inhibited by actinomycin D, indicating that Biotin deficiency up-regulates TNF- produc- tion at the transcriptional level. However, the ex- pression levels of TNF receptors, CD14, and TLR4/myeloid differentiation protein 2 complex were similar between Biotin-sufficient and -defi- cient cells. No differences were detected in the activities of the NF-B family or AP-1. The TNF- induction by Biotin deficiency was down-regulated by Biotin supplementation in vitro and in vivo. These results indicate that Biotin deficiency may up-regulate TNF- production or that Biotin ex- cess down-regulates TNF- production, suggesting that Biotin status may influence inflammatory diseases. J. Leukoc. Biol. 83: 000-000; 2008.
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Biotin deficiency up regulates tnf a production in vivo and in vitro
2007Co-Authors: Toshinobu Kuroishi, Yasuo Endo, Shunji SugawaraAbstract:Biotin, a water-soluble vitamin of the B complex, functions as a cofactor of carboxylases that catalyze indispensable cellular metabolism. It was reported that the concentrations of Biotin were significantly lower in sera of patients with chronic inflammatory diseases. However, the biological roles of Biotin in inflammatory responses are unclear. In this study, we investigated the effects of Biotin-deficiency on tumor necrosis factor (TNF)-α production in vivo and in vitro. Mice were fed a basal diet or a Biotin-deficient diet for 8 weeks. After intravenous administration of lipopolysaccharide (LPS), serum TNF-α levels in Biotin-deficient mice were significantly higher than those in Biotin-sufficient mice. A murine macrophage-like cell line, J774.1, was cultured in Biotin-sufficient or Biotin-deficient medium. Biotindefi cient J774.1 cells produced TNF-α significantly higher than Biotin-sufficient J774.1 cells in response to LPS and even without LPS stimulation. Moreover, Biotin-supplementation inhibited TNF-α production of Biotin-deficient cells. Addition of cyclic guanosine 5′-monophosphate (cGMP) significantly decreased TNF-α production of the Biotin-deficient cells, indicating that up-regulation of TNF-α production was regulated by cGMP-dependent signaling pathways. In conclusion, these results suggest that Biotin is critically involved in inflammatory diseases via the regulation of TNF-α production in vivo and in vitro.
Donald M Mock - One of the best experts on this subject based on the ideXlab platform.
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Biotin accounts for less than half of all Biotin and Biotin metabolites in the cerebrospinal fluid of children.
The American journal of clinical nutrition, 2008Co-Authors: Anna Bogusiewicz, Shawna L Stratton, Dale A. Ellison, Donald M MockAbstract:Background Biotin is likely transported into cerebral spinal fluid (CSF) via one or more specific transporters. Concentrations of Biotin in CSF measured by using modern analytic techniques that are specific for Biotin and Biotin metabolites have not previously been reported. Objectives We aimed to accurately measure the concentration of Biotin and major Biotin metabolites, Biotin sulfoxide (BSO) and bisnorBiotin (BNB), in the CSF of children. Design Concentrations of Biotin were determined initially as total avidin-binding substances (TABS) in CSF obtained by lumbar puncture from 55 children. Biotin, BSO, and BNB were quantitated by HPLC and an avidin-binding assay in CSF samples from a subset of 11 children. Results Concentrations of TABS in CSF averaged 1.6 nmol/L with substantial variability (SD = 1.3 nmol/L). CSF concentrations of Biotin and Biotin analogs varied widely, but substantial amounts of BSO were detected in every sample. Biotin accounted for 42 +/- 16%, BSO for 41 +/- 12%, and BNB for 8 +/- 14% of the total. It was surprising that the molar sum of Biotin, BSO, and BNB on average was >200-fold the TABS concentrations from the same CSF sample. Using several analytic approaches, we found no masking of detection, nor did we find degradation of Biotin or BSO. Gel electrophoresis and streptavidin Western blot detected several Biotinylated proteins in CSF. Conclusions Biotin appears to be bound to protein covalently, reversibly, or both, and this binding likely accounts for the increase in detectable Biotin after HPLC. Protein-bound Biotin may play an important role in Biotin nutriture of the brain.
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Biotin deficiency reduces expression of slc19a3 a potential Biotin transporter in leukocytes from human blood
Journal of Nutrition, 2005Co-Authors: Tatyana I Vlasova, Nell I Mock, Shawna L Stratton, Amanda M Wells, Donald M MockAbstract:Biotin deficiency is teratogenic in mice (1,2) and may be teratogenic in humans (3). Valid indicators of marginal and moderate Biotin deficiency would be useful in investigating the role of Biotin deficiency in birth defects and in other illnesses hypothesized to be Biotin related (4 –7). Emerging evidence indicates that Biotin plays a role in gene expression (8 –12). In addition to acting as a cofactor for Biotin-dependent carboxylases, Biotin stimulates expression of hepatic glucokinase (8) and represses expression of hepatic phosphoenolpyruvate carboxylase (9) in vivo, and expression of the Biotin-related enzymes propionyl-CoA carboxylase chain A (PCCA),4 acetyl-CoA carboxylase isoform A (ACCA), and holocarboxylase synthetase (HCS) in cultured human hepatoblastoma cells and normal fibroblasts (10). However, no such studies have been performed in humans in vivo. In this study, we examined the expression of specific Biotin-related genes as indicators of marginal, asymptomatic Biotin deficiency and assessed gene response to marginal Biotin deficiency. In mammals, Biotin is a coenzyme for 5 Biotin-dependent carboxylases: methylcrotonyl-CoA carboxylase (MCC), propionyl-CoA carboxylase (PCC), pyruvate carboxylase (PC), and the 2 isoforms of ACC (ACCA and ACCB). The active forms of the enzymes (holocarboxylases) contain Biotin covalently bound to lysine residues; the attachment of Biotin to the corresponding apocarboxylase is catalyzed by HCS. Biotin is transported into eukaryotic cells by Biotin transporters located in cell membranes. Three Biotin transporters have been proposed in human cells: 1) the sodium-dependent multivitamin transporter (SMVT) (13,14); 2) the solute carrier family 19 member 3 (SLC19A3) (15,16); and 3) the monocarboxylate transporter R1 (17). This third transporter was proposed after this study was initiated and was not examined here. Biotinidase catalyzes the release of covalently bound Biotin from Biotinyl-peptides generated by the turnover of intracellular proteins and releases Biotin from dietary proteins during digestion (18). Biotinidase is also likely important in catalyzing the covalent binding of Biotin to histones (19). In this study, we evaluated expression of Biotin-related genes as potential indicators of marginal, asymptomatic Biotin deficiency. Gene expression was quantitated in leukocytes of 7 healthy humans after 28 d of progressive Biotin deficiency.
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marginal Biotin deficiency is teratogenic in icr mice
Journal of Nutrition, 2003Co-Authors: Donald M Mock, Nell I Mock, Christopher W Stewart, James B Laborde, Deborah K HansenAbstract:: The incidence of marginal Biotin deficiency in normal human gestation is approximately one in three. In ICR mice, maternal Biotin deficiency results in cleft palate, micrognathia, microglossia and limb hypoplasia. However, the relationships among the severity of maternal Biotin deficiency, fetal Biotin status and malformations have not been reported. This study utilized validated indices of Biotin status to investigate the relationships among maternal Biotin status, fetal Biotin status and the rate of fetal malformations in ICR mice. Biotin status was controlled by feeding diets with varying egg white concentration. In dams and fetuses, Biotin status was assessed by hepatic Biotin content and hepatic activity of the Biotin-dependent enzyme propionyl-CoA carboxylase; in dams, status was also assessed by urinary excretion of Biotin and 3-hydroxyisovaleric acid. Malformations were assessed morphologically. Biotin was measured by HPLC/avidin-binding assay. Propionyl-CoA carboxylase (PCC) activity was determined by H(14)CO(3) incorporation. 3-Hydroxyisovaleric acid concentration was determined by GC/MS. Although no overt signs of deficiency appeared, metabolic disturbances caused by Biotin deficiency were detectable in dams and fetuses. These disturbances increased with increasing egg white. Fetal Biotin status correlated significantly with maternal Biotin status (fetal vs. dam hepatic Biotin, r = 0.671; fetal vs. dam PCC activity, r = 0.70). The incidences of malformations were strikingly dependent on egg white concentration. We conclude that in ICR mice, marginal maternal Biotin deficiency causes fetal Biotin deficiency. We speculate that the fetal malformations are primarily the consequence of fetal Biotin deficiency. Because murine malformations appeared at degrees of Biotin deficiency that are similar to those in human gestation, we speculate that some human fetal malformations may be caused by Biotin deficiency.
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lymphocyte propionyl coa carboxylase is an early and sensitive indicator of Biotin deficiency in rats but urinary excretion of 3 hydroxypropionic acid is not
Journal of Nutrition, 2002Co-Authors: Donald M Mock, Nell I MockAbstract:Recent clinical studies indicate that marginal, asymptomatic Biotin deficiency may be a common occurrence in normal human gestation (1–3) and in individuals treated for extended periods with certain anticonvulsants (4 –9). In rats (10) and humans (11), reduced urinary excretion of Biotin and increased urinary excretion of 3-hydroxyisovaleric acid (3HIA),3 are early and sensitive indicators of impaired Biotin deficiency. Both of these validated indicators depend on renal function. Increased 3HIA excretion reflects decreased activity of the Biotin-dependent enzyme methylcrotonyl-CoA carboxylase. Development of a valid indicator of Biotin status that does not depend on renal function would likely be useful. Unfortunately, the plasma concentration of Biotin is not particularly useful in detecting marginal Biotin deficiency (11). The concentration of Biotin in erythrocytes is similar to the plasma concentration in the same blood sample (unpublished data); thus is not likely to be useful for detecting marginal Biotin deficiency. Propionyl-CoA carboxylase (PCC) is a Biotin-dependent enzyme found in a variety of tissues including liver and lymphocytes. Studies of Biotin-deficient patients receiving parenteral nutrition (12) or suffering from protein-energy malnutrition (13) suggest that lymphocyte PCC activity reflects Biotin status in moderate-to-severe Biotin deficiency. Using egg-white–fed rats, a well-established model of Biotin deficiency, we sought to determine whether the activity of the PCC in lymphocytes is useful in detecting marginal Biotin deficiency. We also evaluated whether urinary excretion of 3-hydroxypropionic acid (3HPA), an organic acid that reflects decreased activity of PCC, is useful in detecting marginal Biotin deficiency in this rat model.
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Biotin dependency due to a defect in Biotin transport
The Journal of clinical investigation, 2002Co-Authors: Rebecca Mardach, Barry Wolf, Janos Zempleni, Martin J. Cannon, Michael L. Jennings, Sally Cress, Jane Boylan, Susan Roth, Stephen D. Cederbaum, Donald M MockAbstract:We describe a 3-year-old boy with Biotin dependency not caused by Biotinidase, holocarboxylase synthetase, or nutritional Biotin deficiency. We sought to define the mechanism of his Biotin dependency. The child became acutely encephalopathic at age 18 months. Urinary organic acids indicated deficiency of several Biotin-dependent carboxylases. Symptoms improved rapidly following Biotin supplementation. Serum Biotinidase activity and Biotinidase gene sequence were normal. Activities of Biotin-dependent carboxylases in PBMCs and cultured skin fibroblasts were normal, excluding Biotin holocarboxylase synthetase deficiency. Despite extracellular Biotin sufficiency, Biotin withdrawal caused recurrent abnormal organic aciduria, indicating intracellular Biotin deficiency. Biotin uptake rates into fresh PBMCs from the child and into his PBMCs transformed with Epstein Barr virus were about 10% of normal fresh and transformed control cells, respectively. For fresh and transformed PBMCs from his parents, Biotin uptake rates were consistent with heterozygosity for an autosomal recessive genetic defect. Increased Biotin breakdown was ruled out, as were artifacts of Biotin supplementation and generalized defects in membrane permeability for Biotin. These results provide evidence for a novel genetic defect in Biotin transport. This child is the first known with this defect, which should now be included in the identified causes of Biotin dependency.
Toshinobu Kuroishi - One of the best experts on this subject based on the ideXlab platform.
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Biotin deficiency up regulates tnf α production in murine macrophages
Journal of Leukocyte Biology, 2008Co-Authors: Toshinobu Kuroishi, Yasuo Endo, Koji Muramoto, Shunji SugawaraAbstract:Biotin, a water-soluble vitamin of the B complex, functions as a cofactor of carboxylases that catalyze an indispensable cellular metabolism. Although significant decreases in serum Biotin lev- els have been reported in patients with chronic inflammatory diseases, the biological roles of Biotin in inflammatory responses are unclear. In this study, we investigated the effects of Biotin defi- ciency on TNF- production. Mice were fed a basal diet or a Biotin-deficient diet for 8 weeks. Serum Biotin levels were significantly lower in Biotin-defi- cient mice than Biotin-sufficient mice. After i.v. administration of LPS, serum TNF- levels were significantly higher in Biotin-deficient mice than Biotin-sufficient mice. A murine macrophage-like cell line, J774.1, was cultured in a Biotin-sufficient or -deficient medium for 4 weeks. Cell prolifera- tion and Biotinylation of intracellular proteins were decreased significantly in Biotin-deficient cells compared with Biotin-sufficient cells. Significantly higher production and mRNA expression of TNF- were detected in Biotin-deficient J774.1 cells than Biotin-sufficient cells in response to LPS and even without LPS stimulation. Intracellular TNF- ex- pression was inhibited by actinomycin D, indicating that Biotin deficiency up-regulates TNF- produc- tion at the transcriptional level. However, the ex- pression levels of TNF receptors, CD14, and TLR4/myeloid differentiation protein 2 complex were similar between Biotin-sufficient and -defi- cient cells. No differences were detected in the activities of the NF-B family or AP-1. The TNF- induction by Biotin deficiency was down-regulated by Biotin supplementation in vitro and in vivo. These results indicate that Biotin deficiency may up-regulate TNF- production or that Biotin ex- cess down-regulates TNF- production, suggesting that Biotin status may influence inflammatory diseases. J. Leukoc. Biol. 83: 000-000; 2008.
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Biotin deficiency up regulates tnf a production in vivo and in vitro
2007Co-Authors: Toshinobu Kuroishi, Yasuo Endo, Shunji SugawaraAbstract:Biotin, a water-soluble vitamin of the B complex, functions as a cofactor of carboxylases that catalyze indispensable cellular metabolism. It was reported that the concentrations of Biotin were significantly lower in sera of patients with chronic inflammatory diseases. However, the biological roles of Biotin in inflammatory responses are unclear. In this study, we investigated the effects of Biotin-deficiency on tumor necrosis factor (TNF)-α production in vivo and in vitro. Mice were fed a basal diet or a Biotin-deficient diet for 8 weeks. After intravenous administration of lipopolysaccharide (LPS), serum TNF-α levels in Biotin-deficient mice were significantly higher than those in Biotin-sufficient mice. A murine macrophage-like cell line, J774.1, was cultured in Biotin-sufficient or Biotin-deficient medium. Biotindefi cient J774.1 cells produced TNF-α significantly higher than Biotin-sufficient J774.1 cells in response to LPS and even without LPS stimulation. Moreover, Biotin-supplementation inhibited TNF-α production of Biotin-deficient cells. Addition of cyclic guanosine 5′-monophosphate (cGMP) significantly decreased TNF-α production of the Biotin-deficient cells, indicating that up-regulation of TNF-α production was regulated by cGMP-dependent signaling pathways. In conclusion, these results suggest that Biotin is critically involved in inflammatory diseases via the regulation of TNF-α production in vivo and in vitro.
Yasuo Endo - One of the best experts on this subject based on the ideXlab platform.
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Biotin deficiency up regulates tnf α production in murine macrophages
Journal of Leukocyte Biology, 2008Co-Authors: Toshinobu Kuroishi, Yasuo Endo, Koji Muramoto, Shunji SugawaraAbstract:Biotin, a water-soluble vitamin of the B complex, functions as a cofactor of carboxylases that catalyze an indispensable cellular metabolism. Although significant decreases in serum Biotin lev- els have been reported in patients with chronic inflammatory diseases, the biological roles of Biotin in inflammatory responses are unclear. In this study, we investigated the effects of Biotin defi- ciency on TNF- production. Mice were fed a basal diet or a Biotin-deficient diet for 8 weeks. Serum Biotin levels were significantly lower in Biotin-defi- cient mice than Biotin-sufficient mice. After i.v. administration of LPS, serum TNF- levels were significantly higher in Biotin-deficient mice than Biotin-sufficient mice. A murine macrophage-like cell line, J774.1, was cultured in a Biotin-sufficient or -deficient medium for 4 weeks. Cell prolifera- tion and Biotinylation of intracellular proteins were decreased significantly in Biotin-deficient cells compared with Biotin-sufficient cells. Significantly higher production and mRNA expression of TNF- were detected in Biotin-deficient J774.1 cells than Biotin-sufficient cells in response to LPS and even without LPS stimulation. Intracellular TNF- ex- pression was inhibited by actinomycin D, indicating that Biotin deficiency up-regulates TNF- produc- tion at the transcriptional level. However, the ex- pression levels of TNF receptors, CD14, and TLR4/myeloid differentiation protein 2 complex were similar between Biotin-sufficient and -defi- cient cells. No differences were detected in the activities of the NF-B family or AP-1. The TNF- induction by Biotin deficiency was down-regulated by Biotin supplementation in vitro and in vivo. These results indicate that Biotin deficiency may up-regulate TNF- production or that Biotin ex- cess down-regulates TNF- production, suggesting that Biotin status may influence inflammatory diseases. J. Leukoc. Biol. 83: 000-000; 2008.
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Biotin deficiency up regulates tnf a production in vivo and in vitro
2007Co-Authors: Toshinobu Kuroishi, Yasuo Endo, Shunji SugawaraAbstract:Biotin, a water-soluble vitamin of the B complex, functions as a cofactor of carboxylases that catalyze indispensable cellular metabolism. It was reported that the concentrations of Biotin were significantly lower in sera of patients with chronic inflammatory diseases. However, the biological roles of Biotin in inflammatory responses are unclear. In this study, we investigated the effects of Biotin-deficiency on tumor necrosis factor (TNF)-α production in vivo and in vitro. Mice were fed a basal diet or a Biotin-deficient diet for 8 weeks. After intravenous administration of lipopolysaccharide (LPS), serum TNF-α levels in Biotin-deficient mice were significantly higher than those in Biotin-sufficient mice. A murine macrophage-like cell line, J774.1, was cultured in Biotin-sufficient or Biotin-deficient medium. Biotindefi cient J774.1 cells produced TNF-α significantly higher than Biotin-sufficient J774.1 cells in response to LPS and even without LPS stimulation. Moreover, Biotin-supplementation inhibited TNF-α production of Biotin-deficient cells. Addition of cyclic guanosine 5′-monophosphate (cGMP) significantly decreased TNF-α production of the Biotin-deficient cells, indicating that up-regulation of TNF-α production was regulated by cGMP-dependent signaling pathways. In conclusion, these results suggest that Biotin is critically involved in inflammatory diseases via the regulation of TNF-α production in vivo and in vitro.
George P. Anderson - One of the best experts on this subject based on the ideXlab platform.
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Conjugation of Biotin-coated luminescent quantum dots with single domain antibody-rhizavidin fusions.
Biotechnology Reports, 2016Co-Authors: Scott A. Walper, Kendrick B. Turner, Kimihiro Susumu, Dan Zabetakis, Eunkeu Oh, Ellen R. Goldman, Igor L. Medintz, George P. AndersonAbstract:Abstract Straightforward and effective methods are required for the bioconjugation of proteins to surfaces and particles. Previously we demonstrated that the fusion of a single domain antibody with the Biotin binding molecule rhizavidin provided a facile method to coat Biotin-modified surfaces with a highly active and oriented antibody. Here, we constructed similar single domain antibody—rhizavidin fusions as well as unfused rhizavidin with a His-tag. The unfused rhizavidin produced efficiently and its utility for assay development was demonstrated in surface plasmon resonance experiments. The single domain antibody-rhizavidin fusions were utilized to coat quantum dots that had been prepared with surface Biotins. Preparation of antibody coated quantum dots by this means was found to be both easy and effective. The prepared single domain antibody-quantum dot reagent was characterized by surface plasmon resonance and applied to toxin detection in a fluoroimmunoassay sensing format.