2021
FGF23 signalling and physiology.
Ho BB, Bergwitz C. FGF23 signalling and physiology. Journal Of Molecular Endocrinology 2021, 66: r23-r32. PMID: 33338030, PMCID: PMC8782161, DOI: 10.1530/jme-20-0178.Peer-Reviewed Reviews, Practice Guidelines, Standards, and Consensus StatementsConceptsO-glycosylation of FGF23FGF23 signalingSubtilisin-like proprotein convertase furinSuppressing phosphate reabsorptionProprotein convertase furinPost-translationallyO-glycosylationIntact FGF23C-terminusGenetic activityPrevent proteolysisParacrine FGFsHigh-affinity binding sitesFibroblast growth factor 23Fruit flyActive intact FGF23Convertase furinChronic kidney diseaseFGF23 fragmentsGrowth factor 23Physiological roleEndocrine FGFsDihydroxyvitamin D synthesisHyperphosphatemic disordersIntestinal phosphate absorption
2020
Different elemental infant formulas show equivalent phosphorus and calcium bioavailability in healthy volunteers
Bergwitz C, Eussen SRBM, Janssens PLHR, Visser M, Carpenter TO, van Helvoort A. Different elemental infant formulas show equivalent phosphorus and calcium bioavailability in healthy volunteers. Nutrition Research 2020, 85: 71-83. PMID: 33450668, DOI: 10.1016/j.nutres.2020.11.004.Peer-Reviewed Original ResearchConceptsGeometric mean ratiosAcid-suppressive medicationsArea under the curveHealthy volunteersSerum phosphateCalcium bioavailabilityGastric acid-suppressive medicationsRetrospective chart reviewSerum calcium concentrationBioavailability of phosphorusCross-over studyInfant formulaElemental formula useSingle oral doseCalcium excretionDouble-blindGram of phosphorusSingle-centerChart reviewOral doseOvernight fastingSerum phosphorusBioequivalence criteriaWashout periodMean ratiosImportance of Dietary Phosphorus for Bone Metabolism and Healthy Aging
Serna J, Bergwitz C. Importance of Dietary Phosphorus for Bone Metabolism and Healthy Aging. Nutrients 2020, 12: 3001. PMID: 33007883, PMCID: PMC7599912, DOI: 10.3390/nu12103001.Peer-Reviewed Reviews, Practice Guidelines, Standards, and Consensus StatementsConceptsDietary phosphorusReduced bioavailabilityHealthy agingHigh dietary phosphorusSources of dietary phosphorusReduced longevityAbundance of phosphorusBone metabolismWestern dietPhosphorusTissue calcificationMetabolic changesEndocrine regulationBioavailabilityNormal amountsTissueCurrent knowledgeAbundanceDifferent tissuesExcessive lossOsteomalaciaSlc20a1/Pit1 and Slc20a2/Pit2 are essential for normal skeletal myofiber function and survival
Chande S, Caballero D, Ho BB, Fetene J, Serna J, Pesta D, Nasiri A, Jurczak M, Chavkin NW, Hernando N, Giachelli CM, Wagner CA, Zeiss C, Shulman GI, Bergwitz C. Slc20a1/Pit1 and Slc20a2/Pit2 are essential for normal skeletal myofiber function and survival. Scientific Reports 2020, 10: 3069. PMID: 32080237, PMCID: PMC7033257, DOI: 10.1038/s41598-020-59430-4.Peer-Reviewed Original ResearchConceptsHyp miceMuscle functionSkeletal muscleMyofiber functionNormal body weightSkeletal muscle atrophyGene dose-dependent reductionConditional knockout miceReduced oxygen consumption rateStimulation of AMP kinaseKnockout miceHypophosphatemic disordersMuscle atrophyERK1/2 activationGrip strengthConditional deletionHormonal changesLow bloodBody weightC2C12 myoblastsMiceFurther evaluationBlood phosphateDependent reductionAMP kinase
2019
Transgenic mouse model for conditional expression of influenza hemagglutinin-tagged human SLC20A1/PIT1
Chande S, Ho B, Fetene J, Bergwitz C. Transgenic mouse model for conditional expression of influenza hemagglutinin-tagged human SLC20A1/PIT1. PLOS ONE 2019, 14: e0223052. PMID: 31613887, PMCID: PMC6793878, DOI: 10.1371/journal.pone.0223052.Peer-Reviewed Original ResearchMeSH KeywordsActinsAnimalsBeta-GlobinsBiological TransportBone DensityCalcitriolChickensCytomegalovirusFemaleFibroblast Growth Factor-23Fibroblast Growth FactorsFounder EffectHemagglutinin Glycoproteins, Influenza VirusHumansMaleMiceMice, TransgenicOsteoblastsParathyroid HormonePhosphatesPrimary Cell CulturePromoter Regions, GeneticRabbitsRecombinant Fusion ProteinsSkullTranscription Factor Pit-1TransgenesConceptsPrimary calvaria osteoblastsLoxP-stop-loxPLoxP-STOP-loxP cassetteMouse modelDihydroxy vitamin D levelsHemagglutinin (HABone mineral densityVitamin D levelsInfluenza hemagglutinin (HAConditional mouse modelActivation of transgene expressionElevated plasma PiTransgenic mouse modelPlasma iPTHUrine PiBeta-globin geneSerum calciumWT littermatesMineral densityDays of ageProtein excretionD levelsSemi-quantitative RT-PCRStandard chowTransgenic miceEndocrine regulation of MFS2 by branchless controls phosphate excretion and stone formation in Drosophila renal tubules
Rose E, Lee D, Xiao E, Zhao W, Wee M, Cohen J, Bergwitz C. Endocrine regulation of MFS2 by branchless controls phosphate excretion and stone formation in Drosophila renal tubules. Scientific Reports 2019, 9: 8798. PMID: 31217461, PMCID: PMC6584732, DOI: 10.1038/s41598-019-45269-x.Peer-Reviewed Original ResearchConceptsDrosophila renal tubulesFly life spanGenetic ablationRNAi-mediated knockdownInorganic phosphate (Pi) homeostasisHigh-Pi mediumPi transportersAdult fliesControl of FGF signalingHigher speciesPi mediumInduces expressionMFS2FGF signalingExcretion of PiPhosphate homeostasisDrosophilaFly longevityEndocrine regulationHormone fibroblast growth factor 23Renal tubulesHormonal controlPi transportFibroblast growth factor 23Genetic overexpression
2018
Role of phosphate sensing in bone and mineral metabolism
Chande S, Bergwitz C. Role of phosphate sensing in bone and mineral metabolism. Nature Reviews Endocrinology 2018, 14: 637-655. PMID: 30218014, PMCID: PMC8607960, DOI: 10.1038/s41574-018-0076-3.Peer-Reviewed Reviews, Practice Guidelines, Standards, and Consensus StatementsConceptsPi transportersSignal transductionPi homeostasisCellular phosphate homeostasisPhosphate homeostasisExpression of Pi transportersPi-sensing mechanismEssential structural componentIntracellular signal transductionPi transportMulticellular organismsInositol pyrophosphatesIntracellular Pi levelsDomain proteinsRegulation of FGF23 expressionPlasma membranePhosphate sensingDisorders of phosphate homeostasisCell metabolismExtracellular matrixCellular levelHomeostasisTransductionGenetic disordersOrganismsHereditary hypophosphatemic rickets with hypercalciuria: pathophysiology, clinical presentation, diagnosis and therapy
Bergwitz C, Miyamoto KI. Hereditary hypophosphatemic rickets with hypercalciuria: pathophysiology, clinical presentation, diagnosis and therapy. Pflügers Archiv - European Journal Of Physiology 2018, 471: 149-163. PMID: 30109410, DOI: 10.1007/s00424-018-2184-2.ChaptersConceptsElevated 1,25(OH)2D levelsHereditary hypophosphatemic ricketsHypophosphatemic ricketsActive vitamin D analoguesEnhanced intestinal calcium absorptionActive vitamin D analogsFibroblast growth factor 23Kidney stonesRare autosomal recessive disorderIntestinal calcium absorptionGrowth factor 23Risk of kidney stonesUrinary phosphate wastingDistal renal tubulesVitamin D analogsX-linked hypophosphatemiaAutosomal recessive disorderDevelopment of kidney stonesLoss-of-function mutationsSecondary hyperparathyroidismClinical presentationFactor 23Parathyroid hormoneBone lossCalcium absorption
2017
Response of Npt2a knockout mice to dietary calcium and phosphorus
Li Y, Caballero D, Ponsetto J, Chen A, Zhu C, Guo J, Demay M, Jüppner H, Bergwitz C. Response of Npt2a knockout mice to dietary calcium and phosphorus. PLOS ONE 2017, 12: e0176232. PMID: 28448530, PMCID: PMC5407772, DOI: 10.1371/journal.pone.0176232.Peer-Reviewed Original ResearchConceptsCompared to WT miceWT miceDietary calciumDietary phosphateCalcium x phosphorus productUrine phosphate levelsUrinary calcium excretionUrine anion gapDevelopment of novel therapiesWild-typeRenal stone diseaseWild-type miceNpt2a-knockout (KO) miceCalcium excretionFGF23 levelsNovel therapiesPreventing nephrolithiasisPlasma phosphateStone diseaseAnion gapAddition of calciumKnockout micePhosphorus productCalcium phosphate depositionHuman carriers
2016
Hypophosphatemia promotes lower rates of muscle ATP synthesis
Pesta DH, Tsirigotis DN, Befroy DE, Caballero D, Jurczak MJ, Rahimi Y, Cline GW, Dufour S, Birkenfeld AL, Rothman DL, Carpenter TO, Insogna K, Petersen KF, Bergwitz C, Shulman GI. Hypophosphatemia promotes lower rates of muscle ATP synthesis. The FASEB Journal 2016, 30: 3378-3387. PMID: 27338702, PMCID: PMC5024687, DOI: 10.1096/fj.201600473r.Peer-Reviewed Original ResearchConceptsMuscle ATP synthesisATP synthesisMuscle weaknessIsolated muscle mitochondriaSolute carrier familyWild-type littermate controlsSolute carrier family 34Carrier familyLower ratesInsulin-stimulated ratesMuscle mitochondriaChronic hypophosphatemiaHeart failureHypophosphatemic groupHypophosphatemic miceHypophosphatemiaLittermate controlsKnockout miceBlood PLow ratePlasma PPatientsSimilar findingsMember 1Plasma inorganic phosphate
2013
Genetic Determinants of Phosphate Response in Drosophila
Bergwitz C, Wee MJ, Sinha S, Huang J, DeRobertis C, Mensah LB, Cohen J, Friedman A, Kulkarni M, Hu Y, Vinayagam A, Schnall-Levin M, Berger B, Perkins LA, Mohr SE, Perrimon N. Genetic Determinants of Phosphate Response in Drosophila. PLOS ONE 2013, 8: e56753. PMID: 23520455, PMCID: PMC3592877, DOI: 10.1371/journal.pone.0056753.Peer-Reviewed Original ResearchConceptsLarval developmentGenome-wide RNAi screenDrosophila larval developmentGenetic determinantsImportant cellular processesNovel genetic determinantsAdult life spanLife spanExtracellular phosphate levelsD-rafRNAi-mediated inhibitionRNAi screenDrosophila melanogasterPhosphate responseCellular processesResponse to phosphateAdult fliesCandidate genesLive fliesMAPK activationAvailability of phosphateCellular responsesHigh phosphate mediumMalpighian tubulesReduced life span
2012
Roles of Major Facilitator Superfamily Transporters in Phosphate Response in Drosophila
Bergwitz C, Rasmussen MD, DeRobertis C, Wee MJ, Sinha S, Chen HH, Huang J, Perrimon N. Roles of Major Facilitator Superfamily Transporters in Phosphate Response in Drosophila. PLOS ONE 2012, 7: e31730. PMID: 22359624, PMCID: PMC3280997, DOI: 10.1371/journal.pone.0031730.Peer-Reviewed Original ResearchConceptsActivation of MAPKMajor Facilitator Superfamily (MFS) transporterDrosophila larval developmentRNAi-mediated knockdownMajor facilitator superfamily transportersPutative phosphate transportersDrosophila S2R+ cellsFacilitator superfamily transporterSodium-dependent fashionMetazoan speciesMetazoan cellsDrosophila cellsMammalian cellsPhosphate transporterLarval developmentMajor facilitatorPHO84S2R+ cellsFacilitator superfamilySuperfamily transportersMalpighian tubulesXenopus oocyte assayDrosophilaCellular effectsXenopus oocytesFGF23 and Syndromes of Abnormal Renal Phosphate Handling
Bergwitz C, Jüppner H. FGF23 and Syndromes of Abnormal Renal Phosphate Handling. Advances In Experimental Medicine And Biology 2012, 728: 41-64. PMID: 22396161, PMCID: PMC5234086, DOI: 10.1007/978-1-4614-0887-1_3.Peer-Reviewed Reviews, Practice Guidelines, Standards, and Consensus StatementsConceptsLoss-of-function mutationsParathyroid hormoneAutosomal dominant hypophosphatemic ricketsDentin matrix protein 1Ecto-nucleotide pyrophosphatase/phosphodiesterase 1O-glycosylation of FGF23Hypophosphatemic ricketsAbnormal renal phosphate handlingImpaired O-glycosylationFibroblast growth factor 23Hormonal bone-parathyroid-kidney axisGrowth factor 23Serum phosphate levelsRenal phosphate excretionRenal phosphate handlingFamilial hyperphosphatemic tumoral calcinosisSodium-phosphate cotransporters NaPi-IIaHereditary hypophosphatemic ricketsHyperphosphatemic tumoral calcinosisIncreased serum phosphate levelsFunction mutationsPhosphate-regulating geneRare genetic disorderCotransporter NaPi-IIaDominant hypophosphatemic rickets
2011
Case 33-2011 — A 56-Year-Old Man with Hypophosphatemia
Bergwitz C, Collins MT, Kamath RS, Rosenberg AE. Case 33-2011 — A 56-Year-Old Man with Hypophosphatemia. New England Journal Of Medicine 2011, 365: 1625-1635. PMID: 22029985, PMCID: PMC4907641, DOI: 10.1056/nejmcpc1104567.Peer-Reviewed Original ResearchPhosphate Sensing
Bergwitz C, Jüppner H. Phosphate Sensing. Advances In Kidney Disease And Health 2011, 18: 132-144. PMID: 21406298, PMCID: PMC3059779, DOI: 10.1053/j.ackd.2011.01.004.Peer-Reviewed Reviews, Practice Guidelines, Standards, and Consensus StatementsConceptsAmino acid sequence conservationNumerous cellular functionsMulti-protein complexesDifferent signal transduction cascadesSignal transduction cascadeExpression of genesSignal transduction cascadesEukaryotic organismsMulticellular organismsMetazoan cellsMetazoan orthologsSequence conservationCellular functionsPHO pathwayTransduction cascadePlasma membraneAmbient phosphateCell metabolismExtracellular phosphateYeastGrowth of tissuesPhosphate sensorPhosphate homeostasisPhosphate uptakeCirculating phosphate levels
2010
Regulation of Phosphate Homeostasis by PTH, Vitamin D, and FGF23
Bergwitz C, Jüppner H. Regulation of Phosphate Homeostasis by PTH, Vitamin D, and FGF23. Annual Review Of Medicine 2010, 61: 91-104. PMID: 20059333, PMCID: PMC4777331, DOI: 10.1146/annurev.med.051308.111339.Peer-Reviewed Reviews, Practice Guidelines, Standards, and Consensus StatementsConceptsParathyroid hormoneDentin matrix protein 1Regulation of phosphate homeostasisVitamin DPhosphate homeostasisFibroblast growth factor 23Serum phosphorus levelsGrowth factor 23Renal phosphate excretionSecretion of FGF23Secretion of parathyroid hormoneSodium-phosphate cotransporters NaPi-IIaCotransporter NaPi-IIaIncreases renal phosphate excretionGenetically engineered miceRegulation of calcium homeostasisHomologies to endopeptidasesKidney axisMatrix protein 1Sodium-phosphate cotransporter NaPi-IIaFactor 23Serum phosphorusPhosphate excretionParathyroid glandsHormonal bone-parathyroid-kidney axis
2009
Disorders of Phosphate Homeostasis and Tissue Mineralisation
Bergwitz C, Jüppner H. Disorders of Phosphate Homeostasis and Tissue Mineralisation. Endocrine Development 2009, 16: 133-156. PMID: 19494665, PMCID: PMC3810012, DOI: 10.1159/000223693.Peer-Reviewed Reviews, Practice Guidelines, Standards, and Consensus StatementsConceptsDisorders of phosphate homeostasisPhosphate homeostasisFibroblast growth factor 23Secretion of parathyroid hormoneAbnormal phosphate homeostasisDentin matrix protein 1Tissue mineralizationGrowth factor 23Co-receptor KlothoBone-kidney axisReabsorption of phosphateExpression of FGF23Renal proximal tubulesHomologies to endopeptidasesMatrix protein 1Phosphate-regulating geneCirculating phosphate concentrationClinical presentationFactor 23Parathyroid hormoneUDP-N-acetyl-alpha-D-galactosamineParathyroid glandsDiagnostic evaluationProximal tubulesD-galactosamine
2008
Genetic Evidence of Serum Phosphate-Independent Functions of FGF-23 on Bone
Sitara D, Kim S, Razzaque MS, Bergwitz C, Taguchi T, Schüler C, Erben RG, Lanske B. Genetic Evidence of Serum Phosphate-Independent Functions of FGF-23 on Bone. PLOS Genetics 2008, 4: e1000154. PMID: 18688277, PMCID: PMC2483943, DOI: 10.1371/journal.pgen.1000154.Peer-Reviewed Original ResearchMeSH KeywordsAnimalsBone and BonesBone DensityCalcification, PhysiologicCells, CulturedFibroblast Growth Factor-23Fibroblast Growth FactorsGene ExpressionHypophosphatemiaMiceMice, Inbred C57BLMice, KnockoutMuscle, SkeletalOsteoblastsPhenotypePhosphatesSerumSkullSodium-Phosphate Cotransporter Proteins, Type IIaUrineConceptsFGF-23 geneFgf-23-/- micePhosphate homeostasisGenetic evidenceFgf-23-/-Regulation of phosphate homeostasisCrucial biological importanceFirst genetic evidenceSystemic phosphate homeostasisSkeletal mineralizationCellular functionsDouble mutantNew mouse lineMaster regulatorProtein abundanceGenomic ablationMolecular mechanismsDouble mutant miceChondrocyte differentiationTargeted disruptionSkeletal phenotypeBiological importanceGenesEnergy metabolismHomeostasisA novel missense mutation in SLC34A3 that causes hereditary hypophosphatemic rickets with hypercalciuria in humans identifies threonine 137 as an important determinant of sodium-phosphate cotransport in NaPi-IIc
Jaureguiberry G, Carpenter TO, Forman S, Jüppner H, Bergwitz C. A novel missense mutation in SLC34A3 that causes hereditary hypophosphatemic rickets with hypercalciuria in humans identifies threonine 137 as an important determinant of sodium-phosphate cotransport in NaPi-IIc. American Journal Of Physiology. Renal Physiology 2008, 295: f371-f379. PMID: 18480181, PMCID: PMC2519180, DOI: 10.1152/ajprenal.00090.2008.Peer-Reviewed Original ResearchMeSH KeywordsAdultAllelesAnimalsBase SequenceExocytosisFamilial Hypophosphatemic RicketsFemaleHaplotypesHumansHypercalciuriaKidneyMaleMolecular Sequence DataMutation, MissenseOocytesOpossumsPhosphatesPolymorphism, Single NucleotideSodiumSodium-Phosphate Cotransporter ProteinsSodium-Phosphate Cotransporter Proteins, Type IIcThreonineXenopus laevisConceptsEncoding enhanced green fluorescent proteinHereditary hypophosphatemic ricketsNaPi-IIcSodium-phosphate cotransporterLoss of expressionAmino acid residuesSodium-phosphate cotransportGreen fluorescence proteinImportant functional roleComplete lossOpossum kidneyHypophosphatemic ricketsXenopus laevis oocytesNovel missense mutationPaternal alleleWild-typeFunctional analysisFluorescence proteinNH2 terminusAcid residuesApical patchesCompound heterozygous mutationsExpression plasmidFunctional roleRecurrent kidney stones
2005
SLC34A3 Mutations in Patients with Hereditary Hypophosphatemic Rickets with Hypercalciuria Predict a Key Role for the Sodium-Phosphate Cotransporter NaPi-IIc in Maintaining Phosphate Homeostasis
Bergwitz C, Roslin NM, Tieder M, Loredo-Osti JC, Bastepe M, Abu-Zahra H, Frappier D, Burkett K, Carpenter TO, Anderson D, Garabédian M, Sermet I, Fujiwara TM, Morgan K, Tenenhouse HS, Jüppner H. SLC34A3 Mutations in Patients with Hereditary Hypophosphatemic Rickets with Hypercalciuria Predict a Key Role for the Sodium-Phosphate Cotransporter NaPi-IIc in Maintaining Phosphate Homeostasis. American Journal Of Human Genetics 2005, 78: 179-192. PMID: 16358214, PMCID: PMC1380228, DOI: 10.1086/499409.Peer-Reviewed Original ResearchConceptsConsanguineous BedouinFirst membrane-spanning domainMembrane-spanning domainsPhosphate homeostasisRenal sodium-phosphate cotransporterNucleotide sequence analysisDihydroxyvitamin D levelsSingle nucleotide deletionHereditary hypophosphatemic ricketsCompound heterozygous missenseSLC34A3 mutationsHomozygous single nucleotide deletionHypophosphatemic ricketsLinkage scanCandidate genesGenomic DNASodium-phosphate cotransporterSequence analysisD levelsHomozygosity mappingDeletion mutationsGenomewide linkage scanKey roleChromosome 9q34Mutations