
Type:Protein
SpeciesReactivity:H
B=Bovine;Ca=Cat;Ch=Chicken;D=Dog;EQ=Equine;GP=GuineaPig;H=Human;M=Mouse;P=Porcine;Pr=Primate;R=Rat;Rb=Rabbit;Y=Yeast;Xe=Xenopus;Ze=Zebrafish;;;;NA-NotApplicable;STP=Step-TactinProteins;AllVisfatin,alsoknownaspre-Bcellcolony-enhancingfactor(PBEF),isacytokinethatishighlyexpressedinvisceralfatandwasoriginallyisolatedasasecretedfactorthatsynergizeswithIL-7andstemcellfactorstopromotethegrowthofBcellprecursors.Visfatinhomologshavebeenidentifiedincarp,invertebratemollusks,andbacteria,aswellasinvertebrates,includinghumansandthemouse.Ithasbeenpostulatedtoplayaroleininnateimmunity.
Visfatinexertsinsulin-mimeticeffectsthataredose-dependentandquantitativelysimilartothoseofinsulininstimulatingmuscleandADIpocyteglucosetransport,andininhibitinghepatocyteglucoseproduction.Intravenousinjectionofrecombinantvisfatininmicedecreasedplasmaglucoseinadose-dependentfashion.Inkeepingwithitsinsulin-mimeticeffects,visfatinwasaseffectiveasinsulininreducinghyperglycemiaininsulin-deficientdiabeticmice.Visfatinwasalsofoundtobeboundtoandactivateinsulinreceptor,causingreceptorphosphorylationandtheactivationofdownstreamsignalingmolecules.However,visfatinandinsulindidnotcompeteforbindingtotheinsulinreceptor,indicatingthatthetwoproteinswererecognizedbydifferentregionsofthereceptor.Thus,visfatinmightplayaroleinglucosehomeostasisanddysregulationinbiosynthesisorsignaltransduction,andmightcontributetothepathogenesisofdiabetes.