Recombinant Human Visfatin

Visfatin, also known as a pre-B cell colony-enhancing factor, is an adipocyte hormone with a direct relationship between plasma visfatin levels and type 2 diabetes mellitus. Visfatin causes hypoglycaemia by reducing glucose release from liver cells and stimulating glucose utilization in adipocytes and myocytes. Visfatin is upregulated by hypoxia, inflammation and hyperglycaemia and downregulated by insulin, somatostatin and statins. This hormone is found in the cytoplasm as well as the nucleus of cells and has been identified in many tissues and organs including the brain, kidney, lung, spleen and testis but preferentially expressed in visceral adipose tissue. Visfatin is an endocrine, autocrine as well as paracrine peptide with many functions including enhancement of cell proliferation, biosynthesis of nicotinamide mono- and dinucleotide and hypoglycaemic effect.¹ Visfatin may represent a novel link between inflammation and adipocytokines among long-term kidney transplant recipients.²

The biological activity of Human Visfatin is determined by the dose-dependant proliferation of the RPMI 8226 cells. The expected ED₅₀ for this effect is 15.0-20.0 ng/ml.

MPPNTSKVYS YFECREKKTE NSKLRKVKYE ETVFYGLQYI LNKYLKGKVV TKEKIQEAKD VYKEHFQDDV FNEKGWNYIL EKYDGHLPIE IKAVPEGFVI PRGNVLFTVE NTDPECYWLT NWIETILVQS WYPITVATNS REQKKILAKY LLETSGNLDG LEYKLHDFGY RGVSSQETAG IGASAHLVNF KGTDTVAGLA LIKKYYGTKD PVPGYSVPAA EHSTITAWGK DHEKDAFEHI VTQFSSVPVS VVSDSYDIYN ACEKIWGEDL RHLIVSRSTQ APLIIRPDSG NPLDTVLKVL EILGKKFPVT ENSKGYKLLP PYLRVIQGDG VDINTLQEIV EGMKQKMWSI ENIAFGSGGG LLQKLTRDLL NCSFKCSYVV TNGLGINVFK DPVADPNKRS KKGRLSLHRT PAGNFVTLEE GKGDLEEYGQ DLLHTVFKNG KVTKSYSFDE IRKNAQLNIE LEAAHH

The lyophilized protein should be stored desiccated at -20°C. The reconstituted protein can be stored for at least one week at 4°C. For long-term storage of the reconstituted protein, aliquot into working volumes and store at -20°C in a manual defrost freezer. Avoid Repeated Freeze Thaw Cycles.

1. Adeghate E et al. (2008) Curr Med Chem. 15: 1851 2. Mysliwiec M et al. (2009) Transplant Proc. 41: 150