Background Nesfatin-1 is a recently identified satiety-inducing adipokine determined in hypothalamic regions that regulates energy balance . It is an integral regulator of energy homeostasis and a putative glucose-dependent insulin coadjuvant . Nesfatin-1 has strong similarities in terms of metabolic actions with other members of adipokine superfamily, such as leptin, adiponectin and lipocalin-2. These factors have been recently identified as active players in the regulation of physiological and pathological processes, such as inflammation and immune response in whole joint tissues and in rheumatic diseases, such as osteoarthritis (OA) and/or rheumatoid arthritis (RA).
Objectives So far, no data exist on nesfatin expression, regulation, and secretion in human and murine chondrocytes. We therefore investigated NUCB2/nesfatin-1 gene and protein expression in human and murine chondrocytes. For completeness, the effect of NUCB-2 on pro-inflammatory cytokines expression was also studied
Methods NUCB-2 mRNA expression was studied by qRT-PCR. Protein secretion was measured by BioPlex assay and Western blot analysis. Peptide localization was performed by laser confocal microscopy.
Results First, we demonstrated cytoplasmic localization of NUCB-2 peptide in both human and murine chondrocytes. We present evidence that both mRNA and protein expression of NUCB-2 were increased during the differentiation of ATDC5 murine chondrocyte cell line Furthermore, we demonstrated that nesfatin-1 induces IL-6 and MIP-1α mRNA expression and protein secretion in ATDC5 cells challenged with IL-1. Finally, nesfatin-1 provoked a clear and a direct induction of pro-inflammatory agents, such as COX-2 and IL-8 in human chondrocytes.
Conclusions NUCB-2/Nesfatin-1 is synthesized and produced by human and murine chondrocytes, in which it exerts a clear pro-inflammatory activity.
Oh-I S, Shimizu H, Satoh T, Okada S, 2006 Identification of nesfatin-1 as a satiety molecule in the hypothalamus. Nature 443:709-71
Ramanjaneya M, Chen J, Brown JE, Tripathi G, 2010 Identification of nesfatin-1 in human and murine adipose tissue: a novel depot-specific adipokine with increased levels in obesity. Endocrinology 151(7):3169-80
Disclosure of Interest None Declared