NAMPT is essential for the G-CSF-induced myeloid differentiation via a NAD(+)-sirtuin-1-dependent pathway.

We identified nicotinamide phosphoribosyltransferase (NAMPT), also known as pre-B cell colony enhancing factor (PBEF), as an essential enzyme mediating granulocyte colony-stimulating factor (G-CSF)-triggered granulopoiesis in healthy individuals and in individuals with severe congenital neutropenia. Intracellular NAMPT and NAD(+) amounts in myeloid cells, as well as plasma NAMPT and NAD(+) levels, were increased by G-CSF treatment of both healthy volunteers and individuals with congenital neutropenia. NAMPT administered both extracellularly and intracellularly induced granulocytic differentiation of CD34(+) hematopoietic progenitor cells and of the promyelocytic leukemia cell line HL-60.

Neuronal NO synthase and its inhibitor PIN are present and influenced by glucose in the human beta-cell line CM and in rat INS-1 cells.

Nitric oxide (NO) is synthesised by different nitric oxide synthases (NOS) from L-arginine and acts as a signal transducer in a variety of cells. The neuronal isoenzyme of NOS (nNOS) was recently found in rodent beta-cells and beta-cell lines. We provide evidence that nNOS is also present in the human beta-cell line CM and that the specific inhibitor of nNOS PIN is expressed in CM and INS-1 cells.