2-NBDG is a fluorescent tracer used for monitoring glucose uptake into living cells; it consists of a glucosaminemolecule substituted with a 7-nitrobenzofurazan fluorophore at its amine group. It is widely referred to a fluorescent derivative of glucose,[1] and it is used in cell biology to visualize uptake of glucose by cells.[2] Cells that have taken up the compound fluoresce green.
2-NBDG is similar to radiolabeled glucose in that both can be used to detect glucose transport. Unlike radiolabeled glucose, 2-NBDG is compatible with fluorescence techniques such as a fluorescent microscopy, flow cytometry, and fluorimetry.[2]
The compound is taken up by a variety of mammalian, plant, and microbial cells[2][3][4] In bacterial cells, the predominant transporter is the mannosephosphotransferase system.[4] Cells that lack these or other compatible transporters do not take up 2-NBDG.[4][5] In mammalian cells, one transporter for 2-NBDG is GLUT2.[6] In T cells, 2-NBDG was transported by another, unidentified transporter and it did not match radiolabeled glucose transport.[7]
Like glucose, 2-NBDG is transported according to Michaelis–Menten kinetics. However, transport of 2-NBDG has a lower Vmax (maximum rate), and thus the rate of transport is generally slower than glucose.[4]
Once taken up, the compound is metabolized to a non-fluorescent derivative, as shown in Escherichia coli.[8] The identity and further metabolism of this non-fluorescent derivative has not been established.
References
^Yoshioka K, Takahashi H, Homma T, Saito M, Oh K, Nemoto Y, Matsuoka H (1996). "A novel fluorescent derivative of glucose applicable to the assessment of glucose uptake activity of Escherichia coli". Biochim Biophys Acta. 1289 (1): 5–9. doi:10.1016/0304-4165(95)00153-0. PMID8605231.
^ abcYamada K, Saito M, Matsuoka H, Inagaki N (2007). "A real-time method of imaging glucose uptake in single, living mammalian cells". Nat Protoc. 2 (3): 753–62. doi:10.1038/nprot.2007.76. PMID17406637. S2CID22801727.
^Chang HC, Yang SF, Huang CC, Lin TS, Liang PH, Lin CJ, Hsu LC (2013). "Development of a novel non-radioactive cell-based method for the screening of SGLT1 and SGLT2 inhibitors using 1-NBDG". Mol Biosyst. 9 (8): 2010–20. doi:10.1039/c3mb70060g. PMID23657801.
^Yoshioka K, Saito M, Oh KB, Nemoto Y, Matsuoka H, Natsume M, Abe H (1996). "Intracellular fate of 2-NBDG, a fluorescent probe for glucose uptake activity, in Escherichia coli cells". Biosci. Biotechnol. Biochem. 60 (11): 1899–901. doi:10.1271/bbb.60.1899. PMID8987871.