What is visfatin?

Scientists continue to debate the validity of a highly-cited, controversial 2004 Science paper about a new fat cell protein with insulin-mimetic properties.Last week, Osaka University, which hosted the research, demanded that the researchers retract the paper. In the contested study, Iichiro Shimomura and colleagues at Osaka University Graduate School of Medicine identified a new protein, visfatin, in fat cells and reported that it had insulin-mimetic properties. They found that visfatin lowered blood glucose in vivo in mice and promoted glucose uptake in vitro. Visfatin, the researchers found, is present in visceral adipose tissue, and circulating levels of the protein correlated with fat mass in humans, which raised the possibility of this protein as a potential drug target for type 2 diabetes and other metabolic disorders, the authors wrote. But further research in humans has cast doubt on visfatin as a potential therapy. In the 2004 article, Shimomura and colleagues...