A synthetic cannabinoid pharmaceutical called Rimonabant was briefly approved in Europe as an anti-obesity drug. Rimonabant inhibits the CB1 receptor, reducing its activity below normal levels and blocking other compounds, like THC or anandamide, from activating it. It was taken off the market in 2008 for causing suicidal thoughts, among other psychiatric problems, which occurred when this pharmaceutical shut down cannabinoid activity in parts of the brain. Rimonabant is still a common tool for researchers studying the effect of CB1 inhibition, particularly in regard to obesity. A new study from scientists at the University of South Carolina described how CB1 inhibition by Rimonabant leads to changes in gene regulation, and a subsequent anti-obesity effect. The drug alters the level of immune-regulating microRNAs, which interfere with the ability of cells to make proteins from DNA, the universal genetic code. This mutes the effects of certain inflammatory genes, skewing immune cells to an anti-inflammatory state.