Peroxisome proliferator-activated receptor gamma (PPARγ)

Peroxisome proliferator-activated receptor gamma, or PPAR-gamma, is a receptor inside the cell nucleus that controls genes for fat storage, insulin sensitivity and inflammation.

Unlike surface receptors, PPAR-gamma is a transcription factor: when a fatty acid or related lipid binds it, it pairs with the retinoid X receptor, attaches to DNA and switches specific genes on or off. It is most abundant in fat tissue, where it directs the formation of new fat cells, and it is also active in macrophages, gut lining and the brain, where it restrains inflammatory gene programs. The diabetes drugs pioglitazone and rosiglitazone work by activating it, which improves insulin sensitivity but can also cause fluid retention and weight gain.

The receptor belongs in a cannabinoid glossary because it is one of the non-cannabinoid targets at which CBD has measurable activity in laboratory systems, and PPAR-gamma activation has been proposed to explain some of the anti-inflammatory and neuroprotective findings in cell and animal experiments. That mechanism has not been confirmed in people.