Tetrahydrocannabinolic Acid a (THCA-A) Reduces Adiposity and Prevents Metabolic Disease Caused by Diet-Induced Obesity

Cannabis has remarkable therapeutic potential, but its clinical use is limited by the psychotropic activity of {Delta}9-tetrahydrocannabinol ({Delta}9-THC). Surprisingly, the biological profile of the non-narcotic native precursor of {Delta}9-THC ({Delta}9-THC acid A, {Delta}9-THCA-A) is still largely unexplored. We present evidence that {Delta}9-THCA-A is a partial and selective PPAR{gamma} modulator, endowed with lower adipogenic activity than the full PPAR{gamma} agonist rosiglitazone (RGZ) and with an enhanced osteoblastogenic activity in human mesenchymal stem cells. Docking and in vitro functional assays indicated that {Delta}9-THCA-A binds to and activates PPAR{gamma} by acting at both the canonical and the alternative sites of the ligand-binding domain. Transcriptomic signatures at inguinal white adipose tissue (iWAT) from mice treated with {Delta}9-THCA-A confirmed its mode of action on PPAR{gamma}. Administration of {Delta}9-THCA-A in a mouse model of high fat diet (HFD)-induced obesity significantly reduced fat mass and body weight gain, markedly ameliorating glucose intolerance and insulin resistance, and largely preventing liver steatosis, adipogenesis and macrophage infiltration in fat tissues. Additionally, immunohistochemistry, transcriptomic, and plasma biomarker analyses showed that treatment with {Delta}9-THCA-A caused browning of iWAT and displayed potent anti-inflammatory actions in HFD mice. Altogether, our data validate the potential of {Delta}9-THCA-A as a low adipogenic PPAR{gamma} agonist, capable of substantially improving the symptoms of obesity-associated metabolic syndrome and inflammation. These findings suggest that {Delta}9-THCA-A, and perhaps non-decarboxylated Cannabis sativa extracts, are worth considering for addition to our inventory of cannabis medicines.nnSIGNIFICANCE STATEMENTThe medicinal use of Cannabis is gaining momentum, despite the adverse psychotropic effects of {Delta}9-THC, the decarboxylation product of its naturally occurring and non-psychotropic precursor {Delta}9-THCA-A. We present evidence that {Delta}9-THCA-A is a partial ligand agonist of PPAR{gamma} with lower adipogenic activity compared to the full PPAR{gamma} agonist rosiglitazone (RGZ). Moreover, chronic administration of {Delta}9-THCA-A in a mouse model of high fat diet (HFD)-induced obesity significantly reduced body weight gain and fat mass, improved glucose intolerance and insulin resistance, and prevented liver steatosis and macrophage infiltration in fat tissues, additionally inducing white adipose tissue browning. Collectively, these observations qualify {Delta}9-THCA-A, a compound devoid of psychotropic effects, as an efficacious pharmacological agent to manage metabolic syndrome and obesity-associated inflammation.nnHighlights- {Delta}9-THCA-A is a partial PPAR{gamma} ligand agonist with low adipogenic activityn- {Delta}9-THCA-A enhances osteoblastogenesis in bone marrow derived mesenchymal stem cells.n- {Delta}9-THCA-A reduces body weight gain, fat mass, and liver steatosis in HFD-fed micen- {Delta}9-THCA-A improves glucose tolerance, insulin sensitivity, and insulin profiles in vivon- {Delta}9-THCA-A induces browning of iWAT and has a potent anti-inflammatory activity