Monocrotaline is an 11-membered macrocyclic pyrrolizidine alkaloid derived from the seeds of the Crotalaria spectabilis plant. Monocrotaline is activated to the reactive pyrrole metabolite dehydromonocrotaline in the liver, a reaction that is highly dependent on cytochrome P-450 (CYP3A4). Monocrotaline induces a syndrome characterized, among other manifestations, by pulmonary hypertension, pulmonary mononuclear vasculitis (acute necrotizing pulmonary arteritis in about one-third of the animals), and right ventricular hypertrophy. Monocrotaline is widely used to model pulmonary arterial hypertension in rodents. Monocrotaline aggregates on and activates the extracellular calcium-sensing receptor (CaSR) of pulmonary artery endothelial cells to trigger endothelial damage and, ultimately, induces pulmonary hypertension.

Dehydroabietic acid (DHA or DAA), a diterpene, is obtained from Commiphora oppbalsamum. DHA has potential as treatment for obesity and metabolic syndrome, obese diabetic KK-Ay mice treated with DHA showed decreased plasma glucose, insulin, and triglyceride levels. It has been reported that DHA inhibits the production of proinfammatory mediators such as TNF-α in macrophages and adipocytes and causes endothelium-dependent relaxation of pulmonary artery via PI3K/Akt-eNOS signaling pathway. Also was shown, that DHA could reverse several cell responses stimulated by TNF-α, including the activation of FOXO1 and the TGF-β1/Smad3 signaling pathway. Thus, DAA could be useful in improving the diabetic wound healing.