Coleus forskohlii belongs to the family Labiatae (Lamiaceae), which includes flavorful herbs such as mints and lavenders. Preparations of C. forskohlii have been used in traditional Ayurvedic medicine to treat a variety of conditions including heart disease, respiratory disorders and insomnia.
C. forskohlii is the only known natural source of forskohlin, a compound which activates adenylate cyclase1.
Extracts from this herb were shown to increase the levels of cyclic adenosine monophosphate (cAMP) in smooth muscle, including heart and bronchial muscle. In the heart, this leads to relaxation of muscle and modulation of rhythm, with simultaneous enhancement of circulation. These findings may validate the use of C. forskohlii extract as a cardio- and bronchotonic.
An interesting in vivo study reported that C. forskohlii extract improved the utilization of insulin. This indicates that the extract may also have a role to play in the management of adult onset diabetes. Additionally, studies in rabbits revealed that topical application of forskohlin decreased intraocular pressure. Increased intraocular pressure in the eye is a causative factor of glaucoma.
Due to its effects on CAMP, forskohlin may influence lipid metabolism and have a potential role in weight loss. Forskohlin has also been shown to stimulate thyroid hormone secretions.
References:
- Recent Advances in Medicinal, Aromatic & Spice Crops (1991). 1: 83-91>
- Planta Medica (I 985). 59: 37