Tetrahydropiperine (Cosmoperine) is a natural product derived from piperine, can be used to treat convulsion, epilepsy, relieve pain, and control insects.

MOCD:25 µM, CYP450:23 µM , TRPV1:6.3 µM

The test compounds were PIP [5-(3,4-methylenedioxyphenyl)-2,4-pentadienoylpiperidine], tetrahydropiperine [THP, 5-(3,4-methylenedioxyphenyl)-pentanoylpiperidine], a cyclohexyl analogue of piperine [CHP, 5-(3,4-methylenedioxyphenyl)-2,4-pentadienoylcyclohexylamine], and reduced CHP [rCHP, 5-(3,4-methylenedioxyphenyl)-2,4-pentanoylcyclohexylamine].?Sparsely pigmented, HRA/Skh-II mice were randomized to receive topical treatment with test compounds or vehicle twice a day for five days a week, with or without ultraviolet (UV) irradiation on 3 days a week.?Treatment was either continuous or interrupted to evaluate fading and repigmentation.?Skin inflammation and pigmentation were evaluated regularly during treatment.?DOPA+ melanocytes were determined histologically at the termination of treatment[3].