Investigation of cytotoxic and apoptotic effects of 63 compounds obtained from Salvia species: Promising anticancer agents

Abstract

Since ancient time, Salvia L. species have been commonly used to treat colds, bronchitis, tuberculosis, heart diseases, and menstrual and digestive disorders in traditional medicine all around the world. They have been also used as tea and spice. Studies indicated that diterpenes and triterpenes isolated from Salvia species possess various pharmacological and biological effects such as anti-inflammatory, antiviral, cytotoxic, antioxidant, and hepatotoxic activities. Flavones were also shown to have antimicrobial, antioxidant, and cytotoxic potentials. Salvia extracts also exhibit anti-Alzheimer, antiseptic, cardiovascular, antihypertensive, and antituberculous effects. To investigate the effects of 63 secondary metabolites from Salvia species on cell viability and apoptosis, Salvia secondary metabolites including 25 phenolics, 4 fatty acids, 19 abietane diterpenoids, 12 triterpenoids, and three steroids were examined on healthy cell line (PDF), breast cancer (MCF-7), and colon cancer (HT-29) cell lines using MTT method. In addition, the effects of rosmarinic acid, 6,7-dehydroroyleanone, acetyl royleanone, ferruginol, carnosic acid, carnosol, cryptotanshinone, beta-sitosterol, and ursolic acid on pro-apoptotic Bax and antiapoptotic Bcl-2 protein expression levels were investigated by Western Blot method. Practical applications Phenolic compounds (apigenin, chrysin, and luteolin) and diterpenes (especially dihydrotanshinone I, carnosic acid, and carnosol), and almost all of the triterpenes exhibited high toxic effects on healthy cell line. Cytotoxic effects of cryptotanshinone, 12-hydroxy abieta-1,3,5(10),8,11,13-hexaene, 12-demethylmulticauline, 6,7-dehydroroyleanone, acetyl royleanone, ferruginol, ursolic acid, and 3-acetyl lupeol were relatively higher than their toxic effects. Acetyl royleanone, 6,7-dehydroroyleanone, carnosic acid, and cryptotanshinone were found to have anticancer potential based on their modulating effects on the expression levels of Bax and Bcl-2 proteins which play important roles in the regulation of apoptosis. The results of the present study showed that acetyl royleanone, cryptotanshinone, 6,7-dehydroroyleanone, carnosic acid, and cryptotanshinone have potential to be used in the pharmaceutical industry.