Mechanism of Toona sinensis-stimulated adrenal steroidogenesis in primary rat adrenal cells. (April 2015)

• Record Type: Journal Article
• Authors: Chen, Yung-Chia; Liang, Yi-Lin; Huang, Yuan-Li; Huang, Bu-Miin
• Is Part Of: Journal of functional foods. Volume 14(2015)
• Page Start: 318
• Page End: 323
• Publication Date: 2015-04
• Subjects: Toona sinensis -- adrenal cell -- steroidogenesis; dbcAMP dibutyryladenosine-3′-5′ cyclic monophosphate -- DOC deoxycorticosterone -- EIA enzyme immunoassay -- fsk forskolin -- StAR steroidogenic acute regulatory protein -- TSL-1 aqueous leaf extracts of Toona sinensis -- preg pregnenolone -- prog progesterone; Gallic acid (PubChem CID: 370) -- Methyl gallate (PubChem CID: 7428) -- Ethyl gallate (PubChem CID: 13250) -- Kaempferol (PubChem CID: 5280863); Functional foods -- Analysis -- Periodicals; Food -- Biotechnology -- Periodicals; Nutrition -- Periodicals; 613.2
• DOI: 10.1016/j.jff.2015.02.012
• Languages: English
• ISSNs: 1756-4646

Abstract

Highlights: Aqueous leaf extracts of T. sinensis (TSL-1) stimulates adrenal steroidogenesis. TSL-1 induces adrenal steroidogenesis through cAMP-dependent PKA pathway. Activity of steroidogenic enzymes are involved in TSL-1-induced corticosterone production. TSL-1 induces StAR mRNA and protein expression as well as StAR promoter activity. Abstract: Toona sinensis is a well-known nutritious plant food widely distributed in Asia. The effects of aqueous leaf extracts of T. sinensis (TSL-1) on steroidogenesis was examined using primary rat adrenal cells. TSL-1 stimulated corticosterone production in a time- and concentration-dependent manner. Cells were then challenged with forskolin, dibutyryl cyclic AMP (dbcAMP), pregnenolone, progesterone or deoxycorticosterone in the presence or absence of TSL-1 for 6 h to determine the mechanism. TSL-1 could enhance forskolin- and dbcAMP-induced steroidogenesis and promote pregnenolone-, progesterone- and deoxycorticosterone-induced steroidogenesis. Moreover, TSL-1 induced steroidogenic acute regulatory protein (StAR) mRNA and protein expression in rat adrenal cells and increased StAR promoter activity in CHO-K1 cells. Thus, the stimulatory effect of TSL-1 was presumed to be mainly due to methyl and ethyl gallates. Therefore, TSL-1-stimulated corticosterone production requires the participation of cAMP-dependent PKA, steroidogenic enzymes and the expression of StAR, which regulates the rate-limiting step in steroidogenesis.