Sinapic and ferulic acid phenethyl esters increase the expression of steroidogenic genes in MA-10 tumor Leydig cells.

During aging, the production of androgens by the testis Leydig cells gradually decreases. Phenolic compounds can improve testosterone biosynthesis and delay the onset of hypogonadal symptoms in males. In this study, sinapic acid phenethyl ester was evaluated for its ability to regulate gene expression and steroid production in Leydig cells. Specifically, the effects of this ester on the transcriptome of MA-10 Leydig cells were investigated by RNA-Seq. To better establish a structure-function relationship of the hydroxy-methoxyphenyl moiety of sinapic and phenethyl ester, its influences on gene expression were compared to those of its ferulic acid phenethyl ester analogue. According to the transcriptomic analysis, most genes encoding enzymes related to cholesterol biosynthesis are increased in response to sinapic acid phenethyl ester treatment of MA-10 Leydig cells. Interestingly, treatments with 10 µM of ferulic acid phenethyl ester increased cAMP-dependent Star promoter activation, gene expression and protein levels. In addition, treatments of MA-10 Leydig cells with 10 µM of sinapic or ferulic acid phenethyl ester resulted in increased progesterone production. Thus, our results indicate that sinapic and ferulic acid phenethyl esters can improve cholesterol and steroid biosynthesis in testicular Leydig cells.

Gigantol Improves Cholesterol Metabolism and Progesterone Biosynthesis in MA-10 Leydig Cells.

In aging males, androgen production by testicular Leydig cells decreases at a rate of approximately 1% per year. Phenolic compounds may enhance testosterone biosynthesis and delay the onset of male hypogonadism. Gigantol is a bibenzyl compound isolated from several types of orchids of the genus Dendrobium. This compound has various biological activities, including antioxidant activity. However, its capacity to regulate gene expression and steroid production in testicular Leydig cells has never been evaluated. We investigated the effect of gigantol on MA-10 Leydig cells' gene expression using an RNA-Seq approach. To further investigate the structure-function relationship of the hydroxy-methoxyphenyl moiety of gigantol, experiments were also performed with ferulic acid and isoferulic acid. According to transcriptomic analysis, all genes coding for cholesterol biosynthesis-related enzymes are increased in response to gigantol treatment, resulting in increased lipid droplets accumulation. Moreover, treatments with 10 µM gigantol increased StAR protein levels and progesterone production from MA-10 Leydig cells. However, neither ferulic acid nor isoferulic acid influenced StAR protein synthesis and progesterone production in MA-10 Leydig cells. Thus, our findings indicate that gigantol improves cholesterol and steroid biosynthesis within testicular Leydig cells.