The effects of Tremella aurantia on testosterone and corticosterone productions in normal and diabetic rats

Tremella aurantia (TA) has been traditionally used as food and crude medicine in Chinese society. The polysaccharide isolated from the fruiting bodies of TA exhibits significant hypoglycemic activity in diabetic mouse models of insulin-dependent diabetes mellitus (IDDM) and non-insulin-dependent diabetes mellitus (NIDDM). Diabetes will cause sexual dysfunction in patients. In the present study, we examined if the treatment of TA on IDDM and NIDDM rats will restore steroidogenesis and then the reproductive function. The fruiting bodies (FB), mycelium (TM) and polysaccharide (GX) of TA were fed to the IDDM and NIDDM rats, and testosterone and corticosterone levels in plasma, the weight of steroidogenic organs, and the expression of steroidogenic acute regulatory (StAR) protein and P450scc enzyme were determined. Plasma testosterone productions were significantly suppressed with the feeding of FB or TM in normal rat (p < 0.05). Testosterone productions were also significantly suppressed in IDDM diabetes rats (p < 0.05), and FB or TM could not restore the inhibitory effects (p > 0.05). There was no significant difference of the testosterone production between normal and NIDDM rats (p, > 0.05). In plasma corticosterone production, there were no differences among control, FB- or TM-fed normal rats (p > 0.05). Corticosterone levels were reduced in IDDM rats compared to control, and FB or TM could restore its level. Corticosterone levels were induced in NIDDM rats compared to control (p < 0.05), but FB, TM or GX significantly brought the corticosterone back (p < 0.05) to the control levels. Considering steroidogenic organs, IDDM rats with or without TA treatments had heavier testis and adrenal glands, but not epididymis, than normal rats with or without TA treatments. There were no effects of TA on the weight of steroidogenic organs among normal and NIDDM rats. However, GX feeding in NIDDM rat had lesser testis weight compared to NIDDM rats. The expression of StAR protein and P450scc enzyme were not different among groups in IDDM and NIDDM rats. Plasma testosterone productions were suppressed in normal rats with the feeding of TA (FB and TM). IDDM rats did have lower testosterone, but not in NIDDM, and FB or TM could not restore the inhibitory effects. The induction of IDDM or NIDDM rats did affect steroidogenesis and steroidogenic organ weights, and the feeding of TA had different effects on steroidogenesis in different types of diabetic rats.