Analysis of gene expression and functional changes of adrenal gland in a rat model of kidney yang deficiency syndrome treated with Sini decoction.

Sini decoction (SND), a well-known traditional Chinese medicine, has been used to treat kidney Yang deficiency for similar to 1,800 years. The present study aimed to evaluate the effects of SND treatment on hypothalamic-pituitary-adrenal axis hormones in a rat model of Yang deficiency and to explore the molecular mechanisms using microarray analysis of adrenal glands and in vitro adrenocortical cell culture systems. The results indicated that SND treatment recovered circulating serum cortisol, adrenocortical hormone (ACTH) and testosterone levels in a yang deficiency model. Immunohistochemical analysis of pituitary and hypothalamic tissues confirmed increased expression of ACTH and corticotropin-releasing factor, respectively, in response to SND treatment. Microarray analysis identified a marked upregulation of genes involved in metabolic and stress response pathways in rat adrenal tissues in response to SND treatment, exemplified by cyclooxygenase-2 and nuclear factor (NF)-B. In vitro, SND exerted a protective effect on mitochondria in response to H2O2 exposure also activated NF-B and cyclic adenosine monophosphate response element binding protein reporter gene activity. These results contributed towards an improved understanding of how SND effectively alleviates the symptoms of kidney Yang deficiency syndrome at the molecular level.