Anemarrhenae Rhizoma: Material Basis and Mechanism of Its Renal-Yin-Deficiency Syndrome Treating Effect and Its Effect Enhancement after Salt Stir-frying

Abstract Background This study aims to find out renal-yin-deficiency syndrome (RYDS) treating component of Anemarrhenae Rhizoma (AR) and its RYDS-treating mechanism, the contents of neomangiferin and mangiferin in raw AR after salt stir-frying, and the cause of enhancement of RYDS-treating effect of salt stir-fried AR. Methods HPLC method was used for determining contents of mangiferin and neomangiferin in the various AR samples and simulative salt stir-fried neomangiferin. Western Blot, ELISA, RT-PCR and some conventional methods were used to investigate the RYDS-treating effect of raw AR, salt stir-fried AR and mangiferin. Results Content of neomangiferin decreased and that of mangiferin increased in water stir-fried AR and salt stir-fried AR; HPLC chromatogram showed a mangiferin peak in simulative salt stir-fried neomangiferin; both AR samples and mangiferin exerted RYDS-treating effect by reducing/increasing certain general and specific physiological indexes, reducing levels of T3, T4, FT3, FT4, cAMP, and the ratio of cAMP/cGMP; elevating levels of TSH and cGMP; and increasing mRNA and protein expressions of PI3K/AKT/mTOR pathway in kidney in RYDS rats. The RYDS-treating effect of salt stir-fried AR and mangiferin was stronger than that of raw AR. Conclusions Results of the study show that mangiferin in AR is the material basis of the RYDS-treating effect, the mechanism of the effect is rectifying and adjusting a series of physiological, endocrino-immunological and genetic abnormalities caused by RYDS, and enhancement of effect of salt stir-fried AR is because of the increase in the content of mangiferin.