RESUMO

Agaricus brasiliensis is a medicinal mushroom widely eaten and prescribed in the world. We have recently examined the structure and antitumor activity of polysaccharide fractions of the fruit body and concluded a significant contribution of the highly branched 1,3-beta-glucan moieties to the activity. In the present study, the pharmacological effect of the cold and the hot water extracts (CWE and HWE) on a murine diabetic model C57BL Ksj-db/db was examined from the viewpoints of physiology, immunology, and histology. CWE and HWE were orally administered to db/db mice every day for 28 weeks. Compared to the water administered control group, the body weight, urinary glucose exclusion, urinary pH, blood glucose level, and organs weight were comparable. The number of cells in CWE administered mice was significantly reduced compared to the control and the HWE administered group, and the ratios of T cells versus B cells (CD3/B220) and T cells versus NK cells (CD3/NK1.1) were relatively increased in the CWE administered group. The splenocytes of CWE administered mice produced a higher concentration of IL-6 by Con A stimulation and IFN-_γ and IL-6 by LPS stimulation. By megascopic and microscopic examinations of renal sections, the number of the mice having abnormal kidney was 3/5 (control), 2/5 (HWE), and 0/5 (CWE), and suggested the activity of the renal protection in CWE. These facts strongly suggested that the pharmacological action of the cold water extract of A. brasiliensis significantly differ from that of the hot water extract.