In-vivo Immunomodulatory Potential of Standardized Pueraria Tuberosa Extract and Its Isoflavonoids

Objective: The present study was designed to investigate the immunomodulatory potential of Pueraria tuberosa tuber extract and isoflavones puerarin, daidzein and genistein in rats. Methods: The immunomodulatory potential of standardized P. tuberosa tuber extract (100-200 mg/kg; p.o.) and isoflavones puerarin (25-50 mg/kg; p.o.), daidzein (25-50 mg/kg; p.o.) and genistein (25-50 mg/kg; p.o.) was evaluated in swiss albino rats. Immunomodulatory potential was evaluated against sheep red blood cells (SRBCs) antigenic challenge using the models include total and differential leukocyte cell counts, nitrobluetetrazolium reduction test, haemagglutinin titre assay, neutrophil adhesion test, carbon clearance test and delayed type hypersensitivity reaction. The study was also constituted the active marker based RP-HPLC standardization of PTTE. Results: RP-HPLC analysis revealed those P. tuberosa tubers extract contains (w/w) puerarin (8.31% ± 0.06), daidzein (1.70% ± 0.04) and genistein (1.37% ± 0.02). Oral administration of the P. tuberosa extract, puerarin and daidzein dose dependently increased total leukocyte cell count, monocyte and lymphocyte counts, nitroblue-tetrazolium reduction, haemagglutinin titre and phagocytic index whereas suppressed delayed type hypersensitivity response in their specified concentration range in SRBC immunized rats. The P. tuberosa extract was also enhanced the neutrophil adhesion, while puerarin and daidzein had no effect on the neutrophil adhesion. Genistein dose dependently suppressed all the above parameters. Results suggest that the P. tuberosa extract augmented some innate as well as humoral immune responses against SRBC challenged in rats. Conclusion: P. tuberosa holds a promising therapeutic potential as an immunomodulator and the effects mostly due to the effects of isoflavones puerarin, daidzein and genistein.