Natural Products from Phyllostachys nigra var. henonis

Inhibition of interleukin-12 production in mouse macrophages via suppression of nuclear factor-kappaB binding activity by Phyllostachys nigra var. henonis.[Pubmed: 17464773]

Pharmacological inhibition of interleukin-12 (IL-12) production may be a therapeutic strategy for preventing development and progression of disease in experimental models of autoimmunity. The acetone fraction prepared from bamboo, Phyllostachys nigra var. henonis, potently inhibited the Lipo polysaccharide (LPS)-induced IL-12 production from RAW264.7 monocytic cell-line in a dose-dependent manner. The repressive effect mapped to a region in the IL-12 gene promoter containing a binding site for NF-kappaB. Furthermore, activation of macrophages by LPS resulted in markedly enhanced binding activity to the NF-kappaB site, which significantly decreased upon addition of the acetone fraction of Phyllostachys nigra var. henonis. This indicated that the acetone fraction inhibited IL-12 production in LPS-activated macrophages via inhibition of NF-kappaB binding activity.

Enhancement of 1,25-dihydroxyvitamin D3- and all-trans retinoic acid-induced differentiation of human leukemia HL-60 cells by Phyllostachys nigra var. henonis.[Pubmed: 17464772]

Human myeloid leukemia HL-60 cells are differentiated into monocytic or granulocytic lineage when treated with 1,25-dihydroxyvitamin D(3) [1,25-(OH)(2)D(3)] or all-trans retinoic acid (RA), respectively. In this study, the effect of acetone fraction prepared from bamboo leaf on cell differentiation was investigated in a HL-60 cell culture system. Treatment of HL-60 cells with 50-400 microg/ml acetone fraction of bamboo leaf for 72 hr inhibited cell proliferation and induced a little increase in cell differentiation, as demonstrated by the MTT and nitroblue tetrazolium reduction assay. Interestingly, synergistic induction of HL-60 cell differentiation was observed when the acetone fraction of bamboo leaf was combined with either 5 nM 1,25-(OH)(2)D(3) or 50 nM all-trans RA. Flow cytometric analysis indicated that combinations of 1,25-(OH)(2)D(3) and the acetone fraction of bamboo leaf stimulated differentiation predominantly to monocytes, whereas combinations of all-trans RA and the acetone fraction of bamboo leaf stimulated differentiation predominantly to granulocytes. These results suggest that the acetone fraction of bamboo leaf enhanced leukemia cell differentiation and suggest a possibility of bamboo in the treatment of leukemia.