A Type II Arabinogalactan from Anoectochilus formosanus for G-CSF Production in Macrophages and Leukopenia Improvement in CT26-Bearing Mice Treated with 5-Fluorouracil

Abstract EN

Anoectochilus formosanus is an herb well known in Asian countries.

The polysaccharide isolated from A.

formosanus consists of type II arabinogalactan (AGAF), with branched 3,6-Gal as the major moiety.

In this study, AGAF was examined for the granulocyte colony-stimulating factor (G-CSF) production and related protein expression in RAW 264.7 murine macrophages.

The signaling pathway of G-CSF production involves AGAF and mitogen-activated protein kinases (MAPKs) inhibitors and pattern-recognition receptor antibodies.

AGAF was evaluated to ease the leukopenia in CT26-colon-cancer-bearing mice treated with 5-fluorouracil (5-FU).

The results of this study showed that AGAF was a stimulant for Toll-like receptor 2 and Dectin-1 and that it induced G-CSF production, through p38 and ERK MAPK, and NF-κB pathways.

In vivo examination showed that the oral administration of AGAF mitigated the side effects of leukopenia caused by 5-FU in colon-cancer-bearing mice.

In conclusion, the botanic type II AGAF in this study was a potent G-CSF inducer in vivo and in vitro.