Physicochemical properties of polysaccharides from Ligusticum chuanxiong and analysis of their anti-tumor potential through immunoregulation
Cheng Zhong, Zijing Liu, Xuyu Zhang, Youwei Pu, Zhongwei Yang, Yixi Bao
Abstract
We investigated the extraction, purification, physicochemical properties and biological activity of Ligusticum chuanxiong polysaccharides (LCXPs). Two polysaccharide fractions (Ligusticum chuanxiong [LCX]P-1a and LCXP-3a) were obtained by DEAE Sepharose™ Fast Flow and Sephacryl™S-300 high resolution column chromatography. The results showed that the molecular weight of LCXP-1a and LCXP-3a was 11.159 kDa and 203.486 kDa, respectively. LCXP-1a is composed of rhamnose, glucuronic acid, galacturonic acid, and glucose at a molar percentage of 0.52 : 1.88 : 1.06 : 95.36, But LCXP-3a has another molar percentage of mannose, rhamnose, glucuronic acid, galacturonic acid, glucose, galactose, xylose, arabinose, and fucose of 0.64 : 6.69 : 1.03 : 43.74 : 2.20 : 26.90 : 0.82 : 15.94 : 1.80. Both LCXP-1a and LCXP-3a could stimulate macrophages to produce NO, TNF-α, IL-6, and IL-12p70. Co-culturing macrophages and hepatocellular carcinoma cells showed that LCXP-1a and LCXP-3a inhibited the growth of HepG2 and Hep3B through immunoregulation. They arrested the cell cycle at the G0/G1 phase and promoted apoptosis. Moreover, there was no cytotoxicity to the hepatocyte cell line, LO2. We also noted that the immunomodulatory activity and anti-tumor activity of LCXP-3a were significantly better than those of LCXP-1a. Our data demonstrate that LCXP-3a is potentially a well-tolerated and effective immunomodulatory adjuvant cancer treatment.