Polysaccharide isolated from Parmelia tinctorum ameliorates ionizing irradiation-induced damage in mice.
In this study, WPT-A, a type of water-soluble homogeneous lichen polysaccharide, was isolated and purified from Parmelia tinctorum. We investigated whether WPT-A has radioprotective effects when administered before total-body irradiation (TBI). Mice were treated with WPT-A via intraperitoneal injection (i.p.) once per day for three consecutive days prior to 7, 7.5, 8.5, 10 or 10.5-Gy TBI. Our results indicated that the survival rate was enhanced at a range of levels of TBI. The calculated dose reduction factor (DRF) was 1.2. White blood cell (WBC) counts, spleen colony forming units (CFU-S) and bone marrow nucleated cell (BMNC) counts were used to investigate the radioprotective effects of WPT-A on the hematopoietic system. The treatment groups received WPT-A at 20, 50 and 80 mg/kg b.w. doses before 6.5-Gy TBI and showed significantly higher BMNC and WBC counts compared with the radiation-only group. The groups administered 50 and 80 mg/kg b.w. WPT-A showed a significant increase in CFU-S compared with the radiation-only group. We also carried out a single cell gel electrophoresis assay to explore the radioprotective effects of WPT-A on DNA damage. The results from single-cell gel electrophoresis of peripheral blood leukocytes showed that WPT-A attenuated radiation-induced DNA damage. These results indicate a potential use for WPT-A as a radioprotector.
Tianjin Key Laboratory of Molecular Nuclear Medicine, Institute of Radiation Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin, 300192, China xuwenqing@irm-cams.ac.cn.
Wenqing
W
Xu
Tianjin Key Laboratory of Molecular Nuclear Medicine, Institute of Radiation Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin, 300192, China.
Fujun
F
Yang
Tianjin Key Laboratory of Molecular Nuclear Medicine, Institute of Radiation Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin, 300192, China.
Xiu
X
Shen
Tianjin Key Laboratory of Molecular Nuclear Medicine, Institute of Radiation Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin, 300192, China.
Saijun
S
Fan
Tianjin Key Laboratory of Molecular Nuclear Medicine, Institute of Radiation Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin, 300192, China.
Qiang
Q
Liu
Tianjin Key Laboratory of Molecular Nuclear Medicine, Institute of Radiation Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin, 300192, China.
Dezhi
D
Wang
D000818:Animals; D003114:Colony-Forming Units Assay; D004249:DNA Damage; D006413:Hematopoietic System / Q000187:drug effects / Q000528:radiation effects; D008011:Lichens / Q000737:chemistry*; D051379:Mice; D008813:Mice, Inbred ICR; D010946:Plants, Medicinal / Q000737:chemistry; D011134:Polysaccharides / Q000302:isolation & purification / Q000494:pharmacology*; D011837:Radiation-Protective Agents / Q000302:isolation & purification / Q000494:pharmacology*; D014916:Whole-Body Irradiation
D011134:Polysaccharides; D011837:Radiation-Protective Agents
Parmelia tinctorum; comet assay; hematopoietic system; radioprotection; single cell gel electrophoresis