Water-soluble polysaccharides of Ganoderma lucidum (W.Curt.:Fr.) P. Karst. (Aphyllophoromycetideae) alleviate the dose-limiting toxicities of irinotecan (CPT-11)

Ganoderma lucidum extracts attenuated cisplatin-induced nausea and vomiting in rats. The clinical use of irinotecan (CPT-11) is hindered by dose-limiting diarrhea and myelosuppression. This study aimed to investigate whether a combination of G. lucidum polysaccharides (25 mg/kg by gavage) modulated the toxicities of CPT-11 in rats. The rat toxicity model was constructed by treatment of CPT-11 at 60 mg/kg/day by intravenous injection. Incidence of acute and delayed-onset diarrhea, blood cell counts, and body weight were monitored throughout the study. Administration of CPT-11 and a control vehicle (sterile water) for four days to rats induced a significant decrease in neutrophils and lymphocytes counts, body weight loss, and severe acute and delayed-onset diarrhea. These toxicities were suppressed when CPT-11 was combined with G. lucidum polysaccharides. Further study is needed to explore the mechanisms for the protective effect of G. lucidum polysaccharides against CPT-11 toxicity.