Inhibitory effects of cryptoporus polysaccharide on airway constriction, eosinophil release, and chemotaxis in guinea pigs.
OBJECTIVE
To study effects of cryptoporus polysaccharide (CP) on antigen-induced bronchoconstriction, eosinophil peroxidase (EPO) release in vivo, and on platelet activating factor (PAF)-induced eosinophil chemotaxis in vitro in guinea pig.


METHODS
The asthma model of guinea pig was formed with ovalbumin (OVA). The changes of lung resistance (R(L)) and dynamic lung compliance (C(dyn)), EPO level in bronchoalveolar lavage fluids (BALF) and eosinophil migration were determined.


RESULTS
Pretreatment of CP at doses of 3, 9, and 27 mg/kg by intragastric gavage (i.g.), qd for 10 d, inhibited early asthma response in a dose-dependent manner. Inhibitory rates of mean increase value from 1 to 30 min of R(L) were 34.8 %, 74.4 % (P<0.05), and 79.6 % (P<0.05), respectively. Inhibitory rate of mean reduction value of C(dyn) were 22.9 %, 40.5 % (P<0.01), and 66.5 % (P<0.01), respectively. Pretreatment of CP at doses of 3, 9, and 27 mg/kg also inhibited late asthma response, and the reduction of EPO level in BALF were 3.1 %, 16.9 % (P<0.01), and 20.1 % (P<0.01), respectively. The inhibitory rates of CP at concentrations of 0.13, 1.3, 13, 130 nmol/L to eosinophil migration induced by PAF were 6.8 %, 17.2 % (P<0.05), 29.6 % (P<0.01), and 35.9 % (P<0.01).


CONCLUSIONS
CP protects lung against increase of R(L) and reduction of C(dyn), decreases EPO level in the asthma model, and inhibits eosinophil chemotaxis induced by PAF. The results suggest that CP may be a novel antiinflammatory agent for the treatment of asthma and allergic diseases.
Zhao
Xiao-yan
XY
Zhejiang Respiratory Drugs Research Laboratory of State Drugs Administration of China, Medical School of Zhejiang University, Hangzhou 310031, China.
Xie
Qiang-min
QM
Chen
Ji-qiang
JQ
Ke
Chuan-kui
CK
D000403:Airway Resistance / Q000187:drug effects; D000818:Animals; D018927:Anti-Asthmatic Agents / Q000494:pharmacology; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology; D001249:Asthma / Q000139:chemically induced / Q000378:metabolism / Q000503:physiopathology; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry; D016084:Bronchoconstriction / Q000187:drug effects*; D002634:Chemotaxis, Leukocyte / Q000187:drug effects*; D047209:Eosinophil Peroxidase; D004804:Eosinophils / Q000502:physiology; D005260:Female; D006168:Guinea Pigs; D008170:Lung Compliance / Q000187:drug effects; D008297:Male; D010047:Ovalbumin; D010544:Peroxidases / Q000378:metabolism*; D011124:Polyporaceae / Q000737:chemistry; D011134:Polysaccharides / Q000302:isolation & purification / Q000494:pharmacology*
D018927:Anti-Asthmatic Agents; D000894:Anti-Inflammatory Agents, Non-Steroidal; D011134:Polysaccharides; D010047:Ovalbumin; D047209:Eosinophil Peroxidase; D010544:Peroxidases