Improving the Efficiency and Safety of Aspirin by Complexation with the Natural Polysaccharide Arabinogalactan.

Background: The main undesirable side effect of the aspirin is the damage to the gastrointestinal mucosa, leading to the formation of erosions, peptic ulcers, and as a result, bleeding. To overcome this problem “host-guest” complexation with natural polysaccharide arabinogalactan could be applied. Methods: The complex with a weight ratio of ASA:AG = 1:10 was prepared by solid phase method in a rotary mill. Complex was administered orally to mice or rats at doses of 250, 500 or 1000 mg/kg. The “acetic acid induced writhing” and “hot plate” tests were used as an in vivo pain models. The antiinflammatory activity was studied using “histamine swelling” test. Also, long-term (30 days) oral introduction of the complex to rats was performed and gastric mucosa damages were evaluated. In all experiments pure aspirin (ASA) was used as a control in appropriate doses. Results: The minimal effective analgesic dose of the complex was 250 mg/kg, equivalent to 23 mg/kg of ASA, a dose in which aspirin itself was not active. The anti-inflammatory effect was found at relatively higher doses: 500 and 1000 mg/kg (46 and 92 mg/kg of ASA respectively) for the complex and only at 100 mg/kg for the ASA. Long-term introduction of the complex at doses of 250 and 500 mg/kg was safe for gastric mucosa, while ASA at the dose of 50 mg/kg showed a strong gastric mucosal damage. Conclusion: The effective analgesic and anti-inflammatory doses of 1:10 aspirin complex with arabinogalactan are twice less compared to pure aspirin and safer for the gastrointestinal mucosa.