Different flavonoids present in the micronized purified flavonoid fraction (Daflon 500 mg) contribute to its anti-hyperpermeability effect in the hamster cheek pouch microcirculation.

This study evaluated microcirculatory effects of the flavonoid substances that constitute the micronized purified flavonoid fraction (MPFF) (Daflon 500 mg) in comparison to diosmin.In groups of 3 male hamsters, oral treatment with MPFF or diosmin (15 min before anesthesia) did not alter blood pressure. At 10 or 30 mg/kg, both MPFF and diosmin significantly decreased the leaky sites caused by ischemia/reperfusion (I/R) (30 min) in the hamster cheek pouch; the effect was significantly higher with MPFF (39+/-1% and 52+/-1%, respectively) than diosmin (18+/-1% and 37+/-3%, respectively). Eight groups of 3 hamsters each were treated with the components of MPFF. Diosmetin only decreased the number leaky sites at 30 mg/kg (decrease: 15+/-2%). The decrement at 10 and 30 mg/kg averaged at: 17+/-3% and 44+/-1%, respectively, for hesperidin; 19+/-1% and 46+/-2%, respectively, for linarin; and 30+/-1% and 44+/-1%, respectively, for isorhoifolin. Hesperidin, linarin, and isorhoifolin each displayed an anti-leakage effect comparable to or greater than diosmin. MPFF decreases permeability more than any of its single constituents, suggesting that the flavonoids present in its formulation have a synergistic action.These results illustrate that MPFF is more potent than single diosmin in this model of hyperpermeability and that each of the flavonoid substances present in MPFF contribute to its action.