Fucoidan from Fucus vesiculosus Fails to Improve Outcomes Following Intracerebral Hemorrhage in Mice

Intracerebral hemorrhage (ICH) is the most fatal stroke subtype, with no effective therapies. Hematoma expansion and inflammation play major roles in the pathophysiology of ICH, contributing to primary and secondary brain injury, respectively. Fucoidan, a polysaccharide from the brown seaweed Fucus vesiculosus, has been reported to activate a platelet receptor that may function in limiting bleeding, and to exhibit anti-inflammatory effects. As such, the aim of the present study was to examine the effects of fucoidan on hemorrhaging and neurological outcomes after ICH. Male CD-1 mice were subjected to experimental ICH by infusion of bacterial collagenase. Animals were randomly divided into the following groups: sham, ICH + vehicle, ICH + 25 mg/kg fucoidan, ICH + 75 mg/kg fucoidan, and ICH + 100 mg/kg fucoidan. Brain water content, neurobehavioral outcomes, and hemoglobin content were evaluated at 24 h post ICH. Our findings show that fucoidan failed to attenuate the ICH-induced increase in BWC. The neurological deficits that result from ICH also did not differ in the treatment groups at all three doses. Finally, we found that fucoidan had no effect on the hemoglobin content after ICH. We postulate that fucoidan treatment did not improve the measured outcomes after ICH because we used crude fucoidan, which has a high molecular weight, in our study. High-molecular-weight fucoidans are reported to have less therapeutic potential than low molecular weight fucoidans. They have been shown to exhibit anti-coagulant and pro-apoptotic properties, which seem to outweigh their anti-inflammatory and potential procoagulant abilities. We propose that using a low-molecular-weight fucoidan, or fractionating the crude polysaccharide, may be effective in treating ICH. Future studies are needed to confirm this.