The effects of hyperbaric oxygen on serum matrix metalloproteinase-9, intercellular adhesion molecule-1 and brain edema in patients with intracerebral hemorrhage

Objective To investigate the effects of hyperbaric oxygen （HBO） therapy on serum matrix metalloproteinase-9 （MMP-9） and intercellular adhesion molecule-1 （ICAM-1） levels, and on brain edema in patients with intracerebral hemorrhage. Methods Seventy-six subjects with intracerebral hemorrhage were divided into a routine treatment group （40 cases） and a.HBO treatment group （36 cases）. 30 healthy persons served as a control group. Serum MMP-9 and ICAM-1 levels were measured before and after treatment. MRI images of the subjects＇ brains were prepared at the 5 -7 th and 25th days. Absolute edema volumes and relative edema volumes were measured on T2-weighted images. Results （1）The serum MMP-9 and ICAM-1 levels in the routine therapy and HBO groups were higher than those in the control group at the outset （P ≤0. 01 ）. Both indices peaked on the 5th day, but there was no significant difference between the two treated groups. At the 15th and 25th day （ after 10 and 20 HBO treatments） , the serum MMP-9 and ICAM-1 levels in the HBO group had decreased remarkably and were significantly lower than those in the routine therapy group （P ≤〈 0.01 ）. （2）At the 5 - 7th and 25th days, both absolute edema volumes and relative edema volumes in the HBO group were significantly smaller than those in the routine therapy group （P≤〈 0.05, P ≤ 0.01 ）. （3）Serum M MP-9 and ICAM-1 levels were positively correlated with the brain edema volumes, and negatively correlated with decreased NIHSS scores （between pre- and post-treatment）. Conclusions HBO therapy may reduce serum MMP-9 and ICAM-1 levels in patients with intracerebral hemorrhage, and lessen the severity and range of brain edema. HBO is helpful for restoring nerve function. Early and repeated multiple HBO treatments are beneficial for patients. Key words: Hyperbaric oxygen ;  Intracerebral hemorrhage ;  Brain edema ;  Magnetic resonance ;  Matrix metalloproteinase-9 ;  Intercellular adhesion molecule-1