AQP4 and brain ischemia: Zhou et al. found that XXMD attenuated the loss of tight junction related protein zona occludens-1 (ZO-1), maintained the structural integrity of the tight junction complex, inhibited the excessive release and expression of aquaporin 4 (AQP4) mRNA, and ameliorated cerebral ischemia and edema in rats with focal cerebral ischemic stroke (Zhou et al., 2014).