Effects of dietary 5-methoxyindole-2-carboxylic acid on brain functional recovery after ischemic stroke

Stroke leads to devastating outcomes including impairments of sensorimotor and cognitive function that may be long lasting. New intervention strategies are needed to overcome the long-lasting effects of ischemic injury. Previous studies determined that treatment with 5-methoxyindole-2-carboxylic acid (MICA) conferred chemical preconditioning and neuroprotection against stroke. The purpose of the current study was to determine whether the preconditioning can lead to functional improvements after stroke (done by transient middle cerebral artery occlusion). After 4 weeks of MICA feeding, half the rats underwent ischemic injury, while the other half remained intact. After one week recovery, all the rats were tested for motor and cognitive function (rotorod and water maze). At the time of euthanasia, measurements of long-term potentiation (LTP) were performed. While stroke injury led to motor and cognitive dysfunction, MICA supplementation did not reverse these impairments. However, MICA supplementation did improve stroke-related impairments in hippocampal LTP. The dichotomy of the outcomes suggest that more studies are needed to determine optimum duration and dosage for MICA to lead to substantial motor and cognitive improvements, along with LTP change and neuroprotection.