Brain ischemia and reperfusion (I/R) injury may lead to a poor prognosis for ischemic stroke, which could be alleviated by antioxidants with diminished oxidative stress. Betaine is a natural nutrient found in beetroot and seafood to improve cognitive performance in the elderly. The present study investigated whether betaine could protect the brain from I/R injury. Results showed that betaine treatment could reduce H2O2-induced cell death in the PC12 cell line. Pretreatment with betaine reduced the brain infarct volume and neuronal apoptosis in a rat I/R injury model induced by 2-h middle cerebral artery occlusion (MCAO). Biochemical analyses indicated that betaine treatment decreased proinflammatory cytokine production and reduced oxidative stress after I/R injury. Betaine increased the expression of antioxidative enzymes, such as glutathione peroxidase 4 (Gpx4) and superoxide dismutase 1 (Sod1), and antioxidative nonenzymatic genes, such as 3-mercaptopyruvate sulfurtransferase (Mpst), methionine sulfoxide reductases b1 (Msrb1), and Msrb2. These data suggest that betaine exerts a neuroprotective effect in I/R injury through enzymatic and nonenzymatic antioxidative systems and anti-inflammatory mechanisms.NEW & NOTEWORTHY These data suggested that betaine exerted a neuroprotective effect in I/R injury through enzymatic and nonenzymatic antioxidative systems.
Keywords: betaine; inflammation; ischemia and reperfusion injury; oxidative stress.