Effect of Lactobacillus paracasei subsp. paracasei NTU 101 powder to improve memory and learning ability on stroke rats induced by bilateral common carotid artery occlusion-reperfusion

Cerebral stroke reperfusion caused brain injury including a large number of free radicals generated in the brain caused by oxidative stress damage, energy imbalance, inflammation and apoptosis. Many papers previously mentioned that lactic acid bacteria (LAB) can reduce oxidative stress, inflammation and other effects. On the other hand, in recent years, probiotics affecting cognitive function of the brain through the brain-gut axis indirectly have been reported. This study investigated whether the Lactobacillus paracasei subsp. paracasei NTU 101 improves learning and memory and reduces brain inflammation in stroke rat. In this research, all male Sprague-Dawley rats accept bilateral common carotid artery occlusion-reperfusion (BCCAO) operation to induce memory and learning ability impairment of stroke. This animal model leaded to learning and memory impairment and a serious inflammation of the brain, while NTU 101 administration improved cognitive impairment. Additionally, NTU 101 inhibited astrocytes and microglia activation, therefore reduced proinflammatory cytokines including tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-1β and nitric oxide (NO). Moreover, the expression of inflammatory-related proteins inducible nitric oxide synthase (iNOS), NF-κB and protein of MAPKs signaling pathway were decreased in NTU 101-treated groups. In summary, administration of NTU 101 can against the impairment of memory and learning ability induced by stroke via ameliorating inflammation.