Chungkookjang, a soy food, fermented with Bacillus amyloliquefaciens protects gerbils against ishcmeic stroke injury, and post-stroke hyperglycemia

[Display omitted] •Chungkookjang, soybeans fermented with Bacillus amyloliquefaciens, had thrombolytic activity.•Chungkookjang protected against neuronal cell death in gerbils with transient occlusion of the arteries.•Chungkookjang alleviated short-term memory loss and neurological symptoms in stroke induced gerbils.•Chungkookjang reduced proinflammatory cytokines and improved blood flow.•Chungkookjang increased Bacteriodia and decreased Clostridia to similar profiles as the normal-control in the gut. Chungkookjang is a traditional Korean fermented soybean food with anti-diabetic and thrombolytic activity. It may also have anti-stroke activity. We determined that chungkookjang made with Sunchang Research Center for Fermentation Microbes 100730 and 100731 strains of Bacillus amyloliquefaciens(SRCM100730; CKJ730) and SRCM100731(CKJ731) protected against ischemic stroke and post-stroke hyperglycemia in Mongolian gerbils with ischemic stroke induced by transient occlusion of the carotid arteries. Gerbil fed 4.5% cooked soybeans (CSB), CKJ730, CKJ731, or cellulose (negative-control) in 40 energy% fat diets for 3 weeks, and then had artery occlusion for 8 min and continued taking the assigned diet for 5 weeks. CKJ730 and CKJ731 had thrombolytic activity and prevented neuronal cell death. Consequently, they improved short-term memory and spontaneous alteration compared to the negative-control. CKJ730 and CKJ731 improved neurological symptoms including drooped eyes, crouched posture, flexor reflex, and walking patterns the most among the stroke-induced gerbils. CKJ730 and CKJ731 increased active time, grip strength, and blood flow measured by Doppler compared to the negative-control. CKJ730 protected against post-stroke glucose dysregulation by restoring β-cell mass in the gerbils with transient artery occlusion. Serum tumor necrosis factor-α and interleukin-1β levels were lower in CKJ730 and CKJ731 than the negative-control. CSB also improved glucose metabolism and suppressed inflammatory cytokines, but less than CKJ730 and CKJ731. Clostridia increased, and Bacteriodia slightly decreased in the negative-control group, compared to the normal-control. CKJ730 and CKJ731 changed the amounts of Bacteriodia and Clostridia to be similar to normal-control. In conclusion, the daily intake of chungkookjang fermented with B. amyloliquefaciens improved the gut microbiome, increased blood flow to the brain, suppressed systemic inflammation, and may reduce the susceptibility t