Lactobacillus helveticus and Bifidobacterium longum taken in combination reduce the apoptosis propensity in the limbic system after myocardial infarction in a rat model

Myocardial infarction (MI) simulates the release of pro-inflammatory substances that induce apoptosis in the limbic system Pro-inflammatory cytokines are considered as the root cause of apoptosis, although the mechanism is not fully explained and/or understood at this time. In addition, depression may induce gastrointestinal perturbations that maintain the elevated levels of pro-inflammatory cytokines. It has been shown that some specific probiotic formulations may reduce gastrointestinal problems induced by stress and the pro/anti-inflammatory cytokine ratio Therefore, we hypothesised that probiotics, when given prophylactically, may diminish the apoptosis propensity in the limbic system following a MI. Male adult Sprague-Dawley rats were given probiotics (Lactobacillus helvencits and Bifidobacterium longum in combination) or placebo in their drinking-water for four consecutive weeks A MI was then induced in the rats by occluding the left anterior coronary artery for 40min. Rats were killed following a 72h reperfusion period Infarct size was not different in the two groups. Bax/Bcl-2 (pro-apoptotic/anti-apoptotic) ratio and caspase-3 (pro-apoptotic) activity were reduced in the amygdala (lateral and medial), as well as in the dentate gyrus in the probiotics group when compared with the placebo. Akt activity (anti-apoptotic) was increased in these same three regions. No significant difference was observed in Ca1 and Ca3 for the different markers measured In conclusion, the probiotics L helvetcus and B longum, given in combination a,, preventive therapy, reduced the predisposition of apoptosis found in different cerebral regions following a MI.