These data suggest that chronic stress-induced abnormal brain plasticity and reduction in neurogenesis can be prevented by a pretreatment with the Probio'Stick(®) formulation, suggesting that probiotics modulate neuroregulatory factors and various signaling pathways in the central nervous system involved in stress response.

The value of exogenously supplied live bacteria for the maintenance of health in humans has been recognized both scientifically in the published literature and commercially in the availability of probiotic products. Although many bacteria characterized as probiotics are strains of Lactobacillus or Bifidobacterium, sporeforming bacteria, primarily of the genus Bacillus and related genera, have also been studied and commercialized as probiotics. This article reviews the characterization, efficacy, and safety of sporeformers used as probiotics.

The aim of this study was to determine if probiotics reduce epithelial injury following exposure to Escherichia coli O157:H7 and E. coli O127:H6. The pretreatment of intestinal (T84) cells with lactic acid-producing bacteria reduced the pathogen-induced drop in transepithelial electrical resistance. These findings demonstrate that probiotics prevent epithelial injury induced by attaching-effacing bacteria.

Patients with recurrent C. difficile infection harbor large numbers of microbes with antibiotic resistance genes. Fecal microbial transplantation eradicates pathogenic organisms and eliminates antibiotic-resistance genes suggesting this may be a viable treatment option to eradicate multidrug resistant bacteria from patients.

Myocardial infarction (MI) in rats is accompanied by apoptosis in the limbic system and a behavioural syndrome similar to models of depression. We have already shown that probiotics can reduce post-MI apoptosis and designed the present study to determine if probiotics can also prevent post-MI depressive behaviour. We also tested the hypothesis that probiotics achieve their central effects through changes in the intestinal barrier. MI was induced in anaesthetised rats via 40-min transient occlusion of the left anterior coronary artery. Sham rats underwent the same surgical procedure without actual coronary occlusion. For 7 d before MI and between the seventh post-MI day and euthanasia, half the MI and sham rats were given one billion live bacterial cells of Lactobacillus helveticus R0052 and Bifidobacterium longum R0175 per d dissolved in water, while the remaining animals received only the vehicle (maltodextrin). Depressive behaviour was evaluated 2 weeks post-MI in social interaction, forced swimming and passive avoidance step-down tests. Intestinal permeability was evaluated by oral administration with fluorescein isothiocyanate -dextran, 4 h before euthanasia. MI rats displayed less social interaction and impaired performance in the forced swimming and passive avoidance step-down tests compared to the sham controls (P,0·05). Probiotics reversed the behavioural effects of MI (P, 0·05), but did not alter the behaviour of sham rats. Intestinal permeability was increased in MI rats and reversed by probiotics. In conclusion, L. helveticus R0052 and B. longum R0175 combination interferes with the development of post-MI depressive behaviour and restores intestinal barrier integrity in MI rats. Key words: Probiotics: Myocardial infarction: Depression: Intestinal barrierAfter myocardial infarction (MI), 65 % of patients present depressive symptoms (1) , and about 20 % of them incur major depression (1,2) . Evidence of a poor prognosis is particularly strong in patients with such symptoms (3 -6) : the risk of cardiac death within 6 months after acute MI is approximately four times greater in patients with depression compared to nondepressed control subjects (5) . The mechanism is still hypothetical, but it has been postulated that the inflammatory state observed after MI is responsible for post-MI depression (7) .Elevation of pro-inflammatory cytokine levels (8,9) has been documented after myocardial ischaemia, and their attenuation is correlated with depressive behaviour reduction (10) . Our previous study indicated that MI rats present symptoms that are similar to human depression. MI rats drink significantly less sucrose and remain more immobile in the forced swimming test, indicating a state of anhedonia and behavioural despair, respectively. These behavioural signs are blocked by the tricyclic anti-depressant, desipramine, the selective serotonin reuptake inhibitor, sertraline (11,12) , and the cytokine synthesis inhibitor pentoxifylline (13) . The present experimental model of post-MI depression manifest...