Immunology of pre- and probiotic supplementation

Heat Sepsis Precedes Heat Toxicity in the Pathophysiology of Heat Stroke-A New Paradigm on an Ancient Disease

Heat stroke (HS) is an ancient illness dating back more than 2000 years and continues to be a health threat and to cause fatality during physical exertion, especially in military personnel, fire-fighters, athletes, and outdoor laborers. The current paradigm in the pathophysiology and prevention of HS focuses predominantly on heat as the primary trigger and driver of HS, which has not changed significantly for centuries. However, pathological and clinical reports from HS victims and research evidence from animal and human studies support the notion that heat alone does not fully explain the pathophysiology of HS and that HS may also be triggered and driven by heat- and exercise-induced endotoxemia. Exposure to heat and exercise stresses independently promote the translocation of lipopolysaccharides (LPS) from gram-negative bacteria in the gut to blood in the circulatory system. Blood concentration of LPS can increase to a threshold that triggers the systemic inflammatory response, leading to the downstream ramifications of cellular and organ damage with sepsis as the end point i.e., heat sepsis. The dual pathway model (DPM) of HS proposed that HS is triggered by two independent pathways sequentially along the core temperature continuum of >40 °C. HS is triggered by heat sepsis at Tc < 42 °C and by the heat toxicity at Tc > 42 °C, where the direct effects of heat alone can cause cellular and organ damage. Therefore, heat sepsis precedes heat toxicity in the pathophysiology of HS.

Genetically Engineered Bacteria for Treating Human Disease

Bacteria have now been harnessed to combat human diseases, especially to meet the challenge of antimicrobial resistance. Modulating the microbiome, particularly by genetically engineering the bacteria, has provided proof-of-concept as potential pharmacotherapy, but those involved in this field should engage in discussion as how to move forward.

The Effects of Synbiotic "Bifidobacterium lactis B94 plus Inulin" Addition on Standard Triple Therapy of Helicobacter pylori Eradication in Children

AIM

The aim of this study is to evaluate the effects of the synbiotic Bifidobacterium lactis B94 plus inulin addition to the standard triple therapy on Helicobacter pylori (H. pylori) infection eradication rates.

METHODS

Children aged 6-16 years who had biopsy proven H. pylori infection were randomly classified into two groups. The first group received the standard triple therapy consisting of amoxicillin + clarithromycin + omeprazole. The second group was treated with the standard triple therapy and Bifidobacterium lactis B94 (5 × 10⁹ CFU/dose) plus inulin (900 mg) for 14 days, concurrently. Eradication was determined by ¹⁴C-urea breath test 4-6 weeks after therapy discontinuation.

RESULTS

From a total of 69 H. pylori infected children (F/M = 36/33; mean ± SD = 11.2 ± 3.0 years), eradication was achieved in 20/34 participants in the standard therapy group and 27/35 participants in the synbiotic group. The eradication rates were not significantly different between the standard therapy and the synbiotic groups [intent-to-treat, 58.8% and 77.1%, resp., p = 0.16; per-protocol, 64.5% and 81.8%, resp., p = 0.19]. There was no difference between the groups in terms of symptom relief (p = 0.193). The reported side effects were ignorable.

CONCLUSION

Considering the eradication rates, synbiotic addition to therapy showed no superiority over the standard triple therapy conducted alone. This trial is registered with NCT03165253.

Biological effects of propionic acid in humans; metabolism, potential applications and underlying mechanisms

Undigested food is fermented in the colon by the microbiota and gives rise to various microbial metabolites. Short-chain fatty acids (SCFA), including acetic, propionic and butyric acid, are the principal metabolites produced. However, most of the literature focuses on butyrate and to a lesser extent on acetate; consequently, potential effects of propionic acid (PA) on physiology and pathology have long been underestimated. It has been demonstrated that PA lowers fatty acids content in liver and plasma, reduces food intake, exerts immunosuppressive actions and probably improves tissue insulin sensitivity. Thus increased production of PA by the microbiota might be considered beneficial in the context of prevention of obesity and diabetes type 2. The molecular mechanisms by which PA may exert this plethora of physiological effects are slowly being elucidated and include intestinal cyclooxygenase enzyme, the G-protein coupled receptors 41 and 43 and activation of the peroxisome proliferator-activated receptor γ, in turn inhibiting the sentinel transcription factor NF-κB and thus increasing the threshold for inflammatory responses in general. Taken together, PA emerges as a major mediator in the link between nutrition, gut microbiota and physiology.