Lactobacillus casei CRL 431 improves endothelial and platelet functionality in a pneumococcal infection model

Area of Science:

• Microbiology
• Immunology
• Hematology

Background:

• Streptococcus pneumoniae infection triggers coagulation and platelet aggregation, contributing to disease severity.
• Unbalanced hemostatic system and endothelial cell activation are key in pneumococcal pneumonia pathogenesis.
• Exaggerated hemostatic activity can significantly worsen disease outcomes.

Purpose of the Study:

• To investigate the effects of Lactobacillus casei CRL 431 on platelet and endothelial activation in a mouse model of respiratory pneumococcal infection.
• To assess Lactobacillus casei's potential role in modulating the hemostatic system during S. pneumoniae infection.

Main Methods:

• Oral administration of Lactobacillus casei CRL 431 to mice infected with Streptococcus pneumoniae.
• Evaluation of platelet counts, P-selectin expression, von Willebrand factor (vWF), and vascular cell adhesion molecule 1 (VCAM-1) levels.
• Analysis of CXCR-4 leukocytes, annexin V expression, cell death, and antithrombin levels in lung tissue and bronchoalveolar lavage.

Main Results:

• S. pneumoniae infection increased platelet counts, P-selectin, vWF, and VCAM-1, while decreasing antithrombin and CXCR-4 leukocytes, leading to increased cell death.
• Lactobacillus casei administration restored platelet counts, modulated P-selectin expression, and reduced vWF and VCAM-1 levels.
• L. casei treatment led to higher annexin V expression, reduced lung cell death, and normalized antithrombin levels, indicating reduced coagulation activation.

Conclusions:

• Lactobacillus casei CRL 431 favorably modulates platelet and endothelial function during Streptococcus pneumoniae pulmonary infection.
• This probiotic strain shows promise in preventing thrombotic complications associated with pneumococcal pneumonia, particularly in high-risk individuals.
• L. casei offers potential as a novel therapeutic or preventive agent for thrombosis linked to various diseases.