Vitamin E protects mice against Diplococcus pneumoniae type I infection

Area of Science:

• Immunology
• Nutritional Science

Background:

• * Diplococcus pneumoniae (DpI) poses a significant threat, necessitating effective immune interventions.
• * Vitamin E is known for its antioxidant properties, but its role in modulating specific immune responses requires further elucidation.

Purpose of the Study:

• * To investigate the protective effects of dietary Vitamin E against fatal Diplococcus pneumoniae type I infection in mice.
• * To determine the impact of Vitamin E on immune parameters such as survival rates and phagocytic activity.

Main Methods:

• * Mice were either non-immunized or immunized with DpI polysaccharide.
• * Dietary supplementation with dl-alpha-tocopheryl acetate (Vitamin E) was administered.
• * Survival rates were assessed post-challenge with DpI organisms.
• * Phagocytic activity was measured using the phagocytic index and carbon clearance tests.

Main Results:

• * Vitamin E supplementation (180 mg/kg diet) increased survival in non-immunized mice from 20% to 80% and in immunized mice from 15% to 70%.
• * A significant fourfold increase in the phagocytic index was observed in immunized mice receiving Vitamin E.
• * Carbon clearance rates were elevated, indicating enhanced general phagocytic activity.
• * A biphasic dose response was noted for both survival and phagocytic index, suggesting a direct correlation.

Conclusions:

• * Dietary Vitamin E enhances protection against Diplococcus pneumoniae infection in mice.
• * Increased macrophage activity, potentially supported by enhanced antibody production, is the primary mechanism behind Vitamin E's protective effect.
• * Vitamin E demonstrates a dose-dependent relationship with improved phagocytosis and survival outcomes.