The Effect of Licorice on Serum Lipid Peroxidation and Telomere Length of Immune Cells in Japanese Quail (as an Animal Model) Following Vaccination by Salmonella Bacterin

Bacterin-based vaccination may be a stressful condition, leading to harmful effects, such as high lipid peroxidation and telomere shortening. This study aimed to reduce these probable side effects via the administration of different concentrations of licorice (because of its anti-oxidative and anti-aging properties).

Japanese quails as animal models were reared for 42 days under standard conditions. The birds were divided into eight groups, including a control group, licorice treatments (licorice 0.02%, Licorice 0.04%, and licorice 0.08% groups), and Salmonella bacterin treatments (bacterin, bacterin+licorice 0.02%, bacterin+licorice 0.04%, and bacterin+licorice 0.08% groups). The Salmonella enterica bacterin-based vaccine was injected twice on days 14 and 28. Serum lipid peroxidation and telomere length of immune cells in all experimental groups were measured. 

Lipid peroxidation and telomere shortening enhanced following bacterin vaccination. Licorice at doses of 0.04%, 0.08%, or both reduced the lipid peroxidation and telomere shortening in non-vaccinated and vaccinated birds, while the dose of 0.02% was not effective.

This study confirmed the side effects of high lipid peroxidation and telomere attrition for S. enterica bacterin-based vaccination. Also, the improving properties of licorice for these side effects were considered to be effective.