Intergenerational effects of pre-pregnancy chronic lipopolysaccharide from Porphyromonas gingivalis on the learning, memory and seizure susceptibility of offspring.

Abstract Objective The aim of this study was to investigate the effects of pre-pregnancy chronic exposure to Porphyromonas gingivalis LPS (Pg LPS) on the learning, memory, and seizure susceptibility of the offspring. Design To achieve periodontitis, Pg LPS (5 µg/kg) was injected into the gingival of five female rats every 48 hours for three weeks. Five control female rats received saline (0.9%) and five female were kept intact. The concentrations of TNF-α and IL-6 were measured in the blood samples. One week after the final injection, females were mated with intact males. Following birth and weaning, two male and two female offspring were randomly selected from each mother, and new groups of male and female offspring were defined for behavioral assessments. Morris water maze was used to evaluate spatial memory, shuttle box was used to investigate avoidance memory and a pentylenetetrazole-induced seizure was used to evaluate seizure susceptibility in the offspring. Results Spatial learning and avoidance memory significantly decreased in both male and female offspring of Pg LPS-exposed female rats, compared to the control offspring. Latency to reach seizure stages 1 and 2 significantly increased in the male offspring, but not the female offspring of Pg LPS-exposed female, compared to the control offspring. However, no significant difference was found in latency to reach stages 3-5. Conclusion Pre-pregnancy exposure to Pg LPS could affect some behavioral functions in both male and female offspring intergenerationally.