EFFECTS OF A PORPHYROMONAS-GINGIVALIS INFECTION ON INFLAMMATORY MEDIATOR RESPONSE AND PREGNANCY OUTCOME IN HAMSTERS

This study examines the effects of various localized, nondissemination challenges of Porphyromonas gingivalis on inflammatory mediator produ ction and pregnancy outcome in the golden hamster. Live or heat-killed (HK) organisms were inoculated into a previously implanted subcutaneo us tissue chamber on the 8th day of gestation to determine the effects on fetal weight, viability, and resorption. In one group of animals, HK organisms were inoculated prior to mating to determine the effects of previous exposure on day-8 gestational challenges. Chamber contents were assayed at 1 and 5 days after challenge for prostaglandin E(2) ( PGE(2)) and tumor necrosis factor alpha (TNF-alpha). All P. gingivalis challenges caused a significant increase in chamber PGE(2) and TNP-al pha at P < 0.01 in the following order of potency: HK < Live < HK+Live . For example, following the HK+Live challenge, PGE(2) levels increase d from 4.7 pg/ml at baseline to 362 pg/ml at day 5 and TNF-alpha incre ased from 26.4 pg/ml to 724 pg/ml at day 5. The same order of potency of the various challenges was maintained with regard to the toxic effe cts of P. gingivalis on pregnancy outcome. For the HK+Live challenge, fetal weight was decreased 24%; embryolethality increased to 26.5% and the percent fetal resorption increased to 10.6% compared with control animal levels. There was a statistically significant association betw een increasing levels of both PGE(2) and TNF-alpha. and fetal growth r etardation and embryolethality at P < 0.001. These data suggest that i nfections with gram-negative periodontal pathogens can elicit adverse pregnancy outcomes and that the levels of PGE(2) and TNF-alpha produce d as a result of challenge are associated with the severity of fetal e ffect.