[Phosphatidylcholine induces an increase in the production of interleukin-6 and improves survival of rats with neonatal sepsis caused by Klebsiella pneumoniae]. / La fosfatidilcolina induce un aumento en la producción de interleucina-6 y mejora la sobrevida de ratas con sepsis neonatal por Klebsiella pneumoniae.

Infections by gram-negative bacteria are one of the major causes of death in newborns. Bacterial clearance is deficient in septic neonates, which seems to increase their susceptibility to infections. In this study, we observed a significant improvement in clearance of Klebsiella pneumoniae in newborn wistar rats inoculated by intraperitoneal via with 800 mg k soybean phosphatidylcholine (PC), compared to the control group injected with PBS (p 0.05). The overall survival rate was improved (p 0.05) and the white blood cell counts showed a greater leukocytosis and neutrophilia during the peak of bacteremia in the PC treated animals. Circulating levels of interleukin-6 were greater in the PC group, which developed an intense splenic hematopoiesis of the granulocyte (p 0.05) and megakariocyte series (p 0.01). No significant changes were observed in bone marrow granulocyte deposits in both study groups. The improvement in survival rate, the changes in leukocyte counts and the splenic hematopoiesis may be associated with the increased production of IL-6. These results suggest that IL-6 plays a role in the protection mechanism induced by PC in this experimental model of newborn septicemia. PC seems to be an immunomodulator of the acute response to gram-negative bacterial infection.

Neonatal interleukin-1 beta, interleukin-6, and tumor necrosis factor: cord blood levels and cellular production.

In a prospective study, levels of interleukin-1 beta (IL-1 beta), interleukin-6) (IL-6), and tumor necrosis factor (TNF) were measured in a blind fashion in cord blood plasma from 92 neonates by specific immunoassays, and were correlated with the clinical courses of the infants, including type of delivery and perinatal complications. Plasma IL-1 beta concentration was undetectable in infants born by normal vaginal delivery or elective cesarean section but was significantly increased in infants born after induced vaginal deliveries (142 +/- 68 pg/ml) or urgent cesarean section (290 +/- 21 pg/ml; both p less than 0.05 compared with normal deliveries). The IL-1 beta levels were elevated in infants with severe perinatal complications (282 +/- 116 pg/ml; p less than 0.001), whereas TNF and IL-6 levels were not related to these complications. Infants with isolated perinatal infectious complications had elevated levels of plasma IL-6 compared with those of sick neonates without infection (p less than 0.001). In contrast, TNF plasma levels and IL-1 beta production by cord blood leukocytes were decreased in infants with infectious complications alone (both p less than 0.05). These studies suggest that the levels of IL-1 beta, IL-6, and TNF in the cord plasma relate differentially to clinical complications in the perinatal period.