Alteration in regulation of inflammatory response to influenza a virus and endotoxin in suckling rat pups: a potential relationship to sudden infant death syndrome

Abstract

Data increasingly implicate a possible role of immune and inflammatory responses to infection in sudden infant death syndrome (SIDS). We have previously described a dual challenge model that results in pathology, organ damage, vascular collapse and unexplained death similar to that seen in SIDS. In this study, we examined changes in inflammatory cytokine mRNA in the lung and liver and regulation of pathways associated with nitric oxide production. Our data suggest that priming of the immune system by mild viral infection disturbs normal inflammatory response to endotoxin. This results in an increased nitric oxide synthase production, most likely the cause of liver pathology and clotting abnormalities.

Detection of human herpesvirus-6, Epstein-Barr virus and cytomegalovirus in formalin-fixed tissues from sudden infant death: A study with quantitative real-time PCR

“…prone sleeping position) with genetic risk factors (related to immune/infectious responses) could increase the risk of SIDS through unknown underlying mechanisms. Different hypotheses have been postulated as pathogenic and/or associated events for SIDS in regard to asymptomatic virus infection: molecular mimicry, inflammatory-related proteins [8,9], an increase in the activity of bacterial toxins [21], or some kind of immune disregulation (e.g., in an animal model similar to SIDS, asymptomatic viral infection has been suggested that it can boost the effect of non-lethal doses of endotoxin, resulting in an increased nitric oxide synthase production) [22]. However, the intrinsic mechanisms related with these findings remain elusive.…”

Evidence for infection, inflammation and shock in sudden infant death: parallels between a neonatal rat model of sudden death and infants who died of sudden infant death syndrome

“…As previously reported, susceptibility to sudden death in this model was also dependent on the age of the animal. 11,12 Evidence indicated that the death of the rats was due to rapid systemic shock. Endotoxin is known to lower blood pressure and cause shock.…”

Ventilatory Response to Hypoxia during Endotoxemia in Young Rats: Role of Nitric Oxide

“…Elevated NO expression has been found to be associated with organ damage described in autopsy reports of infants who died of SIDS. NOS mRNA up-regulation has been observed after endotoxin administration in animal models for the study of SIDS (13,14).In vitro and in vivo studies indicated that NO has inhibitory properties at the carotid body and that eNOS is primarily responsible for this effect (15,16). Administration of NO donors to the carotid body reduces its chemosensory response to a decrease in oxygen concentration (16).…”

“…Elevated NO expression has been found to be associated with organ damage described in autopsy reports of infants who died of SIDS. NOS mRNA up-regulation has been observed after endotoxin administration in animal models for the study of SIDS (13,14).…”