Bacterial DNA and RNA induce rat cardiac myocyte contraction depression in vitro.
Sepsis and septic shock, the systemic immunologic and pathophysiologic response to overwhelming infection, are associated with perturbation of a variety of metabolic cell pathways and with multiple organ failure (MOF) including cardiac depression. This depression has been attributed to the effect of several circulating and locally produced proinflammatory mediators. Recent data suggest that bacterial nucleic acids can produce profound systemic inflammatory responses characterized by circulatory shock in intact animals. In this study, bacterial DNA and RNA derived from pathogenic clinical S. aureus and E. coli isolates are shown to induce early concentration-dependent depression of maximum extent and peak velocity of contraction of electrically paced neonatal rat ventricular myocytes in culture. Significant but more modest depression was generated by a nonpathogenic E. coli isolate. Pretreatment with a DNase or RNase abrogated this effect. Further, synthetic, double-stranded RNA (dsRNA) also induced concentration-dependent depression of myocyte contraction, with the effect also being prevented by pretreatment with RNase. These data suggest that bacterial DNA and RNA may contribute to myocardial depression during bacterial sepsis and septic shock.
Paladugu
Bhanu
B
Division of Cardiovascular Disease and Critical Care Medicine, Cooper Hospital, University Medical Center, Robert Wood Johnson Medical School, Camden, New Jersey 08103, USA.
Kumar
Anand
A
Parrillo
Joseph E
JE
Der
Sandy
S
Osman
Jailan
J
Mensing
Joel
J
Falvo
Lisa
L
Xu
Xiulong
X
Kumar
Aseem
A
D000818:Animals; D002478:Cells, Cultured; D004269:DNA, Bacterial / Q000494:pharmacology*; D004926:Escherichia coli / Q000235:genetics; D051379:Mice; D009200:Myocardial Contraction / Q000187:drug effects*; D032383:Myocytes, Cardiac / Q000166:cytology / Q000187:drug effects* / Q000502:physiology*; D012329:RNA, Bacterial / Q000494:pharmacology*; D051381:Rats; D012772:Shock, Septic / Q000150:complications; D013211:Staphylococcus aureus / Q000235:genetics
D004269:DNA, Bacterial; D012329:RNA, Bacterial