Pediatric Nephrology

, Volume 21, Issue 3, pp 382–389

Carbon monoxide prevents apoptosis induced by uropathogenic Escherichia coli toxins

Authors

    • Department of Clinical Science, Division of PediatricsKarolinska Institutet
    • Department of Medical Nutrition NOVUMKarolinska University Hospital-Huddinge
  • Roshan Tofighi
    • Division of Toxicology and Neurotoxicology, Department of Environmental MedicineKarolinska Institute
  • Wenjie Bao
    • Microbiology and Tumor Biology CenterKarolinska Institute
  • Olle Aspevall
    • Department of Clinical BacteriologyKarolinska Institute
  • Timo Jahnukainen
    • Department of PediatricsTurku University Hospital
  • Lars E. Gustafsson
    • Department of Physiology and PharmacologyKarolinska Institute
  • Sandra Ceccatelli
    • Division of Toxicology and Neurotoxicology, Department of Environmental MedicineKarolinska Institute
  • Gianni Celsi
    • Department of Clinical Science, Division of PediatricsKarolinska Institutet
Original Article

DOI: 10.1007/s00467-005-2140-1

Cite this article as:
Chen, M., Tofighi, R., Bao, W. et al. Pediatr Nephrol (2006) 21: 382. doi:10.1007/s00467-005-2140-1

Abstract

Urinary tract infections (UTIs) are often caused by Escherichia coli (E. coli). Previous studies have demonstrated that up-regulation of heme oxygenase-1 (HO-1) may trigger a survival mechanism against renal cell death induced by E. coli toxins. The present study analyses the role of carbon monoxide (CO), an end product of HO-1, in the survival mechanism. Moreover, we identified hemolysin as a putative pro-apoptotic toxin in the E. coli supernatant. Tubular cells were incubated with CO in the presence or absence of E. coli toxins. Uropathogenic or transformants of non-pathogenic strains expressing hemolysin were used. We found that the survival pathway during E. coli infection might be activated by HO-1-derived production of CO. The protection by CO was also associated with up-regulation of p21 protein expression. Furthermore, we found that in children with pyelonephritis, all the E. coli strains expressing hemolysin induced apoptosis. In E. coli strains not expressing hemolysin, only 45% of the strains could induce apoptosis. In conclusion, generation of CO elicited by HO-1 could promote survival signaling in renal cells. Hemolysin is one of the secreted toxins that are involved in inducing apoptosis during UTI.

Keywords

Carbon monoxideCell deathHemolysinHeme oxygenase-1Nitric oxidePyelonephritogenic E. coli

Copyright information

© IPNA 2005