Endogenous glucocorticoids attenuate Shiga toxin‐2‐induced toxicity in a mouse model of haemolytic uraemic syndrome

• Published in: Clinical and experimental immunology Vol. 131; no. 2; pp. 217 - 224
• Main Authors: GÓMEZ, S. A., FERNÁNDEZ, G. C., VANZULLI, S., DRAN, G., RUBEL, C., BERKI, T., ISTURIZ, M. A., PALERMO, M. S.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Science Ltd 01-02-2003; Blackwell; Oxford University Press; Blackwell Publishing Inc
• Subjects: Adrenal Glands - physiopathology; Animals; Biological and medical sciences; Corticosterone - blood; Disease Models, Animal; Drug Administration Schedule; General aspects; glucocorticoid receptors glucocorticoids HUS neutrophils Stx2; Glucocorticoids - physiology; Hemolytic-Uremic Syndrome - microbiology; Hemolytic-Uremic Syndrome - pathology; Hemolytic-Uremic Syndrome - physiopathology; Hormone Antagonists - pharmacology; Infection pathogenesis; Infectious diseases; Kidney - pathology; Male; Medical sciences; Mice; Mice, Inbred BALB C; Mifepristone - pharmacology; Original; Receptors, Glucocorticoid - antagonists & inhibitors; Shiga Toxin 2 - antagonists & inhibitors; Shiga Toxin 2 - toxicity; Survival Rate; Urea - blood; Kidney disease; Animal model; Correlation; Urinary system disease; Hemolytic uremic syndrome; Steroid hormone; Toxicity; Rodentia; glucocorticoid receptors glucocorticoids HUS neutrophils Stx2; Hemopathy; Glucocorticoid; Infection; Vertebrata; Hemolytic anemia; Mammalia; Endogenous; Mouse; Animal; Adrenal hormone; Renal failure; Bacteriosis; Complication; Shiga like toxin; Immune system
• ISSN: 0009-9104; 1365-2249
• DOI: 10.1046/j.1365-2249.2003.02057.x

SUMMARY
The concept that during an immune challenge the release of glucocorticoids (GC) provides feedback inhibition on evolving immune responses has been drawn primarily from studies of autoimmune and/or inflammatory processes in animal models. The epidemic form of haemolytic uraemic syndrome (HUS) occurs secondary to infection with Gram‐negative bacteria that produce Shiga toxin (Stx). Although Stx binding to the specific receptors present on renal tissue is the primary pathogenic mechanism, inflammatory or immune interactions are necessary for the development of the complete form of HUS. The aim of this study was to investigate the influence of endogenous GC on Stx‐toxicity in a mouse model. Stx2 was injected into GC‐deprived mice and survival rate, renal damage and serum urea levels were evaluated. Plasma corticosterone and cytosolic GC receptor (GR) concentration were also determined at multiple intervals post‐Stx2 treatment. Higher sensitivity to Stx2 was observed in mice lacking endogenous GC, evidenced by an increase in mortality rates, circulating urea levels and renal histological damage. Moreover, Stx2 injection was associated with a transient but significant rise in corticosterone secretion. Interestingly, 24 h after Stx inoculation significant increases in total GR were detected in circulating neutrophils. These results indicate that interactions between the neuroendocrine and immune systems can modulate the level of damage significantly during a bacterial infection.