Nitric oxide induces SOCS-1 expression in human monocytes in a TNF-α-dependent manner

In contrast to the thoroughly characterized mechanisms of positive regulation within cytokine signaling pathways, our knowledge of negative feedback loops is comparatively sparse. We and others have previously reported that IRAK-M down-regulates inflammatory responses to multiple stimuli. In particular, we could show that the nitric oxide (NO) donor, GSNO, induces IRAK-M overexpression in human monocytes. Here we study the expression of another important negative regulator of cytokine signaling, SOCS-1, in human monocytes exposed to GSNO. The NO donor induced significant levels of SOCS-1 mRNA and protein, 6 h and 16 h after stimulation, respectively. Monocytes stimulated with GSNO for longer periods (24 h and 48 h) failed to express IL-6 and IP-10 upon LPS challenge. In addition, and in line with previous reports of NO-mediated induction of TNF-α, we have found that exposure to this cytokine induces SOCS-1 mRNA in human monocytes. A blocking antibody against TNF-α impaired SOCS-1 expression upon GSNO treatment and re-instated IL-6 and IP-10 mRNA levels after LPS challenge in cultures pretreated with the NO donor. We conclude that NO stimulates SOCS-1 overexpression in a pathway at least partially regulated by TNF-α.

Nitric oxide induces SOCS-1 expression in human monocytes in a TNF-alpha-dependent manner

In contrast to the thoroughly characterized mechanisms of positive regulation within cytokine signaling pathways, our knowledge of negative feedback loops is comparatively sparse. We and others have previously reported that IRAK-M down-regulates inflammatory responses to multiple stimuli. In particular, we could show that the nitric oxide (NO) donor, GSNO, induces IRAK-M overexpression in human monocytes. Here we study the expression of another important negative regulator of cytokine signaling, SOCS-1, in human monocytes exposed to GSNO. The NO donor induced significant levels of SOCS-1 mRNA and protein, 6 h and 16 h after stimulation, respectively. Monocytes stimulated with GSNO for longer periods (24 h and 48 h) failed to express IL-6 and IP-10 upon LPS challenge. In addition, and in line with previous reports of NO-mediated induction of TNF-alpha, we have found that exposure to this cytokine induces SOCS-1 mRNA in human monocytes. A blocking antibody against TNF-alpha impaired SOCS-1 expression upon GSNO treatment and re-instated IL-6 and IP-10 mRNA levels after LPS challenge in cultures pretreated with the NO donor. We conclude that NO stimulates SOCS-1 overexpression in a pathway at least partially regulated by TNF-alpha.

Management of neurogenic bladder dysfunction secondary to myelomeningocele

We investigated 55 children, aged from 24 months to 14 years with neurogenic bladder dysfunction secondary to myelomeningocele, by serial urodynamic. They were serially evaluation over 2-5 years. Management consisted of drug therapy together with intermittent vesical catheterization in different combinations on the basis of initial urodynamic assessment. In 5 children with a hypotonic sphincter, it was necessary to implant an artificial sphincter. With this regimen control or frank improvement of micturition was achieved in 53 patients, urodynamic function became normal or improved in 54, and recurrent urinary tract infections persisted only in 5 patients. In the light of these results, we believe that treatment of the neurogenic bladder secondary to myelomeningocele should be determined by initial urodynamic evaluation.

[Treatment of neurogenic bladder secondary to myelomeningocele based on the urodynamic status with intermittent catheterization associated with drugs. Preliminary results]

The follow-up of 36 children with neurogenic urinary bladder, aged from 3.5 months to 12 years is reported. The were serially evaluated with tonometry of detrusor muscle and urethral sphincter. Management consisted in drugs (anticholinergics, alpha-adrenergic agonists and antagonists) associated with intermittent vesical catheterization in different combinations determined by starting urodynamic measurements. With this treatment control of micturition or frank improvement was reached in 91.6% of patients, urodynamic explorations normalized or improved in 94.3% and recurrent urinary infections persisted only in 13.8%. At the view of these results authors believe that treatment of neurogenic bladder secondary to myelodysplasia must be closely dependent on previous urodynamic evaluation.