Dysregulated NO/PDE5 signaling in the sickle cell mouse lower urinary tract: Reversal by oral nitrate therapy

Autor(es)

Musicki, Biljana ^[1] ; Anele, Uzoma A. ^[1] ; Campbell, Jeffrey D. ^[1] ; Karakus, Serkan ^[1] ; Shiva, Sruti ^[2] ; Silva, Fabio H. ^[1] ; Burnett, Arthur L. ^[1]

Afiliação do(s) autor(es)

^[1] Johns Hopkins Univ, Sch Med, James Buchanan Brady Urol Inst & Dept Urol, Baltimore, MD - USA

^[2] Univ Pittsburgh, Vasc Med Inst, Dept Pharmacol & Chem Biol, Pittsburgh, PA - USA

• Tipo de documento: Artigo Científico
• Fonte: Life Sciences; v. 238, DEC 1 2019.
• Citações Web of Science: 0

Resumo

Aims: Nitric oxide (NO) has a critical, but not well understood, influence in the physiology of the lower urinary tract. We evaluated the effect of NO/phosphodiesterase (PDE)5 signaling in voiding dysfunction in the sickle cell disease (SCD) mouse, characterized by low NO bioavailability. Main methods: Adult SCD (Sickle) and wild-type (WT) male mice were treated daily with sodium nitrate (10 mM) or vehicle. After 18 days, blood was obtained for nitrite measurement, urethra was collected for organ bath study, and bladder and urethra were collected for Western blot analysis of PDE5 phosphorylation (Ser-92) (activated form). Non-anesthetized mice underwent evaluation of urine volume by void spot assay. eNOS phosphorylation (Ser-1177) and nNOS phosphorylation (Ser-1412) (positive regulatory sites) were evaluated in the bladder and urethra of untreated mice. Key findings: Sickle mice exhibited decreased eNOS, nNOS, and PDE5 phosphorylation in the bladder and urethra, decreased plasma nitrite levels, increased relaxation of phenylephrine-contracted urethral tissue to an NO donor sodium nitroprusside, and increased total urine volume, compared with WT mice. Nitrate treatment normalized plasma nitrite levels, relaxation of urethra to sodium nitroprusside, PDE5 phosphorylation in the urethra and bladder, and urine volume in Sickle mice. Significance: Derangement in PDE5 activity associated with basally low NO bioavailability in the bladder and urethra contributes to the molecular basis for voiding abnormalities in Sickle mice. Inorganic nitrate supplementation normalized voiding in Sickle mice through mechanisms likely involving upregulation of PDE5 activity. These findings suggest that interventions targeting dysregulatory NO/PDE5 signaling may ameliorate overactive bladder in SCD. (AU)

• Processo FAPESP: 17/08122-9 - Priapismo e disfunção miccional na Anemia Falciforme: fisiopatologia e novos candidatos a fármacos
• Beneficiário: Fábio Henrique da Silva
• Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores
• Processo FAPESP: 18/06243-6 - Priapismo e disfunção miccional na anemia falciforme: fisiopatologia e novos candidatos a fármacos
• Beneficiário: Fábio Henrique da Silva
• Modalidade de apoio: Bolsas no Brasil - Jovens Pesquisadores