Fonds de la Recherche Scientifique - F.R.S.-FNRS, sponsor, Fonds Léon Fredericq, sponsor, Centre Hospitalier Universitaire de Liège - CHU Liège, sponsor, GIGA‐Research - GIGA‐R, research center
BACKGROUND AND AIMS: Dual Specificity Phosphatase 3 (DUSP3) is a positiveregulator of the innate immune response in case of sepsis, but its role in the ischemicdamage is unknown. Here, we study (i) whether and where DUSP3 is expressed in therenal parenchyma, and (ii) whether its genetic deletion in Dusp3 systemic knock-out(Dusp3-/-) mice attenuates the I/R-associated inflammation and injury.METHOD: Experiment 1: Ten C57BL/6 male WT and Dusp3-/- mice underwent rightnephrectomy and left renal ischemia for 30 minutes followed by a reperfusion of 48hours. Blood and kidneys were collected. Renal function was assessed upon I/Rbiomarkers, i.e. blood urea nitrogen (BUN) and creatinine (SCr). Expressions ofinflammatory and immune markers were comparatively quantified at both mRNA(real-time qPCR) and protein (immuno-blotting and –staining) levels in ischemic vs.non-ischemic kidneys in Dusp3 WT vs. KO mice.Experiment 2: Ten C57BL/6 male WT and Dusp3-/- mice were anesthetized. RenalDoppler ultrasound was performed to assess the renal resistivity index (RRI). Theexpression of CD31 and VEGF vascular markers was quantified by the means of real time qPCR and and immuno-staining (FiJi software).RESULTS: Experiment 1: An immuno-reactive signal for DUSP3 was detected in theglomeruli (in co-localization with nephrin) and in Meca-32-positive endothelial cells ofboth outer and inner medulla of mouse non-ischemic WT kidneys. No significantimmunoreactivity for DUSP3 was detected in Dusp3-/- kidneys. Following renal I/R, themRNA level of Dusp3 was increased 1.8-fold compared to baseline (p<0.001).Immunoblot quantifications showed a 77-fold increased expression of DUSP3 postrenal I/R. Serum levels of I/R biomarkers were significantly lower in Dusp3-/- comparedto WT mice following renal I/R (BUN: 78.4633.7 vs. 258.96162.9mg/dL; SCr:0.160.07 vs. 0.860.9 mg/dL; p<0.01). At mRNA levels, Dusp3-/- ischemic kidneysshowed a significantly decreased expression level of CD11b, TNF-a, KIM-1, IL-6, IL-1band caspase-3 compared to controls. The numbers of PCNA-, F4-80- and CD11b positive cells were significantly reduced in Dusp3-/- vs WT renal parenchyma post I/R.Experiment 2: The RRI non-invasively measured by ultrasound was lower in Dusp3-/-group compared to controls (0.566 0.03 vs. 0.6660.02; p<0.001). The Dusp3-/- non ischemic kidneys were characterized by a 1.8-fold increased surface of CD31-positivecells compared to WT kidneys (p<0.001). At mRNA levels, the Dusp3-/- kidneysshowed significantly increased basal levels of CD31 and VEGF compared to controls.CONCLUSION: The genetic deletion of DUSP3 is associated with (i) increased renalvascular density, (ii) decreased RRI and (iii) nephroprotection against renal I/R injury.
نوع الوثيقة:
conferencePaper
اللغة:
English
العلاقة:
58ème congrès de "The European Renal Association – European Dialysis and Transplant Association", Berlin, Allemagne (du 5 juin au 8 juin 2021)
