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Barrios, C.

Publications and source records attributed to Barrios, C..

2 recordsLinked to original sources

ADAM17 Deletion Protects Against Type1 Diabetes-Associated Kidney Injury by Modulating Inflammatory and Fibrotic Pathways

0BackgroundA Disintegrin and Metalloprotease 17 (ADAM17) is a key sheddase regulating multiple inflammatory and growth factor-related pathways implicated in diabetic kidney disease (DKD). While cell-specific deletion of ADAM17 has shown renoprotective effects, the impact of global ADAM17 ablation in the context of diabetes remains incompletely understood. MethodsWe investigated the effects of tamoxifen-induced global Adam17 deletion in a murine model of type 1 diabetes induced by streptozotocin. Renal function, structural injury, inflammatory responses, stress-related signalling pathways, and fibrotic remodelling were comprehensively assessed and compared between diabetic Adam17 knockout and control mice. ResultsDespite persistent hyperglycaemia and albuminuria, diabetic Adam17 knockout mice exhibited preservation of glomerular filtration rate and marked attenuation of diabetes-associated renal injury. Global Adam17 deletion reduced mesangial expansion and structural damage, limited macrophage infiltration and chemokine expression, and significantly attenuated fibrotic remodelling. At the molecular level, Adam17 deficiency was associated with selective modulation of stress-related signalling pathways, including reduced activation of the PI3K/Akt axis and partial preservation of mitochondrial stress regulators, without evidence of a generalized suppression of cellular stress responses. ConclusionsOur findings demonstrate that global deletion of ADAM17 confers robust protection against diabetes-induced kidney injury through coordinated attenuation of inflammatory activation, stress-related signalling, and fibrotic progression. These results highlight the context-dependent role of ADAM17 in diabetic kidney disease and support the concept that therapeutic strategies targeting ADAM17-related pathways may require tissue- and disease-specific modulation to achieve renoprotective effects.

pathology↗

SARS-CoV-2 infection suppresses ACE2 function and antiviral immune response in the upper respiratory tract of infected patients

There is an urgent need to elucidate the molecular mechanisms underlying the transmissibility and pathogenesis of SARS-CoV-2. ACE2 is a host ectopeptidase with well-described anti-inflammatory and tissue protective functions and the receptor for the virus. Understanding SARS-CoV-2-ACE2 interaction and the expression of antiviral host genes in early infection phase is crucial for fighting the pandemic. We tested the significance of soluble ACE2 enzymatic activity longitudinally in positive nasopharyngeal swabs at two time points after symptom consultation, along with gene expression profiles of ACE2, its proteases, ADAM17 and TMPRRS2, and interferon-stimulated genes (ISGs), DDX58, CXCL10 and IL-6. Soluble ACE2 activity decreased during infection course, in parallel to ACE2 gene expression. On the contrary, SARS-CoV-2 infection induced expression of the ISG genes in positive SARS-CoV-2 samples at baseline compared to negative control subjects, although this increase wanes with time. These changes positively correlated with viral load. Our results demonstrate the existence of mechanisms by which SARS-CoV-2 suppress ACE2 expression and function casting doubt on the IFN-induced upregulation of the receptor. Moreover, we show that initial intracellular viral sensing and subsequent ISG induction is also rapidly downregulated. Overall, our results offer new insights into ACE2 dynamics and inflammatory response in the human upper respiratory tract that may contribute to understand the early antiviral host response to SARS-CoV-2 infection.

immunology↗