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Fuertes, M.

Publications and source records attributed to Fuertes, M..

2 recordsLinked to original sources

Mitochondrial dysfunction: unraveling the elusive biology behind anti-TNF response during ulcerative colitis

BackgroundRecent studies hint at mitochondrial genes influencing UC patient response to anti-TNF treatment. We evaluated this hypothesis by following a targeted strategy to identify gene expression that captures the relationship between mitochondrial dysregulation and response to treatment. Our objective was to initially examine this relationship in colon samples and subsequently assess whether the resulting signal persists in the bloodstream. MethodsWe analyzed the transcriptome of colon samples from an anti-TNF treated murine model characterized by impaired mitochondrial activity and treatment resistance. We then transferred the findings that linked mitochondrial dysfunction and compromised treatment response to an anti-TNF treated UC human cohort. We next matched differential expression in the blood using monocytes from peripheral blood of controls and IBD patients, and we evaluated a classification process at baseline with whole blood samples from UC patients. ResultsIn human colon samples, the derived gene-set from the murine model showed differential expression, primarily enriched metabolic pathways, and exhibited similar classification capacity as genes enriching inflammatory pathways. Moreover, the evaluation of the classification signal using blood samples from UC patients at baseline highlighted the involvement of mitochondrial homeostasis in treatment response. ConclusionOur results highlight the involvement of metabolic pathways and mitochondrial homeostasis in determining treatment response and their ability to provide promising classification signals with detection levels in both colon and bloodstream.

immunology↗

Role of canonical and non-canonical cAMP Sources in CRHR2α-dependent Signaling

Hippocampal neurons exhibit activation of both the conventional transmembrane adenylyl cyclases (tmACs) and the non-canonical soluble adenylyl cyclase (sAC) as sources of cyclic AMP (cAMP). These two cAMP sources play crucial roles in mediating signaling pathways downstream of CRHR1 in neuronal and neuroendocrine contexts. In this study, we investigate the involvement of both cAMP sources in the molecular mechanisms triggered by CRHR2. Here we provide evidence demonstrating that UCN1 and UCN3 exert a neuritogenic effect on HT22-CRHR2 cells, which is solely dependent on the cAMP pool generated by sAC and PKA activity but independent of ERK1/2 activation. Through the characterization of the effectors implicated in neurite elongation, we found that CREB phosphorylation and c-Fos induction rely on PKA activity and ERK1/2 phosphorylation, underscoring the critical role of signaling pathway regulation. These findings strengthen the concept that localized cAMP microdomains actively participate in the regulation of these signaling processes.

molecular biology↗