Severe dengue is a global health threat, affecting 4 billion people, with nearly 1 million hospitalizations during epidemics and around 25,000 annual deaths. Severe dengue presentations are characterized by vascular leakage, hemorrhagic manifestations, and shock, which can lead to multiorgan failure. Recent studies highlight the crucial role of extracellular vesicles (EVs) in the pathogenesis of dengue, influencing immune response and disease progression. EVs, nanometric structures secreted by cells, mediate viral dissemination, immune modulation, and endothelial dysfunction by transporting biomolecules such as microRNAs (miRNAs) and viral proteins. Infected cell-derived EVs carry viral components, including NS protein and miRNAs like miR-21 and miR-126-5p, which compromise endothelial integrity and activate immune pathways such as Toll-like receptor, NF-κB, and JAK-STAT signaling. This, together with the immune response, leads to the release of pro-inflammatory cytokines, including TNF-α, IL-1β, IL-6, and IFN-γ. EVs also facilitate viral immune evasion by suppressing antiviral responses. Recent analyses of miRNAs within EVs suggest their potential as biomarkers for disease progression. Differentially expressed miRNAs in circulating EVs correlate with severe outcomes, providing tools for risk stratification and therapeutic monitoring. Advanced techniques, such as nanoparticle tracking analysis and flow cytometry, allow precise EV characterization, supporting their integration into clinical applications.

This study aimed to investigate whether monocyte dysregulation and hyperinflammation serve as predictive markers for mortality in young patients with SARS-CoV-2 severe pneumonia. A prospective cohort study was conducted in a tertiary-level public University Hospital in Colombia. Forty young adults (18–50 years of age) with severe pneumonia and SARS-CoV-2 infection confirmed by qPCR, were enrroled. Serum cytokines and the monocyte phenotype profile, including PDL1/HLA-DR expression, were determined during the first 24 h of hospitalization. Routine laboratory parameters were measured throughout patient follow-up until either death or hospital discharge. We also included a cohort of twenty-five healthy control subjects. Elevated levels of IL-10, IL-8, and IL-6 cytokines emerged as robust predictors of mortality in young adults with severe pneumonia due to SARS-CoV-2 infected. A descriptive analysis revealed a cumulative mortality rate of 30 % in unvaccinated and ICU-admitted patients. Patients who died had significantly lower expression of HLA-DR on their classical monocytes subsets (CD14⁺CD16⁻) than survivors and healthy controls. Lower expression of HLA-DR was associated with greater clinical severity (APACHE≥12) and bacterial coinfection (relative risk 2.5 95%CI [1.18–5.74]). Notably, the expression of HLA-DR in 27.5 % of CD14⁺/CD16^- monocytes was associated with a significantly lower probability of survival. The early reduction in HLA-DR expression within classical monocytes emerged as an independent predictor of mortality, irrespective of comorbidities. Together with PD-L1 expression and cytokine alterations, these findings support the notion that monocyte immunosuppression plays a fundamental role in the pathogenesis and mortality of young patients infected with SARS-CoV-2. These findings hold significant implications for risk assessment and therapeutic strategies in managing critically ill young adults with SARS-CoV-2 infection.

Irisin, a myokine generated through the proteolytic cleavage of fibronectin type III domain-containing protein 5 (FNDC5), has been increasingly recognized as a critical mediator of the salutary effects of physical exercise on metabolic homeostasis, energy metabolism, and the regulation of inflammatory, oxidative, and fibrotic pathways. Recent investigations have delineated a significant association between irisin levels and renal pathophysiology, particularly within the context of chronic kidney disease. Emerging evidence suggests that irisin may play a modulatory role in renal function, with particular relevance to diabetic nephropathy and acute kidney injury. Therefore, this mini-review consolidates current findings on the mechanistic underpinnings of irisin's involvement in renal pathophysiology, elucidating its intricate interplay with kidney disease. Additionally, we highlight the potential of irisin as a promising biomarker and therapeutic target in nephrology.

Current evidence show that exercise has beneficial effects on skeletal muscle function in individuals with chronic kidney disease (CKD). The STAT3 signaling pathway and the apelin axis (apelin receptor, APLNR- and ligands, -apelin and/or -elabela), participate in the processes of kidney inflammation and fibrosis and both may be involved in muscle wasting during CKD. Herein we report that STAT3 pathway and APLNR are in fact involved in the muscle impairment concomitant to CKD in experimental model and in adult individuals with CKD. Male BALB/c mice were first submitted to an 8-week ladder climbing resistance training (RT) protocol and further were submitted to doxorubicin-induced experimental CKD with or without use of the STAT3 inhibitor (Stattic). The GSE157712 dataset was used to assess the muscle transcriptome profile of CKD patients. Bioinformatics' analysis of gene set enrichment analysis (GSEA) and gene ontology (GO) were performed and the APLNR was found to be a central component of muscle response over kidney stress. Mice from the RT protocol showed a protective effect of blocking STAT3 against kidney and muscle injury markers, while both CKD individuals and CKD mice reported alterations in the APLNR muscle expression. In conclusion, the muscle tissue function is affected during CKD, which can be attenuated by a protective and synergistic effect of exercise and STAT3 inhibition. Thus, APLNR appears as a key gene associated with muscle dysfunction in CKD patients and its muscle expression can be regulated by resistance exercise.