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Biology subjects

Marcos, M.

Publications and source records attributed to Marcos, M..

8 recordsLinked to original sources

Urinary extracellular vesicles reveal a sex-specific miRNome profile in alcohol use disorder patients

miRNA-based transcriptomic analysis of extracellular vesicles (EVs) provide a promising strategy for identifying non-invasive biomarkers and understanding complex pathological mechanisms. Recently, however, urinary extracellular vesicles (uEVs) have emerged as a valuable window into molecular alterations. Despite the high morbidity and mortality associated with alcohol use disorder (AUD), the molecular mechanisms underlying its sex-specific differences remain poorly understood. To address this, we characterize for the first time the uEV miRNome in AUD, revealing its sexually dimorphic profile. We employed uEVs from actively drinking AUD patients of both sexes who did not have advanced liver disease, alongside matched controls. Deep sequencing revealed 14 differentially expressed miRNAs in females (e.g., hsa-miR-197-3p, hsa-miR-19b-3p, hsa-miR-505-3p, hsa-miR-625-5p, and hsa-miR-27a-5p) and 6 in males (e.g., hsa-miR-1290, hsa-miR-1246, hsa-miR-450a-5p, and miR-590-5p). Notably, whereas hsa-miR-4787-5p was consistently overexpressed in uEVs from both sexes, it was absent in plasma-derived EVs, highlighting the specificity of the urinary compartment. Remarkably, the miRNA signatures we uncovered reflect the multiorgan impact of AUD. For instance, hsa-miR-1290 and hsa-miR-197-3p point to alcohol-related liver injury and systemic inflammation, whereas hsa-miR-19b-3p and hsa-miR-1246 signal neuroinflammation and neuronal stress. A subset--including hsa-miR-1290, hsa-miR-1246, and hsa-miR-27a-5p--has been implicated in cancer contexts. Collectively, these findings support the uEV miRNome as a promising sex-informed molecular signature of AUD with biomarker and mechanistic relevance.

cell biology↗

Multi-omics integration reveals sex-based differences in the circulating extracellular vesicle lipidome and miRNome of alcohol use disorder patients

Integrated multi-omics and extracellular vesicle (EV) analysis are emerging as powerful, complementary strategies for biomarker discovery. These approaches offer promising tools to enhance early detection, diagnosis, and treatment of alcohol use disorder (AUD). Here we applied an integrated miRNomic and lipidomic approach to analyze plasma EVs from AUD patients and controls of both sexes to gain a comprehensive understanding of the underlying molecular mechanisms. We identified an AUD signature with predictive potential for diagnostic applications. Individual features (e.g., hsa-miR-99b-3p, hsa-miR-556-5p, Cer_NDS-d39:1, and PI18:0_18:2) represented important components; however, the strength of this signature lay in the combined profile rather than isolated markers. We also revealed an AUD-sex signature that provided insight into how biological responses to alcohol differ between females and males (including features such as hsa-miR-1301-3p and PC39:4), which also underscored the power of multi-omic integration. The individual miRNome approach also revealed an opposite functional alteration by sex in various alcohol related systems, such as pathways associated with immunity, oxidative stress, and autophagy. An open-access Shiny web application (https://carpercle.shinyapps.io/SexEVEthOmics/) accompanies this study, providing interactive access to the complete dataset and additional analyses for customized exploration. Together, our findings underscore the added value of multi-omics integration in identifying clinically relevant molecular signatures of disease; this sex-informed approach offers a promising path toward more personalized diagnostic tools and therapeutic strategies in AUD.

bioinformatics↗

Deciphering lipidomics landscape of urine extracellular vesicles in alcohol use disorder patients

Urine extracellular vesicles (EVs) have garnered increasing interest in recent years as, in combination with their lipid content, they represent a potential source of non-invasive biomarkers. Alcohol use disorder (AUD) is one of the most common psychiatric disorders and a significant contributor to morbimortality. Thus, there is growing interest in assessing previous alcohol consumption and evaluating the severity of liver or brain injury, particularly via non-invasive methods. Here, we employed a novel approach based on urine EVs and a highly sensitive lipidomics strategy to characterize lipid species in male AUD patients, as well as to evaluate the differential functional roles and enzymatic activity networks of urine EV lipids. Our results show, for the first time, that the lipidomic profiling of urine EVs in AUD males is characterized by an enrichment of fatty acyls and glycerophospholipids, with FA 22:0 emerging as a potential biomarker. Notably, increased acyl chain saturation and elevated long-chain fatty acids (22-24 carbons) suggest links to AUD-associated inflammation, cancer, and metabolic dysfunction. These findings support an improved understanding of the urine EV lipidome, which could contribute to the identification of novel lipid targets and the discovery of non-invasive biomarkers in AUD.

pathology↗

Adipocyte MKK3 Increases in Human Obesity protecting against Insulin Resistance by p38-beta activation

Obesity is a major global health concern, and a key predisposing factor for insulin resistance and type 2 diabetes mellitus. Adipocytes play a critical role in the development of obesity-induced insulin resistance, with several signaling pathways influencing insulin sensitivity. Among these, p38 MAP kinases are essential for adipose tissue physiology and the regulation of processes such as differentiation, thermogenesis, and inflammation. p38 activation is mediated by the upstream kinases MKK3 and MKK6 in response to inflammatory signals. While MKK6 inhibition promotes browning and thermogenesis and protects against obesity, the role of MKK3 remains unclear. Here, we investigated the function of MKK3 in adipose tissue. In human adipose tissue samples, MKK3 expression was positively correlated with body mass index (BMI) and negatively correlated with glycated hemoglobin, a marker of hyperglycemia. Using whole-body and adipose-specific Mkk3 and p38{beta} knockout mice, we found that Mkk3 activation in adipose tissue during obesity enhances insulin sensitivity. Mechanistically, adipose tissue from Mkk3- or p38{beta}-deficient mice exhibited elevated basal p70S6K activity compared with wild-type controls. This increased p70S6K activity was linked to higher serine phosphorylation of insulin receptor substrate 1 (IRS1) and impaired insulin-stimulated Akt phosphorylation, contributing to worsened insulin resistance. Collectively, our data suggest that activation of the MKK3/p38{beta} signaling axis in adipocytes may protect against high-fat diet-induced insulin resistance and diabetes.

molecular biology↗

Lipid network of plasma extracellular vesicles reveals sex-based differences in the lipidomic profile from patients with alcohol use disorder

Alcohol use disorder (AUD) is one of the most common psychiatric disorders, and the consumption of this substance is considered one of the main causes of preventable deaths worldwide. Lipids play a crucial functional role in cell membranes, however little is known about the role of lipids containing extracellular vesicles (EVs), as regulatory molecules and biomarkers. In this study, a highly sensitive lipidomic strategy is employed to characterize plasma EV lipid species from individuals with AUD, to evaluate differential functional roles and enzymatic activity networks to improve the knowledge of lipid metabolism in the alcohol consumption. Plasma EV lipids from female and male patients with AUD and healthy individuals were analyzed to obtain lipid differential abundance, as well as biological interpretation of LINEX2 lipidomics data, evaluating enzymatic dysregulation through an enrichment algorithm. Our results showed for the first time that females with AUD exhibit greater substrate-product changes in LPC and PC lipids, as well as phospholipases and acyltransferases activity, potentially linked to cancer progression and neuroinflammation. Conversely, males with AUD showed dysregulation in Cer and SM lipid, involving sphingomyelinases, sphingomyelin phosphodiesterase, and sphingomyelin synthase, which could be related with hepatotoxicity. Notably, females with AUD showed LION-terms associated with "positive intrinsic curvature", while males exhibited "negative intrinsic curvature, contributing to vesicle fusion processes. These methodological developments allow a better understanding of lipid metabolism and its regulatory mechanisms, which contributes not only to identify novel lipid targets, but also the discovery of sex-specific clinical biomarkers in the AUD.

pathology↗

Lack of p38 activation in T cells increases IL-35 production and protects against obesity by promoting thermogenesis

Obesity is characterized with low grade inflammation, energy imbalance and impaired thermogenesis. The role of regulatory T cells (Treg) in inflammation-mediated maladaptive thermogenesis has not been well established. We discovered that p38 pathway is a key regulator of T cell-mediated adipose tissue (AT) inflammation and browning. Mice with T cells specific deletion of the p38 activators, MKK3/6, were protected against diet-induced obesity and AT inflammation improving their metabolic profile, higher browning and thermogenesis. We identified IL-35 as a driver of adipocyte thermogenic program through ATF2/UCP1/FGF21 pathway. IL-35 limits CD8+ T cell infiltration and inflammation in AT. Interestingly, we found that IL35 was reduced in visceral fat from obese patients. Mechanistically we showed that p38 controls the expression of IL-35 in human and mouse Treg cells through mTOR pathway activation. Our findings highlight p38 signaling as a molecular orchestrator of AT T cell accumulation and function and identify p38 and IL-35 as promising targets for metabolic diseases.

immunology↗

The immunodominant protein P116 is a passive transporter of cholesterol and other essential lipids

Many human pathogens need to extract lipids from their environment for survival and proliferation. How this is accomplished on a molecular level is largely unknown1. Here, we report a comprehensive structural and functional analysis of the previously uncharacterized protein P116 (MPN_213) from Mycoplasma pneumoniae, a human pathogen responsible for approximately 30% of community-acquired human pneumonia2. Single-particle cryo-electron microscopy of P116 at 3.3 [A] resolution reveals a homodimer with a core domain presenting a previously unseen fold. This fold creates a large cavity of [~]18,000 [A]3 with a hydrophobic internal surface that is accessible to solvent. Within the cavity ligands with a length of 10-19 [A] and a width of 4 [A] could be observed. These ligands were identified as the essential lipids phosphatidylcholine, sphingomyelin and cholesterol using mass spectrometry. When the cavity is emptied, the protein undergoes an extensive conformational change that can no longer accommodate lipids. When emptied P116 is incubated with high-density lipoproteins (HDLs) a net transfer of cholesterol is demonstrated by a radioactivity experiment and cryo-electron microscopy resolves a complex between P116 and HDL. Taken together, our results reveal the mechanism by which P116 extracts essential lipids from the host environment and possibly then delivers them into the membrane by a wringing movement. This mechanism may be precedential for other cholesterol-auxotrophic bacteria.

microbiology↗

Rituximab treatment for IgA vasculitis: A systematic review

ObjetivesImmunoglobulin A vasculitis (IgAV) is an inflammatory disease with a controversial treatment based in corticosteroids as first line. To review cases of patients with IgA vasculitis (IgAV) treated with rituximab (RTX) and assess disease characteristics, treatment efficacy and safety.\n\nMethodsWe conducted a systematic literature review according to PRISMA guidelines. We searched Pubmed, Web of Science, Embase and Scopus, selecting articles with information on IgAV and RTX treatment up to February 2019, with no language limitations. We extracted data on patient characteristics, disease evolution, treatment safety and efficacy. We created a database and analyzed it using statistical software package SPSS v 22.0.\n\nResultsWe extracted clinical data for 43 IgAV patients treated with RTX. Distribution by sex was similar, and the median age at diagnosis was 16 (range 2 months to 70 years). The majority of patients were diagnosed at a pediatric age (24 patients under 18, 55.81%). The time of disease evolution until RTX administration greatly varied. An important number of patients suffered renal complications (86%) before RTX treatment. The frequency of adverse effects from RTX was low (7%, hypersensitivity with no treatment interruption). In terms of disease evolution, 41 patients (95.3%) presented clinical improvement, 15 patients had recurrence after initial remission (34.9%) and 34 patients (79.1%) achieved full remission after completing treatment. None of the patients treated with RTX and included in our systematic review died.\n\nConclusionsRTX is efficacious in patients with IgAV. A high percentage of patients achieved complete remission with a favorable safety profile.

pharmacology and toxicology↗