https://hdl.handle.net/10481/29113 2026-04-11T04:46:53Z https://hdl.handle.net/10481/112582 Novel epigenetic marks of insulin resistance trajectories in a longitudinal study of childhood obesity Anguita-Ruiz, Augusto; Torres-Martos, Álvaro; Bustos-Aibar, Mireia; Setó-Llorens, Adriá; Ruiz-Ojeda, Francisco Javier; Moreno, Luis A.; Gil, Ángel; Gil-Campos, Mercedes; Bueno, Gloria; Leis, Rosaura; Alcalá-Fdez, Jesús; Aguilera, Concepción M. Background: Childhood obesity is a major global public-health challenge. Insulin resistance (IR) is a critical driver of later cardiometabolic alterations. A comprehensive understanding of the molecular mechanisms underlying the initial development of childhood IR is essential for timely prevention and intervention. In this study, we aimed to assess the association between IR and blood DNA methylation in a longitudinal study from childhood into adolescence. Methods: The PUBMEP study included a longitudinal core of 90 children with paired blood samples collected at both pre-pubertal and pubertal stages. For cross-sectional analyses, this sample was expanded to 99 pre-pubertal and 129 pubertal participants. IR status was defined according to clinically relevant sex- and pubertal stage specific HOMA-IR cut-offs, as recommended by pediatric expert clinicians. Genotype data was obtained with the Infinium Global Screening Array, and blood DNA methylation sites with the Infinium MethylationEPIC BeadChip. Epigenome-wide associations with IR status and trajectories were tested using linear models in the longitudinal and cross-sectional sets. FDR-adjusted significant CpG sites were assessed with sex- and age-standardised cardiometabolic z-scores (adiposity, lipids, blood pressure, glycaemia and IR) at each stage. mQTL analyses were performed to identify genetic variants that drive IR-associated methylation signals. Results: We identified 120 CpG sites related to obesity-associated IR in the context of pubertal transition that remained significant after global FDR correction (FDR < 0.05). These CpG sites showed distinct methylation profiles that tracked IR trajectories from prepuberty to puberty, with consistent differences across children whose IR improved, worsened or remained stable, with several of them also related to cardiometabolic traits at pubertal stage, including adiposity measures, blood pressure and glycaemic indices. Among the FDR-significant CpG sites with biological relevance for IR, methylation at CpG sites annotated to SLC2A9, PEPD, TSC2, EGLN3, EHD2 and VASN showed consistent associations with pubertal HOMA-IR z-score and, for several loci, with adiposity and blood pressure measures, with methylation changes paralleling IR worsening, improvement or stability across puberty. An mQTL look-up in GoDMC identified 25 cis SNP CpG associations corresponding to 20 of the 120 CpG sites, including CpG sites in SLC2A9 and TSC2, indicating that only a fraction of these IR-associated CpG sites is likely to be partly influenced by nearby genetic variants. Conclusion: This longitudinal EWAS in children with obesity shows that specific blood DNA methylation signatures mirror IR status and track its evolution across the pubertal transition, with opposing methylation trajectories distinguishing improving from persistent IR. The identification of CpG sites at VASN, SLC2A9, PEPD, EGLN3, EHD2 and TSC2 links IR trajectories to pathways involved in vascular signalling, urate transport, extracellular matrix remodelling, and hypoxia sensing and nutrient signalling. Complementary mQTL analyses suggest that while some of this epigenetic variation is influenced by local genetic factors, a substantial component is likely acquired in response to metabolic and external exposures. If replicated and functionally characterised, these findings may help refine our understanding of the early molecular architecture of obesity-related IR and inform future strategies for cardiometabolic risk assessment and timing of preventive interventions. https://hdl.handle.net/10481/111882 MemoryCells in Atopic Dermatitis: Paving the Way to Disease Modification Dominguez Lopez, Raquel; Aranda Clemente, Carlos José; Gómez de la Fuente, Enrique; Pérez García, Bibiana; Perez Bootello, Javier; Abbad Jaime de Aragon, Carlota; González Cantero, Álvaro; Berna Rico, Emilio Atopic dermatitis (AD) is a chronic relapsing inflammatory skin disease in which persis tence of immunological memory underlies disease recurrence and progression toward atopic comorbidities. Evidence indicates that pathogenic tissue-resident memory T cells (TRM), including Th2- and Th22-skewed subsets, among others, persist in both lesional and clinically resolved skin and rapidly re-initiate inflammation through production of IL-4, IL-13, IL-22 and IL-31, promoting barrier dysfunction and pruritus. In parallel, circulating CLA+ memory T cells retain skin-homing capacity and contribute to flare reacti vation, while IgG1+CD23 IL-4Rα+ type-2 memory B cells (MBC2) constitute a reservoir for high-affinity IgE production, linking cutaneous inflammation with allergic comorbidities. These adaptive memory compartments are sustained by epithelial alarmins, dendritic cell–derived chemokines such as CCL17, CCL22 and CCL18, and the OX40/OX40L costim ulatory pathway, which promotes differentiation, survival and tissue retention of memory T cells. Clinical and transcriptomic studies show how, although IL-4/IL-13 blockade reduces circulating type-2 responses, Th2A cells, Tc2 cells and activated dendritic cells can persist in clinically resolved skin, providing a mechanistic basis for relapse after treatment with drawal. Together, these findings support the relevance of targeting memory-imprinting pathways as a promising mechanism to achieve durable disease modification in AD. https://hdl.handle.net/10481/110740 Intestinal epithelial deletion of the glucocorticoid receptor NR3C1 alters expression of inflammatory mediators and barrier function Aranda Clemente, Carlos José; Arredondo-Amador, María; Ocón, Borja; Lavín, José Luis; Aransay, Ana María; Martínez Augustín, María Olga; Sánchez De Medina López-Huertas, Fermín Glucocorticoids (GC) are important hormones involved in the regulation of multiple physiological functions. GC are also widely used antiinflammatory/immunosuppresant drugs. GC are synthesized by the adrenal cortex as part of the hypothalamus-pituitary-adrenal axis, and also by intestinal epithelial cells, among other peripheral sites. GC are one of the main therapy choices for the exacerbations of inflammatory bowel disease, but they are not useful to prolong remission, and development of tolerance with secondary treatment failure is frequent. Thus GC actions at the intestinal epithelial level are of great importance, both physiologically and pharmacologically. We generated a tamoxifen inducible NR3C1IEC model to study the effects of GC on epithelial cells in vivo. Nr3c1 deletion in epithelial cells of the small intestine and colon was associated with limited colonic inflammation at 1 week postdeletion, involving augmented epithelial proliferation and mucus production, plus local and systemic immune/inflammatory changes. This phenotype regressed substantially, but not completely, after 2 weeks. The mechanism may involve augmented inflammatory signaling by epithelial cells and/or defective barrier function. We conclude that the epithelial GC receptor plays a significant role in colonic homeostasis in basal conditions, but its deficiency can be compensated in the short term. Future studies are required to assess the impact of Nr3c1 deletion in other conditions such as experimental colitis. This work was supported by funds from the Ministry of Economy and Competitivity, partly with Fondo Europeo de Desarrollo Regional (FEDER) funds (BFU2014-57736-P, AGL2014-58883-R, SAF2017-88457-R, and AGL2017-85270-R), and by Junta de Andalucía (CTS235 and CTS164). B.O., C.J.A., and M.A.-A. were supported by fellowships from the Ministry of Education. Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd) is funded by Instituto de Salud Carlos III. Center for Cooperative Research in Biosciences (CIC bioGUNE) support was provided by the Basque Department of Industry, Tourism, and Trade (Etortek and Elkartek Programs), the Innovation Technology Department of Bizkaia County, CIBERehd Network, and Spanish Ministry of Economy and Competitiveness (MINECO) Severo Ochoa Excellence Accreditation (SEV-2016-0644). The authors have received funds and/or support from Amino Up Chemical, Pfizer, Hospira, Sanofi, Biosearch Life, Bioiberica and APC Europe. https://hdl.handle.net/10481/110739 Exogenous leptin reinforces intestinal barrier function and protects from colitis Rivero Gutiérrez, Belén; Aranda Clemente, Carlos José; Ocón, Borja; Arredondo-Amador, María; Martínez Augustín, María Olga; Sánchez De Medina López-Huertas, Fermín Besides its function controlling energy expenditure and food intake, leptin is an important modulator of inflammatory responses. The role of leptin in intestinal inflammation remains controversial, since both pro-inflammatory and anti-inflammatory effects have been reported. This study was carried out to further understand leptin contribution in the inflamed intestinal mucosa. Exogenous PEG-leptin or saline solution was given to C57BL/6 mice for two weeks. After 1 week, acute colitis was induced to C57BL/6 mice using dextran sulfate sodium (DSS) in drinking water. The severity of colitis, inflammatory parameters and mucosal barrier function were evaluated. Overall our results indicate that colitis was less severe in mice receiving leptin, as shown by a decrease in rectal bleeding, epithelial damage and colon inflammatory markers, and improved diarrhea. Leptin-treated mice displayed an increase in the expression of tight junction proteins and proliferative expression markers in colon, indicating a reinforcement in the mucosal barrier function induced by leptin administration. PEG-leptin treatment conferred protection to mice in the DSS model of colitis by reinforcing mucosal barrier function. The authors are thankful to Mercedes González and other laboratory members for their assistance, as well as to Dr. Diego Pérez Tilve (University of Cincinnati). This work was supported by the Ministerio de Economía y Competitividad (SAF2011-22922, SAF2011-22812, BFU2014-57736-P, AGL2014-58883-R) and Junta de Andalucía (CTS164, CTS235). BRG, CJA, BO and MAA are funded by Ministry of Education. CIBERehd is funded by the Instituto de Salud Carlos III. https://hdl.handle.net/10481/110691 CD23+IgG1+ memory B cells are poised to switch to pathogenic IgE production in food allergy Ota, Miyo; Hoehn, Kenneth B.; Fernandes-Braga, Wesllley; Ota, Takayuki; Aranda, Carlos J.; Friedman, Sara; Miranda-Waldetario, Mariana G.C.; Redes, Jamie; Suprun, Maria; Grishina, Galina; Sampson, Hugh A.; Malbari, Alefiyah; Kleinstein, Steven H.; Sicherer, Scott H.; Curotto de Lafaille, Maria A.