- Research Article
- 10.1186/s10020-026-01428-1
Glucagon secretion by pancreatic alpha-cells requires an intact tubulin-cytoskeleton-primary cilium axis
- Feb 10, 2026
- Molecular Medicine
- Elena Casanueva-Álvarez + 12 more +12
Publications from 2021 to 2026
Showing 10 of 166 papers
Glucagon secretion by pancreatic alpha-cells requires an intact tubulin-cytoskeleton-primary cilium axis
MiR-7 inhibits progression of glioblastoma by impairing autophagy resolution, energy metabolism and ECM remodeling
BackgroundDue to the poor prognosis of patients suffering malignant brain tumors such as glioblastoma multiforme (GBM), the search for new therapeutic strategies with more efficacy and higher survival rate is of utmost urgency. Growing evidence suggests that alterations in autophagy and metabolism critically contribute to the pathogenesis and progression of GBM. In this context, microRNAs are known to regulate autophagy and associated cellular functions, which point them as promising therapeutic candidates. We previously established the role of miR-7 in regulating relevant metabolic pathways related to insulin signaling and cholesterol homeostasis.MethodsBioinformatics analysis was performed to identify miR-7 target genes potentially involved in the regulation of metabolism and cellular processes related to GBM. Ectopic expression of miR-7 was assessed to investigate its role in macroautophagy and energy metabolism. In vivo, miR-7 levels were restored in a mouse GBM xenograft model to evaluate its potential therapeutic effect in already established tumors. Additional mechanistic approaches, including transcriptomics, bioinformatics, and histopathological analyses, indicate that miR-7 modifies the tumor phenotype by altering key genes involved in extracellular matrix (ECM) remodeling in vivo.ResultsHerein, we unveiled new conceptual and functional pathophysiological avenues in GBM, with potential therapeutic implications, by demonstrating a novel dual role of miR-7 on the regulation of metabolism, through the impairment of the mitochondrial function and glycolysis, and autophagy, by inducing the initiation process through the regulation of PI3K/AKT/mTORC1 signaling, while blocking later stages via posttranscriptional inhibition of two key SNARE proteins, STX17 and SNAP29. Furthermore, in vivo studies using a preclinical model showed that miR-7 overexpression in already established GBM tumors promotes a significant inhibition of tumor size and progression and replicates the metabolic defects found in vitro. Moreover, our novel findings indicate that miR-7 modifies the tumor phenotype by promoting alterations in its mechanism of extracellular matrix remodeling in vivo.ConclusionAltogether, our study provides solid, convincing evidence demonstrating that miR-7 might be used as a promising therapeutic target for GBM, paving the way to explore its potential as novel biomarker and actionable target candidate for this lethal cancer.Supplementary InformationThe online version contains supplementary material available at 10.1186/s13046-025-03504-6.
Read moreDecreased expression of insulin-degrading enzyme increases gluconeogenesis and glucose production in cultured hepatocytes administered with glucagon
Insulin-degrading enzyme (IDE) is a protein with proteolytic and non-proteolytic functions that regulates glucose homeostasis. In the fasted state, glucagon regulates glycemia through induction of hepatic gluconeogenesis. The rate of hepatic gluconeogenesis is elevated in subjects with type 2 diabetes (T2D) compared with healthy subjects. Interestingly, subjects with T2D show decreased expression of hepatic IDE. However, the role of IDE on the regulation of hepatic gluconeogenesis is completely unknow. We hypothesize that IDE deficiency alters glucagon signaling and thereby gluconeogenesis. To test this hypothesis, we used mouse liver tissues and cultured hepatocytes with total or partial IDE deficiency. The glucagon signaling pathway, expression of gluconeogenic genes, glucose production, and transcriptomic analysis were performed in control and IDE-KO hepatocytes. Total or partial loss of IDE in liver tissues or cultured mouse hepatocytes resulted in lower levels of the glucagon receptor (GCGR) and the cAMP-response element binding protein (CREB). However, glucagon stimulation increased the phosphorylation of CREB, despite lower levels of cAMP in IDE-deficient mouse hepatocytes. The activation of CREB was associated with an upregulation of the gluconeogenic genes Pck1 and G6pc (~ 200% and ~ 70% respectively) and higher glucose production in IDE-deficient mouse hepatocytes. Finally, genetic depletion of IDE in HepG2 hepatocytes led to upregulation of genes involved in cellular functions related to membranes, organelles and signaling receptors. These findings may be of relevance to better understand the regulation of hepatic gluconeogenesis and the use of IDE as a potential therapeutic target for the treatment of T2D.
Read morePhthalate Metabolites and Their Relationship with Abdominal and General Obesity: Evidence from the Aragon Workers' Health Study (AWHS).
Phthalates are endocrine-disrupting chemicals that are commonly used in plastic consumer products and food packaging, with growing evidence suggesting that they have a potential role in obesity. This study aimed to investigate the association between urinary concentrations of phthalate metabolites and both general and abdominal obesity among adult males in Spain. We analysed data from 1124 male participants of the Aragon Workers' Health Study (AWHS) collected between 2011 and 2014 in Zaragoza, Spain. Eleven urinary phthalate metabolites were measured and adjusted for creatinine levels. Multivariate logistic regression models were used to evaluate associations between phthalate exposure and general and abdominal obesity, controlling for dietary and lifestyle factors. Dose-response relationships were explored using restricted cubic spline models. Higher urinary concentrations of di(2-ethylhexyl) phthalate (∑DEHP) and two of its metabolites-mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP) and mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP)-were significantly associated with general obesity. The adjusted odds ratios were: ∑DEHP [OR = 1.26; 95% CI: 1.01, 1.58], MEOHP [OR = 1.24; 95% CI: 1.00, 1.53], and MEHHP [OR = 1.26; 95% CI: 1.03, 1.55]. In contrast, mono-isobutyl phthalate (MiBP) was inversely associated with abdominal obesity [OR = 0.73; 95% CI: 0.57, 0.93]. These findings suggest a positive association between exposure to DEHP and its metabolites and general obesity. This highlights the potential importance of environmental exposures as modifiable factors in obesity prevention and supports the need for further investigation in nutritional and public health contexts.
Read moreSweet Taste Receptors’ Genetic Variability in Advanced Potential Targets of Obesity
Background: Obesity, mainly visceral obesity, causes a low-grade of chronic inflammation (meta-inflammation), associated with comorbidities such as type 2 diabetes, cardiovascular diseases, and certain cancers. Precision Nutrition aims to understand the bidirectional crosstalk between the genome and diet to improve human health. Additionally, by leveraging individual data, Precision Nutrition seeks to predict how people will respond to specific foods or dietary patterns, with the ultimate goal of providing personalized nutritional recommendations tailored to their unique needs and lifestyle factors, including poor dietary habits (e.g., high intake of sugar or saturated fatty acids, alcohol consumption, etc.) and sedentary habits, exacerbate obesity in genetically predisposed individuals. Genetic, metabolic, and environmental factors can play a crucial role during obesity. Objective: To investigate the effects of genetic variability in sweet taste receptors and their downstream signaling pathways in the gut–brain axis on anthropometry, biochemistry, and lifestyle variables. Methods: A sample of 676 volunteers (mean age of 42.22 ± 12 years, ranging from 18 to 73 years) from the database of the GENYAL platform for nutritional trials at the IMDEA Food Institute were included in this study. We present a first-in-class genetic chip, Glucosensing, designed to interrogate 25 single-nucleotide polymorphisms (SNPs) located in genes encoding sweet taste receptors and components of downstream signaling pathways. These include elements of the gut–brain axis and its associated metabolic networks, enabling a comprehensive analysis of individual variability in sweet taste perception and metabolic responses. Results: Several significant associations were found after correction for multiple comparisons, representing potential targets for personalized interventions.
Read moreGut microbial ecosystems differ across metabolic and obesity phenotypes
Abstract Obesity is a heterogeneous condition comprising a continuum of phenotypes with various metabolic and inflammatory profiles. Metabolically healthy obesity (MHO) identifies individuals with obesity but a relatively preserved metabolic state. However, the criteria defining MHO remain inconsistent, and little is known about the gut microbiome (GM) features underlying this intermediate phenotype. Here, we aim to describe microbial structures contributing to metabolic health and disease. To do so, we analyzed the GM of 959 individuals classified as metabolically healthy non-obese (MHNO), MHO, metabolically unhealthy non-obese (MUNO), and metabolically unhealthy obese (MUO), using stool shotgun metagenomics. MHO subjects display intermediate anthropometric and biochemical profiles, with a GM composition and diversity in an in-between state among MHNO and MUO individuals. Network science analyses reveal that metabolic health, rather than obesity, drives microbial connectivity: MHNO and MHO individuals harbor more robust and functionally cohesive microbial networks, whose most influential nodes are focused toward SCFA production. In contrast, MUO and MUNO communities exhibit a dysbiotic state with reduced connectivity and increased influence of low-abundance, ectopic and potentially pro-inflammatory species resulting in a damaged, unstable microbial community network. These findings suggest that metabolic disorders disrupt microbial ecology beyond compositional shifts, emphasizing the need for systems-level approaches. Our findings show differences in microbial connectivity and association patterns across metabolic and obesity phenotypes, shedding light on how distinct microbial structures may contribute to metabolic health and disease.
Read moreHydroxytyrosol Enhances Plasma Extracellular Vesicle Secretion, Modulates Their miRNAs Cargo, and Reduces LDL Oxidation in Humans: Postprandial and 1-Week Effects.
Hydroxytyrosol (HT) consumption is associated with healthy outcomes. Specifically, its ability to modulate microRNA (miRNA) expression has been described. However, whether HT influences the secretion of extracellular vesicles (EVs) and their transported miRNAs remains unknown. Here, following HT administration, we explored the potential changes in EV secretion and in their miRNA cargo during postprandial state and after 1 week of daily intake. Twelve healthy participants received, first, a single 25mg dose of HT (postprandial study) and then 25mg HT daily, for one week (sustained study). Plasma and circulating plasma-isolated EVs were analyzed for HT and derived metabolites using UPLC-qTOF-MS and miRNAs by RNA-seq. HT induced the secretion of EVs 1-h post-ingestion and a 1-week daily administration of HT increased fasting EVs and reduced circulating oxidized LDL levels. RNA-seq analysis identified 55 modulated miRNAs (30 upregulated and 25 downregulated) related to response to oxygen level and gland development, following 1-week HT supplementation. This pilot study sheds light on the effects of HT consumption on EV secretion and modulation of exosomal miRNAs in humans, which has been scarcely studied to date. Further research is warranted to elucidate the molecular mechanisms underlying the observed effects.
Read moreChanges in triglyceride-rich lipoprotein particle profiles in response to one-week on a low fat or Mediterranean diet by TCF7L2 rs7903146 genotype: a randomized crossover dietary intervention trial
BackgroundThe TCF7L2 gene is a significant genetic factor contributing to the risk of metabolic and cardiovascular diseases (CVD). We previously found that subjects with the TT genotype of TCF7L2 rs7903146 variant, who consume a low-fat diet (LF) had a higher incidence of stroke than subjects with the CC genotype. Yet this association was abolished in subjects with the TT genotype who consumed a Mediterranean-type diet (MetD). However, the mechanism by which MetD diet modulates the association between TCF7L2 and CVD risk is unclear. This study aims to validate these findings under real-world conditions and clinical practice to elucidate the biological mechanisms involved in this correlation.MethodsThirty-five participants with BMI ranging from 27 to 34 kg/m2 were recruited based on rs7903146 genotype. Of those consented to participate, 21 had the CC and 14 had the TT genotype. Participants were randomly assigned to two dietary intervention groups, ensuring an equal distribution of CC and TT carriers. Each participant followed one of two diets (LF or MetD) for one week, followed by a 10-day washout period before switching to the other diet for one week. Blood samples were collected before and after each diet for metabolomic analysis using nuclear magnetic resonance (NMR) spectroscopy. The differential effect of the diets on triglyceride-rich lipoproteins was determined based on TCF7L2 genotype.ResultsThe MetD significantly reduced triglyceride-rich lipoprotein concentrations compared to the LF diet. After consuming the LF diet, TT carriers exhibited more small VLDL particles, potentially contributing to CVD risk compared to CC carriers. However, this difference in risk was not observed with the MetD. Furthermore, the order in which the two diets were crossed affected the triglyceride-rich lipoprotein profile, with LF-MetD regimen showing a stronger effect on triglyceride-rich lipoproteins (TRL) levels than the MetD-LF regimen.ConclusionsOur findings suggest that rs7903146 TT carriers benefit more from a MetD than a LF diet in terms of their triglyceride-rich lipoprotein profile, which may reduce their risk of CVD. These results support the notion that genotype is a factor in determining the extent to which the MetD affects cardiovascular health.
Read moreIntestinal IncRNAs and circRNAs Regulated by Dietary-Lipid Stimuli.
A diet rich in lipids can lead to many deleterious conditions, which involve many regulatory molecules, such as non-coding (nc)RNAs. We aimed to analyze the effects of high dietary lipid exposure on the expression of intestinal ncRNAs (long non-coding[lncRNAs] and circular [circRNAs]). lncRNAs and circRNAs were screened, both in vivo (mice) and in vitro (human intestinal organoids). In vivo, 15 lncRNAs (9 up- and 6 downregulated) and 41 circRNAs (13 up- and 28 downregulated) were modulated 3h after a lipid challenge, while the expression of 11 lncRNAs (4 up- and 7 downregulated) was altered after 4 days of daily high-fat diet intake. In vitro, 251 up- and 387 downregulated lncRNAs, along with 19 up- and 16 downregulated circRNAs, were found 3h after the exposure to a dietary-lipid stimulus, whereas 111 up- and 86 downregulated lncRNAs were found 24h after exposure. Concord between the differently expressed ncRNAs found in both studies was scarce. Numerous differentially expressed lncRNAs and circRNAs have been found in response to dietary lipids both in mice and humans organoids. A potential association between many of these ncRNAs and lipid metabolism is suggested, but ncRNAs found differ greatly between humans and mice.
Read moreCC Genotype at TCF7L2 Diabetes Risk Locus rs7903146 Directs a Coordinated Fatty Acid Response to a Mediterranean Diet Intervention: A Randomized Controlled Trial
Introduction: Previous studies identified genetic links between the TCF7L2 C/T variant rs7903146, type 2 diabetes (T2D), and obesity. We wished to deepen our understanding of how specific diets interact with this variant to affect blood metabolites, an aspect not previously investigated. Hence, we conducted a controlled study where individuals with different genotypes followed a Mediterranean (Med) or low-fat (LF) diet for 1 week. Methods: Participants were recruited from the Boston, MA (USA) area. Anthropometric and clinical measures were taken. Genotypes at rs7903146 were ascertained, with homozygous carriers of the more common and protective CC or risk TT genotype invited to participate. Participants followed both diets (LF or Med) for 1 week with ∼10 days’ washout between diets. Blood samples taken at the beginning and end of each diet period underwent metabolomics analysis using nuclear magnetic resonance spectroscopy. We evaluated how the diet affected different metabolites based on genetic profile. Results: The cohort of 35 persons was 43% female, aged 18–70 y, with BMI between 26.4 and 33.9 kg/m2. Focusing on fatty acids (FAs) and other lipid metabolic factors (n = 23), we observed a greater number and stronger correlations among these factors in the CC genotype-Med diet group than in the other three genotype-diet combinations. An aggregate of 11 factors, each negatively correlating with delta-saturated fatty acids (SFA), showed a significant genotype-Med diet interaction on delta-SFA in CC individuals on the Med diet (p = 0.0046). A similar genotype-Med diet interaction was observed for delta-monounsaturated fatty acids (p = 0.0078). These interactions were not statistically significant at the end of the LF intervention. Conclusion: Our findings suggest that the Med diet has a stronger influence on regulating lipid factors in individuals with the CC genotype at the TCF7L2 variant rs7903146. This diet-genotype interaction may have significant implications for understanding the inter-individual variation of metabolic response on specific dietary regimens.
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