Introduction and Objective: Deoxy- and deoxymethyl-sphingolipids (m18:1 and m17:1) are two classes of sphingolipids (SLs) resulting from the condensation of palmitoyl-CoA with alanine or glycine respectively, instead of serine. Due to their structure, they evade normal catabolic routes, favoring cellular accumulation and lipotoxicity. Recent studies have highlighted the role of deoxySLs in the pathophysiology of type 2 diabetes (T2D). The aim of this study was to compare the concentrations of circulating deoxySLs in type 1 diabetes (T1D) and T2D as compared to healthy individuals. Methods: Sphingolipidomic profiles of 15 plasma samples from T1D patients, T2D patients and healthy controls (HC) (age, sex and BMI matched, n. 45 subjects) were analyzed by targeted LC/MS-MS. Statistical analysis was performed by ANOVA test. Results: Total ceramides concentrations were significantly decreased in T1D (p<0.005) and Cer 18:0/Cer 24:0 ratio, a metabolic and cardiovascular risk marker, was significantly lower in T1D compared to T2D (p<0.005). Glucosyl ceramides (HexCer) were reduced in T2D as compared to HC, while in T1D only HexCer 16:0 and 18:0 were significantly decreased as compared to HC (both p<0.05). Total contents of deoxyCers and deoxyDHCers were elevated in T2D, and significantly reduced in T1D, as compared to both HC (p<0.05) and T2D (p<0.001). DeoxymethylSLs showed a similar trend as deoxySLs, though their changes were not as marked. Sphingosine-1-phosphate levels did not differ between HC and T1D and T2D, showing no significant changes in the catabolism of canonical SLs. Conclusion: There is a differential regulation of the biosynthesis and the degradation in canonical SLs (d18:1) between T1D and T2D. Interestingly, no significant differences were found between T2D and HC. DeoxySLs were increased in T2D and decreased in T1D, as compared to controls, and could be markers of differential effects of insulin resistance, hyperglycemia and lack of endogenous insulin secretion between T1D and T2D in these processes. Disclosure L. Centofanti: None. C. Morano: None. M. Dei Cas: None. P. Zermiani: None. U. Mortola: None. M. Bignotto: None. G. Serrao: None. P. Battezzati: None. R. Paroni: None. F. Folli: None. Funding Project PNC 0000001 D3 4 Health, - CUP [B83C22006120001], The National Plan for Complementary Investments to the NRRP, Funded by the European Union – NextGenerationEU.

Circulating sphingolipids have been associated with diabetes risk and chronic complications. This study characterized the sphingolipidome in a subset of the CA.ME.LI.A. cohort to identify lipid signatures related to sex, body mass index (BMI), and fasting glucose levels. Three hundred sixty-seven subjects (217 men) were stratified into six groups based on BMI (normal weight or overweight/obese) and fasting glucose levels (normal, impaired, or diabetes). Circulating sphingolipids were measured by LC-MS/MS. The effects of BMI, glucose levels, and their interaction on the sphingolipidome were analyzed using a two-way ANOVA model. Women showed higher circulating sphingolipid levels than men, except for ganglioside GM3. Glucose levels produced relevant changes on hexosyl- and lactosylceramides, which were significantly reduced in subjects with diabetes, independently of BMI. Some ceramide and sphingomyelin species also varied only according to glucose levels. Dihydroceramide 18:0 and 24:1 were higher in overweight/obese subjects, whereas sphingomyelin 18:1 and GM3 24:0 were higher in normal-weight individuals. Gangliosides GM3 were higher in normal body weight with normal glucose levels and impaired fasting glucose as compared with overweight obese individuals of the same categories. Sphingomyelin 18:1, GM3 24:1, sphingosine, and dihydrosphingosine-1-phosphate levels were significantly regulated by both BMI and glucose. In overweight/obese individuals, sphingosine-1-phosphate and dihydrosphingosine-1P levels were reduced in impaired fasting glucose and diabetes. The circulating sphingolipidome differs in men and women, being modulated by BMI and glucose levels. These data support the concept that sphingolipids could be novel biomarkers for obesity, diabetes, and associated complications.NEW & NOTEWORTHY Sphingolipid glycosylation is an enzymatic process that does not follow the pattern of nonenzymatic hemoglobin glycosylation. Unexpectedly, hexosyl- and lactosylceramides decreased in impaired fasting glucose and diabetes, with and without obesity. On the other hand, dihydroceramides increased in overweight/obesity with prediabetes/diabetes. The circulating sphingolipidome is differentially regulated in humans according to sex, glucose, and BMI.

The primary aim of the Polymets Study is to evaluate the effect on gut microbiota composition of a polysaccharide-based complex administration combined with dietary and lifestyle interventions in a group of children and adolescents with metabolically unhealthy obesity (MUO). In this clinical trial, children and adolescents (8–14 years) with obesity (defined as body mass index > + 2 standard deviation score [BMI SDS] according to World Health Organization) and cardio-metabolic alteration (hypertriglyceridemia, hypertension, hypo-HDL cholesterol, altered glucose metabolism) were enrolled. Participants received from baseline (T0) to 4 months (T1) combined polysaccharide-based complex administration (5 g/day mixture of soluble and insoluble fibres) and Mediterranean diet intervention; from 4 to 8 months (T2) they underwent dietary intervention alone. At T0, T1 and T2 gut microbiota analysis, body composition assessment, blood tests and Mediterranean diet adherence (KIDMED score) were assessed. Overall, 31 children were enrolled (10.9 ± 1.6 years, F/M 8/23). BMI SDS significantly decreased at each timepoint (p < 0.001), whilst fat mass

Background: Psilocybin and its active metabolite psilocin are widely studied for psychiatric disorders due their effects mediated by serotoninergic activation at 5-HT2A receptor. Beyond central actions, emerging evidence suggests potential metabolic and hepatoprotective effects. This study investigated the molecular mechanisms and efficacy of psilocybin in in vitro and in vivo models of MASH.Methods: Psilocin’s activity at 5-HT2 receptors isoforms was characterized using a FLIPR calcium-mobilization assay. Functional studies included bodipy lipid droplet staining in HepG2 cells with a loss of function 5-HT2A receptor mutation and pharmacological inhibition of 5-HT2B receptor. Immunocytochemistry and rtPCR analyses in LX-2 stellate cells were performed. In vivo, non-psychedelic doses of psilocybin (0.05 mg/kg, orally) were tested in mice fed the Novel Gubra Amylin NASH (GAN) diet for 17 weeks up to week 22 of diet, when early signs of inflammation and fibrosis were expected to arise. Histological (Hematoxylin and Eosin, Sirius Red) and molecular markers of steatosis and fibrogenesis were evaluated.Results: Besides its known partial agonism at 5-HT2A and 5-HT2C receptors, psilocin exhibited antagonism at 5-HT2B receptor. Lipid-lowering effects were maintained in 5-HT2A-mutant HepG2, while 5-HT2B inhibition fully reproduced psilocin’s activity, identifying this receptor as a key mediator. In LX-2 cells, 5-HT2B antagonism reduced COL1A1 expression to the same extent as psilocin, while at transcript level, psilocin reduced ACTA2 and MMP2 gene expression. In vivo, psilocybin attenuated micro- and macrovesicular steatosis in GAN-fed mice and reduced ACTA2 expression, suggesting early antifibrotic activity.Conclusions: These findings highlight psilocin as a dual-action modulator of hepatic lipid accumulation and fibrogenesis via 5-HT2B antagonism. By avoiding risks of 5-HT2B activation, psilocybin may also hold promise in preventing the progression of MASLD toward MASH through a possible antifibrotic activity, representing a valuable therapeutic candidate offering an orally available, well-tolerated therapy effective at very low, non-psychedelic doses.

Background: Esmethadone is a novel N-methyl-D-aspartate receptor (NMDAR) uncompetitive antagonist in development as adjunctive treatment for major depressive disorder (MDD). Methods: This 12-month, open-label study evaluated the safety and efficacy of esmethadone in patients with MDD meeting DSM-5 criteria who completed 1 of 3 double-blind studies (rollover) and in patients with MDD and no prior participation in esmethadone studies (de novo). Safety was assessed from adverse events, laboratory parameters, vital signs, electrocardiogram, and the Columbia-Suicide Severity Rating Scale. Efficacy assessments used measures of depression, anxiety, sleep, sexual function, cognitive function, and quality of life. The safety population comprised patients who received at least 1 dose of study drug, and the full analysis set (FAS) comprised patients who had at least 1 postbaseline efficacy assessment. Results: Safety population included 624 patients; FAS included 586 patients (384 rollover and 202 de novo); mean age was 42.9 (13.6) years, and mean baseline Montgomery-Asberg Depression Rating Scale (MADRS10) was 34.5 (4.8). Most common treatment-related treatment emergent adverse events were headache (4.6%), nausea (4.2%), and dizziness (2.6%). There were no signals of meaningful neurological, cardiovascular, metabolic, or sexual adverse events and no case of suicide or suicidal attempt. For the FAS, mean (SD) change from baseline for MADRS10 at 3, 6, 9, and 12 months was -20.1 (10.7), -21.0 (10.8), -21.6 (10.7), and -21.6 (10.4). For the de novo population, mean (SD) was -19.9 (10.0), -19.9 (10.4), -20.1 (10.2), and -22.5 (9.7). Consistent improvements occurred with other tested efficacy measures. Conclusions: Long-term treatment with esmethadone was safe and well tolerated. The antidepressant efficacy of esmethadone was sustained over 12 months. Trial Registration: ClinicalTrials.gov identifier: NCT04855760.

The therapeutic potential of low, non-psychedelic doses of psilocybin, a fungal tryptamine alkaloid, was investigated in metabolic disorders including obesity, type 2 diabetes mellitus (T2DM), and liver steatosis. Mice fed a high-fat/high-fructose diet received chronic treatment with psilocybin (0.05mg/kg) for 12 weeks. Body weight, liver histology, insulin sensitivity, and skeletal muscle function were assessed, and hepatic and muscle tissues underwent transcriptomic and lipidomic analyses.The role of three serotonin receptors (5-HT2A, 5-HT2B, and 5-HT2C) in psilocybin-induced metabolic effects was examined in human cell lines using pharmacological and CRISPR/Cas9-based genetic approaches.Low-dose psilocybin reduced body-weight gain, liver steatosis, hyperglycaemia, and insulin resistance without eliciting central nervous system effects. Multi-omics analyses revealed near-complete normalization of disrupted hepatic lipid and carbohydrate metabolism pathways. Psilocybin also improved muscle strength and function, potentially through restoration of leptin sensitivity. Mechanistic studies demonstrated that these metabolic benefits were independent of the canonical psychedelic target 5-HT2A and instead resulted from antagonism of the serotonin 5-HT2B receptor in the liver.Overall, chronic low-dose psilocybin exerts broad metabolic benefits via a hepatic 5-HT2B-dependent mechanism, distinct from its psychedelic effects, supporting its potential as a novel therapeutic strategy for liver steatosis, obesity, T2DM, and sarcopenia.

Background: Antidepressant tolerance/ tachyphylaxis (AT) is defined as initial response (≥ 50% improvement) to antidepressant treatment followed by relapse while on the same adequate dose. The impact of AT as prognostic indicator for response to subsequent antidepressant treatment is unknown. Objective: To test the efficacy of esmethadone (REL-1017) in a subgroup of patients with major depressive disorder (MDD) and AT. Methods: A phase 3, double-blind, randomized, placebo-controlled trial of esmethadone was conducted in adult outpatients with MDD. Prior to randomization, AT was independently assessed by clinicians from the Massachusetts General Hospital Clinical Trials Network and Institute using the MGH Antidepressant Treatment Response Questionnaire. Data for the primary efficacy end point were analyzed using mean difference in Montgomery-Åsberg Depression Rating Scale (MADRS) total score from baseline to primary end point (Day 28) in the AT subgroup from the intent to treat (ITT) population, the per-protocol (PP) population, and in patients with severe depression (baseline MADRS ≥35). Results: Among 227 ITT patients, 87 experienced AT. For this subgroup, there was a nominally statistically significant mean difference of 5.4 (P=.023, Cohen effect size 0.53) for esmethadone vs placebo in MADRS total score change from baseline to primary end point (Day 28). Additionally, there was a nominally statistically significant difference in response rate (P=.0004). Consistent results were seen in the PP population with AT and in the severely depressed subgroup of patients with AT. Conclusions: These post hoc analyses, based on data collected independently pre-randomization, suggest that esmethadone may be an effective adjunctive treatment for patients with AT. These results need to be confirmed in larger prospective clinical trials.

Mechanisms by which mucosal regeneration is abrogated in inflammatory bowel disease (IBD) are still under investigation, and a role for an intestinal stem cell (ISC) defect is now emerging. Herein, we report an abnormal ISC death that occurs in Crohn's disease, which exacerbates colitis, limits ISC-dependent mucosal repair, and is controlled through the death factor Transmembrane protein 219 (TMEM219). Large alterations in TMEM219 expression were observed in patients with Crohn's disease, particularly in those with active disease and/or those who were nonresponders to conventional therapy, confirming that TMEM219 signaling is abnormally activated and leads to failure of the mucosal regenerative response. Mechanistic studies revealed a proapoptotic TMEM219-mediated molecular signature in Crohn's disease, which associates with Caspase-8 activation and ISC death. Pharmacological blockade of the IGFBP3/TMEM219 binding/signal with the recombinant protein ecto-TMEM219 restored the self-renewal abilities of miniguts generated from patients with Crohn's disease in vitro and ameliorated DSS-induced and T cell-mediated colitis in vivo, ultimately leading to mucosal healing. Genetic tissue-specific deletion of TMEM219 in ISCs in newly generated TMEM219fl/flLGR5cre mice revived their mucosal regenerative abilities both in vitro and in vivo. Our findings demonstrate that a TMEM219-dependent ISC death exacerbates colitis and that TMEM219 blockade reestablishes intestinal self-renewal properties in IBD.

Studies on morbid obese diabetic and non-diabetic patients’ social characteristics and habits, in candidates for bariatric surgery (BS) are few. To gain further insights, we investigated 799 morbid obese diabetic (n = 111) and non-diabetic patients (n = 688). Family history of cardiometabolic diseases, personal history, education and occupation, comorbidities, daily habits, previous dietetic treatment, reasons and pathway to BS were investigated. Team members involved and examinations performed were also analyzed. Family histories of obesity, diabetes and hypertension significantly associated with each other, and clinically overt diseases were also associated with family histories of the same disease, as diabetes and hypertension, and were more frequent in diabetic as compared to non-diabetic (p > 0.05, p < 0.0001 and p < 0.05). Females significantly differed from males for lower body mass index (BMI) (mean 41.2 vs 42.8 kg/m2), and a lower alcohol intake (p < 0.05 to p < 0.001). Knowledge about BS and reasons for BS varied according to age. BS was mostly requested for medical reasons (80.1

To reduce mortality, thigh glycemic control is recommended in critically ill patients due to their extreme glycemic variability. Continuous glucose monitoring (CGM) devices allows frequent determination of blood glucose levels; however, conflicting results have been reported from studies assessing their accuracy in critically ill patients. Aim of this study was to assess the repeatability and the analytical and clinical accuracy of FreeStyle Libre 2 (FSL-)CGM. Prospective single-center observational study enrolling 40 critically ill patients. For four consecutive days, we measured three consecutive interstitial FSL-CGM-derived glucose levels, along with one arterial and venous blood gas analysis and a capillary-derived blood glucose level, obtaining a total of 480 FSL-CGM-derived glucose measurements and 160 measurements from arterial and venous blood gas analysis and from capillary glucose. The mean blood glucose levels in the three daily timepoints from FSL-CGM were 130 ± 35, 131 ± 35 and 131 ± 35 mg/dL (p = 0.660). The Bland-Altman analysis comparing arterial BGA- and FSL-CGM-derived blood glucose levels had a bias of 10.3 mg/dL with limits of agreement from − 27.2 to 47.7. The mean absolute relative difference (MARD) between FSL-CGM and arterial blood gas analysis was 12 ± 10