Serum identification of at-risk MASH: The metabolomics-advanced steatohepatitis fibrosis score (MASEF).

BACKGROUND: Early identification of those with NAFLD activity score ≥ 4 and significant fibrosis (≥F2) or at-risk metabolic dysfunction-associated steatohepatitis (MASH) is a priority as these patients are at increased risk for disease progression and may benefit from therapies. We developed and validated a highly specific metabolomics-driven score to identify at-risk MASH. METHODS: We included derivation (n = 790) and validation (n = 565) cohorts from international tertiary centers. Patients underwent laboratory assessment and liver biopsy for metabolic dysfunction-associated steatotic liver disease. Based on 12 lipids, body mass index, aspartate aminotransferase, and alanine aminotransferase, the MASEF score was developed to identify at-risk MASH and compared to the FibroScan-AST (FAST) score. We further compared the performance of a FIB-4 + MASEF algorithm to that of FIB-4 + liver stiffness measurements (LSM) by vibration-controlled transient elastography (VCTE). RESULTS: The diagnostic performance of the MASEF score showed an area under the receiver-operating characteristic curve, sensitivity, specificity, and positive and negative predictive values of 0.76 (95% CI 0.72-0.79), 0.69, 0.74, 0.53, and 0.85 in the derivation cohort, and 0.79 (95% CI 0.75-0.83), 0.78, 0.65, 0.48, and 0.88 in the validation cohort, while FibroScan-AST performance in the validation cohort was 0.74 (95% CI 0.68-0.79; p = 0.064), 0.58, 0.79, 0.67, and 0.73, respectively. FIB-4+MASEF showed similar overall performance compared with FIB-4 + LSM by VCTE ( p = 0.69) to identify at-risk MASH. CONCLUSION: MASEF is a promising diagnostic tool for the assessment of at-risk MASH. It could be used alternatively to LSM by VCTE in the algorithm that is currently recommended by several guidance publications.

Metabolic subtypes of patients with NAFLD exhibit distinctive cardiovascular risk profiles.

BACKGROUND AND AIMS: We previously identified subsets of patients with NAFLD with different metabolic phenotypes. Here we align metabolomic signatures with cardiovascular disease (CVD) and genetic risk factors. APPROACH AND RESULTS: We analyzed serum metabolome from 1154 individuals with biopsy-proven NAFLD, and from four mouse models of NAFLD with impaired VLDL-triglyceride (TG) secretion, and one with normal VLDL-TG secretion. We identified three metabolic subtypes: A (47%), B (27%), and C (26%). Subtype A phenocopied the metabolome of mice with impaired VLDL-TG secretion; subtype C phenocopied the metabolome of mice with normal VLDL-TG; and subtype B showed an intermediate signature. The percent of patients with NASH and fibrosis was comparable among subtypes, although subtypes B and C exhibited higher liver enzymes. Serum VLDL-TG levels and secretion rate were lower among subtype A compared with subtypes B and C. Subtype A VLDL-TG and VLDL-apolipoprotein B concentrations were independent of steatosis, whereas subtypes B and C showed an association with these parameters. Serum TG, cholesterol, VLDL, small dense LDL5,6 , and remnant lipoprotein cholesterol were lower among subtype A compared with subtypes B and C. The 10-year high risk of CVD, measured with the Framingham risk score, and the frequency of patatin-like phospholipase domain-containing protein 3 NAFLD risk allele were lower in subtype A. CONCLUSIONS: Metabolomic signatures identify three NAFLD subgroups, independent of histological disease severity. These signatures align with known CVD and genetic risk factors, with subtype A exhibiting a lower CVD risk profile. This may account for the variation in hepatic versus cardiovascular outcomes, offering clinically relevant risk stratification.

Metabolomic Identification of Subtypes of Nonalcoholic Steatohepatitis.

BACKGROUND & AIMS: Nonalcoholic fatty liver disease (NAFLD) is a consequence of defects in diverse metabolic pathways that involve hepatic accumulation of triglycerides. Features of these aberrations might determine whether NAFLD progresses to nonalcoholic steatohepatitis (NASH). We investigated whether the diverse defects observed in patients with NAFLD are caused by different NAFLD subtypes with specific serum metabolomic profiles, and whether these can distinguish patients with NASH from patients with simple steatosis. METHODS: We collected liver and serum from methionine adenosyltransferase 1a knockout (MAT1A-KO) mice, which have chronically low levels of hepatic S-adenosylmethionine (SAMe) and spontaneously develop steatohepatitis, as well as C57Bl/6 mice (controls); the metabolomes of all samples were determined. We also analyzed serum metabolomes of 535 patients with biopsy-proven NAFLD (353 with simple steatosis and 182 with NASH) and compared them with serum metabolomes of mice. MAT1A-KO mice were also given SAMe (30 mg/kg/day for 8 weeks); liver samples were collected and analyzed histologically for steatohepatitis. RESULTS: Livers of MAT1A-KO mice were characterized by high levels of triglycerides, diglycerides, fatty acids, ceramides, and oxidized fatty acids, as well as low levels of SAMe and downstream metabolites. There was a correlation between liver and serum metabolomes. We identified a serum metabolomic signature associated with MAT1A-KO mice that also was present in 49% of the patients; based on this signature, we identified 2 NAFLD subtypes. We identified specific panels of markers that could distinguish patients with NASH from patients with simple steatosis for each subtype of NAFLD. Administration of SAMe reduced features of steatohepatitis in MAT1A-KO mice. CONCLUSIONS: In an analysis of serum metabolomes of patients with NAFLD and MAT1A-KO mice with steatohepatitis, we identified 2 major subtypes of NAFLD and markers that differentiate steatosis from NASH in each subtype. These might be used to monitor disease progression and identify therapeutic targets for patients.

Sterile inflammation in acetaminophen-induced liver injury is mediated by Cot/tpl2.

Cot/tpl2 (MAP3K8) activates MKK1/2-Erk1/2 following stimulation of the Toll-like/IL-1 receptor superfamily. Here, we investigated the role of Cot/tpl2 in sterile inflammation and drug-induced liver toxicity. Cot/tpl2 KO mice exhibited reduced hepatic injury after acetaminophen challenge, as evidenced by decreased serum levels of both alanine and aspartate aminotransferases, decreased hepatic necrosis, and increased survival relative to Wt mice. Serum levels of both alanine and aspartate aminotransferases were also lower after intraperitoneal injection of acetaminophen in mice expressing an inactive form of Cot/tpl2 compared with Wt mice, suggesting that Cot/tpl2 activity contributes to acetaminophen-induced liver injury. Furthermore, Cot/tpl2 deficiency reduced neutrophil and macrophage infiltration in the liver of mice treated with acetaminophen, as well as their hepatic and systemic levels of IL-1α. Intraperitoneal injection of damage-associated molecular patterns from necrotic hepatocytes also impaired the recruitment of leukocytes and decreased the levels of several cytokines in the peritoneal cavity in Cot/tpl2 KO mice compared with Wt counterparts. Moreover, similar activation profiles of intracellular pathways were observed in Wt macrophages stimulated with Wt or Cot/tpl2 KO damage-associated molecular patterns. However, upon stimulation with damage-associated molecular patterns, the activation of Erk1/2 and JNK was deficient in Cot/tpl2 KO macrophages compared with their Wt counterparts; an effect accompanied by weaker release of several cytokines, including IL-1α, an important component in the development of sterile inflammation. Taken together, these findings indicate that Cot/tpl2 contributes to acetaminophen-induced liver injury, providing some insight into the underlying molecular mechanisms.

Solute carrier family 2 member 1 is involved in the development of nonalcoholic fatty liver disease.

UNLABELLED: Susceptibility to develop nonalcoholic fatty liver disease (NAFLD) has genetic bases, but the associated variants are uncertain. The aim of the present study was to identify genetic variants that could help to prognose and further understand the genetics and development of NAFLD. Allele frequencies of 3,072 single-nucleotide polymorphisms (SNPs) in 92 genes were characterized in 69 NAFLD patients and 217 healthy individuals. The markers that showed significant allele-frequency differences in the pilot groups were subsequently studied in 451 NAFLD patients and 304 healthy controls. Besides this, 4,414 type 2 diabetes mellitus (T2DM) cases and 4,567 controls were genotyped. Liver expression of the associated gene was measured and the effect of its potential role was studied by silencing the gene in vitro. Whole genome expression, oxidative stress (OS), and the consequences of oleic acid (OA)-enriched medium on lipid accumulation in siSLC2A1-THLE2 cells were studied by gene-expression analysis, dihydroethidium staining, BODIPY, and quantification of intracellular triglyceride content, respectively. Several SNPs of SLC2A1 (solute carrier family 2 [facilitated glucose transporter] member 1) showed association with NAFLD, but not with T2DM, being the haplotype containing the minor allele of SLC2A1 sequence related to the susceptibility to develop NAFLD. Gene-expression analysis demonstrated a significant down-regulation of SLC2A1 in NAFLD livers. Enrichment functional analyses of transcriptome profiles drove us to demonstrate that in vitro silencing of SLC2A1 induces an increased OS activity and a higher lipid accumulation under OA treatment. CONCLUSIONS: Genetic variants of SLC2A1 are associated with NAFLD, and in vitro down-regulation of this gene promotes lipid accumulation. Moreover, the oxidative response detected in siSLC2A1-THLE2 cells corroborated the antioxidant properties previously related to this gene and linked the most representative clinical characteristics of NAFLD patients: oxidative injury and increased lipid storage.

[Use of social networks as a source of information on health and digital health literacy in the Spanish general population]. / Uso de redes sociales como fuente de información sobre salud y alfabetización digital en salud en población general española.

OBJECTIVE: Social media allows individuals to access a vast amount of health-related information immediately and anonymously, a fact that is turning these platforms into one of the primary sources of reference in this area, especially for younger generations. Given this reality, the objective of determining the impact of social media on digital health literacy in the general Spanish population was proposed. METHODS: A cross-sectional descriptive study was carried out in 2023. Using a non-probabilistic sampling, the population residing in Spain, over eighteen years old, and users of social networks were included, obtaining a sample of 1,307 participants. An adaptation of the validated eHEALS questionnaire on digital health literacy was used. This questionnaire, created in Microsoft Forms, was disseminated through an anonymous link via the research team's social networks and collaborators. A descriptive and inferential statistical analysis was performed using SPSS 22.0, assuming a significance level with a value of p<0.05. RESULTS: All participants affirmed having consumed health information through social networks, but 72.1% stated they had actively used these platforms to search for this health information. Regarding digital health literacy, a median score of 24 out of 40 points was obtained on the questionnaire, being significantly higher among those who claimed to use social networks as a source of health information (p=0.0001). CONCLUSIONS: Actively employing social media as a source of health information is associated with a higher level of digital health literacy.

OBJECTIVE: Las redes sociales permiten a las personas acceder de manera inmediata y anónima a una cantidad ingente de información sobre aspectos de salud, hecho que está provocando que se estén convirtiendo en una de las fuentes de referencia en este ámbito, sobre todo para las generaciones más jóvenes. Atendiendo a esta realidad se planteó el objetivo de determinar el impacto de las redes sociales en la alfabetización digital en salud en la población general española. METHODS: Se realizó un estudio descriptivo transversal en el año 2023. Mediante un muestreo no probabilístico, se incluyó población residente en España, mayor de dieciocho años y usuaria de redes sociales, obteniendo una muestra de 1.307 participantes. Se utilizó una adaptación del cuestionario validado eHEALS sobre alfabetización digital en salud. Dicho cuestionario, elaborado en Microsoft Forms, fue difundido mediante un enlace anónimo a través de las redes sociales del equipo investigador y colaboradores. Se realizó un análisis estadístico descriptivo e inferencial mediante SPSS 22.0, asumiendo un nivel de significación con un valor de p<0,05. RESULTS: La totalidad de los participantes afirmaron haber consumido información sobre salud a través de redes sociales, pero fue el 72,1% el que afirmó haber usado estas plataformas activamente para buscar esta información sobre salud. Con respecto a la alfabetización digital en salud, se obtuvo una puntuación mediana en el cuestionario de 24 sobre 40 puntos, siendo significativamente mayor entre los que afirmaron usar las redes sociales como fuente de información sobre salud (p=0,0001). CONCLUSIONS: Emplear de manera activa las redes sociales como fuente de información sobre salud parece tener relación con un mayor nivel de alfabetización digital en salud.

[Evaluation of the sentinel lymph node in T1-T2 papillary thyroid cancer: a preliminary study]. / Valoración del ganglio centinela en el cáncer papilar de tiroides T1-T2. Estudio preliminar.

OBJECTIVE: Sentinel lymph node biopsy in differentiated thyroid cancer may benefit patients with no clinically affected lymph nodes and can avoid a prophylactic or staging lymphadenectomy. METHODS: A prospective study was conducted on 23 consecutive patients with papillary thyroid carcinoma with no clinical or radiological suspicion of lymph involvement. After injecting methylene blue around the tumour during the biopsy of the identified sentinel lymph node, a total thyroidectomy and a via-b ipsilateral lymphadenectomy was performed for the later study with cytokeratin. If the sentinel lymph node was positive, a modified ipsilateral radical lymphadenectomy was perfumed (groups ii to v). RESULTS: The sentinel lymph node was clearly identified in 21 of the 23 patients (91.3%). Seven (33%) of the 21 lymph nodes identified were positive in the intra-operative study, of which 3 (42.8%) demonstrated involvement with the lateral compartment. All together, 9 patients (39.1%) showed lymph node involvement group vi, with two more patients being identified with micro-metastases in the later study. Biopsy of the sentinel lymph node had a sensitivity of 87.5%, a specificity of 100%, a positive predictive value of 100% and a negative predictive value of 93.7%, with 7.1% false negatives. Five patients (21.7%) had transient hypocalcaemia. CONCLUSIONS: The identification of the sentinel lymph node in patients with T1-T2 tumours with no suspicion of lymph node involvement helps in the selection of patients who should be treated with selective lymphadenectomies.

Involvement of Cot activity in the proliferation of ALCL lymphoma cells.

Anaplastic large-cell lymphoma (ALCL) cells overexpress CD30 on their cell surface, show increased levels of activated Erk1/2 and of JunB; participating JunB in the proliferative capacity of these lymphomas. Here, we show that ALCL lymphoma cells also present high expression levels of the proto-oncogenic Cot (MAP3K8). Using pharmacological drugs as well as the RNA interference technique we show that Cot protein is responsible for the constitutive Erk1/2 activation in the ALCL lymphoma cells, SUDHL-1. Besides, inhibition of Cot activity reduces the number of cell divisions which is achieved, at least in part, by the control that Cot exercises on the activation state of p70 S6K and on the expression levels of JunB. Since Cot represents an alternative mode, independently of RAF, to activate Erk1/2, all these data strongly suggest that molecular targeting of Cot may be a potential new specific strategy for ALCL lymphomas therapy, without the fully disturbance of the Erk1/2 function.

Liquid chromatography-mass spectrometry-based parallel metabolic profiling of human and mouse model serum reveals putative biomarkers associated with the progression of nonalcoholic fatty liver disease.

Nonalcoholic fatty liver disease (NAFLD) is the most common form of chronic liver disease in most western countries. Current NAFLD diagnosis methods (e.g., liver biopsy analysis or imaging techniques) are poorly suited as tests for such a prevalent condition, from both a clinical and financial point of view. The present work aims to demonstrate the potential utility of serum metabolic profiling in defining phenotypic biomarkers that could be useful in NAFLD management. A parallel animal model/human NAFLD exploratory metabolomics approach was employed, using ultra performance liquid chromatography-mass spectrometry (UPLC-MS) to analyze 42 serum samples collected from nondiabetic, morbidly obese, biopsy-proven NAFLD patients, and 17 animals belonging to the glycine N-methyltransferase knockout (GNMT-KO) NAFLD mouse model. Multivariate statistical analysis of the data revealed a series of common biomarkers that were significantly altered in the NAFLD (GNMT-KO) subjects in comparison to their normal liver counterparts (WT). Many of the compounds observed could be associated with biochemical perturbations associated with liver dysfunction (e.g., reduced Creatine) and inflammation (e.g., eicosanoid signaling). This differential metabolic phenotyping approach may have a future role as a supplement for clinical decision making in NAFLD and in the adaption to more individualized treatment protocols.

Activation of bombesin receptor Subtype-3 by [D-Tyr6,ß-Ala11,Phe13,Nle14]bombesin6-14 increased glucose uptake and lipogenesis in human and rat adipocytes.

BRS-3 has an important role in glucose homeostasis. Its expression was reduced in skeletal muscle from obese and/or diabetic patients, and BRS-3 KO-mice developed obesity. In this work, focused on rat/human adipose tissue, BRS-3 gene-expression was lower than normal-levels in hyperlipidemic, type-2-diabetic (T2D), and type-1-diabetic rats and also in obese (OB) and T2D patients. Moreover, BRS-3 protein levels were decreased in diabetic rat and in obese and diabetic human fat pieces; but neither mutation nor even polymorphism in the BRS-3-gene was found in OB or T2D patients. Interestingly, in rat and human adipocytes, without metabolic alterations, [D-Tyr6,ß-Ala11,Phe13,Nle14]bombesin6-14 -BRS-3-agonist-, as insulin, enhanced BRS-3 gene/protein expression, increased, PKB, p70s6K, MAPKs and p90RSK1 phosphorylation-levels, and induced a concentration-related stimulation of glucose transport, GLUT-4 membrane translocation and lipogenesis, exclusively mediated by BRS-3, and abolished by wortmannin, PD98059 or rapamacyn. These results confirm that BRS-3 and/or its agonist are a potential therapeutic tool for obesity/diabetes.

Metabolomic-based noninvasive serum test to diagnose nonalcoholic steatohepatitis: Results from discovery and validation cohorts.

Nonalcoholic fatty liver disease (NAFLD) is the most common type of chronic liver disease worldwide and includes a broad spectrum of histologic phenotypes, ranging from simple hepatic steatosis or nonalcoholic fatty liver (NAFL) to nonalcoholic steatohepatitis (NASH). While liver biopsy is the reference gold standard for NAFLD diagnosis and staging, it has limitations due to its sampling variability, invasive nature, and high cost. Thus, there is a need for noninvasive biomarkers that are robust, reliable, and cost effective. In this study, we measured 540 lipids and amino acids in serum samples from biopsy-proven subjects with normal liver (NL), NAFL, and NASH. Using logistic regression analysis, we identified two panels of triglycerides that could first discriminate between NAFLD and NL and second between NASH and NAFL. These noninvasive tests were compared to blinded histology as a reference standard. We performed these tests in an original cohort of 467 patients with NAFLD (90 NL, 246 NAFL, and 131 NASH) that was subsequently validated in a separate cohort of 192 patients (7 NL, 109 NAFL, 76 NASH). The diagnostic performances of the validated tests showed an area under the receiver operating characteristic curve, sensitivity, and specificity of 0.88 ± 0.05, 0.94, and 0.57, respectively, for the discrimination between NAFLD and NL and 0.79 ± 0.04, 0.70, and 0.81, respectively, for the discrimination between NASH and NAFL. When the analysis was performed excluding patients with glucose levels >136 mg/dL, the area under the receiver operating characteristic curve for the discrimination between NASH and NAFL increased to 0.81 ± 0.04 with sensitivity and specificity of 0.73 and 0.80, respectively. Conclusion: The assessed noninvasive lipidomic serum tests distinguish between NAFLD and NL and between NASH and NAFL with high accuracy. (Hepatology Communications 2018;2:807-820).

The action of GLP-1 and exendins upon glucose transport in normal human adipocytes, and on kinase activity as compared to morbidly obese patients.

A role of GLP-1 (glucagon-like peptide-1) in the recovery of the metabolic conditions of morbidly obese patients after bariatric surgery has been proposed. Exendin 4 (Ex-4) and exendin 9 (Ex-9) both have GLP-1-like effects upon glucose metabolism in human myocytes. We investigated in normal human adipocytes the effect of GLP-1, Ex-4 and Ex-9, compared with insulin upon the activity of PI3K, PKB, MAPKs and p70s6 kinases, and the participation of these enzymes in their action upon 2-deoxy-D-glucose transport by using potential inhibitors. The study was extended to morbidly obese patients. In normal subjects, GLP-1, Ex-4 and insulin, but not Ex-9, increased glucose uptake. In addition, GLP-1 and Ex-4 stimulated PI3K and MAPKs, similar to insulin, but not PKB. Ex-9 only enhanced PI3K, while none affected p70s6k. Inhibition of both PI3K and MAPKs blocked the stimulatory action of GLP-1, Ex-4 and insulin upon glucose transport. In obese patients, basal PI3K, PKB and MAPK activity was, as a rule, lower than that in normal subjects, while cells maintained their normal incremental response to GLP-1, Ex-4 or insulin; Ex-9 induced a clear stimulation of p42 MAPK. In summary, in normal human adipocytes, GLP-1 and Ex-4 have a protein kinase-dependent increasing effect upon glucose transport, which is impaired in obese patients. The participation of GLP-1 in the normalization of the metabolic conditions of the obese may occur through its effects on lipid metabolism or through effects upon glucose transport and/or metabolism in the liver and muscle, which in human obesity remain to be investigated.

Map3k8 controls granulocyte colony-stimulating factor production and neutrophil precursor proliferation in lipopolysaccharide-induced emergency granulopoiesis.

Map3k8 has been proposed as a useful target for the treatment of inflammatory diseases. We show here that during lipopolysaccharide-induced emergency granulopoiesis, Map3k8 deficiency strongly impairs the increase in circulating mature (Ly6GhighCD11b+) and immature (Ly6GlowCD11b+) neutrophils. After chimaeric bone marrow (BM) transplantation into recipient Map3k8-/- mice, lipopolysaccharide treatment did not increase circulating Ly6GhighCD11b+ cells and strongly decreased circulating Ly6GlowCD11b+ cells. Lipopolysaccharide-treated Map3k8-/- mice showed decreased production of granulocyte colony-stimulating factor (G-CSF), a key factor in neutrophil expansion, and a Map3k8 inhibitor blocked lipopolysaccharide-mediated G-CSF expression in endothelial cell lines. Ly6GlowCD11b+ BM cells from lipopolysaccharide-treated Map3k8-/- mice displayed impaired expression of CCAAT-enhancer-binding protein ß, which depends on G-CSF for expression and is crucial for cell cycle acceleration in this life-threatening condition. Accordingly, lipopolysaccharide-treated Map3k8-/- mice showed decreased Ly6GlowCD11b+ BM cell proliferation, as evidenced by a decrease in the percentage of the most immature precursors, which have the highest proliferation capacity among this cell population. Thus, Map3k8 expression by non-haematopoietic tissue is required for lipopolysaccharide-induced emergency granulopoiesis. The novel observation that inhibition of Map3k8 activity decreases neutrophilia during life-threatening systemic infection suggests a possible risk in the proposed use of Map3k8 blockade as an anti-inflammatory therapy.

Effect of GLP-1 on D-glucose transport, lipolysis and lipogenesis in adipocytes of obese subjects.

GLP-1 has anorectic properties and regulates fuel homeostasis through both its insulinotropic and insulinotrophic actions and effects in extrapancreatic tissue. This study is aimed at characterizing the response to GLP-1 of adipocytes from obese patients, in terms of D-glucose transport and lipid metabolism, in comparison with data from normal subjects. Adipocytes were obtained by enzymatic digestion from the abdominal fat tissue of 25 morbidly obese patients and 8 normal subjects undergoing bariatric or inguinal hernia surgery, respectively. Basal GLUT4 expression, D-glucose transport, glycerol release and lipogenesis were measured in cells treated, when required, with 10(-12)-10(-9) M GLP-1, insulin, glucagon and the GLP-1 structurally related peptides, exendin-4 and exendin-9. In obese patients, versus normal subjects, a trend towards lower values was found in GLUT4 protein or mRNA, although the differences were not statistically significant; insulin-stimulated glucose uptake was higher and cells did not respond to GLP-1, while both exendins (10(-10) and 10(-9) M) exerted an inhibitory action; basal lipolysis was higher and so was the effect of GLP-1 and glucagon, whereas insulin abolished the lipolytic action of all peptides; both basal lipogenesis and the response to insulin were higher while GLP-1 and exendin-4 were ineffective. These results document the analogies and dissimilarities between the response to GLP-1, exendin-4 and exendin-9, as well as to insulin and glucagon, relative to glucose transport and lipid metabolism of fat tissue from obese patients versus normal subjects, the reduced lipogenic effect and enhanced lipolytic action of GLP-1 being, perhaps, adequate for its therapeutic use in obesity.

Changes in glucagon-like peptide-1 (GLP-1) secretion after biliopancreatic diversion or vertical banded gastroplasty in obese subjects.

BACKGROUND: Bariatric operations promote weight loss and improve glucose homeostasis. Glucagon-like peptide-1 (GLP-1) is considered as a possible mediator of the antidiabetic effects of such operations. METHODS: The present study aimed to gain information on the time course for changes in glucose tolerance, as well as insulin, glucagon and GLP-1 secretion, during an oral glucose tolerance test (OGTT), in 31 obese patients examined 1, 3 and 6 months after Larrad's biliopancreatic diversion (BPD) or 6 months after vertical banded gastroplasty (VBG). RESULTS: A time-related progressive decrease in body weight coincided with lowering of plasma triglycerides, decrease of basal plasma glucose and its incremental area during OGTT, and reduction of basal plasma insulin together with an increase of its incremental area. The time-related decrease of plasma glucagon during OGTT was comparable before and after surgery. Both the basal plasma GLP-1 concentration and its incremental area during the OGTT increased strikingly after surgery, a steady-state situation being reached 3 months after surgery. The most striking differences between the somewhat older and less glucose-tolerant subjects of VBG compared to BPD after surgery, consisted in a decrease in cholesterol and LDL only observed in BPD and a much more pronounced increase in basal and incremental plasma GLP-1 in BPD. GLP-1, like glucagon, increased lipolysis, but failed to duplicate the lipogenetic action of insulin in isolated adipocytes obtained at the time of surgery. CONCLUSION: These findings support the postulated role of GLP-1, secreted by the hindgut, as a key mediator of the antidiabetic effects of bariatric operations.

GLP-1 signalling and effects on glucose metabolism in myocytes from type 2 diabetic patients.

Changes in the activity of glycogen synthase a and related kinases (phosphatidylinositol-3-kinase, protein kinase B, p44/42 MAP kinases and p70s6 kinase) evoked by GLP-1 in human myocytes from normal subjects were recently implied in the effect of this hormone upon D-glucose transport and glycogen synthesis in the same cells. The major aims of the present study were i) to investigate the possible extension of this knowledge to myocytes obtained from type 2 diabetic patients, ii) to compare in these patients the response to GLP-1, insulin or the structurally related GLP-1 peptides, exendin (1-39)amide and exendin(9-39)amide, and iii) to explore possible differences in the responsiveness to these agents between normal and diabetic subjects. Apart from the much higher basal PI3K activity and impaired response to insulin of p44/42 MAP kinases in the diabetic patients, the changes in enzyme activity caused by either hormone or peptide, although not identical, were essentially comparable. Nevertheless, significant differences in glucose transport and metabolism parameters were observed in the diabetic patients vs. normal subjects: in the diabetic patients, basal 2-deoxy-glucose uptake and glycogen synthase a activity were lower, accompanied by a similar increasing effect of GLP-1 or insulin; yet, the basal value for glycogen synthesis was higher, coinciding with a lesser relative increment in response to GLP-1 or insulin.

Effect of bombesin receptor subtype-3 and its synthetic agonist on signaling, glucose transport and metabolism in myocytes from patients with obesity and type 2 diabetes.

Bombesin receptor subtype-3 (BRS-3) is an orphan G-protein-coupled receptor (GPCR) member of the bombesin receptor family. Several studies have suggested an association between obesity, alterations in glucose metabolism, diabetes and the BRS-3 receptor. In this study, we focused on patients simultaneously diagnosed with obesity and type 2 diabetes (OB/T2D). The analysis of BRS-3 expression in the skeletal muscle of these patients revealed a marked decrease in the expression of BRS-3 at the mRNA (23.6 ± 1.3-fold downregulation, p<0.0001) and protein level (49 ± 7% decrease, p<0.05) compared to the normal patients (no obesity and diabetes). Moreover, in cultured primary myocytes from patients with OB/T2D, the synthetic BRS-3 agonist, [D-Try6,ß-Ala11,Phe13,Nle14]bombesin6-14, significantly increased the phosphorylation levels of mitogen-activated protein kinase (MAPK), p90RSK1, protein kinase B (PKB) and p70s6K. Specifically, the ligand at 10-11 M induced the maximal phosphorylation of MAPKs (p42, 159 ± 15% of the control; p44, 166 ± 11% of the control; p<0.0001) and p90RSK1 (148 ± 2% of the control, p<0.0001). The basal phosphorylation levels of all kinases were reduced (p<0.05) in the patients with OB/T2D compared to the normal patients. Furthermore, the BRS-3 agonist stimulated glucose transport, which was already detected at 10-12 M (133 ± 9% of the control), reached maximal levels at 10-11 M (160 ± 9%, p<0.0001) and was maintained at up to 10-8 M (overall mean, 153 ± 7%; p < 0.007). This effect was less promiment than that attained with 10-8 M insulin (202 ± 9%, p = 0.009). The effect of the agonist on glycogen synthase a activity achieved the maximum effect at 10-11 M (165 ± 16% of the control; p<0.0001), which did not differ from that observed with higher concentrations of the agonist. These results suggest that muscle cells isolated from patients with OB/T2D have extremely high sensitivity to the synthetic ligand, and the effects are particularly observed on MAPK and p90RSK1 phosphorylation, as well as glucose uptake. Moreover, our data indicate that BRS-3 may prove to be useful as a potential therapeutic target for the treatment of patients with OB/T2D.

[EFFECTS OF WEIGHT LOSS AFTER BARIATRIC SURGERY ON PULMONARY FUNCTION TESTS AND OBSTRUCTIVE SLEEP APNEA IN MORBIDLY OBESE WOMEN]. / EFECTO DE LA PÉRDIDA DE PESO TRAS LA CIRUGÍA BARIÁTRICA SOBRE LA FUNCIÓN RESPIRATORIA Y EL SÍNDROME DE APNEAS-HIPOPNEAS DEL SUEÑO EN MUJERES CON OBESIDAD MÓRBIDA.

INTRODUCTION: obesity impacts on respiratory function and also it acts as a risk factor for obstructive sleep apnea (OSA). AIMS: to study the effects of bariatric surgery on pulmonary function tests and on OSA in morbidly obese women over 4 years. METHODS: fifteen morbidly obese women (mean body mass index [BMI] 50.52 ± 12.71 kg.m-2, mean age 40.13 ± 10.06 years) underwent pulmonary function tests (PFT) in two opportunities (before and after weight loss surgery). PFT included spirometry, body plethysmography and measure of maximal inspiratory mouth pressure (PImax) and of tension-time index for inspiratory muscles. Also, in both opportunities, resting arterial blood gas tensions were evaluated and a full night sleep register was performed. RESULTS: BMI significantly decreased after bariatric surgery (-44.07 kg.m-2 [CI 95% -38.32 - -49.81]). Also, there was a significantly increase in forced expiratory volume in 1 second (FEV1) (p < 0.01), forced vital capacity (FVC) (p < 0.01), expiratory reserve volume (ERV) (p = 0.040), functional residual capacity (FRC) (p = 0.009) and a decline in airways resistance (Raw) (p = 0.018). Concerning sleep registers, apnea hypopnea index (p = 0.001) and desaturation index (p = 0.001) were also reduced after weight loss. Improve in ERV had a significant correlation with weight loss (r = 0.774, p = 0.024). Conclussions: pulmonary function tests and apnea hypopnea index improve after bariatric surgery in mor bidly obese women. Improvement of ERV is well correlated with weight loss.

Introducción: la obesidad afecta a la función respiratoria e incrementa el riesgo de síndrome de apneas-hipopneas del sueño (SAHS). Objetivo: evaluar el efecto de la cirugía bariátrica, en mujeres con obesidad mórbida, sobre la función respiratoria y sobre el índice de apneas-hipopneas (IAH) tras dos años de seguimiento. Métodos: se incluyeron 15 mujeres (índice de masa corporal [IMC] medio 50,52 ± 12,71 kg.m-2, edad media 40,13 ± 10,06 años). Los enfermos fueron analizados en dos fases: previo a la cirugía bariátrica y tras dos años de la misma. En cada visita se valoraron las medidas antropométricas y se realizaron pruebas de función respiratoria consistentes en espirometría, pletismografía, medida de la presión inspiratoria máxima y del índice de tensión-tiempo de los músculos inspiratorios, así como análisis de gases arteriales. Por último, también se efectuó una poligrafía cardiorrespiratoria durante el sueño. Resultados: tras la cirugía bariátrica el IMC disminuyó en 44,07 kg.m-2 (IC 95% 38,32 ­ 49,81). De igual forma, se observaron incrementos significativos en el volumen espiratorio forzado al primer segundo (FEV1) (p < 0,01), la capacidad vital forzada (FVC) (p < 0,01), el volumen de reserva espiratorio (ERV) (p = 0,040), la capacidad funcional residual (FRC) (p = 0,009) y la resistencia de las vías aéreas (Raw) (p = 0,018). Por otra parte, el IAH (p = 0,001) y el índice de desaturación de oxígeno (p = 0,001) disminuyeron tras la cirugía. Se observó una correlación significativa entre el grado de pérdida de peso y el incremento del ERV (0,774, p = 0,024). Conclusiones: tras dos años desde la cirugía bariátrica se siguen observando mejorías significativas en la función respiratoria y en la gravedad del SAHS. La mejoría del ERV estaría en relación directa con los niveles de peso perdido.

The upper airway and obstructive sleep apnea in morbidly obese women.

STUDY OBJECTIVES: We are currently carrying out a study on the changes of the upper airway in morbidly obese women and the relationship of the upper airway with the severity of obstructive sleep apnea syndrome (OSAS). This study is similar to the study by Fogel RB et al, which appeared in Sleep 2003;2:150-5. DESIGN: Patients underwent a cardiorespiratory polygraphic sleep study, respiratory function test (spirometry, plethysmography, arterial blood gas analysis), and computed tomographic studies of the upper airway. PATIENTS: Thirteen morbidly obese women being evaluated for weight-reduction surgery. RESULTS: OSAS was present in all the patients. We found a positive correlation between the uvula diameter and age (r = 0.63, P = .02) and a negative correlation between the area of the oropharynx at the end of maximal expiration and the number of desaturations greater than 4% per hour (r = -0.58, P = .03). In the subgroup of patients with severe OSAS (7 cases), the area of the oropharynx at maximal inspiration had a negative correlation with the apnea-hypopnea index (r = -0.78, P = .03). The resistances of the airway positively correlated with apnea-hypopnea index (r = 0.89, P = .003), apnea index (r = 0.90, P = .03), and desaturation index (r = 0.91, P = .02). The Pao2 had a negative correlation with apnea-hypopnea index (r = -0.63, P = .02), apnea index (r = -0.65, P = .02), and desaturation index (r = -0.66, P = .02). CONCLUSIONS: Our results confirm that, in morbid obese women, airway resistance is higher in those patients with OSAS. We propose that airway resistance and Pao2 can also constitute a good predictor of apnea severity and that a reduction in the cross-sectional area of the airway at the level of the nasopharynx could be related to the severity of OSAS.

Bombesin receptor subtype-3 (BRS-3), a novel candidate as therapeutic molecular target in obesity and diabetes.

BRS-3 KO-mice developed obesity and unbalanced glucose metabolism, suggesting an important role of BRS-3 receptor in glucose homeostasis. We explored BRS-3 expression in skeletal muscle from normal, obese or type-2 diabetic (T2D) patients, and the effect of [D-Phe(6), ß-Ala(11),Phe(13),Nle(14)]bombesin(6-14)-BRS-3-agonist-peptide (BRS-3-AP) - on glucose-related effects, before or after BRS-3 gene silencing. In muscle tissue and primary cultured myocytes from altered metabolic states, BRS-3 gene/protein expressions were down-regulated. In normal, obese and T2D cells: A) BRS-3-AP as insulin enhanced BRS-3 and GLUT-4 mRNA/protein levels; improving glucotransporter translocation to plasma membrane, and B) BRS-3-AP caused a concentration-related-stimulation of glucose transport, being obese and T2D myocytes more sensitive to the ligand than normal. Wortmannin and PD98059, but not rapamycin, abolished the stimulatory action of BRS-3-AP on glucose transport. BRS-3 plays an important role in glucose metabolism, and could be use as a molecular target, and/or its ligand, as a therapeutic agent for obesity and diabetes treatments.