Isthmin-1 (ISM1), a novel adipokine that reflects abdominal adipose tissue distribution in individuals with obesity.

BACKGROUND: The assessment of obesity-related health risks has traditionally relied on the Body Mass Index and waist circumference, but their limitations have propelled the need for a more comprehensive approach. The differentiation between visceral (VIS) and subcutaneous (SC) fat provides a finer-grained understanding of these risks, yet practical assessment methods are lacking. We hypothesized that combining the SC-VIS fat ratio with non-invasive biomarkers could create a valuable tool for obesity-related risk assessment. METHODS AND RESULTS: A clinical study of 125 individuals with obesity revealed significant differences in abdominal fat distribution measured by CT-scan among genders and distinct models of obesity, including visceral, subcutaneous, and the SC/VIS ratio. Stratification based on these models highlighted various metabolic changes. The SC/VIS ratio emerged as an excellent metric to differentiate metabolic status. Gene expression analysis identified candidate biomarkers, with ISM1 showing promise. Subsequent validation demonstrated a correlation between ISM1 levels in SC and plasma, reinforcing its potential as a non-invasive biomarker for fat distribution. Serum adipokine levels also correlated with the SC/VIS ratio. The Receiver Operating Characteristic analysis revealed ISM1's efficacy in discriminating individuals with favorable metabolic profiles based on adipose tissue distribution. Correlation analysis also suggested that ISM1 was involved in glucose regulation pathways. CONCLUSION: The study's results support the hypothesis that the SC-VIS fat ratio and its derived non-invasive biomarkers can comprehensively assess obesity-related health risks. ISM1 could predict abdominal fat partitioning and be a potential biomarker for evaluating obesity-related health risks.

Evaluation of Cardiovascular Risk Factors after Hepatitis C Virus Eradication with Direct-Acting Antivirals in a Cohort of Treatment-Naïve Patients without History of Cardiovascular Disease.

BACKGROUND: Hepatitis C virus (HCV) produces changes at multiple levels in host metabolism, especially in lipid profile and cardio-metabolic risk. It is unclear how HCV eradication by direct-acting antivirals (DAAs) modifies those changes. OBJECTIVE: To evaluate the impact of DAA treatment on different risk factors associated with cardiovascular disease. METHODS: Prospective study with two-year follow-up. All patients treated with DAAs in the Liver Clinic of a tertiary hospital were included. Patients co-infected with HBV or HIV, with other causes of liver disease, on lipid-lowering treatment, pregnant, or with previous HCV treatment were excluded. The results were analyzed using linear mixed models. RESULTS: 167 patients (53% female, 9.6% cirrhosis) were included. Low plasma lipid levels were observed before initiating HCV eradication. During the first year after treatment with DAA, we observed a sustained increase in cholesterol, triglycerides, HDL cholesterol (only in men), and LDL-cholesterol levels. An ameliorated glycemic control was also observed with a decrease in fasting insulin and reduced HOMA. Iron metabolism and coagulation function also improved with lower levels of serum ferritin and prothrombin activity; these biochemical changes resulted in a new diagnosis of hypercholesterolaemia in 17.4% of patients, requiring initiation of statins in 15%. Two non-fatal cardiovascular events were observed during the first 2 years of follow-up. CONCLUSIONS: DAA treatments returned plasma lipids to the normal range without increasing either the occurrence of cardiovascular events or the consumption of lipid-lowering medication beyond what is normal in a sex- and age-matched population.

Randomized Clinical Trial: Effects of ß-Hydroxy-ß-Methylbutyrate (HMB)-Enriched vs. HMB-Free Oral Nutritional Supplementation in Malnourished Cirrhotic Patients.

ß-Hydroxy-ß-methylbutyrate (HMB) supplementation increases muscle and strength mass in some muscle-wasting disorders. Malnutrition and sarcopenia are often present in liver cirrhosis. We aimed to investigate the effects of oral HMB supplementation on changes in body composition and liver status in patients with cirrhosis and malnutrition. In a randomized, controlled, double-blind trial, 43 individuals were randomized to receive twice a day and for 12 weeks an oral nutritional supplement (ONS) enriched with 1.5 g of calcium HMB per bottle or another supplement with similar composition devoid of HMB. Inclusion criteria were liver cirrhosis with at least one previous decompensation and clinical malnutrition. Liver function, plasma biochemistry analyses, and physical condition assessment were carried out at baseline, then after six and 12 weeks of supplementation. A total of 34 patients completed the clinical trial. An improvement in liver function and an increase in fat mass index were observed in both groups. None of the two ONS changed the fat-free mass. However, we observed an upward trend in handgrip strength and a downward trend in minimal hepatic encephalopathy in the HMB group. At the end of the trial and regardless of the supplement administered, fat mass content increased with no change in fat-free mass, while liver function scores and nutritional analytic markers also improved.

Amino Acid Profile in Malnourished Patients with Liver Cirrhosis and Its Modification with Oral Nutritional Supplements: Implications on Minimal Hepatic Encephalopathy.

Low plasma levels of branched chain amino acids (BCAA) in liver cirrhosis are associated with hepatic encephalopathy (HE). We aimed to identify a metabolic signature of minimal hepatic encephalopathy (MHE) in malnourished cirrhotic patients and evaluate its modification with oral nutritional supplements (ONS) enriched with ß-Hydroxy-ß-methylbutyrate (HMB), a derivative of the BCAA leucine. Post hoc analysis was conducted on a double-blind placebo-controlled trial of 43 individuals with cirrhosis and malnutrition, who were randomized to receive, for 12 weeks, oral supplementation twice a day with either 220 mL of Ensure® Plus Advance (HMB group, n = 22) or with 220 mL of Ensure® Plus High Protein (HP group, n = 21). MHE evaluation was by psychometric hepatic encephalopathy score (PHES). Compared to the HP group, an HMB-specific treatment effect led to a larger increase in Val, Leu, Phe, Trp and BCAA fasting plasma levels. Both treatments increased Fischer's ratio and urea without an increase in Gln or ammonia fasting plasma levels. MHE was associated with a reduced total plasma amino acid concentration, a reduced BCAA and Fischer´s ratio, and an increased Gln/Glu ratio. HMB-enriched ONS increased Fischer´s ratio without varying Gln or ammonia plasma levels in liver cirrhosis and malnutrition, a protective amino acid profile that can help prevent MHE.

[Beginnings, evolution and current situation of the Newborn Screening Programs in Spain.] / Inicio, evolución y situación actual de los Programas de Cribado Neonatal en España.

Newborn Screening Programs (NSP) in Spain were born in the city of Granada in 1968. Till the 1980s, they were developed around the so-called "National Plan for Preventing Subnormality", covering up to 30% of the Spanish newborns. From 1982, when the health system management was transferred to the different autonomous regions, the NSP began to expand, and the bases to transform them into an organized and multidisciplinary activity, integrated and coordinated from the National Health System were settled. Despite this expansion, it is not until the 1990s when their coverage reaches almost 100% newborns in Spain. NSP grew up asymmetrically across the different autonomous regions. In 2005 and 2006 the scientific societies SEQC (Spanish Society of Clinical Chemistry) and AECNE (Spanish Society of Newborn Screening), coordinated by the Health Promotion Area of the General Directorate of Public Health, gathered together the necessary information to elaborate a report on the NSP in Spain addressed to the Interterritorial Council of the National Health System. In July 2013, that Council approved the seven diseases that should be part of each region newborn screening panel, being the first step towards the NSP harmonization in Spain. Currently, the NSP include between 8 and 29 diseases in their panels, thus more still more efforts are needed in order to achieve a higher uniformity.

Los Programas de Cribado Neonatal (PCN) nacen en España en Granada en el año 1968. Posteriormente, y hasta los años 80, se fueron desarrollando en torno al llamado "Plan Nacional de Prevención de la Subnormalidad" con una cobertura cercana al 30% de los recién nacidos españoles. A partir de 1982, con el inicio de la gestión de la sanidad a las comunidades autónomas (CCAA), los PCN se expandieron y se comenzaron a sentar las bases para que éstos se convirtieran en una actividad organizada y multidisciplinar, integrados y coordinados desde el Sistema de Salud. A pesar de dicha expansión no es hasta el inicio de la década de los 90 cuando se consigue una cobertura próxima al 100% de los RN en España. Los PCN fueron creciendo de forma muy asimétrica en las diferentes CCAA y en los años 2005 y 2006 las Sociedades Científicas SEQC (Sociedad Española de Química Clínica) y AECNE (Asociación Española de Cribado Neonatal), con la coordinación del Área de Promoción de la Salud de la Dirección General de Salud Pública, recopilaron la información y elaboraron un informe, sobre los PCN en España para el Consejo Interterritorial del sistema Nacional de Salud (CISNS). En julio de 2013 este Consejo aprobó las siete enfermedades que debían formar parte del panel de detección de los PCN territoriales, primer paso hacia la armonización de estos programas. Actualmente, los PCN incluyen entre 8 y 29 enfermedades por lo que es necesario seguir trabajando para conseguir una mayor uniformidad.

Identifying and overcoming barriers to harmonize newborn screening programs through consensus strategies.

The benefits of newborn screening (NBS) programs have been widely demonstrated after more than 50 years since first established. NBS enables the detection of the disease before the child shows clinical symptoms, allowing clinicians to act early and facilitating appropriate interventions to prevent or improve adverse outcomes. Delay or lack of medical intervention in these infants may lead to developmental delay, severe disability, or premature death. NBS programs have grown exponentially both in the number of diseases screened and in complexity, creating controversy. New technological advances, as well as the emergence of new therapies that require early disease detection, have allowed for the inclusion of new diseases in NBS screening programs. However, different countries and even different regions have in turn adopted very diverse strategies and diagnostic algorithms when it comes to NBS. There are many factors responsible for these differences, such as the health care system, available funds, local politics, professional groups, and others that depend on the position taken by policymakers. These differences in NBS have led to discrepancies in detection opportunities between countries or regions, which has led to many varied attempts to harmonize NBS programs but not all have been equally satisfactory. Some countries have achieved good results, but always within their borders. Therefore, there are still many differences between NBS programs at the international level that must be overcome. These advances have also brought considerable uncertainty regarding ethical aspects and balance between benefits and harms. For this reason, and so that the situation of disparity in the global NBS programs can be minimized, health authorities must work to develop uniform criteria for decision-making and to take a further step toward harmonization. To do so, it is necessary to identify the crucial factors that lead to the adoption of different NBS programs worldwide, in order to analyze their influence and find ways to overcome them.

Serum protein profile analysis in lysosomal storage disorders patients.

INTRODUCTION: Serum protein electrophoresis (SPE) is a well-established technique to identify alterations in plasma protein profiles, caused by diseases as multiple myeloma (MM). In addition, it could be a cost-effective technique to discover new plasma biomarkers. Relation between MM and lysosomal storage diseases (LSDs) as Gaucher disease has been set out but, it has not been evaluated on other LSDs nor the utility of the SPE as first step on LSDs biomarkers discovery projects. MATERIALS AND METHODS: Stored plasma samples at diagnosis from several LSDs patients underwent analysis. Quality control was checked prior to the SPE was analyzed by capillary electrophoresis. The analysis for monoclonal spikes and the differences between each fraction on patients' samples vs the control data previously published, were evaluated. Furthermore, immunoprotein quantification and free light chains ratio were done by nephelometry and turbidimetry. RESULTS: Seventy-five samples of LSD patients at diagnosis, were assessed. The frequency of the MGUS on LSDs patients was not higher than in general population whereas one lysosomal acid lipase deficiency infant showed increased IgA and kappa deviation. Regarding to the usefulness of SPE in biomarkers discovery, statistically significant differences were observed on SPE fractions between LSDs and healthy population. DISCUSSION: The evaluation of SPE fractions can be a useful tool to understand pathophysiologic aspects in LDSs and, to simplify new marker discovery projects. In some of them, the MGUS appearance is a risk factor for the MM development despite its frequency is not increased on the studied LSDs at diagnosis.

Criterios de extracción de muestra en situaciones especiales del cribado neonatal. Revisión / Criteria for specimen collection in special situations of newborn screening. Review

La espectrometría de masas en tándem (MS-MS) ha permitido ampliar el alcance del cribado neonatal. Eso hace más complicado determinar el momento más adecuado para la toma de muestra, sobre todo en recién nacidos prematuros y/o bajo peso y/o ingresados en unidades neonatales. El objetivo del presente estudio ha sido revisar las normas de toma de muestra de los distintos programas en estas situaciones, a nivel nacional e internacional. Se obtienen los datos a través de páginas web de salud pública, de plataformas de búsqueda o por contacto con los centros. Existe gran disparidad de criterios para la toma de una nueva muestra, incluso dentro de un mismo país. La limitación de información disponible, hizo imposible obtener resultados de muchos países, en particular de África, Asia o Latinoamérica. A pesar de que cada vez más estados se acogen a las recomendaciones del Clinical and Laboratory Standards Institute u otros organismos internacionales, el aumento del coste que implica, hace muy difícil conseguir la estandarización

The most significant breakthrough in the newborn screening (NBS) programs was the introduction of the tandem mass spectrometry (MS-MS) to the laboratory, which makes it possible to detect multiple disorders. However, it is difficult to choose the ideal time for the specimen collection, particularly in preterm, low birth weight, and sick newborns. The aim of this study was to revise the protocols, in national and international programs for specimen collection in these newborns. Data were collected from web pages of public health, internet searches, and contact with the laboratories. The results showed a great disparity in criteria for a new specimen collection, as well as among different centres within a country. It has been difficult to obtain this information from many countries in Africa, Asia, and Latin America. Although an increasing number of laboratories follow the recommendations of the Clinical and Laboratory Standards Institute or other international guidelines, the increased cost involved makes standardisation difficult

Newborn screening for homocystinurias: Recent recommendations versus current practice.

PURPOSE: To assess how the current practice of newborn screening (NBS) for homocystinurias compares with published recommendations. METHODS: Twenty-two of 32 NBS programmes from 18 countries screened for at least one form of homocystinuria. Centres provided pseudonymised NBS data from patients with cystathionine beta-synthase deficiency (CBSD, n = 19), methionine adenosyltransferase I/III deficiency (MATI/IIID, n = 28), combined remethylation disorder (cRMD, n = 56) and isolated remethylation disorder (iRMD), including methylenetetrahydrofolate reductase deficiency (MTHFRD) (n = 8). Markers and decision limits were converted to multiples of the median (MoM) to allow comparison between centres. RESULTS: NBS programmes, algorithms and decision limits varied considerably. Only nine centres used the recommended second-tier marker total homocysteine (tHcy). The median decision limits of all centres were ≥ 2.35 for high and ≤ 0.44 MoM for low methionine, ≥ 1.95 for high and ≤ 0.47 MoM for low methionine/phenylalanine, ≥ 2.54 for high propionylcarnitine and ≥ 2.78 MoM for propionylcarnitine/acetylcarnitine. These decision limits alone had a 100%, 100%, 86% and 84% sensitivity for the detection of CBSD, MATI/IIID, iRMD and cRMD, respectively, but failed to detect six individuals with cRMD. To enhance sensitivity and decrease second-tier testing costs, we further adapted these decision limits using the data of 15 000 healthy newborns. CONCLUSIONS: Due to the favorable outcome of early treated patients, NBS for homocystinurias is recommended. To improve NBS, decision limits should be revised considering the population median. Relevant markers should be combined; use of the postanalytical tools offered by the CLIR project (Collaborative Laboratory Integrated Reports, which considers, for example, birth weight and gestational age) is recommended. tHcy and methylmalonic acid should be implemented as second-tier markers.

PTRF acts as an adipokine contributing to adipocyte dysfunctionality and ectopic lipid deposition

Adipose tissue (AT) expands under obesogenic conditions. Yet, when the growth exceeds a certain limit, AT becomes dysfunctional and surplus lipids start depositing ectopically. Polymerase I and transcription release factor (PTRF) has been proposed as a mechanism leading to a dysfunctional AT by decreasing the adipogenic potential of human adipocyte precursors. However, whether or not PTRF can be secreted by the adipocytes into the bloodstream is not yet known. For this work, PTRF presence was investigated in plasma. We also produced a recombinant PTRF (rPTRF) and examined its impact on the functional interactions between the adipocyte and the hepatocyte in vitro. We demonstrated that PTRF can be found in human plasma, and is at least in part, carried by exosomes. In vitro treatment with rPTRF increased the hypertrophy and senescence of 3T3-L1 adipocytes. In turn, those rPTRF-treated adipocytes increased lipid accumulation in hepatocytes. Lastly, we found a positive correlation between circulating PTRF and the concentration of PTRF in the visceral fat depot. All these findings point toward the presence of an enlarged and dysfunctional visceral adipose tissue which secretes PTRF. This circulating PTRF behaves as an adipokine and may partially contribute to the well-known detrimental effects of visceral fat accumulation

PTRF acts as an adipokine contributing to adipocyte dysfunctionality and ectopic lipid deposition.

Adipose tissue (AT) expands under obesogenic conditions. Yet, when the growth exceeds a certain limit, AT becomes dysfunctional and surplus lipids start depositing ectopically. Polymerase I and transcription release factor (PTRF) has been proposed as a mechanism leading to a dysfunctional AT by decreasing the adipogenic potential of human adipocyte precursors. However, whether or not PTRF can be secreted by the adipocytes into the bloodstream is not yet known. For this work, PTRF presence was investigated in plasma. We also produced a recombinant PTRF (rPTRF) and examined its impact on the functional interactions between the adipocyte and the hepatocyte in vitro. We demonstrated that PTRF can be found in human plasma, and is at least in part, carried by exosomes. In vitro treatment with rPTRF increased the hypertrophy and senescence of 3T3-L1 adipocytes. In turn, those rPTRF-treated adipocytes increased lipid accumulation in hepatocytes. Lastly, we found a positive correlation between circulating PTRF and the concentration of PTRF in the visceral fat depot. All these findings point toward the presence of an enlarged and dysfunctional visceral adipose tissue which secretes PTRF. This circulating PTRF behaves as an adipokine and may partially contribute to the well-known detrimental effects of visceral fat accumulation.

Knockdown of PTRF ameliorates adipocyte differentiation and functionality of human mesenchymal stem cells.

Healthy expansion of human adipose tissue requires mesenchymal stem cells (hMSC) able to proliferate and differentiate into mature adipocytes. Hence, characterization of those factors that coordinate hMSC-to-adipocyte transition is of paramount importance to modulate the adipose tissue expansion. It has been previously reported that the adipogenic program of hMSC can be disrupted by upregulating caveolar proteins, and polymerase I and transcript release factor (PTRF) is an integral component of caveolae, highly expressed in adipose tissue. Here, we hypothesized that the role of PTRF in adipocyte functionality might stem from an effect on hMSC. To test this hypothesis, we isolated hMSC from the subcutaneous fat depot. We found an upregulated expression of the PTRF associated with decreased adipogenic potential of hMSC, likely due to the existence of senescent adipocyte precursors. Employing short hairpin RNA-based constructs to stably reduce PTRF, we were able to restore insulin sensitivity and reduced basal lipolysis and leptin levels in human adipocytes with high levels of PTRF. Additionally, we pinpointed the detrimental effect caused by PTRF on the adipose tissue to the existence of senescent adipocyte precursors unable to proliferate and differentiate into adipocytes. This study provides evidence that impaired adipocyte functionality can be corrected, at least partially, by PTRF downregulation and warrants further in vivo research in patients with dysfunctional adipose tissue to prevent metabolic complications.

The FAT expandability (FATe) Project: Biomarkers to determine the limit of expansion and the complications of obesity.

BACKGROUND: Obesity is an excessive accumulation of fat frequently, but not always, associated with health problems, mainly type 2 diabetes and cardiovascular disease. During a positive energy balance, as caused by excessive intake or sedentary lifestyle, subcutaneous adipose tissue expands and accumulates lipids as triglycerides. However, the amount of adipose tissue per se is unlikely to be the factor linking obesity and metabolic complications. The expandability hypothesis states that, if this positive energy balance is prolonged, a point is eventually reached where subcutaneous adipose tissue can not further expand and energy surplus no longer can be safely stored. Once the limit on storage capacity has been exceeded, the dietary lipids start spilling and accumulate ectopically in other organs (omentum, liver, muscle, pancreas) forming lipid byproducts toxic to cells. METHODS/DESIGN: FATe is a multidisciplinary clinical project aimed to fill gaps that still exist in the expandability hypothesis. Imaging techniques (CT-scan), metabolomics, and transcriptomics will be used to identify the factors that set the limit expansion of subcutaneous adipose tissue in a cohort of caucasian individuals with varying degrees of adiposity. Subsequently, a set of biomarkers that inform the individual limits of expandability will be developed using computational and mathematical modeling. A different validation cohort will be used to minimize the risk of false positive rates and increase biomarkers' predictive performance. DISCUSSION: The work proposed here will render a clinically useful screening method to predict which obese individuals will develop metabolic derangements, specially diabetes and cardiovascular disease. This study will also provide mechanistic evidence that promoting subcutaneous fat expansion might be a suitable therapy to reduce metabolic complications associated with positive energy balance characteristic of Westernized societies.