Developing a model to predict the early risk of hypertriglyceridemia based on inhibiting lipoprotein lipase (LPL): a translational study

Hypertriglyceridemia; Inhibiting lipoprotein lipaseHipertrigliceridèmia; Inhibició de la lipoproteïna lipasaHipertrigliceridemia; Inhibición de la lipoproteína lipasaHypertriglyceridemia (HTG) is an independent risk factor for atherosclerotic cardiovascular disease (ASCVD). One of the multiple origins of HTG alteration is impaired lipoprotein lipase (LPL) activity, which is an emerging target for HTG treatment. We hypothesised that early, even mild, alterations in LPL activity might result in an identifiable metabolomic signature. The aim of the present study was to assess whether a metabolic signature of altered LPL activity in a preclinical model can be identified in humans. A preclinical LPL-dependent model of HTG was developed using a single intraperitoneal injection of poloxamer 407 (P407) in male Wistar rats. A rat metabolomics signature was identified, which led to a predictive model developed using machine learning techniques. The predictive model was applied to 140 humans classified according to clinical guidelines as (1) normal, less than 1.7 mmol/L; (2) risk of HTG, above 1.7 mmol/L. Injection of P407 in rats induced HTG by effectively inhibiting plasma LPL activity. Significantly responsive metabolites (i.e. specific triacylglycerols, diacylglycerols, phosphatidylcholines, cholesterol esters and lysophospholipids) were used to generate a predictive model. Healthy human volunteers with the impaired predictive LPL signature had statistically higher levels of TG, TC, LDL and APOB than those without the impaired LPL signature. The application of predictive metabolomic models based on mechanistic preclinical research may be considered as a strategy to stratify subjects with HTG of different origins. This approach may be of interest for precision medicine and nutritional approaches.This research was financially supported by the Catalan Government through the funding grant ACCIÓ-Eurecat (PRIV2019-PREVENTOMICS) and by the Centre for the Development of Industrial Technology (CDTI) of the Spanish Ministry of Science and Innovation under grant agreement: TECNOMIFOOD project. CER-20191010

A Pilot Study for Metabolic Profiling of Obesity-Associated Microbial Gut Dysbiosis in Male Wistar Rats

Obesity is one of the most incident and concerning disease worldwide. Definite strategies to prevent obesity and related complications remain elusive. Among the risk factors of the onset of obesity, gut microbiota might play an important role in the pathogenesis of the disease, and it has received extensive attention because it affects the host metabolism. In this study, we aimed to define a metabolic profile of the segregated obesity-associated gut dysbiosis risk factor. The study of the metabolome, in an obesity-associated gut dysbiosis model, provides a relevant way for the discrimination on the different biomarkers in the obesity onset. Thus, we developed a model of this obesity risk factors through the transference of gut microbiota from obese to non-obese male Wistar rats and performed a subsequent metabolic analysis in the receptor rats. Our results showed alterations in the lipid metabolism in plasma and in the phenylalanine metabolism in urine. In consequence, we have identified metabolic changes characterized by: (1) an increase in DG:34:2 in plasma, a decrease in hippurate, (2) an increase in 3-HPPA, and (3) an increase in o-coumaric acid. Hereby, we propose these metabolites as a metabolic profile associated to a segregated dysbiosis state related to obesity disease

Alterations in Metabolome and Microbiome Associated with an Early Stress Stage in Male Wistar Rats: A Multi-Omics Approach

Stress disorders have dramatically increased in recent decades becoming the most prevalent psychiatric disorder in the United States and Europe. However, the diagnosis of stress disorders is currently based on symptom checklist and psychological questionnaires, thus making the identification of candidate biomarkers necessary to gain better insights into this pathology and its related metabolic alterations. Regarding the identification of potential biomarkers, omic profiling and metabolic footprint arise as promising approaches to recognize early biochemical changes in such disease and provide opportunities for the development of integrative candidate biomarkers. Here, we studied plasma and urine metabolites together with metagenomics in a 3 days Chronic Unpredictable Mild Stress (3d CUMS) animal approach that aims to focus on the early stress period of a well-established depression model. The multi-omics integration showed a profile composed by a signature of eight plasma metabolites, six urine metabolites and five microbes. Specifically, threonic acid, malic acid, alpha-ketoglutarate, succinic acid and cholesterol were proposed as key metabolites that could serve as key potential biomarkers in plasma metabolome of early stages of stress. Such findings targeted the threonic acid metabolism and the tricarboxylic acid (TCA) cycle as important pathways in early stress. Additionally, an increase in opportunistic microbes as virus of the Herpesvirales was observed in the microbiota as an effect of the primary stress stages. Our results provide an experimental biochemical characterization of the early stage of CUMS accompanied by a subsequent omic profiling and a metabolic footprinting that provide potential candidate biomarkers

Modulation of mir-33 and mir-122 by dietary polyphenols

mi(cro)RNAs are becoming relevant for the epigenetic control of metabolism. miRNAs are small non-conding RNAs of approximately 19-24 nucleotides in length that regulate the expression of target genes at post-transcriptional level. Specifically, miR-33 is a critical regulator of cholesterol and fatty acid homeostasis by repressesing fatty acid oxidation, hepatic HDL biogenesis and cholesterol efflux to HDL. Furthermore, miR-122, which is liver-specific, regulates several genes that control fatty acid and triglyceride biosynthesis. On the other hand, dietary components, such polyphenols, are reported to have benefitial effects againts cardiovascular diseases, reducing triglycerides and/or cholesterol plasma levels. Hence, the main objective of this thesis was to evaluate the capacity of polyphenols, mainly proanthocyanidins, to modulate miR-33 and miR-122 in different physiological situations. Result showed that polyphenols modulate these miRNAs and their target genes in liver, suggesting that miRNAs regulation are a new molecular mechanims used by some polyphenols to modulate lipid metabolism and to improve the atherogenic profile. Moreover, NMR studies showed that polyphenols directly bind to miR-33 and miR-122, suggesting that polyphenols can modulate cell miRNAs levels by a direct interaction.Las proantocianidinas, que son agentes hipolipidémicos, son los polifenoles mayoritarios en la dieta humana que ayudan a combatir factores de riesgo contra la obesidad y la enfermedad cardiovascular. Por otro lado, los mi(cro)RNAs participan en la regulación de genes del metabolismo lipídico y, el efecto de las proantocianidinas sobre dichos miRNAs es desconocido. Por ello, el principal objetivo de la tesis ha sido evaluar si los polifenoles, principalmente proantocianidinas, modulan miR-33 i miR-122, dos miRNAs involucrados en el metabolismo lipídico. Para ello se usaron modelos animales y celulares. Los resultados muestran que los compuestos de la dieta modulan estos miRNAs, mejorando el metabolismo lipídico, y que los polifenoles se unen directamente a miR-33 i miR-122. En conclusión, las proantocianidinas al modular los níveles de miR-33 i miR-122 pueden ser útiles para tratar enfermedades metabólicas. Además, estos resultados también sugieren que la modulación los miRNAs puede ser un mecanismo molecular usado por los componentes de la dieta por el que mejoran un perfil aterogénic

Beneficial effects of the Mediterranean spices and aromas on non-alcoholic fatty liver disease

Background Non-alcoholic fatty liver disease (NAFLD) can be regarded as the hepatic manifestation of metabolic syndrome (MS), which has a high prevalence in Western-lifestyle countries. NAFLD can progress to more severe pathologies such as cirrhosis and fibrosis, thus worsening individuals\u2019 life quality and increasing health costs. In the last decades, many efforts have been made in order to understand the molecular mechanisms of NAFLD and how to cure it. It has become clear that alimentary regimen is of primary importance for preventing/treating MS and NAFLD. Scope and approach Beneficial effects of the Mediterranean diet (MedDiet) on MS and NAFLD are now recognized and can be ascribed to low calories intake but also to abundance of anti-oxidant and anti-inflammatory compounds which are present in fruit and vegetables as well as in herbs and spices widely used to flavor traditional Mediterranean dishes. The aim of this review is to summarize briefly NAFLD molecular pathways and therapies, while focusing on the beneficial effects and mechanisms of action of the most used Mediterranean aromatic plants and spices (MAPS). Key findings and conclusions All MAPS reviewed here have been documented to exert hepatoprotective actions and almost the totality has a direct or indirect lipid-lowering effect on the liver, accompanied by amelioration of other MS parameters. We suggest that culinary MAPS use can contribute to the health benefits of MedDiet without the danger of adverse effects that can occur when the active compounds are used in pharmacological doses

A Pilot Study for Metabolic Profiling of Obesity-Associated Microbial Gut Dysbiosis in Male Wistar Rats

Obesity is one of the most incident and concerning disease worldwide. Definite strategies to prevent obesity and related complications remain elusive. Among the risk factors of the onset of obesity, gut microbiota might play an important role in the pathogenesis of the disease, and it has received extensive attention because it affects the host metabolism. In this study, we aimed to define a metabolic profile of the segregated obesity-associated gut dysbiosis risk factor. The study of the metabolome, in an obesity-associated gut dysbiosis model, provides a relevant way for the discrimination on the different biomarkers in the obesity onset. Thus, we developed a model of this obesity risk factors through the transference of gut microbiota from obese to non-obese male Wistar rats and performed a subsequent metabolic analysis in the receptor rats. Our results showed alterations in the lipid metabolism in plasma and in the phenylalanine metabolism in urine. In consequence, we have identified metabolic changes characterized by: (1) an increase in DG:34:2 in plasma, a decrease in hippurate, (2) an increase in 3-HPPA, and (3) an increase in o-coumaric acid. Hereby, we propose these metabolites as a metabolic profile associated to a segregated dysbiosis state related to obesity disease

Long-term supplementation with a low dose of proanthocyanidins normalized liver miR-33a and miR-122 levels in high-fat diet-induced obese rats

Deregulation of miR-33 and miR-122, as major regulators of lipid metabolism in liver, has been related to obesity and metabolic syndrome. Proanthocyanidins repress these microRNAs in healthy animals. Hence, we hypothesized that long-term consumption of dietary proanthocyanidins can normalize the expression of miR-33a and miR-122. Therefore, the objective of this work was to determine whether the long-term consumption of proanthocyanidins could effectively normalize the expression of miR-33a and miR-122 in rats made obese by a high-fat diet and to determine the effective dose. Rats were maintained on the high-fat diet with or without supplementation with a grape seed proanthocyanidin extract at low, medium, or high dose in relation to human consumption. Results show that 3 weeks of supplementation with grape seed proanthocyanidin extract normalized the overexpression of miR-33a and miR-122 in obese rats' liver for all doses studied, with no dose-dependent outcome, and also reduced the levels of plasma and liver lipids in a dose-dependent manner. In conclusion, a low sustained dose of proanthocyanidins, lower than the estimated mean intake for a European population, is enough to normalize miR-33a and miR-122 levels in the livers of obese rats. Therefore, a proanthocyanidin-rich diet during obesity can improve some of the metabolic syndrome symptoms at least at the molecular level. © 2015 Elsevier Inc

Alterations in Metabolome and Microbiome Associated with an Early Stress Stage in Male Wistar Rats: A Multi-Omics Approach

Stress disorders have dramatically increased in recent decades becoming the most prevalent psychiatric disorder in the United States and Europe. However, the diagnosis of stress disorders is currently based on symptom checklist and psychological questionnaires, thus making the identification of candidate biomarkers necessary to gain better insights into this pathology and its related metabolic alterations. Regarding the identification of potential biomarkers, omic profiling and metabolic footprint arise as promising approaches to recognize early biochemical changes in such disease and provide opportunities for the development of integrative candidate biomarkers. Here, we studied plasma and urine metabolites together with metagenomics in a 3 days Chronic Unpredictable Mild Stress (3d CUMS) animal approach that aims to focus on the early stress period of a well-established depression model. The multi-omics integration showed a profile composed by a signature of eight plasma metabolites, six urine metabolites and five microbes. Specifically, threonic acid, malic acid, alpha-ketoglutarate, succinic acid and cholesterol were proposed as key metabolites that could serve as key potential biomarkers in plasma metabolome of early stages of stress. Such findings targeted the threonic acid metabolism and the tricarboxylic acid (TCA) cycle as important pathways in early stress. Additionally, an increase in opportunistic microbes as virus of the Herpesvirales was observed in the microbiota as an effect of the primary stress stages. Our results provide an experimental biochemical characterization of the early stage of CUMS accompanied by a subsequent omic profiling and a metabolic footprinting that provide potential candidate biomarkers

Liver srebp2 and miR-33a and their target mRNA levels.

<p>Experimental details and symbols as in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0069817#pone-0069817-g001" target="_blank">Figure 1</a>.</p

Liver miR-122 and their target mRNA levels.

<p>Rats were fed a STD (STD group) or a STD plus CD for 10 weeks. After 10 weeks, rats fed a STD plus CD were orally treated with 25 mg GSPE/kg bw (CD-GSPE group), 515 mg ω-3 PUFAs/kg bw (CD- DHA-OR), 25 mg GSPE and 515 mg ω-3 PUFAs/kg bw (CD-GSPE- DHA-OR group) or vehicle (CD control group) for 3 weeks simultaneously with the CD. Each value is the mean ± s.e.m. of seven rats. Letters denotes a significant difference between groups (p<0.05; One-way ANOVA).</p