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Carpentier AC. Tracers and Imaging of Fatty Acid and Energy Metabolism of Human Adipose Tissues. Physiology (Bethesda) 2024; 39:0. [PMID: 38113392 PMCID: PMC11283904 DOI: 10.1152/physiol.00012.2023] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 11/22/2023] [Accepted: 12/19/2023] [Indexed: 12/21/2023] Open
Abstract
White adipose tissue and brown adipose tissue (WAT and BAT) regulate fatty acid metabolism and control lipid fluxes to other organs. Dysfunction of these key metabolic processes contributes to organ insulin resistance and inflammation leading to chronic diseases such as type 2 diabetes, metabolic dysfunction-associated steatohepatitis, and cardiovascular diseases. Metabolic tracers combined with molecular imaging methods are powerful tools for the investigation of these pathogenic mechanisms. Herein, I review some of the positron emission tomography and magnetic resonance imaging methods combined with stable isotopic metabolic tracers to investigate fatty acid and energy metabolism, focusing on human WAT and BAT metabolism. I will discuss the complementary strengths offered by these methods for human investigations and current gaps in the field.
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Affiliation(s)
- André C Carpentier
- Department of Medicine, Division of Endocrinology, Centre de Recherche du Centre Hospitalier Universitaire de Sherbrooke, Université de Sherbrooke, Sherbrooke, Quebec, Canada
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2
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Del Bo' C, Perna S, Allehdan S, Rafique A, Saad S, AlGhareeb F, Rondanelli M, Tayyem RF, Marino M, Martini D, Riso P. Does the Mediterranean Diet Have Any Effect on Lipid Profile, Central Obesity and Liver Enzymes in Non-Alcoholic Fatty Liver Disease (NAFLD) Subjects? A Systematic Review and Meta-Analysis of Randomized Control Trials. Nutrients 2023; 15:nu15102250. [PMID: 37242133 DOI: 10.3390/nu15102250] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 04/27/2023] [Accepted: 05/05/2023] [Indexed: 05/28/2023] Open
Abstract
The effectiveness of the Mediterranean diet (MD) in non-alcoholic fatty liver disease (NAFLD) subjects has been evaluated in several randomized controlled trials (RCTs). This systematic review and meta-analysis aimed to evaluate the overall effects of MD intervention in a cohort of NAFLD patients targeting specific markers such as central obesity, lipid profile, liver enzymes and fibrosis, and intrahepatic fat (IHF). Google Scholar, PubMed, and Scopus were explored to collect relevant studies from the last 10 years. RCTs with NAFLD subjects were included in this systematic review with a mean intervention duration from 6 weeks to 1 year, and different intervention strategies, mainly including energy restriction MD (normal or low glycaemic index), low-fat MD with increased monounsaturated and polyunsaturated fatty acids, and increased exercise expenditure. The outcomes measured in this meta-analysis were gamma-glutamyl transferase (GGT), alanine aminotransferase (ALT), total cholesterol (TC), waist circumference (WC), and liver fibrosis. Ten randomized controlled trials, which involved a total of 737 adults with NAFLD, were included. According to the results, the MD seems to decrease the liver stiffness (kPa) by -0.42 (CI95% -0.92, 0.09) (p = 0.10) and significantly reduce the TC by -0.46 mg/dl (CI95% -0.55, -0.38) (p = 0.001), while no significant findings were documented for liver enzymes and WC among patients with NAFLD. In conclusion, the MD might reduce indirect and direct outcomes linked with NAFLD severity, such as TC, liver fibrosis, and WC, although it is important to consider the variations across trials. Further RCTs are necessary to corroborate the findings obtained and provide further evidence on the role of the MD in the modulation of other disorders related to NAFLD.
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Affiliation(s)
- Cristian Del Bo'
- Department of Food, Environmental and Nutritional Sciences (DeFENS), Division of Human Nutrition, Università degli Studi di Milano, 20133 Milano, Italy
| | - Simone Perna
- Department of Food, Environmental and Nutritional Sciences (DeFENS), Division of Human Nutrition, Università degli Studi di Milano, 20133 Milano, Italy
| | - Sabika Allehdan
- Department of Biology, College of Science, University of Bahrain, Sakhir Campus, Zallaq P.O. Box 32038, Bahrain
| | - Ayesha Rafique
- Department of Biology, College of Science, University of Bahrain, Sakhir Campus, Zallaq P.O. Box 32038, Bahrain
| | - Sara Saad
- Department of Biology, College of Science, University of Bahrain, Sakhir Campus, Zallaq P.O. Box 32038, Bahrain
| | - Fahad AlGhareeb
- Department of Biology, College of Science, University of Bahrain, Sakhir Campus, Zallaq P.O. Box 32038, Bahrain
| | - Mariangela Rondanelli
- IRCCS Mondino Foundation, 27100 Pavia, Italy
- Unit of Human and Clinical Nutrition, Department of Public Health, Experimental and Forensic Medicine, University of Pavia, 27100 Pavia, Italy
| | - Reema F Tayyem
- Department of Human Nutrition, College of Health Sciences, QU Health, Qatar University, Doha P.O. Box 2713, Qatar
| | - Mirko Marino
- Department of Food, Environmental and Nutritional Sciences (DeFENS), Division of Human Nutrition, Università degli Studi di Milano, 20133 Milano, Italy
| | - Daniela Martini
- Department of Food, Environmental and Nutritional Sciences (DeFENS), Division of Human Nutrition, Università degli Studi di Milano, 20133 Milano, Italy
| | - Patrizia Riso
- Department of Food, Environmental and Nutritional Sciences (DeFENS), Division of Human Nutrition, Università degli Studi di Milano, 20133 Milano, Italy
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Sun P, Wu Z, Lin L, Hu G, Zhang X, Wang J. MR-Nucleomics: The study of pathological cellular processes with multinuclear magnetic resonance spectroscopy and imaging in vivo. NMR IN BIOMEDICINE 2023; 36:e4845. [PMID: 36259659 DOI: 10.1002/nbm.4845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 09/28/2022] [Accepted: 10/08/2022] [Indexed: 06/16/2023]
Abstract
Clinical medicine has experienced a rapid development in recent decades, during which therapies targeting specific cellular signaling pathways, or specific cell surface receptors, have been increasingly adopted. While these developments in clinical medicine call for improved precision in diagnosis and treatment monitoring, modern medical imaging methods are restricted mainly to anatomical imaging, lagging behind the requirements of precision medicine. Although positron emission tomography and single photon emission computed tomography have been used clinically for studies of metabolism, their applications have been limited by the exposure risk to ionizing radiation, the subsequent limitation in repeated and longitudinal studies, and the incapability in assessing downstream metabolism. Magnetic resonance spectroscopy (MRS) or spectroscopic imaging (MRSI) are, in theory, capable of assessing molecular activities in vivo, although they are often limited by sensitivity. Here, we review some recent developments in MRS and MRSI of multiple nuclei that have potential as molecular imaging tools in the clinic.
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Affiliation(s)
- Peng Sun
- Clinical & Technical Support, Philips Healthcare, China
| | - Zhigang Wu
- Clinical & Technical Support, Philips Healthcare, China
| | - Liangjie Lin
- Clinical & Technical Support, Philips Healthcare, China
| | - Geli Hu
- Clinical & Technical Support, Philips Healthcare, China
| | | | - Jiazheng Wang
- Clinical & Technical Support, Philips Healthcare, China
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Non-Invasive Analysis of Human Liver Metabolism by Magnetic Resonance Spectroscopy. Metabolites 2021; 11:metabo11110751. [PMID: 34822409 PMCID: PMC8623827 DOI: 10.3390/metabo11110751] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 10/26/2021] [Accepted: 10/26/2021] [Indexed: 11/16/2022] Open
Abstract
The liver is a key node of whole-body nutrient and fuel metabolism and is also the principal site for detoxification of xenobiotic compounds. As such, hepatic metabolite concentrations and/or turnover rates inform on the status of both hepatic and systemic metabolic diseases as well as the disposition of medications. As a tool to better understand liver metabolism in these settings, in vivo magnetic resonance spectroscopy (MRS) offers a non-invasive means of monitoring hepatic metabolic activity in real time both by direct observation of concentrations and dynamics of specific metabolites as well as by observation of their enrichment by stable isotope tracers. This review summarizes the applications and advances in human liver metabolic studies by in vivo MRS over the past 35 years and discusses future directions and opportunities that will be opened by the development of ultra-high field MR systems and by hyperpolarized stable isotope tracers.
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Roumans KH, Basset Sagarminaga J, Peters HP, Schrauwen P, Schrauwen-Hinderling VB. Liver fat storage pathways: methodologies and dietary effects. Curr Opin Lipidol 2021; 32:9-15. [PMID: 33234776 PMCID: PMC7810416 DOI: 10.1097/mol.0000000000000720] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
PURPOSE OF REVIEW Nonalcoholic fatty liver is the result of an imbalance between lipid storage [from meal, de novo lipogenesis (DNL) and fatty acid (FA) uptake] and disposal (oxidation and VLDL output). Knowledge on the contribution of each of these pathways to liver fat content in humans is essential to develop tailored strategies to prevent and treat nonalcoholic fatty liver. Here, we review the techniques available to study the different storage pathways and review dietary modulation of these pathways. RECENT FINDINGS The type of carbohydrate and fat could be of importance in modulating DNL, as complex carbohydrates and omega-3 FAs have been shown to reduce DNL. No effects were found on the other pathways, however studies investigating this are scarce. SUMMARY Techniques used to assess storage pathways are predominantly stable isotope techniques, which require specific expertise and are costly. Validated biomarkers are often lacking. These methodological limitations also translate into a limited number of studies investigating to what extent storage pathways can be modulated by diet. Further research is needed to elucidate in more detail the impact that fat and carbohydrate type can have on liver fat storage pathways and content.
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Affiliation(s)
- Kay H.M. Roumans
- Department of Nutrition and Movement Sciences, Maastricht University, Maastricht
| | | | | | - Patrick Schrauwen
- Department of Nutrition and Movement Sciences, Maastricht University, Maastricht
| | - Vera B. Schrauwen-Hinderling
- Department of Nutrition and Movement Sciences, Maastricht University, Maastricht
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, Maastricht, The Netherlands
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Schött HF, Konings MCJM, Schrauwen-Hinderling VB, Mensink RP, Plat J. A Validated Method for Quantification of Fatty Acids Incorporated in Human Plasma Phospholipids by Gas Chromatography-Triple Quadrupole Mass Spectrometry. ACS OMEGA 2021; 6:1129-1137. [PMID: 33490772 PMCID: PMC7818123 DOI: 10.1021/acsomega.0c03874] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2020] [Accepted: 11/25/2020] [Indexed: 06/12/2023]
Abstract
Fatty acids (FA) are important mediators of health maintenance and disease risk. Optimal quantification assays of FA in high and low abundance as well the identification of 13C-labeled tracers to monitor FA metabolism are of major interest. The article on hand reports about the development and validation of a gas chromatography (GC)-triple quadrupole mass selective detection (GC-TQMS) method for absolute quantification of FA in human plasma phospholipids (hpPL). The quantification of the calibration solution by GC-flame ionization detection (GC-FID), with the introduction of a correction factor, allows the direct comparison of individual FA concentrations in hpPL by GC-TQMS. Specificity, sensitivity, and reproducibility are achieved by optimized chromatographic separation and employment of GC-TQMS. The inter-method comparison between GC-FID and GC-TQMS concentrations revealed good comparability for 27 FA. A full validation has been performed with linearity over 4 magnitudes, a limit of detection of 0.18-38.3 fmol on column, a recovery of 83.6-109.6%, and intraday and interday precision data meeting the criteria of EMA and FDA guidelines. The method includes the absolute quantification of 58 positional and geometrical (cis/trans) isomeric FA in hpPL in the concentration range of 1-3000 nmol/mL, covering also low abundant positional cis/trans isomers. Results obtained from both methods are highly comparable, and selectivity and sensitivity are improved by using GC-TQMS. Additionally, we show here that calculation of 13C-labeled C16:0 tracer/tracee ratios in hpPL in human isotope enrichment studies is possible.
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Affiliation(s)
- Hans-F. Schött
- Singapore
Lipidomics Incubator (SLING), Department of Biochemistry, Yong Loo
Lin School of Medicine, National University
of Singapore, 117597 Singapore
- Department
of Nutrition and Movement Sciences, Maastricht
University, P.O. Box 616, 6200 MD Maastricht, The Netherlands
| | - Maurice C. J. M. Konings
- Department
of Nutrition and Movement Sciences, Maastricht
University, P.O. Box 616, 6200 MD Maastricht, The Netherlands
| | - Vera B. Schrauwen-Hinderling
- Department
of Nutrition and Movement Sciences, Maastricht
University, P.O. Box 616, 6200 MD Maastricht, The Netherlands
| | - Ronald P. Mensink
- Department
of Nutrition and Movement Sciences, Maastricht
University, P.O. Box 616, 6200 MD Maastricht, The Netherlands
| | - Jogchum Plat
- Department
of Nutrition and Movement Sciences, Maastricht
University, P.O. Box 616, 6200 MD Maastricht, The Netherlands
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Veeraiah P, Brouwers K, Wildberger JE, Schrauwen-Hinderling VB, Lindeboom L. Application of a BIlinear Rotation Decoupling (BIRD) filter in combination with J-difference editing for indirect 13 C measurements in the human liver. Magn Reson Med 2020; 84:2911-2917. [PMID: 32618391 PMCID: PMC7540382 DOI: 10.1002/mrm.28394] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 05/20/2020] [Accepted: 06/02/2020] [Indexed: 12/26/2022]
Abstract
PURPOSE Recently, we introduced a quantum coherence based method (ge-HSQC) for indirect 13 C-MRS in the liver to track 13 C-labeled lipids into the hepatic lipid pool in vivo. This approach is more robust in case of respiratory motion, however, inherently leads to a signal loss of 50% when compared with a conventional J-difference editing technique (JDE). Here, we intend to improve the robustness of a regular JDE (STEAM-ACED) with the use of a BIlinear Rotation Decoupling (BIRD) filter to achieve 100% higher signal gain when compared with ge-HSQC. METHODS To determine the efficiency of the BIRD filter 1 H-[13 C] lipid spectra were acquired on 3T from a peanut oil phantom, with three different MR sequences: ge-HSQC, STEAM-ACED, and the BIRD filter together with STEAM-ACED (BIRD-STEAM-ACED). Finally, our proposed method is tested in vivo in five healthy volunteers with varying liver fat content. In these subjects we quantified the 1 H-[13 C]-signal from the hepatic lipid pool and determined 13 C enrichment, which is expected to be 1.1% according to the natural abundance of 13 C. RESULTS The application of the proposed BIRD filter reduces the subtraction artifact of 1 H-[12 C] lipid signal efficiently in JDE experiments, which leads to a signal gain of 100% of 1 H-[13 C]-lipid signals when compared with the ge-HSQC. Phase distortions in vivo were minimal with the use of BIRD compared with STEAM-ACED, which enabled us to robustly quantify the 13 C-enrichment in all five subjects. CONCLUSION The BIRD-STEAM-ACED sequence is an efficient and promising tool for 13 C-tracking experiments in the human liver in vivo.
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Affiliation(s)
- Pandichelvam Veeraiah
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Kim Brouwers
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Joachim E Wildberger
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Vera B Schrauwen-Hinderling
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, Maastricht, The Netherlands.,Department of Nutrition and Movement Sciences, Maastricht University, Maastricht, The Netherlands
| | - Lucas Lindeboom
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, Maastricht, The Netherlands.,Department of Nutrition and Movement Sciences, Maastricht University, Maastricht, The Netherlands
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Resolving Metabolic Heterogeneity in Experimental Models of the Tumor Microenvironment from a Stable Isotope Resolved Metabolomics Perspective. Metabolites 2020; 10:metabo10060249. [PMID: 32549391 PMCID: PMC7345423 DOI: 10.3390/metabo10060249] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 06/02/2020] [Accepted: 06/04/2020] [Indexed: 12/11/2022] Open
Abstract
The tumor microenvironment (TME) comprises complex interactions of multiple cell types that determines cell behavior and metabolism such as nutrient competition and immune suppression. We discuss the various types of heterogeneity that exist in solid tumors, and the complications this invokes for studies of TME. As human subjects and in vivo model systems are complex and difficult to manipulate, simpler 3D model systems that are compatible with flexible experimental control are necessary for studying metabolic regulation in TME. Stable Isotope Resolved Metabolomics (SIRM) is a valuable tool for tracing metabolic networks in complex systems, but at present does not directly address heterogeneous metabolism at the individual cell level. We compare the advantages and disadvantages of different model systems for SIRM experiments, with a focus on lung cancer cells, their interactions with macrophages and T cells, and their response to modulators in the immune microenvironment. We describe the experimental set up, illustrate results from 3D cultures and co-cultures of lung cancer cells with human macrophages, and outline strategies to address the heterogeneous TME.
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9
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van de Weijer T, Schrauwen-Hinderling VB. Application of Magnetic Resonance Spectroscopy in metabolic research. Biochim Biophys Acta Mol Basis Dis 2019; 1865:741-748. [DOI: 10.1016/j.bbadis.2018.09.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2018] [Revised: 09/08/2018] [Accepted: 09/10/2018] [Indexed: 02/08/2023]
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Abstract
Adipose tissue and liver are central tissues in whole body energy metabolism. Their composition, structure, and function can be noninvasively imaged using a variety of measurement techniques that provide a safe alternative to an invasive biopsy. Imaging of adipose tissue is focused on quantitating the distribution of adipose tissue in subcutaneous and intra-abdominal (visceral) adipose tissue depots. Also, detailed subdivisions of adipose tissue can be distinguished with modern imaging techniques. Adipose tissue (or adipocyte) accumulation or infiltration of other organs can also be imaged, with intramuscular adipose tissue a common example. Although liver fat content is now accurately imaged using standard magnetic resonance imaging (MRI) techniques, inflammation and fibrosis are more difficult to determine noninvasively. Liver imaging efforts are therefore concerted on developing accurate imaging markers of liver fibrosis and inflammatory status. Magnetic resonance elastography (MRE) is presently the most reliable imaging technique for measuring liver fibrosis but requires an external device for introduction of shear waves to the liver. Methods using multiparametric diffusion, perfusion, relaxometry, and hepatocyte-specific MRI contrast agents may prove to be more easily implemented by clinicians, provided they reach similar accuracy as MRE. Adipose tissue imaging is experiencing a revolution with renewed interest in characterizing and identifying distinct adipose depots, among them brown adipose tissue. Magnetic resonance spectroscopy provides an interesting yet underutilized way of imaging adipose tissue metabolism through its fatty acid composition. Further studies may shed light on the role of fatty acid composition in different depots and why saturated fat in subcutaneous adipose tissue is a marker of high insulin sensitivity.
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Affiliation(s)
- Jesper Lundbom
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research, Heinrich Heine University, Düsseldorf, Germany
- German Center for Diabetes Research, München-Neuherberg, Düsseldorf, Germany
- HUS Medical Imaging Center, Radiology, Helsinki University Central Hospital, University of Helsinki, Finland
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Abstract
Hepatic steatosis is an underlying feature of nonalcoholic fatty liver disease (NAFLD), which is the most common form of liver disease and is present in up to ∼70% of individuals who are overweight. NAFLD is also associated with hypertriglyceridaemia and low levels of HDL, glucose intolerance, insulin resistance and type 2 diabetes mellitus. Hepatic steatosis is a strong predictor of the development of insulin resistance and often precedes the onset of other known mediators of insulin resistance. This sequence of events suggests that hepatic steatosis has a causal role in the development of insulin resistance in other tissues, such as skeletal muscle. Hepatokines are proteins that are secreted by hepatocytes, and many hepatokines have been linked to the induction of metabolic dysfunction, including fetuin A, fetuin B, retinol-binding protein 4 (RBP4) and selenoprotein P. In this Review, we describe the factors that influence the development of hepatic steatosis, provide evidence of strong links between hepatic steatosis and insulin resistance in non-hepatic tissues, and discuss recent advances in our understanding of how steatosis alters hepatokine secretion to influence metabolic phenotypes through inter-organ communication.
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Affiliation(s)
- Ruth C R Meex
- Monash Biomedicine Discovery Institute, Metabolic Disease and Obesity Program and the Department of Physiology, Monash University, Wellington Road, Clayton, Victoria 3800, Australia
- Department of Human Biology, School of Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University, Universiteitssingel 50, 6229 ER Maastricht, The Netherlands
| | - Matthew J Watt
- Monash Biomedicine Discovery Institute, Metabolic Disease and Obesity Program and the Department of Physiology, Monash University, Wellington Road, Clayton, Victoria 3800, Australia
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Schrauwen-Hinderling VB, Carpentier AC. Molecular imaging of postprandial metabolism. J Appl Physiol (1985) 2017; 124:504-511. [PMID: 28495844 DOI: 10.1152/japplphysiol.00212.2017] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Disordered postprandial metabolism of energy substrates is one of the main defining features of prediabetes and contributes to the development of several chronic diseases associated with obesity, such as type 2 diabetes and cardiovascular diseases. Postprandial energy metabolism has been studied using classical isotopic tracer approaches that are limited by poor access to splanchnic metabolism and highly dynamic and complex exchanges of energy substrates involving multiple organs and systems. Advances in noninvasive molecular imaging modalities, such as PET and MRI/magnetic resonance spectroscopy (MRS), have recently allowed important advances in our understanding of postprandial energy metabolism in humans. The present review describes some of these recent advances, with particular focus on glucose and fatty acid metabolism in the postprandial state, and discusses current gaps in knowledge and new perspectives of application of PET and MRI/MRS for the investigation and treatment of human metabolic diseases.
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Affiliation(s)
- Vera B Schrauwen-Hinderling
- Department of Radiology and Human Biology and Human Movement Sciences, Maastricht University Medical Center , Maastricht , The Netherlands
| | - André C Carpentier
- Department of Medicine, Centre de Recherche du Centre Hospitalier Universitaire de Sherbrooke, Université de Sherbrooke , Sherbrooke, Québec , Canada
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13
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Peters HPF, Schrauwen P, Verhoef P, Byrne CD, Mela DJ, Pfeiffer AFH, Risérus U, Rosendaal FR, Schrauwen-Hinderling V. Liver fat: a relevant target for dietary intervention? Summary of a Unilever workshop. J Nutr Sci 2017; 6:e15. [PMID: 28630692 PMCID: PMC5468740 DOI: 10.1017/jns.2017.13] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Accepted: 03/09/2017] [Indexed: 12/20/2022] Open
Abstract
Currently it is estimated that about 1 billion people globally have non-alcoholic fatty liver disease (NAFLD), a condition in which liver fat exceeds 5 % of liver weight in the absence of significant alcohol intake. Due to the central role of the liver in metabolism, the prevalence of NAFLD is increasing in parallel with the prevalence of obesity, insulin resistance and other risk factors of metabolic diseases. However, the contribution of liver fat to the risk of type 2 diabetes mellitus and CVD, relative to other ectopic fat depots and to other risk markers, is unclear. Various studies have suggested that the accumulation of liver fat can be reduced or prevented via dietary changes. However, the amount of liver fat reduction that would be physiologically relevant, and the timeframes and dose-effect relationships for achieving this through different diet-based approaches, are unclear. Also, it is still uncertain whether the changes in liver fat per se or the associated metabolic changes are relevant. Furthermore, the methods available to measure liver fat, or even individual fatty acids, differ in sensitivity and reliability. The present report summarises key messages of presentations from different experts and related discussions from a workshop intended to capture current views and research gaps relating to the points above.
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Affiliation(s)
- Harry P. F. Peters
- Unilever R&D Vlaardingen, Olivier van Noortlaan 120, Vlaardingen, The Netherlands
| | - Patrick Schrauwen
- Department of Human Biology, NUTRIM School for Nutrition and Translational Research in Metabolism, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Petra Verhoef
- Unilever R&D Vlaardingen, Olivier van Noortlaan 120, Vlaardingen, The Netherlands
| | - Christopher D. Byrne
- Nutrition and Metabolism, Faculty of Medicine, University of Southampton & Southampton National Institute for Health Research Biomedical Research Centre, University Hospital Southampton, Southampton, UK
| | - David J. Mela
- Unilever R&D Vlaardingen, Olivier van Noortlaan 120, Vlaardingen, The Netherlands
| | - Andreas F. H. Pfeiffer
- Department of Endocrinology, Diabetes and Nutrition, Charité Universitätsmedizin Berlin, Campus Benjamin Franklin, Berlin
- Department of Clinical Nutrition, German Institute of Human Nutrition, Potsdam and German Center for Diabetes Research, DZD, Neuherberg, Germany
| | - Ulf Risérus
- Department of Public Health and Caring Sciences, Clinical Nutrition and Metabolism Unit, Uppsala University, Sweden
| | - Frits R. Rosendaal
- Department of Clinical Epidemiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Vera Schrauwen-Hinderling
- Department of Human Biology, NUTRIM School for Nutrition and Translational Research in Metabolism, Maastricht University Medical Center, Maastricht, The Netherlands
- Department of Radiology, NUTRIM School for Nutrition and Translational Research in Metabolism, Maastricht University Medical Center, Maastricht, The Netherlands
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Parks E, Yki-Järvinen H, Hawkins M. Out of the frying pan: dietary saturated fat influences nonalcoholic fatty liver disease. J Clin Invest 2017; 127:454-456. [PMID: 28112684 DOI: 10.1172/jci92407] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Nonalcoholic fatty liver disease (NAFLD) is characterized by excess accumulation of fat in the liver. In some cases, NAFLD is also accompanied by insulin resistance, resulting in metabolic dysfunction. Dietary fat content probably influences both NAFLD and insulin resistance; however, the immediate effects of fat consumption have not been fully explored. In this issue of the JCI, Hernández et al. evaluated hepatic glucose and lipid metabolism in humans and mice following a single oral dose of saturated fat. This one bolus of fat resulted in a measurable increase in insulin resistance, hepatic triglycerides, and gluconeogenesis. In mice, the saturated fat bolus resulted in the induction of several NAFLD-associated genes. Together, the results of this study indicate that saturated fat intake has immediate effects on metabolic function.
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