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Wu HX, Lin X, Cheng CL, Jiang HL, Iqbal J, Liu J, Zhou HD. Fat distribution measurements by chemical shift-encoded transition region extraction predict the risk of hyperglycaemia, dyslipidaemia and metabolic syndrome in mice. NMR Biomed 2023; 36:e4985. [PMID: 37283179 DOI: 10.1002/nbm.4985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Revised: 04/27/2023] [Accepted: 05/16/2023] [Indexed: 06/08/2023]
Abstract
Metabolically healthy or unhealthy obesity is closely related to metabolic syndrome (MetS). To validate a more accurate diagnostic method for obesity that reflects the risk of metabolic disorders in a pre-clinical mouse model, C57BL/6J mice were fed high-sucrose-high-fat and chow diets for 12 weeks to induce obesity. MRI was performed and analysed by chemical shift-encoded fat-water separation based on the transition region extraction method. Abdominal fat was divided into upper and lower abdominal regions at the horizontal lower border of the liver. Blood samples were collected, and the glucose level, lipid profile, liver function, HbA1c and insulin were tested. k-means clustering and stepwise logistic regression were applied to validate the diagnosis of hyperglycaemia, dyslipidaemia and MetS, and to ascertain the predictive effect of MRI-derived parameters to the metabolic disorders. Pearson or Spearman correlation was used to assess the relationship between MRI-derived parameters and metabolic traits. The receiver-operating characteristic curve was used to evaluate the diagnostic effect of each logistic regression model. A two-sided p value less than 0.05 was considered to indicate statistical significance for all tests. We made the precise diagnosis of obesity, dyslipidaemia, hyperglycaemia and MetS in mice. In all, 14 mice could be diagnosed as having MetS, and the levels of body weight, HbA1c, triglyceride, total cholesterol and low-density lipoprotein cholesterol were significantly higher than in the normal group. Upper abdominal fat better predicted dyslipidaemia (odds ratio, OR = 2.673; area under the receiver-operating characteristic curve, AUCROC = 0.9153) and hyperglycaemia (OR = 2.456; AUCROC = 0.9454), and the abdominal visceral adipose tissue (VAT) was better for predicting MetS risk (OR = 1.187; AUCROC = 0.9619). We identified the predictive effect of fat volume and distribution in dyslipidaemia, hyperglycaemia and MetS. The upper abdominal fat played a better predictive role for the risk of dyslipidaemia and hyperglycaemia, and the abdominal VAT played a better predictive role for the risk of MetS.
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Affiliation(s)
- Hui-Xuan Wu
- National Clinical Research Center for Metabolic Diseases, Hunan Provincial Key Laboratory for Metabolic Bone Diseases, and Department of Metabolism and Endocrinology, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Xiao Lin
- Clinical Research Center for Medical Imaging in Hunan Province, Department of Radiology Quality Control Center in Hunan Province, Department of Radiology, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Chuan-Li Cheng
- Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China
| | - Hong-Li Jiang
- National Clinical Research Center for Metabolic Diseases, Hunan Provincial Key Laboratory for Metabolic Bone Diseases, and Department of Metabolism and Endocrinology, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Junaid Iqbal
- National Clinical Research Center for Metabolic Diseases, Hunan Provincial Key Laboratory for Metabolic Bone Diseases, and Department of Metabolism and Endocrinology, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Jun Liu
- Clinical Research Center for Medical Imaging in Hunan Province, Department of Radiology Quality Control Center in Hunan Province, Department of Radiology, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
| | - Hou-De Zhou
- National Clinical Research Center for Metabolic Diseases, Hunan Provincial Key Laboratory for Metabolic Bone Diseases, and Department of Metabolism and Endocrinology, The Second Xiangya Hospital of Central South University, Changsha, Hunan, China
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Emin S, Oei EHG, Englund M, Peterson P. Imaging‐based assessment of fatty acid composition in human bone marrow adipose tissue at 7 T: Method comparison and in vivo feasibility. Magn Reson Med 2023; 90:240-249. [PMID: 37119515 PMCID: PMC7614489 DOI: 10.1002/mrm.29623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 01/30/2023] [Accepted: 02/09/2023] [Indexed: 03/03/2023]
Abstract
PURPOSE To demonstrate the feasibility and accuracy of chemical shift-encoded imaging of the fatty acid composition (FAC) of human bone marrow adipose tissue at 7 T, and to determine suitable image-acquisition parameters using simulations. METHODS The noise performance of FAC estimation was investigated using simulations with a range of inter-echo time, and accuracy was assessed using a phantom experiment. Furthermore, one knee of 8 knee-healthy subjects (ages 35-54 years) was imaged, and the fractions of saturated fatty acids (SFA) and polyunsaturated fatty acids (PUFA) were mapped. Values were compared between reconstruction methods, and between anatomical regions. RESULTS Based on simulations, ΔTE = 0.6 ms was chosen. The phantom experiment demonstrated high accuracy of especially SFA using a constrained reconstruction model (slope = 1.1, average bias = -0.2%). The lowest accuracy was seen for PUFA using a free model (slope = 2.0, average bias = 9.0%). For in vivo images, the constrained model resulted in lower intersubject variation compared with the free model (e.g., in the femoral shaft, the SFA percent-point range was within 1.0% [vs. 3.0%]). Furthermore, significant regional FAC differences were detected. For example, using the constrained approach, the femoral SFA in the medial condyle was lower compared with the shaft (median [range]: 27.9% [27.1%, 28.4%] vs. 32.5% [31.8%, 32.8%]). CONCLUSION Bone marrow adipose tissue FAC quantification using chemical-shift encoding is feasible at 7 T. Both the noise performance and accuracy of the technique are superior using a constrained signal model.
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Affiliation(s)
- Sevgi Emin
- Medical Radiation Physics, Department of Translational Medicine Lund University Malmö Sweden
| | - Edwin H. G. Oei
- Department of Radiology & Nuclear Medicine Erasmus MC, University Medical Center Rotterdam The Netherlands
| | - Martin Englund
- Clinical Epidemiology Unit, Orthopedics, Department of Clinical Sciences Lund Lund University Lund Sweden
| | - Pernilla Peterson
- Medical Radiation Physics, Department of Translational Medicine Lund University Malmö Sweden
- Imaging and Physiology Skåne University Hospital Lund Sweden
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Shah SA, Echols JT, Sun C, Wolf MJ, Epstein FH. Accelerated fatty acid composition MRI of epicardial adipose tissue: Development and application to eplerenone treatment in a mouse model of obesity-induced coronary microvascular disease. Magn Reson Med 2022; 88:1734-1747. [PMID: 35726367 PMCID: PMC9339514 DOI: 10.1002/mrm.29348] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 04/23/2022] [Accepted: 05/16/2022] [Indexed: 01/10/2023]
Abstract
Purpose To develop an accelerated MRI method to quantify the epicardial adipose tissue (EAT) fatty acid composition (FAC) and test the hypothesis that eplerenone (EPL) shifts the EAT FAC toward unsaturation in obese mice. Methods Undersampled multi‐echo gradient echo imaging employing a dictionary‐based compressed‐sensing reconstruction and iterative decomposition with echo asymmetry and least‐squares–based mapping (IDEAL) was developed, validated, and used to study EAT in obese mice scanned at 7T. Fully sampled and rate 2, 2.5, 3, and 3.5 undersampled image data were acquired, reconstructed, and assessed using RMSE and structural similarity (SSIM). Two groups of mice were studied: untreated (control, n = 10) and EPL‐treated (n = 10) mice fed a high‐fat high‐sucrose diet. MRI included imaging of EAT FAC, EAT volume, and myocardial perfusion reserve. Results Rate 3 acceleration provided RMSE <5% and structural similarity >0.85 for FAC MRI. After 6 weeks of diet, EPL‐treated compared to untreated mice had a reduced EAT saturated fatty acid fraction (0.27 ± 0.09 vs. 0.39 ± 0.07, P < 0.05) and increased EAT unsaturation degree (4.37 ± 0.32 vs. 3.69 ± 0.58, P < 0.05). Also, EAT volume in EPL‐treated compared to untreated mice was reduced (8.1 ± 0.6 mg vs. 11.4 ± 0.7 mg, P < 0.01), and myocardial perfusion reserve was improved (1.83 ± 0.15 vs. 1.61 ± 0.17, P < 0.05). Conclusion Rate 3 accelerated FAC MRI enabled accurate quantification of EAT FAC in mice. EPL treatment shifted the EAT FAC toward increased unsaturation and was associated with improvement of coronary microvascular function. Click here for author‐reader discussions
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Affiliation(s)
- Soham A Shah
- Biomedical Engineering, University of Virginia, Charlottesville, VA
| | - John T Echols
- Biomedical Engineering, University of Virginia, Charlottesville, VA
| | - Changyu Sun
- Biomedical Engineering, University of Virginia, Charlottesville, VA.,Biomedical, Biological & Chemical Engineering, University of Missouri, Columbia, MO.,Radiolgy, University of Missouri, Columbia, MO
| | - Matthew J Wolf
- Cardiovascular Medicine, University of Virginia, Charlottesville, VA
| | - Frederick H Epstein
- Biomedical Engineering, University of Virginia, Charlottesville, VA.,Radiology, University of Virginia, Charlottesville, VA
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Beekman KM, Regenboog M, Nederveen AJ, Bravenboer N, den Heijer M, Bisschop PH, Hollak CE, Akkerman EM, Maas M. Gender- and Age-Associated Differences in Bone Marrow Adipose Tissue and Bone Marrow Fat Unsaturation Throughout the Skeleton, Quantified Using Chemical Shift Encoding-Based Water-Fat MRI. Front Endocrinol (Lausanne) 2022; 13:815835. [PMID: 35574007 PMCID: PMC9094426 DOI: 10.3389/fendo.2022.815835] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Accepted: 03/17/2022] [Indexed: 01/17/2023] Open
Abstract
Bone marrow adipose tissue (BMAT) is a dynamic tissue which is associated with osteoporosis, bone metastasis, and primary bone tumors. The aim of this study is to determine region-specific variations and age- and gender-specific differences in BMAT and BMAT composition in healthy subjects. In this cross-sectional study, we included 40 healthy subjects (26 male: mean age 49 years, range 22-75 years; 14 female: mean age 50 years, range 29-71) and determined the bone marrow signal fat fraction and bone marrow unsaturation in the spine (C3-L5), pelvis, femora, and tibiae using chemical shift encoding-based water-fat imaging (WFI) with multiple gradient echoes (mGRE). Regions of interest covered the individual vertebral bodies, pelvis and proximal epimetaphysis, diaphysis, and distal epimetaphysis of the femur and tibia. The spinal fat fraction increased from cervical to lumbar vertebral bodies (mean fat fraction ( ± SD or (IQR): cervical spine 0.37 ± 0.1; thoracic spine 0.41 ± 0.08. lumbar spine 0.46 ± 0.01; p < 0.001). The femoral fat fraction increased from proximal to distal (proximal 0.78 ± 0.09; diaphysis 0.86 (0.15); distal 0.93 ± 0.02; p < 0.001), while within the tibia the fat fraction decreased from proximal to distal (proximal 0.92 ± 0.01; diaphysis 0.91 (0.02); distal 0.90 ± 0.01; p < 0.001). In female subjects, age was associated with fat fraction in the spine, pelvis, and proximal femur (ρ = 0.88 p < 0.001; ρ = 0.87 p < 0.001; ρ = 0.63 p = 0.02; ρ = 0.74 p = 0.002, respectively), while in male subjects age was only associated with spinal fat fraction (ρ = 0.40 p = 0.04). Fat fraction and unsaturation were negatively associated within the spine (r = -0.40 p = 0.01), while in the extremities fat fraction and unsaturation were positively associated (distal femur: r = 0.42 p = 0.01; proximal tibia: r = 0.47, p = 0.002; distal tibia: r = 0.35 p = 0.03), both independent of age and gender. In conclusion, we confirm the distinct, age- and gender-dependent, distribution of BMAT throughout the human skeleton and we show that, contradicting previous animal studies, bone marrow unsaturation in human subjects is highest within the axial skeleton compared to the appendicular skeleton. Furthermore, we show that BMAT unsaturation was negatively correlated with BMAT within the spine, while in the appendicular skeleton, BMAT and BMAT unsaturation were positively associated.
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Affiliation(s)
- Kerensa M. Beekman
- Department of Radiology and Nuclear Medicine, Amsterdam University Medical Centers, Amsterdam Movement Sciences, University of Amsterdam, Amsterdam, Netherlands
- Department of Endocrinology, Amsterdam University Medical Centers, Amsterdam Movement Sciences, Vrije Universiteit University, Amsterdam, Netherlands
| | - Martine Regenboog
- Department of Radiology and Nuclear Medicine, Amsterdam University Medical Centers, Amsterdam Movement Sciences, University of Amsterdam, Amsterdam, Netherlands
- Department of Endocrinology and Metabolism, Amsterdam University Medical Centers, Amsterdam Movement Sciences, University of Amsterdam, Amsterdam, Netherlands
| | - Aart J. Nederveen
- Department of Radiology and Nuclear Medicine, Amsterdam University Medical Centers, Amsterdam Movement Sciences, University of Amsterdam, Amsterdam, Netherlands
| | - Nathalie Bravenboer
- Department of Clinical Chemistry, Research Laboratory Bone and Calcium Metabolism, Amsterdam University Medical Centers, Amsterdam Movement Sciences, Vrije Universiteit University, Amsterdam, Netherlands
- Department of Internal Medicine, Leiden University Medical Center, Leiden, Netherlands
| | - Martin den Heijer
- Department of Endocrinology, Amsterdam University Medical Centers, Amsterdam Movement Sciences, Vrije Universiteit University, Amsterdam, Netherlands
| | - Peter H. Bisschop
- Department of Endocrinology and Metabolism, Amsterdam University Medical Centers, Amsterdam Movement Sciences, University of Amsterdam, Amsterdam, Netherlands
| | - Carla E. Hollak
- Department of Endocrinology and Metabolism, Amsterdam University Medical Centers, Amsterdam Movement Sciences, University of Amsterdam, Amsterdam, Netherlands
| | - Erik M. Akkerman
- Department of Radiology and Nuclear Medicine, Amsterdam University Medical Centers, Amsterdam Movement Sciences, University of Amsterdam, Amsterdam, Netherlands
| | - Mario Maas
- Department of Radiology and Nuclear Medicine, Amsterdam University Medical Centers, Amsterdam Movement Sciences, University of Amsterdam, Amsterdam, Netherlands
- *Correspondence: Mario Maas,
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Fritz V, Martirosian P, Machann J, Daniels R, Schick F. A comparison of emulsifiers for the formation of oil-in-water emulsions: stability of the emulsions within 9 h after production and MR signal properties. MAGMA 2021; 35:401-410. [PMID: 34698962 PMCID: PMC9188495 DOI: 10.1007/s10334-021-00970-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 10/12/2021] [Accepted: 10/13/2021] [Indexed: 11/21/2022]
Abstract
Objective To provide a basis for the selection of suitable emulsifiers in oil-in-water emulsions used as tissue analogs for MRI experiments. Three different emulsifiers were investigated with regard to their ability to stabilize tissue-like oil-in-water emulsions. Furthermore, MR signal properties of the emulsifiers themselves and influences on relaxation times and ADC values of the aqueous phase were investigated. Materials and methods Polysorbate 60, sodium dodecyl sulfate (SDS) and soy lecithin were used as emulsifiers. MR characteristics of emulsifiers were assessed in aqueous solutions and their function as a stabilizer was examined in oil-in-water emulsions of varying fat content (10, 20, 30, 40, 50%). Stability and homogeneity of the oil-in-water emulsions were evaluated with a delay of 3 h and 9 h after preparation using T1 mapping and visual control. Signal properties of the emulsifiers were investigated by 1H-MRS in aqueous emulsifier solutions. Relaxometry and diffusion weighted MRI (DWI) were performed to investigate the effect of various emulsifier concentrations on relaxation times (T1 and T2) and ADC values of aqueous solutions. Results Emulsions stabilized by polysorbate 60 or soy lecithin were stable and homogeneous across all tested fat fractions. In contrast, emulsions with SDS showed a significantly lower stability and homogeneity. Recorded T1 maps revealed marked creaming of oil droplets in almost all of the emulsions with SDS. The spectral analysis showed several additional signals for polysorbate and SDS. However, lecithin remained invisible in 1H-MRS. Relaxometry and DWI revealed different influences of the emulsifiers on water: Polysorbate and SDS showed only minor effects on relaxation times and ADC values of aqueous solutions, whereas lecithin showed a strong decrease in both relaxation times (r1,lecithin = 0.11 wt.%−1 s−1, r2,lecithin = 0.57 wt.%−1 s−1) and ADC value (Δ(ADC)lecithin = − 0.18 × 10–3 mm2/s⋅wt.%) with increasing concentration. Conclusion Lecithin is suggested as the preferred emulsifier of oil-in-water emulsions in MRI as it shows a high stabilizing ability and remains invisible in MRI experiments. In addition, lecithin is suitable as an alternative means of adjusting relaxation times and ADC values of water.
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Affiliation(s)
- Victor Fritz
- Section on Experimental Radiology, Department of Diagnostic and Interventional Radiology, University of Tuebingen, Tuebingen, Germany.
| | - Petros Martirosian
- Section on Experimental Radiology, Department of Diagnostic and Interventional Radiology, University of Tuebingen, Tuebingen, Germany
| | - Jürgen Machann
- Section on Experimental Radiology, Department of Diagnostic and Interventional Radiology, University of Tuebingen, Tuebingen, Germany.,Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Centre Munich at the University of Tuebingen, Tuebingen, Germany.,German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Rolf Daniels
- Institute of Pharmaceutical Technology, University of Tuebingen, Tuebingen, Germany
| | - Fritz Schick
- Section on Experimental Radiology, Department of Diagnostic and Interventional Radiology, University of Tuebingen, Tuebingen, Germany.,Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Centre Munich at the University of Tuebingen, Tuebingen, Germany
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Kořínek R, Pfleger L, Eckstein K, Beiglböck H, Robinson SD, Krebs M, Trattnig S, Starčuk Z, Krššák M. Feasibility of Hepatic Fat Quantification Using Proton Density Fat Fraction by Multi-Echo Chemical-Shift-Encoded MRI at 7T. Front Phys 2021; 9:665562. [PMID: 34849373 PMCID: PMC7612048 DOI: 10.3389/fphy.2021.665562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Fat fraction quantification and assessment of its distribution in the hepatic tissue become more important with the growing epidemic of obesity, and the increasing prevalence of diabetes mellitus type 2 and non-alcoholic fatty liver disease. At 3Tesla, the multi-echo, chemical-shift-encoded magnetic resonance imaging (CSE-MRI)-based acquisition allows the measurement of proton density fat-fraction (PDFF) even in clinical protocols. Further improvements in SNR can be achieved by the use of phased array coils and increased static magnetic field. The purpose of the study is to evaluate the feasibility of PDFF imaging using a multi-echo CSE-MRI technique at ultra-high magnetic field (7Tesla). Thirteen volunteers (M/F) with a broad range of age, body mass index, and hepatic PDFF were measured at 3 and 7T by multi-gradient-echo MRI and single-voxel spectroscopy MRS. All measurements were performed in breath-hold (exhalation); the MRI protocols were optimized for a short measurement time, thus minimizing motion-related problems. 7T data were processed off-line using Matlab® (MRI:multi-gradient-echo) and jMRUI (MRS), respectively. For quantitative validation of the PDFF results, a similar protocol was performed at 3T, including on-line data processing provided by the system manufacturer, and correlation analyses between 7 and 3T data were performed off-line. The multi-echo CSE-MRI measurements at 7T with a phased-array coil configuration and an optimal post-processing yielded liver volume coverage ranging from 30 to 90% for high- and low-BMI subjects, respectively. PDFFs ranged between 1 and 20%. We found significant correlations between 7T MRI and -MRS measurements (R2 ≅ 0.97; p < 0.005), and between MRI-PDFF at 7T and 3T fields (R2 ≅ 0.94; p < 0.005) in the evaluated volumes. Based on the measurements and analyses performed, the multi-echo CSE-MRI method using a 32-channel coil at 7T showed its aptitude for MRI-based quantitation of PDFF in the investigated volumes. The results are the first step toward qMRI of the whole liver at 7T with further improvements in hardware.
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Affiliation(s)
- Radim Kořínek
- Magnetic Resonance group, Institute of Scientific Instruments of the Czech Academy of Sciences, Brno, Czechia
| | - Lorenz Pfleger
- Division of Endocrinology and Metabolism, Department of Medicine III, Medical University of Vienna, Vienna, Austria
| | - Korbinian Eckstein
- Department of Biomedical Imaging and Image-Guided Therapy, High-Field Magnetic Resonance Centre, Medical University of Vienna, Vienna, Austria
| | - Hannes Beiglböck
- Division of Endocrinology and Metabolism, Department of Medicine III, Medical University of Vienna, Vienna, Austria
| | - Simon Daniel Robinson
- Department of Biomedical Imaging and Image-Guided Therapy, High-Field Magnetic Resonance Centre, Medical University of Vienna, Vienna, Austria
| | - Michael Krebs
- Division of Endocrinology and Metabolism, Department of Medicine III, Medical University of Vienna, Vienna, Austria
| | - Siegfried Trattnig
- Department of Biomedical Imaging and Image-Guided Therapy, High-Field Magnetic Resonance Centre, Medical University of Vienna, Vienna, Austria
- Christian Doppler Laboratory for Clinical Molecular Imaging, CD Laboratory for Clinical Molecular MR Imaging (MOLIMA), Medical University of Vienna, Vienna, Austria
| | - Zenon Starčuk
- Magnetic Resonance group, Institute of Scientific Instruments of the Czech Academy of Sciences, Brno, Czechia
| | - Martin Krššák
- Division of Endocrinology and Metabolism, Department of Medicine III, Medical University of Vienna, Vienna, Austria
- Department of Biomedical Imaging and Image-Guided Therapy, High-Field Magnetic Resonance Centre, Medical University of Vienna, Vienna, Austria
- Christian Doppler Laboratory for Clinical Molecular Imaging, CD Laboratory for Clinical Molecular MR Imaging (MOLIMA), Medical University of Vienna, Vienna, Austria
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Peterson P, Trinh L, Månsson S. Quantitative 1 H MRI and MRS of fatty acid composition. Magn Reson Med 2020; 85:49-67. [PMID: 32844500 DOI: 10.1002/mrm.28471] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 07/08/2020] [Accepted: 07/20/2020] [Indexed: 12/22/2022]
Abstract
Adipose tissue as well as other depots of fat (triglycerides) are increasingly being recognized as active contributors to the human function and metabolism. In addition to the fat concentration, also the fatty acid chemical composition (FAC) of the triglyceride molecules may play an important part in diseases such as obesity, insulin resistance, hepatic steatosis, osteoporosis, and cancer. MR spectroscopy and chemical-shift-encoded imaging (CSE-MRI) are established methods for non-invasive quantification of fat concentration in tissue. More recently, similar techniques have been developed for assessment also of the FAC in terms of the number of double bonds, the fraction of saturated, monounsaturated, and polyunsaturated fatty acids, or semi-quantitative unsaturation indices. The number of papers focusing on especially CSE-MRI-based techniques has steadily increased during the past few years, introducing a range of acquisition protocols and reconstruction algorithms. However, a number of potential sources of bias have also been identified. Furthermore, the measures used to characterize the FAC using both MRI and MRS differ, making comparisons between different techniques difficult. The aim of this paper is to review MRS- and MRI-based methods for in vivo quantification of the FAC. We describe the chemical composition of triglycerides and discuss various potential FAC measures. Furthermore, we review acquisition and reconstruction methodology and finally, some existing and potential applications are summarized. We conclude that both MRI and MRS provide feasible non-invasive alternatives to the gold standard gas chromatography for in vivo measurements of the FAC. Although both are associated with gas chromatography, future studies are warranted.
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Affiliation(s)
- Pernilla Peterson
- Medical Radiation Physics, Malmö, Department of Translational Medicine, Lund University, Skåne University Hospital, Malmö, Sweden.,Medical Imaging and Physiology, Skåne University Hospital, Lund, Sweden
| | - Lena Trinh
- Medical Radiation Physics, Malmö, Department of Translational Medicine, Lund University, Skåne University Hospital, Malmö, Sweden
| | - Sven Månsson
- Medical Radiation Physics, Malmö, Department of Translational Medicine, Lund University, Skåne University Hospital, Malmö, Sweden
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Shi Z, Xing H, Qi C, Fang M, Fu J, Zhang X. Chinese tree shrews as a primate experimental animal eligible for the study of alcoholic liver disease: characterization and confirmation by MRI. Exp Anim 2019; 69:110-118. [PMID: 31554748 PMCID: PMC7004808 DOI: 10.1538/expanim.19-0073] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
There has been a lack of suitable fatty liver models and characterization techniques for
histopathological evaluation of alcoholic fatty liver (AFL). This work aimed to exploit an
magnetic resonance imaging (MRI) technique for characterizing an alcohol-induced fatty
liver model established in tree shrews (Tupaia belangeri chinese). The
animals were treated with 15% alcohol for two weeks instead of drinking water to induce
AFL. Blood alanine aminotransferase (ALT), aspartate aminotransferase (AST), alcohol, and
liver malondialdehyde (MDA) concentrations were determined, and the histopathology of the
liver was checked by hematoxylin & eosin (HE) and Oil red O staining on day 0 and on
the 4th, 7th and 14th days after alcohol feeding. MRI was used to trace the
histopathological changes in the liver of tree shrews in real time. Compared with the
control group, the levels of ALT, AST, and MDA significantly increased in the
alcohol-induced group and were positively correlated with the induction time. HE and Oil
red O staining revealed that a moderate fatty lesion occurred in the liver on the 4th day
and that a serious AFL was successfully induced on the 14th day. MRI further confirmed the
formation of AFL. MRI, as noninvasive examination technique, provides an alternative tool
for accurate characterization of AFL in live subjects. It is comparable to HE or Oil red O
staining for histopathological examination, but is more suitable by virtue of its high
flexibility and compliance. The AFL model of tree shrews combined with MRI
characterization can work as a platform for studying fatty liver diseases and medications
for their treatment.
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Affiliation(s)
- Zhihai Shi
- Institute of Animal Husbandry and Veterinary, Henan Academy of Agricultural Sciences, 116 Huayuan Road, Zhengzhou, Henan Province 450008, P.R. China
| | - Huijie Xing
- Institute of Laboratory Animals, Jinan University, 601 West Huangpu Avenue, Guangzhou, Guangdong Province 510632, P.R. China
| | - Chunli Qi
- Institute of Laboratory Animals, Jinan University, 601 West Huangpu Avenue, Guangzhou, Guangdong Province 510632, P.R. China
| | - Meixia Fang
- Institute of Laboratory Animals, Jinan University, 601 West Huangpu Avenue, Guangzhou, Guangdong Province 510632, P.R. China
| | - Jiangnan Fu
- Institute of Laboratory Animals, Jinan University, 601 West Huangpu Avenue, Guangzhou, Guangdong Province 510632, P.R. China
| | - Xingwang Zhang
- Department of Pharmaceutics, School of Pharmacy, Jinan University, 601 West Huangpu Avenue, Guangzhou, Guangdong Province 510632, P.R. China
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Viallon M, Leporq B, Drinda S, Wilhelmi de Toledo F, Galusca B, Ratiney H, Croisille P. Chemical-Shift-Encoded Magnetic Resonance Imaging and Spectroscopy to Reveal Immediate and Long-Term Multi-Organs Composition Changes of a 14-Days Periodic Fasting Intervention: A Technological and Case Report. Front Nutr 2019; 6:5. [PMID: 30881957 PMCID: PMC6407435 DOI: 10.3389/fnut.2019.00005] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Accepted: 01/14/2019] [Indexed: 12/21/2022] Open
Abstract
Objectives: The aim of this study was to investigate the feasibility of measuring the effects of a 14-day Periodic Fasting (PF) intervention (<200 cal) on multi-organs of primary interest (liver, visceral/subcutaneous/bone marrow fat, muscle) using non-invasive advanced magnetic resonance spectroscopic (MRS) and imaging (MRI) methods. Methods: One subject participated in a 14-day PF under daily supervision of nurses and specialized physicians, ingesting a highly reduced intake: 200 Kcal/day coupled with active walking and drinking at least 3 L of liquids/day. The fasting was preceded by a 7-day pre-fasting vegetarian period and followed by 14 days of stepwise reintroduction of food. The longitudinal study collected imaging and biological data before the fast, at peak fasting, and 7 days, 1 month, and 4 months after re-feeding. Body fat mass in the trunk, abdomen, and thigh, liver and muscle mass, were respectively computed using advanced MRI and MRS signal modeling. Fat fraction, MRI relativity index T2* and susceptibility (Chi), as well as Fatty acid composition, were calculated at all-time points. Results: A decrease in body weight (BW: −9.5%), quadriceps muscle volume (−3.2%), Subcutaneous and Visceral Adipose Tissue (SAT −34.4%; VAT −20.8%), liver fat fraction (PDFF = 1.4 vs. 2.6 % at baseline) but increase in Spine Bone Marrow adipose tissue (BMAT) associated with a 10% increase in global adiposity fraction (PDFF: 54.4 vs. 50.9%) was observed. Femoral BMAT showed minimal changes compared to spinal level, with a slight decrease (−3.1%). Interestingly, fatty acid (FA) pattern changes differed depending on the AT locations. In muscle, all lipids increased after fasting, with a greater increase of intramyocellular lipid (IMCL: from 2.7 to 6.3 mmol/kg) after fasting compared to extramyocellular lipid (EMCL: from 6.2 to 9.5 mmol/kg) as well as Carnosine (6.9 to 8.1 mmol/kg). Heterogenous and reverse changes were also observed after re-feeding depending on the organ. Conclusion: These results suggest that investigating the effects of a 14-day PF intervention using advanced MRI and MRS is feasible. Quantitative MR indexes are a crucial adjunct to further understanding the effective changes in multiple crucial organs especially liver, spin, and muscle, differences between adipose tissue composition and the interplay that occurs during periodic fasting.
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Affiliation(s)
- Magalie Viallon
- Université de Lyon, Lyon, France.,Centre Hospitalier Universitaire de Saint-Étienne, Saint-Étienne, France.,Université Jean Monnet, Saint-Étienne, France.,CNRS UMR 5520, INSERM U1206, CREATIS, Saint-Étienne, France.,Institut National des Sciences Appliquées de Lyon, Villeurbanne, France
| | - Benjamin Leporq
- Université de Lyon, Lyon, France.,Université Jean Monnet, Saint-Étienne, France.,CNRS UMR 5520, INSERM U1206, CREATIS, Saint-Étienne, France.,Institut National des Sciences Appliquées de Lyon, Villeurbanne, France
| | - Stephan Drinda
- Klinik St. Katharinental, Diessenhofen, Switzerland.,Buchinger Wilhelmi Clinic, Uberlingen, Germany
| | | | - Bogdan Galusca
- Université de Lyon, Lyon, France.,Centre Hospitalier Universitaire de Saint-Étienne, Saint-Étienne, France.,Eating Disorders, Addictions & Extreme Bodyweight Research Group (TAPE) EA, Saint-Étienne, France
| | - Helene Ratiney
- Université de Lyon, Lyon, France.,Université Jean Monnet, Saint-Étienne, France.,CNRS UMR 5520, INSERM U1206, CREATIS, Saint-Étienne, France.,Institut National des Sciences Appliquées de Lyon, Villeurbanne, France
| | - Pierre Croisille
- Université de Lyon, Lyon, France.,Centre Hospitalier Universitaire de Saint-Étienne, Saint-Étienne, France.,Université Jean Monnet, Saint-Étienne, France.,CNRS UMR 5520, INSERM U1206, CREATIS, Saint-Étienne, France.,Institut National des Sciences Appliquées de Lyon, Villeurbanne, France
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10
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Martel D, Leporq B, Saxena A, Belmont HM, Turyan G, Honig S, Regatte RR, Chang G. 3T chemical shift-encoded MRI: Detection of altered proximal femur marrow adipose tissue composition in glucocorticoid users and validation with magnetic resonance spectroscopy. J Magn Reson Imaging 2018; 50:490-496. [PMID: 30548522 DOI: 10.1002/jmri.26586] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Revised: 11/07/2018] [Accepted: 11/08/2018] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Osteoporosis (OP) results in weak bone and can ultimately lead to fracture. Drugs such as glucocorticoids can also induce OP (glucocorticoid-induced osteoporosis [GIO]). Bone marrow adipose tissue composition and quantity may play a role in OP pathophysiology, but has not been thoroughly studied in GIO compared to primary OP. PURPOSE/HYPOTHESIS Chemical shift-encoded (CSE) MRI allows detection of subregional differences in bone marrow adipose tissue composition and quantity in the proximal femur of GIO compared to OP subjects and has high agreement with the reference standard of magnetic resonance spectroscopy (MRS). STUDY TYPE Prospective. SUBJECTS In all, 18 OP and 13 GIO subjects. FIELDS STRENGTH 3T. SEQUENCE Multiple gradient-echo, stimulated echo acquisition mode (STEAM). ASSESSMENT Subjects underwent CSE-MRI in the proximal femurs, and for each parametric map regions of interest (ROIs) were assessed in the femoral head (fHEAD), femoral neck (fNECK), Ward's triangle (fTRIANGLE), and the greater trochanter (GTROCH). In addition, we compared CSE-MRI against the reference standard of MRS performed in the femoral neck and Ward's triangle. STATISTICAL TESTS Differences between OP/GIO were investigated using the Mann-Whitney nonparametric test. Bland-Altman methodology was used to assess measurement agreement between CSE-MRI and MRS. RESULTS GIO compared with OP subjects demonstrated: decreased monounsaturated fat fraction (MUFA) (-2.1%, P < 0.05) in fHEAD; decreased MUFA (-3.8%, P < 0.05), increased saturated fat fraction (SFA) (5.5%, P < 0.05), and decreased T 2 * (-3.8 msec, P < 0.05) in fNECK; decreased proton density fat fraction (PDFF) (-15.1%, P < 0.05), MUFA (-9.8%, P < 0.05), polyunsaturated fat fraction (PUFA) (-1.8%, P < 0.01), increased SFA (11.6%, P < 0.05), and decreased T 2 * (-5.4 msec, P < 0.05) in fTRIANGLE; and decreased T 2 * (-1.5 msec, P < 0.05) in GTROCH. There was high measurement agreement between MRI and MRS using the Bland-Altman test. DATA CONCLUSION 3T CSE-MRI may allow reliable assessment of subregional bone marrow adipose tissue (bMAT) quantity and composition in the proximal femur in a clinically reasonable scan time. Glucocorticoids may alter the lipid profile of bMAT and potentially result in reduced bone quality. LEVEL OF EVIDENCE 2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;50:490-496.
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Affiliation(s)
- Dimitri Martel
- New York Langone Health, Department of Radiology, New York University School of Medicine, New York, New York, USA
| | - Benjamin Leporq
- Université de Lyon, CREATIS CNRS UMR 5220, Inserm U1206, INSA-Lyon, UCBL Lyon 1, Lyon, France
| | - Amit Saxena
- New York Langone Health, Division of Rheumatology, Hospital for Joint Diseases, New York, New York, USA
| | - H Michael Belmont
- New York Langone Health, Division of Rheumatology, Hospital for Joint Diseases, New York, New York, USA
| | - Gabrielle Turyan
- New York Langone Health, Osteoporosis Center, Hospital for Joint Diseases, New York, New York, USA
| | - Stephen Honig
- New York Langone Health, Osteoporosis Center, Hospital for Joint Diseases, New York, New York, USA
| | - Ravinder R Regatte
- New York Langone Health, Department of Radiology, New York University School of Medicine, New York, New York, USA
| | - Gregory Chang
- New York Langone Health, Department of Radiology, New York University School of Medicine, New York, New York, USA
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11
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Schneider M, Janas G, Lugauer F, Hoppe E, Nickel D, Dale BM, Kiefer B, Maier A, Bashir MR. Accurate fatty acid composition estimation of adipose tissue in the abdomen based on bipolar multi‐echo MRI. Magn Reson Med 2018; 81:2330-2346. [DOI: 10.1002/mrm.27557] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Revised: 08/18/2018] [Accepted: 09/11/2018] [Indexed: 12/13/2022]
Affiliation(s)
- Manuel Schneider
- Pattern Recognition Lab, Department of Computer Science Friedrich‐Alexander‐Universität Erlangen‐Nürnberg Erlangen Germany
| | - Gemini Janas
- Radiology Duke University Medical Center Durham North Carolina
- Center for Advanced Magnetic Resonance Development Duke University Medical Center Durham North Carolina
| | - Felix Lugauer
- Pattern Recognition Lab, Department of Computer Science Friedrich‐Alexander‐Universität Erlangen‐Nürnberg Erlangen Germany
| | - Elisabeth Hoppe
- Pattern Recognition Lab, Department of Computer Science Friedrich‐Alexander‐Universität Erlangen‐Nürnberg Erlangen Germany
| | - Dominik Nickel
- MR Applications Predevelopment Siemens Healthcare GmbH Erlangen Germany
| | - Brian M. Dale
- MR R&D Collaborations Siemens Healthineers Cary North Carolina
| | - Berthold Kiefer
- MR Applications Predevelopment Siemens Healthcare GmbH Erlangen Germany
| | - Andreas Maier
- Pattern Recognition Lab, Department of Computer Science Friedrich‐Alexander‐Universität Erlangen‐Nürnberg Erlangen Germany
| | - Mustafa R. Bashir
- Radiology Duke University Medical Center Durham North Carolina
- Center for Advanced Magnetic Resonance Development Duke University Medical Center Durham North Carolina
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12
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Nemeth A, Segrestin B, Leporq B, Coum A, Gambarota G, Seyssel K, Laville M, Beuf O, Ratiney H. Comparison of MRI-derived vs. traditional estimations of fatty acid composition from MR spectroscopy signals. NMR Biomed 2018; 31:e3991. [PMID: 30040156 DOI: 10.1002/nbm.3991] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 05/29/2018] [Accepted: 06/07/2018] [Indexed: 06/08/2023]
Abstract
INTRODUCTION The composition of fatty acids in the body is gaining increasing interest, and can be followed up noninvasively by quantitative magnetic resonance spectroscopy (MRS). However, current MRS quantification methods have been shown to provide different quantitative results in terms of lipid signals, with possible varying outcomes for a given biological examination. Quantitative magnetic resonance imaging using multigradient echo sequence (MGE-MRI) has recently been added to MRS approaches. In contrast, these methods fit the undersampled magnetic resonance temporal signal with a simplified model function (expressing the triglyceride [TG] spectrum with only three TG parameters), specific implementations and prior knowledge. In this study, an adaptation of an MGE-MRI method to MRS lipid quantification is proposed. METHODS Several versions of the method - with time data fully or undersampled, including or excluding the spectral peak T2 knowledge in the fitting - were compared theoretically and on Monte Carlo studies with a time-domain, peak-fitting approach. Robustness, repeatability and accuracy were also inspected on in vitro oil acquisitions and test-retest in vivo subcutaneous adipose tissue acquisitions, adding results from the reference LCModel method. RESULTS On simulations, the proposed method provided TG parameter estimates with the smallest variability, but with a possible bias, which was mitigated by fitting on undersampled data and considering peak T2 values. For in vitro measurements, estimates for all approaches were correlated with theoretical values and the best concordance was found for the usual MRS method (LCModel and peak fitting). Limited in vivo test-retest variability was found (4.1% for PUFAindx, 0.6% for MUFAindx and 3.6% for SFAindx), as for LCModel (7.6% for PUFAindx, 7.8% for MUFAindx and 3.0% for SFAindx). CONCLUSION This study shows that fitting the three TG parameters directly on MRS data is one valuable solution to circumvent the poor conditioning of the MRS quantification problem.
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Affiliation(s)
- Angeline Nemeth
- Université Lyon, INSA-Lyon, Université Claude Bernard Lyon 1, UJM-Saint Etienne, CNRS, Inserm, CREATIS UMR 5220, U1206, Lyon, France
| | - Bérénice Segrestin
- Centre de Recherche en Nutrition Humaine Rhône-Alpes (CRNH-RA), Centre Hospitalier Lyon Sud, Pierre-Bénite, Lyon, France
| | - Benjamin Leporq
- Université Lyon, INSA-Lyon, Université Claude Bernard Lyon 1, UJM-Saint Etienne, CNRS, Inserm, CREATIS UMR 5220, U1206, Lyon, France
| | - Amandine Coum
- INSERM, UMR 1099, Rennes, France
- Université Rennes 1, LTSI, Rennes, France
| | - Giulio Gambarota
- INSERM, UMR 1099, Rennes, France
- Université Rennes 1, LTSI, Rennes, France
| | - Kevin Seyssel
- Department of Physiology, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Martine Laville
- Centre de Recherche en Nutrition Humaine Rhône-Alpes (CRNH-RA), Centre Hospitalier Lyon Sud, Pierre-Bénite, Lyon, France
| | - Olivier Beuf
- Université Lyon, INSA-Lyon, Université Claude Bernard Lyon 1, UJM-Saint Etienne, CNRS, Inserm, CREATIS UMR 5220, U1206, Lyon, France
| | - Hélène Ratiney
- Université Lyon, INSA-Lyon, Université Claude Bernard Lyon 1, UJM-Saint Etienne, CNRS, Inserm, CREATIS UMR 5220, U1206, Lyon, France
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13
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Corrias G, Krebs S, Eskreis-Winkler S, Ryan D, Zheng J, Capanu M, Saba L, Monti S, Fung M, Reeder S, Mannelli L. MRI liver fat quantification in an oncologic population: the added value of complex chemical shift-encoded MRI. Clin Imaging 2018; 52:193-199. [PMID: 30103108 DOI: 10.1016/j.clinimag.2018.08.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Revised: 07/29/2018] [Accepted: 08/03/2018] [Indexed: 02/06/2023]
Abstract
INTRODUCTION Chemotherapy prolongs the survival of patients with advanced and metastatic tumors. Since the liver plays an active role in the metabolism of chemotherapy agents, hepatic injury is a common adverse effect. The purpose of this study is to compare a novel quantitative chemical shift encoded magnetic resonance imaging (CSE-MRI) method with conventional T1-weighted In and Out of phase (T1 IOP) MR for evaluating the reproducibility of the methods in an oncologic population exposed to chemotherapy. MATERIALS AND METHODS This retrospective study was approved by the institutional review board with a waiver for informed consent. The study included patients who underwent chemotherapy, no suspected liver iron overload, and underwent upper abdomen MRI. Two radiologists independently draw circular ROIsin the liver parenchyma. The fat fraction was calculated from IOP imaging and measured from IDEAL-IQ fat fraction maps. Two different equations were used to estimate fat with IOP sequences. Intra-class correlation coefficient and repeatability coefficient were estimated to evaluate agreement between two readers on iron level and fat fraction measurement. RESULTS CSE-MRI showed a higher reliability in fat quantification compared with both IOP methods, with a substantially higher inter-reader agreement (0.961 vs 0.372). This has important clinical implications. CONCLUSION The novel CSE-MRI method described here provides increased reproducibility and confidence in diagnosing hepatic steatosis in a oncologic clinical setting. IDEAL-IQ has been proved to be more reproducible than conventional IOP imaging.
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Affiliation(s)
- Giuseppe Corrias
- Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA; Department of Radiology, University of Cagliari, Via Università, 40, 09124 Cagliari, CA, Italy
| | - Simone Krebs
- Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA
| | - Sarah Eskreis-Winkler
- Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA
| | - Davinia Ryan
- Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA
| | - Junting Zheng
- Department of Statistics, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA
| | - Marinela Capanu
- Department of Statistics, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA
| | - Luca Saba
- Department of Radiology, University of Cagliari, Via Università, 40, 09124 Cagliari, CA, Italy
| | | | - Maggie Fung
- Global MR Applications and Workflow, GE Healthcare, New York, NY, United States
| | - Scott Reeder
- Department of Radiology, University of Wisconsin-Madison, Madison, WI, USA
| | - Lorenzo Mannelli
- Department of Radiology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA.
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14
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Martel D, Leporq B, Bruno M, Regatte RR, Honig S, Chang G. Chemical shift-encoded MRI for assessment of bone marrow adipose tissue fat composition: Pilot study in premenopausal versus postmenopausal women. Magn Reson Imaging 2018; 53:148-155. [PMID: 30006022 DOI: 10.1016/j.mri.2018.07.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Revised: 07/03/2018] [Accepted: 07/05/2018] [Indexed: 12/27/2022]
Abstract
OBJECT To quantify and compare subregional proximal femur bone marrow fat composition in premenopausal and postmenopausal women using chemical shift-encoded-MRI (CSE-MRI). MATERIALS AND METHODS A multi gradient-echo sequence at 3 T was used to scan both hips of premenopausal (n = 9) and postmenopausal (n = 18) women. Subregional fat composition (saturation, poly-unsaturation, mono-unsaturation) was quantitatively assessed in the femoral head, femoral neck, Ward's triangle, greater trochanter, and proximal shaft in bone marrow adipose tissue and separately within red and yellow marrow adipose tissue. RESULTS Significant differences in fat composition in postmenopausal compared to premenopausal women, which varied depending on the subregion analyzed, were found. Within both whole and yellow marrow adipose tissue, postmenopausal women demonstrated higher saturation (+14.7% to +43.3%), lower mono- (-11.4% to -33%) and polyunsaturation (-52 to -83%) (p < 0.05). Within red marrow adipose tissue, postmenopausal women demonstrated lower fat quantity (-16% to -24%) and decreased polyunsaturation (-80 to -120%) in the femoral neck, greater trochanter, and Ward's triangle (p < 0.05). CONCLUSION CSE-MRI can be used to detect subregional differences in proximal femur marrow adipose tissue composition between pre- and post-menopausal women in clinically feasible scan times.
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Affiliation(s)
- Dimitri Martel
- Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York City, NY, USA.
| | - Benjamin Leporq
- University of Lyon, Laboratoire CREATIS, CNRS UMR 5220, Inserm U1206, INSA-Lyon, UJM Saint-Etienne, UCBL Lyon 1, Lyon, France
| | - Mary Bruno
- Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York City, NY, USA
| | - Ravinder R Regatte
- Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York City, NY, USA
| | - Stephen Honig
- Osteoporosis Center, Hospital for Joint Diseases, New York University School of Medicine, New York City, NY, USA
| | - Gregory Chang
- Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, New York University School of Medicine, New York City, NY, USA
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15
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Simchick G, Yin A, Yin H, Zhao Q. Fat spectral modeling on triglyceride composition quantification using chemical shift encoded magnetic resonance imaging. Magn Reson Imaging 2018; 52:84-93. [PMID: 29928937 DOI: 10.1016/j.mri.2018.06.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Revised: 06/14/2018] [Accepted: 06/17/2018] [Indexed: 12/12/2022]
Abstract
PURPOSE To explore, at a high field strength of 7T, the performance of various fat spectral models on the quantification of triglyceride composition and proton density fat fraction (PDFF) using chemical-shift encoded MRI (CSE-MRI). METHODS MR data was acquired from CSE-MRI experiments for various fatty materials, including oil and butter samples and in vivo brown and white adipose mouse tissues. Triglyceride composition and PDFF were estimated using various a priori 6- or 9-peak fat spectral models. To serve as references, NMR spectroscopy experiments were conducted to obtain material specific fat spectral models and triglyceride composition estimates for the same fatty materials. Results obtained using the spectroscopy derived material specific models were compared to results obtained using various published fat spectral models. RESULTS Using a 6-peak fat spectral model to quantify triglyceride composition may lead to large biases at high field strengths. When using a 9-peak model, triglyceride composition estimations vary greatly depending on the relative amplitudes of the chosen a priori spectral model, while PDFF estimations show small variations across spectral models. Material specific spectroscopy derived spectral models produce estimations that better correlate with NMR spectroscopy estimations in comparison to those obtained using non-material specific models. CONCLUSION At a high field strength of 7T, a material specific 9-peak fat spectral model, opposed to a widely accepted or generic human liver model, is necessary to accurately quantify triglyceride composition when using CSE-MRI estimation methods that assume the spectral model to be known as a priori information. CSE-MRI allows for the quantification of the spatial distribution of triglyceride composition for certain in vivo applications. Additionally, PDFF quantification is shown to be independent of the chosen a priori spectral model, which agrees with previously reported results obtained at lower field strengths (e.g. 3T).
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Affiliation(s)
- Gregory Simchick
- Physics and Astronomy, University of Georgia, Athens, GA, United States; Bio-Imaging Research Center, University of Georgia, Athens, GA, United States
| | - Amelia Yin
- Biochemistry and Molecular Biology, University of Georgia, Athens, GA, United States; Center for Molecular Medicine, University of Georgia, Athens, GA, United States
| | - Hang Yin
- Biochemistry and Molecular Biology, University of Georgia, Athens, GA, United States; Center for Molecular Medicine, University of Georgia, Athens, GA, United States
| | - Qun Zhao
- Physics and Astronomy, University of Georgia, Athens, GA, United States; Bio-Imaging Research Center, University of Georgia, Athens, GA, United States.
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16
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He D, Mustafi D, Fan X, Fernandez S, Markiewicz E, Zamora M, Mueller J, Sachleben JR, Brady MJ, Conzen SD, Karczmar GS. Magnetic resonance spectroscopy detects differential lipid composition in mammary glands on low fat, high animal fat versus high fructose diets. PLoS One 2018; 13:e0190929. [PMID: 29324859 PMCID: PMC5764316 DOI: 10.1371/journal.pone.0190929] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Accepted: 12/24/2017] [Indexed: 11/18/2022] Open
Abstract
The effects of consumption of different diets on the fatty acid composition in the mammary glands of SV40 T-antigen (Tag) transgenic mice, a well-established model of human triple-negative breast cancer, were investigated with magnetic resonance spectroscopy and spectroscopic imaging. Female C3(1) SV40 Tag transgenic mice (n = 12) were divided into three groups at 4 weeks of age: low fat diet (LFD), high animal fat diet (HAFD), and high fructose diet (HFruD). MRI scans of mammary glands were acquired with a 9.4 T scanner after 8 weeks on the diet. 1H spectra were acquired using point resolved spectroscopy (PRESS) from two 1 mm3 boxes on each side of inguinal mammary gland with no cancers, lymph nodes, or lymph ducts. High spectral and spatial resolution (HiSS) images were also acquired from nine 1-mm slices. A combination of Gaussian and Lorentzian functions was used to fit the spectra. The percentages of poly-unsaturated fatty acids (PUFA), mono-unsaturated fatty acids (MUFA), and saturated fatty acids (SFA) were calculated from each fitted spectrum. Water and fat peak height images (maps) were generated from HiSS data. The results showed that HAFD mice had significantly lower PUFA than both LFD (p < 0.001) and HFruD (p < 0.01) mice. The mammary lipid quantity calculated from 1H spectra was much larger in HAFD mice than in LFD (p = 0.03) but similar to HFruD mice (p = 0.10). The average fat signal intensity over the mammary glands calculated from HiSS fat maps was ~60% higher in HAFD mice than in LFD (p = 0.04) mice. The mean or median of calculated parameters for the HFruD mice were between those for LFD and HAFD mice. Therefore, PRESS spectroscopy and HiSS MRI demonstrated water and fat composition changes in mammary glands due to a Western diet, which was low in potassium, high in sodium, animal fat, and simple carbohydrates. Measurements of PUFA with MRI could be used to evaluate cancer risk, improve cancer detection and diagnosis, and guide preventative therapy.
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Affiliation(s)
- Dianning He
- Department of Radiology, The University of Chicago, Chicago, Illinois, United States of America
- Sino-Dutch Biomedical and Information Engineering School, Northeastern University, Shenyang, China
| | - Devkumar Mustafi
- Department of Radiology, The University of Chicago, Chicago, Illinois, United States of America
| | - Xiaobing Fan
- Department of Radiology, The University of Chicago, Chicago, Illinois, United States of America
| | - Sully Fernandez
- Department of Medicine, Section of Adult and Pediatric Endocrinology, Diabetes and Metabolism, The University of Chicago, Chicago, Illinois, United States of America
| | - Erica Markiewicz
- Department of Radiology, The University of Chicago, Chicago, Illinois, United States of America
| | - Marta Zamora
- Department of Radiology, The University of Chicago, Chicago, Illinois, United States of America
| | - Jeffrey Mueller
- Department of Pathology, The University of Chicago, Chicago, Illinois, United States of America
| | - Joseph R. Sachleben
- Biomolecular NMR Core Facility, The University of Chicago, Chicago, Illinois, United States of America
| | - Matthew J. Brady
- Department of Medicine, Section of Adult and Pediatric Endocrinology, Diabetes and Metabolism, The University of Chicago, Chicago, Illinois, United States of America
| | - Suzanne D. Conzen
- Department of Medicine, Hematology/Oncology, Hematology/Oncology, The University of Chicago, Chicago, Illinois, United States of America
| | - Gregory S. Karczmar
- Department of Radiology, The University of Chicago, Chicago, Illinois, United States of America
- * E-mail:
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Cao Q, Xu S, Li S, Chen M, Sun X, Wan Y, Pi L, Ying Z, Ren B. Quantification of Hepatic Lipid Using 7.0T Proton Magnetic Resonance Spectroscopy and Computed Tomography in Mild Alcoholic Steatotic Mice. J Liver 2018; 7. [PMID: 30906674 PMCID: PMC6428077 DOI: 10.4172/2167-0889.1000234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Background: In vivo proton magnetic resonance spectroscopy (1H MRS) has been used to semi-quantify hepatic lipids in preclinical and clinical studies of fatty liver disease. Quantifying absolute amount of liver lipids utilizing 1H MRS and computerized tomography (CT) is essential to accurately interpret hepatic steatosis. Purpose: To establish reliable parameters to convert relative hepatic lipid levels obtained by 1H-MRS and liver volumes by CT to the absolute amount of liver lipids in a mild hepatic steatosis, and to determinate the correlation between these absolute liver lipids with liver triglyceride (TG) and cholesterol (Chol) measured by biochemistry assays. Methods: Mild steatosis was induced in mice by a 3 week ethanol diet containing standard lipids. Evaporated liver water was measured after baking liver tissues and volume of liver was measured using water displacement. 1H MRS semiquantitation of hepatic lipids and CT measurement of liver volume were performed and then used to calculate amount of liver lipids. These data were compared with liver TG and Chol. Results: Percentage of liver water and liver density were persistent in two groups and were used to convert the percentage of liver lipids to liver water by 1H-MRS to the absolute amount of liver lipids per gram of liver or per milliliter of CT volume. Using 1H-MRS and biochemical assays, an increase of liver lipids was confirmed in mild steatosis mice compared to controls (P<0.01). The amounts of imaging detected liver lipids were strongly correlated to liver TG and Chol measured by biochemical assays in mild steatosis mice. Conclusion: 1H MRS and CT liver imaging techniques are able to quantify absolute hepatic lipid levels utilizing relative persistent parameters percentage of liver water and liver density in a preclinical mild steatosis setting.
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Affiliation(s)
- Qi Cao
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Su Xu
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Shujing Li
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, Maryland, USA.,Department of Radiology, The first affiliated Hospital of Hebei Medical University, Shijiazhuang, Hebei province, PR China
| | - Minjie Chen
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Xicui Sun
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Yamin Wan
- Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, Maryland, USA.,Department of Radiology, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan province, PR China
| | - Liya Pi
- Department of Pediatrics in the College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Zhekang Ying
- Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Bin Ren
- Department of Surgery, University of Alabama at Birmingham School of Medicine, Alabama, USA
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Dorez H, Ratiney H, Canaple L, Saint-Jalmes H, Gaillard S, Moussata D, Sablong R, Beuf O. In vivo MRS for the assessment of mouse colon using a dedicated endorectal coil: initial findings. NMR Biomed 2017; 30:e3794. [PMID: 28945298 DOI: 10.1002/nbm.3794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Revised: 07/21/2017] [Accepted: 07/24/2017] [Indexed: 06/07/2023]
Abstract
Inflammatory bowel disease is a common group of inflammation conditions that can affect the colon and the rectum. These pathologies require a careful follow-up of patients to prevent the development of colorectal cancer. Currently, conventional endoscopy is used to depict alterations of the intestinal walls, and biopsies are performed on suspicious lesions for further analysis (histology). MRS enables the in vivo analysis of biochemical content of tissues (i.e. without removing any samples). Combined with dedicated endorectal coils (ERCs), MRS provides new ways of characterizing alterations of tissues. An MRS in vivo protocol was specifically set up on healthy mice and on mice chemically treated to induce colitis. Acquisitions were performed on a 4.7 T system using a linear volume birdcage coil for the transmission of the B1 magnetic field, and a dedicated ERC was used for signal reception. Colon-wall complex, lumen and visceral fat were assessed on healthy and treated mice with voxel sizes ranging from 0.125 μL to 2 μL while keeping acquisition times below 3 min. The acquired spectra show various biochemical contents such as α- and β-methylene but also glycerol backbone and diacyl. Choline was detected in tumoral regions. Visceral fat regions display a high lipid content with no water, whereas colon-wall complex exhibits both high lipid and high water contents. To the best of our knowledge, this is the first time that in vivo MRS using an ERC has been performed in the assessment of colon walls and surrounding structures. It provides keys for the in vivo characterization of small local suspicious lesions and offers complementary solutions to biopsies.
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Affiliation(s)
- Hugo Dorez
- Univ Lyon, INSA-Lyon, Université Lyon 1, UJM-Saint Etienne, CNRS, Inserm, CREATIS UMR 5220, U1206, Lyon, France
| | - Hélène Ratiney
- Univ Lyon, INSA-Lyon, Université Lyon 1, UJM-Saint Etienne, CNRS, Inserm, CREATIS UMR 5220, U1206, Lyon, France
| | - Laurence Canaple
- Institut de Génomique Fonctionnelle de Lyon, Université de Lyon 1, UMR 5242 CNRS, Ecole Normale Supérieure de Lyon, Lyon, France
| | - Hervé Saint-Jalmes
- LTSI, INSERM U642, Université Rennes 1, Rennes, France
- CRLCC, Centre Eugène Marquis, Rennes, France
| | - Sophie Gaillard
- Univ Lyon, INSA-Lyon, Université Lyon 1, UJM-Saint Etienne, CNRS, Inserm, CREATIS UMR 5220, U1206, Lyon, France
| | - Driffa Moussata
- Hôpital Régional Universitaire de Tours-Service hépato-gastroentérologie, Tours, France
| | - Raphaël Sablong
- Univ Lyon, INSA-Lyon, Université Lyon 1, UJM-Saint Etienne, CNRS, Inserm, CREATIS UMR 5220, U1206, Lyon, France
| | - Olivier Beuf
- Univ Lyon, INSA-Lyon, Université Lyon 1, UJM-Saint Etienne, CNRS, Inserm, CREATIS UMR 5220, U1206, Lyon, France
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19
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Leporq B, Lambert SA, Ronot M, Vilgrain V, Van Beers BE. Simultaneous MR quantification of hepatic fat content, fatty acid composition, transverse relaxation time and magnetic susceptibility for the diagnosis of non-alcoholic steatohepatitis. NMR Biomed 2017; 30:e3766. [PMID: 28678410 DOI: 10.1002/nbm.3766] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 05/10/2017] [Accepted: 05/30/2017] [Indexed: 06/07/2023]
Abstract
Non-alcoholic steatohepatitis (NASH) is characterized at histology by steatosis, hepatocyte ballooning and inflammatory infiltrates, with or without fibrosis. Although diamagnetic material in fibrosis and inflammation can be detected with quantitative susceptibility imaging, fatty acid composition changes in NASH relative to simple steatosis have also been reported. Therefore, our aim was to develop a single magnetic resonance (MR) acquisition and post-processing scheme for the diagnosis of steatohepatitis by the simultaneous quantification of hepatic fat content, fatty acid composition, T2 * transverse relaxation time and magnetic susceptibility in patients with non-alcoholic fatty liver disease. MR acquisition was performed at 3.0 T using a three-dimensional, multi-echo, spoiled gradient echo sequence. Phase images were unwrapped to compute the B0 field inhomogeneity (ΔB0 ) map. The ΔB0 -demodulated real part images were used for fat-water separation, T2 * and fatty acid composition quantification. The external and internal fields were separated with the projection onto dipole field method. Susceptibility maps were obtained after dipole inversion from the internal field map with single-orientation Bayesian regularization including spatial priors. Method validation was performed in 32 patients with biopsy-proven, non-alcoholic fatty liver disease from which 12 had simple steatosis and 20 NASH. Liver fat fraction and T2 * did not change significantly between patients with simple steatosis and NASH. In contrast, the saturated fatty acid fraction increased in patients with NASH relative to patients with simple steatosis (48 ± 2% versus 44 ± 4%; p < 0.05) and the magnetic susceptibility decreased (-0.30 ± 0.27 ppm versus 0.10 ± 0.14 ppm; p < 0.001). The area under the receiver operating characteristic curve for magnetic susceptibility as NASH marker was 0.91 (95% CI: 0.79-1.0). Simultaneous MR quantification of fat content, fatty acid composition, T2 * and magnetic susceptibility is feasible in the liver. Our preliminary results suggest that quantitative susceptibility imaging has a high diagnostic performance for the diagnosis of NASH.
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Affiliation(s)
- B Leporq
- Laboratory of Imaging Biomarkers, Center of Research on Inflammation, UMR 1149 Inserm, University Paris Diderot, Sorbonne Paris Cité, Paris, France
- Centre de Recherche en Acquisition et Traitement de l'Image pour la Santé, CNRS UMR 5220, Inserm U1209, UCBL Lyon 1, INSA-Lyon, Université de Lyon, France
| | - S A Lambert
- Centre de Recherche en Acquisition et Traitement de l'Image pour la Santé, CNRS UMR 5220, Inserm U1209, UCBL Lyon 1, INSA-Lyon, Université de Lyon, France
| | - M Ronot
- Laboratory of Imaging Biomarkers, Center of Research on Inflammation, UMR 1149 Inserm, University Paris Diderot, Sorbonne Paris Cité, Paris, France
- Department of Radiology, Beaujon University Hospital Paris Nord, Clichy, France
| | - V Vilgrain
- Laboratory of Imaging Biomarkers, Center of Research on Inflammation, UMR 1149 Inserm, University Paris Diderot, Sorbonne Paris Cité, Paris, France
- Department of Radiology, Beaujon University Hospital Paris Nord, Clichy, France
| | - B E Van Beers
- Laboratory of Imaging Biomarkers, Center of Research on Inflammation, UMR 1149 Inserm, University Paris Diderot, Sorbonne Paris Cité, Paris, France
- Department of Radiology, Beaujon University Hospital Paris Nord, Clichy, France
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Cauchy F, Mebarki M, Leporq B, Laouirem S, Albuquerque M, Lambert S, Bourgoin P, Soubrane O, Van Beers BE, Faivre S, Bedossa P, Paradis V. Strong antineoplastic effects of metformin in preclinical models of liver carcinogenesis. Clin Sci (Lond) 2017; 131:27-36. [PMID: 27803295 DOI: 10.1042/CS20160438] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Revised: 09/30/2016] [Accepted: 10/29/2016] [Indexed: 02/07/2023]
Abstract
Studies suggest that metformin, widely used for treating Type 2 diabetes, possesses innate antineoplastic properties. For metabolic syndrome patients with hepatocellular carcinoma (HCC), metformin may provide antitumoral effects. We evaluated the impact of metformin on tumour growth and visceral fat composition using relevant preclinical models of metabolic syndrome. Studies were performed in three hepatoma cell lines, in HepG2 xenograft mice fed with standard chow (SC) diet, 60% high-fat diet (HFD) or 30% fructose diet (FR), and an ex vivo model of human cultured HCC slices. Visceral fatty acid composition was analysed by magnetic resonance imaging (MRI). Metformin had a dose-dependent inhibitory effect on cell proliferation and apoptosis in vitro through the deregulation of mTOR/AMPK, AKT and extracellular signal regulated kinase (ERK) signalling pathways. Tumour engraftment rates were higher in HFD mice than SC mice (hepatic: 79% compared with 25%, P=0.02) and FR mice (subcutaneous: 86% compared with 50%, P=0.04). Subcutaneous tumour volume was increased in HFD mice (+64% compared with FR and SC, P=0.03). Metformin significantly decreased subcutaneous tumour growth via cell-cycle block and mammalian target of rapamycin (mTOR) pathway inhibition, and also induced hypoxia and decreased angiogenesis. In ex vivo tumour slices, metformin treatment led to increased necrosis, decreased cyclin D1 and increased carbonic anhydrase-9 (CA-9). Metformin caused qualitative changes in visceral fat composition of HFD mice, with decreased proportions of polyunsaturated fatty acids (14.6% ± 2.3% compared with 17.9% ± 3.0%, P=0.04). The potent antitumoral effects of metformin in multiple preclinical models implicating several molecular mechanisms provide a strong rationale for clinical trials including combination studies in HCC patients.
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