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Krüger M, Ruppelt A, Kappler B, Van Soest E, Samsom RA, Grinwis GCM, Geijsen N, Helms JB, Stijnen M, Kock LM, Rasponi M, Kooistra HS, Spee B. Normothermic Ex Vivo Liver Platform Using Porcine Slaughterhouse Livers for Disease Modeling. Bioengineering (Basel) 2022; 9:bioengineering9090471. [PMID: 36135018 PMCID: PMC9495507 DOI: 10.3390/bioengineering9090471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Revised: 08/25/2022] [Accepted: 09/07/2022] [Indexed: 11/16/2022] Open
Abstract
Metabolic and toxic liver disorders, such as fatty liver disease (steatosis) and drug-induced liver injury, are highly prevalent and potentially life-threatening. To allow for the study of these disorders from the early stages onward, without using experimental animals, we collected porcine livers in a slaughterhouse and perfused these livers normothermically. With our simplified protocol, the perfused slaughterhouse livers remained viable and functional over five hours of perfusion, as shown by hemodynamics, bile production, indocyanine green clearance, ammonia metabolism, gene expression and histology. As a proof-of-concept to study liver disorders, we show that an infusion of free fatty acids and acetaminophen results in early biochemical signs of liver damage, including reduced functionality. In conclusion, the present platform offers an accessible system to perform research in a functional, relevant large animal model while avoiding using experimental animals. With further improvements to the model, prolonged exposure could make this model a versatile tool for studying liver diseases and potential treatments.
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Affiliation(s)
- Melanie Krüger
- LifeTec Group BV, 5611 ZS Eindhoven, The Netherlands
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, 3584 CT Utrecht, The Netherlands
| | - Alicia Ruppelt
- LifeTec Group BV, 5611 ZS Eindhoven, The Netherlands
- Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, 20133 Milan, Italy
- Correspondence:
| | | | | | - Roos Anne Samsom
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, 3584 CT Utrecht, The Netherlands
| | - Guy C. M. Grinwis
- Veterinary Pathology Diagnostic Centre, Department of Biomedical Health Sciences, Faculty of Veterinary Medicine, Utrecht University, 3508 TD Utrecht, The Netherlands
| | - Niels Geijsen
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, 3584 CT Utrecht, The Netherlands
| | - J. Bernd Helms
- Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, 3584 CL Utrecht, The Netherlands
| | - Marco Stijnen
- LifeTec Group BV, 5611 ZS Eindhoven, The Netherlands
| | - Linda M. Kock
- LifeTec Group BV, 5611 ZS Eindhoven, The Netherlands
- Department of Biomedical Engineering, Eindhoven University of Technology, 5600 MB Eindhoven, The Netherlands
| | - Marco Rasponi
- Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, 20133 Milan, Italy
| | - Hans S. Kooistra
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, 3584 CT Utrecht, The Netherlands
| | - Bart Spee
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, 3584 CT Utrecht, The Netherlands
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Huang S, Blutke A, Feuchtinger A, Klemm U, Zachariah Tom R, Hofmann SM, Stiel AC, Ntziachristos V. Functional multispectral optoacoustic tomography imaging of hepatic steatosis development in mice. EMBO Mol Med 2021; 13:e13490. [PMID: 34411447 PMCID: PMC8422073 DOI: 10.15252/emmm.202013490] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Revised: 07/08/2021] [Accepted: 07/14/2021] [Indexed: 12/14/2022] Open
Abstract
The increasing worldwide prevalence of obesity, fatty liver diseases and the emerging understanding of the important roles lipids play in various other diseases is generating significant interest in lipid research. Lipid visualization in particular can play a critical role in understanding functional relations in lipid metabolism. We investigated the potential of multispectral optoacoustic tomography (MSOT) as a novel modality to non-invasively visualize lipids in laboratory mice around the 930nm spectral range. Using an obesity-induced non-alcoholic fatty liver disease (NAFLD) mouse model, we examined whether MSOT could detect and differentiate different grades of hepatic steatosis and monitor the accumulation of lipids in the liver quantitatively over time, without the use of contrast agents, i.e. in label-free mode. Moreover, we demonstrate the efficacy of using the real-time clearance kinetics of indocyanine green (ICG) in the liver, monitored by MSOT, as a biomarker to evaluate the organ's function and assess the severity of NAFLD. This study establishes MSOT as an efficient imaging tool for lipid visualization in preclinical studies, particularly for the assessment of NAFLD.
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Affiliation(s)
- Shan Huang
- Chair of Biological ImagingSchool of Medicine, Central Institute for Translational Cancer Research (TranslaTUM)Technical University of MunichGermany
- Institute of Biological and Medical ImagingHelmholtz Zentrum München (GmbH)NeuherbergGermany
| | - Andreas Blutke
- Research Unit Analytical PathologyHelmholtz Zentrum München (GmbH)NeuherbergGermany
| | - Annette Feuchtinger
- Research Unit Analytical PathologyHelmholtz Zentrum München (GmbH)NeuherbergGermany
| | - Uwe Klemm
- Chair of Biological ImagingSchool of Medicine, Central Institute for Translational Cancer Research (TranslaTUM)Technical University of MunichGermany
| | - Robby Zachariah Tom
- Institute of Diabetes and Regeneration ResearchHelmholtz Zentrum München (GmbH)NeuherbergGermany
- Medizinische Klinik und Poliklinik IVLudwig‐Maximilians‐Universität MünchenMunichGermany
| | - Susanna M Hofmann
- Institute of Diabetes and Regeneration ResearchHelmholtz Zentrum München (GmbH)NeuherbergGermany
| | - Andre C Stiel
- Chair of Biological ImagingSchool of Medicine, Central Institute for Translational Cancer Research (TranslaTUM)Technical University of MunichGermany
| | - Vasilis Ntziachristos
- Chair of Biological ImagingSchool of Medicine, Central Institute for Translational Cancer Research (TranslaTUM)Technical University of MunichGermany
- Institute of Biological and Medical ImagingHelmholtz Zentrum München (GmbH)NeuherbergGermany
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Paradossi G, Oddo L, Cerroni B, Ben-Harush C, Ariel E, Di Meco F, Ram Z, Grossman R. In Vivo Toxicity Study of Engineered Lipid Microbubbles in Rodents. ACS OMEGA 2019; 4:5526-5533. [PMID: 31497678 PMCID: PMC6715268 DOI: 10.1021/acsomega.8b03161] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Accepted: 01/16/2019] [Indexed: 05/08/2023]
Abstract
Real-time intraoperative imaging for brain tumor surgery is crucial for achieving complete resection. We are developing novel lipid-based microbubbles (MBs), engineered with specific ligands, which are able to interact with the integrins overexpressed in the endothelium of the brain tumor vasculature. These MBs are designed to visualize the tumor and to carry therapeutic molecules into the tumor tissue, preserving the ultrasound acoustic properties of the starting plain lipid MBs. The potential toxicity of this novel technology was assessed in rats by intravenous injections of two doses of plain MBs and MBs engineered for targeting and near-infrared fluorescence visualization at two time-points, 10 min and 7 days, for potential acute and chronic responses in rats [(1) MB, (2) MB-ICG, (3) MB-RGD, and (4) MB-ICG-RGD]. No mortality occurred during the 7-day study period in any of the dosing groups. All animals demonstrated a body weight gain during the study period. Minor, mostly reversible changes in hematological and biochemical analysis were observed in some of the treated animals. All changes were reversible by the 7-day time-point. Histopathology examination in the high-dose animals showed development of foreign body granulomatous inflammation. We concluded that the low-dose tested items appear to be safe. The results allow for proceeding to clinical testing of the product.
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Affiliation(s)
- Gaio Paradossi
- Dipartimento di Scienze e Tecnologie Chimiche, Università degli Studi di Roma Tor Vergata, 00133 Roma, Italy
| | - Letizia Oddo
- Dipartimento di Scienze e Tecnologie Chimiche, Università degli Studi di Roma Tor Vergata, 00133 Roma, Italy
| | - Barbara Cerroni
- Dipartimento di Scienze e Tecnologie Chimiche, Università degli Studi di Roma Tor Vergata, 00133 Roma, Italy
| | - Carmit Ben-Harush
- Department of Neurosurgery,
Tel Aviv Medical Center, Affiliated to the Sackler Faculty of Medicine, Tel-Aviv University, 6997801 Tel-Aviv, Israel
| | - Eti Ariel
- Department of Neurosurgery,
Tel Aviv Medical Center, Affiliated to the Sackler Faculty of Medicine, Tel-Aviv University, 6997801 Tel-Aviv, Israel
| | - Francesco Di Meco
- Neuro-Oncology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, 20133 Milan, Italy
| | - Zvi Ram
- Department of Neurosurgery,
Tel Aviv Medical Center, Affiliated to the Sackler Faculty of Medicine, Tel-Aviv University, 6997801 Tel-Aviv, Israel
| | - Rachel Grossman
- Department of Neurosurgery,
Tel Aviv Medical Center, Affiliated to the Sackler Faculty of Medicine, Tel-Aviv University, 6997801 Tel-Aviv, Israel
- E-mail: . Phone: +972-3-6974273. Fax: +972-3-6974860
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4
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The potential role of vascular alterations and subsequent impaired liver blood flow and hepatic hypoxia in the pathophysiology of non-alcoholic steatohepatitis. Med Hypotheses 2018; 122:188-197. [PMID: 30593409 DOI: 10.1016/j.mehy.2018.11.014] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Accepted: 11/21/2018] [Indexed: 12/12/2022]
Abstract
Non-alcoholic fatty liver disease (NAFLD) covers a spectrum of disease ranging from steatosis to steatohepatitis (NASH) and fibrosis, but the underlying pathophysiological mechanisms remain largely unknown. As there is currently no approved pharmacological therapy and the prevalence of NAFLD keeps increasing, understanding of its pathophysiology is crucial. We hypothesise that vascular alterations in early NAFLD play a role in the progression of the disease by inducing an increased intrahepatic vascular resistance and consequently relative hypoxia in the liver. Evidence of the detrimental effects of hypoxia in NAFLD has already been observed in liver surgery, where the outcomes of steatotic livers after ischaemia-reperfusion are worse than in healthy livers, and in obstructive sleep apnoea, which is an independent risk factor of NAFLD. Moreover, early histological damage in NAFLD is situated in the pericentral zone, which is also the first zone to be affected by a decreased oxygen tension because of the unique hepatic vacsular anatomy that causes the pericentral oxygen tension to be the lowest. Angiogenesis is also a characteristic of NAFLD, driven by hypoxia-induced mechanisms, as demonstrated in both animal models and in humans with NAFLD. Relative hypoxia is most probably induced by impaired blood flow to the liver, caused by increased intrahepatic vascular resistance. An increased intrahepatic vascular resistance early in the development of disease has been convincingly demonstrated in several animal models of NAFLD, whereas an increased portal pressure, a consequence of increased intrahepatic vascular resistance, has been proven in patients with NAFLD. Animal studies demonstrated a decreased intrahepatic effect of vasodilators and an increased reactivity to vasoconstrictors that results in an increased intrahepatic vascular resistance, thus the presence of a functional component. Pharmacological products that target vasoregulation can hence improve the intrahepatic vascular resistance and this might prevent or reverse progression of NAFLD, representing an important therapeutic option to study. Some of the drugs currently under evaluation in clinical trials for NASH have interesting properties related to the hepatic vasculature. Some other interesting drugs have been tested in animal models but further study in patients with NAFLD is warranted. In summary, in this paper we summarise the evidence that leads to the hypothesis that an increased intrahepatic vascular resistance and subsequent parenchymal hypoxia in early NAFLD is an important pathophysiological driving mechanism for the progression of the disease.
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Belotta AF, Teixeira CR, Padovani CR, Rahal SC, Mayer MN, Mamprim MJ. Sonographic Evaluation of Liver Hemodynamic Indices in Overweight and Obese Dogs. J Vet Intern Med 2017; 32:181-187. [PMID: 29280193 PMCID: PMC5787168 DOI: 10.1111/jvim.14883] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Revised: 08/05/2017] [Accepted: 10/18/2017] [Indexed: 02/06/2023] Open
Abstract
Background Hepatic circulatory disturbances have been associated with obesity and fatty liver in humans. In the veterinary literature, however, there is limited information regarding the effects of different body condition scores (BCS) on liver hemodynamic indices in dogs. Objectives To investigate the influence of BCS on liver hemodynamic indices. Animals Fifty‐three client‐owned dogs of various breeds were included. Methods Prospective observational study. Dogs were divided into 3 BCS groups using a 5‐point scale: G1 – 12 ideal dogs, G2 – 21 overweight dogs, G3 – 20 obese dogs. Mean portal velocity (MPV), portal blood flow volume (PBFV), portal congestion index (PCI), hepatic artery resistivity index (HARI), and hepatic vein (HV) spectral wave were obtained by pulsed Doppler sonography. Alkaline phosphatase (ALP), gamma‐glutamyl transferase (GGT), and alanine aminotransferase (ALT) activities were determined. Liver enzymes activities and liver hemodynamic indices were compared among groups. Results Obese dogs had lower MPV, higher percentage of abnormal hepatic vein spectral wave and higher median ALP activity than did ideal dogs (P < 0.05). Overweight and obese dogs had lower PBFV than ideal dogs (P < 0.01). Overweight dogs had higher median GGT activity than ideal dogs (P < 0.05). No difference was observed for PCI, HARI and median ALT activity among the groups. Conclusions and Clinical Importance Obesity was associated with changes in portal vein indices and in HV spectral wave. These changes were accompanied by significant differences in some liver enzymes activities and could be a sign of early liver disease.
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Affiliation(s)
- A F Belotta
- Department of Animal Reproduction and Veterinary Radiology, São Paulo State University "Júlio de Mesquita Filho", Botucatu, SP, Brazil
| | - C R Teixeira
- Department of Veterinary Surgery and Anesthesiology, São Paulo State University "Júlio de Mesquita Filho", Botucatu, SP, Brazil
| | - C R Padovani
- School of Veterinary Medicine and Animal Science, São Paulo State University "Júlio de Mesquita Filho", Botucatu, SP, Brazil.,Department of Biostatistics, Biosciences Institute, São Paulo State University "Júlio de Mesquita Filho", Botucatu, SP, Brazil
| | - S C Rahal
- Department of Veterinary Surgery and Anesthesiology, São Paulo State University "Júlio de Mesquita Filho", Botucatu, SP, Brazil
| | - M N Mayer
- Department of Small Animal Clinical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, SK, Canada
| | - M J Mamprim
- Department of Animal Reproduction and Veterinary Radiology, São Paulo State University "Júlio de Mesquita Filho", Botucatu, SP, Brazil
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Nozaki Y, Fujita K, Wada K, Yoneda M, Shinohara Y, Imajo K, Ogawa Y, Kessoku T, Nakamuta M, Saito S, Masaki N, Nagashima Y, Terauchi Y, Nakajima A. Deficiency of eNOS exacerbates early-stage NAFLD pathogenesis by changing the fat distribution. BMC Gastroenterol 2015; 15:177. [PMID: 26678309 PMCID: PMC4683865 DOI: 10.1186/s12876-015-0409-9] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2015] [Accepted: 12/07/2015] [Indexed: 01/21/2023] Open
Abstract
Background Although many factors and molecules that are closely associated with non-alcoholic fatty liver disease (NAFLD)/non-alcoholic steatohepatitis (NASH) have been reported, the role of endothelial nitric oxide synthase (eNOS)-derived nitric oxide (NO) in the pathogenesis of NAFLD/NASH remains unclear. We therefore investigated the role of eNOS-derived NO in NAFLD pathogenesis using systemic eNOS-knockout mice fed a high-fat diet. Methods eNOS-knockout and wild-type mice were fed a basal diet or a high-fat diet for 12 weeks. Lipid accumulation and inflammation were evaluated in the liver, and various factors that are closely associated with NAFLD/NASH and hepatic tissue blood flow were analyzed. Results Lipid accumulation and inflammation were more extensive in the liver and lipid accumulation was less extensive in the visceral fat tissue in eNOS-knockout mice, compared with wild-type mice, after 12 weeks of being fed a high-fat diet. While systemic insulin resistance was comparable between the eNOS-knockout and wild-type mice fed a high-fat diet, hepatic tissue blood flow was significantly suppressed in the eNOS-knockout mice, compared with the wild-type mice, in mice fed a high-fat diet. The microsomal triglyceride transfer protein activity was down-regulated in eNOS-knockout mice, compared with wild-type mice, in mice fed a high-fat diet. Conclusions A deficiency of eNOS-derived NO may exacerbate the early-stage of NASH pathogenesis by changing the fat distribution in a mouse model via the regulation of hepatic tissue blood flow.
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Affiliation(s)
- Yuichi Nozaki
- Department of Gastroenterology, Yokohama City University Graduate School of Medicine, 3-9 Fuku-ura, Kanazawa-ku, 236-0004, Yokohama, Kanagawa, Japan. .,Department of Gastroenterology, National Center for Global Health and Medicine, 1-21-1, Toyama, Shinjuku-ku, 162-8655, Tokyo, Japan.
| | - Koji Fujita
- Department of Gastroenterology, Yokohama City University Graduate School of Medicine, 3-9 Fuku-ura, Kanazawa-ku, 236-0004, Yokohama, Kanagawa, Japan.
| | - Koichiro Wada
- Department of Pharmacology, Graduate School of Dentistry, Osaka University, 1-8 Yamadaoka, 565-0871, Suita, Osaka, Japan.
| | - Masato Yoneda
- Department of Gastroenterology, Yokohama City University Graduate School of Medicine, 3-9 Fuku-ura, Kanazawa-ku, 236-0004, Yokohama, Kanagawa, Japan.
| | - Yoshiyasu Shinohara
- Department of Gastroenterology, Yokohama City University Graduate School of Medicine, 3-9 Fuku-ura, Kanazawa-ku, 236-0004, Yokohama, Kanagawa, Japan.
| | - Kento Imajo
- Department of Gastroenterology, Yokohama City University Graduate School of Medicine, 3-9 Fuku-ura, Kanazawa-ku, 236-0004, Yokohama, Kanagawa, Japan.
| | - Yuji Ogawa
- Department of Gastroenterology, Yokohama City University Graduate School of Medicine, 3-9 Fuku-ura, Kanazawa-ku, 236-0004, Yokohama, Kanagawa, Japan.
| | - Takaomi Kessoku
- Department of Gastroenterology, Yokohama City University Graduate School of Medicine, 3-9 Fuku-ura, Kanazawa-ku, 236-0004, Yokohama, Kanagawa, Japan.
| | - Makoto Nakamuta
- Department of Gastroenterology, Kyushu Medical Center, National Hospital Organization, 1-8-1, Jigyohama, Chuo-ku, 810-8563, Fukuoka, Japan.
| | - Satoru Saito
- Department of Gastroenterology, Yokohama City University Graduate School of Medicine, 3-9 Fuku-ura, Kanazawa-ku, 236-0004, Yokohama, Kanagawa, Japan.
| | - Naohiko Masaki
- The Research Center for Hepatitis and Immunology, National Center for Global Health and Medicine, 1-7-1, Konodai, 272-8516, Ichikawa, China, Japan.
| | - Yoji Nagashima
- Department of Molecular Pathology, Yokohama City University Graduate School of Medicine, 3-9 Fuku-ura, Kanazawa-ku, 236-0004, Yokohama, Kanagawa, Japan. .,Department of Surgical Pathology, Tokyo Women`s Medical University, 8-1, Kawada-cho, Shinjuku-ku, Tokyo, 162-8666, Japan.
| | - Yasuo Terauchi
- Department of Endocrinology and Metabolism, Yokohama City University Graduate School of Medicine, 3-9 Fuku-ura, Kanazawa-ku, 236-0004, Yokohama, Kanagawa, Japan.
| | - Atsushi Nakajima
- Department of Gastroenterology, Yokohama City University Graduate School of Medicine, 3-9 Fuku-ura, Kanazawa-ku, 236-0004, Yokohama, Kanagawa, Japan.
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Topal NB, Orcan S, Sığırlı D, Orcan G, Eritmen Ü. Effects of fat accumulation in the liver on hemodynamic variables assessed by Doppler ultrasonography. JOURNAL OF CLINICAL ULTRASOUND : JCU 2015; 43:26-33. [PMID: 24867781 DOI: 10.1002/jcu.22157] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Revised: 12/06/2013] [Accepted: 03/13/2014] [Indexed: 06/03/2023]
Abstract
PURPOSE To investigate the effect of various degrees of fatty liver infiltration on hepatic hemodynamics using Doppler ultrasonography. METHODS We included 40 patients with hepatic steatosis and 20 healthy volunteers. Hepatic steatosis was quantified by a chemical shift MRI. Hepatic artery peak systolic and end-diastolic velocity, resistance index (RI) and pulsatility index (PI), hepatic vein RI and PI, portal vein RI, PI, congestion index, and peak maximum velocity were evaluated by Doppler ultrasonography. The hepatic vein waveforms were classified as triphasic, biphasic, or monophasic. Kruskal-Wallis test was performed for comparing more than two groups. If significant differences were found, Mann-Whitney U test with Bonferroni correction was performed for pair-wise comparisons. Pearson &gch;(2) and Fisher's exact tests were used to compare categorical variables. RESULTS According to MRI, 15 patients had mild, 14 patients had moderate, and 11 patients had severe fatty infiltration. Portal vein peak maximum velocity was median: 19.8 (range 12-33.3), 21.1 (8-41.8), 16.6 (10.6-24.9), and 29.2 (14.1-40.4) cm/s. Congestion index was 0.05 (0.02-0.16), 0.07 (0.01-0.17), 0.11 (0.06-0.24), and 0.05 (0.02-0.16). Hepatic artery RI was 0.75 (0.56-1.00), 0.66 (0.52-0.87), 0.83 (0.38-1.00), and 0.76 (0.48-2.76), and PI was 1.83 (0.90-3.13), 1.38 (1.04-2.63), 1.97 (0.86-2.90), and 1.82 (0.70-2.90) (p = .046 and p = .036) in the mild, moderate, severe steatosis, and control groups, respectively. The rate of triphasic hepatic vein waveforms was higher in controls than in patients with severe steatosis. CONCLUSIONS Portal vein flow velocity decreases in severe hepatic steatosis when compared with controls.
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Affiliation(s)
- Naile Bolca Topal
- Uludag University Faculty of Medicine, Department of Radiology, Nilufer/Bursa, Turkey
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Hoekstra LT, de Graaf W, Nibourg GAA, Heger M, Bennink RJ, Stieger B, van Gulik TM. Physiological and biochemical basis of clinical liver function tests: a review. Ann Surg 2013; 257:27-36. [PMID: 22836216 DOI: 10.1097/sla.0b013e31825d5d47] [Citation(s) in RCA: 226] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
OBJECTIVE To review the literature on the most clinically relevant and novel liver function tests used for the assessment of hepatic function before liver surgery. BACKGROUND Postoperative liver failure is the major cause of mortality and morbidity after partial liver resection and develops as a result of insufficient remnant liver function. Therefore, accurate preoperative assessment of the future remnant liver function is mandatory in the selection of candidates for safe partial liver resection. METHODS A MEDLINE search was performed using the key words "liver function tests," "functional studies in the liver," "compromised liver," "physiological basis," and "mechanistic background," with and without Boolean operators. RESULTS Passive liver function tests, including biochemical parameters and clinical grading systems, are not accurate enough in predicting outcome after liver surgery. Dynamic quantitative liver function tests, such as the indocyanine green test and galactose elimination capacity, are more accurate as they measure the elimination process of a substance that is cleared and/or metabolized almost exclusively by the liver. However, these tests only measure global liver function. Nuclear imaging techniques ((99m)Tc-galactosyl serum albumin scintigraphy and (99m)Tc-mebrofenin hepatobiliary scintigraphy) can measure both total and future remnant liver function and potentially identify patients at risk for postresectional liver failure. CONCLUSIONS Because of the complexity of liver function, one single test does not represent overall liver function. In addition to computed tomography volumetry, quantitative liver function tests should be used to determine whether a safe resection can be performed. Presently, (99m)Tc-mebrofenin hepatobiliary scintigraphy seems to be the most valuable quantitative liver function test, as it can measure multiple aspects of liver function in, specifically, the future remnant liver.
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Shigefuku R, Takahashi H, Kobayashi M, Ikeda H, Matsunaga K, Okuse C, Matsumoto N, Maeyama S, Sase S, Suzuki M, Itoh F. Pathophysiological analysis of nonalcoholic fatty liver disease by evaluation of fatty liver changes and blood flow using xenon computed tomography: can early-stage nonalcoholic steatohepatitis be distinguished from simple steatosis? J Gastroenterol 2012; 47:1238-47. [PMID: 22576023 DOI: 10.1007/s00535-012-0581-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2011] [Accepted: 03/05/2012] [Indexed: 02/04/2023]
Abstract
INTRODUCTION Effective noninvasive tests that can distinguish early-stage nonalcoholic steatohepatitis (NASH) from simple steatosis (SS) have long been sought. Our aim was to determine the possibility of noninvasively distinguishing early-stage NASH from SS. MATERIALS AND METHODS We used Fick's principle and the Kety-Schmidt equation to determine the hepatic tissue blood flow (TBF) in 65 NASH patients who underwent xenon computed tomography (Xe-CT). We calculated the lambda value (LV), i.e., Xe gas solubility coefficient, in liver and blood. We assessed the histological severity of fatty changes and fibrosis on the basis of Brunt's classification. Liver biopsy revealed SS in 9 patients and NASH in 56 patients. NASH stages 1 and 2 were classified as early-stage NASH (Ea-NASH; 38 patients) and stages 3 and 4 as advanced-stage NASH (Ad-NASH; 18 patients). We evaluated the differences in LV and TBF among the 3 groups. RESULTS LV was significantly lower in the Ad-NASH group than in the SS and Ea-NASH groups. Portal venous TBF (PVTBF) was significantly lower in the Ea-NASH group than in the SS group, and PVTBF was lower in the Ad-NASH group than in the Ea-NASH group. Total hepatic TBF (THTBF) was significantly different between the SS and Ea-NASH groups and between the SS and Ad-NASH groups. CONCLUSIONS In conclusion, measurements of TBF and LV are useful for evaluating the pathophysiological progression of NASH. In addition, these measurements can facilitate the differential diagnosis of SS and Ea-NASH, which may not be distinguishable by other means.
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Affiliation(s)
- Ryuta Shigefuku
- Division of Gastroenterology and Hepatology, St. Marianna University School of Medicine, Kawasaki, Kanagawa, Japan
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Abstract
Islet autoimmunity in type 1 diabetes results in the loss of the pancreatic β-cells. The consequences of insulin deficiency in the portal vein for liver fat are poorly understood. Under normal conditions, the portal vein provides 75% of the liver blood supply. Recent studies suggest that non-alcoholic fatty liver disease (NAFLD) may be more common in type 1 diabetes than previously thought, and may serve as an independent risk marker for some chronic diabetic complications. The pathogenesis of NAFLD remains obscure, but it has been hypothesized that hepatic fat accumulation in type 1 diabetes may be due to lipoprotein abnormalities, hyperglycemia-induced activation of the transcription factors carbohydrate response element-binding protein (ChREBP) and sterol regulatory element-binding protein 1c (SREBP-1c), upregulation of glucose transporter 2 (GLUT2) with subsequent intrahepatic fat synthesis, or a combination of these mechanisms. Novel approaches to non-invasive determinations of liver fat may clarify the consequences for liver metabolism when the pancreas has ceased producing insulin. This article aims to review the factors potentially contributing to hepatic steatosis in type 1 diabetes, and to assess the feasibility of using liver fat as a prognostic and/or diagnostic marker for the disease. It provides a background and a case for possible future studies in the field.
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Affiliation(s)
- Simon E Regnell
- Lund University, CRC, Department of Clinical Sciences, Diabetes and Celiac Disease Unit, Skåne University Hospital, Malmö, Sweden.
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Ono M, Ohtaki T, Tanemura K, Ishii M, Tsumagari S. Relationship between indocyanine green clearance test and feed intake and impaired hepatic function in dairy cows. J Vet Med Sci 2011; 73:1497-9. [PMID: 21712638 DOI: 10.1292/jvms.11-0161] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The purposes of this study were 1) to examine changes in the indocyanine green (ICG) clearance by feeding and 4-day fasting in dry cows, and (2) to investigate the relationship between ICG clearance and blood chemistry profile in postpartum cows. In 3 dry cows, post-feeding ICG half-life (T(1/2)) was shorter than the pre-feeding value, and post-fasting T(1/2) was longer than pre-feeding and post-feeding values. In 16 lactating cows, T(1/2) value at 2 weeks postpartum showed positive correlations with AST, T-Bil and γ-GTP. These results suggested that ICG clearance correlated with T-Bil and liver enzymes can be sensitive and accurate diagnostic marker for impaired liver function in dairy cows. In addition, ICG clearance is greatly affected by feeding and fasting.
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Affiliation(s)
- Mamiko Ono
- Laboratory of Theriogenology, Department of Veterinary Medicine, College of Bioresource Sciences, Nihon University, Fujisawa, Kanagawa 252–0880, Japan
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12
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Starke A, Schmidt S, Haudum A, Scholbach T, Wohlsein P, Beyerbach M, Rehage J. Evaluation of portal blood flow using transcutaneous and intraoperative Doppler ultrasonography in dairy cows with fatty liver. J Dairy Sci 2011; 94:2964-71. [DOI: 10.3168/jds.2011-4156] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2011] [Accepted: 02/18/2011] [Indexed: 11/19/2022]
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13
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Takahashi H, Suzuki M, Ikeda H, Kobayashi M, Sase S, Yotsuyanagi H, Maeyama S, Iino S, Itoh F. Evaluation of quantitative portal venous, hepatic arterial, and total hepatic tissue blood flow using xenon CT in alcoholic liver cirrhosis-comparison with liver cirrhosis related to hepatitis C virus and nonalcoholic steatohepatitis. Alcohol Clin Exp Res 2009; 34 Suppl 1:S7-S13. [PMID: 18986379 DOI: 10.1111/j.1530-0277.2008.00755.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
BACKGROUND/AIMS Xenon computed tomography (Xe-CT) is a noninvasive method of quantifying and visualizing tissue blood flow (TBF). For the liver, Xe-CT allows separate measurement of hepatic arterial and portal venous TBF. The present study evaluated the usefulness of Xe-CT as a noninvasive diagnostic procedure for measuring hepatic TBF in alcoholic liver cirrhosis (AL-LC), compared with liver cirrhosis related to nonalcoholic steatohepatitis (NASH), (NASH-LC), and hepatitis C virus (HCV), (C-LC). METHODS Xe-CT was performed on 22 patients with AL-LC, 7 patients with NASH-LC, and 24 patients with C-LC. Severity of LC was classified according to Child-Pugh classification. Correlations between hepatic TBF, Child-Pugh classification, and indocyanin green retention (ICG) rate after 15 minutes (ICG15R) were examined. Correlations of hepatic TBF in Child-Pugh class A to AL-LC, NASH-LC, and C-LC were also examined. RESULTS Portal venous TBF (PVTBF) displayed a significant negative correlation with Child-Pugh score and ICG15R (r = -0.432, p < 0.01, r = -0.442, p < 0.01, respectively). Moreover, ICG15R displayed a significant positive correlation with Child-Pugh score (r = 0.661, p < 0.001). Meanwhile, mean PVTBF and total hepatic TBF (THTBF) was significantly lower in AL-LC than in C-LC (p < 0.05). Mean PVTBF was significantly lower in Child-Pugh class A to AL-LC and NASH-LC than in that to C-LC (p < 0.05). Similarly, mean THTBF was significantly lower in Child-Pugh class A to NASH-LC than in that to C-LC (p < 0.05). CONCLUSIONS Measurement of hepatic TBF using Xe-CT is useful as a noninvasive, objective method of assessing the state of the liver in chronic liver disease.
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Affiliation(s)
- Hideaki Takahashi
- Division of Gastroenterology and Hepatology, Department of Internal Medicine, St. Marianna University, School of Medicine, 2-16-1 Sugao Miyamaeku, Kawasaki, 216-8511, Japan.
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14
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Gaiani S, Avogaro A, Bombonato G, Bolognesi M, Amor F, Vigili de Kreutzenberg S, Guarneri G, Sacerdoti D. Nonalcoholic fatty liver disease (NAFLD) in nonobese patients with diabetes: Prevalence and relationships with hemodynamic alterations detected with Doppler sonography(). J Ultrasound 2009; 12:1-5. [PMID: 23396636 PMCID: PMC3553245 DOI: 10.1016/j.jus.2008.12.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
AIM To evaluate the prevalence, severity, and hemodynamic features of nonalcoholic fatty liver disease (NAFLD) in nonobese diabetics. METHODS We studied 100 consecutive nonobese (body mass index [BMI] < 30) patients with type 1 (n = 17) or type 2 (n = 83) diabetes and no known causes of liver disease. Steatosis was diagnosed and graded with ultrasonography. Digital sonographic images of the liver and right kidney were analyzed with dedicated software (HDI-Lab), and the liver/kidney ratio of grey-scale intensity was calculated as an index of the severity of the steatosis. Severity scores ranging from 0 (none) to 5 (severe) were compared with sonographic and Doppler findings (right liver size, portal vein diameter and flow velocity, hepatic and splenic arterial pulsatility indices, hepatic-vein flow profile and A- and S-wave velocities). RESULTS The prevalence of steatosis was 24% in type I and 80% in type II diabetes (grade 1 in 17%, grade 2 in 34%, grade 3 in 33%, grade 4 in 9%, grade 5 in 7%). In patients with steatosis (especially those with grades 4-5 disease), hepatic volume was increased (p < 0.005). Portal vein diameter was increased in grade 5 steatosis. The hepatic artery pulsatility index was significantly increased, particularly in grades 4 and 5 (p < 0.0001); portal and A-wave velocities were significantly reduced in grades 3-5 (p < 0.001); and the hepatic vein flow profile was altered in 27% (biphasic: 20%, flat: 7%) patients with steatosis, although there was no correlation with severity. CONCLUSIONS NAFLD is very frequent in nonobese diabetics with type 2 but not type 1 disease, and it is associated with hepatomegaly and liver hemodynamic alterations only when it is severe.
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Affiliation(s)
- S. Gaiani
- Clinica Medica 5, Department of Clinical and Experimental Medicine, University of Padua, Italy
| | - A. Avogaro
- Diabetology and Metabolic Diseases, Department of Clinical and Experimental Medicine, University of Padua, Italy
| | - G.C. Bombonato
- Clinica Medica 5, Department of Clinical and Experimental Medicine, University of Padua, Italy
| | - M. Bolognesi
- Clinica Medica 5, Department of Clinical and Experimental Medicine, University of Padua, Italy
| | - F. Amor
- Clinica Medica 5, Department of Clinical and Experimental Medicine, University of Padua, Italy
| | - S. Vigili de Kreutzenberg
- Diabetology and Metabolic Diseases, Department of Clinical and Experimental Medicine, University of Padua, Italy
| | - G. Guarneri
- Diabetology and Metabolic Diseases, Department of Clinical and Experimental Medicine, University of Padua, Italy
| | - D. Sacerdoti
- Clinica Medica 5, Department of Clinical and Experimental Medicine, University of Padua, Italy
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15
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Slimani L, Kudomi N, Oikonen V, Jarvisalo M, Kiss J, Naum A, Borra R, Viljanen A, Sipila H, Ferrannini E, Savunen T, Nuutila P, Iozzo P. Quantification of liver perfusion with [(15)O]H(2)O-PET and its relationship with glucose metabolism and substrate levels. J Hepatol 2008; 48:974-82. [PMID: 18384905 DOI: 10.1016/j.jhep.2008.01.029] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2007] [Revised: 12/28/2007] [Accepted: 01/16/2008] [Indexed: 01/21/2023]
Abstract
BACKGROUND/AIMS Hepatic perfusion plays an important role in liver physiology and disease. This study was undertaken to (a) validate the use of Positron Emission Tomography (PET) and oxygen-15-labeled water ([(15)O]H(2)O) to quantify hepatic and portal perfusion, and (b) examine relationships between portal perfusion and liver glucose and lipid metabolism. METHODS Liver [(15)O]H(2)O-PET images were obtained in 14 pigs during fasting or hyperinsulinemia. Carotid arterial and portal venous blood were sampled for [(15)O]H(2)O activity; Doppler ultrasonography was used invasively as the reference method. A single arterial input compartment model was developed to estimate portal tracer kinetics and liver perfusion. Endogenous glucose production (EGP) and insulin-mediated whole body glucose uptake (wbGU) were determined by standard methods. RESULTS Hepatic arterial and portal venous perfusions were 0.15+/-0.07 and 1.11+/-0.34 ml/min/ml of tissue, respectively. The agreement between ultrasonography and [(15)O]H(2)O-PET was good for total and portal liver perfusion, and poor for arterial perfusion. Portal perfusion was correlated with EGP (r=or+0.62, p=0.03), triglyceride (r=or+0.66, p=0.01), free fatty acid levels (r=or+0.76, p=0.003), and plasma lactate levels (r=or-0.81, p=0.0009). CONCLUSIONS Estimates of liver perfusion by [(15)O]H(2)O-PET compared well with those by ultrasonography. The method allowed to predict portal tracer concentrations which is essential in human studies. Portal perfusion may affect liver nutrient handling.
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Affiliation(s)
- Lotfi Slimani
- Turku PET Centre, Turku University Hospital, University of Turku, P.O. Box 52, FIN-20521 Turku, Finland.
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Ramirez-Tortosa MC, Granados S, Ramirez-Tortosa CL, Ochoa JJ, Camacho P, García-Valdés L, Battino M, Quiles JL. Oxidative stress status in liver mitochondria and lymphocyte DNA damage of atherosclerotic rabbits supplemented with water soluble coenzyme Q10. Biofactors 2008; 32:263-73. [PMID: 19096124 DOI: 10.1002/biof.5520320131] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The effects of the administration of water soluble coenzyme Q10 (25 mg/kg per day) over 30 days, after 50 days feeding on a high-fat diet (3% lard + 1.3% cholesterol), were investigated in the plasma and liver mitochondria of rabbits. Results showed that this atherogenic diet enhanced lipid levels both in plasma and liver mitochondria, reduced plasma and mitochondrial concentrations of retinol and coenzyme Q10, led to higher DNA damage in peripheral blood lymphocytes and reactive oxygen species concentration in liver mitochondria. The treatment of animals with coenzyme Q10 reduced (to the healthy group levels) lipid concentration in liver mitochondria with no effect on plasma lipids, increased mitochondrial levels of alpha-tocopherol, restored mitochondrial coenzyme Q10 and improved alpha-tocopherol levels in plasma. Moreover, coenzyme Q10 supplementation reduced mitochondrial reactive oxygen species levels and decreased DNA damage in peripheral blood lymphocytes. The findings suggest that antioxidant therapy with coenzyme Q10 may be used in the treatment of liver pathologies associated to the intake of high-fat, atherogenic, diets.
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Affiliation(s)
- M Carmen Ramirez-Tortosa
- Department of Biochemistry and Molecular Biology II, Institute of Nutrition and Food Technology (INYTA), University of Granada, Granada, Spain.
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17
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Koti RS, Yang W, Glantzounis G, Quaglia A, Davidson BR, Seifalian AM. Effect of ischaemic preconditioning on hepatic oxygenation, microcirculation and function in a rat model of moderate hepatic steatosis. Clin Sci (Lond) 2005; 108:55-63. [PMID: 15341510 DOI: 10.1042/cs20040130] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
IPC (ischaemic preconditioning) may protect the steatotic liver, which is particularly susceptible to I/R (ischaemia/reperfusion) injury. Hepatic steatosis was induced in Sprague-Dawley rats with a high-cholesterol (2%) diet for 12 weeks after which rats were subjected to I/R (ischaemia/reperfusion; 45 min of lobar ischaemia followed by 2 h of reperfusion). Rats were divided into three study groups (n=6 each) receiving: (i) sham laparotomy alone, (ii) I/R, and (iii) IPC (5 min of ischaemia, followed by 10 min of reperfusion) before I/R. Hepatic extra- and intra-cellular oxygenation and HM (hepatic microcirculation) were measured with near-infrared spectroscopy and laser Doppler flowmetry respectively. Plasma liver enzymes and hepatic tissue ATP were measured as markers of liver injury. Histology showed moderate-grade steatosis in the livers. At the end of 2 h of reperfusion, I/R significantly decreased extra- and intra-cellular oxygenation concomitant with a failure of recovery of HM (21.1+/-14.4% of baseline; P<0.001 compared with sham animals). IPC increased intracellular oxygenation (redox state of the copper centre of cytochrome oxidase; P<0.05 compared with rats receiving I/R alone) and flow in HM (70.9+/-17.1% of baseline; P<0.001 compared with rats receiving I/R alone). Hepatocellular injury was significantly reduced with IPC compared with I/R injury alone (alanine aminotransferase, 474.8+/-122.3 compared with 5436.3+/-984.7 units/l respectively; P<0.01; aspartate aminotransferase, 630.8+/-76.9 compared with 3166.3+/-379.6 units/l respectively; P<0.01]. In conclusion, IPC has a hepatoprotective effect against I/R injury in livers with moderate steatosis. These data may have important clinical implications in liver surgery and transplantation.
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Affiliation(s)
- Rahul S Koti
- University Department of Surgery and Liver Transplantation Unit, Royal Free and University College Medical School, The Royal Free Hospital, London NW3 2QG, U.K
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Magalotti D, Marchesini G, Ramilli S, Berzigotti A, Bianchi G, Zoli M. Splanchnic haemodynamics in non-alcoholic fatty liver disease: effect of a dietary/pharmacological treatment. A pilot study. Dig Liver Dis 2004; 36:406-11. [PMID: 15248381 DOI: 10.1016/j.dld.2004.01.023] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND Previous studies demonstrated that in experimental animals fatty liver is associated with reduced hepatic blood flow and that metformin reverses steatosis, while no data were reported in humans. AIMS To evaluate the clinical relevance of echo-Doppler measurements and the effects of therapy in non-alcoholic fatty liver disease. PATIENTS Twenty patients with biopsy proven non-alcoholic fatty liver disease. METHODS Abdominal echo-Doppler examination was performed at enrolment and, in 11 patients, after 6 months of dietary/pharmacological therapy (metformin 500 mg three times a day). RESULTS Non-alcoholic fatty liver disease was characterised by hepatomegaly, bright echotexture and posterior attenuation. Mean portal blood velocity and flow were low-normal. Brightness and posterior attenuation significantly correlated with fat score in liver biopsies as well as with the hepatic veins spectrum. After therapy, echotexture improved and liver volume significantly decreased. Portal blood velocity and flow significantly increased, intrahepatic arterial indexes decreased and the spectrum of hepatic veins improved. CONCLUSIONS Fatty liver is associated with an impaired hepatic blood flow characterised by increased intrahepatic resistances. Vascular changes are reversed by treatment and can be measured by echo-Doppler which may be useful to evaluate the natural course of non-alcoholic fatty liver disease, and to monitor the putative beneficial effects of therapy.
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Affiliation(s)
- D Magalotti
- Department of Internal Medicine, Cardioangiology and Hepatology, Policlinico S. Orsola-Malpighi, Via Massarenti 9, 40138 Bologna, Italy
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Ijaz S, Yang W, Winslet MC, Seifalian AM. Impairment of Hepatic Microcirculation in Fatty Liver. Microcirculation 2003; 10:447-56. [PMID: 14745457 DOI: 10.1038/sj.mn.7800206] [Citation(s) in RCA: 142] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2002] [Accepted: 01/16/2003] [Indexed: 01/03/2023]
Abstract
Fatty liver or hepatic steatosis, which is the result of the abnormal accumulation of triacylglycerol within the cytoplasm of hepatocytes, is a common histological finding in human liver biopsy specimens that is attributed to the effects of alcohol excess, obesity, diabetes, or drugs. There is a general consensus that fatty liver compromises hepatic microcirculation, the common exchange network upon which hepatic arterial and portal inflows converge, regardless of underlying etiology. A significant reduction in hepatic microcirculation has been observed in human fatty donor livers and in experimental models of hepatic steatosis. There is an inverse correlation between the degree of fat infiltration and both total hepatic blood flow and flow in microcirculation. Fatty accumulation in the cytoplasm of the hepatocytes is associated with an increase in the cell volume that reduces the size of the hepatic sinusoid space by 50% compared with a normal liver and may result in partial or complete obstruction of the hepatic sinusoid space. As a result of impaired hepatic microcirculation, the hepatocytes of the fatty liver have reduced tolerance against ischemia-reperfusion injury, which affects about 25% of the donors for liver transplantation because severe steatosis is associated with a high risk of primary nonfunction after liver transplantation.
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Affiliation(s)
- Samia Ijaz
- University Department of Surgery, Royal Free and University College Medical School, University College London and the Royal Free Hospital, London NW3 2QG, UK
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