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Li Y, Yang P, Ye J, Xu Q, Wu J, Wang Y. Updated mechanisms of MASLD pathogenesis. Lipids Health Dis 2024; 23:117. [PMID: 38649999 PMCID: PMC11034170 DOI: 10.1186/s12944-024-02108-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Accepted: 04/11/2024] [Indexed: 04/25/2024] Open
Abstract
Metabolic dysfunction-associated steatotic liver disease (MASLD) has garnered considerable attention globally. Changing lifestyles, over-nutrition, and physical inactivity have promoted its development. MASLD is typically accompanied by obesity and is strongly linked to metabolic syndromes. Given that MASLD prevalence is on the rise, there is an urgent need to elucidate its pathogenesis. Hepatic lipid accumulation generally triggers lipotoxicity and induces MASLD or progress to metabolic dysfunction-associated steatohepatitis (MASH) by mediating endoplasmic reticulum stress, oxidative stress, organelle dysfunction, and ferroptosis. Recently, significant attention has been directed towards exploring the role of gut microbial dysbiosis in the development of MASLD, offering a novel therapeutic target for MASLD. Considering that there are no recognized pharmacological therapies due to the diversity of mechanisms involved in MASLD and the difficulty associated with undertaking clinical trials, potential targets in MASLD remain elusive. Thus, this article aimed to summarize and evaluate the prominent roles of lipotoxicity, ferroptosis, and gut microbes in the development of MASLD and the mechanisms underlying their effects. Furthermore, existing advances and challenges in the treatment of MASLD were outlined.
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Affiliation(s)
- Yuxuan Li
- Department of Cardiology, State Key Laboratory of Transvascular Implantation Devices, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
- Translational Medicine Center, The Affiliated Hospital of Hangzhou Normal University, Hangzhou, China
| | - Peipei Yang
- Translational Medicine Center, The Affiliated Hospital of Hangzhou Normal University, Hangzhou, China
| | - Jialu Ye
- Translational Medicine Center, The Affiliated Hospital of Hangzhou Normal University, Hangzhou, China
| | - Qiyuan Xu
- Wenzhou Medical University, Wenzhou, China
| | - Jiaqi Wu
- Translational Medicine Center, The Affiliated Hospital of Hangzhou Normal University, Hangzhou, China.
- Department of Gastroenterology, The Affiliated Hospital of Hangzhou Normal University, Hangzhou, China.
| | - Yidong Wang
- Department of Cardiology, State Key Laboratory of Transvascular Implantation Devices, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.
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Korbelius M, Kuentzel KB, Bradić I, Vujić N, Kratky D. Recent insights into lysosomal acid lipase deficiency. Trends Mol Med 2023; 29:425-438. [PMID: 37028992 DOI: 10.1016/j.molmed.2023.03.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 03/14/2023] [Accepted: 03/14/2023] [Indexed: 04/09/2023]
Abstract
Lysosomal acid lipase (LAL) is the sole enzyme known to degrade neutral lipids in the lysosome. Mutations in the LAL-encoding LIPA gene lead to rare lysosomal lipid storage disorders with complete or partial absence of LAL activity. This review discusses the consequences of defective LAL-mediated lipid hydrolysis on cellular lipid homeostasis, epidemiology, and clinical presentation. Early detection of LAL deficiency (LAL-D) is essential for disease management and survival. LAL-D must be considered in patients with dyslipidemia and elevated aminotransferase concentrations of unknown etiology. Enzyme replacement therapy, sometimes in combination with hematopoietic stem cell transplantation (HSCT), is currently the only therapy for LAL-D. New technologies based on mRNA and viral vector gene transfer are recent efforts to provide other effective therapeutic strategies.
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Affiliation(s)
- Melanie Korbelius
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, 8010 Graz, Austria
| | - Katharina B Kuentzel
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, 8010 Graz, Austria
| | - Ivan Bradić
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, 8010 Graz, Austria
| | - Nemanja Vujić
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, 8010 Graz, Austria
| | - Dagmar Kratky
- Gottfried Schatz Research Center, Molecular Biology and Biochemistry, Medical University of Graz, 8010 Graz, Austria.
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Lee KC, Wu PS, Lin HC. Pathogenesis and treatment of non-alcoholic steatohepatitis and its fibrosis. Clin Mol Hepatol 2023; 29:77-98. [PMID: 36226471 PMCID: PMC9845678 DOI: 10.3350/cmh.2022.0237] [Citation(s) in RCA: 31] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Accepted: 10/11/2022] [Indexed: 02/02/2023] Open
Abstract
The initial presentation of non-alcoholic steatohepatitis (NASH) is hepatic steatosis. The dysfunction of lipid metabolism within hepatocytes caused by genetic factors, diet, and insulin resistance causes lipid accumulation. Lipotoxicity, oxidative stress, mitochondrial dysfunction, and endoplasmic reticulum stress would further contribute to hepatocyte injury and death, leading to inflammation and immune dysfunction in the liver. During the healing process, the accumulation of an excessive amount of fibrosis might occur while healing. During the development of NASH and liver fibrosis, the gut-liver axis, adipose-liver axis, and renin-angiotensin system (RAS) may be dysregulated and impaired. Translocation of bacteria or its end-products entering the liver could activate hepatocytes, Kupffer cells, and hepatic stellate cells, exacerbating hepatic steatosis, inflammation, and fibrosis. Bile acids regulate glucose and lipid metabolism through Farnesoid X receptors in the liver and intestine. Increased adipose tissue-derived non-esterified fatty acids would aggravate hepatic steatosis. Increased leptin also plays a role in hepatic fibrogenesis, and decreased adiponectin may contribute to hepatic insulin resistance. Moreover, dysregulation of peroxisome proliferator-activated receptors in the liver, adipose, and muscle tissues may impair lipid metabolism. In addition, the RAS may contribute to hepatic fatty acid metabolism, inflammation, and fibrosis. The treatment includes lifestyle modification, pharmacological therapy, and non-pharmacological therapy. Currently, weight reduction by lifestyle modification or surgery is the most effective therapy. However, vitamin E, pioglitazone, and obeticholic acid have also been suggested. In this review, we will introduce some new clinical trials and experimental therapies for the treatment of NASH and related fibrosis.
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Affiliation(s)
- Kuei-Chuan Lee
- Division of Gastroenterology and Hepatology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan,Department of Medicine, National Yang Ming Chiao Tung University School of Medicine, Taipei, Taiwan,Corresponding author : Kuei-Chuan Lee Division of Gastroenterology and Hepatology, Department of Medicine, Taipei Veterans General Hospital, 201, Section 2, Shih-Pai Road, Taipei 11217, Taiwan Tel: +886 2 2871 2121, Fax: +886 2 2873 9318, E-mail:
| | - Pei-Shan Wu
- Division of Gastroenterology and Hepatology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan,Department of Medicine, National Yang Ming Chiao Tung University School of Medicine, Taipei, Taiwan,Endoscopy Center for Diagnosis and Treatment, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Han-Chieh Lin
- Division of Gastroenterology and Hepatology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan,Department of Medicine, National Yang Ming Chiao Tung University School of Medicine, Taipei, Taiwan,Corresponding author : Kuei-Chuan Lee Division of Gastroenterology and Hepatology, Department of Medicine, Taipei Veterans General Hospital, 201, Section 2, Shih-Pai Road, Taipei 11217, Taiwan Tel: +886 2 2871 2121, Fax: +886 2 2873 9318, E-mail:
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Lysosomal Acid Lipase Deficiency: Genetics, Screening, and Preclinical Study. Int J Mol Sci 2022; 23:ijms232415549. [PMID: 36555187 PMCID: PMC9779616 DOI: 10.3390/ijms232415549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 12/04/2022] [Accepted: 12/06/2022] [Indexed: 12/14/2022] Open
Abstract
Lysosomal acid lipase (LAL) is a lysosomal enzyme essential for the degradation of cholesteryl esters through the endocytic pathway. Deficiency of the LAL enzyme encoded by the LIPA gene leads to LAL deficiency (LAL-D) (OMIM 278000), one of the lysosomal storage disorders involving 50-60 genes. Among the two disease subtypes, the severe disease subtype of LAL-D is known as Wolman disease, with typical manifestations involving hepatomegaly, splenomegaly, vomiting, diarrhea, and hematopoietic abnormalities, such as anemia. In contrast, the mild disease subtype of this disorder is known as cholesteryl ester storage disease, with hypercholesterolemia, hypertriglyceridemia, and high-density lipoprotein disappearance. The prevalence of LAL-D is rare, but several treatment options, including enzyme replacement therapy, are available. Accordingly, a number of screening methodologies have been developed for this disorder. This review summarizes the current discussion on LAL-D, covering genetics, screening, and the tertiary structure of human LAL enzyme and preclinical study for the future development of a novel therapy.
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Yang Y, Li X, Liu Z, Ruan X, Wang H, Zhang Q, Cao L, Song L, Chen Y, Sun Y. Moderate Treadmill Exercise Alleviates NAFLD by Regulating the Biogenesis and Autophagy of Lipid Droplet. Nutrients 2022; 14:nu14224910. [PMID: 36432597 PMCID: PMC9697757 DOI: 10.3390/nu14224910] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2022] [Revised: 11/13/2022] [Accepted: 11/17/2022] [Indexed: 11/22/2022] Open
Abstract
Lipid droplet is a dynamic organelle that undergoes periods of biogenesis and degradation under environmental stimuli. The excessive accumulation of lipid droplets is the major characteristic of non-alcoholic fatty liver disease (NAFLD). Moderate aerobic exercise is a powerful intervention protecting against the progress of NAFLD. However, its impact on lipid droplet dynamics remains ambiguous. Mice were fed with 15 weeks of high-fat diet in order to induce NAFLD. Meanwhile, the mice performed 15 weeks of treadmill exercise. Our results showed that 15 weeks of regular moderate treadmill exercise alleviated obesity, insulin intolerance, hyperlipidemia, and hyperglycemia induced by HFD. Importantly, exercise improved histological phenotypes of NAFLD, including hepatic steatosis, inflammation, and locular ballooning, as well as prevented liver fat deposition and liver injury induced by HFD. Exercise reduced hepatic lipid droplet size, and moreover, it reduced PLIN2 protein level and increased PLIN3 protein level in the liver of HFD mice. Interestingly, our results showed that exercise did not significantly affect the gene expressions of DGAT1, DGAT2, or SEIPIN, which were involved in TG synthesis. However, it did reduce the expressions of FITM2, CIDEA, and FSP27, which were major involved in lipid droplet growth and budding, and lipid droplet expansion. In addition, exercise reduced ATGL protein level in HFD mice, and regulated lipophagy-related markers, including increasing ATG5, LAMP1, LAMP2, LAL, and CTSD, decreasing LC3II/I and p62, and promoting colocalization of LAMP1 with LDs. In summary, our data suggested that 15 weeks of moderate treadmill exercise was beneficial for regulating liver lipid droplet dynamics in HFD mice by inhibiting abnormal lipid droplets expansion and enhancing clearance of lipid droplets by lysosomes during the lipophagic process, which might provide highly flexible turnover for lipid mobilization and metabolism. Abbreviations: β-actin: actin beta; ATG5: autophagy related 5; LAMP2: lysosomal-associated membrane protein 2; LAMP1: lysosomal-associated membrane protein 1; SQSTM1/p62: sequestosome 1; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; ATGL: adipose triglyceride lipase; CSTD: cathepsin D; LAL: lysosomal acid lipase; DGAT1: diacylglycerol-o-acyltransferase 1; DGAT2: diacylglycerol-o-acyltransferase 2; CIDEA: cell death inducing dffa-like effector a; CIDEC/FSP27: cell death inducing dffa-like effector c; FITM2: fat storage-inducing transmembrane protein 2; PLIN2: adipose differentiation related protein; PLN3: tail-interacting protein 47; HSP90: heat shock protein 90; SREBP1c: sterol regulatory element binding protein-1c; chREBP: carbohydrate response element binding protein.
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Affiliation(s)
- Yangjun Yang
- Key Laboratory of Adolescent Health Assessment and Exercise Intervention of Ministry of Education, East China Normal University, Shanghai 200241, China
- College of Physical Education and Health, East China Normal University, Shanghai 200241, China
| | - Xi Li
- Key Laboratory of Adolescent Health Assessment and Exercise Intervention of Ministry of Education, East China Normal University, Shanghai 200241, China
- College of Physical Education and Health, East China Normal University, Shanghai 200241, China
| | - Zonghan Liu
- Key Laboratory of Adolescent Health Assessment and Exercise Intervention of Ministry of Education, East China Normal University, Shanghai 200241, China
- College of Physical Education and Health, East China Normal University, Shanghai 200241, China
| | - Xinyu Ruan
- Key Laboratory of Adolescent Health Assessment and Exercise Intervention of Ministry of Education, East China Normal University, Shanghai 200241, China
- College of Physical Education and Health, East China Normal University, Shanghai 200241, China
| | - Huihui Wang
- Key Laboratory of Adolescent Health Assessment and Exercise Intervention of Ministry of Education, East China Normal University, Shanghai 200241, China
- College of Physical Education and Health, East China Normal University, Shanghai 200241, China
| | - Qiang Zhang
- Key Laboratory of Adolescent Health Assessment and Exercise Intervention of Ministry of Education, East China Normal University, Shanghai 200241, China
- College of Physical Education and Health, East China Normal University, Shanghai 200241, China
| | - Lu Cao
- Key Laboratory of Adolescent Health Assessment and Exercise Intervention of Ministry of Education, East China Normal University, Shanghai 200241, China
- College of Physical Education and Health, East China Normal University, Shanghai 200241, China
| | - Luchen Song
- Key Laboratory of Adolescent Health Assessment and Exercise Intervention of Ministry of Education, East China Normal University, Shanghai 200241, China
- College of Physical Education and Health, East China Normal University, Shanghai 200241, China
| | - Yinghong Chen
- Key Laboratory of Adolescent Health Assessment and Exercise Intervention of Ministry of Education, East China Normal University, Shanghai 200241, China
- College of Physical Education and Health, East China Normal University, Shanghai 200241, China
| | - Yi Sun
- Key Laboratory of Adolescent Health Assessment and Exercise Intervention of Ministry of Education, East China Normal University, Shanghai 200241, China
- College of Physical Education and Health, East China Normal University, Shanghai 200241, China
- Correspondence: ; Tel.: +86-021-54341197
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Bashir A, Duseja A, Verma A, De A, Tiwari P. Lysosomal Acid Lipase Activity in Non-alcoholic Fatty Liver Disease as a Novel Diagnostic and Therapeutic Target: A Systematic Literature Review of Current Evidence and Future Directions. J Clin Exp Hepatol 2022; 12:1535-1546. [PMID: 36340307 PMCID: PMC9630019 DOI: 10.1016/j.jceh.2022.04.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Accepted: 04/10/2022] [Indexed: 12/12/2022] Open
Abstract
Background and aim Non-alcoholic fatty liver disease (NAFLD) presents with the accumulation of excessive intra-hepatic fat without significant alcohol intake. Multifactorial pathogenesis is reported to be involved. Reduced lysosomal acid lipase (LAL) activity is suggested as one of the novel-involved pathogenic mechanisms. This review summarizes the available evidence on the role of LAL activity in NAFLD pathogenesis. Methods Four databases namely, PubMed/Medline, Science direct, Cochrane Library, and Google scholar were searched to identify relevant observational records evaluating the role of LAL activity in the pathogenesis of NAFLD. All studies were assessed for their quality by using Newcastle-Ottawa Scale or The Joanna Briggs Institute Critical Appraisal tools for cohort and cross-sectional studies, respectively. The estimates of LAL activity and other clinical outcomes were expressed as mean (SD) and number (%) as presented in the primary studies. Results A total of nine good quality studies with 1711 patients with NAFLD and 877 controls from different groups (healthy volunteers, alcoholics, cryptogenic cirrhosis, and HCV-positive) were included. From the NAFLD group, 59.55% were males and the overall mean age ranged between the studies from 12.6 ± 8.5 months in pediatrics to 58.90 ± 13.82 years in adults. In the NAFLD group, the LAL activity varied from 0.53 ± 0.08 to 1.3 ± 0.70 (nmol/spot/hr) between the studies which was less than all control groups except cryptogenic cirrhosis patients (0.5 ± 0.15 nmol/spot/hr). Of the other outcomes of interest, ALT, AST, total cholesterol, triglyceride, and LDL cholesterol were found elevated in NAFLD patients than in controls. Conclusion The current evidence suggests a potential correlation of reduced LAL activity with NAFLD pathogenesis according to its severity. Large-scale studies are recommended, more importantly in patients with NAFLD having no metabolic or genetic involvement. Further LAL can act as a new non-invasive diagnostic biomarker to identify that specific NAFLD subgroup.
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Key Words
- ALT, Alanine aminotransferase
- AST, Aspartate aminotransferase
- CESD, Cholesterol ester storage disease
- HCC, Hepatocellular carcinoma
- JBI, Joanna Briggs Institute
- LAL
- LAL, Lysosomal acid lipase
- MAFLD, Metabolic (dysfunction)-associated fatty liver disease
- NAFLD
- NAFLD, Non-alcoholic fatty liver disease
- NASH
- NASH, Non-alcoholic steatohepatitis
- NOS, Newcastle–Ottawa Scale
- PNPLA3, Patatin-like phospholipase domain containing 3 protein
- WD, Wolman disease
- pathogenesis
- systematic review
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Affiliation(s)
- Aamir Bashir
- Department of Pharmacy Practice, National Institute of Pharmaceutical Education and Research, S.A.S. Nagar Mohali, Punjab, 160062, India
| | - Ajay Duseja
- Department of Hepatology, Post Graduate Institute of Medical Education and Research, Chandigarh, 160012, India
| | - Ashish Verma
- Department of Pharmacy Practice, National Institute of Pharmaceutical Education and Research, S.A.S. Nagar Mohali, Punjab, 160062, India
| | - Arka De
- Department of Hepatology, Post Graduate Institute of Medical Education and Research, Chandigarh, 160012, India
| | - Pramil Tiwari
- Department of Pharmacy Practice, National Institute of Pharmaceutical Education and Research, S.A.S. Nagar Mohali, Punjab, 160062, India
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Besler KJ, Blanchard V, Francis GA. Lysosomal acid lipase deficiency: A rare inherited dyslipidemia but potential ubiquitous factor in the development of atherosclerosis and fatty liver disease. Front Genet 2022; 13:1013266. [PMID: 36204319 PMCID: PMC9530988 DOI: 10.3389/fgene.2022.1013266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2022] [Accepted: 09/06/2022] [Indexed: 11/13/2022] Open
Abstract
Lysosomal acid lipase (LAL), encoded by the gene LIPA, is the sole neutral lipid hydrolase in lysosomes, responsible for cleavage of cholesteryl esters and triglycerides into their component parts. Inherited forms of complete (Wolman Disease, WD) or partial LAL deficiency (cholesteryl ester storage disease, CESD) are fortunately rare. Recently, LAL has been identified as a cardiovascular risk gene in genome-wide association studies, though the directionality of risk conferred remains controversial. It has also been proposed that the low expression and activity of LAL in arterial smooth muscle cells (SMCs) that occurs inherently in nature is a likely determinant of the propensity of SMCs to form the majority of foam cells in atherosclerotic plaque. LAL also likely plays a potential role in fatty liver disease. This review highlights the nature of LAL gene mutations in WD and CESD, the association of LAL with prediction of cardiovascular risk from genome-wide association studies, the importance of relative LAL deficiency in SMC foam cells, and the need to further interrogate the pathophysiological impact and cell type-specific role of enhancing LAL activity as a novel treatment strategy to reduce the development and induce the regression of ischemic cardiovascular disease and fatty liver.
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Wit M, Trujillo-Viera J, Strohmeyer A, Klingenspor M, Hankir M, Sumara G. When fat meets the gut-focus on intestinal lipid handling in metabolic health and disease. EMBO Mol Med 2022; 14:e14742. [PMID: 35437952 PMCID: PMC9081902 DOI: 10.15252/emmm.202114742] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 02/10/2022] [Accepted: 02/11/2022] [Indexed: 12/12/2022] Open
Abstract
The regular overconsumption of energy‐dense foods (rich in lipids and sugars) results in elevated intestinal nutrient absorption and consequently excessive accumulation of lipids in the liver, adipose tissue, skeletal muscles, and other organs. This can eventually lead to obesity and obesity‐associated diseases such as type 2 diabetes (T2D), non‐alcoholic fatty liver disease (NAFLD), cardiovascular disease, and certain types of cancer, as well as aggravate inflammatory bowel disease (IBD). Therefore, targeting the pathways that regulate intestinal nutrient absorption holds significant therapeutic potential. In this review, we discuss the molecular and cellular mechanisms controlling intestinal lipid handling, their relevance to the development of metabolic diseases, and emerging therapeutic strategies.
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Affiliation(s)
- Magdalena Wit
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warszawa, Poland
| | - Jonathan Trujillo-Viera
- Rudolf-Virchow-Zentrum, Center for Integrative and Translational Bioimaging, University of Würzburg, Würzburg, Germany
| | - Akim Strohmeyer
- Chair for Molecular Nutritional Medicine, Technical University of Munich, TUM School of Life Sciences Weihenstephan, Freising, Germany.,EKFZ - Else Kröner-Fresenius-Center for Nutritional Medicine, Technical University of Munich, Munich, Germany.,ZIEL - Institute for Food & Health, Technical University of Munich, Freising, Germany
| | - Martin Klingenspor
- Chair for Molecular Nutritional Medicine, Technical University of Munich, TUM School of Life Sciences Weihenstephan, Freising, Germany.,EKFZ - Else Kröner-Fresenius-Center for Nutritional Medicine, Technical University of Munich, Munich, Germany.,ZIEL - Institute for Food & Health, Technical University of Munich, Freising, Germany
| | - Mohammed Hankir
- Department of General, Visceral, Transplant, Vascular and Pediatric Surgery, University Hospital Wuerzburg, Wuerzburg, Germany
| | - Grzegorz Sumara
- Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warszawa, Poland
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Molecular and histological traits of reduced lysosomal acid lipase activity in the fatty liver. Cell Death Dis 2021; 12:1092. [PMID: 34795230 PMCID: PMC8602623 DOI: 10.1038/s41419-021-04382-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 10/26/2021] [Accepted: 11/03/2021] [Indexed: 01/05/2023]
Abstract
Recent studies demonstrated reduced blood lysosomal acid lipase (LAL) activity in patients with nonalcoholic fatty liver disease (NAFLD). We aimed to verify hepatic LAL protein content and activity in in vitro and in vivo models of fat overload and in NAFLD patients. LAL protein content and activity were firstly evaluated in Huh7 cells exposed to high-glucose/high-lipid (HGHL) medium and in the liver of C57BL/6 mice fed with high-fat diet (HFD) for 4 and 8 months. LAL protein was also evaluated by immunohistochemistry in liver biopsies from 87 NAFLD patients and 10 controls, and correlated with hepatic histology. Huh7 cells treated with HGHL medium showed a significant reduction of LAL activity, which was consistent with reduced LAL protein levels by western blotting using an antibody towards the N-term of the enzyme. Conversely, antibodies towards the C-term of the enzyme evidenced LAL accumulation, suggesting a post-translational modification that masks the LAL N-term epitope and affects enzymatic activity. Indeed, we found a high rate of ubiquitination and extra-lysosomal localization of LAL protein in cells treated with HGHL medium. Consistent with these findings, inhibition of proteasome triggered dysfunctional LAL accumulation and affected LAL activity. Accumulation of ubiquitinated/dysfunctional LAL was also found in the liver of HFD fed mice. In NAFLD patients, hepatic levels of non-ubiquitinated/functional LAL were lower than in controls and inversely correlated with disease activity and some of the hallmarks of reduced LAL. Fat overload leads to LAL ubiquitination and impairs its function, possibly reducing hepatic fat disposal and promoting NAFLD activity.
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Thoen RU, Longo L, Neto SC, Álvares-da-Silva MR. Low levels of Lysosomal Acid Lipase (LAL) activity increases necroinflammation in adult patients with biopsy-proven metabolic associated fatty liver disease. Clin Res Hepatol Gastroenterol 2021; 45:101638. [PMID: 33662773 DOI: 10.1016/j.clinre.2021.101638] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 12/29/2020] [Accepted: 01/16/2021] [Indexed: 02/07/2023]
Abstract
INTRODUCTION AND OBJECTIVE Metabolic associated fatty liver disease (MAFLD), characterized by intra-hepatic fat accumulation, will soon be the leading cause of end-stage liver disease. Lysosomal Acid Lipase (LAL) is a key enzyme in lipid metabolism. We investigated its activity in patients with biopsy-proven MAFLD. METHODS Prospective cross-sectional study in patients with biopsy-proven MAFLD. Blood LAL-activity (pmol/punch/h) was measured with dried blood spot extracts using Lalistat 2. Demographic, clinical, and laboratory data were collected. RESULTS 101 adult patients were recruited. Among them, 11.9% had a diagnosis of MAFLD without steatohepatitis and 88.1% had MAFLD with steatohepatitis. The median of LAL-activity in patients with MAFLD was 76.8 pmol/punch/h. MAFLD patients with steatohepatitis showed an increase in gamma-glutamyl transferase (p = 0.042), insulin (p = 0.001), homeostatic model assessment for insulin resistance (HOMA-IR, p = 0.001) and advanced liver fibrosis (p < 0.001), compared to cases of MAFLD without steatohepatitis. There was no statistical difference in LAL-activity between the cases (p = 0.296). When considering LAL-activity above and below 77 pmol/punch/h as a cut-off value, patients with reduced LAL-activity had a significant increase in necroinflammatory activity according to the METAVIR score (p = 0.040), and NAFLD activity score (NAS, p = 0.031) compared to cases with higher LAL-activity. CONCLUSION Our findings suggest that reduced LAL-activity is associated with increased necroinflammatory activity and severity of the NAS. A better knowledge of the role of LAL may provide new insights into the pathogenesis and progression of MAFLD.
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Affiliation(s)
- Rutiane Ullmann Thoen
- Graduate Program in Gastroenterology and Hepatology, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil; Experimental Laboratory of Hepatology and Gastroenterology, Experimental Research Center, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil
| | - Larisse Longo
- Graduate Program in Gastroenterology and Hepatology, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil; Experimental Laboratory of Hepatology and Gastroenterology, Experimental Research Center, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil.
| | - Santiago Cassales Neto
- Graduate Program in Gastroenterology and Hepatology, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | - Mário Reis Álvares-da-Silva
- Graduate Program in Gastroenterology and Hepatology, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil; Experimental Laboratory of Hepatology and Gastroenterology, Experimental Research Center, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil; Division of Gastroenterology, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil
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Li F, Zhao X, Li H, Liu Y, Zhang Y, Huang X, Cao J, Du F, Wu D, Yu H. Hepatic lysosomal acid lipase drives the autophagy-lysosomal response and alleviates cholesterol metabolic disorder in ApoE deficient mice. Biochim Biophys Acta Mol Cell Biol Lipids 2021; 1866:159027. [PMID: 34416392 DOI: 10.1016/j.bbalip.2021.159027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 07/22/2021] [Accepted: 08/13/2021] [Indexed: 02/07/2023]
Abstract
Lysosomal acid lipase (LAL)-dependent lipolysis degrades cholesteryl ester (CE) and triglyceride in the lysosome. LAL deficiency in human and mice leads to hypercholesterolemia, hepatic CE deposition, and atherosclerosis. Despite its hepatocyte-specific deficiency leads to CE accumulation, the regulation of LAL in cholesterol metabolic disease remains elusive. For the in vitro study, the target gene Lipa was transfected with recombinant shRNA or lentiviral vector in Hepa1-6 cells. It was found that LAL silencing in cells affected lysosomal function by reducing LAL activity and proteolytic activity, and altered the expression of genes related to cholesterol metabolism and autophagy, leading to cholesterol accumulation; whereas LAL overexpression improved the above effects. To explore the impacts of hepatic LAL on cholesterol metabolic disease in vivo, apolipoprotein E deficient (ApoE-/-) mice were intravenously injected with lentivirus to achieve hepatic LAL overexpression and fed a Western diet for 16 weeks. The results showed that hepatic LAL overexpression significantly reduced plasma lipid levels, alleviated inflammation and oxidative status in plasma and liver, and attenuated hepatic steatosis and fibrosis in ApoE-/- mice. Mechanically, hepatic LAL promoted cholesterol transport and biliary excretion by increasing liver X receptor alpha (LXRα) and its downstream genes, and modulated the compliance of the autophagy-lysosomal pathway. Our data provide the original evidence of the validity of hepatic LAL in controlling cholesterol metabolism and liver homeostasis, suggesting that targeting hepatic LAL may provide a promising approach to rescue cholesterol metabolic disorders, such as hypercholesterolemia and liver disease.
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Affiliation(s)
- Feifei Li
- Department of Biochemistry and Molecular Biology, Hubei Provincial Key Laboratory of Developmentally Originated Disease, Wuhan University School of Basic Medical Sciences, Wuhan, Hubei 430071, China
| | - Xiaojie Zhao
- Department of Biochemistry and Molecular Biology, Hubei Provincial Key Laboratory of Developmentally Originated Disease, Wuhan University School of Basic Medical Sciences, Wuhan, Hubei 430071, China
| | - Hao Li
- Department of Pharmacy, Zhongnan Hospital of Wuhan University, Wuhan, Hubei 430071, China
| | - Yu Liu
- Department of Biochemistry and Molecular Biology, Hubei Provincial Key Laboratory of Developmentally Originated Disease, Wuhan University School of Basic Medical Sciences, Wuhan, Hubei 430071, China
| | - Yu Zhang
- Department of Biochemistry and Molecular Biology, Hubei Provincial Key Laboratory of Developmentally Originated Disease, Wuhan University School of Basic Medical Sciences, Wuhan, Hubei 430071, China
| | - Xiaopeng Huang
- Department of Biochemistry and Molecular Biology, Hubei Provincial Key Laboratory of Developmentally Originated Disease, Wuhan University School of Basic Medical Sciences, Wuhan, Hubei 430071, China
| | - Jia Cao
- Department of Biochemistry and Molecular Biology, Hubei Provincial Key Laboratory of Developmentally Originated Disease, Wuhan University School of Basic Medical Sciences, Wuhan, Hubei 430071, China
| | - Fen Du
- Department of Biochemistry and Molecular Biology, Hubei Provincial Key Laboratory of Developmentally Originated Disease, Wuhan University School of Basic Medical Sciences, Wuhan, Hubei 430071, China
| | - Dongfang Wu
- Department of Pharmacy, Zhongnan Hospital of Wuhan University, Wuhan, Hubei 430071, China.
| | - Hong Yu
- Department of Biochemistry and Molecular Biology, Hubei Provincial Key Laboratory of Developmentally Originated Disease, Wuhan University School of Basic Medical Sciences, Wuhan, Hubei 430071, China.
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12
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Nonalcoholic Fatty Liver Disease: Focus on New Biomarkers and Lifestyle Interventions. Int J Mol Sci 2021; 22:ijms22083899. [PMID: 33918878 PMCID: PMC8069944 DOI: 10.3390/ijms22083899] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 04/07/2021] [Accepted: 04/08/2021] [Indexed: 02/07/2023] Open
Abstract
Nonalcoholic fatty liver disease (NAFLD) is considered a hepatic manifestation of metabolic syndrome, characterized from pathological changes in lipid and carbohydrate metabolism. Its main characteristics are excessive lipid accumulation and oxidative stress, which create a lipotoxic environment in hepatocytes leading to liver injury. Recently, many studies have focused on the identification of the genetic and epigenetic modifications that also contribute to NAFLD pathogenesis and their prognostic implications. The present review is aimed to discuss on cellular and metabolic alterations associated with NAFLD, which can be helpful to identify new noninvasive biomarkers. The identification of accumulated lipids in the cell membranes, as well as circulating cytokeratins and exosomes, provides new insights in understanding of NAFLD. This review also suggests that lifestyle modifications remain the main prevention and/or treatment for NAFLD.
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13
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How does hepatic lipid accumulation lead to lipotoxicity in non-alcoholic fatty liver disease? Hepatol Int 2021; 15:21-35. [PMID: 33548031 PMCID: PMC7886759 DOI: 10.1007/s12072-020-10121-2] [Citation(s) in RCA: 148] [Impact Index Per Article: 49.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 12/10/2020] [Indexed: 02/06/2023]
Abstract
BACKGROUND Non-alcoholic fatty liver disease (NAFLD), characterized as excess lipid accumulation in the liver which is not due to alcohol use, has emerged as one of the major health problems around the world. The dysregulated lipid metabolism creates a lipotoxic environment which promotes the development of NAFLD, especially the progression from simple steatosis (NAFL) to non-alcoholic steatohepatitis (NASH). PURPOSEAND AIM This review focuses on the mechanisms of lipid accumulation in the liver, with an emphasis on the metabolic fate of free fatty acids (FFAs) in NAFLD and presents an update on the relevant cellular processes/mechanisms that are involved in lipotoxicity. The changes in the levels of various lipid species that result from the imbalance between lipolysis/lipid uptake/lipogenesis and lipid oxidation/secretion can cause organellar dysfunction, e.g. ER stress, mitochondrial dysfunction, lysosomal dysfunction, JNK activation, secretion of extracellular vesicles (EVs) and aggravate (or be exacerbated by) hypoxia which ultimately lead to cell death. The aim of this review is to provide an overview of how abnormal lipid metabolism leads to lipotoxicity and the cellular mechanisms of lipotoxicity in the context of NAFLD.
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14
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Vos DY, van de Sluis B. Function of the endolysosomal network in cholesterol homeostasis and metabolic-associated fatty liver disease (MAFLD). Mol Metab 2021; 50:101146. [PMID: 33348067 PMCID: PMC8324686 DOI: 10.1016/j.molmet.2020.101146] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Revised: 11/26/2020] [Accepted: 12/14/2020] [Indexed: 02/08/2023] Open
Abstract
Background Metabolic-associated fatty liver disease (MAFLD), also known as non-alcoholic fatty liver disease, has become the leading cause of chronic liver disease worldwide. In addition to hepatic accumulation of triglycerides, dysregulated cholesterol metabolism is an important contributor to the pathogenesis of MAFLD. Maintenance of cholesterol homeostasis is highly dependent on cellular cholesterol uptake and, subsequently, cholesterol transport to other membrane compartments, such as the endoplasmic reticulum (ER). Scope of review The endolysosomal network is key for regulating cellular homeostasis and adaptation, and emerging evidence has shown that the endolysosomal network is crucial to maintain metabolic homeostasis. In this review, we will summarize our current understanding of the role of the endolysosomal network in cholesterol homeostasis and its implications in MAFLD pathogenesis. Major conclusions Although multiple endolysosomal proteins have been identified in the regulation of cholesterol uptake, intracellular transport, and degradation, their physiological role is incompletely understood. Further research should elucidate their role in controlling metabolic homeostasis and development of fatty liver disease. The intracellular cholesterol transport is tightly regulated by the endocytic and lysosomal network. Dysfunction of the endolysosomal network affects hepatic lipid homeostasis. The endosomal sorting of lipoprotein receptors is precisely regulated and is not a bulk process.
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Affiliation(s)
- Dyonne Y Vos
- Department of Pediatrics, section Molecular Genetics, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - Bart van de Sluis
- Department of Pediatrics, section Molecular Genetics, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.
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15
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Lee NY, Shin MJ, Youn GS, Yoon SJ, Choi YR, Kim HS, Gupta H, Han SH, Kim BK, Lee DY, Park TS, Sung H, Kim BY, Suk KT. Lactobacillus attenuates progression of nonalcoholic fatty liver disease by lowering cholesterol and steatosis. Clin Mol Hepatol 2020; 27:110-124. [PMID: 33317254 PMCID: PMC7820205 DOI: 10.3350/cmh.2020.0125] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Accepted: 09/13/2020] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND/AIMS Nonalcoholic fatty liver disease (NAFLD) is closely related to gut-microbiome. There is a paucity of research on which strains of gut microbiota affect the progression of NAFLD. This study explored the NAFLD-associated microbiome in humans and the role of Lactobacillus in the progression of NAFLD in mice. METHODS The gut microbiome was analyzed via next-generation sequencing in healthy people (n=37) and NAFLD patients with elevated liver enzymes (n=57). Six-week-old male C57BL/6J mice were separated into six groups (n=10 per group; normal, Western, and four Western diet + strains [109 colony-forming units/g for 8 weeks; L. acidophilus, L. fermentum, L. paracasei, and L. plantarum]). Liver/body weight ratio, liver pathology, serum analysis, and metagenomics in the mice were examined. RESULTS Compared to healthy subjects (1.6±4.3), NAFLD patients showed an elevated Firmicutes/Bacteroidetes ratio (25.0±29.0) and a reduced composition of Akkermansia and L. murinus (P<0.05). In the animal experiment, L. acidophilus group was associated with a significant reduction in liver/body weight ratio (5.5±0.4) compared to the Western group (6.2±0.6) (P<0.05). L. acidophilus (41.0±8.6), L. fermentum (44.3±12.6), and L. plantarum (39.0±7.6) groups showed decreased cholesterol levels compared to the Western group (85.7±8.6) (P<0.05). In comparison of steatosis, L. acidophilus (1.9±0.6), L. plantarum (2.4±0.7), and L. paracasei (2.0±0.9) groups showed significant improvement of steatosis compared to the Western group (2.6±0.5) (P<0.05). CONCLUSION Ingestion of Lactobacillus, such as L. acidophilus, L. fermentum, and L. plantarum, ameliorates the progression of nonalcoholic steatosis by lowering cholesterol. The use of Lactobacillus can be considered as a useful strategy for the treatment of NAFLD.
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Affiliation(s)
- Na Young Lee
- Institue for Liver and Digestive Diseases, Hallym University College of Medicine, Chuncheon, Korea
| | - Min Jea Shin
- Institue for Liver and Digestive Diseases, Hallym University College of Medicine, Chuncheon, Korea
| | - Gi Soo Youn
- Institue for Liver and Digestive Diseases, Hallym University College of Medicine, Chuncheon, Korea
| | - Sang Jun Yoon
- Institue for Liver and Digestive Diseases, Hallym University College of Medicine, Chuncheon, Korea
| | - Ye Rin Choi
- Institue for Liver and Digestive Diseases, Hallym University College of Medicine, Chuncheon, Korea
| | - Hyeong Seop Kim
- Institue for Liver and Digestive Diseases, Hallym University College of Medicine, Chuncheon, Korea
| | - Haripriya Gupta
- Institue for Liver and Digestive Diseases, Hallym University College of Medicine, Chuncheon, Korea
| | - Sang Hak Han
- Department of Pathology, Hallym University College of Medicine, Chuncheon, Korea
| | | | - Do Yup Lee
- Department of Agricultural Biotechnology, Seoul National University, Seoul, Korea
| | - Tae Sik Park
- Department of Life Science, Gachon University, Sungnam, Korea
| | - Hotaik Sung
- Department of Medicine, College of Medicine, Kyungpook National University, Daegu, Korea
| | | | - Ki Tae Suk
- Institue for Liver and Digestive Diseases, Hallym University College of Medicine, Chuncheon, Korea
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16
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Carotti S, Aquilano K, Valentini F, Ruggiero S, Alletto F, Morini S, Picardi A, Antonelli-Incalzi R, Lettieri-Barbato D, Vespasiani-Gentilucci U. An overview of deregulated lipid metabolism in nonalcoholic fatty liver disease with special focus on lysosomal acid lipase. Am J Physiol Gastrointest Liver Physiol 2020; 319:G469-G480. [PMID: 32812776 DOI: 10.1152/ajpgi.00049.2020] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Obesity and type 2 diabetes are frequently complicated by excess fat accumulation in the liver, which is known as nonalcoholic fatty liver disease (NAFLD). In this context, liver steatosis develops as a result of the deregulation of pathways controlling de novo lipogenesis and fat catabolism. Recent evidences suggest the clinical relevance of a reduction in the activity of lysosomal acid lipase (LAL), which is a key enzyme for intracellular fat disposal, in patients with NAFLD. In this review, we provided a comprehensive overview of the critical steps in hepatic fat metabolism and alterations in these pathways in NAFLD, with a special focus on lipophagy and LAL activity. During NAFLD, hepatic fat metabolism is impaired at several levels, which is significantly contributed to by impaired lipophagy, in which reduced LAL activity may play an important role. For further research and intervention in NAFLD, targeting LAL activity may provide interesting perspectives.
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Affiliation(s)
- Simone Carotti
- Unit of Microscopic and Ultrastructural Anatomy, University Campus Bio-Medico, Rome, Italy
| | - Katia Aquilano
- Department of Biology, University of Rome, Tor Vergata, Rome, Italy
| | - Francesco Valentini
- Unit of Microscopic and Ultrastructural Anatomy, University Campus Bio-Medico, Rome, Italy
| | - Sergio Ruggiero
- Unit of Microscopic and Ultrastructural Anatomy, University Campus Bio-Medico, Rome, Italy
| | - Francesca Alletto
- Unit of Internal Medicine and Hepatology, University Campus Bio-Medico, Rome, Italy
| | - Sergio Morini
- Unit of Microscopic and Ultrastructural Anatomy, University Campus Bio-Medico, Rome, Italy
| | - Antonio Picardi
- Unit of Internal Medicine and Hepatology, University Campus Bio-Medico, Rome, Italy
| | | | - Daniele Lettieri-Barbato
- Department of Biology, University of Rome, Tor Vergata, Rome, Italy.,IRCCS Fondazione Santa Lucia, Rome, Italy
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17
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Park SL, Li Y, Sheng X, Hom V, Xia L, Zhao K, Pooler L, Setiawan VW, Lim U, Monroe KR, Wilkens LR, Kristal BS, Lampe JW, Hullar M, Shepherd J, Loo LLM, Ernst T, Franke AA, Tiirikainen M, Haiman CA, Stram DO, Le Marchand L, Cheng I. Genome-Wide Association Study of Liver Fat: The Multiethnic Cohort Adiposity Phenotype Study. Hepatol Commun 2020; 4:1112-1123. [PMID: 32766472 PMCID: PMC7395069 DOI: 10.1002/hep4.1533] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 03/20/2020] [Accepted: 04/02/2020] [Indexed: 12/13/2022] Open
Abstract
The global rise in fatty liver is a major public health problem. Thus, it is critical to identify both global and population-specific genetic variants associated with liver fat. We conducted a genome-wide association study (GWAS) of percent liver fat and nonalcoholic fatty liver disease (NAFLD) assessed by magnetic resonance imaging in 1,709 participants from the population-based Multiethnic Cohort Adiposity Phenotype Study. Our participants comprised older adults of five U.S. racial/ethnic groups: African Americans (n = 277), Japanese Americans (n = 424), Latinos (n = 348), Native Hawaiians (n = 274), and European Americans (n = 386). The established missense risk variant rs738409 located in patatin-like phospholipase domain containing 3 (PNPLA3) at 22q13 was confirmed to be associated with percent liver fat (P = 3.52 × 10-15) but more strongly in women than men (P heterogeneity = 0.002). Its frequency correlated with the prevalence of NAFLD across the five ethnic/racial groups. Rs738409 was also associated with homeostasis model assessment of insulin resistance (HOMA-IR) (beta = 0.028; P = 0.009) and circulating levels of insulin (beta = 0.022; P = 0.020) and alanine aminotransferase (beta = 0.016; P = 0.030). A novel association of percent liver fat with rs77249491 (located at 6q13 between limb region 1 domain containing 1 [LMBRD1] and collagen type XIX alpha 1 chain [COL19A1] (P = 1.42 × 10-8) was also observed. Rs7724941 was associated with HOMA-IR (beta = 0.12; P = 0.0005), insulin (beta = 0.11; P = 0.0003), triglycerides (beta = 0.059; P = 0.01), high-density lipoprotein (beta = -0.046; P = 0.04), and sex hormone binding globulin (beta = -0.084; P = 0.0012). This variant was present in Japanese Americans (minor allele frequency [MAF], 8%) and Native Hawaiians (MAF, 2%). Conclusion: We replicated the PNPLA3 rs738409 association in a multiethnic population and identified a novel liver fat risk variant in Japanese Americans and Native Hawaiians. GWASes of percent liver fat in East Asian and Oceanic populations are needed to replicate the rs77249491 association.
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Affiliation(s)
- S. Lani Park
- Keck School of MedicineUniversity of Southern CaliforniaLos AngelesCAUSA
| | - Yuqing Li
- Department of Epidemiology and BiostatisticsUniversity of California, San FranciscoSan FranciscoCAUSA
| | - Xin Sheng
- Keck School of MedicineUniversity of Southern CaliforniaLos AngelesCAUSA
| | - Victor Hom
- Keck School of MedicineUniversity of Southern CaliforniaLos AngelesCAUSA
| | - Lucy Xia
- Keck School of MedicineUniversity of Southern CaliforniaLos AngelesCAUSA
| | - Kechen Zhao
- Keck School of MedicineUniversity of Southern CaliforniaLos AngelesCAUSA
| | - Loreall Pooler
- Keck School of MedicineUniversity of Southern CaliforniaLos AngelesCAUSA
| | - V. Wendy Setiawan
- Keck School of MedicineUniversity of Southern CaliforniaLos AngelesCAUSA
| | - Unhee Lim
- University of Hawaii Cancer CenterUniversity of Hawaii at ManoaHonoluluHIUSA
| | - Kristine R. Monroe
- Keck School of MedicineUniversity of Southern CaliforniaLos AngelesCAUSA
| | - Lynne R. Wilkens
- University of Hawaii Cancer CenterUniversity of Hawaii at ManoaHonoluluHIUSA
| | - Bruce S. Kristal
- Division of Sleep and Circadian DisordersDepartment of MedicineBrigham and Women's HospitalBostonMAUSA
- Division of Sleep MedicineHarvard Medical SchoolBostonMAUSA
| | | | | | - John Shepherd
- University of Hawaii Cancer CenterUniversity of Hawaii at ManoaHonoluluHIUSA
| | - Lenora L. M. Loo
- University of Hawaii Cancer CenterUniversity of Hawaii at ManoaHonoluluHIUSA
| | - Thomas Ernst
- Department of Diagnostic Radiology and Nuclear MedicineUniversity of Maryland School of MedicineBaltimoreMDUSA
| | - Adrian A. Franke
- University of Hawaii Cancer CenterUniversity of Hawaii at ManoaHonoluluHIUSA
| | - Maarit Tiirikainen
- University of Hawaii Cancer CenterUniversity of Hawaii at ManoaHonoluluHIUSA
| | | | - Daniel O. Stram
- Keck School of MedicineUniversity of Southern CaliforniaLos AngelesCAUSA
| | - Loïc Le Marchand
- University of Hawaii Cancer CenterUniversity of Hawaii at ManoaHonoluluHIUSA
| | - Iona Cheng
- Department of Epidemiology and BiostatisticsUniversity of California, San FranciscoSan FranciscoCAUSA
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18
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Wang Y, Gunewardena S, Li F, Matye DJ, Chen C, Chao X, Jung T, Zhang Y, Czerwiński M, Ni HM, Ding WX, Li T. An FGF15/19-TFEB regulatory loop controls hepatic cholesterol and bile acid homeostasis. Nat Commun 2020; 11:3612. [PMID: 32681035 PMCID: PMC7368063 DOI: 10.1038/s41467-020-17363-6] [Citation(s) in RCA: 54] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Accepted: 06/26/2020] [Indexed: 12/15/2022] Open
Abstract
Bile acid synthesis plays a key role in regulating whole body cholesterol homeostasis. Transcriptional factor EB (TFEB) is a nutrient and stress-sensing transcriptional factor that promotes lysosomal biogenesis. Here we report a role of TFEB in regulating hepatic bile acid synthesis. We show that TFEB induces cholesterol 7α-hydroxylase (CYP7A1) in human hepatocytes and mouse livers and prevents hepatic cholesterol accumulation and hypercholesterolemia in Western diet-fed mice. Furthermore, we find that cholesterol-induced lysosomal stress feed-forward activates TFEB via promoting TFEB nuclear translocation, while bile acid-induced fibroblast growth factor 19 (FGF19), acting via mTOR/ERK signaling and TFEB phosphorylation, feedback inhibits TFEB nuclear translocation in hepatocytes. Consistently, blocking intestinal bile acid uptake by an apical sodium-bile acid transporter (ASBT) inhibitor decreases ileal FGF15, enhances hepatic TFEB nuclear localization and improves cholesterol homeostasis in Western diet-fed mice. This study has identified a TFEB-mediated gut-liver signaling axis that regulates hepatic cholesterol and bile acid homeostasis.
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Affiliation(s)
- Yifeng Wang
- Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS, 66160, USA
| | - Sumedha Gunewardena
- Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, KS, 66160, USA
| | - Feng Li
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, 77030, USA
| | - David J Matye
- Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS, 66160, USA
- Harold Hamm Diabetes Center, Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, 73104, USA
| | - Cheng Chen
- Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS, 66160, USA
| | - Xiaojuan Chao
- Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS, 66160, USA
| | - Taeyoon Jung
- Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS, 66160, USA
| | - Yuxia Zhang
- Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS, 66160, USA
| | | | - Hong-Min Ni
- Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS, 66160, USA
| | - Wen-Xing Ding
- Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS, 66160, USA
| | - Tiangang Li
- Harold Hamm Diabetes Center, Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, 73104, USA.
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Nascimbeni F, Dionisi Vici C, Vespasiani Gentilucci U, Angelico F, Nobili V, Petta S, Valenti L. AISF update on the diagnosis and management of adult-onset lysosomal storage diseases with hepatic involvement. Dig Liver Dis 2020; 52:359-367. [PMID: 31902560 DOI: 10.1016/j.dld.2019.12.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Revised: 12/07/2019] [Accepted: 12/10/2019] [Indexed: 12/11/2022]
Abstract
Lysosomal storage diseases (LSDs) are a heterogeneous group of inherited disorders caused by loss-of-function mutations in genes encoding for lysosomal enzymes/proteins. The consequence is a progressive accumulation of substrates in these intracellular organelles, resulting in cellular and tissue damage. The overall incidence is about 1/8000 live births, but is likely underestimated. LSDs are chronic progressive multi-systemic disorders, generally presenting with visceromegaly, and involvement of the central nervous system, eyes, the skeleton, and the respiratory and cardiovascular systems. The age at onset and phenotypic expression are highly variable, according to the specific enzymatic defect and tissues involved, the residual activity, and the disease-causing genotype. Enzyme-replacement therapies and substrate-reduction therapies have recently become available, leading to the improvement in symptoms, disease progression and quality of life of affected individuals. Liver involvement and hepatosplenomegaly are frequent features of LSDs and a hallmark of adult-onset forms, frequently leading to medical attention. LSDs should therefore be considered in the differential diagnosis of liver disease with organomegaly. The present document will provide a short overview of adult-onset LSDs with hepatic involvement, highlighting the specificities and systemic manifestations of the ones most frequently encountered in clinical practice, which may hint at the correct diagnosis and the appropriate treatment.
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Affiliation(s)
- Fabio Nascimbeni
- Regional Referral Centre for Lysosomal Storage Diseases, Division of Internal Medicine and Metabolism, Civil Hospital, AOU of Modena, University of Modena and Reggio Emilia, Modena, Italy
| | - Carlo Dionisi Vici
- Division of Metabolism, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | | | - Francesco Angelico
- Department of Public Health and Infective Diseases, Università Sapienza, Roma, Italy
| | - Valerio Nobili
- Division of Hepatology and Gastroenterology, Bambino Gesù Children's Hospital IRCCS, Rome, Italy
| | - Salvatore Petta
- Gastroenterology and Hepatology, PROMISE, Palermo University, Italy
| | - Luca Valenti
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, and Translational Medicine, Department of Transfusion Medicine and Hematology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy.
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20
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Baratta F, Pastori D, Tozzi G, D'Erasmo L, Di Costanzo A, Arca M, Ettorre E, Ginanni Corradini S, Violi F, Angelico F, Del Ben M. Lysosomal acid lipase activity and liver fibrosis in the clinical continuum of non-alcoholic fatty liver disease. Liver Int 2019; 39:2301-2308. [PMID: 31392821 DOI: 10.1111/liv.14206] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Revised: 07/15/2019] [Accepted: 07/26/2019] [Indexed: 12/16/2022]
Abstract
BACKGROUND AND AIMS Recent evidence showed a reduced activity of the lysosomal acid lipase (LAL) in patients with non-alcoholic fatty liver disease (NAFLD) and cryptogenic cirrhosis (CC). However, the relationship between LAL activity and liver fibrosis has never been investigated. METHODS Cross-sectional study including 575 outpatients referred for the management of cardio-metabolic and liver disease. The absence of liver fibrosis was defined by a FIB-4 < 1.30 and NAFLD fibrosis score (NFS) <-1.455. LAL activity was measured with dried blood spot technique. RESULTS Overall, 515 patients had a diagnosis of NAFLD (454 NAFL and 61 biopsy-proven NASH) and 60 of CC. The value of LAL activity progressively decreased from healthy subjects to NAFL/NASH patients to CC (P < .001). LAL activity was reduced by 10% in patients with NAFL, by 20% in NASH and by 50% in CC. The prevalence of CC decreased across the tertiles of LAL activity: 22.2% in the lowest, 4.6% in the intermediate and 0.5% in the highest tertile. In NAFLD patients, 69.9% had a FIB4 < 1.30, and 43.1% a NFS <-1.455. Multivariate logistic regression analysis showed that Log (LAL activity) was associated with FIB-4 < 1.30 (Odds ratio [OR] 2.19 95% confidence interval [CI] 1.33-3.62, P = .002) and NFS < -1.455 (OR 2.43, 95% CI 1.51-3.91, P < .001) after adjustment for confounding factors. CONCLUSIONS We found a progressive reduction of LAL activity according to liver disease severity. LAL activity was inversely associated with markers of liver fibrosis in patients with NAFLD.
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Affiliation(s)
- Francesco Baratta
- I Clinica Medica, Department of Internal Medicine and Medical Specialties, Sapienza University of Rome, Rome, Italy.,Department of Anatomical Sciences, Histological, Legal Medical and Locomotor, Sapienza University of Rome, Rome, Italy
| | - Daniele Pastori
- I Clinica Medica, Department of Internal Medicine and Medical Specialties, Sapienza University of Rome, Rome, Italy
| | - Giulia Tozzi
- Hepatology, Gastroenterology and Nutrition Unit, IRCCS "Bambino Gesù" Children's Hospital, Rome, Italy
| | - Laura D'Erasmo
- I Clinica Medica, Department of Internal Medicine and Medical Specialties, Sapienza University of Rome, Rome, Italy
| | - Alessia Di Costanzo
- I Clinica Medica, Department of Internal Medicine and Medical Specialties, Sapienza University of Rome, Rome, Italy
| | - Marcello Arca
- I Clinica Medica, Department of Internal Medicine and Medical Specialties, Sapienza University of Rome, Rome, Italy
| | - Evaristo Ettorre
- Division of Gerontology, Department of Cardiovascular, Respiratory, Nephrologic, Anesthesiologic and Geriatric Sciences, Sapienza University, Rome, Italy
| | | | - Francesco Violi
- I Clinica Medica, Department of Internal Medicine and Medical Specialties, Sapienza University of Rome, Rome, Italy.,Mediterranea Cardiocentro, Naples, Italy
| | - Francesco Angelico
- Department of Public Health and Infectious Diseases, Sapienza University of Rome, Rome, Italy
| | - Maria Del Ben
- I Clinica Medica, Department of Internal Medicine and Medical Specialties, Sapienza University of Rome, Rome, Italy
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21
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Gomaraschi M, Fracanzani AL, Dongiovanni P, Pavanello C, Giorgio E, Da Dalt L, Norata GD, Calabresi L, Consonni D, Lombardi R, Branchi A, Fargion S. Lipid accumulation impairs lysosomal acid lipase activity in hepatocytes: Evidence in NAFLD patients and cell cultures. Biochim Biophys Acta Mol Cell Biol Lipids 2019; 1864:158523. [DOI: 10.1016/j.bbalip.2019.158523] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Revised: 08/27/2019] [Accepted: 09/05/2019] [Indexed: 12/23/2022]
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22
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Baratta F, Pastori D, Ferro D, Carluccio G, Tozzi G, Angelico F, Violi F, Del Ben M. Reduced lysosomal acid lipase activity: A new marker of liver disease severity across the clinical continuum of non-alcoholic fatty liver disease? World J Gastroenterol 2019; 25:4172-4180. [PMID: 31435171 PMCID: PMC6700703 DOI: 10.3748/wjg.v25.i30.4172] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Revised: 06/20/2019] [Accepted: 07/02/2019] [Indexed: 02/06/2023] Open
Abstract
Lysosomal acid lipase (LAL) plays a key role in intracellular lipid metabolism. Reduced LAL activity promotes increased multi-organ lysosomal cholesterol ester storage, as observed in two recessive autosomal genetic diseases, Wolman disease and Cholesterol ester storage disease. Severe liver steatosis and accelerated liver fibrosis are common features in patients with genetic LAL deficiency. By contrast, few reliable data are available on the modulation of LAL activity in vivo and on the epigenetic and metabolic factors capable of regulating its activity in subjects without homozygous mutations of the Lipase A gene. In the last few years, a less severe and non-genetic reduction of LAL activity was reported in children and adults with non-alcoholic fatty liver disease (NAFLD), suggesting a possible role of LAL reduction in the pathogenesis and progression of the disease. Patients with NAFLD show a significant, progressive reduction of LAL activity from simple steatosis to non-alcoholic steatohepatitis and cryptogenic cirrhosis. Among cirrhosis of different etiologies, those with cryptogenic cirrhosis show the most significant reductions of LAL activity. These findings suggest that the modulation of LAL activity may become a possible new therapeutic target for patients with more advanced forms of NAFLD. Moreover, the measurement of LAL activity may represent a possible new marker of disease severity in this clinical setting.
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Affiliation(s)
- Francesco Baratta
- Department of Internal Medicine and Medical Specialties, Sapienza - University of Rome, Rome 00155, Italy
| | - Daniele Pastori
- Department of Internal Medicine and Medical Specialties, Sapienza - University of Rome, Rome 00155, Italy
| | - Domenico Ferro
- Department of Internal Medicine and Medical Specialties, Sapienza - University of Rome, Rome 00155, Italy
| | - Giovanna Carluccio
- Department of Internal Medicine and Medical Specialties, Sapienza - University of Rome, Rome 00155, Italy
| | - Giulia Tozzi
- Hepatogastroenterology and Nutrition Unit - Pediatric Department, Bambino Gesù Children’s Hospital, Rome 00156, Italy
| | - Francesco Angelico
- Department of Public Health and Infectious Disease, Sapienza - University of Rome, Rome 00161, Italy
| | - Francesco Violi
- Department of Internal Medicine and Medical Specialties, Sapienza - University of Rome, Rome 00155, Italy
| | - Maria Del Ben
- Department of Internal Medicine and Medical Specialties, Sapienza - University of Rome, Rome 00155, Italy
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23
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Association between Lysosomal Dysfunction and Obesity-Related Pathology: A Key Knowledge to Prevent Metabolic Syndrome. Int J Mol Sci 2019; 20:ijms20153688. [PMID: 31357643 PMCID: PMC6696452 DOI: 10.3390/ijms20153688] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2019] [Revised: 07/25/2019] [Accepted: 07/26/2019] [Indexed: 02/06/2023] Open
Abstract
Obesity causes various health problems, such as type 2 diabetes, non-alcoholic fatty liver disease, and cardio- and cerebrovascular diseases. Metabolic organs, particularly white adipose tissue (WAT) and liver, are deeply involved in obesity. WAT contains many adipocytes with energy storage capacity and secretes adipokines depending on the obesity state, while liver plays pivotal roles in glucose and lipid metabolism. This review outlines and underscores the relationship between obesity and lysosomal functions, including lysosome biogenesis, maturation and activity of lysosomal proteases in WAT and liver. It has been revealed that obesity-induced abnormalities of lysosomal proteases contribute to inflammation and cellular senescence in adipocytes. Previous reports have demonstrated obesity-induced ectopic lipid accumulation in liver is associated with abnormality of lysosomal proteases as well as other lysosomal enzymes. These studies demonstrate that lysosomal dysfunction in WAT and liver underlies part of the obesity-related pathology, raising the possibility that strategies to modulate lysosomal function may be effective in preventing or treating the metabolic syndrome.
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24
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Pavanello C, Baragetti A, Branchi A, Grigore L, Castelnuovo S, Giorgio E, Catapano AL, Calabresi L, Gomaraschi M. Treatment with fibrates is associated with higher LAL activity in dyslipidemic patients. Pharmacol Res 2019; 147:104362. [PMID: 31330253 DOI: 10.1016/j.phrs.2019.104362] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 07/01/2019] [Accepted: 07/18/2019] [Indexed: 01/01/2023]
Abstract
Lysosomal acid lipase (LAL) is responsible for the hydrolysis of cholesteryl esters (CE) and triglycerides (TG) within the lysosomes; generated cholesterol and free fatty acids (FFA) are released in the cytosol where they can regulate their own synthesis and metabolism. When LAL is not active, as in case of genetic mutations, CE and TG accumulate in the lysosomal compartment, while the lack of release of cholesterol and FFA in the cytosol leads to an upregulation of their synthesis. Thus, LAL plays a central role in the intracellular homeostasis of lipids. Since there are no indications about the effect of different lipid-lowering agents on LAL activity, aim of the study was to address the relationship between LAL activity and the type of lipid-lowering therapy in a cohort of dyslipidemic patients. LAL activity was measured on dried blood spot from 120 patients with hypercholesterolemia or mixed dyslipidemia and was negatively correlated to LDL-cholesterol levels. Among enrolled patients, ninety-one were taking one or more lipid-lowering drugs, as statins, fibrates, ezetimibe and omega-3 polyunsaturated fatty acids. When patients were stratified according to the type of lipid-lowering treatment, i.e. untreated, taking statins or taking fibrates, LAL activity was significantly higher in those with fibrates, even after adjustment for sex, age, BMI, lipid parameters, liver function, metabolic syndrome, diabetes and statin use. In a subset of patients tested after 3 months of treatment with micronized fenofibrate, LAL activity raised by 21%; the increase was negatively correlated with baseline LAL activity. Thus, the use of fibrates is independently associated with higher LAL activity in dyslipidemic patients, suggesting that the positive effects of PPAR-α activation on cellular and systemic lipid homeostasis can also include an improved LAL activity.
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Affiliation(s)
- Chiara Pavanello
- Centro E. Grossi Paoletti, Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milan, Italy
| | - Andrea Baragetti
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milan, Italy; S.I.S.A. Center for the Study of Atherosclerosis, Bassini Hospital, Cinisello Balsamo, Italy
| | - Adriana Branchi
- Centro per lo Studio e la Prevenzione dell'Aterosclerosi, Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Dipartimento di Scienze Cliniche e di Comunità, Università degli Studi di Milano, Milan, Italy
| | - Liliana Grigore
- S.I.S.A. Center for the Study of Atherosclerosis, Bassini Hospital, Cinisello Balsamo, Italy
| | - Samuela Castelnuovo
- Centro Dislipidemie, Dipartimento Cardiotoracovascolare, ASST Grande Ospedale Metropolitano Niguarda, Milan, Italy
| | - Eleonora Giorgio
- Centro E. Grossi Paoletti, Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milan, Italy
| | - Alberico L Catapano
- Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milan, Italy; IRCCS Multimedica Hospital, Milan, Italy
| | - Laura Calabresi
- Centro E. Grossi Paoletti, Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milan, Italy
| | - Monica Gomaraschi
- Centro E. Grossi Paoletti, Dipartimento di Scienze Farmacologiche e Biomolecolari, Università degli Studi di Milano, Milan, Italy.
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Ministrini S, Calzini L, Nulli Migliola E, Ricci MA, Roscini AR, Siepi D, Tozzi G, Daviddi G, Martorelli EE, Paganelli MT, Lupattelli G. Lysosomal Acid Lipase as a Molecular Target of the Very Low Carbohydrate Ketogenic Diet in Morbidly Obese Patients: The Potential Effects on Liver Steatosis and Cardiovascular Risk Factors. J Clin Med 2019; 8:jcm8050621. [PMID: 31067824 PMCID: PMC6571559 DOI: 10.3390/jcm8050621] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Revised: 05/01/2019] [Accepted: 05/03/2019] [Indexed: 02/08/2023] Open
Abstract
A very low carbohydrate ketogenic diet (VLCKD) is an emerging technique to induce a significant, well-tolerated, and rapid loss of body weight in morbidly obese patients. The low activity of lysosomal acid lipase (LAL) could be involved in the pathogenesis of non-alcoholic fatty liver disease (NAFLD), which is a common feature in morbidly obese patients. Fifty-two obese patients suitable for a bariatric surgery intervention underwent a 25-day-long VLCKD. The biochemical markers of glucose and lipid metabolism, and flow-mediated dilation (FMD) of the brachial artery were measured before and after VLCKD. LAL activity was measured using the dried blood spot technique in 20 obese patients and in a control group of 20 healthy, normal-weight subjects. After VLCKD, we observed a significant reduction in body mass index, fasting glucose, insulinemia, and lipid profile parameters. No significant variation in FMD was observed. The number of patients with severe liver steatosis significantly decreased. LAL activity significantly increased, although the levels were not significantly different as compared to the control group. In conclusion, VLCKD induces the activity of LAL in morbidly obese subjects and reduces the secretion of all circulating lipoproteins. These effects could be attributed to the peculiar composition of the diet, which is particularly poor in carbohydrates and relatively rich in proteins.
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Affiliation(s)
- Stefano Ministrini
- Internal Medicine, Department of Medicine, Università degli Studi di Perugia, 06129 Perugia, Italy.
| | - Lucia Calzini
- Internal Medicine, Department of Medicine, Università degli Studi di Perugia, 06129 Perugia, Italy.
| | - Elisa Nulli Migliola
- Internal Medicine, Department of Medicine, Università degli Studi di Perugia, 06129 Perugia, Italy.
| | - Maria Anastasia Ricci
- Internal Medicine, Department of Medicine, Università degli Studi di Perugia, 06129 Perugia, Italy.
| | - Anna Rita Roscini
- Internal Medicine, Department of Medicine, Università degli Studi di Perugia, 06129 Perugia, Italy.
| | - Donatella Siepi
- Internal Medicine, Department of Medicine, Università degli Studi di Perugia, 06129 Perugia, Italy.
| | - Giulia Tozzi
- Hepatology, Gastroenterology and Nutrition Unit, IRCCS "Bambino Gesù" Children's Hospital, 00165 Rome, Italy.
| | - Giulia Daviddi
- Internal Medicine, Department of Medicine, Università degli Studi di Perugia, 06129 Perugia, Italy.
| | - Eva-Edvige Martorelli
- Internal Medicine, Department of Medicine, Università degli Studi di Perugia, 06129 Perugia, Italy.
| | | | - Graziana Lupattelli
- Internal Medicine, Department of Medicine, Università degli Studi di Perugia, 06129 Perugia, Italy.
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Kuloglu Z, Kansu A, Selbuz S, Kalaycı AG, Şahin G, Kirsaclioglu CT, Demirören K, Dalgıç B, Kasırga E, Önal Z, İşlek A. The Frequency of Lysosomal Acid Lipase Deficiency in Children With Unexplained Liver Disease. J Pediatr Gastroenterol Nutr 2019; 68:371-376. [PMID: 30540705 DOI: 10.1097/mpg.0000000000002224] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
OBJECTIVES Evidence suggests that lysosomal acid lipase deficiency (LAL-D) is often underdiagnosed because symptoms may be nonspecific. We aimed to investigate the prevalence of LAL-D in children with unexplained liver disease and to identify demographic and clinical features with a prospective, multicenter, cross-sectional study. METHODS Patients (aged 3 months-18 years) who had unexplained transaminase elevation, unexplained hepatomegaly or hepatosplenomegaly, obesity-unrelated liver steatosis, biopsy-proven cryptogenic fibrosis and cirrhosis, or liver transplantation for cryptogenic cirrhosis were enrolled. A Web-based electronic data collection system was used. LAL activity (nmol/punch/h) was measured using the dried blood spot method and classified as LAL-D (<0.02), intermediate (0.02-0.37) or normal (> 0.37). A second dried blood spot sample was obtained from patients with intermediate LAL activity for confirmation of the result. RESULTS A total of 810 children (median age 5.6 years) from 795 families were enrolled. The reasons for enrollment were unexplained transaminase elevation (62%), unexplained organomegaly (45%), obesity-unrelated liver steatosis (26%), cryptogenic fibrosis and cirrhosis (6%), and liver transplantation for cryptogenic cirrhosis (<1%). LAL activity was normal in 634 (78%) and intermediate in 174 (21%) patients. LAL-D was identified in 2 siblings aged 15 and 6 years born to unrelated parents. Dyslipidemia, liver steatosis, and mild increase in aminotransferases were common features in these patients. Moreover, the 15-year-old patient showed growth failure and microvesicular steatosis, portal inflammation, and bridging fibrosis in the liver biopsy. Based on 795 families, 2 siblings in the same family were identified as LAL-D cases, making the prevalence of LAL-D in this study population, 0.1% (0.125%-0.606%). In the repeated measurement (76/174), LAL activity remained at the intermediate level in 38 patients. CONCLUSIONS Overall, the frequency of LAL-D patients in this study (0.1%) suggests that LAL-D seems to be rare even in the selected high-risk population.
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Affiliation(s)
- Zarife Kuloglu
- Department of Pediatric Gastroenterology, Hepatology and Nutrition, Ankara University School of Medicine, Ankara
| | - Aydan Kansu
- Department of Pediatric Gastroenterology, Hepatology and Nutrition, Ankara University School of Medicine, Ankara
| | - Suna Selbuz
- Department of Pediatric Gastroenterology, Hepatology and Nutrition, Ankara University School of Medicine, Ankara
| | - Ayhan G Kalaycı
- Department of Pediatric Gastroenterology, Hepatology and Nutrition, Ondokuz Mayıs University, School of Medicine, Samsun
| | - Gülseren Şahin
- Department of Pediatric Gastroenterology, Hepatology and Nutrition, Dr. Sami Ulus Children's Hospital, Ankara
| | - Ceyda Tuna Kirsaclioglu
- Department of Pediatric Gastroenterology, Hepatology and Nutrition, Turkish Republic Health Ministry, Ankara Child Health Diseases, Haematology Oncology Training and Research Hospital, Ankara
| | - Kaan Demirören
- Department of of Pediatric Gastroenterology, Hepatology and Nutrition, Yuzuncu Yıl University, Faculty of Medicine, Van
| | - Buket Dalgıç
- Department of Pediatric Gastroenterology, Hepatology and Nutrition, Gazi University University, Faculty of Medicine, Ankara
| | - Erhun Kasırga
- Department of Pediatric Gastroenterology, Hepatology and Nutrition, Celal Bayar University Faculty of Medicine, Manisa
| | - Zerrin Önal
- Department of Pediatric Gastroenterology, Hepatology and Nutrition, University of Medical Sciences, Bakırkoy Dr Sadi Konuk Research and Training Center, İstanbul
| | - Ali İşlek
- Department of Pediatric Gastroenterology, Hepatology and Nutrition, Atatürk University, Faculty of Medicine, Erzurum, Turkey
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Leopold C, Duta-Mare M, Sachdev V, Goeritzer M, Maresch LK, Kolb D, Reicher H, Wagner B, Stojakovic T, Ruelicke T, Haemmerle G, Hoefler G, Sattler W, Kratky D. Hepatocyte-specific lysosomal acid lipase deficiency protects mice from diet-induced obesity but promotes hepatic inflammation. Biochim Biophys Acta Mol Cell Biol Lipids 2019; 1864:500-511. [PMID: 30639734 PMCID: PMC6372077 DOI: 10.1016/j.bbalip.2019.01.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 12/20/2018] [Accepted: 01/06/2019] [Indexed: 12/21/2022]
Abstract
Lysosomal acid lipase (LAL) hydrolyzes cholesteryl esters (CE) and triglycerides (TG) to generate fatty acids (FA) and cholesterol. LAL deficiency (LAL-D) in both humans and mice leads to hepatomegaly, hypercholesterolemia, and shortened life span. Despite its essential role in lysosomal neutral lipid catabolism, the cell type-specific contribution of LAL to disease progression is still elusive. To investigate the role of LAL in the liver in more detail and to exclude the contribution of LAL in macrophages, we generated hepatocyte-specific LAL-deficient mice (Liv-Lipa−/−) and fed them either chow or high fat/high cholesterol diets (HF/HCD). Comparable to systemic LAL-D, Liv-Lipa−/− mice were resistant to diet-induced obesity independent of food intake, movement, and energy expenditure. Reduced body weight gain was mainly due to reduced white adipose tissue depots. Furthermore, Liv-Lipa−/− mice exhibited improved glucose clearance during glucose and insulin tolerance tests compared to control mice. Analysis of hepatic lipid content revealed a massive reduction of TG, whereas CE concentrations were markedly increased, leading to CE crystal formation in the livers of Liv-Lipa−/− mice. Elevated plasma transaminase activities, increased pro-inflammatory cytokines and chemokines as well as hepatic macrophage infiltration indicated liver inflammation. Our data provide evidence that hepatocyte-specific LAL deficiency is sufficient to alter whole-body lipid and energy homeostasis in mice. We conclude that hepatic LAL plays a pivotal role by preventing liver damage and maintaining lipid and energy homeostasis, especially during high lipid availability.
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Affiliation(s)
- Christina Leopold
- Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria
| | - Madalina Duta-Mare
- Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria
| | - Vinay Sachdev
- Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria
| | | | | | - Dagmar Kolb
- Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria; Center for Medical Research, Medical University of Graz, Graz, Austria
| | - Helga Reicher
- Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria
| | - Bettina Wagner
- Institute of Laboratory Animal Science, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Tatjana Stojakovic
- Clinical Institute of Medical and Chemical Laboratory Diagnostics, Medical University of Graz, Graz, Austria
| | - Thomas Ruelicke
- Institute of Laboratory Animal Science, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Guenter Haemmerle
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Gerald Hoefler
- Diagnostic and Research Institute of Pathology, Medical University of Graz, Graz, Austria; BioTechMed-Graz, Graz, Austria
| | - Wolfgang Sattler
- Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria; BioTechMed-Graz, Graz, Austria
| | - Dagmar Kratky
- Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria; BioTechMed-Graz, Graz, Austria.
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Carter A, Brackley SM, Gao J, Mann JP. The global prevalence and genetic spectrum of lysosomal acid lipase deficiency: A rare condition that mimics NAFLD. J Hepatol 2019; 70:142-150. [PMID: 30315827 DOI: 10.1016/j.jhep.2018.09.028] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2018] [Revised: 09/13/2018] [Accepted: 09/27/2018] [Indexed: 12/16/2022]
Abstract
BACKGROUND & AIMS Lysosomal acid lipase deficiency (LAL-D) is an autosomal recessive condition that may present in a mild form (cholesteryl ester storage disease [CESD]), which mimics non-alcoholic fatty liver disease (NAFLD). It has been suggested that CESD may affect 1 in 40,000 and is under-diagnosed in NAFLD clinics. Therefore, we aimed to estimate the prevalence of LAL-D using analysis of genetic variation in LIPA. METHODS MEDLINE and EMBASE were systematically searched for previously reported disease variants and prevalence estimates. Previous prevalence estimates were meta-analysed. Disease variants in LIPA were annotated with allele frequencies from gnomAD and combined with unreported major functional variants found in humans. Pooled ethnicity-specific prevalences for LAL-D and CESD were calculated using the Hardy-Weinberg equation. RESULTS Meta-analysis of existing genetic studies estimated the prevalence of LAL-D as 1 per 160,000 (95% CI 1 per 65,025-761,652) using the allele frequency of c.894G>A in LIPA. A total of 98 previously reported disease variants in LIPA were identified, of which 32/98 were present in gnomAD, giving a prevalence of 1 per 307,482 (95% CI 257,672-366,865). Wolman disease was associated with more loss-of-function variants than CESD. When this was combined with 22 previously unreported major functional variants in LIPA identified in humans, the pooled prevalence of LAL-D was 1 per 177,452 (95% CI 149,467-210,683) with a carrier frequency of 1 per 421. The prevalence is lowest in those of East Asian, South Asian, and Finnish ancestry. CONCLUSION Using 120 disease variants in LIPA, these data can reassure clinicians that LAL-D is an ultra-rare disorder. Given the therapeutic capability of sebelipase alpha, investigation for LAL-D might be included in second-line metabolic screening in NAFLD. LAY SUMMARY Lysosomal Acid Lipase Deficiency (LAL-D) is a rare genetic condition that can cause severe liver disease, but it is difficult to diagnose and sometimes can look like simple fatty liver. It was not clear how common LAL-D was and whether many cases were being missed. To study this, we searched for all genetic mutations that could cause LAL-D, calculated how common those mutations were, and added them up. This let us estimate that LAL-D affects roughly 1 in 175,000 people. We conclude that LAL-D is a very rare condition, but it is treatable so may be included in a 'second-line' of tests for causes of fatty liver.
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Affiliation(s)
- Anna Carter
- Manchester University Foundation Trust, Manchester, United Kingdom
| | - Simon Mark Brackley
- University of Cambridge, School of Clinical Medicine, Cambridge, United Kingdom
| | - Jiali Gao
- University of Cambridge, School of Clinical Medicine, Cambridge, United Kingdom
| | - Jake Peter Mann
- University of Cambridge, Department of Paediatrics, Cambridge, United Kingdom; University of Cambridge, Institute of Metabolic Science-Metabolic Research Laboratories, Cambridge, United Kingdom.
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29
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Gravito-Soares M, Gravito-Soares E, Gomes D, Tome L. Lysosomal Acid Lipase: Can it be a New Non-Invasive Serum Biomarker of Cryptogenic Liver Fibrosis and Cirrhosis? Ann Hepatol 2019; 18:78-88. [PMID: 31113613 DOI: 10.5604/01.3001.0012.7865] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2017] [Accepted: 01/10/2018] [Indexed: 02/04/2023]
Abstract
INTRODUCTION AND AIM The association between lysosomal acid lipase (LAL) activity and liver steatosis or fibrosis is poorly studied. The aim of our study was to determine the predictive power of LAL for cryptogenic liver steatosis and cryptogenic significant fibrosis/cirrhosis. MATERIAL AND METHODS Cross-sectional observational study of 101 adult patients with unexplained elevated liver enzymes/hepatomegaly with or without dyslipidemia submitted to the determination of LAL activity and LIPA gene (E8SJM-C.894G^A) mutation. Seventy-one patients underwent liver biopsy or FibroScan®. Patients with an identifiable liver dysfunction cause and well-stablished NAFLD/NASH risk factors were excluded. Predictors for liver steatosis, significant fibrosis (> F2) or cirrhosis (F4) were evaluated. RESULTS Liver steatosis and fibrosis were mainly assessed by liver biopsy (74.6%; n = 53). Steatosis was present in 62.0% (n = 44), significant fibrosis in 47.9% (n = 34) and cirrhosis in 39.4% (n = 28). The median LAL was 0.36 (0.21-0.46)nmol/spot/h (vs. 0.29 (0.20-0.47); p = 0.558) for liver steatosis, 0.22 (0.11-0.29) nmol/spot/h (vs. 0.40 (0.34-0.51); p <0.001) for significant fibrosis and 0.21 (0.11-0.27) nmol/spot/h (vs. 0.40 (0.32-0.52); p < 0.001) for cirrhosis. No LIPA gene mutations were found. LAL activity was the strongest predictor of significant fibrosis (AUROC: 0.833; p < 0.001) with a cut-off of 0.265 (sensitivity: 85.9%; specificity: 75.0%) and cirrhosis (AUROC: 0.859; p < 0.001) with a cut-off of 0.235 (sensitivity: 86.2%; specificity: 75.0%), being higher than FIB4, GUCI or APRI. However, LAL activity was not associated with liver steatosis (AUROC: 0.536; p =0.558). CONCLUSION LAL activity can be considered a non-invasive new marker of cryptogenic liver fibrosis with higher accuracy than other known biomarkers. LAL activity < 0.265 nmol/spot/h was strongly associated with cryptogenic significant fibrosis and <0.235 nmol/spot/h with cryptogenic cirrhosis. LAL activity was not associated with cryptogenic liver steatosis.
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Affiliation(s)
- Marta Gravito-Soares
- Department of Gastroenterology, Centro Hospitalar e Universitario de Coimbra, Coimbra, Portugal; Faculty of Medicine, University of Coimbra, Coimbra, Portugal; Authors contributed equally to this work.
| | - Elisa Gravito-Soares
- Department of Gastroenterology, Centro Hospitalar e Universitario de Coimbra, Coimbra, Portugal; Faculty of Medicine, University of Coimbra, Coimbra, Portugal; Authors contributed equally to this work
| | - Dario Gomes
- Department of Gastroenterology, Centro Hospitalar e Universitario de Coimbra, Coimbra, Portugal; Faculty of Medicine, University of Coimbra, Coimbra, Portugal
| | - Luis Tome
- Department of Gastroenterology, Centro Hospitalar e Universitario de Coimbra, Coimbra, Portugal; Faculty of Medicine, University of Coimbra, Coimbra, Portugal
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30
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Bessone F, Razori MV, Roma MG. Molecular pathways of nonalcoholic fatty liver disease development and progression. Cell Mol Life Sci 2019; 76:99-128. [PMID: 30343320 PMCID: PMC11105781 DOI: 10.1007/s00018-018-2947-0] [Citation(s) in RCA: 325] [Impact Index Per Article: 65.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Revised: 10/10/2018] [Accepted: 10/15/2018] [Indexed: 02/06/2023]
Abstract
Nonalcoholic fatty liver disease (NAFLD) is a main hepatic manifestation of metabolic syndrome. It represents a wide spectrum of histopathological abnormalities ranging from simple steatosis to nonalcoholic steatohepatitis (NASH) with or without fibrosis and, eventually, cirrhosis and hepatocellular carcinoma. While hepatic simple steatosis seems to be a rather benign manifestation of hepatic triglyceride accumulation, the buildup of highly toxic free fatty acids associated with insulin resistance-induced massive free fatty acid mobilization from adipose tissue and the increased de novo hepatic fatty acid synthesis from glucose acts as the "first hit" for NAFLD development. NAFLD progression seems to involve the occurrence of "parallel, multiple-hit" injuries, such as oxidative stress-induced mitochondrial dysfunction, endoplasmic reticulum stress, endotoxin-induced, TLR4-dependent release of inflammatory cytokines, and iron overload, among many others. These deleterious factors are responsible for the triggering of a number of signaling cascades leading to inflammation, cell death, and fibrosis, the hallmarks of NASH. This review is aimed at integrating the overwhelming progress made in the characterization of the physiopathological mechanisms of NAFLD at a molecular level, to better understand the factor influencing the initiation and progression of the disease.
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Affiliation(s)
- Fernando Bessone
- Hospital Provincial del Centenario, Facultad de Ciencias Médicas, Servicio de Gastroenterología y Hepatología, Universidad Nacional de Rosario, Rosario, Argentina
| | - María Valeria Razori
- Instituto de Fisiología Experimental (IFISE-CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 570, 2000, Rosario, Argentina
| | - Marcelo G Roma
- Instituto de Fisiología Experimental (IFISE-CONICET), Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 570, 2000, Rosario, Argentina.
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Diagnostic Algorithm for Cholesteryl Ester Storage Disease: Clinical Presentation in 19 Polish Patients. J Pediatr Gastroenterol Nutr 2018; 67:452-457. [PMID: 29958253 DOI: 10.1097/mpg.0000000000002084] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND Lysosomal acid lipase deficiency (LAL-D) is a rare autosomal recessive lysosomal lipid storage disorder that results in an early-onset, severe, and lethal phenotype, known as Wolman disease, or a late-onset, attenuated phenotype, cholesteryl ester storage disease (CESD). The aim of our study was to describe the clinical presentation of CESD, focusing on the first noted abnormalities in patients. A diagnostic algorithm of CESD was also proposed. METHODS This is an observational, 1-center study of 19 Polish patients with late-onset LAL-D. RESULTS The mean age at which the first symptoms were reported was 4 years and 6 months. A mild hepatomegaly was the most common initial abnormality observed in all (100%) patients. Seven (37%) patients were noted to have mildly to moderately elevated serum transaminases. At the time of first hospitalization all (100%) patients presented with hepatomegaly, 15 (79%) patients presented with elevated serum transaminases and all (100%) patients had dyslipidemia. The mean age at the time of CESD diagnosis was 7 years and 2 months. Diagnoses were based on a deficient LAL activity in leukocytes (in all patients) and the LIPA gene mutations (in 47% of them). All the patients were carriers for the mutation c.894G>A in the LIPA gene. There was approximately a 3-year delay from initial symptoms to final diagnosis. CONCLUSIONS Hepatomegaly constitutes the most common presenting clinical sign of CESD. Hepatomegaly and dyslipidemia defined as elevated serum total and LDL cholesterol, elevated triglycerides and normal to low HDL cholesterol, comprises the most characteristic findings at CESD diagnosis.
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Reynolds TM, Mewies C, Hamilton J, Wierzbicki AS. Identification of rare diseases by screening a population selected on the basis of routine pathology results-the PATHFINDER project: lysosomal acid lipase/cholesteryl ester storage disease substudy. J Clin Pathol 2018; 71:608-613. [PMID: 29358478 DOI: 10.1136/jclinpath-2017-204727] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Revised: 11/27/2017] [Accepted: 12/13/2017] [Indexed: 01/04/2023]
Abstract
AIMS Lysosomal acid lipase deficiency (LALD) is an autosomal recessive disorder of cholesterol ester storage associated with hepatic disease, cirrhosis and accelerated atherosclerosis. Its prevalence in the general population, patients with dyslipidaemia and raised transaminases is unclear. This study attempted to identify the prevalence of LALD from patients with abnormal results in laboratory databases. METHODS Electronic laboratory databases were interrogated to identify from clinical biochemistry records patients with a phenotype of low high-density lipoprotein-cholesterol (≤0.85 mmol/L; 33 mg/dL) and with elevated alanine or aspartate transaminases (≥60 IU/L) on one occasion or more over a 3-year time interval. Patients were recalled, and a dried blood spot sample was collected for lysosomal acid lipase determination by a fluorimetric enzyme assay. Histopathology databases of liver biopsies were interrogated for patients with features of 'microvesicular cirrhosis' or 'cryptogenic cirrhosis' in the report. Histological blocks were sampled, and samples were analysed by next-generation sequencing for the presence of mutations in the LAL gene. RESULTS Samples were obtained from 1825 patients with dyslipidaemia and elevated transaminases. No cases of LALD were identified. Liver biopsies were obtained from six patients. DNA extraction was successful from four patients. Two patients were homozygous for the LAL c.46A>C;p.Thr16Pro unclassified variant in exon 2. CONCLUSIONS Pathology databases hold routine information that can be used to identify patients with specific patterns of results or those who had biopsies to allow targeted testing for possible causes of disease. Biochemical screening suggests that the gene frequency of LAL deficiency in adults is less than 1 in 100.
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Affiliation(s)
- Timothy M Reynolds
- Department of Chemical Pathology, Queen's Hospital, Burton, UK
- Division of Health Sciences, Wolverhampton University, Wolverhampton, UK
| | - Clare Mewies
- Department of Chemical Pathology, Queen's Hospital, Burton, UK
| | - John Hamilton
- Biochemistry Department, Queen Elizabeth University Hospital Laboratory, Glasgow, UK
| | - Anthony S Wierzbicki
- Department of Metabolic Medicine/Chemical Pathology, Guy's & St Thomas' Hospitals, London, UK
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Wang Y, Ding WX, Li T. Cholesterol and bile acid-mediated regulation of autophagy in fatty liver diseases and atherosclerosis. Biochim Biophys Acta Mol Cell Biol Lipids 2018; 1863:726-733. [PMID: 29653253 PMCID: PMC6037329 DOI: 10.1016/j.bbalip.2018.04.005] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 03/22/2018] [Accepted: 04/08/2018] [Indexed: 12/19/2022]
Abstract
Liver is the major organ that regulates whole body cholesterol metabolism. Disrupted hepatic cholesterol homeostasis contributes to the pathogenesis of nonalcoholic steatohepatitis, dyslipidemia, atherosclerosis, and cardiovascular diseases. Hepatic bile acid synthesis is the major catabolic mechanism for cholesterol elimination from the body. Furthermore, bile acids are signaling molecules that regulate liver metabolism and inflammation. Autophagy is a highly-conserved lysosomal degradation mechanism, which plays an essential role in maintaining cellular integrity and energy homeostasis. In this review, we discuss emerging evidence linking hepatic cholesterol and bile acid metabolism to cellular autophagy activity in hepatocytes and macrophages, and how these interactions may be implicated in the pathogenesis and treatment of fatty liver disease and atherosclerosis.
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Affiliation(s)
- Yifeng Wang
- Department of Pharmacology, Toxicology and Therapeutics, The University of Kansas Medical Center, Kansas City, KS 66160, United States
| | - Wen-Xing Ding
- Department of Pharmacology, Toxicology and Therapeutics, The University of Kansas Medical Center, Kansas City, KS 66160, United States
| | - Tiangang Li
- Department of Pharmacology, Toxicology and Therapeutics, The University of Kansas Medical Center, Kansas City, KS 66160, United States.
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34
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Duta-Mare M, Sachdev V, Leopold C, Kolb D, Vujic N, Korbelius M, Hofer DC, Xia W, Huber K, Auer M, Gottschalk B, Magnes C, Graier WF, Prokesch A, Radovic B, Bogner-Strauss JG, Kratky D. Lysosomal acid lipase regulates fatty acid channeling in brown adipose tissue to maintain thermogenesis. Biochim Biophys Acta Mol Cell Biol Lipids 2018; 1863:467-478. [PMID: 29374543 DOI: 10.1016/j.bbalip.2018.01.011] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Revised: 01/02/2018] [Accepted: 01/22/2018] [Indexed: 02/07/2023]
Abstract
Lysosomal acid lipase (LAL) is the only known enzyme, which hydrolyzes cholesteryl esters and triacylglycerols in lysosomes of multiple cells and tissues. Here, we explored the role of LAL in brown adipose tissue (BAT). LAL-deficient (Lal-/-) mice exhibit markedly reduced UCP1 expression in BAT, modified BAT morphology with accumulation of lysosomes, and mitochondrial dysfunction, consequently leading to regular hypothermic events in mice kept at room temperature. Cold exposure resulted in reduced lipid uptake into BAT, thereby aggravating dyslipidemia and causing life threatening hypothermia in Lal-/- mice. Linking LAL as a potential regulator of lipoprotein lipase activity, we found Angptl4 mRNA expression upregulated in BAT. Our data demonstrate that LAL is critical for shuttling fatty acids derived from circulating lipoproteins to BAT during cold exposure. We conclude that inhibited lysosomal lipid hydrolysis in BAT leads to impaired thermogenesis in Lal-/- mice.
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Affiliation(s)
- Madalina Duta-Mare
- Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria
| | - Vinay Sachdev
- Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria
| | - Christina Leopold
- Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria
| | - Dagmar Kolb
- Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria; Center for Medical Research, Medical University of Graz, Graz, Austria
| | - Nemanja Vujic
- Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria
| | - Melanie Korbelius
- Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria
| | - Dina C Hofer
- Institute of Biochemistry, Graz University of Technology, Graz, Austria
| | - Wenmin Xia
- Institute of Biochemistry, Graz University of Technology, Graz, Austria
| | - Katharina Huber
- Institute of Biochemistry, Graz University of Technology, Graz, Austria
| | - Martina Auer
- Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria
| | | | - Christoph Magnes
- Health, Bioanalytik und Metabolomics, Joanneum Research, Graz, Austria
| | - Wolfgang F Graier
- Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria; BioTechMed-Graz, Graz, Austria
| | - Andreas Prokesch
- Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria
| | - Branislav Radovic
- Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria; BioTechMed-Graz, Graz, Austria
| | - Juliane G Bogner-Strauss
- Institute of Biochemistry, Graz University of Technology, Graz, Austria; BioTechMed-Graz, Graz, Austria
| | - Dagmar Kratky
- Gottfried Schatz Research Center, Medical University of Graz, Graz, Austria; BioTechMed-Graz, Graz, Austria.
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The Transcriptomic Signature Of Disease Development And Progression Of Nonalcoholic Fatty Liver Disease. Sci Rep 2017; 7:17193. [PMID: 29222421 PMCID: PMC5722878 DOI: 10.1038/s41598-017-17370-6] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Accepted: 11/24/2017] [Indexed: 02/06/2023] Open
Abstract
A longitudinal molecular model of the development and progression of nonalcoholic fatty liver disease (NAFLD) over time is lacking. We have recently validated a high fat/sugar water-induced animal (an isogenic strain of C57BL/6 J:129S1/SvImJ mice) model of NAFLD that closely mimics most aspects of human disease. The hepatic transcriptome of such mice with fatty liver (8 weeks), steatohepatitis with early fibrosis (16–24 weeks) and advanced fibrosis (52 weeks) after initiation of the diet was evaluated and compared to mice on chow diet. Fatty liver development was associated with transcriptional activation of lipogenesis, FXR-RXR, PPAR-α mediated lipid oxidation and oxidative stress pathways. With progression to steatohepatitis, metabolic pathway activation persisted with additional activation of IL-1/inhibition of RXR, granulocyte diapedesis/adhesion, Fc macrophage activation, prothrombin activation and hepatic stellate cell activation. Progression to advanced fibrosis was associated with dampening of metabolic, oxidative stress and cell stress related pathway activation but with further Fc macrophage activation, cell death and turnover and activation of cancer-related networks. The molecular progression of NAFLD involves a metabolic perturbation which triggers subsequent cell stress and inflammation driving cell death and turnover. Over time, inflammation and fibrogenic pathways become dominant while in advanced disease an inflammatory-oncogenic profile dominates.
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36
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Polimeni L, Pastori D, Baratta F, Tozzi G, Novo M, Vicinanza R, Troisi G, Pannitteri G, Ceci F, Scardella L, Violi F, Angelico F, Del Ben M. Spleen dimensions are inversely associated with lysosomal acid lipase activity in patients with non-alcoholic fatty liver disease. Intern Emerg Med 2017; 12:1159-1165. [PMID: 28900817 DOI: 10.1007/s11739-017-1746-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Accepted: 09/04/2017] [Indexed: 12/28/2022]
Abstract
Fatty liver and splenomegaly are typical features of genetic lysosomal acid lipase (LAL) deficiency. No data in adult patients with non-genetic reduction of LAL activity are available. We investigate the association between spleen dimensions and LAL activity in non-alcoholic fatty liver disease (NAFLD) patients, in whom a reduced LAL activity has been reported. We include 425 consecutive patients who underwent abdominal ultrasound to evaluate hepatic steatosis and spleen dimensions. LAL activity was measured with dried blood spot method (Lalistat2). NAFLD was present in 74.1% of screened patients. Higher median spleen longitudinal diameter (10.6 vs. 9.9 cm; p < 0.001) and spleen area (SA) (32.7 vs. 27.7 cm2; p < 0.001), together with a higher and proportion of splenomegaly (17.8 vs. 5.5%, p = 0.001), are present in patients with NAFLD compared to those without. In NAFLD patients, median LAL activity is 0.9 nmol/spot/h. LAL activity is lower in 56 patients with splenomegaly, as compared to those without (p = 0.009). At multivariable logistic regression analysis, age (above median, OR 0.344; p = 0.003), LAL activity (below median, OR 2.206, p = 0.028), and platelets (OR 0.101, p = 0.002) are significantly associated with splenomegaly. NAFLD patients disclose a relatively high prevalence of spleen enlargement and splenomegaly, which are significantly associated with a reduced LAL activity, suggesting that LAL may contribute to spleen enlargement in this setting.
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Affiliation(s)
- Licia Polimeni
- Department of Internal Medicine and Medical Specialties, Sapienza University, Rome, Italy
| | - Daniele Pastori
- Department of Internal Medicine and Medical Specialties, Sapienza University, Rome, Italy.
- Department of Anatomical, Histological, Forensic Medicine and Orthopedics Sciences, Sapienza University, Rome, Italy.
| | - Francesco Baratta
- Department of Internal Medicine and Medical Specialties, Sapienza University, Rome, Italy
- Department of Anatomical, Histological, Forensic Medicine and Orthopedics Sciences, Sapienza University, Rome, Italy
| | - Giulia Tozzi
- Unit for Neuromuscular and Neurodegenerative Diseases, Children's Hospital and Research Institute "Bambino Gesù", Rome, Italy
| | - Marta Novo
- Department of Internal Medicine and Medical Specialties, Sapienza University, Rome, Italy
| | - Roberto Vicinanza
- Department of Cardiovascular, Respiratory Nephrologic and Geriatric Sciences, Sapienza University of Rome, Rome, Italy
| | - Giovanni Troisi
- Department of Cardiovascular, Respiratory Nephrologic and Geriatric Sciences, Sapienza University of Rome, Rome, Italy
| | - Gaetano Pannitteri
- Department of Cardiovascular, Respiratory Nephrologic and Geriatric Sciences, Sapienza University of Rome, Rome, Italy
| | - Fabrizio Ceci
- Department of Cellular Biotechnologies and Hematology, Policlinico Umberto I Hospital, "La Sapienza" University, Rome, Italy
| | - Laura Scardella
- Department of Surgical Sciences, Sapienza University, Rome, Italy
| | - Francesco Violi
- Department of Internal Medicine and Medical Specialties, Sapienza University, Rome, Italy
| | - Francesco Angelico
- Department of Public Health and Infectious Diseases, Sapienza University, Rome, Italy
| | - Maria Del Ben
- Department of Internal Medicine and Medical Specialties, Sapienza University, Rome, Italy
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37
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Weiskirchen R. Fast progression of liver damage in lysosomal acid lipase deficiency. Curr Med Res Opin 2017; 33:2081-2083. [PMID: 28537522 DOI: 10.1080/03007995.2017.1335193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 05/23/2017] [Indexed: 10/19/2022]
Affiliation(s)
- Ralf Weiskirchen
- a Institute of Molecular Pathobiochemistry, Experimental Gene Therapy and Clinical Chemistry (IFMPEGKC), RWTH University Hospital Aachen , Aachen , Germany
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38
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Angelico F, Corradini SG, Pastori D, Fargion S, Fracanzani AL, Angelico M, Bolondi L, Tozzi G, Pujatti PL, Labbadia G, Corazza GR, Averna M, Perticone F, Croce G, Persico M, Bucci T, Baratta F, Polimeni L, Del Ben M, Violi F. Severe reduction of blood lysosomal acid lipase activity in cryptogenic cirrhosis: A nationwide multicentre cohort study. Atherosclerosis 2017; 262:179-184. [PMID: 28396038 DOI: 10.1016/j.atherosclerosis.2017.03.038] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 03/22/2017] [Accepted: 03/29/2017] [Indexed: 02/07/2023]
Abstract
BACKGROUND AND AIMS Blood lysosomal acid lipase (LAL) is reduced in non-alcoholic steatohepatitis, which is the major cause of cryptogenic cirrhosis (CC); few data on LAL activity in CC do exist. We investigated LAL activity in a cohort of patients with liver cirrhosis. METHODS This is a multicentre cohort study including 274 patients with liver cirrhosis of different aetiology from 19 centres of Internal Medicine, Gastroenterology and Hepatology distributed throughout Italy. Blood LAL activity (nmol/spot/h) was measured with dried blood spot extracts using Lalistat 2. RESULTS Overall, 133 patients had CC, and 141 patients had cirrhosis by other causes (61 viral, 53 alcoholic, 20 alcoholic + viral, 7 autoimmune). Mean age was 64.2 ± 13.4 years, and 28.5% were women. Patients with CC were older compared to other aetiology-cirrhosis, with a lower Child-Turcotte-Pugh (CTP, p=0.003) and MELD (p=0.009) score, and a higher prevalence of cardio-metabolic risk factors and previous ischemic events. In the whole cohort, median LAL activity value was 0.58 nmol/spot/h, 0.49 and 0.65 in the groups of CC and known-aetiology cirrhosis, respectively (p=0.002). The difference remained significant after adjustment for white blood cells count (p=0.001). Multivariable linear regression analysis showed that CC (vs. known aetiology, Beta = -0.144, p=0.018), platelet count (Beta = 0.398, p < 0.001) and CTP score (Beta = -0.133, p=0.022) were associated with log-LAL activity. Similar results were found using MELD as covariate. CONCLUSIONS We found a marked reduction of LAL activity in patients with cryptogenic cirrhosis compared to the other known aetiologies. A prospective study will clarify the role of LAL in chronic liver diseases.
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Affiliation(s)
- Francesco Angelico
- I Clinica Medica, Atherothrombosis Center, Department of Internal Medicine and Medical Specialties, Sapienza University of Rome, Italy; Department of Public Health and Infectious Diseases, Sapienza University of Rome, Italy.
| | | | - Daniele Pastori
- I Clinica Medica, Atherothrombosis Center, Department of Internal Medicine and Medical Specialties, Sapienza University of Rome, Italy; Department of Anatomical, Histological, Forensic Medicine and Orthopedics Sciences - Sapienza University of Rome, Italy
| | - Silvia Fargion
- Department of Pathophysiology and Transplantation, Ca' Granda Foundation IRCCS Maggiore Policlinico Hospital, University of Milan, Milan, Italy
| | - Anna Ludovica Fracanzani
- Department of Pathophysiology and Transplantation, Ca' Granda Foundation IRCCS Maggiore Policlinico Hospital, University of Milan, Milan, Italy
| | | | - Luigi Bolondi
- Department of Medical and Surgical Sciences, University of Bologna, Italy
| | - Giulia Tozzi
- Unit for Neuromuscular and Neurodegenerative Diseases, Children's Hospital and Research Institute "Bambino Gesù", Rome, Italy
| | - Pietro Luigi Pujatti
- Department of Internal Medicine, Ospedale di Arzignano, ULSS n.5 "Ovest Vicentino", Italy
| | - Giancarlo Labbadia
- I Clinica Medica, Atherothrombosis Center, Department of Internal Medicine and Medical Specialties, Sapienza University of Rome, Italy
| | - Gino Roberto Corazza
- First Department of Internal Medicine, Fondazione IRCCS Policlinico San Matteo, University of Pavia, Italy
| | - Maurizio Averna
- Department of Internal Medicine and Medical Specialties - DIBIMIS, School of Medicine, University of Palermo, Palermo, Italy
| | - Francesco Perticone
- Department of Medical and Surgical Sciences, University Magna Græcia of Catanzaro, Italy
| | - Giuseppe Croce
- Internal Medicine Unit, Giuseppe Mazzini Hospital, Teramo, Italy
| | - Marcello Persico
- Internal Medicine and Hepatology Unit, Salerno University of Medicine, Salerno, Italy
| | - Tommaso Bucci
- Internal Medicine and Hepatology Unit, Salerno University of Medicine, Salerno, Italy
| | - Francesco Baratta
- I Clinica Medica, Atherothrombosis Center, Department of Internal Medicine and Medical Specialties, Sapienza University of Rome, Italy; Department of Anatomical, Histological, Forensic Medicine and Orthopedics Sciences - Sapienza University of Rome, Italy
| | - Licia Polimeni
- I Clinica Medica, Atherothrombosis Center, Department of Internal Medicine and Medical Specialties, Sapienza University of Rome, Italy
| | - Maria Del Ben
- I Clinica Medica, Atherothrombosis Center, Department of Internal Medicine and Medical Specialties, Sapienza University of Rome, Italy
| | - Francesco Violi
- I Clinica Medica, Atherothrombosis Center, Department of Internal Medicine and Medical Specialties, Sapienza University of Rome, Italy
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Tovoli F, Napoli L, Negrini G, D'Addato S, Tozzi G, D'Amico J, Piscaglia F, Bolondi L. A Relative Deficiency of Lysosomal Acid Lypase Activity Characterizes Non-Alcoholic Fatty Liver Disease. Int J Mol Sci 2017; 18:E1134. [PMID: 28587063 PMCID: PMC5485958 DOI: 10.3390/ijms18061134] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Revised: 05/15/2017] [Accepted: 05/22/2017] [Indexed: 02/07/2023] Open
Abstract
Lysosomal acid lipase (LAL) is a key enzyme in lipid metabolism. Initial reports have suggested a role for a relative acquired LAL deficiency in non-alcoholic fatty liver disease (NAFLD)-however, it is still unclear whether this mechanism is specific for NAFLD. We aimed to determine LAL activity in a cohort of NAFLD subjects and in a control group of hepatitis C virus (HCV)-infected patients, investigating the role of liver cirrhosis. A total of 81 patients with a diagnosis of NAFLD, and 78 matched controls with HCV-related liver disease were enrolled. For each patient, LAL activity was determined on peripheral dried blood spots (DBS) and correlated with clinical and laboratory data. A subgroup analysis among cirrhotic patients was also performed. LAL activity is significantly reduced in NAFLD, compared to that in HCV patients. This finding is particularly evident in the pre-cirrhotic stage of disease. LAL activity is also correlated with platelet and white blood cell count, suggesting an analytic interference of portal-hypertension-induced pancytopenia on DBS-determined LAL activity. NAFLD is characterized by a specific deficit in LAL activity, suggesting a pathogenetic role of LAL. We propose that future studies on this topic should rely on tissue specific analyses, as peripheral blood tests are also influenced by confounding factors.
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Affiliation(s)
- Francesco Tovoli
- Unit of Internal Medicine, Departmentt of Medical and Surgical Sciences, University of Bologna, 40136 Bologna, Italy.
| | - Lucia Napoli
- Unit of Internal Medicine, Departmentt of Medical and Surgical Sciences, University of Bologna, 40136 Bologna, Italy.
| | - Giulia Negrini
- Unit of Internal Medicine, Departmentt of Medical and Surgical Sciences, University of Bologna, 40136 Bologna, Italy.
| | - Sergio D'Addato
- Unit of Internal Medicine, Departmentt of Medical and Surgical Sciences, University of Bologna, 40136 Bologna, Italy.
| | - Giulia Tozzi
- Unit of Neuromuscolar and Neurodegenerative Diseases, Children's Hospital and Research Institute "Bambino Gesù", 00165 Rome, Italy.
| | - Jessica D'Amico
- Unit of Neuromuscolar and Neurodegenerative Diseases, Children's Hospital and Research Institute "Bambino Gesù", 00165 Rome, Italy.
| | - Fabio Piscaglia
- Unit of Internal Medicine, Departmentt of Medical and Surgical Sciences, University of Bologna, 40136 Bologna, Italy.
| | - Luigi Bolondi
- Unit of Internal Medicine, Departmentt of Medical and Surgical Sciences, University of Bologna, 40136 Bologna, Italy.
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40
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Block RC, Razani B. Linking lysosomal acid lipase insufficiency to the development of cryptogenic cirrhosis. Atherosclerosis 2017; 262:140-142. [PMID: 28502381 DOI: 10.1016/j.atherosclerosis.2017.04.018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Accepted: 04/21/2017] [Indexed: 01/21/2023]
Affiliation(s)
- Robert C Block
- Department of Public Health Sciences, Cardiology Division, University of Rochester School of Medicine and Dentistry, Rochester, NY 14618, USA; Department of Medicine, University of Rochester School of Medicine and Dentistry, Rochester, NY 14618, USA.
| | - Babak Razani
- Department of Medicine, Cardiovascular Division, Washington University School of Medicine, St. Louis, MO 63110, USA; Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA.
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41
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Chora JR, Alves AC, Medeiros AM, Mariano C, Lobarinhas G, Guerra A, Mansilha H, Cortez-Pinto H, Bourbon M. Lysosomal acid lipase deficiency: A hidden disease among cohorts of familial hypercholesterolemia? J Clin Lipidol 2017; 11:477-484.e2. [PMID: 28502505 DOI: 10.1016/j.jacl.2016.11.002] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Revised: 10/18/2016] [Accepted: 11/08/2016] [Indexed: 12/15/2022]
Abstract
BACKGROUND Lysosomal acid lipase deficiency (LALD) is an autosomal recessive disorder and an unrecognized cause of dyslipidemia. Patients usually present with dyslipidemia and altered liver function and mutations in LIPA gene are the underlying cause of LALD. OBJECTIVE The aim of this study was to investigate LALD in individuals with severe dyslipidemia and/or liver steatosis. METHODS Coding, splice regions, and promoter region of LIPA were sequenced by Sanger sequencing in a cohort of mutation-negative familial hypercholesterolemia (FH) patients (n = 492) and in a population sample comprising individuals with several types of dyslipidemia and/or liver steatosis (n = 258). RESULTS This study led to the identification of LALD in 4 children referred to the Portuguese FH Study, all with a clinical diagnosis of FH. Mild liver dysfunction was present at the age of FH diagnosis; however, a diagnosis of LALD was not considered. No adults at the time of referral have been identified with LALD. CONCLUSION LALD is a life-threatening disorder, and early identification is crucial for the implementation of specific treatment to avoid premature mortality. FH cohorts should be investigated to identify possible LALD patients, who will need appropriate treatment. These results highlight the importance of correctly identifying the etiology of the dyslipidemia.
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Affiliation(s)
- Joana Rita Chora
- Unidade I&D, Grupo de Investigação Cardiovascular, Departamento de Promoção da Saúde e Doenças Não Transmissíveis, Instituto Nacional de Saúde Doutor Ricardo Jorge, Lisboa, Portugal; University of Lisboa, Faculty of Sciences, BioISI-Biosystems & Integrative Sciences Institute, Campo Grande, Lisboa, Portugal
| | - Ana Catarina Alves
- Unidade I&D, Grupo de Investigação Cardiovascular, Departamento de Promoção da Saúde e Doenças Não Transmissíveis, Instituto Nacional de Saúde Doutor Ricardo Jorge, Lisboa, Portugal; University of Lisboa, Faculty of Sciences, BioISI-Biosystems & Integrative Sciences Institute, Campo Grande, Lisboa, Portugal
| | - Ana Margarida Medeiros
- Unidade I&D, Grupo de Investigação Cardiovascular, Departamento de Promoção da Saúde e Doenças Não Transmissíveis, Instituto Nacional de Saúde Doutor Ricardo Jorge, Lisboa, Portugal; University of Lisboa, Faculty of Sciences, BioISI-Biosystems & Integrative Sciences Institute, Campo Grande, Lisboa, Portugal
| | - Cibelle Mariano
- Unidade I&D, Grupo de Investigação Cardiovascular, Departamento de Promoção da Saúde e Doenças Não Transmissíveis, Instituto Nacional de Saúde Doutor Ricardo Jorge, Lisboa, Portugal; University of Lisboa, Faculty of Sciences, BioISI-Biosystems & Integrative Sciences Institute, Campo Grande, Lisboa, Portugal
| | - Goreti Lobarinhas
- Serviço de Pediatria, Hospital de Santa Maria Maior, Barcelos, Portugal
| | - António Guerra
- Serviço de Pediatria, Centro Hospitalar de São João, Porto, Portugal; Centro de Investigação em Tecnologias e Serviços de Saúde (CINTESIS), Faculdade de Medicina, Universidade do Porto, Porto, Portugal
| | - Helena Mansilha
- Serviço de Pediatria/Nutrição Pediátrica, Departamento da Infância e Adolescência, Centro Materno-Infantil do Norte (CMIN), Porto, Portugal
| | - Helena Cortez-Pinto
- Departamento de Gastrenterologia, Laboratório de Nutrição, Hospital Santa Maria, Faculdade de Medicina de Lisboa, Universidade de Lisboa, Portugal
| | - Mafalda Bourbon
- Unidade I&D, Grupo de Investigação Cardiovascular, Departamento de Promoção da Saúde e Doenças Não Transmissíveis, Instituto Nacional de Saúde Doutor Ricardo Jorge, Lisboa, Portugal; University of Lisboa, Faculty of Sciences, BioISI-Biosystems & Integrative Sciences Institute, Campo Grande, Lisboa, Portugal.
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Platelet count may impact on lysosomal acid lipase activity determination in dried blood spot. Clin Biochem 2017; 50:726-728. [PMID: 28238812 DOI: 10.1016/j.clinbiochem.2017.02.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 02/14/2017] [Accepted: 02/16/2017] [Indexed: 12/26/2022]
Abstract
BACKGROUND We aimed to evaluate the influence of white blood cell (WBC) and platelet (PLT) counts on dried blood spot (DBS)-determined lysosomal acid lipase (LAL) activity in a large group of healthy subjects. METHODS One-hundred-and-seventy-two healthy subjects aged ≥18 were enrolled. Complete clinical biochemistry and LAL activity in DBS were determined. In 35 subjects, WBCs and PLTs were isolated, and LAL activity was measured in both blood cell populations. Univariate and multivariate analyses to DBS-LAL activity were performed. RESULTS Mean age of subjects was 44.8±17.2years, 43.6% were males, and mean DBS-LAL activity was normal (1.0±0.3nmol/spot/h). LAL activity in WBCs was significantly higher than in PLTs (458.9±133.6 vs 235.0±88.3nmol/mg/h, p<0.001). However, LAL activity in DBS correlated more strongly with that in PLTs (r=0.65, p<0.001) than with that in WBCs (r=0.49, p<0.01). Consistently, in the multivariate model, DBS-LAL activity was independently associated only with PLT count (β=0.39, p<0.001). CONCLUSIONS PLT number may impact on the result of the DBS-LAL test, and a consideration of PLT count is recommended before interpreting LAL activity in DBS.
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Walenbergh SMA, Shiri-Sverdlov R. Cholesterol is a significant risk factor for non-alcoholic steatohepatitis. Expert Rev Gastroenterol Hepatol 2016; 9:1343-6. [PMID: 26395315 DOI: 10.1586/17474124.2015.1092382] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Non-alcoholic steatohepatitis (NASH) is characterized by hepatic lipid accumulation (steatosis) and inflammation (steatohepatitis). Currently, the exact underlying mechanisms leading to hepatic inflammation remain incompletely understood and therefore therapy options are poor. Analogous to the predominant metabolic risk factor for the metabolic syndrome, NASH patients often display diet-induced dyslipidemia and are therefore also at high risk for cardiovascular disease. Higher lipid levels, in general, are also widely associated with the production of reactive oxygen species during oxidation. However, the exact contribution of the specific type of lipids to hepatic inflammation still remains unclear. In this editorial, we aim to show that cholesterol, in addition to triglycerides and free fatty acids, is an important risk factor in NASH disease pathogenesis. Developing a better understanding of the contribution of lipids underlying NASH pathogenesis is essential for creating effective therapies against this prevalent disease.
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Affiliation(s)
- Sofie M A Walenbergh
- a Department of Molecular Genetics, School of Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University, Maastricht, The Netherlands
| | - Ronit Shiri-Sverdlov
- a Department of Molecular Genetics, School of Nutrition and Translational Research in Metabolism (NUTRIM), Maastricht University, Maastricht, The Netherlands
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Reduced lysosomal acid lipase activity - A potential role in the pathogenesis of non alcoholic fatty liver disease in pediatric patients. Dig Liver Dis 2016; 48:909-13. [PMID: 27198736 DOI: 10.1016/j.dld.2016.04.014] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Revised: 04/19/2016] [Accepted: 04/21/2016] [Indexed: 12/11/2022]
Abstract
BACKGROUND Within the spectrum of nonalcoholic fatty liver disease (NAFLD), recent evidence suggests that adult patients with nonalcoholic steatohepatitis (NASH) have significantly lower blood lysosomal acid lipase (LAL) activity than those with steatosis. This has not been studied in pediatric patients with NAFLD. AIM Investigate blood LAL activity in pediatric patients with NAFLD and assess its correlation with histological severity. METHODS We collected data on consecutive children with biopsy-proven NAFLD including demographics, anthropometrics, and routine laboratory tests. The histological features were graded according to the NAFLD activity scoring proposed by Kleiner et al. Blood LAL activity was measured prospectively using Lalistat 2. RESULTS A total of 168 children were included for analysis. Mean age was 12.6±8.5 years, 60.1% were males and 52.4% had NASH. Children with significant fibrosis (stage 2-3, n=64) had a significantly lower LAL activity compared to those with mild fibrosis (stage 0-1, n=104). There was no significant difference in LAL activity between children with NASH compared to those without NASH. CONCLUSION Reduced blood LAL activity correlates with severity of liver fibrosis in children with NAFLD indicating a potential role of reduced LAL activity in the pathogenesis of NAFLD-induced fibrosis.
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Lorbek G, Urlep Ž, Rozman D. Pharmacogenomic and personalized approaches to tackle nonalcoholic fatty liver disease. Pharmacogenomics 2016; 17:1273-1288. [PMID: 27377717 DOI: 10.2217/pgs-2016-0047] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Nonalcoholic fatty liver disease (NAFLD) is a raising liver disease with increasing prevalence due to the epidemics of obesity and diabetes, with end points in cirrhosis or hepatocellular carcinoma. A multitude of genetic and metabolic perturbations, together with environmental factors, likely drive the disease. However, to date only a few genes, primarily PNPLA3 and TM6SF2, associate with NAFLD and there is no specific treatment. In this review we focus on the therapeutical aspects of NAFLD, taking into account drugs and lifestyle interventions. Sex also influences disease progression and treatment outcomes. Lastly, we discuss the present and potential future of personalized approaches to tackle NAFLD and how the known polymorphisms of NAFLD associated genes influence the choice and success of therapy.
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Affiliation(s)
- Gregor Lorbek
- Faculty of Medicine, Center for Functional Genomics & Bio-Chips, Institute of Biochemistry, University of Ljubljana, Ljubljana, Slovenia
| | - Žiga Urlep
- Faculty of Medicine, Center for Functional Genomics & Bio-Chips, Institute of Biochemistry, University of Ljubljana, Ljubljana, Slovenia
| | - Damjana Rozman
- Faculty of Medicine, Center for Functional Genomics & Bio-Chips, Institute of Biochemistry, University of Ljubljana, Ljubljana, Slovenia
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Lysosomal Acid Lipase Activity Is Reduced Both in Cryptogenic Cirrhosis and in Cirrhosis of Known Etiology. PLoS One 2016; 11:e0156113. [PMID: 27219619 PMCID: PMC4878774 DOI: 10.1371/journal.pone.0156113] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Accepted: 05/09/2016] [Indexed: 12/11/2022] Open
Abstract
Lysosomal acid lipase deficiency (LAL-d) is a rare autosomal recessive disease in which LAL activity is almost absent, with consequent massive microvesicular steatosis evolving to cirrhosis and liver failure. We aimed to determine LAL-activity, and to investigate the most common single nucleotide polymorphism (SNP) affecting the LIPA gene and responsible for 50–70% of LAL-d cases (rs116928232 c.894G>A), in patients with cryptogenic cirrhosis. Sixty-three patients with cryptogenic cirrhosis, 88 cirrhotics of known etiology, and 97 healthy subjects were enrolled. LAL-activity was determined in dried-blood-spot (DBS). The c.894G>A mutation was analyzed by pyrosequencing method in SNP mode. LAL-activity was severely reduced in patients with cryptogenic cirrhosis with respect to healthy subjects [0.62 (0.44–0.86) Vs 0.96 (0.75–1.25) nmol/spot/h, p<0.001)], but it was also reduced in known-etiology cirrhotics [0.54 (0.42–0.79) nmol/spot/h, p<0.001 Vs healthy subjects; p = 0.5 Vs cryptogenic cirrhotics]. Fourteen percent of cryptogenic cirrhotics and 20% of known-etiology cirrhotics showed a LAL-activity in the range of heterozygous carriers of LIPA gene mutations (0.15–0.40 nmol/spot/h). However, none of the subjects with reduced LAL-activity carried the c.894G>A SNP except for one patient with HCV cirrhosis. By multivariate analysis, LAL-activity was not associated with age, sex, liver enzymes, liver function or lipid parameters, while it was independently associated with white blood cell (β = 0.2; p<0.01) and platelet (β = 0.4; p<0.001) counts and with the condition of cirrhosis (β = -0.2; p = 0.04).
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Shteyer E, Villenchik R, Mahamid M, Nator N, Safadi R. Low Serum Lysosomal Acid Lipase Activity Correlates with Advanced Liver Disease. Int J Mol Sci 2016; 17:312. [PMID: 26927097 PMCID: PMC4813175 DOI: 10.3390/ijms17030312] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2015] [Revised: 02/18/2016] [Accepted: 02/18/2016] [Indexed: 12/19/2022] Open
Abstract
Fatty liver has become the most common liver disorder and is recognized as a major health burden in the Western world. The causes for disease progression are not fully elucidated but lysosomal impairment is suggested. Here we evaluate a possible role for lysosomal acid lipase (LAL) activity in liver disease. To study LAL levels in patients with microvesicular, idiopathic cirrhosis and nonalcoholic fatty liver disease (NAFLD). Medical records of patients with microvesicular steatosis, cryptogenic cirrhosis and NAFLD, diagnosed on the basis of liver biopsies, were included in the study. Measured serum LAL activity was correlated to clinical, laboratory, imaging and pathological data. No patient exhibited LAL activity compatible with genetic LAL deficiency. However, serum LAL activity inversely predicted liver disease severity. A LAL level of 0.5 was the most sensitive for detecting both histologic and noninvasive markers for disease severity, including lower white blood cell count and calcium, and elevated γ-glutamyltransferase, creatinine, glucose, glycated hemoglobin, uric acid and coagulation function. Serum LAL activity <0.5 indicates severe liver injury in patients with fatty liver and cirrhosis. Further studies should define the direct role of LAL in liver disease severity and consider the possibility of replacement therapy.
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Affiliation(s)
- Eyal Shteyer
- The Liver Unit, Gastroenterology Institute, Hadassah Medical Center, Hadassah Medical School, The Hebrew University, Jerusalem 9112001, Israel.
- Pediatric Gastroenterology Institute, Shaare Zedek Medical Center, Hadassah Medical School, The Hebrew University, Jerusalem 9103102, Israel.
| | - Rivka Villenchik
- The Liver Unit, Gastroenterology Institute, Hadassah Medical Center, Hadassah Medical School, The Hebrew University, Jerusalem 9112001, Israel.
| | - Mahmud Mahamid
- Liver Unit, Gastroenterology Institute, Shaare Zedek Medical Center, Hadassah Medical School, The Hebrew University, Jerusalem 9112001, Israel.
- Liver Unit, Holy Family Hospital; Safed Medical School, Bar Ilan University, Nazareth 1641110, Israel.
| | - Nidaa Nator
- The Liver Unit, Gastroenterology Institute, Hadassah Medical Center, Hadassah Medical School, The Hebrew University, Jerusalem 9112001, Israel.
| | - Rifaat Safadi
- The Liver Unit, Gastroenterology Institute, Hadassah Medical Center, Hadassah Medical School, The Hebrew University, Jerusalem 9112001, Israel.
- Liver Unit, Holy Family Hospital; Safed Medical School, Bar Ilan University, Nazareth 1641110, Israel.
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Zhang LD, Wei W, Sun XH, Song YL, Feng XZ, Jiang M. Cross-sectional study of Chinese medicine disease, constitution and syndrome of nonalcoholic fatty liver disease. Shijie Huaren Xiaohua Zazhi 2015; 23:5296-5302. [DOI: 10.11569/wcjd.v23.i33.5296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To study the feature of Chinese medicine disease, constitution and syndrome of nonalcoholic fatty liver disease (NAFLD).
METHODS: The investigation was based on a cross-sectional epidemiological method. NAFLD subjects treated at Department of Gastroenterology, Acupuncture and Moxibustion, or Orthopaedics, Wangjing Hospital, China Academy of Chinese Medical Sciences were used to assess the Chinese medicine disease, constitution and syndrome of NAFLD.
RESULTS: A total of 98 NAFLD subjects were included for statistical analysis. Overall, microcosmic Chinese medicine information including the liver function, blood fat, biochemistry, and blood routine examinations showed no significant abnormality in most of the subjects. Phlegmatic hygrosis was found in 34.7% of all NAFLD subjects, damp heat was found in 16.3%, blood stasis in 16.3%, depressed vital energy in 10.2%, yang asthenia in 6.1%, equilibration in 6.1%, vital energy deficiency in 3.1%, and damp heat with blood stasis in 3.1%. Syndrome differentiation showed retention of phlegmatic dampness in 31.6% of all NAFLD subjects, stagnation of damp heat in 23.5%, phlegm accumulation with stagnant blood in 20.4%, turbi damp obstruction in viscus in 13.3%, stagnation of vital energy due to depression of the liver in 8.2%, and stagnation of liver vital energy with deficiency of the spleen syndrome in 3.1%.
CONCLUSION: Syndrome elements of NAFLD mainly include dampness, heat, phlegm, and blood stasis. Phlegmatic hygrosis, damp heat, blood stasis and their combinations are the manifestations of NAFLD syndrome elements. Retention of phlegmatic dampness, stagnation of damp heat, phlegm accumulation with stagnant blood, and turbi damp obstruction in viscus are the main syndromes of NAFLD. There is no specific index for sufficient NAFLD evaluation.
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Baratta F, Pastori D, Polimeni L, Tozzi G, Violi F, Angelico F, Del Ben M. Does Lysosomial Acid Lipase Reduction Play a Role in Adult Non-Alcoholic Fatty Liver Disease? Int J Mol Sci 2015; 16:28014-21. [PMID: 26602919 PMCID: PMC4691032 DOI: 10.3390/ijms161226085] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Revised: 11/06/2015] [Accepted: 11/17/2015] [Indexed: 12/15/2022] Open
Abstract
Lysosomal Acid Lipase (LAL) is a key enzyme involved in lipid metabolism, responsible for hydrolysing the cholesteryl esters and triglycerides. Wolman Disease represents the early onset phenotype of LAL deficiency rapidly leading to death. Cholesterol Ester Storage Disease is a late onset phenotype that occurs with fatty liver, elevated aminotransferase levels, hepatomegaly and dyslipidaemia, the latter characterized by elevated LDL-C and low HDL-C. The natural history and the clinical manifestations of the LAL deficiency in adults are not well defined, and the diagnosis is often incidental. LAL deficiency has been suggested as an under-recognized cause of dyslipidaemia and fatty liver. Therefore, LAL activity may be reduced also in non-obese patients presenting non-alcoholic fatty liver disease (NAFLD), unexplained persistently elevated liver transaminases or with elevation in LDL cholesterol. In these patients, it could be indicated to test LAL activity. So far, very few studies have been performed to assess LAL activity in representative samples of normal subjects or patients with NAFLD. Moreover, no large study has been carried out in adult subjects with NAFLD or cryptogenic cirrhosis.
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Affiliation(s)
- Francesco Baratta
- Department of Internal Medicine and Medical Specialities and Department of Anatomical, Histological, Forensic Medicine and Orthopedics Sciences-Sapienza University, Rome 00185, Italy.
| | - Daniele Pastori
- Department of Internal Medicine and Medical Specialities and Department of Anatomical, Histological, Forensic Medicine and Orthopedics Sciences-Sapienza University, Rome 00185, Italy.
| | - Licia Polimeni
- Department of Internal Medicine and Medical Specialities and Department of Anatomical, Histological, Forensic Medicine and Orthopedics Sciences-Sapienza University, Rome 00185, Italy.
| | - Giulia Tozzi
- Unit for Neuromuscular and Neurodegenerative Diseases, Children's Hospital and Research Institute "Bambino Gesù", Rome 00165, Italy.
| | - Francesco Violi
- Department of Internal Medicine and Medical Specialities, Sapienza University, Rome 00185, Italy.
| | - Francesco Angelico
- Department of Public Health and Infectious Diseases, Sapienza University, Policlinico Umberto I, I Clinica Medica, Viale del Policlinico 155, Rome 00161, Italy.
| | - Maria Del Ben
- Department of Internal Medicine and Medical Specialities, Sapienza University, Rome 00185, Italy.
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50
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Ramirez CM, Lopez AM, Turley SD. Lysosomal Acid Lipase Activity: A Tool for the Detection and Management of Fatty Liver Disease? EBioMedicine 2015; 2:638-9. [PMID: 26286464 PMCID: PMC4534703 DOI: 10.1016/j.ebiom.2015.06.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Accepted: 06/08/2015] [Indexed: 12/11/2022] Open
Affiliation(s)
- Charina M Ramirez
- Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Adam M Lopez
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Stephen D Turley
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, USA
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