1
|
Okamura T, Tsukamoto K, Arai H, Fujioka Y, Ishigaki Y, Koba S, Ohmura H, Shoji T, Yokote K, Yoshida H, Yoshida M, Deguchi J, Dobashi K, Fujiyoshi A, Hamaguchi H, Hara M, Harada-Shiba M, Hirata T, Iida M, Ikeda Y, Ishibashi S, Kanda H, Kihara S, Kitagawa K, Kodama S, Koseki M, Maezawa Y, Masuda D, Miida T, Miyamoto Y, Nishimura R, Node K, Noguchi M, Ohishi M, Saito I, Sawada S, Sone H, Takemoto M, Wakatsuki A, Yanai H. Japan Atherosclerosis Society (JAS) Guidelines for Prevention of Atherosclerotic Cardiovascular Diseases 2022. J Atheroscler Thromb 2024; 31:641-853. [PMID: 38123343 DOI: 10.5551/jat.gl2022] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2023] Open
Affiliation(s)
- Tomonori Okamura
- Preventive Medicine and Public Health, Keio University School of Medicine
| | | | | | - Yoshio Fujioka
- Faculty of Nutrition, Division of Clinical Nutrition, Kobe Gakuin University
| | - Yasushi Ishigaki
- Division of Diabetes, Metabolism and Endocrinology, Department of Internal Medicine, Iwate Medical University
| | - Shinji Koba
- Division of Cardiology, Department of Medicine, Showa University School of Medicine
| | - Hirotoshi Ohmura
- Department of Cardiovascular Biology and Medicine, Juntendo University Graduate School of Medicine
| | - Tetsuo Shoji
- Department of Vascular Medicine, Osaka Metropolitan University Graduate school of Medicine
| | - Koutaro Yokote
- Department of Endocrinology, Hematology and Gerontology, Chiba University Graduate School of Medicine
| | - Hiroshi Yoshida
- Department of Laboratory Medicine, The Jikei University Kashiwa Hospital
| | | | - Juno Deguchi
- Department of Vascular Surgery, Saitama Medical Center, Saitama Medical University
| | - Kazushige Dobashi
- Department of Pediatrics, School of Medicine, University of Yamanashi
| | | | | | - Masumi Hara
- Department of Internal Medicine, Mizonokuchi Hospital, Teikyo University School of Medicine
| | - Mariko Harada-Shiba
- Cardiovascular Center, Osaka Medical and Pharmaceutical University
- Department of Molecular Pathogenesis, National Cerebral and Cardiovascular Center Research Institute
| | - Takumi Hirata
- Institute for Clinical and Translational Science, Nara Medical University
| | - Mami Iida
- Department of Internal Medicine and Cardiology, Gifu Prefectural General Medical Center
| | - Yoshiyuki Ikeda
- Department of Cardiovascular Medicine and Hypertension, Graduate School of Medical and Dental Sciences, Kagoshima University
| | - Shun Ishibashi
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Jichi Medical University, School of Medicine
- Current affiliation: Ishibashi Diabetes and Endocrine Clinic
| | - Hideyuki Kanda
- Department of Public Health, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University
| | - Shinji Kihara
- Medical Laboratory Science and Technology, Division of Health Sciences, Osaka University graduate School of medicine
| | - Kazuo Kitagawa
- Department of Neurology, Tokyo Women's Medical University Hospital
| | - Satoru Kodama
- Department of Prevention of Noncommunicable Diseases and Promotion of Health Checkup, Department of Hematology, Endocrinology and Metabolism, Niigata University Faculty of Medicine
| | - Masahiro Koseki
- Department of Cardiovascular Medicine, Osaka University Graduate School of Medicine
| | - Yoshiro Maezawa
- Department of Endocrinology, Hematology and Gerontology, Chiba University Graduate School of Medicine
| | - Daisaku Masuda
- Department of Cardiology, Center for Innovative Medicine and Therapeutics, Dementia Care Center, Doctor's Support Center, Health Care Center, Rinku General Medical Center
| | - Takashi Miida
- Department of Clinical Laboratory Medicine, Juntendo University Graduate School of Medicine
| | | | - Rimei Nishimura
- Department of Diabetes, Metabolism and Endocrinology, The Jikei University School of Medicine
| | - Koichi Node
- Department of Cardiovascular Medicine, Saga University
| | - Midori Noguchi
- Division of Public Health, Department of Social Medicine, Graduate School of Medicine, Osaka University
| | - Mitsuru Ohishi
- Department of Cardiovascular Medicine and Hypertension, Graduate School of Medical and Dental Sciences, Kagoshima University
| | - Isao Saito
- Department of Public Health and Epidemiology, Faculty of Medicine, Oita University
| | - Shojiro Sawada
- Division of Metabolism and Diabetes, Faculty of Medicine, Tohoku Medical and Pharmaceutical University
| | - Hirohito Sone
- Department of Hematology, Endocrinology and Metabolism, Niigata University Faculty of Medicine
| | - Minoru Takemoto
- Department of Diabetes, Metabolism and Endocrinology, International University of Health and Welfare
| | | | - Hidekatsu Yanai
- Department of Diabetes, Endocrinology and Metabolism, National Center for Global Health and Medicine Kohnodai Hospital
| |
Collapse
|
2
|
Claudio P, Gabriella M. Nephrotic syndrome: pathophysiology and consequences. J Nephrol 2023; 36:2179-2190. [PMID: 37466816 DOI: 10.1007/s40620-023-01697-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 05/30/2023] [Indexed: 07/20/2023]
Abstract
In patients with kidney disease, nephrotic syndrome can lead to several complications including progressive kidney dysfunction. Proteinuria may lead to the formation of cellular or fibrous crescents with reciprocal development of rapidly progressive glomerulonephritis or focal glomerulosclerosis. Proteinuria may also cause overload and dysfunction of tubular epithelial cells, eventually resulting in tubular atrophy and interstitial fibrosis. Hypoalbuminemia is usually associated with increased risk of mortality and kidney dysfunction. Dyslipidemia may increase the risk of atherosclerotic complications, cause podocyte dysfunction and contribute to vascular thrombosis. Urinary loss of anticoagulants and overproduction of coagulation factors may facilitate a hypercoagulable state. Edema, hypogammaglobulinemia, loss of complement factors, and immunosuppressive therapy can favor infection. Treatment of these complications may reduce their impact on the severity of NS. Nephrotic syndrome is a kidney disorder that can worsen the quality of life and increase the risk of kidney disease progression.
Collapse
Affiliation(s)
| | - Moroni Gabriella
- Department of Biomedical Sciences, Humanitas University, Via Rita Levi Montalcini 4, 20072, Pieve Emanuele, Milan, Italy
- Nephrology and Dialysis Division, IRCCS Humanitas Research Hospital, Via Manzoni 56, 20089, Rozzano, Milan, Italy
| |
Collapse
|
3
|
Komatsu T, Katsurada Y, Miyashita K, Abe S, Nishida T, Endo Y, Teramoto M, Sasaki K, Arakawa J, Sasaki M, Suzuki N, kuwata K, Imakiire T, Miyake T, Sakurada M, Matsukuma S, Hirano T, Uehara Y, Ikewaki K. Two Cases of Acquired High-Density Lipoprotein Deficiency with Immunoglobulin G4-Related Lecithin-Cholesterol Acyltransferase Autoantibody. J Atheroscler Thromb 2023; 30:1070-1082. [PMID: 36384970 PMCID: PMC10406652 DOI: 10.5551/jat.63616] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Accepted: 09/19/2022] [Indexed: 08/04/2023] Open
Abstract
Lecithin-cholesterol acyltransferase (LCAT) plays a significant role in the progression from premature to mature high-density lipoprotein (HDL) in circulation. Consequently, primary or secondary LCAT deletion or reduction naturally results in low serum HDL cholesterol levels. Recently, rare cases of acquired HDL deficiency with LCAT autoantibodies have been reported, mainly from Japan, where LCAT autoantibodies of immunoglobulin G (IgG) caused the HDL deficiency. Here to our knowledge, we report for the first time two cases of acquired HDL deficiency caused by IgG4 linked LCAT autoantibodies with or without a high serum IgG4 level. Furthermore, these cases can extend to a new concept of "IgG4 autoimmune disease" from the viewpoint of verifying the serum autoantibody and/or renal histopathology.
Collapse
Affiliation(s)
- Tomohiro Komatsu
- Division of Anti-aging and Vascular Medicine, Department of Internal Medicine, National Defense Medical College, Saitama, Japan
- Research Institute for Physical Activity, Fukuoka University, Fukuoka, Japan
- Center for Preventive, Anti-aging and Regenerative Medicine, Fukuoka University Hospital, Fukuoka, Japan
| | - Yuka Katsurada
- Department of Pathology and Laboratory Medicine, National Defense Medical College, Saitama, Japan
| | | | - Satomi Abe
- Research Institute for Physical Activity, Fukuoka University, Fukuoka, Japan
| | - Takafumi Nishida
- Division of Anti-aging and Vascular Medicine, Department of Internal Medicine, National Defense Medical College, Saitama, Japan
| | - Yasuhiro Endo
- Division of Anti-aging and Vascular Medicine, Department of Internal Medicine, National Defense Medical College, Saitama, Japan
| | - Manami Teramoto
- Division of Anti-aging and Vascular Medicine, Department of Internal Medicine, National Defense Medical College, Saitama, Japan
| | - Kei Sasaki
- Division of Anti-aging and Vascular Medicine, Department of Internal Medicine, National Defense Medical College, Saitama, Japan
- Center for Preventive, Anti-aging and Regenerative Medicine, Fukuoka University Hospital, Fukuoka, Japan
| | - Junko Arakawa
- Division of Anti-aging and Vascular Medicine, Department of Internal Medicine, National Defense Medical College, Saitama, Japan
| | - Makoto Sasaki
- Division of Anti-aging and Vascular Medicine, Department of Internal Medicine, National Defense Medical College, Saitama, Japan
| | - Natsuko Suzuki
- Diabetes Center, Ebina General Hospital, Kanagawa, Japan
| | - Koji kuwata
- Department of Nephrology and Endocrinology, Department of Internal Medicine, National Defense Medical College, Saitama, Japan
| | - Toshihiko Imakiire
- Department of Nephrology and Endocrinology, Department of Internal Medicine, National Defense Medical College, Saitama, Japan
| | | | | | - Susumu Matsukuma
- Department of Pathology and Laboratory Medicine, National Defense Medical College, Saitama, Japan
| | - Tsutomu Hirano
- Diabetes Center, Ebina General Hospital, Kanagawa, Japan
| | - Yoshinari Uehara
- Research Institute for Physical Activity, Fukuoka University, Fukuoka, Japan
- Center for Preventive, Anti-aging and Regenerative Medicine, Fukuoka University Hospital, Fukuoka, Japan
| | - Katsunori Ikewaki
- Division of Anti-aging and Vascular Medicine, Department of Internal Medicine, National Defense Medical College, Saitama, Japan
| |
Collapse
|
4
|
Aso M, Yamamoto TT, Kuroda M, Wada J, Kubota Y, Ishikawa K, Maezawa Y, Teramoto N, Tawada A, Asada S, Aoyagi Y, Kirinashizawa M, Onitake A, Matsuura Y, Yasunaga K, Konno SI, Nishino K, Yamamoto M, Miyoshi J, Kobayashi N, Tanio M, Ikeuchi T, Igari H, Mitsukawa N, Hanaoka H, Yokote K, Saito Y. First-in-human autologous implantation of genetically modified adipocytes expressing LCAT for the treatment of familial LCAT deficiency. Heliyon 2022; 8:e11271. [PMID: 36387451 PMCID: PMC9663876 DOI: 10.1016/j.heliyon.2022.e11271] [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: 10/14/2021] [Revised: 02/21/2022] [Accepted: 10/20/2022] [Indexed: 11/13/2022] Open
Abstract
Background Familial lecithin: cholesterol acyltransferase (LCAT) deficiency (FLD) is a severe inherited disease without effective treatment. Patients with FLD develop severe low HDL, corneal opacity, hemolytic anemia, and renal injury. Objective We developed genetically modified adipocytes (GMAC) secreting LCAT (LCAT-GMAC) for ex vivo gene therapy. GMACs were prepared from the patient’s adipocytes to express LCAT by retroviral gene transduction to secrete functional enzymes. This study aimed to evaluate the safety and efficacy of LCAT-GMAC implantation in an FLD patient. Methods Proliferative preadipocytes were obtained from a patient using a ceiling culture and retrovirally transduced with LCAT. After obtaining enough cells by expansion culture of the transduced cells, the resulting LCAT-GMACs were implanted into a patient with FLD. To evaluate the safety and efficacy, we analyzed the outcome of the autologous implantation for 24 weeks of observation and subsequent 240 weeks of the follow-up periods. Results This first-in-human autologous implantation of LCAT-GMACs was shown to be safe by evaluating adverse events. The LCAT-GMAC implantation increased serum LCAT activity by approximately 50% of the baseline and sustained over three years. Consistent with increased LCAT activity, intermediate-density lipoprotein (IDL) and free cholesterol levels of the small and very small HDL fractions decreased. We found the hemoglobin/haptoglobin complex in the hemolyzed pre-implantation sera of the patient. After one week of the implantation, the hemoglobin/haptoglobin complex almost disappeared. Immediately after the implantation, the patient's proteinuria decreased temporarily to mild levels and gradually increased to the baseline. At 48 weeks after implantation, the patient's proteinuria deteriorated with the development of mild hypertension. By the treatment with antihypertensives, the patient's blood pressure normalized. With the normalization of blood pressure, the proteinuria rapidly decreased to mild proteinuria levels. Conclusions LCAT-GMAC implantation in a patient with FLD is shown to be safe and appears to be effective, in part, for treating anemia and proteinuria in FLD.
Collapse
Affiliation(s)
| | | | - Masayuki Kuroda
- Center for Advanced Medicine, Chiba University Hospital, 2608677 Chiba, Japan
| | - Jun Wada
- Department of Nephrology, Rheumatology, Endocrinology and Metabolism, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 7008530 Okayama, Japan
| | - Yoshitaka Kubota
- Department of Plastic and Reconstructive Surgery, Chiba University, Faculty of Medicine, 2608670 Chiba, Japan
| | - Ko Ishikawa
- Department of Endocrinology, Hematology, and Gerontology, Chiba University, Graduates School of Medicine and Department of Diabetes, Metabolism, and Endocrinology, Chiba University Hospital, 2608670 Chiba, Japan
| | - Yoshiro Maezawa
- Department of Endocrinology, Hematology, and Gerontology, Chiba University, Graduates School of Medicine and Department of Diabetes, Metabolism, and Endocrinology, Chiba University Hospital, 2608670 Chiba, Japan
| | - Naoya Teramoto
- Department of Endocrinology, Hematology, and Gerontology, Chiba University, Graduates School of Medicine and Department of Diabetes, Metabolism, and Endocrinology, Chiba University Hospital, 2608670 Chiba, Japan
| | - Ayako Tawada
- Department of Ophthalmology and Visual Science, Chiba University Graduate School of Medicine, 2608670 Chiba, Japan
| | | | | | | | | | | | | | | | | | | | | | | | | | - Takayuki Ikeuchi
- Chiba University Hospital Clinical Research Center, 2608677 Chiba, Japan
| | - Hidetoshi Igari
- Division of Infection Control, Chiba University Hospital, 2608677 Chiba, Japan
| | - Nobuyuki Mitsukawa
- Department of Plastic and Reconstructive Surgery, Chiba University, Faculty of Medicine, 2608670 Chiba, Japan
| | - Hideki Hanaoka
- Chiba University Hospital Clinical Research Center, 2608677 Chiba, Japan
| | - Koutaro Yokote
- Department of Endocrinology, Hematology, and Gerontology, Chiba University, Graduates School of Medicine and Department of Diabetes, Metabolism, and Endocrinology, Chiba University Hospital, 2608670 Chiba, Japan
- Corresponding author.
| | | |
Collapse
|
5
|
LCAT- targeted therapies: Progress, failures and future. Biomed Pharmacother 2022; 147:112677. [PMID: 35121343 DOI: 10.1016/j.biopha.2022.112677] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 01/21/2022] [Accepted: 01/26/2022] [Indexed: 11/22/2022] Open
Abstract
Lecithin: cholesterol acyltransferase (LCAT) is the only enzyme in plasma which is able to esterify cholesterol and boost cholesterol esterify with phospholipid-derived acyl chains. In order to better understand the progress of LCAT research, it is always inescapable that it is linked to high-density lipoprotein (HDL) metabolism and reverse cholesterol transport (RCT). Because LCAT plays a central role in HDL metabolism and RCT, many animal studies and clinical studies are currently aimed at improving plasma lipid metabolism by increasing LCAT activity in order to find better treatment options for familial LCAT deficiency (FLD), fish eye disease (FED), and cardiovascular disease. Recombinant human LCAT (rhLCAT) injections, cells and gene therapy, and small molecule activators have been carried out with promising results. Recently rhLCAT therapies have entered clinical phase II trials with good prospects. In this review, we discuss the diseases associated with LCAT and therapies that use LCAT as a target hoping to find out whether LCAT can be an effective therapeutic target for coronary heart disease and atherosclerosis. Also, probing the mechanism of action of LCAT may help better understand the heterogeneity of HDL and the action mechanism of dynamic lipoprotein particles.
Collapse
|
6
|
Kuroda M, Bujo H, Yokote K, Murano T, Yamaguchi T, Ogura M, Ikewaki K, Koseki M, Takeuchi Y, Nakatsuka A, Hori M, Matsuki K, Miida T, Yokoyama S, Wada J, Harada-Shiba M. Current Status of Familial LCAT Deficiency in Japan. J Atheroscler Thromb 2021; 28:679-691. [PMID: 33867422 PMCID: PMC8265425 DOI: 10.5551/jat.rv17051] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Lecithin cholesterol acyltransferase (LCAT) is a lipid-modification enzyme that catalyzes the transfer of the acyl chain from the second position of lecithin to the hydroxyl group of cholesterol (FC) on plasma lipoproteins to form cholesteryl acylester and lysolecithin. Familial LCAT deficiency is an intractable autosomal recessive disorder caused by inherited dysfunction of the LCAT enzyme. The disease appears in two different phenotypes depending on the position of the gene mutation: familial LCAT deficiency (FLD, OMIM 245900) that lacks esterification activity on both HDL and ApoB-containing lipoproteins, and fish-eye disease (FED, OMIM 136120) that lacks activity only on HDL. Impaired metabolism of cholesterol and phospholipids due to LCAT dysfunction results in abnormal concentrations, composition and morphology of plasma lipoproteins and further causes ectopic lipid accumulation and/or abnormal lipid composition in certain tissues/cells, and serious dysfunction and complications in certain organs. Marked reduction of plasma HDL-cholesterol (HDL-C) and corneal opacity are common clinical manifestations of FLD and FED. FLD is also accompanied by anemia, proteinuria and progressive renal failure that eventually requires hemodialysis. Replacement therapy with the LCAT enzyme should prevent progression of serious complications, particularly renal dysfunction and corneal opacity. A clinical research project aiming at gene/cell therapy is currently underway.
Collapse
Affiliation(s)
- Masayuki Kuroda
- Center for Advanced Medicine, Chiba University Hospital, Chiba University
| | - Hideaki Bujo
- Department of Clinical-Laboratory and Experimental-Research Medicine, Toho University Sakura Medical Center
| | - Koutaro Yokote
- Department of Endocrinology, Hematology and Gerontology, Chiba University Graduate School of Medicine
| | - Takeyoshi Murano
- Clinical Laboratory Program, Faculty of Science, Toho University
| | - Takashi Yamaguchi
- Center of Diabetes, Endocrinology and Metabolism, Toho University Sakura Medical Center
| | - Masatsune Ogura
- Department of Molecular Innovation in Lipidology, National Cerebral and Cardiovascular Center Research Institute
| | - Katsunori Ikewaki
- Division of Neurology, Anti-Aging, and Vascular Medicine, Department of Internal Medicine, National Defense Medical College
| | - Masahiro Koseki
- Division of Cardiovascular Medicine, Department of Medicine, Osaka University Graduate School of Medicine
| | - Yasuo Takeuchi
- Division of Nephrology, Kitasato University School of Medicine
| | - Atsuko Nakatsuka
- Department of Nephrology, Rheumatology, Endocrinology and Metabolism, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences
| | - Mika Hori
- Department of Endocrinology, Research Institute of Environmental Medicine, Nagoya University
| | - Kota Matsuki
- Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine
| | - Takashi Miida
- Department of Clinical Laboratory Medicine, Juntendo University Graduate School of Medicine
| | | | - Jun Wada
- Department of Nephrology, Rheumatology, Endocrinology and Metabolism, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences
| | - Mariko Harada-Shiba
- Department of Molecular Pathogenesis, National Cerebral and Cardiovascular Center Research Institute
| |
Collapse
|
7
|
Ronco P, Debiec H. Molecular Pathogenesis of Membranous Nephropathy. ANNUAL REVIEW OF PATHOLOGY-MECHANISMS OF DISEASE 2019; 15:287-313. [PMID: 31622560 DOI: 10.1146/annurev-pathol-020117-043811] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Membranous nephropathy is a noninflammatory autoimmune disease of the kidney glomerulus, characterized by the formation of immune deposits, complement-mediated proteinuria, and risk of renal failure. Considerable advances in understanding the molecular pathogenesis have occurred with the identification of several antigens [neutral endopeptidase, phospholipase A2 receptor (PLA2R), thrombospondin domain-containing 7A (THSD7A)] in cases arising from the neonatal period to adulthood and the characterization of antibody-binding domains (that is, epitopes). Immunization against PLA2R occurs in 70% to 80% of adult cases. The development of highly specific and sensitive assays of circulating antibodies has induced a paradigm shift in diagnosis and treatment monitoring. In addition, several interacting loci in HLA-DQ, HLA-DR, and PLA2R1, as well as classical human leukocyte antigen (HLA)-D alleles have been identified as being risk factors, depending on a patient's ethnicity. Additionally, mechanisms of antibody pathogenicity and pathways of complement activation are now better understood. Further research is mandatory for designing new therapeutic strategies, including the identifying triggering events, the molecular bases of remission and progression, and the T cell epitopes involved.
Collapse
Affiliation(s)
- Pierre Ronco
- Rare and Common Kidney Diseases: From Molecular Mechanisms to Personalized Medicine Unit, INSERM UMRS 1155, Sorbonne Université, 75020 Paris, France;
| | - Hanna Debiec
- Rare and Common Kidney Diseases: From Molecular Mechanisms to Personalized Medicine Unit, INSERM UMRS 1155, Sorbonne Université, 75020 Paris, France;
| |
Collapse
|
8
|
Abstract
PURPOSE OF REVIEW Lipoprotein-X (Lp-X) is an abnormal lipoprotein containing abundant free cholesterol and phospholipids, as well as some apolipoprotein E (apoE). Serum Lp-X increases in patients with cholestasis and lecithin-cholesterol acyltransferase deficiency, as well as in those receiving intravenous lipid emulsion. Lp-X is often associated with skin xanthomas in cholestatic patients. However, earlier studies showed that Lp-X is not taken up by murine macrophages, but exerts antiatherogenic actions. In this review, we discuss the heterogeneity of Lp-X and its potential atherogenicity. RECENT FINDINGS Mass spectrometry revealed that Lp-X of cholestatic patients is similar in lipid composition to low-density lipoprotein (LDL) and high-density lipoprotein, but not to bile acids, suggesting that Lp-X is synthesized in the liver. Palmar xanthomas appear in patients with cholestasis, but regress over months after improvement of hypercholesterolemia. Lp-X isolated from cholestatic patients is rich in apoE, and causes more lipid accumulation than oxidized LDL and acetyl LDL in human monocyte-derived macrophages. SUMMARY Lp-X is heterogeneous in apoE content. Lp-X is taken up in cholestatic patients by apoE-recognizing lipoprotein receptors. Further research is warranted to fully understand the atherogenicity of Lp-X and the clinical significance of elevated Lp-X concentrations, particularly in cholestatic patients.
Collapse
Affiliation(s)
- Takashi Miida
- Department of Clinical Laboratory Medicine, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | | |
Collapse
|