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De Leo E, Taranta A, Raso R, Pezzullo M, Piccione M, Matteo V, Vitale A, Bellomo F, Goffredo BM, Diomedi Camassei F, Prencipe G, Rega LR, Emma F. Long-term effects of luteolin in a mouse model of nephropathic cystinosis. Biomed Pharmacother 2024; 178:117236. [PMID: 39096619 DOI: 10.1016/j.biopha.2024.117236] [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: 06/04/2024] [Revised: 07/24/2024] [Accepted: 07/30/2024] [Indexed: 08/05/2024] Open
Abstract
In infantile nephropathic cystinosis, variants of the CTNS gene cause accumulation of cystine in lysosomes, causing progressive damage to most organs. Patients usually present before 1 year of age with signs of renal Fanconi syndrome. Cysteamine therapy allows cystine clearance from lysosomes and delays kidney damage but does not prevent progression to end-stage kidney disease, suggesting that pathways unrelated to cystine accumulation are also involved. Among these, impaired autophagy, altered endolysosomal trafficking, and increased apoptosis have emerged in recent years as potential targets for new therapies. We previously showed that luteolin, a flavonoid compound, improves these abnormal pathways in cystinotic cells and in zebrafish models of the disease. Herein, we have investigated if prolonged luteolin treatment ameliorates kidney damage in a murine model of cystinosis. To this end, we have treated Ctns-/- mice from 2 to 8 months with 150 mg/kg/day of luteolin. No significant side effects were observed. Compared to untreated animals, analyses of kidney cortex samples obtained after sacrifice showed that luteolin decreased p62/SQSTM1 levels (p <0.001), improved the number, size, and distribution of LAMP1-positive structures (p <0.02), and decreased tissue expression of cleaved caspase 3 (p <0.001). However, we did not observe improvements in renal Fanconi syndrome and kidney inflammation. Kidney function remained normal during the time of the study. These results indicate that luteolin has positive effects on the apoptosis and endo-lysosomal defects of cystinotic proximal tubular cells. However, these beneficial effects did not translate into improvement of renal Fanconi syndrome.
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Affiliation(s)
- Ester De Leo
- Laboratory of Nephrology, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy.
| | - Anna Taranta
- Laboratory of Nephrology, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Roberto Raso
- Laboratory of Nephrology, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Marco Pezzullo
- Core Facilities, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Michela Piccione
- Confocal Microscopy Core Facility, Research Laboratories, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Valentina Matteo
- Laboratory of Immuno-Rheumatology, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Alessia Vitale
- Laboratory of Metabolic Diseases, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Francesco Bellomo
- Laboratory of Nephrology, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Bianca Maria Goffredo
- Laboratory of Metabolic Diseases, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | | | - Giusi Prencipe
- Laboratory of Immuno-Rheumatology, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Laura Rita Rega
- Laboratory of Nephrology, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Francesco Emma
- Division of Nephrology, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
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Cheung WW, Zhou P, Zheng R, Gertler A, Oliveira EA, Mak RH. Leptin signalling altered in infantile nephropathic cystinosis-related bone disorder. J Cachexia Sarcopenia Muscle 2024. [PMID: 39210624 DOI: 10.1002/jcsm.13579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Revised: 07/01/2024] [Accepted: 07/31/2024] [Indexed: 09/04/2024] Open
Abstract
BACKGROUND The CTNS gene mutation causes infantile nephropathic cystinosis (INC). Patients with INC develop Fanconi syndrome and chronic kidney disease (CKD) with significant bone deformations. C57BL/6 Ctns-/- mice are an animal model for studying INC. Hyperleptinaemia results from the kidney's inability to eliminate the hormone leptin in CKD. Ctns-/- mice have elevated serum leptin concentrations. Leptin regulates bone metabolism through its receptor that signals further via the hypothalamic melanocortin 4 receptor (MC4R). Leptin signalling may affect bone health in Ctns-/- mice. METHODS We first defined the time course of bone abnormalities in Ctns-/- mice between 1 and 12 months of age. We used both genetic and pharmacological approaches to investigate leptin signalling in Ctns-/- mice. We generated Ctns-/-Mc4r-/- double knockout mice. Bone phenotype of Ctns-/-Mc4r-/- mice, Ctns-/- mice and wild type (WT) mice at 1, 4, and 9 months of age were compared. We then treated 12-month-old Ctns-/- mice and WT mice with a pegylated leptin receptor antagonist (PLA) (7 mg/kg/day, IP), a MC4R antagonist agouti-related peptide (AgRP) (2 nmol, intracranial infusion on days 0, 3, 6, 9, 12, 15, 18, 21, 24, and 27), or vehicle (normal saline), respectively, for 28 days. Whole-body (BMC/BMD, bone area) and femoral bone phenotype (BMC/BMD, bone area, length and failure load) of mice were measured by DXA and femoral shaft biochemical test. We also measured lean mass content by EchoMRI and muscle function (grip strength and rotarod activity) in mice. Femur protein content of JAK2 and STAT3 was measured by ELISA kits, respectively. RESULTS Bone defects are present in Ctns-/- mice throughout its first year of life. The deletion of the Mc4r gene attenuated bone disorder in Ctns-/- mice. Femoral BMD, bone area, length, and strength (failure load) were significantly increased in 9-month-old Ctns-/-Mc4r-/- mice than in age-matched Ctns-/- mice. PLA and AgRP treatment significantly increased femoral bone density (BMC/BMD) and mechanical strength in 12-month-old Ctns-/- mice. We adopted the pair-feeding approach for this study to show that the protective effects of PLA or AgRP on bone phenotype are independent of their potent orexigenic effect. Furthermore, an increase in lean mass and in vivo muscle function (grip strength and rotarod activity) are associated with improvements in bone phenotype (femoral BMC/BMD and mechanical strength) in Ctns-/- mice, suggesting a muscle-bone interplay. Decreased femur protein content of JAK2 and STAT3 was evident in Ctns-/- mice. PLA or AgRP treatment attenuated femur STAT3 content in Ctns-/- mice. CONCLUSIONS Our findings suggest a significant role for dysregulated leptin signalling in INC-related bone disorder, either directly or potentially involving a muscle-bone interplay. Leptin signalling blockade may represent a novel approach to treating bone disease as well as muscle wasting in INC.
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Affiliation(s)
- Wai W Cheung
- Division of Pediatric Nephrology, Rady Children's Hospital, University of California, San Diego, La Jolla, CA, USA
| | - Ping Zhou
- Department of Pediatric Nephrology and Rheumatology, Sichuan Provincial Maternity and Child Health Care Hospital, Sichuan Clinical Research Center for Pediatric Nephrology and The Affiliated Women's and Children's Hospital of Chengdu Medical College, Chengdu, China
| | - Ronghao Zheng
- Department of Pediatric Nephrology, Rheumatology, and Immunology, Maternal and Child Health Hospital of Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Arieh Gertler
- School of Biological and Population Health Sciences, Institute of Biochemistry, Food Science and Nutrition, Hebrew University of Jerusalem, Rehovot, Israel
| | - Eduardo A Oliveira
- Department of Pediatrics, Division of Pediatric Nephrology, Faculty of Medicine, Federal University of Minas Gerais (UFMG), Belo Horizonte, Brazil
| | - Robert H Mak
- Division of Pediatric Nephrology, Rady Children's Hospital, University of California, San Diego, La Jolla, CA, USA
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Rossi MN, Matteo V, Diomedi-Camassei F, De Leo E, Devuyst O, Lamkanfi M, Caiello I, Loricchio E, Bellomo F, Taranta A, Emma F, De Benedetti F, Prencipe G. Nlrp2 deletion ameliorates kidney damage in a mouse model of cystinosis. Front Immunol 2024; 15:1373224. [PMID: 38633264 PMCID: PMC11021658 DOI: 10.3389/fimmu.2024.1373224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Accepted: 03/18/2024] [Indexed: 04/19/2024] Open
Abstract
Cystinosis is a rare autosomal recessive disorder caused by mutations in the CTNS gene that encodes cystinosin, a ubiquitous lysosomal cystine/H+ antiporter. The hallmark of the disease is progressive accumulation of cystine and cystine crystals in virtually all tissues. At the kidney level, human cystinosis is characterized by the development of renal Fanconi syndrome and progressive glomerular and interstitial damage leading to end-stage kidney disease in the second or third decade of life. The exact molecular mechanisms involved in the pathogenesis of renal disease in cystinosis are incompletely elucidated. We have previously shown upregulation of NLRP2 in human cystinotic proximal tubular epithelial cells and its role in promoting inflammatory and profibrotic responses. Herein, we have investigated the role of NLRP2 in vivo using a mouse model of cystinosis in which we have confirmed upregulation of Nlrp2 in the renal parenchyma. Our studies show that double knock out Ctns-/- Nlrp2-/- animals exhibit delayed development of Fanconi syndrome and kidney tissue damage. Specifically, we observed at 4-6 months of age that animals had less glucosuria and calciuria and markedly preserved renal tissue, as assessed by significantly lower levels of inflammatory cell infiltration, tubular atrophy, and interstitial fibrosis. Also, the mRNA expression of some inflammatory mediators (Cxcl1 and Saa1) and the rate of apoptosis were significantly decreased in 4-6-month old kidneys harvested from Ctns-/- Nlrp2-/- mice compared to those obtained from Ctns-/-mice. At 12-14 months of age, renal histological was markedly altered in both genetic models, although double KO animals had lower degree of polyuria and low molecular weight proteinuria and decreased mRNA expression levels of Il6 and Mcp1. Altogether, these data indicate that Nlrp2 is a potential pharmacological target for delaying progression of kidney disease in cystinosis.
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Affiliation(s)
- Marianna Nicoletta Rossi
- Laboratory of Immuno-Rheumatology, Bambino Gesù Children’s Hospital, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Roma, Italy
- Department of Science, University of Rome “Roma Tre”, Rome, Italy
| | - Valentina Matteo
- Laboratory of Immuno-Rheumatology, Bambino Gesù Children’s Hospital, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Roma, Italy
| | - Francesca Diomedi-Camassei
- Department of Laboratories, Pathology Unit, Bambino Gesù Children’s Hospital, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Roma, Italy
| | - Ester De Leo
- Division of Nephrology, Bambino Gesù Children’s Hospital, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Roma, Italy
| | - Olivier Devuyst
- Mechanisms of Inherited Kidney Disorders Group, Institute of Physiology, University of Zurich, Zurich, Switzerland
| | - Mohamed Lamkanfi
- Laboratory of Medical Immunology, Department of Internal Medicine and Paediatrics, Ghent University, Ghent, Belgium
| | - Ivan Caiello
- Laboratory of Immuno-Rheumatology, Bambino Gesù Children’s Hospital, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Roma, Italy
| | - Elena Loricchio
- Laboratory of Immuno-Rheumatology, Bambino Gesù Children’s Hospital, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Roma, Italy
| | - Francesco Bellomo
- Division of Nephrology, Bambino Gesù Children’s Hospital, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Roma, Italy
| | - Anna Taranta
- Division of Nephrology, Bambino Gesù Children’s Hospital, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Roma, Italy
| | - Francesco Emma
- Division of Nephrology, Bambino Gesù Children’s Hospital, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Roma, Italy
| | - Fabrizio De Benedetti
- Laboratory of Immuno-Rheumatology, Bambino Gesù Children’s Hospital, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Roma, Italy
| | - Giusi Prencipe
- Laboratory of Immuno-Rheumatology, Bambino Gesù Children’s Hospital, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Roma, Italy
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Zhu Y, Liu W, Qi Z. Adipose tissue browning and thermogenesis under physiologically energetic challenges: a remodelled thermogenic system. J Physiol 2024; 602:23-48. [PMID: 38019069 DOI: 10.1113/jp285269] [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: 08/09/2023] [Accepted: 11/16/2023] [Indexed: 11/30/2023] Open
Abstract
Metabolic diseases such as obesity and diabetes are often thought to be caused by reduced energy expenditure, which poses a serious threat to human health. Cold exposure, exercise and caloric restriction have been shown to promote adipose tissue browning and thermogenesis. These physiological interventions increase energy expenditure and thus have emerged as promising strategies for mitigating metabolic disorders. However, that increased adipose tissue browning and thermogenesis elevate thermogenic consumption is not a reasonable explanation when humans and animals confront energetic challenges imposed by these interventions. In this review, we collected numerous results on adipose tissue browning and whitening and evaluated this bi-directional conversion of adipocytes from the perspective of energy homeostasis. Here, we propose a new interpretation of the role of adipose tissue browning under energetic challenges: increased adipose tissue browning and thermogenesis under energy challenge is not to enhance energy expenditure, but to reestablish a more economical thermogenic pattern to maintain the core body temperature. This can be achieved by enhancing the contribution of non-shivering thermogenesis (adipose tissue browning and thermogenesis) and lowering shivering thermogenesis and high intensity shivering. Consequently, the proportion of heat production in fat increases and that in skeletal muscle decreases, enabling skeletal muscle to devote more energy reserves to overcoming environmental stress.
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Affiliation(s)
- Yupeng Zhu
- The Key Laboratory of Adolescent Health Assessment and Exercise Intervention (Ministry of Education), East China Normal University, Shanghai, China
- School of Physical Education and Health, East China Normal University, Shanghai, China
- Sino-French Joint Research Center of Sport Science, East China Normal University, Shanghai, China
| | - Weina Liu
- The Key Laboratory of Adolescent Health Assessment and Exercise Intervention (Ministry of Education), East China Normal University, Shanghai, China
- School of Physical Education and Health, East China Normal University, Shanghai, China
| | - Zhengtang Qi
- The Key Laboratory of Adolescent Health Assessment and Exercise Intervention (Ministry of Education), East China Normal University, Shanghai, China
- School of Physical Education and Health, East China Normal University, Shanghai, China
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Serrano E, Shenoy P, Martinez Cantarin MP. Adipose tissue metabolic changes in chronic kidney disease. IMMUNOMETABOLISM (COBHAM (SURREY, ENGLAND)) 2023; 5:e00023. [PMID: 37128293 PMCID: PMC10144329 DOI: 10.1097/in9.0000000000000023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Accepted: 04/04/2023] [Indexed: 05/03/2023]
Abstract
Adipose tissue is a complex organ whose functions go beyond being an energy reservoir to sustain proper body energy homeostasis. Functioning as an endocrine organ, the adipose tissue has an active role in the body's metabolic balance regulation through several secreted factors generally termed as adipokines. Thus, adipose tissue dysregulation in chronic kidney disease (CKD) can have a deep impact in the pathophysiology of diseases associated with metabolic dysregulation including metabolic syndrome, insulin resistance (IR), atherosclerosis, and even cachexia. CKD is a progressive disorder linked to increased morbidity and mortality. Despite being characterized by renal function loss, CKD is accompanied by metabolic disturbances such as dyslipidemia, protein energy wasting, chronic low-grade inflammation, IR, and lipid redistribution. Thus far, the mechanisms by which these changes occur and the role of adipose tissue in CKD development and progression are unclear. Further understanding of how these factors develop could have implications for the management of CKD by helping identify pharmacological targets to improve CKD outcomes.
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Affiliation(s)
- Eurico Serrano
- Division of Nephrology, Department of Medicine, Sidney Kimmel Medical College at Thomas Jefferson University, Philadelphia, PA, USA
| | - Prashamsa Shenoy
- Division of Nephrology, Department of Medicine, Sidney Kimmel Medical College at Thomas Jefferson University, Philadelphia, PA, USA
| | - Maria Paula Martinez Cantarin
- Division of Nephrology, Department of Medicine, Sidney Kimmel Medical College at Thomas Jefferson University, Philadelphia, PA, USA
- *Correspondence: Maria Paula Martinez Cantarin, E-mail:
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De Leo E, Taranta A, Raso R, Polishchuk E, D'Oria V, Pezzullo M, Goffredo BM, Cairoli S, Bellomo F, Battafarano G, Camassei FD, Del Fattore A, Polishchuk R, Emma F, Rega LR. Genistein improves renal disease in a mouse model of nephropathic cystinosis: a comparison study with cysteamine. Hum Mol Genet 2023; 32:1090-1101. [PMID: 36300303 PMCID: PMC10026248 DOI: 10.1093/hmg/ddac266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 09/26/2022] [Accepted: 10/21/2022] [Indexed: 11/12/2022] Open
Abstract
Cysteamine is currently the only therapy for nephropathic cystinosis. It significantly improves life expectancy and delays progression to end-stage kidney disease; however, it cannot prevent it. Unfortunately, compliance to therapy is often weak, particularly during adolescence. Therefore, finding better treatments is a priority in the field of cystinosis. Previously, we found that genistein, an isoflavone particularly enriched in soy, can revert part of the cystinotic cellular phenotype that is not sensitive to cysteamine in vitro. To test the effects of genistein in vivo, we fed 2-month-old wild-type and Ctns-/- female mice with either a control diet, a genistein-containing diet or a cysteamine-containing diet for 14 months. Genistein (160 mg/kg/day) did not affect the growth of the mice or hepatic functionality. Compared with untreated mice at 16 months, Ctns-/- mice fed with genistein had lower cystine concentrations in their kidneys, reduced formation of cystine crystals, a smaller number of LAMP1-positive structures and an overall better-preserved parenchymal architecture. Cysteamine (400 mg/kg/day) was efficient in reverting the lysosomal phenotype and in preventing the development of renal lesions. These preclinical data indicate that genistein ameliorates kidney injury resulting from cystinosis with no side effects. Genistein therapy represents a potential treatment to improve the outcome for patients with cystinosis.
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Affiliation(s)
- Ester De Leo
- Renal Diseases Research Unit, Genetics and Rare Diseases Research Area, Bambino Gesù Children's Hospital, IRCCS, 00146 Rome, Italy
| | - Anna Taranta
- Renal Diseases Research Unit, Genetics and Rare Diseases Research Area, Bambino Gesù Children's Hospital, IRCCS, 00146 Rome, Italy
| | - Roberto Raso
- Renal Diseases Research Unit, Genetics and Rare Diseases Research Area, Bambino Gesù Children's Hospital, IRCCS, 00146 Rome, Italy
| | - Elena Polishchuk
- Telethon Institute of Genetics and Medicine, 80078 Pozzuoli, Italy
| | - Valentina D'Oria
- Research Laboratories, Confocal Microscopy Core Facility, Bambino Gesù Children's Hospital, IRCCS, 00146 Rome, Italy
| | - Marco Pezzullo
- Core Facilities, Bambino Gesù Children's Hospital, IRCCS, 00146 Rome, Italy
| | - Bianca Maria Goffredo
- Department of Pediatric Specialties and Liver-Kidney Transplantation, Division of Metabolic Biochemistry and Drug Biology, Bambino Gesù Children's Hospital, IRCCS, 00146 Rome, Italy
| | - Sara Cairoli
- Department of Pediatric Specialties and Liver-Kidney Transplantation, Division of Metabolic Biochemistry and Drug Biology, Bambino Gesù Children's Hospital, IRCCS, 00146 Rome, Italy
| | - Francesco Bellomo
- Renal Diseases Research Unit, Genetics and Rare Diseases Research Area, Bambino Gesù Children's Hospital, IRCCS, 00146 Rome, Italy
| | - Giulia Battafarano
- Bone Physiopathology Research Unit, Genetics and Rare Diseases Research Division, Bambino Gesù Children's Hospital, IRCCS, 00146 Rome, Italy
| | | | - Andrea Del Fattore
- Bone Physiopathology Research Unit, Genetics and Rare Diseases Research Division, Bambino Gesù Children's Hospital, IRCCS, 00146 Rome, Italy
| | - Roman Polishchuk
- Telethon Institute of Genetics and Medicine, 80078 Pozzuoli, Italy
| | - Francesco Emma
- Renal Diseases Research Unit, Genetics and Rare Diseases Research Area, Bambino Gesù Children's Hospital, IRCCS, 00146 Rome, Italy
- Division of Nephrology, Department of Pediatric Subspecialties, Bambino Gesù Children's Hospital, IRCCS, 00146 Rome, Italy
| | - Laura Rita Rega
- Renal Diseases Research Unit, Genetics and Rare Diseases Research Area, Bambino Gesù Children's Hospital, IRCCS, 00146 Rome, Italy
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Metabolic Advantage of 25(OH)D3 versus 1,25(OH)2D3 Supplementation in Infantile Nephropathic Cystinosis-Associated Adipose Tissue Browning and Muscle Wasting. Cells 2022; 11:cells11203264. [PMID: 36291130 PMCID: PMC9600749 DOI: 10.3390/cells11203264] [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: 05/16/2022] [Revised: 09/13/2022] [Accepted: 10/14/2022] [Indexed: 12/03/2022] Open
Abstract
Manifestations of infantile nephropathic cystinosis (INC) often include cachexia and deficiency of circulating vitamin D metabolites. We examined the impact of 25(OH)D3 versus 1,25(OH)2D3 repletion in Ctns null mice, a mouse model of INC. Six weeks of intraperitoneal administration of 25(OH)D3 (75 μg/kg/day) or 1,25(OH)2D3 (60 ng/kg/day) resulted in Ctns−/− mice corrected low circulating 25(OH)D3 or 1,25(OH)2D3 concentrations. While 25(OH)D3 administration in Ctns−/− mice normalized several metabolic parameters characteristic of cachexia as well as muscle function in vivo, 1,25(OH)2D3 did not. Administration of 25(OH)D3 in Ctns−/− mice increased muscle fiber size and decreased fat infiltration of skeletal muscle, which was accompanied by a reduction of abnormal muscle signaling pathways. 1,25(OH)2D3 administration was not as effective. In conclusion, 25(OH)D3 supplementation exerts metabolic advantages over 1,25(OH)2D3 supplementation by amelioration of muscle atrophy and fat browning in Ctns−/− mice.
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Kluck R, Müller S, Jagodzinski C, Hohenfellner K, Büscher A, Kemper MJ, Oh J, Billing H, Thumfart J, Weber LT, Acham-Roschitz B, Arbeiter K, Tönshoff B, Hagenberg M, Kanzelmeyer N, Pavičić L, Haffner D, Zivicnjak M. Body growth, upper arm fat area, and clinical parameters in children with nephropathic cystinosis compared with other pediatric chronic kidney disease entities. J Inherit Metab Dis 2022; 45:192-202. [PMID: 34989402 DOI: 10.1002/jimd.12473] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2021] [Revised: 12/30/2021] [Accepted: 01/04/2022] [Indexed: 11/12/2022]
Abstract
Children with infantile nephropathic cystinosis (INC), an inherited lysosomal storage disease resulting in cystine accumulation in all body cells, are prone to progressive chronic kidney disease (CKD), impaired growth and reduced weight gain; however, systematic anthropometric analyses are lacking. In this prospective multicenter study we investigated linear growth, body proportion, body mass index (BMI), upper arm fat area (UFA) and biochemical parameters in 43 pediatric INC patients with CKD stages 1 to 5 and 49 age-matched CKD controls, with 193 annual measurements. INC patients showed more impaired height than CKD controls (-1.8 vs -0.7 z-score; P < .001), despite adequate cysteamine therapy, treatment for Fanconi syndrome and more frequent use of growth hormone. Only the youngest INC patients shared the same body pattern with CKD controls characterized by preferential impairment of leg length and rather preserved trunk length. In late-prepuberty, body pattern changed only in INC patients due to improved leg growth and more impaired trunk length. Mean UFA z-score in INC patients was slightly reduced in early childhood and progressively decreased thereafter reaching -0.8 z-score in adolescence, while CKD controls showed a steady increase in standardized BMI and UFA especially during adolescent age. Menarche in female INC patients was significantly delayed compared to CKD controls. Our data indicate that with age and progression of disease, pediatric INC patients undergo unique changes of body growth and fat stores that are distinct from those with CKD stemming from other causes, suggesting other factors apart from CKD to contribute to this development. Pediatric patients with infantile nephropathic cystinosis display more severe impaired linear growth than other peer CKD patients, despite of cysteamine treatment, supplementation for Fanconi syndrome, and more frequent use of growth hormone, with a distinct change of body proportions and overall lower body fat.
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Affiliation(s)
- Rika Kluck
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School, Children's Hospital, Hannover, Germany
| | - Sophia Müller
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School, Children's Hospital, Hannover, Germany
| | - Celina Jagodzinski
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School, Children's Hospital, Hannover, Germany
| | | | - Anja Büscher
- Department of Pediatrics II, University Hospital Essen, Essen, Germany
| | - Markus J Kemper
- Asklepios Medical School, Asklepios Hospital North-Heidberg, Hamburg, Germany
| | - Jun Oh
- Division of Pediatric Nephrology, University Children's Hospital Hamburg, Hamburg, Germany
| | - Heiko Billing
- Clinic for Pediatric and Adolescent Medicine, RHK Clinic Ludwigsburg, Ludwigsburg, Germany
| | - Julia Thumfart
- Department of Pediatric Gastroenterology, Nephrology and Metabolic Diseases, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Lutz T Weber
- Division of Pediatric Nephrology, Children's and Adolescents' Hospital, University of Cologne, Faculty of Medicine and University Hospital, Cologne, Germany
| | | | - Klaus Arbeiter
- Division of Pediatric Nephrology and Gastroenterology, Medical University, Vienna, Austria
| | - Burkhard Tönshoff
- Department of Pediatrics I, University Children's Hospital Heidelberg, Heidelberg, Germany
| | - Martina Hagenberg
- Department of Pediatrics, Hospital St. Elisabeth and St. Barbara, Halle (Saale), Germany
| | - Nele Kanzelmeyer
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School, Children's Hospital, Hannover, Germany
| | | | - Dieter Haffner
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School, Children's Hospital, Hannover, Germany
| | - Miroslav Zivicnjak
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School, Children's Hospital, Hannover, Germany
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Muscle and Bone Impairment in Infantile Nephropathic Cystinosis: New Concepts. Cells 2022; 11:cells11010170. [PMID: 35011732 PMCID: PMC8749987 DOI: 10.3390/cells11010170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 12/28/2021] [Accepted: 01/01/2022] [Indexed: 11/17/2022] Open
Abstract
Cystinosis Metabolic Bone Disease (CMBD) has emerged during the last decade as a well-recognized, long-term complication in patients suffering from infantile nephropathic cystinosis (INC), resulting in significant morbidity and impaired quality of life in teenagers and adults with INC. Its underlying pathophysiology is complex and multifactorial, associating complementary, albeit distinct entities, in addition to ordinary mineral and bone disorders observed in other types of chronic kidney disease. Amongst these long-term consequences are renal Fanconi syndrome, hypophosphatemic rickets, malnutrition, hormonal abnormalities, muscular impairment, and intrinsic cellular bone defects in bone cells, due to CTNS mutations. Recent research data in the field have demonstrated abnormal mineral regulation, intrinsic bone defects, cysteamine toxicity, muscle wasting and, likely interleukin-1-driven inflammation in the setting of CMBD. Here we summarize these new pathophysiological deregulations and discuss the crucial interplay between bone and muscle in INC. In future, vitamin D and/or biotherapies targeting the IL1β pathway may improve muscle wasting and subsequently CMBD, but this remains to be proven.
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Cheung PY, Harrison PT, Davidson AJ, Hollywood JA. In Vitro and In Vivo Models to Study Nephropathic Cystinosis. Cells 2021; 11:6. [PMID: 35011573 PMCID: PMC8750259 DOI: 10.3390/cells11010006] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2021] [Revised: 12/17/2021] [Accepted: 12/19/2021] [Indexed: 12/18/2022] Open
Abstract
The development over the past 50 years of a variety of cell lines and animal models has provided valuable tools to understand the pathophysiology of nephropathic cystinosis. Primary cultures from patient biopsies have been instrumental in determining the primary cause of cystine accumulation in the lysosomes. Immortalised cell lines have been established using different gene constructs and have revealed a wealth of knowledge concerning the molecular mechanisms that underlie cystinosis. More recently, the generation of induced pluripotent stem cells, kidney organoids and tubuloids have helped bridge the gap between in vitro and in vivo model systems. The development of genetically modified mice and rats have made it possible to explore the cystinotic phenotype in an in vivo setting. All of these models have helped shape our understanding of cystinosis and have led to the conclusion that cystine accumulation is not the only pathology that needs targeting in this multisystemic disease. This review provides an overview of the in vitro and in vivo models available to study cystinosis, how well they recapitulate the disease phenotype, and their limitations.
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Affiliation(s)
- Pang Yuk Cheung
- Department of Molecular Medicine and Pathology, The University of Auckland, Auckland 1142, New Zealand; (P.Y.C.); (A.J.D.)
| | - Patrick T. Harrison
- Department of Physiology, BioSciences Institute, University College Cork, T12 XF62 Cork, Ireland;
| | - Alan J. Davidson
- Department of Molecular Medicine and Pathology, The University of Auckland, Auckland 1142, New Zealand; (P.Y.C.); (A.J.D.)
| | - Jennifer A. Hollywood
- Department of Molecular Medicine and Pathology, The University of Auckland, Auckland 1142, New Zealand; (P.Y.C.); (A.J.D.)
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Cheung WW, Hao S, Zheng R, Wang Z, Gonzalez A, Zhou P, Hoffman HM, Mak RH. Targeting interleukin-1 for reversing fat browning and muscle wasting in infantile nephropathic cystinosis. J Cachexia Sarcopenia Muscle 2021; 12:1296-1311. [PMID: 34196133 PMCID: PMC8517356 DOI: 10.1002/jcsm.12744] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 05/05/2021] [Accepted: 06/08/2021] [Indexed: 11/07/2022] Open
Abstract
BACKGROUND Ctns-/- mice, a mouse model of infantile nephropathic cystinosis, exhibit hypermetabolism with adipose tissue browning and profound muscle wasting. Inflammatory cytokines such as interleukin (IL)-1 trigger inflammatory cascades and may be an important cause for cachexia. We employed genetic and pharmacological approaches to investigate the effects of IL-1 blockade in Ctns-/- mice. METHODS We generated Ctns-/- Il1β-/- mice, and we treated Ctns-/- and wild-type control mice with IL-1 receptor antagonist, anakinra (2.5 mg/kg/day, IP) or saline as vehicle for 6 weeks. In each of these mouse lines, we characterized the cachexia phenotype consisting of anorexia, loss of weight, fat mass and lean mass, elevation of metabolic rate, and reduced in vivo muscle function (rotarod activity and grip strength). We quantitated energy homeostasis by measuring the protein content of uncoupling proteins (UCPs) and adenosine triphosphate in adipose tissue and skeletal muscle. We measured skeletal muscle fiber area and intramuscular fatty infiltration. We also studied expression of molecules regulating adipose tissue browning and muscle mass metabolism. Finally, we evaluated the impact of anakinra on the muscle transcriptome in Ctns-/- mice. RESULTS Skeletal muscle expression of IL-1β was significantly elevated in Ctns-/- mice relative to wild-type control mice. Cachexia was completely normalized in Ctns-/- Il1β-/- mice relative to Ctns-/- mice. We showed that anakinra attenuated the cachexia phenotype in Ctns-/- mice. Anakinra normalized UCPs and adenosine triphosphate content of adipose tissue and muscle in Ctns-/- mice. Anakinra attenuated aberrant expression of beige adipose cell biomarkers (UCP-1, CD137, Tmem26, and Tbx1) and molecules implicated in adipocyte tissue browning (Cox2/Pgf2α, Tlr2, Myd88, and Traf6) in inguinal white adipose tissue in Ctns-/- mice. Moreover, anakinra normalized gastrocnemius weight and fiber size and attenuated muscle fat infiltration in Ctns-/- mice. This was accompanied by correction of the increased muscle wasting signalling pathways (increased protein content of ERK1/2, JNK, p38 MAPK, and nuclear factor-κB p65 and mRNA expression of Atrogin-1 and Myostatin) and the decreased myogenesis process (decreased mRNA expression of MyoD and Myogenin) in the gastrocnemius muscle of Ctns-/- mice. Previously, we identified the top 20 differentially expressed skeletal muscle genes in Ctns-/- mice by RNAseq. Aberrant expression of these 20 genes have been implicated in muscle wasting, increased energy expenditure, and lipolysis. We showed that anakinra attenuated 12 of those top 20 differentially expressed muscle genes in Ctns-/- mice. CONCLUSIONS Anakinra may provide a targeted novel therapy for patients with infantile nephropathic cystinosis.
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Affiliation(s)
- Wai W. Cheung
- Division of Pediatric Nephrology, Department of Pediatrics, Rady Children's Hospital San DiegoUniversity of California, San DiegoLa JollaCAUSA
| | - Sheng Hao
- Department of Nephrology and Rheumatology, Shanghai Children's HospitalShanghai Jiao Tong UniversityShanghaiChina
| | - Ronghao Zheng
- Department of Pediatric Nephrology, Rheumatology, and Immunology, Maternal and Child Health Hospital of Hubei Province, Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina
| | - Zhen Wang
- Department of Pediatrics, Shanghai General HospitalShanghai Jiao Tong UniversityShanghaiChina
| | - Alex Gonzalez
- Division of Pediatric Nephrology, Department of Pediatrics, Rady Children's Hospital San DiegoUniversity of California, San DiegoLa JollaCAUSA
| | - Ping Zhou
- Sichuan Provincial Hospital for Women and ChildrenAffiliated Women and Children's Hospital of Chengdu Medical CollegeChengduChina
| | - Hal M. Hoffman
- Department of PediatricsUniversity of California, San DiegoLa JollaCAUSA
| | - Robert H. Mak
- Division of Pediatric Nephrology, Department of Pediatrics, Rady Children's Hospital San DiegoUniversity of California, San DiegoLa JollaCAUSA
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12
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Gonzalez A, Cheung WW, Perens EA, Oliveira EA, Gertler A, Mak RH. A Leptin Receptor Antagonist Attenuates Adipose Tissue Browning and Muscle Wasting in Infantile Nephropathic Cystinosis-Associated Cachexia. Cells 2021; 10:1954. [PMID: 34440723 PMCID: PMC8393983 DOI: 10.3390/cells10081954] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 07/19/2021] [Accepted: 07/24/2021] [Indexed: 12/12/2022] Open
Abstract
Mice lacking the functional cystinosin gene (Ctns-/-), a model of infantile nephropathic cystinosis (INC), exhibit the cachexia phenotype with adipose tissue browning and muscle wasting. Elevated leptin signaling is an important cause of chronic kidney disease-associated cachexia. The pegylated leptin receptor antagonist (PLA) binds to but does not activate the leptin receptor. We tested the efficacy of this PLA in Ctns-/- mice. We treated 12-month-old Ctns-/- mice and control mice with PLA (7 mg/kg/day, IP) or saline as a vehicle for 28 days. PLA normalized food intake and weight gain, increased fat and lean mass, decreased metabolic rate and improved muscle function. It also attenuated perturbations of energy homeostasis in adipose tissue and muscle in Ctns-/- mice. PLA attenuated adipose tissue browning in Ctns-/- mice. PLA increased gastrocnemius weight and fiber size as well as attenuated muscle fat infiltration in Ctns-/- mice. This was accompanied by correcting the increased expression of muscle wasting signaling while promoting the decreased expression of myogenesis in gastrocnemius of Ctns-/- mice. PLA attenuated aberrant expressed muscle genes that have been associated with muscle atrophy, increased energy expenditure and lipolysis in Ctns-/- mice. Leptin antagonism may represent a viable therapeutic strategy for adipose tissue browning and muscle wasting in INC.
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MESH Headings
- Adipose Tissue, Brown/drug effects
- Adipose Tissue, Brown/metabolism
- Adipose Tissue, Brown/pathology
- Adipose Tissue, White/drug effects
- Adipose Tissue, White/metabolism
- Adipose Tissue, White/pathology
- Amino Acid Transport Systems, Neutral/genetics
- Amino Acid Transport Systems, Neutral/metabolism
- Animals
- Body Composition/drug effects
- Cachexia/etiology
- Cachexia/metabolism
- Cachexia/pathology
- Cachexia/prevention & control
- Cystinosis/complications
- Cystinosis/drug therapy
- Cystinosis/metabolism
- Cystinosis/pathology
- Disease Models, Animal
- Hormone Antagonists/pharmacology
- Male
- Mice, Inbred C57BL
- Mice, Knockout
- Muscle, Skeletal/drug effects
- Muscle, Skeletal/metabolism
- Muscle, Skeletal/pathology
- Muscular Atrophy/etiology
- Muscular Atrophy/metabolism
- Muscular Atrophy/pathology
- Muscular Atrophy/prevention & control
- Receptors, Leptin/antagonists & inhibitors
- Receptors, Leptin/metabolism
- Signal Transduction
- Mice
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Affiliation(s)
- Alex Gonzalez
- Division of Pediatric Nephrology, Rady Children’s Hospital, University of California, San Diego, CA 92093-0831, USA; (A.G.); (W.W.C.); (E.A.P.); (E.A.O.)
| | - Wai W. Cheung
- Division of Pediatric Nephrology, Rady Children’s Hospital, University of California, San Diego, CA 92093-0831, USA; (A.G.); (W.W.C.); (E.A.P.); (E.A.O.)
| | - Elliot A. Perens
- Division of Pediatric Nephrology, Rady Children’s Hospital, University of California, San Diego, CA 92093-0831, USA; (A.G.); (W.W.C.); (E.A.P.); (E.A.O.)
| | - Eduardo A. Oliveira
- Division of Pediatric Nephrology, Rady Children’s Hospital, University of California, San Diego, CA 92093-0831, USA; (A.G.); (W.W.C.); (E.A.P.); (E.A.O.)
- Health Sciences Postgraduate Program, School of Medicine, Federal University of Minas Gerais (UFMG), Belo Horizonte 30130-100, MG, Brazil
| | - Arieh Gertler
- Institute of Biochemistry, Food Science and Nutrition, Hebrew University of Jerusalem, Rehovot 7610001, Israel;
| | - Robert H. Mak
- Division of Pediatric Nephrology, Rady Children’s Hospital, University of California, San Diego, CA 92093-0831, USA; (A.G.); (W.W.C.); (E.A.P.); (E.A.O.)
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13
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Cheung WW, Zheng R, Hao S, Wang Z, Gonzalez A, Zhou P, Hoffman HM, Mak RH. The role of IL-1 in adipose browning and muscle wasting in CKD-associated cachexia. Sci Rep 2021; 11:15141. [PMID: 34302016 PMCID: PMC8302616 DOI: 10.1038/s41598-021-94565-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Accepted: 06/29/2021] [Indexed: 10/25/2022] Open
Abstract
Cytokines such as IL-6, TNF-α and IL-1β trigger inflammatory cascades which may play a role in the pathogenesis of chronic kidney disease (CKD)-associated cachexia. CKD was induced by 5/6 nephrectomy in mice. We studied energy homeostasis in Il1β-/-/CKD, Il6-/-/CKD and Tnfα-/-/CKD mice and compared with wild type (WT)/CKD controls. Parameters of cachexia phenotype were completely normalized in Il1β-/-/CKD mice but were only partially rescued in Il6-/-/CKD and Tnfα-/-/CKD mice. We tested the effects of anakinra, an IL-1 receptor antagonist, on CKD-associated cachexia. WT/CKD mice were treated with anakinra (2.5 mg/kg/day, IP) or saline for 6 weeks and compared with WT/Sham controls. Anakinra normalized food intake and weight gain, fat and lean mass content, metabolic rate and muscle function, and also attenuated molecular perturbations of energy homeostasis in adipose tissue and muscle in WT/CKD mice. Anakinra decreased serum and muscle expression of IL-6, TNF-α and IL-1β in WT/CKD mice. Anakinra attenuated browning of white adipose tissue in WT/CKD mice. Moreover, anakinra normalized gastrocnemius weight and fiber size as well as attenuated muscle fat infiltration in WT/CKD mice. This was accompanied by correcting the increased muscle wasting signaling pathways while promoting the decreased myogenesis process in gastrocnemius of WT/CKD mice. We performed qPCR analysis for the top 20 differentially expressed muscle genes previously identified via RNAseq analysis in WT/CKD mice versus controls. Importantly, 17 differentially expressed muscle genes were attenuated in anakinra treated WT/CKD mice. In conclusion, IL-1 receptor antagonism may represent a novel targeted treatment for adipose tissue browning and muscle wasting in CKD.
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Affiliation(s)
- Wai W Cheung
- Division of Pediatric Nephrology, Rady Children's Hospital, University of California, San Diego, 9500 Gilman Drive, MC 0831, La Jolla, CA, 92093-0831, USA
| | - Ronghao Zheng
- Department of Pediatric Nephrology, Rheumatology, and Immunology, Maternal and Child Health Hospital of Hubei Province, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Sheng Hao
- Department of Nephrology and Rheumatology, Shanghai Children's Hospital, Shanghai Jiao Tong University, Shanghai, China
| | - Zhen Wang
- Department of Pediatrics, Shanghai General Hospital, Shanghai Jiao Tong University, Shanghai, China
| | - Alex Gonzalez
- Division of Pediatric Nephrology, Rady Children's Hospital, University of California, San Diego, 9500 Gilman Drive, MC 0831, La Jolla, CA, 92093-0831, USA
| | - Ping Zhou
- Sichuan Provincial Hospital for Women and Children, and Affiliated Women and Children's Hospital of Chengdu Medical College, Sichuan, China
| | - Hal M Hoffman
- Department of Pediatrics, University of California, San Diego, USA
| | - Robert H Mak
- Division of Pediatric Nephrology, Rady Children's Hospital, University of California, San Diego, 9500 Gilman Drive, MC 0831, La Jolla, CA, 92093-0831, USA.
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14
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Cheung WW, Ding W, Hoffman HM, Wang Z, Hao S, Zheng R, Gonzalez A, Zhan JY, Zhou P, Li S, Esparza MC, Lieber RL, Mak RH. Vitamin D ameliorates adipose browning in chronic kidney disease cachexia. Sci Rep 2020; 10:14175. [PMID: 32843714 PMCID: PMC7447759 DOI: 10.1038/s41598-020-70190-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 07/21/2020] [Indexed: 12/15/2022] Open
Abstract
Patients with chronic kidney disease (CKD) are often 25(OH)D3 and 1,25(OH)2D3 insufficient. We studied whether vitamin D repletion could correct aberrant adipose tissue and muscle metabolism in a mouse model of CKD-associated cachexia. Intraperitoneal administration of 25(OH)D3 and 1,25(OH)2D3 (75 μg/kg/day and 60 ng/kg/day respectively for 6 weeks) normalized serum concentrations of 25(OH)D3 and 1,25(OH)2D3 in CKD mice. Vitamin D repletion stimulated appetite, normalized weight gain, and improved fat and lean mass content in CKD mice. Vitamin D supplementation attenuated expression of key molecules involved in adipose tissue browning and ameliorated expression of thermogenic genes in adipose tissue and skeletal muscle in CKD mice. Furthermore, repletion of vitamin D improved skeletal muscle fiber size and in vivo muscle function, normalized muscle collagen content and attenuated muscle fat infiltration as well as pathogenetic molecular pathways related to muscle mass regulation in CKD mice. RNAseq analysis was performed on the gastrocnemius muscle. Ingenuity Pathway Analysis revealed that the top 12 differentially expressed genes in CKD were correlated with impaired muscle and neuron regeneration, enhanced muscle thermogenesis and fibrosis. Importantly, vitamin D repletion normalized the expression of those 12 genes in CKD mice. Vitamin D repletion may be an effective therapeutic strategy for adipose tissue browning and muscle wasting in CKD patients.
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MESH Headings
- Adipocytes, Beige/drug effects
- Adipocytes, Beige/metabolism
- Adipocytes, Brown/metabolism
- Adipocytes, White/metabolism
- Animals
- Cachexia/drug therapy
- Cachexia/etiology
- Cachexia/physiopathology
- Calcifediol/blood
- Calcifediol/deficiency
- Calcifediol/pharmacology
- Calcifediol/therapeutic use
- Calcitriol/blood
- Calcitriol/deficiency
- Calcitriol/pharmacology
- Calcitriol/therapeutic use
- Disease Models, Animal
- Eating/drug effects
- Fibrosis/genetics
- Gene Expression Regulation/drug effects
- Hand Strength
- Mice
- Mice, Inbred C57BL
- Muscle Fibers, Skeletal/drug effects
- Muscle Fibers, Skeletal/pathology
- Nephrectomy
- Parathyroid Hormone/blood
- RNA, Messenger/biosynthesis
- Renal Insufficiency, Chronic/blood
- Renal Insufficiency, Chronic/complications
- Renal Insufficiency, Chronic/drug therapy
- Rotarod Performance Test
- Sequence Analysis, RNA
- Thermogenesis/drug effects
- Weight Gain/drug effects
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Affiliation(s)
- Wai W Cheung
- Pediatric Nephrology, Rady Children's Hospital San Diego, University of California, San Diego, USA
| | - Wei Ding
- Division of Nephrology, School of Medicine, Shanghai Ninth People's Hospital, Shanghai Jiaotong University, Shanghai, China
| | - Hal M Hoffman
- Department of Pediatrics, University of California, San Diego, USA
| | - Zhen Wang
- Department of Pediatrics, Shanghai General Hospital, Shanghai Jiao Tong University, Shanghai, China
| | - Sheng Hao
- Department of Nephrology and Rheumatology, Shanghai Children's Hospital, Shanghai Jiao Tong University, Shanghai, China
| | - Ronghao Zheng
- Department of Pediatrics, Hubei Maternal and Child Health Hospital, Wuhan, China
| | - Alex Gonzalez
- Pediatric Nephrology, Rady Children's Hospital San Diego, University of California, San Diego, USA
| | - Jian-Ying Zhan
- Children's Hospital, Zhejiang University, Hangzhou, China
| | - Ping Zhou
- Department of Pediatrics, The Second Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Shiping Li
- College of Bioscience and Biotechnology, Yangzhou University, Yangzhou, China
| | - Mary C Esparza
- Department of Orthopedic Surgery, University of California, San Diego, USA
| | - Richard L Lieber
- Shirley Ryan AbilityLab and Northwestern University, Chicago, USA
| | - Robert H Mak
- Pediatric Nephrology, Rady Children's Hospital San Diego, University of California, San Diego, USA.
- Division of Pediatric Nephrology, Department of Pediatrics, University of California, San Diego, 9500 Gilman Drive, MC 0831, La Jolla, CA, 92093-0831, USA.
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15
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Cheung WW, Hao S, Wang Z, Ding W, Zheng R, Gonzalez A, Zhan J, Zhou P, Li S, Esparza MC, Hoffman HM, Lieber RL, Mak RH. Vitamin D repletion ameliorates adipose tissue browning and muscle wasting in infantile nephropathic cystinosis-associated cachexia. J Cachexia Sarcopenia Muscle 2020; 11:120-134. [PMID: 31721480 PMCID: PMC7015252 DOI: 10.1002/jcsm.12497] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Revised: 07/30/2019] [Accepted: 08/25/2019] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Ctns-/- mice, a mouse model of infantile nephropathic cystinosis, exhibit hypermetabolism with adipose tissue browning and profound muscle wasting. Ctns-/- mice are 25(OH)D3 and 1,25(OH)2 D3 insufficient. We investigated whether vitamin D repletion could ameliorate adipose tissue browning and muscle wasting in Ctns-/- mice. METHODS Twelve-month-old Ctns-/- mice and wild-type controls were treated with 25(OH)D3 and 1,25(OH)2 D3 (75 μg/kg/day and 60 ng/kg/day, respectively) or an ethylene glycol vehicle for 6 weeks. Serum chemistry and parameters of energy homeostasis were measured. We quantitated total fat mass and studied expression of molecules regulating adipose tissue browning, energy metabolism, and inflammation. We measured lean mass content, skeletal muscle fibre size, in vivo muscle function (grip strength and rotarod activity), and expression of molecules regulating muscle metabolism. We also analysed the transcriptome of skeletal muscle in Ctns-/- mice using RNAseq. RESULTS Supplementation of 25(OH)D3 and 1,25(OH)2 D3 normalized serum concentration of 25(OH)D3 and 1,25(OH)2 D3 in Ctns-/- mice, respectively. Repletion of vitamin D partially or fully normalized food intake, weight gain, gain of fat, and lean mass, improved energy homeostasis, and attenuated perturbations of uncoupling proteins and adenosine triphosphate content in adipose tissue and muscle in Ctns-/- mice. Vitamin D repletion attenuated elevated expression of beige adipose cell biomarkers (UCP-1, CD137, Tmem26, and Tbx1) as well as aberrant expression of molecules implicated in adipose tissue browning (Cox2, Pgf2α, and NF-κB pathway) in inguinal white adipose tissue in Ctns-/- mice. Vitamin D repletion normalized skeletal muscle fibre size and improved in vivo muscle function in Ctns-/- mice. This was accompanied by correcting the increased muscle catabolic signalling (increased protein contents of IL-1β, IL-6, and TNF-α as well as an increased gene expression of Murf-2, atrogin-1, and myostatin) and promoting the decreased muscle regeneration and myogenesis process (decreased gene expression of Igf1, Pax7, and MyoD) in skeletal muscles of Ctns-/- mice. Muscle RNAseq analysis revealed aberrant gene expression profiles associated with reduced muscle and neuron regeneration, increased energy metabolism, and fibrosis in Ctns-/- mice. Importantly, repletion of 25(OH)D3 and 1,25(OH)2 D3 normalized the top 20 differentially expressed genes in Ctns-/- mice. CONCLUSIONS We report the novel findings that correction of 25(OH)D3 and 1,25(OH)2 D3 insufficiency reverses cachexia and may improve quality of life by restoring muscle function in an animal model of infantile nephropathic cystinosis. Mechanistically, vitamin D repletion attenuates adipose tissue browning and muscle wasting in Ctns-/- mice via multiple cellular and molecular mechanisms.
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Affiliation(s)
- Wai W. Cheung
- Pediatric NephrologyRady Children's Hospital—San Diego, University of California, San DiegoSan DiegoCAUSA
| | - Sheng Hao
- Department of Nephrology and RheumatologyShanghai Children's Hospital, Shanghai Jiao Tong UniversityShanghaiChina
| | - Zhen Wang
- Department of PediatricsShanghai General Hospital, Shanghai Jiao Tong UniversityShanghaiChina
| | - Wei Ding
- Division of NephrologyShanghai 9th People's Hospital, Shanghai Jiao Tong UniversityShanghaiChina
| | - Ronghao Zheng
- Department of Pediatric Nephrology, Rheumatology, and ImmunologyMaternal and Child Health Hospital of Hubei Province, Tongji Medical College, Huazhong University of Science and TechnologyWuhanChina
| | - Alex Gonzalez
- Pediatric NephrologyRady Children's Hospital—San Diego, University of California, San DiegoSan DiegoCAUSA
| | | | - Ping Zhou
- Department of PediatricsThe 2 Hospital of Harbin Medical UniversityHarbinChina
| | - Shiping Li
- College of Bioscience and BiotechnologyYangzhou UniversityYangzhouChina
| | - Mary C. Esparza
- Department of Orthopedic SurgeryUniversity of California, San DiegoSan DiegoCAUSA
| | - Hal M. Hoffman
- Department of PediatricsUniversity of California, San DiegoSan DiegoCAUSA
| | - Richard L. Lieber
- Department of Orthopedic SurgeryUniversity of California, San DiegoSan DiegoCAUSA
- Rehabilitation Institute of ChicagoChicagoILUSA
| | - Robert H. Mak
- Pediatric NephrologyRady Children's Hospital—San Diego, University of California, San DiegoSan DiegoCAUSA
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Brown Adipocyte and Splenocyte Co-Culture Maintains Regulatory T Cell Subset in Intermittent Hypobaric Conditions. Tissue Eng Regen Med 2019; 16:539-548. [PMID: 31624708 PMCID: PMC6778593 DOI: 10.1007/s13770-019-00205-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Revised: 06/15/2019] [Accepted: 07/16/2019] [Indexed: 11/02/2022] Open
Abstract
Background Brown adipocytes have thermogenic characteristics in neonates and elicit anti-inflammatory responses. We postulated that thermogenic brown adipocytes produce distinctive intercellular effects in a hypobaric state. The purpose of this study is to analyze the correlation between brown adipocyte and regulatory T cell (Treg) expression under intermittent hypobaric conditions. Methods Brown and white adipocytes were harvested from the interscapular and flank areas of C57BL6 mice, respectively. Adipocytes were cultured with syngeneic splenocytes after isolation and differentiation. Intermittent hypobaric conditions were generated using cyclic negative pressure application for 48 h in both groups of adipocytes. Expression levels of Tregs (CD4 + CD25 + Foxp3 + T cells), cytokines [tumor necrosis factor-α (TNF-α) and interleukin-10 (IL-10), and the programmed death-ligand 1 (PD-L1)] co-inhibitory ligand were examined. Results Splenocytes, cultured with brown and white adipocytes, exhibited comparable Treg expression in a normobaric state. Under hypobaric conditions, brown adipocytes maintained a subset of Tregs. However, a decrease in Tregs was found in the white adipocyte group. TNF-α levels increased in both groups under hypobaric conditions. In the brown adipocyte group, anti-inflammatory IL-10 expression increased significantly; meanwhile, IL-10 expression decreased in the white adipocyte group. PD-L1 levels increased more significantly in brown adipocytes than in white adipocytes under hypobaric conditions. Conclusion Both brown and white adipocytes support Treg expression when they are cultured with splenocytes. Of note, brown adipocytes maintained Treg expression in intermittent hypobaric conditions. Anti-inflammatory cytokines and co-inhibitory ligands mediate the immunomodulatory effects of brown adipocytes under altered atmospheric conditions. Brown adipocytes showed the feasibility as a source of adjustment in physical stresses.
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Koppe L, Fouque D, Kalantar‐Zadeh K. Kidney cachexia or protein-energy wasting in chronic kidney disease: facts and numbers. J Cachexia Sarcopenia Muscle 2019; 10:479-484. [PMID: 30977979 PMCID: PMC6596400 DOI: 10.1002/jcsm.12421] [Citation(s) in RCA: 116] [Impact Index Per Article: 23.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Weight loss and homeostatic disturbances of both energy and protein balances are characteristics of several illnesses including cancer, heart failure, and chronic kidney disease (CKD). Different definitions have been used to describe this deleterious process. The term protein-energy wasting (PEW) has been proposed for CKD patients by the International Society of Renal Nutrition and Metabolism. METHODS We searched the publication in Medline from February 2008 to September 2018 using PEW or cachexia in their title. RESULTS Since its inception, the term PEW has been exceptionally successful, highlighted by 327 original publications referenced in PubMed over 10 years. Using this classification, several studies have confirmed that PEW is among the strongest predictors of mortality in CKD patients [hazard ratio of 3.03; confidence interval of 1.69-5.26 in 1068 haemodialysis patients and 1.40 (1.04-1.89) in 1487 non-dialysed patients across PEW stages 0 to 4]. Based on this classification, prevalence of PEW is 28% to 54% among 16 434 adults undergoing maintenance dialysis. PEW prevalence increases when renal function declines, that is, from <2% in CKD stages 1-2 to 11-54% in CKD stages 3-5. A more general definition of cachexia for all chronic diseases proposed by the Society on Sarcopenia, Cachexia and Wasting Disorders was also published concurrently. In the CKD area, we found 180 publications using 'cachexia' underlining that some confusion or overlap may exist. The definitions of PEW and cachexia are somewhat similar, and the main difference is that a loss of body weight >5% is a mandatory criterion for cachexia but supportive for PEW. CONCLUSIONS The recent understanding of cachexia physiopathology during CKD progression suggests that PEW and cachexia are closely related and that PEW corresponds the initial state of a continuous process that leads to cachexia, implicating the same metabolic pathways as in other chronic diseases. Despite the success of the definition of PEW, using a more uniform term such as 'kidney disease cachexia' could be more helpful to design future research through collaborative groups of researchers with focus on cachexia.
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Affiliation(s)
- Laetitia Koppe
- Centre Hospitalier Lyon‐SudUniv Lyon, CarMeN, Dept NephrologyPierre‐BéniteFrance
| | - Denis Fouque
- Centre Hospitalier Lyon‐SudUniv Lyon, CarMeN, Dept NephrologyPierre‐BéniteFrance
| | - Kamyar Kalantar‐Zadeh
- Harold Simmons Center for Kidney Disease Research and Epidemiology, Division of Nephrology and HypertensionUniversity of California, Irvine, School of Medicine, OrangeIrvineCAUSA
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Zhang J, He J, Johnson JL, Rahman F, Gavathiotis E, Cuervo AM, Catz SD. Chaperone-Mediated Autophagy Upregulation Rescues Megalin Expression and Localization in Cystinotic Proximal Tubule Cells. Front Endocrinol (Lausanne) 2019; 10:21. [PMID: 30774622 PMCID: PMC6367655 DOI: 10.3389/fendo.2019.00021] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Accepted: 01/14/2019] [Indexed: 01/16/2023] Open
Abstract
Cystinosis is a lysosomal storage disorder caused by defects in CTNS, the gene that encodes the lysosomal cystine transporter cystinosin. Patients with nephropathic cystinosis are characterized by endocrine defects, defective proximal tubule cell (PTC) function, the development of Fanconi syndrome and, eventually, end-stage renal disease. Kidney disease is developed despite the use of cysteamine, a drug that decreases lysosomal cystine overload but fails to correct overload-independent defects. Chaperone-mediated autophagy (CMA), a selective form of autophagy, is defective in cystinotic mouse fibroblasts, and treatment with cysteamine is unable to correct CMA defects in vivo, but whether the vesicular trafficking mechanisms that lead to defective CMA in cystinosis are manifested in human PTCs is not currently known and whether PTC-specific mechanisms are corrected upon CMA upregulation remains to be elucidated. Here, using CRISPR-Cas9 technology, we develop a new human PTC line with defective cystinosin expression (CTNS-KO PTCs). We show that the expression and localization of the CMA receptor, LAMP2A, is defective in CTNS-KO PTCs. The expression of the lipidated form of LC3B, a marker for another form of autophagy (macroautophagy), is decreased in CTNS-KO PTCs indicating decreased autophagosome numbers under basal conditions. However, the autophagic flux is functional, as measured by induction by starvation or by blockage using the v-ATPase inhibitor bafilomycin A, and by degradation of the macroautophagy substrate SQSTM1 under starvation and proteasome-inhibited conditions. Previous studies showed that LAMP2A accumulates in Rab11-positive vesicles in cystinotic cells. Here, we show defective Rab11 expression, localization and trafficking in CTNS-KO PTCs as determined by confocal microscopy, immunoblotting and TIRFM. We also show that both Rab11 expression and trafficking in cystinotic PTCs are rescued by the upregulation of CMA using small-molecule CMA activators. Cystinotic PTCs are characterized by PTC de-differentiation accompanied by loss of the endocytic receptor megalin, and megalin recycling is regulated by Rab11. Here we show that megalin plasma membrane localization is defective in CTNS-KO PTCs and its expression is rescued by treatment with CMA activators. Altogether, our data support that CMA upregulation has the potential to improve PTC function in cystinosis.
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Affiliation(s)
- Jinzhong Zhang
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, United States
| | - Jing He
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, United States
| | - Jennifer L. Johnson
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, United States
| | - Farhana Rahman
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, United States
| | - Evripidis Gavathiotis
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY, United States
| | - Ana Maria Cuervo
- Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, NY, United States
| | - Sergio D. Catz
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, United States
- *Correspondence: Sergio D. Catz
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Shewan LG. Contemporary publication patterns in the Journal of Cachexia, Sarcopenia and Muscle by type and sub-speciality: facts and numbers. J Cachexia Sarcopenia Muscle 2018; 9:1192-1195. [PMID: 30697979 PMCID: PMC6351672 DOI: 10.1002/jcsm.12385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Affiliation(s)
- Louise G. Shewan
- Sydney Medical SchoolUniversity of SydneySydneyNew South Wales2006Australia
- University of MelbourneParkvilleVictoria3010Australia
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Abstract
Introduction Cachexia is a common complication of many and varied chronic disease processes, yet it has received very little attention as an area of clinical research effort until recently. We sought to survey the contemporary literature on published research into cachexia to define where it is being published and the proportion of output classified into the main types of research output. Methods I searched the PubMed listings under the topic research term "cachexia" and related terms for articles published in the calendar years of 2015 and 2016, regardless of language. Searches were conducted and relevant papers extracted by two observers, and disagreements were resolved by consensus. Results There were 954 publications, 370 of which were review articles or commentaries, 254 clinical observations or non-randomised trials, 246 original basic science reports and only 26 were randomised controlled trials. These articles were published in 478 separate journals but with 36% of them being published in a core set of 23 journals. The H-index of these papers was 25 and there were 147 papers with 10 or more citations. Of the top 100 cited papers, 25% were published in five journals. Of the top cited papers, 48% were review articles, 18% were original basic science, and 7% were randomised clinical trials. Discussion This analysis shows a steady but modest increase in publications concerning cachexia with a strong pipeline of basic science research but still a relative lack of randomised clinical trials, with none exceeding 1000 patients. Research in cachexia is still in its infancy, but the solid basic science effort offers hope that translation into randomised controlled clinical trials may eventually lead to effective therapies for this troubling and complex clinical disease process.
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Cherqui S, Courtoy PJ. The renal Fanconi syndrome in cystinosis: pathogenic insights and therapeutic perspectives. Nat Rev Nephrol 2016; 13:115-131. [PMID: 27990015 DOI: 10.1038/nrneph.2016.182] [Citation(s) in RCA: 106] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Cystinosis is an autosomal recessive metabolic disease that belongs to the family of lysosomal storage disorders. It is caused by a defect in the lysosomal cystine transporter, cystinosin, which results in an accumulation of cystine in all organs. Despite the ubiquitous expression of cystinosin, a renal Fanconi syndrome is often the first manifestation of cystinosis, usually presenting within the first year of life and characterized by the early and severe dysfunction of proximal tubule cells, highlighting the unique vulnerability of this cell type. The current therapy for cystinosis, cysteamine, facilitates lysosomal cystine clearance and greatly delays progression to kidney failure but is unable to correct the Fanconi syndrome. This Review summarizes decades of studies that have fostered a better understanding of the pathogenesis of the renal Fanconi syndrome associated with cystinosis. These studies have unraveled some of the early molecular changes that occur before the onset of tubular atrophy and identified a role for cystinosin beyond cystine transport, in endolysosomal trafficking and proteolysis, lysosomal clearance, autophagy and the regulation of energy balance. These studies have also led to the identification of new potential therapeutic targets and here, we outline the potential role of stem cell therapy for cystinosis and provide insights into the mechanism of haematopoietic stem cell-mediated kidney protection.
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Affiliation(s)
- Stephanie Cherqui
- Department of Pediatrics, Division of Genetics, University of California San Diego, 9500 Gilman Drive, MC 0734, La Jolla, California 92093-0734, USA
| | - Pierre J Courtoy
- Cell biology, de Duve Institute and Université catholique de Louvain, UCL-Brussels, 75 Avenue Hippocrate, B-1200 Brussels, Belgium
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Cheung WW, Cherqui S, Ding W, Esparza M, Zhou P, Shao J, Lieber RL, Mak RH. Muscle wasting and adipose tissue browning in infantile nephropathic cystinosis. J Cachexia Sarcopenia Muscle 2016; 7:152-64. [PMID: 27493869 PMCID: PMC4864942 DOI: 10.1002/jcsm.12056] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Revised: 04/21/2015] [Accepted: 06/03/2015] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Muscle wasting is a common complication in patients with infantile nephropathic cystinosis, but its mechanism and association with energy metabolism is not known. We define the metabolic phenotype in Ctns(-/-) mice, an established murine model of infantile nephropathic cystinosis, with focus on muscle wasting and energy homeostasis. METHODS Male Ctns(-/-) mice and wild-type (WT) controls were studied at 1, 4, 9, and 12 months of age. As Ctns(-/-) mice started to develop chronic kidney disease (CKD) at 9 months of age, 9- and 12-month-old Ctns(-/-) mice were also compared with age-matched WT mice with CKD. Serum and urine chemistry and energy homeostasis parameters were measured. Skeletal muscle histomorphometry and in vivo muscle function were measured. We studied expression of genes involved in muscle mass regulation, thermogenesis, energy metabolism, adipogenesis, and adipose tissue browning in Ctns(-/-) mice. RESULTS Ctns(-/-) mice showed loss of weight and lean mass and increased energy expenditure. Ctns(-/-) mice exhibited abnormal energy homeostasis before the onset of their CKD. Food intake in Ctns(-/-) mice was comparable with age-matched WT controls. However, significantly lower total body mass starting at 1 month of age and increased energy expenditure at 4 months of age preceded the onset of CKD at 9 months of age in Ctns(-/-) mice. Muscle accept content in 1- and 4-month-old Ctns(-/-) mice was significantly lower than that in age-matched WT controls. At 12 months of age, muscle fibre area and in vivo muscle strength was reduced in Ctns(-/-) mice than that in WT or CKD controls. Muscle wasting in Ctns(-/-) mice was associated with inhibition of myogenesis, activation of muscle proteolysis pathways, and overexpression of pro-inflammatory cytokines. Increased energy expenditure was associated with elevation of thermogenesis in skeletal muscle and adipose tissues. The development of beige adipocytes in Ctns(-/-) mice is a novel finding. Expression of beige adipose cell surface markers (CD137, Tmem26, and Tbx1) and uncoupling protein-1, which is a brown adipose tissue marker, was observed in inguinal white adipose tissue of Ctns(-/-) mice. Expression of key molecules implicated in the pathogenesis of adipose tissue browning (Cox2, cytochrome c oxidase subunit II; PGF2α, prostaglandin F2α; IL-1α, interleukin 1α; IL-6, interleukin 6; TNF-α, tumor necrosis factor α) was significantly increased in inguinal white adipose tissue of Ctns(-/-) mice than that in WT controls. CONCLUSION This study describes a mouse model of nephropathic cystinosis presenting with profound muscle wasting. The mechanism for hypermetabolism in Ctns(-/-) mice may involve up-regulation of thermogenesis pathways in skeletal muscle and adipose tissues. This study demonstrates, for the first time, the development of beige adipocytes in Ctns(-/-) mice. Understanding the underlying mechanisms of adipose tissue browning in cystinosis may lead to novel therapy.
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Affiliation(s)
- Wai W Cheung
- Department of Pediatrics University of California San Diego CA USA
| | | | - Wei Ding
- Department of Pediatrics University of California San Diego CA USA; Division of Nephrology, The 5th People's Hospital of Shanghai Fudan University Shanghai China
| | - Mary Esparza
- Department of Orthopedic Surgery University of California San Diego CA USA
| | - Ping Zhou
- Department of Pediatrics University of California San Diego CA USA; Department of Pediatrics The 2nd Hospital of Harbin Medical University Harbin China
| | - Jianhua Shao
- Department of Pediatrics University of California San Diego CA USA
| | - Richard L Lieber
- Department of Orthopedic Surgery University of California San Diego CA USA; Rehabilitation Institute of Chicago Chicago
| | - Robert H Mak
- Department of Pediatrics University of California San Diego CA USA
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