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1.
Int J Mol Sci ; 23(23)2022 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-36499637

RESUMO

Cachexia associated with chronic kidney disease (CKD) has been linked to GH resistance. In CKD, GH treatment enhances muscular performance. We investigated the impact of GH on cachexia brought on by CKD. CKD was induced by 5/6 nephrectomy in c57BL/6J mice. After receiving GH (10 mg/kg/day) or saline treatment for six weeks, CKD mice were compared to sham-operated controls. GH normalized metabolic rate, increased food intake and weight growth, and improved in vivo muscular function (rotarod and grip strength) in CKD mice. GH decreased uncoupling proteins (UCP)s and increased muscle and adipose tissue ATP content in CKD mice. GH decreased lipolysis of adipose tissue by attenuating expression and protein content of adipose triglyceride lipase and protein content of phosphorylated hormone-sensitive lipase in CKD mice. GH reversed the increased expression of beige adipocyte markers (UCP-1, CD137, Tmem26, Tbx1, Prdm16, Pgc1α, and Cidea) and molecules implicated in adipose tissue browning (Cox2/Pgf2α, Tlr2, Myd88, and Traf6) in CKD mice. Additionally, GH normalized the molecular markers of processes connected to muscle wasting in CKD, such as myogenesis and muscle regeneration. By using RNAseq, we previously determined the top 12 skeletal muscle genes differentially expressed between mice with CKD and control animals. These 12 genes' aberrant expression has been linked to increased muscle thermogenesis, fibrosis, and poor muscle and neuron regeneration. In this study, we demonstrated that GH restored 7 of the top 12 differentially elevated muscle genes in CKD mice. In conclusion, GH might be an effective treatment for muscular atrophy and browning of adipose tissue in CKD-related cachexia.


Assuntos
Hormônio do Crescimento Humano , Insuficiência Renal Crônica , Camundongos , Animais , Hormônio do Crescimento/metabolismo , Caquexia/etiologia , Caquexia/complicações , Tecido Adiposo/metabolismo , Atrofia Muscular/etiologia , Atrofia Muscular/complicações , Camundongos Endogâmicos C57BL , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/tratamento farmacológico , Insuficiência Renal Crônica/metabolismo , Músculo Esquelético/metabolismo , Hormônio do Crescimento Humano/metabolismo
2.
Kidney Int ; 96(2): 350-362, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30928021

RESUMO

Inflammation is involved in the pathogenesis of many disorders. However, the underlying mechanisms are often unknown. Here, we test whether cystinosin, the protein involved in cystinosis, is a critical regulator of galectin-3, a member of the ß-galactosidase binding protein family, during inflammation. Cystinosis is a lysosomal storage disorder and, despite ubiquitous expression of cystinosin, the kidney is the primary organ impacted by the disease. Cystinosin was found to enhance lysosomal localization and degradation of galectin-3. In Ctns-/- mice, a mouse model of cystinosis, galectin-3 is overexpressed in the kidney. The absence of galectin-3 in cystinotic mice ameliorates pathologic renal function and structure and decreases macrophage/monocyte infiltration in the kidney of the Ctns-/-Gal3-/- mice compared to Ctns-/- mice. These data strongly suggest that galectin-3 mediates inflammation involved in kidney disease progression in cystinosis. Furthermore, galectin-3 was found to interact with the pro-inflammatory cytokine Monocyte Chemoattractant Protein-1, which stimulates the recruitment of monocytes/macrophages, and proved to be significantly increased in the serum of Ctns-/- mice and also patients with cystinosis. Thus, our findings highlight a new role for cystinosin and galectin-3 interaction in inflammation and provide an additional mechanistic explanation for the kidney disease of cystinosis. This may lead to the identification of new drug targets to delay cystinosis progression.


Assuntos
Sistemas de Transporte de Aminoácidos Neutros/metabolismo , Cistinose/complicações , Síndrome de Fanconi/imunologia , Galectina 3/metabolismo , Inflamação/imunologia , Sistemas de Transporte de Aminoácidos Neutros/genética , Animais , Quimiocina CCL2/imunologia , Quimiocina CCL2/metabolismo , Cistina/metabolismo , Cistinose/imunologia , Cistinose/metabolismo , Cistinose/patologia , Modelos Animais de Doenças , Progressão da Doença , Síndrome de Fanconi/metabolismo , Síndrome de Fanconi/patologia , Feminino , Galectina 3/genética , Humanos , Inflamação/metabolismo , Inflamação/patologia , Túbulos Renais Proximais/imunologia , Túbulos Renais Proximais/patologia , Lisossomos/metabolismo , Macrófagos/imunologia , Masculino , Camundongos , Camundongos Knockout , Monócitos/imunologia , Proteólise
3.
Pediatr Nephrol ; 33(5): 789-798, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-28508131

RESUMO

Loss of lean body mass is a relevant component of the cachexia, or protein energy wasting (PEW), syndrome. Reduced muscle mass seems to be the most solid criterion for the presence of cachexia/PEW in patients with chronic kidney disease (CKD), and those with greater muscle mass loss have a higher risk of death. Children with CKD have many risk factors for lean mass and muscle wasting, including poor appetite, inflammation, growth hormone resistance, and metabolic acidosis. Mortality risks in patients with CKD increases as body mass index (BMI) and weight decreases. However, data regarding cachexia/PEW and muscle wasting in children with CKD is scarce due to lack of consensus in diagnostic criteria and an appropriate investigative methodology. Further research is urgently needed to address this important complication in the pediatric CKD setting, which may have fundamental impact on clinical outcomes.


Assuntos
Caquexia/etiologia , Insuficiência Renal Crônica/complicações , Adolescente , Caquexia/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Fatores de Risco , Adulto Jovem
4.
Kidney Int ; 92(2): 281-283, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28709594

RESUMO

Cachexia with wasting of muscle protein is a serious complication of chronic kidney disease (CKD). Muscle protein phosphorylation is a potential therapeutic target. Liu et al. reported that small C-terminal domain phosphatase (SCP) 4 was increased in muscles of patients and mice with CKD. Importantly, knockdown of SCP4 significantly ameliorated muscle wasting in CKD mice. Inhibition of SCP4 may represent a novel therapeutic intervention for muscle wasting in patients with CKD.


Assuntos
Insuficiência Renal Crônica , Fatores de Transcrição , Animais , Humanos , Camundongos , Proteínas Musculares , Atrofia Muscular , Monoéster Fosfórico Hidrolases
5.
J Am Soc Nephrol ; 25(1): 119-28, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24115476

RESUMO

Elevated serum leptin levels correlate with inflammation and predict changes in lean body mass in patients with CKD, and activation of the melanocortin system by leptin signaling mediates the pathophysiology of CKD-associated cachexia. We tested whether treatment with a pegylated leptin receptor antagonist (PLA) attenuates cachexia in mice with CKD. CKD and Sham mice received vehicle or PLA (2 or 7 mg/kg per day). At these doses, PLA did not influence serum leptin levels in mice. Treatment with 7 mg/kg per day PLA stimulated appetite and weight gain, improved lean mass and muscle function, reduced energy expenditure, and normalized the levels of hepatic TNF-α and IL-6 mRNA in mice with CKD. Furthermore, treatment with 7 mg/kg per day PLA attenuated the CKD-associated increase in the transcriptional and protein abundance of uncoupling proteins that mediates thermogenesis, and it normalized the molecular signatures of processes associated with muscle wasting in CKD, including proteolysis, myogenesis and muscle regeneration, and expression of proinflammatory muscle cytokines, such as IL-1α, -1ß, and -6 and TNF-α. Our results suggest that leptin antagonism may represent a viable therapeutic strategy for cachexia in CKD.


Assuntos
Caquexia/tratamento farmacológico , Caquexia/etiologia , Leptina/antagonistas & inibidores , Receptores para Leptina/antagonistas & inibidores , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/tratamento farmacológico , Animais , Anorexia/sangue , Anorexia/tratamento farmacológico , Anorexia/etiologia , Caquexia/sangue , Metabolismo Energético/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Leptina/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/fisiopatologia , Insuficiência Renal Crônica/sangue , Transdução de Sinais/efeitos dos fármacos , Redução de Peso/efeitos dos fármacos
6.
Kidney Dis (Basel) ; 10(4): 313-326, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39131880

RESUMO

Background: Primary hyperoxaluria (PH) is a rare autosomal recessive disorder, mainly due to the increase in endogenous oxalate production, causing a series of clinical features such as kidney stones, nephrocalcinosis, progressive impairment of renal function, and systemic oxalosis. There are three common genetic causes of glycolate metabolism anomalies. Among them, PH type 1 is the most prevalent and severe type, and early end-stage renal failure often occurs. Summary: This review summarizes PH through pathophysiology, genotype, clinical manifestation, diagnosis, and treatment options. And explore the characteristics of Chinese PH patients. Key Messages: Diagnosis of this rare disease is based on clinical symptoms, urinary or blood oxalate concentrations, liver biopsy, and genetic testing. Currently, the main treatment is massive hydration, citrate inhibition of crystallization, dialysis, liver and kidney transplantation, and pyridoxine. Recently, RNA interference drugs have also been used. In addition, technologies such as gene editing and autologous liver cell transplantation are also being developed. C.815_816insGA and c.33_34insC mutation in the AGXT gene could be a common variant in Chinese PH1 population. Mutations at the end of exon 6 account for approximately 50% of all Chinese HOGA1 mutations. Currently, the treatment of PH in China still relies mainly on symptomatic and high-throughput dialysis, with poor prognosis (especially for PH1 patients).

7.
Artigo em Inglês | MEDLINE | ID: mdl-39210624

RESUMO

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.

9.
Antioxidants (Basel) ; 12(4)2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37107320

RESUMO

Redox signaling alterations contribute to chronic kidney disease (CKD)-associated cachexia. This review aims to summarize studies about redox pathophysiology in CKD-associated cachexia and muscle wasting and to discuss potential therapeutic approaches based on antioxidant and anti-inflammatory molecules to restore redox homeostasis. Enzymatic and non-enzymatic systems of antioxidant molecules have been studied in experimental models of kidney diseases and patients with CKD. Oxidative stress is increased by several factors present in CKD, including uremic toxins, inflammation, and metabolic and hormone alterations, leading to muscle wasting. Rehabilitative nutritional and physical exercises have shown beneficial effects for CKD-associated cachexia. Anti-inflammatory molecules have also been tested in experimental models of CKD. The importance of oxidative stress has been shown by experimental studies in which antioxidant therapies ameliorated CKD and its associated complications in the 5/6 nephrectomy model. Treatment of CKD-associated cachexia is a challenge and further studies are necessary to investigate potential therapies involving antioxidant therapy.

10.
Am J Physiol Renal Physiol ; 303(9): F1315-24, 2012 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-22914778

RESUMO

Aberrant melanocortin signaling has been implicated in the pathogenesis of wasting in chronic kidney disease (CKD). Previously, we demonstrated that agouti-related peptide (AgRP), a melenocortin-4 receptor antagonist, reduced CKD-associated cachexia in CKD mice. Our previous studies with AgRP utilized dual energy X-ray (DXA) densitometry to assess the body composition in mice (Cheung W, Kuo HJ, Markison S, Chen C, Foster AC, Marks DL, Mak RH. J Am Soc Nephrol 18: 2517-2524, 2007; Cheung W, Yu PX, Little BM, Cone RD, Marks DL, Mak RH. J Clin Invest 115: 1659-1665, 2005). DXA is unable to differentiate water content in mice, and fluid retention in CKD may lead to an overestimate of lean mass. In this study, we employed quantitative magnetic resonance technique to evaluate body composition change following central administration of AgRP in a CKD mouse model. AgRP treatment improved energy expenditure, total body mass, fat mass, and lean body mass in CKD mouse. We also investigated the effect of CKD-associated cachexia on the signaling pathways leading to wasting in skeletal muscle, as well as whether these changes can be ameliorated by central administration of AgRP. AgRP treatment caused an overall decrease in proinflammatory cytokines, which may be one important mechanism of its effects. Muscle wasting in CKD may be due to the activation of proteolytic pathways as well as inhibition of myogenesis and muscle regeneration processes. Our results suggest that these aberrant pathological pathways leading to muscle wasting in CKD mice were ameliorated by central administration of AgRP.


Assuntos
Proteína Relacionada com Agouti/farmacologia , Caquexia/prevenção & controle , Inflamação/prevenção & controle , Melanocortinas/antagonistas & inibidores , Debilidade Muscular/prevenção & controle , Insuficiência Renal Crônica/complicações , Animais , Composição Corporal/efeitos dos fármacos , Composição Corporal/fisiologia , Caquexia/etiologia , Caquexia/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Inflamação/etiologia , Inflamação/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Debilidade Muscular/metabolismo , Nefrectomia/efeitos adversos , Receptor Tipo 4 de Melanocortina/antagonistas & inibidores , Insuficiência Renal Crônica/etiologia , Insuficiência Renal Crônica/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia
11.
Kidney Int ; 82(4): 373-4, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22846810

RESUMO

Multiple microRNAs (miRs) are implicated in muscle cell differentiation and muscle mass regulation. Pharmacological agents targeting miR-486 and other miRs, involved in muscle mass regulation, could potentially be developed into therapeutic agents for muscle wasting. Muscle wasting is prevalent among patients with chronic kidney disease (CKD). Xu et al. showed that miR-486 mimetic ameliorated muscle wasting in mice with CKD. miR mimetics may represent a new therapeutic frontier for muscle wasting in CKD.


Assuntos
Fatores de Transcrição Forkhead/metabolismo , MicroRNAs/metabolismo , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Atrofia Muscular/etiologia , Insuficiência Renal Crônica/complicações , Animais , Proteína Forkhead Box O1 , Masculino
12.
Pediatr Nephrol ; 27(2): 173-81, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21298504

RESUMO

Children with chronic kidney disease (CKD) are at risk for "cachexia" or "protein-energy wasting" (PEW). These terms describe a pathophysiologic process resulting in the loss of muscle, with or without loss of fat, and involving maladaptive responses, including anorexia and elevated metabolic rate. PEW has been defined specifically in relation to CKD. We review the diagnostic criteria for cachexia and PEW in CKD and consider the limitations and applicability of these criteria to children with CKD. In addition, we present an overview of the manifestations and mechanisms of cachexia and PEW. A host of pathogenetic factors are considered, including systemic inflammation, endocrine perturbations, and abnormal neuropeptide signaling, as well as poor nutritional intake. Mortality risk, which is 100- to 200-fold higher in patients with end-stage renal disease than in the general population, is strongly correlated with the components of cachexia/PEW. Further research into the causes and consequences of wasting and growth retardation is needed in order to improve the survival and quality of life for children with CKD.


Assuntos
Caquexia/etiologia , Nefropatias/complicações , Desnutrição Proteico-Calórica/etiologia , Síndrome de Emaciação/etiologia , Anorexia/etiologia , Índice de Massa Corporal , Criança , Doença Crônica , Ingestão de Energia , Metabolismo Energético , Humanos , Redução de Peso
13.
Cells ; 11(20)2022 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-36291130

RESUMO

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.


Assuntos
Caquexia , Calcitriol , Camundongos , Animais , Calcitriol/farmacologia , Calcitriol/uso terapêutico , Caquexia/metabolismo , Vitamina D/farmacologia , Vitamina D/uso terapêutico , Vitamina D/metabolismo , Atrofia Muscular/tratamento farmacológico , Atrofia Muscular/metabolismo , Músculo Esquelético/metabolismo , Camundongos Knockout , Tecido Adiposo/metabolismo , Suplementos Nutricionais
14.
Cell Mol Immunol ; 19(7): 791-804, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35545662

RESUMO

Type 2 diabetes (T2D) is highly associated with obesity. However, the factors that drive the transition from excessive weight gain to glucose metabolism disruption are still uncertain and seem to revolve around systemic immune disorder. Mucosal-associated invariant T (MAIT) cells, which are innate-like T cells that recognize bacterial metabolites, have been reported to be altered in obese people and to lead to metabolic dysfunction during obesity. By studying the immunophenotypes of blood MAIT cells from a cross-sectional cohort of obese participants with/without T2D, we found an elevation in CD27-negative (CD27-) MAIT cells producing a high level of IL-17 under T2D obese conditions, which could be positively correlated with impaired glucose metabolism in obese people. We further explored microbial translocation caused by gut barrier dysfunction in obese people as a triggering factor of MAIT cell abnormalities. Specifically, accumulation of the bacterial strain Bacteroides ovatus in the peripheral blood drove IL-17-producing CD27- MAIT cell expansion and could be associated with T2D risk in obese individuals. Overall, these results suggest that an aberrant gut microbiota-immune axis in obese people may drive or exacerbate T2D. Importantly, CD27- MAIT cell subsets and Bacteroides ovatus could represent targets for novel interventional strategies. Our findings extend current knowledge regarding the clinical relevance of body mass index (BMI)-associated variation in circulating MAIT cells to reveal the role of these cells in obesity-related T2D progression and the underlying cellular mechanisms.


Assuntos
Diabetes Mellitus Tipo 2 , Células T Invariantes Associadas à Mucosa , Bacteroides , Estudos Transversais , Glucose , Humanos , Interleucina-17 , Obesidade , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/imunologia
15.
Kidney Int ; 79(7): 697-9, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21403653

RESUMO

Ghrelin is involved in the pathogenesis of protein-energy wasting (PEW), inflammation, and cardiovascular complications in end-stage renal disease (ESRD). Plasma ghrelin may prove to be a powerful biomarker of mortality in ESRD but should be considered in the context of assay specificity, other weight-regulating hormones, nutritional status, systemic inflammation, and cardiovascular risk factors. ESRD patients with PEW, systemic inflammation, and low ghrelin and high leptin concentrations have the highest mortality risk and may benefit the most from ghrelin therapy.


Assuntos
Grelina/sangue , Falência Renal Crônica/mortalidade , Falência Renal Crônica/terapia , Diálise Renal/mortalidade , Biomarcadores/sangue , Índice de Massa Corporal , Proteína C-Reativa/análise , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/imunologia , Doenças Cardiovasculares/mortalidade , Humanos , Inflamação/sangue , Inflamação/imunologia , Inflamação/mortalidade , Falência Renal Crônica/sangue , Falência Renal Crônica/imunologia , Leptina/sangue , Desnutrição Proteico-Calórica/sangue , Desnutrição Proteico-Calórica/imunologia , Desnutrição Proteico-Calórica/mortalidade , Medição de Risco , Fatores de Risco , Fatores de Tempo
16.
Pediatr Nephrol ; 26(11): 1937-46, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21197596

RESUMO

Bone is a dynamic tissue. Skeletal bone integrity is maintained through bone modeling and remodeling. The mechanisms underlying this bone mass regulation are complex and interrelated. An imbalance in the regulation of bone remodeling through bone resorption and bone formation results in bone loss. Chronic inflammation influences bone mass regulation. Inflammation-related bone disorders share many common mechanisms of bone loss. These mechanisms are ultimately mediated through the uncoupling of bone remodeling. Cachexia, physical inactivity, pro-inflammatory cytokines, as well as iatrogenic factors related to effects of immunosuppression are some of the common mechanisms. Recently, cytokine signaling through the central nervous system has been investigated for its potential role in bone mass dysregulation in inflammatory conditions. Growing research on the molecular mechanisms involved in inflammation-induced bone loss may lead to more selective therapeutic targeting of these pathological signaling pathways.


Assuntos
Remodelação Óssea/fisiologia , Osso e Ossos/fisiopatologia , Inflamação/complicações , Transdução de Sinais/imunologia , Humanos , Inflamação/fisiopatologia
17.
Cells ; 10(12)2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34943890

RESUMO

Patients with chronic kidney disease (CKD) often have low serum concentrations of 25(OH)D3 and 1,25(OH)2D3. We investigated the differential effects of 25(OH)D3 versus 1,25(OH)2D3 repletion in mice with surgically induced CKD. Intraperitoneal supplementation of 25(OH)D3 (75 µg/kg/day) or 1,25(OH)2D3 (60 ng/kg/day) for 6 weeks normalized serum 25(OH)D3 or 1,25(OH)2D3 concentrations in CKD mice, respectively. Repletion of 25(OH)D3 normalized appetite, significantly improved weight gain, increased fat and lean mass content and in vivo muscle function, as well as attenuated elevated resting metabolic rate relative to repletion of 1,25(OH)2D3 in CKD mice. Repletion of 25(OH)D3 in CKD mice attenuated adipose tissue browning as well as ameliorated perturbations of energy homeostasis in adipose tissue and skeletal muscle, whereas repletion of 1,25(OH)2D3 did not. Significant improvement of muscle fiber size and normalization of fat infiltration of gastrocnemius was apparent with repletion of 25(OH)D3 but not with 1,25(OH)2D3 in CKD mice. This was accompanied by attenuation of the aberrant gene expression of muscle mass regulatory signaling, molecular pathways related to muscle fibrosis as well as muscle expression profile associated with skeletal muscle wasting in CKD mice. Our findings provide evidence that repletion of 25(OH)D3 exerts metabolic advantages over repletion of 1,25(OH)2D3 by attenuating adipose tissue browning and muscle wasting in CKD mice.


Assuntos
Tecido Adiposo Marrom/patologia , Caquexia/complicações , Calcifediol/farmacologia , Insuficiência Renal Crônica/complicações , Vitamina D/análogos & derivados , Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Branco/efeitos dos fármacos , Tecido Adiposo Branco/metabolismo , Animais , Caquexia/sangue , Ingestão de Energia , Metabolismo Energético/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Fibras Musculares Esqueléticas/efeitos dos fármacos , Fibras Musculares Esqueléticas/patologia , Insuficiência Renal Crônica/sangue , Transdução de Sinais/efeitos dos fármacos , Termogênese/efeitos dos fármacos , Termogênese/genética , Vitamina D/farmacologia , Síndrome de Emaciação/complicações , Aumento de Peso/efeitos dos fármacos
18.
Cells ; 10(8)2021 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-34440723

RESUMO

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.


Assuntos
Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Branco/efeitos dos fármacos , Caquexia/prevenção & controle , Cistinose/tratamento farmacológico , Antagonistas de Hormônios/farmacologia , Músculo Esquelético/efeitos dos fármacos , Atrofia Muscular/prevenção & controle , Receptores para Leptina/antagonistas & inibidores , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Marrom/patologia , Tecido Adiposo Branco/metabolismo , Tecido Adiposo Branco/patologia , Sistemas de Transporte de Aminoácidos Neutros/genética , Sistemas de Transporte de Aminoácidos Neutros/metabolismo , Animais , Composição Corporal/efeitos dos fármacos , Caquexia/etiologia , Caquexia/metabolismo , Caquexia/patologia , Cistinose/complicações , Cistinose/metabolismo , Cistinose/patologia , Modelos Animais de Doenças , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Atrofia Muscular/etiologia , Atrofia Muscular/metabolismo , Atrofia Muscular/patologia , Receptores para Leptina/metabolismo , Transdução de Sinais
19.
J Cachexia Sarcopenia Muscle ; 12(5): 1296-1311, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34196133

RESUMO

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-/- Il1ß-/- 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-1ß was significantly elevated in Ctns-/- mice relative to wild-type control mice. Cachexia was completely normalized in Ctns-/- Il1ß-/- 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.


Assuntos
Cistinose , Atrofia Muscular , Animais , Caquexia/tratamento farmacológico , Caquexia/etiologia , Caquexia/patologia , Cistinose/patologia , Humanos , Camundongos , Músculo Esquelético/patologia , Atrofia Muscular/patologia
20.
Sci Rep ; 11(1): 15141, 2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-34302016

RESUMO

Cytokines such as IL-6, TNF-α and IL-1ß 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 Il1ß-/-/CKD, Il6-/-/CKD and Tnfα-/-/CKD mice and compared with wild type (WT)/CKD controls. Parameters of cachexia phenotype were completely normalized in Il1ß-/-/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-1ß 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.


Assuntos
Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/metabolismo , Caquexia/metabolismo , Insuficiência Renal Crônica/metabolismo , Animais , Modelos Animais de Doenças , Interleucina-1beta/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Músculo Esquelético/metabolismo , Atrofia Muscular/metabolismo , Receptores de Interleucina-1/metabolismo , Transdução de Sinais/fisiologia
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