RESUMO
An arteriovenous fistula (AVF) is the preferred vascular access for hemodialysis in uremic patients, yet its dysfunction poses a significant clinical challenge. Venous stenosis, primarily caused by venous neointimal hyperplasia, is a key factor in the failure of vascular access. During vascular access dysfunction, endothelial cells (ECs) transform mechanical stimuli into intracellular signals and interact with vascular smooth muscle cells. Tanshinone IIA, an important compound derived from Salvia miltiorrhiza, has been widely used to treat cardiovascular diseases. However, its role in modulating ECs under uremic conditions remains incompletely understood. In this research, ECs were exposed to sodium tanshinone IIA sulfonate (STS) and subjected to shear stress and uremic conditions. The results indicate that STS can reduce the suppressive effects on the expression of NF-κB p65, JNK and Collagen I in uremia-induced ECs. Moreover, the downregulation of NF-κB p65, JNK and Collagen I can be enhanced through the inhibition of ERK1/2 and the upregulation of Caveolin-1. These findings suggest that tanshinone IIA may improve EC function under uremic conditions by targeting the Caveolin-1/ERK1/2 pathway, presenting tanshinone IIA as a potential therapeutic agent against AVF immaturity caused by EC dysfunction.
Assuntos
Abietanos , Caveolina 1 , Uremia , Uremia/metabolismo , Uremia/tratamento farmacológico , Uremia/patologia , Humanos , Abietanos/farmacologia , Abietanos/uso terapêutico , Caveolina 1/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Colágeno Tipo I/metabolismo , Fator de Transcrição RelA/metabolismo , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , FenantrenosRESUMO
Chronic kidney disease (CKD) causes accumulation of uremic metabolites that negatively affect skeletal muscle. Tryptophan-derived uremic metabolites are agonists of the aryl hydrocarbon receptor (AHR), which has been shown to be activated in CKD. This study investigated the role of the AHR in skeletal muscle pathology of CKD. Compared with controls with normal kidney function, AHR-dependent gene expression (CYP1A1 and CYP1B1) was significantly upregulated in skeletal muscle of patients with CKD, and the magnitude of AHR activation was inversely correlated with mitochondrial respiration. In mice with CKD, muscle mitochondrial oxidative phosphorylation (OXPHOS) was markedly impaired and strongly correlated with the serum level of tryptophan-derived uremic metabolites and AHR activation. Muscle-specific deletion of the AHR substantially improved mitochondrial OXPHOS in male mice with the greatest uremic toxicity (CKD + probenecid) and abolished the relationship between uremic metabolites and OXPHOS. The uremic metabolite/AHR/mitochondrial axis in skeletal muscle was verified using muscle-specific AHR knockdown in C57BL/6J mice harboring a high-affinity AHR allele, as well as ectopic viral expression of constitutively active mutant AHR in mice with normal renal function. Notably, OXPHOS changes in AHRmKO mice were present only when mitochondria were fueled by carbohydrates. Further analyses revealed that AHR activation in mice led to significantly increased pyruvate dehydrogenase kinase 4 (Pdk4) expression and phosphorylation of pyruvate dehydrogenase enzyme. These findings establish a uremic metabolite/AHR/Pdk4 axis in skeletal muscle that governs mitochondrial deficits in carbohydrate oxidation during CKD.
Assuntos
Camundongos Endogâmicos C57BL , Músculo Esquelético , Fosforilação Oxidativa , Piruvato Desidrogenase Quinase de Transferência de Acetil , Receptores de Hidrocarboneto Arílico , Insuficiência Renal Crônica , Triptofano , Animais , Receptores de Hidrocarboneto Arílico/metabolismo , Receptores de Hidrocarboneto Arílico/genética , Camundongos , Masculino , Insuficiência Renal Crônica/metabolismo , Triptofano/metabolismo , Músculo Esquelético/metabolismo , Humanos , Piruvato Desidrogenase Quinase de Transferência de Acetil/metabolismo , Piruvato Desidrogenase Quinase de Transferência de Acetil/genética , Uremia/metabolismo , Mitocôndrias Musculares/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Feminino , Camundongos Knockout , Citocromo P-450 CYP1B1/metabolismo , Citocromo P-450 CYP1B1/genética , Citocromo P-450 CYP1A1/metabolismo , Citocromo P-450 CYP1A1/genética , Pessoa de Meia-Idade , Metabolismo Energético , Modelos Animais de DoençasRESUMO
Acute kidney injury (AKI) is often accompanied by uremic encephalopathy resulting from accumulation of uremic toxins in brain possibly due to impaired blood-brain barrier (BBB) function. Anionic uremic toxins are substrates or inhibitors of organic anionic transporters (OATs). In this study we investigated the CNS behaviors and expression/function of BBB OAT3 in AKI rats and mice, which received intraperitoneal injection of cisplatin 8 and 20 mg/kg, respectively. We showed that cisplatin treatment significantly inhibited the expressions of OAT3, synaptophysin and microtubule-associated protein 2 (MAP2), impaired locomotor and exploration activities, and increased accumulation of uremic toxins in the brain of AKI rats and mice. In vitro studies showed that uremic toxins neither alter OAT3 expression in human cerebral microvascular endothelial cells, nor synaptophysin and MAP2 expressions in human neuroblastoma (SH-SY5Y) cells. In contrast, tumour necrosis factor alpha (TNFα) and the conditioned medium (CM) from RAW264.7 cells treated with indoxyl sulfate (IS) significantly impaired OAT3 expression. TNFα and CM from IS-treated BV-2 cells also inhibited synaptophysin and MAP2 expressions in SH-SY5Y cells. The alterations caused by TNFα and CMs in vitro, and by AKI and TNFα in vivo were abolished by infliximab, a monoclonal antibody designed to intercept and neutralize TNFα, suggesting that AKI impaired the expressions of OAT3, synaptophysin and MAP2 in the brain via IS-induced TNFα release from macrophages or microglia (termed as IS-TNFα axis). Treatment of mice with TNFα (0.5 mg·kg-1·d-1, i.p. for 3 days) significantly increased p-p65 expression and reduced the expressions of Nrf2 and HO-1. Inhibiting NF-κB pathway, silencing p65, or activating Nrf2 and HO-1 obviously attenuated TNFα-induced downregulation of OAT3, synaptophysin and MAP2 expressions. Significantly increased p-p65 and decreased Nrf2 and HO-1 protein levels were also detected in brain of AKI mice and rats. We conclude that AKI inhibits the expressions of OAT3, synaptophysin and MAP2 due to IS-induced TNFα release from macrophages or microglia. TNFα impairs the expressions of OAT3, synaptophysin and MAP2 partly via activating NF-κB pathway and inhibiting Nrf2-HO-1 pathway.
Assuntos
Injúria Renal Aguda , Cisplatino , Indicã , Fator de Necrose Tumoral alfa , Animais , Injúria Renal Aguda/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Humanos , Camundongos , Masculino , Células RAW 264.7 , Ratos , Camundongos Endogâmicos C57BL , Transportadores de Ânions Orgânicos Sódio-Independentes/metabolismo , Ratos Sprague-Dawley , Sinaptofisina/metabolismo , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/efeitos dos fármacos , Uremia/metabolismo , Uremia/complicações , Linhagem Celular TumoralRESUMO
BACKGROUND AND HYPOTHESIS: Pruritus is a common and distressing symptom that affects patients with chronic kidney disease. The concentration of protein bounded uremic toxin was associated with the uremic pruritus. The aim is to assess the efficacy of AST-120 for uremic pruritus in hemodialysis patients. MATERIALS AND METHODS: The participants were enrolled and then divided into the AST-120 treatment group and control group with a ratio of 2:1. All participants underwent pre-observation screenings two weeks before the study with three visits. In the treatment phase (week 1 to week 4), the treatment group added 6g/day of AST-120 along with routine anti-pruritic treatment. Visual analog scale (VAS) and biochemical parameters were measured. RESULTS: The VAS score began to be lower in the AST-120 treatment group after the 5th visiting (p < 0.05). The reduction in indoxyl sulfate (IS) at 5th week along with TNF-alpha. The reduction ratio of indoxyl sulfate correlated with reduction of parathyroid hormone. CONCLUSION: This study has demonstrated that the four-week treatment of AST-120 decreased the severity of uremic pruritus in patients with ESRD. The concentration of IS and TNF-alpha decreased in the AST-120 treatment group. The reduction of iPTH correlated with the reduction of IS in the AST-120 treatment.
Assuntos
Carbono , Indicã , Óxidos , Uremia , Humanos , Uremia/complicações , Uremia/metabolismo , Citocinas , Fator de Necrose Tumoral alfa , Diálise Renal/efeitos adversos , Prurido/tratamento farmacológico , Prurido/etiologiaRESUMO
BACKGROUND/AIM: Uremic cardiomyopathy (UCM) is a characteristic cardiac pathology that is commonly found in patients with chronic kidney disease. This study dissected the mechanism of SPI1 in myocardial fibrosis and inflammation induced by UCM through S100A8/A9. METHODS: An UCM rat model was established, followed by qRT-PCR and western blot analyses of SPI1 and S100A8/A9 expression in myocardial tissues. After alterations of SPI1 and S100A8/A9 expression in UCM rats, the blood specimens were harvested from the cardiac apex of rats. The levels of creatine phosphokinase-MB (CK-MB), blood creatinine, blood urea nitrogen (BUN), and inflammatory cytokines (interleukin [IL]-6, IL-1ß, and tumor necrosis factor-α [TNF-α]) were examined in the collected blood. Collagen fibrosis was assessed by Masson staining. The expression of fibrosis markers [transforming growth factor (TGF)-ß1, α-smooth muscle actin (SMA), Collagen 4a1, and Fibronectin], IL-6, IL-1ß, and TNF-α was measured in myocardial tissues. Chromatin immunoprecipitation and dual-luciferase reporter gene assays were conducted to test the binding relationship between SPI1 and S100A8/A9. RESULTS: S100A8/A9 and SPI1 were highly expressed in the myocardial tissues of UCM rats. Mechanistically, SPI1 bound to the promoter of S100A8/A9 to facilitate S100A8/A9 transcription. S100A8/A9 or SPI1 knockdown reduced myocardial fibrosis and inflammation and the levels of CK-MB, blood creatinine, and BUN, as well as the expression of TGF-ß1, α-SMA, Collagen 4a1, Fibronectin, IL-6, TNF-α, and IL-1ß in UCM rats. CONCLUSION: SPI1 knockdown diminished S100A8/A9 transcription, thus suppressing myocardial fibrosis and inflammation caused by UCM.
Assuntos
Calgranulina A , Calgranulina B , Cardiomiopatias , Animais , Ratos , Actinas/metabolismo , Calgranulina A/genética , Calgranulina A/metabolismo , Calgranulina B/genética , Calgranulina B/metabolismo , Cardiomiopatias/genética , Cardiomiopatias/metabolismo , Cardiomiopatias/patologia , Cardiomiopatias/prevenção & controle , Creatina Quinase , Creatinina , Citocinas/metabolismo , Regulação para Baixo , Fibronectinas/metabolismo , Fibrose/genética , Fibrose/metabolismo , Ilhas Genômicas , Inflamação/genética , Inflamação/metabolismo , Interleucina-6/metabolismo , Luciferases/genética , Luciferases/metabolismo , Proteína SUMO-1/genética , Proteína SUMO-1/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Fatores de Crescimento Transformadores/genética , Fatores de Crescimento Transformadores/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Uremia/complicações , Uremia/genética , Uremia/metabolismoRESUMO
Oxidative stress (OS) is essential in uremia-associated comorbidities, including renal anemia. Complications experienced by hemodialysis (HD) patients, such as hypoxemia and uremic toxins accumulation, induce OS and premature death of red blood cells (RBC). We aimed to characterize reactive oxygen species (ROS) production and antioxidant pathways in HD-RBC and RBC from healthy controls (CON-RBC) and evaluate the role of uremia and hypoxia in these pathways. ROS production, xanthine oxidase (XO) and superoxide dismutase (SOD) activities, glutathione (GSH), and heme oxygenase-1 (HO-1) levels were measured using flow cytometry or spectrophotometry in CON-RBC and HD-RBC (pre- and post-HD), at baseline and after 24 h incubation with uremic serum (S-HD) and/or under hypoxic conditions (5% O2 ). Ketoprofen was used to inhibit RBC uremic toxins uptake. HD-RBC showed higher ROS levels and lower XO activity than CON-RBC, particularly post-HD. GSH levels were lower, while SOD activity and HO-1 levels of HD-RBC were higher than control. Hypoxia per se triggered ROS production in CON-RBC and HD-RBC. S-HD, on top of hypoxia, increased ROS levels. Inhibition of uremic toxins uptake attenuated ROS of CON and HD-RBC under hypoxia and uremia. CON-RBC in uremia and hypoxia showed lower GSH levels than cells in normoxia and non-uremic conditions. Redox mechanisms of HD-RBC are altered and prone to oxidation. Uremic toxins and hypoxia play a role in unbalancing these systems. Hypoxia and uremia participate in the pathogenesis of OS in HD-RBC and might induce RBC death and thus compound anemia.
Assuntos
Anemia , Uremia , Humanos , Eritrócitos/metabolismo , Uremia/metabolismo , Diálise Renal , Estresse Oxidativo , Glutationa/metabolismo , Hipóxia/metabolismo , Anemia/metabolismoRESUMO
Acetaminophen (APAP) is commonly prescribed as an antipyretic and analgesic agent in the practical field. Like every other drug(s), APAP also undergo metabolism by oxidation or conjugation by glucuronate and sulphate to form the toxic metabolite N-acetyl-p-benzoquinone imine (NAPQI). Moreover, the NAPQI is detoxified by conjugation with reduced glutathione (GSH). Interestingly, APAP is also metabolized in the kidney by deacetylation reaction in the presence of N-deacetylase enzyme into another severely toxic but minor metabolite, p-aminophenol. Both NAPQI and p-aminophenol shows nephrotoxicity as well as hepatotoxicity. Hence, the long-term therapeutic dose use and unnecessary overdose of APAP are of great concern as prolonged negligence may cost the nephrotoxicity that may lead to uremia and finally to kidney failure. It has recently been investigated that probiotic supplementation inhibits the sequential events associated with APAP-induced nephrotoxicity. This review emphasizes the role of different probiotics that have already been investigated in nephrotoxicity or uremia caused by APAP overdose.
Assuntos
Probióticos , Insuficiência Renal , Uremia , Acetaminofen/efeitos adversos , Glutationa/metabolismo , Humanos , Probióticos/uso terapêutico , Uremia/metabolismoRESUMO
INTRODUCTION: Uremia could accelerate atherosclerosis (AS) formation involving Treg/Th17 imbalance. Losartan regulates the imbalance between regulatory T cells (Treg cells) and T helper 17 cells (Th17 cells). However, their interactions in uremia accelerated AS (UAAS) remained poorly understood. METHODS: UAAS mice model was established, and after losartan and VO-OHpic (VO, phosphatase and tensin homolog [PTEN] inhibitor) injection, biological indexes, and inflammatory cytokines (transforming growth factor-ß1, TGF-ß1; interleukin-10 [IL-10]; IL-17 and IL-6) levels were determined using enzyme-linked immunosorbent assay. Pathological changes on aorta were observed using hematoxylin-eosin staining. Percentages of Treg cells (CD4+CD25+Foxp3+) and Th17 cells (CD4+IL-17+) in total CD4+ T cells were determined using flow cytometry. PTEN expressions were measured using Western blot, quantitative real-time polymerase chain reaction, and immunohistochemistry staining as needed. RESULTS: After UAAS mice model construction, biological indexes (urea, cholesterol, and triglycerides) levels were increased, and aortic atherosclerotic plaque was formed. In UAAS mice, in total CD4+ T cells, Treg cells percentage was decreased yet Th17 cells percentage was increased, and TGF-ß1 and IL-10 levels were downregulated yet IL-17 and IL-6 levels were upregulated. An opposite effect was found after losartan treatment. PTEN was downregulated in UAAS mice, and suppressing PTEN reversed the alleviating effects of losartan in UAAS mice. CONCLUSION: Losartan attenuated UAAS in mice by regulating Treg/Th17 cells balance via mediating PTEN/PI3K/Akt pathway, providing possible therapeutic method for UAAS in clinical practice.
Assuntos
Aterosclerose , Uremia , Animais , Aterosclerose/tratamento farmacológico , Aterosclerose/patologia , Modelos Animais de Doenças , Interleucina-10/metabolismo , Interleucina-10/farmacologia , Interleucina-17/metabolismo , Interleucina-17/farmacologia , Interleucina-6/metabolismo , Losartan/metabolismo , Losartan/farmacologia , Losartan/uso terapêutico , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Linfócitos T Reguladores , Células Th17/metabolismo , Células Th17/patologia , Fator de Crescimento Transformador beta1/metabolismo , Uremia/tratamento farmacológico , Uremia/metabolismoRESUMO
OBJECTIVE: Vascular calcification (VC) is an important risk factor for cardiovascular disease in maintenance hemodialysis (MHD) patients. Hyperphosphatemia and microinflammation statement are known major contributors to the development of VC; however, the mechanisms are unknown. The aims of this study were to explore the risk factors of VC in MHD patients and to explore whether high phosphate could increase the secretion of inflammatory cytokines via PiT-1 in monocytes. METHODS: A cross-sectional study was conducted on 65 MHD patients to assess the relevance of coronary artery calcification (CAC), inflammatory factors, serum phosphate, and sodium-dependent phosphate cotransporter (NPT) mRNA expression of peripheral blood mononuclear cells (PBMCs). Multivariate logistic regression analysis was used to analyze the predictors of CAC. The calcification effects of high phosphate (HP), TNF-α, and supernatants of healthy human monocytes treated with HP were further evaluated in cultured HASMCs. RESULTS: Diabetes, longer dialysis vintage, higher serum TNF-α levels, and PiT-1 mRNA expression of PBMCs) were independent risk factors of CAC in MHD patients. The mRNA levels of PiT-1 in PBMCs were positively correlated with serum phosphate, CAC scores, and Pit-2 mRNA levels of PBMCs. The expressions of TNF-α, IL-6, and PiT-1 in human monocytes were significantly increased in a dose-dependent manner after treatment with HP, which was subsequently inhibited by NPT antagonist phosphonoformic acid. Neither TNF-α alone nor supernatants of monocytes stimulated with HP promoted the expression of osteopontin and Runt-related transcription factor 2 (Runx2) or caused mineralization in human aortic smooth muscle cells, but combined with HP intervention, the calcification effects were markedly increased in human aortic smooth muscle cells and ameliorated by phosphonoformic acid treatment. CONCLUSION: Hyperphosphatemia directly increased the synthesis and secretion of TNF-α by monocytes may via PiT-1 pathway, resulting in elevated systemic inflammatory response, which may further aggravate VC induced by phosphate overload in MHD patients.
Assuntos
Hiperfosfatemia , Uremia , Calcificação Vascular , Células Cultivadas , Estudos Transversais , Feminino , Foscarnet/efeitos adversos , Foscarnet/metabolismo , Humanos , Hiperfosfatemia/complicações , Leucócitos Mononucleares/metabolismo , Masculino , Músculo Liso Vascular/metabolismo , Fosfatos/metabolismo , RNA Mensageiro/metabolismo , RNA Mensageiro/farmacologia , Proteínas Cotransportadoras de Sódio-Fosfato Tipo III/genética , Proteínas Cotransportadoras de Sódio-Fosfato Tipo III/metabolismo , Fator de Necrose Tumoral alfa/genética , Uremia/complicações , Uremia/metabolismo , Calcificação Vascular/etiologiaRESUMO
Although the cause of neurological disease in patients with chronic kidney disease (CKD) has not been completely identified yet, recent papers have identified accumulated uremic toxin as its main cause. Additionally, omega-3 polyunsaturated fatty acid (ω-3 PUFA) plays an important role in maintaining normal nerve function, but its protective effects against uremic toxin is unclear. The objective of this study was to identify brain damage caused by uremic toxicity and determine the protective effects of ω-3 PUFA against uremic toxin. We divided mice into the following groups: wild-type (wt) sham (n = 8), ω-3 PUFA sham (n = 8), Fat-1 sham (n = 8), ischemia-reperfusion (IR) (n = 20), and ω-3 PUFA+IR (n = 20) Fat-1+IR (n = 20). Brain tissue, kidney tissue, and blood were collected three days after the operation of mice (sham and IR operation). This study showed that Ki67 and neuronal nuclei (NeuN) decreased in the brain of uremic mice as compared to wt mice brain, but increased in the ω-3 PUFA-treated uremic mice and the brain of uremic Fat-1 mice as compared to the brain of uremic mice. The pro-apoptotic protein expressions were increased, whereas anti-apoptotic protein expression decreased in the brain of uremic mice as compared to wt mice brain. However, apoptotic protein expression decreased in the ω-3 PUFA-treated uremic mice and the brain of uremic Fat-1 mice as compared to the brain of uremic mice. Furthermore, the brain of ω-3 PUFA-treated uremic mice and uremic Fat-1 mice showed increased expression of p-PI3K, p-PDK1, and p-Akt as compared to the brain of uremic mice. We confirm that uremic toxin damages the brain and causes cell death. In these injuries, ω-3 PUFA plays an important role in neuroprotection through PI(3)K-Akt signaling.
Assuntos
Lesões Encefálicas , Encéfalo , Ácidos Graxos Ômega-3/farmacologia , Transdução de Sinais/efeitos dos fármacos , Uremia , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Lesões Encefálicas/tratamento farmacológico , Lesões Encefálicas/metabolismo , Lesões Encefálicas/patologia , Linhagem Celular , Rim/metabolismo , Rim/patologia , Masculino , Camundongos , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Uremia/tratamento farmacológico , Uremia/metabolismo , Uremia/patologiaRESUMO
Epithelial ovarian cancer (EOC) is a fatal gynecologic cancer, and its poor prognosis is mainly due to delayed diagnosis. Therefore, biomarker identification and prognosis prediction are crucial in EOC. Altered cell metabolism is a characteristic feature of cancers, and metabolomics reflects an individual's current phenotype. In particular, plasma metabolome analyses can be useful for biomarker identification. In this study, we analyzed 624 metabolites, including uremic toxins (UTx) in plasma derived from 80 patients with EOC using ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Compared with the healthy control, we detected 77 significantly increased metabolites and 114 significantly decreased metabolites in EOC patients. Especially, decreased concentrations of lysophosphatidylcholines and phosphatidylcholines and increased concentrations of triglycerides were observed, indicating a metabolic profile characteristic of EOC patients. After calculating the parameters of each metabolic index, we found that higher ratios of kynurenine to tryptophan correlates with worse prognosis in EOC patients. Kynurenine, one of the UTx, can affect the prognosis of EOC. Our results demonstrated that plasma metabolome analysis is useful not only for the diagnosis of EOC, but also for predicting prognosis with the variation of UTx and evaluating response to chemotherapy.
Assuntos
Biomarcadores Tumorais/sangue , Carcinoma Epitelial do Ovário/sangue , Metaboloma , Neoplasias Ovarianas/sangue , Toxinas Biológicas/sangue , Adulto , Idoso , Biomarcadores Tumorais/metabolismo , Carcinoma Epitelial do Ovário/metabolismo , Feminino , Humanos , Metabolômica , Pessoa de Meia-Idade , Neoplasias Ovarianas/metabolismo , Prognóstico , Toxinas Biológicas/metabolismo , Uremia/metabolismoRESUMO
Secondary hyperparathyroidism and abnormalities in tryptophan (TRP) metabolism are commonly observed in chronic kidney disease (CKD). The present study aimed to establish potential interactions between endogenous parathyroid hormone (PTH) and activation of the bone kynurenine (KYN) pathway in relation to bone turnover and strength in young rats after one month (CKD-1) and three months (CKD-3) of experimental CKD. TRP, KYN, KYN/TRP ratio and bone turnover markers (BTMs) were measured in trabecular and cortical bone tissue. Expression of aryl hydrocarbon receptor (AhR) and the genes involved in osteogenesis was determined in femoral bone. Biomechanical testing of femoral diaphysis and femoral neck was also performed. Activation of the KYN pathway in trabecular bone during CKD development intensified the expression of genes related to osteogenesis, which led to a decrease in cyclic adenosine monophosphate (cAMP) and BTMs levels, resulting in a stiffer and mechanically weaker femoral neck. In contrast, reduction of the KYN pathway in cortical bone allowed to unblock the PTH-dependent anabolic activating transcription factor 4/parathyroid hormone 1 receptor (PTH1R/ATF4) axis, led to cAMP accumulation, better bone turnover and strength in the course of CKD development. In summary, the paracrine KYN pathway in bone can interfere with the anabolic effects of PTH on bone through disrupting PTH-dependent molecular signaling.
Assuntos
Fêmur/metabolismo , Cinurenina/metabolismo , Comunicação Parácrina , Hormônio Paratireóideo/metabolismo , Transdução de Sinais , Uremia/metabolismo , Fator 4 Ativador da Transcrição/metabolismo , Animais , Osso Esponjoso/metabolismo , Osso Cortical/metabolismo , AMP Cíclico/metabolismo , Masculino , Ratos , Ratos Wistar , Receptor Tipo 1 de Hormônio Paratireóideo/metabolismoRESUMO
Cytokine storm is recognized as one of the factors contributing to organ failures and mortality in patients with COVID-19. Due to chronic inflammation, COVID-19 patients with diabetes mellitus (DM) or renal disease (RD) have more severe symptoms and higher mortality. However, the factors that contribute to severe outcomes of COVID-19 patients with DM and RD have received little attention. In an effort to investigate potential treatments for COVID-19, recent research has focused on the immunomodulation functions of mesenchymal stem cells (MSCs). In this study, the correlation between DM and RD and the severity of COVID-19 was examined by a combined approach with a meta-analysis and experimental research. The results of a systematic review and meta-analysis suggested that the odd of mortality in patients with both DM and RD was increased in comparison to those with a single comorbidity. In addition, in the experimental research, the data showed that high glucose and uremic toxins contributed to the induction of cytokine storm in human lung adenocarcinoma epithelial cells (Calu-3 cells) in response to SARS-CoV Peptide Pools. Of note, the incorporation of Wharton's jelly MSC-derived extracellular vesicles (WJ-EVs) into SARS-CoV peptide-induced Calu-3 resulted in a significant decrease in nuclear NF-κB p65 and the downregulation of the cytokine storm under high concentrations of glucose and uremic toxins. This clearly suggests the potential for WJ-EVs to reduce cytokine storm reactions in patients with both chronic inflammation diseases and viral infection.
Assuntos
Síndrome da Liberação de Citocina/prevenção & controle , Vesículas Extracelulares/fisiologia , Células-Tronco Mesenquimais/citologia , SARS-CoV-2/fisiologia , Geleia de Wharton/citologia , Adulto , Idoso , COVID-19/sangue , COVID-19/complicações , COVID-19/metabolismo , COVID-19/terapia , Células Cultivadas , Técnicas de Cocultura , Síndrome da Liberação de Citocina/genética , Síndrome da Liberação de Citocina/metabolismo , Síndrome da Liberação de Citocina/virologia , Citocinas/genética , Citocinas/metabolismo , Complicações do Diabetes/sangue , Complicações do Diabetes/metabolismo , Complicações do Diabetes/terapia , Complicações do Diabetes/virologia , Diabetes Mellitus/sangue , Diabetes Mellitus/metabolismo , Diabetes Mellitus/terapia , Diabetes Mellitus/virologia , Relação Dose-Resposta a Droga , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Glucose/metabolismo , Glucose/farmacologia , Humanos , Mediadores da Inflamação/metabolismo , Masculino , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/fisiologia , Gravidez , Toxinas Biológicas/metabolismo , Toxinas Biológicas/farmacologia , Cordão Umbilical/citologia , Uremia/sangue , Uremia/complicações , Uremia/metabolismo , Uremia/terapiaRESUMO
Secondary hyperparathyroidism (SHPT) in uremic patients is characterized by parathyroid gland (PTG) hyperplasia and parathyroid hormone (PTH) elevation. Previously, we demonstrated that NF-κB activation contributed to parathyroid cell proliferation in rats with chronic kidney disease. Although vitamin D inhibits inflammation and ameliorates SHPT, the contribution of vitamin D deficiency to SHPT via local NF-κB activation remains to be clarified. PTGs collected from 10 uremic patients with advanced SHPT were used to test the expressions of vitamin D receptor (VDR), NF-κB, and proliferating cell nuclear antigen (PCNA). Freshly excised PTG tissues were incubated for 24 hours in vitro with VDR activator (VDRA) calcitriol or NF-κB inhibitor pyrrolidine thiocarbamate (PDTC). Chromatin immunoprecipitation (ChIP) and luciferase reporter assays were performed to investigate the regulation of PTH transcription by NF-κB. We found higher levels of activated NF-κB and lower expression of VDR in nodular hyperplastic PTGs than in diffuse hyperplasia. In cultured PTG tissues, treatment with VDRA or PDTC inhibited NF-κB activation and PCNA expression, and downregulated preproPTH mRNA and intact PTH levels. ChIP assays demonstrated the presence of NF-κB binding sites in PTH promoter. Furthermore, in luciferase reporter assays, addition of exogenous p65 significantly increased PTH luciferase activity by 2.4-fold (P < 0.01), while mutation of NF-κB binding site at position -908 of the PTH promoter suppressed p65-induced PTH reporter activity (P < 0.01). In summary, local NF-κB activation contributes to SHPT and mediates the transcriptional activation of PTH directly in uremic patients. Vitamin D deficiency may be involved in SHPT via the activation of NF-κB pathway.
Assuntos
NF-kappa B/fisiologia , Glândulas Paratireoides/metabolismo , Hormônio Paratireóideo/metabolismo , Uremia/metabolismo , Calcitriol/administração & dosagem , Feminino , Humanos , Hiperparatireoidismo Secundário/tratamento farmacológico , Hiperparatireoidismo Secundário/metabolismo , Hiperparatireoidismo Secundário/patologia , Hiperplasia , Masculino , Pessoa de Meia-Idade , NF-kappa B/antagonistas & inibidores , Glândulas Paratireoides/química , Glândulas Paratireoides/patologia , Hormônio Paratireóideo/biossíntese , Hormônio Paratireóideo/genética , Antígeno Nuclear de Célula em Proliferação/análise , Pirrolidinas/administração & dosagem , Receptores de Calcitriol/análise , Receptores de Calcitriol/efeitos dos fármacos , Receptores de Calcitriol/metabolismo , Tiocarbamatos/administração & dosagem , Técnicas de Cultura de Tecidos , Fator de Transcrição RelA/análise , Transcrição Gênica/efeitos dos fármacos , Uremia/complicações , Uremia/patologiaRESUMO
AIM: The therapeutic expediency of cisplatin was limited due to its nephrotoxic side effects, so this study planned to assess the nephrotic and neuroprotective impact of metformin (MET) and low-dose radiation (LDR) in cisplatin-prompted kidney injury and uremic encephalopathy (UE). METHODS: The effect of the 10-day MET treatment (200 mg/kg, orally) and/or fractionated LDR (0.25 Gy, of the total dose of 0.5 Gy, 1st and 7th day, respectively) on (5 mg/kg, intraperitoneally) cisplatin as a single dose was administered at the 5th day. Serum urea, creatinine and renal kidney injury molecule-1 were measured for the assessment of kidney function. Furthermore, the antioxidant potential in the renal and brain tissues was evaluated through, malondialdehyde and reduced glutathione estimation. Moreover, renal apoptotic markers: AMP-activated protein kinase, lipocalin, B-cell lymphoma 2 associated X protein, B-cell lymphoma 2, P53 and beclin 1 were estimated. UE was evaluated through the determination of serum inflammatory markers: nuclear factor kappa B, tumor-necrosis factor-α and interleukin 1 beta likewise, the cognitive deficits were assessed via forced swimming test, gamma-aminobutyric acid, n-methyl-d-aspartate and neuronal nitric oxide synthases besides AMP-activated protein kinase, light chain 3 and caspase3 levels in rats' cerebella. KEY FINDINGS: The obtained results revealed a noticeable improvement in the previously mentioned biochemical factors and behavioral tasks that was reinforced by histopathological examination when using the present remedy. SIGNIFICANCE: metformin and low doses of radiation afforded renoprotection and neuroprotection against cisplatin-induced acute uremic encephalopathy.
Assuntos
Biomarcadores/metabolismo , Encefalopatias/prevenção & controle , Cisplatino/toxicidade , Raios gama , Metformina/farmacologia , Fármacos Neuroprotetores/farmacologia , Uremia/prevenção & controle , Animais , Antineoplásicos/toxicidade , Encefalopatias/induzido quimicamente , Encefalopatias/metabolismo , Encefalopatias/patologia , Relação Dose-Resposta à Radiação , Glutationa/metabolismo , Hipoglicemiantes/farmacologia , Masculino , NF-kappa B/metabolismo , Estresse Oxidativo , Ratos , Fator de Necrose Tumoral alfa/metabolismo , Uremia/induzido quimicamente , Uremia/metabolismo , Uremia/patologiaRESUMO
BACKGROUND: Uremia induces various pathologic changes in the endothelium. However, there is limited information about the differences of these effects in endothelial cells originating from different parts of the vascular tree. METHODS: The effect of uremic serum obtained from patients with end stage renal failure on the gene expression and secretory activity of venous endothelial cells (VEC) and aortic endothelial cells (AEC) was studied in in vitro culture. RESULTS: In VEC, the expression of genes regulating the synthesis of von Willebrand factor (vWF) was increased by 254% (p<.005), vascular endothelial growth factor (VEGF) synthesis by 150% (p<.001), tissue plasminogen activator (t-PA) synthesis by 62% (p<.005), platelet endothelial cell adhesion molecule by 89% (p<.005), and the expression of gene regulating interleukin-6 (IL-6) synthesis was reduced. In AEC, the expression of the gene regulating synthesis of IL-6 was increased by 174% (p<.001), and the expression of the other genes was reduced. The secretion of IL-6 was reduced in VEC by 38% (p<.01) and increased in AEC by 55% (p<.005). In VEC, increased synthesis of VEGF 64% (p<.001) vWF (+34%, p<.01), and t-PA (+53%, p<.002) was observed, and in AEC it was reduced. CONCLUSIONS: VEC and AEC respond in different ways after exposure to uremic serum. VEC acquires the prothrombotic phenotype, whereas in AEC the inflammatory phenotype appears.
Assuntos
Artérias/patologia , Células Endoteliais/patologia , Endotélio Vascular/citologia , Inflamação/patologia , Uremia/metabolismo , Células Cultivadas , Células Endoteliais/metabolismo , Regulação da Expressão Gênica , Humanos , Inflamação/genética , Interleucina-6/genética , Interleucina-6/metabolismo , Falência Renal Crônica/sangue , Falência Renal Crônica/complicações , Ativador de Plasminogênio Tecidual/genética , Ativador de Plasminogênio Tecidual/metabolismo , Uremia/sangue , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fator de von Willebrand/genética , Fator de von Willebrand/metabolismoRESUMO
In obesity, adipose tissue derived inflammation is associated with unfavorable metabolic consequences. Uremic inflammation is prevalent and contributes to detrimental outcomes. However, the contribution of adipose tissue inflammation in uremia has not been characterized. We studied the contribution of adipose tissue to uremic inflammation in-vitro, in-vivo and in human samples. Exposure to uremic serum resulted in activation of inflammatory pathways including NFκB and HIF1, upregulation of inflammatory cytokines/chemokines and catabolism with lipolysis, and lactate production. Also, co-culture of adipocytes with macrophages primed by uremic serum resulted in higher inflammatory cytokine expression than adipocytes exposed only to uremic serum. Adipose tissue of end stage renal disease subjects revealed increased macrophage infiltration compared to controls after BMI stratification. Similarly, mice with kidney disease recapitulated the inflammatory state observed in uremic patients and additionally demonstrated increased peripheral monocytes and inflammatory polarization of adipose tissue macrophages (ATMS). In contrast, adipose tissue in uremic IL-6 knock out mice showed reduced ATMS density compared to uremic wild-type controls. Differences in ATMS density highlight the necessary role of IL-6 in macrophage infiltration in uremia. Uremia promotes changes in adipocytes and macrophages enhancing production of inflammatory cytokines. We demonstrate an interaction between uremic activated macrophages and adipose tissue that augments inflammation in uremia.
Assuntos
Adipócitos/imunologia , Falência Renal Crônica/imunologia , Macrófagos/imunologia , Obesidade/complicações , Uremia/imunologia , Células 3T3-L1 , Adipócitos/metabolismo , Tecido Adiposo/metabolismo , Animais , Estudos de Casos e Controles , Comunicação Celular/imunologia , Células Cultivadas , Técnicas de Cocultura , Citocinas/metabolismo , Humanos , Inflamação/sangue , Inflamação/imunologia , Mediadores da Inflamação/metabolismo , Falência Renal Crônica/sangue , Falência Renal Crônica/metabolismo , Lipólise/imunologia , Macrófagos/metabolismo , Masculino , Camundongos , Obesidade/sangue , Obesidade/imunologia , Obesidade/metabolismo , Cultura Primária de Células , Células RAW 264.7 , Células THP-1 , Uremia/sangue , Uremia/metabolismoRESUMO
Chronic kidney disease (CKD) patients obtained high levels of uremic toxins progressively develop several complications including bone fractures. Protein-bound uremic toxins especially p-cresol and indoxyl sulfate are hardly eliminated due to their high molecular weight. Thus, the abnormality of bone in CKD patient could be potentially resulted from the accumulation of uremic toxins. To determine whether protein-bound uremic toxins have an impact on osteogenesis, mesenchymal stem cells were treated with either p-cresol or indoxyl sulfate under in vitro osteogenic differentiation. The effects of uremic toxins on MSC-osteoblastic differentiation were investigated by evaluation of bone phenotype. The results demonstrated that p-cresol and indoxyl sulfate down-regulated the transcriptional level of collagen type I, deceased alkaline phosphatase activity, and impaired mineralization of MSC-osteoblastic cells. Furthermore, p-cresol and indoxyl sulfate gradually increased senescence-associated beta-galactosidase positive cells while upregulated the expression of p21 which participate in senescent process. Our findings clearly revealed that the presence of uremic toxins dose-dependently influenced a gradual deterioration of osteogenesis. The effects partially mediate through the activation of senescence-associated gene lead to the impairment of osteogenesis. Therefore, the management of cellular senescence triggered by uremic toxins could be considered as an alternative therapeutic approach to prevent bone abnormality in CKD patients.
Assuntos
Distúrbio Mineral e Ósseo na Doença Renal Crônica/metabolismo , Células-Tronco Mesenquimais/patologia , Insuficiência Renal Crônica/complicações , Toxinas Biológicas/metabolismo , Uremia/metabolismo , Células Cultivadas , Senescência Celular , Distúrbio Mineral e Ósseo na Doença Renal Crônica/etiologia , Distúrbio Mineral e Ósseo na Doença Renal Crônica/urina , Cresóis/metabolismo , Cresóis/urina , Voluntários Saudáveis , Humanos , Indicã/metabolismo , Indicã/urina , Osteogênese/fisiologia , Cultura Primária de Células , Insuficiência Renal Crônica/metabolismo , Insuficiência Renal Crônica/urina , Toxinas Biológicas/urina , Uremia/etiologia , Uremia/urinaRESUMO
BACKGROUND: Hydrogen sulfide (H2S) has been shown to inhibit the atherosclerosis development and progression. It is produced by cystathionine γ-lyase (CSE) in the cardiovascular system. In our previous study, it has been shown that CSE/H2S system plays a significant role in the changes of uremic accelerated atherosclerosis (UAAS), but the mechanism is not known clearly. METHODS: In this study, we explored the antagonism of CSE/H2S system in UAAS and identified its possible signaling molecules in ApoE-/- mice with 5/6 nephrectomy and fed with atherogenic diet. Mice were divided into sham operation group (sham group), UAAS group, sodium hydrosulfide group (UAAS+NaHS group) and propargylglycine group (UAAS+PPG group). Serum creatinine, urea nitrogen, lipid levels and lesion size of atherosclerotic plaque in the aortic roots were analyzed. Meanwhile, the expression of CSE, TGF-ß and phosphorylation of Smad3 were detected. RESULTS: Compared with sham group, the aortic root of ApoE-/- mice in the UAAS group developed early atherosclerosis, the levels of total cholesterol, triglyceride, low-density lipoprotein-cholesterol, serum creatinine and urea nitrogen were also higher than that in the sham group. NaHS administration can inhibit the development of atherosclerosis, but PPG administration can accelerate the atherosclerosis development. Meanwhile, the protein expression levels of CSE and TGF-ß and phosphorylation of Smad3 significantly decreased in the UAAS mice. Treatment of UAAS mice with NaHS inhibited TGF-ß protein expression and Smad3 phosphorylation decrease, but PPG treatment had the opposite effect. CONCLUSIONS: The CSE/H2S system is of great importance for treating atherosclerosis in patients with chronic kidney disease, and it may protect the vascular from atherosclerosis through the TGF-ß/Smad pathway.
Assuntos
Aterosclerose/metabolismo , Cistationina gama-Liase/metabolismo , Sulfeto de Hidrogênio/metabolismo , Nefrectomia , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Uremia/metabolismo , Alcinos/farmacologia , Animais , Aorta/patologia , Aterosclerose/genética , Aterosclerose/patologia , Nitrogênio da Ureia Sanguínea , Colesterol/metabolismo , LDL-Colesterol/metabolismo , Creatinina/metabolismo , Cistationina gama-Liase/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Glicina/análogos & derivados , Glicina/farmacologia , Camundongos , Camundongos Knockout para ApoE , Fosforilação , Placa Aterosclerótica/patologia , Proteína Smad3/efeitos dos fármacos , Sulfetos/farmacologia , Fator de Crescimento Transformador beta/efeitos dos fármacos , Triglicerídeos/metabolismoRESUMO
Apelin peptides (APLN) serve as second substrates for angiotensin-converting enzyme 2 (ACE2) and, in contrast to angiotensin II (AngII), exert blood-pressure lowering and vasodilatation effects through binding to G-coupled APLN receptor (APLNR). ACE2-mediated cleavage of the APLN may reduce its vasodilatory effects, but decreased ACE2 may potentiate the hypotensive properties of APLN. The role of APLN in uremia is unclear. We investigated the correlations between serum-APLN, leucocytic APLNR, and ACE2 in 32 healthy controls (NP), 66 HD, and 24 CKD3-5 patients, and the impact of APLN peptides on monocytic behavior and ACE2 expression under uremic conditions in vitro. We observed that serum APLN and leucocytic APLNR or SLCO2B1 were significantly elevated in uremic patients and correlated with decreased ACE2 on uremic leucocytes. APLN-treated THP-1 monocytes revealed significantly increased APLNR and ACE2, and reduced TNFa, IL-6, and MCSF. Uremic toxins induced a dramatic increase of miR-421 followed by significant reduction of ACE2 transcripts, partially counteracted with APLN-13 and -36. APLN-36 triggered the most potent transmigration and reduction of endothelial adhesion. These results suggest that although APLN peptides may partly protect against the decay of monocytic ACE2 transcripts, uremic milieu is the most dominant modulator of local ACE2, and likely to contribute to the progression of atherosclerosis.