A retrospective view of the relationship of soluble Fas with anemia and outcomes in chronic kidney disease.

BACKGROUND: Anemia is common in chronic kidney disease (CKD) and is associated with outcomes. In addition, serum soluble Fas (sFas) levels are related to anemia and erythropoietin (EPO) resistance. OBJECTIVES: Firstly, to compare clinical data and serum levels of sFas, EPO, and pro-inflammatory markers between patients with non-dialytic CKD (NDD-CKD) and healthy subjects. Subsequently, to compare and evaluate the relationship of serum EPO, sFas levels with anemia, and outcomes in patients with NDD-CKD over a long follow-up period. METHODS: We performed a retrospective study in 58 NDD-CKD patients compared with 20 healthy subjects on complete blood count, kidney function, serum EPO, sFas, and inflammatory markers (CRP, IL- 6, and IFN-γ) at baseline. We then compared the same baseline data between patients with NDD-CKD who evolved to anemia and those who did not have anemia over the follow-up. We also evaluated the frequency of outcomes in patients with CKD with higher sFas levels. Finally, we performed a multivariate analysis of factors associated with CKD anemia. RESULTS: There were lower eGFR and Hb but higher serum inflammatory markers, sFas levels, sFas/eGFR, and EPO/Hb ratios in patients with NDD-CKD. Comparatively, on the other hand, NDD-CKD patients with anemia had lower eGFR but were older, had more diabetes, and had higher sFas/ eGFR, EPO/Hb ratios, and serum levels of IL-6 and sFas than NDD-CKD without anemia for an extended period. In addition, there was an association in a multivariate analysis of diabetes, age, and sFas levels with kidney anemia. Furthermore, there were higher frequencies of outcomes in increased serum sFas levels. CONCLUSION: As an elective risk factor, serum sFas levels, in addition to age and diabetes, were independently associated with kidney anemia for an extended period. Thus, more studies are necessary to analyze the proper relationship of sFas with kidney anemia and its outcomes and therapy in CKD.

P2X7 receptor-nitric oxide interaction mediates apoptosis in mouse immortalized mesangial cells exposed to high glucose / A interação do receptor P2X7 com o óxido nítrico medeia a apoptose em células mesangiais imortalizadas de camundongos expostas a níveis elevados de glicose

Abstract Introduction: Diabetes mellitus (DM) is a chronic disease characterized by hyperglycemia that leads to diabetic nephropathy (DN). We showed that P2X7, a purinergic receptor, was highly expressed in DM; however, when oxidative stress was controlled, renal NO recovered, and the activation of this receptor remained significantly reduced. The aim of this study was to assess the influence of NO on the P2X7 and apoptosis in mouse immortalized mesangial cells (MiMC) cultured in high glucose (HG) medium. Methods: MiMCs were cultured with DMEM and exposed to normal glucose (NG), mannitol (MA), or HG. Cell viability was assessed by an automated counter. Supernatants were collected for NO quantification, and proteins were extracted for analysis of NO synthases (iNOS and eNOS), caspase-3, and P2X7. Results: Cell viability remained above 90% in all groups. There was a significant increase in the proliferation of cells in HG compared to MA and NG. NO, iNOS, caspase-3, and P2X7 were significantly increased in HG compared to NG and MA, with no changes in eNOS. We observed that there was a strong and significant correlation between P2X7 and NO. Discussion: The main finding was that the production of NO by iNOS was positively correlated with the increase of P2X7 in MCs under HG conditions, showing that there is a common stimulus between them and that NO interacts with the P2X7 pathway, contributing to apoptosis in experimental DM. These findings could be relevant to studies of therapeutic targets for the prevention and/or treatment of hyperglycemia-induced kidney damage to delay DN progression.

Resumo Introdução: Diabetes mellitus (DM) é uma doença crônica caracterizada por hiperglicemia levando à nefropatia diabética (ND). Mostramos que P2X7, um receptor purinérgico, foi altamente expresso na DM; entretanto, quando o estresse oxidativo foi controlado, o NO renal recuperou-se, e a ativação deste receptor permaneceu significativamente reduzida. Este estudo objetivou avaliar a influência do NO no P2X7 e a apoptose em células mesangiais imortalizadas de camundongos (CMiC) cultivadas em meio de glicose elevada (GE). Métodos: CMiCs foram cultivadas em meio DMEM e expostas à glicose normal (GN), manitol (MA), ou GE. A viabilidade celular foi avaliada por contador automático. Sobrenadantes foram coletados para quantificação de NO, e foram extraídas proteínas para análise de NO sintases (iNOS e eNOS), caspase-3, e P2X7. Resultados: A viabilidade celular permaneceu acima de 90% em todos os grupos. Houve aumento significativo na proliferação de células na GE comparado com MA e GN. NO, iNOS, caspase-3 e P2X7 foram significativamente aumentados na GE comparados com GN e MA, sem alterações na eNOS. Observamos que houve correlação forte e significativa entre P2X7 e NO. Discussão: O principal achado foi que a produção de NO pela iNOS foi positivamente correlacionada com aumento de P2X7 em CMs sob condições de GE, mostrando que existe um estímulo comum entre eles e que o NO interage com a via do P2X7, contribuindo para apoptose na DM experimental. Estes achados podem ser relevantes para estudos de alvos terapêuticos para a prevenção e/ou tratamento de danos renais induzidos por hiperglicemia para retardar a progressão da ND.

Relation between red blood cell distribution width and acute kidney injury in patients with sepsis.

OBJECTIVE: The objective of the present study is to evaluate the association of red blood cell distribution width with acute kidney injury in sepsis. METHODS: This is a retrospective study of 849 critically ill patients with sepsis in intensive care unit. Demographic data, renal function, inflammation, complete blood count, and acid-base parameters were compared between acute kidney injury and non-acute kidney injury groups. Therefore, a multivariate analysis was performed to observe independent predictive factors. RESULTS: Comparatively, higher levels of C-reactive protein, lactate, red blood cell distribution width, and Simplified Acute Physiology Score 3 were found in the acute kidney injury group. The study showed a higher frequency of women, hemoglobin (Hgb) concentration, platelets, bicarbonate and PaO2/FiO2 ratio in the non-acute kidney injury group. In addition, there was an independent association of comorbidity-chronic kidney disease [OR 3.549, 95%CI: 1.627-7.743; p<0.001], urea [OR 1.047, 95%CI: 1.036-1.058; p<0.001] and RDW [OR 1.158, 95%CI: 1.045-1.283; p=0.005] with acute kidney injury in sepsis patients. CONCLUSION: As an elective risk factor, red blood cell distribution width was independently associated with sepsis-related acute kidney injury. Thus, red blood cell distribution width acts like a predictive factor for sepsis-induced acute kidney injury in intensive care unit admission.

P2X7 receptor-nitric oxide interaction mediates apoptosis in mouse immortalized mesangial cells exposed to high glucose.

INTRODUCTION: Diabetes mellitus (DM) is a chronic disease characterized by hyperglycemia that leads to diabetic nephropathy (DN). We showed that P2X7, a purinergic receptor, was highly expressed in DM; however, when oxidative stress was controlled, renal NO recovered, and the activation of this receptor remained significantly reduced. The aim of this study was to assess the influence of NO on the P2X7 and apoptosis in mouse immortalized mesangial cells (MiMC) cultured in high glucose (HG) medium. METHODS: MiMCs were cultured with DMEM and exposed to normal glucose (NG), mannitol (MA), or HG. Cell viability was assessed by an automated counter. Supernatants were collected for NO quantification, and proteins were extracted for analysis of NO synthases (iNOS and eNOS), caspase-3, and P2X7. RESULTS: Cell viability remained above 90% in all groups. There was a significant increase in the proliferation of cells in HG compared to MA and NG. NO, iNOS, caspase-3, and P2X7 were significantly increased in HG compared to NG and MA, with no changes in eNOS. We observed that there was a strong and significant correlation between P2X7 and NO. DISCUSSION: The main finding was that the production of NO by iNOS was positively correlated with the increase of P2X7 in MCs under HG conditions, showing that there is a common stimulus between them and that NO interacts with the P2X7 pathway, contributing to apoptosis in experimental DM. These findings could be relevant to studies of therapeutic targets for the prevention and/or treatment of hyperglycemia-induced kidney damage to delay DN progression.

Relation between red blood cell distribution width and acute kidney injury in patients with sepsis

ABSTRACT Objective The objective of the present study is to evaluate the association of red blood cell distribution width with acute kidney injury in sepsis. Methods This is a retrospective study of 849 critically ill patients with sepsis in intensive care unit. Demographic data, renal function, inflammation, complete blood count, and acid-base parameters were compared between acute kidney injury and non-acute kidney injury groups. Therefore, a multivariate analysis was performed to observe independent predictive factors. Results Comparatively, higher levels of C-reactive protein, lactate, red blood cell distribution width, and Simplified Acute Physiology Score 3 were found in the acute kidney injury group. The study showed a higher frequency of women, hemoglobin (Hgb) concentration, platelets, bicarbonate and PaO2/FiO2 ratio in the non-acute kidney injury group. In addition, there was an independent association of comorbidity-chronic kidney disease [OR 3.549, 95%CI: 1.627-7.743; p<0.001], urea [OR 1.047, 95%CI: 1.036-1.058; p<0.001] and RDW [OR 1.158, 95%CI: 1.045-1.283; p=0.005] with acute kidney injury in sepsis patients. Conclusion As an elective risk factor, red blood cell distribution width was independently associated with sepsis-related acute kidney injury. Thus, red blood cell distribution width acts like a predictive factor for sepsis-induced acute kidney injury in intensive care unit admission.

Nitric oxide (NO) is associated with gentamicin (GENTA) nephrotoxicity and the renal function recovery after suspension of GENTA treatment in rats.

GENTA nephrotoxicity is likely to be caused, among other factors, by an increase of vasoconstrictors or a decrease of vasodilators such as NO. Few days after discontinuing GENTA treatment, the renal function is recovered, but if risk factors like advanced age, previous renal dysfunction, simultaneous use of other nephrotoxic drugs or dehydration are present, severe and progressive renal disease occurs. The aim of this study was to evaluate the renal function in rats during GENTA treatment and after its suspension as well as its relationship with NO. Rats were treated with water (vehicle, CTL) or GENTA (100 mg/kg BW) intraperitonially during 10 days; both n=24. Twelve animals of each group were sacrificed after blood and 24 h urine were collected, and their kidneys were removed for histology. In another rats this procedure underwent after 20 or 30 days of GENTA suspension. GENTA treated group developed a marked decrease in renal function, characterized by an increased serum urea and decreased creatinine clearance; NO was increased in the serum and decreased in the urine; all P < 0.01 vs CTL. Acute tubular necrosis was confirmed in GENTA treated group. After GENTA suspension we observed a normalization of urea, creatinine clearance and serum and urinary NO; the histological lesions were also attenuated. We suggest that NO could play a role in GENTA induced nephrotoxicity and recovery. The understanding of this physiopathology could be an useful tool to prevent or blunt the nephrotoxicity progression, mainly when risk factors are present.