Klotho inversely relates with carotid intima- media thickness in atherosclerotic patients with normal renal function (eGFR ≥60 mL/min/1.73m2): a proof-of-concept study.

Introduction: Klotho protein is predominantly expressed in the kidneys and has also been detected in vascular tissue and peripheral blood circulating cells to a lesser extent. Carotid artery intima-media thickness (CIMT) burden, a marker of subclinical atherosclerosis, has been associated with reductions in circulating Klotho levels in chronic kidney disease patients, who show reduced levels of this protein at all stages of the disease. However, the contribution of serum Klotho and its expression levels in peripheral blood circulating cells and in the carotid artery wall on the CIMT in the absence of kidney impairment has not yet been evaluated. Methods: We conducted a single-center study in 35 atherosclerotic patients with preserved kidney function (eGFR≥60 mL/min/1.73m2) subjected to elective carotid surgery. Serum levels of Klotho and cytokines TNFa, IL6 and IL10 were determined by ELISA and transcripts encoding for Klotho (KL), TNF, IL6 and IL10 from vascular segments were measured by qRT-PCR. Klotho protein expression in the intima-media and adventitia areas was analyzed using immunohistochemistry. Results: APatients with higher values of CIMT showed reduced Klotho levels in serum (430.8 [357.7-592.9] vs. 667.8 [632.5-712.9] pg/mL; p<0.001), mRNA expression in blood circulating cells and carotid artery wall (2.92 [2.06-4.8] vs. 3.69 [2.42-7.13] log.a.u., p=0.015; 0.41 [0.16-0.59] vs. 0.79 [0.37-1.4] log.a.u., p=0.013, respectively) and immunoreactivity in the intimal-medial area of the carotids (4.23 [4.15-4.27] vs. 4.49 [4.28-4.63] log µm2 p=0.008). CIMT was inversely related with Klotho levels in serum (r= -0.717, p<0.001), blood mRNA expression (r=-0.426, p=0.011), and with carotid artery mRNA and immunoreactivity levels (r= -0.45, p=0.07; r= -0.455, p= 0.006, respectively). Multivariate analysis showed that serum Klotho, together with the gene expression levels of tumor necrosis factor TNFa in blood circulating cells, were independent determinants of CIMT values (adjusted R2 = 0.593, p<0.001). Discussion: The results of this study in subjects with eGFR≥60mL/min/1.73m2 show that patients with carotid artery atherosclerosis and higher values of CIMT present reduced soluble Klotho levels, as well as decreased KL mRNA expression in peripheral blood circulating cells and Klotho protein levels in the intima-media of the carotid artery wall.

Klotho expression in peripheral blood circulating cells is associated with vascular and systemic inflammation in atherosclerotic vascular disease.

Cardiovascular disease is the leading cause of death worldwide. New therapeutic strategies are aimed to modulate the athero-inflammatory process that partially orchestrates underlying vascular damage. Peripheral blood circulating cells include different immune cells with a central role in the development of the atherogenic inflammatory response. The anti-aging protein α-Klotho has been related to protective effects against CVD. KL is expressed in monocytes, macrophages, and lymphocytes where it exerts anti-inflammatory effects. In this work, we analyse the relationships of the levels of inflammatory markers with the expression of the KL gene in PBCCs and with the serum levels of soluble KL in atherosclerotic vascular disease. For this, we conducted a cross-sectional single-center case-control study including a study group of 76 CVD patients and a control group of 16 cadaveric organ donors without medical antecedent or study indicating CVD. Vascular artery fragments and whole blood and serum samples were obtained during elective or organ retrieval surgery. Serum levels of sKL, TNFα and IL10, and gene expression levels of KL, TNF, IL10, NFKB1, DNMT1, and DNMT3A in PBCCs were measured. In these cells, we also determined KL promoter methylation percentage. Histological and immunohistochemical analyses were employed to visualize atherosclerotic lesions and to measure IL10 and TNFα levels in vascular fragments. Patients with CVD presented higher values of proinflammatory markers both at systemic and in the vasculature and in the PBCCs, compared to the control group. In PBCCs, CVD patients also presented lower gene expression levels of KL gene (56.4% difference, P < 0.001), higher gene expression levels of DNMT1 and DNMT3A (P < 0.0001, for both) and a higher methylation status of in the promoter region of KL (34.1 ± 4.1% vs. 14.6 ± 3.4%, P < 0.01). In PBCCs and vasculature, KL gene expression correlated inversely with pro-inflammatory markers and directly with anti-inflammatory markers. sKL serum levels presented similar associations with the expression levels of pro- and anti-inflammatory markers in PBCCs. The differences in KL expression levels in PBCCs and in serum sKL levels with respect to control group was even greater in those CVD patients with macroscopically observable atheromatous plaques. We conclude that promoter methylation-mediated downregulation of KL gene expression in PBCCs is associated with the pro-inflammatory status in atherosclerotic vascular disease.

Sodium-glucose co-transporter-2 inhibitors increase Klotho in patients with diabetic kidney disease: A clinical and experimental study.

Sodium-glucose co-transporter-2 inhibitors (SGLT2i) provide cardiorenal protection. However, the molecular mechanisms remain poorly understood. We explored the impact of SGLT2i on Klotho, a kidney-derived protein with antiaging, renal-protective and heart-protective properties. A real world prospective observational study addressed the impact of initiating SGLT2i (canagliflozin, dapagliflozin, empagliflozin) or dipeptidyl peptidase-4 inhibitors (DPP4i) in patients with early diabetic kidney disease (DKD). Serum and urinary soluble Klotho, albuminuria and serum and urinary tumor necrosis factor-alpha (TNFa) were measured. The effect of SGLT2i on Klotho mRNA and protein was explored in vitro in kidney proximal tubular cells stressed with high glucose concentrations to simulate the diabetic milieu, albumin to simulate albuminuria, and the inflammatory cytokine TWEAK to simulate the inflammatory environment in DKD. Baseline urinary Klotho was negatively associated with albuminuria (r - 0.45, P < 0.001) and urinary TNFa (r - 0.40, P < 0.01). Both DPP4i and SGLT2i reduced HbA1c similarly, but only SGLT2i decreased eGFR, albuminuria and urinary TNFa and increased (P < 0.001) serum (5.2 %) and urinary Klotho (38.9 %). Changes in urinary TNFa (ß - 0.53, P = 0.001) and albuminuria (ß - 0.31, P < 0.05) were independently associated with changes in urinary Klotho (adjusted R2 = 0.54, P < 0.001). Studies in renal tubular cells demonstrated that high glucose, albumin and TWEAK decreased Klotho mRNA expression and protein levels, an effect similarly prevented by SGLT2i. SGLT2i increase Klotho availability in type 2 diabetic patients with poorly controlled diabetes and early DKD, as well as in stressed tubular cells. This effect on Klotho may contribute to the kidney and heart protection afforded by SGLT2i.

Klotho as a biomarker of subclinical atherosclerosis in patients with moderate to severe chronic kidney disease.

Chronic kidney disease (CKD) has been associated with a higher risk of cardiovascular disease (CVD). CKD patients present a decrease in the levels of the protein Klotho that accompanies the decrease in kidney function. This protein has been related to protective effects against CVD. However, it is unclear whether circulating Klotho, and its expression in peripheral blood cells (PBCs) are also associated with subclinical atherosclerosis in CKD. The present study aimed to study the relationship between Klotho and subclinical atherosclerosis in a population of patients with moderate to severe CKD. We determined the serum levels and gene expression in PBCs levels of Klotho and three inflammatory cytokines in 103 patients with CKD and investigated their relationship with two surrogate markers of subclinical atherosclerotis: ankle-brachial index (ABI) and carotid intima-media thickness (CIMT). Patients with subclinical atherosclerosis presented lower serum and PBCs expression levels of Klotho. Both variables were associated with the presence of subclinical atherosclerosis, being directly related with ABI and inversely with CIMT (P < 0.0001 for both). Multiple regression analysis demonstrated that both variables were significant determinants for ABI (adjusted R2 = 0.511, P < 0.0001) and CIMT (adjusted R2 = 0.445, P < 0.0001), independently of traditional and emergent cardiovascular risk factors. Moreover, both constituted protective factors against subclinical atherosclerosis [OR: 0.993 (P = 0.002) and 0.231 (P = 0.025), respectively]. Receiver operating characteristic analysis pointed to the utility of serum Klotho (area under the curve [AUC]: 0.817, 95% CI: 0.736-0.898, P < 0.001) and its gene expression in PBCs (AUC: 0.742, 95% CI: 0.647-0.836, P < 0.001) to distinguish subclinical atherosclerosis. The reductions in serum and PBCs expression levels of Klotho in CKD patients are independently associated with the presence of for subclinical atherosclerosis. Further research exploring whether therapeutic approaches to maintain or elevate Klotho could reduce the impact of CVD in CKD patients is warranted.

Extracellular water/total body water ratio as predictor of mortality in hemodialysis patients.

BACKGROUND: Overhydration is a predictor of mortality in hemodialysis (HD) patients. Bioimpedance spectroscopy (BIS) is used to determine the body composition. Extracellular Water/Total Body Water (ECW/TBW) ratio has been proposed to predict mortality. METHODS: Multicenter, prospective, observational, proof-of-concept study to estimate the impact of ECW/TBW in global and cardiovascular mortality and the relationship with cardiovascular biomarkers. The study included 60 patients (mean age, 71.8 ± 11.4 years; mean time on HD, 52.3 ± 30.8 months) with a median follow-up of 30.5 months (IQ range, 17.2-34 months). RESULTS: Post-dialysis ECW/TBW was directly associated with NT-proBNP and cTnT. During the study 28 patients died, most of them (43%) due to cardiovascular events. Compared to the survivors, these subjects had a higher post-dialysis ECW/TBW ratio (p = 0.006), while for cardiovascular mortality the only significant difference was a higher pre-dialysis ECW/TBW. The ability of post-dialysis ECW/TBW ratio to predict all-cause mortality had an area under the ROC curve (AUC) of 0.71 (CI 95%, 0.57-0.81; p = 0.002), with a cutoff point of 0.5023. For cardiovascular mortality the AUC was 0.66 (CI 95%, 0.52-0.77; p = 0.045), with a cutoff point of 0.4713. CONCLUSIONS: The post-dialysis ECW/TBW ratio measured by BIS can be a predictor of all-cause and cardiovascular mortality.

Association between serum levels of Klotho and inflammatory cytokines in cardiovascular disease: a case-control study.

Decrease in soluble anti-aging Klotho protein levels is associated to cardiovascular disease (CVD). Diverse studies have shown a bidirectional relationship between Klotho and inflammation, a risk factor for the development of CVD. In this work we aimed to evaluate the association between Klotho and inflammatory cytokines levels in the context of human CVD.The study included 110 patients with established CVD and preserved renal function, and a control group of 22 individuals without previous history of cardiovascular events. Serum Klotho and IL10 levels were significantly lower in the CVD group. Inflammatory status, marked by the TNFα/IL10 ratio and the C-reactive protein (CRP) levels, was significantly increased in the group of patients with established CVD. Soluble Klotho levels were directly correlated with eGFR (r=0.217) and IL10 (r=0.209) and inversely correlated with age (r=-0.261), CRP (r=-0.203), and TNFα/IL10 (r=-0.219). This association with TNFα/IL10 remained significant in age-matched subgroups. Multiple logistic regression analysis showed that age, smoking and the neutrophil-to-lymphocyte ratio (NLR) constituted risk factors for the presence of CVD, while Klotho was a protective factor.In conclusion, in patients with established CVD, the reduction in soluble Klotho is associated with a pro-inflammatory status marked by lower IL10 concentrations and higher TNFα/IL10 ratio and CRP levels.

Fibroblast growth factor 23 expression in human calcified vascular tissues.

Vascular calcification is a major risk for cardiovascular disease and implies the transformation of smooth muscle cells to an osteoblastic phenotype as a consequence of dysregulation of calcium and phosphate metabolism. Fibroblast growth factor (FGF) 23 is the most potent phosphate regulator. Observational studies suggest that high levels of FGF23 are related to cardiovascular morbidity and mortality. In this work, we determined the levels of both the intact and the carboxi-terminal fragments of circulating FGF23 in 133 patients with established cardiovascular disease, the expression of FGF23, its receptors 1 and 3, and its co-receptor Klotho in vascular fragments of aorta, carotid and femoral in 43 out of this group of patients, and in a control group of 20 organ donors. Patients with atherosclerosis and vascular calcification presented increased levels of FGF23 respect to the control group. Vascular immunoreactivity for FGF23 was also significantly increased in patients with vascular calcification as compared to patients without calcification and to controls. Finally, gene expression of FGF23 and RUNX2 were also higher and directly related in vascular samples with calcification. Conversely, expression of Klotho was reduced in patients with cardiovascular disease when comparing to controls. In conclusion, our findings link the calcification of the vascular tissue with the expression of FGF23 in the vessels and with the elevation of circulating levels this hormone.

FGF23 and Klotho Levels are Independently Associated with Diabetic Foot Syndrome in Type 2 Diabetes Mellitus.

BACKGROUND: Diabetic foot syndrome (DFS) is a prevalent complication in the diabetic population and a major cause of hospitalizations. Diverse clinical studies have related alterations in the system formed by fibroblast growth factor (FGF)-23 and Klotho (KL) with vascular damage. In this proof-of-concept study, we hypothesize that the levels of FGF23 and Klotho are altered in DFS patients. METHODS: Twenty patients with limb amputation due to DFS, 37 diabetic patients without DFS, and 12 non-diabetic cadaveric organ donors were included in the study. Serum FGF23/Klotho and inflammatory markers were measured by enzyme-linked immunosorbent assay (ELISA). Protein and gene expression levels in the vascular samples were determined by immunohistochemistry and quantitative real-time PCR, respectively. RESULTS: Serum Klotho is significantly reduced and FGF23 is significantly increased in patients with DFS (p < 0.01). Vascular immunoreactivity and gene expression levels for Klotho were decreased in patients with DFS (p < 0.01). Soluble Klotho was inversely related to serum C-reactive protein (r = -0.30, p < 0.05). Vascular immunoreactivities for Klotho and IL6 showed an inverse association (r = -0.29, p < 0.04). Similarly, vascular gene expression of KL and IL6 were inversely associated (r = -0.31, p < 0.05). Logistic regression analysis showed that higher Klotho serum concentrations and vascular gene expression levels were related to a lower risk of DFS, while higher serum FGF23 was associated with a higher risk for this complication. CONCLUSION: FGF23/Klotho system is associated with DFS, pointing to a new pathophysiological pathway involved in the development and progression of this complication.

[Optimisation of nutritional screening tool CIPA: are two parameters of protein really necessary?] / Optimización del cribado nutricional CIPA: ¿son necesarios dos parámetros proteicos?

INTRODUCTION: the preliminary nutritional screening tool CIPA (food intake, proteins, anthropometry) is positive when it fulfills one of the following: control food intake (CI) 48-72 h < 50%, albumin < 3 g/dl, total protein < 5 g/dl, body mass index (BMI) < 18,5 kg/m2 or mid-upper arm circumference (MUAC) ≤ 22,5 cm. The use of two protein parameters increases costs and difficulty; one of them can be suppressed without affecting validity. OBJECTIVES: to evaluate the effectiveness of screening CIPA after exclusion of total protein. METHOD: prospective study of hospitalized patients; prevalence or risk of malnutrition was evaluated through CIPA and Subjective Global Assessment (SGA). Hospital malnutrition according to complete CIPA screening (with total proteins and albumin, [CIPAc] and without total proteins [CIPAw/p]) and concordance between both methods were analyzed, as well as the association of the positive screening result with clinical outcomes. RESULTS: three hundred and forty-three patients were analyzed. The prevalence or risk of malnutrition identified by complete CIPA (c) was 38.19% (33.02-43.36); by CIPA without protein (w/p), 37.32% (32.17-42.46); and SGA was 29.15% (24.32-33.99). Kappa index: 0.981 between both CIPAs, p < 0.001. Both CIPA and SGA detect patients with higher mortality in hospital and one month after discharge. Early readmission was higher in positive CIPA, statistical significantly in CIPAw/p (screening with positive results 21.88% vs screening with negative results 13.49%, p = 0.044), SGA 20.01% vs 15.23%, p = 0.28. Length of stay was higher in patients with positive screening in CIPAc, CIPAw/p and SGA. CONCLUSIONS: CIPAw/p is equally or more effective than the previously validated full CIPA; therefore, it could replace the latter saving costs. The prevalence of malnutrition is high in both variants and they are able to predict which patient has worse clinical prognosis.

Introducción: el cribado nutricional CIPA (control de ingestas, proteínas, antropometría) preliminar es positivo cuando se cumple uno de los siguientes parámetros: control de ingestas (CI) 48-72 h < 50%, albúmina < 3 g/dl, proteínas totales < 5 g/dl, índice de masa corporal (IMC) < 18,5 kg/m2 o circunferencia del brazo (CB) ≤ 22,5 cm (cuando el paciente no se puede pesar/tallar). El uso de dos parámetros proteicos aumenta costes y complejidad, pudiendo suprimirse uno de ellos sin afectar su validez.Objetivos: evaluar la efectividad del cribado CIPA tras exclusión de proteínas totales.Métodos: estudio prospectivo de pacientes hospitalizados valorando prevalencia o riesgo de desnutrición a través de CIPA y valoración global subjetiva (VGS). Análisis de desnutrición hospitalaria según el cribado CIPA completo (con proteínas totales y albúmina, CIPAc) y sin proteínas totales (CIPAs/p), y análisis de la concordancia entre ambos métodos. Estudio de la asociación del resultado positivo del cribado con factores pronósticos.Resultados: se analizaron 343 pacientes. Prevalencia de desnutrición: CIPAc 38,19% (33,02-43,36), CIPAs/p 37,32% (32,17-42,46), VGS 29,15% (24,32-33,99). Índice de correlación Kappa: 0,981 entre ambos CIPA, p < 0,001. Tanto las dos versiones de CIPA como la VGS detectan pacientes con mayor mortalidad hospitalaria y al mes del alta. Reingreso precoz: mayor en CIPA positivo, estadísticamente significativo en CIPAs/p (cribado positivo 21,88% vs. negativo 13,49%, p = 0,044), VGS 20,01% vs. 15,23%, p = 0,28. Estancia media: superior en pacientes con cribado positivo en las dos variantes de CIPA y en VGS.Conclusiones: CIPAs/p es igual o más eficaz que CIPAc validado previamente, por lo que puede sustituir a este último ahorrando costes. La prevalencia de desnutrición es elevada en ambas variantes y son capaces de identificar al paciente con peor pronóstico clínico.

Optimización del cribado nutricional cipa: ¿son necesarios dos parámetros proteicos? / Optimisation of nutritional screening tool CIPA: are two parameters of protein really necessary?

Introducción: el cribado nutricional CIPA (control de ingestas, proteínas, antropometría) preliminar es positivo cuando se cumple uno de los siguientes parámetros: control de ingestas (CI) 48-72 h < 50%, albúmina < 3 g/dl, proteínas totales < 5 g/dl, índice de masa corporal (IMC) < 18,5 kg/m2 o circunferencia del brazo (CB) ≤ 22,5 cm (cuando el paciente no se puede pesar/tallar). El uso de dos parámetros proteicos aumenta costes y complejidad, pudiendo suprimirse uno de ellos sin afectar su validez. Objetivos: evaluar la efectividad del cribado CIPA tras exclusión de proteínas totales. Métodos: estudio prospectivo de pacientes hospitalizados valorando prevalencia o riesgo de desnutrición a través de CIPA y valoración global subjetiva (VGS). Análisis de desnutrición hospitalaria según el cribado CIPA completo (con proteínas totales y albúmina, CIPAc) y sin proteínas totales (CIPAs/p), y análisis de la concordancia entre ambos métodos. Estudio de la asociación del resultado positivo del cribado con factores pronósticos. Resultados: se analizaron 343 pacientes. Prevalencia de desnutrición: CIPAc 38,19% (33,02-43,36), CIPAs/p 37,32% (32,17-42,46), VGS 29,15% (24,32-33,99). Índice de correlación Kappa: 0,981 entre ambos CIPA, p < 0,001. Tanto las dos versiones de CIPA como la VGS detectan pacientes con mayor mortalidad hospitalaria y al mes del alta. Reingreso precoz: mayor en CIPA positivo, estadísticamente significativo en CIPAs/p (cribado positivo 21,88% vs. negativo 13,49%, p = 0,044), VGS 20,01% vs. 15,23%, p = 0,28. Estancia media: superior en pacientes con cribado positivo en las dos variantes de CIPA y en VGS. Conclusiones: CIPAs/p es igual o más eficaz que CIPAc validado previamente, por lo que puede sustituir a este último ahorrando costes. La prevalencia de desnutrición es elevada en ambas variantes y son capaces de identificar al paciente con peor pronóstico clínico

Introduction: the preliminary nutritional screening tool CIPA (food intake, proteins, anthropometry) is positive when it fulfills one of the following: control food intake (CI) 48-72 h < 50%, albumin < 3 g/dl, total protein < 5 g/dl, body mass index (BMI) < 18,5 kg/m2 or mid-upper arm circumference (MUAC) ≤ 22,5 cm. The use of two protein parameters increases costs and difficulty; one of them can be suppressed without affecting validity. Objectives: to evaluate the effectiveness of screening CIPA after exclusion of total protein. Method: prospective study of hospitalized patients; prevalence or risk of malnutrition was evaluated through CIPA and Subjective Global Assessment (SGA). Hospital malnutrition according to complete CIPA screening (with total proteins and albumin, [CIPAc] and without total proteins [CIPAw/p]) and concordance between both methods were analyzed, as well as the association of the positive screening result with clinical outcomes. Results: three hundred and forty-three patients were analyzed. The prevalence or risk of malnutrition identified by complete CIPA (c) was 38.19% (33.02-43.36); by CIPA without protein (w/p), 37.32% (32.17-42.46); and SGA was 29.15% (24.32-33.99). Kappa index: 0.981 between both CIPAs, p < 0.001. Both CIPA and SGA detect patients with higher mortality in hospital and one month after discharge. Early readmission was higher in positive CIPA, statistical significantly in CIPAw/p (screening with positive results 21.88% vs screening with negative results 13.49%, p = 0.044), SGA 20.01% vs 15.23%, p = 0.28. Length of stay was higher in patients with positive screening in CIPAc, CIPAw/p and SGA. Conclusions: CIPAw/p is equally or more effective than the previously validated full CIPA; therefore, it could replace the latter saving costs. The prevalence of malnutrition is high in both variants and they are able to predict which patient has worse clinical prognosis

Effects of Pentoxifylline on Soluble Klotho Concentrations and Renal Tubular Cell Expression in Diabetic Kidney Disease.

OBJECTIVE: The effect of pentoxifylline on Klotho levels in patients with type 2 diabetes mellitus with chronic kidney disease (CKD) was assessed in a post hoc analysis of the Pentoxifylline for Renoprotection in Diabetic Nephropathy (PREDIAN) trial. RESEARCH DESIGN AND METHODS: Circulating and urinary tumor necrosis factor-α (TNF-α) and Klotho were measured before and after 1 year of pentoxifylline. The effect on Klotho expression was assessed in cultured renal tubular cells. RESULTS: Pentoxifylline administration resulted in decreased serum and urinary TNF-α, whereas serum and urinary Klotho increased significantly. Changes in urinary Klotho, urinary TNF-α, and phosphorus were associated with changes in serum Klotho; changes in estimated glomerular filtration rate, urinary TNF-α, and albuminuria were related to urinary Klotho variation. In renal tubular cells, pentoxifylline prevented the decrease in Klotho expression induced by inflammatory cytokines or albumin. CONCLUSIONS: Pentoxifylline increased Klotho levels in patients with diabetes with stage 3-4 CKD and prevented reduced Klotho expression in vitro. This beneficial effect may be related to anti-inflammatory and antialbuminuric activity.

Perfil antiinflamatorio del paricalcitol en el receptor de trasplante renal / Anti-inflammatory profile of paricalcitol in kidney transplant recipients

Antecedentes y objetivos: El paricalcitol, un activador selectivo del receptor de la vitamina D, se utiliza en el tratamiento del hiperparatiroidismo secundario en el receptor de trasplante renal. Estudios tanto clínicos como experimentales realizados en pacientes renales no trasplantados muestran propiedades antiinflamatorias para esta molécula. En este estudio exploratorio, hemos evaluado el perfil antiinflamatorio del paricalcitol en receptores de trasplante renal. Métodos: Treinta y un pacientes trasplantados con hiperparatiroidismo secundario completaron 3 meses de terapia con paricalcitol oral (1μg/día). Se determinaron las concentraciones séricas y los niveles de expresión génica de citocinas inflamatorias en células mononucleares de sangre periférica al inicio y al final del estudio. Resultados: El paricalcitol provocó una disminución significativa en los niveles de hormona paratiroidea, sin cambios en los de calcio y fósforo. Además, indujo una reducción en las concentraciones séricas de la interleucina (IL)-6 y del factor de necrosis tumoral alfa (TNF-α), con reducciones porcentuales respecto al estado basal de un 29% (p<0,05) y de un 9,5% (p<0,05), respectivamente. Los niveles de expresión génica de la IL-6 y del TNF-α en células mononucleares de sangre periférica experimentaron un descenso de un 14,1% (p<0,001) y de un 34,1% (p<0,001), respectivamente. La proporción entre las citocinas proinflamatorias (TNF-α e IL-6) y la antiinflamatoria IL-10, tanto para los niveles séricos como para los de expresión génica, también disminuyó significativamente. Conclusiones: La administración del paricalcitol a receptores de trasplante renal se asocia con efectos beneficiosos sobre su estado inflamatorio, lo que podría asociarse a un potencial beneficio clínico (AU)

Background and objectives: Paricalcitol, a selective vitamin D receptor activator, is used to treat secondary hyperparathyroidism in kidney transplant patients. Experimental and clinical studies in non-transplant kidney disease patients have found this molecule to have anti-inflammatory properties. In this exploratory study, we evaluated the anti-inflammatory profile of paricalcitol in kidney-transplant recipients. Methods: Thirty one kidney transplant recipients with secondary hyperparathyroidism completed 3 months of treatment with oral paricalcitol (1μg/day). Serum concentrations and gene expression levels of inflammatory cytokines in peripheral blood mononuclear cells were analysed at the beginning and end of the study. Results: Paricalcitol significantly decreased parathyroid hormone levels with no changes in calcium and phosphorous. It also reduced serum concentrations of interleukin (IL)-6 and tumour necrosis factor-alpha (TNF-α) by 29% (P<0.05) and 9.5% (P<0.05) compared to baseline, respectively. Furthermore, gene expression levels of IL-6 and TNF-α in peripheral blood mononuclear cells decreased by 14.1% (P<0.001) and 34.1% (P<0.001), respectively. The ratios between pro-inflammatory cytokines (TNF-α and IL-6) and anti-inflammatory cytokines (IL-10), both regarding serum concentrations and gene expression, also experienced a significant reduction. Conclusions: Paricalcitol administration to kidney transplant recipients has been found to have beneficial effects on inflammation, which may be associated with potential clinical benefits (AU)

Soluble levels and endogenous vascular gene expression of KLOTHO are related to inflammation in human atherosclerotic disease.

Atherosclerosis is a chronic inflammatory disorder affecting the artery wall. Klotho, an anti-aging factor expressed in the vessel walls that participates in the maintenance of vascular homeostasis, can be down-regulated by inflammation. In this proof-of-concept work we seek to characterize the arterial KLOTHO expression in the vascular wall, as well as the serum concentration of this protein, in a group of patients with clinical atherosclerotic disease. In addition, we aim to analyze the relationship between Klotho and inflammation. Vascular samples were obtained from 27 patients with atherosclerotic disease under an elective vascular surgery procedure, and from 11 control subjects (cadaveric organ donation programme). qRT-PCR was performed to analyze the gene expression of KLOTHO, TNF-α, IL-6, and IL-10 Serum levels of soluble KLOTHO were measured by ELISA. As compared with control subjects, serum concentrations and vascular expression of Klotho were lower in patients with atherosclerotic vascular disease, whereas inflammatory status was significantly higher. There was a negative and significant correlation between inflammatory parameters and Klotho. After controlling for the effect of other variables, partial correlation showed a direct relationship between vascular KLOTHO gene expression and IL-10 mRNA levels, whereas there was a negative association with serum LDL concentrations and vascular TNF-α expression. Our study indicates an inverse interrelationship between inflammation and Klotho in atherosclerosis. Further studies are necessary to elucidate whether the inflammatory state causes Klotho deficiency or, on the contrary, reduction of Klotho could be responsible for greater inflammation, and finally, to investigate the potential clinical relevance of this association.

Anti-inflammatory profile of paricalcitol in kidney transplant recipients. / Perfil antiinflamatorio del paricalcitol en el receptor de trasplante renal.

BACKGROUND AND OBJECTIVES: Paricalcitol, a selective vitamin D receptor activator, is used to treat secondary hyperparathyroidism in kidney transplant patients. Experimental and clinical studies in non-transplant kidney disease patients have found this molecule to have anti-inflammatory properties. In this exploratory study, we evaluated the anti-inflammatory profile of paricalcitol in kidney-transplant recipients. METHODS: Thirty one kidney transplant recipients with secondary hyperparathyroidism completed 3 months of treatment with oral paricalcitol (1µg/day). Serum concentrations and gene expression levels of inflammatory cytokines in peripheral blood mononuclear cells were analysed at the beginning and end of the study. RESULTS: Paricalcitol significantly decreased parathyroid hormone levels with no changes in calcium and phosphorous. It also reduced serum concentrations of interleukin (IL)-6 and tumour necrosis factor-alpha (TNF-α) by 29% (P<0.05) and 9.5% (P<0.05) compared to baseline, respectively. Furthermore, gene expression levels of IL-6 and TNF-α in peripheral blood mononuclear cells decreased by 14.1% (P<0.001) and 34.1% (P<0.001), respectively. The ratios between pro-inflammatory cytokines (TNF-α and IL-6) and anti-inflammatory cytokines (IL-10), both regarding serum concentrations and gene expression, also experienced a significant reduction. CONCLUSIONS: Paricalcitol administration to kidney transplant recipients has been found to have beneficial effects on inflammation, which may be associated with potential clinical benefits.

Effect of Paricalcitol on FGF-23 and Klotho in Kidney Transplant Recipients.

BACKGROUND: Paricalcitol decreases intact parathyroid hormone and the frequency of secondary hyperparathyroidism after kidney transplantation. This proof-of-concept study aimed to assess the effect of paricalcitol on fibroblast growth factor-23/KLOTHO axis in renal transplants. METHODS: Twenty-nine subjects with secondary hyperparathyroidism received oral paricalcitol 1 µg/d for 3 months, and 8 patients matched by age, sex, and creatinine clearance, but with intact parathyroid hormone less than 100 pg/mL, were included as controls. RESULTS: Intact parathyroid hormone decreased in paricalcitol-treated patients (P < 0.0001). Serum fibroblast growth factor-23 enhanced (P < 0.01), whereas KLOTHO concentrations showed a trend to increase (P = 0.067). KLOTHO gene expression in peripheral blood mononuclear cells increased by 45.7% in paricalcitol-treated patients (P < 0.01), without change in controls. Paricalcitol administration resulted in a median percent decrease of 56% in methylated DNA levels of KLOTHO promoter (P < 0.001). The ratio of the unmethylated/methylated KLOTHO promoter DNA did not change in controls, but it increased by 177% in paricalcitol-treated subjects (P < 0.0001). The increase in this ratio was independently associated with the change in serum KLOTHO (r = 0.55, P < 0.01) and messenger RNA expression levels (r = 0.40, P < 0.05). CONCLUSIONS: Paricalcitol administration to renal transplant patients significantly reduced intact parathyroid hormone and increased fibroblast growth factor-23, with a trend to increase in serum KLOTHO. Paricalcitol-treated patients showed a decrease in the methylation of the KLOTHO promoter with an increment in the ratio of un-methyated/methylated DNA, which was associated with an increase of KLOTHO gene expression levels and serum KLOTHO concentrations. Long-term studies are needed to assess whether paricalcitol-induced increase in KLOTHO gene expression and serum concentrations may translate into beneficial clinical effects.

Influence of Klotho gene polymorphisms on vascular gene expression and its relationship to cardiovascular disease.

Klotho protein has been associated with beneficial effects that contribute to the maintenance of cardiovascular health. Diverse studies suggest that alterations in the levels of this molecule may be associated with pathophysiological abnormalities that result in increased cardiovascular risk. The primary aim of this proof-of-concept study was to analyse the existence of a potential link between Klotho gene polymorphisms and the expression level of this gene in the vascular wall, and additionally with the incidence of cardiovascular disease and cardiovascular risk factors. Our results indicate that the variant G-395A, located in the promoter region, influences Klotho gene vascular expression and is associated with the incidence of diabetes. Similarly, the exonic variant KL-VS was associated with the incidence of atherosclerotic vascular disease and coronary artery disease. Moreover, vascular expression levels of Klotho were related with the incidence of diabetes mellitus and coronary artery disease. These findings, which need to be confirmed in larger studies, suggest a potential role of Klotho in the pathogenesis of vascular damage.

Klotho in cardiovascular disease: Current and future perspectives.

Protein Klotho, beyond its role as a regulator of the phosphatemia, is also involved in the maintaining of the cardiovascular health, being associated its alterations with the development of cardiovascular damage and increased morbi-mortality. For all this, nowadays Klotho is the subject of a thorough research which is focused on uncover its intimate mechanisms of action, and in analyzing the utility of its modulation as a potential strategy with clinical applicability. Molecular mechanisms of Klotho are not well understood but an emerging research area links Klotho deficiency with vascular pathology. Changes in this protein have been associated with cardiovascular-related complications like inflammation, vascular calcification, and endothelial dysfunction. All this is particularly relevant if considering the recent discovery of Klotho expression in vascular tissue.