Cost-effectiveness analysis of cinacalcet vs. paricalcitol in the treatment of hyperparathyroidism secondary to chronic kidney disease / Análise de custo-efetividade do cinacalcete vs. paricalcitol no tratamento do hiperparatireoidismo secundário à doença renal crônica

ABSTRACT Introduction For the reduction of PTH levels, two classes of drugs are available in the Brazilian market: non-selective and selective vitamin D receptor activators and calcimimetics. Among the mentioned drugs, the SUS provides oral calcitriol, paricalcitol and cinacalcet. Objectives: Develop cost-effectiveness (CE) and budgetary impact (BI) analysis of cinacalcet versus paricalcitol for patients on dialysis with SHPT, from the perspective of SUS. Methodology: A decision tree model was constructed for CE analysis, which considered the outcome of avoided parathyroidectomy and a time horizon of 1 year. As for the BI analysis, two scenarios were considered, one of which was measured demand and other epidemiological, based on data from the Brazilian Society of Nephrology (BSN). Results: The CE analysis showed that the use of cinacalcet results in one-off savings of R$1,394.64 per year and an incremental effectiveness of 0.08, in relation to avoided parathyroidectomy. The incremental CE ratio (ICER) was - R$ 17,653.67 per avoided parathyroidectomy for cinacalcet, as it was more effective and cheaper compared to paricalcitol. As for the BI analysis, it was estimated that the incremental BI with the expansion of the use of cinacalcet in the SUS will be between - R$ 1,640,864.62 and R$ 166,368.50 in the first year, considering the main and the epidemiological scenarios. At the end of 5 years after the expansion of use, an BI was estimated between - R$ 10,740,743.86 and - R$ 1,191,339.37; considering the same scenarios. Conclusion: Cinacalcet was dominant to avoid parathyroidectomies, being cost-effective.

RESUMO Introdução: Para a redução dos níveis do paratormônio (PTH) estão disponíveis no mercado brasileiro duas classes de medicamentos: ativadores do receptor da vitamina D (não seletivos e seletivos) e calcimiméticos. Dentre os medicamentos supracitados, o SUS disponibiliza calcitriol oral, paricalcitol e cinacalcete. Objetivos: Desenvolver análise de custo-efetividade (CE) e de impacto orçamentário (IO) do cinacalcete versus paricalcitol para pacientes em diálise com HPTS, na perspectiva do SUS. Metodologia: Foi construído um modelo de árvore de decisão para a análise de CE, que considerou o desfecho paratireoidectomia evitada e um horizonte temporal de 1 ano. Quanto à análise de IO, foram considerados dois cenários, um de demanda aferida e outro de abordagem epidemiológica, baseado nos dados da Sociedade Brasileira de Nefrologia (SBN). Resultados: A análise de CE mostrou que o uso de cinacalcete resulta em economia de R$ 1.394,64 ao ano e efetividade incremental de 0,08, em relação a paratireoidectomia evitada. A razão de CE incremental (RCEI) foi de - R$ 17.653,67 por paratireoidectomia evitada para o cinacalcete, já que se mostrou mais efetivo e mais barato comparado ao paricalcitol. Estimou-se que o IO incremental com a ampliação do uso do cinacalcete no SUS estará entre - R$ 1.640.864,62 e R$ 166.368,50 no primeiro ano, considerando os cenários principal e epidemiológico baseado nos dados da SBN. Já ao final de 5 anos após a ampliação do uso, estimou-se um impacto incremental entre - R$ 10.740.743,86 e - R$ 1.191.339,37; considerando os mesmos cenários. Conclusão: Cinacalcete foi dominante para evitar paratireoidectomias, sendo custo-efetivo.

Cost-effectiveness analysis of intravenous paricalcitol vs. oral calcitriol in the treatment of hyperparathyroidism secondary to chronic kidney disease / Análise de custo-efetividade do paricalcitol intravenoso vs. calcitriol oral no tratamento do hiperparatireoidismo secundário à doença renal crônica

Abstract Introduction: Hyperparathyroidism (SHPT) secondary to chronic kidney disease (CKD) is characterized by high levels of parathyroid hormone (PTH), hyperplasia of the parathyroid glands and cardiovascular disease. Selective and non-selective and selective vitamin D-receptor activators, calcimimetics, are available in the Brazilian market to reduce PTH levels. Objectives: To develop a cost-effectiveness (C/E) and budgetary impact (BI) analysis of intravenous paricalcitol vs. oral calcitriol for patients on dialysis with SHPT, from the perspective of the Brazilian Public Health Care System (SUS). Methodology: We built a decision-tree model to analyze C/E, which considered the outcome of avoided death and a time horizon of 1 year. As for the BI analysis, two scenarios were considered, one of demand and one of epidemiological approach, based on data from the Brazilian Society of Nephrology. Results: The analysis showed that the C/E ratio was R$ 1,213.68 per year, and an incremental effectiveness of 0.032, referring to avoided death. The incremental C/E ratio was R$37,927.50 per death averted by paricalcitol. It was estimated that the incremental BI with the expansion of paricalcitol use will be between R$1,600,202.28 and R$4,128,565.65 in the first year, considering the main and epidemiological scenarios. At the end of 5 years after the expansion of its use, an incremental BI was estimated between R$ 48,596,855.50 and R$ 62,90,555.73. Conclusion: Intravenous paricalcitol has superior efficacy and similar safety to oral calcitriol, reducing the overall mortality of dialysis patients, although it implies a higher cost.

Resumo Introdução: O hiperparatireoidismo secundário (HPTS) à doença crônica renal (DRC) é caracterizado por elevados níveis de paratormônio (PTH), hiperplasia das glândulas paratireoides e doença cardiovascular. Para a redução dos níveis do PTH, estão disponíveis no mercado brasileiro os ativadores não seletivos e seletivos do receptor da vitamina D e os calcimiméticos. Objetivos: Desenvolver análise de custo-efetividade (C/E) e de impacto orçamentário (IO) do paricalcitol intravenoso vs. calcitriol oral para pacientes em diálise com HPTS, na perspectiva do Sistema Único de Saúde. Metodologia: Foi construído um modelo de árvore de decisão para a análise de C/E, que considerou o desfecho morte evitada e um horizonte temporal de 1 ano. Quanto à análise de IO, foram considerados dois cenários, sendo um de demanda aferida e um de abordagem epidemiológica, baseado nos dados da Sociedade Brasileira de Nefrologia. Resultados: A análise mostrou que a relação de C/E foi de R$ 1.213,68 ao ano, e uma efetividade incremental de 0,032, referente à morte evitada. A razão de C/E incremental foi de R$ 37.927,50 por morte evitada para o paricalcitol. Estimou-se que o IO incremental com a ampliação do uso do paricalcitol estará entre R$ 1.600.202,28 e R$ 4.128.565,65 no primeiro ano, considerando os cenários principal e o epidemiológico. Já no fim de 5 anos após a ampliação do uso, estimou-se IO incremental entre R$ 48.596.855,50 e R$ 62.90.555,73. Conclusão: O paricalcitol intravenoso tem eficácia superior e segurança semelhante ao comparador calcitriol oral, diminuindo a mortalidade geral dos pacientes em diálise, embora implique maior custo.

Can paricalcitol increase the effectiveness of n-acetylcysteine in contrast induced acute kidney prophylaxis in rats? A biochemical and histopathological study / ¿Puede el paricalcitol aumentar la eficacia de la n-acetilcisteína en la profilaxis renal aguda inducida por contraste en ratas? Un estudio bioquímico e histopatológico

SUMMARY: N-Acetylcysteine (NAC) is used for contrast induced acut kidney injury (CI-AKI) prophylaxis because of its antioxidant effects. Paricalcitol, which has reno-protective effects, is likely to provide a more effective prophylaxis when added to NAC treatment. The study was designed based on this hypothesis. The study was organised to include 4 groups each consisting of 7 rats. Group 1 was the control group, and Group 2 included rats with CI-AKI. Rats in Group 3 were administered NAC at a dose of 100 mg/kg via oral gavage once a day for 5 days. Rats in group 4 were administered paricalcitol at a dose of 0.4 mcg/kg once a day for 5 days in addition to NAC. CI-AKI was induced after the treatments in both groups. The study was terminated on the sixth day. Samples were collected from the rats' sera and kidney tissues to study oxidant and antioxidant parameters; kidney function tests were also studied. There were significant differences between the contrast nephropathy group (Group 2) and NAC and NAC+paricalcitol groups with respect to serum urea and creatinine levels. When the same groups were compared regarding oxidant (TOS-MDA) and antioxidant (TAC-Paraoxonase) parameters, we observed that the oxidant parameters increased in serum and kidney tissue samples with NAC use, and that effect was strengthened by the addition of paricalcitol to NAC treatment. However, despite increased antioxidant effectiveness, we observed no decrease in urea and creatinine levels when paricalcitol was added for CI-AKI in rats. There was no significant difference between Group 3 and Group 4. Paricalcitol provides a more potent antioxidant effect in both serum and kidney tissue samples when added to NAC treatment in rats with CI-AKI. Despite increased antioxidant parameters, however, paricalcitol does not provide a significant decrease in urea and creatinine levels.

RESUMEN: Debido a sus efectos atioxidantes la N- acetilcisteína (NAC) se usa para la profilaxis de la lesión renal aguda inducida por contraste (CI-AKI). Es probable que el paricalcitol, que tiene efectos renoprotectores, proporcione una profilaxis más eficaz cuando se agrega al tratamiento con NAC. En base a esta hipótesis el estudio fue diseñado para incluir cuatro grupos cada uno compuesto por siete ratas. El grupo 1 fue el grupo control y el grupo 2 incluyó ratas con CI-AKI. A las ratas del Grupo 3 se les administró NAC con una dosis de 100 mg/kg por sonda oral una vez al día, durante 5 días. A las ratas del grupo 4 se les administró paricalcitol a una dosis de 0,4 mcg/kg una vez al día durante 5 días, además de NAC. Se indujo CI-AKI después de los tratamientos en ambos grupos. El estudio finalizó el sexto día. Se recolectaron muestras de suero y tejidos renales de ratas para estudiar los parámetros oxidantes y antioxidantes; También se estudiaron las pruebas de función renal. Hubo diferencias significativas entre el grupo de nefropatía por contraste (Grupo 2) y los grupos NAC y NAC+paricalcitol con respecto a los niveles séricos de urea y creatinina. Cuando se compararon los mismos grupos con respecto a los parámetros oxidantes (TOS-MDA) y antioxidantes (TAC-Paraoxonase), observamos que los parámetros oxidantes aumentaron en muestras de suero y tejido renal con el uso de NAC, y ese efecto se vio reforzado por la adición de paricalcitol a tratamiento NAC. Sin embargo, a pesar de una mayor eficacia antioxidante, no observamos una disminución en los niveles de urea y creatinina cuando se agregó paricalcitol para CI-AKI en ratas. No hubo diferencias significativas entre el Grupo 3 y el Grupo 4. El paricalcitol proporciona un efecto antioxidante más potente tanto en muestras de suero como de tejido renal cuando se agrega al tratamiento con NAC en ratas con CI-AKI. Sin embargo, a pesar del aumento de los parámetros antioxidantes, el paricalcitol no proporciona una disminución sig- nificativa en los niveles de urea y creatinina.

Paricalcitol attenuates indoxyl sulfate-induced apoptosis through the inhibition of MAPK, Akt, and NF-κB activation in HK-2 cells

BACKGROUND/AIMS: Indoxyl sulfate (IS) is a uremic toxin and an important causative factor in the progression of chronic kidney disease. Recently, paricalcitol (19-nor-1,25-dihydroxyvitamin D2) was shown to exhibit protective effects in kidney injury. Here, we investigated the effects of paricalcitol treatment on IS-induced renal tubular injury. METHODS: The fluorescent dye 2ʹ,7ʹ-dichlorofluorescein diacetate was used to measure intracellular reactive oxygen species (ROS) following IS administration in human renal proximal tubular epithelial (HK-2) cells. The effects of IS on cell viability were determined using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assays and levels of apoptosis-related proteins (Bcl-2-associated protein X [Bax] and B-cell lymphoma 2 [Bcl-2]), nuclear factor-κB (NF-κB) p65, and phosphorylation of mitogen-activated protein kinase (MAPK) and protein kinase B (Akt) were determined by semiquantitative immunoblotting. The promoter activity of NF-κB was measured by luciferase assays and apoptosis was determined by f low cytometry of cells stained with f luorescein isothiocyanate-conjugated Annexin V protein. RESULTS: IS treatment increased ROS production, decreased cell viability and induced apoptosis in HK-2 cells. IS treatment increased the expression of apoptosis-related protein Bax, decreased Bcl-2 expression, and activated phosphorylation of MAPK, NF-κB p65, and Akt. In contrast, paricalcitol treatment decreased Bax expression, increased Bcl-2 expression, and inhibited phosphorylation of MAPK, NF-κB p65, and Akt in HK-2 cells. NF-κB promoter activity was increased following IS, administration and was counteracted by pretreatment with paricalcitol. Additionally, flow cytometry analysis revealed that IS-induced apoptosis was attenuated by paricalcitol treatment, which resulted in decreased numbers of fluorescein isothiocyanate-conjugated Annexin V positive cells. CONCLUSIONS: Treatment with paricalcitol inhibited IS-induced apoptosis by regulating MAPK, NF-κB, and Akt signaling pathway in HK-2 cells.

Aplicación seriada de paricalcitol intranodular ¿Es eficaz en el tratamiento del hiperparatiroidismo secundario refractario? / Serial intranodular application of paricalcitol Is effective in the treatment of secondary refractory hyperparathyroidism?

Objetivo: determinar la eficacia del paricalcitol en la reducción de los niveles de PTH intacta (PTHi) al aplicarlo directamente en las glándulas paratiroides en pacientes con enfermedad renal crónica estadio 5 (ERC E5) en terapia dialítica con hiperparatiroidismo refractario e hiperplasia nodular. Material y métodos: pacientes con ERC E5 en terapia de diálisis e hiperparatiroidismo secundario refractario y en quienes por ecografía de cuello se detectó hiperplasia de más de una glándula paratiroides, caracterizada por un volumen mayor de 500 mm³. A cada paciente por guía ecográfica dirigida se le aplicó 0.5 cc (2.5 ugs) de paricalcitol (Zemplar®) en cada glándula hiperplásica independientemente de su tamaño, y según el grupo. En el grupo 1 (G1) recibieron paricalcitol semanal para un máximo de dos glándulas por sesión siempre del mismo lado y por un total de dos dosis por glándula; para el grupo 2 (G2) paricalcitol cada 15 días en esquema semejante al grupo 1 para un total de dos dosis por glándula y finalmente para el grupo 3 (G3) paricalcitol cada mes, pero en cada sesión se inyectaron todas las glándulas para un total de cuatro dosis por glándula. Diseño: estudio de intervención sin grupo control. Análisis estadístico: se evaluó si la intervención daba lugar a reducción significativa en los valores de PTHi, y las variables calcio, fósforo, calcio x fósforo y fosfatasa alcalina. Resultados: en el G1 (seis pacientes) se encontró una disminución estadísticamente significativaentre el nivel promedio de PTHi inicial y PTHi a los 30 días de iniciado el tratamiento (p=0.0077), pero no a los 51 ni 81 días. En el G2 (seis pacientes) al comparar la PTHi inicial, con el valor detectado a los 51, 75, 105 y 135 días posaplicación de la última dosis de paricalcitol, no hubo cambios significativos. En el G3 (cuatro pacientes)con relación a la PTHi inicial hubo reducción significativa en sus valores a los 60 días (p=0.012), 120 días (p=0.0099) y 180 días (p=0.00095), pero no a los 240 días (p=0.214049). En las demás variables (calcio, fósforo, calcio x fósforo, fosfatasa alcalina) no se detectaron cambios significativos en ningún grupo. No se presentaron complicaciones importantes. Conclusiones: en pacientes con ERC E5, en terapia de diálisis e hiperparatiroidismo secundario refractario, la administración de paricalcitol intranodular logra reducir significativamente los nivelesde PTHi, siempre y cuando se administre en grupos de dos glándulas con un intervalo de tiempo no superior a una semana, o por administración mensual simultanea de todas las glándulas. (Acta Med Colomb 2015; 40: 125-131).

Objective: go determine the effectiveness of paricalcitol in reducing the levels of intact PTH (iPTH) when applied directly on the parathyroid glands in patients with Grade 5 chronic kidney disease (CKD G5) with refractory hyperparathyroidism and nodular hyperplasia in dialysis therapy. Materials and methods: CKD G5 patients on dialysis therapy with refractory secondary hyperparathyroidism in whom through neck echography hyperplasia of more than one parathyroid gland characterized by a volume greater than 500 mm³ was detected. Through directed ultrasound guidance to each patient 0.5 cc (2.5ugs) of paricalcitol (Zemplar®) was applied in each hyperplasticgland regardless of size and according to the group. Group 1 (G1) received weekly paricalcitol for up to two glands per session always on the same side, for a total of two doses per gland; Group 2 (G2) received paricalcitol every 15 days in similar scheme as group 1 for a total of two doses per gland and finally for group 3 (G3) paricalcitol each month, but in every session all the glands were injected for a total four doses per gland. Design: intervention study with no control group. Statistical analysis: an assessment whether the intervention resulted in significant reduction in iPTH and variables calcium, phosphorus, calcium x phosphorus and alkaline phosphatase, was made. Results: In G1 (six patients), a statistically significant decrease between the average level of initial iPTH and iPTH at 30 days of starting treatment (p = 0.0077), but not at 51 or 81 days was found. In G2 (six patients) by comparing the initial iPTH, with the detected value at 51, 75, 105 and 135 days post-application of the last dose of paricalcitol, there were no significant changes. In G3 (four patients) relative to the initial iPTH there was significant reduction in their values at 60 days (p = 0.012), 120 days (p = 0.0099) and 180 days (p = 0.00095), but not at 240 days (p = 0.214049). On the other variables (calcium, phosphorus, calcium x phosphorus, alkaline phosphatase), no significant changes were detected in either group. No major complications occurred. Conclusions: in patients with CKD G5 in dialysis therapy and refractory secondary hyperparathyroidism, administration of intranodular paricalcitol achieves significantly lower levels of iPTH, as long as it is administered in groups of two glands with a time interval not exceeding one week, or by simultaneous monthly administration of all glands. (Acta Med Colomb 2015; 40:125-131).

Efficacy of paricalcitol on eGFR and proteinuria in non-dialysis CKD patients: a meta-analysis / 中华肾脏病杂志

Objective To systematic evaluate the efficacy of paricalcitol on estimated glomerular filtration rate (eGFR) and proteinuria in non-dialysis chronic kidney disease (CKD) patients.Methods According to the collaborative search strategy,PubMed,the clinical control test database of Cochrane Library,Embase,Chinese Wanfang database,CNKI,VIP database (form the date of database establishment to March 2014) were searched.Published and unpublished literature,abstracts in academic meetings (ASN,WCN,CSN) were also searched by hand.The randomized controlled trials (RCTs) about the efficacy paricalcitol on eGFR and proteinuria in non-dialysis CKD patients were selected.Review Manager Software 5.2 was used for statistical analysis.Results Seven RCTs with a total of 834 patients were included (508 in experimental group,326 in placebo group).No statistical difference of the efficacy on eGFR[SMD=-0.10,95％ CI:(-0.28-0.07),P=0.26] between lower dose paricalcitol (＜ 2 μg/d) group and placebo group,while higher dose (2 μg/d) group reduced eGFR significantly [SMD=-0.45,95％ CI:(-0.63--0.27),P ＜ 0.01].Compared with placebo,paricalcitol reduced proteinuria significantly [OR(95％C1):2.09(1.52-2.58),P ＜ 0.01],and there was no difference between different dose groups [OR(95％CI):1.09(0.62-1.91),P=0.77].Lower dose group [OR(95％C1):0.93(0.57-1.52),P=0.76] and higher dose group [OR(95％ CI):2.08(0.70-6.18),P=0.19] did not significantly increase the risk of adverse events.Conclusions Lower dose paricalcitol (＜ 2 μg/d)has no effect on eGFR in non-dialysis CKD patients meanwhile reduces proteinuria.The higher dose (2μg/d) may reduce eGFR without farther reduction in proteinuria.

Influence of paricalcitol on renal tubulointerstitial fibrosis in diabetic ne-phropathy / 中国病理生理杂志

[ ABSTRACT] AIM:To investigate the effect of paricalcitol ( P) on renal tubulointerstitial fibrosis and the under-lying mechanisms in diabetic nephropathy ( DN) .METHODS:DN rat model was induced by a single intraperitoneal in-jection of streptozotocin after fasting.The animals were randomly divided into 2 groups: the DN rats in paricalcitol-inter-vened group ( group P) were injected intraperitoneally with paricalcitol dissolved in propylene glycol after the day when the model was induced successfully at a dose of 0.4μg/kg (3 times a week);the DN rats in DN group ( group D) were given isopyknic propylene glycol.Normal control group ( group C) was also set up.The samples of blood, urine and renal tissue were collected after intervention of paricalcitol for 12 weeks.The biochemical indexes were measured.The renal tissues were used for pathologic observation and determining the expression of transforming growth factor-β1 (TGF-β1), Wnt-4,β-catenin and Klotho by immunohistochemistry and Western blotting.In addition, the correlation among the above indexes was analyzed.RESULTS:(1) Scr, BUN and 24 h urine protein increased significantly in group D compared with group C, while decreased in group P compared with group D ( P<0.05 ) .( 2 ) The area of renal tubulointerstitial fibrosis in-creased in group D compared with group C, while decreased in group P compared with group D (P<0.05).(3) The ex-pression of Klotho decreased, while the expression of TGF-β1, Wnt-4 and β-catenin increased in group D compared with group C (P<0.05).Compared with group D, the expression of Klotho increased, while the expression of TGF-β1, Wnt-4 andβ-catenin decreased in group P (P<0.05).(4) The expression of Klotho was negatively correlated with the fibrosis area, TGF-β1, Wnt-4 andβ-catenin (P<0.05).CONCLUSION:Paricalcitol inhibits renal tubulointerstitial fibrosis in DN by promoting the expression of renal Klotho, and inhibiting Wnt/β-catenin signaling pathway activation and TGF-β1 synthesis.

Antiapoptotic Effect of Paricalcitol in Gentamicin-induced Kidney Injury

While the anti-apoptotic effect of paricalcitol has been demonstrated in various animal models, it is not yet clear whether paricalcitol attenuates the apoptosis in gentamicin (GM)-induced kidney injury. We investigated the effect of paricalcitol on apoptotic pathways in rat kidneys damaged by GM. Rats were randomly divided into three groups: 1) Control group (n=8), where only vehicle was delivered, 2) GM group (n=10), where rats were treated with GM (150 mg/kg/day) for 7 days, 3) PARI group (n=10), where rats were co-treated with paricalcitol (0.2 microg/kg/day) and GM for 7 days. Paricalcitol attenuated renal dysfunction by GM administration in biochemical profiles. In terminal deoxynucleotidyl transferase dUTP nick end labeling staining, increased apoptosis was observed in GM group, which was reversed by paricalcitol co-treatment. Immunoblotting using protein samples from rat cortex/outer stripe of outer medulla showed increased Bax/Bcl-2 ratio and cleaved form of caspase-3 in GM group, both of which were reversed by paricalcitol. The phosphorylated Jun-N-terminal kinase (JNK) expression was increase in GM, which was counteracted by paricalcitol. The protein expression of p-Akt and nitro-tyrosine was also enhanced in GM-treated rats compared with control rats, which was reversed by paricalcitol co-treatment. Paricalcitol protects GM-induced renal injury by antiapoptotic mechanisms, including inhibition of intrinsic apoptosis pathway and JNK.

Impact of paricalcitol on proteinuria in diabetic nephropathy rats / 中华肾脏病杂志

ObjectiveTo study the effect of 1,25-(OH)2D3 analogs paricalcitol on proteinuriaindiabeticnephropathy (DN)rats, andtoinvestigateitspossiblemechanism.Methods DN model rats were established by intraperitoneal injection with streptozotocin.All the DN rats were randomly divided into the paricalcitol group(group P ) and DN group(group D).Healthy rats were chosen as healthy control group(group N).24-h urinary protein and serum biochemical indicators were examined after 12 weeks.ELISA was applied to detect the level of renin and Ang Ⅱ in the kidney.Immunohistochemistry and real-time PCR were used to detect the protein and mRNA expression of heparanases(HPA)and podoein.Results Compared with group N,24-h urinary protein,serum creatinine,renin and Ang Ⅱ in group D and group P were markedly increased,and they were significantly higher in group D as compared to group P (all P＜0.05).Compared with group N,the expression of HPA protein and mRNA in group D and group P increased markedly,and higher expression was found in group D(all P＜0.05).The expression of podocin protein and mRNA in group D and group P decreased markedly,and lower expression was found in group D(all P＜0.05).Renin level was positively correlated with HPA protein expression (r=0.78,P＜O.OS),negatively correlated with podocin protein expression(r=-0.63,P＜O.05),and not correlated with their mRNA expression.Conclusion Paricalcitol can significantly reduce the proteinuria,which may be associated with the inhibition of renin by down-regulating protein expression of HPAin glomerular basement membrane and up-regulating protein expression of podocin in podocyte.

Cardiorenal syndrome and vitamin D receptor activation in chronic kidney disease

Cardiorenal syndrome (CRS) refers to a constellation of conditions whereby heart and kidney diseases are pathophysiologically connected. For clinical purposes, it would be more appropriate to emphasize the pathophysiological pathways to classify CRS into: (1) hemodynamic, (2) atherosclerotic, (3) uremic, (4) neurohumoral, (5) anemic??hematologic, (6) inflammatory-oxidative, (7) vitamin D receptor (VDR) and/or FGF23-, and (8) multifactorial CRS. In recent years, there have been a preponderance data indicating that vitamin D and VDR play an important role in the combination of renal and cardiac diseases. This review focuses on some important findings about VDR activation and its role in CRS, which exists frequently in chronic kidney disease patients and is a main cause of morbidity and mortality. Pathophysiological pathways related to suboptimal or defective VDR activation may play a role in causing or aggravating CRS. VDR activation using newer agents including vitamin D mimetics (such as paricalcitol and maxacalcitol) are promising agents, which may be related to their selectivity in activating VDR by means of attracting different post-D-complex cofactors. Some, but not all, studies have confirmed the survival advantages of D-mimetics as compared to non-selective VDR activators. Higher doses of D-mimetic per unit of parathyroid hormone (paricalcitol to parathyroid hormone ratio) is associated with greater survival, and the survival advantages of African American dialysis patients could be explained by higher doses of paricalcitol (>10 microg/week). More studies are needed to verify these data and to explore additional avenues for CRS management via modulating VDR pathway.

Suppressive Effect of 19-nor-1alpha-25-Dihydroxyvitamin D2 on Gastric Cancer Cells and Peritoneal Metastasis Model

The active metabolite of vitamin D, 1,25-dihydroxyvitamin D3 (calcitriol), inhibits the growth of several types of human cancer cells in vitro, but its therapeutic use is limited because it causes hypercalcemia. Among its analogs, 19-nor-1,25-dihydroxyvitamin D2 (paricalcitol), has fewer calcemic effects and exhibits an activity equipotent to that of calcitriol. We assessed the antitumor and anti-inflammatory effects of paricalcitol in gastric cancer cells, and evaluated the potential role of vitamin D in the treatment of peritoneal metastatic gastric cancer. In this study, treatment with paricalcitol inhibited gastric cancer cell growth and induced cell cycle arrest. Paricalcitol also induced apoptosis and showed anti-inflammatory activity. Moreover, the growth of intraperitoneal metastases in vivo was reduced in mice treated with paricalcitol. 18F-FDG uptake was significantly lower in the paricalcitol group compared to control group (SUV; control group 13.2 +/- 5.3 vs paricalcitol group 4.5 +/- 3.0). Intraperitoneal tumor volume was significantly lower in paricalcitol treated mice (control group 353.2 +/- 22.9 mm3 vs paricalcitol group 252.0 +/- 8.4 mm3). These results suggest that the vitamin D analog, paricalcitol, has anticancer activity on gastric cancer cells by regulation of the cell cycle, apoptosis, and inflammation.

Intraperitoneal Paricalcitol Treatment for Secondary Hyperparathyroidism in CAPD patient: A Case Report / 대한신장학회지

Secondary hyperparathyroidism is a major complication in ESRD patients undergoing dialysis. In hemodialysis patients with secondary hyperparathyroidism, intravenous administration of paricalcitol became widely utilized. In CAPD patients, however, the intravenous administration of paricalcitol which requires frequent visits to the clinic is not practical. The subject of this study was one CAPD patient with secondary hyperparathyroidism. He had already received oral calcitriol pulse therapy for 6 months and thereafter refused parathyroidectomy and intravenous paricalcitol which required frequent visits to the hospital. Furthermore, paricalcitol capsule is not yet introduced in Korea. Consequently, intraperitoneal paricalcitol therapy was tried whereby the patient was taught how to inject the paricalcitol (5 ug) directly into the dialysate for three times per week before bedtime. Blood samples for measurement of intact parathyroid hormone (iPTH), serum ionized calcium, serum phosphate, serum total alkaline phosphatase levels were obtained at baseline and after 1, 2, 3 and 4 months of treatment. After usage of intraperitoneal paricalcitol for 2 months, there was a significant decrease in iPTH level. In conclusion, intraperitoneal paricalcitol therapy might be effective for suppressing iPTH in CAPD patients with secondary hyperparathyroidism. A large-scale and long-term study must be conducted for safety and clinical effect.