A rare genomic duplication in 2p14 underlies autosomal dominant hearing loss DFNA58.

Here we define a ~200 Kb genomic duplication in 2p14 as the genetic signature that segregates with postlingual progressive sensorineural autosomal dominant hearing loss (HL) in 20 affected individuals from the DFNA58 family, first reported in 2009. The duplication includes two entire genes, PLEK and CNRIP1, and the first exon of PPP3R1 (protein coding), in addition to four uncharacterized long non-coding (lnc) RNA genes and part of a novel protein-coding gene. Quantitative analysis of mRNA expression in blood samples revealed selective overexpression of CNRIP1 and of two lncRNA genes (LOC107985892 and LOC102724389) in all affected members tested, but not in unaffected ones. Qualitative analysis of mRNA expression identified also fusion transcripts involving parts of PPP3R1, CNRIP1 and an intergenic region between PLEK and CNRIP1, in the blood of all carriers of the duplication, but were heterogeneous in nature. By in situ hybridization and immunofluorescence, we showed that Cnrip1, Plek and Ppp3r1 genes are all expressed in the adult mouse cochlea including the spiral ganglion neurons, suggesting changes in expression levels of these genes in the hearing organ could underlie the DFNA58 form of deafness. Our study highlights the value of studying rare genomic events leading to HL, such as copy number variations. Further studies will be required to determine which of these genes, either coding proteins or non-coding RNAs, is or are responsible for DFNA58 HL.

The elevated serum levels of calcineurin and nuclear factor of activated T-cells 1 in children with Kawasaki disease.

BACKGROUND: The calcineurin and nuclear factor of activated T-cells (CaN-NFAT) signaling pathway had been found to be associated with Kawasaki disease (KD) susceptibility and coronary artery aneurysm formation as a contributor. To evaluate serum calcineurin (CaN) and nuclear factor of activated T-cells 1(NFAT1) levels in patients with Kawasaki disease (KD). METHODS: Serum levels of CaN and NFAT1 were measured by enzyme-linked immunosorbent assay method in 66 healthy children and 74 KD patients at acute, afebrile and subacute stage. RESULTS: The serum levels of CaN and NFAT1 increased significantly in the acute stage, and decreased progressively in the afebrile and subacute stage, along with the reduction of C-reactive protein, white blood cells and neutrophil counts. And in the acute stage, the afebrile stage and the subacute stage, the expression of CaN and NFAT1 was upregulated significantly in KD patients compared to that in the healthy control. After the IVIG treatment, the serum levels of CaN and NFAT1 declined significantly in IVIG responders. However, the CaN and NTAT1 levels in the IVIG non-responders declined slowly. And in the afebrile stage, the NFAT1 levels were lower in KD patients with coronary artery lesions (CALs) (268.82 ± 11.96 ng/ml) than those without CALs (285.84 ± 25.13 ng/ml). However, the serum levels of CaN in KD patients with CALs had no significant difference with those in KD patients without CALs. CONCLUSIONS: The specific regulation of CaN and NFAT1 serum levels in the course of KD was suggested that both of them were related in the development of KD.

Calcineurin B1 subunit in human peripheral blood mononuclear cells and its role in idiopathic membranous nephropathy.

The immune responses involved in the pathogenesis of idiopathic membranous nephropathy (IMN) have not been fully understood. Calcineurin, a key signaling enzyme in T-cell activation, may be implicated in IMN. The present study aimed to investigate the role of calcineurin B1 subunit (CnB1) in IMN and the potential mechanism.A total of 59 biopsy-proven IMN patients and 28 healthy controls were recruited. The CnB1 expression in human peripheral blood mononuclear cells (PBMCs) was assessed by Western blotting. Knockdown and overexpression of CnB1 in Jurkat T cell line were achieved by small interference RNA (siRNA) transfection and lentiviral transduction, respectively.It was found that PBMCs CnB1 expression was significantly increased in IMN patients (P = .002), but unrelated to the severity and prognosis of IMN. Knockdown of CnB1 in Jurkat cells inhibited the nuclear factor of activated T cells (NFAT)-regulated gene expression required for T-cell activation.Our study suggested the potential role of CnB1 in the occurrence of IMN. The mechanism maybe involved the effect of CnB1 on the T-cell activation mediated by calcineurin-NFAT signaling.

Correlation between Serum Calcineurin Activity and Left Ventricular Hypertrophy in Hypertensive Patients and Its Clinical Significance.

OBJECTIVE: The aim of this study is to investigate the correlation between calcineurin (CaN) and hypertension with left ventricular hypertrophy (HLVH) and to evaluate its potential clinical significance. DESIGN: The study involved 160 patients diagnosed with hypertension and 42 controls. Based on the exclusion criteria, 42 were not eligible for this study. The remaining 118 hypertensive patients were categorized into 2 subgroups based on left ventricular mass index and relative ventricular wall thickness: a normal model subgroup with hypertension (HNM) and an HLVH subgroup. Serum CaN levels were determined by enzyme-linked immunosorbent assay, while serum CaN activity was determined by malachite green colorimetric assay. RESULTS: Among the HNM and HLVH subgroups, a positive correlation was demonstrated between serum CaN activity, but not serum CaN level, and HLVH. Moreover, the HLVH subgroup displayed a remarkable increase in the levels of brain natriuretic peptide, cystatin C, urinary albumin/creatinine ratio, and left atrium diameter compared to the HNM subgroup and controls. CONCLUSION: There was a positive correlation between serum CaN activity and LVH in hypertensive patients. Activated CaN could play an important role in the pathophysiologic mechanism of HLVH. Serum CaN activity could be a clinically useful diagnostic and prognostic biomarker for LVH.

Activity of the Calcineurin Pathway in Patients on the Liver Transplantation Waiting List: Factors of Variability and Response to Tacrolimus Inhibition.

BACKGROUND: We sought to evaluate, in patients on a liver transplantation waiting list, potential biomarkers of the base calcineurin pathway activity with use of a new model of nonstimulated peripheral blood mononuclear cells (PBMC) and ex vivo response to tacrolimus (TAC). METHODS: The calcineurin pathway activity was explored ex vivo in stimulated and nonstimulated PBMC from 19 patients. The inhibition of NFAT1 translocation to PBMC nuclei, expression of intracellular IL-2, and membrane CD25 in different T-cell subsets were measured by multiparametric flow cytometry before and after exposure to TAC. We also studied the influence on the individual response of polymorphisms in 3 key genes of the calcineurin pathway: PPIA, PPP3CA, and IL2RA. RESULTS: All pharmacodynamics profiles closely fitted an I/Imax sigmoid model. Interindividual variability was higher in nonstimulated than in stimulated conditions, as well as in the presence of TAC. IL-2+CD8+ cells at TAC Imax showed the highest interindividual variability, suggesting its usefulness as a biomarker of individual TAC effects integrating many different sources of regulation and variability. Moreover, in the absence of TAC, patients with end-stage liver disease exhibited lower NFAT1 translocation and T-cell activation than healthy volunteers from a previous study under similar conditions. Multivariate statistical analysis showed strong and significant associations between TAC pharmacodynamic parameters and 2 polymorphisms in the gene-coding cyclophilin A (rs8177826 and rs6850). CONCLUSIONS: We show the feasibility of using nonstimulated PBMCs to explore the calcineurin pathway under more physiologic conditions and point toward potential biomarkers for TAC pharmacodynamic monitoring. ClinicalTrials.gov Identifier: NCT01760356.

Association of CnB 5I/5D promoter gene polymorphism and serum calcineurin levels in early onset of coronary artery disease of south Indian cohort.

Calcineurin, a serine/threonine phosphatase is a calcium dependent protein which on activation triggers transcriptional up regulation of inflammatory genes associated with inflammation in the arteries and progressive formation of plaques in CAD. The present investigation is aimed to study the possible association of Calcineurin encoding gene PPP3R1 (CnB 5I/5D) polymorphism in correlation with serum levels of calcineurin in coronary artery disease (CAD). A total of 300 angiographically documented CAD patients and 300 age, gender ethnicity matched healthy controls were recruited for the study. Serum Calcineurin levels were estimated by enzyme-linked immunosorbent assay (ELISA) and genotypes were determined based on PCR-RFLP. The CnB 5I/5D variation was found to be significantly associated with CAD (p<0.03), correlated to elevated serum calcineurin levels encoded by (<0.01) 5I/5D allele authenticated by Insilco analysis. Multiple logistic regression analysis also confirmed these findings [adjusted OR for DD genotype was 3.19 (95% CI 1.40-7.24) and p=0.001]. The results suggest that 5-base pair deletion results in increased serum calcineurin levels and may trigger up regulation of calcineurin which mediates vascular inflammation and atherosclerosis in CAD.

Endoplasmic Reticulum Stress Predicts Clinical Response to Cyclosporine Treatment in Primary Membranous Nephropathy.

BACKGROUND: Little is known about the endoplasmic reticulum stress (ERS) marker glucose regulated protein 78 (GRP78) and calcineurin in the kidney in primary membranous nephropathy (PMN) and if they could predict post-cyclosporine treatment outcome. METHODS: This is a retrospective study using a dataset of biopsy-confirmed PMN from Peking Union Medical College Hospital from 1996 to 2014. Seventy-six adult patients treated with cyclosporine as primary immunosuppression for at least 6 months were studied. Immunohistochemistry was used to detect GRP78 and calcineurin in the kidney. Serum calcineurin was assayed by ELISA. Patients were grouped into no-remission (NR, n = 17), partial remission (PR, n = 39), or complete remission (CR, n = 20) at the end of 6 months of treatment. RESULTS: There was no difference of initial dose of cyclosporine among NR, PR, and CR groups. Kidney calcineurin expression in PMN was significantly increased compared to that in controls (p < 0.0083). The glomerular GRP78 in NR PMN was higher than that in control, CR and PR patients (p < 0.0083). Kidney calcineurin expression and GRP78 expression was positively correlated. However, there were no differences in either serum calcineurin levels or kidney calcineurin expressions among NR, PR or CR groups. There was a negative correlation between serum calcineurin activity and whole kidney calcineurin expression (p = 0.034) or glomerular calcineurin expression (p = 0.007). Neither kidney calcineurin nor GRP78 expression was correlated with proteinuria. CONCLUSIONS: ERS marker GRP78 in the glomeruli but not serum or kidney calcineurin expression could be a useful marker in PMN to negatively predict the response to cyclosporine treatment at the sixth month.

Cissampelos pareira Linn. ameliorates thyroxin-induced cardiac hypertrophy in rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Cissampelos pareira extract has been traditionally used in ayruveda as cardiotonic, diuretics and in heart complains but its pharmacological evaluation in thyroxin-induced cardiac hypertrophy has not yet been explored. AIM OF THE STUDY: The aim of this study was to assess the cardioprotective effect of C. pareira root extract in experimentally induced hyperthyroidism in rats. MATERIALS AND METHODS: Male Wistar rats were treated with (i) thyroxin (0.1 mg/kg/day, i.p.) for 30 days, (ii) C. pareira extract (200 mg/kg/day, p.o.) alone for 60 days, (iii) C. pareira extract (100 and 200 mg/kg/day, p.o., respectively) for 30 days then with thyroxin for another 30 days, (iv) thyroxin for 30 days then C. pareira extract (100 and 200 mg/kg/day, p.o., respectively) for another 30 days. At the end of experiment, serum calcineurin, nitric oxide, lactate dehydrogenase, and thiobarbituric acid reactive substance as well as serum and/or myocardial antioxidant enzymes activity were estimated. RESULTS: Hyperthyroid induced cardiotoxicity was characterized by a significant (P<0.001) increase in heart weight/body weight ratio, serum calcineurin, nitric oxide, lactate dehydrogenase and thiobarbituric acid reactive substance levels as well as a significant decrease in serum reduced glutathione, myocardial glutathione peroxidase, glutathione reductase and glutathione-S-transferase levels, which were significantly (P<0.05 and P<0.01) reverted by C. pareira extract treatment. Reversal of histological changes on treatment with C. pareira extract was also supported the biochemical parameters. These results were quite comparable with amlodipine, the standard drug taken in this study. CONCLUSIONS: Treatment with C. pareira extract ameliorates thyroxin-induced oxidative stress and cardiac hypertrophy, probably through amelioration of calcineurin activity and augmentation of antioxidant enzyme activities.

Population PKPD of voclosporin in renal allograft patients.

The aims of this population-pharmacokinetic/pharmacodynamic (POP-PKPD) analysis of voclosporin in renal allograft patients were to build a POP-PKPD model for voclosporin and calcineurin activity (CNa) and identify clinically relevant covariates that could assist dosing of the drug. POP-PKPD modeling was performed using a stochastic approximation of the standard expectation maximization (SAEM) algorithm for nonlinear mixed-effects as implemented in Monolix™ 3.2. Voclosporin whole blood concentrations were obtained from de novo renal allograft patients and assayed using a validated LC/MS/MS assay. CNa was measured using a (32)P-radiolabeled assay. A two-compartment model with simultaneous sigmoid inhibitory Emax model was used to describe the PKPD relationship between voclosporin concentration and CNa. The POP-PKPD model was then utilized to simulate an optimal initial dosing strategy. Eighty-seven patients were included in the POP-PKPD study. Population mean estimates (relative standard error, rse) for oral clearance (CL/F) and first compartment volume of distribution (V1), were 717 mL min(-1) (35%) and 2010 mL (17%), respectively. Maximum CNa Inhibition (Imax), effective concentration (C50), and baseline immunosuppression (S0) were 0.87 pmol/min/mg (8.0%), 123 ng/mL (10%), and 1.15 pmol/min/mg (4.0%), respectively. Covariate analyses demonstrated that age and body surface area significantly influenced CL/F: CLi=717(Agei/48.8)-0.57(BSAi/1.99)1.1, while serum triglycerides significantly altered S0: S0i=1.15(TRIGi/1.97)0.15.

Calcineurin activity assay measurement by liquid chromatography-tandem mass spectrometry in the multiple reaction monitoring mode.

BACKGROUND: Blood concentrations of the calcineurin inhibitors (CNIs) cyclosporine and tacrolimus are currently measured to monitor immunosuppression in transplant patients. The measurement of calcineurin (CN) phosphatase activity has been proposed as a complementary pharmacodynamic approach. However, determining CN activity with current methods is not practical. We developed a new method amenable to routine use. METHODS: Using liquid chromatography-multiple reaction monitoring mass spectrometry (LC-MRM-MS), we quantified CN activity by measuring the dephosphorylation of a synthetic phosphopeptide substrate. A stable isotope analog of the product peptide served as internal standard, and a novel inhibitor cocktail minimized dephosphorylation by other major serine/threonine phosphatases. The assay was used to determine CN activity in peripheral blood mononuclear cells (PBMCs) isolated from 20 CNI-treated kidney transplant patients and 9 healthy volunteers. RESULTS: Linearity was observed from 0.16 to 2.5 µmol/L of product peptide, with accuracy in the 15% tolerance range. Intraassay and interassay recoveries were 100.6 (9.6) and 100 (7.5), respectively. Michaelis-Menten kinetics for purified CN were Km = 10.7 (1.6) µmol/L, Vmax = 2.8 (0.3) µmol/min · mg, and for Jurkat lysate, Km = 182.2 (118.0) µmol/L, Vmax = 0.013 (0.006) µmol/min · mg. PBMC CN activity was successfully measured in a single tube with an inhibitor cocktail. CONCLUSIONS: Because LC-MRM-MS is commonly used in routine clinical dosage of drugs, this CN activity assay could be applied, with parallel blood drug concentration monitoring, to a large panel of patients to reevaluate the validity of PBMC CN activity monitoring.

Expression of calcineurin activity after lung transplantation: a 2-year follow-up.

The objective of this pharmacodynamic study was to longitudinally assess the activity of calcineurin during the first 2 years after lung transplantation. From March 2004 to October 2008, 107 patients were prospectively enrolled and their follow-up was performed until 2009. Calcineurin activity was measured in peripheral blood mononuclear cells. We report that calcineurin activity was linked to both acute and chronic rejection. An optimal activity for calcineurin with two thresholds was defined, and we found that the risk of rejection was higher when the enzyme activity was above the upper threshold of 102 pmol/mg/min or below the lower threshold of 12 pmol/mg/min. In addition, we report that the occurrence of malignancies and viral infections was significantly higher in patients displaying very low levels of calcineurin activity. Taken together, these findings suggest that the measurement of calcineurin activity may provide useful information for the management of the prevention therapy of patients receiving lung transplantation.

Effect of Cissampelos pareira root extract on isoproterenol-induced cardiac dysfunction.

The aim of this study was to assess the cardioprotective effect of Cissampelos pareira root extract on isoproterenol-induced cardiac dysfunction in rats. Male albino Wistar rats were randomly divided into eight groups and received either normal saline (0.5 ml/kg, intraperitoneally), isoproterenol (5 mg/kg, intraperitoneally), C. pareira (100 and 200 mg/kg, by gavage, respectively) alone, amlodipine (9 mg/kg, by gavage) alone, C. pareira (100 and 200 mg/kg, respectively) + isoproterenol and amlodipine (9 mg/kg) + isoproterenol, once a day for 30 days, respectively. Isoproterenol-induced cardiac dysfunction was characterized by a significant (P < 0.001) increase in the heart weigh/body weight ratio, serum calcineurin, nitric oxide, lactate dehydrogenase, and thiobarbituric acid reactive substance levels, as well as a significant decrease in serum-reduced glutathione, cardiac glutathione peroxidase, glutathione reductase, and glutathione-S-transferase levels, which were significantly (P < 0.05 and P < 0.01) improved by C. pareira treatment. No significant alteration was observed in the group treated with C. pareira alone compared with the control. C. pareira treatment also restored histopathological changes observed in isoproterenol-induced rats. Amlodipine is used as standard drug in this study. Thus, these results suggest that the attenuation of isoproterenol-induced cardiac dysfunction by treatment with ethanolic root extract of C. pareira may be due to amelioration of calcineurin activity and free radical formation, and by augmentation of antioxidant enzymes activities.

Significance of trough monitoring for tacrolimus blood concentration and calcineurin activity in adult patients undergoing primary living-donor liver transplantation.

PURPOSE: Tacrolimus pharmacokinetics and calcineurin activity in peripheral blood mononuclear cells (PBMCs) were investigated in adult patients undergoing primary living-donor liver transplantation (LDLT) in order to clarify the significance of monitoring the tacrolimus blood trough concentration during the early post-transplantation period. METHODS: Fourteen patients were enrolled in this study, and time-course data following the oral administration of a conventional tacrolimus formulation twice daily were obtained at 1 and 3 weeks post-transplantation. The concentration of tacrolimus in whole blood and calcineurin activity in PBMCs were measured. RESULTS: The apparent clearance of tacrolimus significantly increased at 3 weeks versus 1 week post-transplantation, although the trough concentration did not significantly differ at these time points. The concentration at each sampling time, except at 1 h post-dose, correlated well with the area under the concentration-time curve from 0 to 12 h (AUC(0-12)). Neither the concentration at the trough time point nor AUC(0-12) was correlated with the area under the calcineurin activity-time curve from 0 to 12 h; however, calcineurin activity at the trough time point was strongly correlated with the latter (r (2) > 0.92). CONCLUSIONS: Based on these results, trough concentration monitoring can be considered an appropriate procedure for routine tacrolimus dosage adjustment in adult LDLT patients. Monitoring of calcineurin activity at the trough time point was also found to be potentially useful for predicting the immunological status of the patient during the tacrolimus dosing interval.

Calcineurin inhibitors acutely improve insulin sensitivity without affecting insulin secretion in healthy human volunteers.

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT: New onset diabetes after transplantation is related to treatment with immunosuppressive medications. Clinical studies have shown that risk of new onset diabetes is greater with tacrolimus compared with ciclosporin. The diabetogenicity of ciclosporin and tacrolimus has been attributed to both beta cell dysfunction and impaired insulin sensitivity. WHAT THIS STUDY ADDS: This is the first trial to investigate beta cell function and insulin sensitivity using gold standard methodology in healthy human volunteers treated with clinically relevant doses of ciclosporin and tacrolimus. We document that both drugs acutely increase insulin sensitivity, while first phase and pulsatile insulin secretion remain unaffected. This study demonstrates that ciclosporin and tacrolimus have similar acute effects on glucose metabolism in healthy humans. AIM The introduction of calcineurin inhibitors (CNIs) ciclosporin (CsA) and tacrolimus (Tac) has improved the outcome of organ transplants, but complications such as new onset diabetes mellitus after transplantation (NODAT) cause impairment of survival rates. The relative contribution of each CNI to the pathogenesis and development of NODAT remains unclear. We sought to compare the impact of CsA and Tac on glucose metabolism in human subjects. METHODS: Ten healthy men underwent 5 h infusions of CsA, Tac and saline in a randomized, double-blind, crossover study. During infusion glucose metabolism was investigated using following methods: a hyperinsulinaemic-euglycemic clamp, an intravenous glucose tolerance test (i.v.GTT), glucose-stimulated insulin concentration-time series and indirect calorimetry. RESULTS: Clamp derived insulin sensitivity was increased by 25% during CsA (P < 0.0001) and 13% during Tac administration (P = 0.047), whereas first phase and pulsatile insulin secretion were unaffected. Coinciding with the CNI induced improved insulin sensitivity, glucose oxidation rates increased, while insulin clearance rates decreased, only non-significantly. Tac singularly lowered hsCRP concentrations, otherwise no changes were observed in circulating glucagon, FFA or adiponectin concentrations. Mean blood concentrations of CNIs were 486.9 ± 23.5 µg l(-1) for CsA and 12.8 ± 0.5 µg l(-1) for Tac. CONCLUSIONS: Acute effects of i.v. CsA, and to a lesser degree Tac infusions, in healthy volunteers include increased insulin sensitivity, without any effect on first phase or pulsatile insulin secretion.

Chronic psychosocial stress enhances long-term depression in a subthreshold amyloid-beta rat model of Alzheimer's disease.

In addition to genetic aspects, environmental factors such as stress may also play a critical role in the etiology of the late onset, sporadic Alzheimer's disease (AD). The present study examined the effect of chronic psychosocial stress in a sub-threshold Aß (subAß) rat model of AD on long-term depression by two techniques: electrophysiological recordings of synaptic plasticity in anesthetized rats, and immunoblot analysis of memory- and AD-related signaling molecules. Chronic psychosocial stress was induced using a rat intruder model. The subAß rat model of AD, which was intended to represent outwardly normal individuals with a pre-disposition to AD, was induced by continuous infusion of 160 pmol/day Aß1₋42 via a 14-day i.c.v. osmotic pump. Results from electrophysiological recordings showed that long-term depression evoked in stress/subAß animals was significantly enhanced compared with that in animals exposed to stress or subAß infusion alone. Molecular analysis of various signaling molecules 1 h after induction of long-term depression revealed an increase in the levels of calcineurin and phosphorylated CaMKII in groups exposed to stress compared with other groups. The levels of the brain-derived neurotrophic factor (BDNF) were significantly decreased in stress/subAß animals but not in stress or subAß animals. In addition, the levels of beta-site amyloid precursor protein cleaving enzyme were markedly increased in stress/subAß. These findings suggest that chronic stress may accelerate the impairment of synaptic plasticity and consequently cognition in individuals 'at-risk' for AD.

Isoproterenol-induced cardiomyopathy in rats: influence of Acorus calamus Linn.: A. calamus attenuates cardiomyopathy.

Acorus calamus has been used as a traditional remedy since ancient days but its cardioprotective effect is not yet well characterized. The aim of this study was to assess the effect of A. calamus rhizome extract in isoproterenol-induced cardiomyopathy in rats. Male Wistar rats were treated with normal saline (0.5 ml/kg, i.p.), isoproterenol (5 mg/kg, i.p.), A. calamus (100 and 200 mg/kg, respectively, by gavage) alone, amlodipine (9.0 mg/kg, by gavage) alone, A. calamus (100 and 200 mg/kg, respectively) + isoproterenol and amlodipine (9.0 mg/kg) + isoproterenol, single dose/day for 30 days, respectively. Isoproterenol-induced cardiomyopathy was characterized by a significant (P < 0.001) increase in heart weigh/body weight ratio, calcineurin, nitric oxide, lactate dehydrogenase, and thiobarbituric acid-reactive substance levels as well as a significant (P < 0.001) decrease in reduced glutathione, glutathione peroxidase, glutathione reductase, and glutathione-S-transferase levels. Treatment with A. calamus significantly (P < 0.05 and P < 0.01) attenuated isoproterenol-induced cardiomyopathy. No significant alteration was found in A. calamus-alone groups compared with the vehicle. Amlodipine is used as standard drug in this study. Thus, the result shows that A. calamus attenuates isoproterenol-induced cardiomyopathy. This could be due to attenuating calcineurin activity and oxidative stress.

Corticosteroid elimination in simultaneous liver-kidney transplantation recipients.

BACKGROUND: Simultaneous liver-kidney transplantation (SLK) has more than doubled since 2002. While less common in kidney transplant alone recipients (KTA), corticosteroid discontinuation is performed routinely in liver transplantation, raising the question of optimal immunosuppression for SLK recipients. METHODS: A retrospective case series of 16 SLK recipients under a steroid withdrawal protocol was performed to compare short-term outcomes to a contemporaneous cohort of 32 KTA recipients. RESULTS: In 69% of SLK recipients, corticosteroids were eliminated compared to 3% of KTA recipients, p < 0.0001. When comparing SLK and KTA recipients one yr post-transplant, there were no significant differences in renal graft rejection (23.1% vs. 6.3%), death-censored renal graft survival (100% vs. 97%), estimated glomerular filtration rate (74.4 vs. 62.6 mL/min), serum creatinine (1.10 vs. 1.39 mg/dL), or maintenance immunosuppression, respectively. CONCLUSIONS: Corticosteroids may be withdrawn safely in SLK recipients with one-yr renal outcomes comparable to a KTA cohort.

Deficiency in calcineurin activity in liver transplantation candidates with alcoholic cirrhosis or hepatocellular carcinoma.

BACKGROUND: Tacrolimus and cyclosporin inhibits the activity of calcineurin, a serine/threonine phosphatase that is involved in many physiological and pathological pathways. However, the baseline calcineurin phosphatase activity (CPA) measured before the transplant is unknown. In this study, we determine baseline CPA in liver transplant (LT) candidates and explore some factors that might modify it. PATIENTS AND METHODS: Thirty-two consecutive LT candidates (25 men, seven women, average age 53.4 years) were included. Seven millilitres of whole blood was collected from each patient. CPA was determined in lymphocytes quantifying a dephosphorylated peptide phosphorylated previously (D-L-D-V-P-I-P-G-R-F-D-R-R-V-S-V-A-A-E) by high-performance liquid chromatography. The relationship between CPA and the quantitative variables was tested according to Pearson's correlation. A two-way analysis of variance was performed to test the independent role of categorical parameters in CPA. RESULTS: The median CPA was significantly lower in LT candidates than in healthy volunteers [179.2 (146.9-226.3) vs 247.8 (220.9-292.5) pmol/min/10(6) peripheral blood mononuclear cell (PBMC), respectively, P=0.0002]. CPA was also significantly lower in alcoholic cirrhosis (152.2 vs 211.1 pmol/min/10(6) PBMC, P=0.04) and in the presence of hepatocellular carcinoma (HCC) (152.0 vs 213.5 pmol/min/10(6) PBMC, P=0.0074) compared with other liver diseases. A two-way analysis of variance showed that these parameters were independently associated with lower CPA (P=0.05 for alcohol and P=0.0056 for HCC respectively). CONCLUSION: This pilot study showed a lower CPA in patients with AC and HCC. This phenomenon may contribute towards lowering the risk of acute rejection in these patients after LT and, on the other hand, may increase the risk of de novo cancers.

Drug interaction between voriconazole and calcineurin inhibitors in allogeneic hematopoietic stem cell transplant recipients.

Although voriconazole has been shown to interact with calcineurin inhibitors, this interaction has not been thoroughly examined. The purpose of this study was to evaluate the drug interaction between voriconazole and calcineurin inhibitors among recipients of allogeneic hematopoietic stem cell transplantation (HSCT). Twenty-one recipients of allogeneic HSCT were evaluated. Those recipients had been on CsA (n=10) or tacrolimus (n=11) when voriconazole (400 mg per day orally, or 8 mg/kg per day, i.v.) was initiated. Trough concentrations of calcineurin inhibitors were measured before and periodically after initiating voriconazole to determine the concentration/dose (C/D) ratio of calcineurin inhibitors. Median C/D ratio significantly increased by initiating voriconazole: from 86.0 (range, 43.5-178.8) to 120.2 (range, 86.1-379.4) in CsA (P<0.05), and from 595.9 (range, 51.3-1643.3) to 890.7 (range, 94.1-4658.3) (ng/ml)/(mg/kg) in tacrolimus (P<0.01). Median increases in the C/D ratio did not differ significantly between CsA and tacrolimus (82.1%, ranging from -9.4 to 266.9% vs 115.6%, ranging from 25.4 to 307.6%). These results indicate that voriconazole alters the blood concentration of calcineurin inhibitors with a wide range of interindividual variability after allogeneic HSCT. Dose adjustment of calcineurin inhibitors on initiating voriconazole should not be decided uniformly, but determined on an individual basis by close monitoring of their blood concentrations.