Cyclosporin and organ specific toxicity: clinical aspects, pharmacogenetics and perspectives

Cyclosporin-induced hypertension is associated with the up-regulation of Na+-K+-2Cl- cotransporter (NKCC2)

BACKGROUND

The use of cyclosporin A (CsA) is hampered by the development of nephrotoxicity including hypertension, which is partially dependent on renal sodium retention. To address this issue, we have investigated in vivo sodium reabsorption in different nephron segments of CsA-treated rats through micropuncture study coupled to expression analyses of sodium transporters. To translate the findings in rats to human, kidney-transplanted patients having CsA treatment were enrolled in the study.

METHODS

Adult male Sprague-Dawley rats were treated with CsA (15 mg/kg/day) for 21 days, followed by micropuncture study and expression analyses of sodium transporters. CsA-treated kidney-transplanted patients with resistant hypertension were challenged with 50 mg furosemide.

RESULTS

CsA-treated rats developed hypertension associated with reduced glomerular filtration rate. In vivo microperfusion study demonstrated a significant decrease in rate of absolute fluid reabsorption in the proximal tubule but enhanced sodium reabsorption in the thick ascending limb of Henle's loop (TAL). Expression analyses of sodium transporters at the same nephron segments further revealed a reduction in Na+-H+ exchanger isoform 3 (NHE3) in the renal cortex, while TAL-specific, furosemide-sensitive Na+-K+-2Cl- cotransporter (NKCC2) and NHE3 were significantly upregulated in the inner stripe of outer medulla. CsA-treated patients had a larger excretion of urinary NKCC2 protein at basal condition, and higher diuretic response to furosemide, showing increased FeNa+, FeCl- and FeCa2+ compared with both healthy controls and FK506-treated transplanted patients.

CONCLUSION

Altogether, these findings suggest that up-regulation of NKCC2 along the TAL facilitates sodium retention and contributes to the development of CsA-induced hypertension.

Different Clinicoradiological Characteristics of Posterior Reversible Encephalopathy Syndrome in Pediatric Oncology and Post-Bone Marrow Transplantation Cases: A Retrospective Study

Posterior reversible encephalopathy syndrome (PRES) is receiving increasing recognition in pediatrics. However, comparisons between PRES in pediatric oncology and post-bone marrow transplantation (BMT) are lacking. Therefore, we aimed to describe the risk factors and clinical and radiological features of PRES and investigate the differences between PRES in pediatric oncology and post-BMT. The PRES data of 13 patients from our center were combined with those of 217 cases from the PubMed, Scopus, and Web of Science databases. The patients were divided into either an oncology or a post-BMT group. We included 230 patients in the analysis, 26.1% of whom belonged to the post-BMT group. Oncology patients developed PRES at a younger age (p = 0.010) and were more likely to develop encephalopathy (p = 0.004). Systemic hypertension (S-HTN) preceding PRES occurred in 43.5% (66/154) of patients. Post-BMT patients were more likely to have S-HTN (p = 0.003). Cyclosporine levels were detected in 37 patients; 40.5% had supra-therapeutic levels. The radiological findings were atypical in 74.3% of patients, and delayed repeated imaging increased the occurrence of resolution (p = 0.004). Sixteen (7%) patients developed PRES recurrence after a median of 8 weeks, with the between-group difference being non-significant. Oncology patients were more likely to develop chronic epilepsy, while BMT patients were more likely to develop rare neurologic abnormalities (p < 0.001). In conclusion, atypical clinical presentation and imaging findings should not hinder the diagnosis of PRES. S-HTN is a risk factor, particularly in post-BMT patients. Supra-therapeutic levels of cyclosporine and previous exposure to immunosuppression did not increase the risk of recurrence.

Randomised controlled trial comparing rituximab to mycophenolate mofetil in children and young adults with steroid-dependent idiopathic nephrotic syndrome: study protocol

INTRODUCTION

Glucocorticoids induce remission in 90% of children with idiopathic nephrotic syndrome (INS). Some become steroid-dependent (SD) and require the addition of steroid sparing drugs such as calcineurin-inhibitors (CNI) or cyclophosphamide, to maintain remission. Considering the toxicity of these drugs, alternative interventions are needed for long-term treatment. The anti-CD20 antibody rituximab has shown promising steroid-sparing properties, with conflicting results in complicated forms of SD-INS. Mycophenolate mofetil (MMF) resulted effective in maintaining free-steroid remission, however, studies are limited to few uncontrolled trials with reported different dose of MMF.

METHODS AND ANALYSIS

This open-label, two-parallel-arm, superiority controlled randomised clinical trial will enrol children with SD-INS maintained in remission with oral glucocorticoids or CNI. Children and young adults will be randomised to either MMF (1.200 mg/m²) or rituximab (375 mg/m²) infusion. After enrolment, glucocorticoids will be tapered until complete withdrawal. We will enrol 160 children and young adults to detect as significant at the two-sided p value of 0.01 with a power >0.8 a reduction in the risk of 1-year relapse (primary end-point). As secondary endpoints, we will compare the amount of glucocorticoids required to maintain complete remission at 6 and 24 months.

ETHICS AND DISSEMINATION

The trial was approved by the local ethics boards (Comitato Etico Regione Liguria CER Liguria https://www.portalericerca-liguria.it/). We will publish the study results at international scientific meetings.

TRIAL REGISTRATION NUMBERS

NCT004585152.

Cyclosporine A-related neurotoxicity after haploidentical hematopoietic stem cell transplantation in children with hematopathy

Background

To evaluate cyclosporine A (CSA)-related neurotoxicity after haploidentical hematopoietic stem cell transplantation (HID-HSCT) in children with hematopathy.

Methods

This retrospective case series study included children with hematopathy who underwent HID-HSCT at Fujian Medical University Union Hospital between February 2013 and January 2017.

Results

Fifty-one children (39 males) were included in the study with a median age of 8 (range, 1.1–18) years. Seven patients (13.7%) developed CSA-related neurotoxicity after a median 38 (range, − 3 to 161) days from HID-HSCT. Hypertension (5/7, 71%) was the most common prodrome. Brain magnetic resonance imaging showed posterior reversible encephalopathy syndrome in six patients and atypical abnormalities in one patient. One patient died from grade IV graft-versus-host disease (GvHD) on day + 160, and six patients were alive at the last follow-up. Four patients (71.4%) achieved complete remission, while two patients developed secondary epilepsy and exhibited persistent MRI and electroencephalogram abnormalities at the 5-year follow-up. Hypertension after CSA was more common in patients with CSA-related neurotoxicity than in those without (71% vs. 11%, P = 0.002). Five-year overall survival did not differ significantly between patients with CSA-related neurotoxicity (85.7 ± 13.2%) and those without (65.8 ± 7.2%).

Conclusions

The incidence of CSA-related neurotoxicity in children with hematopathy undergoing HID-HSCT is relatively high.

Systemic treatment of psoriasis: from methotrexate to biologics

Psoriasis is one of the most frequent chronic inflammatory skin diseases and it has been of interest to many scientists for ages. The review presents data on all systemic treatment options, that are to date officially registered in Russian Federation for moderate-to-severe psoriasis. Aspects of the mechanism of action, efficacy and tolerability of both basic drugs (methotrexate, cyclosporine, acitretin) and biologics (infliximab, adalimumab, etanercept, certolizumab pegol, ustekinumab, guselkumab, secukinumab, ixekizumab, netakimab) and small molecules (tofacitinib, apremilast) are considered in detail. Special emphasis is placed on the important nuances of biological therapy: immunogenicity, drugs' survival and switch due to lack of efficacy. Invention of biologics signified a new era of moderate-to-severe psoriasis treatment. It became possible to achieve complete clinical remission more safely, which significantly improved the quality of life of patients. However, due to the unknown etiology of psoriasis, there is still no universal remedy that would allow to cure every patient, this fact makes scientists from all over the world keep conducting numerous clinical trials to find even more effective and safe therapeutic options.

Long-term Safety of Oral Systemic Therapies for Psoriasis: A Comprehensive Review of the Literature

Oral systemic therapies are important treatment options for patients with moderate-to-severe psoriasis, either as monotherapy or in therapy-recalcitrant cases as combination therapy with phototherapy, other oral systemics or biologics. Long-term treatment is needed to maintain sufficient disease control in psoriasis, but continuous use of systemic treatments is limited by adverse events (AEs) and cumulative toxicity risks. The primary aim of this comprehensive literature review was to examine the long-term safety profiles of oral agents commonly used in the treatment of adults with psoriasis. Searches were conducted in EMBASE and PubMed up to November 2018, and 157 relevant publications were included. Long-term treatment with acitretin could be associated with skeletal toxicity and hepatotoxicity, although evidence for skeletal toxicity is mixed and hepatotoxicity is rare, particularly at low doses. Other safety issues include hyperlipidaemia and potential for teratogenicity up to 2-3 years after discontinuation of treatment. There is a paucity of data on long-term treatment with apremilast. Continued exposure to apremilast does not seem to increase the incidence of common AEs, such as gastrointestinal (GI) AEs, upper respiratory tract infections and headache, while the long-term risks for depression, suicidal thoughts and weight loss are unknown. Long-term ciclosporin treatment is associated with renal toxicity, hypertension, non-melanoma skin cancer, neurological AEs and GI AEs. Long-term methotrexate treatment is associated with hepatotoxicity, GI AEs, haematological toxicity, renal toxicity and alopecia. Finally, long-term treatment with fumaric acid esters (FAE) is associated with GI AEs, flushing, lymphocytopenia, proteinuria and elevated liver enzymes. Median drug survival estimates varied considerably: ~  2.9-9.7 months for apremilast; ~ 5.4 months for ciclosporin; ~ 8.6 months for acitretin; ~ 12.1-21.6 months for methotrexate; and ~  54.8 months for FAE. These long-term safety profiles may help to guide clinicians to select the optimal oral systemic treatment for the long-term treatment of psoriasis in adults.

The Effect of Cyclosporine A on Dermal Fibroblast Cell - Transcriptomic Analysis of Inflammatory Response Pathway

BACKGROUND

The first immunosuppressive drug - cyclosporine A (CsA) has many unquestioned merits in maintaining organ transplants in patients, as well as, in the treatment of many inflammatory diseases, also associated with cutaneous manifestations. The main task of this drug is to suppress the inflammatory response at the sites of action, which is not well known.

OBJECTIVE

The objective of this study was to evaluate the influence of CsA in therapeutic concentration on the expression of genes associated with the inflammatory response pathway in normal human dermal fibroblasts (NHDF; CC-2511), and this study attempted to determine the mechanism of its action.

METHODS

The cytotoxicity MTT test was performed. The expression of the inflammatory response pathway genes was determined using HG-U133A_2.0 oligonucleotide microarrays. Statistical analysis was performed by GeneSpring 13.0 software using the PL-Grid platform.

RESULTS

Among the 5,300 mRNA, only 573 were changed significantly in response to CsA compared to the control fibroblasts (P≤0.05). CsA inhibited the expression of most genes associated with the inflammatory response in NHDFs. There were only 19 genes with a fold change (FC) lower than -2.0, among which EGR1, FOS, PBK, CDK1 and TOP2A had the lowest expression, as did CXCL2 which can directly impact inflammation. Furthermore, ZNF451 was strongly induced, and COL1A1, COL3A1, IL33, TNFRSFs were weakly up-regulated (FC lower than 2.0).

CONCLUSION

The CsA in therapeutic concentration influences the genes linked to the inflammatory response (in the transcriptional level) in human dermal fibroblasts. The findings suggest that the potential mechanism of CsA action in this concentration and on these genes can be associated with a profibrotic and proapoptotic, and genotoxic effects.

Enhanced survival of human-induced pluripotent stem cell transplant in parkinsonian rat brain by locally applied cyclosporine

A major limitation with cell transplantation in patients is the unimpressive number of cells survived. The death of grafted cells involves apoptosis and immunorejection. In this review, we encapsulate the recent preclinical development that improves the survival of grafted cells and mitigates the immunorejection of human-induced pluripotent stem cells (iPSCs) through co-grating nanoparticles-containing cyclosporine A (NanoCsA) in hemiparkinsonian rats. The study supported the notion that NanoCsA allows for long-lasting CsA discharge and limits immunorejection of human iPSC xenograft in a 6-hydroxydopamine Parkinson's disease rat model.

NanoCsA improves the survival of human iPSC transplant in hemiparkinsonian rats

Increasing evidence has supported that transplantation of human stem cells induces neuroprotective and reparative effects in animal models of Parkinson's disease (PD). However, without systemic immunosuppressive therapy, most of these grafted cells are rejected by the hosts. Long term and systemic injection of cyclosporine-A (CsA) is required to maintain the survival of grafted cells. The purpose this study is to examine a new treatment strategy to suppress the immunorejection by locally co-grafting of polylactic/glycolic acid nanoparticles containing CsA (NanoCsA) with differentiated human induced pluripotent stem cells (iPSCs). In the in vitro media, NanoCsA provided sustained release of CsA for >6 weeks. The differentiated human iPSCs were co-grafted with NanoCsA or NanoVeh (nanoparticle without CsA) to the striatum of unilaterally 6-hydroxydopamine -lesioned rats. NanoCsA/iPSCs co-graft significantly improved locomotor activity compared to NanoVeh/iPSCs co-grafts or iPSC grafts + sytemic CsA at 1 month after transplantation. Brain tissues were collected for measurements of tyrosine hydroxylase (TH) and human marker Stem121 immunoreactivity. Cografting with NanoCsA/iPSCs, compared to NanoVeh/iPSCs, significantly increased TH and Stem121 immunoreactivity as well as tumor formation in the lesioned striatum. Taken together, our study supports that NanoCsA provides long-lasting CsA release and reduces immunorejection of human iPSCs xenograft in a 6-hydroxydopamine rat model of PD.

Renal Oxidative Stress and Inflammatory Response in Perinatal Cyclosporine-A Exposed Rat Progeny and its Relation to Gender

Background and Aim of the Work:

The current study postulated that cyclosporine A (CSA) could induce gender-specific renal damage. Hence, the current study aims to investigate the nephrotoxic effect of perinatal exposure of male and female rat progeny to CSA. Moreover, it aims to evaluate the oxidative stress and inflammation as a possible pathophysiologic mechanism.

Materials and Methods:

Female rats were randomly allocated to two groups of four and assigned to undergo either CSA (15 mg/kg/day; the 6^th day after conception and continuing until the progeny were weaned) or vehicle treatment as control groups. At the age of 6 weeks, the progeny were divided into the following four groups: male progeny of control-group mothers (M-vehicle, 7); male progeny of CSA-treated mothers (M-CSA, 9); female progeny of control-group mothers (F-vehicle, 7); and female progeny of CSA-treated mothers (F-CSA, 6). Serum adiponectin, tumor necrosis factor-α (TNF-α) and creatinine, creatinine clearance, and urinary 8-isoprostane were measured. Histopathological examination by hematoxylin and eosin stain of Kidney was carried out.

Results:

Proteinuria and decreased creatinine clearance are significant in M-CSA than M-vehicle and F-CSA. 8-isoprostane is lower in F-CSA than F-vehicle. Increased TNF-α and decreased adiponectin levels in M-CSA than M-vehicle were observed. No significant differences were found in female rat groups.

Conclusion:

From the current study, it could be concluded that CSA could induce renal inflammation as well as oxidative stress that may explain the impaired renal function. The sex difference was a prominent finding in their vulnerability to CSA effects.

T cell inhibition by pogostone from Pogostemon cablin (Blanco) Benth: In vitro and in vivo immunosuppressive analysis

Various plant-derived compounds exhibit immunosuppressive activity in pre-clinical investigations, suggesting that they may serve as natural alternatives for the prevention of inflammatory disorders and autoimmune diseases. The aim of the current study was to explore the immunosuppressive potential of pogostone (PO) derived from Pogostemon cablin (Blanco) Benth. Carboxyfluorescein diacetate succinimidyl ester-labeled cell tracking demonstrated that PO (20–80 µM) inhibited Concanavalin A (ConA)-stimulated lymphocyte proliferation, which was mediated by G₀/G₁ phase arrest and accompanied by significant decreases in the expression of CD69 (early-stage activation marker) and CD25 (mid-stage activation marker) in T cells, as indicated by flow cytometry analysis. Furthermore, the proliferation blocking ability of PO (5–80 µM) was not associated with cytotoxicity in normal lymphocytes or apoptosis in ConA-stimulated lymphocytes. The inflammatory cytokine profile determination using a cytometric beads assay revealed that PO inhibited release of anti-inflammatory interleukin (IL)-10 and pro-inflammatory IL-6 from the stimulated lymphocytes. Furthermore, PO (10, 20 or 40 mg/kg) ameliorated the T-cell mediated delayed type hypersensitivity response in Balb/c mice by reducing leukocyte infiltration and tissue edema, providing a further validation of the direct immunosuppressive activity of PO. Together, the present data suggest that PO would suppress T cell response via a direct non-cytotoxic inactivation at the early stage, accompanied by regulation of the inflammatory cytokine profile, which highlights clinical implications for treatment of immune-based disorders.

Immune-Modulating Therapy for Rheumatologic Disease: Implications for Patients with Diabetes

Immune modulators used to treat rheumatologic disease have diverse endocrine effects in patients with diabetes. Providers should be aware of these effects given that diabetes and rheumatologic disease overlap in prevalence and cardiovascular morbidity. In patients with type 1 diabetes, clinical trials have demonstrated that immune modulators used early in the disease can improve pancreatic function, though their efficacy in adults with longstanding autoimmune diabetes is unknown. In patients with type 2 diabetes, hydroxychloroquine is an effective antihyperglycemic and may be preferred for rheumatologic use in patients with difficult glycemic control. In patients without diabetes, hydroxychloroquine and tumor necrosis factor (TNF) inhibitors have been found to decrease diabetes incidence in observational studies. Additionally, dapsone and sulfasalazine alter erythrocyte survival resulting in inaccurate HbA1c values. These multifaceted effects of immune modulators create a need for coordinated care between providers treating patients with diabetes to individualize medication selection and prevent hypoglycemic events. More research is needed to determine the long-term outcomes of immune modulators in patients with diabetes.

Mechanisms of cyclosporine-induced renal cell apoptosis: a systematic review

BACKGROUND/AIMS

Chronic cyclosporine A (CsA) nephrotoxicity (CCN) is an important cause of chronic renal dysfunction with no effective clinical intervention. To further elucidate the mechanisms of renal cell apoptosis in CCN, all relevant in vivo studies on this subject were analyzed.

METHODS

We searched for in vivo studies on the mechanisms of CsA-induced renal cell apoptosis in Medline (1966-July 2010), Embase (1980-July 2010) and ISI (1986-July 2010). The studies were evaluated for their quality according to a set of in vivo standards, data extracted according to PICOS, and then synthesized.

RESULTS

Renal cell apoptosis was an important feature of CCN and an important factor of renal dysfunction. First, CsA could upregulate Fas/Fas ligand, downregulate Bcl-2/Bcl-XL, and increase caspase-1 and caspase-3. Second, it could induce oxidative stress and damage the antioxidant defense system. Third, it could increase endoplasmic reticulum stress protein in a dose- and time-dependent manner. Fourth, CsA could impair the urine concentration and decrease the expression of hypertonicity-induced genes. Fifth, CsA-induced renal cell apoptosis was significantly decreased by blocking the angiotensin II type 1 receptor using losartan.

CONCLUSIONS

The in vivo mechanisms for CCN are more complex than those found in vitro. CsA can induce renal cell apoptosis using five pathways in vivo and activated caspases might be the ultimate intersection of these pathways and the common intracellular pathway mediating apoptosis. These data provide new potential points for intervention and need to be confirmed by further studies.

The protective effects of omega 3 fatty acids and sesame oil against cyclosporine A-induced nephrotoxicity

Cyclosporine A (CsA) is a drug used in autoimmune disorders and organ transplantations. Omega 3 fatty acids (O-3) and sesame oil (SO) have antioxidant properties. We aimed to investigate and compare the protective effects of O-3 and SO against CsA-induced nephrotoxicity. Seven groups of male Wistar albino rats were included in the study. In group 1 (control), saline was administered, and in group 2, CsA (subcutaneously) was administered. In group 3, CsA+SO (orally; p.o.) was given; in group 4, CsA+O-3 (p.o.) was given; and in group 5, CsA+SO+O-3 was given. In group 6, SO was administered, and in group 7, O-3 was administered. After 15 days of treatment, kidneys were excised. Histopathological evaluation, apoptotic cell count, and renal/hepatic function tests were performed. In group 2, vacuolar degeneration and necrosis of tubular cells as well as hemorrhagic foci were observed; the apoptotic cell number was higher than in the control (P < 0.001). In groups 3, 4, and 5, tubular scores and apoptotic cell count were lower than in group 2 (P < 0.01 and P < 0.001, respectively). In groups 6 and 7, healthy renal histology and a few apoptotic cells were determined. In groups 2, 3, 4, and 5, blood urea nitrogen was higher and albumin was lower than in the control (P < 0.001). Liver enzymes were unchanged. O-3/SO showed similar protective effects against CsA-induced nephrotoxicity, as revealed by a remarkable decrease in histopathological changes and apoptotic cell count. However, impaired renal function tests were not improved with O-3/SO treatment. SO and O-3 can be used as chemoprotectants against CsA.

An evaluation of sirolimus in renal transplantation

INTRODUCTION

Sirolimus is a powerful antiproliferative immunosuppressive drug approved for the prevention of kidney allograft rejection. By its unique mechanism of action, sirolimus provides a multitude of clinical potential and has been used effectively in different drug combinations. Extensive experience has been gained regarding the best timing of its application, side effect profile and potential benefits and limitations compared with other immunosuppressive drugs.

AREAS COVERED

The authors evaluate the recent experience with sirolimus in kidney transplantation. Pivotal randomized controlled trials were used to provide an overview with special attention to pharmacokinetic and dynamic aspects of sirolimus, its current clinical use as well as perspectives for its future role.

EXPERT OPINION

Sirolimus enriches the possibilities of immunosuppressive therapies after renal transplantation. Beneficial effects toward kidney function by allowing CNI sparing, lower incidence of malignancies and less viral infections have been suggested. Sirolimus should be used cautiously in de novo patients for reasons of wound healing. An early conversion to a sirolimus-based CNI-free regimen has shown promising results, whereas late conversion is more challenging. Finally, sirolimus-associated side effects are causing tolerability concerns and frequent discontinuations. Future research should aim to better define the therapeutic window and those patients most likely to benefit.

New-onset psoriasis in a maintenance hemodialysis patient

New-onset psoriasis is extremely rare in hemodialysis (HD) patients, and several trials of dialysis therapies (HD and peritoneal dialysis) in psoriasis have indicated remarkable improvement in skin lesions and well-being even in patients without renal impairment. We describe a patient who developed severe psoriasis despite undergoing chronic maintenance hemodialysis for 5 years and was treated successfully with oral cyclosporin A.

Posterior reversible encephalopathy syndrome in children with kidney diseases

Posterior reversible encephalopathy syndrome (PRES) was originally used to describe a reversible, predominantly posterior leukoencephalopathy in patients who had renal insufficiency, hypertension, or who received immunosuppressive therapy. Since PRES is prevalent in children with kidney diseases, awareness and understanding of it is important for practicing pediatric nephrologists. A comprehensive approach to the diagnosis of PRES includes thorough determination of predisposing factors, clinical symptoms, and mandatory appropriate imaging. Unfortunately, the pathophysiology of PRES is still obscure and specificity of radiological examination has not yet been established. Two major predisposing factors, namely hypertension and calcineurin inhibitors, are well recognized. In addition, nephrotic syndrome is a common underlying condition for development of PRES. Frequent symptoms include altered consciousness (coma, stupor, lethargy, confusion), seizure, headache, and visual disturbance. Most of these symptoms usually develop abruptly and resolve within a few weeks after proper management. Cranial magnetic resonance (MR) imaging is the first-line modality of imaging studies for detecting PRES. Diffusion-weighted imaging with quantification of apparent diffusion coefficient (ADC) values by ADC mapping may provide more accurate and specific images in the future.

Clinical course and outcome of children with steroid-sensitive nephrotic syndrome

We conducted a retrospective study on children with primary nephrotic syndrome (NS) to evaluate the clinical course and outcome of children with steroid-sensitive NS (SSNS). The medical records of 226 children, median 3.46 years (min 1.00, max 15.08) who referred to our clinics with SSNS between January 1978 and September 2005 were reviewed and entered into the study. Minimum duration of follow-up was 5 years and maximum 20 years (median 7.25 years). Of 226 patients who were treated with corticosteroids, 38 (16.8%) had no relapse but the remaining 188 (83.2%) patients experienced several relapses of which 128 patients (56.6%) required additional immunosuppressive agents for the remission. Of these, 122 (95%) were treated with levamisole, 22 (17%) with cyclosporine, 36 (28%) with cyclophosphamide, and ten (7.8 %) treated with mycophenolate mofetil. Several patients had to switch from one medication to others due to lack of response. On the last follow-up visit, 64(28.3%) patients were still under treatment, some patients had taken all of the above-mentioned drugs but still had multiple recurrences. Only 103 (45.5%) patients were in remission off the drug more than 3 years. This study shows that nearly one-third of pediatric patients with SSNS experience frequent relapses despite the combination of multiple immunosuppressive medications, which may continue until adulthood.

Mitochondria-targeted peptide accelerates ATP recovery and reduces ischemic kidney injury

The burst of reactive oxygen species (ROS) during reperfusion of ischemic tissues can trigger the opening of the mitochondrial permeability transition (MPT) pore, resulting in mitochondrial depolarization, decreased ATP synthesis, and increased ROS production. Rapid recovery of ATP upon reperfusion is essential for survival of tubular cells, and inhibition of oxidative damage can limit inflammation. SS-31 is a mitochondria-targeted tetrapeptide that can scavenge mitochondrial ROS and inhibit MPT, suggesting that it may protect against ischemic renal injury. Here, in a rat model of ischemia-reperfusion (IR) injury, treatment with SS-31 protected mitochondrial structure and respiration during early reperfusion, accelerated recovery of ATP, reduced apoptosis and necrosis of tubular cells, and abrogated tubular dysfunction. In addition, SS-31 reduced medullary vascular congestion, decreased IR-mediated oxidative stress and the inflammatory response, and accelerated the proliferation of surviving tubular cells as early as 1 day after reperfusion. In summary, these results support MPT as an upstream target for pharmacologic intervention in IR injury and support early protection of mitochondrial function as a therapeutic maneuver to prevent tubular apoptosis and necrosis, reduce oxidative stress, and reduce inflammation. SS-31 holds promise for the prevention and treatment of acute kidney injury.

A Review of Laboratory and Clinical Data Supporting the Safety and Efficacy of Cyclosporin A in Traumatic Brain Injury

For decades, cyclosporin A (CsA) has proved to be safe and effective for use in transplantation. In the past 10 years, this agent has shown neuroprotective effects in animal models of traumatic brain injury (TBI). This review article provides a critical overview of the literature on CsA neuroprotective effects in animal studies and current findings of clinical trials in the treatment of TBI with an emphasis on the possible CsA molecular mechanism of action. Animal data provide compelling evidence of the therapeutic benefits of CsA in TBI, but the outcome indices are heterogeneous with respect to the animal model of TBI as well as the route, dose, and timing of CsA administration. Similarly, clinical studies (phase II trials) adapting almost identical patient inclusion criteria have demonstrated the safety of CsA use in TBI, but the clinical trials are also heterogeneous based on study design, especially with regard to the variable timing of CsA administration after TBI. In view of the translational shortcomings of the preclinical studies and the rather pilot nature of the limited clinical trials that recently reached phase III, we offer guidance on the future directions of laboratory investigations on CsA that could improve the safety and efficacy of this agent in subsequent larger clinical trials.

Mechanisms of renal cell apoptosis induced by cyclosporine A: a systematic review of in vitro studies

BACKGROUND

Chronic cyclosporine A (CsA) nephrotoxicity (CCN) is a major cause of chronic renal dysfunction and has no effective clinical interventions yet.

OBJECTIVE

To reveal the mechanisms of renal cell apoptosis in CCN, we analyzed all in vitro studies of such mechanisms.

METHODS

We collected all in vitro studies about the mechanisms of renal cell apoptosis induced by CsA in Medline (1966 to July 2010), Embase (1980 to July 2010) and ISI (1986 to July 2010), evaluated their quality according to in vitro standards and extracted data following the PICOS principles and synthesized the data.

RESULTS

First,CsA could upregulate Fas and Fas-L expression, increase FADD and apoptosis enzymes (caspase-2, -3, -4, -7, -8, -9 and -10) and downregulate the Bcl-2 and Bcl-xL. Second, CsA could induce oxidative stress and damage the antioxidant defense system. Third, CsA could increase the expression of HERP, GRP78 and CHOP. Fourth, CsA could induce renal cell apoptosis and increase their iNOS and p53 expression in cultured cells.

CONCLUSIONS

At least four pathways are involved in renal cell apoptosis induced by CsA in different cell species. Caspases might be their final common pathway in vitro. They might all provide potential points for interventions, but these need to be confirmed in vivo.

Evaluation of the novel protein kinase C inhibitor sotrastaurin as immunosuppressive therapy after renal transplantation

IMPORTANCE OF THE FIELD

The prevalence of acute renal allograft rejection has decreased substantially in past decades due to new and more specific immunosuppressive compounds but improvements in long-term graft function have not been achieved. There is a large need for new immunosuppressive agents that lack toxicity of current agents such as calcineurin inhibitors but show high synergistic efficiency in preventing rejection processes.

AREAS COVERED IN THIS REVIEW

This review summarizes data concerning the pharmacokinetics, pharmacodynamics and clinical efficacy of the new PKC inhibitor sotrastaurin with a focus on renal transplantation. The article contains information that has been presented at international transplant meetings and congresses and that has been published between 2006 and 2010. Additionally, current ongoing trials are described in detail.

WHAT THE READER WILL GAIN

Immunosuppressive regimens after kidney transplantation consist of a combination of several agents in order to minimize drug toxicity. Therefore, the reader is presented with the most up-to-date/current developments in sotrastaurin applications in Phase I and II trials with emphasis on data maintained from studies that combined sotrastaurin with established agents such as mycophenolic acid and tacrolimus.

TAKE HOME MESSAGE

Several trials are ongoing and planned to determine the optimal immunosuppressive regimen to benefit from sotrastaurin's distinct mechanism of action.

Whole blood flow cytometric measurement of NFATc1 and IL-2 expression to analyze cyclosporine A-mediated effects in T cells

The calcineurin inhibitor Cyclosporine A (CsA) is one of the crucial immunosuppressive drugs given after organ transplantation. The small therapeutic window of CsA generates the dilemma that efficient and toxic drug doses differ only slightly. Moreover, these threshold concentrations differ considerably between individuals; therefore, functional assays are urgently needed. We explored whether the transcription factor NFATc1, a direct as well as indirect target of CsA, can be used as a potential biomarker to determine the individual immunosuppressive activity of CsA. First, in isolated human T cells we showed that flow cytometry is practicable to measure NFATc1, the most abundant NFATc isoform in activated T cells. Second, for whole blood we developed a flow cytometric assay to determine in parallel the inducible transcription factor NFATc1 and the cytokine IL-2 in stimulated T cells. We found that added CsA inhibits both the expression of NFATc1 and IL-2 in T cells of stimulated whole blood samples with IC(50) values of 200 and 150 nM, respectively. The intra- and inter-assay variability was low, and clinical practicability was good. Further experiments have to demonstrate whether the parallel cytometric measurement of NFATc1 and IL-2 in whole blood is a good predictor of individual CsA efficacy and toxicity in CsA-treated patients.

Treatment of Duchenne muscular dystrophy with ciclosporin A: a randomised, double-blind, placebo-controlled multicentre trial

BACKGROUND

Duchenne muscular dystrophy is a rare X-linked progressive disease characterised by loss of ambulation at about age 10 years, with death in early adulthood due to respiratory and cardiac insufficiency. Steroids are effective at slowing the progression of muscle weakness; however, their use is limited by side-effects, prompting the search for alternatives. We assessed the effect of ciclosporin A as monotherapy and in combination with intermittent prednisone for the treatment of ambulant patients with this disorder.

METHODS

Our study was a parallel-group, placebo-controlled, double-blind, multicentre trial at trial sites of the German muscular dystrophy network, MD-NET, over 36 months. Ambulant patients with Duchenne muscular dystrophy who were aged 5 years or older were randomly assigned to receive either ciclosporin A (3·5-4·0 mg/kg per day) or matching placebo. Allocation was done centrally with computer-generated random numbers. Patients and investigators were masked to the allocated treatment. After 3 months of treatment, both groups were also given intermittent prednisone for a further 12 months (0·75 mg/kg, alternating 10 days on with 10 days off). All patients who received at least one dose of study drug or placebo were included in the primary analysis. The primary outcome measure was manual muscle strength measured on the Medical Research Council (MRC) scale. This trial is registered with the German clinical trial register DRKS, number DRKS00000445.

FINDINGS

77 patients were randomly assigned to the ciclosporin A group and 76 to the placebo group; 73 patients on ciclosporin A and 73 on placebo received at least one dose and were available for efficacy analyses. 3 months of treatment with ciclosporin A alone did not show any significant improvement in primary outcome measures (mean change in the proportion of a possible total MRC score [%MRC] was -2·6 [SD 6·0] for patients on ciclosporin A and -0·8 [4·9] for patients on placebo; adjusted group difference estimate -0·88, 97·5% CI -2·6 to 0·9; p=0·26). The combination of ciclosporin A with intermittent steroids was not better than intermittent steroids alone over 12 months (mean change in %MRC was 0·7 [7·1] for patients on ciclosporin A and -0·3 [7·9] for patients on placebo; adjusted group difference estimate -0·85, -3·6 to 1·9; p=0·48). Numbers of adverse events (75 in patients on ciclosporin A and 74 on placebo) and serious adverse events (four with ciclosporin A and four with placebo) did not differ significantly between groups.

INTERPRETATION

Ciclosporin A alone or in combination with intermittent prednisone does not improve muscle strength or functional abilities in ambulant boys with Duchenne muscular dystrophy, but is safe and well tolerated.

FUNDING

German Federal Ministry of Education and Research, Action Benni and co eV, Novartis Pharma AG, and Deutsche Gesellschaft für Muskelkranke eV.

Mitochondrial involvement in cardiac apoptosis during ischemia and reperfusion: can we close the box?

Myocardial ischemia is the main cause of death in the Western societies. Therapeutic strategies aimed to protect the ischemic myocardium have been extensively studied. Reperfusion is the definitive treatment for acute coronary syndromes, especially acute myocardial infarction; however, reperfusion has the potential to exacerbate tissue injury, a process termed reperfusion injury. Ischemia/reperfusion (I/R) injury may lead to cardiac arrhythmias and contractile dysfunction that involve apoptosis and necrosis in the heart. The present review describes the mitochondrial role on cardiomyocyte death and some potential pharmacological strategies aimed at preventing the opening of the box, i.e., mitochondrial dysfunction and membrane permeabilization that result into cell death. Data in the literature suggest that mitochondrial disruption during I/R can be avoided, although uncertainties still exist, including the fact that the optimal windows of treatment are still fairly unknown. Despite this, the protection of cardiac mitochondrial function should be critical for the patient survival, and new strategies to avoid mitochondrial alterations should be designed to avoid cardiomyocyte loss.

In vitro modulation of ABCB1/P-glycoprotein expression by polyphenols from Mangifera indica

Many plant compounds are able to modulate the activity and/or the expression of the major multidrug transporter ABCB1/P-glycoprotein (P-gp). In this study, mango (Mangifera indica L.) stem bark extract (MSBE), its main polyphenol mangiferin and the mangiferin aglycone derivative norathyriol, as well as catechin, gallic acid and quercetin, were investigated for their potential ability to influence ABCB1 gene and P-gp expression in HK-2 cells, a proximal tubule line constitutively expressing this transporter. Western blot analysis demonstrated a concentration-dependent decrease in P-gp in cells cultured in the presence of MSBE for 72 h. Gallic acid and quercetin also decreased the levels of P-gp at all studied concentrations, whereas catechin was almost ineffective. However, in cells exposed to mangiferin (10-200 microM), the P-gp amount showed a concentration- and time-dependent increase, being 2-fold higher than the controls after 72 h. Norathyriol (5 microM) induced P-gp, but the effect decreased at higher concentrations. The changes in the P-gp protein amount were correlated with relative changes in the ABCB1 mRNA content and with the efflux activity of the transporter. The transcriptional inhibitor 1-d-ribofuranosylbenzimidazole (DRB) contrasted the increased expression of ABCB1 by mangiferin, suggesting that the increase could be due to transcriptional up-regulation of ABCB1 mRNA. Mangiferin-treated cells overexpressing the transporter were protected against the cytotoxicity of the known P-gp substrate cyclosporine A. However, the opposite effect was not observed in cells pretreated with MSBE. These results demonstrate that MSBE and mango polyphenols, already shown in our previous studies to influence P-gp activity, may also interact with ABCB1/P-gp at the expression level. In particular, we show for the first time that the main mango polyphenol mangiferin up-regulates this multidrug transporter. The molecular mechanisms and the consequences of these effects, including the possibility of interactions with conventional drugs or other herbal constituents, remain to be elucidated.

[Ciclosporin-associated cerebral tumor-like location of Behçet's disease]

INTRODUCTION

Cerebral tumor-like location is uncommon in the course of Behçet's disease. We report herein a patient with tumor-like lesions associated with ciclosporin therapy.

CASE REPORT

A 45-year-old male treated for 17 years with colchicine and ciclosporin for Behçet's disease with cutaneomucosal, ocular and joint involvement was admitted for sudden onset of meningo-encephalitis with lymphocytic meningitis. CT-scan showed a nodular lesion of the brainstem enhanced by iodine. Ciclosporin was discontinued; prednisone and IV cyclophosphamide were started. After three months of favorable outcome, a relapse occurred when ciclosporin was started again. MRI showed two additional capsulothalamic lesions. Prednisone and cyclophosphamide were started again with a favorable response and minimal sequelae.

CONCLUSION

The main challenge in cerebral tumor-like location of Behçet's disease is to rule out other inflammatory or tumor processes. Neuronal toxicity of ciclosporin limits indications for this therapy in Behçet's disease.

Neutral sphingomyelinase 2 (nSMase2) is a phosphoprotein regulated by calcineurin (PP2B)

We previously reported that exposure of human airway epithelial cells to oxidative stress increased ceramide generation via specific activation of neutral sphingomyelinase2 (nSMase2). Here we show that nSMase2 is a phosphoprotein exclusively phosphorylated at serine residues. The level of nSMase2 phosphorylation can be modulated by treatment with anisomycin or phorbol 12-myristate 13-acetate (PMA/12-O-tetradecanoylphorbol-13-acetate), suggesting that p38 mitogen-activated protein kinase (MAPK) and protein kinases Cs are upstream of nSMase2 phosphorylation. Oxidative stress enhances both the activity and phosphorylation of nSMase2. Strikingly, we show here that nSMase2 is bound directly by the phosphatase calcineurin (CaN), which acts as an on/off switch for nSMase2 phosphorylation in the presence or absence of oxidative stress. Specifically, CaN is being inhibited/degraded and therefore does not bind nSMase2 under oxidative stress, and a mutant nSMase2 that lacks the CaN binding site exhibits constitutively elevated phosphorylation and increased activity relative to wild type nSMase2. Importantly, the phosphorylation and activity of the mutant no longer responds to oxidative stress, confirming that CaN is the critical link that allows oxidative stress to modulate nSMase2 phosphorylation and function.