311 resultados para cyclosporine A
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PURPOSE: Hyperhomocyst(e)inaemia is an important risk factor for atherosclerosis, which is currently a major cause of death in renal transplant patients. The aim of this study was to assess the influence of immunosuppressive therapy on homocyst(e)inemia in renal transplant recipients. METHODS: Total serum homocysteine (by high performance liquid chromatography), creatinine, lipid profile, folic acid (by radioimmunoassay-RIA) and vitamin B12 (by RIA) concentrations were measured in 3 groups. Group I patients (n=20) were under treatment with cyclosporine, azathioprine, and prednisone; group II (n=9) were under treatment with azathioprine and prednisone; and group III (n=7) were composed of renal graft donors for groups I and II. Creatinine, estimated creatinine clearance, cyclosporine trough level, lipid profile, folic acid, and vitamin B12 concentrations and clinical characteristics of patients were assessed with the aim of ascertaining determinants of hyperhomocyst(e)inemia. RESULTS: Patient ages were 48.8 ± 15.1 yr (group I), 43.3 ± 11.3 yr (group II); and 46.5 ± 14.8 yr (group III). Mean serum homocyst(e)ine (tHcy) concentrations were 18.07 ± 8.29 mmol/l in renal transplant recipients; 16.55 ± 5.6 mmol/l and 21.44 ± 12.1 mmol/l respectively for group I (with cyclosporine) and group II (without cyclosporine) (NS). In renal donors, tHcy was significantly lower (9.07 ± 3.06 mmol/l; group I + group II vs. group III, p<0.008). There was an unadjusted correlation (p<0.10) between age (r=0.427; p<0.005) body weight (r=0.412; p<0.05), serum creatinine (r=0.427; p<0.05), estimated creatinine clearance (r=0.316; p<0.10), and tHcy in renal recipients (group I +II). Independent regressors (r²=0.46) identified in the multiple regression model were age (coefficient= 0.253; p=0.009) and serum creatinine (coefficient=8.07; p=0.045). We found no cases of hyperhomocyst(e)inemia in the control group. In contrast, 38% of renal recipients had hyperhomocyst(e)inemia: 7 cases (35%) on cyclosporine and 4 (45%) without cyclosporine, based on serum normal levels. CONCLUSIONS: Renal transplant recipients frequently have hyperhomocyst(e)inemia. Hyperhomocyst(e)inemia in renal transplant patients is independent of the scheme of immunosuppression they are taking. The older the patients are and the higher are their serum creatinine levels, the more susceptible they are to hyperhomocyst(e)inemia following renal transplantation.
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RESUMO:Contexto: A avaliação do estado de nutrição do doente com indicação para transplante hepático (TH) deve ser abrangente, considerando o amplo espetro de situações clínicas e metabólicas. As alterações metabólicas relacionadas com a doença hepática podem limitar a aplicação de métodos de avaliação nutricional, subestimando a desnutrição. Após o TH, é expectável a reversão dos distúrbios metabólicos da doença hepática, pela melhoria da função do fígado. No entanto, algumas complicações metabólicas podem surgir após o TH, relacionadas com a má-nutrição, a desnervação hepática e o uso prolongado de imunossupressão, comprometendo os resultados clínicos a longo-prazo. A medição longitudinal e confiável do metabolismo energético e dos compartimentos corporais após o TH, avaliada em conjunto com fatores influentes no estado de nutrição, pode identificar precocemente situações de risco e otimizar e individualizar estratégias clínicas e nutricionais com vantagens no prognóstico. Objetivo: Avaliar longitudinalmente, a curto prazo, o estado de nutrição após o TH em doentes com insuficiência hepática por doença crónica e identificar os fatores, para além da cirurgia, que determinam diferentes evoluções do metabolismo energético e da composição corporal. Métodos: Foi estudada uma coorte de indivíduos com indicação para TH por doença hepática crónica, admitidos consecutivamente para TH ortotópico eletivo, durante 2 anos. Foram programados 3 momentos de avaliação: na última consulta pré-TH (T0), logo que adquirida autonomia respiratória e funcional após o TH (T1) e um mês após o TH (T2). Nesses momentos, foram medidos no mesmo dia: o suprimento nutricional por recordatório das últimas 24 horas, o estado de nutrição por Avaliação Subjetiva Global (ASG), o gasto energético em repouso (GER) por calorimetria indireta, a antropometria, a composição corporal por bioimpedância elétrica tetrapolar multifrequências e a força muscular por dinamometria de preensão palmar. O índice de massa magra (IMM) e a massa celular corporal (MCC) foram usados como indicadores do músculo esquelético e a percentagem de massa gorda (%MG) e o índice de massa gorda (IMG) como indicadores de adiposidade. O GER foi comparado com o estimado pelas fórmulas de Harris-Benedict para classificação do estado metabólico em:hipermetabolismo (GER medido >120% do GER estimado), normometabolismo (GER medido entre 80 e 120% do GER estimado) e hipometabolismo (GER medido <80% do GER estimado). Foi utilizada análise multivariável: por regressão logística, para identificar variáveis associadas à possibilidade (odds ratio – OR) de pertencer a cada grupo metabólico pré-TH; por regressão linear múltipla, para identificar variáveis associadas à variação dos compartimentos corporais no período pós-TH; e por modelos de efeitos mistos generalizados, para identificar variáveis associadas à evolução do GER e dos compartimentos corporais entre o período pré- e pós-TH. Resultados: Foram incluídos 56 indivíduos com idade, média (DP), 53,7 (8,5) anos, 87,5% do sexo masculino, 23,2% com doença hepática crónica de etiologia etanólica. Após o TH, em 60,7% indivíduos foi administrado regime imunossupressor baseado no tacrolimus. Os indivíduos foram avaliados [mediana (AIQ)] 90,5 (P25: 44,2; P75: 134,5) dias antes do TH (T0), 9,0 (P25: 7,0; P75: 12,0) dias após o TH (T1) e 36,0 (P25: 31,0; P75: 43,0) dias após o TH (T2). Após o TH houve melhoria significativa do estado de nutrição, com diminuição da prevalência de desnutrição classificada pela ASG (37,5% em T0, 16,1% em T2, p<0,001). Antes do TH, 41,1% dos indivíduos eram normometabólicos, 37,5% hipometabólicos e 21,4% hipermetabólicos. A possibilidade de pertencer a cada grupo metabólico pré-TH associou-se à: idade (OR=0,899, p=0,010) e desnutrição pela ASG (OR=5,038, p=0,015) para o grupo normometabólico; e índice de massa magra (IMM, OR=1,264, p=0,049) e etiologia viral da doença hepática (OR=8,297, p=0,019) para o grupo hipermetabólico. Não se obteve modelo múltiplo para o grupo de hipometabólico pré-TH, mas foram identificadas associações univariáveis com a história de toxicodependência (OR=0,282, p=0,047) e com a sarcopénia pré- TH (OR=8,000, p=0,040). Após o TH, houve normalização significativa e progressiva do estado metabólico, indicada pelo aumento da prevalência de normometabolismo (41,1% em T0, 57,1% em T2, p=0,040). Foram identificados diferentes perfis de evolução do GER após o TH, estratificado pelo estado metabólico pré-TH: no grupo hipometabólico pré-TH, o GER (Kcal) aumentou significativa e progressivamente (1030,6 em T0; 1436,1 em T1, p=0,001; 1659,2 em T2, p<0,001); no grupo hipermetabólico pré-TH o GER diminuiu significativa e progressivamente (2097,1 em T0; 1662,5 em T1, p=0,024; 1493,0 em T2, p<0.001); no grupo normometabólico não houve variações significativas. Os perfis de evolução do GER associaram-se com: peso corporal (β=9,6, p<0,001) e suprimento energético (β=13,6, p=0,005) na amostra total; com peso corporal (β=7,1, p=0,018) e contributo energético dos lípidos (β=18,9, p=0,003) no grupo hipometabólico pré-TH; e com peso corporal (β=14,1, p<0,001) e desnutrição pela ASG (β=-171,0, p=0,007) no grupo normometabólico pré-TH.Houve redução transitória dos compartimentos corporais entre T0 e T1, mas a maioria destes recuperou para valores semelhantes aos pré-TH. As exceções foram a água extracelular, que diminuiu entre T0 e T2 (média 18,2 L e 17,8 L, p=0,042), a massa gorda (média 25,1 Kg e 21,7 Kg, p<0,001) e o IMG (média 10,6 Kg.m-2 e 9,3 Kg.m-2, p<0,001) que diminuíram entre T1 e T2. Relativamente à evolução dos indicadores de músculo esquelético e adiposidade ao longo do estudo: a evolução do IMM associou-se com força de preensão palmar (β=0,06, p<0,001), creatininémia (β=2,28, p<0,001) e número total de fármacos administrados (β=-0,21, p<0,001); a evolução da MCC associou-se com força de preensão palmar (β=0,16, p<0,001), creatininémia (β=4,17, p=0,008) e número total de fármacos administrados (β=-0,46, p<0,001); a evolução da %MG associou-se com força de preensão palmar (β=-0,11, p=0,028), história de toxicodependência (β=-5,75, p=0,024), creatininémia (β=-5,91, p=0,004) e suprimento proteico (β=-0,06, p=0,001); a evolução do IMG associou-se com história de toxicodependência (β=- 2,64, p=0,019), creatininémia (β=-2,86, p<0,001) e suprimento proteico (β=-0,02, p<0,001). A variação relativa (%Δ) desses compartimentos corporais entre T1 e T2 indicou o impacto da terapêutica imunossupressora na composição corporal: o regime baseado na ciclosporina associou-se positivamente com a %Δ do IMM (β=23,76, p<0,001) e %Δ da MCC (β=26,58, p<0,001) e negativamente com a %Δ MG (β=-25,64, p<0,001) e %Δ do IMG (β=-25,62, p<0,001), relativamente ao regime baseado no tacrolimus. Os esteróides não influenciaram a evolução do GER nem com a dos compartimentos corporais. Conclusões: O estado de nutrição, avaliado por ASG, melhorou significativamente após o TH, traduzida pela diminuição da prevalência de desnutrição. O normometabolismo pré-TH foi prevalente e associou-se à menor idade e à desnutrição pré- TH. O hipometabolismo pré-TH associou-se à história de toxicodependência e à sarcopénia pré-TH. O hipermetabolismo pré-TH associou-se ao maior IMM e à etiologia viral da doença hepática. Após o TH, houve normalização progressiva do estado metabólico. Foram identificados três perfis de evolução do GER, associando-se com: peso corporal e suprimento energético na amostra total; peso corporal e contributo energético dos lípidos no grupo hipometabólico pré- TH; e peso corporal e desnutrição pela ASG no grupo normometabólico pré-TH. Foram identificados diferentes perfis de evolução da composição corporal após TH. A evolução do músculo esquelético associou-se positivamente com a força de preensão palmar e a creatininémia e negativamente com o número total de fármacos administrados. A evolução da adiposidade (%MG e IMG) associou-se inversamente com a história de toxicodependência, a creatininémia e o suprimento proteico; adicionalmente, a %MG associou-se inversamente com a força de preensão palmar. O regime baseado na ciclosporina associou-se independentemente com diminuição da adiposidade e aumento do músculo esquelético, comparativamente ao regime baseado no tacrolimus.---------------------------ABSTRACT:Background: The assessment of nutritional status in patients undergoing liver transplantation (LTx) should be comprehensive, accounting for the wide spectrum of the clinical and metabolic conditions. The metabolic disturbances related to liver disease may limit the precision and accuracy of traditional nutritional assessment methods underestimating the undernourishment. After LTx, it is expected that many metabolic derangements improve with the recovery of liver function. However, some metabolic complications arising after LTx, related to nutritional status, hepatic denervation, and prolonged immunosuppression, may compromise the longterm outcome. A reliable longitudinal assessment of both energy metabolism and body compartments after LTx, combined with assessments of other factors potentially affecting the nutritional status, may enable a better interpretation on the relationship between the metabolic and the nutritional status. These reliable assessments may precociously identify nutritional risk conditions and optimize and customize clinical and nutritional strategies improving the prognosis. Objective: To assess longitudinally the nutritional status shortly after orthotopic LTx in patients with chronic liver disease, and identify factors, beyond surgery, determining different energy metabolism and body composition profiles.Methods: A cohort of consecutive patients who underwent LTx due to chronic liver disease was studied within a period of two years. The assessments were performed in three occasions: at the last visit before LTx (T0), after surgery as soon as respiratory and functional autonomy was established (T1), and approximately one month after surgery (T2). On each occasion all assessments were performed on the same day, and included: the dietary assessment by 24- hour dietary recall, nutritional status by the Subjective Global Assessment (SGA), the resting energy expenditure (REE) by indirect calorimetry, anthropometry, body composition by multifrequency bioelectrical impedance analysis, and muscle strength by handgrip strength. Both the lean mass index (LMI) and body cell mass (BCM) were used as surrogates of skeletal muscle, and both the percentage of fat mass (%FM) and fat mass index (FMI) of adiposity. The REE was predicted according to the Harris and Benedict equation. Hypermetabolism was defined as a measured REE more than 120% of the predicted value; normometabolism as a measured REE within 80-120% of the predicted value; and hypometabolism as a measured REE less than 80% of the predicted value. Multiple regression analysis was used: by logistic regression to identify variables associated with odds of belong each pre-LTx metabolic groups; by linear multiple regression analysis to identify variables associated with body compartments relative variations (%Δ) in the post-LTx period; and by mixed effects models to identify variables associated with the REE and body compartments profiles pre- and post-LTx. Results: Fifty six patients with a mean (SD) of 53.7 (8.5) years of age were included, 87.5% were men and 23.2% with alcoholic liver disease. After LTx 60.7% individuals were assigned to tacrolimus-based immunosuppressive regimen. The patients were assessed at a median time (inter-quartil range) of 90.5 (P25 44.2; P75 134.5) days before LTx (T0), at a median time of 9.0 (P25 7.0; P75 12.0) (T1) and 36 (P25 31.0; P75 43.0) (T2) days after LTx. After LTx the nutritional status significantly improved: the SGA-undernourishment decreased from 37.5% (T0) to 16.1% (T2) (p<0.001). Before LTx, 41.1% patients were normometabolic, 37.5% hypometabolic, and 21.4% hypermetabolic. The predictors of each pre-LTx metabolic group were: age (OR=0.899, p=0.010) and SGA-undernourishment (OR=5.038, p=0.015) for the normometabolic group; and LMI (OR=1.264, p=0.049) and viral etiology of liver disease (OR=8.297, p=0.019) for the hypermetabolic group. No multiple model was found for the pre-LTx hypometabolic group, but univariate association was found with history of drug addiction (OR=0.282, p=0.047) and pre- LTx sarcopenia (OR=8.000, p=0.040). After LTx a significant normalization of the metabolic status occurred, indicated by the increase in the prevalence of normometabolic patients (from T0: 41.1% to T2: 57.1%, p=0.040). Different REE profiles were found with REE stratified by preoperative metabolic status: in the hypometabolic group a significant progressive increase in mean REE (Kcal) was observed (T0: 1030.6; T1: 1436.1, p=0.001; T2: 1659.2, p<0.001); in the hypermetabolic group, a significant progressive decrease in mean REE (Kcal) was observed (T0: 2097.1; T1: 1662.5, p=0.024; T2: 1493.0, p<0.001); and in the normometabolic group, no significant differences were found. The REE profiles were associated with: body weight (β- estimate=9.6, p<0.001) and energy intake (β-estimate=13.6, p=0.005) in the whole sample; with body weight (β-estimate=7.1, p=0.018) and %TEV from lipids (β-estimate=18.9, p=0.003) in the hypometabolic group; and with body weight (β-estimate=14.1, p<0.001), and SGAundernourishment (β-estimate=-171, p=0.007) in the normometabolic group. A transient decrease in most body compartments occurred from T0 to T1, with subsequent catch-up to similar preoperative values. Exceptions were the extracellular water, decreasing from T0 to T2 (mean 18.2 L to 17.8 L, p=0.042), the fat mass (mean 25.1 Kg to 21.7 Kg, p<0.001) and FMI (mean 10.6 Kg.m-2 to 9.3 Kg.m-2, p<0.001), decreasing from T1 to T2. Significant predictors of skeletal muscle and adiposity profiles were found: LMI evolution was associated with handgrip strength (β-estimate=0.06, p<0.001), serum creatinine (β- estimate=2.28, p<0.001) and number of medications (β-estimate=-0.21, p<0.001); BCM evolution was associated with handgrip strength (β-estimate=0.16, p<0.001), serum creatinine (β-estimate=4.17, p<0.001) and number of medications (β-estimate=-0.46, p<0.001); the %FM evolution was associated with handgrip strength (β-estimate=-0.11, p=0.028), history of drug addiction (β-estimate=-5.75, p=0.024), serum creatinine (β-estimate=-5.91, p=0.004) and protein intake (β-estimate=-0.06, p=0.001); and FMI evolution was associated with history of drug addiction (β-estimate=-2.64, p=0.019), serum creatinine (β-estimate=-2.86, p<0.001) and protein intake (β-estimate=-0.02, p<0.001). The %Δ of the aforementioned body compartments from T1 to T2 indicated the influence of immunosuppressive agents on body composition: the cyclosporine-based regimen, compared with tacrolimus-based regimen, was positively associated with %Δ LMI (β-estimate=23.76, p<0.001) and %Δ BCM (β- estimate=26.58, p<0.001), and inversely associated with %Δ FM (β-estimate=-25.64, p<0.001) and %Δ FMI (β-estimate=-25.62, p<0.001). No significant changes in REE or body composition were observed associated with dose or duration of steroid therapy. Conclusions: The SGA-assessed nutritional status improved shortly after LTx, with significant decrease in prevalence undernourished individuals. XXI Preoperative normometabolism was prevalent and was associated with younger age and SGAundernourishment before LTx. Preoperative hypometabolism was associated with history of drug addiction and pre-LTx sarcopenia. Preoperative hypermetabolism was associated with higher LMI and viral etiology of liver disease. A significant normalization of the metabolic status was observed after LTx. The REE profiles were positively predicted by body weight and energy intake in the whole sample, by body weight and percentage of energy intake from lipids in the preoperative hypometabolic patients, and by body weight and SGA–undernourishment in the preoperative normometabolic patients. Different body composition profiles were found after LTx. Skeletal muscle profile was positively associated with handgrip strength and serum creatinine, and inversely with the number of medications. The adiposity profile was inversely associated with history of drug addiction, serum creatinine and protein intake. Additionally, the %FM evolution was inversely associated with handgrip strength. The cyclosporine-based regimen, compared with tacrolimus-based regimen, was independently associated with skeletal muscle increase and adiposity decrease.
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OBJECTIVE: To assess intermediate-term outcome in children who have undergone orthotopic heart transplantation. METHODS: We carried out a longitudinal and prospective study between October '92 and June '99 comprising 20 patients with ages ranging from 12 days to 7 years (mean of 2.8 years). We employed a double immunosuppression protocol with cyclosporine and azathioprine and induction therapy with polyclonal antithymocyte serum. Survival and complications resulting from the immunosuppression protocol were analyzed. RESULTS:ACE=Symbol>The double immunosuppression protocol and the induction therapy with polyclonal antithymocyte serum resulted in an actuarial survival curve of 90% and 78.2% at 1 and 6 years, respectively, with a mean follow-up period of 3.6 years. One patient died due to acute rejection 40 days after transplantation; another patient died 2 years after transplantation due to lymphoproliferative disorder; a third patient died because of primary failure of the graft; and a fourth patient died due to bronchopneumonia. The major complications were as follows: acute rejection, infection, nephrotoxicity, and systemic hypertension. The means of rejection and infection episodes per patient were 2.9 and 3.4, respectively. After one year of transplantation, a slight reduction in the creatinine clearance and systemic hypertension were observed in 7 (38.9%) patients. CONCLUSION: Heart transplantation made life possible for those patients with complex congenital heart diseases and cardiomyopathies in refractory congestive heart failure constituting a therapeutical option for this group of patients in the terminal phase.
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Due to the eye's specific anatomical and physiological conformation, the treatment of eye diseases is a real challenge for pharmaceutical therapy. The presence of efficient protective barriers (i.e., the conjunctival and corneal membranes) and protective mechanisms (i.e., blinking and nasolachrymal drainage) makes this organ particularly impervious to local drug therapy. To overcome these issues, numerous strategies have been envisioned using pharmaceutical technology. Many formulations currently on the market or still under development are emulsions or colloidal systems intended to enhance precorneal residence time and corneal penetration, causing a consequent increase in drug bioavailability after instillation. After a review of some recent developments in the field of cyclosporin A formulations for the eye, a novel micellar formulation of cyclosporine A based on a diblock methoxy-poly(ethylene glycol)-hexysubstituted poly(lactides) (MPEG-hexPLA) is described.
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AIMS OF THE STUDY: Analysis of indications and results of paediatric renal transplantation in a single centre, before and after the introduction of cyclosporine A (CSA). METHODS: Historical retrospective study. RESULTS: 19 transplantations were performed in 14 patients (5 second grafts) between 1971 and 1987 (group I). 13 patients were transplanted between 1988 and 1998 (no second transplant) (group II). In group II, all the patients had immunosuppression with CSA, but none in group I. Group II, with CSA, showed better renal survival than patients without CSA. In group I, obstructive uropathies (posterior urethral valves, pyelo-ureteral junction stenosis, vesico-ureteral reflux) represent a common cause (35%) of terminal chronic renal failure (TCRF), whereas in group II they represent only 15% of the causes and chronic glomerulonephritis is the most common cause (69%) of TCRF. Acute and chronic graft rejections were the cause of 9 and 1 graft losses in group I and II respectively. Living related donors account for 14% of all renal transplantations in group I and 46% in group II. CONCLUSIONS: The incidence of paediatric patients referred to Lausanne for TCRF is stable. We have observed a constant and steady decrease in obstructive uropathies leading to TCRF and renal transplantations, whereas glomerulonephritis are increasingly frequent. Graft survival has much improved since the introduction of cyclosporine A, without an increase in morbidity. In carefully selected cases, intrafamilial renal transplantation provides good results and helps to shorten the time spent on dialysis.
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The number of pregnant women receiving immunosuppressants for anti-rejection therapy or autoimmune diseases is increasing. All immunosuppressive drugs cross the placenta, raising questions about the long-term outcome of the children exposed in utero. There is no higher risk of congenital anomalies. However, an increased incidence of prematurity, intrauterine growth retardation (IUGR) and generally low birth weight has been reported, as well as maternal hypertension and preeclampsia. The most frequent neonatal complications are those associated with prematurity and IUGR, as well as adrenal insufficiency with corticosteroids, immunological disturbances with azathioprine and cyclosporine, and hyperkalemia with tacrolimus. The long-term follow-up of infants exposed to immunosuppressants in utero is still limited and experimental studies raise the question whether there could be an increased incidence at adult age of some pathologies including renal insufficiency, hypertension and diabetes.
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Heart transplantation remains the best therapeutic option for the treatment of end-stage heart failure. However, good survival rates can be obtained only if patients are closely monitored, particularly for their immunosuppressive regimens. Currently, a triple-drug regimen usually based on calcineurin-inhibitors (cyclosporin A or tacrolimus), anti-proliferative agents and steroids is used in most recipients. New agents such as the mTOR inhibitors, a more recently developed class of immunosuppressive drugs, can also be used in some patients. The aim of this article is to review currently used immunosuppressive regimens after heart transplantation, and to propose some individualized options depending on specific patient characteristics and recent pharmacological developments in the field.
Mycophenolic acid formulations in adult renal transplantation - update on efficacy and tolerability.
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The description more than 30 years ago of the role of de novo purine synthesis in T and B lymphocytes clonal proliferation opened the possibility for selective immunosuppression by targeting specific enzymatic pathways. Mycophenolic acid (MPA) blocks the key enzyme inosine monophosphate dehydrogenase and the production of guanosine nucleotides required for DNA synthesis. Two MPA formulations are currently used in clinical transplantation as part of the maintenance immunosuppressive regimen. Mycophenolate mofetil (MMF) was the first MPA agent to be approved for the prevention of acute rejection following renal transplantation, in combination with cyclosporine and steroids. Enteric-coated mycophenolate sodium (EC-MPS) is an alternative MPA formulation available in clinical transplantation. In this review, we will discuss the clinical trials that have evaluated the efficacy and safety of MPA in adult kidney transplantation for the prevention of acute rejection and their use in new combination regimens aiming at minimizing calcineurin inhibitor toxicity and chronic allograft nephropathy. We will also discuss MPA pharmacokinetics and the rationale for therapeutic drug monitoring in optimizing the balance between efficacy and safety in individual patients.
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To achieve the goal of sustained donor-specifi c transplantation (Tx) tolerance, research efforts are now focusing on therapies based on specifi c cell subsets with regulatory properties. We and others have previously highlighted the therapeutic potential of naturally occurring CD4+CD25+Foxp3+ regulatory T cells (nTreg) in promoting long-term graft acceptance. Using more stringent experimental Tx models, we were however confronted to limitations. Indeed, while the transfer of antigenspecifi c nTreg promoted long-term MHC-mismatched skin allograft acceptance in lymphopenic mice in the absence of any immunosuppressive drug, allograft survival was only slightly prolonged when nTreg were transferred alone into non-lymphopenic mice. This suggested that in more stringent conditions, adjuvant therapies may be needed to effectively control alloreactive T cells (Teff). Whether and how the expansion of the Treg pool could be best combined with current immunosuppressive regimens in clinical settings remains to be defi ned. In this study, we have used in vitro assays and an in vivo skin Tx model to investigate the effects of various immunosuppressive drugs on the survival, proliferation and effector function of Teff and nTreg in response to alloantigens. Teff proliferation was inhibited in a dose-dependent manner by rapamycin and cyclosporine A, while anti-CD154 mAb only marginally affected Teff survival, proliferation and effector fucntion in vitro. Rapamycin promoted apoptosis of Teff as compared to nTreg that were more resistant in the presence of IL-2. In vivo, the transfer and/or expansion of Treg could be advantageously combined with rapamycin and anti-CD154 mAb treatment to signifi cantly prolong MHC-mismatched skin allografts survival in non-lymphopenic recipients. Taken together our data indicate that immunosuppressive drugs differentially target T-cell subsets and that some regimens could promote Treg expansion while controlling the Teff pool in response to alloantigens.
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Introduction: Apoptosis plays a central role in chronic hepatitis C virus (HCV) infection. Although the activation of cell death signals has been reported, HCV infection persists in most patients suggesting a pro-survival adaptation, eventually developing hepatocellular carcinoma. This study focused on the role of mitochondria in the activation of pro- and antiapoptotic response in cells expressing HCV proteins. Materials and Methods: Human Osteosarcoma U2-OS cells inducibly expressing the HCV polyprotein; huh7.5 hepatoma cells transfected with full length HCV genome. Results: Long term induction of viral proteins in U2-OS cells induced a cyclosporine A-sensitive cytochrome c partial release from mitochondria, revealed by immunofluorescence, western blot and spectral analysis. In HCV-transfected Huh7.5 cells, release of the apoptosis inducing factor (AIF) with no apparent nuclear translocation was also observed. HCV positive cells displayed an HIF-dependent enhanced glycolysis, charachterized by up-regulation of the mitochondria-bound Hexokinase II (HKII); preliminary data on signal transduction pathway revealed the iperphosphorylation of Glycogen synthase kinase 3b(GSK3b). Conclusion: HCV causes a cell stress activating an early apoptotic response, the entity of which likely depends on the cell type. Nevertheless a wide series of cell survival mechanisms are also triggered resulting in a metabolic adaptation possibly favouring carcinogenesis. Based on our results, we propose a pro-survival mechanism linking HCV infection to inhibition of GSK-3b, stabilization of HIF1a and up-regulation of HKII, the last events causing a glycolytic shift and protecting from apoptosis.
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Background: Psoriasis is accepted as a multisystemic disease with several important systemic manifestations. Thus, underlying comorbidities have to be taken into account in the choice of treatment. Objective: To explore the role of anti-TNF therapy in the treatment of psoriasis in a patient with acute-on-chronic pancreatitis. Methods: Here, we present the case of a 75-year-old patient with severe psoriasis also suffering from chronic alcohol-induced pancreatitis with recurrent acute flares. A recent life-threatening episode of acute pancreatitis and ischemic liver precluded the reintroduction of methotrexate. Cyclosporine was also excluded as it has been reported to induce acute pancreatitis. Thus, an anti-TNF treatment was initiated in close collaboration with a gastroenterologist. Results: A year after starting anti-TNF therapy the patient continues to show complete clinical remission of his psoriasis. No side effects, particularly no bacterial infections, were reported. No relapses of the patient's underlying chronic pancreatitis were observed throughout the entire treatment with regular clinical and laboratory monitoring, suggesting that chronic pancreatitis is not per se a contraindication for anti-TNF therapy. Conclusion: This case study opens the way for further questioning on the role of TNF in the pathogenesis of chronic and acute pancreatitis and the use of anti-TNF therapy in its treatment. © 2013 S. Karger AG, Basel.
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The main regulators of leukocyte trafficking during inflammatory responses are chemokines. However, another class of recently identified chemotactic agents is extracellular cyclophilins, the proteins mostly known as receptors for the immunosuppressive drug, cyclosporine A. Cyclophilins can induce leukocyte chemotaxis in vitro and have been detected at elevated levels in inflamed tissues, suggesting that they might contribute to inflammatory responses. We recently identified CD147 as the main signaling receptor for cyclophilin A. In the current study we examined the contribution of cyclophilin-CD147 interactions to inflammatory responses in vivo using a mouse model of acute lung injury. Blocking cyclophilin-CD147 interactions by targeting CD147 (using anti-CD147 Ab) or cyclophilin (using nonimmunosuppressive cyclosporine A analog) reduced tissue neutrophilia by up to 50%, with a concurrent decrease in tissue pathology. These findings are the first to demonstrate the significant contribution of cyclophilins to inflammatory responses and provide a potentially novel approach for reducing inflammation-mediated diseases.
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Some experimental studies have suggested a beneficial effect of the mammalian target of rapamycin (mTOR) inhibitor use on hepatic and renal cyst growth in patients with autosomal dominant polycystic kidney disease (ADPKD). However, the results of clinical studies are conflicting and the role of mTOR inhibitors is still uncertain. We report the case of a patient with ADPKD who underwent deceased kidney transplantation because of an end-stage renal disease. The evolution was uneventful with an excellent graft function under cyclosporine (CsA) monotherapy. Some years later, the patient developed a symptomatic hepatomegaly due to growth of cysts. CsA was replaced by sirolimus, an mTOR inhibitor, in order to reduce or control the increase in the cyst and liver volume. Despite the switch, the hepatic volume increased by 25% in two years. Finally sirolimus was stopped because of the lack of effect on hepatic cyst growth and the presence of sirolimus side effects. The interest of our case resides in the followup by MRI imaging during the mTOR inhibitor treatment and 15 months after the restart of the initial immunosuppressive therapy. This observation indicates that mTOR inhibitors did not have significant effect on cyst-associated hepatic growth in our patient, which is consistent with some results of recent large clinical studies.
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Angiotensin II (Ang II) highly stimulates superoxide anion production by neutrophils. The G-protein Rac2 modulates the activity of NADPH oxidase in response to various stimuli. Here, we describe that Ang II induced both Rac2 translocation from the cytosol to the plasma membrane and Rac2 GTP-binding activity. Furthermore, Clostridium difficile toxin A, an inhibitor of the Rho-GTPases family Rho, Rac and Cdc42, prevented Ang II-elicited O2-/ROS production, phosphorylation of the mitogen-activated protein kinases (MAPKs) p38, extracellular signal-regulated kinase 1/2 (ERK1/2) and c-Jun N-terminal kinase 1/2, and Rac2 activation. Rac2 GTPase inhibition by C. difficile toxin A was accompanied by a robust reduction of the cytosolic Ca(2)(+) elevation induced by Ang II in human neutrophils. Furthermore, SB203580 and PD098059 act as inhibitors of p38MAPK and ERK1/2 respectively, wortmannin, an inhibitor of phosphatidylinositol-3-kinase, and cyclosporin A, a calcineurin inhibitor, hindered both translocation of Rac2 from the cytosol to the plasma membrane and enhancement of Rac2 GTP-binding elicited by Ang II. These results provide evidence that the activation of Rac2 by Ang II is exerted through multiple signalling pathways, involving Ca(2)(+)/calcineurin and protein kinases, the elucidation of which should be insightful in the design of new therapies aimed at reversing the inflammation of vessel walls found in a number of cardiovascular diseases.