Statins in solid organ transplantation: is there an immunosuppressive effect?

Benefits of statin therapy within a year after kidney transplantation

Cardiovascular disease remains a leading cause of morbidity and mortality after kidney transplantation (KT). Although statins reduce cardiovascular risk and have renal benefits in the general population, their effects on KT recipients are not well-established. We studied the effects of early statin use (within 1-year post-transplantation) on long-term outcomes in 714 KT recipients from the Korean cohort study for outcome in patients with KT. Compared with the control group, statin group recipients were significantly older, had a higher body mass index, and had a higher prevalence of diabetes mellitus. During a median follow-up of 85 months, 74 graft losses occurred (54 death-censored graft losses and 20 deaths). Early statin use was independently associated with lower mortality (hazard ratio, 0.280; 95% confidence interval 0.111-0.703) and lower death-censored graft loss (hazard ratio, 0.350; 95% confidence interval 0.198-0.616). Statin therapy significantly reduced low-density lipoprotein cholesterol levels but did not decrease the risk of major adverse cardiovascular events. Biopsy-proven rejection and graft renal function were not significantly different between statin and control groups. Our findings suggest that early statin use is an effective strategy for reducing low-density lipoprotein cholesterol and improving patient and graft survival after KT.

Statins in Kidney Transplant Recipients: Usage, All-Cause Mortality, and Interactions with Maintenance Immunosuppressive Agents

SIGNIFICANCE STATEMENT

Cardiovascular diseases account for 32% of deaths among kidney transplant recipients. Statin therapy is common in this population. However, its effect on mortality prevention remains unclear among kidney transplant recipients, whose clinical risk profile might be unique because of concomitant immunosuppressive therapy. In this national study of 58,264 single-kidney transplant recipients, statin use was associated with a 5% decrease in mortality. More importantly, this protective association was stronger among those who used a mammalian target of rapamycin (mTOR) inhibitor for immunosuppression (27% decrease in mTOR inhibitor users versus 5% in nonusers). Our results suggest that statin therapy may reduce mortality in kidney transplant recipients and that the strength of this protective association may vary by immunosuppression regimen.

BACKGROUND

Cardiovascular diseases are the leading cause of mortality in kidney transplant (KT) recipients, accounting for 32% of deaths. Statins are widely used in KT recipients, but effectiveness for preventing mortality remains unclear in this population, especially because of interaction between statins and immunosuppressive agents. We analyzed a national cohort to assess the real-world effectiveness of statins for reducing all-cause mortality in KT recipients.

METHODS

We studied statin use and mortality among 58,264 adults (18 years or older) who received single kidneys between 2006 and 2016 and had Medicare part A/B/D. Statin use was ascertained from Medicare prescription drug claims and deaths from Center for Medicare and Medicaid Services records. We estimated the association of statin use with mortality using multivariable Cox models, with statin use as a time-varying exposure and immunosuppression regimen as effect modifiers.

RESULTS

Statin use increased from 45.5% at KT to 58.2% at 1-year post-KT to 70.9% at 5-year post-KT. We observed 9785 deaths over 236,944 person-years. Overall, statin use was significantly associated with lower mortality (adjusted hazard ratio [aHR], 0.95; 95% confidence interval [CI], 0.90 to 0.99). The strength of this protective association varied by calcineurin inhibitor use (among tacrolimus users, aHR, 0.97; 95% CI, 0.92 to 1.03 versus among calcineurin nonusers, aHR, 0.72; 95% CI, 0.60 to 0.87; interaction P =0.002), mammalian target of rapamycin (mTOR) inhibitor use (among mTOR inhibitor users, aHR, 0.73; 95% CI, 0.57 to 0.92 versus among nonusers, aHR, 0.95; 95% CI, 0.91 to 1.00; interaction P =0.03), and mycophenolate use (among mycophenolate users, aHR, 0.96; 95% CI, 0.91 to 1.02 versus among nonusers, aHR, 0.76; 95% CI, 0.64 to 0.89; interaction P =0.002).

CONCLUSION

Real-world evidence supports statin therapy for reducing all-cause mortality in KT recipients. Effectiveness might be greater when combined with mTOR inhibitor-based immunosuppression.

Fibrotic plaques in heart transplanted patients and their association with insulin resistance syndrome and Lp(a)

BACKGROUND

Angiographic evidence of cardiac allograft vasculopathy (CAV_angio) is a major limiting factor to survival after heart transplantation (HTx). Prevention of CAV_angio is therefore most relevant. Whether modifiable risk factors could be targeted for the prevention of fibrotic plaques, that are common and related to CAV_angio, is not clear.

METHODS AND RESULTS

In a cohort of 74 consecutive HTx patients (median post-transplant interval 9.2 [4.1-15.5] years), we used the high resolution of optical coherence tomography (OCT) to quantify angulation parameters (maximal and mean arc) and plaque load (mean arc*relative plaque length) of fibrotic plaques. Mean arc was defined as the mean value of all angulation measurements per patient. We assessed the association between cardiovascular risk factors and OCT findings. Linear regression analysis showed a significant association of TG/HDL-c with mean fibrotic arc (12.7 [3.9-21.5], p = 0.006) and fibrotic plaque load (2298 [617-3979], p = 0.009) after adjustment for recipient age and sex. We used the median value of fibrotic plaque load to define high fibrotic plaque load. In binary logistic regression analysis, TG/HDL-c (odds ratio [OR] 1.81 with 95% CI [1.09-3.03], p = 0.02) and Lp(a) (OR 1.02 [1.00-1.05], p = 0.02) were associated with high fibrotic plaque load. Multivariable logistic regression analysis confirmed Lp(a) as significant predictor of high fibrotic plaque load (OR 1.03 [1.01-1.05], p = 0.02).

CONCLUSION

TG/HDL-c ratio, a surrogate of insulin resistance syndrome, and Lp(a) were significantly associated with fibrotic plaque in HTx patients. Insulin resistance syndrome and Lp(a) might therefore represent additional targets for CAV prevention.

A randomized clinical study using optical coherence tomography to evaluate the short-term effects of high-intensity interval training on cardiac allograft vasculopathy: a HITTS substudy

Cardiac allograft vasculopathy (CAV) remains a leading cause of long-term mortality after heart transplantation. Both preventive measures and treatment options are limited. This study aimed to evaluate the short-term effects of high-intensity interval training (HIT) on CAV in de novo heart transplant (HTx) recipients as assessed by optical coherence tomography (OCT). The study population was a subgroup of the 81-patient HITTS study in which HTx recipients were randomized to HIT or moderate intensity continuous training (MICT) for nine consecutive months. OCT images from baseline and 12 months were compared to assess CAV progression. The primary endpoint was defined as the change in the mean intima area. Paired OCT data were available for 56 patients (n = 23 in the HIT group and n = 33 in the MICT group). The intima area in the entire study population increased by 25% [from 1.8±1.4mm² to 2.3±2.0mm² , p<0.05]. The change was twofold higher in the MICT group (0.6±1.2 mm² ) than in the HIT group (0.3±0.6 mm² ). However, the treatment effect of HIT was not significant (treatment effect = -0.3 mm² , 95% CI [-0.825 to 0.2 mm² ] p = 0.29). These results suggest that early initiation of HIT compared with MICT does not attenuate CAV progression in de novo HTx recipients. This article is protected by copyright. All rights reserved.

Effect of HMG CoA reductase inhibitors on the development of chronic lung allograft dysfunction

Lung transplant recipients (LRs) have a reduced median 5-year survival of approximately 55% primarily due to chronic lung allograft dysfunction (CLAD). Statins have anti-inflammatory and immunomodulatory effects that may facilitate CLAD prevention. This study sought to evaluate statin effect on CLAD development. Adult bilateral LRs from January 2004 to October 2013 were included. Statin group included recipients with early statin use and continued for minimum 6 months. Propensity score matching was performed for age, gender, and native lung disease to select matched nonstatin group. Competing risk approach was used to evaluate statin effect on CLAD development at 3 years while controlling for acute rejection and CMV pneumonitis. A total of 130 patients were included in each group. CLAD cumulative incidence at 3 years for statin and nonstatin groups was 20.6% (CI: 11.8%-33.5%) and 22.4% (CI: 12.2%-27.3%). Statin use was not associated with a decreased risk of CLAD (subdistribution hazard ratio [SHR]: 0.93, 95% CI: 0.55-1.59, P = .80) but was associated with a decreased risk of death (SHR: 0.45, CI: 0.22-0.90, P = .024). At 3 years, patient survival was 81.7% in statin group and 68.3% in nonstatin group (P = .012). Statins did not significantly delay the time to development of CLAD in LR but did demonstrate a benefit in patient survival.

Diabetes and other endocrine-metabolic abnormalities in the long-term follow-up of pancreas transplantation

Pancreas transplantation (PTX) has been demonstrated to restore long-term glucose homeostasis beyond what can be achieved by intensive insulin therapy or islet transplants. Moreover, PTX has been shown to decrease the progression of the chronic complications of diabetes. However, PTX patients require chronic use of immunosuppressive drugs with potential side effects. The long-term follow-up of PTX patients demands special care regarding metabolic deviations, infectious complications, and chronic rejection. Diabetes and other endocrine metabolic abnormalities following transplantation are common and can increase morbidity and mortality. Previous recipient-related and donor-related factors, as well as other aspects inherent to the transplant, act together in the pathogenesis of those abnormalities. Early recognition of these disturbances is the key to timely treatment; however, adequate tools to achieve this goal are often lacking. In a way, the type of PTX procedure, whether simultaneous pancreas kidney or not, seems to differentially influence the evolution of endocrine and metabolic abnormalities. Further studies are needed to define the best approach for PTX patients. This review will focus on the most common endocrine metabolic disorders seen in the long-term management of PTX: diabetes mellitus, hyperlipidemia, and bone loss. The authors here cover each one of these endocrine topics by showing the evaluation as well as proper management in the follow-up after PTX.

The role of statins in patients after heart transplantation

Numerous studies have shown that statin therapy initiated early after heart transplantation improves the short- and long-term prognosis, leading to a reduction in the incidence of cardiac allograft vasculopathy (CAV), acute rejection episodes and significantly lowers the incidence of cancer in this patient population. The molecular mechanisms responsible for the beneficial effects of statins in patients after heart transplantation are complex; the effectiveness of statins is associated not only with their hypolipemic action, but also with their pleiotropic properties. Statins have been shown to exert protective and therapeutic effects against cancer because they act as antiproliferative agents, promoting apoptosis and inhibiting angiogenesis. Moreover, they reduce the number of circulating monocytes, which inhibits the secretion of proinflammatory cytokines, growth factors, adhesion molecules, chemokines, and matrix metalloproteinases, preventing chronic rejection and CAV. For these reasons, statins should be used as part of standard therapy in patients after heart transplantation.

Cardiac allograft vasculopathy: a donor or recipient induced pathology?

Cardiac allograft vasculopathy (CAV) is one of the main causes of late-stage heart failure after heart transplantation. CAV is characterized by concentric luminal narrowing of the coronary arteries, but the exact pathogenesis of CAV is still not unraveled. Many researchers show evidence of an allogeneic immune response of the recipient, whereas others show contrasting results in which donor-derived cells induce an immune response against the graft. In addition, fibrosis of the neo-intima can be induced by recipient-derived circulating cells or donor-derived cells. In this review, both donor and recipient sides of the story are described to obtain better insight in the pathogenesis of CAV. Dual outcomes were found regarding the contribution of donor and recipient cells in the initiation of the immune response and the development of fibrosis during CAV. Future research could focus more on the potential synergistic interaction of donor and recipient cells leading to CAV.

Is liver transplantation a risk factor for cardiovascular disease? A meta-analysis of observational studies

Up to two-thirds of patients develop metabolic syndrome within the first 5 years after orthotopic liver transplantation (OLT). However, data on overall cardiovascular (CV) morbidity and mortality among OLT recipients and particularly those who develop metabolic syndrome remain elusive. A literature search using MEDLINE, the Cochrane Central Register of Controlled Trials, the Cochrane Database of Systematic Reviews, and meeting abstracts (along with their bibliographies) was performed to identify studies. Data on ischemic CV events were extracted from each study and were used for pooled analyses. Overall pooled estimates and 95% confidence intervals (CIs) for the incidence of CV events and deaths were obtained with a random effects model. Twelve observational studies reporting CV outcomes for 4792 post-OLT recipients who were followed for 28,783 person-years were included. Pooled estimates showed that the 10-year risk of developing CV events among the post-OLT recipients was 13.6% (95% CI = 9%-8.1%). Pooled estimates from case-control studies showed that the post-OLT group had an approximately 64% greater risk of experiencing CV events than controls (standardized incidence ratio = 1.64, 95% CI = 1.18-2.20). Among OLT recipients, those with metabolic syndrome were approximately 4 times more likely to have a CV event [odds ratio (OR) = 4.01, 95% CI = 1.94-8.32] without any significant increase in all-cause mortality (OR = 1.15, 95% CI = 0.63-2.10). In conclusion, this systematic review suggests that OLT recipients and particularly those with metabolic syndrome have a high risk for CV events. However, the literature is limited and lacks high-quality studies. Future prospective studies are warranted to confirm these findings and determine whether aggressive risk-reduction strategies can attenuate the increased CV risk seen in this population.

Statins and the risk of cancer after heart transplantation

BACKGROUND

Although newer immunosuppressive agents, such as mTOR (mammalian target of rapamycin) inhibitors, have lowered the occurrence of malignancies after transplantation, cancer is still a leading cause of death late after heart transplantation. Statins may have an impact on clinical outcomes beyond their lipid-lowering effects. The aim of the present study was to delineate whether statin therapy has an impact on cancer risk and total mortality after heart transplantation.

METHODS AND RESULTS

A total of 255 patients who underwent heart transplantation at the University Hospital Zurich between 1985 and 2007 and survived the first year were included in the present study. The primary outcome measure was the occurrence of any malignancy; the secondary end point was overall survival. During follow-up, a malignancy was diagnosed in 108 patients (42%). The cumulative incidence of tumors 8 years after transplantation was reduced in patients receiving a statin (34% versus 13%; 95% confidence interval, 0.25-0.43 versus 0.07-0.18; P<0.003). Statin use was associated with improved cancer-free and overall survival (both P<0.0001). A Cox regression model that analyzed the time to tumor formation with or without statin therapy, adjusted for age, male sex, type of cardiomyopathy, and immunosuppressive therapy (including switch to mTOR inhibitors or tacrolimus), demonstrated a superior survival in the statin group. Statins reduced the hazard of occurrence of any malignancy by 67% (hazard ratio, 0.33; 95% confidence interval, 0.21-0.51; P<0.0001).

CONCLUSIONS

Although it is not possible to adjust for all potential confounders because of the very long follow-up period, this registry suggests that statin use is associated with improved cancer-free and overall survival after cardiac transplantation. These data will need to be confirmed in a prospective trial.

The Emerging Role of TLR and Innate Immunity in Cardiovascular Disease

Cardiovascular disease is a complex disorder involving multiple pathophysiological processes, several of which involve activation of toll-like receptors (TLRs) of the innate immune system. As sentinels of innate immunity TLRs are nonclonally germline-encoded molecular pattern recognition receptors that recognize exogenous as well as tissue-derived molecular dangers signals promoting inflammation. In addition to their expression in immune cells, TLRs are found in other tissues and cell types including cardiomyocytes, endothelial and vascular smooth muscle cells. TLRs are differentially regulated in various cell types by several cardiovascular risk factors such as hypercholesterolemia, hyperlipidemia, and hyperglycemia and may represent a key mechanism linking chronic inflammation, cardiovascular disease progression, and activation of the immune system. Modulation of TLR signaling by specific TLR agonists or antagonists, alone or in combination, may be a useful therapeutic approach to treat various cardiovascular inflammatory conditions such as atherosclerosis, peripheral arterial disease, secondary microvascular complications of diabetes, autoimmune disease, and ischemia reperfusion injury. In this paper we discuss recent developments and current evidence for the role of TLR in cardiovascular disease as well as the therapeutic potential of various compounds on inhibition of TLR-mediated inflammatory responses.

HMG-CoA reductase inhibitors in kidney transplant recipients receiving tacrolimus: statins not associated with improved patient or graft survival

Background

The beneficial effects of early statin use in kidney transplant recipients, especially those on tacrolimus-based immunosuppression, are not well established. We evaluated the predictors of statin use following kidney transplantation and examined its association with patient and allograft survival.

Methods

We examined 615 consecutive patients who underwent kidney transplant at our institution between January 1998 and January 2002. Statin use was assessed at baseline and 3, 6, 9, and 12 months following kidney transplant. Patients were followed for allograft and patient survival.

Results

36% of the 615 kidney transplant recipients were treated with statin treatment. Statin use increased over the course of the study period. Older age, elevated body mass index, higher triglyceride levels, hypercholesterolemia, diabetes, history of myocardial infarction were associated with higher rates of statin use; elevated alkaline phosphatase levels and CMV IgG seropositivity were associated with less statin use. Older age, elevated BMI and hypercholesterolemia remained significant predictors of increased statin use after accounting for covariates using multiple regression. The early use of statins was not associated with improvements in unadjusted patient survival [HR 0.99; 95%CI 0.72-1.37] or graft survival [HR 0.97; 95% CI 0.76-1.24]. The risks of death and graft survival were not consistently reduced with exposure to statin using either adjusted models or propensity scores in Cox Proportional Hazards models.

Conclusions

In a kidney transplant population primarily receiving tacrolimus-based immunosuppression, early statin use was not associated with significantly improved graft or patient survival.

PPARalpha ligand WY14643 reduced acute rejection after rat lung transplantation with the upregulation of IL-4, IL-10 and TGFbeta mRNA expression

BACKGROUND

The peroxisome proliferators-activated receptor-alpha (PPARalpha) is important in lipid metabolism and regulation of inflammation. Recent studies have demonstrated the immunoregulatory effects of PPARalpha. This investigated the immunosuppressive effects of PPARalpha using its ligand, WY14643, on acute lung allograft rejection in a rat model and its mechanism of action.

METHOD

The left lungs were transplanted orthotopically from Brown-Norway donors to F344 recipients. The recipients were then divided into control and WY14643 treatment groups. The allograft rejection was evaluated by daily chest X-ray imaging and was evaluated histologically on Day 7 after transplantation. The cytokine messenger RNA (mRNA) expression at Days 3 and 5 were also evaluated in allografts and recipient spleens.

RESULTS

The radiologic and histologic findings indicated that treatment with the WY14643 reduced acute allograft rejection. WY14643 also significantly extended the allograft survival time. This amelioration of acute rejection by WY14643 was also associated with up-regulated interleukin (IL)-4, IL-10, and transforming growth factor-beta (TGFbeta) mRNA expression in the lung allografts and spleens.

CONCLUSION

This study demonstrated that the administration of the PPARa ligand, WY14643, ameliorates acute lung allograft rejection in rats. Treatment with WY14643 reduced histopathologic scores, prolonged graft survival, and up-regulated the expression of anti-inflammatory cytokine IL-4, IL-10, and TGFbeta mRNA compared with the control.

Aftercare for patients with transplanted organs

BACKGROUND

The postoperative management following solid organ transplantation requires close cooperation between family doctors, internists, the local hospital, and the transplant center.

METHODS

Selective analysis of current national and international guidelines and relevant review articles.

RESULTS/CONCLUSION

In the early phase post transplantation, aftercare involves inpatient treatment and outpatient or inpatient rehabilitation with the aim of complete social and professional reintegration. Early diagnosis and treatment of typical general complications such as post-transplant diabetes, hyperlipidemia, arterial hypertension, osteoporosis, and kidney failure is essential. Early detection and treatment of malignant disease and opportunistic infections in patients with long-term immunosuppression is desirable. Moreover, organ-specific factors have to be taken into account. In the event of transplant dysfunction, recurrence of the underlying disease in the transplant, chronic or acute rejection, and organ-specific infections and drug toxicity have to be considered.

Statins induce immunosuppressive effect on heterotopic limb allografts in rat through inhibiting T cell activation and proliferation

Long-term use of immunosuppressive agents could bring many side effects. Recently, 3-Hydroxy-3-methyl-gutaryl coenzyme A reductase inhibitors (statins) have been reported to be immunomodulatory besides lowering serum cholesterol level. The aim of this study was to investigate the effects of statins on composite tissue allografts and T lymphocyte in vivo and in vitro. Rats were divided into 5 groups: syngeneic transplantation group (Lewis-Lewis); allogeneic control group (Brown Norway-Lewis, no treatment); low-dose statins group (15 mg /kg); high-dose statins group (30 mg /kg) and cyclosporin A group. In vivo, treatment of statins significantly prolonged allografts survival as compared to control group. Histological findings further supported these clinical results and demonstrated less extent of rejection. Immunohistochemical analysis showed that there was a remarkably reduced T cells infiltration in statins groups. Moreover, the serum levels of IL-2 and IFN-gamma were decreased after statins therapy, while these in control group increased significantly. Meanwhile, transcriptional activities of IL-2 and IFN-gamma were also dramatically down-regulated after statins treatment. In vitro, mixed lymphocyte reaction assay was performed and the results revealed lymphocyte proliferation was inhibited by statins in a dose-dependent manner. Furthermore, administration of statins exhibited inhibitory effects on CD3/CD28 mediated T cell activation and proliferation. Besides, the results demonstrated that statins significantly down-regulated mRNA expression and suppress cytokine production of IL-2 and IFN-gamma in vitro. In conclusion, our data demonstrated that application of statins could induce immunosuppressive effect and prolong allografts survival through inhibiting activation and proliferation of T cell and reducing production of IL-2 and IFN-gamma.

Amelioration of human allograft arterial injury by atorvastatin or simvastatin correlates with reduction of interferon-gamma production by infiltrating T cells

BACKGROUND

Graft arteriosclerosis (GA) is an important factor limiting long-term outcomes after organ transplantation. We have used a chimeric humanized mouse system to model this arteriopathy in human vessels, and found that the morphologic and functional changes of experimental GA are interferon (IFN)-gamma dependent. This study evaluated whether 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors, described as inhibitors of IFN-gamma production, affect GA in our model.

METHODS

C.B.-17 severe combined immunodeficiency-beige mice were transplanted with human artery segments as aortic interposition grafts and inoculated with allogeneic human peripheral blood mononuclear cells (PBMCs) or replication-deficient adenovirus encoding human IFN-gamma. Transplant arteries were analyzed from recipients treated with vehicle vs. atorvastatin or simvastatin at different doses. The effects of statins on T-cell alloresponses to vascular endothelial cells were also investigated in vitro.

RESULTS

Graft arteriosclerosis-like arteriopathy induced by PBMCs was reduced by atorvastatin at 30 mg/kg/day or simvastatin at 100 mg/kg/day that correlated with decreased graft-infiltrating CD3+ T cells. Circulating IFN-gamma was also reduced, as were graft IFN-gamma and IFN-gamma-inducible chemokine transcripts and graft human leukocyte antigen-DR expression. Graft arteriosclerosis directly induced by human IFN-gamma in the absence of human PBMCs was also reduced by atorvastatin, but only at the highest dose of 100 mg/kg/day. Finally, atorvastatin decreased the clonal expansion and production of interleukin-2, but not IFN-gamma, by human CD4+ T cells in response to allogeneic endothelial cells in coculture.

CONCLUSIONS

Our results suggest that a benefit of statin administration in transplantation may include amelioration of GA primarily by inhibiting alloreactive T-cell accumulation and consequent IFN-gamma production and secondarily through suppression of the arterial response to IFN-gamma.

Atorvastatin down-regulates the primate cellular response to porcine aortic endothelial cells in vitro

Using mixed lymphocyte reaction (MLR), the effect of atorvastatin on proliferation of human and baboon peripheral blood mononuclear cells (PBMCs) and human CD4+ T cells in response to wild-type (WT) and alpha-1,3-galactosyltransferase gene-knockout (GTKO) porcine aortic endothelial cells (pAECs) was investigated. swine leukocyte antigen class-II (SLA II) expression on pAEC before and after porcine interferon gamma (pIFN-gamma) stimulation, and the effect of atorvastatin on this expression was assessed. Added to the MLR, atorvastatin reduced (i) the human PBMC response to unstimulated (P<0.05) and (ii) the human and baboon PBMC responses to stimulated (P<0.05) WT and GTKO pAEC. Atorvastatin treatment of human PBMC before MLR reduced their response to stimulated WT (P<0.05) and GTKO (P<0.05) pAEC. Stimulation of pAEC with pIFN-gamma increased SLA II expression 20- to 60-fold, which was down-regulated by atorvastatin. Atorvastatin treatment of stimulated pAEC before MLR reduced proliferation of human PBMC (P<0.05) and CD4+ T cells (P<0.05). Atorvastatin down-regulates the primate cellular xenoresponse, possibly through its antiproliferative effect on PBMCs and the reduction of SLA II on pAECs.

Amelioration of myocarditis by statin through inhibiting cross-talk between antigen presenting cells and lymphocytes in rats

Statins, inhibitors of 3-hydroxy-3-methylglutary-coenzyme A (HMG-CoA) reductase, have been recognized as a new type of immunomodulator and reported to have anti-inflammatory effect. To investigate the effect of simvastatin, a lipophilic statin, on myocarditis, we explored whether simvastatin is able to inhibit experimental autoimmune myocarditis (EAM) and adoptive transfer of EAM in rats. We found that administration of simvastatin not only interfered with the development of EAM, but also inhibited the transfer. Antigen presenting cells (APCs) were proved to be important for the development of EAM. The ability of myocarditic splenocytes to transfer myocarditis was enhanced after co-culture with APCs. During co-culture of the myocarditic splenocytes and the APCs, simvastatin not only decreased percentages of CD28 expression in CD4-positive myocarditic splenocytes, and CD80 and CD86 expressions in APCs, but also inhibited the production of tumor necrosis factor (TNF)-partial differential in the CD4-positive myocarditic splenocytes and the APCs. These results indicate that simvastatin was able to ameliorate EAM through the inhibition of cross-talk between lymphocytes and APCs, suggesting beneficial role of simvastatin in the treatment of autoimmune myocarditis.

Incidence of adverse events with HMG-CoA reductase inhibitors in liver transplant patients

Transplant patients are at increased risk of developing dyslipidemia, which contributes to coronary artery disease and cardiovascular events. The purpose of this study was to explore documented adverse effects of liver transplant recipients receiving lipid-lowering therapies.

METHODS

A retrospective chart review of 69 liver transplant patients was conducted to evaluate the incidence of adverse effects, especially rhabdomyolysis and liver function abnormalities, in liver transplant patients treated with a lipid lowering agent (LLA). Data were collected from the time of initiation of LLA to 12 months later, looking at the type, dose, and duration of LLA, concurrent cytochrome P450 inhibitors, immunosuppression used, and laboratory parameters.

RESULTS

For HMG-CoA reductase inhibitor therapy, simvistatin was used in five (7.8%) patients, pravastatin in 40 (62.5%), fluvastatin in one (1.6%), atorvastatin in five (7.8%), and lovastatin in three (4.7%). Gemfibrozil, a fibric acid derivative, was employed as monotherapy in 10 (15.6%) of patients. There were five patients who received combination therapy with a fibric acid derivative, four (80%) with gemfibrozil + pravastatin, and one (20%) with gemfibrozil + simvastatin. Six patients studied had adverse effects, five (7.2%) with myalgia and one (1.4%) with myopathy. LLA monotherapy with either pravastatin or atorvastatin was used in these patients. The five patients with myalgia were on concurrent therapy with cyclosporin, and the patient with myopathy was on concurrent cyclosporin + diltiazem therapy, both of which are P450 inhibitors. One out of 23 patients on a non-immunosuppressant P450 inhibitor developed adverse effects. No significant elevation of alanine aminotransferase, aspartate aminotransferase, or alkaline phosphatase was noted in any patient.

CONCLUSIONS

Overall, there was a general tolerability with a low incidence of adverse events, no incidence of severe complications, and no alterations in liver function tests in the study population with the use of LLA.

Hyperlipidemia is associated with accelerated chronic kidney disease progression after lung transplantation

Hyperlipidemia is associated with faster progression of chronic kidney disease (CKD) in the general public. We sought to investigate this association after lung transplantation. Data was retrospectively collected on 230 lung recipients transplanted between January 1997 and December 2003. Estimated glomerular filtration rates (eGFR) and lipid levels were recorded at regular intervals posttransplant. Independent associations between lipid levels early posttransplant and pertinent renal endpoints were investigated. Baseline LDL was 110 +/- 35 mg/dL and remained unchanged at 6 months. A faster decline in eGFR was seen in those with 6 month LDLs > versus < the mean level of 110 mg/dL (p = 0.05). By 6 months posttransplant eGFRs were lower in the 6 month LDL > versus < 110 mg/dL group (53 +/- 23 vs. 62 +/- 29 mL/min/1.73 m2, p = 0.01), a difference that persisted at 60 months (39 +/- 24 vs. 73 +/- 57 mL/min/1.73 m2, p = 0.05). On univariate analysis, a 6 month LDL in the highest quartile, i.e. >140 mg/dL, predicted faster progression to CKD, defined as declining to an eGFR < 30 mL/min/1.73 m2 (HR 1.5, p = 0.01). This finding persisted in the multivariate Cox-proportional model (HR 1.4, p = 0.02). Hyperlipidemia predicts faster decline in renal function after lung transplant. Prospective trials are needed to confirm this finding.

Low HDL-C predicts the onset of transplant vasculopathy in pediatric cardiac recipients on pravastatin therapy

The levels and protein/lipid compositions of major lipoprotein particles of 19 pediatric cardiac transplant recipients (4-18 yr of age) were studied in this prospective, open clinical follow-up study before and at one yr of pravastatin therapy (10 mg/day). The recipients were grouped into those with (n = 6; group A) and those without (n = 13; group B) angiographically detectable vasculopathy. Twenty-one pediatric non-transplant controls were studied at baseline. At baseline, the group A recipients had 29% lower HDL-C concentrations (p = 0.031) and 29% higher apoB-100/apoA-I ratios (p = 0.034) than the group B recipients. At one yr of pravastatin, the respective figures were 29% (p = 0.013) and 33% (p = 0.005). Compared with the healthy pediatric controls, the transplant recipients had significantly higher serum TG before pravastatin [median (range): 1.3 mmol/L (0.6-3.2) vs. 0.7 mmol/L (0.3-2.4), p = 0.0002] and at one yr [1.3 mmol/L (0.5-3.5) vs. 0.7 mmol/L (0.3-2.4), p = 0.0004]. The baseline apoB-100/apoA1 ratios of the recipients were 33% higher (p = 0.005). In conclusion, low HDL-C and high apoB-100/apoA-I ratio were associated with angiographically detectable vasculopathy. Even though pravastatin effectively lowered the TC and LDL-C and improved compositional properties of LDL and HDL(2) particles, it failed to normalize the elevated TG and, in some patients, to prevent the progression of transplant vasculopathy.

Protective effects of atorvastatin on chronic allograft nephropathy in rats

OBJECTIVE

Chronic allograft nephropathy (CAN) is the leading cause of late kidney allograft loss. Recent studies have suggested that atorvastatin (ATO) may interact with the acute inflammatory process in the renal interstitium and suppress the proliferation of mesangial cells. We hypothesized that ATO could also inhibit the chronic inflammatory process and prevent the progression of CAN.

MATERIALS AND METHODS

Fisher (F344) kidneys were orthotopically transplanted into Lewis rat recipients. Lewis-to-Lewis rat kidney transplantation was served as the syngeneic control (Syn group). Allograft recipients were randomized and treated with cyclosporine A alone (Allo group) or in combination with ATO (15 or 30 mg/kg/d intrgastric, respectively, the low dose treatment group/high dose treatment group [LT/HT] groups). Renal function and the urine protein excretion were analyzed. Animals were sacrificed 20 weeks posttransplantation for histological and immunohistochemical studies, as well as analysis of mRNA levels of cytokines and chemokines.

RESULTS

Renal function progressively deteriorated and substantial proteinuria developed in the Allo group compared with the Syn group. ATO-treated rats had significantly higher creatinine clearance rate and less amount of proteinuria. Histological examination revealed obvious features of CAN in the Allo group, whereas LT/HT groups demonstrated minimal glomerulosclerosis, interstitial fibrosis, intimal thickening, and tubular atrophy. The numbers of infiltrating mononuclear cells (ED1+, CD8+, and CD68+) decreased markedly, and the intragraft expression of transforming growth factor beta1 (TGF-beta1) and collagen III were also significantly attenuated in the LT/HT groups, as compared with the Allo group. The mRNA levels of proinflammatory cytokines (interleukin-2, interferon-gamma, interleukin-10), chemokines (RANTES, MCP-1), and profibrotic genes (TGF-beta1, collagen III) were significantly down-regulated in ATO-treated rats.

CONCLUSION

Atorvastatin showed excellent favorable effects on blocking renal inflammation and fibrosis, and thus, efficiently inhibited the development and progression of CAN, which might improve the long-term survival rate of renal allografts.

Treatment of Hypercholesterolemia With Ezetimibe in Cardiac Transplant Recipients

The purpose of this study was to examine the efficacy and tolerability of ezetimibe in cardiac transplant recipients who were intolerant of 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) or unable to reach target lipid levels with statin therapy. After treatment with ezetimibe (n = 16), mean total and low-density lipoprotein cholesterol levels decreased significantly (228 +/- 40 mg/dl to 197 +/- 48 mg/dl, p = 0.003; and 149 +/- 34 mg/dl to 117 +/- 39 mg/dl, p < 0.001, respectively). One patient required a reduction in ezetimibe dose owing to myalgias; no other adverse events occurred. This initial experience indicates that ezetimibe is well tolerated in cardiac transplant recipients and is effective in reducing total and low-density lipoprotein cholesterol levels.

Long-term patient survival: strategies to improve overall health

The use of potent immunosuppressant therapy has led to an increase in number of patients with successful long-term kidney transplants. These individuals come to kidney transplantation with varying levels of comorbidity associated with end-stage renal disease and are susceptible to immunologic and nonimmunologic comorbidities that arise late after transplantation, including cardiovascular disease, infection, malignancy, and bone disease, which negatively impact on patient and graft survival. In addition, nonadherence to immunosuppressant regimens increases with time after transplantation, which further augments the risk for late-term graft failure and mortality. Consistent and frequent follow-up of kidney transplant recipients beyond the first year permits early diagnosis and successful treatment of many posttransplantation comorbidities. Implementation of preventive practices and aggressive management of risk factors throughout the life of the transplant improves overall health and long-term outcomes. Establishment and maintenance of close relationships among transplant centers, physicians, patients, and their families improves patient adherence to medications and reduces the risk for morbidity and mortality.

Statin therapy in patients with chronic kidney disease: to use or not to use

Dyslipdemia is a common complication of chronic kidney disease (CKD) and contributes to high cardiovascular morbidity and mortality of CKD patients. Experimental studies have demonstrated that lipids induce glomerular and tubulointerstitial injury and that lipid-lowering treatments ameliorate renal injury. Therapy with statins not only has the potential to lower cardiovascular morbidity and mortality in patients with CKD but also to slow progression of renal disease. Whereas the guidelines for treatment of hyperlipidaemia in nonrenal patients are based on prospective, randomized, placebo-controlled mega-trials, such data are not available for CKD patients. This review outlines the limited information currently available on the effect of statins among patients with CKD and summarizes the ongoing randomized trials designed to address this question.

T Cell Costimulation in the Development of Cardiac Allograft Vasculopathy

Cardiac allograft vasculopathy (CAV) is a form of coronary arterial stenosis and a leading cause of death in patients who survive beyond the first year after heart transplantation. Histopathologically, this lesion is concentric diffuse intimal hyperplasia of the arterial wall that is accompanied by extensive infiltration of inflammatory cells, including T cells. Many studies have explored the potential risk factors related to this arterial lesion and its pathogenesis. Continuous minor endothelial cell damage evokes inflammatory processes including T cell activation. Costimulatory molecules play crucial roles in this T cell activation. Many costimulatory pathways have been described, and some are involved in the pathogenesis of CAV, atherogenesis, and subsequent plaque formation. In this review, we summarize the present knowledge of the role of these pathways in CAV development and the possibility of manipulating these pathways as a means to treat heart allograft vascular disease and atherosclerosis.

Immunosuppression for heart transplantation: where are we now?

The success of cardiac transplantation is largely attributable to the development of effective immunosuppressive regimens. The introduction of calcineurin inhibitors was pivotal in reducing the frequency of acute rejection and improving early survival. Newer agents, including mycophenolate mofetil (MMF) and proliferation-signal inhibitors, have shown promise in further reducing acute-rejection rates and, notably, reducing the frequency of cardiac allograft vasculopathy, which limits long-term graft survival. The introduction of first-year intravascular ultrasonography results as a surrogate marker for outcome after cardiac transplantation has helped assessment of the efficacy of immunosuppressive medications. Proliferation-signal inhibitors and MMF were shown by this imaging method to reduce cardiac allograft vasculopathy. The combination of these drugs, in tandem with the weaning of patients off calcineurin inhibitors, has been shown to reverse calcineurin-inhibitor-related nephrotoxic effects. A randomized trial that compared three of the more common immunosuppressive regimens suggested that tacrolimus and MMF are associated with a reduction in the frequency of rejection episodes that require treatment and have the fewest adverse effects. Finally, the use of statins has brought added benefit to immunosuppressive regimens by improving outcomes after cardiac transplantation, reportedly because of an immunomodulatory property. Promising newer immunosuppressive agents await clinical trials. This review presents an overview of the emerging data on immunosuppressive therapy for cardiac transplantation.

Cardio-ankle vascular index (CAVI) for the monitoring of the atherosclerosis after heart transplantation

Atherosclerosis has been reported to progress rapidly after heart transplantation. A quantitative diagnosis is required for the diagnosis of atherosclerosis after heart transplantation. In this study, we compared brachial-ankle pulse wave velocity (baPWV) and cardio-ankle vascular index (CAVI) for the diagnosis. The average values of both baPWV and CAVI in the seven cases after heart transplantation were found to be signif-icantly large in comparison to the average values of the normal healthy people of the same age group. When comparisons were made before and after the heart transplantation in a particular case, CAVI was stable and baPWV changed sharply. A lot of parameters such as blood pressure, blood volume, etc. have been reported to influence baPWV. The results of this study suggested that CAVI was a stable parameter in comparison to baPWV even after heart transplantation. Thus, CAVI may be useful in the diagnosis of arteriosclerosis after heart transplantation.

Effet de la fluvastatine sur l'expression du CMH de classe I par les cellules endothéliales humaines

Originally designed to target elevated lipids, the "traditional" cause of atherosclerosis, statins might also confer vascular benefit by directly or indirectly modulating both the inflammatory and immune responses. Statins have been shown to downregulate MHC class II and CD40 expression on activated endothelial cells (EC). In this study, we investigate the potential effect of statins on MHC class I expression and regulation in response to IFNgamma. Primary cultures of human ECs have been treated with increasing doses of fluvastatin (0.01; 0.1 and 1 microM) with or without IFNgamma for 48 hours. Surface expression of MHC class I and class II has been analyzed by flow cytometry. Our data indicate that fluvastatin increases MHC class I expression on quiescent ECs by a dose-dependent effect. Furthermore, fluvastatin potentiates the MHC class I upregulation but prevents MHC class II induction triggered by IFNgamma. These effects are reversed by mevalonate. In conclusion, our results suggest that while decreasing MHC class II expression, fluvastatin (at 0.1 and 1 microM) upregulates MHC class I expression on ECs. Functional consequences of statin-mediated modulation of MHC on ECs have still to be elucidated in vitro and in vivo.

Current understanding and management of allograft vasculopathy

Cardiac allograft vasculopathy (CAV) is the major obstacle to long-term survival after heart transplantation. It is a rapidly progressive, obliterative form of coronary vasculopathy distinct from classic atheromatous disease. The pathogenesis is most likely multifactorial and involves both alloantigen dependent and independent mechanisms. Since there is no definitive treatment for CAV and new immunosuppressive agents can only slow the progression of this disease, the prophylaxis and modification of numerous risk factors remains the foundation of posttransplant management in the heart transplant recipient. In this review, we discuss current understanding of the pathogenesis of CAV, novel diagnostic and therapeutic avenues and explore optimal approaches to risk factors modification.

The statins--therapeutic diversity in renal disease?

PURPOSE OF REVIEW

Statins significantly reduce cholesterol synthesis and reduce cardiovascular morbidity and mortality. In addition, they appear to have beneficial effects independent of their ability to lower cholesterol. Recent publications suggesting a potential role for statin therapy in chronic renal insufficiency, hypertension and following organ transplantation are reviewed.

RECENT FINDINGS

Pharmacokinetic studies have shown statins to be well-tolerated and effective in patients on long-term haemodialysis, providing equivalent control of lipid levels to that seen in matched controls. Preliminary clinical trials suggest that statins may have beneficial disease-modifying effects in chronic inflammatory disease. Furthermore, immunosuppressive and immunomodulatory actions may confer benefit following cardiac transplantation, but this remains to be demonstrated definitively in renal transplant patients. Data to date suggest that, in addition to reduction of cardiovascular risk, statins may help slow the progress of chronic renal insufficiency, particularly in patients with proteinuria. Addition of statin therapy may also contribute to the control of systemic and pulmonary hypertension.

SUMMARY

Encouraging data in support of a wider spectrum of use for statins are emerging. In addition to reduction of cardiovascular risk through lipid lowering, they may represent an important adjunctive therapy in patients with chronic kidney diseases and post-transplantation. However, further large, well-designed clinical trials are required before their widespread use can be recommended in this setting.

The "Statinth" wonder of the world: a panacea for all illnesses or a bubble about to burst

After the introduction of statins in the market as effective lipid lowering agents, they were shown to have effects other than lipid lowering. These actions were collectively referred to as 'pleiotropic actions of statins.' Pleiotropism of statins formed the basis for evaluating statins for several indications other than lipid lowering. Evidence both in favour and against is available for several of these indications. The current review attempts to critically summarise the available data for each of these indications.