Immunosuppressive agents in multiple sclerosis

Comparative effectiveness of dimethyl fumarate versus non-specific immunosuppressants: Real-world evidence from MSBase

Background

The use of non-specific immunosuppressants (NSIS) to treat multiple sclerosis (MS) remains prevalent in certain geographies despite safety concerns, likely due to resource limitations.

Objective

To use MSBase registry data to compare real-world outcomes in adults with relapsing-remitting MS (RRMS) treated with dimethyl fumarate (DMF) or NSIS (azathioprine, cyclosporine, cyclophosphamide, methotrexate, mitoxantrone or mycophenolate mofetil) between January 1, 2014 and April 1, 2022.

Methods

Treatment outcomes were compared using inverse probability of treatment weighting (IPTW) Cox regression. Outcomes were annualized relapse rates (ARRs), time to discontinuation, time to first relapse (TTFR) and time to 24-week confirmed disability progression (CDP) or 24-week confirmed disability improvement (CDI; in patients with baseline Expanded Disability Status Scale [EDSS] score ≥2).

Results

After IPTW, ARR was similar for DMF (0.13) and NSIS (0.16; p = 0.29). There was no difference in TTFR between cohorts (hazard ratio [HR]: 0.98; p = 0.84). The DMF cohort experienced longer times to discontinuation (HR: 0.75; p = 0.001) and CDP (HR: 0.53; p = 0.001), and shorter time to CDI (HR: 1.99; p < 0.008), versus the NSIS cohort.

Conclusion

This analysis supports the use of DMF to treat patients with relapsing forms of MS, and may have implications for MS practices in countries where NSIS are commonly used to treat RRMS.

Network pharmacology-based analysis of the role of tacrolimus in liver transplantation

Background

Tacrolimus is a powerful immunosuppressant and has been widely used in organ transplantation. In order to further explore the role of tacrolimus in liver transplantation, we conducted network pharmacology analysis.

Methods

GSE100155 was obtained from the GEO database, and the DEGs of liver transplantation were analyzed. The 2D structure of tacrolimus was obtained from the National Library of Medicine, and the pharmacophore model of tacrolimus was predicted using the online tool pharmmapper. Then a network of tacrolimus and target genes was constructed through network pharmacology, and visualization and GO enrichment analysis was performed through Cytoscape. In addition, we also analyzed the correlation between key genes and immune infiltrating cells. The data of GSE84908 was used to verify the changes of key gene expression levels after tacrolimus treatment.

Results

The results of network pharmacological analysis showed that tacrolimus had 43 target genes, and the GO enrichment results showed many potential functions. Further analysis found that there were 5 key target genes in DEGs, and these 5 genes were significantly down-regulated in liver transplant patients. Another important finding was that 5 genes were significantly related to some immune infiltrating cells. The results of the GSE84908 data analysis showed that after tacrolimus treatment, the expression of DAAM1 was significantly increased (p = 0.015).

Conclusion

Tacrolimus may inhibit the human immune response by affecting the expression of DAAM1 in liver transplant patients.

Berunda Polypeptides: Biheaded Rapamycin Carriers for Subcutaneous Treatment of Autoimmune Dry Eye Disease

The USFDA-approved immunosuppressive drug rapamycin (Rapa), despite its potency, is limited by poor bioavailability and a narrow therapeutic index. In this study, we sought to improve bioavailability of Rapa with subcutaneous (SC) administration and to test its therapeutic feasibility and practicality in a murine model of Sjögren's syndrome (SS), a systemic autoimmune disease with no approved therapies. To improve its therapeutic index, we formulated Rapa with a carrier termed FAF, a fusion of the human cytosolic FK506-binding protein 12 (FKBP12) and an elastin-like polypeptide (ELP). The resulting 97 kDa FAF (i) has minimal burst release, (ii) is "humanized", (iii) is biodegradable, (iv) solubilizes two Rapa per FAF, and (v) avoids organic solvents or amphiphilic carriers. Demonstrating high stability, FAF remained soluble and monodisperse with a hydrodynamic radius of 8 nm at physiological temperature. A complete pharmacokinetic (PK) analysis of FAF revealed that the bioavailability of SC FAF was 60%, with significantly higher blood concentration during the elimination phase compared to IV FAF. The plasma concentration of Rapa delivered by FAF was 8-fold higher with a significantly increased plasma-to-whole blood ratio relative to free Rapa, 24 h after injection. To evaluate therapeutic effects, FAF-Rapa was administered SC every other day for 2 weeks to male non-obese diabetic (NOD) mice, which develop an SS-like autoimmune-mediated lacrimal gland (LG) inflammation and other characteristic features of SS. Both FAF-Rapa and free Rapa exhibited immunomodulatory effects by significantly suppressing lymphocytic infiltration, gene expression of IFN-γ, MHC II, type I collagen and IL-12a, and cathepsin S (CTSS) activity in LG compared to controls. Serum chemistry and histopathological analyses in major organs revealed no apparent toxicity of FAF-Rapa. Given its improved PK and equipotent therapeutic efficacy compared to free Rapa, FAF-Rapa is of further interest for systemic treatments for autoimmune diseases like SS.

[Rapamycin alleviates inflammation by up-regulating TGF-β/Smad signaling in a mouse model of autoimmune encephalomyelitis]

OBJECTIVE

To evaluate the efficacy of rapmycin for treatment of experimental autoimmune encephalomyelitis (EAE) in mice and explore the underlying mechanism.

METHODS

An EAE model was established in C57BL/6 mice. After immunization, the mice were divided into model group and rapamycin groups treated daily with low-dose (0.3 mg/kg) or high-dose (1 mg/kg) rapamycin. The clinical scores of the mice were observed using Knoz score, the infiltration of IL-17 cells in the central nervous system (CNS) was determined using immunohistochemistry; the differentiation of peripheral Treg cells was analyzed using flow cytometry, and the changes in the levels of cytokines were detected with ELISA; the changes in the expressions of p-Smad2 and p- smad3 were investigated using Western blotting.

RESULTS

High-dose rapamycin significantly improved the neurological deficits scores of EAE mice. In high-dose rapamycin group, the scores in the onset stage, peak stage and remission stage were 0.14±0.38, 0.43±1.13 and 0.14±0.37, respectively, as compared with 1.14±0.69, 2.14±1.06 and 2.2±0.75 in the model group. The infiltration of inflammatory IL-17 cells was significantly lower in high-dose rapamycin group than in the model group (43±1.83 vs 153.5±7.02). High-dose rapamycin obviously inhibited the production of IL-12, IFN-γ, IL-17 and IL-23 and induced the anti-inflammatory cytokines IL-10 and TGF-β. The percentage of Treg in CD4+ T cells was significantly higher in high- dose rapamycin group than in the model group (10.17 ± 0.68 vs 3.52 ± 0.32). In the in vitro experiment, combined treatments of the lymphocytes isolated from the mice with rapamycin and TGF-β induced a significant increase in the number of Treg cells (13.66±1.89) compared with the treatment with rapamycin (6.23±0.80) or TGF-β (4.87±0.85) alone. Rapamycin also obviously up-regulated the expression of p-Smad2 and p-Smad3 in the lymphocytes.

CONCLUSIONS

Rapamycin can promote the differentiation of Treg cells by up-regulating the expression of p-Smad2 and p-smad3 to improve neurological deficits in mice with EAE.

Disease activity in progressive multiple sclerosis can be effectively reduced by cladribine

BACKGROUND

Evidence suggests people with non-relapsing deteriorating ("progressive") multiple sclerosis (pwPMS) may benefit from disease-modifying immune therapy (DMT). However, only one such treatment (ocrelizumab) has been licensed and is highly restricted to pwPMS suffering from the primary progressive phenotype. The difficulties assessing treatment outcome in pwPMS is one important reason for the lack of respective DMT. The concentration of neurofilaments in the cerebrospinal fluid (CSF) provides a biomarker of neuro-axonal damage, and both neurofilament light (NfL) and heavy chain (NfH) levels have been used as outcome indices and to guide treatment choices.

METHODS

We report on two pwPMS, who were treated with subcutaneous cladribine undergoing CSF NfL testing, alongside MRI and clinical follow-up, before and after treatment.

RESULTS

Cladribine treatment was well tolerated without any side effects. CSF NfL after treatment revealed significant reduction (by 73% and 80%, respectively) corroborating the MRI detectable drop in disease activity. Disability mildly progressed in one, and remained stable in the other pwPMS.

CONCLUSIONS

pwPMS with detectable disease activity (MRI, elevated NfL) should be considered for DMT. NfL appears to be a sensitive index of treatment effect in pwPMS, and may be a useful outcome in clinical trials targeting this patient group. Over and above its licensed indication (relapsing MS), cladribine may be an effective treatment option for pwPMS.

First-in-class inhibitor of the T cell receptor for the treatment of autoimmune diseases

Modulating T cell activation is critical for treating autoimmune diseases but requires avoiding concomitant opportunistic infections. Antigen binding to the T cell receptor (TCR) triggers the recruitment of the cytosolic adaptor protein Nck to a proline-rich sequence in the cytoplasmic tail of the TCR's CD3ε subunit. Through virtual screening and using combinatorial chemistry, we have generated an orally available, low-molecular weight inhibitor of the TCR-Nck interaction that selectively inhibits TCR-triggered T cell activation with an IC₅₀ (median inhibitory concentration) ~1 nM. By modulating TCR signaling, the inhibitor prevented the development of psoriasis and asthma and, furthermore, exerted a long-lasting therapeutic effect in a model of autoimmune encephalomyelitis. However, it did not prevent the generation of a protective memory response against a mouse pathogen, suggesting that the compound might not exert its effects through immunosuppression. These results suggest that inhibiting an immediate TCR signal has promise for treating a broad spectrum of human T cell-mediated autoimmune and inflammatory diseases.

Cladribine to treat disease exacerbation after fingolimod discontinuation in progressive multiple sclerosis

Rebound disease following cessation of disease modifying treatment (DMT) has been reported in people with both relapsing and progressive multiple sclerosis (pwRMS, pwPMS) questioning strict separation between these two phenotypes. While licensed DMT is available for pwRMS to counter rebound disease, no such option exists for pwPMS. We report on a pwPMS who developed rebound disease, with 45 Gadolinium-enhancing lesions on T1 weighted MRI brain, within 6 months after fingolimod 0.5 mg/day was stopped. Treatment with a short course of subcutaneous cladribine 60 mg led to effective suppression of inflammatory activity and partial recovery with no short-term safety issues or adverse events.

Disease-modifying therapies in multiple sclerosis in Latin America

The treatment of multiple sclerosis (MS) has become increasingly complex during the last 10 years, mainly because of the advent of new and more potent disease-modifying therapies (DMTs). In Latin America, the therapeutic repertoire available for MS treatment is similar to the one in the rest of the world, but the high costs of these drugs, in conjunction with the limited resources of the social security health systems, makes the treatment of MS more difficult. For neurologists in Latin America, providing personalized MS treatment has become a challenge. We present a review of the status of the DMT in Central and South America, benefits as well as limitations for providing full access to these medications in Latin America.

Occipital lobe gumma: a case report and review of the literature

Syphilis has plagued humanity for thousands of years. Despite the measures of precaution against its transmission and the advancement of modern pharmacology, late-stage phenomena like intracerebral gumma are not uncommon even today. We present a complex case, which has misled the physicians twice. Additionally, we performed a review of the contemporary literature about the common location, clinical findings and up-to-date treatment of intracerebral gummas.

Mycophenolate mofetil improves neurological function and alters blood T-lymphocyte subsets in rats with experimental autoimmune encephalomyelitis

Objective

This study evaluated the clinical and pathological effects of the immunosuppressive agent mycophenolate mofetil (MMF) in rats with experimental autoimmune encephalomyelitis (EAE; a model of multiple sclerosis [MS]).

Methods

EAE rats were randomly divided into 4 groups: model alone ( n = 7); low- or high-dose MMF (20 and 30 mg/kg per day, respectively, n = 6 each) orally for 14 days; methylprednisolone (20 mg/kg per day, n = 6) injected once daily for 3 days. Six normal Wistar rats served as controls. Clinical signs and histopathological findings were evaluated 14 days after treatment started.

Results

Oral administration of high-dose MMF significantly ameliorated the course of EAE in rats: cumulative clinical scores were lower and weight loss was less than in rats receiving methylprednisolone. The ameliorated disease course was associated with alleviation of histopathological signs of EAE. Treatment increased the blood proportion of CD8+, CD4+CD25+ and CD4+CD45RA+ T cells, with a concomitant reduced proportion of CD4+ T cells and ratio of CD4+ to CD8+ T cells, compared with EAE model alone rats.

Conclusions

MMF may have pharmacological potential in MS treatment and these findings may help in understanding the pathophysiological mechanism of MS.

A rapamycin-binding protein polymer nanoparticle shows potent therapeutic activity in suppressing autoimmune dacryoadenitis in a mouse model of Sjögren's syndrome

Sjögren's syndrome (SjS) is a chronic autoimmune disease characterized initially by lymphocytic infiltration and destruction of exocrine glands, followed by systemic organ damage and B-cell lymphoma. Conventional treatment is based on management of symptoms and there is a shortage of therapies that address the underlying causes of inflammation at source exocrine tissue. The aim of this study was to test a novel protein polymer-based platform consisting of diblock copolymers composed from Elastin-like Polypeptides (ELPs) fused with FKBP12, to deliver a potent immunosuppressant with dose-limiting toxicity, rapamycin (Rapa) also known as Sirolimus, and evaluate its effects on the inflamed lacrimal gland (LG) of non-obese diabetic mouse (NOD), a classic mouse model of SjS. Both soluble and diblock copolymer ELPs were fused to FKBP12 and characterized with respect to purity, hydrodynamic radii, drug entrapment and release. Both formulations showed successful association with Rapa; however, the nanoparticle formulation, FSI, released drug with nearly a 5 fold longer terminal half-life of 62.5h. The strong interaction of FSI nanoparticles with Rapa was confirmed in vivo by a shift in the monoexponential pharmacokinetic profile for free drug to a biexponential profile for the nanoparticle formulation. When acutely administered by injection into NOD mice via the tail vein, this FSI formulation significantly suppressed lymphocytic infiltration in the LG relative to the control group while reducing toxicity. There was also a significant effect on inflammatory and mammalian target of Rapamycin (mTOR) pathway genes in the LG and surprisingly, our nanoparticle formulation was significantly better at decreasing a proposed tear biomarker of SjS, cathepsin S (CATS) compared to free drug. These findings suggest that FSI is a promising tool for delivering Rapa for treatment of SjS in a murine model and may be further explored to meet the unmet medical challenge of SjS.

Role of immunosuppressive therapy for the treatment of multiple sclerosis

Immunosuppressives have been used in multiple sclerosis (MS) since 1966. Today, we have many treatments for the relapsing forms of the disease, including 8 US Food and Drug Administration-approved therapies, with more soon to be introduced. Given the current treatment landscape what place do immunosuppressants have in combating MS? Trial work and our experience suggest that immunosuppressives still have an important role in treating MS. Cyclophosphamide finds use in treating patients with severe, inflammatory relapsing remitting MS or those suffering from a fulminant attack. We tend to employ mycophenolate mofetil as an add-on to injectable therapy for patients experiencing breakthrough activity. Some progressive (primary progressive multiple sclerosis or secondary progressive multiple sclerosis) patients may stabilize after treatment with either cyclophosphamide or mycophenolate. We rarely employ mitoxantrone because of potential cardiac or carcinogenic effects. We prefer to use cyclophosphamide or mycophenolate mofetil in preference to methotrexate because evidence of efficacy is limited for this drug. We have less experience with azathioprine, but it may be an alternative for patients with limited options who are unable to tolerate conventional therapies.

Pharmacogenomic update on multiple sclerosis: a focus on actual and new therapeutic strategies

Multiple sclerosis (MS) is an inflammatory and demyelinating disease of central nervous system comprising several subtypes. Pharmacological treatment involves only few drugs. Among these, interferon beta (IFN-β) and glatiramer acetate were the most used. Although evidence supports the efficacy of these agents in treating MS symptoms, actual studies allowed to introduce new innovative drugs in clinical practice. Applying pharmacogenetic approach to MS, IFN-β and several other immune pathways were abundantly investigated. Numerous reports identified some promising therapy markers but only few markers have emerged as clinically useful. This may be partially due to differences in clinical and methodological criteria in the studies. Indeed, responder and non-responder definitions lack standardized clinical definition. The goal of this review is to treat advances in research on the pharmacogenetic markers of MS drugs and to highlight possible correlations between type of responses and genetic profile, with regard to clinical and methodological discrepancies in the studies.

A mechanistically novel, first oral therapy for multiple sclerosis: the development of fingolimod (FTY720, Gilenya)

Multiple sclerosis (MS) is a chronic autoimmune disorder affecting the central nervous system (CNS) through demyelination and neurodegeneration. Until recently, major therapeutic treatments have relied on agents requiring injection delivery. In September 2010, fingolimod/FTY720 (Gilenya, Novartis) was approved by the FDA as the first oral treatment for relapsing forms of MS. Fingolimod is a novel compound produced by chemical modification of a fungal precursor. Its active metabolite, formed by in vivo phosphorylation, modulates sphingosine 1-phosphate (S1P) receptors that are a subset of a larger family of cell-surface, G protein-coupled receptors (GPCRs) mediating the effects of bioactive lipids known as lysophospholipids. Fingolimod's mechanism of action in MS is not completely understood; however, its relevant biology indicates a fundamentally different mechanism compared to all previously approved MS therapies, with evolving research supporting both immunological and nervous system activities. This duality may herald a paradigm shift in the treatment of MS and other neurological disorders.

[Recurrent acute rhombencephalomyelitis in an adult or neuromyelitis optica? Presentation of a case]

INTRODUCTION

The lack of accepted homogeneous criteria for the definition of some demyelinating diseases makes diagnostic characterization difficult and limits data interpretation and therapeutic recommendations. Recurrent encephalomyelitis (ADE-R) along with borderline cases of neuromyelitis optica (NMO) are especially controversial.

OBJECTIVE

To describe the clinical and radiological evolution of an adult-onset ADE-R versus NMO case throughout 9 years of follow-up.

PATIENT AND METHODS

Our patient presented with severe symptoms of rhombencephalomyelitis and the cranial and spinal magnetic resonance imaging (MRI) showed large lesions, with gadolinium enhancement in brainstem and spinal cord, correlating with the clinical picture. Infectious aetiology was excluded, IgG index was normal and NMO antibodies were negative. After treatment with intravenous corticosteroids and plasmapheresis, there was excellent recovery in the acute phase. During follow-up, seven relapses have occurred, mainly in the spinal cord, with good recovery and the same symptomatology, albeit with different severity. Immunosuppressive treatment was introduced since the beginning.

CONCLUSIONS

Our case shares common features of both ADE-R and NMO, illustrating that diagnostic characterization is not easy in spite of current criteria.

Successful management of a neurology infusion practice

The increasing use of infusible biologic therapies, including the novel monoclonal antibody natalizumab for the treatment of relapsing forms of multiple sclerosis, has elicited much interest among neurologists in the provision of in-office infusions for their patients. An in-office infusion center may offer neurologists a means to provide integrated care for their patients in a familiar and supportive environment. This setting is especially convenient for chronically ill patients, allowing them to receive high-quality care under the direct supervision of their neurologist and facility staff. By administering infusible treatments in a neurology practice rather than referring patients to a hospital or oncology/hematology-based infusion center, the primary neurologist can more closely monitor clinical outcomes, treatment adherence, and the occurrence of adverse effects. In addition, there is greater opportunity for patient interaction and education, which can strengthen relationships with clinical caregivers. This model is also applicable to multispecialty or hospital-based neurology groups desiring to integrate neurology infusion services. In this article, we discuss overall management strategies; staffing and scheduling issues; general coding, billing, and reimbursement methodologies; and additional financial considerations.

Animal models of multiple sclerosis--potentials and limitations

Experimental autoimmune encephalomyelitis (EAE) is still the most widely accepted animal model of multiple sclerosis (MS). Different types of EAE have been developed in order to investigate pathogenetic, clinical and therapeutic aspects of the heterogenic human disease. Generally, investigations in EAE are more suitable for the analysis of immunogenetic elements (major histocompatibility complex restriction and candidate risk genes) and for the study of histopathological features (inflammation, demyelination and degeneration) of the disease than for screening of new treatments. Recent studies in new EAE models, especially in transgenic ones, have in connection with new analytical techniques such as microarray assays provided a deeper insight into the pathogenic cellular and molecular mechanisms of EAE and potentially of MS. For example, it was possible to better delineate the role of soluble pro-inflammatory (tumor necrosis factor-α, interferon-γ and interleukins 1, 12 and 23), anti-inflammatory (transforming growth factor-β and interleukins 4, 10, 27 and 35) and neurotrophic factors (ciliary neurotrophic factor and brain-derived neurotrophic factor). Also, the regulatory and effector functions of distinct immune cell subpopulations such as CD4+ Th1, Th2, Th3 and Th17 cells, CD4+FoxP3+ Treg cells, CD8+ Tc1 and Tc2, B cells and γδ+ T cells have been disclosed in more detail. The new insights may help to identify novel targets for the treatment of MS. However, translation of the experimental results into the clinical practice requires prudence and great caution.

Management of multiple sclerosis in adolescents - current treatment options and related adherence issues

Multiple sclerosis (MS) is a progressive inflammatory demyelinating disorder of the central nervous system that is increasingly recognized in children and adolescents. This realization comes with additional concerns about existing therapeutic options and the impact of the disease on health-related outcomes of adolescents with MS. This five-part review provides an update on management strategies relevant to the pediatric MS population. The first section gives an overview on the epidemiology and natural history of early onset MS. The second section outlines currently available MS treatments, including medications during acute relapses and long-term immunomodulatory therapies. The third section highlights adherence issues pertaining to MS, including the challenges uniquely faced by adolescents. The fourth section provides a summary of research into quality of life and psychosocial consequences of pediatric onset MS. Attention is drawn to the grief experience of affected adolescents and the importance of peer relationships. Finally, the family resilience framework is presented as a conceptual model to facilitate optimal adaptation of adolescents with MS. Healthcare professionals can promote resilience and treatment adherence by ensuring that these individuals and their families are sufficiently informed about available MS treatments, providing instrumental support for managing potential medication side effects, and addressing age-appropriate developmental needs.

Rapamycin inhibits relapsing experimental autoimmune encephalomyelitis by both effector and regulatory T cells modulation

Rapamycin is an oral immunosuppressant drug previously reported to efficiently induce naturally occurring CD4(+)CD25(+)FoxP3(+) regulatory T ((n)T(reg)) cells re-establishing long-term immune self-tolerance in autoimmune diseases. We investigated the effect of rapamycin administration to SJL/j mice affected by PLP(139-151)-induced relapsing-remitting experimental autoimmune encephalomyelitis (RR-EAE). We found that oral or intraperitoneal treatment at the peak of disease or at the end of the first clinical attack, dramatically ameliorated the clinical course of RR-EAE. Treatment suspension resulted in early reappearance of disease. Clinical response was associated with reduced central nervous system demyelination and axonal loss. Rapamycin induced suppression of IFN-gamma, and IL-17 release from antigen-specific T cells in peripheral lymphoid organs. While CD4(+)FoxP3(+) cells were unaffected, we observed disappearance of CD4(+)CD45RB(high) effector T (T(eff)) cells and selective expansion of T(reg) cells bearing the CD4(+)CD45RB(low)FoxP3(+)CD25(+)CD103(+) extended phenotype. Finally, the dual action of rapamycin on both T(eff) and T(reg) cells resulted in modulation of their ratio that closely paralleled disease course. Our data show that rapamycin inhibits RR-EAE, provide evidence for the immunological mechanisms, and indicate this compound as a potential candidate for the treatment of multiple sclerosis.

Neurodegenerative disorders and nanoformulated drug development

Degenerative and inflammatory diseases of the CNS include, but are not limited to, Alzheimer's and Parkinson's disease, amyotrophic lateral sclerosis, stroke, multiple sclerosis and HIV-1-associated neurocognitive disorders. These are common, debilitating and, unfortunately, hold few therapeutic options. In recent years, the application of nanotechnologies as commonly used or developing medicines has served to improve pharmacokinetics and drug delivery specifically to CNS-diseased areas. In addition, nanomedical advances are leading to therapies that target CNS pathobiology and as such, can interrupt disordered protein aggregation, deliver functional neuroprotective proteins and alter the oxidant state of affected neural tissues. This article focuses on the pathobiology of common neurodegenerative disorders with a view towards how nanomedicine may be used to improve the clinical course of neurodegenerative disorders.

B-type natriuretic peptide as a marker of subclinical heart injury during mitoxantrone therapy in MS patients--preliminary study

The aim of this study was to evaluate the plasma level changes of B-type natriuretic peptide (BNP), biochemical marker of heart failure, and echocardiographic parameters during mitoxantrone treatment in 22 multiple sclerosis (MS) patients (8 males, 14 females, mean age 37.1+/-6.6). Mitoxantrone (after mean cumulative dose of 58.0+/-7.0 mg/m(2)) did not alter left ventricular ejection fraction (LVEF), left ventricular end-diastolic diameter (LVEDD), posterior wall thickness (PWT) and left ventricular end-diastolic volume (LVEDV). However, mean plasma level of BNP raised from 14.53+/-3.29 pg/ml at the baseline to 16.79+/-3.05 pg/ml and 18.83+/-4.90 pg/ml (P<0.01) after mean mitoxantrone dose of 30.7+/-5.9 mg/m(2) and 58.0+/-7.0 mg/m(2), respectively. These results strongly suggest subclinical myocardial dysfunction in mitoxantrone-treated group. We assume, that low-cost, repeated BNP measurements may be a good alternative for detection of early subtle myocardial injury in MS patients during routine mitoxantrone therapy.

Mapping similarities in mTOR pathway perturbations in mouse lupus nephritis models and human lupus nephritis

Introduction

Treatment with sirolimus, a mammalian target of rapamycin (mTOR) inhibitor, has been shown to be efficacious in the MRL/lpr and NZB × NZW F1 mouse models of lupus nephritis, indicating a critical role for the mTOR pathway in both models. This type of demonstration of efficacy in animal models is usually a pre-requisite for advancement into clinical development. However, efficacy in an animal model often has not translated to the desired activity in the clinic. Therefore, a more profound understanding of the mechanistic similarities and differences between various animal models and human diseases is highly desirable.

Methods

Transcriptional profiling was performed on kidneys from mice with lupus nephritis; from mice who had efficacious drug treatment; and from mice before they developed nephritis. Analysis of variance with false discovery rate adjusted to p < 0.05 and an average fold change of two or more was used to identify transcripts significantly associated with disease and response to therapy. Pathway analyses (using various bioinformatics tools) were carried out to understand the basis for drug efficacy in the mouse model. The relevance in human lupus of the pathways identified in the mouse model was explored using information from several databases derived from the published literature.

Results

We identified a set of nephritis-associated genes in mouse kidney. Expression of the majority of these returned to asymptomatic levels on sirolimus treatment, confirming the correlation between expression levels and symptoms of nephritis. Network analysis showed that many of these nephritis genes are known to interact with the mTOR pathway. This led us to ask what human diseases are linked to the mTOR pathway. We constructed the mTOR pathway interactome consisting of proteins that interact with members of the mTOR pathway and identified a strong association between mTOR pathway genes and genes reported in the literature as being involved in human lupus.

Conclusions

Our findings implicate the mTOR pathway as a critical contributor to human lupus. This broad pathway-based approach to understanding the similarities in, and differences between, animal models and human diseases may have broader utility.