Dimethyl fumarate, a small molecule drug for psoriasis, inhibits Nuclear Factor-kappaB and reduces myocardial infarct size in rats

Neuroprotective effects of dimethyl fumarate against manic-like behavior induced by ketamine in rats

Medications for treating bipolar disorder (BD) are limited and can cause side effects if used chronically. Therefore, efforts are being made to use new agents in the control and treatment of BD. Considering the antioxidant and anti-inflammatory effects of dimethyl fumarate (DMF), this study was performed to examine the role of DMF on ketamine (KET)-induced manic-like behavior (MLB) in rats. Forty-eight rats were randomly divided into eight groups, including three groups of healthy rats: normal, lithium chloride (LiCl) (45 mg/kg, p.o.), and DMF (60 mg/kg, p.o.), and five groups of MLB rats: control, LiCl, and DMF (15, 30, and 60 mg/kg, p.o.), which received KET at a dose of 25 mg/kg, i.p. The levels of total sulfhydryl groups (total SH), thiobarbituric acid reactive substances (TBARS), nitric oxide (NO), and tumor necrosis factor-alpha (TNF-α), as well as the activity of antioxidant enzymes including catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) in the prefrontal cortex (PFC) and hippocampus (HPC), were measured. DMF prevented hyperlocomotion (HLM) induced by KET. It was found that DMF could inhibit the increase in the levels of TBARS, NO, and TNF-α in the HPC and PFC of the brain. Furthermore, by examining the amount of total SH and the activity of SOD, GPx, and CAT, it was found that DMF could prevent the reduction of the level of each of them in the brain HPC and PFC. DMF pretreatment improved the symptoms of the KET model of mania by reducing HLM, oxidative stress, and modulating inflammation.

Novel potential pharmacological applications of dimethyl fumarate-an overview and update

Dimethyl fumarate (DMF) is an FDA-approved drug for the treatment of psoriasis and multiple sclerosis. DMF is known to stabilize the transcription factor Nrf2, which in turn induces the expression of antioxidant response element genes. It has also been shown that DMF influences autophagy and participates in the transcriptional control of inflammatory factors by inhibiting NF-κB and its downstream targets. DMF is receiving increasing attention for its potential to be repurposed for several diseases. This versatile molecule is indeed able to exert beneficial effects on different medical conditions through a pleiotropic mechanism, in virtue of its antioxidant, immunomodulatory, neuroprotective, anti-inflammatory, and anti-proliferative effects. A growing number of preclinical and clinical studies show that DMF may have important therapeutic implications for chronic diseases, such as cardiovascular and respiratory pathologies, cancer, eye disorders, neurodegenerative conditions, and systemic or organ specific inflammatory and immune-mediated diseases. This comprehensive review summarizes and highlights the plethora of DMF's beneficial effects and underlines its repurposing opportunities in a variety of clinical conditions.

Dimethyl fumarate protects against intestine damage in necrotizing enterocolitis by inhibiting the Toll-like receptor (TLR) inflammatory signaling pathway

OBJECTIVE

Necrotizing enterocolitis (NEC) is a severe disease in newborns, this study aimed to investigate the protective effect of dimethyl fumarate (DMF) on NEC and its possible mechanism.

METHODS

In vivo, the mice were divided into the control, NEC, and NEC+DMF group. The NEC model was established by artificial feeding, hypoxic for 4 days, and lipopolysaccharide (LPS) stimulation on day 2 and day 3. DMF (25 mg/kg/d) was administered to NEC mice on day 1 and day 3. On the 11th day, the blood and intestinal tissues of mice were taken for enzyme-linked immunosorbent assay (ELISA), pathological examination, quantitative real-time PCR (RT-qPCR), Western blot, and immunohistochemical (IHC) detection. In vitro, human colorectal cells (FHC) were induced by LPS (100 ng/mL) and was divided into the control, LPS, and LPS+DMF group. The effect of DMF (20 μM) on cell viability and TLR4 signal transduction was detected by MTT and RT-qPCR, respectively.

RESULTS

Compared to the NEC mice, DMF attenuated NEC-induced weight loss and abdominal distension diarrhea in mice, and alleviated NEC-induced intestinal pathological injuries. In addition, DMF reduced the expression of IL-6, IL-1β, TNF-α, NF-κB, and TLR4 in NEC mice intestinal tissues. Furthermore, DMF inhibited NEC-induced intestinal cell apoptosis as well as the protein expression of BCL2-Associated X (BAX), caspase-3, caspase-9, and increased Bcl-2 (B-cell lymphoma-2) expression. In vitro, DMF improved cell viability, and restrained NF-κB and TLR4 expression in LPS-induced NEC cells.

CONCLUSION

DMF has a protective effect against intestine damage of NEC, which is related to the inhibition of the TLR signaling pathway, alleviating the inflammatory response.

Dimethyl Fumarate Ameliorates Doxorubicin-Induced Cardiotoxicity By Activating the Nrf2 Pathway

Doxorubicin (DOX) is limited in clinical application because of its cardiotoxicity. Oxidative stress and apoptosis are crucial in DOX-induced cardiac injury. Dimethyl fumarate (DMF) is an FDA-approved oral drug with powerful effects to reduce oxidative stress and apoptosis through the Nrf2 pathway. This study was aimed to determine whether DMF can protect against DOX-induced cardiac injury. We used both neonatal rat cardiomyocytes (NRCMs) in vitro and DOX-induced cardiac toxicity in vivo to explore the effects of DMF. The results showed that DMF significantly improved cell viability and morphology in NRCMs. In addition, DMF alleviated DOX-induced cardiac injury in rats, as evidenced by decreased CK-MB, LDH levels, improved survival rates, cardiac function, and pathological changes. Moreover, DMF significantly inhibited cardiac oxidative stress by reducing MDA levels and increasing GSH, SOD, and GSH-px levels. And DMF also inhibited DOX-induced cardiac apoptosis by modulating Bax, Bcl-2 and cleaved caspase-3 expression. Moreover, DMF exerted its protective effects against DOX by promoting Nrf2 nuclear translocation, which activated its downstream antioxidant gene Hmox1. Silencing of Nrf2 attenuated the protective effects of DMF in NRCMs as manifested by increased intracellular oxidative stress, elevated apoptosis levels, and decreased cell viability. In addition, DMF showed no protective effects on the viability of DOX-treated tumor cells, which suggested that DMF does not interfere with the antitumor effect of DOX in vitro. In conclusion, our data confirmed that DMF alleviated DOX-induced cardiotoxicity by regulating oxidative stress and apoptosis through the Nrf2 pathway. DMF may serve as a new candidate to alleviate DOX-related cardiotoxicity in the future.

Repurposing Dimethyl Fumarate for Cardiovascular Diseases: Pharmacological Effects, Molecular Mechanisms, and Therapeutic Promise

Dimethyl fumarate (DMF) is a small molecule that has been shown to assert potent in vivo immunoregulatory and anti-inflammatory therapeutic actions. The drug has been approved and is currently in use for treating multiple sclerosis and psoriasis in the USA and Europe. Since inflammatory reactions have been significantly implicated in the etiology and progression of diverse disease states, the pharmacological actions of DMF are presently being explored and generalized to other diseases where inflammation needs to be suppressed and immunoregulation is desirable, either as a monotherapeutic agent or as an adjuvant. In this review, we focus on DMF, and present an overview of its mechanism of action while briefly discussing its pharmacokinetic profile. We further discuss in detail its pharmacological uses and highlight its potential applications in the treatment of cardiovascular diseases. DMF, with its unique combination of anti-inflammatory and vasculoprotective effects, has the potential to be repurposed as a therapeutic agent in patients with atherosclerotic cardiovascular disease. The clinical studies mentioned in this review with respect to the beneficial effects of DMF in atherosclerosis involve observations in patients with multiple sclerosis and psoriasis in small cohorts and for short durations. The findings of these studies need to be assessed in larger prospective clinical trials, ideally with a double-blind randomized study design, investigating the effects on cardiovascular endpoints as well as morbidity and mortality. The long-term impact of DMF therapy on cardiovascular diseases also needs to be confirmed.

Dimethyl fumarate protects the aged brain following chronic cerebral hypoperfusion-related ischemia in rats in Nrf2-dependent manner

It has been stated that chronic cerebral hypoperfusion (CCH) markedly prompts neuronal damage and affects cognition. Dimethyl fumarate (DMF), a nuclear erythroid 2-related factor 2 (Nrf2) activator, represents a class of molecules exhibiting neuroprotection. We explored the effect of DMF on CCH using a model of permanent left common carotid occlusion. The left common carotid artery was occluded and then DMF (100mg.kg^-1) was orally administrated three times per week for four consecutive weeks. Behavioral rests, PET imaging and Hematoxylin and Eosin staining, were examined and also, the hippocampal level of inflammatory, Nrf2 antioxidant, neuronal plasticity and apoptotic factors were determined using Western blot analysis and related ELISA kits. The neurological deficit scores were significantly reduced in the treatment group compared with the CCH group (P<0.001). DMF decreased the novel object recognition index (NOR) compared with the CCH group, while CCH + DMF increased the NOR compared with the CCH group (P<0.001). CCH + DMF reduces the ratio of Bax/Bcl2 and capase-3 activity in comparison to the CCH group (P<0.001). Treatment with DMF increased Nrf2, NAD(P)H dehydrogenase-1 and Heme oxygenase-1 and decreased Tumor necrosis factor α and Nuclear factor-κB density compared with the CCH group (P<0.001). A significant increase in brain-derived neurotrophic factor and c-fos was found in DMF-treated rats compared with the CCH group (P<0.001). Also, retinoic acid inhibits Nrf2 activation via DMF and increases inflammatory factors in hypoperfused rats' hippocampus compared with the CCH group (P<0.001). Long-term DMF treatment induces the Nrf2 pathway and has beneficial effects on memory and motility in CCH.

Dimethyl fumarate preserves left ventricular infarct integrity following myocardial infarction via modulation of cardiac macrophage and fibroblast oxidative metabolism

Myocardial infarction (MI) is one of the leading causes of mortality and cardiovascular disease worldwide. MI is characterized by a substantial inflammatory response in the infarcted left ventricle (LV), followed by transition of quiescent fibroblasts to active myofibroblasts, which deposit collagen to form the reparative scar. Metabolic shifting between glycolysis and mitochondrial oxidative phosphorylation (OXPHOS) is an important mechanism by which these cell types transition towards reparative phenotypes. Thus, we hypothesized that dimethyl fumarate (DMF), a clinically approved anti-inflammatory agent with metabolic actions, would improve post-MI remodeling via modulation of macrophage and fibroblast metabolism. Adult male C57BL/6J mice were treated with DMF (10 mg/kg) for 3-7 days after MI. DMF attenuated LV infarct and non-infarct wall thinning at 3 and 7 days post-MI, and decreased LV dilation and pulmonary congestion at day 7. DMF improved LV infarct collagen deposition, myofibroblast activation, and angiogenesis at day 7. DMF also decreased pro-inflammatory cytokine expression (Tnf) 3 days after MI, and decreased inflammatory markers in macrophages isolated from the infarcted heart (Hif1a, Il1b). In fibroblasts extracted from the infarcted heart at day 3, RNA-Seq analysis demonstrated that DMF promoted an anti-inflammatory/pro-reparative phenotype. By Seahorse analysis, DMF did not affect glycolysis in either macrophages or fibroblasts at day 3, but enhanced macrophage OXPHOS while impairing fibroblast OXPHOS. Our results indicate that DMF differentially affects macrophage and fibroblast metabolism, and promotes anti-inflammatory/pro-reparative actions. In conclusion, targeting cellular metabolism in the infarcted heart may be a promising therapeutic strategy.

Emerging Therapeutic Applications for Fumarates

Fumarates are successfully used for the treatment of psoriasis and multiple sclerosis. Their antioxidative, immunomodulatory, and neuroprotective properties make fumarates attractive therapeutic candidates for other pathologies. The exact working mechanisms of fumarates are, however, not fully understood. Further elucidation of the mechanisms is required if these drugs are to be successfully repurposed for other diseases. Towards this, administration route, dosage, and treatment timing, frequency, and duration are important parameters to consider and optimize with clinical paradigms in mind. Here, we summarize the rapidly expanding literature on the pharmacokinetics and pharmacodynamics of fumarates, including a discussion on two recently FDA-approved fumarates VumerityTM and BafiertamTM. We review emerging applications of fumarates, focusing on neurological and cardiovascular diseases.

NRF2 function in osteocytes is required for bone homeostasis and drives osteocytic gene expression

Osteocytes, the most abundant bone cell type, are derived from osteoblasts through a process in which they are embedded in an osteoid. We previously showed that nutrient restriction promotes the osteocyte transcriptional program and is associated with increased mitochondrial biogenesis. Here, we show that increased mitochondrial biogenesis increase reactive oxygen species (ROS) levels and consequently, NRF2 activity during osteocytogenesis. NRF2 activity promotes osteocyte-specific expression of Dmp1, Mepe, and Sost in IDG-SW3 cells, primary osteocytes, and osteoblasts, and in murine models with Nfe2l2 deficiency in osteocytes or osteoblasts. Moreover, ablation of Nfe2l2 in osteocytes or osteoblasts generates osteopenia and increases osteoclast numbers with marked sexual dimorphism. Finally, treatment with dimethyl fumarate prevented the deleterious effects of ovariectomy in trabecular bone masses of mice and restored osteocytic gene expression. Altogether, we uncovered the role of NRF2 activity in osteocytes during the regulation of osteocyte gene expression and maintenance of bone homeostasis.

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ROS levels and NRF2 activity are increased during osteocytogenesis.

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NRF2 drives osteocyte specification and activate the transcription of osteocyte-specific genes.

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NRF2 in osteocytes has a fundamental role in bone homeostasis and its deletion induces osteopenia.

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Activation of NRF2 with dimethyl fumarate prevents osteopenia induced by ovariectomy.

Oxidative Stress and Antioxidant Treatments in Cardiovascular Diseases

Oxidative stress plays a key role in many physiological and pathological conditions. The intracellular oxidative homeostasis is tightly regulated by the reactive oxygen species production and the intracellular defense mechanisms. Increased oxidative stress could alter lipid, DNA, and protein, resulting in cellular inflammation and programmed cell death. Evidences show that oxidative stress plays an important role in the progression of various cardiovascular diseases, such as atherosclerosis, heart failure, cardiac arrhythmia, and ischemia-reperfusion injury. There are a number of therapeutic options to treat oxidative stress-associated cardiovascular diseases. Well known antioxidants, such as nutritional supplements, as well as more novel antioxidants have been studied. In addition, novel therapeutic strategies using miRNA and nanomedicine are also being developed to treat various cardiovascular diseases. In this article, we provide a detailed description of oxidative stress. Then, we will introduce the relationship between oxidative stress and several cardiovascular diseases. Finally, we will focus on the clinical implications of oxidative stress in cardiovascular diseases.

Dimethyl fumarate protects cardiomyocytes against oxygen-glucose deprivation/reperfusion (OGD/R)-induced inflammatory response and damages via inhibition of Egr-1

Acute myocardial infarction (AMI) is associated with high rates of morbidity and mortality. Atherosclerosis is among the leading causes of AMI. The rupture or erosion of atherosclerotic plaques can obstruct coronary arteries, thereby leading to an acute inflammatory reaction to ischemic injury and cardiomyocyte apoptosis. Dimethyl fumarate (DMF) is a fumaric acid diester which is used for the treatment of psoriasis and multiple sclerosis. DMF is most well-known for its modulatory actions on the Nrf2 and NF-κB cellular signaling pathways. In the present study, we employed an oxygen-glucose deprivation/reoxygenation (OGD/R) model of myocardial ischemia/reperfusion injury using H9c2 cardiomyocytes to assess the potential protective effects of DMF. We found that DMF significantly improved cell viability and reduced the expression of pro-inflammatory cytokines and chemokines, including IL-6, IL-8, and MCP-1. We further demonstrated an antioxidant effect of DMF via reduced production of ROS, which was mediated through NOX4 inhibition. Tissue factor and ICAM-1 play a major role in left ventricular remodeling. DMF inhibited the expression of TF and ICAM-1 induced by OGD/R, which we demonstrated to be mediated through the Egr-1 signaling pathway, as silencing of Egr-1 suppressed the expression of TF and ICAM-1. Together, these findings demonstrate a potential role for DMF in the treatment of myocardial infarction.

Hemin reduces postoperative ileus in a heme oxygenase 1-dependent manner while dimethyl fumarate does without heme oxygenase 1-induction

BACKGROUND

Postoperative ileus (POI), the impairment of gastrointestinal motility after abdominal surgery, is mainly due to intestinal muscular inflammation. Carbon monoxide (CO)-releasing compounds were shown to exert an anti-inflammatory effect in murine POI partially through induction of heme oxygenase-1 (HO-1). The influence of hemin and dimethyl fumarate (DMF), currently used for multiple sclerosis (MS), was therefore tested in murine POI.

METHODS

C57BL/6J mice were anesthetized and after laparotomy, POI was induced via intestinal manipulation (IM). Animals were treated with either 30 mg kg^-1 hemin intraperitoneally (ip), 30 mg kg^-1 DMF ip, or 100 mg kg^-1 intragastrically (ig) 24 hours before IM. Intestinal transit was assessed 24 hours postoperatively and mucosa-free muscularis or whole segments of the small intestine were stored for later analysis. Intestinal HO-1 protein expression was studied at 6, 12, and 24 hours after administration of hemin or DMF in non-manipulated mice.

KEY RESULTS

Pretreatment with hemin and DMF, both ig and ip, prevented the delayed transit seen after IM. Concomitantly, both hemin and DMF significantly reduced the increased interleukin-6 levels and the elevated leukocyte infiltration in the muscularis. Hemin but not DMF caused a significant increase in intestinal HO-1 protein expression and co-administration of the HO-1 inhibitor chromium mesoporphyrin abolished the protective effects of hemin on POI; DMF reduced the IM-induced activation of NF-κB and ERK 1/2.

CONCLUSIONS AND INFERENCES

Both hemin and DMF improve the delayed transit and inflammation seen in murine POI, but only hemin does so in a HO-1-dependent manner.

Chronic inflammatory diseases, myocardial function and cardioprotection

The association between chronic inflammatory diseases (CIDs) and increased cardiovascular (CV) risk is well documented and can be a most threatening complication in these patients. However, the pathogenetic mechanisms underlying increased CV risk remain elusive, especially in their cellular and biochemical pathways. Using animal models to understand mechanisms underlying cardiac involvement are limited. Additionally, treatments may influence cardiovascular events through different outcomes. Some drugs used to treat CIDs can negatively affect cardiac function by a direct toxicity, whereas others may protect the myocardium. In the present article, we focus on the cardiac manifestations and risk factors, the pathogenetic mechanisms, and the effect of treatments on myocardial function and cardioprotection for five common worldwide CIDs (rheumatoid arthritis, systemic lupus erythematosus, systemic sclerosis, psoriasis and inflammatory bowel disease). We also give recommendations in order to evaluate common targets between CID and CV disease (CVD) and to design therapies to alleviate CID-related CVD. LINKED ARTICLES: This article is part of a themed issue on Risk factors, comorbidities, and comedications in cardioprotection. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v177.23/issuetoc.

Metabolomic Profile of Posner-Schlossman Syndrome: A Gas Chromatography Time-of-Flight Mass Spectrometry-Based Approach Using Aqueous Humor

The Posner-Schlossman syndrome (PSS) is a disease with clinically recurrent unilateral anterior uveitis with markedly elevated intraocular pressure (IOP) and subsequent progression to optic neuropathy. Retrospective studies have reported increased annual incidence of PSS, especially in China. While currently, the clinical management of PSS is still challenging. Metabolomics is considered to be a sensitive approach for the development of novel targeted therapeutics because of its direct elucidation of pathophysiological mechanisms. Therefore, we adopted gas chromatography time-of-flight mass spectrometry (GC-TOF-MS) technology-based non-targeted metabolomics approach to measure comprehensive metabolic profiles of aqueous humor (AH) samples obtained from patients with PSS, with an aim to demonstrate the underlying pathophysiology, identify potential biomarkers specific to PSS, and develop effective treatment strategies. A comparative analysis was used to indicate the distinct metabolites of PSS. Pathway analysis was conducted using MetaboAnalyst 4.0 to explore the metabolic reprogramming pathways involved in PSS. Logistic regression and receiver-operating characteristic (ROC) analyses were employed to evaluate the diagnostic capability of selected metabolites. Comparative analysis revealed a clear separation between PSS and control groups. Fourteen novel differentiating metabolites from AH samples obtained from patients with PSS were highlighted. Pathway analysis identified 11 carbohydrate, amino acid metabolism and energy metabolism pathways as the major disturbed pathways associated with PSS. The abnormal lysine degradation metabolism, valine-leucine-isoleucine biosynthesis, and citrate circle were considered to weigh the most in the development of PSS. The ROC analysis implied that the combination of glycine and homogentisic acid could serve as potential biomarkers for the discrimination of control and PSS groups. In conclusion, these results revealed for the first time the identity of important metabolites and pathways contributing to the development/progression of PSS, enabled the better understanding of the mechanism of PSS, and might lead to the development of metabolic biomarkers and novel therapeutic strategies to restrict the development/progression of PSS.

Reducing Pancreatic Fibrosis Using Antioxidant Therapy Targeting Nrf2 Antioxidant Pathway: A Possible Treatment for Chronic Pancreatitis

Chronic pancreatitis is the progressive inflammation of the pancreas resulting in the irreversible damage of pancreatic structure and function by means of fibrosis. Chronic pancreatitis is most commonly caused by alcohol consumption, although the direct molecular etiology is unknown. Recent studies suggest oxidative stress as a catalyst for pancreatic stellate cell activation leading to the deposition of collagenous extracellular matrix causing pancreatic fibrosis. We review the effect of oxidative stress on pancreatic fibrogenesis and indicate the molecular pathways involved in preventing oxidant-related cell damage. Likewise, we summarize existing antioxidative therapies for chronic pancreatitis and discuss a novel nuclear factor erythroid 2-related factor 2 activator, dimethyl fumarate, and its potential to reduce fibrogenesis by downregulating pancreatic stellate cell activation.

Dimethyl fumarate attenuates lipopolysaccharide-induced mitochondrial injury by activating Nrf2 pathway in cardiomyocytes

AIMS

To determine whether dimethyl fumarate (DMF) can protect against lipopolysaccharide (LPS) -induced myocardial injury.

MAIN METHODS

H9c2 cells pretreated with or without DMF were stimulated with LPS. Cell viability and apoptosis were evaluated. Nrf2 and HO-1 expression were detected using Western blotting. Mitochondrial morphology, mitochondrial superoxide production were observed using confocal microscope. Mitochondrial respiration function was measured using Seahorse bioanalyzer.

KEY FINDINGS

(1) The cell viability decreased, LDH release and apoptosis increased in LPS- challenged H9c2 cells. DMF pretreatment brought a higher cell viability, and a lower LDH leakage and apoptosis than those of LPS group (P < 0.01). (2) DMF pretreatment resulted in an increased Nrf2 and HO-1 expression, and enhanced nuclear Nrf2 level in LPS-challenged cells (P < 0.01). (3) Nrf2-siRNA could inhibit DMF-induced enhancement of HO-1 expression and cell viability, and partly abolish DMF-induced reduction of LDH leakage and apoptosis. (4) ERK1/2 inhibitor PD98059 could not only prevent the DMF-induced enhancement of nuclear Nrf2 and HO-1, but also inhibit DMF-induced increase in cell viability. (5) Compared with LPS-challenged cells, DMF pretreatment caused a lower production of mitochondrial superoxide and a higher mitochondrial membrane potential, which could be abolished by Nrf2-siRNA. (6) DMF could attenuate LPS-induced mitochondrial fragmentation and improve mitochondrial respiration function by enhancement of the oxygen consumption rate of basal respiration and ATP production in LPS-challenged cells (P < 0.01).

SIGNIFICANCE

DMF protects cardiomyocytes against LPS-induced damage. ERK1/2-dependent activation of Nrf2/HO-1 pathway is responsible for DMF-induced cardioprotection via reduction of oxidative stress, improvement of mitochondrial morphology and energy metabolism.

Dimethyl fumarate interferes with MyD88-dependent toll-like receptor signalling pathway in isoproterenol-induced cardiac hypertrophy model

Objectives

To investigate the effect of dimethyl fumarate (DMF) on Toll-like receptor (TLR) signalling pathway in isoproterenol (ISO)-induced cardiac hypertrophy in rats.

Methods

Sixty adult male Sprague-Dawley rats were randomly allocated into three groups. group I: rats received the vehicles only; group II: rats were treated with ISO (5 mg/kg per day S.C.) to induce cardiac hypertrophy for 7 days; and group III: rats were given DMF (25 mg/kg per 12 h P.O.) for 28 days, and at the last 7 days, they were treated with ISO (5 mg/kg per day S.C.).

Key findings

Pretreatment with DMF decreased heart-to-body weight ratio, heart rate and blood pressure and improved the electrocardiographic patterns when compared with ISO group. DMF exhibited cardioprotective effect as evidenced by the reduction in cardiac troponin I, creatine kinase-MB and atrial natriuretic peptide levels. Moreover, DMF alleviated the changed oxidative stress and inflammatory biochemical markers through its anti-inflammatory and antioxidant effects. DMF interfered with TLR signalling pathway, evidenced by decreased levels of the TLR adaptor protein MyD88 and p-ERK1/2 and increased p-Akt level.

Conclusions

Dimethyl fumarate exerted cardioprotective effect against ISO-induced cardiac hypertrophy. This effect is suggested to be through interfering with TLR signalling pathway.

The Neuroprotective Effect of Dimethyl Fumarate in an MPTP-Mouse Model of Parkinson's Disease: Involvement of Reactive Oxygen Species/Nuclear Factor-κB/Nuclear Transcription Factor Related to NF-E2

AIM

Oxidative stress plays a key role in Parkinson disease (PD), and nuclear transcription factor related to NF-E2 (Nrf-2) is involved in neuroprotection against PD. The aim of the present study was to investigate a role for nuclear factor-κB (NF-κB)/Nrf-2 in the neurotherapeutic action of dimethyl fumarate (DMF) in a mouse model of PD and in vitro in SHSY-5Y cells.

RESULTS

Daily oral gavage of DMF (10, 30, and 100 mg/kg) significantly reduced neuronal cell degeneration of the dopaminergic tract and behavioral impairments induced by four injections of the dopaminergic neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine. Moreover, treatment with DMF prevented dopamine depletion, increased tyrosine hydroxylase and dopamine transporter activities, and also reduced the number of α-synuclein-positive neurons. Furthermore, DMF treatment upregulated the Nrf-2 pathway, increased NeuN⁺/Nrf-2⁺ cell number in the striatum, induced activation of manganese superoxide dismutase and heme oxygenase-1, and regulated glutathione levels. Moreover, DMF reduced interleukin 1 levels, cyclooxygenase 2 activity, and nitrotyrosine neuronal nitrite oxide synthase expression. This treatment also modulated microglia activation, restored nerve growth factor levels, and preserved microtubule-associated protein 2 alterations. The protective effects of DMF treatment, via Nrf-2, were confirmed in in vitro studies, through inhibition of Nrf-2 by trigonelline.

INNOVATION

These findings demonstrate that DMF, both in a mouse model of PD and in vitro, provides, via regulation of the NF-κB/Nrf-2 pathway, novel cytoprotective modalities that further augment the natural antioxidant response in neurodegenerative and inflammatory disease models.

CONCLUSION

These results support the thesis that DMF may constitute a promising therapeutic target for the treatment of PD. Antioxid. Redox Signal. 27, 453-471.

Recent advances in the biomedical applications of fumaric acid and its ester derivatives: The multifaceted alternative therapeutics

Several lines of evidence have demonstrated the potential biomedical applications of fumaric acid (FA) and its ester derivatives against many human disease conditions. Fumaric acid esters (FAEs) have been licensed for the systemic treatment of the immune-mediated disease psoriasis. Biogen Idec Inc. announced about the safety and efficacy of the formulation FAE (BG-12) for treating RRMS (relapsing-remitting multiple sclerosis). Another FAE formulation DMF (dimethyl fumarate) was found to be capable of reduction in inflammatory cardiac conditions, such as autoimmune myocarditis and ischemia and reperfusion. DMF has also been reported to be effective as a potential neuroprotectant against the HIV-associated neurocognitive disorders (HAND). Many in vivo studies carried out on rat and mice models indicated inhibitory effects of fumaric acid on carcinogenesis of different origins. Moreover, FAEs has emerged as an important matrix ingredient in the fabrication of biodegradable scaffolds for tissue engineering applications. Drug delivery vehicles composed of FAEs have shown promising results in delivering some leading drug molecules. Apart from these specific applications and findings, many more studies on FAEs have revealed new therapeutic potentials with the scope of clinical applications. However, until now, this scattered vital information has not been written into a collective account and analyzed for minute details. The aim of this paper is to review the advancement made in the biomedical application of FA and FAEs and to focus on the clinical investigation and molecular interpretation of the beneficial effects of FA and FAEs.

Treatment With Dimethyl Fumarate Attenuates Calcineurin Inhibitor-induced Nephrotoxicity

BACKGROUND

Cyclosporine A (CsA) is an immunosuppressive drug which has been widely used to prevent rejection after organ transplantation. However, its therapeutic use is limited by nephrotoxicity, in part mediated by oxidative stress. The present study aims to investigate the protective effects of dimethyl fumarate (DMF) on CsA-induced nephrotoxicity by enhancing the antioxidant defense system.

METHODS

Male Sprague-Dawley rats were treated with CsA (n = 8, 20 mg/kg per day intraperitoneally) or CsA + DMF (n = 7, 50 mg/kg per day orally) for 28 days. Renal function, histopathology, malondialdehyde (MDA), myeloperoxidase levels, and antioxidant enzyme expression were determined.

RESULTS

The DMF cotreatment ameliorated CsA-induced renal dysfunction as evidenced by significant decrease in serum creatinine (CsA 0.79 ± 0.02 mg/dL vs CsA + DMF 0.62 ± 0.04 mg/dL, P = 0.001) and urea (CsA 66.9 ± 0.4 mg/dL vs CsA + DMF 53.3 ± 2.6 mg/dl, P < 0.0001) levels, as well as improvement of creatinine clearance. Dimethyl fumarate also significantly decreased serum MDA and renal tissue MDA and myeloperoxidase contents. The protein expression of NAD(P)H quinone oxidoreductase-1, a major cellular antioxidant and detoxifying enzyme, was significantly enhanced by DMF administration in kidney.

CONCLUSIONS

Administration of DMF has a protective potential against CsA nephrotoxicity. The protection afforded by DMF is mediated in part through inhibiting oxidative stress and inflammation and enhancing the antioxidant capacity.

Dimethyl fumarate ameliorates acute pancreatitis in rodent

OBJECTIVES

Pancreatitis is a complex inflammatory disorder, ranging from a mild attack, to severe and potentially fatal condition. Dimethyl fumarate (DMF), a potent antioxidant and anti-inflammatory, has been used medicinally for decades. The purpose of this study was to test the hypothesis that treatment with DMF may ameliorate acute pancreatitis (AP) in a rodent model.

METHODS

Rats were treated with DMF (25 mg/kg) 24 hours prior to AP induction with l-arginine (3 g/kg). At 72 hours, the pancreas was processed for histology. Serum amylase, lactate dehydrogenase, pancreatic trypsin, and lipid peroxidation product (malondialdehyde) were evaluated. Key cytokines and chemokines in the supernatant of lipopolysaccharide-stimulated splenocytes were also determined.

RESULTS

Pancreata from DMF-treated rats showed reductions in the severity of inflammatory cell infiltration, acinar damage, perilobar edema, and cell necrosis. This was associated with significantly lower amylase and malondialdehyde but not lactate dehydrogenase or trypsin levels. The apoptotic pancreatic cells (cleaved caspase 3 positive) were significantly lower in the DMF-treated rats. Lipopolysaccharide-stimulated splenocytes treated with DMF produced a significantly lower amount of key inflammatory mediators.

CONCLUSION

Administration of DMF attenuates AP in rats.

Update on disease-modifying treatments for multiple sclerosis

PURPOSE

The purpose of this review is to discuss the selection and use of disease- modifying treatments for patients with relapsing forms of multiple sclerosis (MS).

METHODS

PubMed was searched (1966-2014) using the terms multiple sclerosis, treatment, interferon, glatiramer acetate, dimethyl fumarate, fingolimod, teriflunomide, natalizumab, rituximab, and alemtuzumab.

FINDINGS

MS is a chronic neurological disorder that can cause a substantial degree of disability. Because of its usual onset in young adults, patients may require treatment for several decades. Currently available agents include platform injectable therapies, newer oral agents, and second-line monoclonal antibody treatments. Treatment decisions have become more complex with the introduction of new approaches, and a major goal is to balance perceived efficacy and tolerability in a specific patient with the relative impact of disease activity and adverse events on quality of life. Here the options for disease-modifying treatments for relapsing forms of MS are reviewed, and current and future challenges are discussed.

IMPLICATIONS

An evidence-based approach can be used for the selection of disease-modifying treatments based on disease phenotype and severity, adverse events, and perceived efficacy.

Dimethyl fumarate protects pancreatic islet cells and non-endocrine tissue in L-arginine-induced chronic pancreatitis

Background

Chronic pancreatitis (CP) is a progressive disorder resulting in the destruction and fibrosis of the pancreatic parenchyma which ultimately leads to impairment of the endocrine and exocrine functions. Dimethyl Fumarate (DMF) was recently approved by FDA for treatment of patients with multiple sclerosis. DMF's unique anti-oxidant and anti-inflammatory properties make it an interesting drug to test on other inflammatory conditions. This study was undertaken to determine the effects of DMF on islet cells and non-endocrine tissue in a rodent model of L-Arginine-induced CP.

Methods

Male Wistar rats fed daily DMF (25 mg/kg) or vehicle by oral gavage were given 5 IP injections of L-Arginine (250 mg/100 g×2, 1 hr apart). Rats were assessed with weights and intra-peritoneal glucose tolerance tests (IPGTT, 2 g/kg). Islets were isolated and assessed for islet mass and viability with flow cytometry. Non-endocrine tissue was assessed for histology, myeloperoxidase (MPO), and lipid peroxidation level (MDA). In vitro assessments included determination of heme oxygenase (HO-1) protein expression by Western blot.

Results

Weight gain was significantly reduced in untreated CP group at 6 weeks. IPGTT revealed significant impairment in untreated CP group and its restoration with DMF therapy (P <0.05). Untreated CP rats had pancreatic atrophy, severe acinar architectural damage, edema, and fatty infiltration as well as elevated MDA and MPO levels, which were significantly improved by DMF treatment. After islet isolation, the volume of non-endocrine tissue was significantly smaller in untreated CP group. Although islet counts were similar in the two groups, islet viability was significantly reduced in untreated CP group and improved with DMF treatment. In vitro incubation of human pancreatic tissue with DMF significantly increased HO-1 expression.

Conclusion

Administration of DMF attenuated L-Arginine-induced CP and islet function in rats. DMF treatment could be a possible strategy to improve clinical outcome in patients with CP.

Dimethyl fumarate: a novel oral front-line therapy for multiple sclerosis treatment

Owing to their immunomodulatory effects and safety profile, fumaric acid esters, such as dimethyl fumarate, are being investigated for the treatment of relapsing–remitting multiple sclerosis. BG-12, an oral formulation of dimethyl fumarate, is rapidly metabolized into its bioactive compound monomethyl fumarate, which displays both anti-inflammatory and neuroprotective properties in animal and in vitro studies. Although the mechanisms underlying the cytoprotective properties of fumaric acid esters are not fully elucidated, evidence is emerging that they act on immunomodulatory and antioxidant pathways. Clinical trials provide compelling evidence for the clinical efficacy of BG-12 in the treatment of relapsing–remitting multiple sclerosis, and have demonstrated that oral administration of BG-12 is well tolerated and markedly reduced the annualized relapse rate, the numbers of gadolinium-enhancing lesions and the number of black holes. Based on its favorable safety, tolerability and neuroprotective properties, BG-12 represents an excellent oral disease-modifying drug in the treatment of multiple sclerosis.

Allergic contact dermatitis from dimethyl fumarate after contact with a Chinese sofa

BACKGROUND

Dimethyl fumarate has been successfully used in the treatment of psoriasis in the past. Despite its clinical use, cutaneous contact with this molecule may cause contact dermatitis.

OBJECTIVE

We report a case in which skin exposure to a synthetic fabric sofa containing dimethyl fumarate made by a Chinese furniture manufacturer resulted in a severe, pruritic, papulovesicular, eczematous dermatitis to the sites of contact with the sofa.

METHODS

The patient was patch-tested with serial dilutions of dimethyl fumarate.

RESULTS

Patch testing results revealed strong positive reactions to dimethyl fumarate at different concentrations.

CONCLUSION

Dimethyl fumarate is a potent contact sensitizer and is commonly found in sachets inside furniture and footwear boxes.

Dimethyl fumarate - only an anti-psoriatic medication?

Fumaric acid esters have been used successfully in the therapy of psoriasis vulgaris since 1959. In the last 17 years, many of the underlying mechanisms of anti-psoriatic action, such as a Th1/Th2 shift, a suppression of important leukocyte adhesion molecules, the induction of pro-apoptotic pathways in T-cells and recently anti-angiogenic action, have been discovered. Based on the knowledge of these immunomodulatory characteristics, fumaric acid esters have been shown to be effective or potentially effective in a multitude of dermatological as well as non-dermatological diseases. The range of new therapeutic targets reaches from multiple sclerosis to illnesses such as necrobiosis lipoidica, granuloma annulare and sarcoidosis. Experimental approaches offer promising, although preliminary, results on the treatment of cancer, malaria, chronic inflammatory lung diseases, and Huntington disease, to name but a few. This valued and well-known drug mainly prescribed by dermatologists is now experiencing a renaissance far beyond dermatologic applications.

The anti-inflammatory effects of dimethyl fumarate in astrocytes involve glutathione and haem oxygenase-1

DMF (dimethyl fumarate) exerts anti-inflammatory and pro-metabolic effects in a variety of cell types, and a formulation (BG-12) is being evaluated for monotherapy in multiple sclerosis patients. DMF modifies glutathione (GSH) levels that can induce expression of the anti-inflammatory protein HO-1 (haem oxygenase-1). In primary astrocytes and C6 glioma cells, BG-12 dose-dependently suppressed nitrite production induced by either LI [LPS (lipopolysaccharide) at 1 μg/ml plus IFNγ (interferon γ) at 20 units/ml] or a mixture of pro-inflammatory cytokines, with greater efficacy in C6 cells. BG-12 reduced NOS2 (nitric oxide synthase 2) mRNA levels and activation of a NOS2 promoter, reduced nuclear levels of NF-κB (nuclear factor κB) p65 subunit and attenuated loss of IκBα (inhibitory κBα) in both cell types, although with greater effects in astrocytes. In astrocytes, LI decreased mRNA levels for GSHr (GSH reductase) and GCL (c-glutamylcysteine synthetase), and slightly suppressed GSHs (GSH synthetase) mRNAs. Co-treatment with BG-12 prevented those decreased and increased levels above control values. In contrast, LI reduced GSHp (GSH peroxidase) and GCL in C6 cells, and BG-12 had no effect on those levels. BG-12 increased nuclear levels of Nrf2 (nuclear factor-erythroid 2 p45 subunit-related factor 2), an inducer of GSH-related enzymes, in astrocytes but not C6 cells. In astrocytes, GSH was decreased by BG-12 at 2 h and increased at 24 h. Prior depletion of GSH using buthionine-sulfoximine increased the ability of BG-12 to reduce nitrites. In astrocytes, BG-12 increased HO-1 mRNA levels and effects on nitrite levels were blocked by an HO-1 inhibitor. These results demonstrate that BG-12 suppresses inflammatory activation in astrocytes and C6 glioma cells, but with distinct mechanisms, different dependence on GSH and different effects on transcription factor activation.

Toll-like receptor signaling pathways and the evidence linking toll-like receptor signaling to cardiac ischemia/reperfusion injury

Toll-like receptors (TLRs) play a key role in innate immune defenses. After activation by foreign pathogens or host-derived molecules, TLRs signal via overlapping or distinct signaling cascades and eventually induce numerous genes involved in a variety of cellular responses. A growing body of evidence suggests that TLR signaling also plays an important role in cardiac ischemia/reperfusion injury. We review our current understanding of the TLR signaling pathways and their roles in the pathophysiology of cardiac ischemia/reperfusion injury, as well as discuss several mechanisms for TLR activation and regulation.

Cytokine signaling in the human brain capillary endothelial cell line hCMEC/D3

Brain microvascular endothelial cells are part of the blood-brain barrier and participate actively in immunological processes including cytokine-mediated inflammatory reactions. Using the human brain capillary endothelial cell line hCMEC/D3, activation of JAK/STAT signaling pathways were studied in response to stimulation by cytokines. The phenotype of hCMEC/D3 cells was confirmed by flow cytometry analysis of cell adhesion factors (cluster of differentiation molecules CD31 and CD34) and the von Willebrand factor endothelial marker was detected by immunofluorescence. Strong STAT1, STAT6 and STAT3 activation was observed in response to interferon-gamma (IFN-gamma), interleukin 4 (IL-4) and interleukin 6 (IL-6), respectively. Nuclear translocation of phosphorylated STAT proteins was visualized by confocal microscopy. Treatment of hCMEC/D3 cells with IFN-gamma resulted in interferon-induced upregulation of major histocompatibility complex (MHC) class I within 48h. Interferon-alpha (IFN-alpha) did not activate STAT1 or STAT3 nor did it induce MHC class I upregulation. Therefore, hCMEC/D3 cells were judged to be non-responsive to IFN-alpha. We also observed that hCMEC/D3 cells exhibit functional expression of alternative cytokine signal transduction pathways (i.e. TNF-alpha mediated activation of NF-kappaB). Together these results indicate that human blood-brain barrier hCMEC/D3 cells are responsive towards stimulation with various cytokines. We conclude that this unique cell line can be used to explore in vitro human blood-brain barrier functionality under proinflammatory conditions.

Effectiveness of chondroitin sulphate in patients with concomitant knee osteoarthritis and psoriasis: a randomized, double-blind, placebo-controlled study

OBJECTIVE

The aim of the trial was to assess the efficacy of chondroitin sulphate (CS) on symptomatic knee osteoarthritis (OA) associated to psoriasis.

METHODS

In this randomized, double-blind, placebo (PBO)-controlled clinical trial 129 patients with symptomatic knee OA and concomitant psoriasis were randomized into two groups receiving 800 mg daily of CS or PBO for 3 months. The primary efficacy outcome for knee OA was the Huskisson's visual analogue scale (VAS) and for psoriasis was the Psoriasis Area and Severity Index (PASI). Additionally, other secondary efficacy criteria for both conditions were assessed.

RESULTS

After 3 months of treatment, CS was more effective than PBO, relieving pain VAS (CS -26.9+/-24.8 vs PBO -14.23+/-20.8mm, P<0.01), decreasing the Lequesne index (CS -4.8+/-3.4 vs PBO -3.3+/-3.5, P<0.05) and reducing the number of patients using acetaminophen as rescue medication (CS 43% vs PBO 64%, P<0.05). Regarding PASI, Overall Lesion Severity Scale and Physician's Global Assessment of Change no statistically significant changes were detected in front of PBO. However, CS improved plantar psoriasis compared to PBO (CS 87% vs PBO 27%, P<0.05). Quality of life improved significantly in CS-treated patients according to the Short Form-36 health survey and the Dermatology Life Quality Index (DLQI). CS tolerability was excellent. Adverse events were infrequent and evenly distributed among groups. The incidence of psoriatic flares did not increase after treatments.

CONCLUSIONS

This study confirms the efficacy and safety of CS as a symptomatic slow-acting drug in patients with knee OA and shows that CS improves plantar psoriasis. The use of CS could represent a special benefit in patients with both pathologies since non-steroidal anti-inflammatory drugs have been reported to induce or exacerbate psoriasis.

Combination of dacarbazine and dimethylfumarate efficiently reduces melanoma lymph node metastasis

Dimethylfumarate (DMF) has been shown to reduce melanoma growth and metastasis in animal models. We addressed the question of whether DMF is as effective in its antitumor activity as the US Food and Drug Administration-approved alkylating agent dacarbazine (DTIC). We also tested the possibility of an improved antitumoral effect when both therapeutics were used together. Using our severe combined immunodeficiency (SCID) mouse model, in which xenografted human melanoma cells metastasize from primary skin sites to sentinel nodes, we show that these treatments, alone or in combination, reduce tumor growth at primary sites. Our main finding was that metastasis to sentinel nodes is significantly delayed only in mice treated with a combination of DTIC and DMF. Subsequent experiments were able to show that a combination of DTIC/DMF significantly reduced lymph vessel density in primary tumors as examined by real-time PCR and immunohistochemistry. In addition, DTIC/DMF treatment significantly impaired melanoma cell migration in vitro. In vivo, DTIC/DMF therapy significantly reduced mRNA expression and protein concentration of the promigratory chemokines CXCL2 and CXCL11. In addition, our data suggest that this xenotransplantation model is suitable for preclinical testing of various combinations of antimelanoma agents.

Immunomodulatory and anti-inflammatory effects of chondroitin sulphate

Chondroitin sulphate (CS) is a natural glycosaminoglycan present in the extracellular matrix and is formed by the 1–3 linkage of D-glucuronic acid to N-acetylgalactosamine. In chondrocytes, CS diminishes interleukin-1 p (IL-1p)-induced increases in p38 mitogen-activated protein kinase (p38MAPK) and signal-regulated kinase 1/2 (Erk1/2) phosphorylation, and decreases nuclear factor-KB (NF-kB) nuclear translocation and as a consequence, reduces the formation of pro-inflammatory cytokines, IL-1 p and TNF-a, and pro-inflammatory enzymes, such as phospholipase A2 (PLA2), cyclooxygenase 2 (COX-2) and nitric oxide synthase-2 (NOS-2). The mechanism of action of CS explains its beneficial effect on the cartilage, synovial membrane and subchondral bone. On the other hand, in vivo, CS given orally prevents hepatic NF-κB nuclear translocation, suggesting that systemic CS may elicit an anti-inflammatory effect in many tissues besides the articulation. There is preliminary evidence showing that in human beings, CS may be of benefit in other diseases where inflammation is an essential marker, such as psoriasis and atherosclerosis. The review of the literature suggest that CS might also be of interest for the treatment of other diseases with an inflammatory and/or autoimmune character, such as inflammatory bowel disease, degenerative diseases of the central nervous system and stroke, multiple sclerosis and other autoimmune diseases.