A review of the mechanisms of action of dimethylfumarate in the treatment of psoriasis

Structure-based molecular hybridization design and synthesis of Keap1-Nrf2 inhibitors for anti-inflammatory treatment

The Kelch-like ECH-associated protein 1 (Keap1)-nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway stands as a pivotal mechanism in defending against oxidative stress damage and related inflammation. Blocking the Keap1-Nrf2 protein-protein interaction (PPI) offers a promising therapeutic approach for treating diseases related to oxidative stress and inflammation. Our group previously reported NXPZ-2, a naphthalene sulfonamide derivative targeting Keap1, which effectively inhibits the Keap1-Nrf2 PPI, thereby releasing Nrf2 to exert its anti-inflammatory and antioxidant effects. In the present work, we employed a structure-based molecular hybridization strategy to design a series of novel naphthalene sulfonamides by combining NXPZ-2 with the Nrf2 activator dimethyl fumarate (DMF) or its analogues. Among these new derivatives, compound 1c, specifically (Z)-4-((4-(N-(2-amino-2-oxoethyl)-N-(4-((N-(2-amino-2-oxoethyl)-4-methoxyphenyl)sulfonamide)naphthalen-1-yl) sulfamoyl)phenyl)amino)-4-oxobut-2-enoic acid, exhibited the highest PPI inhibitory activity, with a KD2 value of 0.119 μM. In an LPS-induced RAW264.7 cell model, this compound mitigated LPS-induced cellular damage, suppressed the expression of pro-inflammatory cytokine TNF-α and IL-6, and significantly elevated the intracellular GSH and SOD enzyme activities. Furthermore, in an LPS-induced acute lung injury (ALI) mouse model, the compound demonstrated a remarkable ability to alleviate oxidative damage and inflammation in the lungs. In conclusion, this novel naphthalene sulfonamide represents a promising drug candidate for Keap1-targeting therapy in ALI. Molecular docking analysis revealed that the amide and maleic acid groups of 1c facilitate strong interactions with the Kelch domain of Keap1, explaining the compound's preference for binding through hydrogen bonding and π-π stacking interactions.

Insights into the itaconate family: Immunomodulatory mechanisms and therapeutic potentials

The itaconate family, comprising itaconate derivatives, endogenous isomers, and other related compounds, has demonstrated substantial immunoregulatory properties. These compounds exhibit significant therapeutic potential in various disease models by modulating metabolic pathways, signal transduction cascades, and post-translational modifications. In this review, we delineate the structural characteristics and biological functions of the members of the itaconate family and elucidate their immunomodulatory mechanisms. Additionally, we summarize the immunomodulatory effects of the itaconate family across various disease categories, including cardiovascular, liver, respiratory, bone and cartilage, neurological, and autoimmune diseases. This review aims to deepen our understanding of the itaconate family and its potential applications, providing new perspectives and therapeutic strategies for inflammatory disorders and autoimmune diseases.

Thirty years of NRF2: advances and therapeutic challenges

Over the last 30 years, NRF2 has evolved from being recognized as a transcription factor primarily involved in redox balance and detoxification to a well-appreciated master regulator of cellular proteostasis, metabolism and iron homeostasis. NRF2 plays a pivotal role in diverse pathologies, including cancer, and metabolic, inflammatory and neurodegenerative disorders. It exhibits a Janus-faced duality, safeguarding cellular integrity in normal cells against environmental insults to prevent disease onset, whereas in certain cancers, constitutively elevated NRF2 levels provide a tumour survival advantage, promoting progression, therapy resistance and metastasis. Advances in understanding the mechanistic regulation of NRF2 and its roles in human pathology have propelled the investigation of NRF2-targeted therapeutic strategies. This Review dissects the mechanistic intricacies of NRF2 signalling, its cross-talk with biological processes and its far-reaching implications for health and disease, highlighting key discoveries that have shaped innovative therapeutic approaches targeting NRF2.

Dimethyl fumarate promotes the degradation of HNF1B and suppresses the progression of clear cell renal cell carcinoma

Clear cell renal cell carcinoma (ccRCC) is the most lethal subtype of renal cancer, and its treatment options remain limited. Therefore, there is an urgent need to discover therapeutic agents for ccRCC treatment. Here, we demonstrate that dimethyl fumarate (DMF), an approved medication for multiple sclerosis [1] and psoriasis, can inhibit the proliferation of ccRCC cells. Mechanistically, hepatocyte nuclear factor 1β (HNF1B), a transcription factor highly expressed in ccRCC, is succinated by DMF at cysteine residues, leading to its proteasomal degradation. Furthermore, HNF1B interacts with and stabilizes Yes-associated protein (YAP), thus DMF-mediated HNF1B degradation decreases YAP protein level and the expression of its target genes, resulting in the suppression of ccRCC cell proliferation. Importantly, oral administration of DMF sensitizes ccRCC to sunitinib treatment and enhances its efficacy in mice. In summary, we provide evidences supporting DMF as a potential drug for clinical treatment of ccRCC by targeting HNF1B and reveal a previously unrecognized role of HNF1B in regulating YAP in ccRCC.

Electrostimulation: A Promising New Treatment for Psoriasis

Psoriasis is a chronic inflammatory skin disease caused by abnormal activation and immune system disorder. Despite the availability of several treatments, they only provide temporary relief, and there is a critical need for more effective therapies to manage this condition. Electrostimulation has been widely used as a physical stimulus in treating various diseases, and recent studies have shown its potential in psoriasis treatment. In this review, we explore the direct and indirect effects of electrostimulation in treating psoriasis and their underlying mechanisms (the decreased secretion of inflammatory cytokines, the loss of cell-to-cell connections, and the cAMP signaling pathway). Our findings suggest that electrostimulation therapy may offer a promising approach to treating psoriasis and developing wearable devices for its management.

Discovery of Propionic Acid Derivatives with a 5-THIQ Core as Potent and Orally Bioavailable Keap1-Nrf2 Protein-Protein Interaction Inhibitors for Acute Kidney Injury

Keap1 plays a crucial role in regulating the Nrf2-mediated cytoprotective response and is increasingly targeted for oxidative stress-related diseases. Using small molecules to disrupt the Keap1-Nrf2 protein-protein interaction (PPI) has emerged as a new strategy for developing Nrf2 activators. Through extensive structure-activity relationship studies, we identified compound 56, which features a unique 5-tetrahydroisoquinoline scaffold and acts as a potent inhibitor of the Keap1-Nrf2 PPI. Compound 56 exhibited significant inhibitory activity (IC50 = 16.0 nM) and tight Keap1 binding affinity (Kd = 3.07 nM), along with acceptable oral bioavailability (F = 20%). Notably, 56 enhanced antioxidant defenses in HK-2 renal tubular epithelial cells and significantly reduced plasma creatinine and blood urea nitrogen levels in acute kidney injury (AKI) mice. These findings collectively position compound 56 as a promising candidate for the treatment of AKI.

Krebs cycle derivatives, dimethyl fumarate and itaconate, control metabolic reprogramming in inflammatory human microglia cell line

Metabolic reprogramming drives inflammatory activity in macrophages, including microglia, with Krebs cycle (KC) intermediates playing a crucial role as signaling molecules. Here, we show that the bioenergetic profile of LPS-activated human microglialclone 3 cell line (HMC3) is characterized by high levels of glycolysis and mitochondrial (mt) respiration, and the treatment with KC derivatives, namely dimethyl-fumarate (DMF) and itaconate (ITA), almost restores normal metabolism. However, despite comparable bioenergetic and anti-inflammatory effects, the mt hyper-activity was differentially modulated by DMF and ITA. DMF normalized complex I activity, while ITA dampened both complex I and II hyper-activity counteracting oxidative stress more efficiently.

Selective activation of cellular stress response pathways by fumaric acid esters

The cellular response to oxidants or xenobiotics comprises two key pathways, resulting in modulation of NRF2 and FOXO transcription factors, respectively. Both mount a cytoprotective response, and their activation relies on crucial protein thiol moieties. Using fumaric acid esters (FAEs), known thiol-reactive compounds, we tested for activation of NRF2 and FOXO pathways in cultured human hepatoma cells by dimethyl/diethyl as well as monomethyl/monoethyl fumarate. Whereas only the diesters caused acute glutathione depletion and activation of the stress kinase p38MAPK, all four FAEs stimulated NRF2 stabilization and upregulation of NRF2 target genes. However, no significant FAE-induced activation of FOXO-dependent target gene expression was observed. Therefore, while both NRF2 and FOXO pathways are responsive to oxidants and xenobiotics, FAEs selectively activate NRF2 signaling.

Induction of Oxidative Stress and Ferroptosis in Triple-Negative Breast Cancer Cells by Niclosamide via Blockade of the Function and Expression of SLC38A5 and SLC7A11

The amino acid transporters SLC38A5 and SLC7A11 are upregulated in triple-negative breast cancer (TNBC). SLC38A5 transports glutamine, methionine, glycine and serine, and therefore activates mTOR signaling and induces epigenetic modifications. SLC7A11 transports cystine and increases the cellular levels of glutathione, which protects against oxidative stress and lipid peroxidation via glutathione peroxidase, a seleno (Se)-enzyme. The primary source of Se is dietary Se-methionine (Se-Met). Since SLC38A5 transports methionine, we examined its role in Se-Met uptake in TNBC cells. We found that SLC38A5 interacts with methionine and Se-Met with comparable affinity. We also examined the influence of Se-Met on Nrf2 in TNBC cells. Se-Met activated Nrf2 and induced the expression of Nrf2-target genes, including SLC7A11. Our previous work discovered niclosamide, an antiparasitic drug, as a potent inhibitor of SLC38A5. Here, we found SLC7A11 to be inhibited by niclosamide with an IC50 value in the range of 0.1-0.2 μM. In addition to the direct inhibition of SLC38A5 and SLC7A11, the pretreatment of TNBC cells with niclosamide reduced the expression of both transporters. Niclosamide decreased the glutathione levels, inhibited proliferation, suppressed GPX4 expression, increased lipid peroxidation, and induced ferroptosis in TNBC cells. It also significantly reduced the growth of the TNBC cell line MB231 in mouse xenografts.

Potential applications of ferroptosis inducers and regulatory molecules in hematological malignancy therapy

Ferroptosis, a novel form of iron-dependent cell death, has emerged as a potential avenue for promoting tumor cell death by causing cell membrane rupture and the accumulation of lipid peroxides (LPO) in the cell. Since its discovery in 2012, extensive research has been conducted to explore the mechanism of ferroptosis inducers, including erastin, sulfasalazine, and sorafenib. These compounds inhibit system XC-, while Ras-selective lethal small molecule 3 (RSL3) and FION2 specifically target GPX4 to promote ferroptosis. Therefore, targeting ferroptosis presents a promising therapeutic approach for malignant tumors. While the study of ferroptosis in solid tumors has made significant progress, there is limited information available on its role in hematological tumors. This review aims to summarize the molecular mechanisms of ferroptosis inducers and discuss their clinical applications in hematological malignancies. Furthermore, the identification of non-coding RNAs (ncRNAs) and genes that regulate key molecules in the ferroptosis pathway could provide new targets and establish a molecular theoretical foundation for exploring novel ferroptosis inducers in hematological malignancies.

From Plant to Chemistry: Sources of Active Opioid Antinociceptive Principles for Medicinal Chemistry and Drug Design

Pain continues to be an enormous global health challenge, with millions of new untreated or inadequately treated patients reported annually. With respect to current clinical applications, opioids remain the mainstay for the treatment of pain, although they are often associated with serious side effects. To optimize their tolerability profiles, medicinal chemistry continues to study novel ligands and innovative approaches. Among them, natural products are known to be a rich source of lead compounds for drug discovery, and they hold potential for pain management. Traditional medicine has had a long history in clinical practice due to the fact that nature provides a rich source of active principles. For instance, opium had been used for pain management until the 19th century when its individual components, such as morphine, were purified and identified. In this review article, we conducted a literature survey aimed at identifying natural products interacting either directly with opioid receptors or indirectly through other mechanisms controlling opioid receptor signaling, whose structures could be interesting from a drug design perspective.

Desipramine induces eryptosis in human erythrocytes, an effect blunted by nitric oxide donor sodium nitroprusside and N-acetyl-L-cysteine but enhanced by Calcium depletion

Background: Desipramine a representative of tricyclic antidepressants (TCAs) promotes recovery of depressed patients by inhibition of reuptake of neurotransmitters serotonin (SER) and norepinephrine (NE) in the presynaptic membrane by directly blocking their respective transporters SERT and NET.Aims: To study the effect of desipramine on programmed erythrocyte death (eryptosis) and explore the underlying mechanisms.Methods: Phosphatidylserine (PS) exposure on the cell surface as marker of cell death was estimated from annexin-V-binding, cell volume from forward scatter in flow cytometry. Hemolysis was determined photometrically, and intracellular glutathione [GSH]i from high performance liquid chromatography.Results: Desipramine dose-dependently significantly enhanced the percentage of annexin-V-binding cells and didn´t impact glutathione (GSH) synthesis. Desipramine-induced eryptosis was significantly reversed by pre-treatment of erythrocytes with either nitric oxide (NO) donor sodium nitroprusside (SNP) or N-acetyl-L-cysteine (NAC). The highest inhibitory effect was obtained by using both inhibitors together. Calcium (Ca2+) depletion aggravated desipramine-induced eryptosis. Changing the order of treatment, i.e. desipramine first followed by inhibitors, could not influence the inhibitory effect of SNP or NAC.Conclusion: Antidepressants-caused intoxication can be treated by SNP and NAC, respectively. B) Patients with chronic hypocalcemia should not be treated with tricyclic anti-depressants or their dose should be noticeably reduced.

Therapeutic Management of a Case of Severe Psoriasis Coexistent with Bullous Pemphigoid in the Elderly

A standardised therapeutic approach to coexistent psoriasis and bullous pemphigoid is lacking, although psoriasis is associated with an increased risk of developing bullous pemphigoid. Here, we report an elderly psoriatic patient who developed a refractory bullous pemphigoid and experienced clearance of both diseases following treatment with dymethylfumarate. Due to lymphopenia, this treatment was stopped and the patient was administered risankizumab without relapses. Dymethylfumarate may be able to inhibit the recruitment of neutrophils and monocytes into the skin. Therefore, thanks to pleiotropic effects, dymethylfumarate could be an effective treatment in psoriatic patients who develop bullous pemphigoid.

Novel Gastroprotective and Thermostable Cocrystal of Dimethyl Fumarate: Its Preparation, Characterization, and In Vitro and In Vivo Evaluation

Crystallization has revolutionized the field of solid-state formulations by modulating the physiochemical and release profile of active pharmaceutical ingredients (APIs). Dimethyl fumarate (DF), an FDA-approved first-line drug for relapsing-remitting multiple sclerosis, has a sublimation problem, leading to loss of the drug during its processing. To tackle this problem, DF cocrystal has been prepared by using solvent evaporation technique using nicotinamide as a coformer, which has been chosen based on in silico predictions and their ability to participate in hydrogen bonding. Fourier transform infrared (FT-IR), powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and sublimation analysis have characterized the cocrystal and its thermostability. Comparative analysis of the release profile has been done by the dissolution and pharmacokinetic study of DF and its cocrystal. Formulated cocrystal is noncytotoxic, antioxidant and inhibits interleukin-6 and tissue necrosis factor-α in peripheral blood mononuclear cells induced by lipopolysaccharide. We have obtained a thermostable cocrystal of DF with a similar physicochemical and release profile to that of DF. The formulated cocrystal also provides a gastroprotective effect which helps counterbalance the adverse effects of DF by reducing lipid peroxidation and total nitrite levels.

Mechanism of action and therapeutic potential of dimethyl fumarate in ischemic stroke

Dimethyl fumarate (DMF) is an immunomodulatory drug currently approved for the treatment of multiple sclerosis and psoriasis. Its benefits on ischemic stroke outcomes have recently come to attention. To date, only tissue plasminogen activators (tPAs) and clot retrieval methods have been approved by the FDA for the treatment of ischemic stroke. Ischemic conditions lead to inflammation through diverse mechanisms, and recanalization can worsen the state. DMF and the nuclear factor erythroid-derived 2-related factor 2 (Nrf2) pathway it regulates seem to be important in postischemic inflammation, and animal studies have demonstrated that the drug improves overall stroke outcomes. Although the exact mechanism is still unknown, studies indicate that these beneficial impacts are due to the modulation of immune responses, blood-brain barrier permeability, and hemodynamic adjustments. One major component evaluated before, during, and after tPA therapy in stroke patients is blood pressure (BP). Recent studies have found that DMF may impact BP. Both hypotension and hypertension need correction before treatment, which may delay the appropriate intervention. Since BP management is crucial in managing stroke patients, it is important to consider DMF's role in this matter. That being said, it seems further investigations on DMF may lead to an alternative approach for stroke patients. In this article, we discuss the mechanistic roles of DMF and its potential role in stroke based on previously published literature and laboratory findings.

d-mannose blocks the interaction between keratinocytes and Th17 cells to alleviate psoriasis by inhibiting HIF-1α/CCL20 in mice

Psoriasis is an autoimmune chronic inflammatory skin disease with an unclear pathogenesis that is difficult to cure, causing serious physical and mental burdens for patients. Previous research showed that a mutually reinforcing vicious cycle caused by keratinocytes (KC) and a variety of immune cells plays an important role in psoriatic inflammation. d-Mannose, a widely distributed metabolite in the body, has been found to treat several metabolic diseases, but its impact on psoriasis remains unknown. Our study aims to investigate the effects of d-mannose on psoriasis and its specific mechanism. Here, we found that d-mannose alleviates psoriasis in mice both as oral and topical agents. Specifically, d-mannose down-regulated the expression of hypoxia-inducible factor 1A(HIF-1α) and inhibited the expression of chemokine CCL20 in keratinocytes, thereby inhibiting the local infiltration of Th17 cells and breaking the cycle of keratinocytes-Th17 cells. Overall, our study indicates that d-mannose alleviates cutaneous inflammation in psoriasis by inhibiting the HIF-1α/CCL20/Th17 cells axis, and d-mannose has the potential to be used as an oral and topical agent in the treatment of psoriasis.

GATA6 coordinates cross-talk between BMP10 and oxidative stress axis in pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is a life-threatening condition characterized by a progressive increase in pulmonary vascular resistance leading to right ventricular failure and often death. Here we report that deficiency of transcription factor GATA6 is a shared pathological feature of PA endothelial (PAEC) and smooth muscle cells (PASMC) in human PAH and experimental PH, which is responsible for maintenance of hyper-proliferative cellular phenotypes, pulmonary vascular remodeling and pulmonary hypertension. We further show that GATA6 acts as a transcription factor and direct positive regulator of anti-oxidant enzymes, and its deficiency in PAH/PH pulmonary vascular cells induces oxidative stress and mitochondrial dysfunction. We demonstrate that GATA6 is regulated by the BMP10/BMP receptors axis and its loss in PAECs and PASMC in PAH supports BMPR deficiency. In addition, we have established that GATA6-deficient PAEC, acting in a paracrine manner, increase proliferation and induce other pathological changes in PASMC, supporting the importance of GATA6 in pulmonary vascular cell communication. Treatment with dimethyl fumarate resolved oxidative stress and BMPR deficiency, reversed hemodynamic changes caused by endothelial Gata6 loss in mice, and inhibited proliferation and induced apoptosis in human PAH PASMC, strongly suggesting that targeting GATA6 deficiency may provide a therapeutic advance for patients with PAH.

Isostearic acid is an active component of imiquimod formulations used to induce psoriaform disease models

Topical imiquimod based creams are indicated as immune stimulants for papillomas and various skin neoplasms. Imiquimod is considered a TLR7 ligand. These creams are also used in research to induce skin inflammation in mice as a model for psoriasis. We observed that this inflammatory response was not strictly imiquimod dependent and we set out to establish which components drive the proinflammatory effects. To this end, we examined the induction response in a BALB/cJRj mouse model, in which 50 mg of cream is applied to 2 cm² of skin (125 mg/kg imiquimod-5% W/V, and/or 625 mg/kg isostearic acid-25% W/V). Comparing cream formulations containing isostearic acid, imiquimod and the combination, we observed that isostearic acid causes skin inflammation within 2 days, whereas imiquimod requires up to 5 days for initial signs. Isostearic acid activated an inflammasome response, stimulated release of proinflammatory cytokines and upregulated the IL-23/17 axis. Animals treated with isostearic acid had enlarged livers (+ 40% weight), which was not observed with imiquimod alone. Imiquimod was readily metabolized and cleared from plasma and liver, but was maintained at high levels in the skin throughout the body (200 mM at area of application; 200 µM in untreated skin). Imiquimod application was associated with splenomegaly, cytokine induction/release and initial body weight loss over 3 days. Despite high imiquimod skin levels throughout the animal, inflammation was only apparent in the treated areas and was less severe than in isostearic acid groups. As the concentrations in these areas are well above the 10 µM required for TLR7 responses in vitro, there is an implication that skin inflammation following imiquimod is due to effects other than TLR7 agonism (e.g., adenosine receptor agonism). In brain, isostearic caused no major changes in cytokine expression while imiquimod alone sightly stimulated expression of IL-1β and CCL9. However, the combination of both caused brain induction of CCL3, -9, CXCL10, -13, IL-1β and TNFα. The implication of these data is that isostearic acid facilitates the entry of imiquimod or peripherally secreted cytokines into the brain. Our data suggest that psoriaform skin responses in mice are more driven by isostearic acid, than generally reported and that the dose and route used in the model, leads to profound systemic effects, which may complicate the interpretation of drug effects in this model.

NRF2 Shortage in Human Skin Fibroblasts Dysregulates Matrisome Gene Expression and Affects Collagen Fibrillogenesis

NRF2 is a master regulator of the antioxidative response that was recently proposed as a potential regulator of extracellular matrix (ECM) gene expression. Fibroblasts are major ECM producers in all connective tissues, including the dermis. A better understanding of NRF2-mediated ECM regulation in skin fibroblasts is thus of great interest for skin homeostasis maintenance and aging protection. In this study, we investigate the impact of NRF2 downregulation on matrisome gene expression and ECM deposits in human primary dermal fibroblasts. RNA-sequencing‒based transcriptome analysis of NRF2 silenced dermal fibroblasts shows that ECM genes are the most regulated gene sets, highlighting the relevance of the NRF2-mediated matrisome program in these cells. Using complementary light and electron microscopy methods, we show that NRF2 deprivation in dermal fibroblasts results in reduced collagen I biosynthesis and impacts collagen fibril deposition. Moreover, we identify ZNF469, a putative transcriptional regulator of collagen biosynthesis, as a target of NRF2. Both ZNF469 silenced fibroblasts and fibroblasts derived from Brittle Corneal Syndrome patients carrying variants in ZNF469 gene show reduced collagen I gene expression. Our study shows that NRF2 orchestrates matrisome expression in human skin fibroblasts through direct or indirect transcriptional mechanisms that could be prioritized to target dermal ECM homeostasis in health and disease.

Short-term exposure to dimethyl fumarate (DMF) inhibits LPS-induced IκBζ expression in macrophages

Background: The pharmacological activity of dimethyl fumarate (DMF) in treating psoriasis and multiple sclerosis (MS) is not fully understood. DMF is hydrolysed to monomethyl fumarate (MMF) in vivo, which is believed to account for the therapeutic effects of DMF. However, previous studies have provided evidence that DMF also enters the circulation. Given that DMF is short-lived in the blood, whether DMF has a therapeutic impact is still unclear. Methods: Lipopolysaccharide (LPS)-mediated RAW264.7 cell activation was used as a model of inflammation to explore the anti-inflammatory effects of short-term DMF exposure in vitro. Whole blood LPS stimulation assay was applied to compare the anti-inflammatory effects of DMF and MMF in vivo. Griess assay was performed to examined nitrite release. The expression of pro-inflammatory cytokines and transcription factors were measured by quantitative PCR (qPCR), ELISA and Western blot. Depletion of intracellular glutathione (GSH) was evaluated by Ellman's assay. Luciferase reporter assays were performed to evaluate DMF effects on Nrf2-ARE pathway activation, promoter activity of Nfkbiz and mRNA stability of Nfkbiz. Binding of STAT3 to the IκBζ promoter were examined using Chromatin immunoprecipitation (ChIP) assay. Results: Short-term exposure to DMF significantly inhibited the inflammatory response of RAW264.7 cells and suppressed LPS-induced IκBζ expression. Importantly, oral DMF but not oral MMF administration significantly inhibited IκBζ transcription in murine peripheral blood cells. We demonstrated that the expression of IκBζ is affected by the availability of intracellular GSH and regulated by the transcription factor Nrf2 and STAT3. DMF with strong electrophilicity can rapidly deplete intracellular GSH, activate the Nrf2-ARE pathway, and inhibit the binding of STAT3 to the IκBζ promoter, thereby suppressing IκBζ expression in macrophages. Conclusion: These results demonstrate the rapid anti-inflammatory effects of DMF in macrophages, providing evidence to support the direct anti-inflammatory activity of DMF.

Dimethyl fumarate attenuates paraquat-induced pulmonary oxidative stress, inflammation and fibrosis in mice

Paraquat (PQ) is the most important cationic bipyridyl herbicide in the agricultural industry, which is very toxic to humans and animals and causes disruption in many organs, mainly in the lungs. Dimethyl fumarate (DMF) is an immune-modulating drug used in the treatment of multiple sclerosis and psoriasis shows antioxidant, anti-inflammatory, and antifibrotic effects. In this study, the ameliorative effects of DMF (10, 30 and 100 mg/kg, orally) on PQ (30 mg/kg) model of lung damage were evaluated in male mice. DMF was given daily for 7 days and PQ was administrated in the fourth day in a single dose. On the eighth day, the animals were sacrificed, and their lung tissue were removed. The results indicated that DMF can ameliorate PQ-induced the significant increase in lung index, hydroxyproline, as well as TBARS, TGF-β, NF-κB and decrease in the amount of total thiol, catalase, glutathione peroxidase, superoxide dismutase, Nrf-2, and INF-γ. The histopathological results confirmed indicated findings. The results showed that the protective effect of DMF on PQ-induced toxicity is mediated through antioxidant, anti-inflammatory and antifibrotic activities.

NRF2 in dermo-cosmetic: From scientific knowledge to skin care products

The skin is the organ that is most susceptible to the impact of the exposome. Located at the interface with the external environment, it protects internal organs through the barrier function of the epidermis. It must adapt to the consequences of the harmful effects of solar radiation, the various chemical constituents of atmospheric pollution, and wounds associated with mechanical damage: oxidation, cytotoxicity, inflammation, and so forth. In this biological context, a capacity to adapt to the various stresses caused by the exposome is essential; otherwise, more or less serious conditions may develop accelerated aging, pigmentation disorders, atopy, psoriasis, and skin cancers. Nrf2-controlled pathways play a key role at this level. Nrf2 is a transcription factor that controls genes involved in oxidative stress protection and detoxification of chemicals. Its involvement in UV protection, reduction of inflammation in processes associated with healing, epidermal differentiation for barrier function, and hair regrowth, has been demonstrated. The modulation of Nrf2 in the skin may therefore constitute a skin protection or care strategy for certain dermatological stresses and disorders initiated or aggravated by the exposome. Nrf2 inducers can act through different modes of action. Keap1-dependent mechanisms include modification of the cysteine residues of Keap1 by (pro)electrophiles or prooxidants, and disruption of the Keap1-Nrf2 complex. Indirect mechanisms are suggested for numerous phytochemicals, acting on upstream pathways, or via hormesis. While developing novel and safe Nrf2 modulators for skin care may be challenging, new avenues can arise from natural compounds-based molecular modeling and emerging concepts such as epigenetic regulation.

Real-world use of dimehtyl fumarate in patients with plaque psoriasis: a Delphi-based expert consensus

Dimethyl fumarate (DMF) was recently approved by the European Medicines Agency for systemic treatment of moderate-to-severe chronic plaque psoriasis. Appropriate management of DMF treatment is required to achieve optimal clinical benefits. Seven dermatology experts gathered online for three meetings to identify consensus on use of DMF in patient selection, drug dosage/titration, side effects management, and follow-up, with the aim to provide guidance on use of DMF for psoriasis in clinical dermatological practice based on literature data and expert opinion. Twenty statements were discussed and voted on using a facilitator-mediated modified Delphi methodology. Strong consensus was reached for all statements (agreement level of 100%). DMF treatment is characterized by dosage flexibility, sustained efficacy, high rates of drug survival, and low potential for drug–drug interactions. It can be used in a broad range of patients, including the elderly or those with comorbidities. Side effects (mainly gastrointestinal disorders, flushing, and lymphopenia) are frequently reported but are generally mild and transient and can be minimized by dosage adjustments and slow titration schedule. Hematologic monitoring throughout treatment course is required to reduce the risk of lymphopenia. This consensus document provides clinical dermatologists with answers on optimal use of DMF to treat psoriasis.

The Challenge of Dimethyl Fumarate Repurposing in Eye Pathologies

Dimethyl fumarate (DMF) is a small molecule currently approved and used in the treatment of psoriasis and multiple sclerosis due to its immuno-modulatory, anti-inflammatory, and antioxidant properties. As an Nrf2 activator through Keap1 protein inhibition, DMF unveils a potential therapeutical use that is much broader than expected so far. In this comprehensive review we discuss the state-of-art and future perspectives regarding the potential repositioning of this molecule in the panorama of eye pathologies, including Age-related Macular Degeneration (AMD). The DMF's mechanism of action, an extensive analysis of the in vitro and in vivo evidence of its beneficial effects, together with a search of the current clinical trials, are here reported. Altogether, this evidence gives an overview of the new potential applications of this molecule in the context of ophthalmological diseases characterized by inflammation and oxidative stress, with a special focus on AMD, for which our gene-disease (KEAP1-AMD) database search, followed by a protein-protein interaction analysis, further supports the rationale of DMF use. The necessity to find a topical route of DMF administration to the eye is also discussed. In conclusion, the challenge of DMF repurposing in eye pathologies is feasible and worth scientific attention and well-focused research efforts.

Efficacy and Safety of Dimethyl Fumarate in Patients with Moderate-to-Severe Plaque Psoriasis: Results from a 52-Week Open-Label Phase IV Clinical Trial (DIMESKIN 1)

INTRODUCTION

Although dimethyl fumarate (DMF) has been approved since 2017 for treatment of moderate-to-severe plaque psoriasis, limited data on its safety and efficacy are available in clinical practice. The objective was to assess the efficacy and safety of DMF in patients with moderate-to-severe plaque psoriasis through 52 weeks in conditions close to real clinical practice.

METHODS

DIMESKIN 1 was a 52-week, open-label, phase IV clinical trial conducted at 36 Spanish sites. Adults with diagnosis of moderate-to-severe plaque psoriasis, treated with DMF as per its summary of product characteristics and with ≥ 1 post-baseline Psoriasis Area and Severity Index (PASI) value were included [intention-to-treat (ITT) population]. Efficacy analyses were performed for ITT population and are based on multiple imputation.

RESULTS

Overall, 282 and 274 patients were included in the safety and ITT populations, respectively. At week 24, 46.0%/24.8%/10.9% of patients achieved PASI 75/90/100 response, respectively. At week 52, these percentages were 46.0%/21.9%/10.9%, respectively. Mean body surface area affected decreased from 17.4% to 6.9%/7.3% after 24/52 weeks (p < 0.001, both). A total of 42.9%/49.4% of patients had a Physician's Global Assessment 0-1 at week 24/52, respectively. Mean pruritus visual analogue scale (VAS) significantly decreased after 24 and 52 weeks (p < 0.001, both), with 56.5% and 67.6% of patients, respectively, rating a pruritus VAS < 3. At week 24/52, 61.3%/73.4% patients had a Dermatology Life Quality Index (DLQI) ≤ 5 and 34.7%/32.1% had a DLQI 0-1. The most frequent adverse events were gastrointestinal disorders (mainly diarrhea/abdominal pain in 50.0%/35.1% of patients, respectively), flushing (28.0%), and lymphopenia (31.2%), mostly mild/moderate.

CONCLUSIONS

DMF significantly improves main severity and extension indexes and rates, as well as patient-reported outcomes such as pruritus and quality of life in patients with moderate-to-severe psoriasis after 24 weeks of treatment. These improvements are sustained through 52 weeks. The safety profile of DMF is similar to that previously described for fumarates.

EUDRACT NUMBER

2017-00136840.

Identification of galectin-1 and other cellular targets of alpha,beta-unsaturated carbonyl compounds, including dimethylfumarate, by use of click-chemistry probes

α,β-Unsaturated carbonyls are a common motif in environmental toxins (e.g. acrolein) as well as therapeutic drugs, including dimethylfumarate (DMFU) and monomethylfumarate (MMFU), which are used to treat multiple sclerosis and psoriasis. These compounds form adducts with protein Cys residues as well as other nucleophiles. The specific targets ('adductome') that give rise to their therapeutic or toxic activities are poorly understood. This is due, at least in part, to the absence of antigens or chromophores/fluorophores in these compounds. We have recently reported click-chemistry probes of DMFU and MMFU (Redox Biol., 2022, 52, 102299) that allow adducted proteins to be visualized and enriched for further characterization. In the current study, we hypothesized that adducted proteins could be 'clicked' to agarose beads and thereby isolated for LC-MS analysis of DMFU/MMFU targets in primary human coronary artery smooth muscle cells. We show that the probes react with thiols with similar rate constants to the parent drugs, and give rise to comparable patterns of gene induction, confirming similar biological actions. LC-MS proteomic analysis identified ∼2970 cellular targets of DMFU, ∼1440 for MMFU, and ∼140 for the control (succinate-probe) treated samples. The most extensively modified proteins were galectin-1, annexin-A2, voltage dependent anion channel-2 and vimentin. Other previously postulated DMFU targets, including glyceraldehyde-3-phosphate dehydrogenase (GAPDH), cofilin, p65 (RELA) and Keap1 were also identified as adducted species, though at lower levels with the exception of GAPDH. These data demonstrate the utility of the click-chemistry approach to the identification of cellular protein targets of both exogenous and endogenous compounds.

Serum 3-phenyllactic acid level is reduced in benign multiple sclerosis and is associated with effector B cell ratios

BACKGROUND

3-phenyllactic acid (PLA) is produced by both intestinal bacteria and the human host. PLA exists in its D- and L- chiral forms. It modulates human immune functions, thereby acting as a mediator of bacterial-host interactions. We aim to determine the amount and potential influence of PLA on clinical and immunological features of MS.

METHODS

We measured D- and L-PLA levels in bacterial supernatants and in sera of 60 MS patients and 25 healthy controls. We investigated potential associations between PLA levels, clinical features of MS, serum cytokine levels and ratios of peripheral blood lymphocyte subsets.

RESULTS

Multiple gut commensal bacteria possessed the capacity to generate D- and L-PLA. MS patients with benign phenotype showed markedly lower PLA levels than healthy controls or other MS patients. Fingolimod resistant patients had higher PLA levels at baseline. Furthermore, MS patients with higher PLA levels tended to display increased memory B and plasma cell ratios, elevated IL-4 levels and increased ratios of IL-4 and IL-10 producing T cell subsets.

CONCLUSION

Collectively, our work indicates that reduced serum levels of PLA could be associated with a favorable clinical course in MS and possibly be used as a biomarker.

Electrophile versus oxidant modification of cysteine residues: Kinetics as a key driver of protein modification

Humans have widespread exposure to both oxidants, and soft electrophilic compounds such as alpha,beta-unsaturated aldehydes and quinones. Electrophilic motifs are commonly found in a drugs, industrial chemicals, pollutants and are also generated via oxidant-mediated degradation of biomolecules including lipids (e.g. formation of 4-hydroxynonenal, 4-hydroxyhexenal, prostaglandin J2). All of these classes of compounds react efficiently with Cys residues, and the particularly the thiolate anion, with this resulting in Cys modification via either oxidation or adduct formation. This can result in deleterious or beneficial effects, that are either reversible (e.g. in cell signalling) or irreversible (damaging). For example, acrolein is a well-established toxin, whereas dimethylfumarate is used in the treatment of multiple sclerosis and psoriasis. This short review discusses the targets of alpha,beta-unsaturated aldehydes, and particularly two prototypic cases, acrolein and dimethylfumarate, and the factors that control the selectivity and kinetics of reaction of these species. Comparison is made between the reactivity of oxidants versus soft electrophiles. These rate constants indicate that electrophiles can be significant thiol modifying agents in some situations, as they have rate constants similar to or greater than species such as H₂O₂, can be present at higher concentrations, and are less efficiently removed by protective systems when compared to H₂O₂. They may also induce similar or higher levels of modification than highly reactive oxidants, due to the very low concentrations of oxidants formed in most in vivo situations.

Response to fumaric acid esters for plaque type psoriasis in real-world practice is largely independent of patient characteristics at baseline - a multivariable regression analysis from the German psoriasis registry PsoBest

OBJECTIVES

Fumaric acid esters (FAEs) are a well-established treatment option for long-term therapy of moderate to severe plaque psoriasis. This study examines effectiveness of FAEs for the treatment of plaque psoriasis in real-world practice at 12 months and if patient characteristics affect the odds of clinical response.

METHODS

A descriptive, multivariable logistic regression analysis was conducted in a cohort drawn from the German registry PsoBest. Baseline patient characteristics were assessed as potential treatment effect modifiers.

RESULTS

444 patients (mean age 47.0 years, 39.0% female) were eligible for response analysis using nonresponder imputation at month 12. Of these, 39.6% achieved clinical response, i.e., Psoriasis Area and Severity Index (PASI) ≤3 or skin clearance. In logistic regression analysis (R² = 0.114), only baseline PASI was a significant factor: patients with PASI <10 had a 4 times higher odds (p ≤ 0.001, OR 4.088), patients with PASI of 10-20 a twofold higher odds of response (p ≤ 0.044, OR 1.961) compared to those with PASI >20. Neither sex, age, body weight, disease duration, comorbidity nor pre-treatment had an impact on the odds of response (p > 0.05).

CONCLUSIONS

FAEs showed a favorable response at 12 months, largely independent of patient characteristics.

Dimethyl Fumarate as Therapeutic Alternative in Moderate-to-Severe Psoriasis: Our Experience

Purpose

Dimethyl fumarate (DMF) is an oral formulation approved for the treatment of moderate-to-severe psoriasis in adult patients requiring systemic therapy. Here, we describe our clinical experience with DMF for moderate-to-severe psoriasis in Spain.

Patients and Methods

This is a retrospective study including 30 adult patients with moderate-to-severe psoriasis under treatment with DMF between September 2018 and January 2020. Patients were treated with DMF as per its Summary of Product Characteristics and the median duration of treatment was 15 weeks (4-55 weeks). Psoriasis Area and Severity Index (PASI) and body surface area (BSA) severity scales were evaluated from baseline to week 36 and adverse events (AEs) developed during treatment were described.

Results

The efficacy of DMF was assessed at week 8 and at week 36 (n = 5), both PASI and BSA were 0. At week 24, median PASI showed a decrease in both the last observation carried forward (LOCF; n = 23) and the observed cases (OC) (n = 10): from 10 to 6 and from 10 to 1.5, respectively. Median BSA also showed a decrease from 19 to 10 in LOCF and from 17 to 3 in OC. The most frequent AEs were diarrhoea (40.0%), flushing (13.3%) and lymphopenia (3.3%). In 47.1% patients, AEs have been solved by adjusting the DMF dose. Treatment discontinuation rate due to AEs was 43.3%.

Conclusion

Our clinical experience indicates that DMF could be an effective and safe treatment for moderate-to-severe psoriasis in adult patients.

Combining metabolic phenotype determination with metabolomics and transcriptional analyses to reveal pathways regulated by hydroxycarboxylic acid receptor 2

BACKGROUND

The adaptation of cellular metabolism is considered a hallmark of cancer. Oncogenic signaling pathways support tumorigenesis and cancer progression through the induction of certain metabolic phenotypes associated with altered regulation of key metabolic enzymes. Hydroxycarboxylic acid receptor 2 (HCA₂) is a G protein-coupled receptor previously shown to act as a tumor suppressor. Here, we aimed to unveil the connection between cellular metabolism and HCA₂ in BT-474 cells. Moreover, we intend to clarify how well this metabolic phenotype is reflected in transcriptional changes and metabolite levels as determined by global metabolomics analyses.

METHODS

We performed both, siRNA mediated knockdown of HCA₂ and stimulation with the HCA₂-specific agonist monomethyl fumarate. Seahorse technology was used to determine the role of HCA₂ in BT-474 breast cancer cell metabolism and its potential to induce a switch in the metabolic phenotype in the presence of different energy substrates. Changes in the mRNA expression of metabolic enzymes were detected with real-time quantitative PCR (RT-qPCR). Untargeted liquid chromatography-mass spectrometry (LC-MS) metabolic profiling was used to determine changes in metabolite levels.

RESULTS

Knockdown or stimulation of HCA₂ induced changes in the metabolic phenotype of BT474 cells dependent on the availability of energy substrates. The presence of HCA₂ was associated with increased glycolytic flux with no fatty acids available. This was reflected in the increased mRNA expression of the glycolytic enzymes PFKFB4 and PKM2, which are known to promote the Warburg effect and have been described as prognostic markers in different types of cancer. With exogenous palmitate present, HCA₂ caused elevated fatty acid oxidation and likely lipolysis. The increase in lipolysis was also detectable at the transcriptional level of ATGL and the metabolite levels of palmitic and stearic acid.

CONCLUSIONS

We combined metabolic phenotype determination with metabolomics and transcriptional analyses and identified HCA₂ as a regulator of glycolytic flux and fatty acid metabolism in BT-474 breast cancer cells. Thus, HCA₂, for which agonists are already widely used to treat diseases such as psoriasis or hyperlipidemia, may prove useful as a target in combination cancer therapy.

Disproportional increase in psoriasis reports in association with B cell depleting therapies in patients with multiple sclerosis

BACKGROUND

Some pathways involved in the pathogenesis of psoriasis share similarities with processes involved in multiple sclerosis (MS) pathogenesis. However, the association between MS and psoriasis is poorly understood. Since disease-modifying therapies for MS have various targets, it may be possible that the occurrence of psoriasis varies by drug.

OBJECTIVE

To analyze the frequency of psoriasis reports in patients treated with various disease-modifying therapies for MS.

METHODS

Data was collected using the FDA Adverse Event Reporting System (FAERS) and OpenFDA database between January 2009 and June 2020. The study analyzed total reports of psoriasis out of total reports in the "Skin and Subcutaneous Tissue Disorders" category for each drug and explored age, sex distribution, and report source. OpenFDA data was used to perform statistical analyses including reporting odds ratios (ROR) and information components.

RESULTS

The study identified 517 psoriasis reports of 45,547 total skin and subcutaneous tissue disorders (1.13%) in FAERS. The highest proportions of reports in this study were associated with rituximab, ocrelizumab, and interferon beta 1a. The lowest proportion of reports were associated with glatiramer acetate, alemtuzumab, dimethyl fumarate and teriflunomide. Reports of other autoimmune skin disorders were minimal (29 vitiligo, 33 pemphigoid, and 7 pemphigus). Patients primarily drove reports for most DMTs versus healthcare providers. The proportion of reports from female patients were the highest for each DMT except alemtuzumab. OpenFDA query retrieved 302 total reports of psoriasis. Significantly increased reporting odds ratios (RORs, 95% confidence interval) of psoriasis were noted for rituximab (7.14, 3.92-13.00), ocrelizumab (3.79, 2.74-5.23), and fingolimod (1.33, 1.01-1.76). Significantly decreased RORs were noted for natalizumab (0.53, 0.36-0.80), glatiramer acetate (0.58, 0.35-0.96), and dimethyl fumarate (0.71, 0.53-0.94).

CONCLUSION

There are frequent reports of psoriasis in MS patients treated with various DMTs. However, reports and RORs were disproportionally high in association with B cell depleting therapies. Further research is required to determine if certain DMTs may serve as better options for individuals affected by, or at high-risk for developing psoriasis.

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.

The Role of Glutathione-S Transferase in Psoriasis and Associated Comorbidities and the Effect of Dimethyl Fumarate in This Pathway

Psoriasis vulgaris is a chronic inflammatory skin disease characterized by well-demarcated scaly plaques. Oxidative stress plays a crucial role in the psoriasis pathogenesis and is associated with the disease severity. Dimethyl fumarate modulates the activity of the pro-inflammatory transcription factors. This is responsible for the downregulation of inflammatory cytokines and an overall shift from a pro-inflammatory to an anti-inflammatory/regulatory response. Both steps are necessary for the amelioration of psoriatic inflammation, although additional mechanisms have been proposed. Several studies reported a long-term effectiveness and safety of dimethyl fumarate monotherapy in patients with moderate-to-severe psoriasis. Furthermore, psoriasis is a chronic disease often associated to metabolic comorbidities, as obesity, diabetes, and cardiovascular diseases, in which glutathione-S transferase deregulation is present. Glutathione-S transferase is involved in the antioxidant system. An increase of its activity in psoriatic epidermis in comparison with the uninvolved and normal epidermal biopsies has been reported. Dimethyl fumarate depletes glutathione-S transferase by formation of covalently linked conjugates. This review investigates the anti-inflammatory role of dimethyl fumarate in oxidative stress and its effect by reducing oxidative stress. The glutathione-S transferase regulation is helpful in treating psoriasis, with an anti-inflammatory effect on the keratinocytes hyperproliferation, and in modulation of metabolic comorbidities.

The Nrf2 Pathway in Liver Diseases

Oxidative stress is the leading cause of most liver diseases, such as drug-induced liver injury, viral hepatitis, and alcoholic hepatitis caused by drugs, viruses, and ethanol. The Kelch-like ECH-associated protein 1-NFE2-related factor 2 (Keap1-Nrf2) system is a critical defense mechanism of cells and organisms in response to oxidative stress. Accelerating studies have clarified that the Keap1-Nrf2 axis are involved in the prevention and attenuation of liver injury. Nrf2 up-regulation could alleviate drug-induced liver injury in mice. Moreover, many natural Nrf2 activators can regulate lipid metabolism and oxidative stress of liver cells to alleviate fatty liver disease in mice. In virus hepatitis, the increased Nrf2 can inhibit hepatitis C viral replication by up-regulating hemeoxygenase-1. In autoimmune liver diseases, the increased Nrf2 is essential for mice to resist liver injury. In liver cirrhosis, the enhanced Nrf2 reduces the activation of hepatic stellate cells by reducing reactive oxygen species levels to prevent liver fibrosis. Nrf2 plays a dual function in liver cancer progression. At present, a Nrf2 agonist has received clinical approval. Therefore, activating the Nrf2 pathway to induce the expression of cytoprotective genes is a potential option for treating liver diseases. In this review, we comprehensively summarized the relationships between oxidative stress and liver injury, and the critical role of the Nrf2 pathway in multiple liver diseases.

Dissecting the Crosstalk Between Nrf2 and NF-κB Response Pathways in Drug-Induced Toxicity

Nrf2 and NF-κB are important regulators of the response to oxidative stress and inflammation in the body. Previous pharmacological and genetic studies have confirmed crosstalk between the two. The deficiency of Nrf2 elevates the expression of NF-κB, leading to increased production of inflammatory factors, while NF-κB can affect the expression of downstream target genes by regulating the transcription and activity of Nrf2. At the same time, many therapeutic drug-induced organ toxicities, including hepatotoxicity, nephrotoxicity, cardiotoxicity, pulmonary toxicity, dermal toxicity, and neurotoxicity, have received increasing attention from researchers in clinical practice. Drug-induced organ injury can destroy body function, reduce the patients’ quality of life, and even threaten the lives of patients. Therefore, it is urgent to find protective drugs to ameliorate drug-induced injury. There is substantial evidence that protective medications can alleviate drug-induced organ toxicity by modulating both Nrf2 and NF-κB signaling pathways. Thus, it has become increasingly important to explore the crosstalk mechanism between Nrf2 and NF-κB in drug-induced toxicity. In this review, we summarize the potential molecular mechanisms of Nrf2 and NF-κB pathways and the important effects on adverse effects including toxic reactions and look forward to finding protective drugs that can target the crosstalk between the two.

Non-Alcoholic Fatty Liver Disease (NAFLD) in Patients with Psoriasis: A Review of the Hepatic Effects of Systemic Therapies

There is increasing interest in the association between psoriasis and non-alcoholic fatty liver disease (NAFLD), which is a prevalent liver disease characterized by excessive fat storage and inflammation that can progress to fibrosis and cancer. Patients with psoriasis have a two-fold higher risk to develop NAFLD and a higher risk to progress to more severe liver disease. Psoriasis and NAFLD share common risk factors such as smoking, alcohol consumption, and the presence of metabolic syndrome and its component disorders. In addition, both psoriasis and NAFLD hinge upon a systemic low-grade inflammation that can lead to a vicious cycle of progressive liver damage in NAFLD as well as worsening of the underlying psoriasis. Other important shared pathophysiological pathways include peripheral insulin resistance and oxidative stress. NAFLD should receive clinical awareness as important comorbidity in psoriasis. In this review, we assess the recent literature on the epidemiological and pathophysiological relationship of psoriasis and NAFLD, discuss the clinical implications of NAFLD in psoriasis patients, and summarize the hepatotoxic and hepatoprotective potential of systemic psoriasis therapies.

A Sensitization-Free Dimethyl Fumarate Prodrug, Isosorbide Di-(Methyl Fumarate), Provides a Topical Treatment Candidate for Psoriasis

Dimethyl fumarate (DMF) is an effective oral treatment for psoriasis administered in Europe for nearly 60 years. However, its potential has been limited by contact dermatitis that prohibits topical application. This paper characterizes a DMF derivative, isosorbide DMF (IDMF), which was designed to have antipsoriatic effects without skin-sensitizing properties. We show that IDMF exhibits neither genotoxicity nor radiation sensitivity in skin fibroblasts and is nonirritating and nonsensitizing in animal models (rat, rabbit, guinea pig). Microarray analysis of cytokine-stimulated keratinocytes showed that IDMF represses the expression of genes specifically upregulated in psoriatic skin lesions but not those of other skin diseases. IDMF also downregulated genes induced by IL-17A and TNF in keratinocytes as well as predicted targets of NF-κB and the antidifferentiation noncoding RNA (i.e., ANCR). IDMF further stimulated the transcription of oxidative stress response genes (NQO1, GPX2, GSR) with stronger NRF2/ARE activation compared to DMF. Finally, IDMF reduced erythema and scaling while repressing the expression of immune response genes in psoriasiform lesions elicited by topical application of imiquimod in mice. These data show that IDMF exhibits antipsoriatic activity that is similar or improved compared with that exhibited by DMF, without the harsh skin-sensitizing effects that have prevented topical delivery of the parent molecule.

Dimethyl Fumarate is a Potential Therapeutic Option for Alzheimer's Disease

BACKGROUND

Dimethyl fumarate (DMF) has been approved for clinical treatment of multiple sclerosis based on its antioxidant and anti-inflammatory effects by activating the Nrf2 pathway. Since both oxidative stress and inflammation are involved in Alzheimer's disease (AD), DMF is a potential therapeutic option for AD.

OBJECTIVE

This study aims to test the therapeutic effects of DMF on AD model mice and to reveal its underlying molecular mechanisms.

METHODS

Cell viability assay and in vitro immunofluorescence imaging were used to evaluate the antioxidant effect of DMF on embryonic mouse hippocampal neurons. Behavioral test and brain magnetic resonance imaging were used to assess the therapeutic effects of DMF on spatial learning and memory as well as hippocampal volume in AD model mice with and without Nrf2 knockdown. Western blotting was used to analyze the expression of antioxidant enzymes and molecules associated with AD-related pathological pathways.

RESULTS

DMF inhibits reactive oxygen species overproduction and protects neurons without Nrf2 knockdown from death. DMF reduces amyloid-β induced memory impairment and hippocampal atrophy in AD model mice rather than in Nrf2 knockdown AD mice. DMF delays the progression of AD by activating the Nrf2 pathway to enhance the expression of downstream antioxidant enzymes and inhibits lipid peroxidation, apoptosis, inflammation, mitochondrial dysfunction and amyloid-β deposition.

CONCLUSION

These results indicate that DMF is a potential therapeutic option for AD through its antioxidant, anti-inflammatory, anti-apoptotic, and other anti-AD effects by activating the Nrf2 pathway.

The Defect in Regulatory T Cells in Psoriasis and Therapeutic Approaches

Psoriasis is a chronic inflammatory skin disease characterized by accelerated tumor necrosis factor-α/interleukin (IL)-23/IL-17 axis. Patients with psoriasis manifest functional defects in CD4⁺CD25⁺ forkhead box protein 3 (Foxp3)⁺ regulatory T cells (Tregs), which suppress the excess immune response and mediate homeostasis. Defects in Tregs contribute to the pathogenesis of psoriasis and may attribute to enhanced inhibition and/or impaired stimulation of Tregs. IL-23 induces the conversion of Tregs into type 17 helper T (Th17) cells. IL-17A reduces transforming growth factor (TGF)-β1 production, Foxp3 expression, and suppresses Treg activity. Short-chain fatty acids (SCFAs), butyrate, propionate, and acetate are microbiota-derived fermentation products that promote Treg development and function by inducing Foxp3 expression or inducing dendritic cells or intestinal epithelial cells to produce retinoic acids or TGF-β1, respectively. The gut microbiome of patients with psoriasis revealed reduced SCFA-producing bacteria, Bacteroidetes, and Faecallibacterium, which may contribute to the defect in Tregs. Therapeutic agents currently used, viz., anti-IL-23p19 or anti-IL-17A antibodies, retinoids, vitamin D3, dimethyl fumarate, narrow-band ultraviolet B, or those under development for psoriasis, viz., signal transducer and activator of transcription 3 inhibitors, butyrate, histone deacetylase inhibitors, and probiotics/prebiotics restore the defected Tregs. Thus, restoration of Tregs is a promising therapeutic target for psoriasis.

Spontaneous hydrolysis and spurious metabolic properties of α-ketoglutarate esters

α-ketoglutarate (KG), also referred to as 2-oxoglutarate, is a key intermediate of cellular metabolism with pleiotropic functions. Cell-permeable esterified analogs are widely used to study how KG fuels bioenergetic and amino acid metabolism and DNA, RNA, and protein hydroxylation reactions, as cellular membranes are thought to be impermeable to KG. Here we show that esterified KG analogs rapidly hydrolyze in aqueous media, yielding KG that, in contrast to prevailing assumptions, imports into many cell lines. Esterified KG analogs exhibit spurious KG-independent effects on cellular metabolism, including extracellular acidification, arising from rapid hydrolysis and de-protonation of α-ketoesters, and significant analog-specific inhibitory effects on glycolysis or mitochondrial respiration. We observe that imported KG decarboxylates to succinate in the cytosol and contributes minimally to mitochondrial metabolism in many cell lines cultured in normal conditions. These findings demonstrate that nuclear and cytosolic KG-dependent reactions may derive KG from functionally distinct subcellular pools and sources.

Science's Response to CoVID-19

CoVID-19 is a multi-symptomatic disease which has made a global impact due to its ability to spread rapidly, and its relatively high mortality rate. Beyond the heroic efforts to develop vaccines, which we do not discuss herein, the response of scientists and clinicians to this complex problem has reflected the need to detect CoVID-19 rapidly, to diagnose patients likely to show adverse symptoms, and to treat severe and critical CoVID-19. Here we aim to encapsulate these varied and sometimes conflicting approaches and the resulting data in terms of chemistry and biology. In the process we highlight emerging concepts, and potential future applications that may arise out of this immense effort.

An updated guide in the management of psoriasis for every practitioner

BACKGROUND

Psoriasis is one of the most common chronic cutaneous skin disorders, having genetic and immunological components. It is currently unknown what exactly triggers it, or how far reaching are the etiological factors, although great strides have been made in uncovering the pathophysiological cascade. Presently, there is a wide diversity of treatment methods for psoriasis, yet not all are applicable for each patient. Selection of both drug and dosage depends on both the knowledge and experience of the treating dermatologist and also on the specific characteristics of each patient. Therefore, the treating physicians should be made aware of the management possibilities, their advantages and their side effects.

METHODS

We have performed a non-systematic literature review on the current treatment methods for psoriasis. We have included the studies, articles, and prescription information that provided the most relevant information regarding each therapeutic agent. Afterward, we divided the treatment methods according to delivery and illustrated the management protocols for adult, paediatric, and pregnant patients.

DISCUSSION AND CONCLUSIONS

Current therapies are divided into topical drugs, phototherapy, systemic and biological agents. Topical therapies and phototherapy are generally the first and second line of management respectively, being typically effective in treating mild to moderate forms of psoriasis. On the other hand, the chronic moderate to severe forms usually benefit from systemic drugs, whereas biologic agents are reserved for severe or unremitting cases, especially those suffering from psoriatic arthritis. Also of importance is the understanding of the pathophysiological mechanisms in psoriasis and how the selected drugs interfere in the pathological cascade. Furthermore, physicians should be able to recommend the appropriate therapy not only for adults but also for paediatric and pregnant patients as well. In the following manuscript, we present an updated version of these management options, alongside their indications, posology and most common side effects, a guide that may be useful for every practitioner in this field.

The activation of nuclear factor-E2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) signaling blunts cholestasis-induced liver and kidney injury

Cholestasis is a severe clinical complication that severely damages the liver. Kidneys are also the most affected extrahepatic organs in cholestasis. The pivotal role of oxidative stress has been mentioned in the pathogenesis of cholestasis-induced organ injury. The activation of the nuclear factor-E2-related factor 2 (Nrf2) pathway is involved in response to oxidative stress. The current study was designed to evaluate the potential role of Nrf2 signaling activation in preventing bile acids-induced toxicity in the liver and kidney. Dimethyl fumarate was used as a robust activator of Nrf2 signaling. Rats underwent bile duct ligation surgery and were treated with dimethyl fumarate (10 and 40 mg/kg). Severe oxidative stress was evident in the liver and kidney of cholestatic animals (P < 0.05). On the other hand, the expression and activity of Nrf2 and downstream genes were time-dependently decreased (P < 0.05). Moreover, significant mitochondrial depolarization, decreased ATP levels, and mitochondrial permeabilization were detected in bile duct-ligated rats (P < 0.05). Histopathological alterations included liver necrosis, fibrosis, inflammation and kidney interstitial inflammation, and cast formation. It was found that dimethyl fumarate significantly decreased hepatic and renal injury in cholestatic animals (P < 0.05). Based on these data, the activation of the cellular antioxidant response could serve as an efficient therapeutic option for managing cholestasis-induced organ injury.

Dimethyl fumarate treatment for psoriasis in a real-life setting: A multicentric retrospective study

Dimethyl fumarate (DMF) is a fumaric acid esters derivate approved for plaque psoriasis as first‐line systemic therapy. It has been available in Italy since 2017 and an increasing number of patients are treated with this drug. To evaluate DMF effectiveness, side effects and drug survival in a dermatological real‐life setting. We performed a retrospective multi‐center study in five dermatologic clinics in Emilia‐Romagna, Northern Italy, which included all consecutive patients affected by moderate–severe psoriasis treated with DMF. We assessed effectiveness (in terms of PASI50 and PASI75 in an intention to treat observation) and safety (occurrence of side effects) of DMF and their association with demographic and disease characteristics, mean daily dose taken and treatment discontinuation. We included 103 patients, 78 (75.72%) had at least one comorbidity including 19 (18.44%) with a history of cancer; the mean treatment duration was 23.61 ± 17.99 weeks (min 4, max 130) and the mean daily dose was 262.13 ± 190.94 mg. Twenty‐four patients (23.30%) reached PASI75 at week 12, while a further 18 patients (17.47%) reached it at week 26. Side effects occurred in 63 patients (61.16%), the most frequent were diarrhea, epigastric discomfort, nausea, and flushing. Sixteen patients (15.53%) showed an alteration of laboratory tests. In some cases side effects were transitory, while in 53 patients (51.45%) they led to cessation of therapy. The median daily dose showed a direct association with PASI50 achievement and an indirect association with treatment discontinuation. Our study shows the peculiarities of DMF in a real‐world setting: effectiveness is often reached after 12 weeks of treatment and side effects could limit the continuation of the therapy but, at the same time, DMF has no major contraindications and, due to the wide range of dosage, it can allow both to manage side effects and to personalize the prescription for each patient.

Therapeutic Development Based on the Immunopathogenic Mechanisms of Psoriasis

Psoriasis, a complex inflammatory autoimmune skin disorder that affects 2–3% of the global population, is thought to be genetically predetermined and induced by environmental and immunological factors. In the past decades, basic and clinical studies have significantly expanded knowledge on the molecular, cellular, and immunological mechanisms underlying the pathogenesis of psoriasis. Based on these pathogenic mechanisms, the current disease model emphasizes the role of aberrant Th1 and Th17 responses. Th1 and Th17 immune responses are regulated by a complex network of different cytokines, including TNF-α, IL-17, and IL-23; signal transduction pathways downstream to the cytokine receptors; and various activated transcription factors, including NF-κB, interferon regulatory factors (IRFs), and signal transducer and activator of transcriptions (STATs). The biologics developed to specifically target the cytokines have achieved a better efficacy and safety for the systemic management of psoriasis compared with traditional treatments. Nevertheless, the current therapeutics can only alleviate the symptoms; there is still no cure for psoriasis. Therefore, the development of more effective, safe, and affordable therapeutics for psoriasis is important. In this review, we discussed the current trend of therapeutic development for psoriasis based on the recent discoveries in the immune modulation of the inflammatory response in psoriasis.

Effects of disease-modifying therapy on peripheral leukocytes in patients with multiple sclerosis

Modern disease-modifying therapies (DMTs) in multiple sclerosis (MS) have variable modes of action and selectively suppress or modulate the immune system. In this review, we summarize the predicted and intended as well as unwanted adverse effects on leukocytes in peripheral blood as a result of treatment with DMTs for MS. We link changes in laboratory tests to the possible therapeutic risks that include secondary autoimmunity, infections, and impaired response to vaccinations. Profound knowledge of the intended effects on leukocyte counts, in particular lymphocytes, explained by the mode of action, and adverse effects which may require additional laboratory and clinical vigilance or even drug discontinuation, is needed when prescribing DMTs to treat patients with MS.

Key Signaling Pathways in Psoriasis: Recent Insights from Antipsoriatic Therapeutics

Psoriasis is a common chronic inflammatory skin disease associated with several comorbidities and reduced quality of life. In the past decades, highly effective targeted therapies have led to breakthroughs in the management of psoriasis, providing important insights into the pathogenesis. This article reviews the current concepts of the pathophysiological pathways and the recent progress in antipsoriatic therapeutics, highlighting key targets, signaling pathways and clinical effects in psoriasis.