Introduction
Psoriasis is an immune-mediated inflammatory skin disease characterized by erythematous papules and plaques with overlying white scales. Pathologically, psoriasis is defined by hyperkeratosis, abnormal keratinocyte proliferation, and inflammatory cell infiltration. The global prevalence of psoriasis is estimated to be approximately 2–3% [ 1 ]. Conventional therapies for psoriasis include agents such as calcipotriol, vitamin D analogs and methotrexate. Recent advances in the understanding of psoriasis pathogenesis have facilitated the development of biologic therapies, including agents targeting TNF-α, IL-12, IL-17, and IL-32. Additionally, small-molecule drugs have received significant attention due to their efficacy, lower cost and minimal risk of immune rejection, suggesting that they may serve as important therapeutic options for psoriasis management [ 2 ].
The pathogenesis of psoriasis is complex and remains incompletely understood; however, elevated levels of reactive oxygen species (ROS) and an imbalance in Th1/Th2 immune responses are implicated [ 3 ]. The human skin is the primary barrier against environmental insults and is often subjected to continuous oxidative stress, which increases ROS production due to external stimuli. Persistent oxidative stress, often exacerbated by factors such as substance abuse, immune dysregulation and unhealthy lifestyle choices, is associated with increased psoriasis prevalence [ 4 ]. Excessive ROS can damage DNA, proteins and lipids, activate inflammatory pathways, reduce the body's antioxidant capacity, and impair the function of nuclear factor erythroid 2-related factor 2 (Nrf2). Nrf2, a redox-sensitive transcription factor, has been found to play an important role in the pathogenesis of chronic diseases, including psoriasis [ 5 ]. Under basal conditions, Nrf2 is sequestered in the cytoplasm by Kelch-like ECH-associated protein 1 (Keap1) and undergoes ubiquitination by Cul3 ubiquitin ligase, leading to its proteasomal degradation. However, under oxidative stress, Nrf2 dissociates from Keap1, translocates to the nucleus and upregulates various antioxidant genes [ 6 ]. The activation of Nrf2 has emerged as a promising therapeutic strategy for inflammatory skin diseases, including allergic skin inflammation, atopic dermatitis, and psoriasis [ 7 ]. Currently, two Nrf2 activators have been approved for clinical use: dimethyl fumarate (DMF) for relapsing multiple sclerosis and omaveloxolone for Friedreich's ataxia [ 8 , 9 ]. DMF, a fumarate-based immunomodulator, demonstrates broad pharmacological effects, including antibacterial, anti-inflammatory and neuroprotective properties. After oral administration, DMF is rapidly hydrolyzed to monomethyl fumarate (MMF), the active component of Fumaderm [ 10 , 11 ]. Both DMF and MMF are known to activate the Nrf2 pathway, which enhances the expression of antioxidant enzymes. Related studies have shown that DMF and MMF significantly reduce malondialdehyde (MDA) and ROS levels while increasing superoxide dismutase (SOD) activity, thereby reducing oxidative stress and inflammation in various disease models, including nephropathy, cardiovascular diseases, and neurological disorders [ [12] , [13] , [14] ]. However, MMF's metabolism, primarily in the liver and lungs, is complex and slow, limiting its bioavailability and thus constraining its anti-inflammatory and immunomodulatory effects [ 15 , 16 ].
In the early 20th century, aluminum-adjuvanted antigens were found to elicit stronger humoral immune responses compared to free antigens. Due to their safety and effectiveness in promoting Th2-biased immune responses, alum-based adjuvants have become widely utilized in the medical field [ 17 ]. Aluminum ions were approved by the U.S. Food and Drug Administration as the first metal-based immune adjuvant for human use and have since become one of the most commonly used adjuvants in human vaccines as they provide a stable adsorption surface for antigens [ 18 ]. The binding of antigens to aluminum adjuvant particles occurs through electrostatic interactions and ligand exchange, enhancing antigen stability and facilitating efficient recognition and uptake by antigen-presenting cells (APCs) [ 19 ]. Our group previously investigated the impact of aluminum ions injection on an imiquimod (IMQ)-induced psoriasis-like model. Our findings demonstrated that aluminum ions administration not only inhibited the development of IMQ-mediated Th1 and Th17 immune responses but also suppressed the IMQ-induced recruitment and activation of neutrophils and macrophages [ 20 ]. These results illustrate the capacity of aluminum ions to modulate cutaneous immune responses, offering potential insights into developing new therapeutic approaches for psoriasis.
In this study, we modified the approved drug MMF to form a coordination complex with aluminum ions (MMFAL) to investigate its therapeutic potential for psoriasis. Our findings demonstrate that MMFAL synergistically combines the effects of MMF and aluminum ions, addressing both oxidative damage and immune imbalance implicated in psoriasis pathogenesis. These results provide compelling experimental evidence supporting MMFAL as a novel and effective therapeutic strategy for psoriasis.
Materials and methods
Ethics approval
The clinical serum samples used in this study were collected from patients with written informed consent, and the study protocol was approved by the Ethics Committee of Chongqing Medical University (Approval No. 2024129).
All animal experiments were conducted in accordance with institutional guidelines and approved by the Institutional Animal Care and Use Committee (IACUC) of Chongqing Medical University (Approval No. IACUC-CQMU-20240582).
Chemicals
MMF was purchased from McLean (Shanghai, China; Cat. No. F795443). Aluminum ions were prepared by combining AlCl₃ and NaOH to achieve a pH of 7.0. Calcein AM was purchased from Biyuntian (Shanghai, China; Cat. No. C2012), DCFH₂-DA from MCE (USA; Cat. No. HY-126793), ML385 from MCE (USA; Cat. No. HY-100523), methotrexate from MCE (USA; Cat. No. HY-14519), and IMQ cream) from Sichuan Mingxin Pharmaceutical (Sichuan, China; Cat. No. H20030129). To configure the MMF-aluminum ions complex (MMFAL), MMF and AlCl₃ were sequentially added to double-distilled water (ddH 2 O), vortexed for mixing, and then adjusted to a pH of 7.0 with NaOH. The solution was stored at 4 °C.
Cell culture
HaCaT cells were cultured in high-glucose DMEM (Biosharp, Anhui, China) containing 10 % fetal bovine serum (MCE, USA), supplemented with 1 % penicillin-streptomycin (Gibco, USA). Cells were maintained at 37 °C in a humidified 5 % CO 2 incubator.
Animal models
Balb/C mice used in this study were purchased from the Laboratory Animal Center of Chongqing Medical University (Chongqing, China) and maintained in a standard pathogen-free (SPF) facility. For the IMQ-induced psoriasis model, 7–8-week-old female Balb/C mice were shaved and depilated on the dorsal surface.
The first experiments: 1. Control group (Control): 50 mg vaseline cream was applied to the exposed area of the back of mice every day, and 1 mL normal saline was injected intraperitoneally (i.p) at Days 0, 3, and 6. 2. Model group (IMQ): A 50 mg dose of IMQ cream was administered daily to the exposed dorsal region of the mice, while 1 mL of normal saline was intraperitoneally injected at Days 0, 3, and 6. 3. Monomethyl fumarate (MMF): A 50 mg dose of IMQ cream was applied to the exposed area of the back of mice every day, and 1 mL 5 mM MMF was injected i.p at Days 0, 3, and 6. 4. Aluminum ion group (Al3+): A 50 mg dose of IMQ cream was applied to the exposed area of the back every day, and 1 mL 5 mM aluminum salt was injected i.p at Days 0, 3, and 6. 5. MMF and aluminum ions combination (MMFAL): A 50 mg dose of IMQ cream was applied to the exposed area of the back of mice every day, and 1 mL 5 mM MMFAL was injected i.p at Days 0, 3, and 6.
The second experiment: 1. Control group (Control): 50 mg vaseline cream was applied to the exposed area of the back of mice every day, and 1 mL normal saline was injected i.p at Days 0, 3, and 6. 2. Model group (IMQ): A 50 mg dose of IMQ cream was applied to the exposed area of the back of mice every day, and 1 mL normal saline was injected i.p at Days 0, 3, and 6. 3. MMF and aluminum ions combination (MMFAL): A 50 mg dose of IMQ cream was applied to the exposed area of the back of mice every day, and 1 mL 5 mM MMFAL was injected i.p at Days 0, 3, and 6. 4. ML385 treatment group (ML385+MMFAL): A 50 mg dose of IMQ cream was applied to the exposed area of the back every day, and 1 mL 30 mg/kg ML385 was injected on Day 0, and then 1 mL 5 mM MMFAL was injected i.p at Days 0, 3, and 6. 5. Positive control group (MTX): A 50 mg dose of IMQ cream was applied to the exposed area of the back, and MTX 1 mL 1 mg/kg was injected i.p every day.
Histology and immunostaining
Skin tissue samples were fixed in 4 % paraformaldehyde for 24 h, embedded in paraffin, and sectioned at 5 μm thickness. The sections were stained with hematoxylin and eosin (H&E) following standard protocols and examined using an Olympus microscope (Japan). For immunohistochemistry, the skin sections were deparaffinized in xylene, rehydrated with graded ethanol, and treated with 3 % hydrogen peroxide to block endogenous peroxidase activity. Non-specific binding was blocked with 2 % bovine serum albumin (BSA) for 20 min. The sections were then incubated with rabbit polyclonal antibodies against Ki67, Ly6g, IL-17 and SOD1 (Servicebio, Wuhan, China) at a dilution of 1:100. After washing, the sections were incubated with a horseradish peroxidase-conjugated anti-rabbit secondary antibody for 30 min, washed with PBS, and visualized with diaminobenzidine and hematoxylin counterstain. The mounted sections were photographed under a Nikon light microscope, and the expression of Ki67, Ly6g, IL-17 and SOD1 in immunohistochemical images was quantified using ImageJ software (National Institutes of Health, USA).
Western blot
HaCaT cells and skin tissues were lysed in RIPA buffer containing phenylmethylsulfonyl fluoride (PMSF; 100:1) for total protein extraction. Protein concentrations were measured using a BCA assay kit. Samples were then boiled to denature proteins, cooled to room temperature, and loaded onto 5%–10 % Tris-glycine SDS polyacrylamide gels for electrophoresis (SDS-PAGE), performed at 60–120 V. The resolved proteins were then transferred onto a 0.45 μm polyvinylidene fluoride (PVDF) membrane at 200 mA for 120 min. The membranes were blocked in 5 % skim milk at room temperature for 1 h, followed by sequential incubation with primary and secondary antibodies. The primary antibodies used included a mouse monoclonal anti-GAPDH antibody (GB1100; Servicebio), rabbit monoclonal anti-Nrf2 antibody (80593-1-RR; Proteintech), rabbit monoclonal anti-NF-κB antibody (ab16502; Abcam), and rabbit monoclonal anti-Phospho-NF-κB p65 (Ser536) antibody (#3033; CST). The secondary antibodies were horseradish peroxidase (HRP)-conjugated secondary anti-mouse immunoglobulin G (IgG)and anti-rabbit IgG (Servicebio, China).
Quantitative reverse transcription-quantitative PCR (qRT-PCR) analyses
Total RNA was extracted from skin tissues or cultured cells using Trizol reagent (Cat. No. T9424; Sigma), followed by purification with chloroform and isopropanol. Purified RNA was reverse-transcribed into complementary DNA (cDNA) using the PrimeScript™ RT reagent Kit with gDNA Eraser (RR047A; TaKaRa). Quantitative PCR was conducted using TB Green® Premix Ex Taq™ II FAST qPCR (CN830S; TaKaRa) on a Qtower real-time PCR machine (Bio-Rad, USA). The primers used in this study are listed in Table S1 .
ROS detection
Intracellular ROS levels were assessed using a 2′,7′-dichlorodihydrofluorescein diacetate (DCFH-DA; MCE, USA) staining assay. HaCaT cells were incubated with 10 μM DCFH-DA according to the manufacturer's instructions, and images were captured using an Olympus microscope.
Cell chemotactic test
HaCaT cells were seeded at a density of 4 × 10⁵ cells/well in 6-well plates and incubated overnight for adherence. After drug treatment, the cells were maintained in a 37 °C, 5 % CO 2 incubator for 24 h. The supernatants from each group were collected for chemotaxis assays. Conditioned supernatant from each treatment group was added to the lower chamber of a Transwell plate, and 1 × 10 6 THP-1 cells were introduced into the upper chamber. The THP-1 cells were incubated for 2 h at 37 °C, after which they were labeled with Calcein AM, visualized by fluorescence microscopy, and harvested from the upper chamber for quantification.
Assessment of clinical symptoms
Psoriasiform inflammation severity was assessed in a blinded manner using the Psoriasis Area and Severity Index (PASI), a validated objective scoring system. The cumulative PASI score was based on three parameters: scaling, erythema, and infiltration. Each parameter was graded on a scale of 0–4, representing the absence, mild, moderate, severe, and most severe levels of each symptom, respectively.
Statistical analysis
All data were analyzed using GraphPad Prism 8.0 software and are presented as means ± SD. Statistical significance was assessed using Student's t-test for comparisons between two groups and one-way ANOVA for multiple group comparisons. A p-value of <0.05 was considered indicative of statistical significance. Each experiment was independently repeated three times.
Results
MMFAL improved IMQ-induced psoriasis in mice
A Balb/C mouse model of psoriasis was induced using IMQ to evaluate the therapeutic effects of MMF, aluminum ions, and MMFAL ( Fig. 1 A). After IMQ treatment, the model mice demonstrated characteristic psoriatic symptoms, including scales, erythema, and infiltration on the dorsal skin. Treatment with either MMF or aluminum ions alone alleviated some psoriatic symptoms ( Fig. 1 B). However, MMFAL treatment resulted in more significant improvement compared to either treatment alone ( Fig. 1 B). Histological examination of skin sections revealed that control mice exhibited a thin stratum corneum with no signs of inflammatory infiltration, whereas the IMQ-treated group displayed pathological changes, including thickened scales, erythema, and inflammatory cell infiltration ( Fig. 1 B). While both MMF and aluminum ions ameliorated these pathological features, MMFAL treatment significantly reduced epidermal thickness and inflammatory cell infiltration to a greater extent than the single treatment groups ( Fig. 1 B–G, H). The Psoriasis Area and Severity Index (PASI) scores, assessed for scales, erythema, infiltration, and skin lesions on day 6, were significantly lower in the MMFAL group compared to either individual treatment group ( Fig. 1 C–F). These findings indicate that MMFAL provides a substantial therapeutic benefit in the IMQ-induced psoriasis model. Fig. 1 MMFAL improved imiquimod-induced psoriasis in mice (A) Experimental design schematic: IMQ was applied daily to the dorsal skin of mice for 7 days to induce psoriasis. MMF combined with aluminum ions and related drugs were administered intraperitoneally on days 0, 3, and 6, with skin lesions photographed on days 0, 3, 6, and 8 (n = 4 or 6). (B) Representative images of each group on day 6, with Hematoxylin and Eosin (H&E) staining performed on dorsal skin tissues from the control, model, and experimental groups. (C) Quantification of epidermal thickness based on H&E staining. (D) Quantification of inflammatory cell infiltration, with the dashed box area representing 0.01 mm 2 . (E–H) Bar graphs illustrating the quantified Psoriasis Area and Severity Index (PASI) scores on day 6. ∗p < 0.05, ∗∗p < 0.01. Fig. 1
MMFAL showed significant anti-inflammatory and antioxidant effects
To further investigate the therapeutic potential of MMFAL in psoriasis, immunohistochemistry (IHC) was conducted to assess Ki67, Ly6G, and IL-17 expression, which are markers of cell proliferation, granulocyte infiltration and inflammation, respectively. IHC results indicated that MMFAL treatment significantly suppressed the expression of Ki67, Ly6G, and IL-17 compared to MMF or aluminum ions treatment alone ( Fig. 2 A–C; H). These findings suggest that MMFAL effectively reduces cell proliferation, diminishes granulocyte infiltration, and decreases IL-17 expression. Western blot (WB) analysis revealed that MMFAL treatment upregulated Nrf2 protein expression in skin lesions ( Fig. 2 D–E). In addition, MMFAL treatment led to a decrease in MDA levels and an increase in glutathione (GSH) levels relative to either MMF or aluminum ions treatments alone ( Fig. 2 F–G). Gene expression analysis showed that IMQ treatment significantly elevated Th1 pro-inflammatory cytokines (IL-1β, TNF-α, and IL-17A) and reduced Th2 anti-inflammatory cytokines (IL-4 and IL-10) in psoriasis model mice ( Fig. 2 I–M). In contrast, MMFAL treatment more effectively suppressed Th1 cytokine expression and enhanced Th2 cytokine expression compared to either MMF or aluminum ions alone ( Fig. 2 I–M). These results suggest that MMFAL activates Nrf2 to counteract oxidative stress and restores Th1/Th2 balance, highlighting its therapeutic potential in psoriasis. Fig. 2 Detection of anti-inflammatory and antioxidant effects of MMFAL (A)Immunohistochemistry (IHC) images of psoriatic skin showing dark brown areas quantified with ImageJ for markers Ki67 (B), Ly6G (C), and IL-17 (H). Scale bar = 50 μm. (D–E) Nrf2 expression in skin lesions analyzed by Western blot. (F–G) Levels of MDA (F) and GSH (G) in skin lesion proteins measured using specific kits. (I–M) qPCR analysis of cytokine expression in psoriatic skin: IL-1β (I), TNF-α (J), IL-17A (K), IL-4 (L), and IL-10 (M). ∗p < 0.05, ∗∗p < 0.01. Fig. 2
MMFAL alleviated TNF-α-induced inflammation status in HaCaT cells
The effect of MMF on HaCaT cell viability was assessed at various concentrations, and since significant cell death was observed at 800 μM, a concentration of 400 μM MMF was selected for subsequent experiments ( Fig. 3 A–B). To establish an inflammatory model, HaCaT cells were treated with 20 ng/ml TNF-α, and subsequently, different combinations of MMF with metal ions (Al³⁺, Mg 2 ⁺, Ca 2 ⁺, Mn 2 ⁺, and Zn 2 ⁺) were applied to the inflamed cells. Expression levels of IL-6, IL-10, and NQO1 were then measured using quantitative PCR (qPCR). The results indicated that MMFAL treatment significantly reduced IL-6 expression while increasing the levels of IL-10 and NQO1 ( Fig. 3 C–E). Fig. 3 MMFAL alleviated TNF-α-induced inflammation in HaCat cells (A- B) CCK-8 assay results showing the effects of MMF (A) and aluminum ions (B) on HaCaT cell viability. (C–E) mRNA expression levels of IL-6 (C), IL-10 (D), and NQO1 (E) detected by qPCR following treatment with MMF combined with salts of aluminum, calcium, magnesium, and manganese. (F–J) mRNA expression levels of inflammatory and anti-inflammatory markers IL-6 (F), TNF-α (G), IL-1β (H), IL-10 (I), and IL-4 (J) assessed by qPCR after MMFAL exposure. (K) Principal component analysis (PCA) conducted on groups following transcriptome sequencing. (L) Differentially expressed genes between the MMFAL and model groups illustrated by a volcano plot. Up: GCLM, GCLC, NQO1, SLC7A11, HMOX1, NQO2 and SQSTM. Down: CXCL10, CXCL11, IL36G, CCL2, IKBKGP1, CCL5, IL-16, IL-6, TNFSF13B, CXCL5 and CCL20. (M) Reactome pathway analysis of differentially expressed genes. ∗p < 0.05, ∗∗p < 0.01. Fig. 3
To further elucidate MMFAL's effects on inflammation in HaCaT cells, controls comprising single treatments with either MMF or aluminum ions were included. We examined the gene expression levels of Th1 cytokines (IL-6, TNF-α, and IL-1β) and Th2 cytokines (IL-4 and IL-10). As anticipated, TNF-α stimulation led to an upregulation of Th1 cytokines IL-6, TNF-α, and IL-1β and a downregulation of Th2 cytokines IL-4 and IL-10 ( Fig. 3 F–I). MMF treatment effectively reduced Th1 cytokine expression, while aluminum ions enhanced Th2 cytokine expression. Notably, only the MMFAL combination simultaneously decreased Th1 cytokines and increased Th2 cytokines, suggesting a unique immunomodulatory effect ( Fig. 3 F–I).
Transcriptomic analysis was conducted to investigate the molecular mechanisms underlying MMFAL's activity in this inflammatory model. Principal component analysis (PCA) demonstrated distinct separation across control, model, MMF, aluminum ions, and MMFAL combination groups, indicating differential gene expression profiles ( Fig. 3 K). The transcriptome data further enabled the construction of a volcano plot, highlighting the differentially expressed genes (DEGs) between the TNF-α model and the MMFAL-treated groups. The key findings included the upregulation of antioxidant genes, such as HO-1 and NQO1, and the downregulation of pro-inflammatory factors and chemokines, including IL-6, CCL2, CCL5, CXCL10, and CXCL11 ( Fig. 3 L). Further analysis of DEGs within the Reactome pathway database revealed significant enrichment of upregulated genes in the Nrf2 antioxidant signaling pathway, suggesting that MMFAL's anti-inflammatory effects may be mediated through this pathway ( Fig. 3 M). These results underscore the potential of MMFAL to mitigate inflammation in HaCaT cells through the activation of Nrf2-driven antioxidant responses.
MMFAL demonstrated enhanced efficacy compared to individual components
Transcriptome sequencing revealed significant upregulation of antioxidant factors HO-1 and NQO1 in the MMFAL treatment group compared to the TNF-α model group ( Fig. 4 A). To investigate the impact of MMFAL on the Nrf2 antioxidant signaling pathway, gene expression levels of Nrf2, HO-1, NQO1, TXNRD1, SRNX1, and GSR were assessed. MMFAL treatment significantly increased HO-1, NQO1, TXNRD1, SRNX1, and GSR gene expression but did not alter Nrf2 gene expression ( Fig. 4 B–G). In contrast, MMFAL reduced MDA levels and elevated GSH levels relative to MMF or aluminum ions treatment alone ( Fig. 4 H–I). Additionally, Western blot analysis showed that both MMF and MMFAL upregulated Nrf2 protein levels( Fig. 4 J). Using the DCFH-DA fluorescent probe, we found that MMFAL also significantly lowered ROS levels compared to either component individually ( Fig. 4 K). Together, these findings indicate that MMFAL activates the Nrf2 signaling pathway, reducing endogenous ROS levels in HaCaT cells. Fig. 4 MMFAL activated the Nrf2 pathway to reduce oxidative stress levels (A) Functional enrichment analysis of differentially expressed genes between the MMFAL and model groups following transcriptome sequencing, highlighting gene enrichment related to the Keap1-Nrf2 signaling pathway. (B–G) mRNA expression levels of Nrf2 (B), HO-1 (C), and NQO1 (D), TXNRD1 (E), SRXN1 (F), and GSR (G) measured by qPCR. (H–I) Levels of MDA (H) and GSH (I) assessed using respective assay kits. (J) Nrf2 protein expression in HaCaT cells analyzed by Western blot. (H) ROS levels detected with the DCFH-DA fluorescent probe. ∗p < 0.05, ∗∗p < 0.01. Fig. 4
The transcriptome sequencing results highlighted the distinct differential expression profiles between MMFAL and its individual components. Relative to MMF, the differentially expressed genes in the MMFAL group were primarily enriched in inflammatory and immune signaling pathways. In contrast, when compared to the aluminum ions group, the differentially expressed genes were predominantly enriched in pathways related to nuclear translocation ( Fig. S1 ). These findings suggest that MMFAL effectively integrates the individual benefits of MMF and aluminum ions, thereby exerting an enhanced anti-inflammatory and antioxidant effect.
MMFAL inhibited the chemotactic activity of HaCaT cells
To elucidate the specific mechanisms by which MMFAL reduces oxidative stress, we examined Nrf2 protein levels in the cytoplasmic and nuclear fractions of HaCaT cells following drug treatment. Results showed that MMFAL induced a greater extent of Nrf2 nuclear translocation than MMF alone, whereas NF-κB nuclear translocation was significantly reduced ( Fig. 5 A–E). Despite no observed changes in total NF-κB protein levels after MMFAL treatment, a notable reduction in NF-κB phosphorylation levels was detected ( Fig. 5 F; G; I). Additionally, we assessed total protein expression and phosphorylation levels of IκB-α, a binding partner of NF-κB. MMFAL treatment did not affect the total IκB-α protein level but led to a marked reduction in its phosphorylation ( Fig. 5 F; H; J). Fig. 5 MMFAL inhibited the chemotactic activity of HaCaT cells (A-E) Western blot analysis of nuclear and cytoplasmic Nrf2 and NF-κB protein expression in HaCaT cells. (F–J) Western blot detection of NF-κB, p-NF-κB, IkB-α and p-IkB-α protein levels in HaCaT cells. (K) Schematic of the Transwell assay setup. (L) Functional enrichment analysis of the chemokine signaling pathway between the MMFAL and model groups following transcriptome sequencing. (M–Q) mRNA expression levels of chemokines CXCL11 (M), and CXCL10 (N), CCL2 (O), CCL20 (P), and CXCL5 (Q) assessed by qPCR. (R) Fluorescence imaging of Calcein AM-labeled THP-1 cells in the upper Transwell chamber. (S) Quantification of THP-1 cell migration to the upper chamber. ∗p < 0.05, ∗∗p < 0.01. Fig. 5
Transcriptome sequencing revealed that chemokines such as CCL2, CCL20, CCL5, CXCL10, and CXCL11 were significantly downregulated in the MMFAL group compared to the model group ( Fig. 5 L). Verification of chemokine expression levels using qPCR corroborated the RNA sequencing findings, with CXCL11 displaying notably higher expression relative to other chemokines ( Fig. 5 M–Q). To assess the functional impact of MMFAL on cell chemotaxis, we performed a transwell assay evaluating HaCaT cell migration toward THP-1 cells, and the results demonstrated that MMFAL significantly reduced the chemotactic activity of HaCaT cells toward THP-1 cells, with a greater effect than either MMF or aluminum ions alone ( Fig. 5 K; R; S). Collectively, these findings suggest that MMFAL modulates the Nrf2/NF-κB signaling pathway, thereby inhibiting the chemotactic response in HaCaT cells.
The Nrf2 inhibitor ML385 reversed the effects of MMFAL on the HaCaT cell model
To investigate the role of Nrf2 in MMFAL's modulation of the NF-κB pathway through Nrf2 nuclear translocation, ML385, a specific Nrf2 inhibitor, was co-administered with MMFAL in HaCaT cells. WB analysis revealed that ML385 reversed MMFAL-induced reductions in NF-κB nuclear translocation and NF-κB phosphorylation in HaCaT cells ( Fig. 6 A–B). Further, we assessed gene expression levels of antioxidant markers (HO-1 and NQO1), cytokines (IL-6 and IL-4), and chemokines (CXCL11 and CCL20) using qPCR following combined ML385 and MMFAL treatment. Consistent with WB results, qPCR confirmed that ML385 counteracted MMFAL's effects on these gene expressions ( Fig. 6 C–H). Finally, a transwell assay was used to examine HaCaT cell chemotaxis toward THP-1 cells following MMFAL and ML385 treatment. Results demonstrated that ML385 reversed MMFAL's inhibitory effect on chemotaxis ( Fig. 6 I–J). These findings indicate that MMFAL's anti-inflammatory and antioxidant therapeutic effects in HaCaT cells are primarily mediated through the Nrf2 pathway, and Nrf2 inhibition may intensify cellular inflammation. Fig. 6 The Nrf2 inhibitor ML385 reversed the effects of MMFAL on HaCaT cells (A) Western blot analysis of nuclear and cytoplasmic Nrf2 and NF-κB protein expression in HaCaT cells treated with ML385. (B) Protein expression levels of Nrf2, NF-κB, and phosphorylated NF-κB (p-NF-κB) in HaCaT cells following ML385 treatment, assessed by Western blot. (C–H) mRNA expression levels of NQO1 (C), HO-1 (D), IL-6 (G), IL-4 (H), CXCL11 (E), and CCL20 (F) measured by qPCR. (I) Fluorescence imaging of Calcein AM-labeled THP-1 cells in the upper Transwell chamber. (J) Quantification of THP-1 cells in the upper chamber of the Transwell assay. ∗p < 0.05, ∗∗p < 0.01. Fig. 6
MMFAL exerts anti-inflammatory and antioxidant effects in psoriasis through Nrf2 regulation in vivo
To further investigate how MMFAL modulates anti-inflammatory and antioxidant responses via Nrf2 in the treatment of psoriasis, we used the Nrf2 inhibitor ML385 during MMFAL administration in a psoriasis mouse model to elucidate Nrf2's role. Methotrexate (MTX), a standard first-line therapeutic agent for psoriasis, was included as a positive control ( Fig. 7 A). PASI scoring was initially conducted on the lesional areas on the backs of mice. The findings demonstrated that MMFAL significantly reduced PASI scores elevated by IMQ, showing an effect comparable to MTX, while this effect was reversed by ML385. Further investigations using H&E staining provided similar results ( Fig. 7 F–H-J). IHC analysis also revealed that expression levels of Ki67, Ly6G, and SOD1 in the MMFAL group were similar to those observed in the MTX group and significantly lower than in the IMQ group ( Fig. 7 B–E). The addition of ML385 alongside MMFAL markedly suppressed these expression levels. Next, we assessed Nrf2 levels in lesional tissues. Western blot analysis indicated that IMQ treatment reduced Nrf2 expression in the skin, while both MMF and MTX activated Nrf2. However, ML385 reversed the Nrf2 activation induced by MMF ( Fig. 7 G–K-M). Additionally, qPCR was used to measure expression levels of Th1 cytokines (IFN-γ, IL-1β, IL-6) and Th2 cytokines (IL-4, IL-10). Results showed that MMFAL treatment decreased Th1 cytokines and increased Th2 cytokines, mirroring the effects observed with MTX ( Fig. 7 N–R). Administration of ML385, however, counteracted the effects of MMFAL. Overall, MMFAL demonstrated efficacy comparable to MTX, though the therapeutic effect of MMFAL was significantly diminished when Nrf2 was inhibited by ML385. Lastly, serum samples were collected from 12 patients with plaque psoriasis and 8 healthy individuals to measure chemokines (CCL20 and CXCL11) and inflammatory factors (IL-6) using ELISA kits ( Fig. 7 S–U). The levels of these markers were significantly elevated in psoriasis patients compared to healthy individuals, consistent with the above results and supporting MMFAL's potential for future clinical use (see Fig. 8 ). Fig. 7 MMFAL modulates psoriasis via Nrf2-mediated anti-inflammatory and antioxidant mechanisms in vivo (A) Experimental design schematic: IMQ was applied daily to the dorsal skin of mice for 7 days to induce psoriasis. MMFAL was administered subcutaneously on days 0, 3, and 6, while ML385 was injected at 30 mg/kg on day 0 and MTX at 1 mg/kg daily (n = 6). (B–E) IHC images of psoriatic skin showing dark brown areas quantified with ImageJ for markers Ki67 (C), Ly6G (D), and SOD1 (E). Scale bar = 50 μm (F) Representative images of the mouse back, H&E staining (20X). (G) Western blot analysis of Nrf2, NF-κB, and phosphorylated NF-κB (p-NF-κB) protein levels in skin lesions. (N) Bar graph showing quantified Psoriasis Area and Severity Index (PASI) scores. (H–I) Quantification of epidermal thickness (H) and inflammatory cell infiltration (I) based on H&E staining. (J–L) Gray value analysis of Nrf2 (J), p-NF-κB (K), and NF-κB (L) protein levels in HaCaT cells. (M–R) mRNA expression levels of cytokines IFN-γ (M), IL-1β (O), IL-6 (P), IL-4 (Q), and IL-10 (R) measured by qPCR. (S–U) Human serum levels of CCL20 (S), CXCL11 (T), and IL-6 (P) detected using ELISA kits. ∗p < 0.05, ∗∗p < 0.01. Fig. 7 Fig. 8 Schematic representation of MMFAL in ameliorating psoriasis by inhibiting inflammation and oxidative stress via the Nrf2/NF-κB signaling pathway. Fig. 8
Discussion
Oxidative stress and inflammation are recognized as key drivers in the development of many chronic diseases, leading to substantial interest in drugs targeting these therapeutic mechanisms [ 21 ]. Nrf2 is a key transcription factor in the occurrence and development of inflammatory diseases. In the early stage of diseases, when tissues are infected or damaged by harmful stimuli (such as pathogens, injuries or irritants), it will lead to the activation of Nrf2 to resist the adverse reactions of the body [ 22 ]. However, with the excessive increase of ROS in the body, the endogenous activation of Nrf2 is destroyed, which leads to the inability of the body to resist various harmful stimuli and the complete outbreak of disease. Therefore, the search for appropriate exogenous Nrf2 activators has become an important means for the treatment of inflammatory diseases [ 23 ]. An article published in the journal redox biology in April this year described that inflammatory diseases pose serious health challenges due to their widespread prevalence and severe impact on the lives of patients, and the activation of Nrf2 for targeted therapy represents a promising means to reduce the burden of these diseases [ 24 ]. An increased focus has been placed on Nrf2 activators due to their antioxidant and anti-inflammatory properties, with both clinical and non-clinical studies exploring their pharmacological potential in treating inflammatory diseases and supporting the feasibility of patented drugs [ 25 ]. The FDA has approved two Nrf2 activators: Omaveloxolone and DMF [ 26 ]. Omaveloxolone, used to treat Friedreich's ataxia, has been found to restore mitochondrial function, reduce oxidative stress, and inhibit proinflammatory signaling. Fumarate esters (FAEs), particularly DMF and its active MMF, have shown promise in autoimmune disease therapy [ 27 ]. DMF and MMF, which are approved by the FDA for the treatment of multiple sclerosis, have demonstrated good clinical efficacy and a broad spectrum of biological activities in psoriasis treatment as well [ 28 ]. Building on these approved therapies, our study further optimizes these compounds, aiming to provide an innovative approach to psoriasis treatment.
Metal elements and metalloproteins are essential to numerous biological processes, including material storage and transport, energy conversion and transfer, signal transduction, and molecular synthesis and degradation [ 29 ]. They also play a role in immune system regulation, with dysregulation often leading to disease [ [30] , [31] , [32] ]. Given that psoriasis involves a characteristic Th1/Th2 immune imbalance, combining MMF with metal ions offers a potential therapeutic strategy. In our study, metal cations, including zinc, manganese, magnesium, calcium and aluminum, were combined with MMF to evaluate their effects in the HaCaT inflammatory cell model. Zn 2 ⁺ proved highly toxic, killing all cells, while Mn 2 ⁺, Mg 2 ⁺ and Ca 2 ⁺ were less effective compared to Al³⁺. Consequently, we selected the MMFAL combination for further experiments. Aluminum ions, commonly used as vaccine adjuvants, enhance antigen immunogenicity by stimulating type 2 immune responses [ 33 ]. Theoretically, aluminum ions may contribute therapeutic effects in psoriasis by modulating the Th1/Th2 balance. In both a psoriasis mouse model and the inflammatory HaCaT cell model, we confirmed that aluminum ions promoted Th2-type cytokine expression in skin lesions and HaCaT cells, effectively inhibiting psoriasis-like inflammation. Notably, the MMFAL combination demonstrated superior efficacy compared to aluminum ions alone.
A recent study found that MMF's therapeutic effect in psoriasis primarily depends on its antioxidant properties [ 34 ]. Furthermore, prior research has established oxidative stress as a significant factor in the pathogenesis of psoriasis [ 35 ]. Specifically, psoriasis development is influenced by an imbalance between oxidants and antioxidants, characterized by increased ROS production and reduced antioxidant enzyme activity [ 35 ]. Biomarkers of oxidative stress have shown utility in assessing psoriasis severity and predicting treatment outcomes and complications [ 36 ]. Additionally, psoriatic symptoms can be exacerbated by various external pro-oxidative stressors, including anesthetics, tobacco use, alcohol consumption, psychological stress, and bacterial infections [ 37 ]. In our study, we demonstrated that combining MMF with aluminum ions was more effective in alleviating IMQ-induced psoriasis symptoms in a mouse model and in mitigating TNF-α-induced inflammation in the HaCaT cell model, compared to either MMF or aluminum ions alone.
To further elucidate the molecular mechanisms underlying MMFAL's effects, we conducted transcriptome sequencing to identify potential targets in the HaCaT inflammatory cell model. Enrichment analysis revealed that the Keap1/Nrf2 pathway plays a central role. The Keap1/Nrf2 pathway is known for its antioxidant and anti-inflammatory properties and is important for maintaining skin homeostasis [ 38 ]. Previous studies have shown that Nrf2 promotes epidermal barrier formation and enhances keratinocyte differentiation, which are essential processes in skin health [ 39 , 40 ]. Psoriasis is an inflammatory disease. It has been reported that the expression of Nrf2 is decreased in patients with psoriasis and in IMQ-induced psoriasis mouse models. The antioxidant sulforaphane can activate Nrf2 to play a therapeutic role in psoriasis [ 41 ]. In our psoriasis mouse model, we observed a significant reduction in Nrf2 expression in lesional skin induced by IMQ. Treatment with MMFAL significantly restored Nrf2 expression and alleviated pathological psoriasis symptoms. Similarly, TNF-α stimulation reduced Nrf2 expression in HaCaT cells in vitro, while MMFAL treatment effectively restored Nrf2 expression and reduced TNF-α-induced ROS production.
Another key mechanism by which MMFAL provides immune protection against psoriasis is through the inhibition of the NF-κB pathway. NF-κB is recognized as a major inflammatory pathway implicated in the pathogenesis and progression of psoriasis [ 42 ]. Inhibitors targeting NF-κB, such as etanercept, infliximab and adalimumab, have shown effectiveness in clinical psoriasis treatment [ [43] , [44] , [45] ]. In our study, TNF-α-stimulated HaCaT cells were treated with MMFAL, followed by an examination of NF-κB pathway activation. The results indicated that MMFAL significantly reduced both nuclear translocation and phosphorylation of NF-κB in this model. A hallmark of psoriasis is the secretion of large quantities of chemokines by keratinocytes, which induces the chemotaxis of monocytes from dermal tissue into the epidermis, thereby intensifying skin inflammation. Our transcriptome sequencing results supported this, revealing that MMFAL significantly down-regulated chemokine expression in HaCaT cells. To evaluate MMFAL's effect on chemotaxis, we assessed chemokine activity in HaCaT cells, identifying CXCL11 as a central factor in this process. Additionally, MMFAL treatment was shown to reverse inflammatory cytokine expression, providing further confirmation that the NF-κB pathway is directly regulated by Nrf2.
Conclusion
The findings of this study highlight the enhanced therapeutic potential of a novel combination of the licensed drug MMF and aluminum ions in alleviating psoriasis, as demonstrated in both an IMQ-induced mouse model and TNF-α-stimulated HaCaT cells. This combination treatment not only significantly improved observable symptoms and histological features but also exhibited strong anti-inflammatory and antioxidant effects mediated through activation of the Nrf2 pathway. By effectively modulating the Th1/Th2 cytokine balance and inhibiting key inflammatory pathways, including NF-κB, the MMF-aluminum complex, built from a drug molecule with an established safety profile, demonstrated superior efficacy compared to individual components. These findings highlight the potential clinical application of this MMF-aluminum complex in managing psoriasis and support further research into its mechanisms and broader therapeutic potential in autoimmune disorders.
CRediT authorship contribution statement
Hang Han: Writing – original draft, Methodology, Investigation, Formal analysis. Guojiang Zhang: Supervision, Investigation, Formal analysis. Yuanyuan Yang: Visualization, Formal analysis. Chenxi Li: Investigation. Xiandeng Li: Investigation. Ling Zhong: Validation. Zan Chen: Supervision. Jianxia Xiong: Validation. Tao Cai: Supervision. Lingjuan Zhang: Validation. Xiao Zhang: Project administration, Funding acquisition. Qinjian Zhao: Supervision, Project administration, Funding acquisition, Conceptualization.
Ethical approval
The clinical serum samples used in this study were collected from patients with written informed consent, and the study protocol was approved by the Ethics Committee of Chongqing Medical University (Approval No. 2024129).
All animal procedures performed in this project were approved by the Institutional Animal Care and Use Committee of Chongqing Medical University (protocol code IACUC-CQMU-20240582, approval date: July 30, 2024).
MMFAL activates Nrf2 nuclear translocation in keratinocytes, which in turn regulates the expression of antioxidant enzymes, including HO-1, NQO1, and GSH. Concurrently, Nrf2 nuclear translocation inhibits the nuclear translocation and phosphorylation of NF-κB, leading to a decrease in NF-κB-regulated Th1 cytokines (IL-6, TNF-α, and IL-1β), an increase in Th2 cytokines (IL-10 and IL-4), and a reduction in chemokines, particularly CXCL11. Through these mechanisms, MMFAL exerts anti-inflammatory and antioxidant effects, contributing to its therapeutic efficacy in a psoriasis mouse model. Table S1Primer sequences for cytokine detection Gene names Primer sequences GAPDH primers F 5′-GGAGCGAGATCCCTCCAAAAT-3′ primers R 5′-GGCTGTTGTCATACTTCTCATGG-3′ IL-6 primers F 5′-ACTCACCTCTTCAGAACGAATTG-3′ primers R 5′-CCATCTTTGGAAGGTTCAGGTTG-3′ IL-17A primers F 5′-GCCTTCAAGACTGAACACCG-3′ primers R 5′-TGACATGCCATTCCTCAGGG-3′ IL-1β primers F 5′-ATGATGGCTTATTACAGTGGCAA-3′ primers R 5′-GTCGGAGATTCGTAGCTGGA-3′ TNF-α primers F 5′-CCTCTCTCTAATCAGCCCTCTG-3′ primers R 5′-GAGGACCTGGGAGTAGATGAG-3′ IL-10 primers F 5′-GCTGGAGGACTTTAAGGGTTAC-3′ primers R 5′-GATGTCTGGGTCTTGGTTCTC-3′ IL-4 primers F 5′-CCAACTGCTTCCCCCTCTG-3′ primers R 5′-TCTGTTACGGTCAACTCGGTG-3′ HO-1 primers F 5′-AAGACTGCGTTCCTGCTCAAC-3′ primers R 5′-AAAGCCCTACAGCAACTGTCG-3′ NQO1 primers F 5′-GAAGAGCACTGATCGTACTGGC-3′ primers R 5′-GGATACTGAAAGTTCGCAGGG-3′ Nrf2 primers F 5′-ATTGCCTGTAAGTCCTGGTCA-3′ primers R 5′-ACTGCTCTTTGGACATCATTTCG-3′ CCL2 primers F 5′-CAGCCAGATGCAATCAATGCC-3′ primers R 5′-TGGAATCCTGAACCCACTTCT-3′ CXCL5 primers F 5′-AGCTGCGTTGCGTTTGTTTAC-3′ primers R 5′-TGGCGAACACTTGCAGATTAC-3′ CXCL10 primers F 5′-GTGGCATTCAAGGAGTACCTC-3′ primers R 5′-TGATGGCCTTCGATTCTGGATT-3′ CXCL11 primers F 5′-GACGCTGTCTTTGCATAGGC-3′ primers R 5′-GGATTTAGGCATCGTTGTCCTTT-3′ CCL20 primers F 5′-TGCTGTACCAAGAGTTTGCTC-3′ primers R 5′-CGCACACAGACAACTTTTTCTTT-3′ IFN-γ primers F 5′-TCGGTAACTGACTTGAATGTCCA-3′ primers R 5′-TCGCTTCCCTGTTTTAGCTGC-3′ TXNRD1 primers F 5′-ATATGGCAAGAAGGTGATGGTCC-3′ primers R 5′-GGGCTTGTCCTAACAAAGCTG-3′ SRXN1 primers F 5′-CAGGGAGGTGACTACTTCTACTC-3′ primers R 5′-CAGGTACACCCTTAGGTCTGA-3′ GSR primers F 5′-CACTTGCGTGAATGTTGGATG-3′ primers R 5′-TGGGATCACTCGTGAAGGCT-3′
Table S1Primer sequences for cytokine detection
| Gene names | Primer sequences | |
| GAPDH | primers F | 5′-GGAGCGAGATCCCTCCAAAAT-3′ |
| primers R | 5′-GGCTGTTGTCATACTTCTCATGG-3′ | |
| IL-6 | primers F | 5′-ACTCACCTCTTCAGAACGAATTG-3′ |
| primers R | 5′-CCATCTTTGGAAGGTTCAGGTTG-3′ | |
| IL-17A | primers F | 5′-GCCTTCAAGACTGAACACCG-3′ |
| primers R | 5′-TGACATGCCATTCCTCAGGG-3′ | |
| IL-1β | primers F | 5′-ATGATGGCTTATTACAGTGGCAA-3′ |
| primers R | 5′-GTCGGAGATTCGTAGCTGGA-3′ | |
| TNF-α | primers F | 5′-CCTCTCTCTAATCAGCCCTCTG-3′ |
| primers R | 5′-GAGGACCTGGGAGTAGATGAG-3′ | |
| IL-10 | primers F | 5′-GCTGGAGGACTTTAAGGGTTAC-3′ |
| primers R | 5′-GATGTCTGGGTCTTGGTTCTC-3′ | |
| IL-4 | primers F | 5′-CCAACTGCTTCCCCCTCTG-3′ |
| primers R | 5′-TCTGTTACGGTCAACTCGGTG-3′ | |
| HO-1 | primers F | 5′-AAGACTGCGTTCCTGCTCAAC-3′ |
| primers R | 5′-AAAGCCCTACAGCAACTGTCG-3′ | |
| NQO1 | primers F | 5′-GAAGAGCACTGATCGTACTGGC-3′ |
| primers R | 5′-GGATACTGAAAGTTCGCAGGG-3′ | |
| Nrf2 | primers F | 5′-ATTGCCTGTAAGTCCTGGTCA-3′ |
| primers R | 5′-ACTGCTCTTTGGACATCATTTCG-3′ | |
| CCL2 | primers F | 5′-CAGCCAGATGCAATCAATGCC-3′ |
| primers R | 5′-TGGAATCCTGAACCCACTTCT-3′ | |
| CXCL5 | primers F | 5′-AGCTGCGTTGCGTTTGTTTAC-3′ |
| primers R | 5′-TGGCGAACACTTGCAGATTAC-3′ | |
| CXCL10 | primers F | 5′-GTGGCATTCAAGGAGTACCTC-3′ |
| primers R | 5′-TGATGGCCTTCGATTCTGGATT-3′ | |
| CXCL11 | primers F | 5′-GACGCTGTCTTTGCATAGGC-3′ |
| primers R | 5′-GGATTTAGGCATCGTTGTCCTTT-3′ | |
| CCL20 | primers F | 5′-TGCTGTACCAAGAGTTTGCTC-3′ |
| primers R | 5′-CGCACACAGACAACTTTTTCTTT-3′ | |
| IFN-γ | primers F | 5′-TCGGTAACTGACTTGAATGTCCA-3′ |
| primers R | 5′-TCGCTTCCCTGTTTTAGCTGC-3′ | |
| TXNRD1 | primers F | 5′-ATATGGCAAGAAGGTGATGGTCC-3′ |
| primers R | 5′-GGGCTTGTCCTAACAAAGCTG-3′ | |
| SRXN1 | primers F | 5′-CAGGGAGGTGACTACTTCTACTC-3′ |
| primers R | 5′-CAGGTACACCCTTAGGTCTGA-3′ | |
| GSR | primers F | 5′-CACTTGCGTGAATGTTGGATG-3′ |
| primers R | 5′-TGGGATCACTCGTGAAGGCT-3′ |
Funding
This work was supported by grants from the 10.13039/501100001809 National Natural Science Foundation of China ( 32070925 to Qinjian Zhao and 82371832 to Xiao Zhang), 10.13039/501100005230 Natural Science Foundation of Chongqing City ( 2023NSCQ-MSX1536 to Xiao Zhang), 10.13039/501100003392 Natural Science Foundation of Fujian Province ( 2023J011235 to Xiao Zhang), Chongqing Education Commission of Science and Technology Research Project ( KJQN202300453 to Xiao Zhang), Natura Science Foundation of Beijing City ( L242117 to Xiao Zhang), Chongqing Technology Education Commission Science and Research Project ( KJZD-M202400401 to Xiao Zhang).
Declaration of competing interest
The authors declare that they have no known competing financial interests or personal relationships.
References
1 A. D, N. B, D. M A H. A. W. POS1607 biologics therapies for psoriasis decrease future risk for developing psoriatic arthritis Ann. Rheum. Dis. 82 Suppl 1 2023 1148
2 Wang X.Y. Zhang C.L. Wang W.H. Time to relapse after treatment withdrawal for different biologics used to treat plaque psoriasis Chinese Med. J. Peking 133 24 2020 2998 3000 10.1097/CM9.0000000000001232 PMC7752671 33337760
3 Wronski A. Wojcik P. Impact of ROS-dependent lipid metabolism on psoriasis pathophysiology Int. J. Mol. Sci. 23 20 2022 10.3390/ijms232012137 PMC9602909 36292991
4 Plenkowska J. Gabig-Ciminska M. Mozolewski P. Oxidative stress as an important contributor to the pathogenesis of psoriasis Int. J. Mol. Sci. 21 17 2020 10.3390/ijms21176206 PMC7503883 32867343
5 Li Y. Paonessa J.D. Zhang Y. Mechanism of chemical activation of Nrf2 PLoS One 7 4 2012 e35122 10.1371/journal.pone.0035122 PMC3338841 22558124
6 Cuadrado A. Rojo A.I. Wells G. Hayes J.D. Cousin S.P. Rumsey W.L. Attucks O.C. Franklin S. Levonen A.L. Kensler T.W. Dinkova-Kostova A.T. Therapeutic targeting of the NRF2 and KEAP1 partnership in chronic diseases Nat. Rev. Drug Discov. 18 4 2019 295 317 30610225 10.1038/s41573-018-0008-x
7 Ogawa T. Ishitsuka Y. The role of KEAP1-NRF2 system in atopic dermatitis and psoriasis Antioxidants-Basel 11 7 2022 10.3390/antiox11071397 PMC9312147 35883888
8 Olagnier D. Farahani E. Thyrsted J. Blay-Cadanet J. Herengt A. Idorn M. Hait A. Hernaez B. Knudsen A. Iversen M.B. Schilling M. Jorgensen S.E. Thomsen M. Reinert L.S. Lappe M. Hoang H.D. Gilchrist V.H. Hansen A.L. Ottosen R. Nielsen C.G. Moller C. van der Horst D. Peri S. Balachandran S. Huang J. Jakobsen M. Svenningsen E.B. Poulsen T.B. Bartsch L. Thielke A.L. Luo Y. Alain T. Rehwinkel J. Alcami A. Hiscott J. Mogensen T.H. Paludan S.R. Holm C.K. SARS-CoV2-mediated suppression of NRF2-signaling reveals potent antiviral and anti-inflammatory activity of 4-octyl-itaconate and dimethyl fumarate Nat. Commun. 11 1 2020 4938 33009401 10.1038/s41467-020-18764-3 PMC7532469
9 Profeta V. McIntyre K. Wells M. Park C. Lynch D.R. Omaveloxolone: an activator of Nrf2 for the treatment of Friedreich ataxia Expet Opin. Invest. Drugs 32 1 2023 5 16 10.1080/13543784.2023.2173063 36708320
10 Lategan T.W. Wang L. Sprague T.N. Rousseau F.S. Pharmacokinetics and bioavailability of monomethyl fumarate following a single oral dose of bafiertam (monomethyl fumarate) or tecfidera((R)) (dimethyl fumarate) CNS Drugs 35 5 2021 567 574 33797063 10.1007/s40263-021-00799-9 PMC8144082
11 Morrison P.J. Suhrkamp I. Gerdes S. Mrowietz U. Oral dimethyl fumarate induces changes within the peripheral neutrophil compartment of patients with psoriasis that are linked with skin improvement Brit. J. Dermatol. 185 3 2021 605 615 33657656 10.1111/bjd.19899
12 Linker R.A. Lee D.H. Ryan S. van Dam A.M. Conrad R. Bista P. Zeng W. Hronowsky X. Buko A. Chollate S. Ellrichmann G. Bruck W. Dawson K. Goelz S. Wiese S. Scannevin R.H. Lukashev M. Gold R. Fumaric acid esters exert neuroprotective effects in neuroinflammation via activation of the Nrf2 antioxidant pathway Brain 134 Pt 3 2011 678 692 21354971 10.1093/brain/awq386
13 Liou Y.H. Personnaz J. Jacobi D. Knudsen N.H. Chalom M.M. Starost K.A. Nnah I.C. Lee C.H. Hepatic Fis1 regulates mitochondrial integrated stress response and improves metabolic homeostasis JCI Insight 7 4 2022 10.1172/jci.insight.150041 PMC8876406 35015731
14 Yao Y. Miao W. Liu Z. Han W. Shi K. Shen Y. Li H. Liu Q. Fu Y. Huang D. Shi F.D. Dimethyl fumarate and monomethyl fumarate promote post-ischemic recovery in mice Transl. Stroke Res. 7 6 2016 535 547 27614618 10.1007/s12975-016-0496-0 PMC5065588
15 Kumar M. Sharma G. Kumar R. Singh B. Katare O.P. Raza K. Lysine-based C(60)-fullerene nanoconjugates for monomethyl fumarate delivery: a novel nanomedicine for brain cancer cells ACS Biomater. Sci. Eng. 4 6 2018 2134 2142 33435037 10.1021/acsbiomaterials.7b01031
16 Herrmann A.K. Wullner V. Moos S. Graf J. Chen J. Kieseier B. Kurschus F.C. Albrecht P. Vangheluwe P. Methner A. Dimethyl fumarate alters intracellular Ca(2+) handling in immune cells by redox-mediated pleiotropic effects Free Radical Bio. Med. 141 2019 338 347 31279969 10.1016/j.freeradbiomed.2019.07.005
17 Lu F. Hogenesch H. Kinetics of the inflammatory response following intramuscular injection of aluminum adjuvant Vaccine 31 37 2013 3979 3986 23770306 10.1016/j.vaccine.2013.05.107
18 Shi S. Zhu H. Xia X. Liang Z. Ma X. Sun B. Vaccine adjuvants: understanding the structure and mechanism of adjuvanticity Vaccine 37 24 2019 3167 3178 31047671 10.1016/j.vaccine.2019.04.055
19 Moyer T.J. Kato Y. Abraham W. Chang J. Kulp D.W. Watson N. Turner H.L. Menis S. Abbott R.K. Bhiman J.N. Melo M.B. Simon H.A. Herrera-De L.M.S. Liang S. Seumois G. Agarwal Y. Li N. Burton D.R. Ward A.B. Schief W.R. Crotty S. Irvine D.J. Engineered immunogen binding to alum adjuvant enhances humoral immunity Nat. Med. 26 3 2020 430 440 32066977 10.1038/s41591-020-0753-3 PMC7069805
20 Liao Y. Sun L. Nie M. Li J. Huang X. Heng S. Zhang W. Xia T. Guo Z. Zhao Q. Zhang L.J. Modulation of skin inflammatory responses by aluminum adjuvant Pharmaceutics 15 2 2023 10.3390/pharmaceutics15020576 PMC9966661 36839900
21 Han H. Zhang G. Zhang X. Zhao Q. Nrf2-mediated ferroptosis inhibition: a novel approach for managing inflammatory diseases Inflammopharmacology 32 5 2024 2961 2986 39126567 10.1007/s10787-024-01519-7
22 Hayes J.D. Dinkova-Kostova A.T. The Nrf2 regulatory network provides an interface between redox and intermediary metabolism Trends Biochem. Sci. 39 4 2014 199 218 24647116 10.1016/j.tibs.2014.02.002
23 Jia H. Zhang Y. Si X. Jin Y. Jiang D. Dai Z. Wu Z. Quercetin alleviates oxidative damage by activating nuclear factor erythroid 2-related factor 2 signaling in porcine enterocytes Nutrients 13 2 2021 10.3390/nu13020375 PMC7911945 33530513
24 Pant T. Uche N. Juric M. Zielonka J. Bai X. Regulation of immunomodulatory networks by Nrf2-activation in immune cells: redox control and therapeutic potential in inflammatory diseases Redox Biol. 70 2024 103077 10.1016/j.redox.2024.103077 PMC10877431 38359749
25 Kim M.J. Jeon J.H. Recent advances in understanding Nrf2 agonism and its potential clinical application to metabolic and inflammatory diseases Int. J. Mol. Sci. 23 5 2022 10.3390/ijms23052846 PMC8910922 35269986
26 Pilotto F. Chellapandi D.M. Puccio H. Omaveloxolone: a groundbreaking milestone as the first FDA-approved drug for Friedreich ataxia Trends Mol. Med. 30 2 2024 117 125 38272714 10.1016/j.molmed.2023.12.002
27 Hoffmann J. Schaekel K. Enk A.H. Hadaschik E.N. Differential effects of dimethyl fumarate and monomethyl fumarate on neutrophil granulocyte and PBMC apoptosis J. Invest. Dermatol. 141 3 2021 699 702 32771469 10.1016/j.jid.2020.06.028
28 Maiti A. Halder A. Dinda S. Pahari G. Ghoshal D. Construction of four new d10 metal ion coordination polymers: synthesis, characterization and structural diversity Polyhedron 227 2022 116144
29 Zhou Y. Li H. Sun H. Metalloproteomics for biomedical research: methodology and applications Annu. Rev. Biochem. 91 2022 449 473 35303792 10.1146/annurev-biochem-040320-104628
30 Mu Q. Chen L. Gao X. Shen S. Sheng W. Min J. Wang F. The role of iron homeostasis in remodeling immune function and regulating inflammatory disease Sci. Bull. 66 17 2021 1806 1816 10.1016/j.scib.2021.02.010 36654387
31 Sadeghsoltani F. Mohammadzadeh I. Safari M.M. Hassanpour P. Izadpanah M. Qujeq D. Moein S. Vaghari-Tabari M. Zinc and respiratory viral infections: important trace element in anti-viral response and immune regulation Biol. Trace Elem. Res. 200 6 2022 2556 2571 34368933 10.1007/s12011-021-02859-z PMC8349606
32 Liu Y. Zhu J. Xu L. Wang B. Lin W. Luo Y. Copper regulation of immune response and potential implications for treating orthopedic disorders Front. Mol. Biosci. 9 2022 1065265 10.3389/fmolb.2022.1065265 PMC9762617 36545506
33 Benson O. Landers J. Janczak K. O'Konek J. Differential induction of trained innate immunity following early-life immunization with aluminum adjuvant results in preferential priming of Th2-biased immune responses J. Allergy Clin. Immun. 149 2 2022 AB153
34 Morrison P.J. Suhrkamp I. Gerdes S. Mrowietz U. Oral dimethyl fumarate induces changes within the peripheral neutrophil compartment of patients with psoriasis that are linked with skin improvement BRIT J DERMATOL 185 3 2021 605 615 33657656 10.1111/bjd.19899
35 Hu J. Bian Q. Ma X. Xu Y. Gao J. A double-edged sword: ROS related therapies in the treatment of psoriasis Asian J. Pharm. Sci. 17 6 2022 798 816 36600897 10.1016/j.ajps.2022.10.005 PMC9800958
36 Dobrică E. Cozma M. Găman M. Voiculescu V. Găman A.M. The involvement of oxidative stress in psoriasis: a systematic review Antioxidants 11 2 2022 282 10.3390/antiox11020282 PMC8868066 35204165
37 Parab S. Doshi G. An update on emerging immunological targets and their inhibitors in the treatment of psoriasis Int. Immunopharmacol. 113 Pt A 2022 109341 10.1016/j.intimp.2022.109341 36327870
38 Ogawa T. Ishitsuka Y. The role of KEAP1-NRF2 system in atopic dermatitis and psoriasis Antioxidants 11 7 2022 1397 10.3390/antiox11071397 PMC9312147 35883888
39 Ogawa T. Ishitsuka Y. Inoue S. Nakamura Y. Saito A. Okiyama N. Fujisawa Y. Furuta J. Watanabe R. Fujimoto M. Nuclear factor erythroid 2-related factor 2 (Nrf2) regulates epidermal keratinization under psoriatic skin inflammation Am. J. Pathol. 190 3 2020 577 585 31953037 10.1016/j.ajpath.2019.10.022
40 Liu G.T. Li Y.L. Wang J. Dong C.Z. Deng M. Tai M. Deng L. Che B. Lin L. Du Z.Y. Chen H.X. Improvement of skin barrier dysfunction by phenolic-containing extracts of lycium barbarum via Nrf2/HO-1 regulation Photochem. Photobiol. 98 1 2022 262 271 34342370 10.1111/php.13498
41 Ma C. Gu C. Lian P. Wazir J. Lu R. Ruan B. Wei L. Li L. Pu W. Peng Z. Wang W. Zong Y. Huang Z. Wang H. Lu Y. Su Z. Sulforaphane alleviates psoriasis by enhancing antioxidant defense through KEAP1-NRF2 Pathway activation and attenuating inflammatory signaling Cell Death Dis. 14 11 2023 768 38007430 10.1038/s41419-023-06234-9 PMC10676357
42 Goldminz A.M. Au S.C. Kim N. Gottlieb A.B. Lizzul P.F. NF-kappaB: an essential transcription factor in psoriasis J. Dermatol. Sci. 69 2 2013 89 94 23219896 10.1016/j.jdermsci.2012.11.002
43 Griffiths C.E. Strober B.E. van de Kerkhof P. Ho V. Fidelus-Gort R. Yeilding N. Guzzo C. Xia Y. Zhou B. Li S. Dooley L.T. Goldstein N.H. Menter A. Comparison of ustekinumab and etanercept for moderate-to-severe psoriasis New Engl. J. Med. 362 2 2010 118 128 20071701 10.1056/NEJMoa0810652
44 Dapavo P. Vujic I. Fierro M.T. Quaglino P. Sanlorenzo M. The infliximab biosimilar in the treatment of moderate to severe plaque psoriasis J. Am. Acad. Dermatol. 75 4 2016 736 739 27473452 10.1016/j.jaad.2016.04.068
45 van der Kraaij G. Busard C. van den Reek J. Menting S. Musters A. Hutten B. de Rie M. Ouwerkerk W. van Bezooijen S.J. Prens E. Rispens T. de Vries A. de Jong E. de Kort W. Lambert J. van Doorn M. Spuls P. Adalimumab with methotrexate vs. Adalimumab monotherapy in psoriasis: first-year results of a single-blind randomized controlled trial J. Invest. Dermatol. 142 9 2022 2375 2383 35276223 10.1016/j.jid.2022.01.033
Supplementary data
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Data availability
Data will be made available on request.
Supplementary data to this article can be found online at https://doi.org/10.1016/j.redox.2024.103482 .