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Biomedicine & Pharmacotherapy =... May 2021Atopic dermatitis (AD) is a chronic inflammatory skin disorder that affects 10-20% of the world's population. Therefore, the discovery of drugs for the treatment of AD...
Atopic dermatitis (AD) is a chronic inflammatory skin disorder that affects 10-20% of the world's population. Therefore, the discovery of drugs for the treatment of AD is important for human health. Hispidulin (HPD; also known as scutellarein 6-methyl ether or dinatin) is a natural flavone that exerts anti-inflammatory effects. In the present study, the effectiveness of HPD on AD-like skin inflammation was investigated. We used a mouse AD model through repeated exposure of mice to 2,4-dinitrochlorobenzene and house dust mite extract (Dermatophagoides farinae extract, DFE) to the ears. In addition, tumor necrosis factor-α and interferon-γ-activated keratinocytes (HaCaT cells) were used to investigate the underlying mechanism of HPD action. Oral administration of HPD alleviated AD-like skin inflammations: it reduced ear thickness; serum immunoglobulin (Ig)E, DFE-specific IgE, and IgG2a levels; and inflammatory cell infiltration. HPD reduced the expression of pro-inflammatory cytokines and chemokines through inhibition of signal transducer and activator of transcription 1 nuclear factor-κB in HaCaT cells. Taken together, these results suggest that HPD could be a potential drug candidate for the treatment of AD.
Topics: Animals; Anti-Allergic Agents; Antigens, Dermatophagoides; Dermatitis, Atopic; Dinitrochlorobenzene; Eosinophils; Female; Flavones; Immunoglobulins; Keratinocytes; Mast Cells; Mice; Mice, Inbred BALB C; Pyroglyphidae; Skin
PubMed: 33761595
DOI: 10.1016/j.biopha.2021.111359 -
Molecular Medicine Reports Dec 2021Atopic dermatitis (AD) is a chronic inflammatory allergic skin disease, characterized by pruritic and eczematous skin lesions. Turcz (LLT) is a perennial herb that has...
Atopic dermatitis (AD) is a chronic inflammatory allergic skin disease, characterized by pruritic and eczematous skin lesions. Turcz (LLT) is a perennial herb that has been reported to have various biological properties, including effects on blood circulation, as well as anti‑inflammatory, antioxidant, anti‑vascular inflammation and wound‑healing effects. However, whether LLT improves dermatitis and the underlying mechanisms has yet to be determined. The aim of the present study was to determine whether LLT can improve 2,4‑dinitrochlorobenzene (DNCB)‑induced dermatitis and to verify the inhibitory effect of LLT on the expression of chemokines and pro‑inflammatory cytokines in the HaCaT immortalized keratinocyte cell line. In addition, the anti‑inflammatory function of LLT in RAW264.7 mouse macrophages was investigated. In the DNCB‑induced AD mouse model, LLT inhibited infiltration by mast cells, eosinophils and CD8 cells in the dorsal skin tissue of AD mice, and suppressed the expression of IgE and IL‑6 in serum. In addition, LLT inhibited the phosphorylation of ERK and JNK, as well as NF‑κB in skin tissue. In the HaCaT cell model induced by TNF‑α/IFN‑γ, LLT inhibited the expression of thymus and activation‑regulated chemokine, granulocyte‑macrophage colony‑stimulating factor, monocyte chemoattractant protein‑1, TNF‑α and IL‑1β, whilst inhibiting the phosphorylation of NF‑κB. In addition, in the lipopolysaccharide‑induced RAW 264.7 cell inflammation model, LLT inhibited the expression of TNF‑α and IFN‑γ, the nuclear translocation of NF‑κB and the phosphorylation of ERK and JNK. These results suggested that LLT may be a promising candidate for the treatment of inflammatory dermatitis.
Topics: Animals; Anti-Inflammatory Agents; Antioxidants; CD8-Positive T-Lymphocytes; Chemokines; Cytokines; Dermatitis, Atopic; Dinitrochlorobenzene; Disease Models, Animal; Eosinophils; HaCaT Cells; Humans; Lycopus; MAP Kinase Kinase 4; MAP Kinase Signaling System; Macrophages; Male; Mast Cells; Medicine, Chinese Traditional; Mice; Mice, Inbred BALB C; Mitogen-Activated Protein Kinases; NF-kappa B; Plant Extracts; Skin; Wound Healing
PubMed: 34581418
DOI: 10.3892/mmr.2021.12467 -
International Journal of Biological... Jan 2024Atopic dermatitis (AD) is usually treated with steroids, but long-term use is not an effective cure because side effects and disease aggravation. Therefore, more...
Atopic dermatitis (AD) is usually treated with steroids, but long-term use is not an effective cure because side effects and disease aggravation. Therefore, more effective and safer treatments are needed. Using dexamethasone as the positive control, the mechanism of action of water-extracted homogeneous honeysuckle Lonicera japonica polysaccharide (WLJP-025p) to alleviate AD was studied. Mice were administered 2,4-dinitrochlorobenzene in their bare back and right ear to mimic an AD model. The efficacy of WLJP-025p in AD was assessed by measuring right ear thickness and skin lesion scores, pathological observation (haematoxylin-eosin and toluidine blue staining), and serum IgE and IL-1β concentrations. The expression of relevant genes and proteins in the serum and back skin was detected using RT-qPCR, ELISA, western blotting, and immunofluorescence. Molecular docking and dynamic simulation of WLJP-025p and Act1 were performed. WLJP-025p considerably alleviated skin hyperplasia and pathological abnormalities in AD mice and inhibited the expression of Act1, Nucleus-P65, Nucleus-AP-1, and MAPK-related proteins in skin tissues. WLJP-025p formed a stable conformation with Act1, inhibited splenic Th17 differentiation, IL-17 release, and upregulated the expression of related skin barrier proteins. In conclusion, WLJP-025p affects the inflammation regulation via the MAPK/NFκB/AP-1 axis by binding to Act1, promotes the recovery of epithelial barrier function, and alleviates AD in mice.
Topics: Animals; Mice; Dermatitis, Atopic; Lonicera; Transcription Factor AP-1; Molecular Docking Simulation; Cytokines; Skin; Polysaccharides; Mice, Inbred BALB C
PubMed: 38016605
DOI: 10.1016/j.ijbiomac.2023.128435 -
International Immunopharmacology Jan 2024Atopic dermatitis (AD) is a chronic, inflammatory cutaneous disease driven by immune dysregulation. Catalpol is an iridoids, possessing anti-inflammatory, antioxidant,...
Atopic dermatitis (AD) is a chronic, inflammatory cutaneous disease driven by immune dysregulation. Catalpol is an iridoids, possessing anti-inflammatory, antioxidant, and neuroprotective activities. It can be added to food as a dietary supplement. To evaluate the effects and mechanisms of catalpol on AD, both in vitro and in vivo studies were conducted. It was found that catalpol downregulated the phosphorylation of Lyn and Syk to inhibit various downstream pathways, including intracellular Ca elevation, cytokines generation, and histamine release, which ultimately controlled mast cell (MCs) degranulation. The results showed that catalpol alleviated AD-like skin lesions and MC infiltration via regulation of pro-Th2 and Th2 cytokines in vivo. Furthermore, this compound reduced the levels of IgE in AD mice and improved allergic reactions in PCA mice. The results provided that catalpol was potentially developed as a dietary supplement to improve AD and other atopic diseases.
Topics: Mice; Animals; Dermatitis, Atopic; Mast Cells; Dinitrochlorobenzene; Immunoglobulin E; Skin; Cytokines; Mice, Inbred BALB C
PubMed: 38041954
DOI: 10.1016/j.intimp.2023.111274 -
Biochemical and Biophysical Research... Dec 2022Thioredoxin (Trx) and glutathione disulfide (GSSG), are regenerated in reduced state by thioredoxin reductase (TrxR) and glutathione reductase (GR) respectively. A novel...
Thioredoxin (Trx) and glutathione disulfide (GSSG), are regenerated in reduced state by thioredoxin reductase (TrxR) and glutathione reductase (GR) respectively. A novel protein thioredoxin glutathione reductase (TGR) capable of reducing Trx as well as GSSG, linking two redox systems, has only been reported so far from parasitic flat worms and mammals. For the first time, we report a multifunctional antioxidant enzyme TGR from the nonparasitic, nonmammalian cnidarian Hydra vulgaris (HvTGR) which is a selenoprotein with unusual fusion of a TrxR domain with glutaredoxin (Grx) domain. We have cloned and sequenced HvTGR which encodes a polypeptide of 73 kDa. It contains conserved sequence CPYC of Grx domain, and CVNVGC and GCUG domains of thioredoxin reductase. Phylogenetic analysis revealed HvTGR to be closer to TGR from mammals rather than to TGR from parasitic helminths. We then subcloned HvTGR in plasmid pSelExpress-1 and expressed it in HEK293T cells to ensure selenocysteine incorporation. Purified HvTGR showed Grx, glutathione reductase and TrxR activities. Both thioredoxin and GSSG disulfide reductase activities were inhibited by 1-Chloro-2,4-dinitrobenzene (DNCB) supporting the existence of an essential selenocysteine residue. HvTGR expression was induced in response to HO in Hydra. Interestingly, inhibition of HvTGR by DNCB, inhibited regeneration in Hydra indicating its involvement in other cellular processes.
Topics: Animals; Humans; Thioredoxin-Disulfide Reductase; Glutathione Reductase; Hydra; Selenocysteine; Glutathione Disulfide; Hydrogen Peroxide; Phylogeny; Dinitrochlorobenzene; HEK293 Cells; Glutathione; Thioredoxins; Oxidation-Reduction; Antioxidants; Mammals
PubMed: 36375247
DOI: 10.1016/j.bbrc.2022.11.002 -
International Journal of... 2020Atopic dermatitis (AD) is a chronic inflammatory disease of the skin that substantially affects a patient's quality of life. While steroids are the most common therapy...
Atopic dermatitis (AD) is a chronic inflammatory disease of the skin that substantially affects a patient's quality of life. While steroids are the most common therapy used to temporally alleviate the symptoms of AD, effective and nontoxic alternatives are urgently needed. In this study, we utilized a natural, plant-derived phenolic compound, phloretin, to treat allergic contact dermatitis (ACD) on the dorsal skin of mice. In addition, the effectiveness of phloretin was evaluated using a mouse model of ACD triggered by 2,4-dinitrochlorobenzene (DNCB). In our experimental setting, phloretin was orally administered to BALB/c mice for 21 consecutive days, and then, the lesions were examined histologically. Our data revealed that phloretin reduced the process of epidermal thickening and decreased the infiltration of mast cells into the lesion regions, subsequently reducing the levels of histamine and the pro-inflammatory cytokines interleukin (IL)-6, IL-4, thymic stromal lymphopoietin (TSLP), interferon-γ (IFN-γ) and IL-17A in the serum. These changes were associated with lower serum levels after phloretin treatment. In addition, we observed that the mitogen-activated protein kinase (MAPK) and NF-κB pathways in the dermal tissues of the phloretin-treated rodents were suppressed compared to those in the AD-like skin regions. Furthermore, phloretin appeared to limit the overproliferation of splenocytes in response to DNCB stimulation, reducing the number of IFN-γ-, IL-4-, and IL-17A-producing CD4 T cells in the spleen back to their normal ranges. Taken together, we discovered a new therapeutic role of phloretin using a mouse model of DNCB-induced ACD, as shown by the alleviated AD-like symptoms and the reversed immunopathological effects. Therefore, we believe that phloretin has the potential to be utilized as an alternative therapeutic agent for treating AD.
Topics: Animals; Anti-Inflammatory Agents; CD4-Positive T-Lymphocytes; Cell Degranulation; Cytokines; Dermatitis, Allergic Contact; Dinitrochlorobenzene; Disease Models, Animal; Histamine; Histamine Release; Immunoglobulin E; Inflammation Mediators; Male; Mast Cells; Mice, Inbred BALB C; Phloretin; Signal Transduction; Skin
PubMed: 32571120
DOI: 10.1177/2058738420929442 -
Antioxidants (Basel, Switzerland) Jul 20227--methylluteolin (7-ML) is a flavonoid isolated from the aerial parts of (). We describe the anti-atopic dermatitis (AD) effects of 7-ML in tert-butyl hydroperoxide...
7--methylluteolin (7-ML) is a flavonoid isolated from the aerial parts of (). We describe the anti-atopic dermatitis (AD) effects of 7-ML in tert-butyl hydroperoxide (tBHP)-induced HepG2 cells and 2,4-dinitrochlorobenzene (DNCB)-induced SKH-1 hairless mice. Results demonstrated that 7-ML dose-dependently inhibited the activation of Nrf2 (nuclear factor-erythroid 2-related factor 2) in tBHP-induced HepG2 cells. 7-ML applied topically to our DNCB-induced mouse model upregulated the antioxidant protein expression (phosphorylated Nrf2 (pNrf2), Nrf2, and heme oxygenase-1 (HO-1)) in skin tissues, improved epidermal thickness, and reduced mast cell infiltration into the skin. In addition, 7-ML reduced the serum levels of immunoglobulin E (IgE) and interleukin-4 (IL-4) and improved skin barrier functions. These results suggest that 7-ML should be considered a novel antioxidant and anti-AD agent.
PubMed: 35883835
DOI: 10.3390/antiox11071344 -
Animal Cells and Systems 2021(Poaceae), also known as purple corn, is an annual herbaceous plant that is grown as food for human consumption in a variety of forms, including cooking oils and...
(Poaceae), also known as purple corn, is an annual herbaceous plant that is grown as food for human consumption in a variety of forms, including cooking oils and sweeteners in processed food and beverage products. The purpose of this study was to determine whether a novel purple corn extract, FB801, might have an anti-atopic dermatitis (AD) effect on AD-like skin lesions induced by 2,4-dinitrochlorobenzene (DNCB) in BALB/c mice. Topical sensitization (1%) and challenge (0.3%) by DNCB were performed on the dorsal skin and right ear of BALB/c mice to induce AD. Following FB801 and dexamethasone administered orally, the severity of skin lesions was examined macroscopically and histologically. Serum levels of immunoglobulin E (IgE) and various cytokines were determined by enzyme-linked immunosorbent assay. Oral administration of FB801 significantly reduced typical symptoms of AD (erythema/bleeding, swelling, molting/erosion and scaling/drying), scratching frequencies, and the recruitment of inflammatory and mast cells. In addition, FB801 suppressed serum levels of IgE and T helper (Th)2 type cytokines such as interleukin (IL)-4 and IL-10 in DNCB-treated BALB/c mice. Furthermore, FB801 reduced the degradation of inhibitor of nuclear factor-κB proteins (NF-κB) in tumor necrosis factor (TNF)-α-stimulated human keratinocyte (HaCaT) cells. These results suggest that FB801 inhibited the development of the AD-like skin symptoms by regulating Th1 and Th2 responses in the skin lesions in mice and suppressing TNF-α induced NF-κB activation in HaCaT cells, suggesting that FB801 has potential application as an effective alternative therapy for the prevention and management of AD.
PubMed: 34745434
DOI: 10.1080/19768354.2021.1974938 -
Pharmaceutics Jun 2023Oxyresveratrol (ORV) is one of the novel antioxidants having been extensively studied in recent years. One of the main sources of ORV is , which has been used in...
Oxyresveratrol (ORV) is one of the novel antioxidants having been extensively studied in recent years. One of the main sources of ORV is , which has been used in traditional medicine in Thailand for decades. However, the role of ORV in skin inflammation has not been clearly demonstrated. Therefore, we investigated the anti-inflammatory effects of ORV on dermatitis model. The effect of ORV was examined on human immortalized and primary skin cells exposed to bacterial components including peptidoglycan (PGN) and lipopolysaccharide (LPS) and 2,4-Dinitrochlorobenzene (DNCB)-induced dermatitis mouse model. PGN and LPS were used to induce inflammation on immortalized keratinocytes (HaCaT) and human epidermal keratinocytes (HEKa). We then performed MTT assay, Annexin V and PI assay, cell cycle analysis, real-time PCR, ELISA and Western blot in these in vitro models. H&E staining, immunohistochemistry (IHC) staining with CD3, CD4 and CD8 markers were used to evaluate the effects of ORV in in vivo model of skin inflammation using BALB/c mice. Pretreatment of HaCaT and HEKa cells with ORV inhibited pro-inflammatory cytokine production through inhibition of NF-κB pathway. In DNCB-induced dermatitis mouse model, ORV treatment reduced lesion severity, and skin thickness and numbers of CD3, CD4 and CD8 T cells in the sensitized skin of mice. In conclusion, it has been demonstrated that ORV treatment can ameliorate inflammation in the in vitro models of skin inflammation and in vivo models of dermatitis, suggesting a therapeutic potential of ORV for treatment of skin diseases particularly eczema.
PubMed: 37376157
DOI: 10.3390/pharmaceutics15061709 -
Frontiers in Pharmacology 2022Over the past few decades, complementary and alternative medicine (CAM) using herbs, or their active constituents have garnered substantial attention in the management...
Over the past few decades, complementary and alternative medicine (CAM) using herbs, or their active constituents have garnered substantial attention in the management of a chronic and relapsing inflammatory skin disorder called atopic dermatitis (AD), particularly in attenuating disease recurrence and maintaining long-term remission. In Eastern Asian countries including China, Korea and Taiwan, herbal medicine available in both topical and oral preparation plays a significant role in treating skin diseases like AD as they possibly confer high anti-inflammatory properties and immunomodulatory functions. Conventional murine models of AD have been employed in drug discovery to provide scientific evidence for conclusive and specific pharmacological effects elicited by the use of traditional herbs and their active constituents. Coupled with the goal to develop safe and effective novel therapeutic agents for AD, this systematic review consists of a summary of 103 articles on both orally and topically administered herbs and their active constituents in the murine model, whereby articles were screened and selected a specialized framework known as PICO (Population, Intervention, Comparator and Outcome). The objectives of this review paper were to identify the efficacy of oral and topical administered herbs along with their active constituents in alleviating AD and the underlying mechanism of actions, as well as the animal models and choice of inducer agents used in these studies. The main outcome on the efficacy of the majority of the herbs and their active constituents illustrated suppression of Th2 response as well as improvements in the severity of AD lesions, suppression of Immunoglobulin E (IgE) concentration and mast cell infiltration. The majority of these studies used BALB/c mice followed by NC/Nga mice (commonly used gender-male; commonly used age group - 6-8 weeks). The most used agent in inducing AD was 2, 4-Dinitrochlorobenzene (DNCB), and the average induction period for both oral and topical administered herbs and their active constituents in AD experiments lasted between 3 and 4 weeks. In light of these findings, this review paper could potentially assist researchers in exploring the potential candidate herbs and their active constituents using murine model for the amelioration of AD.
PubMed: 35685636
DOI: 10.3389/fphar.2022.785782