Eupatilin, an activator of PPARα, inhibits the development of oxazolone-induced atopic dermatitis symptoms in Balb/c mice

Exosomes derived from human dermal fibroblasts (HDFn-Ex) alleviate DNCB-induced atopic dermatitis (AD) via PPARα

Atopic dermatitis (AD) is a chronic inflammatory skin disease. Skin barrier dysfunction is the initial step in the development of AD. Recently, exosomes have been considered as potential cell-free medicine for skin defects such as aging, psoriasis and wounds. The aim of this study was to investigate the effects of human dermal fibroblast-neonatal-derived exosome (HDFn-Ex) on AD. HDFn-Ex increased the expression of peroxisome proliferator activated receptor α (PPARα) and alleviated the 1-chloro-2,4-dinitrobenzene (DNCB)-mediated downregulation of filaggrin, involucrin, loricrin, hyaluronic acid synthase 1 (HAS1) and HAS2 in human keratinocyte HaCaT cells. However, these effects were inhibited by the PPARα antagonist GW6471. In the artificial skin model, HDFn-Ex significantly inhibited DNCB-induced epidermal hyperplasia and the decrease in filaggrin and HAS1 levels via a PPARα. In the DNCB-induced AD-like mouse model, HDFn-Ex administration reduced epidermis thickening and mast cell infiltration into the dermis compared to DNCB treatment. Moreover, the decreases in PPARα, filaggrin and HAS1 expression, as well as the increases in IgE and IL4 levels induced by DNCB treatment were reversed by HDFn-Ex. These effects were blocked by pre-treatment with GW6471. Furthermore, HDFn-Ex exhibited an anti-inflammatory effect by inhibiting the DNCB-induced increases in IκBα phosphorylation and TNF-α expression. Collectively, HDFn-Ex exhibited a protective effect on AD. Notably, these effects were regulated by PPARα. Based on our results, we suggest that HDFn-Ex is a potential candidate for treating AD by recovering skin barrier dysfunction and exhibiting anti-inflammatory activity.

Eupatilin Ameliorates Lipopolysaccharide-Induced Acute Kidney Injury by Inhibiting Inflammation, Oxidative Stress, and Apoptosis in Mice

Acute kidney injury (AKI) is a common complication of sepsis. Eupatilin (EUP) is a natural flavone with multiple biological activities and has beneficial effects against various inflammatory disorders. However, whether EUP has a favorable effect on septic AKI remains unknown. Here, we examined the effect of EUP on lipopolysaccharide (LPS)-evoked AKI in mice. LPS-evoked renal dysfunction was attenuated by EUP, as reflected by reductions in serum creatinine and blood urea nitrogen levels. LPS injection also induced structural damage such as tubular cell detachment, tubular dilatation, brush border loss of proximal tubules, and upregulation of tubular injury markers. However, EUP significantly ameliorated this structural damage. EUP decreased serum and renal cytokine levels, prevented macrophage infiltration, and inhibited mitogen-activated protein kinase and NF-κB signaling cascades. Lipid peroxidation and DNA oxidation were increased after LPS treatment. However, EUP mitigated LPS-evoked oxidative stress through downregulation of NPDPH oxidase 4 and upregulation of antioxidant enzymes. EUP also inhibited p53-mediated apoptosis in LPS-treated mice. Therefore, these results suggest that EUP ameliorates LPS-evoked AKI through inhibiting inflammation, oxidative stress, and apoptosis.

Isolation of potent antileishmanial agents from Artemisia kermanensis Podlech using bioguided fractionation

Leishmaniasis is a major health problem worldwide with different clinical forms that depend on the parasite, the host's immune system, and immune-inflammatory responses. This study aimed to evaluate the secondary metabolites from Artemisia kermanensis Podlech by bioguided fractionation against Leishmania major. The chemical structures of the isolated compounds were determined based on analysis of mass and nuclear magnetic resonance spectra. Antileishmanial activity were determined on promastigotes and amastigotes. Chemical structures of the isolated compound were as 1-Acetoxy-3,7-dimethyl-7-hydroxy-octa-2E,5E-dien-4-one for compound 1 and 5,7-dihydroxy-3',4',6-trimethoxyflavone (Eupatilin) for compound 2, and 5,7,3'-Trihydroxy-6,4',5'-trimethoxyflavone for compound 3. Compound 2 were confirmed by significant activity with IC50 of less than 50 μg/ml for 24 and 48 h in clinical form (amastigotes). Compound 3 demonstrated high susceptibility with an IC50 of less than 30 μg/ml for promastigotes for 24 h. The bioguided fractionation of A. kermanensis resulted the isolation of potent antileishmanial agents with a low toxicity effect on macrophages. These plant metabolites can be a candidate as a drug for treating cutaneous leishmaniasis.

Xanthium spinosum L. Extracts Inhibit Breast Cancer in Mice by Apoptosis Induction and Immune System Modulation

Plants have been considered for many years as an important source of medicine to treat different diseases. Xanthium spinosum L. (Asteraceae, Compositae) is known for its diuretic, anti-inflammatory, and sedative effects. It is also used in the treatment of several ailments, such as cancer. In order to evaluate the anticancer and immunomodulatory activities, crude ethanol extract was prepared from the aerial part of X. spinosum and then fractionated using solvents with different polarities. As well, the chemical composition of X. spinosum extract and fractions were identified using LC-MS analysis. The antitumor effect of X. spinosum was assessed in both in vitro and in vivo models. Apoptosis induction was measured in vitro using a caspase-3 activity kit. Lymphocyte proliferation and phagocytosis and pinocytosis induction were used to quantify the effect of the plant extract and fractions on acquired and innate immunity, respectively. The effect of X. spinosum extract, and fractions on the levels of cytokines (IFN-γ, IL-2, IL-4, and IL-10) in murine lymphocytes was determined using a mouse-uncoated TH1/TH2 ELISA kit. Results showed that ethanol extract had the highest antiproliferative activity (IC₅₀ = 2.5 mg mL^-1) against EMT6/P cell lines, while the aqueous and chloroform fractions had the highest apoptotic activity with 2.2 and 1.7 folds, respectively. On the other hand, the n-hexane fraction was the most effective in stimulating lymphocyte proliferation, whereas ethanol extract, aq. Methanol and aqueous fractions exhibited the highest phagocytic activity. As well, X. spinosum extract and fractions were able to modulate the expression of IL-2, IL-4, and IFN-γ. A remarkable decrease in tumor size was accomplished following the treatment of tumor-bearing mice with X. spinosum extract and fractions. Both aq. Methanol and chloroform fractions showed the highest percentage change in tumor size with -58 and -55%, respectively. As well, tumor-bearing mice treated with chloroform fraction demonstrated a high curable percentage with a value of 57.1%. Anyway, X. spinosum extract and fractions exhibited no toxic impact on the liver or kidney functions of the mice-treated groups. These findings may confirm that X. spinosum has favorable anticancer and immunomodulatory effects. However, additional studies are required to fully understand the mechanisms of action of this plant and the signaling pathways involved in its effects. Moreover, more testing is needed to have better insight into the apoptotic pathway and to know the exact concentration of active compounds.

Eupatilin inhibits keratinocyte proliferation and ameliorates imiquimod-induced psoriasis-like skin lesions in mice via the p38 MAPK/NF-κB signaling pathway

BACKGROUND

Psoriasis is a chronic inflammatory skin disease that is currently incurable and causes long-term distress to patients. Therefore, there is an urgent need to develop safe and effective psoriatic drugs. Eupatilin is a natural flavone, that has a variety of pharmacological effects. However, the anti-psoriatic effect of eupatilin and its underlying mechanism remain unclear.

METHODS

HaCaT cells were treated with 20 μg/mL LPS for 24 h to establish the proliferation model of HaCaT cells. Cell viability was measured by MTT assay. Western blotting was used to detect the expression of p-p38 MAPK, p38 MAPK, p-NF-κB p65 and NF-κB p65 in HaCaT cells. Imiquimod (IMQ) was used to induce psoriasis-like mouse model. Psoriasis Area Severity Index (PASI) score was used to evaluate the degree of skin injury, H&E staining was used to observe the pathological damage of skin tissues, and the expression levels of TNF-α, IL-6, IL-23 and IL-17 in the serum were detected by enzyme-linked immunosorbent assay (ELISA).

RESULTS

Eupatilin could inhibit the hyperproliferation of LPS-stimulated HaCaT cells through p38 MAPK/NF-κB signaling pathway in vitro. In psoriatic mice, eupatilin could significantly reduce skin erythema, scales and thickening scores, ameliorate skin histopathological lesions, and decrease the levels of TNF-α, IL-6, IL-23 and IL-17 in the serum.

CONCLUSION

Eupatilin had a good anti-proliferative effect in LPS-stimulated HaCaT cells, and significantly alleviated IMQ-induced psoriasis-like lesions in mice. Eupatilin was a promising drug for the treatment of psoriasis.

Protective Effects of Topical Administration of Laminarin in Oxazolone-Induced Atopic Dermatitis-like Skin Lesions

Laminarin is a polysaccharide isolated from brown marine algae and has a wide range of bioactivities, including immunoregulatory and anti-inflammatory properties. However, the effects of laminarin on atopic dermatitis have not been demonstrated. This study investigated the potential effects of topical administration of laminarin using a Balb/c mouse model of oxazolone-induced atopic dermatitis-like skin lesions. Our results showed that topical administration of laminarin to the ear of the mice improved the severity of the dermatitis, including swelling. Histological analysis revealed that topical laminarin significantly decreased the thickening of the epidermis and dermis and the infiltration of mast cells in the skin lesion. Serum immunoglobulin E levels were also significantly decreased by topical laminarin. Additionally, topical laminarin significantly suppressed protein levels of oxazolone-induced proinflammatory cytokines, such as interleukin-1β, tumor necrosis factor-α, monocyte chemoattractant protein-1, and macrophage inflammatory protein-1α in the skin lesion. These results indicate that topical administration of laminarin can alleviate oxazolone-induced atopic dermatitis by inhibiting hyperproduction of IgE, mast cell infiltration, and expressions of proinflammatory cytokines. Based on these findings, we propose that laminarin can be a useful candidate for the treatment of atopic dermatitis.

Investigating the Role of Dahuang in Hepatoma Treatment Using Network Pharmacology, Molecular Docking, and Survival Analysis

Hepatoma is one of the most common malignant tumors. The incidence rate is high in developing countries, and China has the most significant number of cases. Dahuang is a classic traditional antitumor drug commonly used in China and has also been applied to treat hepatoma. However, the potential mechanism of Dahuang in treating hepatoma is not clear. Therefore, this study is aimed at elucidating the possible molecular mechanism and key targets of Dahuang using methods of network pharmacology, molecular docking, and survival analysis. Firstly, the active ingredients and key targets of Dahuang were analyzed through public databases, and then the drug-ingredient-target-disease network diagram of Dahuang against hepatoma was constructed. Five main active components and five core targets were determined according to the enrichment degree. Enrichment analysis demonstrated that Dahuang treated hepatoma through the multiple pathways in cancer. Additionally, molecular docking predicted that aloe-emodin and PIK3CG depicted the best binding energy. Survival analysis indicated that a high/ESR1 gene expression had a relatively good prognosis for patients with hepatoma (p < 0.05). In conclusion, the current study results demonstrated that Dahuang could treat hepatoma through a variety of active ingredients, targets, and multiantitumor pathways. Moreover, it effectively improved the prognosis of hepatoma patients. ESR1 is the potential key gene that is beneficial for the survival of hepatoma patients. Also, aloe-emodin and beta-sitosterol are the two main active crucial ingredients for hepatoma treatment. The study also provided some functional bases and references for the development of new drugs, target mining, and experimental animal research of hepatoma in the future.

CD147 Mediates 5-Fluorouracil Resistance in Colorectal Cancer by Reprogramming Glycolipid Metabolism

Chemoresistance against 5-fluorouracil (5-FU) is a major issue for colorectal cancer (CRC) patients. Increasing evidence for the roles of CD147 in glycolipid metabolic reprogramming and chemoresistance of tumor cells has emerged in recent years. However, whether CD147 contributes to 5-FU resistance in CRC and the role of abnormal glycolipid metabolism in this process remain poorly understood. We analyzed CD147 expression in primary tumor samples of CRC patients and found that upregulated CD147 correlated with decreased 5-FU chemosensitivity and an unfavorable prognosis of CRC patients. Moreover, in vivo and in vitro experiments confirmed that CD147 regulates glycolipid metabolism through two separate pathways. Mechanistically, CD147 upregulates HIF-1α-mediated glycolysis by activating the PI3K/AKT/mTOR pathway and CD147 also attenuates PPARα-mediated fatty acid oxidation by activation of the MAPK pathway. Most importantly, we found that CD147 confers 5-FU resistance in CRC via these glycolipid metabolic signatures. Our results demonstrated that CD147 is a potential 5-FU resistance biomarker for CRC patients and a candidate therapeutic target to restore 5-FU sensitivity of 5-FU-resistant CRC by remodeling glycolipid metabolism.

Management of Atopic Dermatitis Via Oral and Topical Administration of Herbs in Murine Model: A Systematic Review

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 via 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.

Anti-Irritant Strategy against Retinol Based on the Genetic Analysis of Korean Population: A Genetically Guided Top-Down Approach

Retinol, one of the most powerful cosmetic materials for anti-aging supported by a solid scientific background, exhibits a wide range of type and severity of irritation while showing limited user compliance. The lack of understanding of the mechanism of retinol-induced irritation has been the main hurdle in the development of anti-irritation strategies. Here, we identified 30 genetic markers related to the susceptibility to retinol-induced irritation in the Korean population. Based on the genetic analysis, a novel formula against retinol-induced irritation was developed, which mitigated the molecular pathogenesis—as indicated by the genetic markers—of the retinol-induced irritation. In human tests, this formula effectively decreased retinol-induced irritation. Furthermore, a polygenic risk score model for irritation was constructed and validated. Our comprehensive approach for the analysis of retinol-induced irritation will not only aid the development of anti-irritation strategies to ensure higher user compliance but also contribute to improving the current knowledge about the biological effects of retinoids.

Anti-Allergic Effect of Low Molecular Weight Digest from Abalone Viscera on Atopic Dermatitis-Induced NC/Nga

Abalone viscera (AV) is one of the byproducts of the seafood processing industry. The low molecular weight (<5 kDa) peptides (LMW-AV) obtained from gastrointestinal digestion of AV could suppress allergenic responses on activated HMC-1 human mast cells in our previous study. Regarding the allergenic response of LMW-AV, in the present study, we further investigated the potential of oral administration of LMW-AV against atopic dermatitis (AD) in a dermatitis-induced model stimulated with Dermatophagoides farinae. The results demonstrated that the LMW-AV reduced a number of clinical symptoms, such as the severity of the dermatitis and serum immunoglobulin E levels. Moreover, LMW-AV could inhibit the expression of chemokines and cytokines. The histological analysis indicated that the LMW-AV has suppressed the eosinophil count and the mast cell infiltration into the upper dermis. The results suggest that LMW-AV can be considered as a promising candidate for AD treatment.

Anti-inflammatory effects of a novel phosphodiesterase-4 inhibitor, AA6216, in mouse dermatitis models

Atopic dermatitis (AD) is a chronic inflammatory skin disease that is commonly treated with corticosteroids. However, these drugs have long-term adverse effects, representing an unmet need for new treatments. AD is associated with dysregulation of phosphodiesterase 4 (PDE4) activity in inflammatory cells and the topical PDE4 inhibitor, crisaborole, is approved by the US FDA for mild-to-moderate AD. In this study, we compared the effects of a novel PDE4 inhibitor, AA6216, with those of crisaborole on skin inflammation. We found that AA6216 is a more potent inhibitor of PDE4 and of cytokine production (TNF-α, IL-12/23p40, IL-4, IL-13, and IFN-γ) by human peripheral blood mononuclear cells (PBMCs) stimulated by phytohemagglutinin (PHA) or anti-CD3 antibodies, with IC₅₀ values ranging from 5.9 to 47 nM. AA6216 also significantly suppressed skin inflammation in three mouse models of dermatitis. In acute and chronic oxazolone-induced dermatitis models, topical AA6216 exhibited stronger inhibitory effects on ear inflammation and cytokine production (TNFα, IL-1β, and IL-4) in skin lesions compared with crisaborole. In a Dermatophagoides farinae-induced dermatitis model, AA6216 significantly reduced the dermatitis score, based on the development of erythema/hemorrhage, scarring/dryness, edema, and excoriation/erosion, compared with a clinically used topical AD drug, tacrolimus. These results suggest the possibility that AA6216 is a novel and effective topical therapeutic agent for the treatment of dermatitis including AD.

Two Types of PPARγ Ligands Identified in the Extract of Artemisia campestris

The 70% ethanol extract of Artemisia campestris was screened to find PPARγ ligands using the PPARγ ligand-responsive chimera luciferase reporter system. Capillartemisin B was identified as a PPARγ ligand that stimulated lipid accumulation in 3T3-L1 cells. By further purification of PPARγ ligands from a large-scale preparation of the methanol extract of Artemisia campestris, we isolated and identified eupatilin and santaflavone as PPARγ ligands. Weak PPARγ ligand activity of eupatilin or santaflavone in reporter assay was enhanced by a PPARγ antagonist, GW9662, suggesting that santaflavone or eupatilin and GW9662 bound simultaneously to the multiple sub-pockets of the PPARγ ligand-binding domain (LBD) and cooperatively activated PPARγ. Docking simulation suggested that eupatilin binds to the Ω-pocket but not to the AF-2 pocket of Y-shaped PPARγ LBD where artepillin C that differs from capillartemisin B at the C-5′ position without hydroxy group binds. Eupatilin or santaflavone with or without GW9662 did not stimulate lipid accumulation in differentiated 3T3-L1 cells, suggesting that binding of each compound alone or with GW9662 to the Ω-pocket which stimulated the PPARγ-responsive reporter expression was not enough to stimulate lipid accumulation. The PPARγ ligands found in this study have a potential to design the fragment-based drug design of a novel PPARγ ligand that cover the Y-shaped PPARγ LBD.

Effects of mineral complex material treatment on 2,4- dinitrochlorobenzene-induced atopic dermatitis like-skin lesions in mice model

Background

Atopic dermatitis (AD) is a chronic allergic inflammatory skin disease characterized by complex pathogenesis including skin barrier dysfunction, immune-redox disturbances, and pruritus. Prolonged topical treatment with medications such as corticosteroids, calcineurin inhibitors, and T-cell inhibitors may have some potential side-effects. To this end, many researchers have explored numerous alternative therapies using natural products and mineral compounds with antioxidant or immunomodulatory effects to minimize toxicity and adverse-effects. In the current study, we investigated the effects of mineral complex material (MCM) treatment on 2, 4-dinitrochlorobenzene (DNCB)-induced AD-like skin lesions in SKH-1 hairless mice.

Methods

Animals were divided into four groups; normal control (NC), negative control treated with DNCB only (DNCB only), positive control treated with DNCB and tacrolimus ointment (PC) and experimental group treated with DNCB and MCM patch (MCM). Skin inflammation and lesion severity were investigated through analyses of skin parameters (barrier score and strength, moisture and trans-epidermal water loss level), histopathology, immunoglobulin E, and cytokines. In addition, reactive oxygen species (ROS), nitric oxide (NO), glutathione peroxidase (GPx), and catalase (CAT) levels were measured in both serum and skin lysate.

Results

Our results demonstrates that MCM patch improved the progression of AD-like skin lesions by significantly increasing skin barrier strength and decreasing trans-epidermal water loss. Additionally, dermal administration of MCM patch significantly reduced epidermal thickness, ROS, and NO levels in skin lysate. Furthermore, we found that MCM suppressed the levels of AD-involved (Th₁ and Th₂) cytokines such as IL-2, IFN-γ, and IL-4 in blood. In addition, the levels of other Th_1, and Th₂ and inflammatory cytokines such as IL-1β, TNF-α, IL-6, IL-12(p70) and IL-10 were found lowest in the MCM group than in the DNCB only and PC groups. Moreover, we found total serum IgE level significantly increased after DNCB treatment, but decreased in the PC and MCM groups.

Conclusion

Taken together, our findings suggest that MCM application may have beneficial effects either systemic or regional on DNCB-induced AD lesional skin via regulation of the skin barrier function and immune-redox response.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12906-021-03259-5.

Comparative Study on Different Skin Pruritus Mouse Models

The animal model is an important tool to study the mechanism of disease formation. Different animal models of pruritus have been adopted based on the purpose of researchers in the study of the itching mechanism. Although the symptoms of various models are quite different, scratching behavior is a key indicator. Therefore, it is necessary to find an animal model that can quickly induce animal scratching and maintain the stability of scratching behavior. In this study, we compared animal models of pruritus induced by four substances and found that the scratching behavior of mice induced by urushiol not only reached the plateau stage quickly but also showed more stability in the plateau phase than that induced by 2,4-dinitrofluorobenzene, oxazolone, and imiquimod. Meanwhile, in the animal model induced by urushiol, the changes of epidermal thickening and inflammatory cell aggregation were also more obvious. In addition, pruritus induced by urushiol is prevalent all over the world, especially in the United States and Europe, involving outdoor groups such as firefighters, forest loggers, and farmers. Therefore, we believe that the urushiol-induced animal model is an ideal choice for the study of the itch formation mechanism and the development of antipruritic drugs.

Effects of Particulate Matter in a Mouse Model of Oxazolone-Induced Atopic Dermatitis

BACKGROUND

Recent epidemiological studies have demonstrated that air pollution is associated with the inflammatory response and may aggravate inflammatory skin diseases such as atopic dermatitis (AD). However, it is unclear whether particulate matter (PM) aggravates AD symptoms.

OBJECTIVE

The aim of this study was to investigate whether PM exposure affects the skin barrier dysfunction and aggravates AD symptoms using human keratinocytes (HaCaT) cells and a mouse model of oxazolone-induced AD-like skin.

METHODS

Standard reference material (SRM) 1649b, which mainly comprises polycyclic aromatic hydrocarbons, was used as the reference PM. HaCaT cells and mouse model of oxazolone-induced AD-like skin were treated with PM. The mRNA or protein expression levels of stratum corneum (SC) and tight junction (TJ) proteins, inflammatory cytokines, as well as clinical and histological changes of the AD-like skin of mouse model were evaluated. The expression of genes and proteins was analyzed by real-time polymerase chain reaction and Western blotting. Levels of inflammatory cytokines were measured by enzyme-linked immunosorbent assay.

RESULTS

The results revealed that PM downregulates the expression levels of several SC and TJ-related proteins in the mouse model with AD-like skin. Clinically, epidermal and dermal thickness was significantly increased and dermal inflammation was prominent in PM treated AD-like skin.

CONCLUSION

In conclusion, we found that PM aggravates skin barrier dysfunction, clinically augmenting epidermal and dermal thickening with dermal inflammation in AD-like skin. These results suggest that PM may trigger the exacerbation of AD symptoms via skin barrier dysfunction-related mechanisms.

HP-NAP ameliorates OXA-induced atopic dermatitis symptoms in mice

BACKGROUND

Atopic dermatitis (AD) is a chronic skin inflammatory disease characterized by disequilibrium between Th1/Th2 lymphocytes. Helicobacter pylori neutrophil-activating protein (HP-NAP) has been reported that it has the potential immunomodulatory effect able to regulate the Th1/Th2 balance.

OBJECTIVE

This study aimed to investigate the therapeutic effect of HP-NAP in AD mice model.

METHODS

The model of AD was built with oxazolone (OXA) in BALB/c mice, then HP-NAP was used to treat AD by intraperitoneal injection. Ear thickness was measured by a digital thickness gauge. The ears tissues were collected and subjected to hematoxylin-eosin (H&E) and toluidine blue (TB) staining. The mRNA expression levels of inflammatory cytokines (IL-1β, IL-5, IL-6, and TNF-α) in ear tissue were measured using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The secretion of IgE, IL-4, and IFN-γ was measured by enzyme-linked immunosorbent assay (ELISA).

RESULTS

Treatment with HP-NAP successfully alleviated the symptoms of AD, such as erythema, horny substance, and swelling. The infiltration of lymphocytes and mast cells were significantly reduced following HP-NAP therapy. The secretion of IgE and IL-4 was significantly attenuated following treatment with HP-NAP. Additionally, HP-NAP observably downregulated inflammatory cytokine expression (e.g. IL-1β, IL-5, IL-6, and TNF-α) in ear tissues.

CONCLUSIONS AND CLINICAL RELEVANCE

Taken together, our results showed that HP-NAP possessed the potential to be a novel immunomodulatory candidate drug against AD.

Eupatilin prevents behavioral deficits and dopaminergic neuron degeneration in a Parkinson's disease mouse model

AIMS

Neuroinflammation and apoptosis play a crucial role in Parkinson's disease (PD) pathogenesis. Eupatilin is a lipophilic flavonoid isolated from Artemisia species and exerts anti-apoptotic and anti-inflammatory activities. In this study, we investigated the effects of Eupatilin on a mouse model of PD induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP).

MAIN METHODS

The rotarod test and traction test were constructed to examine the motor function. Immunofluorescent staining was performed to detect the expression of TH, Iba-1 and GFAP. Apoptosis was examined by the TUNEL assay. Real-time PCR was used to determine the mRNA expression and Western blot and ELISA were used to determine the protein expression.

KEY FINDINGS

Eupatilin improved behavioral impairment caused by MPTP. A loss of TH positive neurons was observed in the substantia nigra pars compacta of MPTP-lesioned brain, while it was rescued by Eupatilin. Moreover, MPTP administration increased the cell number of microglia and astrocytes and the expression of inflammatory factors TNF-α, IL-1β, and IL-6. Whereas Eupatilin suppressed the activation of neuroinflammation. Eupatilin also decreased cell apoptosis enhanced by MPTP/MPP⁺ exposure in vivo and in vitro. We further revealed that Eupatilin abolished MPTP-induced downregulation of IκBα expression and accumulation of p65 in the nuclear compartment. Besides, MPTP administration led to dephosphorylation of Akt and GSK-3β, but it was restored by Eupatilin.

SIGNIFICANCE

We demonstrate that Eupatilin alleviates behavioral impairment and dopaminergic neuron loss induced by MPTP through inhibition of neuroinflammation and apoptosis. Our research provides more evidence for Eupatilin as a potential preventative drug for PD.

Eupatilin regulates proliferation and cell cycle of cervical cancer by regulating hedgehog signalling pathway

Eupatilin (5,7-dihydroxy-3',4',6-trimethoxyflavone) is a natural active substance found in génépi group plants, and its pharmacological activities has been proven to be useful in the treatment of various cancers. However, whether eupatilin demonstrates anti-cancer activity in cervical cancer is still under evaluation. To clarify this, cancer cell lines and nude mouse model were used in this study. The results indicated that eupatilin could inhibit the occurrence of cervical cancer both in vivo and in vitro. Cervical cancer cell lines (C4-1, HeLa, Caski, and Siha) and Ect1/E6E7 cells were incubated with eupatilin (40μM) for 48 hours. Compared with the control group, the viability of cervical cancer cells decreased significantly, while the apoptotic cells increased significantly. Cell cycle analysis showed that eupatilin treatment of HeLa and Caski cells reduced the proliferation index. Eupatilin at 40 mg/kg also inhibited tumour growth in tumour-bearing mice. Interestingly, weakened hedgehog signalling was observed in cervical cancer cells and tumours from tumour-bearing mice after eupatilin treatment. Our results reveal the inhibitory effect of eupatilin on cervical cancer and shed new light on the molecular mechanism of its therapeutic effect. SIGNIFICANCE OF THE STUDY: Eupatilin inhibited proliferation via promoting apoptosis and cell cycle arrest in HeLa and Caski cervical cancer cell lines. In addition, nude mouse tumourigenicity assay proved that eupatilin can suppress tumour growth in vivo. Dramatically, these activities might be involved in hedgehog signal pathway.

Immunotoxicity and allergenic potential induced by topical application of perfluorooctanoic acid (PFOA) in a murine model

Perfluorooctanoic acid (PFOA) is a per- and polyfluoroalkyl substance (PFAS) once used as a surfactant in the polymerization of chemicals. Because of its ubiquitous nature and long half-life, PFOA is commonly detected in the environment, wildlife, and humans. While skin exposure to PFOA is of concern, studies evaluating the immunotoxicity of dermal exposure are lacking. These studies evaluated the immunotoxicity of PFOA (0.5-2% w/v, or 12.5-50 mg/kg/dose) following dermal exposure using a murine model. PFOA (0.5-2%) was not identified to be an irritant or sensitizer using the local lymph node assay. The IgM antibody response to sheep red blood cell. was significantly reduced in the spleen following 4-days of dermal exposure (2%). PFOA exposure produced a significant decrease in thymus (1 and 2%) and spleen (0.5-2%) weight along with an increase in liver weight (0.5-2%). Immune cell phenotyping identified a reduction in the frequency (1 and 2%) and number (0.5-2%) of splenic B-cells. To further define the mechanism of immunotoxicity, gene expression was also evaluated in the skin. The findings support a potential involvement of the nuclear receptor PPARα. These results demonstrate that dermal exposure to PFOA is immunotoxic and raise concern about potential adverse effects from dermal exposure.

Anti-Atopic Effect of Acorn Shell Extract on Atopic Dermatitis-Like Lesions in Mice and Its Active Phytochemicals

To investigate the potential effects of acorn shells on atopic dermatitis (AD), we utilized oxazolone (OX)- or 2,4-dinitrochlorobenzene (DNCB)-induced AD-like lesion mouse models. Our research demonstrates that Acorn shell extract (ASE) improved the progression of AD-like lesions, including swelling, which were induced by oxazolone on Balb/c mouse ears. Additionally, ASE significantly decreased the ear thickness (OX: 0.42 ± 0.01 mm, OX-ASE: 0.32 ± 0.02 mm) and epidermal thickness (OX: 75.3 ± 32.6 µm, OX-ASE: 46.1 ± 13.4 µm). The continuous DNCB-induced AD mouse model in SKH-1 hairless mice demonstrated that ASE improved AD-like symptoms, including the recovery of skin barrier dysfunction, Immunoglobulin E hyperproduction (DNCB: 340.1 ± 66.8 ng/mL, DNCB-ASE: 234.8 ± 32.9 ng/mL) and an increase in epidermal thickness (DNCB: 96.4 ± 21.9 µm, DNCB-ASE: 52.4 ± 16.3 µm). In addition, we found that ASE suppressed the levels of AD-involved cytokines, such as Tumor Necrosis Factor α, IL-1β, IL-25 and IL-33 in both animal models. Furthermore, gallic acid and ellagic acid isolated from ASE suppressed β-hexosaminidase release and IL-4 expression in RBL-2H3 cells. The acorn shell and its active phytochemicals have potential as a new remedy for the improvement of atopic dermatitis and other inflammatory diseases.

Fucoidan from seaweed Fucus vesiculosus inhibits 2,4-dinitrochlorobenzene-induced atopic dermatitis

Fucoidan, one activator of scavenger receptor class A (SR-A), plays important roles in a variety of biological activities, including anti-inflammatory, antioxidant, and antitumor actions. However, the effects of fucoidan on atopic dermatitis (AD) have not been elucidated. To assess this, 2,4-dinitrofluorobenzene (DNFB)-treated BALB/c mice were painted with fucoidan. Results showed that fucoidan significantly ameliorated ear swelling, improved abdomen skin lesions, and decreased inflammatory cell infiltration. In addition, fucoidan significantly suppressed the serum levels of IgE and IL-4 in DNFB-induced AD mice. The infiltration of CD4+ T cells in skin lesions and spleen was also reduced in fucoidan-treated AD mice. Furthermore, treatment with fucoidan promoted Treg cells but attenuated Th1/17 response in the spleens from DNFB-induced AD mice. Together, these results suggest that fucoidan, a natural seaweed-rich polysaccharide, has a potential therapeutic efficacy in the treatment of AD, correlates with the induction of higher anti-inflammatory response through inducing Treg cells.

Peroxisomes and Oxidative Stress: Their Implications in the Modulation of Cellular Immunity During Mycobacterial Infection

Host redox dependent physiological responses play crucial roles in the determination of mycobacterial infection process. Mtb explores oxygen rich lung microenvironments to initiate infection process, however, later on the bacilli adapt to oxygen depleted conditions and become non-replicative and unresponsive toward anti-TB drugs to enter in the latency stage. Mtb is equipped with various sensory mechanisms and a battery of pro- and anti-oxidant enzymes to protect themselves from the host oxidative stress mechanisms. After host cell invasion, mycobacteria induces the expression of NADPH oxidase 2 (NOX2) to generate superoxide radicals (O 2 - ), which are then converted to more toxic hydrogen peroxide (H2O2) by superoxide dismutase (SOD) and subsequently reduced to water by catalase. However, the metabolic cascades and their key regulators associated with cellular redox homeostasis are poorly understood. Phagocytosed mycobacteria en route through different subcellular organelles, where the local environment generated during infection determines the outcome of disease. For a long time, mitochondria were considered as the key player in the redox regulation, however, accumulating evidences report vital role for peroxisomes in the maintenance of cellular redox equilibrium in eukaryotic cells. Deletion of peroxisome-associated peroxin genes impaired detoxification of reactive oxygen species and peroxisome turnover post-infection, thereby leading to altered synthesis of transcription factors, various cell-signaling cascades in favor of the bacilli. This review focuses on how mycobacteria would utilize host peroxisomes to alter redox balance and metabolic regulatory mechanisms to support infection process. Here, we discuss implications of peroxisome biogenesis in the modulation of host responses against mycobacterial infection.

Effect of Topically Applied Wikstroemia dolichantha Diels on the Development of Atopic Dermatitis-Like Skin Symptoms in Mice

Plants of the genus Wikstroemia are traditionally used to treat inflammatory diseases like bronchitis and rheumatoid arthritis. In the present study, the anti-atopic effects of an EtOH extract of Wikstroemia dolichantha (WDE) on oxazolone- and DNCB (2,4-dinitrochlorobenzene)-induced dermatitis in mice were investigated. Both ears of BALB/c mice were exposed to oxazolone, and dorsal skins of SKH-1 hairless mice were sensitized with DNCB to induce acute eczematous atopic skin lesions. 1% WDE was applied daily to oxazolone- and DNCB-induced AD mice for two or three weeks, respectively. Total IL-4 and IgE concentrations in serum, transepidermal water loss (TEWL) and skin hydration were assessed. High-performance liquid chromatography/mass spectrometry (HPLC/MS) was used to determine the composition of WDE. Dermal application of 1% WDE grossly and histopathologically improved oxazolone- and DNCB-induced AD skin symptoms. Epidermal thickness and mast cell infiltration were significantly lower in animals treated with WDE than in vehicle controls. Furthermore, in addition to reducing DNCB-induced increases in serum IL-4 (interleukin 4) and IgE (immunoglobulin E) levels, WDE also decreased TEWL and increased skin hydration (indicative of improved skin barrier function). The four flavonoids taxifolin, aromadendrin, padmatin and chamaejasmine were tentatively identified in WDE by HPLC-DAD/QTOF-MS. The above results show WDE protected against oxazolone- and DNCB-induced AD in mice by down-regulating the T_H2-associated cytokine IL-4 and improving skin barrier function and suggest WDE might be useful for the management of atopic dermatitis.

IL33: Roles in Allergic Inflammation and Therapeutic Perspectives

Interleukin (IL)-33 belongs to IL-1 cytokine family which is constitutively produced from the structural and lining cells including fibroblasts, endothelial cells, and epithelial cells of skin, gastrointestinal tract, and lungs that are exposed to the environment. Different from most cytokines that are actively secreted from cells, nuclear cytokine IL-33 is passively released during cell necrosis or when tissues are damaged, suggesting that it may function as an alarmin that alerts the immune system after endothelial or epithelial cell damage during infection, physical stress, or trauma. IL-33 plays important roles in type-2 innate immunity via activation of allergic inflammation-related eosinophils, basophils, mast cells, macrophages, and group 2 innate lymphoid cells (ILC2s) through its receptor ST2. In this review, we focus on the recent advances of the underlying intercellular and intracellular mechanisms by which IL-33 can regulate the allergic inflammation in various allergic diseases including allergic asthma and atopic dermatitis. The future pharmacological strategy and application of traditional Chinese medicines targeting the IL-33/ST2 axis for anti-inflammatory therapy of allergic diseases were also discussed.