A two-sample Mendelian randomization study of mutual relations of six types of diets in atopic dermatitis.

BACKGROUND: In the continuous endeavor to find safe and efficient treatments for Atopic Dermatitis (AD), there remains a considerable focus on dietary adjustments. Nevertheless, the limited availability of research and conflicting findings in the academic literature pose a hurdle in establishing conclusive recommendations. METHOD: Mendelian randomization (MR) was applied to the most comprehensive genome-wide association studies (GWAS) data on tea intake (447 485), green tea intake (n = 64 949), flavored milk intake (n = 64 941), never eat eggs, dairy, wheat, sugar: Wheat products(n = 461 046), never eat eggs, dairy, wheat, sugar: Sugar or foods/drinks containing sugar (n = 461 046), never eat eggs, dairy, wheat, sugar: I eat all of the above (n = 461 046) and atopic dermatitis (n = 218 467). We used the inverse-variance weighted method (IVW) as the primary method. RESULTS: The IVW analyses have demonstrated an increased tea intake was genetically associated with a reduced risk of AD (odds ratio [OR]: 0.646, 95% confidence interval [CI]: 0.430-0.968, p = 0.034). Furthermore, green tea intake was significantly negatively associated with AD (IVW OR: 0.986, 95% CI: 0.975-0.998; p = 0.024) in the IVW model. AD risk could be reduced by never eating wheat products (IVW OR: 8.243E-04, 95% CI: 7.223E-06-9.408E-02, p = 0.003). There was no association between never eating eggs, dairy, wheat, sugar: Sugar, or foods/drinks containing sugar, I eat all of the above and AD. CONCLUSIONS: Our MR study suggests a causal relationship between tea intake, green tea intake, and the avoidance of eating wheat products with atopic dermatitis. Our findings recommend that preventing and managing atopic dermatitis may be achieved by never eating wheat products while increasing tea and green tea intake.

Gu-Ben-Hua-Shi (AESS) formula ameliorates atopic dermatitis via regulating NLRP3 signaling pathways.

Background: Gu-ben-hua-shi (AESS) formula is a clinical experienced prescription from Guangdong Hospital of Traditional Chinese Medicine (TCM), which is used to treat atopic dermatitis (AD). Our previous work has shown that AESS has therapeutic effect on AD by regulating yes-associated protein (YAP). AESS formula has multi-component and multi-target characteristic, and need to be analyzed by systematic chemical profiling and network pharmacology technology, as well as verification of key signaling pathways. Therefore, this study aimed at investigating the efficacy and effect of AESS formula in the treatment of AD and its effect on NLRP3 signaling pathway. Methods: The components of AESS formula were analyzed and identified by ultra high performance liquid chromatography/tandem mass spectrometry (UHPLC- MS/MS), and the potential mechanism of AESS formula in the treatment of AD was predicted by network pharmacology approach, with detected main components, and the potential components targeted NOD-like receptor thermal protein domain associated protein (NLRP3) signaling pathway [Direct binding with NLRP3, apoptosis-associated speck-like protein (ASC) and Caspase-1] were assessed using molecular docking. AD-like symptoms were constructed by DNCB induced BALB/c mice. The effect of AESS formula on dorsal skin structure in AD-like mice was observed using H&E staining. Furthermore, the western blotting experiment explored the expression of the NLRP3 pathway protein. Results: By UHPLC-MS/MS analysis, 91 compounds were detected in AESS formula, and 76 of them were identified, while by network pharmacological analysis, 1500 component targets were obtained, and 257 of them were obtained by intersection with eczema targets. Then one of the key pathways, nucleotide-binding oligomerization domain (NOD)-like signaling pathway was obtained by KEGG enrichment analysis. Molecular docking results showed 24 main components could effectively combine with ASC and Caspase-1 (≤-7 kcal/mol). The animal experiment results further showed that AESS formula alleviates symptoms in AD-like mice. ELISA kit results showed that the expression of IL-1ß and IL-18 in serum was inhibited after AESS treatment. Additionally, western blotting analysis showed that the expressions of ASC, Caspase-1 and NLRP3 protein expression in the skin tissue of mice were down-regulated after AESS treatment. The experimental results show that AESS formula inhibited the expression of NLRP3 signaling pathway for the treatment of AD. Conclusions: AESS formula can improve AD symptoms in mice by inhibiting the activation of NLRP3 inflammasome and the expression of the related downstream inflammatory cytokines.

Construction and verification of atopic dermatitis diagnostic model based on pyroptosis related biological markers using machine learning methods.

OBJECTIVE: The aim of this study was to construct a model used for the accurate diagnosis of Atopic dermatitis (AD) using pyroptosis related biological markers (PRBMs) through the methods of machine learning. METHOD: The pyroptosis related genes (PRGs) were acquired from molecular signatures database (MSigDB). The chip data of GSE120721, GSE6012, GSE32924, and GSE153007 were downloaded from gene expression omnibus (GEO) database. The data of GSE120721 and GSE6012 were combined as the training group, while the others were served as the testing groups. Subsequently, the expression of PRGs was extracted from the training group and differentially expressed analysis was conducted. CIBERSORT algorithm calculated the immune cells infiltration and differentially expressed analysis was conducted. Consistent cluster analysis divided AD patients into different modules according to the expression levels of PRGs. Then, weighted correlation network analysis (WGCNA) screened the key module. For the key module, we used Random forest (RF), support vector machines (SVM), Extreme Gradient Boosting (XGB), and generalized linear model (GLM) to construct diagnostic models. For the five PRBMs with the highest model importance, we built a nomogram. Finally, the results of the model were validated using GSE32924, and GSE153007 datasets. RESULTS: Nine PRGs were significant differences in normal humans and AD patients. Immune cells infiltration showed that the activated CD4+ memory T cells and Dendritic cells (DCs) were significantly higher in AD patients than normal humans, while the activated natural killer (NK) cells and the resting mast cells were significantly lower in AD patients than normal humans. Consistent cluster analysis divided the expressing matrix into 2 modules. Subsequently, WGCNA analysis showed that the turquoise module had a significant difference and high correlation coefficient. Then, the machine model was constructed and the results showed that the XGB model was the optimal model. The nomogram was constructed by using HDAC1, GPALPP1, LGALS3, SLC29A1, and RWDD3 five PRBMs. Finally, the datasets GSE32924 and GSE153007 verified the reliability of this result. CONCLUSIONS: The XGB model based on five PRBMs can be used for the accurate diagnosis of AD patients.

Inhibitory effects of isoliquiritin on an atopic dermatitis model through the CD177/JAK2/STAT pathway in vitro and in vivo.

Background: Atopic dermatitis (AD) is a complex inflammatory skin condition characterized by the proliferation and activation of immune cells in skin. Isoliquiritin (ISO) is an active component purified from Glycyrrhiza glabra. This study aimed to test the therapeutic potential of ISO for AD and verify its potential molecular mechanism. Methods: This study investigated the potential effects and possible underlying mechanisms of ISO against AD in vitro (HMC1.1 cells stimulated by phorbol-12-myristate-13-acetate and calcium ionophore A23187) and in vivo (AD-like mouse model induced by 1-chloro-2,4-dinitrochlorobenzene). Results: ISO dose-dependently suppressed the viability of HMC1.1 cells. ISO inhibited the secretion of the proinflammatory factors IL-6 and IL-8 and induced the apoptosis of HMC1.1 cells. ISO suppressed the phosphorylation of CD177, JAK2, STAT1, STAT3, and STAT5, and upregulated the protein expression of BAX and cleaved caspase-3 in vitro. ISO administration markedly diminished the infiltration of immune cells (mast cells, eosinophils) in cutaneous lesions. Simultaneously, ISO treatment alleviated the formation of skin lesions and affected other AD symptoms (thickness of the epidermis and dermis, ear edema, lymph node weight, spleen index, dermatitis score) but increased the thymus index in vivo, and downregulated expression of IL-4, IL-6, IgE, and thymic stromal lymphopoietin (TSLP). Conclusions: Collectively, our findings showed that ISO administration decreased skin lesion formation by inhibiting inflammation and enhancing immunomodulation through the CD177/JAK2/STAT signaling pathway.

RAS-association domain family 1A regulates the abnormal cell proliferation in psoriasis via inhibition of Yes-associated protein.

Psoriasis is a chronic, inflammatory skin disease with a high incidence and recurrence; however, its exact pathogenesis and aetiology remain unclear. This study aimed to analyse the effect of the upstream negative regulator RAS-association domain family 1A (RASSF1A) on Yes-associated protein (YAP) in psoriasis. Skin lesions of 22 patients with psoriasis and 19 healthy controls were used. Human epidermal keratinocytes stimulated by M5 (IL-1α, IL-17, IL-22, TNF-α and oncostatin M) were used to establish a psoriatic cell model. BALB/c mice treated with topical imiquimod were used to establish a psoriatic mouse model. As the methylation level of RASSF1A increased, its expression in psoriatic patients and mice model decreased. Addition of the methylation inhibitor 5-Aza-CdR or RASSF1A-overexpressing lentivirus vector increased RASSF1A and reduced YAP expression; meanwhile improved skin lesions, reduced cell proliferation, induced cell cycle arrest in the G0/G1 phase, increased apoptosis, reduced inflammatory cytokines and activities of ERK, STAT3 and NF-κB signalling pathways. The results indicated that RASSF1A could play a role in the treatment of psoriasis by inhibiting YAP expression. Based on these findings, targeted drugs that can inhibit the methylation or increase the expression of RASSF1A may be useful for treating psoriasis.

Role of YAP-related T cell imbalance and epidermal keratinocyte dysfunction in the pathogenesis of atopic dermatitis.

BACKGROUND: Atopic dermatitis (AD) is characterized by impaired skin barrier function and immune system dysfunction. The expression and role of Yes-associated protein (YAP) in AD are unclear. OBJECTIVE: To characterize the role of the YAP in T cell imbalance and epidermal keratinocyte dysfunction in the pathogenesis of AD. METHODS: We included 35 patients with AD (21 acute and 14 chronic). An AD mouse model was constructed using 2,4-dinitrofluorobenzene, and AD-like inflammatory cell model was constructed using TNF-α/IFN-γ-activated HaCaT cells. The proportion of Th1/Th2/Th17/Treg cells was detected using flow cytometry. After mononuclear cells were obtained from human peripheral blood or mouse spleen and induced to differentiate into different T cell subsets, YAP mRNA and protein expression were analyzed. Up-regulation of YAP was induced by lentivirus and down-regulation of YAP was induced by its specific inhibitor verteporfin (VP). The expression of YAP in skin lesions and infiltrating T cell subsets was detected using immunohistochemistry and double immunofluorescence staining, respectively. RESULTS: We found differing degrees of Th1/Th2/Th17/Treg imbalance in acute and chronic AD. YAP expression was downregulated in Treg cells and upregulated in Th17 cells; YAP expression was downregulated in the AD epidermis. After YAP overexpression, the proportion of both Th17 and the Treg cells differentiated from mouse spleen mononuclear cells increased. There was an opposite trend after YAP inhibition. The proliferation and migration decreased and apoptosis increased after YAP inhibition in HaCaT cells. CONCLUSION: Change of YAP expression may cause T cell imbalance and hamper the healing of the epidermis in AD.

Diversity analysis of gut microbiota between healthy controls and those with atopic dermatitis in a Chinese population.

An increasing body of evidence suggests that gut microbiota is involved in atopic dermatitis (AD). We aimed to use high-throughput sequencing to characterize the differences in the composition of the gut microbiota between healthy controls and patients with AD. Fecal samples from 93 volunteers were analyzed using 16S rRNA sequencing, including 44 patients with AD and 49 healthy control subjects, aged 6-22 years. Our data show that the operational taxonomic unit composition in patients with AD had greater component similarity than the healthy controls. Patients with AD had a lower alpha diversity than healthy control subjects. The relative abundance of Porphyromonadaceae, Blautia, Parabacteroides, Bacteroides ovatus, Bacteroides uniformis and Prevotella stercorea was significantly higher (P < 0.05) in patients with AD than healthy control subjects. Clostridium and P. stercorea were higher (P < 0.05) in healthy control subjects compared with patients with AD. The results of linear discriminant analysis effect size show that Bacteroidaceae and Porphyromonadaceae can act as possible biomarkers associated with diagnosis of AD. However, this needs further experimental verification. Taken together, these results demonstrate the changes in microbiota composition in AD compared with a healthy control group, opening the way to future diagnosis or intervention studies.

The formulae and biologically active ingredients of Chinese herbal medicines for the treatment of atopic dermatitis.

Atopic dermatitis (AD) is a common relapsing inflammatory skin disease characterized by severe pruritus that seriously affects the quality of patients' life. There is an increasingly large amount of research demonstrating that traditional Chinese medicine (TCM) including herbal formulae and bioactive ingredients exerts pharmacological effects on atopic dermatitis. It has been a long history of TCM being used to treat atopic dermatitis, especially in preventing disease recurrence, maintaining long-term remission, and reducing disease burden. Nowadays, both of TCM monomer preparations and traditional formulae are still widely used. This review focuses on TCM as well as its bioactive ingredients for the treatment of AD, from the perspectives of animal model construction, pharmacodynamic mechanisms and clinical studies of formulae. To be more specific, the regulation and molecular mechanisms of the herbal formulae and bioactive ingredients of TCM are investigated, and the latest clinical research on TCM formulae is discussed. Furthermore, it provides a summary of the strengths and utilities of TCM, and will be useful for doctors who use Chinese medicine for treatment or researchers who select candidates for clinical treatments or further high-quality clinical studies.

Mechanism of danshensu-induced inhibition of abnormal epidermal proliferation in psoriasis.

Psoriasis is a chronic, inflammatory skin disease with high incidence and high rates of relapse, for which no satisfactory treatments are currently available. Yes-associated protein (YAP) is highly expressed in psoriasis and may regulate the proliferation and apoptosis of keratinocytes. Danshen is a traditional Chinese medicine, commonly used in the treatment of psoriasis. Danshensu is the most abundant water-soluble component of Danshen, but its therapeutic mechanism is still unclear. In this study, MTT was used to detect the effects of different danshensu concentrations (0.125, 0.25, 0.5 mmol/l) on the proliferation of an M5-based psoriasis cell model. The effects of danshensu on cell cycle and apoptosis were detected by flow cytometry. Cyclins and apoptosis-related proteins were evaluated by Western blot. Danshensu (20, 40, 80 mg/kg/day) was administered intraperitoneally to the imiquimod (IMQ) psoriasis mouse model. After 7 days, the expression of YAP in the lesions was detected by immunohistochemistry and Western blot. We found that danshensu reduced the expression of YAP in the M5 psoriasis cell model, inhibited cell proliferation, induced cell cycle arrest in G0/G1 phase, and promoted cell apoptosis. All these effects were partly reverted by YAP overexpression. The skin lesions of IMQ mice were thinned and the scales reduced after intragastric administration of danshensu, which also resulted in dose-dependent inhibition of YAP expression. We concluded that danshensu prevents abnormal epidermis proliferation in psoriasis possibly by modulating YAP expression. Our work can provide a theoretical basis for the clinical application of Danshen in the treatment of psoriasis.

Therapeutic Effects of Chinese Herbal Formula (PTQX) on NC/Nga Mice with Atopic Dermatitis-Like Skin Lesions.

Atopic dermatitis (AD), also known as atopic eczema, is a chronic pruritic inflammatory skin disease. The available systemic therapies for atopic dermatitis are inadequate. Objective. This study aimed to evaluate the effects of the Chinese herbal formula Pei Tu Qing Xin (PTQX) on dermatitis severity and ear swelling, immunomodulation, and the infiltration of mast cells in a mouse model of 1-chloro-2,4-dinitrobenzene- (DNCB-) induced AD. Methods. AD-like symptoms were induced by DNCB in NC/Nga mice. Skin lesions, dermatitis, ear swelling, and scratching behaviour were evaluated. Changes in the T-helper type 1 (Th1), Th2, Th17, and regulatory T (Treg) subtypes and immunoregulation in the spleen and lymph nodes were detected by flow cytometry. Results. Histopathological and immunohistochemical analyses demonstrated that PTQX decreased the DNCB-mediated induction of mast cells and infiltration of inflammatory cells in the ear and dorsal skin. PTQX also reduced the DNCB-induced increase in the serum immunoglobulin E level, pruritus, and dermatitis (red, flaky areas) on the dorsal skin. Furthermore, PTQX regulated the balance between the populations of Th1, Th2, Th17, and Treg cells (particularly the latter two) in the lymph nodes. Conclusions. Our results suggest that the Chinese herbal formula PTQX can alleviate symptoms of AD, such as epithelial damage, redness, swelling, and pruritus, and potentially be used to treat this condition.

Factors Influencing Atopic Dermatitis Incidence in Offspring.

Atopic dermatitis (AD) is a chronic, recurrent skin condition resulting from both genetic and environmental factors. In recent decades, the prevalence of AD has increased considerably in some countries. However, given that the role of genetics is unlikely to have changed over this short period, the increased prevalence is more likely to be explained by changes in environmental and maternal factors. The aim of this review is to comprehensively summarize the various factors impacting AD incidence in offspring and provide guidance for primary prevention. Recent research has demonstrated that environmental and climate factors, maternal history of allergies, gestational diabetes, and stress play essential roles in increasing the risk of AD in infants. Some factors have protective effects against the incidence of AD, including probiotic supplementation, fish intake, and moisturizers. This review also considers fundamental research into AD prevalence and factors that in the past were mistakenly thought to affect that prevalence, such as caesarean section and antigen avoidance. The potential influence of these factors on infant AD incidence remains inconclusive and needs further study. Furthermore, infants with a family history of atopic disease may benefit from early weaning or reduced breastfeeding duration.

MicroRNA­146a as a potential regulator involved in the pathogenesis of atopic dermatitis.

Previous studies have demonstrated that microRNA (miR)­146a is involved in the inflammatory response of atopic dermatitis (AD). The aim of the present study was to investigate the expression of miR­146a in the serum of patients with AD and in skin lesions of AD animal models. In addition, we aimed to predict and verify the target genes of miR­146a. miR­146a expression was measured in AD patient serum via reverse transcription­quantitative PCR. T­helper (Th)1 [CD4+; interferon (IFN)­Î³+] and Th2 [CD4+; interleukin (IL)­4+] expression in peripheral blood mononuclear cells was evaluated using flow cytometry. Following the establishment of a 2,4­dinitrofluorobenzene­induced C57BL/6 mouse AD model, Th1 (CD4+IFN­Î³+) and Th2 (CD4+IL­4+) expression was analyzed in murine spleen cells via flow cytometry. Plasmids were transfected into 293T cells and at 48 h post­transfection, cells were analyzed using a luciferase assay system. The results revealed that the AD group had a significantly lower Th1/Th2 ratio and a significantly higher miR­146a expression compared with the control group (P<0.05). Furthermore, a decreased Th1/Th2 ratio and a significantly increased miR­146a expression were observed in the model group compared with the control group (P<0.01). We also conducted a dual­luciferase assay to determine whether small ubiquitin­related modifier 1 (SUMO1) if the target gene of miR­146a. We observed a ~30% decrease in the relative luciferase activity in cells containing the 3'­untranslated region of SUMO1 + miR­146a). The results of the luciferase assay indicated that may be a direct mRNA target of miR­146a; however, the quantification of band density of SUMO1 expression following western blotting did not significantly differ. The development of animal models in AD research is of vital importance. The results revealed that miR­146a may be a potential regulator involved in the pathogenesis of AD. Furthermore, the current study determined that miR­146a could be a valuable marker of AD and thus, may be applied in the development of therapeutic strategies for treating AD.

Hepatoprotective Effect of Jianpi Huoxue Formula on Nonalcoholic Fatty Liver Disease Induced by Methionine-Choline-Deficient Diet in Rat.

In parallel with the prevalence metabolic syndrome, nonalcoholic fatty liver disease (NAFLD) has become the most common chronic liver disease in most countries. It features a constellation of simple steatosis, nonalcoholic steatohepatitis (NASH), fibrosis, cirrhosis, and even hepatocellular carcinoma. There are no approved drugs for effective management of NAFLD and NASH. Jianpi Huoxue formula (JPHX) mainly consists of Atractylodes macrocephal (Baizhu), Salvia miltiorrhiza (Danshen), Rasux Paeonia Alba (Baishao), Rhizoma Alismatis (Zexie), and Fructus Schisandrae Chinensis (Wuweizi), which may have beneficial effects on NAFLD. The aim of the study was to identify the effect of JPHX on NAFLD. A NAFLD model was induced by methionine-choline-deficient food (MCD) in Wistar rats and orally administered with simultaneous JPHX, once a day for 8 weeks. Hepatocellular injury, lipid profile, inflammation, fibrosis, and apoptosis were evaluated. The results showed that JPHX significantly decreased the abnormal serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels compared with the MCD model (P<0.05). Furthermore, JPHX protected MCD diet-fed rats from accumulation of hepatic triglycerides (TG) and total cholesterol (TC). Histological examination demonstrated that JPHX noticeably normalized the NAFLD activity score (NAS). Moreover, JPHX ameliorated liver inflammation by decreasing TNF-α levels and reduced collagen and matrix metalloproteinases in MCD diet-fed rats. In addition, JPHX prevented rats from MCD-induced cellular apoptosis, as suggested by TUNEL staining, and suppressed the activation of caspase 3 and 7 proteins. JPHX also inhibited the phosphorylation of JNK. In conclusion, JPHX exhibited a hepatoprotective effect against NAFLD in an MCD experimental model.

The first case report of kerion-type scalp mycosis caused by Aspergillus protuberus.

BACKGROUND: Scalp mycosis is often caused by dermatophytes and was so called tinea capitis. There is no published report caused by Aspergillus protuberus. We report a rare case of kerion-type scalp mycosis caused by A. protuberus. CASE PRESENTATION: A 5-year-old girl developed pyogenic mass with pain for 8 days and got a fever for 2 days prior to admission. Surgical incision and drainage of the mass, intravenous cefuroxime and metronidazole in the local hospital aggravated the skin lesions. Species identification was performed by observation of morphologic and biochemical characteristicsand sequencing of the internal transcribed spacer (ITS) and ß-tubulin (BT2). Treatment with oral and topical antifungal agents was effective with no relapse during the six months of clinical follow-up. CONCLUSIONS: Aspergillusis a opportunistic pathogenic fungus and its infection occurs mostly in patients with underlying conditions and immunocompromised statuses. So far no report of kerion-type scalp infection has been reported. The first case of kerion-type scalp mycosis caused by A. protuberus was described to highlight the importance of mycological examination that helps to recognize rare pathogenic fungi. Any boggy lesion with hair loss over the scalp and non-responsive to antibiotics should be suspected as resulting from fungal infection, and mycological examination should be performed, especially in children.

Protective effect of forsythoside B against lipopolysaccharide-induced acute lung injury by attenuating the TLR4/NF-κB pathway.

Acute lung injury (ALI), which is mainly triggered by infection, pneumonia, vasculitis, and sepsis, has no specific and effective therapy except for primary supportive treatment or bedside care. Excessive inflammation caused by innate immune cells is the major characteristic of ALI. Forsythoside B, a phenylethanoside compound, possesses good antioxidant and anti-bacterial properties in vivo and in vitro. In this study, the therapeutic potential of forsythoside B and its mechanism of action were investigated in a lipopolysaccharide (LPS)-induced ALI mouse model. The results showed that LPS-induced edema exudation and lung pathological changes in mice were significantly suppressed by forsythoside B pre-treatment. Furthermore, it also attenuated lung inflammation caused by LPS stimulation, evidenced by decreased inflammatory cell infiltration and down-regulated expression of cytokines, chemokines, and inducible enzymes. The anti-inflammation property of forsythoside B was confirmed in vitro using LPS-stimulated RAW 264.7 macrophages. Moreover, it alleviated LPS-induced inflammation by inhibiting the activation of TLR4/NF-κB signaling pathway in vivo and in vitro. In conclusion, the results demonstrated that forsythoside B protects against LPS-induced ALI by attenuating inflammatory cell infiltration and suppressing TLR4/NF-κB-mediated lung inflammation. Therefore, it might be a potential therapeutic agent for ALI caused by sepsis.

Improvement of glucocorticoid-impaired thymus function by dihydromyricetin via up-regulation of PPARγ-associated fatty acid metabolism.

T lymphocytes produced by the thymus are essential mediators of immunity. Accelerated thymic atrophy appears in the patients with administration of glucocorticoids (GCs) which are commonly-used drugs to treat autoimmune and infectious diseases, leading to dysregulation of immunity with manifestation of progressive diminution of new T cell production. However, there is no ideal method to overcome such side effects of GCs. In the current study, we proposed a composition of dexamethasone (DEX) and dihydromyricetin (DMY) derived from a medicinal plant, which could protect from DEX-induced thymus damage and simultaneously enhance the anti-inflammatory effect of DEX. In the current study, we found that DEX-damaged thymic cellularity and architecture, reduced thymocyte numbers, induced thymocyte apoptosis and dropped CD4+ and CD8+ double positive T cell numbers in thymus which was effectively improved by co-treatment with DMY. Quantification of signal joint TCR delta excision circles (TRECs) and Vß TCR spectratyping analysis were employed to determine the thymus function with indicated treatments. The results showed that DEX-impaired thymus output and decreased TCR cell diversity which was ameliorated by co-treatment with DMY. iTRAQ 2D LC-MS/MS was applied to analyze the proteomic profiling of thymus of mice treated with or without indicated agents, followed by informatics analysis to identify the correlated signaling pathway. After validated by Western blotting and Real-time PCR, we found that PPARγ-associated fatty acid metabolism was increased in the thymic tissues of the animals treated with DMY plus DEX than the animals treated with DEX alone. The agonist and antagonist of PPARγ were further employed to verify the role of PPARγ in the present study. Furthermore, DMY demonstrated a synergistic effect with co-administration of DEX on suppressing inflammation in vivo. Collectively, DMY relieved thymus function damaged by DEX via regulation of PPARγ-associated fatty acid metabolism. Our findings may provide a new strategy on protection of thymus from damage caused by GCs by using appropriate adjuvant natural agents through up-regulation of PPARγ-associated fatty acid metabolism.

Thymic function in the regulation of T cells, and molecular mechanisms underlying the modulation of cytokines and stress signaling (Review).

The thymus is critical in establishing and maintaining the appropriate microenvironment for promoting the development and selection of T cells. The function and structure of the thymus gland has been extensively studied, particularly as the thymus serves an important physiological role in the lymphatic system. Numerous studies have investigated the morphological features of thymic involution. Recently, research attention has increasingly been focused on thymic proteins as targets for drug intervention. Omics approaches have yielded novel insights into the thymus and possible drug targets. The present review addresses the signaling and transcriptional functions of the thymus, including the molecular mechanisms underlying the regulatory functions of T cells and their role in the immune system. In addition, the levels of cytokines secreted in the thymus have a significant effect on thymic functions, including thymocyte migration and development, thymic atrophy and thymic recovery. Furthermore, the regulation and molecular mechanisms of stress­mediated thymic atrophy and involution were investigated, with particular emphasis on thymic function as a potential target for drug development and discovery using proteomics.

Isoliquiritigenin suppresses human T Lymphocyte activation via covalently binding cysteine 46 of IκB kinase.

The efficacious practice of precision personalized medicine requires a more exact understanding of the molecular mechanisms of drug, hence then it is necessary to identify the binding site of the drugs derived from natural sources. In the study, we investigated the suppressive effect and underlying mechanism of isoliquiritigenin (2',4',4-trihydroxychalcone; ILG), a phyto-flavonoid, on human T lymphocyte activation in vitro and in vivo. The results showed that ILG dose-dependently suppressed human T cell activation via suppressing IκBα phosphorylation and degradation, NF-κB nuclear translocation and IKKß activity. Molecular docking results predicted that cysteine 46 (Cys-46) is probably the binding site of ILG on IKKß, and this prediction has been validated by competition assay and kinase assay. To further verify the binding site of this compound in vivo, IKKßC46A transgenic (IKKßC46A) mice were generated. We found that ILG had a less potent immune-suppressive effect in homozygous IKKßC46A mice than IKKß wild type (IKKß wt) littermates with the delay-type hypersensitivity (DTH), suggesting that ILG cannot significantly suppress the inflammation due to the mutation of Cys-46 in the transgenic mice. Collectively, our findings indicate that the ILG inhibited T cell activation in vivo and in vitro via directly binding to IKKß Cys46.

Shikonin Suppresses Human T Lymphocyte Activation through Inhibition of IKK ß Activity and JNK Phosphorylation.

The key role of T cells has been elaborated in mediating immune responses and pathogenesis of human inflammatory and autoimmune conditions. In the current study the effect of shikonin, a compound isolated from a medicinal plant, on inhibition of T-cell activation was firstly examined by using primary human T lymphocytes isolated from buffy coat. Results showed that shikonin dose dependently suppressed T-cell proliferation, IL-2 and IFN- γ secretion, CD69 and CD25 expression, as well as cell cycle arrest activated by costimulation of PMA/ionomycin or OKT-3/CD28 monoclonal antibodies. Moreover, these inhibitory responses mediated by shikonin were found to be associated with suppression of the NF- κ B signaling pathway via inhibition of the IKK α / ß phosphorylation, I κ B- α phosphorylation and degradation, and NF- κ B nuclear translocation by directly decreasing IKK ß activity. Moreover, shikonin suppressed JNK phosphorylation in the MAPKs pathway of T cells. In this connection, we conclude that shikonin could suppress T lymphocyte activation through suppressing IKK ß activity and JNK signaling, which suggests that shikonin is valuable for further investigation as a potential immunosuppressive agent.

Gambogenic acid induced mitochondrial-dependent apoptosis and referred to phospho-Erk1/2 and phospho-p38 MAPK in human hepatoma HepG2 cells.

Gambogenic acid, identified from Gamboge, is responsible for anti-tumor effects, and has been shown to be a potential molecule against human cancers. In this study, the molecular mechanism of gambogenic acid-induced apoptosis in HepG2 cells was investigated. Gambogenic acid significantly inhibited cell proliferation and induced apoptosis. Acridine orange/ethidium bromide (AO/EB) staining was used to observe apoptosis, and then confirmed by transmission electron microscopy. Gambogenic acid induced apoptosis and morphological changes in mitochondria, and intracellular reactive oxygen species (ROS) and mitochondrial membrane permeabilization (MMP) in mitochondrial apoptosis pathway were also examined. Results showed that the levels of phospho-p38 and its downstream phospho-Erk1/2 of HepG2 cells increased in time- and concentration-dependent manners after gambogenic acid treatments. Additionally, gambogenic acid increased expression ratio of Bcl-2/Bax in mRNA levels, Western blotting analysis also further confirmed the reduced level of Bcl-2 and increase the expression level of Bax in HepG2 cells. These results indicated that gambogenic acid induced mitochondrial oxidative stress and activated caspases through a caspase-3 and caspase-9-dependent apoptosis pathway. Moreover, gambogenic acid mediated apoptosis and was involved in the phospho-Erk1/2 and phospho-p38 MAPK proteins expression changes in HepG2 cells.