Vitamin D attenuates DNCB-induced atopic dermatitis-like skin lesions by inhibiting immune response and restoring skin barrier function

Ferulic acid protects against stress-induced myocardial injury in mice

Excessive stress is a known contributor to cardiovascular diseases (CVD), and ferulic acid (FA), a natural phenolic compound, has demonstrated significant antioxidant and anti-inflammatory properties. This study investigates the protective effects of FA against stress-induced myocardial injury (SIMI) and elucidates the underlying mechanisms. An acute SIMI model was established in mice using low-temperature water immersion restraint. Cardiac function was assessed via cardiac index and histopathological analysis. Serum levels of corticosterone (CORT), lactate dehydrogenase (LDH), and brain natriuretic peptide (BNP) were quantified using enzyme-linked immunosorbent assay (ELISA), along with inflammatory markers TNF-α and IL-1β. The oxidative stress parameters, including malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD), and reactive oxygen species (ROS), were analyzed using colorimetric methods and fluorescent probes. Immunohistochemistry (IHC) and Western Blot were used to analyze the expression of proteins related to TNF, MAPK, PPAR-α/PGC-1α, and Nrf2 signaling pathways. Results indicated that FA pretreatment improved cardiac index, myocardial structural integrity, and reduced inflammatory cell infiltration. Serum levels of LDH, BNP, CORT, TNF-α, and IL-1β were significantly decreased in FA-treated SIMI mice. Elevated MDA and ROS levels, along with decreased GSH and SOD levels in the SIMI group, were reversed by FA pretreatment, likely through activation of the PPARα/PGC-1α and Nrf2 signaling pathways. Additionally, FA inhibited the TNF-α/TNFR1 and ERK/JNK MAPK pathways, contributing to its protective effects. In conclusion, FA mitigates SIMI by alleviating oxidative stress and inflammatory responses.

Tissue-Specific Metabolic Reprogramming in Innate Lymphoid Cells and Its Impact on Disease

Recent advances have highlighted the crucial role of metabolic reprogramming in shaping the functions of innate lymphoid cells (ILCs), which are vital for tissue immunity and homeostasis. As tissue-resident cells, ILCs dynamically respond to local environmental cues, with tissue-derived metabolites such as short-chain fatty acids and amino acids directly modulating their effector functions. The metabolic states of ILC subsets-ILC1, ILC2, and ILC3-are closely linked to their ability to produce cytokines, sustain survival, and drive proliferation. This review provides a comprehensive analysis of how key metabolic pathways, including glycolysis, oxidative phosphorylation, and fatty acid oxidation, influence ILC activation and function. Furthermore, we explore the complex interactions between these metabolic pathways and tissue-specific metabolites, which can shape ILC-mediated immune responses in health and disease. Understanding these interactions reveals new insights into the pathogenesis of conditions such as asthma, inflammatory bowel disease, and cancer. A deeper understanding of these mechanisms may not only advance our knowledge of disease pathogenesis but also lead to the development of novel therapeutic strategies targeting metabolic pathways in ILCs to treat tissue-specific immune disorders.

The changes of intestinal flora and metabolites in atopic dermatitis mice

Introduction

Atopic dermatitis (AD) is an allergic disease caused by various factors that can affect an individual's appearance and cause psychological stress. Therefore, it is necessary to investigate the underlying mechanisms and develop effective treatment strategies. The gut microbiota and bacterial metabolism play crucial roles in human diseases. However, their specific role in AD remains unclear.

Methods

In this study, we established a mouse model of AD and found that 2,4-dinitrofluorobenzene disrupted the skin barrier in mice. The species composition of intestinal bacteria was then analyzed by fecal 16s rRNA sequencing. The metabolic level of mice was analyzed by untargeted and targeted metabolomics in stool.

Results

The levels of filaggrin and aquaporin 3 proteins in the model mice and total superoxide dismutase, catalase and malondialdehyde levels were significantly altered. Additionally, inflammatory factors such as tumor necrosis factor-alpha showed a significant increase. Using 16S rRNA gene sequencing, we identified 270 bacterial species with altered abundances of Ruminococcaceae and Bifidobacteriaceae. The untargeted metabolomic analysis detected 1,299 metabolites. Targeted analysis of free fatty acids revealed 49 metabolites with notable increases in linoleic and linolenic acid levels. Fecal bacterial transplantation experiments have demonstrated that oxidative stress, inflammation, and skin barrier damage were alleviated after transplantation.

Discussion

These findings suggested that the metabolite linoleic acid negatively correlated with Ruminococcaceae and Bifidobacteriaceae may influence AD development. Perturbations in the intestinal bacteria and flora contributed to the development of AD, and the mouse model could serve as a valuable tool for further investigation of therapeutic approaches for managing ADS.

Effects of Huang-Lian-Jie-Du decoction on improving skin barrier function and modulating T helper cell differentiation in 1-chloro-2,4-dinitrobenzene-induced atopic dermatitis mice

Background: Atopic dermatitis (AD) is among the most frequently encountered skin diseases, bothering a considerable number of patients. Today, corticosteroids and antihistamines are among the numerous drugs applied for the therapy of AD. However, lengthy use of them contributes to side effects, such as physiological changes in skin. As an alternative and supplementary therapy, traditional Chinese medicine has become a trend for AD treatment. Huang-Lian-Jie-Du decoction (HLJDD), a renowned herbal formula has been employed to treat inflammatory diseases such as AD. However, its role in regulating immunity in AD remains unclear. The object of this study was to elucidate the efficacy of HLJDD and reveal the implicit mechanism from an immunological perspective in AD-like mice. Methods: In brief, 1-chloro-2,4-dinitrobenzene (DNCB) for the sensitization phase (1% DNCB) and stimulation phase (1.5% DNCB) were applied for BALB/c mice. HLJDD and dexamethasone (DXMS) were administered orally to the mice. Mice skin and spleens were collected to evaluate the efficacy of HLJDD. 16S rRNA sequencing was applied to evaluate the commensal microbiota changes in skin and fecal. In vitro, spleen CD4+ T cells and bone marrow-derived mast cells (BMMCs) were co-cultured to explore the modulation of HLJDD in T helper (Th) cells phenotyping. Results: HLJDD showcased a substantial amelioration in skin through the upregulation of FLG, LOR, AQP3, and reducing scratching behaviors in AD-like mice, Also, the quantity of infiltrated mast cells (MCs), pruritus-related mRNA were decreased. In addition, the expression of OX40/OX40L was decreased by HLJDD, which was critical in Th-cell phenotyping. With the treatment of HLJDD, Th1/Th2 and Th17/Treg ratios in AD-like mice became balanced. The structure of commensal microbiota in AD-like mice was affected by HLJDD. HLJDD could also improve the imbalance of Th17/Treg in vitro. Conclusion: HLJDD could improve the symptoms of AD-like mice by alleviating the scratching behaviors via decreased Th2 and pruritus-related mRNA expression. HLJDD also enhanced the relative diversity of skin microbiota and changed the structure of intestinal microbiota. An in-depth study found that HLJDD could balance the ratio of Th1/Th2, Th17/Treg in AD-like mice, and Th17/Treg in vitro by regulating the OX40/OX40L signaling pathway.

Air pollution and skin diseases: A comprehensive evaluation of the associated mechanism

Air pollutants deteriorate the survival environment and endanger human health around the world. A large number of studies have confirmed that air pollution jeopardizes multiple organs, such as the cardiovascular, respiratory, and central nervous systems. Skin is the largest organ and the first barrier that protects us from the outside world. Air pollutants such as particulate matter (PM), polycyclic aromatic hydrocarbons (PAHs), volatile organic compounds (VOCs) will affect the structure and function of the skin and bring about the development of inflammatory skin diseases (atopic dermatitis (AD), psoriasis), skin accessory diseases (acne, alopecia), auto-immune skin diseases (cutaneous lupus erythematosus(CLE) scleroderma), and even skin tumors (melanoma, basal cell carcinoma (BCC), squamous-cell carcinoma (SCC)). Oxidative stress, skin barrier damage, microbiome dysbiosis, and skin inflammation are the pathogenesis of air pollution stimulation. In this review, we summarize the current evidence on the effects of air pollution on skin diseases and possible mechanisms to provide strategies for future research.

Nuclear receptors for epidermal lipid barrier: Advances in mechanisms and applications

The skin plays an essential role in preventing the entry of external environmental threats and the loss of internal substances, depending on the epidermal permeability barrier. Nuclear receptors (NRs), present in various tissues and organs including full-thickness skin, have been demonstrated to exert significant effects on the epidermal lipid barrier. Formation of the lipid lamellar membrane and the normal proliferation and differentiation of keratinocytes (KCs) are crucial for the development of the epidermal permeability barrier and is regulated by specific NRs such as PPAR, LXR, VDR, RAR/RXR, AHR, PXR and FXR. These receptors play a key role in regulating KC differentiation and the entire process of epidermal lipid synthesis, processing and secretion. Lipids derived from sebaceous glands are influenced by NRs as well and participate in regulation of the epidermal lipid barrier. Furthermore, intricate interplay exists between these receptors. Disturbance of barrier function leads to a range of diseases, including psoriasis, atopic dermatitis and acne. Targeting these NRs with agonists or antagonists modulate pathways involved in lipid synthesis and cell differentiation, suggesting potential therapeutic approaches for dermatosis associated with barrier damage. This review focuses on the regulatory role of NRs in the maintenance and processing of the epidermal lipid barrier through their effects on skin lipid synthesis and KC differentiation, providing novel insights for drug targets to facilitate precision medicine strategies.