ABSTRACT
Accumulating evidence suggests that polycyclic aromatic hydrocarbons (PAH) which adsorbed on the surface of ambient air particulate matters (PM), are the major toxic compound to cause cardiovascular and respiratory diseases, even cancer. However, its detrimental effects on human skin cell remain unclear. Here, we demonstrated that SRM1649b, a reference urban dust material of PAH, triggers human skin cells aging through cell cycle arrest, cell growth inhibition and apoptosis. Principally, SRM1649b facilitated Aryl hydrocarbon receptor (AhR) translocated into nucleus, subsequently activated ERK/MAPK signaling pathway, and upregulated aging-related genes expression. Most important, we found that AhR antagonist efficiently revert the aging of skin cells. Thus our novel findings firstly revealed the mechanism of skin aging under PAH contamination and provided potential strategy for clinical application.
Subject(s)
Keratinocytes/drug effects , Polycyclic Aromatic Hydrocarbons/pharmacology , Receptors, Aryl Hydrocarbon/antagonists & inhibitors , Skin Aging/drug effects , Apoptosis/drug effects , Cell Cycle Checkpoints/drug effects , Cell Proliferation/drug effects , Cells, Cultured , Dose-Response Relationship, Drug , Humans , Polycyclic Aromatic Hydrocarbons/chemistry , Receptors, Aryl Hydrocarbon/metabolism , Structure-Activity RelationshipABSTRACT
Interleukin (IL)-33 is a novel member of the IL-1 superfamily of cytokines that has recently become a focal point for research into the pathogenesis of atopic dermatitis (AD). However, the expression and regulation of IL-33 in human epidermal keratinocytes have not well been delineated. The aim of this study was to evaluate IL-33 and its receptor ST2L expression in skin lesions of AD patients and explored the signal transduction mechanisms leading to the IL-33 expression and of the IL-33's pharmacological action in keratinocytes from AD patients (ADKs) and those from healthy controls (NHEKs). We performed immunocytochemistry, reverse transcription-polymerase chain reaction, Western blotting, and enzyme-linked immunosorbent assay to investigate ADKs compared with NHEKs. We found that IL-33/ST2L were positively expressed in the skin lesions of AD patients and a high expression of IL-33 was induced in keratinocytes by IL-4 plus interferon [IFN]-γ or IFN-γ alone at the mRNA and protein levels. Meanwhile, IFN-γ induced IL-33 expression through extracellular signal-regulated kinase (ERK), p38 mitogen-activated protein kinase (MAPK), epidermal growth factor receptor (EGFR), and Janus kinase/signal transducer and activator of transcription. The expression of ST2L was increased in a time- and dose-dependent manner in both types of cells incubated with IL-33, and was especially increased in ADKs compared with NHEKs. We examined the cytokine IL-6 and the chemokines CXCL-8/IL-8, CCL-20, CCL-17, CCL-5, and CCL-2 in keratinocytes, which showed increased expression in a time- and dose-dependent manner in ADKs when induced by IL-33. Furthermore, 4 signaling pathways (ERK, p38 MAPK, c-Jun N-terminal kinase, and nuclear factor-κB) were involved in the IL-33-mediated induction in both cells. In conclusion, IL-33 is closely interlinked in AD skins and keratinocytes. IL-33 plays an important role in the pathogenesis of immune inflammatory responses in AD, which might be a possible therapeutic target in the treatment of AD.
Subject(s)
Epidermis/metabolism , Gene Expression Regulation , Interleukin-33/genetics , Interleukin-33/metabolism , Keratinocytes/metabolism , Chemokines/metabolism , Cytokines/genetics , Cytokines/metabolism , Dermatitis, Atopic/genetics , Dermatitis, Atopic/metabolism , Dermatitis, Atopic/pathology , Humans , Inflammation Mediators/metabolism , Interferon-gamma/metabolism , Interferon-gamma/pharmacology , Interleukin-1 Receptor-Like 1 Protein/genetics , Interleukin-1 Receptor-Like 1 Protein/metabolism , Mitogen-Activated Protein Kinases/metabolism , NF-kappa B/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Signal Transduction/drug effectsABSTRACT
The aim of this study was to prepare a liposomal delivery system for rapamycin and study its in vitro release characteristics. The results may provide a foundation for the further development of a liposomal delivery system for rapamycin and the establishment of a new active treatment method targeted towards the cellular components of atherosclerotic plaques. The ethanol injection method was used to prepare rapamycin-containing liposomes. The formulation was optimized by orthogonal design, and the degree of rapamycin release by the liposomes was measured by the reverse dialysis method. Orthogonal testing showed that the optimum formulation had a phospholipid concentration of 4%, a phospholipid-cholesterol mass ratio of 8:1, a drug-lipid mass ratio of 1:20 and an aqueous phase pH of 7.4. Rapamycin-containing liposomes with an encapsulation efficiency of 82.11±2.13% were prepared, and the in vitro release of rapamycin from the liposomes complied with a first-order kinetic equation. In conclusion, the formulation was optimized, the prepared liposomes had a high rapamycin encapsulation rate and good reproducibility, and their in vitro release had a certain delayed-release effect.
