ABSTRACT
The beneficial effects of certain herbal medicines on cutaneous function have been appreciated for centuries. Among these agents, chrysanthemum extract, apigenin, has been used for skin care, particularly in China, for millennia. However, the underlying mechanisms by which apigenin benefits the skin are not known. In this study, we first determined whether topical apigenin positively influences permeability barrier homoeostasis, and then the basis thereof. Hairless mice were treated topically with either 0.1% apigenin or vehicle alone twice daily for 9 days. At the end of the treatments, permeability barrier function was assessed with either an electrolytic water analyzer or a Tewameter. Our results show that topical apigenin significantly enhanced permeability barrier homoeostasis after tape stripping, although basal permeability barrier function remained unchanged. Improved barrier function correlated with enhanced filaggrin expression and lamellar body production, which was paralleled by elevated mRNA levels for the epidermal ABCA12. The mRNA levels for key lipid synthetic enzymes also were upregulated by apigenin. Finally, both cathelicidin-related peptide and mouse beta-defensin 3 immunostaining were increased by apigenin. We conclude that topical apigenin improves epidermal permeability barrier function by stimulating epidermal differentiation, lipid synthesis and secretion, as well as cutaneous antimicrobial peptide production. Apigenin could be useful for the prevention and treatment of skin disorders characterized by permeability barrier dysfunction, associated with reduced filaggrin levels and impaired antimicrobial defenses, such as atopic dermatitis.
Subject(s)
Apigenin/administration & dosage , Apigenin/pharmacology , Cell Membrane Permeability/drug effects , Epidermis/physiology , Homeostasis/drug effects , Plant Extracts/administration & dosage , Plant Extracts/pharmacology , ATP-Binding Cassette Transporters/metabolism , Administration, Topical , Animals , Antimicrobial Cationic Peptides/metabolism , Cell Differentiation/drug effects , Cell Differentiation/physiology , Cell Membrane Permeability/physiology , Cells, Cultured , Chrysanthemum , Dose-Response Relationship, Drug , Epidermal Cells , Epidermis/drug effects , Female , Filaggrin Proteins , Homeostasis/physiology , Intermediate Filament Proteins/metabolism , Keratinocytes/cytology , Keratinocytes/drug effects , Keratinocytes/metabolism , Mice , Mice, Hairless , Models, Animal , Skin/cytology , Skin/drug effects , Skin/metabolism , beta-Defensins/metabolism , CathelicidinsABSTRACT
Orange peel extract appears to exhibit beneficial effects on skin whitening, inflammation, UVB protection, as well as keratinocyte proliferation. In the present study, we determine whether topical hesperidin influences epidermal permeability barrier function and its underlying mechanisms. Hairless mice were treated topically with 2% hesperidin or 70% ethanol alone twice daily for 6 days. At the end of treatment, basal transepidermal water loss (TEWL) was measured 2 and 4 h post barrier disruption. Epidermal proliferation and differentiation were evaluated by immunohistochemical staining and Western blot analysis. Additionally, lamellar body density and secretion were assessed by electron microscopy. Although there were no significant differences in basal barrier function, in comparison with control animals, topical hesperidin significantly accelerated barrier recovery at both 2 and 4 h after acute barrier abrogation. Enhanced barrier function in hesperidin-treated skin correlated with stimulation of both epidermal proliferation and differentiation, as well as enhanced lamellar body secretion. These results indicate that topical hesperidin enhances epidermal permeability barrier homeostasis at least in part due to stimulation of epidermal proliferation, differentiation, as well as lamellar body secretion.
Subject(s)
Cell Differentiation/drug effects , Cell Membrane Permeability/drug effects , Epidermal Cells , Hesperidin/administration & dosage , Hesperidin/pharmacology , Administration, Topical , Animals , Biopsy , Cell Differentiation/physiology , Cell Membrane Permeability/physiology , Cell Proliferation/drug effects , Dose-Response Relationship, Drug , Epidermis/physiology , Epidermis/ultrastructure , Female , Homeostasis/drug effects , Homeostasis/physiology , Mice , Mice, Hairless , Models, AnimalABSTRACT
We report a case of cutaneous silica granuloma with generalized involvement of distal lymph nodes; no similar case has been reported in the published work. The 45-year-old man was a stonemason who had been incidentally sprayed with rock dust from a saw 22 years ago. The subject presented with nodules and erythematous areas on his face and chin. In addition, there was swelling in the cervical and inguinal lymph nodes. An excised lymph node had normal architecture with numerous non-caseating epithelioid cell granuloma and silicotic nodules which contained scattered, multinucleated, giant cells. There were particles in the granuloma exhibiting birefringence under polarized light microscopy. Elemental X-ray spectra of these lesions showed the presence of silica in these granulomas.
