Keratinocyte migration during re-epithelization is crucial in wound healing under biochemical and biomechanical microenvironment. However, little is known about the underlying mechanisms whereby mechanical tension and cocultured fibroblasts or keratinocytes modulate the migration of keratinocytes or fibroblasts. Here we applied a tensile device together with a modified transwell assay to determ...

Biomaterial scaffolds are categorized into artificial or natural polymers, or combinations of the two. Artificial polymers often undergo serum protein adsorption, elicit foreign body and encapsulation immune responses post-implantation. Large pore bovine electrospun collagen I was therefore screened as a candidate for human keratinocyte and fibroblast cell scaffolds. Human HaCaT keratinocyte an...

Licorice (Glycyrrhiza) species have been widely used as a traditional medicine and a natural sweetener in foods. The 18β-glycyrrhetinic acid (18β-GA) is a bioactive compound in licorice that exhibits potential anti-cancer, anti-inflammatory, and anti-microbial activities. Many synthesized derivatives of 18β-GA have been reported to be cytotoxic and suggested for the treatment of malignant disea...

The insulin-like growth factor (IGF) system plays an important role in skin. HaCaT human keratinocytes proliferate in response to IGFs and synthesize IGF-binding protein-3 (IGFBP-3). Recently, IGFBP-6 was also identified by NH2-terminal sequencing, but it has not been identified by Western ligand blotting. In the present study, IGFBP-6 was detected in HaCaT-conditioned medium by use of immunobl...

Malic acid (MA) has been commonly used in cosmetic products, but the safety reports in skin are sparse. To investigate the biological effects of MA in human skin keratinocytes, we investigated the potential cytotoxicity and apoptotic effects of MA in human keratinocyte cell lines (HaCaT). The data showed that MA induced apoptosis based on the observations of DAPI staining, DNA fragmentation, an...

In this study, we investigated the protective effects of processed Panax ginseng, sun ginseng (SG) against the UVB-irradiation on epidermal keratinocytes and dermal fibroblasts. Pretreatment of SG in HaCaT keratinocytes and human dermal fibroblasts reduced UVB-induced cell damage as seen by reduced lactate dehydrogenase release. We also found that SG restored the UVB-induced decrease in anti-ap...

Protein kinase Cζ (PKCζ) is a member of the atypical protein kinase C family. Its roles in macrophages or skin-resident keratinocytes have not been fully evaluated. In this study, we provide evidence that PKCζ mediates lipopolysaccharide (LPS)-induced tumor necrosis factor α (TNFα) gene expression in the mouse macrophage cell line, RAW264.7. TNFα has been proven to be one of the main culprits o...

Trehalose is a natural disaccharide that is found in a diverse range of organisms but not in mammals. Autophagy is a process which mediates the sequestration, lysosomal delivery and degradation of proteins and organelles. Studies have shown that trehalose exerts beneficial effects through inducing autophagy in mammalian cells. However, whether trehalose or other saccharides can activate autopha...

Receptor-mediated apoptosis is proposed as an important regulator of keratinocyte homeostasis in human epidermis. We have previously reported that Fas/FasL interactions in epidermis are altered during cutaneous leishmaniasis (CL) and that keratinocyte death through apoptosis may play a pathogenic role for skin ulceration. To further investigate the alterations of apoptosis during CL, a keratino...

In vitro approaches to address key steps of chemical-induced skin sensitization have been developed, but there is uncertainty how keratinocytes, which play a crucial role not only regarding xenobiotic metabolism but also skin inflammation, impact on a chemical's potential and potency to activate dendritic cells. We investigated these aspects by coculturing THP-1 cells, as surrogate dendritic ce...