The present study was designed to investigate the protective effect of ethanol extracts from Lindera coreana leaves (LCE) on UVB-induced oxidative stress in HaCaT keratinocytes. The HaCaT cells were pretreated with LCE for 24 h and then exposed to UVB (20 mJ/cm2) for 2 h. UVB significantly decreased the cell viability (p

The present study was designed to investigate the protective effect of ethanol extracts from Lindera coreana leaves (LCE) on UVB-induced oxidative stress in HaCaT keratinocytes. The HaCaT cells were pretreated with LCE for 24 h and then exposed to UVB (20 mJ/cm2) for 2 h. UVB significantly decreased the cell viability (p

OBJECTIVES Experimental models are of importance to study the pathogenesis of middle ear cholesteatoma, however, they were not established until now. We aimed to develop in vitro model of middle ear cholesteatoma using primary keratinocytes and fibroblasts isolated from cholesteatoma tissue. HaCaT cell line was used as a "skin equivalent" and to compare the grade of homogeneity between choleste...

Exposure of epidermal keratinocytes to UVB radiation leads the intracellular formation tryptophan photoproducts which subsequently activate aryl hydrocarbon receptor (AHR) induce mal-/adaptive stress responses. Previously, we have found that AHR represses nucleotide excision repair and apoptosis in UVB-irradiated thereby contributes skin photocarcinogenesis mice. The mechanisms by interferes wi...

Arsenic is a carcinogen that poses a significant health risk in humans. Based on evidence that arsenic has differential effects on human, rodent, normal, and transformed cells, these studies addressed the relative merits of using normal human epidermal keratinocytes (NHEK) and immortalized human (HaCaT) and mouse (HEL30) keratinocytes when examining stress-induced gene expression that may contr...

Previous studies addressing functional aspects of nuclear factor KB (NF-KB) activation in normal and transformed keratinocytes revealed complex and seemingly contradictory roles of this transcription factor in this cell type. In normal skin, NF-KB signaling seems to inhibit squamous cell carcinoma development whereas, in squamous cell carcinoma themselves, deregulated NF-KB expression and/or si...

We studied the expression of arachidonate 5-lipoxygenase (5-LO) in a cell line of human keratinocytes (HaCaT) and in normal human skin keratinocytes in tissue culture. In undifferentiated keratinocytes 5-LO gene expression was low or undetectable as determined by 5-LO mRNA, protein, cell-free enzyme activity, and leukotriene production in intact cells. However, after shift to culture conditions...

Peroxisome proliferator-activated receptor-β/δ (PPARβ/δ) function and receptor cross-talk with other nuclear receptors, including PPARγ and retinoic acid receptors (RARs), was examined using stable human HaCaT keratinocyte cell lines over-expressing PPARβ/δ or PPARγ. Enhanced ligand-induced expression of two known PPAR target genes, adipocyte differentiation-related protein (ADRP) and angiopoie...

The epidermal growth factor (EGF) receptor plays an important role in epithelial cells by controlling cell proliferation and survival. Keratinocytes also express another class of receptor tyrosine kinases, the neurotrophin receptors. To analyze the biological role of the neurotrophin brain-derived neurotrophic factor (BDNF) in keratinocytes, we expressed the BDNF receptor TrkB in immortalized h...

This study focused on the protective actions of Empetrum nigrum against ultraviolet B (UVB) radiation in human HaCaT keratinocytes. An ethyl acetate extract of E. nigrum (ENE) increased cell viability decreased by exposure to UVB rays. ENE also absorbed UVB radiation and scavenged UVB-induced intracellular reactive oxygen species (ROS) in HaCaT keratinocytes. In addition, ENE shielded HaCaT ker...