3-Aminobenzamide protects primary human keratinocytes from UV-induced cell death by a poly(ADP-ribosyl)ation independent mechanism

Chronic UV irradiation results in many changes in the skin, including hyperplasia, changes in dermal structures, and alteration of pigmentation. Exposure to UVB leads to cutaneous damage, which results in inflammation characterized by increased NF-κB activation and the induction of inflammatory cytokines, such as tumor necrosis factor (TNF), interleukin- (IL-) 1, or IL-8. IL-1 secretion is the result of inflammasome activation which is besides apoptosis, a result of acute UVB treatment. Inflammasomes are cytosolic protein complexes whose formation results in the activation of proinflammatory caspase-1. Key substrates of caspase-1 are IL-1β and IL-18, and the cytosolic protein gasdermin D (GSDMD), which is involved in inflammatory cell death. Here, we demonstrate that UVB-induced inflammasome activation leads to the formation of ASC specks. Our findings show that UVB provokes ASC speck formation in human primary keratinocytes prior to cell death, and that specks are, opposed to the perinuclear cytosolic localization in myeloid cells, formed in the nucleus. Additionally, we showed by RNAi that NLRP1 and not NLRP3 is the major inflammasome responsible for UVB sensing in primary human keratinocytes. Formation of ASC specks indicates inflammasome assembly and activation as their formation in hPKs depends on the presence of NLRP1 and partially on NLRP3. Nuclear ASC specks are not specific for NLRP1/NLRP3 inflammasome activation, as the activation of the AIM2 inflammasome by cytosolic DNA results in ASC specks too. These nuclear ASC specks putatively link cell death to inflammasome activation, possibly by binding of IFI16 (gamma-interferon-inducible protein) to ASC. ASC can interact upon UVB sensing via IFI16 with p53, linking cell death to ASC speck formation.

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Apoptosis Inhibition by the Human DEK Oncoprotein Involves Interference with p53 Functions

Molecular and Cellular Biology ◽

10.1128/mcb.00430-06 ◽

2006 ◽

Vol 26 (20) ◽

pp. 7506-7519 ◽

Cited By ~ 78

Author(s):

Trisha M. Wise-Draper ◽

Hillary V. Allen ◽

Elizabeth E. Jones ◽

Kristen B. Habash ◽

Hiroshi Matsuo ◽

...

Keyword(s):

Cell Death ◽

Protein Function ◽

Target Genes ◽

Cellular Proliferation ◽

Apoptotic Cell ◽

Human Keratinocytes ◽

Dominant Negative ◽

Osteosarcoma Cell ◽

Primary Human Keratinocytes ◽

Human Carcinogenesis

ABSTRACT The DEK proto-oncogene has been associated with human carcinogenesis—either as a fusion with the CAN nucleoporin protein or when transcriptionally upregulated. Mechanisms of intracellular DEK functions, however, have remained relatively unexplored. We have recently demonstrated that DEK expression is induced by the high-risk human papillomavirus (HPV) E7 protein in a manner which is dependent upon retinoblastoma protein function and have implicated DEK in the inhibition of cellular senescence. Additionally, overexpression of DEK resulted in significant life span extension of primary human keratinocytes. In order to determine whether DEK expression is required for cellular proliferation and/or survival, we monitored cellular responses to the knockdown of DEK in cancer and primary cells. The results indicate that DEK expression protects both HPV-positive cancer and primary human cells from apoptotic cell death. Cell death in response to DEK depletion was accompanied by increased protein stability and transcriptional activity of the p53 tumor suppressor and consequent upregulation of known p53 target genes such as p21CIP and Bax. Consistent with a possible role for p53 in DEK-mediated cell death inhibition, the p53-negative human osteosarcoma cell line SAOS-2 was resistant to the knockdown of DEK. Finally, expression of a dominant negative p53 miniprotein inhibited DEK RNA interference-induced p53 transcriptional induction, as well as cell death, thus directly implicating p53 activation in the observed apoptotic phenotype. These findings suggest a novel role for DEK in cellular survival, involving the destabilization of p53 in a manner which is likely to contribute to human carcinogenesis.

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Cryptotanshinone from Salvia miltiorrhiza Bunge lowers the Cytokeratin 1/10 expression in primary human Keratinocytes in vitro

10.1055/s-0037-1608052 ◽

2017 ◽

Author(s):

S Esch ◽

A Hensel ◽

S Brandt ◽

S König

Keyword(s):

Salvia Miltiorrhiza ◽

Human Keratinocytes ◽

Salvia Miltiorrhiza Bunge ◽

Primary Human Keratinocytes

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Faculty Opinions recommendation of Robust production and passaging of infectious HPV in squamous epithelium of primary human keratinocytes.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1144927.602030 ◽

2009 ◽

Author(s):

Cheng-Ming Chiang

Keyword(s):

Squamous Epithelium ◽

Human Keratinocytes ◽

Primary Human Keratinocytes

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Hydrogen-Generating Silica Material Prevents UVA-Ray-Induced Cellular Oxidative Stress, Cell Death, Collagen Loss and Melanogenesis in Human Cells and 3D Skin Equivalents

Antioxidants ◽

10.3390/antiox10010076 ◽

2021 ◽

Vol 10 (1) ◽

pp. 76

Author(s):

Li Xiao ◽

Mai Mochizuki ◽

Taka Nakahara ◽

Nobuhiko Miwa

Keyword(s):

Oxidative Stress ◽

Cell Death ◽

Annexin V ◽

Human Keratinocytes ◽

Absorption Capacity ◽

Human Cells ◽

Skin Equivalents ◽

Type Iv ◽

Silica Material ◽

3D Skin

Ultraviolet-A (UVA) irradiation induces harmful effects on skin cells and accelerates skin aging through oxidative stress. In this study, the effects of a hydrogen-generating silica material named ULH-002 against UVA injuries in human cells and 3D skin equivalents were investigated. The oxygen radical absorption capacity (ORAC) assay showed that both freshly prepared ULH-002 solutions and 7-day-old solutions exhibited equal peroxyl radical (ROO·) scavenging activities concentration-dependently. CellROX® green/orange staining showed that ULH-002 could reduce UVA-induced oxidative stress in human keratinocytes HaCaT and human gingival fibroblasts (HGFs). ULH-002 significantly prevented UVA-induced apoptotic/necrotic cell death and cell-viability decline in HGFs and keratinocytes, as shown by Annexin V/PI apoptosis assay and PrestoBlue assay, respectively. Immunostaining showed that ULH-002 prevented the UVA-induced deterioration of expression of both type IV and I collagens in the 3D skin equivalents, and similarly in monolayer HGFs. UVA-enhanced melanogenesis was observed in human melanocytes HMV-II and HMV-II cell-containing 3D skin equivalents, but markedly prevented by ULH-002 as demonstrated by Fontana–Masson’s staining. In conclusion, our data suggested that ULH-002 could protect human keratinocytes and fibroblasts from UVA-induced injuries, prevent the loss of type IV and I collagens, as well as reduce melanogenesis. ULH-002 might be developed as a skin care reagent in the cosmetic industry.

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