Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P42574 (caspase-3)
 45,978 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Sulfur mustard (SM) induces vesication via poorly understood pathways. The blisters that are formed result primarily from the detachment of the epidermis from the dermis at the level of the basement membrane. In addition, there is toxicity to the basal cells, although no careful study has been performed to determine the precise mode of cell death biochemically. We describe here two potential mechanisms by which SM causes basal cell death and detachment: namely, induction of terminal differentiation and apoptosis. In the presence of 100 microM SM, terminal differentiation was rapidly induced in primary human keratinocytes that included the expression of the differentiation-specific markers K1 and K10 and the cross-linking of the cornified envelope precursor protein involucrin. The expression of the attachment protein, fibronectin, was also reduced in a time- and dose-dependent fashion. Features common to both differentiation and apoptosis were also induced in 100 microM SM, including the rapid induction of p53 and the reduction of Bcl-2. At higher concentrations of SM (i.e., 300 microM), formation of the characteristic nucleosome-sized DNA ladders, TUNEL-positive staining of cells, activation of the cysteine protease caspase-3/apopain, and cleavage of the death substrate poly(ADP-ribose) polymerase, were observed both in vivo and in vitro. Both the differentiation and the apoptotic processes appeared to be calmodulin dependent, because the calmodulin inhibitor W-7 blocked the expression of the differentiation-specific markers, as well as the apoptotic response, in a concentration-dependent fashion. In addition, the intracellular Ca2+ chelator, BAPTA-AM, blocked the differentiation response and attenuated the apoptotic response. These results suggest a strategy for designing inhibitors of SM vesication via the Ca2+-calmodulin or caspase-3/PARP pathway.
J Invest Dermatol 1998 Jul
PMID:Sulfur mustard induces markers of terminal differentiation and apoptosis in keratinocytes via a Ca2+-calmodulin and caspase-dependent pathway. 966 88

Recent observations demonstrated that interleukin-1beta converting enzyme family proteases, now referred to as caspase family, play central roles in apoptosis, or programmed cell death. In this study, we tried to isolate and characterize epidermal caspases. By DEAE-Sephacel anion-exchange chromatography, human cornified cell extract showed two caspase-like fractions (F-I and F-II) with different substrate specificities. These were further purified by Sephacryl S-200, Mono Q ion exchange and Superose 6 gel chromatography. F-I showed a molecular weight of 30 kDa and specifically hydrolyzed acetyl-Asp-Glu-Val-Asp-methylcoumarinamide, a fluorogenic substrate for caspase-3 (CPP32) with a Km value of 13.8 microM. F-I generated a characteristic 85 kDa fragment from poly(ADP-ribose) polymerase. Inhibitor susceptibility of F-I was very similar to that of caspase-3, further confirming the caspase-3-like properties of F-I. In contrast, the molecular weight of F-II was estimated to be 110 kDa, which was much higher than the other caspases. F-II equally hydrolyzed acetyl-Asp-Glu-Val-Asp-methylcoumarinamide, and acetyl-Tyr-Val-Ala-Asp-methylcoumarinamide, caspase-1 (interleukin-1beta converting enzyme)-specific substrate, and was inhibited by acetyl-Tyr-Val-Ala-Asp-aldehyde and acetyl-Tyr-Val-Ala-Asp-aldehyde. Affinity labeling using biotinylated YVAD-cmk demonstrated several positive bands ranging from 25 to 35 kDa, supporting the hypothesis that F-II is a complex of multiple caspases. Reverse transcriptase-polymerase chain reaction analysis demonstrated that among known caspases tested, caspase-1, -2, -3, -4, and -7 were expressed in cultured human keratinocytes. These results suggest that multiple caspases are synthesized in human keratinocytes and are involved in terminal differentiation.
J Invest Dermatol 1998 Sep
PMID:Partial purification and characterization of two distinct types of caspases from human epidermis. 974 Feb 25

We analyzed changes of growth and apoptotic cell death in human hair follicles. In anagen hair follicles, terminal deoxynucleotidyltransferase-mediated deoxyuridine triphosphate-biotin nick labeling-positive cells were observed in the keratogenous zone of the upper bulb matrix, the inner root sheath, and the companion layer of the outer root sheath. DNA ladder formation was also detected in anagen hair follicles. In catagen hair follicles, the lower bulb matrix cells around the dermal papilla and the outer layer cells of the outer root sheath became strongly positive, showing that apoptosis in catagen hair is distinct from that in anagen hair. We also confirmed the mRNA expression of four caspases (caspase-1, caspase-3, caspase-4, and caspase-7) in anagen hair follicles by reverse transcriptase-polymerase chain reaction and in situ hybridization. When human anagen hair follicles were cultured in the presence of transforming growth factor-beta or tumor necrosis factor-alpha in the serum-free medium, transforming growth factor-beta but not tumor necrosis factor-alpha induced catagen-like morphologic changes, which were indistinguishable from normal catagen hair follicles. Tumor necrosis factor-alpha, however, strongly inhibited the elongation of the hair shaft in a dose-dependent manner, accompanied by abnormal morphology and increased cell death in the bulb matrix cells. Our results suggest that apoptosis in hair follicles involves two different types. One is related to the terminal differentiation of follicular epithelial cells in anagen hair. The other occurs as a major driving force to eliminate the distinct portion of epithelial components in catagen hair. Furthermore, this study strongly indicates that the transforming growth factor-beta pathway is involved in the induction of catagen phase in human hair cycle.
J Invest Dermatol 1998 Dec
PMID:Analysis of apoptotic cell death in human hair follicles in vivo and in vitro. 985 1

Exposure of human keratinocyte HaCaT cells to ultraviolet B-irradiation induced apoptotic morphologic changes. In this study, we found that the ultraviolet B irradiation (0.25 J per cm2) induced phosphorylation of p38 mitogen-activated protein kinase and c-jun N-terminal protein kinase, and also significant activation of caspase-3 (CPP32-like protease) and a small increase of caspase-1 (ICE-like protease) activity in the early stages of ultraviolet B-induced apoptosis. Pretreatments of the cells with a p38 mitogen-activated protein kinase inhibitor, SB203580, and a caspase-3 inhibitor, Ac-Asp-Met-Gln-Asp-1-aldehyde, suppressed the ultraviolet B irradiation-induced apoptosis by approximately 60% as estimated by nuclear staining and DNA laddering. Pretreatment with caspase-1 inhibitor, Ac-Tyr-Val-Lys-Asp-aldehyde was without effect. Ultraviolet B-induced caspase-3 activation resulted in cleavage of poly(ADP) ribose polymerase, which was abolished by the caspase-3 inhibitor. SB203580 pretreatment prevented activation of caspase-3 and caspase-1, and also suppressed the cleavage of poly(ADP) ribose polymerase. Neither ceramide generation nor sphingomyelinase activation (neutral and acid) was observed in the ultraviolet B-irradiated HaCaT cells. Also various antioxidants did not affect the caspase activation induced by ultraviolet B irradiation. These results indicated that activation of p38 mitogen-activated protein kinase upstream of caspases may play an important part in the apoptotic process of keratinocytes exposed to ultraviolet B irradiation.
J Invest Dermatol 1999 May
PMID:Activation of p38 mitogen-activated protein kinase and caspases in UVB-induced apoptosis of human keratinocyte HaCaT cells. 1023 70

UVB-irradiation induces apoptosis in primary keratinocytes (KC) and KC-derived cell-lines A431 and HaCaT. Here we report on the inhibition of UV induced KC-apoptosis by hepatocyte growth factor/scatter factor (HGF/SF). The protective effect of HGF/SF for UVB-irradiated primary KC was observed at concentrations as low as 1 ng/ml HGF and was confirmed by demonstration of the inhibition of nucleosome-release and the activation of caspase-3. In contrast to the observation with primary KC HGF/SF had no effect on the survival of A431 and HaCaT cells after UVB-irradiation, despite the fact that we could demonstrate that these cells functionally express the HGF/SF receptor c-met. When blocking signalling pathways initiated by c-met, we found that the inhibition of the phosphatidylinositol-3-OH (PI-3) kinase by wortmannin or LY294002 led to a total inhibition of the anti-apoptotic effect of HGF/SF, whereas the blockade of the MAP-kinase pathway by PD90859 had no effect. This represents the first demonstration of an involvement of the PI-3 kinase pathway in the anti-apoptotic effect of HGF/SF. In conclusion, our data demonstrate that HGF/SF is able to rescue KC but not autonomously growing KC cell lines from apoptosis induced by UVB. Since in vivo HGF/SF is produced by mesenchymal cells, this mechanism may represent an important paracrine loop in the skin supporting the survival of KC after UV-injury.
J Invest Dermatol 1999 Dec
PMID:001: hepatocyte growth factor/scatter factor inhibits UVB induced apoptosis of human keratinocytes via the PI-3-kinase pathway 1059 64

The human disease xeroderma pigmentosum (XP) involves DNA repair and replication deficiencies that predispose homozygous individuals to a 1000-fold increase in nonmelanoma and melanoma skin cancers. Two major forms of XP are known with different biochemical defects: one form lacks nucleotide excision repair (NER); the other lacks the capacity to replicate damaged DNA. Since the clinical symptoms of both kinds of patients are almost the same, the different cellular defects must be reconciled with common clinical outcomes. An additional question among the NER defective patients is how to reconcile widely different skin and central nervous system symptoms with mutations in the same biochemical pathway. XP involves seven genes of the NER system (XPA through G). The XPA gene codes for a protein that is central to NER and binds to a variety of UV light and chemical damage to DNA. It also acts as a nucleation center for other repair proteins to attach and carry out excision and replacement synthesis. Mutations in XPA that are within the DNA binding site produce more severe CNS disorders, than mutations in the C-terminal region of the protein that interacts with the TFIIH complex. In contrast, mutations in two members of the TFIIH complex, the XPB and XPD genes are generally very severe with both skin and CNS disorders. Missense mutations within the helicase regions of these genes are associated with DNA repair deficiencies and XPD; mutations elsewhere in these genes are correlated with symptoms of XP and Cockayne syndrome and trichothiodystrophy. This raises the question whether the CNS disorders of XPA, XPB, and XPD patients are similar, or whether a careful clinical evaluation might reveal different mechanisms of development. The XP variant lacks the capacity to replicate damaged DNA due to mutations in hRad30, a damage-specific polymerase eta. The phenotype of XP variant cells becomes unstable and the cells become much more UV-sensitive when they are transformed by methods that inactivate p53. On a p53 negative background, the induction of recombination between sister chromatids occurs much more extensively than in normal cells, and we have evidence that DNA double strand breaks which trigger an apoptotic pathway involving caspase-3 are involved. The pathway for UV carcinogenesis may be the same for all XP patients if the ultimate cause of genomic instability is an increase in replication of damaged DNA by the error-prone polymerase zeta. The presence of unrepaired damage in the NER defective groups of XP would present more substrate for the error-prone system leading to increased mutation rates. The absence of pol eta would require cells to use the error-prone pol zeta pathway, also increasing mutation rates from UV damage. A common pathway for increased mutagenesis therefore underlies both forms of XP.
J Dermatol Sci 2000 May
PMID:Common pathways for ultraviolet skin carcinogenesis in the repair and replication defective groups of xeroderma pigmentosum. 1069 59

The quantitative measurement of the induction of apoptosis in cells grown in vitro can be accomplished using a variety of proven methods. However, the quantitative assay of apoptosis within an intact tissue is very laborious and the results can be misleading. We have established a method to quantitatively analyze the induction of apoptosis in human epidermis following UVB irradiation. The assay is based on the activation of the apoptotically induced enzyme caspase 3, using a synthetic caspase 3 substrate. The activation of caspase 3 was shown to correlate with the induction of apoptosis in human keratinocytes cultures as a monolayer. We then demonstrated that the activation of caspase 3 could be measured from UVB-irradiated whole skin. The induction of apoptosis was confirmed by cellular morphology and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labeling. Therefore, we concluded that the measurement of caspase 3 specific activity in UVB-irradiated human epidermis was an efficient, inexpensive, and accurate method to quantitate UVB-induced apoptosis in vivo.
Exp Dermatol 2000 Jun
PMID:Quantitative analysis of UVB-induced apoptosis in human epidermis. 1083 16

In order to maintain epidermal structural homeostasis, keratinocytes need to modulate their proliferation, differentiation, and cell death. Although terminal differentiation of keratinocytes is characterized by cornified cell envelope (CE) formation and one major mechanism of cell death is apoptosis, the precise relationship between these processes remains obscure. Using normal human cultured keratinocytes (NHK), we compared A23187-induced CE formation and ultraviolet B irradiation (UVB)-induced apoptosis. A23187 stimulated CE formation in 1 mM Ca(2+)-pretreated NHK cells. CE formation was detected by 1 h and the maximal induction was observed at 6 h. Morphological analysis using acridine orange staining revealed that UVB-irradiated NHK cells show distinctive round, homogeneous fragmented nuclear beads, a characteristic feature of apoptotic cells, while A23187-treated cells showed enlarged nuclei with weak chromatin staining, which is not typical of apoptosis. The UVB-irradiated NHK cells did not show CE formation. Caspase activation is a characteristic event during apoptosis. Although UVB irradiation increased caspase 3 activity, no increase in caspase 3 activity was detected during A23187-induced CE formation. Multiple nucleosome-sized fragments of DNA were observed in UVB-treated NHK cells, but not in A23187-treated NHK cells. FACS analyses using anti-annexin V antibody and propidium iodide (PI) showed that UVB irradiation induced both annexin V-positive and PI-negative early apoptotic cells and annexin V-positive and PI-positive late apoptotic cells. On the other hand, A23187-treated NHK cells showed only annexin V-negative and PI-positive non-apoptotic dying cells. Cell death assay revealed a significantly increased apoptotic cells in UVB-irradiated NHK cells, but not in A23187-treated NHK cells. UVB irradiated NHK cells showed increased cytosolic transglutaminase activity, while A23187-treated NHK cells showed increased membrane-associated transglutaminase activity. These results indicate that CE formation is distinct from apoptosis in epidermal keratinocytes.
J Dermatol Sci 2000 Aug
PMID:Cornified cell envelope formation is distinct from apoptosis in epidermal keratinocytes. 1095 41

The purpose of this study was to ascertain whether the antiproliferative effect of 15-hydroxyeicosatrienoic acid (15-HETrE), a monohydroxy fatty acid generated from dihomo-gamma-linolenic acid, in an experimentally induced guinea pig hyperproliferative model involves alterations in nuclear transcription factor (AP-1) and apoptosis. The topical application of docosahexaenoic acid (DHA) to normal guinea pig skin elicited a severe hyperplasia which was accompanied by the suppression of AP-1 expression in a time-dependent manner. Since apoptosis is pivotal in tissue turnover, the expression of two apoptotic proteins (Bcl-2 and caspase-3) after DHA and 15-HETrE treatment was explored. DHA-induced hyperproliferation enhanced the expression of Bcl-2 (an antiapoptotic protein) but inhibited the expression of caspase-3 (an apoptotic protein). 15-HETrE, on the other hand, reversed the DHA-induced epidermal hyperplasia, and upregulated epidermal AP-1 expression. These events paralleled the suppression of Bcl-2 and the elevation of caspase-3. Taken together, these results suggest that the antiproliferative effect of 15-HETrE may, at least in part, be via the modulation of AP-1 and apoptosis.
Arch Dermatol Res 2000 Aug
PMID:15-hydroxyeicosatrienoic acid (15-HETrE) suppresses epidermal hyperproliferation via the modulation of nuclear transcription factor (AP-1) and apoptosis. 1099 74

The heat shock response is a highly conserved reaction common to all cells and organisms. It has been reported that hyperthermic treatment can induce the expression of the heat shock protein (HSP) and can protect cells from ultraviolet (UV) B radiation. In this study, we evaluated the effects of induced HSP70 on resistance to UV radiation. G361 amelanotic human melanoma cells were irradiated with increasing doses of UVB. UVB irradiation caused apoptotic cell death in these cells. Following transfection with MFG.hsp70.puro plasmid, the expression of HSP70 was determined. Compared to control vector-transfected cells, hsp70-transfected cells showed significantly elevated levels of HSP70 and were highly resistant to UVB irradiation. In order to investigate the effects of HSP70 on the apoptotic pathway, the changes in caspase-3 and PARP were analyzed. Following UVB irradiation, activation of caspase-3 and cleavage of PARP were observed in control vector-transfected cells, and the changes in these molecules were inhibited in the hsp70-transfected cells. These results suggest that UVB-induced apoptosis of melanoma cells is accompanied by caspase-3 activation and PARP cleavage, which can be prevented by an overexpression of HSP70.
Arch Dermatol Res 2000 Oct
PMID:Overexpression of HSP70 prevents ultraviolet B-induced apoptosis of a human melanoma cell line. 1114 69


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