• Biomolecules & Therapeutics
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• v.12 no.1
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• pp.1-8
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• 2004

In chronic airway inflammatory diseases such as asthma and chronic bronchitis, it has been suggested that matrix metalloproteinases secreted from infiltrating neutrophil contribute the pathogenesis of the disease and have been a focus of intense investigation. We report here that hamster tracheal surface epithelial goblet cells (HTSE cells) produce matrix metalloproteinase-2 (MMP-2) and tissue inhibitor of metalloproteinase-2 (TIMP-2). Matrix metalloproteinase activities were investigated using [$^3H$]collagen-digestion assay and gelatin zymography. The subtype of matrix metalloproteinases expressed from HTSE cells was MMP-2 (gelatinase A), which was determined by Western blot with various subtype selective anti-matrix metalloproteinase antibodies. The MMP-2 and TIMP-2 cDNAs from HTSE cells were partially cloned by RT-PCR and they reveal more than 90% of sequence homology with those from human, rat and mouse. The collagenolytic activity was increased with the secretory differentiation of the HTSE cell and it was found that zymogen activation was responsible for the increased MMP-2 activity in HTSE cells. The results from the present study suggest that the metaplastic secretory differentiation of airway goblet cells may affect chronic airway inflammatory process by augmenting the zymogen activation of MMP-2.

• Molecules and Cells
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• v.26 no.6
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• pp.606-610
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• 2008

Phenoloxidase (PO), a melanin-forming enzyme around the foreign bodies, is an important component of the host defense system in invertebrates. Pro-PO is the enzymatically inactive zymogen form of PO. In the Drosophila genome, three Pro-PO isoforms have been identified to date. These include Pro-PO1 and 2, which are primarily expressed in crystal cells, and Pro-PO3, which is predominantly found in the lamellocytes. In this study, we demonstrated that Drosophila Pro-PO3, but not Pro-PO1 or 2, is enzymatically active in its zymogen form. These findings were evidenced by spectacular melanin forming capacities of various cells and tissues that overexpressed these pro-enzymes. Furthermore, the melanization phenotype observed in the lamellocyte-enriched $hop^{Tum-l}$ mutant was drastically reduced in the absence of PPO3, indicating that PPO3 plays a major role in the lamellocyte-mediated spontaneous melanization process. Taken together, these findings indicate that the biochemical properties, activation mode and in vivo role of Pro-PO3 are likely distinct from those of the other two Pro-PO enzymes involved in Drosophila physiology.

• The Korean Journal of Zoology
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• v.30 no.2
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• pp.193-209
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• 1987

Patterns of amylase secretion in mouse pancreatic fragments were studied over a period of time after the tissue was stimulated by acetyicholine and MNNG. MNNG is known to activate guanylate cyclase and thus increase the cGMP concentration in the pancreatic acinar cell. These amylase secretion patterns were studied to investigate the role of cGMP in reaction cascade during secretion response of the tissues stimulated by acetyicholine. Cellular response of amylase secretion in the pancreas by acetyicholine was divided into two phases. During the first phase, zymogen granules which had existed in the cells were secreted by the action of $Ca^2$+ and calmodulin immediately after secretagogue administration, this being known as the initial response. When the tissue was stimulated by acetylcholine in a $Ca^2$+-deficient medium or one containing trifluoperazine as a calmodulin antagonist, this initial response was reduced. In the second phase, newly formed zymogen granules were secreted as sustained response after protein synthesis was triggered by secretagogue. This response was provoked by an activation of protein kinase C. When either cycloheximide as a protein synthesis inhibitor or dibucaine as a protein kinase C inhibitor were added to the incubation medium, this sustained response was remarkablely depressed in the pancreatic fragments stimulated with acetylcholine. In the pancreatic acinar cell, phosphatidylinositol turnover plays an important role in the secretion response and hexachlorocyclohexane inhibits this phosphatidylinositol turnover. The pancreatic tissue treated with the hexachlorocyclohexane exhibited inhibition on both initial and sustained responses of amylase secretion by acetylcholine. MNNG also accelerated amylase secretion from the tissue gradually along incubation time. The 22 minutes fraction of the pancratic secretion after administration of both acetylcholine and MNNG showed higher amylase activity than the neighboring fractions. Guanylate cyclase potentiated the sustained response. Even if it is experimented with an indirect method, guanylate cyclase was found responsible for activation of the sustained response of a step prior to the action of protein kinase C. As conclusion, it was considered that amylase secretion in mouse pancreatic fragments stimulated by acetylcholine is a three phasic response.

• BMB Reports
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• v.46 no.11
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• pp.544-549
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• 2013

High mobility group box 1 (HMGB1) is involved in the pathogenesis of vascular diseases. Unlike activated protein C (APC), the activation of PAR-1 by thrombin is known to elicit proinflammatory responses. To determine whether the occupancy of EPCR by the Gla-domain of APC is responsible for the PAR-1-dependent antiinflammatory activity of the protease, we pretreated HUVECs with the PC zymogen and then activated PAR-1 with thrombin. It was found that thrombin downregulates the HMGB1-mediated induction of both TNF-${\alpha}$ and IL-6 and inhibits the activation of both p38 MAPK and NF-${\kappa}B$ in HUVECs pretreated with PC. Furthermore, thrombin inhibited HMGB1-mediated hyperpermeability and leukocyte adhesion/migration by inhibiting the expression of cell adhesion molecules in HUVECs if EPCR was occupied. Collectively, these results suggest the concept that thrombin can initiate proinflammatory responses in vascular endothelial cells through the activation of PAR-1 may not hold true for normal vessels expressing EPCR under in vivo conditions.

• BMB Reports
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• v.42 no.8
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• pp.506-510
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• 2009

The Toll signalling pathway in invertebrates is responsible for defense against Gram-positive bacteria and fungi, leading to the expression of antimicrobial peptides via NF-$\kappa$B-like transcription factors. Gram-negative binding protein 3 (GNBP3) detects beta-1,3-glucan, a fungal cell wall component, and activates a three step serine protease cascade for activation of the Toll signalling pathway. Here, we showed that the recombinant N-terminal domain of Tenebrio molitor GNBP3 bound to beta-1,3-glucan, but did not activate down-stream serine protease cascade in vitro. Reversely, the N-terminal domain blocked GNBP3-mediated serine protease cascade activation in vitro and also inhibited beta-1,3-glucan-mediated antimicrobial peptide induction in Tenebrio molitor larvae. These results suggest that the N-terminal GNBP homology domain of GNBP3 functions as a beta-1,3-glucan binding domain and the C-terminal domain of GNBP3 may be required for the recruitment of immediate down-stream serine protease zymogen during Toll signalling pathway activation.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.10
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• pp.5027-5031
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• 2012

This study was conducted to investigate the expression of survivin and caspase 3 in oral squamous cell carcinoma and peritumoral tissue, and possible pathogenesis mechanisms. We used ELISA and western blotting to detect the protein expression levels of survivin and caspase 3 in tissue. In situ hybridization and real-time PCR were applied to assess mRNA expression levels. In this study, 13 tumor samples and 13 peritumoral tissue samples were collected from oral squamous cell carcinoma patients and 10 normal tissue samples obtained from patients without tumor. The result showed that the protein and mRNA expression of survivin in carcinoma was the highest among three types of tissue; following was that in peritumoral tissue. No difference in caspase 3 zymogen between peritumoral tissue and normal tissue could be found, while it was evidently decreased in carcinoma tissue. Activated caspase 3 was detected in normal tissue but could not be identified in peritumoral or carcinoma tissue. Our results indicate that the expression of survivin is apparently elevated in tumoral and peritumoral tissue. Expression of activated caspase 3 was not detected in tumoral tissue and the expression of caspase 3 zymogen was decreased in tumoral tissue. Our findings suggest that survivin may inhibit both synthesis and activation of caspase 3, hence inhibiting cell apoptosis and facililitating eventual development of oral squamous cell carcinoma.

• International Journal of Oral Biology
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• v.30 no.4
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• pp.111-116
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• 2005

Resveratrol (3,4',5-trihydroxy-trans-stilbene), a naturally occuring polyphenol compound which present in the skin of grapes and red wine has been considered to posses chemopreventive and antioxidant properties. However, little is known about the cellular actions by which resveratrol mediates its therapeutic effects. In this study, the effect of resveratrol on cell proliferation and induction of apoptosis in human osteogenic sarcoma (HOS) cells was investigated. $IC_{50}$ value was determined to be approximately $6.0{\mu}g/ml$. Chromosomal DNA framgmentation analysis showed the appearance degraded DNA in time-and dose-dependent manner upon treatment of resveratrol. In order to observe the molecular mechanism involved in resveratrol-induced apoptosis, Western blot analysis was performed. We observed the decrease in the level of procaspase-3, the zymogen form of active caspase-3 in resveratrol-treated cells. This result implies that caspase-3 is activated upon treatment of resveratrol. The activation of caspase-3 was confirmed by the cleavage of poly(ADP-ribose) polymerase. Taken together, our data demonstrate that resveratrol has anti-proliferative effect on HOS cells and induced apoptosis through activation of caspase-3 and PARP cleavage.

• Proceedings of the Zoological Society Korea Conference
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• 1995.10b
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• pp.83-83
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• 1995

The three chitin synthetases of Saccharomyces cerevisiae, Chs1, Chs2, and Chs3, participate in septum and cell wall formation of vegetative cells and in wall morphogenesis of conjugating cells and spores. Because of the differences in the nature and in the time of execution of their functions, the synthetases must be specifically and individually regulated. The nature of that regulation has been investigated by measuring changes in the levels of the three synthetases and of the messages of the three corresponding gnes, CDSI, CHS2, and CAL1/CSD2/DITl0l(referred to below as CAL1), during the budding cycles. For Chs1 and Chs3, posttranslational regulation, probably by activation of latent forms, appears to be predominant. Since Chs2, like Chs1, is found in the cell in the zymogenic form, a posttranslational activation step appears to be necessary for this synthetase also. The regulation mechanism was investigated to search the relationship of CAL1, CAL2 and CALJ which is involved in Chs3 activity us ing different assay methods other than previous one. Treatment of Chs3-containing membranes with detergents drastically reduced the enzymatic activity. Activity could, however, be restored by subsequent incubation with trypsin or other pro teases in the presence of UDPGlcNAc. Experiments wi th mutants in the three genes invoIved in Chs3 activity-CAL1, CAL2, and CALJ-showed that only CAL1 and CALJ are required for the proteaseelicited (zymogenic) activity. It is concluded that Chs3 IS a zymogen and that the CAL2 product funct ions as its activator.ivator.

• BMB Reports
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• v.36 no.1
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• pp.128-137
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• 2003

Matrix metalloproteinases (MMPs), zinc dependent proteolytic enzymes, cleave extracellular matrix (ECM: collagen, laminin, firbronectin, etc) as well as non-matrix substrates (growth factors, cell surface receptors, etc). The deregulation of MMPs is involved in many diseases, such as tumor metastasis, rheumatoid arthritis, and periodontal disease. Metastasis is the major cause of death among cancer patients. In this review, we will focus on the roles of MMPs in tumor metastasis. The process of metastasis involves a cascade of linked, sequential steps that involve multiple host-tumor interactions. Specifically, MMPs are involved in many steps of tumor metastasis. These include tumor invasion, migration, host immune escape, extravasation, angiogenesis, and tumor growth. Therefore, without MMPs, the tumor cell cannot perform successful metastasis. The activities of MMPs are tightly regulated at the gene transcription levels, zymogen activation by proteolysis, and inhibition of active forms by endogenous inhibitors, tissue inhibitor of metalloproteinase (TIMP), and RECK. The detailed regulations of MMPs are described in this review.

• Journal of fish pathology
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• v.14 no.2
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• pp.81-90
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• 2001

The histological responses of the flounder, Paralichthys olivaceus to copper were examined in the gill, hepatopancreas and kidney. In control group, from 5 weeks mucous cells and chloride cells were increased in the gill, and numerous hemocytes and some melano-macrophagocytes were observed in the hepatopancreas and kidney. The minimum concentration for histological responses was 0.05mg/$\ell$/7d. In this group gill and hepatopancreas showed chloride cell activation, hepatocyte activation, pancreatic zymogen reduction, and congestion, and melanomacrophagocytes were observed in the kidney. From the histological observations, the critical concentrations for dysfunctionality were 0.18mg/$\ell$/21d in the gill, 0.18mg/$\ell$/14d in the hepatopancreas and 0.08mg/$\ell$/14d in the kidney, respectively.