Soon- Jeong

Secretory leukocyte protease inhibitor is associated with MMP-2 and MMP-9 to promote migration and invasion in SNU638 gastric cancer cells.

Secretory leukocyte protease inhibitor (SLPI) protects tissue from proteases, and promotes cell proliferation and healing during inflammatory response. SLPI is also overexpressed in gastric, lung and ovarian cancers, which accelerates the metastasis of cancer cells. Matrix metalloproteinases-2, -9 (MMP-2 and MMP-9) are overexpressed in high metastatic cancers, and promote the migration of cancer cells through collagen degradation. SLPI and MMP-2, -9 are critical factors in stimulating the metastatic processes but there are no reports of a direct correlation between these molecules. Therefore, this study examined the role of SLPI related to MMP-2 and MMP-9 using two gastric cancer cell lines, such as characterized non-metastatic SNU484 and highly metastatic SNU638 cells. SLPI, MMP-2 and MMP-9 mRNA and protein expression were higher in SNU638 cells than in SNU484 cells. In addition, the rate of cell migration and invasion was higher in the SNU638 cells than in SNU484 cells. Interestingly, after treatment with SLPI, the rate of migration and invasion was higher in the SNU484 cells than in the positive control (PC) SNU484 cells. The rate of migration was also higher in the SNU638 cells after SLPI treatment than in the SNU638 cells (PC) but the invasion rate was not changed. The expression and secretion of MMP-2 and MMP-9 as well the rate of cell migration and invasion were significantly lower in SLPI-siRNA transfected SNU638 cells (si-SLPI/SNU638) but higher in SLPI-treated SNU484 cells (SNU484 + SLPI). Strong Elk-1 phosphorylation was detected in SNU484 + SLPI and SNU638 cells but was barely detectable in SNU484 and si-SLPI/SNU638 cells. These results show that SLPI promotes the metastasis of SNU638 gastric cancer cells by increasing MMP-2 and MMP-9 expression through Elk-1 signaling, indicating its role as a signaling molecule not a protease inhibitor.

Therapeutic Effect of Total Ginseng Saponin on Skin Wound Healing

In this study, we investigated the effects of total ginseng saponin (TGS) on the cutaneous wound healing process using histological analysis. A total of 24 ICR mice, 5-weeks-old, were used for all in vivo experiments. Mice were divided into control and TGS-treated groups and four equidistant 1-cm full-thickness dorsal incisional wounds were created. The wounds were extracted at days 1, 3, 5, and 7 post-injury for histomorphometrical analysis including wound area and contracture measurements, keratinocyte migration rate, and calculation of infiltrating inflammatory cells. The results showed that the wound area was smaller and keratinocyte migration rate was higher in the TGS-treated group than that of the control group from days 3 to 7. Inflammatory cells in the TGS-treated group at days 1 and 3 were reduced compared to the control group. Wound contraction in the TGS-treated group was greater than in the control group on days 3 to 5, and collagen deposition in the TGS-treated group was higher than in the control group during wound healing. The results indicate a beneficial effect of TGS when used to treat skin wounds.

Temporal Induction of Secretory Leukocyte Protease Inhibitor (SLPI) in Odontoblasts by Lipopolysaccharide and Wound Infection

INTRODUCTION The secretory leukocyte protease inhibitor (SLPI) is a bacterial lipopolysaccharide (LPS)-induced product of macrophages that antagonizes the LPS-induced activation of a number of proinflammatory signaling factors. From our previous experiments, it was found that SLPI was expressed slightly in odontoblast-like cells (MDPC-23). Therefore, these experiments were designed to determine the function of SLPI in MDPC-23 and odontoblasts during the inflammatory response caused by infections and wounds. METHODS MDPC-23 cells were exposed to 100 ng/mL Escherichia coli LPS, and artificial wounds were induced in the right first molar of the maxillary of rats. In addition, a morphological change in the MDPC-23 cells was observed after LPS treatment. MDPC-23 cells were transfected transiently with the nuclear factor kappa-B (NF-kappaB) promoter binding vector. RESULTS The level of SLPI expression increased strongly 30 minutes after the LPS treatment. Scanning electron microscopy revealed many extensions of the cytoplasmic processes after LPS stimulation. SLPI was expressed along the dentinal tubules and odontoblasts layer in rat teeth after an artificial wound. SLPI also inhibited the LPS-induced activation of NF-kappaB in MDPC-23. CONCLUSIONS We report for the first time that SLPI is expressed temporally in infected odontoblasts and may participate in the anti-inflammatory response through NF-kappaB signaling in odontoblast-like cells.

Expression of thymosin β4 in odontoblasts during mouse tooth development

Thymosin β4 (Tβ4) is expressed in developing tissue, where it stimulates cell differentiation and migration. Further, Tβ4 is expressed during molar development in mice, but the expression and function of Tβ4 in odontoblasts during mammalian tooth development have not yet been reported. Therefore, this study examined the expression and function of Tβ4 in differentiating odontoblasts during tooth development. As observed by immunohistochemistry, Tβ4 was expressed in the oral epithelium and inside cells of the tooth bud on embryonic day 15 (E15). Further, on E17, Tβ4 was expressed strongly in the dental lamina and oral epithelium, but only expressed in part of the cells in the outer and inner dental epithelium. Tβ4 was strongly expressed in the entire cytoplasm of odontoblasts on postnatal day 1 (PN1) and expressed intensively in the apical area of odontoblasts on PN4. Further, expression of Tβ4 was increased gradually in odontoblasts from PN1 to PN21. In an odontoblast cell line, MDPC-23, expression of Tβ4 mRNA and protein was increased strongly on day 4 and gradually decreased from day 14. The gene expression of dentin sialophosphoprotein (DSPP), bone sialoprotein (BSP), osteocalcin (OCN), osteonectin (ON), and collagen type I, related with mineralization, was significantly decreased in si-Tβ4/MDPC-23 during differentiation compared to that in MDPC-23 cells. Taken together, our results suggest that Tβ4 may be involved in oral epithelial cell proliferation at the initial stage of tooth development and regulates the expression and secretion of proteins during odontoblast differentiation.

Effect of secretory leukocyte protease inhibitor on migration and invasion of human KB oral carcinoma cells

Secretory leukocyte protease inhibitor (SLPI) plays an important role in promoting the invasion and metastasis of a range of cancer cells. However, there are no reports of the expression and function of SLPI in oral carcinoma cells. In this study, the oral carcinoma cell line KB was used to determine whether SLPI affects the proliferation, migration and invasion of oral carcinoma cells. RT-PCR and Western blotting revealed high levels of endogenous SLPI expression in KB cells as well as a strong increase in SLPI secretion after wounding compared to immortalized normal oral keratinocytes (INOK). The wound healing assay revealed more migration of KB cells than INOK cells, and the SLPI treatment increased the migration of KB cells. KB cell proliferation was increased significantly by the SLPI protein but decreased by SLPI-siRNA. SLPI strongly increased the migration and invasion of KB cells. On the other hand, SLPI-siRNA decreased the migration and invasion of KB cells. This suggests that SLPI plays an important role in the metastasis of oral carcinoma cells.

Induction of secretory leukocyte protease inhibitor (SLPI) in estradiol valerate (EV) induced polycystic ovary

The excessive administration of estradiol valerate induces polycystic ovary syndrome by formation of follicular cysts. Secretory leukocyte protease inhibitor (SLPI) promotes wound healing by decreasing the excessive inflammatory response, stimulating keratinocyte proliferation and increasing collagen deposition through the inhibition of protease activity. In this study, SLPI expression was high in the ovarian stroma, corpus luteum, unilaminar primary follicle, multilaminar primary follicle and granulose layer of the antral follicle in polycystic ovary (PCO) compared to the normal ovary. SLPI was expressed strongly in the theca around the cyst in PCO compared to the mature follicle in the normal ovary. The levels of SLPI mRNA and protein expression were higher in PCO than in the normal ovary, and the level of MMP-2 expression was lower in PCO. These results showed that the formation of a cyst was initiated from a multilaminar primary follicle and SLPI expression was increased depending on the morphological changes in the follicle and ovarian stroma. Therefore, an increase in SLPI may be related to the suppression of tissue disruption, and act as a protease inhibitor in PCO, suggesting that SLPI increases independently of the estrogen concentration in pathological tissues.

Comparative Ultrastructure of Secretory Granules of the Submandibular Gland in the Korean Spider Shrew, Sorex caecutiens, the Lesser White-toothed Shrew, Crocidura suaveolens and the Big White-toothed Shrew, Crocidura lasiura

The ultrastructure of the secretory granules of the submandibular gland was examined in the Korean spider shrew, Sorex caecutiens, lesser white-toothed shrew, Crocidura suaveolens and big white-toothed shrew, C. lasiura. The mucous and serous acinar granules of S. caecutiens with a border of the lucid corona differed from those of C. suaveolens and C. lasiurar with a dense lateral border. The mucous acinar granules of C. lasiura with several bands producing a variety of patterns in the matrix were similar to those of C. suaveolens. The serous acinar granules of C. lasiura had a homogenous pale center surrounded by minute dense specks or had an unusual substructure showing a geometric pattern according to the inclusions in the pale matrix of the granules. This is the first report of an unusual substructure showing a geometric pattern of the serous acinar granules of C. lasiura. The myelin-like body was observed in the granular duct cell of the three species of shrew. The myelin-like body of S. caecutiens with layers of unit membranes was different from that of C. suaveolens and C. lasiura with paired membranes. Therefore, the layers composing of the paired membranes of the myelin-like body might be one of the characteristics of Crocidura.

Thymosin β4 Reduces H2O2 Induced Oxidative Stress in MC3T3-E1 Cells on Titanium Surface

Thymosin β4 (Tβ4) is known to inhibit an inflammatory response and to increase the survival of osteoblasts on titanium (Ti) surfaces. Ti is the most widely used graft material in dentistry; however, an inflammatory response induced following implant placement results in the generation of reactive oxygen species (ROS). The oxidative stress from the production of ROS such as nitric oxide (NO) and hydrogen peroxide (H2O2) can damage surrounding cells, resulting in implant failure by decreasing cell viability. Thus, the aim of this study was to determine the biological effects of Tβ4 on the oxidative stress induced to MC3T3-E1 preosteoblasts on the Ti surface. Based on an MTT assay and bromodeoxyuridine immunofluorescence staining, Tβ4 was found to increase the proliferation of the H2O2-exposed MC3T3-E1 cells on Ti discs. Reverse transcription-polymerase chain reaction and western blot analyses showed that Tβ4 decreased the mRNA and protein expression levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in H2O2-exposed MC3T3-E1 cells on the Ti discs. Tβ4 inhibited the synthesis of intracellular ROS and the secretion of NO and prostaglandin E2 (PGE2) from H2O2-exposed MC3T3-E1 cells on the Ti discs. In conclusion, Tβ4 inhibits H2O2-induced iNOS and COX-2 expression with a decrease in ROS, NO, and PGE2 synthesis, which leads to improved cell survival with low cytotoxicity under an oxidative stress condition in MC3T3-E1 cells on the Ti surface. This suggests that Tβ4 may be a crucial molecule to reduce oxidative stress-induced cell damage or hypoxia, leading to promoted osseointegration on the Ti surface during implant placement.

Effect of Pycnogenol on Skin Wound Healing

This study was carried out to investigate the effects of pycnogenol (PYC) on the cutaneous wound healing of the mice. The wounds were extracted on days 1, 3, 5, and 7 post-injury for histomorphometrical analysis including wound area, infiltrating inflammatory cells, wound contracture including colla...

Increase of Grb2 and Ras Proteins and Expression of Growth Factors in LPS Stimulated Odontoblast-like Dental Pulp Cells

Inflammatory cells express the inflammatory cytokines and growth factors induced by lipopolysaccharide (LPS). Odontoblasts are located at the pulp-dentin interface and extend their cell processes far into the dentin where they are the first cells to encounter microorganisms or their products. Therefore, this study examined the expression of some growth factors related to the signal pathway, such as growth factor receptor binding protein 2 (Grb2)-Ras in odontoblast-like dental pulp cells, after a treatment with LPS. After 60 minutes, the mRNA and protein expression levels of Grb2 and Ras were higher in the LPS-treated cells than in the control cells. The level of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) mRNA expression was increased significantly to a level similar to that of Grb2 and Ras at 60 minutes. The platelet-derived growth factor-AA (PDGF-AA) mRNA level was expressed strongly in the odontoblast like dental pulp cells without an association with LPS stimulation. Scanning electron microscopy revealed many extensions of the cytoplasmic processes and the number of processes increased gradually at 30, 60 and 90 minutes after LPS stimulation. From these results VEGF and bFGF expression might be induced through the Grb2-Ras signal transduction pathway in LPS treated odontoblasts.