Insect cuticle or exoskeleton is an extracellular matrix consisting of three major morphologically distinct layers, the water-proofing envelope, the protein-rich epicuticle and the chitin/protein-rich procuticle. To accommodate growth, insects must periodically replace their cuticles in a process called “molting or ecdysis”. During each molt cycle a new cuticle is deposited simultaneously with degradation of the inner part of the chitinous procuticle of the old one by molting fluid enzymes including epidermal chitinases. In this study, we show a novel role for an epidermal endochitinase containing two catalytic domains, TcCHT7, from the red flour beetle, Tribolium castaneum, belonging to a subfamily (group III) of insect chitinases in organizing chitin in the newly forming cuticle rather than in degrading chitin present in the prior one. RNAi of TcCHT7 reveals that this enzyme is nonessential for any type of molt or degradation of the chitinous matrix in the old cuticle. In contrast, TcCHT7 is required for formation of properly oriented long chitin fibers inside pore canals that are vertically oriented columnar structures, which contribute to maintain the integrity and the mechanical strength of a light-weight, yet rigid, adult cuticle. Because group III chitinases are highly conserved among insect and other arthropod species, these enzymes have a critical role in the higher ordered organization of chitin fibers for development of the structural integrity of many invertebrate cuticular extracellular matrices. This work was supported by NRFs (NRF-2015R1A2A2A01006614 and NRF-2018R1A2B6005106)

To accommodate growth, insects must periodically replace their chitin/protein-rich cuticles in a process called “molting or ecdysis”. During each molt cycle, a new cuticle is deposited simultaneously with degradation of the chitinous procuticle of the old one by molting fluid enzymes including epidermal chitinases. Here, we demonstrated a novel role for an endochitinase, TcCHT7, from the red flour beetle, Tribolium castaneum, belonging to a subfamily (Group III) that contain two catalytic domains, in organizing chitin in the newly forming cuticle rather than in degrading chitin present in the prior one. The conservation of CHT7-like proteins among many insect and other arthropod species indicates a critical role for the Group III class of chitinases in the higher ordered organization of chitin fibers for development of the structural integrity of many invertebrate exoskeletons.

The salivary gland undergoes complex process of growth and differentiation of the branching morphogenesis of ductal system during the prenatal and early postnatal periods which are regulated by various elements in the extracellular matrix. Extracellular matrix metalloproteinase inducer (EMMPRIN) is a cell adhesion molecule. In the present study, localization and expression of EMMPRIN in development and effects of chorda-lingual denervation and cyclosporine A (CsA) treatment on the EMMPRIN expression were investigated. Immunohistochemistry, RT-PCR and Western blot were used to determine expression level. Immunohistochemistry revealed that EMMPRIN was localized specifically in the cytoplasm of ductal cells, not acini of the submandibular gland all the postnatal periods. At prenatal day 18, when the formation of ducts was not definite, no immunoreactivity was observed. Both Western blot and RT-PCR analyses revealed that EMMPRIN expression was maintained up to postnatal day 7, decreased after postnatal day 10. The EMMPRIN expression was upregulated by the surgical denervation of the chorda-lingual nerve in the gland as well as by the CsA treatment. The present study suggests that EMMPRIN is a crucial molecule for maintaining physiological functions of the salivary gland.

Sambucus sieboldiana (SS) is a member of the family Caprifoliaceae and has been recommended as a functional material because of its several bioactivities. Although numerous literatures are available on the pharmacological and biological activities, the biological activity of SS in bone regeneration process has not yet been well-defined. Therefore, in this study, the effect of SS was investigated in the proliferation and differentiation of MC3T3-E1 osteoblastic cell line. The treatment of SS did not significantly affect the cell proliferation in MC3T3-E1 cells. SS significantly accelerated the mineralization and significantly increased the expression of alkaline phosphatase (ALP) and osteocalcin (OC) mRNAs, compared to the control, in the differentiation of MC3T3-E1 cells. SS significantly accelerated the decrease of osteonectin (ON) mRNA expression as compared with the control in a time-dependent manner in the differentiation of MC3T3-E1 cells. These results suggest that the SS facilitate the osteoblast differentiation and mineralization in MC3T3-E1 osteoblastic cells. Therefore, there may be potential properties for development and clinical application of bone regeneration materials.

Matrix metalloproteinases (MMPs) have been known to affect to cell migration, proliferation, morphogenesis and apoptosis by degrading the extracellular matrix. In the previous studies, undifferentiated mouse embryonic stem cells (ESCs) were successfully proliferated inside the extracellular matrix (ECM) analog-conjugated three-dimensional (3D) poly ethylene glycol (PEG)-based hydrogel. However, there is no report about MMP secretion in ESCs, which makes it difficult to understand and explain how ESCs enlarge space and proliferate inside 3D PEG-based hydrogel constructed by crosslinkers containing MMP-specific cleavage peptide sequence. Therefore, we investigated what types of MMPs are released from undifferentiated ESCs and how extracellular signals derived from various niche conditions affect MMP expression of ESCs at the transcriptional level. Results showed that undifferentiated ESCs expressed specifically MMP2 and MMP3 mRNAs. Transcriptional up-regulation of MMP2 was caused by the 3D scaffold, and activation of integrin inside the 3D scaffold upregulated MMP2 mRNAs synergistically. Moreover, mouse embryonic fibroblasts (MEFs) on 2D matrix and 3D scaffold induced upregulation of MMP3 mRNAs, and activation of integrins through conjugation of extracellular matrix (ECM) analogs with 3D scaffold upregulated MMP3 mRNAs synergistically. These results suggest that successful proliferation of ESCs inside the 3D PEG-based hydrogel may be caused by increase of MMP2 and MMP3 expression resulting from 3D scaffold itself as well as activation of integrins inside the 3D PEG-based scaffold.

The pattern of wound healing process differs markedly according to the cell types. Gingival wounds heal more rapidly without scar, however dermal wounds show collagen laid down in thick disorganized patterns and keloid formation. This h as b een s uggested t o be d ue t o the presence of d ifferent E C M components a nd c ytokines a s well a s growth factors. The purpose of this study was to examine the differential expression of genes in connection with keloid formation in gingival fibroblasts (hGFs) and dermal fibroblasts (hDFs) in response to inflammation. In this study, we investigated the differences between hGFs and hDFs in the expression and production of cyclooxygenase (COX-2), prostaglandins E2 (PGE2), transforming growth factor (TGF)-β, collagens, matrix metalloproteinases (MMPs), and tissue inhibitors of matrix metalloproteinases (TIMPs) which play important roles in collagen deposition in wound healing. The hGFs and hDFs were primary cultured and allocated to arachidonic acid (AA) treatment group and control group. Protein and mRNA were extracted right after (0 hr) and 24 hr after AA treatment. At a defined concentration of AA in hGFs and hDFs, MTT assay was performed. The mRNA and protein expression levels of COX-2, TGF-β, collagen 1 and 3, MMP 1 and TIMP 1 were examined by Real-time PCR and Western blots. The amounts of PGE2 were measured by enzyme-linked immunosorbent assay (ELISA).The expression of COX-2 and TGF-β exhibited reduced levels in hGFs , but were increased in hDFs at 24 hr after AA treatment. Production of PGE2 was increased in hGFs and hDFs at right after AA treatment but, not changed at 24 hr after AA treatment. The protein and mRNA expression of collagen 1 and 3 were decreased in hGFs , whereas increased in hDFs at 24 hr AA treatment. Expression of MMP-1 protein was increased in hGFs at 24 hr but, was decreased in hDFs at 24 hr compared with that of control. The protein expression of TIMP-1 was decreased in hGFs but, was increased in hDFs at 24 hr compared with that of control. These observations demonstrate differential expression between gingival and dermal fibroblasts in regulation of collagenolytic capacity by extracellular matrix-associated genes in keloid formation associated with wound repair.

It has been reported that light-emitting diodes(LED) can be used in the treatment of oral diseases. Although bio-stimulatory effects of LED irradiation such as promotion of wound healing have been well known, there are few reports about molecular mechanisms associated with wound healing by LED irradiation. The purpose of the present study was to investigate the expression pattern of various extracellular matrix(ECM) molecules in relation to wound healing after LED irradiation on primary human gingival fibroblasts(hGFs) in vitro. The source of light for irradiation was a continuous-wave LED emitting at a wavelength of 635 nm, and manufactured that energy density was 5 mW/cm2 on sample surfaces. The hGFs were irradiated for 1 hour at 37℃ in 5% CO2 humidified chamber. Experimental samples were acquired at 0 (right after irradiation), 24 and 48 hour after irradiation. To investigate the molecular mechanisms associated with wound healing, we examined the mRNA expression of 6 types of collagens, 7 types of matrix metalloproteinases(MMPs) and 4 types of tissue inhibition of metalloproteinases(TIMPs) after LED irradiation by RT-PCR. The mRNA expression of collagen 4, MMP-3, 9, and 16, and TIMP-3 was influenced by LED irradiation. Generally, the collagen expression of the irradiation group was slightly increased, particularly collagen 4 was significantly increased at 0 hour. The expression of MMP-3 was increased at 0 and 24 hours and MMP-16 was increased at 24 hours, respectively. The expression of MMP-9 was decreased at 0 hour and increased at 24 and 48 hours. The mRNA expression of TIMP-3 was significantly decreased at 24 and 48 hours after irradiation. These results suggest that the altered expression of ECM molecules after LED irradiation may contribute to the accelerated wound healing.

To investigate the effect of extracellular matrix proteins on the in vitro development of ethanol-induced parthenogenetic eggs of ICR strain mice, those were cultured in vitro in fibronectin, gelatin, or collagen precoated culture dishes containing 1.5 ml of NaH-C03-BMOC-3 medium at 37 for 96 hrs. under the atmosphere of 5% and 95% air. Fibronectin, gelatin, or collagen significantly(P1.4, 45.4i1.4, and 44.8O.9, respectively. And the diameter of those eggs ranged 104.61.9, 102.82.3, and 103.4O.8 m, respectively.

Adipogenesis is a primary energy valancing response in physiological status and critical in embryo development. One of the essential factors for initiation and maintaining of adipogenesis is the composition of extracellular matrix. Previously, we confirmed the effects of diphlorethohydroxycarmalol (DPHC), an extract of Ishige okamurae, on the antiobesity effects and ECM stability in adipose tissue. In vitro model for adipogenesis study, 3T3-L1, a precursor cell type of adipocyte, and the adipose-tissue derived stem cell (ADSC) can be used. Usually the induction period for adipocyte is shorter in 3T3-L1 than in ADSCs. However, so far, the difference of the expression patterns of ECM components in 3T3-L1 and ADSCs, and the effects of DPHC are not much known. We induced differentiation of 3T3-L1 and ADSCs into adipocyte with or without DPHC (0, 0.4, 2, 10, 50 μg/mL) and confirmed the adipogenesis with adipogenic markers (PPAR-γ, LDL). After then, the levels of collagen type 1 alpha 1 (Col1a1), collagen type 3 alpha 1 (Col3a1), collagen type 4 (Col4), collagen type 6 (Col6), Elastin (Eln) and microfibrillar associated protein 5 (Mfap5) were analyzed with real-time RT-PCR. During early adipogenesis of ADSC, the expression levels of Col1, Col3, Col6, and Mfap5 mRNA were decreased but Col4 and Eln mRNA were increased. In the matured adipocyte, the expression levels of Col1, Col3, Col4, Mfap5 mRNA were decreased but not Eln. In the case of early differentiation of 3T3-L1, the expression levels of Col1, Col3, Eln mRNA were decreased but the expression levels of Col6 and Mfap5 were increased. In matured adipocyte of 3T3-L1, the expression levels of Col1, Col3, Eln, Mfap5 mRNA were increase but the expression level of Col6 mRNA was decreased. The expression levels of Col4, Eln mRNA were suppressed by 50 mg/mL DPHC treatment during early adipogenic period of ADSC. On the other hand in 3T3-L1, the expression levels of Col3 and Col6 mRNA were not changed by the DPHC treatment during early induction period. In the matured adipocytes derived from ADSC, Col1 mRNA levels was not decreased by the treatment of 50 mg/mL DPHC. Col4 mRNA levels was not increased by DPHC treatment. In the case of matured adipocytes derived from 3T3-L1, DPHC suppressed the increase of Col1, Col3, Col6 mRNA expression and the expression of Col4 and Eln mRNA was decreased. In summary, these data show that expression levels of each ECM component types are dramatically changed with some common patterns in two cell types, and the treatment of DPHC can modify the expression patterns of some ECM components in each cell types. It is suggested that one of the reason of antiadipogenic effect of DPHC may be the ECM modification.

포유동물의 난포내 난자의 성숙 시에는 난자를 둘러싸고 있는 난구세포의 확장 현상이 일어나는데 이 현상에는 hyaluronic acid 뿐만 아니라 다른 성분도 관여하는 것으로 알려져 있다. 본 연구는 조직 재구성 과정에서 중요한 역할을 하는 matrix metalloproteinase(MMP)가 사람의 성숙한 난자-난구 복합체의 extracellular matrix(ECM)에 존재하는지의 여부를 알아보고자 하였다. 체외수정 시술 시에 얻어지는 사람의 난