Products of dentin matrix protein-1 degradation by interleukin-1β-induced matrix metalloproteinase-3 promote proliferation of odontoblastic cells

Recombinant human dentin matrix protein 1 (DMP1) induces the osteogenic differentiation of human periodontal ligament cells

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Recombinant human dentin matrix protein 1 (DMP1) can be produced in Escherichia coli.

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E. coli produced DMP1 could induce the expression of osteogenic-related genes and calcium deposition in human PDL cells.

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This protein has potential to use for improving tooth repair and regeneration in the future.

The study aimed to produce recombinant human dentin matrix protein 1 (DMP1) and to test, whether the recombinant DMP1 produced in Escherichia coli possesses functional activity. A gene construction comprising a gene encoding for DMP1 protein with polyhistidine sequence at its C-terminus was created using the pET22b plasmid and expressed in E. coli. The optimization of cultivation conditions has enabled the induction of the gene expression with 0.5 mM isopropyl β-D-1-thiogalactopyranoside (IPTG) and DMP1 recombinant protein production at 37 °C for 6 h. The recombinant protein was purified using Ni affinity chromatography. DMP1 influence on the viability, osteogenic differentiation and calcification of human periodontal ligament (PDL) cells was examined. The purified DMP1 could induce the expression of osteogenesis related genes and calcium deposition in PDL cells. These findings indicate that DMP1 produced in E. coli can induce the osteogenic differentiation of human PDL cells, leading to improved tooth repair and regeneration.

Functional Roles of NOD1 in Odontoblasts on Dental Pulp Innate Immunity

Caries-related pathogens are first recognized by odontoblasts and induce inflammatory events that develop to pulpitis. Generally, initial sensing of microbial pathogens is mediated by pattern recognition receptors, such as Toll-like receptor and nucleotide-binding oligomerization domain (NOD); however, little is known about NODs in odontoblasts. In this study, the levels of NODs expressed in rat odontoblastic cell line, KN-3, were assessed by flow cytometry and the levels of chemokines in NOD-specific ligand-stimulated KN-3 cells were analyzed by real-time PCR and ELISA. The signal transduction pathway activated with NOD-specific ligand was assessed by blocking assay with specific inhibitors and reporter assay. In KN-3 cells, the expression level of NOD1 was stronger than that of NOD2 and the production of chemokines, such as CINC-1, CINC-2, CCL20, and MCP-1, was upregulated by stimulation with NOD1-specific ligand, but not with NOD2-specific ligand. CINC-2 and CCL20 production by stimulation with NOD1-specific ligand was reduced by p38 MAPK and AP-1 signaling inhibitors. Furthermore, the reporter assay demonstrated AP-1 activation in NOD1-specific ligand-stimulated KN-3 cells. These findings indicated that NOD1 expressed in odontoblasts functions to upregulate the chemokines expression via p38-AP-1 signaling pathway and suggested that NOD1 may play important roles in the initiation and progression of pulpitis.

Chinese medicine as complementary therapy for female infertility

Chinese medicine (CM) has been used in clinical treatment for thousands of years in China, Japan, Korea, and other countries. CM is at present attracting many attentions around the world for reproductive health care and disease prevention, including treatment of female infertility. This review focuses on the CM treatment for female infertility patients, and supplies a summary on the efficacy, safety, and mechanism of some Chinese herbal medicines, herbal medicine-derived active compounds, and acupuncture. A large number of researches have reported that CM could alleviate or even cure female infertility by regulating hormone, improving reproductive outcome of in vivo fertilization, affecting embryonic implantation, curing polycystic ovarian syndrome, endometriosis, pelvic inflammatory disease, relieving mental stress, and regulating immune system. Meanwhile, a few studies claimed that there was little adverse reaction of CM in randomized controlled trials. However, up to present there is a lack of adequate evidences with molecular mechanistic researches and randomized controlled trials to prove the CM as an effective and safe treatment for infertility. Thus, utility of CM as a complementary medicine will be a feasible method to improve the outcome of female infertility treatment.