[Regulation of microRNA-126 on the polarization of human macrophages stimulated by Porphyromonas gingivalis lipopolysaccharide].

Objective: To study the effect of microRNA-126 (miR-126) on the polarization of human monocyte-derived macrophages stimulated by Porphyromonas gingivalis (Pg) lipopolysaccharide (LPS). Methods: Macrophages derived from human myeloid leukemia mononuclear cells were stimulated by Pg-LPS (5 mg/L) and by Pg-LPS (5 mg/L) after 24 h-transfection of miR-126 mimic or negative control RNA for 48 h, respectively. Real-time quantitative-PCR (qRT-PCR), enzyme-linked immunosorbent assay (ELISA) and Western blotting were conducted to detect the changes in miR-126, pro-inflammatory factor tumor necrosis factor-α (TNF-α), anti-inflammatory factors interleukin-10 (IL-10), inducible nitric oxide synthase (iNOS), arginase-1 (Arg-1) and M1 polarization-related pathways such as nuclear factor kappa-B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways. Results: Compared with non-LPS stimulation group (TNF-α: 1.000±0.020, iNOS: 1.125±0.064, miR-126: 1.004±0.113, IL-10: 1.003±0.053, Arg-1: 1.130±0.061), the mRNA levels of TNF-α (3.105±0.278) and iNOS (4.296±0.003) increased significantly (t=6.53, P=0.003; t=42.63, P<0.001, respectively), while miR-126, IL-10 and Arg-1 expressions (0.451±0.038, 0.545±0.004 and 0.253±0.017) decreased significantly (t=7.95, P=0.001; t=7.36, P=0.002; t=11.94, P<0.001, respectively) after Pg-LPS stimulated by human-derived macrophages for 48 h. The protein expression of iNOS, TNF-α, Arg-1 and IL-10 were consistent at mRNA levels. Meanwhile, the expressions of phospho-NF-κB p65 (p-p65), phospho-extracellular signal-regulated kinase (p-ERK) and phospho-p38 MAPK (p-p38) increased significantly, while the expression of Arg-1 decreased significantly. Compared with the negative controls (scramble RNA) (TNF-α: 1.141±0.197, iNOS: 1.173±0.115, IL-10: 1.032±0.138, Arg-1: 0.933±0.044), the mRNA levels of TNF-α (0.342±0.022) and iNOS (0.588±0.085) expressions significantly decreased (t=5.35, P=0.006; t=5.05, P=0.007), while IL-10 (1.786±0.221) and Arg-1 expressions (2.152±0.229) significantly increased (t=3.71, P=0.021; t=6.21, P=0.003) after Pg-LPS stimulation with miR-126 mimic transfection. The relative protein expressions of iNOS, p-p65, p-ERK and p-p38 significantly decreased (t=13.00, P<0.001; t=6.98, P=0.002; t=10.86, P<0.001; t=8.32, P=0.001), while the protein level of Arg-1 significantly increased (t=12.08, P<0.001). Conclusions: Pg-LPS could promote M1 polarization of macrophages. miR-126 might inhibit the effect of Pg-LPS on the M1 polarization of macrophages through down-regulating NF-κB and MAPK signaling pathways.

[microRNA-146a reverses the inhibitory effects of Porphyromonas gingivalis lipopolysaccharide on osteogenesis of human periodontal ligament cells].

Objective: To investigate the effects and mechanisms of microRNA-146a (miR-146a) on osteogenic differentiation of human periodontal ligament cells (hPDLC) stimulated by lipopolysaccharide (LPS) of Porphyromonas gingivalis (Pg). Methods: hPDLC were cultured in vitro and induced to the phase of osteogenic differentiation. These cells were divided into five groups: non-osteogenic differentiation cells, osteogenic differentiation cells, osteogenic differentiation cells treated with Pg LPS, osteogenic differentiation cells treated with Pg LPS and miR-146a mimic, osteogenic differentiation cells treated with Pg LPS and miR-146a negative control. Osteogenic markers and mineralization were detected via quantitative real-time PCR (qPCR) and alizarin red staining, respectively. Meanwhile, non-radioactive transcription factor assay was applied to explore the nuclear activity of nuclear factor kappa B (NF-κB) p65 in nuclear extracts of hPDLC. Results: Compared with cells of osteogenic differentiation in non-LPS-stimulated groups, Pg LPS could decrease the markers of osteogenic differentiation of hPDLC such as collagen Ⅰ (Col-Ⅰ), alkaline phosphatase (ALP), Runt-related transcription factor-2 (RUNX2) and osteocalcin (OCN) (P<0.05), inhibit mineralization, and stimulate NF-κB p65 nuclear activity expression (non-LPS stimulated group: 1.023±0.217, LPS stimulated group: 6.252±0.613, P=0.008). However, compared with cells in Pg LPS/miR-146a negative control group, miR-146a increased Col-Ⅰ (P=0.007) and OCN (P=0.049) mRNA expression, rather than ALP (P=0.167) and RUNX2 (P=0.580) at day 3; miR-146a also upregulated mRNA levels of Col-Ⅰ, ALP, RUNX2 and OCN (P<0.05) at day 7 and day 14, and enhance mineralization. Meanwhile, miR-146a mimic could decrease the nuclear activity of NF-κB p65 induced by Pg LPS in hPDLC (miR-146a: 2.427±0.354, negative control: 5.863±0.482, P=0.019). Conclusions: miR-146a could reverse the inhibitory effects of Pg LPS on osteogenic differentiation of hPDLC through enhancing the expression of osteogenic markers and decreasing inflammatory pathway in hPDLC.

[Expression profile of long non-coding RNA in gingival tissues from the patients with aggressive periodontitis].

Objective: To detect and analyze the differential expression profile of long non-coding RNA (lncRNA) in aggressive periodontitis (AgP) and healthy gingival tissues, in order to explore the role of lncRNA in AgP. Methods: After the informed consents were obtained, gingival tissues from AgP patients (n=40) and healthy volunteers (n=40) were collected in Department of Periodontology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine (from Mar. 2012 to Aug. 2012) and Department of Periodontology, Hospital of Stomatology, Tianjin Medical University (from Oct. 2016 to Apr. 2017). The differential expression of lncRNA of tissues from AgP patients (n=20) and healthy volunteers (n=20) were examined via microarray assay. Bioinformatics was applied to analyze the expression data of lncRNA and correlative mRNA. Two lncRNAs (lncRNA-TNFRSF13C and lncRNA-API5) were chosen to verify the microarray results by using real time quantitative polymerase chain reaction (PCR) in the other gingival tissues. Results: Compared with the result of healthy gingival tissues, totally 8 632 lncRNAs were differentially expressed in tissues from AgP patients. From these data, 1 986 lncRNAs were significantly upregulated while 6 646 lncRNAs were downregulated, amongst which 48 lncRNAs were upregulated (>10 times) (P<0.05), 14 lncRNAs were downregulated (>10 times) (P<0.05). Furthermore, totally 5 519 correlative mRNAs were differentially expressed, amongst which 1 676 mRNAs were upregulated (≥2 times, P<0.05) and 3 843 mRNAs were downregulated≤0.5 (P<0.05). The selected lncRNA-TNFRSF13C and lncRNA-API5 were up-regulated in AgP (P<0.05), which confirmed the results of microarray. From bioinformatics, differential expression lncRNAs were in association with many signal pathways including toll-like receptor signaling pathway, cell cycle and apoptosis pathway, and tumor necrosis factor receptor superfamily pathway. Conclusions: LncRNA may be involved in the pathogenesis of AgP through various pathways, which need to be further explored.

Photodynamic killing of human squamous cell carcinoma cells using a monoclonal antibody-photosensitizer conjugate.

We have developed procedures in which the photosensitizer benzoporphyrin derivative monoacid ring A (BPD) can be covalently linked to carrier molecules of modified polyvinyl alcohol (PVA) to produce water-soluble PVA-BPD conjugates with a molecular mass in the range of 30 kd. These carriers can subsequently be covalently linked to monoclonal antibodies (MoAbs) using heterobifunctional linking agents. We describe here such a conjugate in which the MoAb (5E8) has specificity for a glycoprotein detected on human squamous cell carcinomas of the lung. We provide evidence that the conjugates produced were covalently linked and retained both their photosensitizing and antigen-binding activities. We show further that the MoAb-PVA-BPD conjugate, in the presence of 10% fetal calf serum, exhibited highly enhanced phototoxic killing of the target cell line (A549) over that exhibited by free BPD or a control MoAb-PVA-BPD conjugate. These results demonstrate, therefore, both the selectivity and specificity of this MoAb conjugate.

Modified polyvinyl alcohol-benzoporphyrin derivative conjugates as phototoxic agents.

Photosensitizing and biodistribution characteristics of a photosensitizer (benzoporphyrin derivative, monoacid ring A; BPD) conjugated to a macromolecule (modified polyvinyl alcohol; M-PVA, molecular weight = 10,000) were tested in vitro and in vivo. Modified PVA was loaded with BPD at molar ratios 1:12, 1:25, 1:50, 1:75 and 1:100. Most of the work was carried out with a conjugate having a 1:25 molar ratio. In vitro photosensitization was tested using A549 (human lung carcinoma), A432 (human epidermoid carcinoma) and P815 (mastocytoma of DBA/2 mice) cell lines. Photosensitization of M1 (rhabdomyosarcoma of DBA/2 mice) tumors was tested in an in vivo/in vitro assay, in which tumor-bearing mice were injected intravenously with free or conjugated 3H-BPD and 3 h later light activation of tumor cells was carried out in vitro. Biodistribution studies were carried out using M1 tumor-bearing DBA/2 mice and 3H-BPD either free or conjugated to M-PVA. The results of these studies showed that the conjugation of BPD to M-PVA resulted in the formation of a macromolecular photosensitizer that retained full photosensitizing activity of the photosensitizer molecules and at the same time gained new characteristics, advantageous for photodynamic treatment, especially in vivo. In vitro M-PVA-BPD conjugates were at least as efficient in photosensitization of tumor cells as an equivalent number of free BPD molecules, both in the presence and in the absence of serum. Although the biodistribution was in general comparable to free BPD, the conjugate (1:25) reached slightly higher levels in the blood, kidney, lung and spleen, and lower levels in the liver, brain, skin and muscle in comparison with free BPD.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of enamel matrix proteins on proliferation, differentiation and attachment of human alveolar osteoblasts.

OBJECTIVES: Enamel matrix proteins (EMPs) have been demonstrated to promote periodontal regeneration. However, effects of EMPs on human alveolar osteoblasts (hAOBs), up to now, have still been unclear. The purpose of this study was to investigate influence of EMPs on proliferation, differentiation and attachment of hAOBs in vitro. MATERIALS AND METHODS: EMPs were extracted using the acetic acid method, hAOBs were obtained and cultured in vitro. Cell proliferation, alkaline phosphatase (ALP) activity, mRNA expression of osteogenic markers and cell attachment were measured in the absence and in the presence of EMPs (50, 100 and 200 µg/ml). RESULTS: EMPs increased proliferation of hAOBs; however, they inhibited ALP activity and mRNA expression of osteogenic markers (collagen I, ALP, runt-related protein 2, osteocalcin, bone sialoprotein and osteopontin). Meanwhile, EMPs hindered hAOBs' attachment. These effects occurred in EMPs concentration-dependent manner. CONCLUSIONS: These results indicate that EMPs may inhibit osteoblastic differentiation and attachment to prevent ankylosis and allow other cell types to regenerate periodontal tissues.

Age-related changes in biological characteristics of human alveolar osteoblasts.

OBJECTIVES: Age-related changes are common in many tissues and organs. However, cell-related causes in human alveolar bone remain unclear. This study has been carried out to explore the possibility that advancing age might change the biological characteristics of alveolar osteoblasts (AOBs) in women. MATERIALS AND METHODS: Alveolar osteoblasts from women donors (five women aged 33-38 years and five women aged 62-68 years) were cultured in vitro. The cells were serially passaged and maximal lifespan evaluated. Cell viability, ultramicrostructure and osteogenic differentiation ability were determined respectively, using MTT assay, transmission electron microscopy, alkaline phosphatase (ALP) activity assay and von Kossa staining assay. These parameters of the two groups of AOBs were evaluated. RESULTS: When compared with cells from young adult donors, AOBs from elderly women exhibited lower maximal lifespan (P < 0.05). Mean rate of population doubling was lower in elderly donor cells compared to those from young adult cells (P < 0.05). Organelles from AOBs of elderly donors were much fewer than those from young donors. MTT value of elderly donor cells was significantly lower than those of young adult donors from day 2 (P < 0.05). Relative ratio of ALP activity in elderly donor cells was significantly lower than those of the young womens' cells at 8, 12, 16 and 20 days (P < 0.05). Calcium nodules of young adult donors' specimens were significantly more numerous and larger than those from elderly donors. CONCLUSIONS: Comparison of biological characteristics of AOBs from young adult women with those from elderly women in vitro revealed differences in proliferative capacity and bone formation functions, which decreased with aging. These data indicate that aging may play an important role in pathogenesis of human AOBs loss.