SDF-1 modulates periodontal ligament-Mesenchymal Stem Cells (pdl-MSCs).

BACKGROUND/OBJECTIVES: In this in vitro study, the effects of Stromal cell-derived factor-1 (SDF-1) was evaluated on the periodontal ligament-Mesenchymal Stem Cells (pdl-MSCs) functions. MATERIAL AND METHODS: Real-time cell analyzer-single plate (RTCA-SP) was employed for proliferation, and RTCA-dual purpose (DP) was utilized for pdl-MSCs migration potential treated with different SDF-1 concentrations (0, 0.1, 1, 10, 100, 200, and 400 ng/ml). Based on the dose-response findings, 10 ng/ml SDF-1 was used for further mRNA experiments. RNAs isolated at 6 and 24 h were checked using quantitative RT-PCR for mineralized tissue-associated genes including type I collagen (COL I), osteocalcin (OCN), osteopontin (OPN), and runt-related transcription factor 2 (Runx2). cRNA was synthesized for 6 h, and whole-genome array analysis was performed for over 47.000 probes. Data were subjected to quantile normalization before analysis. RESULTS: Increased proliferation and migration were observed in pdl-MSCs treated with 0.1, 1, and 10 ng/ml SDF-1. Increased COL I was observed at both time points: 6 and 24 h. While there was no significant change for OCN, OPN, and Runx2 at 6 h, SDF-1 up-regulated OCN and OPN, but down-regulated Runx2 mRNA expressions at 24 h. IL-8 and ESM1 genes were differentially expressed over twofold when the pdl-MSCs were exposed to SDF-1 at whole-genome array analysis. IL-8 induction was confirmed with RT-PCR. CONCLUSION: Findings of this study displayed that SDF-1 modulated pdl-MSCs which were important for periodontal regeneration, inducing migration and proliferation, and regulating extracellular matrix synthesis in favor of the formation of new attachment.

Comparison of Different Sources of Mesenchymal Stem Cells: Palatal versus Lipoaspirated Adipose Tissue.

OBJECTIVES: The purpose of this study was to compare the proliferation and differentiation potential of mesenchymal stem cells (MSCs) derived from palatal adipose tissue (PAT) and lipoaspirated adipose tissue (LAT). MATERIALS AND METHODS: PATs were obtained from 2 healthy female patients undergoing surgery for gingival recession, and LATs were obtained from 2 healthy female patients undergoing plastic surgery. LAT- and PAT-derived MSCs were confirmed by flow cytometry using MSC-specific surface markers. The multilineage differentiation capacity of the MSCs was analyzed. The expression of immunophenotyping, embryonic, and differentiation markers was compared between both MSC lines. The proliferation of PAT- and LAT-MSCs was evaluated using a real-time cell analyzer, and telomerase activity was determined using an ELISA-based TRAP assay. Stem cells isolated from PAT and LAT were analyzed by real-time PCR and whole genome array analysis. RESULTS: The cells isolated from PAT had MSC characteristics. In addition, PAT-MSCs had significantly higher alkaline phosphatase activity and osteogenic potential than LAT-MSCs. Although the proliferation and telomerase activities of LAT-MSCs were higher than those of PAT-MSCs, the difference was not statistically significant. The level of embryonic stem cell markers (Oct4 and Nanog) was higher in LAT-MSCs than in PAT-MSCs. The whole genome array analysis demonstrated that 255 gene sequences were differentially expressed, with more than a twofold change in expression. CONCLUSIONS: This is the first comparative analysis of the isolation and characterization of MSCs from PAT and LAT. PAT is an accessible source of MSCs, which could be used in periodontal and craniofacial tissue engineering.

Porphyromonas gingivalis Lipopolysaccharide Induces a Pro-inflammatory Human Gingival Fibroblast Phenotype.

Human gingival fibroblasts (HGFs) are the major constituents of the gingival tissues responsible for the synthesis and degradation of the connective tissue while actively participating in immune reactions and inflammation. The aim of this study was to test the impact of lipopolysaccharide (LPS) from Porphyromonas gingivalis (P. gingivalis) on human gingival fibroblasts. Human gingival fibroblasts were treated with different P. gingivalis LPS concentrations. Cell survival rate was evaluated with 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) after 24 h. Cell proliferation was determined by counting cells on days 3 and 12. Expression of matrix metalloproteinases (MMPs), tissue inhibitors of MMPs (TIMPs), and pro-inflammatory cytokine transcripts in HGFs was determined by quantitative PCR (Q-PCR) analysis on days 3 and 8. P. gingivalis LPS decreased cell proliferation on day 3 (p < 0.05) compared to the control group without significantly impacting the cell survival (p > 0.05).The experiments showed that P. gingivalis LPS dose-dependently and differentially modulated the expression of MMP-1, 2, and 3 and TIMP-1 and 2 on days 3 and 8. TIMP-1 expression was significantly induced in P. gingivalis LPS-treated cells while TIMP-2 was increased in response to 10 and 30 ng/ml of LPS on day 3. P. gingivalis LPS induced up-regulation of MMP-1/TIMP-1 ratio on day 3 and increased MMP-2/TIMP-2 ratio on day 8 dose-dependently. Expression of interleukin (IL)-6 and IL-8 was stimulated at higher concentrations (1000 and 3000 ng/ml) of LPS. These findings demonstrate that P. gingivalis LPS suppresses cell proliferation and leads to increased pro-inflammatory changes in HGFs, suggesting that P. gingivalis LPS-induced modification of phenotypic and inflammatory characteristics in HGF could potentially be a pathogenic mechanism underlying the tissue destruction.

Comparison of mesenchymal stem cells isolated from pulp and periodontal ligament.

BACKGROUND: Cell-based therapy using mesenchymal stem cells (MSCs) seems promising to obtain regeneration of dental tissues. A comparison of tissue sources, including periodontal ligament (PDL) versus pulp (P), could provide critical information to select an appropriate MSC population for designing predictable regenerative therapies. The purpose of this study is to compare the proliferation and stemness and the MSC-specific and mineralized tissue-specific gene expression of P-MSCs and PDL-MSCs. METHODS: MSCs were obtained from PDL and P tissue of premolars (n = 3) extracted for orthodontic reasons. MSC proliferation was evaluated using a real-time cell analyzer for 160 hours. Telomerase activity was evaluated by a telomeric repeat amplification protocol assay based on enzyme-linked immunosorbent assay. Total RNA was isolated from the MSCs on day 3. A polymerase chain reaction (PCR) array was used to compare the expression of MSC-specific genes. The expression of mineralized tissue-associated genes, including Type I collagen (COL I), runt-related transcription factor 2 (RunX2), bone sialoprotein (BSP), and osteocalcin (OCN) messenger RNA (mRNA), was evaluated using quantitative real-time PCR. RESULTS: Higher proliferation potential and telomerase activity were observed in the P-MSCs compared to PDL-MSCs of premolar teeth. Fourteen of 84 genes related to MSCs were expressed differently in the PDL-MSCs versus the P-MSCs. The expressions of bone morphogenetic protein 2 (BMP2) and BMP6; sex-determining region Y-box 9 (SOX9); integrin, alpha 6 (ITGA6); melanoma cell adhesion molecule (MCAM); phosphatidylinositol glycan anchor biosynthesis, class S (PIGS); prominin 1 (PROM1); ribosomal protein L13A (RPL13A); and microphthalmia-associated transcription factor (MITF) were higher in the P-MSCs compared to the PDL-MSCs, and higher expression of matrix metalloproteinase 2 (MMP2), interleukin (IL)-6, insulin (INS), alanyl (membrane) aminopeptidase (ANPEP), and IL-10 were observed in the PDL-MSCs. However, there was no statistically significant difference in the expression of mineralized tissue-associated genes, including BSP and RunX2, between the P-MSCs and the PDL-MSCs. Higher expression of COL I and lower expression of OCN mRNA transcripts were noted in the PDL-MSCs compared to the P-MSCs. CONCLUSIONS: The results of this study suggest that MSCs isolated from P and PDL tissues show different cellular behavior. To increase the predictability of MSC-based regenerative treatment, differences in dental tissue-derived MSCs and favorable aspects of cell sources should be further clarified.

Bone morphogenetic protein-2, -6, and -7 differently regulate osteogenic differentiation of human periodontal ligament stem cells.

The utility of adult stem cells for bone regeneration may be an attractive alternative in the treatment of extensive injury, congenital malformations, or diseases causing large bone defects. To create an environment that is supportive of bone formation, signals from molecules such as the bone morphogenetic proteins (BMPs) are required to engineer fully viable and functional bone. We therefore determined whether BMP-2, -6, and -7 differentially regulate the (1) proliferation, (2) mineralization, and (3) mRNA expression of bone/mineralized tissue associated genes of human periodontal ligament stem cells (hPDLSCs), which were obtained from periodontal ligament tissue of human impacted third molars. hPDLSCs from six participants were isolated and characterized using histochemical and immunohistochemical methods. A real-time cell analyzer was used to evaluate the effects of BMP-2, -6, and -7 on the proliferation of hPDLSCs. hPDLSCs were treated with Dulbecco's modified Eagle's medium containing different concentrations of BMP-2, -6, and -7 (10, 25, 50, 100 ng/mL) and monitored for 264 hours. After dose-response experiments, 50 and 100 ng/mL concentrations of BMPs were used to measure bone/mineralized tissue-associated gene expression. Type I collagen, bone sialoprotein, osteocalcin, osteopontin, and osteoblastic transcription factor Runx2 mRNA expression of hPDLSCs treated with BMP-2, -6, and -7, were evaluated using quantitative RT-PCR. Biomineralization of hPDLSCs was assessed using von Kossa staining. This study demonstrated that BMPs at various concentrations differently regulate the proliferation, mineralization, and mRNA expression of bone/mineralized tissue associated genes in hPDLSCs. BMPs regulate hPDLSC proliferation in a time and dose-dependent manner when compared to an untreated control group. BMPs induced bone/mineralized tissue-associated gene mRNA expression and biomineralization of hPDLSCs. The most pronounced induction occurred in the BMP-6 group in the biomineralization of the hPDLSCs. Our data suggest that BMP-2, -6, and -7 are potent regulators of hPDLSC gene expression and biomineralization. Employing BMPs with hPDLSCs isolated from periodontal ligament tissues provides a promising strategy for bone tissue engineering.

Bone morphogenetic protein-7 enhances cementoblast function in vitro.

BACKGROUND: Bone morphogenetic protein (BMP)-7 is a potent bone-inducing factor and was shown to promote periodontal regeneration in vivo and in vitro; however, to our knowledge, the specific effect of BMP-7 on cementoblasts has not been defined. We aimed to investigate the effects of BMP-7 on cementoblasts, which are cells responsible for tooth root-cementum formation. We hypothesized that BMP-7 would regulate mineralized tissue-associated genes in cementoblasts and influence the expression profile of genes associated with cementoblast extracellular matrix (ECM) and cell adhesion molecules (CAMs). METHODS: A murine immortalized cementoblast cell line (OCCM.30) was cultured with and without 50 ng/ml BMP-7. After 72 hours, total RNA was isolated, and mRNA levels for bone/cementum markers, including bone sialoprotein (BSP), osteocalcin (OCN), osteopontin (OPN), and runt-related transcription factor-2 (Runx2), were investigated by real-time quantitative reverse transcription-polymerase chain reaction (Q-PCR). In vitro mineral nodule formation was assayed on day 8 using von Kossa staining. A pathway-specific gene-expression array was used to determine BMP-7-responsive ECM and CAM genes in cementoblasts. RESULTS: Mineralized tissue markers were strongly regulated by BMP-7, with an almost three-fold increase in BSP and OCN transcripts and significant increases in OPN and Runx2 mRNA expressions. BMP-7 treatment markedly stimulated cementoblast-mediated biomineralization in vitro compared to untreated cells at day 8. BMP-7 treatment altered the OCCM.30 expression profile for ECM and CAM functional gene groups. BMP-7 tended to increase the expression of collagens and matrix metalloproteinases (MMPs), mildly decreased tissue inhibitors of MMPs (TIMPs), and had mixed regulatory effects on integrins. Using Q-PCR, selected array results were confirmed, including a significant BMP-7-induced increase in MMP-3 and a decrease in TIMP-2 mRNA expression. CONCLUSION: These results support the promising applications of BMP-7 in therapies aimed at regenerating periodontal tissues lost as a consequence of disease.

Boron regulates mineralized tissue-associated proteins in osteoblasts (MC3T3-E1).

The aim of this study was to determine the effects of boron (B) on the cell-survival, proliferation, mineralization and mRNA expression of mineralized tissue-associated proteins. Additionally, determination of the effects of B on the BMP-4, -6 and -7 protein levels of pre-osteoblastic cells (MC3T3-E1) was also intended. The effects of B (pH 7.0) concentrations (0, 0.1, 1, 10, 100, 1000, 2000, 4000, 8000 and 10,000 ng/ml) on the survival of the cells were evaluated at 24 and 96 hrs with MTT assay. To evaluate the proliferation in long term, MC3T3-E1 cells were treated with different concentrations of B (0, 0.1, 1, 10, 100 and 1000 ng/ml) and were counted on days 2, 5, and 14. While in short term, decreased cell survival rate was observed at 1000 ng/ml and above, at long term no statistically significant difference was detected in different B concentrations applied. Slight decreases at the proliferation of the B-treated groups were determined on days 5 and 14 but one-way analysis of variance revealed that the difference was statistically insignificant. In mineralization assay, increased mineralized nodules were apparently observed in B treatment (1 and 10 ng/ml concentrations) groups. Based on quantitative RT-PCR results, remarkable regulation in favor of osteoblastic function for Collagen type I (COL I), Osteopontin (OPN), Bone Sialoprotein (BSP), Osteocalcin (OCN) and RunX2 mRNA expressions were observed in B treatment groups in comparison with untreated control groups. Increased BMP-4, -6 and -7 protein levels were detected at 0.1, 1, 10 and 100 ng/ml B concentrations. Results of the study suggest that at the molecular level B displays important roles on bone metabolism and may find novel usages at the regenerative medicine.

RAPD analysis of seized marijuana ( Cannabis sativa L. ) in Turkey

Cannabis sativa L. is a multiple-use plant. However, its cultivation is strictly controlled due to its psychoactive nature and usage in producing drugs such as marijuana, and hashish. In this study, psychoactive type Cannabis samples, which were seized from 29 different locations of Turkey, were used. Interests were to identify the genetic relatedness of the seized samples and to partition molecular variance between and within populations. Randomly Amplified Polymorphic DNAs were employed for analysis based on single plant material and bulked samples of them. Data were analysed via cluster and principal coordinate analyses (PCoA). Analysis of molecular variance (AMOVA) was performed to obtain variations between and within populations. Cannabis accessions were basically separated into two main groups by PCoA and cluster analyses according to geographical regions. One of them was made up of Cannabis plants, which were seized from mostly western part of Turkey (group 1). The other one was made up of Cannabis plants that were seized from mostly eastern part of Turkey (group 2). It is found that 20.23 percent of the genetic variation is due to differences between accessions groups while 79.77 percent of the genetic variation is due to between accessions within accessions groups. Compared to group1, group 2 showed more variation.

Investigation of matrix metalloproteinase-1--1607 1G/2G polymorphism in a Turkish population with periodontitis.

AIM: Matrix metalloproteinase-1 (MMP-1) is a proteolytic enzyme that degrades extracellular matrix and plays a fundamental role during destruction of periodontal tissues. The aim of this study was to examine the association between MMP-1 -1607 1G/2G polymorphism and chronic periodontitis susceptibility in a Turkish population. MATERIAL AND METHODS: A total of 180 subjects were enrolled in this study. All the subjects received a periodontal examination including full-mouth clinical attachment loss measurements, probing depths, plaque index scores, gingival index scores and radiographic bone loss ratios. Three groups formed according to periodontal conditions were healthy, moderate periodontitis and severe periodontitis groups. MMP-1 -1607 1G/2G gene promoter polymorphism was genotyped using a polymerase chain reaction-restriction fragment length polymorphism method. RESULTS: Analysis of the polymorphism showed no differences in distribution of the MMP-1 -1607 1G/2G polymorphism among healthy, moderate periodontitis and severe periodontitis groups (p>0.05). When the groups were further stratified by smoking status, we found no significant differences in genotype distributions, allele frequencies and carriage rates among any groups either (p>0.05). CONCLUSIONS: On the basis of the results, no significant association is found for the MMP-1 -1607 1G/2G polymorphism with susceptibility to periodontitis. Moreover, smoking status did not seem to affect this result.

Inter simple sequence repeats separate efficiently hemp from marijuana ( Cannabis sativa L. )

Cannabis sativa L. is a multiple-use plant that provides raw material for the production of seed oil, natural fiber for textiles, automotive and pulp industries. It has also been used in insulating boards, ropes, varnishes, animal feed, and as medicinal agents. Cannabis has potential to be used for phytoremediation: however, its cultivation is strictly controlled due to its psychoactive nature and usage in producing drugs such as marijuana, and hashish. In this study, psychoactive type Cannabis samples, which were seized from 23 different locations of Turkey, and nine hemp type Cannabis accessions, as well as an unknown accession were used. Our interest was to identify the genetic relatedness of the seized samples and to separate drug and hemp type plants. Inter Simple Sequence Repeats (ISSRs) were employed for analysis based on single plant material (SET1) and bulked samples of them (SET2). Data was analysed via cluster analysis and principal coordinate analysis (PCoA). PCoA analyses, by using SET1 and SET2, were able to efficiently discriminate the seized samples from the fiber type accessions. However, separation of the plants was not clear via unweighted pair-group method using arithmetic average (UPGMA) dendogram in SET1, while they were clearly separated in SET2. Hemp type accessions showed high levels of variation compared to drug type Cannabis both in SET1 and SET2.

Identification of the difference in extracellular matrix and adhesion molecules of cultured human gingival fibroblasts versus juvenile hyaline fibromatosis gingival fibroblasts using cDNA microarray analysis.

BACKGROUND: A difference from the normal range in collagen profile and perivascular hyaline deposition in the dermis and gingiva has been demonstrated histopathologically in juvenile hyaline fibromatosis (JHF), which is an autosomal recessive disease. The aim of this study was to understand the mechanism of gingival overgrowth in JHF, and to observe differences in the expression of genes regulating extracellular matrix organization. METHODS: Human gingival fibroblasts (GF) were obtained from individuals who have clinically healthy gingival tissue. JHF-GF were obtained from a patient who underwent a gingivectomy. Cultured fibroblast cells were examined visually using a phase contrast microscope. Total RNA from both cell types was isolated, and after biotin-deoxyuridine triphosphate (dUTP) labeling of cDNA, hybridization was performed with a pathway-specific gene expression profiling array membrane. Extracellular matrix (ECM) and adhesion molecule (AM) mRNA expressions in GF and JHF-GF were analyzed, and microarray data on genes modulating ECM remodeling were confirmed with reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: Cell morphology differences were observed between fibroblast types. Although type I collagen gene expression levels were almost the same, decreased type IV collagen expression was noted in JHF-GF versus GF. Decreased matrix metalloproteinase (MMP) and increased tissue inhibitor of matrix metalloproteinase (TIMP) transcripts were noted in JHF-GF versus GF. Increased fibronectin and decreased laminin mRNA expression were observed in JHF-GF when compared to GF. The present findings suggest that GF and JHF-GF differ not only morphologically but also in the expression level of ECM and AM genes involving connective tissue turnover and remodeling. CONCLUSIONS: Results from these analyses may be helpful to clarify the nature of overgrowth mechanisms, especially regarding enzymes and their inhibitors. This information is important in understanding the remodeling of ECM. The gingival overgrowth that is observed in JHF patients may be explained by a decreased level of MMPs and increased blockage of MMPs with TIMPs.