S. Jepsen

The Large Non-coding RNA ANRIL, which is Associated with Atherosclerosis, Periodontitis, and Several Forms of Cancer, regulates ADIPOR1, VAMP3, and C11ORF10

The long non-coding RNA ANRIL is the best replicated genetic risk locus of coronary artery disease (CAD) and periodontitis (PD), and is independently associated with a variety of other immune-mediated and metabolic disorders and several forms of cancer. Recent studies showed a correlation of decreased concentrations of proximal ANRIL transcripts with homozygous carriership of the CAD and PD main risk alleles. To elucidate the relation of these transcripts to disease manifestation, we constructed a short hairpin RNA in a stable inducible knock-down system of T-Rex 293 HEK cell lines, specifically targeting the proximal transcripts EU741058 and DQ485454. By genome-wide expression profiling using Affymetrix HG1.0 ST Arrays, we identified the transcription of ADIPOR1, VAMP3 and C11ORF10 to be correlated with decreased ANRIL expression in a time-dependent manner. We validated these findings on a transcriptional and translational level in different cell types. Exploration of the identified genes for the presence of disease associated variants, using Affymetrix 500K genotyping and Illumina custom genotyping arrays, highlighted a region upstream of VAMP3 within CAMTA1 to be associated with increased risk of CAD [rs10864294 P = 0.015, odds ratio (OR) = 1.30, 95% confidence interval (CI) = 1.1-1.6, 1471 cases, 2737 controls] and aggressive PD (AgP; P = 0.008, OR = 1.31, 95% CI = 1.1-1.6, 864 cases, 3664 controls). In silico replication in a meta-analysis of 14 genome-wide association studies of CAD of the CARDIoGRAM Consortium identified rs2301462, located on the same haplotype block, as associated with P = 0.001 upon adjustment for sex and age. Our results give evidence that specific isoforms of ANRIL regulate key genes of glucose and fatty acid metabolism.

Molecular identification and quantification of bacteria from endodontic infections using real-time polymerase chain reaction

INTRODUCTION It was the aim of the present study to evaluate root canal samples for the presence and numbers of specific species as well as for total bacterial load in teeth with chronic apical periodontitis using quantitative real-time polymerase chain reaction (PCR). METHODS Forty adult patients with one radiographically documented periapical lesion were included. Twenty teeth presented with primary infections and 20 with secondary infections, requiring retreatment. After removal of necrotic pulp tissue or root canal filling, a first bacterial sample was obtained. Following chemo-mechanical root canal preparation a second sample was taken and a third sample was obtained after 14 days of intracanal dressing with calcium hydroxide. Analysis by real-time PCR enabled the quantification of total bacterial counts and of nine selected species. RESULTS Root canals with primary infections harbored significantly more bacteria (by total bacterial count) than teeth with secondary infections (P < 0.05). Mean total bacterial count in the retreatment group was 2.1 x 10(6) and was significantly reduced following root canal preparation (3.6 x 10(4)) and intracanal dressing (1.4 x 10(5)). Corresponding values for primary infections were: 4.6 x 10(7), 3.6 x 10(4), and 6.9 x 10(4). The numbers of the selected bacteria and their detection frequency were also significantly reduced. CONCLUSION Root canals with primary infections contained a higher bacterial load. Chemo-mechanical root canal preparation reduced bacterial counts by at least 95%.

Human β-defensins differently affect proliferation, differentiation, and mineralization of osteoblast-like MG63 cells.

Purpose of this study was to investigate whether human β‐defensins (hBDs) affect maturation and proliferation of osteoblast‐like MG63 cells in vitro. Osteoblast‐like MG63 cells were stimulated with hBD‐1, ‐2, and ‐3 under control conditions and with hBD‐2 during experimental inflammation (induced by interleukin‐1β, tumor necrosis factor‐α, toll‐like receptor‐2 and ‐4 agonists). Expression of different osteogenic markers and hBDs were analyzed by real‐time PCR, immunohistochemistry, and enzyme‐linked immunosorbent assay. In addition, alkaline phosphatase (ALP) enzyme activity and biomineralization as markers for differentiation were monitored. All tested hBDs were expressed on mRNA and protein level in MG63 cells. Only stimulation with hBD‐2 elevated the proliferation rate. hBD‐2 and hBD‐3 positively affected the differentiation of osteoblast‐like cells provided by increased transcript levels of osteogenic markers, up‐regulated ALP enzyme activity and enhanced mineralized nodule formation. All pro‐inflammatory stimuli enhanced interleukin‐6 and hBD‐2 expression and down‐regulated markers of osteoblastic differentiation. In accordance, inflammation increased transcript level of Notch‐1 (an inhibitor of osteoblastic differentiation). hBD‐2 was not able to revert effects of inflammation on differentiation. In bone cells human β‐defensins exhibit further functions than antimicrobial peptide activity. These include stimulation of proliferation and differentiation. Differentiation arrest due to inflammation could not be overcome by hBD‐2 alone. J. Cell. Physiol. 227: 994–1003, 2012.

Human Beta-Defensin-1, -2, and -3 Exhibit Opposite Effects on Oral Squamous Cell Carcinoma Cell Proliferation

The objective of this study was to investigate the impact of human beta-defensins (hBDs) on oral squamous cell carcinoma (OSCC) proliferation and hBD expression in vitro. BHY-OSCC cell lines were stimulated with hBD-1, -2, and -3. Proliferation of BHY cells was ascertained and hBD-mRNA expression was evaluated by real-time PCR. Proliferation of BHY cells decreased by 25% in response to hBD-1 stimulation but increased after stimulation with hBD-2 and -3. HBD-1 stimulation enhanced hBD-3 expression, whereas HBD-2 stimulation decreased early hBD-3 expression. HBD-3 stimulation enhanced hBD-1 expression. HBDs profoundly impact on OSCC proliferation and hBD expression in vitro. Therefore, hBD-1 might function as a tumor suppressor gene in OSCCs, while hBD-2 and -3 might be protooncogenes.

Decreased gene expression of human β-defensin-1 in the development of squamous cell carcinoma of the oral cavity

The aim of this study was to investigate the gene expression of human beta-defensin-1, -2, -3 (hBD-1, -2, -3), interleukin-1beta, tumour necrosis factor-alpha and cyclooxygenase-2 in oral squamous cell carcinoma (OSCC) compared to benign and premalignant lesions as well as healthy controls. Biopsies of healthy gingiva (n=5), irritation fibroma (n=5), leukoplakia (n=5) and OSCC (n=5) were obtained during routine surgical procedures. RNA was extracted according to standard protocols and transcripts of hBD-1, -2, -3, interleukin-1beta, tumour necrosis factor-alpha and cyclooxygenase-2 were analysed by real-time polymerase chain reaction. The expression of hBD-1 was reduced in all lesions (5-fold in irritation fibroma and 2.5-fold in leukoplakia), but most significantly (50-fold) in OSCC. hBD-1 appears to play a role in the development of OSCC. The loss of its function might contribute to the malignant progression of these tumours.

Nuclear hBD-1 accumulation in malignant salivary gland tumours

BackgroundWhereas the antimicrobial peptides hBD-2 and -3 are related to inflammation, the constitutively expressed hBD-1 might function as 8p tumour suppressor gene and thus play a key role in control of transcription and induction of apoptosis in malignant epithelial tumours. Therefore this study was conducted to characterise proteins involved in cell cycle control and host defence in different benign and malignant salivary gland tumours in comparison with healthy salivary gland tissue.Methods21 paraffin-embedded tissue samples of benign (n = 7), and malignant (n = 7) salivary gland tumours as well as healthy (n = 7) salivary glands were examined immunohistochemically for the expression of p53, bcl-2, and hBD-1, -2, -3.ResultsHBD-1 was distributed in the cytoplasm of healthy salivary glands and benign salivary gland tumours but seems to migrate into the nucleus of malignant salivary gland tumours. Pleomorphic adenomas showed cytoplasmic as well as weak nuclear hBD-1 staining.ConclusionHBD-1, 2 and 3 are traceable in healthy salivary gland tissue as well as in benign and malignant salivary gland tumours. As hBD-1 is shifted from the cytoplasm to the nucleus in malignant salivary gland tumours, we hypothesize that it might play a role in the oncogenesis of these tumours. In pleomorphic adenomas hBD-1 might be connected to their biologic behaviour of recurrence and malignant transformation.

Human periodontal ligament cells facilitate leukocyte recruitment and are influenced in their immunomodulatory function by Th17 cytokine release.

The objective of this in vitro study was to examine the immunomodulatory impact of human periodontal ligament (PDL) cells on the nature and magnitude of the leukocyte infiltrate in periodontal inflammation, particularly with regard to Th17 cells. PDL cells were challenged with pro-inflammatory cytokines (IL-1ß, IL-17A, and IFN-γ) and analyzed for the expression of cytokines involved in periodontal immunoinflammatory processes (IL-6, MIP-3 alpha, IL-23A, TGFß1, IDO, and CD274). In order to further investigate a direct involvement of PDL cells in leukocyte function, co-culture experiments were conducted. The expression of the immunomodulatory cytokines studied was significantly increased under pro-inflammatory conditions in PDL cells. Although PDL cells did not stimulate leukocyte proliferation or Th17 differentiation, these cells induced the recruitment of leukocytes. The results of our study suggest that PDL cells might be involved in chronic inflammatory mechanisms in periodontal tissues and thus in the transition to an adaptive immune response in periodontitis.

Gene expression of oncogenes, antimicrobial peptides, and cytokines in the development of oral leukoplakia.

OBJECTIVE The aim of this study was to investigate the expression pattern of oncogenes, antimicrobial peptides, and genes involved in inflammation in leukoplakia of the oral cavity compared with healthy gingiva. STUDY DESIGN Biopsies of healthy gingiva (n=20) and leukoplakia (n=20), were obtained during routine surgical procedures. RNA was extracted according to standard protocols. Transcript levels of alpha-defensin (DEFA) 1/3, DEFA-4, S100-A7, deleted-in-oral-cancer (Doc) 1, interleukin (IL) 1beta, IL-6, IL-8, IL-10, tumor necrosis factor (TNF) alpha, cyclooxygenase (Cox) 2, epidermal growth factor (EGF), keratinocyte growth factor (KGF), transforming growth factor (TGF) beta1, TGF-alpha, collagen-IA1 (Col-1), and tenascin-c were analyzed by real-time reverse-transcription polymerase chain reaction. The proteins encoded by the different genes were visualized by immunostaining. RESULTS Compared with healthy gingiva (set as 1), there was an increased gene expression of DEFA-4 (179.2-fold), S100-A7 (25.4-fold), EGF (24.8-fold), TGF-beta1 (25.2-fold), and tenascin-c (34.3-fold) in oral leukoplakia. The expression of IL-1beta and Doc-1 was decreased (0.01-fold and 0.2-fold, respectively). CONCLUSIONS The combination of an increased expression of the antimicrobial peptide DEFA-4, the oncogene S100-A7, EGF, and tenascin-c, and a decreased Doc-1 expression in oral leukoplakia might characterize its potency of malignant transformation. Chronic inflammation seems not to be involved in the development of this lesion.

Interactions of regenerative, inflammatory and biomechanical signals on bone morphogenetic protein‐2 in periodontal ligament cells

BACKGROUND AND OBJECTIVE Regeneration of periodontal tissues by EMD remains a major challenge because a number of modifying factors are as yet unknown. The effects of EMD seem to be mediated, at least in part, by bone morphogenetic protein-2 (BMP-2). This in vitro study was performed to examine whether the effects of EMD on BMP-2 activity are modulated by inflammatory and/or biomechanical signals. MATERIAL AND METHODS   Periodontal ligament cells were seeded on BioFlex(®) plates and exposed to EMD under normal, inflammatory or biomechanical loading conditions for 1 and 6 d. In order to mimic proinflammatory or biomechanical loading conditions in vitro, cells were stimulated with interleukin-1β (IL-1β), which is increased at inflamed periodontal sites, and cyclic tensile strain of various magnitudes, respectively. The synthesis of BMP-2, its receptors (BMPR-1A, BMPR-1B and BMPR-2) and its inhibitors (follistatin, matrix gla protein and noggin) were analyzed using real-time RT-PCR and ELISA. RESULTS In EMD-treated cells, BMP-2 synthesis was increased significantly at 1 d. EMD also induced the expression of all BMP receptors, and of the BMP inhibitors follistatin and noggin. In general, IL-1β and biomechanical loading neither down-regulated BMP-2 nor up-regulated BMP inhibitors in EMD-stimulated cells. However, IL-1β and biomechanical loading, when applied for a longer time period, caused a down-regulation of EMD-induced BMP receptors. CONCLUSION EMD induces not only BMP-2, but also its receptors and inhibitors, in PDL cells. IL-1β and biomechanical forces may counteract the beneficial effects of EMD on BMP-2 activity via the down-regulation of BMP receptors.

Beneficial Effects of Adiponectin on Periodontal Ligament Cells under Normal and Regenerative Conditions

Type 2 diabetes and obesity are increasing worldwide and linked to periodontitis, a chronic disease which is characterized by the irreversible destruction of the tooth-supporting tissues, that is, periodontium. The mechanisms underlying the association of diabetes mellitus and obesity with periodontal destruction and compromised periodontal healing are not well understood, but decreased plasma levels of adiponectin, as found in diabetic and obese individuals, might be a critical mechanistic link. The aim of this in vitro study was to examine the effects of adiponectin on periodontal ligament (PDL) cells under normal and regenerative conditions, and to study the regulation of adiponectin and its receptors in these cells. Adiponectin stimulated significantly the expression of growth factors and extracellular matrix, proliferation, and in vitro wound healing, reduced significantly the constitutive tumor necrosis factor-α expression, and caused a significant upregulation of its own expression. The beneficial actions of enamel matrix derivative on a number of PDL cell functions critical for periodontal regeneration were partially enhanced by adiponectin. The periodontopathogen Porphyromonas gingivalis inhibited the adiponectin expression and stimulated the expression of its receptors. In conclusion, reduced levels of adiponectin, as found in type 2 diabetes and obesity, may compromise periodontal health and healing.