Oral and Maxillo-Facial Manifestations of Systemic Diseases: An Overview

Many systemic (infective, genetic, autoimmune, neoplastic) diseases may involve the oral cavity and, more generally, the soft and hard tissues of the head and neck as primary or secondary localization. Primary onset in the oral cavity of both pediatric and adult diseases usually represents a true challenge for clinicians; their precocious detection is often difficult and requires a wide knowledge but surely results in the early diagnosis and therapy onset with an overall better prognosis and clinical outcomes. In the current paper, as for the topic of the current Special Issue, the authors present an overview on the most frequent clinical manifestations at the oral and maxillo-facial district of systemic disease.

Osteoblast apoptosis in periodontal disease: role of TNF-related apoptosis-inducing ligand

Periodontal disease (Pd) is characterized by an increased osteoclast resorption and a decreased osteoblast (OB) bone formation. OBs obtained from alveolar bone of Periodontitis patients (Pp) undergo apoptosis in the presence of TNF-related apoptosis-inducing ligand (TRAIL). We studied the intracellular apoptotic pathway induced by TRAIL; TRAIL death (DR4, DR5) and decoy (DcR1, DcR2) receptors expression in Periodontitis patients OBs (PpOBs), and we measured the concentration of TRAIL in the serum of Pp. We demonstrated that DNA fragmentation and activation of caspase-8 and caspase-3 in PpOBs, following TRAIL stimulation, occurred in shorter time; moreover, a higher amount of both caspases was activated in order to direct OBs. Down-regulation of DcR2 in PpOBs was demonstrated and high TRAIL levels were detected in the serum of Pp. In conclusion, our data suggest that PpOBs are more sensitive to TRAIL-induced apoptosis when compared to the control group. The down-regulation of DcR2 possibly leads to an imbalanced ratio between death and decoy receptors. Our findings highlight a role of TRAIL in the pathogenesis of Pd.

Effects of Rich-in-Fat Diets and Highly Selective COX-2 Inhibitors on 7,12-Dimethylbenz-(A)-Anthracene-Induced Tumor Growth

The effects of diet, of non-steroidal anti-inflammatory drugs, or of their combination on carcinogenesis continue to be a case for controversy. Diets that are high in fat have been linked to increased risk of various tumors. At the same time there is substantial, but not conclusive, evidence that the risk of breast and colon cancer correlates with total fat intake rather than a specific type of fat. On the other hand, non-steroidal anti-inflammatory drugs (NSAIDs) have been studied extensively because they appear to delay or inhibit the development of malignant and pre-malignant lesions. 7,12-Dimethylbenz-(a)-anthracene (DMBA) has been used for a long time to induce carcinogenesis in a number of rat animal models. The present study attempts to identify the effects on DMBA-induced tumor growth (a) of diets rich in fat and (b) of the highly selective COX-2 inhibitor Celecoxib, which has been claimed to offer substantial protection against carcinogenesis.

Morphostructural analysis of human follicular stem cells on highly porous bone hydroxyapatite scaffold

In this study we investigated the in vitro behaviour, morphostructure and extracellular matrix synthesis of human dental follicular stem cells (hDFSCs) isolated from human dental bud, which resulted to be positive for mesenchymal markers (CD29, CD90, CD146 and CD166) by FACS analysis. Cells were analysed by light and electronic microscopy to evaluate their biological response either at week 1, that is before differentiation, or at weeks 3-6, when they had been cultured in osteogenic medium onto a highly porous natural scaffold material (Bio-Oss). Microscopy analysis of primary culture cells showed they had a mesenchymal stem cell-like morphostructure, spindle shaped, similar to the culture of mesenchymal stem cells derived from adult bone marrow. Also, after osteogenic differentiation, these analyses indicate typical osteoblast morphostructure and reveale a tri-dimensional organization of the cells and deposition of extracellular matrix (ECM) in close contact with biomaterial. This approach would allow to personalize the scaffold for bone tissue engineering in order to accelerate the process of osteogenesis.

The Effect of Porcine Orexin a on C-Peptide Plasma Concentrations in Pigs

The hypothalamus and the neuropeptides that are produced and act within its neuronal circuits constitute an area of extensive laboratory research. In 1998, the neuropeptide, Orexin A, was discovered and isolated from the hypothalamus of the rat. An i.c.v. injection of Orexin A into the lateral ventricle of the rat's brain causes an increase in the consumption of food, and, apart from appetite, it also seems to be regulating many other normal functions of the organism, whose regulatory and metabolic mechanisms remain unknown to date. The neuropeptide is produced by a small cluster located in and round the lateral hypothalamic area. It has been known for decades that this area is involved in the regulation of feeding and energy homeostasis in mammals. The intravenous, subcutaneous, or i.c.v. injection of Orexin A causes changes in insulin and glucagon concentrations. The same effect is also seen under in vitro experimental conditions. In this study, we investigated the potential effects of i.c.v. administration of porcine Orexin A on c-peptide concentrations in the peripheral blood of pigs, and tested whether these changes are associated with the potential effect of the neuropeptide on the function of the pancreas.

Expression and secretion of CXCL8 (IL-8), release of tryptase and transcription of histidine decarboxylase mRNA by anti-IgE-activated human umbilical cord blood-derived cultured mast cells

Activation of cytokine receptors and alterations in cytokines are thought to play important roles in neuronal dysfunction and in the pathogenesis of the nervous system diseases. CXCL8 (IL-8) is a CXC chemokine with chemotactic and inflammatory properties. Chemokines control mast cell infiltration in several inflammatory diseases, including stress and neurological dysfunctions. Using isolated human umbilical cord blood-derived cultured mast cells (HUCMC) from hematopoietic stem cells CD34+, mast cells were immunologically activated with anti-IgE at concentrations of 1, 5, 10 and 20 microg/ml leading to the dose-dependent production of IL-8 (p < 0.05). The increase in IL-8 mRNA expression was also noted when the cells were treated with anti-IgE at 10 microg/ml for 6 h. Immunologically activated HUCMC provoked the generation of tryptase in a dose- and time-dependent manner. We also found increased histidine decarboxylase (HDC) expression in activated HUCMC after 6 h of incubation, a rate-limiting enzyme responsible for the generation of histamine from histidine. Taken together, these results confirm that anti-IgE-activated mast cells release inflammatory mediators including CXCL8, a CXC chemokine which regulates several biological effects of mast cells, e.g. chemoattraction, and possibly causes cell arrest.