Jelena Roganović

The Levels of Vascular Endothelial Growth Factor and Bone Morphogenetic Protein 2 in Dental Pulp Tissue of Healthy and Diabetic Patients

INTRODUCTION Vascular endothelial growth factor (VEGF) and bone morphogenetic protein 2 (BMP 2) are growth factors (GFs) identified within the dentine-pulp complex and involved into the cellular events connected to the pulp-healing response. It is well established that the expression of these GFs is increased in different tissues in diabetes mellitus. Because there are no data concerning the levels of VEGF and BMP 2 in human dental pulp, the aim of present study was to quantify VEGF and BMP 2 levels in intact dental pulp and dental pulp that underwent reactive dentinogenesis in healthy and diabetic human subjects. METHODS The study was conducted on 28 healthy and 28 subjects with controlled diabetes type II who underwent pulp extirpation as a part of prosthetic rehabilitation. Pulp were collected from intact teeth and teeth treated by indirect pulp capping. The levels of VEGF and BMP 2 were determined in the pulp tissue lysates with enzyme-linked immunosorbent assay. RESULTS The levels of VEGF and BMP 2 were significantly higher in intact teeth pulp of diabetic than in healthy subjects. The concentrations of these GFs were significantly lowered in teeth with indirect pulp capping both in healthy and diabetic persons. Furthermore, VEGF and BMP 2 levels were in strong positive correlation. CONCLUSIONS Similar changes in the levels of VEGF and BMP 2 in intact and treated teeth of healthy and diabetic patients could be suggestive of associated roles of these GFs in responses of healthy and diabetic dental pulp.

The effects of anti‐hypertensives and type 2 diabetes on salivary flow and total antioxidant capacity

OBJECTIVE The present cross-sectional study aimed to determine the effect of first-line anti-hypertensive drugs (enalapril, metoprolol, and combinations of enalapril with metoprolol and/or hydrochlorothiazide) on salivary gland function and salivary total antioxidant capacity (TAC) in hypertensive patients with/without diabetes mellitus (DM) type 2. MATERIALS AND METHODS Salivary gland function was measured as xerostomia (interview) and unstimulated whole saliva flow rate (UWSFR) in 447 subjects (387 hypertensive and 60 healthy). Salivary TAC was evaluated by spectrophotometric assay. RESULTS Enalapril is not xerogenic, while metoprolol and drug combinations are. In the presence of DM type 2, all drugs, except metoprolol, had pronounced xerogenic effect. Binary logistic regression analysis found enalapril to be significantly associated with decreased risk of xerogenic effect development, while DM type 2 with increased risk. In the presence of enalapril in hypertensive patients with/without DM type 2 salivary TAC was similar to that in healthy subjects, while for metoprolol was reduced. CONCLUSIONS Enalapril is not xerogenic but is antioxidant, which moderately reduces the risk of xerogenic effect development even in the presence of DM type 2. However, metoprolol and drug combinations exhibit xerogenic effect. In DM type 2, xerogenic effect of all drugs was pronounced except of metoprolol.

Impairment of acetylcholine-mediated endothelium-dependent relaxation in isolated parotid artery of the alloxan-induced diabetic rabbit

The aim of this study was to assess the effect of type 1 diabetes mellitus (induced by a single intravenous injection of 100 mg kg(-1) of alloxan) on acetylcholine (ACh)-induced relaxation in isolated rabbit parotid gland feeding artery. Isometric force measurements and quantification of inducible nitric oxide synthase (iNOS) mRNA by real-time RT-PCR were made in parotid artery rings from diabetic and control rabbits. Acetylcholine induced concentration- and endothelium-dependent vasorelaxation that was significantly decreased in parotid artery rings from diabetic rabbits. Schild analysis of the ACh vasorelaxant effect, in the presence of selective muscarinic receptor antagonists, revealed involvement of the M(3) receptor subtype in parotid artery rings from both control and diabetic rabbits, with no change in antagonist affinity constants. The inhibitory effects of indomethacin, a non-selective inhibitor of cyclooxygenase, and of high potassium, an inhibitor of hyperpolarization, on ACh vasorelaxation were increased. The effect of N(G) -nitro-l-arginine, a non-selective inhibitor of NOS, was decreased in diabetes. S-methylisothiourea, a selective inhibitor of iNOS, significantly reduced ACh vasorelaxation only in parotid artery rings from diabetic rabbits. Also, up-regulation of iNOS mRNA expression was detected in parotid artery rings from diabetic rabbits. These results suggest that in parotid artery rings from diabetic rabbits, impaired endothelium-dependent vasorelaxation to ACh appears to be caused by the loss of a nitric oxide-mediated component and increased iNOS expression, and is unlikely to be caused by a change at the M(3) receptor level.

ACh- and VIP-induced vasorelaxation in rabbit facial artery after carotid artery occlusion

OBJECTIVES The influence of carotid artery occlusion (10, 30 and 60 min) on regulatory mechanisms implicated in the vasorelaxant responses of isolated glandular branch of rabbit facial artery to acetylcholine (ACh) and vasoactive intestinal polypeptide (VIP) was examined. DESIGN In organ bath studies with arterial rings precontracted with phenylephrine (1 microM), before and after carotid artery occlusion, changes in isometric tension were recorded. RESULTS Endothelium-dependent vasorelaxation by ACh and endothelium-independent vasorelaxation by VIP were significantly reduced, started from 30 and 10 min of carotid occlusion, respectively. Inhibitory effect of indomethacin on ACh vasorelaxation was enhanced whilst effect of N(G)-nitro-L-arginine reduced, started from 30 min of carotid occlusion. Sodium nitroprusside-induced vasorelaxation was not changed after carotid occlusion. Inhibition of VIP vasorelaxation by L-N(omega)-nitroarginine-2,4-L-diaminobutyric-amide, was reduced, started from 30 min of carotid occlusion. Forskolin enhanced VIP-induced vasorelaxation in control rings but this effect was reduced started from 30 min of occlusion. In the presence of VIP, vasorelaxant effect of ACh was increased; the increase was reduced, started from 10 min of carotid occlusion. CONCLUSIONS The present investigation provides evidence for the decreased responsiveness to both, ACh-endothelium-dependent and VIP-endothelium-independent vasorelaxation in rabbit facial artery after carotid occlusion. In addition, the data suggest that ischaemia alters contribution of endothelial nitric oxide (eNO) and prostaglandin to ACh, and vascular smooth muscles cAMP and neuronal NO to VIP vasorelaxant effects.

Effect of neuropeptide Y on norepinephrine-induced constriction in the rabbit facial artery after carotid artery occlusion.

BACKGROUND/AIM Atherosclerotic-occlusive changes could be observed in orofacial branches of the external carotid artery. Atherosclerosis-induced ischemia caused alteration in production and release of endothelial factors. The aim of this study was to investigate the influence of carotid artery occlusion (10, 30 and 60 min) on vascular effects of norepinephrine (NOR) and neuropeptide Y (NPY) in the isolated glandular branch of the rabbit facial artery, the main feeding artery for the submandibular gland. METHOD Changes in isometric tension were recorded in organ bath studies with arterial rings, before and after carotid artery occlusion. RESULTS Concentration-dependent vasocontractile effect of NOR was significantly augmented after 30 and 60 min of carotid occlusion, but only in the rings with intact endothelium. Given alone, NPY showed no effect in isolated glandular branch of the rabbit facial artery, but enhanced NOR vasoconstriction in all the investigated rings. NOR vasocontractile effect enhancement in the presence of NPY was attenuated after 30 and 60 min of carotid occlusion. Also, enhancement of NOR vasoconstriction by NPY was significantly higher in endothelium-intact rings compared to endothelium-denuded rings obtained after 30 and 60 min of carotid occlusion. CONCLUSION The present investigation provides results of increased vasocontractile effect of NOR and decreased enhancing effect of NPY on NOR vasoconstriction in the rabbit facial artery after carotid occlusion that is related to altered endothelium function.

Clinical antibacterial effectiveness and biocompatibility of gaseous ozone after incomplete caries removal

ObjectivesTo evaluate local effect of gaseous ozone on bacteria in deep carious lesions after incomplete caries removal, using chlorhexidine as control, and to investigate its effect on pulp vascular endothelial growth factor (VEGF), neuronal nitric oxide synthase (nNOS), and superoxide dismutase (SOD).Materials and methodsAntibacterial effect was evaluated in 48 teeth with diagnosed deep carious lesion. After incomplete caries removal, teeth were randomly allocated into two groups regarding the cavity disinfectant used: ozone (open system) or 2% chlorhexidine. Dentin samples were analyzed for the presence of total bacteria and Lactobacillus spp. by real-time quantitative polymerase chain reaction. For evaluation of ozone effect on dental pulp, 38 intact permanent teeth indicated for pulp removal/tooth extraction were included. After cavity preparation, teeth were randomly allocated into two groups: ozone group and control group. VEGF/nNOS level and SOD activity in dental pulp were determined by enzyme-linked immunosorbent assay and spectrophotometric method, respectively.ResultsOzone application decreased number of total bacteria (p = 0.001) and Lactobacillus spp. (p < 0.001), similarly to chlorhexidine. The VEGF (p < 0.001) and nNOS (p = 0.012) levels in dental pulp after ozone application were higher, while SOD activity was lower (p = 0.001) comparing to those in control pulp.ConclusionsAntibacterial effect of ozone on residual bacteria after incomplete caries removal was similar to that of 2% chlorhexidine. Effect of ozone on pulp VEGF, nNOS, and SOD indicated its biocompatibility.Clinical relevanceOzone appears as effective and biocompatible cavity disinfectant in treatment of deep carious lesions by incomplete caries removal technique.

The effect of piezosurgery on the oxidative stress and immediate post extraction discomfort following complex teeth extractions prior to implant placement

1 ITI Scholar, Department for Craniofacial Science, University of Connecticut, United States ; 2 Department for Reconstructive Science, University of Connecticut, United States ; 3 Department for Oral Surgery, University of Belgrade, Serbia ; 4 Department of Pharmacology in Dentistry, School of Dental Medicine, University of Belgrade, Serbia ; 5 Department of Oral Surgery, School of Dental Medicine, University of Belgrade, Serbia