Introduction: Vascular endothelial growth factor (VEGF) is one such candidate. It functions as an endothelial cell mitogen, chemotactic agent, and inducer of vascular permeability. Other angiogenic growth factors such as basic fibroblast growth factor (bFGF) and transforming growth factor β (TGF-β) have been described, but VEGF is unique for its effects on multiple components of the wound healing cascade, including angiogenesis and recently shown epithelization and collagen deposition. VEGF is produced by many cell types that participate in wound healing: endothelial cells, fibroblasts, smooth muscle cells, platelets, neutrophils, and macrophages. . Objectives: To evaluate the expression of VEGF during healing of extracted sockets in diabetic rats. Materials and methods: 24 adult male rats aged about 6 months and weighing about 250 gms were divided into 2 groups; Group I (12 rats) non diabetic and Group II (12 rats) diabetic. For study group, the rats were fasted overnight and diabetes was induced by a single intra peritoneal injection of streptozotocin 60 mg/kg body weight in 0.1 M citrate buffer. All animals, were exposed to surgical wounds (extracted lower right first molar). They were sacrificed as follows 4 rats from each group at intervals of 3 days, 7 days, 21 days after extraction for immunohistochemical study.Results: In the present study, immunohistochemical expression of VEGF was detected as brown cytoplasmic reaction. All the examined cases showed positive results for VEGF with different scores. Conclusions: these results demonstrated the expression of VEGF in diabetic rats during healing of extraction sockets significantly higher than control group in late periods.

BACKGROUND:Monosodium glutamate is one of the most frequently applied taste enhancers in modern food industry. Long term consumption of high doses of MSG can elevate the oxidative stress mainly through the production of Reactive Oxygen Species and lead to cytotoxicity in multiple tissues in the body. Vitamin C is a well-known potent antioxidant and has been shown to protect various tissues against oxidative stress induced damage. OBJECTIVE: to determine the histological effect of Monosodium glutamate and vitamin C on parotid glands of albino rats. MATERIALS AND METHODS: 30 male adult albino rats were equally divided into 3 groups; control group that received 1 ml distilled water orally once daily, MSG group that received 30 mg/kg bodyweight of Monosodium Glutamate daily and MSG+ Vit C group that received 30 mg/kg bodyweight of MSG followed by 100mg/kg bodyweight of Vitamin C in distilled water daily by oral gavage. After 8 weeks, rats were euthanized, parotid glands were dissected out to be processed for histological examination. RESULTS: Histological examination of parotid of MSG group revealed acinar cells with signs of atrophy and degeneration demonstrated as cytoplasmic vacuolations, pyknotic or apoptotic nuclei. Secretory striated duct showed luminal dilatation and partial loss of basal striations. MSG+ Vit C group showed more preservation of normal architecture of serous acini and ducts. CONCLUSION: MSG produced significant degenerative effects on parotid glands of albino rats and coadministration of vitamin C was effective in protecting gland tissue against MSG-induced damage.

Introduction: Periodontitis is the 6th classic complication of Diabetes Mellitus (DM). Both Diabetes & periodontitis are chronic inflammatory diseases. As DM accelerates bone resorption; when periodontal disease affects a diabetic individual, extensive alveolar bone loss occurs. Propolis is a natural antibiotic & anti-inflammatory agent that honey bees (Apis mellifera) collect from tree buds or other botanical sources; and use in the construction as well as the protection of their hives. Due to its broad pharmacological potential, propolis has been employed extensively in medicine, since ancient times. Objective: Was to evaluate the effect of systemic administration of propolis on the alveolar bone loss, induced by periodontitis, in diabetic rats. Materials and methods: Twenty-four Albino rats were divided into three equal groups: group (1) normal control (NC), group (2) Diabetes + Periodontitis (DP) and group (3) Diabetes + Periodontitis + Propolis (DP-Pro). DM type 1was induced in rats of groups (2) and (3), by single intraperitoneal injection of Streptozotocin. Then, periodontitis was induced by ligature placement sub marginally around the right mandibular 1st molar. In group (3), propolis was administrated systemically by gastric feeding 400mg/Kg/day for 8weeks. At the end of this period, animals were sacrificed and dissected. The alveolar bone surface integrity interproximally was evaluated by scanning electron microscopy (SEM), and results were compared between groups. Results: After 2 months, group (2) showed more alveolar bone loss compared to the 2 other groups. Groups (1) & (3) showed an intact, smooth & regular bone surface, while group (2) specimens showed an irregular & porous bone surface with extensive resorption. Conclusion: This study showed that the systemic administration of propolis effectively prevented the extensive alveolar bone loss associated with experimental periodontitis in diabetic rat models. Thus, propolis might be used as an adjunctive treatment for periodontitis associated with Diabetes.

Objective: To investigate the time course of osteocyte apoptosis in a rat model of orthodontic tooth movement as revealed by the caspase-3 activation pathway. Materials and Methods: Fifteen male Sprague Dawley rats (6-9weeks old) were loaded with an orthodontic appliance. A spring delivering 10-12 g of force was placed between the maxillary first molar and the incisor to displace the first molar mesially. The animals were equally divided into three time points: 24 hours, 3 and 7 days of orthodontic loading. Five animals served as 0 day group. Caspase 3 immunostaining, was performed on histologic sections of the first molars. The labeling was quantified in osteocytes on the mesial and distal sides of the alveolar bone in each group. Results: Caspase 3 labeling at the mesial side significantly increased at 1, 3 and 7 days after orthodontic loading compared to the control group. No peak increase was observed. There was no significant difference in caspase 3 labeling at the distal side. Conclusions: Osteocyte apoptosis during orthodontic tooth movement could be revealed by caspase 3 immunostaining. This suggest that caspase 3 apoptotic pathway is involved in osteocyte death during orthodontic tooth movement.