Blood Oxidative Stress Modulates Alveolar Bone Loss in Chronically Stressed Rats.

We aimed to investigate the effects of chronic stress (CS) on experimental periodontitis (EP) in rats. For this, 28 Wistar rats were divided into four groups: control, ligature-induced experimental periodontitis (EP), chronic stress (CS; by physical restraint model) and CS+EP (association of chronic stress and ligature-induced periodontitis). The experimental period lasted 30 days, including exposure to CS every day and ligature was performed on the 15th experimental day. After 30 days, the animals were submitted to the behavioral test of the elevated plus maze (EPM). Next, rats were euthanized for blood and mandible collection in order to evaluate the oxidative biochemistry (by nitric oxide (NO), reduced-glutathione activity (GSH), and thiobarbituric acid reactive substance levels (TBARS)) and alveolar bone characterization (by morphometric, micro-CT, and immunohistochemistry), respectively. The behavioral parameters evaluated in EPM indicated higher anxiogenic activity in the CS and CS+EP, groups, which is a behavioral reflex of CS. The results showed that CS was able to change the blood oxidative biochemistry in CS and CS+EP groups, decrease GSH activity in the blood, and increase the NO and TBARS concentrations. Thus, CS induces oxidative blood imbalance, which can potentialize or generate morphological, structural, and metabolic damages to the alveolar bone.

Curcuma longa extract protects against 5-fluorouracil-induced oral mucositis in hamsters

Abstract Curcumin, contained at Turmeric (Curcumalonga), can exert many beneficial pleiotropic activities in the gastrointestinal tract. This study evaluated the antioxidant and anti-inflammatory activity of C. longa on 5-fluorouracil (5-FU)-induced oral mucositis (OM) in hamsters. Phytochemical analysis of crude C. longa extract (CLE) was performed to detect the presence of curcumin by TLC and HPLC. Golden Syrian hamsters were orally pre-treated with CLE (5, 50, or 100mg/kg). Cheek pouch samples were subjected to macroscopic and histopathological evaluation. ELISA was performed to quantify the inflammatory cytokines IL-1ß and TNF-α. Superoxide dismutase (SOD), glutathione (GSH) and malondialdehyde (MDA) levels were assessed by ultraviolet-visible spectroscopy analysis. Behavior analysis was conducted by the open field test. Curcumin content in the CLE was 0.55%m/m ± 0.0161 (2.84%). The group treated with 5mg/kg CLE showed healing evidence with macroscopic absence of ulceration (p<0.05) and microscopic aspect of re-epithelialization, discrete inflammatory infiltrate and absence of edema. Treatment with 5mg/kg CLE significantly increased GSH levels, and reduced MDA levels and SOD activity (p˂0.05), and decreased IL-1ß (p˂0.05) and TNF-α (p˂0.01) levels. A significant reduction in walking distance, ambulation, speed, and rearing was observed for motor activity. Curcumin reduced oxidative stress, inflammation, and motor activity in hamsters with 5-FU-induced OM.