Oxidative stress and enzymatic antioxidant status in patients with nonalcoholic steatohepatitis

Oxidative stress is an important pathophysiological mechanism in nonalcoholic steatohepatitis (NASH). To assess whether there are relationships between oxidative stress and antioxidant enzymes in the development of NASH, we investigated oxidative stress by measuring serum malondialdehyde (MDA) and nitric oxide (NO) and antioxidant status by measuring serum glutathione (GSH), glutathione peroxidase (GSH-Px), glutathione reductase (GR), and superoxide dismutase (SOD). The study included 18 patients (13 men, 5 women; mean age 42 yr) with biopsy proven NASH and 16 healthy volunteers (10 men, 6 women; mean age 38 yr). Serum levels of MDA, NO, GSH, GSH-Px, GR and SOD were determined by spectrophotometric methods. Serum levels (mean +/- SD) of MDA (6.7 +/- 1.6 vs 2.8 +/- 1.7 nmol/ml, p 0.0001), NO (135 +/- 28 vs 113 +/- 35 mmol/L, p 0.04), GSH (919 +/- 137 vs 770 +/- 128 mmol/L, p 0.003) were increased in patients with NASH vs controls. Serum levels of GSH-Px (1063 +/- 152 vs 1000 +/- 94 U/L) and GR (47 +/- 22 vs 40 +/- 21 U/L) were not singnificantly different in the patients vs controls. However, the serum level of SOD (1.24 +/- 0.32 vs 1.51 +/- 0.37 U/ml, p: 0.04) was significantly decreased. Impaired antioxidant defense mechanisms may be an important factor in the pathogenesis of NASH. Treatment approaches that affect the antioxidant enzymes may be beneficial in patients with NASH.     

Stafne bone defect in the anterior mandible

Lingual mandibular bone defect, also known as Stafne bone cavity, is mostly seen in the posterior portion of the mandible. Cavities in the anterior region are very unusual, with around 50 cases reported in the English literature. They are often asymptomatic and found during routine radiographic examinations. This article describes a case of anterior Stafne bone cavity in a 56-year-old male patient.     

Comparison between tensile characteristics of various suture materials with two suture techniques: an in vitro study

Clinical Oral Investigations - The first objective of the present study was to evaluate the tensile strength and elongation to failure of commonly used suture materials in oral surgery. As a...     

Serum Lipoprotein(a) Level and its Clinical Significance in Patients with Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is a classic autoimmune disease characterised by the production of autoreactive T cells and autoantibodies that may affect every organ system. It has long been established that there is a close association between cholesterol- rich lipoproteins (such as low-density lipoprotein-cholesterol) and cardiovascular disease in patients with SLE. In this study, we evaluated total cholesterol, triglycerides, HDL-cholesterol, LDL-cholesterol, VLD-cholesterol, apolipoprotein A-1, apolipoprotein B, and cholesterol-rich serum lipoprotein(a) [Lp(a)], which is accepted to be an independent risk factor for cardiovascular disease and for atherosclerosis, in 24 patients (mean age +/- SD 31.4 +/- 9.7 years, range 16-47, 22 F) with active SLE. Twenty-six healthy age- and sex-matched (mean age +/- SD 29.7 +/- 11.3 years, range 18-49 years, 22 F) subjects were included as a control group. In patients with SLE Lp(a) levels, total cholesterol, triglycerides and VLDL-cholesterol were found to be higher and HDL-cholesterol, apolipoprotein A-1 to be lower than those of controls. In conclusion, because serum Lp(a) levels are significantly higher (P<0.01) in patients with SLE, these patients have a risk of developing cardiovascular disease and atherosclerosis. Patients with SLE should be followed up with this in mind.     

Levels of soluble E-selectin in patients with active Behçet’s disease

Behçets disease is a systemic vasculitis of unknown aetiology. Endothelial cell injury plays an important role in the pathogenesis and immunopathology of Behçets disease. E-selectin is expressed by activated endothelial cells. Because the selectin adhesion molecules are shed from activated cells, soluble forms of these proteins can be used as activation markers of endothelium (E-selectin). The pathogenesis of Behçets disease (BD) is closely related to endothelial cells, leucocyte functions and immunity. The aim of this study was to investigate circulating E-selectin adhesion molecules, which are known to play a significant part in the immune response especially by regulating interaction of the leucocytes with endothelium in BD. Plasma E-selectin concentrations were evaluated in 23 patients with BD and 20 healthy control subjects. The disease activity was evaluated by clinical manifestations (oral aphthous ulcer, genital ulceration, positive pathergy test, skin lesions, eye involvement, thrombophlebitis and arthritis) and by laboratory investigations [erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP)]. The patients were newly or previously diagnosed cases not taking any drug for BD. Levels of E-selectin were measured with commercially available sandwich enzyme-linked immunosorbent assay (ELISA) kits using human sE-selectin (cat. no: BMS 205). Plasma E-selectin concentrations of patients and controls were compared with the Mann-Whitney U test. Statistical significance was assigned to p values lower than 0.05. Serum levels (mean±SD) of soluble E-selectin (sE-selectin) were significantly higher in 23 patients with BD than in 20 healthy controls (53.2±18.2 ng/ml vs 33.8±7.5 ng/ml, p<0.0001). A statistically significant positive correlation was observed between sE-selectin levels and CRP and ESR in patients with BD (r=0.78, p<0.001 and r=0.56, p<0.01, respectively). Increases in the E-selectin in BD may be a direct consequence of the leucocyte and endothelium activations observed during the disease process. The noninvasive investigations can be used as biochemical markers for inflammation. This may provide additional information regarding disease activity along with the traditional indices such as ESR and CRP.     

Effectiveness of Palosuran in Bleomycin-Induced Experimental Scleroderma

Systemic sclerosis (SSc) is a disease characterized by skin and internal organ involvement. There is progressive accumulation of extracellular matrix components in the skin and involved organs. Tissue fibrosis is the prominent reason for mortality, and still, there is no satisfactory treatment. The aim of this study was to evaluate the effects of urotensin-II (U-II) antagonist palosuran in an animal model of scleroderma. We also planned to measure U-II, endothelin-1 (ET-1), and transforming growth factor-β1 (TGF-β1) levels, as well as the association of these levels with dermal thickness. Twenty-four male mice were included in this study and they were divided into three groups—group 1: control group, group 2: fibrosis group, and group 3: fibrosis + palosuran treatment group. Fibrosis + palosuran treatment in group 3 reduced ET-1, U-II, and TGF-β1 levels. In total, the diminished values were statistically significant in the ET-1 and TGF-β1 levels (p?<?0.05). Dermal thickness was higher in the fibrosis group, when compared with the other groups. There was no significant relationship between dermal thickness and ET-1, U-II, or TGF-β1 levels (p?>?0.05). It is believed that U-II is an important mediator in SSc, and its antagonism with palosuran could be a new treatment choice in SSc.     

Urotensin Inhibition with Palosuran Could Be a Promising Alternative in Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is a progressive and a life-threatening disease with its high morbidity and mortality ratios. On searching for new shining targets in pathogenesis, we noticed, in our previous studies, urotensin-II (UII) in systemic sclerosis with potent angiogenic and pro-fibrotic features. Owing to the mimicking properties of UII with endothelin-1 (ET1), we attempted to investigate the effect of palosuran in a PAH rat model. Thirty rats were randomly divided into three groups, with each group comprising 10 rats: group 1 (control group) received the vehicle subcutaneously, instead of monocrotaline (MCT) and vehicle; group 2 (MCT group) received subcutaneous MCT and vehicle; and group 3 (MCT + palosuran group) received subcutaneous MCT and palosuran. Serum UII, ET1, transforming growth factor-β1 (TGF-β1) levels, pulmonary arteriolar pathology of different diameter vessels, and cardiac indices were evaluated. The ET1, TGF-β1, and UII levels were significantly diminished in the treatment group, similar to the controls (p?<?0.001). Right ventricular hypertrophy index and mean pulmonary arterial pressure scores were also significantly reduced in the treatment group (p?=?0.001). Finally, in the 50–125-μm diameter arterioles, in contrast to Groups 3 and 1, there was a statistically significant thickness (p?<?0.01) in the arteriolar walls of rats in Group 2. The treatment effect on arteries of more than 125-μm diameters was found to be valuable but not significant. Owing to its healing effect on hemodynamic, histological, and biochemical parameters of MCT-induced PAH, palosuran as an antagonist of UII might be an optional treatment alternative for PAH.     

The effect of melatonin on peripheral blood cells during total body irradiation in rats

Melatonin, has been reported to participate in the regulation of a number of important physiological and pathological process. It has also the ability to protect the genetic material of hematopoietic cells of mice from damaging effects of acute total body irradiation. The objective of this study was to the potential radioprotective effects of pharmacological doses of melatonin in total body irradiated rat's peripheral blood cells. Forty adult rats were divided into 4 equal groups. Group 1 received no melatonin or irradiation (control group), while group 2 received only melatonin (5 mg/kg, i.p.). Group 3 received only total body irradiation (RT) by 5 Gy of gamma irradiation only and group 4 received RT plus melatonin (5 mg/kg, i.p., 30 min before RT). An hour and a half following RT, blood samples were taken. Leukocytes and thrombocytes number and hemoglobin levels were measured in all groups. Five mg/kg dose of melatonin significantly protected leukocytes and as well as thrombocytes number against y irradiation. There were no significant differences between Hb levels. Our results suggest that melatonin administration prior to irradiation prevented radiation damage on peripheral blood cells. Melatonin radioprotection is achieved by its ability as a scavenger for free radicals generated by ionizing radiation and acts probably as a growth factor, especially for granulocytes in bone marrow.     

Nitric oxide levels and lipid peroxidation in plasma of patients with gastric cancer

BACKGROUND: The aim was to investigate the levels of malondialdehyde and total NO(2)(-) plus NO(3)(-) marker for NO(*) generation in gastric carcinoma and to correlate their levels with the cancer stage. METHOD: The pretreatment plasma samples were obtained from 38 patients with gastric cancer (seven patients at stage II, 19 at stage III and 12 at stage IV). Nitrite (NO(2)(-)) and nitrate (NO(3)(-)) levels, the end products of nitric oxide (NO(*)), were determined in these samples. NO(2)(-) was measured by using the Griess reaction and after enzymatic conversion of NO(3)(-) into NO(2)(-) by nitrate reductase, the resultant NO(2)(-) was also measured by the same method. Malondialdehyde (MDA), a lipid peroxidation marker, was measured by the thiobarbituric acid method. RESULTS: The levels of plasma MDA, NO(*) and NO(3)(-) were significantly higher in patients with gastric cancer compared with the healthy control group. Higher levels of MDA, NO(*) and NO(3)(-) were observed as the stage of the disease increased. CONCLUSION: We found that increased NO(*) production and MDA levels were present in plasma of patients with gastric cancer. These increases can be associated with the oxidant-antioxidant status in these patients.     

Oxidant/antioxidant status in liver tissue of vitamin B6 deficient rats

BACKGROUND AND AIMS: The aim of this study was to evaluate the lipid peroxidation and antioxidant function in liver tissue of vitamin B6 deficient rats and investigate relationship among these parameters in either group. METHODS: Twenty-four male rats with a weight of 48-59 g were used for the experiment. The rats were divided into control (n=12) and vitamin B6 deficient groups. After 4 weeks of feeding, the rats were killed by cervical dislocation and liver tissues were removed. Biochemical measurements in liver tissue were carried out using a spectrophotometer. RESULTS: Liver tissue antioxidant potential, superoxide dismutase, glutathione peroxidase, glutathione-S-transferase, total (enzymatic plus non-enzymatic) superoxide scavenger activity, non-enzymatic superoxide scavenger activity, glutathione levels were significantly lower in vitamin B6 deficient rats than in control group. However, liver tissue glutathione reductase activity, and MDA values were significantly higher in vitamin B6 deficient rats than in control group. CONCLUSIONS: These results explicitly indicate that vitamin B6 deficiency causes a decrease in antioxidant defense system and an increase in oxidant stress in liver tissue in rats.