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Purpose: To evaluate DNA damage markers and the antioxidant status of serum and aqueous humor in glaucoma patients., Methods: Aqueous humor and serum samples were obtained at the time of surgery from 28 patients with glaucoma and 27 patients with cataracts. Total antioxidant status (TAS) and 8-hydroxy-2´-deoxyguanosine (8-OHdG) levels of all samples were determined by spectrophotometric and enzyme-linked immunosorbent assay methods., Results: Aqueous levels of 8-OHdG were higher in glaucoma patients than in the cataract group (4.61±2.97 ng/ml versus 1.98±0.70 ng/ml, p=0.002). Serum levels of 8-OHdG were also higher in glaucoma patients than in the cataract group (17.80±8.06 ng/ml versus 13.63±3.54 ng/ml, p=0.046). The TAS levels of serum (0.55±0.13 mmol/lit versus 0.70±0.14, p=0.001), and aqueous humor (0.23±0.13 mmol/lit versus 0.34±0.15, p=0.001) in glaucoma patients were lower than in cataract patients., Conclusions: Our findings provide evidence that oxidative DNA damage increases and TAS decreases in the serum and aqueous humor of glaucoma patients. These findings support the hypothesis that the formation of reactive oxygen species and/or a decrease in TAS may have an important role in the pathogenesis of glaucoma.

Purpose: It was proposed that total thiols (tSH) as powerful reducing agents and oxidized low-density lipoprotein (OX-LDL) may be associated with development of choroidal neovascularization in exudative age-related macular degeneration (E-ARMD)., Methods: In a case-control study, 45 patients with E-ARMD were compared with 45 sex- and age-matched healthy controls. The levels of plasma homocysteine (Hcy) and OX-LDL as oxidant agents, and of tSH and glutathione (GSH) as antioxidant markers, were estimated in E-ARMD patients and controls., Results: The levels of Hcy (15.4±7.2 μM versus 10.7±3.7 μM; p=0.001) and OX-LDL (52.2±13.8 U/l versus 37.8±10.8 U/l; p=0.001) were statistically higher, while GSH (1.10±0.97 μM versus 2.09±1.04 μM; p=0.001) and tSH (0.31±0.06 mM versus 0.35±0.05 mM; p=0.001) were statistically lower, in the patients with E-ARMD than in the control group, respectively. The plasma OX-LDL concentration also exhibited a positive and significant correlation with Hcy (r=0.719, p=0.001) in patients with E-ARMD., Conclusions: Lower GSH and tSH as antioxidant and higher Hcy levels as oxidant agents in E-ARMD patients may have resulted in an oxidative environment that was associated with OX-LDL. Further studies with more cases are required to confirm the hypothesis.

Purpose: This study was designed to evaluate the levels of Interleukin-6 (IL6) and Hepcidin prohormone (Hep) in the serum and aqueous humor of patients with primary open-angle glaucoma (POAG), as well as those with senile cataract as a control group., Methods: Levels of IL6 and Hep were measured by enzyme-linked immunosorbent assay (ELISA) methods in serum and aqueous humor aspirates taken from 45 patients (POAG=20, Control=25) during anterior segment surgery., Results: The mean aqueous humor Hep concentration in eyes with POAG was significantly higher than that controls (34.55±23.01 ng/ml versus 20.82± 24.63 ng/ml, p=0.04). There was no significant difference between the serum Hep concentration of POAG and the control group (359.46±113.03 ng/ml versus 287.36±130.53 ng/ml, p=0.08). There was also no significant difference between either serum (6.18±5.22 versus 10.84±3.37, pg/ml p=0.112) or aqueous humor (4.39±3.06 versus 5.79±2.63, pg/ml p=0.14) IL6 concentrations of POAG and the control groups. No significant correlations were found between aqueous humor and serum Hep and IL6 levels in either POAG or the control groups (p>0.05)., Conclusions: The aqueous humor Hep level may exist locally and independent from the IL6 increase in patients with POAG, suggesting that Hep might represent a bridge protein between local inflammation and the consequent loss of retinal ganglion cells.

Purpose: To evaluate the effects of onion juice on sodium-selenite induced cataract formation., Materials and Methods: Thirty-two 10-day-old Wistar-albino rat pups were divided into four equal groups. Group 1 received only subcutaneous saline injection. In Group 2, sodium-selenite (30 nmol / g body weight) was injected subcutaneously. In Group 3, subcutaneous sodium-selenite was injected and one drop 50% diluted fresh juice of crude onion was instilled every 8 h into the right eye for 14 days; the left eye received no treatment. Group 4 rats were similar to those of Group 3, the only difference being that of undiluted fresh juice of crude onion. The development of cataract was assessed. Rat lenses were analyzed for total antioxidant (TA) level, and for activities of glutathione peroxidase (GPX) and superoxide dismutase (SOD)., Results: Both eyes of all rats in Group 1 did not exhibit cataract formation . In Group 2, all rats developed Grade 3 cataract in the lenses of both eyes. The difference in exhibited cataract in the lens of the right eyes in all rats between Group 2 and any eyes of groups 3 or 4 were significant ( P = 0.001). The mean TA level and mean activities of SOD and GPX in Group 2 rat lenses were significantly lower than the values in lenses of all rats in Group 1 ( P = 0.001, 0.003, 0.001), and in the lenses of the right eyes of rats in Groups 3 and 4 ( P = 0.001, 0.020, 0.001)., Conclusion: Instillation of onion juice into the rat eyes can effectively prevent selenite-induced cataract formation. This effect was associated with increased TA level, SOD and GPX activities in the lens.

Purpose: Elevated levels of lipoprotein(a) [Lp(a)] and homocysteine (Hcy) have been implicated as risk factors for vascular diseases. The study was performed to explore the possible relationship between retinal arteriosclerosis and serum Lp(a) and Hcy levels., Methods: Study subjects consisted of 80 nonsmoking male patients with retinal arteriosclerosis and 54 healthy nonsmoker males as controls. Retinal arteriosclerosis was graded according to the Scheie classification. Serum levels of lipids, lipoproteins, Lp(a), and Hcy were measured by standard methods., Results: The serum level of Hcy was higher in patients (24.2+/-8.1 micromol/l) than controls (10.5+/-4.1 micromol/l); p<0.01. Serum levels of Lp(a) in patients (47.9+/-33.1 mg/dl) was also higher than controls (11.7+/-7.6 mg/dl); p<0.01. There was a significant direct linear correlation between the degree of retinal arteriosclerosis and Lp(a) level (r=0.61, p<0.01), the degree of retinal arteriosclerosis and Hcy level (r=0.72, p<0.01), and also between Lp(a) and Hcy levels (r=0.67, p<0.01)., Conclusions: The association between retinal arteriosclerosis and serum Lp(a) and Hcy levels suggests that Lp(a) as well as Hcy could play a role in the development of retinal arteriosclerosis.

The potential role of exercise in preventing the age-related spontaneous peripheral neuropathy has not been studied. We examined the effects of long-term aerobic exercise training on lipid peroxidation, Schwann cell (SC) apoptosis and ultrastructural changes in the sciatic nerve of rats during aging. Three groups of 12-week old Wistar rats ran on a treadmill for 6, 9 and 12 months (exercise trained (ET) group, n=10 each) according to an exercise training program targeted at a speed of 22 m/min (at 7 degrees incline), 60 min/day, 6 days/week. Three corresponding groups of untrained rats were used as the controls (sedentary (SED) group). At the end of each period, sciatic nerve biopsies were performed, and processed for biochemical, immunohistochemical and ultrastructural analyses. The results showed that aging was associated with an increased level of nerve malondialdehyde (MDA, marker of lipid peroxidation) and a higher number of SC apoptosis in SED group. The SED group showed irregular nerve fibers with thin myelin sheaths and areas of myelin-axon detachment. However, the ET group had significantly diminished nerve lipid peroxidation and SC apoptosis. In the ET group, nerve fibers had a thick myelin sheath with frequent folding. These findings suggest that aerobic exercise training protects peripheral nerves by attenuating oxidative reactions, and preserving SCs and myelin sheath from pathologic changes, which occur during normal aging.

Background: In this study the effect of losartan and enalapril on the reduction of DNA damage was evaluated in regard to renin-angiotensin system (RAS) polymorphisms., Methods: After determination of genotypes of RAS polymorphism by PCR, 64 renal transplant recipients were randomly allocated to one of four groups: the first and second groups were treated with E (E+: 10 mg/day) and L (L+: 50 mg/day) alone, respectively. The third group received E+L (E+L+: 10 + 50 mg/day), and the forth group received no medication (E-L-). The subjects were followed for 8 weeks. After a 2-week washout period, the E group changed to L and vice versa as a cross-over design. They were followed for another 8 weeks. Before and after treatment, we checked 8-OHdG and malondialdehyde (MDA) as biomarkers of DNA damage and lipid peroxidation, respectively., Results: 8-OHdG levels were significantly decreased after treatment in the E+L+ and L+ groups (P < 0.001, P = 0.001, respectively). Only the TT genotype of AGT had the most antioxidative role regarding the treatment (P = 0.01). We found a remarkable correlation between MDA and DNA damage levels before and after intervention (r = 0.48, P < 0.001; r = 0.35, P = 0.006)., Conclusion: The protective effects of L+ and E+L+ on DNA breaks are surprising regarding the RAS polymorphisms.

Introduction: Melatonin, the secretory product of the pineal gland, has potent antioxidant properties. The aim of this study was to compare the effects of low-dose (10 mg/kg) vs high-dose (50 mg/kg) melatonin on early lipid peroxidation levels and ultrastructural changes in experimental blunt sciatic nerve injury (SNI). We believe this to be the first study to assess the dose-dependent neuroprotective effects of melatonin after a blunt peripheral nerve injury., Materials and Methods: Rats were randomly allocated into 5 groups of 10 animals each. The SNI only rats underwent a nerve injury procedure. The SNI plus vehicle group received SNI and intraperitoneal injection of vehicle (diluted ethanol) as a placebo. The SNI plus low-dose or high-dose melatonin groups received intraperitoneal melatonin at doses of 10 mg/kg or 50 mg/kg, respectively. Controls had no operation, melatonin or vehicle injection. SNI was induced by clamping the sciatic nerve at the upper border of the quadratus femoris for 2 min., Results: Sciatic nerve samples were harvested 6 h after nerve injury and processed for biochemical and ultrastructural analysis. Trauma increased the lipid peroxidation of the sciatic nerve by 3.6-fold (153.85 +/- 18.73 in SNI only vs 41.73 +/- 2.23 in control rats, P < 0.01). Low (P = 0.02) and high (P < 0.01) doses of melatonin attenuated the nerve lipid peroxidation by 25% and 57.25%, respectively (65.76 +/- 2.47 in high-dose vs 115.08 +/- 7.03 in low-dose melatonin groups)., Discussion: Although low-dose melatonin reduced trauma-induced myelin breakdown and axonal changes in the sciatic nerve, high-dose melatonin almost entirely neutralized any ultrastructural changes., Conclusion: Our results suggest that melatonin, especially at a dose of 50 mg/kg, has a potent neuroprotective effect and can preserve peripheral neural fibers from lipid peroxidative damage after blunt trauma. With further investigations, we hope that these data may prove useful to clinicians who treat patients with nerve injuries.

Objective: To analyze the role of 3 polymorphisms of the renin-angiotensin system (RAS) in renal transplant recipients (RTRs) and correlate them with graft function., Methods: The present study was performed in the Drug Applied Research Center, Tabriz Medical University, Tabriz, Iran from September 2003 to December 2005 on 108 RTRs (66 males and 42 females, with a mean age of 37.34 +/- 4.97 years) with stable allograft function (creatinine < or =2.2 mg/dl). Following the DNA extraction from the blood leukocytes, the genotypes of the angiotensin converting enzyme (ACE I/D), angiotensinogen (ANG M235T), and angiotensin II type 1 receptor (ATR1 A1166C) were determined by polymerase chain reaction. The magnitude of clearance of creatinine (ClCr) in the setting of each of the above RAS polymorphisms was determined. The ClCr was measured by modification of diet in renal disease formula. Values were expressed as mean +/- SD; p< or =0.05 was considered to indicate statistical significance., Results: There was no association of each genotype of the RAS alone with ClCr, serum urea, cyclosporine through level and the degree of urinary protein excretion rate. However, patients with the DD genotype of angiotensin converting enzyme + CC genotype of angiotensin II type I receptor polymorphisms had lower ClCr (p=0.05) and a higher urinary protein excretion rate (p=0.03). Other combination genotypes of RAS had no effect on allograft function. Interestingly, the percent of hypertensive patients in the C allele (70%) was more than the A allele (30%) of ATR1 polymorphism (p=0.04)., Conclusion: Although none of the single gene polymorphisms of the RAS affected renal allograft function, combinations of these genotypes were associated with the outcome of allograft function.

Objectives: In this study, the effect of enalapril (E) and/or losartan (L) on lipid peroxidation (LPO) is studied in renal transplant recipients (RTRs) with regard to polymorphisms of renin-angiotensin system (RAS)., Design and Methods: After determination of genotypes of the angiotensin-converting enzyme (ACE I/D), angiotensinogen (AGT M235T) and angiotensin II type 1 receptor (ATR1 A1166C) by PCR, sixty-four RTRs recruited to four groups randomly: first (13 patients) and second (20 patients) groups were treated with enalapril (E(+): 10 mg/day) and losartan (L(+): 50 mg/day) alone for 2 months, respectively. After 2 weeks as washout period, E group changed to L and vice versa as a cross-over design and they were treated for another 2 months. The third group (13 patients) as positive control received enalapril+losartan (E(+)L(+): 10 mg/day+50 mg/day) for 16 weeks, and the forth group (18 patients) as negative control received no medication (E(-)L(-)). Malondialdehyde (MDA) as LPO marker was measured before and after treatment. In this study, P<0.05 was considered significant., Results: After 2 months of treatment, MDA level significantly decreased in all of the groups except the E(-)L(-). MDA level in pre- vs. post-intervention for the E(+)L(+), E(+), L(+) and E(-)L(-) groups were as follows: 5.81+/-2.13 nmol/mL vs. 1.61+/-0.80 nmol/mL (P=0.001), 5.10+/-2.05 nmol/mL vs. 1.68+/-1.01 nmol/mL (P=0.003), 5.20+/-1.61 nmol/mL vs. 1.22+/-0.27 nmol/mL (P=0.000) and 5.27+/-2.12 nmol/mL vs. 5.07+/-2.03 nmol/mL (P=0.52), respectively. Also, the same results were found in the end of 16th week. Although patients with DD genotype of ACE had higher MDA (P=0.01) levels, RAS polymorphisms could not predict the antioxidative response rate to the drugs (P>0.05)., Conclusions: E and/or L reduce MDA regardless of the RAS genotypes.

Objective: To determine the susceptibility of low-density lipoprotein (LDL) to oxidation in the plasma of male patients with wet type age related macular degeneration (AMD) and in a similar control group, in order to evaluate the LDL oxidative status as risk factor of AMD., Methods: We conducted this study in the Retina Service, Department of Ophthalmology, Nikookari Eye Hospital-Drug of Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran during the period between October 2004 and December 2005. Sixty male patients with AMD (mean age 67 +/- 16 years) with BMI 4.1 +/- 1.3 were selected as the patient group. The control group consisted of 60 males, apparently healthy, and without ophthalmologic signs and family history of AMD. Low-density lipoprotein was isolated by gradient ultracentrifugation and susceptibility of LDL to in vitro copper-mediated oxidation was assayed by measuring conjugated dienes production (lag phase duration) at 234 nm. Lipid and lipoproteins were determined by standard methods., Results: Comparing with control, significant reduction in the duration of lag phase (p<0.004) and a significant increase in LDL-C concentrations (p=0.006), were noticed. No significant change in cholesterol (p>0.3), triglyceride (p>0.1) and high density lipoprotein cholesterol (p>0.1) levels were found between control and patient groups. A significant negative correlation between Lag phase and LDL-C levels (p=0.004, r=-0.364) was found in the patient group., Conclusion: The increased LDL concentration and enhanced susceptibility of LDL to oxidation may play a roll in the wet type AMD process.