Inhibition of inducible nitric oxide synthase prevents shock wave therapy induced renal injury.

OBJECTIVES: Shock wave lithotripsy treatment (SWT) is not completely free from side effects; one of the accused mechanisms for renal injury during SWT is oxygen- and nitrogen-derived free radical productions. Therefore, we aimed to evaluate the effect of inhibition of nitric oxide (NO) production by N-[3(aminomethyl) benzyl) acetamidine] (1400W), highly selective inducible nitric oxide synthase (iNOS) inhibitor, at SWT-induced kidney damage. MATERIALS AND METHODS: Twenty-four rats those underwent right nephrectomy procedure were divided equally into three groups as control, SWT, and SWT + 1400W. 1400W was administered at a dose of 10 mg/kg at 2 h prior to SWT procedure and at the beginning of SWT procedure via intraperitoneal route and continued daily for consecutive 3 days. At the end of the fourth day, animals were killed via decapitation and trunk blood and the left kidneys were taken for biochemical and histopathologic evaluation. RESULTS: SWT caused renal tubular damage and increased lipid peroxidation and antioxidant enzyme activities and SWT also significantly increased nitro-oxidative products. Inhibition of iNOS via administration of 1400W ameliorated renal injury and decreased tissue lipid peroxidation (malondialdehyde), superoxide dismutase, glutathione peroxidase and nitrite/nitrate levels (NOx). In addition, it was seen that histolopathological changes were attenuated in the SWT + 1400W group when compared to SWT group. CONCLUSION: SWT-induced renal injury might be due to excessive production of oxygen free radicals and NO production. Inhibition of iNOS attenuates renal injury following SWT treatment. It can be concluded that iNOS inhibitors or peroxynitrite scavengers might be used to protect the kidneys against SWT-induced morphological and functional injuries.

Protective effects of melatonin and S-methylisothiourea on mechlorethamine induced nephrotoxicity.

BACKGROUND: In this study, we aimed to investigate the protective effects of melatonin (MEL) and S-methylisothiourea (SMT) on mechlorethamine (MEC) induced nephrotoxicity. MATERIALS AND METHODS: A total of 36 male Sprague-Dawley rats were divided into four groups: control, MEC, MEC+MEL, and MEC+SMT. Three groups received single dose of MEC (3.5 mg/kg) via transdermal route. Control animals were given saline only via transdermal route. MEL (100 mg/kg) was administered intraperitoneally 30 min after the application of MEC, and after the same dose of MEL was given every 12 h for a total of six doses. SMT (50 mg/kg) was also given intraperitoneally 30 min after the application of MEC. RESULTS: The tissue TNF-α, IL-1ß, and NOx levels were found significantly different for all groups (P < 0.001). MEC application resulted in severe histopathological changes. Melatonin showed meaningful protection against kidney damage. But protection by SMT was weaker. TNF-α and IL-1ß levels increased significantly with MEC application, and MEL and SMT ameliorated these increases in kidney tissue. MEC also elevated NOx levels in kidney tissue. CONCLUSIONS: Both inflammation and oxidative stress may have an important role in the MEC induced nephrotoxicity. MEL and SMT may also have anti-inflammatory properties, as well as anti-oxidant properties.

The effects of medical ozone therapy on renal ischemia/reperfusion injury.

INTRODUCTION: This study was designed to investigate the possible beneficial effects of medical ozone therapy (OT), known as an immunomodulator and antioxidant, on the renal function, morphology, and biochemical parameters of oxidative stress in kidneys subjected to ischemia/reperfusion injury (IRI). MATERIALS AND METHODS: Thirty male Sprague-Dawley rats were classified into three groups: control, renal IRI, and renal IRI + OT. The IRI group was induced by bilateral renal ischemia for 60 min, followed by reperfusion for 6 h. After reperfusion, the kidneys and blood of rats were obtained for histopathologic and biochemical evaluation. RESULTS: Renal IRI increased the tissue oxidative stress parameters (lipid peroxidation, protein oxidation, and nitrite plus nitrate) and decreased the antioxidant enzyme activities (superoxide dismutase and glutathione peroxidase). The serum neopterin levels showed correlation with oxidative stress parameters. All these parameters were brought to control values in the treatment group. Histopathologically, the kidney injury in the treatment group was significantly lesser than in the renal IRI group. CONCLUSIONS: Our results clearly showed that OT has beneficial effect to protect kidney against IRI. The serum neopterin levels might be used as a marker to detect the degree of renal IRI.

Simultaneous determination of cyclosporine A, tacrolimus, sirolimus, and everolimus in whole-blood samples by LC-MS/MS.

OBJECTIVES: Cyclosporine A (CyA), tacrolimus (TRL), sirolimus (SIR), and everolimus (RAD) are immunosuppressive drugs frequently used in organ transplantation. Our aim was to confirm a robust sensitive and selective liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for determination of CyA, TRL, SIR, and RAD in whole-blood samples. MATERIALS AND METHODS: We used an integrated online solid-phase extraction-LC-MS/MS system and atmospheric pressure ionization tandem mass spectrometry (API-MS/MS) in the multiple reaction monitoring (MRM) detection mode. CyA, TRL, SIR, and RAD were simultaneously analyzed in whole blood treated with precipitation reagent taken from transplant patients. RESULTS: System performance parameters were suitable for using this method as a high-throughput technique in clinical practice. The high concentration of one analyte in the sample did not affect the concentration of other analytes. Total analytical time was 2.5 min, and retention times of all analytes were shorter than 2 minutes. CONCLUSION: This LC-MS/MS method can be preferable for therapeutic drug monitoring of these immunosuppressive drugs (CyA, TRL, SRL, and RAD) in whole blood. Sample preparation was too short and simple in this method, and it permits robust, rapid, sensitive, selective, and simultaneous determination of these drugs.

Plasma asymmetric dimethylarginine (ADMA) concentrations in patients with first and multiple episode schizophrenia.

An increasing number of reports in the literature indicate that asymmetric dimethylarginine (ADMA) regulates nitric oxide generation in numerous disease states. ADMA has been less studied in psychiatric disorders. The purpose of this study was to determine plasma ADMA concentrations in patients with schizophrenia compared to healthy controls. The study was conducted in 49 male patients with schizophrenia and 30 healthy male control subjects. The patient group was 24 first episode and 25 multiple episode schizophrenia participants. All schizophrenic patients were administered the Scale for the Assessment of Negative Symptoms, the Scale for the Assessment of Positive Symptoms (SAPS) and the Brief Psychiatric Rating Scale. Measurement of plasma concentrations of ADMA was accomplished by HPLC. There was a significant increase in the plasma ADMA concentrations in patients with schizophrenia when compared to healthy controls. There were no significant correlations between the plasma concentrations of ADMA and scores of psychiatric rating scales. In the multiple episode schizophrenia subgroup, the mean plasma ADMA concentration was significantly higher than in the first episode schizophrenia subgroup. The study indicate that plasma ADMA concentrations in patients with schizophrenia are elevated.

The role of preconditioning and N-acetylcysteine on oxidative stress resulting from tourniquet-induced ischemia-reperfusion in arthroscopic knee surgery.

BACKGROUND: The aim of this study was to investigate the effects of ischemic preconditioning (IPC) and N-acetylcysteine (NAC) on oxidative stress resulting from tourniquet-induced ischemia-reperfusion (IR) period in arthroscopic knee surgery. METHODS: Forty-five patients who had arthroscopic knee surgery for meniscal and chondral lesions and for pathologic medial plica were included in this study. They were assigned to the following treatment groups: control (group C; n=15), IPC (group P; n=15), and NAC (group N; n=15). Subjects in the control group underwent routine surgical procedures. Subjects in the preconditioning group were subjected to temporary ischemia, with tourniquet performed by three compression cycles of 5 minutes followed by 5 minutes of reperfusion just before the application of tourniquet inflation. Subjects in the NAC group received 10 mg/kg NAC dissolved in 100 mL 0.9% normal saline intravenously 30 minutes before tourniquet inflation. An hour before the tourniquet was applied (preischemia) and 2 hours after tourniquet was removed (reperfusion), blood samples (to test for metabolites) were obtained. Levels of malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), total antioxidant capacity (TAC), and total oxidant status (TOS) were measured in all serum samples. Results were compared between preischemia and reperfusion in three groups. RESULTS: MDA in the control group was found to be increased significantly compared with preischemia, whereas MDA in IPC and NAC groups did not change insignificantly. SOD and GSH activities in the control group were found to be increased significantly, whereas SOD and GSH activities in IPC and NAC groups did not change significantly after reperfusion. TAC in the control group was found to be decreased and TOS was found to be increased significantly, but TAC and TOS in IPC and NAC groups were not significantly different after reperfusion. Mean serum MDA, TOS, SOD, and GSH-Px levels were lower in group P than group C at reperfusion period (p<0.05). Mean serum SOD levels were lower in group P than group N at reperfusion period (p<0.05). CONCLUSIONS: Tourniquet-induced IR period in routine arthroscopic knee surgery resulted in oxidative stress by increasing MDA, SOD, GSH-Px, TOS and decreasing TAC. NAC and IPC had protective effect on occurrence of oxidative stress resulting from IR period by preventing MDA, SOD, GSH-Px, TAC, and TOS changes in routine arthroscopic knee surgery.

The levels of nitric oxide and asymmetric dimethylarginine in the rat endometriosis model.

AIM: To investigate the levels of nitric oxide (NO) and asymmetric dimethylarginine (ADMA) in all the rat endometriosis models. MATERIAL & METHODS: Forty-one rats with endometriotic implants were divided into four groups (1 to 4) and administered infliximab, etanercept, letrozole and control, respectively. There were 11 rats in group 5 (normal). The size of implants, plasma ADMA and nitrate/nitrite (NO(x) ) levels and histological score were assessed. RESULTS: In groups 1, 2 and 3, plasma ADMA levels were higher than groups 4 and 5, 296.8 ± 66.2, 285.9 ± 35.7, 200.3 ± 41.0, 125.3 ± 16.7, 111.3 ± 6.5 µmol/L, respectively, while NO(x) levels were lower than groups of control and normal 19.6 ± 3.8, 19.8 ± 4.4, 39.3 ± 6.1, 80.5 ± 5.3, and 91.1 ± 5.0 µmol/L, respectively. CONCLUSIONS: Infliximab, etanercept and letrozole have regressed endometriotic implants, decreased plasma NO(x) levels, and increased plasma ADMA levels.

Effect of preconditioned hyperbaric oxygen and ozone on ischemia-reperfusion induced tourniquet in skeletal bone of rats.

BACKGROUND: The aim of the study was to investigate effect of I/R injury on bone tissue and protective role of hyperbaric oxygen precondition (HBO-PC) and ozone precondition (O(3)-PC) on I/R injury by using biochemical analysis. MATERIALS AND METHODS: Thirty-two rats were included in study. The animals were divided into four equal groups: sham operation, I/R, I/R+HBO and I/R+O(3). One session of 60 min, 3 ATA, 3-4 L/min, 100% oxygenation was defined as one dose of HBO. First dose of HBO was administrated 72 h before ischemia. Subsequent, one-dose of HBO administrated per 12 hours until ischemia time (total seven doses); 0.7 mg/kg ozone/oxygen mixture intraperitoneally was defined as one dose of ozone. First dose of O(3) was administered 72 h before ischemia (total four doses). I/R model was induced in anesthetized rats by unilateral (right) femoral artery clipping for 2 h followed by 22 h of reperfusion. The right tibia and were harvested. Tissue was assayed for levels of malondialdehyde (MDA) and protein carbonyl (PCO), activities of superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px). RESULTS: MDA and PCO levels were increased in I/R group. SOD activity was increased; GSH-Px activity was decreased in I/R group. MDA and PCO levels were decreased, SOD and GSH-Px activities were increased in both HBO+I/R and O(3)+I/R groups. CONCLUSION: It has been shown that levels of MDA and PCO in bone were increased followed by 2 h of ischemia and 22 h of reperfusion period. Ozone-PC and HBO-PC has protective effect against skeletal bone I/R injury by decreasing levels of MDA and PCO, increasing activities of SOD and GSH-Px in rats.

Comparison of the effect of topical and systemic melatonin administration on delayed wound healing in rats that underwent pinealectomy.

OBJECTIVES: Melatonin is a hormone which has many systemic effects in addition to its strong antioxidant properties. The aim of the present study was to investigate the difference between sytemic and topical administration of melatonin by forming a chronic wound model in rats whose release of basal melatonin was supressed by pinealectomy. MATERIAL AND METHODS: Experimental animals used in the study were divided into four equal groups: (i) a group of normal animals with wound formation (control), (ii) a group of animals who underwent pinelaectomy and wound formation (PINx), (iii) a group that underwent PINx + systemic melatonin administration, and (iv) a group that underwent PINx + topical melatonin administration. Fifteen days after pinealectomy, a bipediculed flap was formed on the back of the rats under anesthesia and then six excisional skin wounds were produced in all groups. Following the treatment that lasted 7 days, on day 8 the wound surface areas were measured and wound tissues were removed under anesthesia. In these tissues the levels of malondialdehit (MDA) and hydroxyproline (OH-proline) and the activities of superoxide dismutase(SOD) and glutathion peroxidase (GSH-Px) were measured. RESULTS: In the PINx group, OH-prolin levels decreased significantly compared to the control group and wound surface areas increased. MDA levels increased compared to the control group, and SOD and GSH-Px decreased accordingly. Conversely, in two melatonin groups in which melatonin was administered systemically or topically MDA decreased while SOD ve GSH-Px enzymes increased. CONCLUSION: In conclusion, in the present study it was shown that wound healing was prolonged in experimental animals deprived of melatonin through pinealectomy. Melatonin exerts positive effects on wound healing, whether it is administered topically or systemically.

Comparison of the efficacy of melatonin and 1400W on renal ischemia/reperfusion injury: a role for inhibiting iNOS.

INTRODUCTION: We investigated the roles of melatonin (a powerful antioxidant, iNOS inhibitor, and a scavenger of peroxynitrite) and 1400W (a strong and selective inhibitor of inducible nitric oxide) on renal dysfunction and injury induced by ischemia/reperfusion (I/R) of rat kidney, since oxidative and nitrosative injury are believed to be the major causes. MATERIALS AND METHODS: Thirty-two male Sprague-Dawley rats were divided into four groups of sham-operated, I/R, I/R + Melatonin and I/R + 1400W. Rats were given either melatonin (10 mg/kg) or 1400W (10 mg/kg) in the I/R + Melatonin and I/R + 1400W groups respectively at 6 h prior to ischemia and at the beginning of reperfusion via intraperitoneal route. I/R injury was induced by 60 min of bilateral renal ischemia followed by 6 h of reperfusion. After reperfusion, kidneys and blood were obtained for histopathologic and biochemical evaluation. RESULTS: Melatonin and 1400W had an ameliorative effect on both oxidative and nitrosative stress in the kidneys against renal I/R injury in rats. In addition, melatonin significantly reduced elevated nitro-oxidative stress product, restored decreased antioxidant enzymes and attenuated histological alterations when compared with 1400W. CONCLUSIONS: Both Melatonin and 1400W were efficient in ameliorating experimental I/R injury of the kidneys. Moreover, melatonin was more effective than 1400W possibly through inhibiting iNOS as well as scavenging free oxygen radicals and peroxynitrite.

3-aminobenzamide, a poly ADP ribose polymerase inhibitor, attenuates renal ischemia/reperfusion injury.

INTRODUCTION: This study was designed to investigate whether 3-amino benzamide (3-AB), a poly (ADP-ribose) polymerase (PARP) inhibitor, has a protective effect on kidney injury induced by renal ischemia/reperfusion (I/R) by decreasing oxidative and nitrosative stress on renal dysfunction and injury. MATERIALS AND METHODS: Thirty-two male Sprague-Dawley rats were divided into four groups: sham-operated, sham-operated + 3-AB, I/R, I/R + 3-AB. Rats were given 3-AB (100 mg/kg/day ip) 14 days prior to I/R. I/R and I/R + 3-AB groups underwent 60 min of bilateral renal ischemia followed by 6 h of reperfusion. After reperfusion, kidneys and blood were obtained for evaluation. Superoxide dismutase, glutathione peroxidase, malondialdehide, protein carbonyl content, and nitrite/nitrate level (NO(x)) were determined in the renal tissue. Serum creatinine (S(Cr)), blood urea nitrogen (BUN), and aspartate aminotransferase (AST) were determined in the blood. Additionally, renal sections were used for histological grade of renal injury. RESULTS: 3-AB significantly reduced the I/R-induced increases in S(Cr), BUN, and AST. In addition, 3-AB markedly reduced elevated oxidative stress product, restored decreased antioxidant enzymes, and attenuated histological alterations. Moreover, 3-AB attenuated the tissue NO(x) levels, indicating reduced NO production. CONCLUSIONS: 3-AB has beneficial effect on renal glomerular and tubular dysfunction in rats' kidneys subjected to I/R injury. Moreover, 3-AB has ameliorating effect on both oxidative stress and nitrosative stress of the kidneys, which correlated with histopathological evaluation.

Do zinc and selenium prevent the antioxidant, hepatic and renal system impairment caused by aspirin in rats?

Aspirin is widely used as an antiinflammatory drug especially in children with rheumatic fever arthritis. The diminishing effects of aspirin on antioxidant enzymes and hepato-renal systems at high doses are well-known. It is now evident that the damage at antioxidant system worsens the clinical picture of the disease and prolongs the treatment time. Thus, we investigated the effect of antioxidant enzyme cofactors-zinc and selenium-supplementation on superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and malondialdehyde (MDA) levels (erythrocyte and liver) and hepato-renal toxicity during aspirin treatment at therapeutic doses. The rats were divided into five groups. The first and second groups were given aspirin 75 mg/kg/day and aspirin plus selenium (Selenium 200, selenium 200 mg tablet as selenium yeast, GNC) and zinc (Zinc 100, zinc 100 mg tablet as zinc gluconate, GNC), respectively, the third and fourth take 50 mg/kg/day aspirin and aspirin plus selenium and zinc twice a day, respectively. The fifth group was control. The rats were treated with aspirin for 5 weeks as in the treatment of rheumatic fever arthritis in children. Erythrocyte SOD and MDA levels were preserved with supplementation, whereas there was no change for GSH-Px levels. Liver SOD, GSH-Px, and MDA levels were not changed. In zinc- and selenium-supplemented groups, the levels of serum alanine aminotransferase, uric acid, and direct bilirubin levels were found statistically decreased compared with nonsupplemented groups. There was no significant histopathologic change in specimens of hepatic and renal tissues. Trace element supplementation may prevent free radical damage and shorten treatment time in children using long-term aspirin treatment.