Cavernosal tissue nitrite,nitrate, malondialdehyde and glutathione levels in diabetic and non-diabetic erectile dysfunction

The aim of this study is to investigate the role of nitric oxide (NO) stabile end products, membrane lipid peroxidation and antioxidant defensive mechanism in diabetic erectile dysfunction (ED) and compare these parameters with non-diabetic ED groups. We examined the penile cavernosal tissues, obtained from 22 patients who had undergone surgery of penile prostheses implantation, for the nitrite, nitrate, malondialdehyde (MDA) and glutathione (GSH) levels. Eight patients were suffering from diabetic erectile dysfunction (ED) and 14 patients had non-diabetic ED. Nitrite and nitrate levels were lower; MDA and GSH levels were higher in the diabetic group. There were statistically significant differences between diabetic and non-diabetic groups amongst the nitrite (p<0.001), nitrate (p<0.01), MDA (p<0.001) and GSH (p<0.01) levels. Our data provide evidence that NO deficiency, possibly due to the membrane lipid peroxidation and defective antioxidant defensive mechanism, may contribute to the development of diabetic ED and thus is involved in the pathogenesis of ED in diabetic patients.     

Altered antioxidant capacity in human renal cell carcinoma: role of glutathione associated enzymes

PURPOSE: We aimed to discern the role of glutathione (GSH) associated enzymes in maintaining high GSH levels in renal cell carcinoma (RCC) of the clear cell type and analyze RCC enzyme antioxidant capacity. Since changes in cellular redox balance in RCC might also be related to alterations of glutathione S-transferase (GST) phenotype, GST class alpha and pi expression was also explored. METHODS AND MATERIALS: Human kidney specimens of tumor and distant nontumor regions were obtained from 15 patients with RCC at the time of surgery. The activities of GSH-replenishing enzymes, gamma-glutamylcysteine synthetase (gamma-GCS), gamma-glutamyl transferase (gamma-GT), and glutathione reductase (GR), as well as the activities of antioxidant enzymes glutathione peroxidase (GPX) and catalase (CAT) were determined spectrophotometrically. GST alpha and pi class expression was determined by immunoblot. RESULTS: In the course of renal cancerization, significant changes appear in the activities of GSH-replenishing and antioxidant enzymes. The activity of the key enzyme of GSH synthesis, gamma-GCS, is up-regulated (P < 0.001), while the activities of gamma-GT and GR are down-regulated in renal tumors compared to nontumor tissue (P < 0.001 and P < 0.05, respectively). Activities of GPX and CAT were also down-regulated (P < 0.001 and P < 0.05, respectively) in RCC. Changes in enzyme antioxidant capacity in RCC were associated with decreased GST class alpha (P < 0.001) and unchanged GST pi expression at the protein level. CONCLUSIONS: Changes in redox status in RCC as a consequence of decreased enzyme antioxidant capacity, together with altered GST alpha expression, may be important factors in development and tumor growth. The up-regulation of gamma-GCS and high levels of GSH in RCC may be an attempt to limit injury caused by oxidative stress.     

Cavernous antioxidant effect of green tea,epigallocatechin‐3‐gallate with/without sildenafil citrate intake in aged diabetic rats

This study aimed to assess the cavernous antioxidant effect of green tea (GT), epigallocatechin‐3‐gallate (EGCG) with/without sildenafil citrate intake in aged diabetic rats. One hundred and four aged male white albino rat were divided into controls that received ordinary chow, streptozotocin (STZ)‐induced aged diabetic rats, STZ‐induced diabetic rats on infused green tea, induced diabetic rats on epigallocatechin‐3‐gallate and STZ‐induced diabetic rats on sildenafil citrate added to EGCG. After 8 weeks, dissected cavernous tissues were assessed for gene expression of eNOS, cavernous malondialdehyde (MDA), glutathione peroxidase (GPx), cyclic guanosine monophosphate (cGMP), and serum testosterone (T). STZ‐induced diabetic rats on GT demonstrated significant increase in cavernous eNOS, cGMP, GPx and significant decrease in cavernous MDA compared with diabetic rats. Diabetic rats on EGCG demonstrated significant increase in cavernous eNOS, cGMP, GPx and significant decrease in cavernous MDA compared with diabetic rats or diabetic rats on GT. Diabetic rats on EGCG added to sildenafil showed significant increase in cavernous eNOS, cGMP and significant decrease in cavernous MDA compared with other groups. Serum T demonstrated nonsignificant difference between the investigated groups. It is concluded that GT and EGCG have significant cavernous antioxidant effects that are increased if sildenafil is added.     

The effect of prostate cancer and antianrogenic therapy on lipid peroxidation and antioxidant systems

In living organism, excessive free radicals oroxidative damage which occur as a result of deficient antioxidant defensive mechanisms by the effect of endogenous and exogenous factors, influences especially developmental steps of chemically induced cancers [1, 2]. In our study, plasma malondialdehyde level (MDA) as an indicator of lipid peroxidation, erythrocyte glutathione (GSH) level as an indicator of antioxidant state, glutathione reductase (GSH-Red), glutathione peroxidase (GSH-Px), glutathione-S-transferase (GST) as an antioxidant enzymes and plasma vitamin E level were detected in patients with prostate cancer (21 males; age, 69.4 ± 4.8 years) before and after three months of antiandrogenic therapy with goserelin acetate as luteinizing hormone releasing hormone (LHRH) analogue. Healthy people evaluated as a control group (20 males; age, 63.7 ± 3.9). Erythrocyte GSH levels, the activities of GSH-Red and GSH-Px and plasma vitamin E levels were found significantly low in patients with prostate cancer when compared with the healthy subjects (p < 0.01, p < 0.05, p ≤ 0.001 and p ≤ 0.001 respectively). Plasma MDA level and erythrocyte GST activity of patient group were significantly higher than the levels of control group (p ≤ 0.001 and p ≤ 0.001 respectively). After antiandrogenic therapy erythrocyte GSH level, GSH-Red, GSH-Px activity and plasma vitamin E level were found unchanged. Significant decrease in plasma MDA level and significant increase in erythrocyte GST activity were detected in patient group (p < 0.05 and p ≤ 0.01 respectively). The study has revealed the shift in the oxidant-antioxidant balance towards oxidative state in patients with metastatic prostate cancer. Our results showed that antiandrogenic therapy increased in GST activity, decreased in lipid peroxidation. This revised version was published online in August 2006 with corrections to the Cover Date.     

The effect of prostate cancer and antiandrogenic therapy on lipid peroxidation and antioxidant systems

In living organism, excessive free radicals or oxidative damage which occur as a result of deficient antioxidant defensive mechanisms by the effect of endogenous and exogenous factors, influences especially developmental steps of chemically induced cancers. In our study, plasma malondialdehyde level (MDA) as an indicator of lipid peroxidation, erythrocyte glutathione (GSH) level as an indicator of antioxidant state, glutathione reductase (GSH-Red), glutathione peroxidase (GSH-Px), glutathione-S-transferase (GST) as an antioxidant enzymes and plasma vitamin E level were detected in patients with prostate cancer (21 males; age, 69.4 +/- 4.8 years) before and after three months of antiandrogenic therapy with goserelin acetate as luteinizing hormone releasing hormone (LHRH) analogue. Healthy people evaluated as a control group (20 males; age, 63.7 +/- 3.9). Erythrocyte GSH levels, the activities of GSH-Red and GSH-Px and plasma vitamin E levels were found significantly low in patients with prostate cancer when compared with the healthy subjects (p < 0.01, p < 0.05, p < or = 0.001 and p < or = 0.001 respectively). Plasma MDA level and erythrocyte GST activity of patient group were significantly higher than the levels of control group (p < or = 0.001 and p < or = 0.001 respectively). After antiandrogenic therapy erythrocyte GSH level, GSH-Red, GSH-Px activity and plasma vitamin E level were found unchanged. Significant decrease in plasma MDA level and significant increase in erythrocyte GST activity were detected in patient group (p < 0.05 and p < or = 0.01 respectively). The study has revealed the shift in the oxidant-antioxidant balance towards oxidative state in patients with metastatic prostate cancer. Our results showed that antiandrogenic therapy increased in GST activity, decreased in lipid peroxidation.     

The association of oxidant–antioxidant status in patients with chronic renal failure

Oxidative stress has been linked to disease progression, including chronic renal failure (CRF). The aim of the present study was to determine malondialdehyde (MDA) as a sign of lipid peroxidation, and to investigate the association between antioxidant activities and three trace elements, in 49 patients with CRF. The erythrocyte and plasma trace elements [selenium (Se), zinc (Zn), and copper (Cu)] and antioxidant defense levels were determined: glutathione peroxidase (GPx), superoxide dismutase (SOD), catalase (CAT), vitamins E and C. The obtained values were compared with 42 age- and sex-matched healthy controls. There were significantly lower mean values of plasma Se, GPx, vitamins E and C, erythrocyte Se, SOD and CAT levels in the patient group compared to the control group (p?相似文献   

Antioxidant and oxidative stress status in type 2 diabetes and diabetic foot ulcer

OBJECTIVE: Oxidative stress (OS) has been implicated in the aetiology and progression of diabetic complications including diabetic foot ulcer. In this study, the levels of lipid peroxides (LPO) and 8-hydroxy-2'-deoxyguanosine (8-OHdG) as well as the enzymatic antioxidant activities of superoxide dismutase (SOD) and glutathione peroxidase (GPx) in type 2 diabetes mellitus and diabetic foot ulcer subjects were assessed and compared with apparently healthy normal subjects to understand the involvement of OS in the subjects. METHOD: The above-mentioned OS markers were measured in 50 subjects for each of the following groups: type 2 diabetes mellitus (DM), diabetic foot ulcer (DF) and non-diabetic control (NC). RESULTS: Significant elevated values of LPO (39.86%) and 8-OHdG (45.53%) were found in DM subjects compared with the NC subjects. This increase in both parameters was greater for DF subjects: 80.23% and 53.91% respectively. SOD activities were significantly reduced in DM (14.82%) and DF (4.09%) subjects in contrast with elevated activities of GPx observed in DM (21.87%) and DF (20.94%) subjects. Glycated haemoglobin/fasting plasma glucose (HbA1c/FPG) correlated positively with LPO, 8-OHdG and GPx, whereas a negative correlation was observed for SOD. CONCLUSION: Increased oxidation subsequent to diabetic conditions induces an over-expression of GPx activity suggesting a compensatory mechanism by the body to prevent further tissue damage in the subjects.     

Protective effects of trimetazidine on testicular ischemia-reperfusion injury in rats

INTRODUCTION: We tried to prove the effectiveness of trimetazidine (TMZ) on testicular torsion-detorsion injury. MATERIALS AND METHODS: 15 male rats were equally divided into three groups: group 1 was the sham-operated control group; group 2 had 2 h of unilateral testicular ischemia followed by 3 days of reperfusion, and group 3 had 2 h of unilateral testicular ischemia followed by 3 days of oral TMZ treatment (5 mg/kg, bid) during reperfusion. In the removed testicles, tissue reduced glutathione (GSH), glutathione reductase (GR), glutathione peroxidase (GPx), malondialdehyde (MDA) levels and pathological modified Johnson scores (MJS) were evaluated. Mann-Whitney U test was used for statistical evaluations. RESULTS: In group 2, on the ipsilateral side, GSH were significantly lower and MDA were higher than in groups 1 and 3, though GSH and MDA were not statistically different between groups 1 and 3. On the other hand, GPx in the control testicles of group 3 was significantly lower compared to those in the counterparts of both groups 1 and 2. Among three groups, GR determined in both testicles were not statistically different. On the ipsilateral side, MJS in group 3 were lower than in the sham group, but significantly higher than in group 2. CONCLUSIONS: According to this study, TMZ has an antioxidant effect on testicular torsion-detorsion injury, though the protective effect of TMZ seems to decrease in control testicles. Consequently it has been considered that TMZ can be only used in torsion patients with a healthy contralateral testicle after further studies have been conducted.     

Oxidative damage of red blood cells in haemolytic uraemic syndrome

Changes in red blood cell (RBC) lipid peroxidation [measured by malonyl dialdehyde (MDA) concentration], glutathione (GSH) metabolism, antioxidant enzyme activities (catalase, superoxide dismutase, glutathione peroxidase) and haemoglobin (Hb) metabolites (metHb, carboxy Hb) were studied in six children with post-enteropathic (D+) haemolytic uraemic syndrome (HUS) and ten controls. The in vitro effect of hydrogen peroxide [acetyl-phenylhydrazine (APH) test] on GSH and Hb metabolism was also investigated. MDA levels were significantly higher and the antioxidant enzyme activities were lower in HUS patients than in the controls (P<0.01). The oxidised glutathione concentration was significantly higher in the patients than in the control children (26.3±12.6 vs. 10.9±1.8 nmol/g Hb. Percentage values of carboxy Hb and metHb were also higher in HUS (P<0.01). Incubation of RBC with APH induced a more pronounced decrease in the concentration of GSH (P<0.001) and a significant increase (P<0.01) in the level of metHb and carboxy Hb in the HUS patients. This suggests that there is reduced RBC GSH stability in HUS. Utilisation of GSH and antioxidant enzymes leads to increased Hb oxidation and haemolysis. The oxidative damage may have an important role in the pathogenesis of haemolytic anaemia in HUS.     

Protective effects of gallic acid against methotrexate-induced toxicity in rats

Background: Methotrexate, as a chemotherapy drug, can cause chronic liver damage and oxidative stress. Aim of this study was to evaluate the preventive effect of gallic acid (GA) on methotrexate (MTX)-induced oxidative stress in rat liver.

Methods: Twenty-eight male rats were randomly divided into four groups as control, MTX (20?mg/kg, i.p.), MTX?+?GA (30?mg/kg/day, orally) and GA treated. Aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP) were used as biochemical markers of MTX-induced hepatic injury. Malondialdehyde (MDA) and glutathione (GSH) levels and hepatic antioxidant enzymes activities including catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx) were assayed in liver tissue. The expression of SOD2 and GPx1 genes were evaluated by real-time RT-PCR and liver histopathology was evaluated by light microscopy.

Results: The result obtained from current study showed that GA remarkably reduced MTX-induced elevation of AST, ALT and ALP and increased MTX-induced reduction in GSH content, GPx, CAT and SOD activity as well as GPx1 and SOD2 gene expressions. Histological results showed that MTX led to liver damage and GA could improve histological changes.

Conclusions: Our results indicate that GA ameliorates biochemical and oxidative stress parameters in the liver of rats exposed to MTX.     

Glutathione‐S‐transferase‐oxidative stress relationship in the internal spermatic vein blood of infertile men with varicocele

This study aimed to assess glutathione‐S–transferase (GST) enzyme‐ oxidative stress (OS) relationship in the internal spermatic vein (ISV) of infertile men associated with varicocele (Vx). Ninety five infertile oligoasthenoteratozoospemic (OAT) men associated with Vx were subjected to history taking, clinical examination and semen analysis. During inguinal varicocelectomy, GST, malondialdehyde (MDA) and glutathione peroxidase (GPx) were estimated in the blood samples drawn from ISV and median cubital veins. The mean levels of GST, GPx were significantly decreased and the mean level of GPx was significantly increased in the ISV compared with the peripheral blood. The mean level of GST and GPx in the ISV was significantly decreased, and the mean level of MDA was significantly increased in Vx grade III compared with Vx grade II cases. There was nonsignificant difference in the mean level of GST in the ISV in unilateral Vx cases compared with bilateral Vx cases. There was significant positive correlation of GST with sperm count, sperm motility, GPx and significant negative correlation with sperm abnormal forms, MDA. It is concluded that ISV of infertile men associated with Vx has decreased levels of GST compared with peripheral venous circulation that is correlated with both OS and Vx grade.     

Liver injury following renal ischemia reperfusion in rats

Introduction

All transplanted solid organs experience some degree of ischemia-reperfusion (I-R) injury. There is some evidence that I-R injury affects remote organs. We investigated the effects of renal I-R injury on hepatic function, cytochrome P-450 enzymes, and morphology in rats.

Methods

A rat model of 1 hour of renal ischemia followed by 1, 4, or 8 hours of reperfusion. The assays included serum alanine aminotransferase (sALT) aspartate aminotransferase (sAST), cytochrome P-450 enzymes (CYP3A, CYP2E1), hepatic glutathione S-transferase (GST), glutathione (GSH), malondialdehyde (MDA), superoxide dysmutase (SOD), and myeloperoxidase (MPO) activities. In addition, we measured serum blood urea nitrogen (BUN) and serum creatinine (SCr), and renal MDA, glutathione peroxidase levels, and SOD activities. Morphological liver changes were observed by optical and electron microscopy.

Results

sALT and sAST significantly increased after 1 hour of ischemia and 4 or 8 hours of reperfusion. Hepatic CYP3A and CYP2E1 activities were significantly decreased after 1 hour of ischemia and 1 or 4 hours of reperfusion. Hepatic GST, GSH, and SOD activities decreased after renal I-R, while MDA levels and MPO increased. Serum BUN and SCr levels significantly increased after reperfusion. Changes in renal MDA, GSH-px, and SOD activities were similar to those in the liver. The only difference between them was the peak time of injury: for the kidney, 8 hours, while for the liver, some changes appeared at 4 hours. Optical microscopy showed hepatic passive venous congestion and fatty degeneration as well as local necrosis. Transmission electronic microscope showed hepatic cell membrane was damaged, which seemed to explain some data results above. For example, the release of hepatic ALT and AST increased serum ALT and AST. More importantly, the release of neutrophil chemokine induced neutrophil accumulation in the liver, which could cause further damage.

Conclusion

Our findings indicated that hepatic function, cytochrome P-450 enzymes and morphology were affected by renal I-R injury. These effects seemed to be mediated in part by an imbalance of oxidant and antioxidant systems and recruitment of neutrophils to the liver.     

Renoprotection of Kolaviron against benzo (A) pyrene-induced renal toxicity in rats

Abstract

Benzo(a)pyrene (B[a]P), a polycyclic aromatic hydrocarbon generally formed from incomplete combustion of organic matter, reportedly causes renal injury and elicits a nephropathic response. The present study investigated the modulatory effect of Kolaviron, an isolated bioflavonoid from the seed of Garcinia kola, on renal toxicity induced by B[a]P in Wistar rats. Benzo[a]pyrene was administered at a dose of 10?mg/kg alone or in combination with Kolaviron at 100 and 200?mg/kg for 15?d. Administration of B[a]P alone resulted in significant increase in plasma levels of urea and creatinine in the treated rats. Moreover, B[a]P exposure significantly decreased the activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione-s-transferase (GST) as well as glutathione (GSH) level in the kidneys of treated rats. Conversely, myeloperoxidase (MPO) activity, hydrogen peroxide (H₂O₂) and malondialdehyde (MDA) levels were markedly elevated in kidneys of B[a]P-treated rats compared with control. Further, B[a]P exposure significantly decreased the circulatory concentrations of triiodothyronine (T₃) and T₃/T₄ ratio without affecting thyroxine (T₄) in the treated rats. Light microscopy revealed tubular lumen with numerous protein casts in kidneys of rats exposed to B[a]P alone. Kolaviron co-treatment significantly improved the renal antioxidant status, thyroid gland function and restored the renal histology, thus demonstrating the protective effect of Kolaviron in B[a]P-treated rats. Dietary inclusion of Kolaviron could exert protective effects against renal toxicity resulting from B[a]P exposure.     

Ligneous periodontitis and gingival antioxidant status: report of two cases.

Ligneous periodontitis (LP) is a rare periodontal disease in which plasminogen deficiency and fibrin deposition both play a part, resulting in characteristic gingival enlargement and periodontal breakdown. Recent data suggest that oxidant/antioxidant changes are significant in the pathology of oral diseases. This study examines the gingival histopathology in 2 cases with LP. To examine the antioxidant (AO) status, the activity of the major AOs glutathione (GSH), catalase (CAT), and glutathione S-transferase (GST) and the malondialdehyde (MDA) levels, a product of lipid peroxidation, were measured and compared with healthy control subjects. The histopathologic examination of the gingiva revealed subepithelial fibrin accumulation and irregular extensive downward proliferation of the epithelium. Biochemical analysis showed that the CAT, GST, and MDA levels were higher in LP patients than in the control subjects, and the GSH level was lower. Our preliminary findings show that in LP, the AO capacity of the gingiva changes or decreases and lipid peroxidation increases, which suggests that oxidative stress is involved in the pathology of the periodontal breakdown observed in this disease.     

Prophylactic effect of lipoic acid against adriamycin-induced peroxidative damages in rat kidney

Adriamycin (ADR), which is widely used in the treatment of various neoplastic conditions, exerts toxic effects in many organs. The present study was designed to investigate the effect of lipoic acid (LA) against acute ADR induced peroxidative damages in rat kidney. The study was carried out with adult male albino rats of Wistar strain, which comprised of one control and three experimental groups. Group I rats served as controls. Group II rats received ADR (7.5mg/kg body weight) intravenously through the tail vein. Group III rats were given LA (75 mg/kg body weight) intraperitoneally. Group IV rats were given LA one day before the administration of ADR. Rats subjected to ADR administration showed a decline in the thiol capacity of the cell accompanied by high malondialdehyde (MDA) levels along with lowered activities of catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx) glutathione (GSH) and GSH metabolizing enzymes (glutathione reductase (GR), glucose-6-phosphate dehydrogenase (G6PD)). However no significant change was observed in the activity of glutathione-S-transferees (GST). Pretreatment with LA showed considerable changes over oxidative stress parameters. Nephrotoxic damage was evident from the decrease in the activities of gamma-glutamyl transferase (gamma-GT) and beta-glucuronidase (beta-GLU), which were reverted upon LA pretreatment. CONCLUSION: This study has highlighted the beneficial effects of LA pretreatment in reversing the damages caused by ADR, by bringing about an improvement in the reductive status of the cell.     

A time course of contusion-induced oxidative stress and synaptic proteins in cortex in a rat model of TBI

An imbalance between oxidants and antioxidants has been postulated to lead to oxidative damage in traumatic brain injury (TBI). Oxidative neurodegeneration is a key mediator of exacerbated morphological responses and deficits in behavioral recoveries. The present study was designed to delineate the early temporal sequence of this imbalance in order to enhance possible antioxidant therapy. Young adult male Sprague-Dawley rats were subjected to a unilateral moderate cortical contusion. At various times post-trauma (3, 6, 12, 24, 48, 72, and 96 h), animals were killed and the cortex analyzed for enzymatic and non-enzymatic oxidative stress markers. Fresh tissues were prepared for biochemical analysis of several antioxidants (glutathione [GSH], glutathione peroxidase [GPx], glutathione reductase [GR], glutathione-S-transferase [GST], and thiobarbituric acid reactive substances [TBARS]). Synaptic markers Synapsin-I, PSD-95, SAP-97 and GAP-43 were analyzed by Western blot with antibodies directed against them. All activity levels were compared to sham-operated animals. Activity of antioxidant enzymes and GSH clearly demonstrate a significant time-dependent increase in oxidative stress. Changes in pre- and post-synaptic proteins (Synapsin-I and PSD-95) occur early (24 h), whereas SAP-97 levels demonstrate a protracted reduction. These results indicate that depletion of antioxidant systems following trauma could adversely affect synaptic function and plasticity. Because of the observed differences in the time-course of various markers, it may be necessary to stagger selective types of anti-oxidant therapy to target specific oxidative components. The initial therapeutic window following TBI appears relatively short since oxidative damage occurs as early as 3 h.     

Total antioxidant and oxidant status of plasma and renal tissue of cisplatin-induced nephrotoxic rats: protection by floral extracts of Calendula officinalis Linn.

The present study was aimed to determine the total antioxidant status (TAS), total oxidant status (TOS) and oxidative stress index (OSI) of plasma and renal tissue in cisplatin (cDDP) induced nephrotoxic rats and its protection by treatments with floral extracts of Calendula officinalis Linn. Treatment with cDDP elevated (p?p?C. officinalis along with cDDP restored (p?>?0.05) CR, albumin, TOS, GSH and activities of antioxidant enzymes in blood and renal tissue. Ethanolic extract treatments reduced (p?C. officinalis protect cDDP induced nephrotoxicity by restoring antioxidant system of the renal tissue.     

Oxidative stress status and sperm DNA fragmentation in fertile and infertile men

Evidence suggests that disturbing the balance between reactive oxygen species levels and antioxidant contents in seminal plasma leads to oxidative stress resulting in male infertility. This study was carried out to identifying clinical significance of seminal oxidative stress and sperm DNA fragmentation in treatment strategies of male infertility in southwest Iran. Sperm parameters, lipid peroxidation and activity of antioxidant enzymes were assessed in fertile (n = 105) and infertile (n = 112) men. Malondialdehyde (MDA) levels in seminal plasma were found to be higher significantly (p < .001) in patients. Superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities in seminal plasma were significantly (p < .001) lower in infertile men. Significant negative correlations were observed between MDA levels and sperm motility and normal morphology. Spermatozoa with fragmented DNA were higher (p < .001) in infertile men and significantly correlated with MDA levels and SOD and GPx activities. MDA of 4.2 nmol/ml, SOD of 4.89 U/ml and GPx of 329.6 mU/ml were optimum cut‐off limits to discriminate infertile patients from fertile men. The results show the leading role of oxidative stress in aetiology of male infertility in southwest Iran and indicate that evaluation of seminal antioxidant status and DNA integrity can be helpful in men attending infertility clinics during fertility assessment.     

Neuroprotective effects of L-carnitine and vitamin E alone or in combination against ischemia-reperfusion injury in rats

BACKGROUND: Neurological injury because of transient cerebral ischemia is a potential complication of cardiovascular surgery. In this study, the neuroprotective effects of L-carnitine, vitamin E, and the combination of these agents on ischemia/reperfusion (I/R) injury were determined in a rat model of transient global cerebral I/R. METHODS: Rats were pretreated with L-carnitine (100 mg/kg, i.v.) and vitamin E (50 mg/kg, i. v.), alone or in combination and then subjected to cerebral I/R induced by a four-vessel-occlusion technique for a duration of 15 min followed by 15 min of reperfusion. Malondialdehyde (MDA) levels, superoxide dismutase (SOD) activity, and glutathione (GSH) levels were measured in the cerebral tissues. Histopathological examinations were also carried out under light and electron microscopy. RESULTS: The results showed that I/R elevated MDA levels, which were accompanied by a reduction in SOD activities and GSH levels. Surviving neurons was markedly decreased in CA1 and CA3 subfield of hippocampus in I/R animals. L-carnitine, vitamin E, and their combination restored MDA levels and SOD activities, with a tendency to increase surviving neurons in CA1 and CA3 subfield. Combined treatment of L-carnitine and vitamin E had better GSH levels than individual treatment of these agents. CONCLUSIONS: The results suggest that L-carnitine has a potent neuroprotective effect against cerebral-I/R-induced injury in rat brain that is comparable to that of vitamin E. However, the combined use of L-carnitine and vitamin E does not further protect from neuronal injury, although it provides an increase in GSH levels.     

The impact of orthopedic device associated with carbonated hydroxyapatite on the oxidative balance: experimental study of bone healing rabbit model

Orthopedic devices are used in pathologic disorder as an adjunct to bone grafts to provide immediate structural stability. Unfortunately, the use of metallic devices has some complications. This study aimed to characterize the oxidative stress biomarker and the antioxidant enzyme profiles during bone regeneration. New Zealand White rabbits were divided into 4 groups: Group (I) was used as control (T), Groups II, III, and IV were used, respectively, as implanted tissue with carbonated hydroxyapatite (CHA), carbonated hydroxyapatite associated with external fixator (CHA + EF), and presenting empty defects (ED). Grafted bone tissues were carefully removed to measure malondialdehyde (MDA) concentration, superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase activities (GPx). Our results showed that 4 weeks after operation, treatment of rabbits with CHA + EF showed a significantly higher malondialdehyde (MDA) concentration when compared to that of control group. The SOD, CAT, and GPx in CHA + EF group showed significantly lower activities when compared to those in control group. Eight weeks after surgery, the CHA + EF group presented a lower concentration of MDA as compared to those seen after the first 4 weeks after surgery. On the other hand, the SOD, CAT, and GPx showed a higher activity when compared with the same group. Consequently, MDA concentration and the antioxidant enzyme activities were not significant (p > 0.05) when compared to those in control group rabbits. Histologic sampling has demonstrated successful time-patterned resorption accompanied by bone replacement and remodeling. These results suggest that there was a temporary increase in the oxidative marker level in CHA + EF healing bone and the 8-week period was sufficient to re-establish oxidant–antioxidant balance accompanied by bone repair in the tibia rabbit model.