Effect of methoxychlor on antioxidant system of goat epididymal sperm in vitro

Aim: To evaluate the effect of methoxychlor on the antioxidant system of goat epididymal sperm. Methods: Epididymis of adult goat was obtained from local slaughter houses and sperm were collected by chopping the epididymis in modified Ringer‘s phosphate solution (RPS). After several washings, the sperm samples were dispersed in RPS and incubated with methoxychlor (1μmol/L, 10 μmol/L and 100 μmol/L) and methoxychlor vitamin C (100 μmol/L each) for 3 h at 32℃. After incubation, the sperm motility and viability were assessed. An aliquot of sperm sample was homogenized, centrifuged and used for the assay of superoxide dismutase, glutathione peroxidase, glutathione reductase and lipid peroxidation. Results: In methoxychlor-mcubated sperm and in sperm co-incubated with methoxychlor and vitamin C, the sperm motility and viability showed no significant changes as compared to the corresponding controls. In methoxychlor-incubated sperm the activity of superoxide dismutase, glutathione reductase and glutathione peroxidase were decreased while lipid peroxidation was increased in a dose-dependent manner. Co-incubation of sperm with methoxychlor and vitamin C showed no changes in the activity of superoxide dismutase, glutathione reductase and glutathione peroxidase and in the level of lipid peroxidation. Conclusion: Methoxychlor induced oxidative stress in epididymal sperm of goats by decreasing the levels of antioxidant enzymes. Co-incubation of sperm with methoxychlor and vitamin C, a natural antioxidant, reversed the effect of methoxychlor.     

Effect of lindane on antioxidant enzymes in epididymis and epididymal sperm of adult rats

Aim: To find out the changes induced by lindane on the antioxidant enzymes in epididymis and epididymal sperm of adult rats. Methods: Adult male rats were orally administered lindane at a dose of 5.0 mg/kg body weight per day for 30 days. At the end of the treatment, the rats were sacrificed. The epididymis was removed and weighed and sperm were collected for sperm count, motility and biochemical studies. A 1% homogenate of epididymis was prepared and used for biochemical estimations. Results: In lindane-treated rats, there were significant reductions in the epididymal weight, epididymal sperm count and motility compared with the controls. Significant decreases in the superoxide dismutase (SOD), catalase, glutathione reductase and glutathione peroxidase activities and significant increases in the H2O2 generation and lipid peroxidation were also observed in the epididymis and epididymal sperm of lindane-treated rats. Conclusion: Lindane decreases the levels of antioxidant enzymes in the epididymis and epididymal sperm of adult rats thereby inducing oxidative stress.     

Effect of piperine on the epididymis of adult male rats

Aim： To study the effect of piperine on the epididymal antioxidant system of adult male rats. Methods： Adult male rats were orally administered piperine at doses of 1 mg/kg, 10 mg/kg and 100 mg/kg body weight each day for 30 consecutive days. Twenty-four hours after the last treatment, the rats were weighed and killed with ether and the epididymis was dissected from the bodies. Sperm collected from the cauda region of the epididymis was used for the assessment of its count, motility and viability. Caput, corpus and cauda regions of the epididymis were separated and homogenized separately to obtain 10 % homogenates. The supernatants were used for the assays of sialic acid, superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, lipid peroxidation and hydrogen peroxide generation. Results： Body weight of the piperine-treated rats remained unchanged. The weights of the caput, corpus and cauda regions of the epididymis significantly decreased at dose of 100 mg/kg. Epididymal sperm count and motility decreased at 10 mg/kg and 100 mg/kg, and sperm viability decreased significantly at 100 mg/kg. Sialic acid levels in the epididymis decreased significantly at 100 mg/kg while significant decrease in the cauda region alone was observed at 10 mg/kg. A significant decline in the activities of superoxide dismutase, catalase, glutathione peroxidase and glutathione reductase, along with an increase in hydrogen peroxide generation and lipid peroxidation were observed at 10 mg/kg and 100 mg/kg. Conclusion： Piperine caused a decrease in the activity of antioxidant enzymes and sialic acid levels in the epididymis and thereby increased reactive oxygen species levels that could damage the epididymal environment and sperm function.     

Quercetin exacerbates the effects of subacute treatment of atrazine on reproductive tissue antioxidant defence system,lipid peroxidation and sperm quality in rats

The study investigated the reproductive function and the antioxidant defence system of rats co‐exposed to atrazine [ATZ, 120 mg kg^?1 body weight (b. wt)] and quercetin (QT, 20 mg kg^?1 b. wt.). ATZ had no significant effects on feed intake, body weights and reproductive organs weight except prostate weight. Sperm abnormalities were increased, whereas sperm production, sperm motility and epididymal and testicular sperm numbers were decreased with ATZ treatment. Antioxidant enzymes including superoxide dismutase, glutathione‐S‐transferase and glutathione peroxidase were significantly altered in the epididymis and testis resulting to lipid peroxidation. A potentiating response on glutathione‐S‐transferase and aspartate aminotransferase activities in the testis and on lactate dehydrogenase activity and glutathione level in the epididymis was observed in the QT + ATZ animals. Quercetin alone decreased seminal vesicle and prostate weights, increased superoxide dismutase activity in the testis and ascorbate level in the epididymis. Mild pathological changes were observed in the ATZ group, whereas considerable necrosis of seminiferous tubular cells with hypoplasia of the epithelia was observed in the QT + ATZ animals. The epididymis of these animals had multilayered and sometimes a single lining epididymal epithelium with few spermatozoa. We conclude that quercetin at the investigated dose increases the susceptibility of rat reproductive tissues to atrazine‐induced oxidative damage.     

Evidence for increased lipid peroxidative damage and loss of superoxide dismutase activity as a mode of sublethal cryodamage to human sperm during cryopreservation.

Cryopreservation of human sperm, now generally required in donor insemination programs, adversely affects the sperm in terms of standard sperm evaluation parameters and fertilizing ability. The freeze-thaw process appears to produce sublethal damage that appears only after a delay. The authors hypothesized that cryopreservation enhanced peroxidation of sperm membrane lipids, based on previous studies of sperm lipid peroxidation, which showed that the effects of peroxidative damage became evident only after a delay, depending on the peroxidation rate. The effect of cryopreservation on the phospholipid content, the composition of the acyl moieties of the phospholipids, and the activities of the peroxidation protective enzymes, superoxide dismutase (SOD) and glutathione peroxidase plus reductase, in human sperm were examined to test the hypothesis. Parallel determinations were made of the percent motility, the average path velocity of the motile cells, and the time to loss of motility under specified aerobic incubation conditions, which gives a good estimate of the lipid peroxidation rate. The phospholipid content decreases after cryopreservation, with loss of phosphatidylcholine and phosphatidylethanolamine being the more pronounced. Polyunsaturated acyl moieties were also preferentially lost. This loss pattern is observed also from lipid peroxidation. The activities of glutathione peroxidase plus reductase remained unchanged. The sperm SOD activities varied widely between samples before cryopreservation. In all samples there was a decline in SOD activity after freeze-thaw, but the extent of the decline was also widely variable. The time to loss of motility declined in parallel with SOD activity, and a strong correlation (R2 greater than 0.9) between SOD activity and time to loss of motility was found for all samples, before and after freeze-thaw. The authors conclude that cryopreservation does enhance lipid peroxidation in human sperm, as hypothesized, and that this enhancement is mediated at least in part by the loss of SOD activity occurring during the process.     

Lipid peroxidation and antioxidant enzymes in synovial fluid of patients with primary and secondary osteoarthritis of the knee joint

OBJECTIVE: Osteoarthritis of the knee (KOA) is a common, age-related, joint disorder associated with loss of articular cartilage, osteophyte formation, sub-chodral bone change and synovitis. Recent studies have shown that reactive oxygen species (ROS) may participate in the initiation and progression of KOA. This study examines potential changes in the activities of antioxidant enzymes (superoxide dismutase, both isoenzymes zinc-copper superoxide dismutase and manganese superoxide dismutase) and glutathione transformation enzymes (glutathione peroxidase, glutathione reductase and glutathione-S-transferase) in synovial fluid of KOA patients, and estimates their relationship to the degree of lipid peroxidation in synovial fluid evaluated by malondialdehyde concentration, synovial fluid viscosity, type and duration of KOA. DESIGN: Synovial fluid samples obtained by transdermal arthrocentesis from 41 patients with KOA (23 had primary KOA and 18 had secondary KOA) and 22 control subjects were analyzed. Activities of antioxidant enzymes were analysed with the use of kinetic method, MDA concentration was measured fluorometrically by the Ohkawa method, and synovial fluid viscosity was measured using a cone-late viscometer Brookfield DV-II+ and a test by Ropes. RESULTS: Patients with KOA had significantly increased activities of all enzymes when compared to the control subjects for both KOA subgroups. The synovial fluid viscosity was significantly decreased and the synovial fluid test by Ropes was abnormal in KOA patients, mainly in the secondary KOA subgroup. The activities of all antioxidant enzymes were significantly negatively correlated with synovial fluid viscosity and duration of KOA. CONCLUSIONS: Patients with KOA display abnormal antioxidant status of synovial fluid with increased activities of antioxidant enzymes and decreased synovial fluid viscosity. Furthermore, synovial fluid viscosity, and activity of GR can be used to distinguish the primary from the secondary type of KOA.     

Antioxidative potential of Quercetin against hydrogen peroxide induced oxidative stress in spermatozoa in vitro

This study was carried out to test the antioxidant effects of Quercetin on sperm parameters and antioxidant enzymes in male rats assessed in vitro after H(2) 0(2) -mediated sperm oxidative damage. Spermatozoa were incubated with Quercetin (10, 100 and 200 μm), H(2) O(2) alone (100 μm) and Quercetin (100, 200 μm) + H(2) O(2) (100 μm) repectively, for 3 h at 32 °C. After that, sperm parameters (motility, viability and abnormal morphology), malondialdehyde, superoxide dismutase, catalase and glutathione peroxidase levels were determined. We found that exposure to H(2) O(2) let to significant increase in lipid peroxidation (LP) and abnormal morphology associated with significant decrease in sperm motility, viability and antioxidant enzymes activities. When Quercetin was added in culture medium, it improved activities of antioxidant enzymes and protected spermatozoa against the deleterious effect of H(2) O(2) on sperm parameters and LP. This study demonstrated that supplementation with Quercetin could protect spermatozoa against H(2) O(2) -mediated sperm damage.     

Melatonin prevents gentamicin‐induced testicular toxicity and oxidative stress in rats

This study investigated the protective effects of melatonin (MT) against gentamicin (GM)‐induced testicular toxicity and oxidative damage in rats. GM (100 mg kg^?1) was injected intraperitoneally (i.p.) to rats for 6 days. MT (15 mg kg^?1) was administered i.p. to rats for 6 days at 1 hr after the GM treatment. GM caused a decrease in prostate and seminal vesicle weights, sperm count and sperm motility. Histopathological examination showed various morphological alterations in the testis, characterised by degeneration of spermatogonia/spermatocytes, decrease in the number of early spermatogenic cells and vacuolisation. In addition, an increased malondialdehyde concentration and decreased glutathione content and glutathione reductase, catalase and glutathione‐S‐transferase activities were found in the testis. In contrast, MT treatment significantly attenuated the testicular toxicity of GM, including decreased reproductive organ weights, sperm count, and sperm motility and increased histopathological alterations. MT also had an antioxidant benefit by decreasing the lipid peroxidative product malondialdehyde and increasing the level of the antioxidant glutathione and the activities of antioxidant enzymes in the testis. These results indicate that MT prevents testicular toxicity induced by GM in rats, presumably due to its potent antioxidant activity, and its ability to inhibit lipid peroxidation, and restore antioxidant enzyme activity.     

Melatonin attenuates doxorubicin-induced testicular toxicity in rats

This study investigated the protective effects of melatonin (MLT) against doxorubicin (DXR)-induced testicular toxicity and oxidative stress in rats. DXR was given as a single intraperitoneal dose of 10 mg kg(-1) body weight to male rats at 1 h after MLT treatment on day 6 of the study. MLT at 15 mg kg(-1) body weight was administered daily by gavage for 5 days before DXR treatment followed by an additional dose for 5 days. Sperm analysis, histopathological examination and biochemical methods were used for this investigation. DXR caused a decrease in the weight of seminal vesicles, epididymal sperm count and motility and an increase in the incidence of histopathological changes of the testis. In addition, an increased malondialdehyde (MDA) concentration and decreased glutathione content, glutathione reductase (GR), glutathione-S-transferase (GST), superoxide dismutase (SOD) and catalase activities were observed. On the contrary, MLT treatment significantly ameliorated DXR-induced testicular toxicity in rats. Moreover, MDA concentration and GR, GST and SOD activities were not affected when MLT was administered in conjunction with DXR. These results indicate that MLT had a protective effect against DXR-induced testicular toxicity and that the protective effects of MLT may be due to both the inhibition of lipid peroxidation and increased antioxidant activity.     

Induction of oxidative stress by organic hydroperoxides in testis and epididymal sperm of rats in vivo

The present study describes the extent and pattern of oxidative stress induction in testis and epididymal sperm of rats following in vivo exposure to repeated sublethal doses of 2 model pro-oxidants, namely, t-butyl hydroperoxide (tbHP) and cumene hydroperoxide (cHP). Single sublethal (1/40, 1/20, and 1/10 LD(50)) doses of hydroperoxides (HP) administered intraperitoneally to male rats (CFT-Wistar strain) failed to induce any significant increase in malondialdehyde or reactive oxygen species (ROS) levels in testis or epididymal sperm. However, repeated doses for 1 or 2 weeks induced a marked dose-related enhancement of lipid peroxidation (LPO) and ROS levels in both testis and epididymal sperm. Further evidence, such as significant perturbations in both enzymic and nonenzymic antioxidants and enhanced levels of protein carbonyls in testis, suggested induction of oxidative stress. In testis, moderate depletion in reduced glutathione levels and marked diminution in ascorbic acid and alpha-tocopherol content were accompanied by increased activities of various antioxidant enzymes, namely glutathione peroxidase, glutathione-S-transferase, and catalase, in both the HP treatments. Furthermore, significant alterations in the specific activities of testicular enzymes such as LDH-X, G-6-PDH, and SDH indicated altered testicular physiology. Both HP at higher doses induced significant DNA damage (determined by fluorimetric analysis of DNA unwinding assay) in testis and epididymal sperm. Increased total iron levels in testis of HP-treated rats are indicative of the possible involvement of iron-mediated free radical reactions in this model. These findings provide an account of early oxidative damage in testis and epididymal sperm following short-term exposure to HP in vivo, and this model is being further exploited for understanding the consequences of chronic oxidative stress-mediated alterations for the physiology of male reproductive system and its implications for fertility.     

Sperm maturation in dogs: sperm profile and enzymatic antioxidant status in ejaculated and epididymal spermatozoa

Spermatozoa become more susceptible to the attack of reactive oxygen species during maturation. To avoid oxidative damage, the epididymis must provide the necessary antioxidant protection. The aim of this study was to compare the canine sperm profile and the enzymatic antioxidant status of the ejaculated fractions and samples collected from the different segments of the epididymis (caput, corpus and cauda). Five adult dogs were used, and after 1–3 weeks, subsequently to bilateral orchiectomy and epididymal storage, sperm samples were collected from the different segments of the epididymis. Samples were evaluated for conventional microscopy and computer‐assisted motility analysis: sperm plasma membrane permeability and the activity of the antioxidant enzymes catalase, glutathione peroxidase (GPx) and superoxide dismutase (SOD). Samples collected from the caput and corpus showed lower values for most of the motility variables evaluated, indicating different levels of immaturity. Catalase activity was observed only in ejaculated samples. Conversely, GPx activity was higher in the cauda epididymidis. Correlations were found between SOD and GPx and SOD and sperm motility in the epididymal cauda and corpus, highlighting the importance of the enzymes for the protection of spermatozoa during the transit along the epididymis.     

Effect of kolaviron,a biflavonoid complex from Garcinia kola seeds,on the antioxidant,hormonal and spermatogenic indices of diabetic male rats

The antihyperglycaemic effect of kolaviron (KV), a biflavonoid from Garcinia kola has been established in previous studies. In this study, we investigated the effect of KV (200 mg kg^?1) on the antioxidant, hormonal and spermatogenic indices of alloxan‐diabetic male rats, and metformin hydrochloride (MET) (30 mg kg^?1) served as standard drug. The results showed that KV and MET significantly (P < 0.05) decreased the fasting blood glucose of the diabetic rats. Also, untreated and MET‐treated diabetic groups had significantly (P < 0.05) lower body‐weight gain and relative weights of testes. In addition, epididymal sperm abnormalities were increased, whereas sperm count, motility, testicular protein and sialic acid were decreased in untreated diabetic group. Also, antioxidant parameters, reduced glutathione, catalase, superoxide dismutase, glutathione‐S‐transferase and glutathione peroxidase were significantly (P < 0.05) reduced in the testes with a concomitant increase in lipid peroxidation in untreated diabetic group. Furthermore, untreated diabetic group had significantly (P < 0.05) lower levels of testosterone, luteinising and follicle‐stimulating hormones relative to controls. Treatment with KV restored the relative weights of testes, activities of antioxidant enzymes, sperm and hormonal indices of the diabetic animals. This study demonstrated the role of KV to promote fertility in diabetic male rats by enhancing the hormonal and antioxidant status of the rats.     

Lipid peroxidation and activity of antioxidant enzymes in muscle of the lower leg before and after arterial reconstruction

Reperfusion syndrome and lipid peroxidation due to toxic effects of free oxygen radicals might be one pathophysiological cause of the oedema that develops during the first week after a femoro-popliteal reconstruction. This paper reports the activity of the protecting antioxidant enzymes superoxide dismutase (SOD), glutathione peroxidase and catalase in gastrocnemic muscle before and after reperfusion of chronically ischaemic legs with comparison to activities in non-ischaemic muscle. Furthermore the susceptibility to lipid peroxidation in the muscle was measured as thiobarbituric acid reactive material (TBAR). The activities of CuZn SOD, Mn SOD and glutathione peroxidase were equal in normally perfused and chronically ischaemic muscle and there was no difference after reperfusion. Muscle catalase activity was low compared to activity of red blood cells and could not be reliably estimated. There was no difference in iron-stimulated lipid peroxidation of ischaemic and non-ischaemic muscle but in reliably estimated. There was no difference in iron-stimulated lipid peroxidation of ischaemic and non-ischaemic muscle but in muscle biopsied 10 min after reperfusion there was a significant increase in production of TBAR indicating an increased susceptibility for lipid peroxidation at this time. The finding is compatible with the occurrence of an oxidant insult on the muscle at reperfusion. Ischaemia--or reperfusion--induced reductions in activity of antioxidant enzymes are however not related to this reaction.     

Time course of antioxidant enzyme activities in liver transplant recipients

Reactive oxygen species (ROS) play a central role in ischemia-reperfusion injury after organ transplantation. They are degraded by endogenous radical scavengers such as antioxidant enzymes. The purpose of this study was to evaluate the temporal variations of antioxidant enzyme activities in liver transplant recipients. The study was performed in 13 liver transplant patients (11 men and 2 women). Blood samples were obtained pre- and postsurgical intervention: before transplant (T(0)), and 1, 6, 12, 24, 48, and 72 hours, as well as 5 and 7 days thereafter. We determined total and specific superoxide dismutase (SOD) activity, catalase (CAT), glutathione peroxidase (GPX), and glutathione reductase (GR) activities as well as malondialdehyde (MDA) and low-density lipoproteins (LDL). The results showed increased SOD and mainly GPX activities after liver transplantation, which correlated with MDA levels. Total SOD activity was mainly represented by Mn-SOD (75%) and Cu,Zn-SOD (25%), whereas Fe-SOD was not detected. In conclusion, the enhanced antioxidant enzyme activities reported in this study indicated a control of oxidative stress generated in liver transplantation. In this sense, although MDA levels showed an enormeous increase at 1 hour after transplantation, the lipid peroxidation was compensated for by GPX activity.     

Protective effects of lupeol and mango extract against androgen induced oxidative stress in Swiss albino mice

Aim： To investigate antioxidant potential of lupeol/mango pulp extract （MPE） in testosterone induced oxidative stress in prostate of male Swiss albino mice. Methods： Oral treatment of lupeol （1 mg/animal） and MPE （1 mL [20% w/v]/ animal） was given separately to animals along with subcutaneous injection of testosterone （5 mg/kg body weight） consecutively for 15 days. At the end of the study period, the prostate was dissected out for the determination of reactive oxygen species （ROS） levels, lipid peroxidation and antioxidant enzymes status （catalase, superoxide dismutase, glutathione reductase, glutathione-S-transferase）. Results： In testosterone treated animals, increased ROS resulted in depletion of antioxidant enzymes and increase in lipid peroxidation in mouse prostate. However, lupeol/MPE treatment resulted in a decrease in ROS levels with restoration in the levels of lipid peroxidation and antioxidant enzymes. Conclusion： The results of the present study demonstrate that lupeol/MPE are effective in combating oxidative stress-induced cellular injury of mouse prostate. Mango and its constituents, therefore, deserve study as a potential chemopreventive agent against prostate cancer. （Asian J Androl 2008 Mar; 10： 313-318）     

Testicular gametogenic and steroidogenic activities in chlorpyrifos insecticide-treated rats: a correlation study with testicular oxidative stress and role of antioxidant enzyme defence systems in Sprague-Dawley rats

The present works examined an adverse effect of chlorpyrifos insecticide on testes and lipid peroxidation at low doses (5 mg-10 mg kg(-1) body weight) and the role of antioxidant enzymes systems at higher doses (20-30 mg kg(-1) body weight) in albino rats. At low doses, reduction in plasma levels of testosterone and FSH and LH hormones along with the significant shrinkage of seminiferous tubules and gametogenic changes in germ cells were noticed. But these changes were restored with the revival of serum testosterone, FSH and LH along with regression of testis at higher doses. Similarly, level of testicular lipid peroxidation was elevated, whereas levels of antioxidant enzymes (superoxide dismutase, catalase and glutathione peroxidase) and steroidogenic enzymes activities (Δ(5) , 3β-hydroxysteroid dehydrogenase and 17β-hydroxysteroid dehydrogenase) were reduced significantly at low doses. But, rat testes showed a significant decrease in lipid peroxidation and concomitant increase in antioxidant enzymes and steroidogenic enzymes activities at higher doses. Results showed that at higher doses of chlorpyrifos treatments, rat testes were shown to trigger their natural defence mechanism which became operative possibly through corrective measure of synthesis of antioxidant defence enzymes and steroidogenic enzymes and pituitary gonadotrophins hormone feedback mechanisms.     

Spontaneous lipid peroxidation and production of hydrogen peroxide and superoxide in human spermatozoa. Superoxide dismutase as major enzyme protectant against oxygen toxicity

Spontaneous lipid peroxidation in washed human spermatozoa was induced by aerobic incubation at 32 C and measured by malonaldehyde production; loss of motility during the incubation was determined simultaneously. Malonaldehyde production at the point of complete loss of motility, defined as the lipoperoxidative lethal endpoint (LLE), was 0.10 +/- 0.03 nmol/10(8) cells (mean +/- SD, n = 40), and was independent of the time to complete loss of motility. Human spermatozoa produced both H2O2 and O2-. during aerobic incubation. Inhibition of superoxide dismutase in these cells with KCN showed that all the H2O2 production is due to action of the dismutase. The superoxide dismutase activity of individual human sperm samples varied between 1 and 10 U/10(8) cells, variations between samples from a single donor being nearly as great as those between different donors. The time to complete motility loss (tL) showed equal variation of 1 to 10 hours among samples. The rate of spontaneous lipid peroxidation, calculated as LLE/tL, for a given sperm sample and the superoxide dismutase activity of the same sample, determined prior to aerobic incubation, gave a good linear correlation (r = 0.97). Glutathione reductase, glutathione peroxidase, and glutathione were found to be present in human spermatozoa, but showed little variation among samples. These results suggest that superoxide dismutase plays the major role in protecting human spermatozoa against lipid peroxidation. In addition, the superoxide dismutase activity of a fresh sperm sample appears to be a good predictor of the lifetime (up to the complete loss of motility) of that particular sample, and so may prove useful in semen analysis.     

Epidural anesthesia may attenuate lipid peroxidation during aorto-femoral surgery

PURPOSE: To determine the effect of epidural anesthesia (EP) on oxygenation of the chronically ischemic limb in patients undergoing aorto-femoral bypass grafting and to assess whether it produces an alteration of lipid peroxidation and antioxidant status following revascularization. METHODS: In this prospective, randomized, single-blinded study 40 ASA II or III patients undergoing elective aorto-femoral bypass grafting were allocated to receive general anesthesia (group GA, n = 20), or epidural + GA (group EP, n = 20) during surgery. Femoral venous blood-gas status, activities of the protecting antioxidant enzymes superoxide dismutase (SOD), glutathione peroxidase (GSH-px), glutathione reductase (GSH-rd), glutathione (GSH) and thiobarbituric acid-reactive substances (TBARS) as a marker of lipid peroxidation were determined in blood samples taken from the femoral vein at different intervals before and after revascularization. RESULTS: Before the induction of anesthesia in group EP, femoral venous PO(2) [mean (standard deviation), 95% confidence interval] increased after achieving an adequate level of blockade by EP extending to the dermatomal level of T6-8 [29.32 (4.6), 26.34-32.30 to 36.29 (4.6), 33.37-39.22 mmHg, P < 0.05]. Femoral venous PO(2) was similar in both groups thereafter. In the GA group a significant increase in erythrocyte TBARS was observed immediately after restoration of blood flow when compared with baseline values [221.32 (102), 148.35-294-29 to 337.26 (123) 248.99-425.53 nmol*g(-1) hemoglobin, P < 0.01] but not at any other moment. In the EP group TBARS did not increase throughout the study. Within group comparisons revealed no significant differences in GSH, GSH-px, GSH-rd and SOD. CONCLUSION: In patients with atherosclerotic aorto-iliac occlusive disease EP may possibly attenuate lipid peroxidation following revascularization but has no effect on antioxidant enzyme activities.     

Effects of gossypol on the antioxidant defense system of the rat testis

This study examined the effects of gossypol acetic acid on the antioxidant defense system of the rat testis. In gossypol-treated animals testis catalase and glutathione peroxidase activities were decreased. Catalase and glutathione peroxidase are the two enzymes that protect against oxidative damage by hydrogen peroxide. Other antioxidants that were reduced in treated animals were glucose-6-phosphate dehydrogenase, superoxide dismutase, glutathione reductase, alpha-tocopherol, and ascorbate. Gossypol, a pigment of cottonseed and cottonseed products, causes infertility in humans and many animal species, but its mechanism of action is unknown. Gossypol is known to produce reactive oxygen species in vitro. Oxidative injury caused by the generation of reactive oxygen species and a compromised antioxidant defense system may be responsible for the antifertility effects of gossypol.     

Effect of lipid peroxidation on beating frequency of human sperm tail

Summary. The tail beat frequency (TBF) of sperm was measured with a sperm-head fixation method which was based on the tendency of sperm to attach its head to the surface of a glass slide. Ferrous sulphate, a promotor of lipid peroxidation, inhibited TBF within 5 min of mixing with sperm. This inhibition can be reversed dose-dependently by superoxide dismutase, catalase, glutathione, and albumin. It was concluded that TBF could be a new pharmacological model for studying the effect of lipid peroxidation and antioxidant on sperm motility. Both enzymatic and non-enzymatic antioxidants can be screened with this method.