Clinical relevance of oxidative stress in male factor infertility: an update

Herbo-mineral supplementation in men with idiopathic oligoasthenoteratospermia : A double blind randomized placebo-controlled trial

Introduction:

There is insufficient scientific data on the medical management options for idiopathic oligoasthenoteratospermia (iOATs). We conducted a double blind, randomized, placebo-controlled trial to assess the efficacy and safety of the herbo-mineral supplement, Addyzoa^®, in infertile men with iOATs. We also evaluated its effect on semen reactive oxygen species (ROS) levels, total antioxidant capacity (TAC) and DNA fragmentation index.

Materials and Methods:

Fifty infertile men with iOATS were recruited into an institutional ethics committee approved protocol from April to August 2009. Randomization was done using numbered, identical containers. Baseline semen samples were evaluated for routine parameters, ROS level, DNA fragmentation index and TAC. Drug/placebo was administered at a dose of two capsules twice a day for 3 months. All parameters were reassessed at 3 months and clinical side-effects were recorded. The study was registered with the Clinical Trials Registry of India and is available at www.ctri.in as study protocol number CTRI/2009/091/000551.

Results:

Forty-four subjects completed the study, 21 in the drug arm and 23 in the placebo arm. There was no difference in baseline parameters between the two groups. Men in the drug group had significant improvement in mean total motility from 23.2 ± 17.3% to 33.4 ± 23.2% (P-value: 0.008) and mean progressive (Type A+B) motility from 15.7 ± 12.6% to 22.6 ± 18.0% (P-value: 0.024). ROS, TAC and DFI did not change significantly in either group and did not show any correlation with other semen parameters.

Conclusions:

Treatment with Addyzoa resulted in a significant improvement in total and progressive motility in the semen of men with iOATs after 3 months of therapy. There was no change in the sperm concentration, ROS, DFI or TAC levels.

Effects of highly purified follicle-stimulating hormone on sperm DNA damage in men with male idiopathic subfertility: a pilot study

BACKGROUND

Gonadotropins administration have been demonstrated effective for the treatment of idiopathic male infertility, even if no clear data regarding their specific mechanism of action on semen quality are at the moment available.

AIM

To evaluate the effect of highly purified FSH (hpFSH) administration on standard semen parameters, sperm oxidative stress, and sperm chromatin structure and DNA fragmentation.

MATERIAL AND METHODS

In the current prospective baseline-controlled study, 36 subjects with male idiophatic infertility were enrolled. Baseline clinical and biochemical data were evaluated. Before and after 3 months of treatment with hpFSH, sperm samples were collected and standard semen analysis, reactive oxygen species (ROS) assessment and sperm DNA fragmentation were evaluated.

RESULTS

A significant (p<0.05) improvement from baseline in standard seminal parameters was observed. A significant (p<0.05) reduction in sperm ROS levels and DNA fragmentation was observed. Statistically significant (p<0.05) correlations between variation in ROS levels and both seminal parameters and DNA fragmentation variations were detected.

CONCLUSIONS

Three months of hpFSH administration seems to reduce ROS and DNA damage in subjects with male idiopathic subfertility improving semen parameters. Further evidences from well-designed randomized double-blind placebo- controlled studies are needed in order to confirm our preliminary results.

Chemoprotection of ethylene glycol monoethyl ether-induced reproductive toxicity in male rats by kolaviron, isolated biflavonoid from Garcinia kola seed

The present study investigated the protective effect of kolaviron, a biflavonoid from the seed of Garcinia kola, on ethylene glycol monoethyl ether (EGEE)-induced reproductive toxicity in male rats. The protective effect of kolaviron was validated using vitamin E, a standard antioxidant. EGEE was administered at a dose of 200 mg/kg. Other groups of rats were simultaneously treated with kolaviron (100 and 200 mg/kg) and vitamin E (50 mg/kg) for 14 days. EGEE treatment resulted in significant decrease in glutathione (GSH) level, superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) activities but markedly increased the glutathione-S-transferase (GST) and lactate dehydrogenase (LDH) activities in the testes. In the spermatozoa, administration of EGEE caused significant decrease in the activities of CAT, GPx, GST and LDH as well as in the level of GSH but significantly increased SOD activity with concomitant increase in hydrogen peroxide and malondialdehyde levels in both testes and spermatozoa. EGEE-exposed rats showed marked testicular degeneration with concomitant decrease in spermatozoa quantity and quality. Overall, EGEE causes reproductive dysfunction in rats by altering antioxidant systems in the testes and spermatozoa. Kolaviron or vitamin E exhibited protective effects against EGEE-induced male reproductive toxicity by enhancement of antioxidant status and improvement in spermatozoa quantity and quality.

Group X secreted phospholipase A₂ specifically decreases sperm motility in mice

Different mammalian secreted phospholipases A(2) (sPLA(2) s) are expressed in male reproductive organs and/or in sperm cells but their cellular functions are still not fully characterized. Because several reports indicate a link between cellular lipids and sperm motility, we have investigated the effect of mouse group IIA, IID, IIE, V, and X sPLA(2) s on sperm motility. Among these enzymes, only mouse group X sPLA(2) (mGX sPLA(2) ) acts as a potent inhibitor of sperm motility that decreases track speed (VCL) and lateral displacement of the head (ALH) of both noncapacitated and capacitated sperm. The inhibitory effect of mGX sPLA(2) is dependent on its enzymatic activity because (i) both the proenzyme form of mGX sPLA(2) (pro-mGX) and the H48Q mutant of mGX sPLA(2) have very weak enzymatic activity and are unable to modulate sperm motility and (ii) LY329722, a specific inhibitor of sPLA(2) s, blocks the inhibitory effect of mGX sPLA(2) . Moreover, mGX sPLA(2) exerts a gradual potency on sperm subpopulations with different velocities, an effect which may be linked to the heterogeneity of lipid composition in these sperm subpopulations. Finally, we found that endogenous mGX sPLA(2) released during spontaneous acrosome reaction modulates sperm motility of capacitated sperm. Together, our results suggest a new role of sPLA(2) in sperm physiology where the sPLA2 selects a sperm subpopulation for fertilization based on its effect on sperm motility.

Coenzyme Q(10) in male infertility: physiopathology and therapy

Both the bioenergetic and the antioxidant role of CoQ(10) suggest a possible involvement in sperm biochemistry and male infertility. CoQ(10) can be quantified in seminal fluid, where its concentration correlates with sperm count and motility. It was found that distribution of CoQ(10) between sperm cells and seminal plasma was altered in varicocele patients, who also presented a higher level of oxidative stress and lower total antioxidant capacity. The effect of vericocelectomy on partially reversing these biochemical abnormalities is discussed. The redox status of coenzyme Q(10) in seminal fluid was also determined: an inverse correlation was found between ubiquinol/ubiquinone ratio and hydroperoxide levels and between this ratio and the percentage of abnormal sperm forms. After the first in vitro observations CoQ(10) was administered to infertile patients affected by idiopathic asthenozoospermia, originally in an open label study and then in three randomized placebo-controlled trials; doses were around 200-300 mg/day and treatment lasted 6 months. A significant increase in the concentration of CoQ(10) was found, both in seminal plasma and sperm cells. Treatment also led to a certain improvement in sperm motility. In one of the studies there was also a decrease in plasma levels of follicle stimulating horhone (FSH) and luteinizine horhone (LH). Administration of CoQ(10) may play a positive role in the treatment of asthenozoospermia, possibly related to not only to its function in the mitochondrial respiratory chain but also to its antioxidant properties. Further studies are needed in order to determine whether there is also an effect on fertility rate.

Coenzyme Q10 improves seminal oxidative defense but does not affect on semen parameters in idiopathic oligoasthenoteratozoospermia: a randomized double-blind, placebo controlled trial

BACKGROUND

Several lines of evidence show the implication of oxidative stress in the etiology of male infertility. Recently, the role of coenzyme Q10 (CoQ10) in the prevention and treatment of disease has been intensively probed. However, definitive efficacy studies in oligoasthenoteratozoospermia (OAT) have not been completed yet.

AIM

To evaluate the effect of CoQ10 supplementation on semen parameters in idiopathic OAT (iOAT).

MATERIAL/SUBJECTS AND METHODS

A double-blind placebo controlled clinical trial was carried out. A total of 47 infertile men with iOAT were randomly assigned to receive 200 mg CoQ10 daily or placebo during a 12- week period. Semen parameters were determined using microscopic evaluation according to World Health Organization guidelines. Lipid peroxidation was assessed by measuring the concentration of plasma malondialdehyde. We evaluated the total antioxidant capacity of seminal plasma. To compare variables between and within the 2 groups we used independent t-test and Paired t-test.

RESULTS

The trial showed non-significant changes in semen parameters of CoQ10 group. However, concentrations of thiobarbituric acid-reactive substances were significantly (p<0.05) reduced in serum of treated groups compared with the control. Furthermore, total antioxidant capacity of seminal plasma significantly increased in the CoQ10 group (p<0.05).

CONCLUSION

Our results provide further evidence suggesting that CoQ10 supplementation is associated with alleviating oxidative stress, although it does not show any significant effects on sperm concentration, motility and morphology. It may be suggested that CoQ10 could be taken as an adjunct therapy in cases of OAT. Further studies are needed to draw a final conclusion.

Semen analysis and sperm function tests: How much to test?

Semen analysis as an integral part of infertility investigations is taken as a surrogate measure for male fecundity in clinical andrology, male fertility, and pregnancy risk assessments. Clearly, laboratory seminology is still very much in its infancy. In as much as the creation of a conventional semen profile will always represent the foundations of male fertility evaluation, the 5th edition of the World Health Organization (WHO) manual is a definitive statement on how such assessments should be carried out and how the quality should be controlled. A major advance in this new edition of the WHO manual, resolving the most salient critique of previous editions, is the development of the first well-defined reference ranges for semen analysis based on the analysis of over 1900 recent fathers. The methodology used in the assessment of the usual variables in semen analysis is described, as are many of the less common, but very valuable, sperm function tests. Sperm function testing is used to determine if the sperm have the biologic capacity to perform the tasks necessary to reach and fertilize ova and ultimately result in live births. A variety of tests are available to evaluate different aspects of these functions. To accurately use these functional assays, the clinician must understand what the tests measure, what the indications are for the assays, and how to interpret the results to direct further testing or patient management.

Effect of spermatic vein ligation on seminal total antioxidant capacity in terms of varicocele grading

We aimed to assess the effect of spermatic vein ligation on seminal total antioxidant capacity (TAC) in patients with varicocele. Twenty infertile male patients with varicocele and 20 normal fertile men (control group) were included in the study. All the male patients were diagnosed with primary infertility and varicocele. The patients with varicocele were divided into two groups as nonpalpable (GI) (eight patients) and palpable (GII-III) (12 patients) varicocele groups. All the patients underwent microsurgical spermatic vein ligation. Seminal TAC levels and sperm parameters were evaluated in all the patients. Preoperative sperm count, sperm motility, sperm morphology and seminal TAC levels with equivalent figures 3-6 months after spermatic vein ligation and the same values of the control group were compared. There was a statistically significant increase in the total seminal antioxidant capacity level after spermatic vein ligation, and there was a statistically significant increase in the sperm count, sperm motility and spermatozoa with normal morphology. However, evaluation of the patients for varicocele grade showed a statistically significant increase in the TAC level only in the GII-III varicocele group. Spermatic vein ligation can improve the total seminal antioxidant capacity levels especially in patients with middle and high grade varicocele.

Study of GT-repeat expansion in Heme oxygenase-1 gene promoter as genetic cause of male infertility

PURPOSE

The length of GT-repeats polymorphic region in the promoter of human Heme oxygenase-1 gene (HO-1) alters the level of its transcriptional activity in response to oxidative stresses. Decreased level of HO-1 protein in the seminal plasma has been reported to be associated with oligospermia and azoospermia in male infertility. This is the first study to investigate the association between GT-repeats expansion in the promoter of the HO-1 gene and male infertility.

METHODS

The frequencies of different GT-repeats alleles in the promoter of HO-1 gene were determined in 100 cases and 100 normal controls using PCR-PAGE, ABI fragment analysis genotyping and sequencing analysis.

RESULTS

All alleles were classified into S and L alleles. S alleles were specified as number 0 to 3 with <27 GT-repeats and L alleles were specified as number 4 to 6 with >27 repeats. The L allele frequency was significantly higher among case group (54.5%) than that was obtained in the normal control group (37.5%). Statistical analysis provided a significant relationship between L allele and male infertility (P < 0.001).

CONCLUSIONS

This study shows for the first time that GT-repeats expansion in promoter of the HO-1 gene is associated with oligospermia and azoospermia among Iranian infertile cases.

Study of GT-repeat expansion in Heme oxygenase-1 gene promoter as genetic cause of male infertility

PURPOSE

The length of GT-repeats polymorphic region in the promoter of human Heme oxygenase-1 gene (HO-1) alters the level of its transcriptional activity in response to oxidative stresses. Decreased level of HO-1 protein in the seminal plasma has been reported to be associated with oligospermia and azoospermia in male infertility. This is the first study to investigate the association between GT-repeats expansion in the promoter of the HO-1 gene and male infertility.

METHODS

The frequencies of different GT-repeats alleles in the promoter of HO-1 gene were determined in 100 cases and 100 normal controls using PCR-PAGE, ABI fragment analysis genotyping and sequencing analysis.

RESULTS

All alleles were classified into S and L alleles. S alleles were specified as number 0 to 3 with <27 GT-repeats and L alleles were specified as number 4 to 6 with >27 repeats. The L allele frequency was significantly higher among case group (54.5%) than that was obtained in the normal control group (37.5%). Statistical analysis provided a significant relationship between L allele and male infertility (P < 0.001).

CONCLUSIONS

This study shows for the first time that GT-repeats expansion in promoter of the HO-1 gene is associated with oligospermia and azoospermia among Iranian infertile cases.

Redox regulation of fertilisation and the spermatogenic process

Oxidative stress is one of the major causes of male infertility; it damages spermatogenic cells, the spermatogenic process and sperm function. Recent advances in redox biology have revealed the signalling role of reactive oxygen species (ROS) that are generated by cells. While highly reactive oxidants, such as the hydroxyl radical, exert largely deleterious effects, hydrogen peroxide can feasibly serve as a signal mediator because it is moderately reactive and membrane permeable and because it can oxidize only limited numbers of functional groups of biological molecules. The amino acid side chain most sensitive to oxidation is cysteine sulphydryl, which is commonly involved in the catalysis of some enzymes. Although the reactivity of cysteine sulphhydryl is not very high in ordinary proteins, some phosphatases possess a highly reactive sulphydryl group at their catalytic centre and are thereby oxidatively inactivated by transiently elevated hydrogen peroxide levels after extracellular stimuli and under certain environmental conditions. Peroxiredoxins, in turn, show moderate hydrogen peroxide-reducing activity, and their role in the modulation of ROS-mediated signal transduction in ordinary cells, mediated by protecting phosphatases from oxidative inactivation, has attracted much attention. Although knowledge of the signalling role of ROS in the male reproductive system is limited at present, its significance is becoming a focal issue. Here, we present a review of the emerging signalling role of hydrogen peroxide in testes.

Urinary trichloroacetic acid levels and semen quality: a hospital-based cross-sectional study in Wuhan, China

Toxicological studies indicate an association between exposure to disinfection by-products (DBPs) and impaired male reproductive health in animals. However, epidemiological evidence in humans is still limited. We conducted a hospital-based cross-sectional study to investigate the effect of exposure to DBPs on semen quality in humans. Between May 2008 and July 2008, we recruited 418 male partners in sub-fertile couples seeking infertility medical instruction or assisted reproduction services from the Tongji Hospital in Wuhan, China. Major semen parameters analyzed included sperm concentration, motility, and morphology. Exposure to DBPs was estimated by their urinary creatinine-adjusted trichloroacetic (TCAA) concentrations that were measured with the gas chromatography/electron capture detection method. We used linear regression to assess the relationship between exposure to DBPs and semen quality. According to the World Health Organization criteria (<20 million/mL for sperm concentration and <50% motile for sperm motility) and threshold value recommended by Guzick (<9% for sperm morphology), there were 265 men with all parameters at or above the reference values, 33 men below the reference sperm concentration, 151 men below the reference sperm motility, and 6 men below the reference sperm morphology. The mean (median) urinary creatinine-adjusted TCAA concentration was 9.2 (5.1) μg/g creatinine. Linear regression analyses indicated no significant association of sperm concentration, sperm count, and sperm morphology with urinary TCAA levels. Compared with those in the lowest quartile of creatinine-adjusted urinary TCAA concentrations, subjects in the second and third quartiles had a decrease of 5.1% (95% CI: 0.6%, 9.7%) and 4.7% (95% CI: 0.2%, 9.2%) in percent motility, respectively. However, these associations were not significant after adjustment for age, abstinence time, and smoking status. The present study provides suggestive but inconclusive evidence of the relationship between decreased sperm motility and increased urinary TCAA levels. The effect of exposure to DBPs on human male reproductive health in Chinese populations still warrants further investigations.

Bacteria in bovine semen can increase sperm DNA fragmentation rates: a kinetic experimental approach

Cryopreserved straws of semen (n=228) from Holstein bulls (n=47) were examined for bacterial presence and sperm DNA fragmentation (SDF) dynamics. Commercial semen doses (representing six ejaculates per individual) were randomly selected from a bull stud in Spain. The dynamics of SDF were assessed after thawing (T0) and at 4, 24, 48, 72 and 96h of incubation at 37°C, using the commercial variant of the sperm chromatin dispersion test for Bovine (Halomax®). One group of bulls showed a bacterial presence in semen samples between 0 and 96h of incubation (n=23, group A) while the other did not (n=24, group B). Immediate post-thaw differences in SDF were not observed when both groups were compared. However, the rate of increase in SDF (rSDF) over time, considered as an estimate of the kinetic behaviour of sperm DNA survival, was significantly higher (P<0.05) in semen samples from group A (0.7% per hour) versus group B (0.05% per hour). Polymerase Chain Reaction (PCR) assay was used for DNA amplification using primers designed for specific regions of the bacterial gene that codifies for 16S rRNA. Different species within the phyla Bacteroidetes, Firmicutes, Proteobacteria, Cyanobacteria, Fusobacteria and Actinobacteria were identified. The results show that (1) SDF at baseline (T0) may not be affected by the presence of bacteria but the rSDF can increase due to bacterial growth during incubation, (2) the increase in the rSDF is characteristic of some bulls but not for others, and (3) certain bacterial strains are repeatedly found in separate ejaculates from the same bull.

Impacts of oxidative stress and antioxidants on semen functions

Oxidative stress (OS) has been considered a major contributory factor to the infertility. Oxidative stress is the result of imbalance between the reactive oxygen species (ROS) and antioxidants in the body which can lead to sperm damage, deformity, and eventually male infertility. Although high concentrations of the ROS cause sperm pathology (ATP depletion) leading to insufficient axonemal phosphorylation, lipid peroxidation, and loss of motility and viability but, many evidences demonstrate that low and controlled concentrations of these ROS play an important role in sperm physiological processes such as capacitation, acrosome reaction, and signaling processes to ensure fertilization. The supplementation of a cryopreservation extender with antioxidant has been shown to provide a cryoprotective effect on mammalian sperm quality. This paper reviews the impacts of oxidative stress and reactive oxygen species on spermatozoa functions, causes of ROS generation, and antioxidative strategies to reduce OS. In addition, we also highlight the emerging concept of utilizing OS as a tool of contraception.

Toxic effect of cyclophosphamide on sperm morphology, testicular histology and blood oxidant-antioxidant balance, and protective roles of lycopene and ellagic acid

In this study, the toxic effect of cyclophosphamide (CP) on sperm morphology, testicular histology and blood oxidant-antioxidant balance, and protective roles of lycopene (LC) and ellagic acid (EA) were investigated. For this purpose, 48 healthy, adult, male Sprague-Dawley rats were divided into six groups; eight animals in each group. The control group was treated with placebo. LC, EA and CP groups were given alone LC (10 mg/kg/every other day), EA (2 mg/kg/every other day) and CP (15 mg/kg/week) respectively. One of the last two groups received CP + LC, and the other treated with CP + EA. All treatments were maintained for 8 weeks. At the end of the treatment period, morphological abnormalities of sperm, plasma malondialdehyde (MDA) levels and glutathione (GSH) levels, and GSH-peroxidase (GSH-Px), catalase (CAT) and superoxide dismutase (SOD) activities in erythrocytes, and testicular histopathological changes were examined. CP administration caused statistically significant increases in tail and total abnormality of sperm, plasma MDA level and erythrocyte SOD activity, and decreases in erythrocyte CAT activity, diameters of seminiferous tubules, germinal cell layer thickness and Johnsen's Testicular Score along with degeneration, necrosis, immature germ cells, congestion and atrophy in testicular tissue. However, LC or EA treatments to CP-treated rats markedly improved the CP-induced lipid peroxidation, and normalized sperm morphology and testicular histopathology. In conclusion, CP-induced lipid peroxidation leads to the structural damages in spermatozoa and testicular tissue of rats, and also LC or EA have a protective effect on these types of damage.

Effect of ultraviolet C irradiation on human sperm motility and lipid peroxidation

PURPOSE

Ultraviolet C (UVC) irradiation of aqueous solutions is known to be a good source of reactive oxygen species (ROS). The aim of this study is to examine the effect of increasing doses of UVC irradiation, in the presence and absence of the antioxidant butylated hydroxytoluene (BHT), on human sperm motility and lipid peroxidation of its membranes.

MATERIALS AND METHODS

Human sperm samples were irradiated with UVC light (254 nm) for different periods of time. A computer-assisted semen analysis of sperm motility was carried out after UV irradiation. The percentage of motile sperm (%MOT), progressive motility, straight line velocity (VSL), curvilinear velocity (VCL) and the percentage of linearity (%LIN) were evaluated. The level of lipid peroxidation of sperm membranes was estimated by measurement of the thiobarbituric acid reactive substances (TBARS).

RESULTS

UVC irradiation of human spermatozoa produced a diminution of the sperm motility (%MOT, progressive motility, VSL, VCL, %LIN), viability and, concomitantly, an increase of the level of lipid peroxidation of the sperm membranes. The observed effects of the UVC irradiation were prevented by addition of the antioxidant BHT, indicating that the effects of UVC on the tested sperm parameters are mediated by an important rise in lipid peroxidation of the sperm membrane.

CONCLUSION

Lipid peroxidation of the human sperm plasma membrane leads to a decrease in the sperm motility (%MOT, progressive motility, VSL, VCL, %LIN) and viability. The protective effect of BHT on the UVC-irradiated sperm cells indicates the effects of ROS on sperm function.

Preliminary examination of polymorphisms of GSTM1, GSTT1, and GSTZ1 in relation to semen quality

BACKGROUND

Environmental, lifestyle, and occupational exposures on semen quality have been investigated in epidemiological studies with inconsistent results. Genetic factors involved in toxicant activation and detoxification have been examined in relation to the risk of outcomes such as cancer, cardiovascular, and neurologic disorders. However, the effect of common genetic variants in the metabolism of toxicants on semen quality parameters has rarely been evaluated. In this analysis, we evaluated functional SNPs of three genes of the glutathione-S-transferase (GSTM1, GSTT1, GSTZ1) enzyme family.

METHODS

Participants were 228 presumed fertile men recruited as part of a community-based study. Semen outcome data from this study included total sperm count and concentration, sperm morphology, and sperm DNA integrity and chromatin maturity. DNA was obtained from 162 men from a mouth-rinse sample and genotyped for the presence of GSTT1-1 and GSTM1-1 null genotypes and the GSTZ1 SNPs at positions 94 (rs3177427) and 124 (rs3177429). We used multivariable linear regression to assess the relationship between each genotype and sperm outcomes.

RESULTS

Overall, our results did not reveal a consistent pattern between GSTM1 and GSTZ genotypes and increased occurrence of adverse sperm outcomes. However, the GSTT1 non-null genotype yielded the coefficients with the largest magnitude for sperm count and sperm concentration (beta=-0.528, 95% CI -1.238 to 0.199 and beta=-0.353, 95% CI -0.708 to 0.001, respectively), suggesting that it might be adverse.

CONCLUSIONS

These results indicate that common polymorphisms in GST genes do not negatively impact sperm parameters in healthy men with good semen quality. Contrary to expectations, the GSTT1 non-null genotype was associated with reduced sperm concentration and count in semen. Further study with a larger study size and inclusion of gene-exposure interactions is warranted.

Reactive oxygen species levels are independent of sperm concentration, motility, and abstinence in a normal, healthy, proven fertile man: a longitudinal study

In a longitudinal study over a period of 21 months, we demonstrated that seminal reactive oxygen species (ROS) levels are independent of sperm concentration, motility, and abstinence duration within a healthy sperm donor, although some variations were observed in ROS levels. We suggest that fluctuation in seminal ROS values may be related to physiologic or transient changes in spermatogenesis.

Bacterial lipopolysaccharide-induced oxidative stress in adult rat Sertoli cells in vitro

Inflammatory reactions that result from microbial infections, both localized and systemic, are reported to cause transient or permanent male infertility. The cellular mechanisms underlying the inhibitory effect of microbial infection on spermatogenesis is not fully understood. However, there is evidence that spermatogenesis is affected by bacterial lipopolysaccharides (LPS) that induce acute inflammatory responses. The aim here was to use LPS treatments to investigate the potential oxidative stress and toxicity in primary cultures of adult rat Sertoli cells. The Sertoli cells were established and incubated with different concentrations of LPS (5, 10 or 20 microg/ml) for 6, 12 and 24h. Lipid peroxidation (LPO) and hydrogen peroxide (H(2)O(2)) production, along with superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione-S-transferase (GST), glutathione reductase (GR), reduced glutathione (GSH), lactate, lactic acid dehydrogenase (LDH), gamma-glutamyl transpeptidase (gamma-GT) and beta-glucuronidase were measured in these cells. LPO as well as H(2)O(2) production were significantly increased while antioxidant enzyme activities and GSH concentration were significantly depressed. Effects were dose and time-dependent at all incubation periods with 10 and 20 microg/ml LPS. Moreover, markers of Sertoli cell function such as lactate production, LDH, gamma-GT and beta-glucuronidase activities were decreased in a time and dose-dependent manner. Incubation of Sertoli cells with 5 microg/ml LPS for 12 and 24h significantly increased oxidative status but significantly decreased the antioxidant enzyme activities, GSH concentration and Sertoli cell markers. In contrast, the oxidative and antioxidant status and markers of Sertoli cell function did not show any significant change in treated Sertoli cells with 5 microg/ml LPS for 6h. Therefore, it may be concluded that LPS induces oxidative stress in Sertoli cells and adversely affects Sertoli cell functions.

Antiperoxidative and anti-apoptotic effects of lycopene and ellagic acid on cyclophosphamide-induced testicular lipid peroxidation and apoptosis

The present study was conducted to investigate the possible protective effects of lycopene (LC) and ellagic acid (EA) on cyclophosphamide (CP)-induced testicular and spermatozoal toxicity associated with the oxidative stress and apoptosis in male rats. Forty-eight healthy adult male Sprague-Dawley rats were divided into six groups of eight rats each. The control group was treated with placebo; the LC, EA and CP groups were given LC (10 mg kg–1), EA (2 mg kg–1) and CP (15 mg kg–1), respectively, alone; the CP+LC group was treated with a combination of CP (15 mg kg–1) and LC (10 mg kg–1); and the CP+EA group was treated with a combination of CP (15 mg kg–1) and EA (2 mg kg–1). All treatments were maintained for 8 weeks. At the end of the treatment period, bodyweight and the weight of the reproductive organs, sperm concentration and motility, testicular tissue lipid peroxidation, anti-oxidant enzyme activity and apoptosis (i.e. Bax and Bcl-2 proteins) were determined. Administration of CP resulted in significant decreases in epididymal sperm concentration and motility and significant increases in malondialdehyde levels. Although CP significantly increased the number of Bax-positive (apoptotic) cells, it had no effect on the number of Bcl-2-positive (anti-apoptotic) cells compared with the control group. However, combined treatment of rats with LC or EA in addition to CP prevented the development of CP-induced lipid peroxidation and sperm and testicular damage. In conclusion, CP-induced lipid peroxidation leads to structural and functional damage, as well as apoptosis, in spermatogenic cells of rats. Both LC and EA protect against the development of these detrimental effects.

Attenuation of cyclosporine A-induced testicular and spermatozoal damages associated with oxidative stress by ellagic acid

This study was conducted to investigate the possible protective effect of ellagic acid (EA) on cyclosporine A (CsA)-induced testicular and spermatozoal damages associated with oxidative stress in male rats. Forty adult male Sprague-Dawley rats were divided into 4 groups of 10 animals each. Control group was used as placebo. Cyclosporine group received CsA at the dose of 15 mg/kg/day. Ellagic acid group was treated with EA (10 mg/kg/day). Cyclosporine plus ellagic acid group received CsA+EA. Reproductive organs were weighed and epididymal sperm characteristics and histopathological structure of testes were examined along with malondialdehyde (MDA) and glutathione (GSH) levels, glutathione-peroxidase (GSH-Px) and catalase (CAT) activities in testicular tissue. CsA significantly decreased the weights of testes and ventral prostate, epididymal sperm concentration, motility, testicular tissue glutathione (GSH), glutathione-peroxidase (GSH-Px) and catalase (CAT), diameters of seminiferous tubules and germinal cell layer thickness, and it significantly increased malondialdehyde (MDA) level and abnormal sperm rates along with degeneration, necrosis, immature germ cells, congestion and atrophy in testicular tissue. However, the CsA plus EA treatment attenuated all the CsA-induced negative changes observed in the testicular tissue, sperm and oxidant/antioxidant parameters. In conclusion, CsA-induced oxidative stress leads to the structural and functional damages in the testicular tissue and sperm quality of rats, and also EA has a protective effect on these damages.

Sperm characteristics and ultrastructure of testes of rats after long-term treatment with the methanol subfraction of Carica papaya seeds

The contraceptive efficacy of Carica papaya seeds after short-term evaluation has been well established. We have examined the safety and mechanism of contraception in rats after long-term treatment with the methanol subfraction (MSF) of C. papaya seeds. The test substance was administered orally to the male albino rats (n = 40) at 50 mg per kg body weight each day for 360 days. Control animals (n = 40) received olive oil as a vehicle. Recovery was assessed up to 120 days after treatment withdrawal. Sperm parameters, serum testosterone levels, fertility, histology and ultrastructure of the testis, haematology and serum clinical chemistry were evaluated to establish the safety and efficacy of the test substance. Safety of long-term treatment was evidenced by unaltered health status, organ weight, haematology and clinical chemistry, and by an increase in body weight. The mechanism of contraception was shown by reduction in nuclear and cytoplasmic volume, normal nuclear characteristics and vacuolization in the cytoplasmic organelles of the Sertoli cells, as well as nuclear degeneration in spermatocytes and spermatids indicating disturbed spermatogenesis. Leydig cells were normal. Initial effects were observed in Sertoli cells at 60 days of treatment. Spermatocytes and spermatids were affected after 120-240 days of treatment. A significant decline in sperm count and viability, total inhibition of sperm motility, increased numbers of sperm abnormalities, normal serum testosterone levels and 100% sterility were evident after 60 days of treatment. All the altered parameters, including percent fertility, were restored to control level 120 days after treatment withdrawal. It is concluded that the MSF is safe for long-term treatment and the mechanism of contraception is shown by its effect on spermatid differentiation in the testis, possibly mediated by the Sertoli cell factors.

Modulatory role of lipoic acid on lipopolysaccharide-induced oxidative stress in adult rat Sertoli cells in vitro

Inflammatory reactions to microbial infections may cause male infertility. The mechanisms of inhibition of spermatogenesis can be studied in vitro using rat Sertoli cells. Bacterial lipopolysaccharides (LPS) induce acute inflammations. So LPS treated Sertoli cells can be used to test for new therapeutic compounds. The present study aimed to investigate the protective efficacy of dl-alpha-lipoic acid (LA) on lipopolysaccharide (LPS)-induced oxidative stress in adult rat Sertoli cells. Sertoli cells were divided into 4 groups. Group I served as a control incubated with water (vehicle). Groups II and IV were incubated with 100 microM LA for 24h before incubating Groups III and IV with 50 microg/ml lipopolysaccharide (LPS) for 12h. In Group III cells (LPS-treated, no LA) the lactate concentration was decreased whereas hydrogen peroxide production and lipid peroxidation were significantly increased. Moreover, the activities of antioxidant enzymes such as superoxide dismutase, glutathione peroxidase, catalase, glutathione-S-transferase, glutathione reductase were reduced. The concentrations of antioxidant molecules such as reduced glutathione and vitamin C were significantly decreased. The activities of enzymes normally elevated in Sertoli cells, gamma-glutamyl transpeptidase and beta-glucuronidase, were significantly decreased. Treatment with LA (100 microM) for 24h before LPS-treatment (Group IV), prevented these changes in enzyme activities and metabolite concentrations. Therefore, LA may have a cyto-protective role during LPS-induced inflammation in adult rat Sertoli cells.