The association of folate, zinc and antioxidant intake with sperm aneuploidy in healthy non-smoking men

Elemental composition of human semen is associated with motility and genomic sperm defects among older men

BACKGROUND

Older men tend to have poorer semen quality and are generally at higher risks for infertility and abnormal reproductive outcomes.

METHODS

We employed proton-induced X-ray emission (PIXE, 3 MeV proton beam) to investigate the concentrations of zinc, copper, calcium, sulfur, chlorine, potassium, titanium, iron and nickel in washed sperm and seminal plasma from non-smoking groups of 10 older men (65-80 years old) and 10 younger men (22-28 years old) who were concurrently assayed for sperm function and genomicly defective sperm.

RESULTS

The older group showed elevated zinc, copper and calcium in sperm and elevated sulfur in seminal plasma compared with the younger men. The older group also showed reduced motility as well as increased sperm DNA fragmentation, achondroplasia mutations, DNA strand breaks and chromosomal aberrations. Sperm calcium and copper were positively associated with sperm DNA fragmentation (P < 0.03). Seminal sulfur was positively associated with sperm DNA fragmentation and chromosomal aberrations (P < 0.04), and negatively associated with sperm motility (P < 0.05). Sperm calcium was negatively associated with sperm motility, independent of male age (P = 0.01).

CONCLUSIONS

We identified major differences in elemental concentrations between sperm and seminal plasma and that higher sperm copper, sulfur and calcium are quantitatively associated with poorer semen quality and increased frequencies of genomic sperm defects.

Intake of food groups and idiopathic asthenozoospermia: a case-control study

STUDY QUESTION

Is there any association between the intake of different food groups and the risk of idiopathic asthenozoospermia?

SUMMARY ANSWER

A high intake of processed meat and sweets was positively associated with a higher risk of asthenozoospermia, whereas a high intake of fruits, vegetables, poultry, skim milk and sea foods was associated with a lower risk.

WHAT IS KNOWN ALREADY

A high intake of lipophilic foods like meat products or milk may be negatively associated with semen quality in humans, whereas some fruits or vegetables may maintain or improve semen quality.

STUDY DESIGN, SIZE, DURATION

A case-control study including 72 asthenozoospermic men and 169 normozoospermic men all from infertile couples who underwent face-to-face private interviews, from January 2011 to December 2011.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Semen was assessed by volume, sperm concentration, motility and morphology. Usual dietary intakes were assessed using a semi-quantitative food frequency questionnaire. Odds ratios (ORs), 95% confidence intervals (CIs) and evaluation of trends were calculated using logistic regression. The first tertile served as the reference category for regression analyses.

MAIN RESULTS AND THE ROLE OF CHANCE

After adjusting for potential confounders, the risk of asthenozoospermia was significantly higher in the highest tertiles of processed meat (OR: 2.03, 95% CI: 1.70-2.44) and sweets intake (OR: 2.05, 95% CI: 1.09-2.26). Conversely, being in the highest tertile of total fruits and vegetables, the intake of dark green vegetables, skim milk, poultry and sea food intake was associated with a lower risk of asthenozoospermia (P for trend = 0.04, 0.01, 0.02, 0.03 and 0.04, respectively).

LIMITATIONS, REASONS FOR CAUTION

Recall bias, selection bias and measurement bias are inevitable in this kind of study and residual confounding due to omission or imprecise measurement of important covariates remains possible.

WIDER IMPLICATIONS OF THE FINDINGS

Patients with asthenozoospermia should be advised to adhere to a diet rich in fruits, vegetables, poultry, skim milk and sea foods while low in processed meat and sweets.

STUDY FUNDING/COMPETING INTEREST(S)

This study was financially supported by the National Nutrition and Food Technology Research Institute, Faculty of Nutrition and Food Technology, Shahid Beheshti University of Medical Science, Tehran, Iran. No conflict of interests to declare.

Micronutrients intake is associated with improved sperm DNA quality in older men

OBJECTIVE

To investigate whether lifestyle factors such as increased dietary intake of micronutrients reduce the risks of sperm DNA damage, and whether older men benefit more than younger men.

DESIGN

Cross-sectional study design with equalized assignments into age groups.

SETTING

National laboratory and university.

PATIENT(S)

Nonclinical group of 22-80-year-old nonsmoking men (n = 80) who reported no fertility problems.

MAIN OUTCOME MEASURE(S)

Sperm DNA damage measured by alkaline and neutral DNA electrophoresis (i.e., sperm Comet assay).

RESULT(S)

Sociodemographics, occupational exposures, medical and reproductive histories, and lifestyle habits were determined by questionnaire. The average daily dietary and supplement intake of micronutrients (vitamin C, vitamin E, b-carotene, zinc, and folate) was determined using the 100-item Modified Block Food Frequency Questionnaire (FFQ). Men with the highest intake of vitamin C had approximately 16% less sperm DNA damage (alkaline sperm Comet) than men with the lowest intake, with similar findings for vitamin E, folate, and zinc (but not β-carotene). Older men (>44 years) with the highest vitamin C intake had approximately 20% less sperm DNA damage compared with older men with the lowest intake, with similar findings for vitamin E and zinc. The older men with the highest intake of these micronutrients showed levels of sperm damage that were similar to those of the younger men. However, younger men (<44 years) did not benefit from higher intakes of the micronutrients surveyed.

CONCLUSION(S)

Men with higher dietary and supplement intake of certain micronutrients may produce sperm with less DNA damage, especially among older men. This raises the broader question of how lifestyle factors, including higher intakes of antioxidants and micronutrients, might protect somatic as well as germ cells against age-associated genomic damage.

Investigating the effects of dietary folic acid on sperm count, DNA damage and mutation in Balb/c mice

To date, fewer than 50 mutagens have been studied for their ability to cause heritable mutations. The majority of those studied are classical mutagens like radiation and anti-cancer drugs. Very little is known about the dietary variables influencing germline mutation rates. Folate is essential for DNA synthesis and methylation and can impact chromatin structure. We therefore determined the effects of folic acid-deficient (0mg/kg), control (2mg/kg) and supplemented (6mg/kg) diets in early development and during lactation or post-weaning on mutation rates and chromatin quality in sperm of adult male Balb/c mice. The sperm chromatin structure assay and mutation frequencies at expanded simple tandem repeats (ESTRs) were used to evaluate germline DNA integrity. Treatment of a subset of mice fed the control diet with the mutagen ethylnitrosourea (ENU) at 8 weeks of age was included as a positive control. ENU treated mice exhibited decreased cauda sperm counts, increased DNA fragmentation and increased ESTR mutation frequencies relative to non-ENU treated mice fed the control diet. Male mice weaned to the folic acid deficient diet had decreased cauda sperm numbers, increased DNA fragmentation index, and increased ESTR mutation frequency. Folic acid deficiency in early development did not lead to changes in sperm counts or chromatin integrity in adult mice. Folic acid supplementation in early development or post-weaning did not affect germ cell measures. Therefore, adequate folic acid intake in adulthood is important for preventing chromatin damage and mutation in the male germline. Folic acid supplementation at the level achieved in this study does not improve nor is it detrimental to male germline chromatin integrity.

Oxidative stress and fertility: incorrect assumptions and ineffective solutions?

One of the most important concerns in assisted reproduction (ART), and in particular ICSI, is the quality of sperm DNA. Oxidative stress is one of the major causes of damage to DNA and attempting to reduce generation of DNA damage related to reactive oxygen species (ROS) through consumption of antioxidants is often tempting. However, current antioxidant treatments, given irrespectively of clinically quantified deficiencies, are poorly efficient, potentially detrimental and over-exposure is risky. Here we discuss new treatments in relation to present day concepts on oxidative stress. This discussion includes stimulation of endogenous anti-ROS defense i.e. glutathione synthesis and recycling of homocysteine, the epicentre of multiple ROS-linked pathologies.

Parental diet and risk of retinoblastoma resulting from new germline RB1 mutation

We conducted a case-control study of sporadic bilateral retinoblastoma, which results from a new germline RB1 mutation, to investigate the role of parents' diet before their child's conception. Parents of 206 cases from nine North American institutions and 269 controls participated; of these, fathers of 184 cases and 223 controls and mothers of 204 cases and 260 controls answered a food frequency questionnaire administered by phone about their diet in the year before the child's conception. Cases provided DNA for RB1 mutation testing. We assessed parents' diet by examining 19 food groups. Father's intake of dairy products and fruit was associated with decreased risk and cured meats and sweets with increased risk. Mother's intake was not associated with disease for any food group. Considering analyses adjusted for the other food groups significantly associated with disease, energy intake, and demographic characteristics as well as more fully adjusted models, the associations with father's dairy products and cured meat intake were the most robust. In the fully adjusted, matched analysis, the odds ratios per daily serving were 0.70 (95% confidence interval (CI) 0.49-1.00, P = 0.047) for dairy products and 5.05 (CI 1.46-17.51, P = 0.01) for cured meat. The pattern of associations with paternal but not maternal diet is consistent with the fact that 85% of new germline RB1 mutations occur on the father's allele. As few human data exist on the role of diet in any condition resulting from new germ-cell mutation, additional studies will be needed to replicate or refute our findings.

Reduction in sperm aneuploidy levels in severe oligoasthenoteratospermic patients after medical therapy: a preliminary report

The objective of this study was to investigate whether medical therapy can reduce sperm aneuploidy levels and improve the results of intracytoplasmic sperm injection (ICSI) in patients with severe idiopathic oligoasthenoteratospermia (OAT). Thirty-three infertile couples requiring ICSI because of severe idiopathic OAT after at least one unsuccessful ICSI cycle were considered. Semen parameters (concentration, motility and morphology), the percentage of aneuploid sperm and the results of ICSI (the number of oocytes fertilized, embryos transferred, biochemical pregnancies, clinical pregnancies and live births) were compared before and after a 3-month course of treatment with L-carnitine 1 g given twice per day+acetyl-L-carnitine 500 mg given twice per day+one 30-mg cinnoxicam tablet every 4 days. Aneuploidy was assessed using fluorescent in situ hybridisation (FISH) performed on chromosomes X, Y, 13, 15, 16, 17, 18, 21 and 22. The results showed that 22 of the 33 patients had a reduced frequency of aneuploid sperm and improved sperm morphology after treatment (group 1), and 11 showed no change (group 2). The numbers of biochemical pregnancies, clinical pregnancies and live births were significantly higher in group 1 than in group 2. No significant difference was found between the groups regarding the numbers of oocytes fertilized and embryos transferred. The side effects were negligible. The numbers of ICSI pregnancies and live births in severe idiopathic OAT patients improved with a course of L-carnitine, acetyl-L-carnitine and cinnoxicam.

Micronucleated lymphocytes in parents of Down syndrome children

Down syndrome (DS) is the most common disease due to an autosomal aneuploidy in live born children and also the major known genetic cause of mental retardation. The risk of a DS pregnancy increases substantially with increasing maternal age. However, several women aged less than 35 years at conception have a child with DS. The micronucleus (MN) assay can identify chromosome breakage or chromosome malsegregation and is an ideal biomarker to investigate genomic instability. The aim of the present study was to determine the frequency of peripheral lymphocytes with MN in the parents of DS individuals. The subjects were 17 couples, 1 father and 9 mothers, and 24 couples who had at least one healthy child formed the control group. For each individual we evaluated the frequency of binucleated micronucleated lymphocytes (BNMN%) as number of binucleated lymphocytes containing one or more MN per 1000 binucleated cells. The mean age of DS parents and controls was 32.6 and 29.8 years, respectively. The frequency of MN in DS parents was significantly higher compared to controls. The higher frequency of MN in DS parents suggests a higher predisposition of DS parents to aneuploidy events in this sample.

Could zinc prevent reproductive alterations caused by cigarette smoke in male rats?

The aim of the present study was to evaluate the effects of zinc on fertility through semen parameters, testosterone level and oxidative DNA damage to spermatozoa of rats exposed to cigarette smoke. Male Wistar rats (60 days old) were divided into four groups (n = 10 per group): control, cigarette-smoking (20 cigarettes per day), zinc (zinc chloride 20 mg kg–1 day–1) and zinc plus cigarette-smoking (zinc chloride 20 mg kg–1 day–1; 20 cigarettes per day). The treatment was applied for nine weeks and the following parameters were analysed: bodyweight, wet weights of the reproductive organs and the adrenal gland, plasma testosterone concentration, testicular function (seminal analysis and daily sperm production) and sperm DNA oxidative damage. The exposure to cigarette smoke decreased testosterone concentration, the percentage of normal morphology and the motility of spermatozoa. In addition, this exposure increased sperm DNA oxidative damage. Zinc treatment protected against the toxic damage that smoking caused to spermatozoa. This study showed a correlation between smoking and possible male infertility and subfertility, and also that the majority of smoking-induced changes in spermatozoa were prevented by zinc treatment. In conclusion, zinc, an antioxidant and stimulant of cell division, can be indicated as a promising treatment in men with infertility caused by the toxic components of cigarette smoke.

The use of fluorescent in situ hybridization in male infertility

Male factors are implicated in up to 50% of couples being evaluated and treated for infertility with advanced assisted reproductive technologies. Genetic abnormalities, including sperm chromosome aneuploidy as well as structural aberrations, are one of the major causes of infertility. The use of chromosome-specific DNA probes labeled with fluorochromes, particularly the combination with multiple probes, has been used to indirectly study the sperm chromosome by fluorescent in situ hybridization (FISH). Clinically, this technique is also used to assess the sperm of men recovering from gonadotoxic treatment. Recent advances in this technology facilitate the evaluation of sperm aneuploidy. Sperm FISH is a widely used screening tool to aid in counseling couples with severe male factor infertility, especially in cases of prior repeated in vitro fertilization/intracytoplasmic sperm injection failure or recurrent pregnancy loss. Automation of FISH imaging and analysis, as well as the development of emerging techniques such as comparative genomic hybridization, will all contribute to the promise of future diagnostic approaches aimed at improving the quality, ease, and efficiency of aneuploidy analysis.

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.

Germinal and Somatic Trisomy 21 Mosaicism: How Common is it, What are the Implications for Individual Carriers and How Does it Come About?

It is well known that varying degrees of mosaicism for Trisomy 21, primarily a combination of normal and Trisomy 21 cells within individual tissues, may exist in the human population. This involves both Trisomy 21 mosaicism occurring in the germ line and Trisomy 21 mosaicism documented in different somatic tissues, or indeed a combination of both in the same subjects. Information on the incidence of Trisomy 21 mosaicism in different tissue samples from people with clinical features of Down syndrome as well as in the general population is, however, still limited. One of the main reasons for this lack of detailed knowledge is the technological problem of its identification, where in particular low grade/cryptic Trisomy 21 mosaicism, i.e. occurring in less than 3-5% of the respective tissues, can only be ascertained by fluorescence in situ hybridization (FISH) methods on large cell populations from the different tissue samples.In this review we summarize current knowledge in this field with special reference to the question on the likely incidence of germinal and somatic Trisomy 21 mosaicism in the general population and its mechanisms of origin. We also highlight the reproductive and clinical implications of this type of aneuploidy mosaicism for individual carriers. We conclude that the risk of begetting a child with Trisomy 21 Down syndrome most likely is related to the incidence of Trisomy 21 cells in the germ line of any carrier parent. The clinical implications for individual carriers may likewise be dependent on the incidence of Trisomy 21 in the relevant somatic tissues. Remarkably, for example, there are indications that Trisomy 21 mosaicism will predispose carriers to conditions such as childhood leukemia and Alzheimer's Disease but there is on the other hand a possibility that the risk of solid cancers may be substantially reduced.

Effect of paternal folate deficiency on placental folate content and folate receptor α expression in rats

We investigated the effect of paternal folate status on folate content and expression of the folate transporter folate receptor α (FRα) in rat placental tissues. Rats were mated after males were fed a diet containing 0 mg of folic acid/kg of diet (paternal folate-deficient, PD) or 8 mg folic acid/kg of diet (paternal folate-supplemented, PS) for 4 weeks. At 20 days of gestation, the litter size, placental weight, and fetal weight were measured, and placental folate content (n = 8/group) and expression of FRα (n = 10/group) were analyzed by microbiological assay and Western blot analysis, respectively. Although there was no difference observed in litter size or fetal weight, but significant reduction (10%) in the weight of the placenta was observed in the PD group compared to that in the PS group. In the PD group, placental folate content was significantly lower (by 35%), whereas FRα expression was higher (by 130%) compared to the PS group. Our results suggest that paternal folate status plays a critical role in regulating placental folate metabolism and transport.

[Cytogenetics of human spermatozoa: which interest?]

Incidence of aneuploidy in human spermatozoa could be detected by various methods for precise indications. Taking in consideration this aneuploidy rate could optimize the ICSI prognosis and genetic counselling.

On the paternal origin of trisomy 21 Down syndrome

BACKGROUND

Down syndrome (DS), characterized by an extra free chromosome 21 is the most common genetic cause for congenital malformations and learning disability. It is well known that the extra chromosome 21 originates from the mother in more than 90% of cases, the incidence increases with maternal age and there is a high recurrence in young women. In a previous report we have presented data to indicate that maternal trisomy 21 (T21) ovarian mosaicism might provide the major causative factor underlying these patterns of DS inheritance. One important outstanding question concerns the reason why the extra chromosome 21 in DS rarely originates from the father, i.e. in less than 10% of T21 DS cases. We here report data indicating that one reason for this parental sex difference is a very much lower degree of fetal testicular in comparison to ovarian T21 mosaicism.

RESULTS

We used fluorescence in situ hybridisation (FISH) with two chromosome 21-specific probes to determine the copy number of chromosome 21 in fetal testicular cell nuclei from four male fetuses, following termination of pregnancy for a non-medical/social reason at gestational age 14-19 weeks. The cells studied were selected on the basis of their morphology alone, pending immunological specification of the relevant cell types. We could not detect any indication of testicular T21 mosaicism in any of these four male fetuses, when analysing at least 2000 cells per case (range 2038-3971, total 11.842). This result is highly statistically significant (p < 0.001) in comparison to the average of 0.54% ovarian T21 mosaicism (range 0.20-0.88%) that we identified in eight female fetuses analysing a total of 12.634 cells, as documented in a previous report in this journal.

CONCLUSION

Based on these observations we suggest that there is a significant sex difference in degrees of fetal germ line T21 mosaicism. Thus, it would appear that most female fetuses are T21 ovarian mosaics, while in sharp contrast most male fetuses may be either very low grade T21 testicular mosaics or they may be non-mosaics. We further propose that this sex difference in germ line T21 mosaicism may explain the much less frequent paternal origin of T21 DS than maternal. The mechanisms underlying the DS cases, where the extra chromosome 21 does originate from the father, remains unknown and further studies in this respect are required.

Toxicants and human sperm chromatin integrity

The integrity of the paternal genome is essential as the spermatozoon can bring genetic damage into the oocyte at fertilization and contribute to the development of abnormal pregnancy outcome. During the past two decades, many assays have been developed to measure sperm DNA strand breaks, chromatin structure and compaction and assess the proteins associated with the DNA, as well as epigenetic modifications. Using these assays, it has been shown that exposure to physical agents or chemicals, including therapeutic drugs and environmental toxicants, can affect the integrity of sperm chromatin, inducing structural, genetic and/or epigenetic abnormalities. The mechanisms by which such damage is triggered are still largely unresolved and the susceptibility of each individual will depend on their genetic background, lifestyle and exposure to various insults. Depending on the nature of the chemicals, they may directly target the DNA, induce an oxidative stress, or modify the epigenetic elements. The significance of measuring the sperm chromatin integrity comes from the fact that this end-point correlates well with the low IVF and ICSI outcomes, and idiopathic infertility. Nevertheless, it is hard to establish a direct link between the paternal sperm chromatin integrity and the health of the future generations. Thus, it seems essential to undertake studies that will resolve the impact of chemical and environmental factors on chromatin structure and epigenetic components of human spermatozoa and to elucidate what sperm nuclear end-points are predictors of the quality of progeny outcome.

Role of antioxidants in the treatment of male infertility

Male infertility continues to be a clinical challenge of increasing significance. While male factors such as decreased semen quality are responsible for 25% of all infertility issues, the etiology of suboptimal semen quality is poorly understood. Many physiological, environmental, and genetic factors have been implicated, including oxidative stress. Oxidative stress is induced by reactive oxygen species (ROS), or free radicals, and although ROS are required for critical aspects of sperm function, excessive levels of ROS can negatively impact sperm quality. The origin of ROS generation, and the etiologies of increased ROS in men with suboptimal sperm quality have only recently been elucidated, offering multiple targets for potential therapy. Here, we present a critical review of the literature describing the role of oxidative stress on decreased sperm function, as well as the role of antioxidants in the treatment of male factor infertility.

Associations between dietary patterns and semen quality in men undergoing IVF/ICSI treatment

BACKGROUND This study investigates whether dietary patterns, substantiated by biomarkers, are associated with semen quality. METHODS In 161 men of subfertile couples undergoing in vitro fertilization treatment in a tertiary referral clinic in Rotterdam, the Netherlands, we assessed nutrient intakes and performed principal component factor analysis to identify dietary patterns. Total homocysteine (tHcy), folate, vitamin B12 and B6 were measured in blood and seminal plasma. Semen quality was assessed by sperm volume, concentration, motility, morphology and DNA fragmentation index (DFI). Linear regression models analyzed associations between dietary patterns, biomarkers and sperm parameters, adjusted for age, body mass index (BMI), smoking, vitamins and varicocele. RESULTS The 'Health Conscious' dietary pattern shows high intakes of fruits, vegetables, fish and whole grains. The 'Traditional Dutch' dietary pattern is characterized by high intakes of meat, potatoes and whole grains and low intakes of beverages and sweets. The 'Health Conscious' diet was inversely correlated with tHcy in blood (beta = -0.07, P = 0.02) and seminal plasma (beta = -1.34, P = 0.02) and positively with vitamin B6 in blood (beta = 0.217, P = 0.01). An inverse association was demonstrated between the 'Health Conscious' diet and DFI (beta = -2.81, P = 0.05). The 'Traditional Dutch' diet was positively correlated with red blood cell folate (beta = 0.06, P = 0.04) and sperm concentration (beta = 13.25, P = 0.01). CONCLUSIONS The 'Health Conscious' and 'Traditional Dutch' dietary pattern seem to be associated with semen quality in men of subfertile couples.

A low intake of antioxidant nutrients is associated with poor semen quality in patients attending fertility clinics

OBJECTIVE

To compare specific nutrient intake between normospermic and oligoasthenoteratospermic patients attending infertility clinics in two Mediterranean provinces of Spain.

DESIGN

Case-control study.

SETTING

Private fertility clinics in southeastern Spain.

PATIENT(S)

Thirty men with poor semen quality (case subjects) and 31 normospermic control subjects of couples attending our fertility clinics.

INTERVENTION(S)

We recorded dietary habits and nutrient consumption using a food frequency questionnaire adapted to meet specific study objectives.

MAIN OUTCOME MEASURE(S)

We calculated nutrient intakes by multiplying the frequency of use for each food by the nutrient composition of the portion size specified on the food frequency questionnaire and by addition across all foods to obtain a total nutrient intake for each individual. Semen quality was assessed by measuring volume, concentration, motility, and morphology. Hormones levels were also analyzed in case and control subjects.

RESULT(S)

In the logistic regression, control subjects had a significantly higher intake of carbohydrates, fiber, folate, vitamin C, and lycopene and lower intakes of proteins and total fat.

CONCLUSION(S)

A low intake of antioxidant nutrients was associated with a poor semen quality in this case-control study of Spanish men attending infertility clinics.

Methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms resulting in suboptimal oocyte maturation: a discussion of folate status, neural tube defects, schizophrenia, and vasculopathy

Several conditions apparent at birth, e.g., neural tube defects (NTDs) and cardiac anomalies, are associated with polymorphisms in folate-related genes, such as the 677C → T polymorphism of the methylenetetrahydrofolate reductase (MTHFR) gene. Similar associations have been established for several constitutional chronic diseases in adulthood, such as schizophrenia, cardiovascular diseases, dementia, and even neoplasias in different organ systems. This spectrum of developmental anomalies and constitutional diseases may be linked to high-risk conceptions related to preovulatory overripeness ovopathy (PrOO). Some developmental anomalies, such as NTDs, are to a large extent prevented by supplementation of folic acid before conception, but supplementation does not seem to prevent cardiovascular disease or cognitive decline. These diverging results can be elucidated by introduction of the PrOO concept, as MTHFR polymorphisms and inherent low folate levels induce both non-optimal maturation of the oocyte and unsuccessful DNA methylation and demethylation, i.e. epigenetic mutations. The PrOO concept is testable and predicts in a random population the following: (1) female carriers of specific genetic MTHFR variants exhibit more ovulatory disturbances and inherent subfecundity traits, (2) descendents from a carrier mother, when compared with those from a wild-type mother, are more frequently conceived in PrOO high-risk conditions and, thus, (3) disadvantaged in life expectancy. If so, some MTHFR polymorphisms represent a novel, genetically determined, PrOO high-risk conception category comparable to those which are environmentally and behaviorly influenced. These high-risk conditions may cause developmental anomalies and defective epigenetic reprogramming in progeny. The interaction between genetic and environmental factors is a plausible mechanism of multifactorial inheritance.