Are UMFA (un-metabolized folic acid) and endocrine disruptor chemicals (EDCs) co-responsible for sperm degradation? An epigenetic/methylation perspective

Hyperhomocysteinemia in hypofertile male patients can be alleviated by supplementation with 5MTHF associated with one carbon cycle support

Introduction

Homocysteine (Hcy) is a cellular poison, side product of the hydrolysis of S-Adenosyl Homocysteine, produced after the universal methylation effector S -Adenosylmethionine liberates a methyl group to recipient targets. It inhibits the methylation processes and its rising is associated with multiple disease states and ultimately is both a cause and a consequence of oxidative stress, affecting male gametogenesis. We have determined hyper homocysteinhemia (HHcy) levels can be reliably reduced in hypofertile patients in order to decrease/avoid associated epigenetic problems and protect the health of future children, in consideration of the fact that treatment with high doses of folic acid is inappropriate.

Methods

Homocysteine levels were screened in male patients consulting for long-standing infertility associated with at least three failed Assisted Reproductive Technology (ART) attempts and/or repeat miscarriages. Seventy-seven patients with Hcy levels > 15 µM were treated for three months with a combination of micronutrients including 5- MethylTetraHydroFolate (5-MTHF), the compound downstream to the MTHFR enzyme, to support the one carbon cycle; re-testing was performed at the end of a 3 months treatment period. Genetic status for Methylenetetrahydrofolate Reductase (MTHFR) Single nucleotide polymorphisms (SNPs) 677CT (c.6777C > T) and 1298AC (c.1298A > C) was determined.

Results

Micronutrients/5-MTHF were highly efficient in decreasing circulating Hcy, from averages 27.4 to 10.7 µM, with a mean observed decrease of 16.7 µM. The MTHFR SNP 677TT (homozygous form) and combined heterozygous 677CT/1298AC status represent 77.9% of the patients with elevated Hcy.

Discussion

Estimation HHcy should not be overlooked in men suffering infertility of long duration. MTHFR SNPs, especially 677TT, are a major cause of high homocysteinhemia (HHcy). In these hypofertile patients, treatment with micronutrients including 5-MTHF reduces Hcy and even allows spontaneous pregnancies post treatment. This type of therapy should be considered in order to ensure these patients' quality of life and avoid future epigenetic problems in their descendants.

T677T Methylenetetrahydrofolate Reductase Single Nucleotide Polymorphisms Increased Prevalence in a Subgroup of Infertile Patients with Endometriosis

<b><i>Background:</i></b> Approximately 10% (190 million) of women worldwide are affected by endometriosis, ectopic deposits of endometrial tissue that create a major source of pain that affects lifestyle and reproductive function. The pathogenesis of endometriosis is an estrogen-dependent inflammatory process, influenced/catalyzed by oxidative stress and consequently defective methylation, with biochemical features centered around the folate and one-carbon cycles. We aimed to determine whether a link could be found between the two major methylenetetrahydrofolate reductase single nucleotide polymorphisms (MTHFR SNPs), c.677C&gt;T and c.1298A&gt;C, involved in methylation process/epigenetic marking failures, and endometriosis. <b><i>Material and Methods:</i></b> We studied a population of 158 patients in a group of &gt;1500 referred for treatment of infertility. All the patients had experienced &gt;2 failed assisted reproductive technology cycles and/or &gt;2 miscarriages, a classical cohort for investigation in our group. Patients with endometriosis had at least stage 2+ disease confirmed by laparoscopy. <b><i>Results:</i></b> The prevalence of the homozygous c.677C&gt;T isoform is doubled in the endometriosis group, 21.5% versus 10.2% in the non-endometriosis group (<i>p</i> &gt; 0.01). Symmetrically, the percentage of patients in the endometriosis group with the wild type MTHFR significantly decreased by one-half (8.2%-17.2%) in the non-endometriosis group (<i>p</i> &lt; 0.001). <b><i>Conclusion:</i></b> Determination of MTHFR c.677C&gt;T should not be overlooked in patients with harmful endometriosis affecting their fertility. As folates metabolism is impaired in these MTHFR SNPs carrier patients, co-treatment with 5-methyl folate may constitute a successful (co)-treatment modality.

Biochemical Hazards during Three Phases of Assisted Reproductive Technology: Repercussions Associated with Epigenesis and Imprinting

Medically assisted reproduction, now considered a routine, successful treatment for infertility worldwide, has produced at least 8 million live births. However, a growing body of evidence is pointing toward an increased incidence of epigenetic/imprinting disorders in the offspring, raising concern that the techniques involved may have an impact on crucial stages of early embryo and fetal development highly vulnerable to epigenetic influence. In this paper, the key role of methylation processes in epigenesis, namely the essential biochemical/metabolic pathways involving folates and one-carbon cycles necessary for correct DNA/histone methylation, is discussed. Furthermore, potential contributors to epigenetics dysregulation during the three phases of assisted reproduction: preparation for and controlled ovarian hyperstimulation (COH); methylation processes during the preimplantation embryo culture stages; the effects of unmetabolized folic acid (UMFA) during embryogenesis on imprinting methyl “tags”, are described. Advances in technology have opened a window into developmental processes that were previously inaccessible to research: it is now clear that ART procedures have the potential to influence DNA methylation in embryonic and fetal life, with an impact on health and disease risk in future generations. Critical re-evaluation of protocols and procedures is now an urgent priority, with a focus on interventions targeted toward improving ART procedures, with special attention to in vitro culture protocols and the effects of excessive folic acid intake.