Ultrastructural Analysis of Large Japanese Field Mouse (Apodemus speciosus) Testes Exposed to Low-Dose-Rate (LDR) Radiation after the Fukushima Nuclear Power Plant Accident.

Since the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident, great attention has been paid to the impact of chronic low-dose-rate (LDR) radiation exposure on biological systems. The reproductive system is sensitive to radiation, with implications connected to infertility. We investigated the testis ultrastructure of the wild large Japanese field mouse (Apodemus speciosus) from three areas contaminated after the FDNPP accident, with different levels of LDR radiation (0.29 µSv/h, 5.11 µSv/h, and 11.80 µSv/h). Results showed good preservation of the seminiferous tubules, comparable to the unexposed animals (controls), except for some ultrastructural modifications. Increases in the numerical density of lipid droplet clusters in spermatogenic cells were found at high levels of LDR radiation, indicating an antioxidant activity rising due to radiation recovery. In all groups, wide intercellular spaces were found between spermatogenic cells, and cytoplasmic vacuolization increased at intermediate and high levels and vacuolated mitochondria at the high-level. However, these findings were also related to the physiological dynamics of spermatogenesis. In conclusion, the testes of A. speciosus exposed to LDR radiation associated with the FDNPP accident showed a normal spermatogenesis, with some ultrastructural changes. These outcomes may add information on the reproductive potential of mammals chronically exposed to LDR radiation.

Heavy Metals in Follicular Fluid Affect the Ultrastructure of the Human Mature Cumulus-Oocyte Complex.

It is known that exposure to heavy metal such as lead (Pb) and cadmium (Cd) has several adverse effects, particularly on the human reproductive system. Pb and Cd have been associated with infertility in both men and women. In pregnant women, they have been associated with spontaneous abortion, preterm birth, and impairment of the development of the fetus. Since these heavy metals come from both natural and anthropogenic activities and their harmful effects have been observed even at low levels of exposure, exposure to them remains a public health issue, especially for the reproductive system. Given this, the present study aimed to investigate the potential reproductive effects of Pb and Cd levels in the follicular fluid (FF) of infertile women and non-smokers exposed to heavy metals for professional reasons or as a result of living in rural areas near landfills and waste disposal areas in order to correlate the intrafollicular presence of these metals with possible alterations in the ultrastructure of human cumulus-oocyte complexes (COCs), which are probably responsible for infertility. Blood and FF metals were measured using atomic absorption spectrometry. COCs corresponding to each FF analyzed were subjected to ultrastructural analyses using transmission electron microscopy. We demonstrated for the first time that intrafollicular levels of Pb (0.66 µg/dL-0.85 µg/dL) and Cd (0.26 µg/L-0.41 µg/L) could be associated with morphological alterations of both the oocyte and cumulus cells' (CCs) ultrastructure. Since blood Cd levels (0.54 µg/L-1.87 µg/L) were above the current reference values established by the guidelines of the Agency for Toxic Substances and Disease Registry (ATSDR) and the Environmental Protection Agency (EPA) (0.4 µg/L), whereas blood Pb levels (1.28 µg/dL-3.98 µg/dL) were below the ATSDR reference values (≤5 µg/dL), we believe that these alterations could be due especially to Cd, even if we cannot exclude a possible additional effect of Pb. Our results highlighted that oocytes were affected in maturation and quality, whereas CCs showed scarcely active steroidogenic elements. Regressing CCs, with cytoplasmic alterations, were also numerous. According to Cd's endocrine-disrupting activity, the poor steroidogenic activity of CCs might correlate with delayed oocyte cytoplasmic maturation. So, we conclude that levels of heavy metals in the blood and the FF might negatively affect fertilization, embryo development, and pregnancy, compromising oocyte competence in fertilization both directly and indirectly, impairing CC steroidogenic activity, and inducing CC apoptosis.

Self-assembly of glycoprotein nanostructured filaments for modulating extracellular networks at long range.

The intriguing capability of branched glycoprotein filaments to change their hierarchical organization, mediated by external biophysical stimuli, continues to expand understanding of self-assembling strategies that can dynamically rearrange networks at long range. Previous research has explored the corresponding biological, physiological and genetic mechanisms, focusing on protein assemblies within a limited range of nanometric units. Using direct microscopy bio-imaging, we have determined the morpho-structural changes of self-assembled filament networks of the zona pellucida, revealing controlled levels of structured organizations to join distinct evolved stages of the oocyte (Immature, Mature, and Fertilized). This natural soft network reorganizes its corresponding hierarchical network to generate symmetric, asymmetric, and ultimately a state with the lowest asymmetry of the outer surface roughness, and internal pores reversibly changed from elliptical to circular configurations at the corresponding stages. These elusive morpho-structural changes are regulated by the nanostructured polymorphisms of the branched filaments by self-extension/-contraction/-bending processes, modulated by determinate theoretical angles among repetitive filament units. Controlling the nanoscale self-assembling properties by delivering a minimum number of activation bio-signals may be triggered by these specific nanostructured polymorphic organizations. Finally, this research aims to guide this soft biomaterial into a desired state to protect oocytes, eggs, and embryos during development, to favour/prevent the fertilization/polyspermy processes and eventually to impact interactions with bacteria/virus at multiscale levels.

Retinoic acid and proteotoxic stress induce AML cell death overcoming stromal cell protection.

BACKGROUND: Acute myeloid leukemia (AML) patients bearing the ITD mutation in the tyrosine kinase receptor FLT3 (FLT3-ITD) present a poor prognosis and a high risk of relapse. FLT3-ITD is retained in the endoplasmic reticulum (ER) and generates intrinsic proteotoxic stress. We devised a strategy based on proteotoxic stress, generated by the combination of low doses of the differentiating agent retinoic acid (R), the proteasome inhibitor bortezomib (B), and the oxidative stress inducer arsenic trioxide (A). METHODS: We treated FLT3-ITD+ AML cells with low doses of the aforementioned drugs, used alone or in combinations and we investigated the induction of ER and oxidative stress. We then performed the same experiments in an in vitro co-culture system of FLT3-ITD+ AML cells and bone marrow stromal cells (BMSCs) to assess the protective role of the niche on AML blasts. Eventually, we tested the combination of drugs in an orthotopic murine model of human AML. RESULTS: The combination RBA exerts strong cytotoxic activity on FLT3-ITD+ AML cell lines and primary blasts isolated from patients, due to ER homeostasis imbalance and generation of oxidative stress. AML cells become completely resistant to the combination RBA when treated in co-culture with BMSCs. Nonetheless, we could overcome such protective effects by using high doses of ascorbic acid (Vitamin C) as an adjuvant. Importantly, the combination RBA plus ascorbic acid significantly prolongs the life span of a murine model of human FLT3-ITD+ AML without toxic effects. Furthermore, we show for the first time that the cross-talk between AML and BMSCs upon treatment involves disruption of the actin cytoskeleton and the actin cap, increased thickness of the nuclei, and relocalization of the transcriptional co-regulator YAP in the cytosol of the BMSCs. CONCLUSIONS: Our findings strengthen our previous work indicating induction of proteotoxic stress as a possible strategy in FLT3-ITD+ AML therapy and open to the possibility of identifying new therapeutic targets in the crosstalk between AML and BMSCs, involving mechanotransduction and YAP signaling.

A New Strong-Acid Free Route to Produce Xanthan Gum-PANI Composite Scaffold Supporting Bioelectricity.

Conductive hybrid xanthan gum (XG)-polyaniline (PANI) biocomposites forming 3D structures able to mimic electrical biological functions are synthesized by a strong-acid free medium. In situ aniline oxidative chemical polymerizations are performed in XG water dispersions to produce stable XG-PANI pseudoplastic fluids. XG-PANI composites with 3D architectures are obtained by subsequent freeze-drying processes. The morphological investigation highlights the formation of porous structures; UV-vis and Raman spectroscopy characterizations assess the chemical structure of the produced composites. I-V measurements evidence electrical conductivity of the samples, while electrochemical analyses point out their capability to respond to electric stimuli with electron and ion exchanges in physiological-like environment. Trial tests on prostate cancer cells evaluate biocompatibility of the XG-PANI composite. Obtained results demonstrate that a strong acid-free route produces an electrically conductive and electrochemically active XG-PANI polymer composite. The investigation of charge transport and transfer, as well as of biocompatibility properties of composite materials produced in aqueous environments, brings new perspective for exploitation of such materials in biomedical applications. In particular, the developed strategy can be used to realize biomaterials working as scaffolds that require electrical stimulations for inducing cell growth and communication or for biosignals monitoring and analysis.

Sorcin promotes migration in cancer and regulates the EGF-dependent EGFR signaling pathways.

The epidermal growth factor receptor (EGFR) is one of the main tumor drivers and is an important therapeutic target for many cancers. Calcium is important in EGFR signaling pathways. Sorcin is one of the most important calcium sensor proteins, overexpressed in many tumors, that promotes cell proliferation, migration, invasion, epithelial-to-mesenchymal transition, malignant progression and resistance to chemotherapeutic drugs. The present work elucidates a functional mechanism that links calcium homeostasis to EGFR signaling in cancer. Sorcin and EGFR expression are significantly correlated and associated with reduced overall survival in cancer patients. Mechanistically, Sorcin directly binds EGFR protein in a calcium-dependent fashion and regulates calcium (dys)homeostasis linked to EGF-dependent EGFR signaling. Moreover, Sorcin controls EGFR proteostasis and signaling and increases its phosphorylation, leading to increased EGF-dependent migration and invasion. Of note, silencing of Sorcin cooperates with EGFR inhibitors in the regulation of migration, highlighting calcium signaling pathway as an exploitable target to enhance the effectiveness of EGFR-targeting therapies.

Ultrastructural Evaluation of Mouse Oocytes Exposed In Vitro to Different Concentrations of the Fungicide Mancozeb.

Mancozeb is a widely used fungicide, considered to be an endocrine disruptor. In vivo and in vitro studies evidenced its reproductive toxicity on mouse oocytes by altering spindle morphology, impairing oocyte maturation, fertilization, and embryo implantation. Mancozeb also induces dose-dependent toxicity on the ultrastructure of mouse granulosa cells, including chromatin condensation, membrane blebbing, and vacuolization. We evaluated the effects on the ultrastructure of mouse oocytes isolated from cumulus-oocyte complexes (COCs), exposed in vitro to increasing concentrations of mancozeb. COCs were matured in vitro with or without (control) low fungicide concentrations (0.001-1 µg/mL). All mature oocytes were collected and prepared for light and transmission electron microscopy. Results showed a preserved ultrastructure at the lowest doses (0.001-0.01 µg/mL), with evident clusters of round-to-ovoid mitochondria, visible electron-dense round cortical granules, and thin microvilli. Mancozeb concentration of 1 µg/mL affected organelle density concerning controls, with a reduction of mitochondria, appearing moderately vacuolated, cortical granules, and microvilli, short and less abundant. In summary, ultrastructural data revealed changes mainly at the highest concentration of mancozeb on mouse oocytes. This could be responsible for the previously described impaired capability in oocyte maturation, fertilization, and embryo implantation, demonstrating its impact on the reproductive health and fertility.

Deeply in Plasticenta: Presence of Microplastics in the Intracellular Compartment of Human Placentas.

Microplastics (MPs) are defined as plastic particles smaller than 5 mm. They have been found almost everywhere they have been searched for and recent discoveries have also demonstrated their presence in human placenta, blood, meconium, and breastmilk, but their location and toxicity to humans have not been reported to date. The aim of this study was twofold: 1. To locate MPs within the intra/extracellular compartment in human placenta. 2. To understand whether their presence and location are associated with possible structural changes of cell organelles. Using variable pressure scanning electron microscopy and transmission electron microscopy, MPs have been localized in ten human placentas. In this study, we demonstrated for the first time the presence and localization in the cellular compartment of fragments compatible with MPs in the human placenta and we hypothesized a possible correlation between their presence and important ultrastructural alterations of some intracytoplasmic organelles (mitochondria and endoplasmic reticulum). These alterations have never been reported in normal healthy term pregnancies until today. They could be the result of a prolonged attempt to remove and destroy the plastic particles inside the placental tissue. The presence of virtually indestructible particles in term human placenta could contribute to the activation of pathological traits, such as oxidative stress, apoptosis, and inflammation, characteristic of metabolic disorders underlying obesity, diabetes, and metabolic syndrome and partially accounting for the recent epidemic of non-communicable diseases.

Oxidative stress and visual system: a review.

Different types of tissues respond differently to the action of oxidative stress. The visual system is very sensitive to oxidative action due to continuous exposure to light. In consideration of the growing interest of scientific studies towards various compounds endowed with antioxidant and anti-inflammatory properties, we performed a review of the literature focusing on the use of some antioxidant molecules for the treatment of conditions affecting the visual system. In this study, we focused on the ability of two antioxidant agents, the small molecule α-lipoic acid (ALA) and the enzyme superoxide dismutase (SOD), to influence the neurodegenerative physiological processes related to aging and oxidative stress affecting the ocular segment. The literature data report that ALA and SOD can protect against neurodegenerative effects both the optic nerve and retina and, if administered together, they are able to lower the levels of oxidative stress, thus preventing neurodegeneration and reducing the apoptotic process.

Ultrastructural Evaluation of the Human Oocyte at the Germinal Vesicle Stage during the Application of Assisted Reproductive Technologies.

After its discovery in 1825 by the physiologist J.E. Purkinje, the human germinal vesicle (GV) attracted the interest of scientists. Discarded after laparotomy or laparoscopic ovum pick up from the pool of retrieved mature oocytes, the leftover GV was mainly used for research purposes. After the discovery of Assisted Reproductive Technologies (ARTs) such as in vitro maturation (IVM), in vitro fertilization and embryo transfer (IVF-ET) and intracytoplasmic sperm injection (ICSI), its developing potential was explored, and recognized as an important source of germ cells, especially in the case of scarce availability of mature oocytes for pathological/clinical conditions or in the case of previous recurrent implantation failure. We here review the ultrastructural data available on GV-stage human oocytes and their application to ARTs.

RIPK4 regulates cell-cell adhesion in epidermal development and homeostasis.

Epidermal development and maintenance are finely regulated events requiring a strict balance between proliferation and differentiation. Alterations in these processes give rise to human disorders such as cancer or syndromes with skin and annexes defects, known as ectodermal dysplasias (EDs). Here, we studied the functional effects of two novel receptor-interacting protein kinase 4 (RIPK4) missense mutations identified in siblings with an autosomal recessive ED with cutaneous syndactyly, palmoplantar hyperkeratosis and orofacial synechiae. Clinical overlap with distinct EDs caused by mutations in transcription factors (i.e. p63 and interferon regulatory factor 6, IRF6) or nectin adhesion molecules was noticed. Impaired activity of the RIPK4 kinase resulted both in altered epithelial differentiation and defective cell adhesion. We showed that mutant RIPK4 resulted in loss of PVRL4/nectin-4 expression in patient epidermis and primary keratinocytes, and demonstrated that PVRL4 is transcriptionally regulated by IRF6, a RIPK4 phosphorylation target. In addition, defective RIPK4 altered desmosome morphology through modulation of plakophilin-1 and desmoplakin. In conclusion, this work implicates RIPK4 kinase function in the p63-IRF6 regulatory loop that controls the proliferation/differentiation switch and cell adhesion, with implications in ectodermal development and cancer.

Ultrastructure of mitochondria of human oocytes in different clinical conditions during assisted reproduction.

Infertility affects around 8% of couples with a slight change in percentage in the last years. Despite the significant efforts made in Assisted Reproductive Technologies (ARTs) in handling this disorder, oocyte quality remains a crucial factor for a positive outcome. A better understanding of the dynamics underlying oocyte maturation, fertilization, and embryo development remains one of the main areas for progress in the ARTs field. Mitochondria are believed to play an essential role in these processes. Mitochondria have a crucial part in producing energy for oocyte maturation and embryo development throughout precise cellular functions comprising Ca2+ homeostasis regulation, glycolysis, amino acid and fatty acid metabolism, and regulation of apoptosis. Recent studies suggest that mitochondrial structure, content, and function may be related to oocyte competence, embryo viability, and implantation success during ARTs. Their defects could lead to low fertilization rates and embryonic development failure. This review aimed to provide an overview of the available literature data surrounding the correlation between changes at ultrastructural level of mitochondria or correlated-mitochondrial aggregates and oocyte quality and ARTs treatments. Our reported data demonstrated that oocyte mitochondrial ultrastructural alterations could be partial or complete recovery during the early embryo stages. However, these changes could persist as quiescent during the pre-implantation embryo development, causing abnormalities that become evident only during fetal and postnatal life. These factors led to consider the mitochondria as a crucial marker of oocyte and embryo quality, as well as a strategic target for further prospective therapeutical approaches.

Does in vitro application of pentoxifylline have beneficial effects in assisted male reproduction?

Application of nonspecific phosphodiesterases inhibitors, such as pentoxifylline (PTX), is a strategy utilised to aid sperm selection from immotile sperm samples prior to ICSI. No extensive studies have yet been performed to verify the safety of the clinical outcomes of ICSI after PTX administration. In this article, we summarise the data reported in the literature that assess the implication of in vitro usage of PTX on sperm parameters, as well as clinical outcomes during assisted male reproduction programme.

Pre-Implantation Mouse Embryos Cultured In Vitro under Different Oxygen Concentrations Show Altered Ultrastructures.

Assisted Reproductive Technologies routinely utilize different culture media and oxygen (O2) concentrations to culture human embryos. Overall, embryos cultured under physiological O2 tension (5%) have improved development compared to embryos cultured under atmospheric O2 conditions (20%). The mechanisms responsible for this remain unclear. This study aimed to evaluate the effect of physiologic (5%) or atmospheric O2 (20%) tension on the microscopic ultrastructure of pre-implantation mouse embryos using Transmission Electron Microscopy (TEM). Embryos flushed out of the uterus after natural mating were used as the control. For use as the control, 2-cells, 4-cells, morulae, and blastocysts were flushed out of the uterus after natural fertilization. In vitro fertilization (IVF) was performed using potassium simplex optimized medium (KSOM) under different O2 tensions (5% and 20%) until the blastocyst stage. After collection, embryos were subjected to the standard preparative for light microscopy (LM) and TEM. We found that culture in vitro under 5% and 20% O2 results in an increase of vacuolated shaped mitochondria, cytoplasmic vacuolization and presence of multi-vesicular bodies at every embryonic stage. In addition, blastocysts generated by IVF under 5% and 20% O2 showed a lower content of heterochromatin, an interruption of the trophectodermal and inner cell mass cell membranes, an increased density of residual bodies, and high levels of glycogen granules in the cytoplasm. In conclusion, this study suggests that in vitro culture, particularly under atmospheric O2 tension, causes stage-specific changes in preimplantation embryo ultrastructure. In addition, atmospheric (20%) O2 is associated with increased alterations in embryonic ultrastructure; these changes may explain the reduced embryonic development of embryos cultured with 20% O2.

Repeated hyperstimulation affects the ultrastructure of mouse fallopian tube epithelium.

Controlled ovarian hyperstimulation (COH) is routinary used in assisted reproductive technologies (ARTs) to increase the yields of mature oocytes. The possibility that patients with a history of failures or poor-responders may develop side-effects following these treatments is still debated. Epidemiological studies reported controversial results about pregnancy outcome and the risk of developing gynecological cancers. By using a mouse model, here we compared the ultrastructural features of fallopian tubes (FTs) obtained from mice undergoing or not (control, CTR) four (4R) and eight (8R) rounds of gonadotropin stimulation. Although the morphological characteristics of oviductal layers seemed unaffected by repeated treatments, dose-response ultrastructural alterations in the ampulla appeared in the 4R group and even more in the 8R group. The targets were oviductal ciliated (CCs) and non-ciliated (NCCs) cells, which showed damaged mitochondria and glycogen accumulations in the cytoplasm. The drastic reduction of CCs, evident after 4R, was supported by the absence of cilia. After 8R, glycogen granules were significantly reduced and massive degeneration of mitochondria, which appeared swollen and/or vacuolated, occurred in NCCs. Moreover, disintegrated mitochondria were found at the periphery of mitophagic vacuoles with evident signs of cristolysis. The morphometric analysis evidenced a significant increase in the density and frequency of damaged mitochondria after 4R and 8R. The absence of cilia, necessary to sustain oviductal transport of oocytes, spermatozoa and embryos, may originate from either mitochondrial dysfunction or glycogen consumption. These results suggest that repeated COH treatments could induce alterations impairing fertilization and embryo transport toward the uterus.

The effect of low and ultra-low oxygen tensions on mammalian embryo culture and development in experimental and clinical IVF.

Over the last forty years, many trials have been performed using mammalian embryo cultures with reduced oxygen tension (O2) to encourage proper embryo development and increase the success rate for in vitro fertilization (IVF) outcome. Even if the use of atmospheric O2 (20%) affects in vitro embryo development and intracellular redox balance, the use of low (5% O2, physiologic) and ultra-low (close or less to 5% O2) O2 applied to in vitro embryo culture is still under debate. Numerous studies in various mammalian species have shown that embryo development improves when culturing embryos under low O2, although culture conditions are not the only factors involved in the success of IVF. This article reviews the literature data of the last four decades and discusses the current evidence on the use of low and ultra-low O2 in embryo culture, and examines the impact of multiple factors on IVF outcomes. ABBREVIATIONS: O2: oxygen tension; IVF: in vitro fertilization; IVC: in vitro culture; ET: embryo transfer; ROS: reactive oxygen species; ARTs: assisted reproductive technologies.

Association between Female Reproductive Health and Mancozeb: Systematic Review of Experimental Models.

Mancozeb is a widely used fungicide approved for use in agriculture in many countries with long persistence in the environment and consequent bioaccumulation in tissues and biological fluids. Despite the large amount of studies published in recent years, the relationship between mancozeb exposure and female reproductive health is not fully elucidated. In order to summarize current evidence on mancozeb exposure and female reproductive disease, we performed a systematic review of literature. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were used to make this review. An adapted version of the National Toxicology Program's Office of Health and Assessment and Translation (OHAT) framework was used to evaluate the risk of bias. Electronic search on two databases (PubMed and Scopus) was used to find experimental studies (in vitro and in vivo) on mancozeb exposure. The database search identified 250 scientific articles, 20 of which met our inclusion criteria. Selected data were then reviewed and summarized in tables. Overall, mancozeb represents a hazard for female reproductive health, with different mechanisms of action. Undoubtedly more experimental and epidemiological studies are required to definitively validate mancozeb as reproductive toxicant.

Type of protein supplement in cryopreservation solutions impacts on the degree of ultrastructural damage in frozen-thawed human oocytes.

Protein sources used as supplements of IVF culture media are known to have several implications for the function and stability of embryo culture environment. In fact, they i) transport biologically active molecules ii) chelate heavy metals, iii) regulate media pH, iii) scavenge reactive oxygen species (ROS) and iv) attenuate osmotic stress to which cells are exposed in sub-optimal culture conditions. Instead, their specific relevance to the formulation of cryopreservation solutions used for gamete and embryo cryopreservation remains uncertain. In the present work, we tested the hypothesis that different protein supplements present in cryopreservation solutions, serum or plasma protein solution (PPS), or different concentrations of the same supplement (serum), are associated with different types and/or magnitude of cryopreservation-derived cell damage. To this end, using cryopreservation solutions containing serum or PPS, donated supernumerary human mature oocytes were frozen-thawed by slow freezing and compared with fresh controls. Ultrastructural markers of oocyte quality were adopted as objective measure to assess possible damage from cryopreservation. The study results indicate that the adoption of serum minimises cell damage induced by cryopreservation. Indeed, typical hallmarks of cryodamage in human oocytes, i.e. loss of cortical granules, zona pellucida hardening and above all vacuolization, were largely reduced in oocytes cryopreserved with solutions containing serum, especially if used a higher concentration. This suggest that oocyte cryopreservation still has significant margins of improvement that may derive also from composition of cryopreservation media.

The impact of sperm DNA fragmentation on ICSI outcome in cases of donated oocytes.

PURPOSE: The aim of this study is to evaluate the sperm DNA fragmentation index (DFI) in oocyte donation cycles and correlate it with the sperm parameters, the male characteristics, the embryo quality and the outcome of intracytoplasmic sperm injection (ICSI). METHODS: A total of 150 couples participating in an oocyte donation program were included in the study. Sperm samples were assessed by conventional sperm analysis. DFI was evaluated using the Halosperm kit, a sperm chromatin dispersion test (SCD). RESULTS: The relations between DNA damage and epidemiological male factors (age, height, weight), standard semen parameters (concentration, total and forward motility, and morphology), and embryological and clinical parameters (fertilization rate, total blastocyst number, number of good quality blastocyst, clinical pregnancy) were analyzed. DFI was positively correlated with advanced male age (r = 0.23, p < 0.05) and negatively correlated with total sperm and forward motility (r = - 0.29, r = - 0.27, respectively; p < 0.05). DFI was not significantly correlated with pregnancy outcome in oocyte donation cycles (r = - 0.05, p > 0.05). When good quality blastocysts were chosen, a trend toward the development of good quality embryos was detected in the presence of a low DFI (r = - 0.20, p = 0.08). CONCLUSIONS: DFI does not significantly affect the outcome of ICSI in oocyte donation cycles. Even in cases of advanced paternal age that a high DFI resulted sperm DNA fragmentation seems not to adversely affect the final outcome.