Search

Aberrant sperm protamination is linked to sperm dysmorphology and nuclear chromatin condensation. Yet, its effects on sperm cytoplasmic maturation remain largely unexplored. The relationships of protamines, sperm morphology, DNA damage, and cytoplasmic remodeling were illustrated in this study to provide fresh perspectives on the mechanisms of male infertility. A total of 205 infertile males were allocated into 5 groups according to the percentage of spermatozoa exhibiting abnormal morphology within their samples. Sperm concentration, motility, abnormal sperm morphology, cytoplasmic droplets (CDs), and excess residual cytoplasm (ERC) were analyzed according to the World Health Organization manual (2010). Sperm nuclear vacuoles (NVs) were determined by propidium iodide (PI) staining. Sperm protamine expressions (P1 and P2) were detected by western blot. DNA damage was measured by acridine orange test (AOT) to calculate the proportion of sperm with single-strand DNA breaks (SSBs). Our data showed that sperm concentration and motility in infertile males significantly decreased with the severity of abnormal sperm morphology (both P < 0.01). P1 level, P1/P2 ratio, and SSB rate increased with the severity of sperm dysmorphology, whilst the P2 level decreased (all P < 0.01). NVs, CDs, and ERC were more common in males with sperm dysmorphology and positively correlated with the SSB rate (all P < 0.01). The relationships between the SSB rate and the P1/P2 ratio were also significant (P < 0.01). Aberrant protamination may cause sperm dysmorphology and compromise male fertility by impairing sperm's nucleus and cytoplasm maturation, with the P1/P2 ratio potentially serving as a valuable indicator of sperm quality and male fertility.

Background: Although defects in sperm morphology and physiology lead to male infertility, in many instances, the exact disruption of molecular pathways in a given patient is often unknown. The glycolytic pathway is an essential process to supply energy in sperm cell motility. Enolase 4 (ENO4) is crucial for the glycolytic process, which provides the energy for sperm cells in motility. ENO4 is located in the sperm principal piece and is essential for the motility and organization of the sperm flagellum. In the present study, we characterized a family with asthenozoospermia and abnormal sperm morphology as a result of a variant in the enolase 4 (ENO4) gene. Methods: Computer‐assisted semen analysis, papanicolaou smear staining and scanning electron microscopy were used to examine sperm motility and morphology for semen analysis in patients. For genetic analysis, whole‐exome sequencing followed by Sanger sequencing was performed. Results: Two brothers in a consanguineous family were being clinically investigated for sperm motility and morphology issues. Genetic analysis by whole‐exome sequencing revealed a homozygous variant [c.293A>G, p.(Lys98Arg)] in the ENO4 gene that segregated with infertility in the family, shared by affected but not controls. Conclusions: In view of the association of asthenozoospermia and abnormal sperm morphology in Eno4 knockout mice, we consider this to be the first report describing the involvement of ENO4 gene in human male infertility. We also explore the possible involvement of another variant in explaining other phenotypic features in this family. [ABSTRACT FROM AUTHOR]

Logistic regression models, including variables of boar breed, age, serum, and seminal plasma elements, were used to identify the influencing factors of sperm motility and morphology in this study. Sperm motility degree was classified as grade 0: ≤85% and grade 1: >85%. Abnormal sperm morphology was classified as grade 0: ≤10%, grade 1: 10−20%, and grade 2: >20%. Element concentration of 385 boars was detected by inductively coupled plasma mass spectrometry. Results showed that boars with serum Cu ≥ 2.5 mg/L had lower sperm motility (odds ratio (OR): 0.496; 95% confidence interval (CI): 0.285−0.864) and higher abnormal sperm morphology (OR: 2.003; 95% CI: 1.189−3.376) than those with serum Cu ≤ 2.0 mg/L. Boars with serum Fe ≥ 1.5 mg/L had lower abnormal sperm morphology than those with serum Fe ≤ 1.0 mg/L (OR: 0.463; 95% CI: 0.255−0.842). The presence of Pb in seminal plasma increased abnormal sperm morphology. The probability of abnormal sperm morphology >20% from boars with seminal plasma Pb increased with a range of 5.78−15.30% than that from boars without seminal plasma Pb among three breeds. In conclusion, serum Cu excess, serum Fe deficiency, and seminal plasma Pb are risk factors for poor semen quality in boars.

The evaluation of strict morphology for predicting successful pregnancy has been controversial, nevertheless remains an essential component of semen analysis. Patients with teratozoospermia (abnormal strict morphology) have traditionally been counseled to undergo assisted reproduction. However, recent studies suggest that patients with abnormal sperm morphology alone should not be precluded from attempting natural conception before undergoing assisted reproduction. The goal of this review is to provide an update on the evaluation of sperm morphology for prognosis in assisted reproductive techniques such as intrauterine insemination and in vitro fertilization with or without intracytoplasmic sperm injection. Additionally, we propose a logical approach to the evaluation of a patient with teratozoospermia seeking fertility treatment. [ABSTRACT FROM AUTHOR]

Abstract: The objective was to investigate expression patterns of proteins in pyriform sperm, a common morphological abnormality in bull sperm. Ejaculates were collected from sexually mature Holstein bulls (n=3) twice weekly for 10weeks (pre-thermal insult samples). Testicular temperature was elevated in all bulls by scrotal insulation for 72 consecutive hours during week 2. Total sperm proteins were extracted from pre- and post-thermal insult sperm samples and subjected to two-dimensional gel electrophoresis. Among the protein spots detected, 131 spots were significantly expressed (False Detection Rate <0.01) with ≥2 fold changes between normal and pyriform sperm. Among them, 25 spots with ≥4 fold difference in expression patterns were identified using liquid chromatography coupled with tandem mass spectrometry (LC–MS/MS). Expression of several proteins involved in sperm capacitation, sperm–egg interaction and sperm cytoskeletal structure was decreased in pyriform sperm, whereas proteins regulating antioxidant activity, apoptosis and metabolic activity were increased. Contents of reactive oxygen species and ubiquitinated proteins were higher in pyriform sperm. In addition to understanding the molecular basis of functional deficiencies in sperm with specific morphological abnormalities, comparing normal versus morphologically abnormal sperm appeared to be a suitable experimental model for identifying important sperm functional proteins. Biological significance: To our knowledge, this study is the first report on differential expression of proteins in pyriform bovine sperm versus morphologically normal sperm. We report that expression of several proteins involved in sperm capacitation, sperm–egg interaction and sperm cytoskeletal structure was decreased in pyriform sperm, whereas proteins which regulate antioxidant activity, apoptosis and metabolic activity were increased. Contents of reactive oxygen species and ubiquitinated proteins were higher in pyriform sperm. In addition to understanding the molecular basis of functional deficiencies in sperm with specific morphological abnormalities, our results suggest that comparing normal versus morphologically abnormal sperm appeared to be a suitable experimental model for identifying important sperm functional proteins. [Copyright &y& Elsevier]

Abstract: The study was conducted to evaluate the effects of scrotal insulation on semen samples collected from bulls on embryonic development after IVF. Semen samples were obtained and cryopreserved from four Holstein bulls before and after a scrotal insulation period of 48h (Day 0). Three types of samples were used for IVF: (1) semen from the test bulls collected 5 d prior to scrotal insulation (pre-insult); (2) semen from Day 13 (2-week post-insult; 2-week PI); and (3) semen from Day 20 (3-week PI). After 18h of sperm–oocyte co-incubation, the zygotes were cultured for 8 d when a developmental score (0=degenerate, 1=2-cell embryo through 5=blastocyst) was assigned to each embryo. The post-thaw morphological evaluation of sperm samples revealed a decrease (P &#60;0.01) in the percentages of normal spermatozoa in the 3-week PI samples in comparison with the pre-insult samples for Bulls I and III (74–22.3% and 67.7–0.5 %, respectively). The percentage of vacuolated spermatozoa increased significantly for Bull II. The cleavage and blastocyst formation rates and embryo development scores were affected (P &#60;0.01) by the interaction of bull by sample collection time. For Bulls I and III (severe responders) the scrotal insulation effects persisted from the time of cleavage through blastocyst formation. In contrast, the cleavage and blastocyst formation rates for Bulls II and IV were unaffected, despite high percentages of vacuolated spermatozoa present in the post-insult samples for Bull II. In conclusion, the use of scrotal insulation to elevate scrotal temperature was an effective method to obtain semen samples with high percentages of abnormal spermatozoa. The decrease in embryonic development after IVF when using spermatozoa with morphological abnormalities seemed to be multifaceted and related to changes in head morphology. [Copyright &y& Elsevier]

Abstract: Although several reports have demonstrated the acutely toxic and genotoxic effects of landfill leachates in microbial organisms, plants and aquatic animals, the effects of pollutants present in these leachates have not been clarified yet in terrestrial animals. This study mainly aimed to evaluate a potential genetic effect of raw and simulated leachates from Orita-Aperin and Oworonsoki landfills in south-west Nigeria by use of the murine sperm-head abnormality test. These landfills neither have a synthetic membrane liner at the bottom, nor a natural layer of compacted soil with the desired hydraulic conductivity, nor a run-off control system. As a result, the leachates produced are discharged into the environment. Samples designated as Orita-Aperin Raw Leachate (OARL), Orita-Aperin Simulated Leachate (OASL), Oworonsoki Raw Leachate (OWRL) and Oworonsoki Simulated Leachate (OWSL) were analyzed in the sperm-head abnormality test at concentrations (v/v) of 1%, 2.5%, 5%, 10% and 25%. Mice were given 0.5ml sample per day for five consecutive days by intraperitoneal injection. Each dose group comprised seven mice, and a 5-week exposure period was utilized. The data show that the test mixtures induced a dose-dependent, statistically significant increase (P &#60;0.05) in the number of sperm with abnormal morphology. Physico-chemical analysis of the test samples shows that they contained constituents that are capable of inducing mutation in biologic system. The interaction of some of these constituents with the genetic material in the differentiating cells during spermatogenesis may be responsible for these observations. This is relevant in environmental waste management, and for the assessment of the hazardous effects of the chemicals in landfill leachates. [Copyright &y& Elsevier]

Simple Summary: Reduced sperm motility and morphological abnormalities have significant negative impacts on conception rates in sows and are important indexes of semen. The identification of factors that influence sperm motility and morphology will improve boar fertility in commercial herds. On the basis of analysis of 5042 ejaculates from 385 boars using a logistic regression model, we found that serum Cu excess, serum Fe deficiency, and Pb presence in seminal plasma were risk factors for poor semen quality in boars. More importantly, the presence of seminal plasma Pb had more serious effect on the probability of abnormal sperm morphology than serum Cu excess and serum Fe deficiency. In addition, Yorkshire and Landrace boars had higher sperm motility and lower abnormal sperm morphology than Duroc boars. The difference in serum and seminal plasma elements among boars with different semen qualities may become a guide for regulating these elements used in boar diet. The highly predictive values of serum Cu, Fe, and seminal plasma Pb could be used in the future as an additional tool in semen quality evaluation. Logistic regression models, including variables of boar breed, age, serum, and seminal plasma elements, were used to identify the influencing factors of sperm motility and morphology in this study. Sperm motility degree was classified as grade 0: ≤85% and grade 1: >85%. Abnormal sperm morphology was classified as grade 0: ≤10%, grade 1: 10–20%, and grade 2: >20%. Element concentration of 385 boars was detected by inductively coupled plasma mass spectrometry. Results showed that boars with serum Cu ≥ 2.5 mg/L had lower sperm motility (odds ratio (OR): 0.496; 95% confidence interval (CI): 0.285–0.864) and higher abnormal sperm morphology (OR: 2.003; 95% CI: 1.189–3.376) than those with serum Cu ≤ 2.0 mg/L. Boars with serum Fe ≥ 1.5 mg/L had lower abnormal sperm morphology than those with serum Fe ≤ 1.0 mg/L (OR: 0.463; 95% CI: 0.255–0.842). The presence of Pb in seminal plasma increased abnormal sperm morphology. The probability of abnormal sperm morphology >20% from boars with seminal plasma Pb increased with a range of 5.78–15.30% than that from boars without seminal plasma Pb among three breeds. In conclusion, serum Cu excess, serum Fe deficiency, and seminal plasma Pb are risk factors for poor semen quality in boars. [ABSTRACT FROM AUTHOR]

Mixture of xenobiotics in Olusosun landfill leachates (OSL) induced somatic and germ cell genotoxicity in eukaryotic cells. However, whether the DNA-damaged germ cells can increase reproductive failure, embryotoxicity and/or teratogenicity during fertilization remained unclear. The study herein investigated reproductive toxicity and embryotoxic effects of OSL in mice using abnormal sperm morphology and dominant lethal mutation assays. Six mice per group were exposed to 0.5 mL of 5, 10, 25, and 50% OSL (v/v, leachate/distilled water) for 5 consecutive days. Similar treatment was giving to distilled water and cyclophosphamide (20 mg/kg body weight), as negative and positive control groups, respectively. At 35 day post-treatment, the mice were sacrificed and examined for cauda epididymal abnormal sperm morphology, testicular weight change and histopathological lesions. Male mice were mated to untreated nulliparous females (1 treated male per 2 untreated females) until vaginal plugs were observed. Pregnant females were sacrificed on 14th day post-mating and uterine content examined for number of implants per female, resorptions, and live and dead fetuses. OSL significantly increased teratozoospermia by 31.02% with amorphous sperm head having the highest frequency and sperm with two heads, the least. Histology of the testes revealed congestion of the interstitial blood vessels, spermatid retention and disorganization of the germinal epithelium from the basal compartment. OSL insignificantly increased absolute and relative testes weights but reduced body weight of exposed mice. There was insignificant induction of dominant lethal mutation, although low fertility was observed in the treated mice. The analyzed physico-chemical parameters and heavy metals/metalloids in OSL were higher than permissible limits. The metals, physico-chemical parameters and other unanalyzed substances in OSL induced abnormal sperm morphology, altered testes pathology, but did not significantly induce dominant lethal mutation in mice. Constituents of OSL are toxic to the male reproductive organs in mice and suggests harmful impact on public health. Indiscriminate disposal of solid wastes in the environment should be prevented.