Progressive Decline In Motility Research Articles

Systematic Analysis of Breed, Methodological, and Geographical Impact on Equine Sperm Progressive Motility.

Simple SummarySemen quality is an important indicator of reproductive health and fertility. With adverse temporal trends in human semen quality over the past 50 years paralleled in male animals, there is increasing concern for the causes and implications of perturbed male reproductive health. The evaluation of equine progressive motility (PM), a parameter closely associated with fertility, provides information on the fertilising capacity of equine ejaculate and current reproductive health of the equine stallion. Using systematic analysis, recent trends in equine PM were determined from 696 estimates from 280 individual studies. Temporal trends indicate equine PM has not significantly changed between the years 1990 and 2018. Significant breed, methodological, and geographical variations observed in equine PM may considerably influence actual and reported stallion fertility potential. Information on stallion PM meaningfully contributes to the wider literature on semen quality and provides avenues for future stallion fertility research. This systematic analysis presents the wider challenges associated with semen quality assessment, particularly within the equine sector, and provides recommendations to promote consistency across industry and research.Over the past five decades, there has been increasing evidence to indicate global declines in human semen quality. Parallel adverse trends measured in male animals indicate a potential environmental aetiology. This study evaluated the progressive motility (PM) of stallion ejaculate through a systematic review and meta-analysis. A total of 696 estimates of equine PM from 280 studies, which collected semen samples between the years 1990 and 2018, were collated for meta-analysis. The method of motility analysis, breed, season of collection, and geographical location were extracted. Simple linear regression determined temporal trends in stallion PM. Studies using microscopy estimated PM to be significantly greater compared to computer-automated methods (p ≤ 0.001). For Arabian breeds, PM was consistently higher than other breeds. Over time, there was a significant decline in PM for studies from Europe (n = 267) but a significant increase for studies from North America (n = 259). Temporal trends indicate the fertilising capacity of equine ejaculate has remained consistently high in the last three decades. That being so, variations observed suggest methodological, geographical, and individual stallion differences may significantly influence actual and reported stallion fertility potential.

Mutation in histone deacetylase HDA-3 leads to shortened locomotor healthspan in Caenorhabditis elegans.

Some genes are essential for survival, while other genes play modulatory roles on health and survival. Genes that play modulatory roles may promote an organism’s survival and health by fine-tuning physiological processes. An unbiased search for genes that alter an organism’s ability to maintain aspects of health may uncover modulators of lifespan and healthspan. From an unbiased screen for Caenorhabditis elegans mutants that show a progressive decline in motility, we aimed to identify genes that play a modulatory role in maintenance of locomotor healthspan. Here we report the involvement of hda-3, encoding a class I histone deacetylase, as a genetic factor that contributes in the maintenance of general health and locomotion in C. elegans. We identified a missense mutation in HDA-3 as the causative mutation in one of the isolated strains that show a progressive decline in maximum velocity and travel distance. From transcriptome analysis, we found a cluster of genes on Chromosome II carrying BATH domains that were downregulated by hda-3. Furthermore, downregulation of individual bath genes leads to significant decline in motility. Our study identifies genetic factors that modulate the maintenance of locomotor healthspan and may reveal potential targets for delaying age-related locomotor decline.

Decline of semen quality during IVF is not associated with subjective male stress

The aim of the present study was to assess if semen quality declines during in vitro fertilization (IVF) and whether or not this phenomenon is triggered by chronic male stress. In order to test this hypothesis, we first investigated a retrospective cohort of 155 male IVF patients (testing cohort). Subsequently, we started a prospective cohort study in men undergoing their first IVF and assessed semen quality and subjective male chronic stress using a validated tool, i.e. the Fertility Problem Inventory (FPI) questionnaire. The association between stress and sperm quality decline measured 4–6 weeks before the start of IVF (T1) and at the day of oocyte retrieval (T2) was the primary outcome. Live birth rate, first trimester abortion and rate of poor responders were secondary outcomes. In the testing cohort, mean progressive motility, but not mean sperm density significantly declined. There were 78/154 (51%) men who showed a decline in semen density and 50/154 (32%) men who showed a decline in progressive motility. In the validation cohort, progressive motility declined, whereas, sperm density increased from T1 to T2. Of 78 men, 27 men had increased stress (FPI-score > 146). Sperm density and progressive motility were not significantly different in men with and without stress. However, in the presence of male stress, couples had a higher rate of poor responders, miscarriages and a lower rate of live births. Subjective stress is not associated with a decline in semen quality observed during IVF but may be associated with adverse pregnancy outcome.

Supplementation of biotin to sperm preparation medium increases the motility and longevity in cryopreserved human spermatozoa

To study the effect of supplementing biotin to sperm preparation medium on the motility of frozen-thawed spermatozoa. Semen samples of men attending the University infertility clinic (n = 105) were cryopreserved using glycerol-egg yolk-citrate buffered cryoprotective medium in liquid nitrogen. After a period of two weeks, the semen samples were thawed and the motile spermatozoa were extracted by swim-up technique using Earle's balanced salt solution (EBSS) medium supplemented with either biotin (10 nM) or pentoxifylline (1 mM). The post-wash motility was observed up to 4 h after incubation. Both biotin and pentoxifylline supplementation resulted in significant increase in total motility (p < 0.05), progressive motility (p < 0.001) and rapid progressive motility (p < 0.05 v/s biotin and p < 0.01 v/s pentoxifylline) compared to the control at 1 h post-incubation period. Significantly higher percentage of total (p < 0.01, p < 0.05 in biotin and pentoxifylline respectively), progressive (p < 0.001) and rapid progressive motilities (p < 0.01) were observed in these two groups even at 2 h compared to the control. In the control group at 4 h after incubation, ~11% decline in total motility and ~8% decline in progressive motility was observed. However, in both biotin and pentoxifylline group the motility was significantly higher than control (p < 0.001). No significant difference in the motility was observed between biotin and pentoxifylline groups at any of the time intervals studied. Biotin can enhance the sperm motility and prolong the survival of frozen-thawed semen samples which may have potential benefit in assisted reproductive technology field.

Sperm motility stimulation and preservation with various concentrations of follicular fluid

The purpose of this study is to evaluate the optimal concentrations of follicular fluid (FF) for sperm motility stimulation and preservation. Thirty normal semen samples and FF from women in an in vitro fertilization programme were used in an experiment. The semen was processed and incubated in Earle culture media with 20, 50, 80, and 100% FF (v/v) with controls. Sperm motility was evaluated and followed up for 48 h. FF could stimulate progressive sperm motility at all concentrations and last for at least 12 h. However, at more than 50% v/v of FF, sperm demonstrated a rapid decline in progressive motility after 12 h of incubation compared to other concentrations and the control group. FF can stimulate the sperm motility properly at not more than 50% (v/v) concentration.

The rapid detection of cytotoxicity using a modified human sperm survival assay.

Sperm were cultured at room temperature in seminal plasma, in the presence or absence of a test item or solution. Progressive motility of the sperm was measured using a Sperm Quality Analyser IIB. A progressive decline in motility of sperm was seen under control conditions from 0 hr to 24 hrs. Culture medium did not cause a significant decline in sperm survival index during the first 6 hrs of culture but did after 24 hrs. A dose dependent reduction in sperm survival index was then seen with formaldehyde. Powder-free rubber gloves proved extremely toxic unlike the associated rubber plunger of a non-pyrogenic syringe. It is concluded that the use of unwashed human sperm in survival studies allows detection of toxicity within 6 hrs, a time much less than conventional methods using washed human sperm.

Detection of lipid peroxidation in equine spermatozoa based upon the lipophilic fluorescent dye C1l-BODIPY581/591.

The lipophilic fluorescent probe, 4,4-difluoro-5-(4-phenyl-1 ,3-butadienyl)-4-bora-3a,4a-diaza-s-indacene-3-undecanoic acid (C11-BODIPY581/591) was used to evaluate changes in lipid peroxidation in equine spermatozoa during both short-term exposure to ferrous sulfate and sodium ascorbate in the presence of cumene hydroperoxide as well as during storage of spermatozoa at 5 degrees C for 48 hours. Peroxidation of C11-BODIPY581/591 was accompanied by a shift in fluorescence from red to green, and the relative amount of nonoxidized probe was determined as the ratio of red:(red + green) fluorescence as detected by either fluorescence microplate reader or by flow cytometry. The addition of Fe2SO4 (0 to 0.5 mM), low concentrations of sodium ascorbate, and the addition of cumene hydroperoxide increased peroxidation of C11-BODIPY581/591. The addition of high concentrations (10 or 20 mM) of sodium ascorbate or alpha-tocopherol reduced peroxidation of C11-BODIPY581/591 during short-term incubations. During storage at 5 degrees C in a skim milk-based extender, equine spermatozoa demonstrated a progressive decline in motility and a small but significant increase in lipid peroxidation based upon ratiometric analysis of C11-BODIPY581/591. The addition of Fe2SO4 increased lipid peroxidation in cooled spermatozoa in a dose-dependent fashion and decreased sperm motility. The addition of alpha-tocopherol, however, did not reduce lipid peroxidation during cooled semen storage. These data demonstrate that the lipophilic fluorescent probe C11-BODIPY581/591 is a useful measurement of lipid peroxidation in equine spermatozoa and that there is an increase in lipid peroxidation during cooled storage of equine spermatozoa that is increased in the presence of ferrous promoters.

Spermatozoa selected by a discontinuous Percoll density gradient exhibit better motion characteristics, more hyperactivation, and longer survival than direct swim-upt

To determine if a discontinuous Percoll density gradient selects spermatozoa with different motion characteristics than direct swim-up. Controlled prospective study of the effect of two preparation techniques on spermatozoa from normal semen samples using computer-aided sperm analysis (CASA). The Fertility laboratory, Queen Charlotte's Hospital, London, United Kingdom. Eighteen male patients. Semen samples were divided into two equal parts. The first part was prepared by a direct swim-up whereas the other half was subjected to a three-layer discontinuous Percoll density gradient centrifugation. The separated samples were then examined at 30 minutes and 3, 6, and 24 hours by CASA. Although swim-up selected a higher proportion of motile spermatozoa, Percoll produced a greater yield of motile cells. Straight line velocity was similar for both methods throughout study. In contrast, spermatozoa isolated by Percoll exhibited a significantly higher curvilinear velocity and amplitude of lateral head displacement, which lasted for > or = 6 hours. These changes were accompanied by a significant reduction in linearity of progression. The most dramatic effect of Percoll was to produce significantly greater numbers of spermatozoa expressing hyperactivation. After both swim-up and Percoll there was a decline in progressive motility over the 24 hours, although this was only significant for swim-up. In normal semen, a discontinuous Percoll density gradient selects spermatozoa with better motion characteristics, more hyperactivation, and improved longevity compared with direct swim-up. In view of the relationship between sperm motion characteristics and fertilizing ability, we conclude that the three-layer discontinuous Percoll density gradient be adopted as the preferred method for the preparation of spermatozoa for assisted reproduction.

MEMBRANE-STABILIZING AND CALCIUM-BLOCKING AGENTS AFFECTARBACIASPERM MOTILITY

The speed and duration of progressive motility of Arbacia sperm cells depend on the calcium content of the suspension medium. Suspended in filtered sea water (FSW) the spermatozoa undergo a progressive decline in motility (after an initial burst of activity) and cease forward movement within 30-40 min. When sperm are diluted in chemically defined artificial sea water (MBL-ASW), motility rose to about 160% of the control rate in 30 min and then gradually returned to the initial control level where it persisted for at least 40 min more. Procaine, propranolol, ouabain, and quinidine, tested singly or in combination, affected sperm motility in both time- and concentration-dependent fashion.Procaine at 10 and 100 µM/l in MBL-ASW caused more than a doubling in motility over the control rate, while in FSW both these concentrations were inhibitory. In FSW, quinidine had relatively little effect, while propranolol was slightly stimulatory at 10-6M and inhibitory at 0.1 and 1.0 x 10-3M. In combination, propranolol and quinidine can cause a sharp rise in motility. Ouabain increased motility dramatically in MBL-ASW suspensions. The effects of some of the drugs depend on the ability to displace calcium from binding sites in sperm cell membranes; ouabain appears to interface with Ca efflux.

Freezing Bovine Semen. III. Effect of Freezing Rate on Bovine Spermatozoa Frozen and Stored at −79° C1,2

Summary These experiments show the effect of various freezing rates on the decreases in the percentages of motile spermatozoa during freezing and storage at −79° C. Spermatozoa diluted in heated fresh skimmilk showed a progressive decline in motility, irrespective of freezing rate when ampules were removed at −10, −15, −20, −35, −50, and −79° C. Greatest losses in motility with 12 freezing rates occurred between −10 and −35° C. Samples thawed immediately after reaching −79° C. showed the highest motility when a rate of 10° C. per minute from −15 to −50° C. was used. However, following storage for ten days at −79° C. there was a smaller loss of motile spermatozoa with a rate of 5° C. per minute. Very rapid freezing (70° C. per minute) was extremely detrimental; 75% of the total motile spermatozoa present before freezing were lost during freezing and storage for ten days, as compared to only 40% with a freezing rate of 10° C. per minute from −15° C. Similar, but less pronounced, harmful effects were observed when semen diluted in whole milk and yolk-citrate was frozen rapidly. In a storage trial for 0, 2, 4, 8, 16, and 32 wk., the optimum freezing rate for semen diluted in fresh skimmilk or homogenized milk was 1° C. per minute from +5 to −15° C., 5° C. per minute from −15 to −50° C., and rapidly (approximately 20° C. per minute) from −50 to −79° C. The optimum rate for semen diluted in 1:4 egg yolk-citrate was 3° C. per minute from +5 to −15° C. and 5 or 10° C. per minute from −15 to −50° C. The greatest decline in spermatozoan survival occurred during the first 4 wk., regardless of diluents or freezing rates.