https://www.fertstert.org/article/S0015-0282(03)00402-3/pdf

Hyaluronic acid binding by human sperm indicates cellular maturity, viability, and unreacted acrosomal status.

The pesticide DDT [111-trichloro-22-bis(chlorodiphenyl) ethane] is 1 of the 12 persistent organic pollutants (POPs) under negotiation at the Stockholm Convention to restrict or ban their production and use because of their toxicity resistance to breakdown bioaccumulation and potential for being transported over long distances. DDT has estrogenic potential and the main metabolite pp-dichlorodiphenyl-dichloroethylene (pp-DDE) is a potent antiandrogen. In response to mounting evidence on the endocrine-disrupting influence of environmental chemicals on human health this epidemiological study was initiated to test the hypothesis that nonoccupational exposure to DDT affects male reproductive parameters. In a cross-sectional study healthy male subjects (n = 311) between 18 and 40 years (23 plus or minus 5) of age were recruited from 3 communities in an endemic malaria area in which DDT is sprayed annually. A semen analysis according to World Health Organization (WHO) standards was performed. The Hamilton Thorne Computer Assisted Sperm Analysis (CASA) system was simultaneously used to determine additional sperm motility parameters. Blood plasma samples were assayed for pp-DDT and metabolites as a measure of exposure. The exposure levels were expressed as lipid-adjusted pp-DDT and pp-DDE values. The mean pp-DDT and pp-DDE concentrations were 90.23 micro g/g (plus or minus 102.4) and 215.47 micro g/g (plus or minus 210.6) respectively. The multivariate linear regression analyses indicated that mean CASA motility was lower with a higher pp-DDE concentration (s = -0.02 P = .001) and the CASA parameter beat cross-frequency (BCF) was higher with a higher pp-DDT concentration (s = 0.01 P = .000). There was also a statistically significant positive association between percent sperm with cytoplasmic droplets and pp-DDT concentration (s = 0.0014 P = .014). The ejaculate volume (mean 1.9 plus or minus 1.33 mL) was lower than the normal range (=2.0 mL) according to WHO and a significant decrease with increasing pp-DDE values was seen for both square root-transformed volume (s = -0.0003; P = .024) and count (s = -0.003; P = .04). Although there were no associations between either pp-DDT or pp-DDE concentrations and the rest of the seminal parameters the incidence of teratozoospermia (99%; normal sperm less than 15%) was high. Twenty-eight percent of the study group presented with oligozoospermia (less than 20 x 10/6 sperm/mL) which had a significant positive association with pp-DDE (odds ratio [OR] = 1.001 P = .03). There was a significant positive association between participants with asthenozoospermia (32%) and pp-DDT (OR 1.003 P = .006) and pp-DDE (OR 1.001 P = .02). The results imply that nonoccupational exposure to DDT is associated with impaired seminal parameters in men. The high exposure levels of pp-DDT and pp-DDE are of concern because these levels could have far-reaching implications for reproductive and general health. (authors)

https://imedea.uib-csic.es/master/cambioglobal/Modulo_IV_cod101610/articulos/aneck-hahnetal2007%20j%20and.pdf

Impaired semen quality associated with environmental DDT exposure in young men living in a malaria area in the Limpopo Province, South Africa.

The mechanisms responsible for producing abnormal spermatozoa in the ejaculate are relatively unknown. Numerous studies have now shown the presence of nuclear DNA strand breaks in human ejaculated spermatozoa and the abnormal persistence of apoptotic marker proteins. The reason why human spermatozoa, in particular from men with abnormal semen parameters, possess these abnormalities is still not clear. Two processes that have been linked to the presence of nuclear DNA strand breaks in spermatozoa are anomalies in apoptosis during spermatogenesis or problems in the replacement of histones with protamines during spermiogenesis. Understanding the mechanisms responsible for producing abnormal spermatozoa in the human will improve knowledge about certain causes of male infertility.

https://www.rbmojournal.com/article/S1472-6483(10)61886-X/pdf

Abnormal spermatozoa in the ejaculate: abortive apoptosis and faulty nuclear remodelling during spermatogenesis

The mechanisms responsible for producing abnormal spermatozoa in the ejaculate are relatively unknown. Numerous studies have now shown the presence of nuclear DNA strand breaks in human ejaculated spermatozoa and the abnormal persistence of apoptotic marker proteins. The reason why human spermatozoa, in particular from men with abnormal semen parameters, possess these abnormalities is still not clear. Two processes that have been linked to the presence of nuclear DNA strand breaks in spermatozoa are anomalies in apoptosis during spermatogenesis or problems in the replacement of histones with protamines during spermiogenesis. Understanding the mechanisms responsible for producing abnormal spermatozoa in the human will improve knowledge about certain causes of male infertility.pathophysiological/clinical knowledge is gained.

Abnormal spermatozoa in the ejaculate: abortive apoptosis and faulty nuclear remodelling during

The testis-expressed chaperone protein, HspA2 (previously creatine kinase M isoform) was established as a measure of human sperm cellular maturity, function and fertility. The presence of HspA2 in the synaptonemal complex is likely to link low HspA2 expression and increased frequency of chromosomal aneuploidies in arrested-maturity spermatozoa. A relationship also exists between HspA2 expression in elongating spermatids and the associated spermatogenetic events, including plasma membrane remodelling and the formation of zona pellucida and hyaluronic acid (HA) binding sites. The HA receptor of mature spermatozoa, when coupled with HA-coated slides and/or Petri dishes, allows visual observation of sperm–HA binding, providing a basis for sperm maturity testing, a major improvement in semen evaluation, and selection of mature spermatozoa for intracytoplasmic sperm injection (ICSI). Thus, in HA-selected spermatozoa the frequency of chromosomal disomy and diploidy is reduced 4- to 6-fold compared with semen sperm fractions. This reduction is similar to the increase in numerical chromosomal aberrations in ICSI children. Combined studies of sperm shape and chromosome probes demonstrated that sperm morphology does not aid selection of haploid spermatozoa. The HA-mediated sperm selection is a novel and efficient technique that may alleviate potential problems related to ICSI fertilization with visually selected spermatozoa.

https://www.rbmojournal.com/article/S1472-6483(10)61060-7/pdf

Fertility testing and ICSI sperm selection by hyaluronic acid binding: clinical and genetic aspects.

As part of our studies on sperm maturity and function, we examined the head, midpiece and tail of human spermatozoa using computerized morphometry in order to determine which regions reflect the differences between mature spermatozoa and spermatozoa of diminished cellular maturity. We studied 20 men, who were divided into two groups based on their lower (LCKM: 14.6 K 7.0%, n J 8) and higher sperm creatine kinase (CK-M) isoform ratios (HCKM: 48.0 K 4.3%, n J 12) in the initial semen. Using a sequential centrifugation method which relies on the lower density of immature spermatozoa with retained extra cytoplasm, we prepared three sperm fractions with progressively declining maturity, as confirmed with CK-M isoform ratio measurements. Following the sequential fractionation, we affixed the spermatozoa to glass slides, stained the midpiece and the sperm contour, and photographed 25 spermatozoa in each of the 60 fractions (1509 spermatozoa in all). The spermatozoa were then individually digitized on the Image-1 system, and the dimensions of the head, midpiece, and tail were determined. While the data showed significant differences in the midpiece and tail dimensions between the mature and diminished-maturity sperm fractions, the head dimensions were similar and did not reflect sperm maturity. We postulated that the relationship between the biochemical markers of sperm maturity and sperm morphology is based on common spermiogenic events. The data support this idea. In immature spermatozoa in which cytoplasmic extrusion, CK-M isoform expression, and tail sprouting are all diminished, the retained extra cytoplasm in the midpiece and shorter tail length contribute to the morphological variations that we identified by morphometry and considered in sperm morphology. These morphometric features, in association with fluorochrome-coupled biochemical probes, can facilitate the identification of mature spermatozoa in computer-assisted semen analysis.

/pdf/morphometric-assessment-of-mature-and-diminished-maturity-1tlku9tdu8.pdf

Levent Senturk

Papers

Morphometric assessment of mature and diminished-maturity human spermatozoa: sperm regions that reflect differences in maturity