[Influence of paternal age]. / Influence de l'âge paternel.

Father's age increase miscarriage, malformation, risk of autism, schizophrenia, and bipolar troubles in children.

Male infertility risk factors in a French military population.

We investigated infertility risk factors by conducting a population-based case-control study in the military population of the French town of Brest. Sixty couples who had sought medical advice for infertility of more than 12 months duration (cases) were compared with 165 couples who had had a child (controls). All the men in these couples had been employed by the military. The infertility risk factors studied were male and female medical factors, occupational and environmental exposures. We obtained age-adjusted odds ratios of 7.4 [95% confidence interval (CI): 1.4--39.5] for testis surgery, and 13.0 for varicocele (95% CI: 1.4--120.3) in men. In logistic regression, the age-adjusted odds ratio for men who had worked in a nuclear submarine was found to be 2.0 (95% CI: 1.0--3.7), and that for heat exposure was 4.5 (95% CI: 1.9--10.6). One limitation of this study is the lack of exposure measurements, especially for potential exposure to nuclear radiation (type of reactor used in nuclear-powered submarines, inability to obtain personal dosimeters worn by military personnel working in nuclear submarines). In conclusion, this study suggests that in this military population, having worked as a submariner in a nuclear-powered submarine, and having worked in very hot conditions, should be considered as risk factors for infertility.

[From in vitro fertilization to embryo transfers: evaluation of ten years of reproductive medical assistance in the private sector in France]. / De la FIV à l'ICSI: bilan de dix ans d'activité d'assistance médicale à la procréation (AMP) en secteur privé en France.

The activity of the private-run French AMP centers was analyzed through a retrospective study. The results were given in Toulouse in December 1995. IVF: 50% of activity in France are done in private centers. From 1983 to 1995, 71,974 oocyte retrievals allowing 53,370 embryo transfers were realized and 11,721 pregnancies occurred with 11,088 healthy babies born. ICSI: from 1992 to 1995 3,399 embryo transfers were done. The segmentation rate is 48%. The evolution of the 886 pregnancies thus obtained and the results of the foetal karyotype are detailed in the study. The other assisted reproductive technics (embryo freezing, oocyte donation) are undertaken in the private sector. The results can be found herewith.

Impairment of testicular endocrine function after lead intoxication in the adult rat.

To clarify the mechanism of the action of lead on male reproductive function, adult male rats were injected intraperitoneally (i.p.) with lead acetate (8 mg/kg/day of lead), 5 days a week for 35 days. Despite this high dose, germ cells and Sertoli cells did not appear to be major targets of lead. However, lead determination in the reproductive organs showed that the accessory sex glands are such a target. Epididymal function was unchanged. In lead-exposed rats, plasma and testicular testosterone dropped by about 80%, but plasma luteinizing hormone (LH) only dropped by 32%. After luteinizing hormone releasing hormone (LHRH) stimulation of the pituitary, the plasma LH level reached the control one, but plasma testosterone remained significantly reduced by 37%. The sharp decrease in the testosterone:LH ratio in lead-exposed rats, combined with the significant reduction of intertubular tissue volume in the testes, indicate impaired Leydig cell function.

[Spermatogenesis protection: myth or reality?]. / Protection de la spermatogenèse: mythe ou réalité?

Cytotoxic agents used in various therapies (anticancer treatments in particular) are known to be very deleterious to male fertility. In these situations, both quantitative (oligo and azoospermia) and qualitative alterations of the male reproductive system occur. What are the various possibilities to protect male reproduction? Sperm cryo-storage, prior to the beginning of chemotherapy and/or radiotherapy, is one possibility. However this possibility can only be offered to a relatively limited number of patients, due to the fact that the disease itself often causes gonadal abnormalities. Another possibility is the substitution of the most cytotoxic drugs by less deleterious agents, as well as, the reduction of the doses used in the therapeutic regimens. Progress in this field however remains very slow. Therefore, the use of various protective agents appears to be necessary. Of all the agents so far tested (anti-oxidants, GnRH analogs, FSH, steroids), the combination of medroxyprogesterone acetate and testosterone (MPA+T) is the one which has been the most studied both in men (contraception) and in rodents (contraception and protection). From a series of experiments using MPA+T in male rats, it appears that both qualitative and quantitative protection of fertility can be achieved against chemo- and radiotherapy. Progress in this field should be the prelude of clinical trials. This transfer from animals to men, should result as one of the activities of a pluri-disciplinary group supported by INSERM and entitled "Prosperm". The dialogue established in this group between researchers and physicians offers new perspectives in the domain of protection of spermatogenesis, at a time when this is most needed.(ABSTRACT TRUNCATED AT 250 WORDS)

[Spermatogenesis protection: myth or reality?]. / Protection de la spermatogenese: mythe ou realite?

PIP: The male reproductive system is especially sensitive to the deleterious effects of many natural environmental agents, the workplace, and medical agents. Immunosuppressants and anticancer agents, which improve the prognosis of survival or the quality of life of patients, induce temporary sterility in all treated patients and complete sterility in 50% of treated patients. These agents affect spermatogenesis. Quantitative effects include oligo- and azoospermia. Qualitative effects involve spermatozoa changes, which inhibit implantation and their ability to fertilize the ovum and adversely affect embryonic development. Research is and has been underway to identify possible ways to preserve spermatogenesis. The Centers for the Study and Conservation of Human Sperm (CECOS) in France receives sperm every year from many men with cancer, especially Hodgkin's disease or testicular cancer, who wish CECOS to preserve their sperm through cryopreservation before they undergo chemotherapy or radiotherapy. Using less deleterious agents instead of cytotoxic drugs is a possible means to protect spermatogenesis. Agents which have been tested include antioxidants, gonadotropin-releasing hormone analogs, follicle stimulating hormone, and steroids. Of these agents, medroxyprogesterone acetate and testosterone together (MPA + T) have been examined the most in rats (contraception and protection) and in men (contraception). The rat studies show that MPA + T can indeed protect spermatogenesis. Clinical trials in men are needed to support these findings. INSERM supports a multidisciplinary group examining spermatogenesis preservation called Prosperm, which will likely be the impetus for the start-up of such clinical trials. Prosperm members include researchers and physicians who network to keep each other up-to-date on spermatogenesis protection. Their collaboration is especially needed, since recent epidemiological studies indicate that diverse environment factors adversely affect spermatogenesis.^ieng

Germ cell control of testin production is inverse to that of other Sertoli cell products.

Recent studies have shown that germ cells can regulate testins, two newly identified Sertoli cell proteins that are associated with junctional complexes. To investigate this possibility, several parameters of Sertoli cell function were investigated over 2-120 days post exposure of the rat testes to x-rays (3 Grays). The irradiation-induced loss of spermatogonia resulted in a maturation-depletion process progressively affecting all germ cell classes. Testis weight began to decrease when the most numerous germ cell type (spermatids) began to decline. A complete or near complete recovery of spermatogenesis and of the testis weight had occurred by day 120 post irradiation. There was no significant change in FSH, epididymal androgen-binding protein, and tubule fluid levels during the first weeks after irradiation, when the seminiferious epithelium was depleted of spermatogonia and germ cells up to early spermatids. In contrast, when the number of the more mature forms of spermatids declined (between day 21 and 54), FSH rose and androgen-binding protein as well as fluid production declined. The subsequent recovery of these parameters was also highly correlated with the number of late spermatids. By contrast, testicular testin contents reacted to the depletion of germ cells with a biphasic increase; a doubling occurred when spermatogonia, spermatocytes, and early spermatids were absent (days 4-28), and a 7-fold rise occurred by day 37 when the number of late spermatids had decreased by 50%. By day 54, when the sperm counts had reached a nadir, testin contents had returned to levels corresponding to about four times the control levels; they progressively recovered thereafter. These observations support the postulate that germ cells negatively regulate testins. This possibility was investigated with in vitro experiments showing that addition of germ cell-conditioned medium to Sertoli cell monolayers inhibited testin secretion in a dose-dependent manner. In conclusion this study; 1) highlights the complex interplay between the various germ cell classes in the control of the Sertoli cell function in the adult testis; 2) establishes that germ cell effects may be opposite on different Sertoli cell products; 3) demonstrates that several classes of germ cells negatively control testicular testin contents; and 4) emphasizes the particular role of late spermatids in Sertoli cell regulation.

[Protection of male fertility during anticancer treatment: animal experiments]. / Protection de la fertilité mâle lors des traitements anticancéreux: l'expérience animale.

One of the best known iatrogenic effects of anticancer treatments is the sterility of young patients with a good prognosis, hence the necessity to develop a protocol enabling us to preserve male reproductive function. This review of the literature summarises the various approaches investigated in order to obtain protection of spermatogenesis prior to radiotherapy and/or chemotherapy. Most of these pathways involve hormone therapy based on regulation of the hypothalamo-hypophyso-testicular axis. Animal models are generally used in these experiments. The various applications in man are described and discussed.

Human spermatozoa selection in improved discontinuous Percoll gradients.

OBJECTIVE: Improve the technique of human spermatozoa separation using Percoll density gradients. DESIGN: We compared the spermatozoa separation obtained after density gradients from a physiological stock Percoll solution and a hyperosmotic stock Percoll solution. SETTING: Sperm samples were obtained from the Laboratory of the Biology of Reproduction at Brest, France, a public hospital. PATIENTS, PARTICIPANTS: One hundred thirty-eight healthy donors. INTERVENTIONS: None. MAIN OUTCOME MEASURE: The resolution of the separation was assessed by the number of motile spermatozoa recovered after separation using density gradients. RESULTS: The improvement of the resolution of separation is at least twofold greater with the use of hyperosmotic gradients than with that obtained by physiological gradients. Moreover, the best resolutions of separation were obtained from pathological sperm. Finally, the influence of buoyant density spermatozoa on the resolution of separation by this technique is clearly demonstrated. CONCLUSIONS: With this modification, the technique of Percoll density gradients, used for the separation of human spermatozoa, is strongly advised especially in pathological cases.

Protective effect of medroxyprogesterone acetate plus testosterone against radiation-induced damage to the reproductive function of male rats and their offspring.

This study attempted to protect spermatogenesis and the reproductive performance of rats against the effects of acute scrotal exposure to x-rays. Daily subcutaneous injections of medroxyprogesterone acetate (8 mg/kg) plus testosterone (1 mg/kg) (MT group) were administered for 55 days (experiment A) or 15 days (experiment B). The rats were irradiated (3 grays) on the last day of MT pretreatment (MTX group). In both experiments, on days 1 and 130 posttreatment, rats from each of the four groups (control, x-irradiated, MT, and MTX groups) were killed to measure the weight of the reproductive organs and the number of epididymal spermatozoa. Breeding was started 3 days posttreatment by housing all males from the four groups each with two virgin females for six successive periods of 19 days, separated by a period of 2 days. The percentage of fertile males, the litter size, postimplantation losses, and dominant lethal mutations were calculated. In experiment A, in the last fertility trial, animals of both sexes were selected at random from the progeny of each group (F1). When they were adults, their fertility was tested in a mating trial. A fertility trial was also performed with the F2 males. Our data essentially reveal that (i) in addition to their adverse quantitative effects on spermatogenesis, x-rays also produce a significant increase in dominant lethal mutations in all germ cell classes, including stem spermatogonia; (ii) the F1 and F2 male descendants of irradiated male rats provoked abnormal rates of postimplantation losses in their female mates; (iii) the short as well as the long MT pretreatment protects testicular function of irradiated rats; and (iv) in experiment A, MT pretreatment totally prevented qualitative damage to spermatozoa and protected the descendants of the irradiated animals against altered spermatogenesis as well as against genetic damage in germ cells. In conclusion, pretreatment with MT, even for a short period of time, offers a method for potentially reducing the toxic and genotoxic effects of irradiation on the male reproductive system.

Protection by steroid contraceptives against procarbazine-induced sterility and genotoxicity in male rats.

Several recent morphological studies in various mammals have suggested that partial protection of the seminiferous epithelium against cancer therapeutic agents could be obtained by treatments using gonadotropin-releasing hormone analogues or steroids. However, considering that anticancer drugs can induce genetic lesions in germ cells that may transmit abnormalities to offspring (M. Auroux and E. Dulioust, Behav. Brain Res., 16: 25-36, 1985; M. G. Horstman et al., Cancer Res., 47: 1547-1550, 1987), we believe that the assessment of a possible protection of testicular function must necessarily include tests that would detect qualitative damage of germ cells and abnormalities of the progeny. This study in adult rats aims at: (a) obtaining objective data on testicular effects of a contraceptive regimen (medroxyprogesterone acetate plus testosterone) at daily s.c. doses of 8 and 1 mg/kg, respectively, for 55 days and of an anticancer drug (procarbazine) at an i.p. dose of 150 mg/kg on Days 40, 47, and 55 of the experiment: (b) assessing the possible paternally mediated effects of these compounds on the outcome of pregnancy; and (c) attempting to prevent the possible quantitative and qualitative effects of procarbazine on treated animals and on their offspring by combining the contraceptive preparation and the anticancer drug treatments. Starting 5 days after the last injection, nine to 12 treated rats taken from each of the experimental groups were individually placed with two mature virgin females for serial mating trials. Every 20 days, and after a resting period of 5 days, the females were changed and, following parturition, fertility parameters were determined (percentage of fertile males, litter size, pre-, post-, and total implantation losses). In addition, on Days 1, 75, and 100 posttreatment, rats from each group (six to 12/group) were killed to determine testicular histology, body and reproductive organ weights, serum follicle-stimulating hormones luteinizing hormone and testosterone, and the number of spermatozoa in the cauda epididymides. Our results provide the first evidence that: (a) procarbazine induces both quantitative (histology, sperm reserves) and qualitative (fertility, postimplantation losses) damage to germ cells and, in particular, to spermatogonia which, when this does not lead to sterility, is transmitted as impaired implantation and development abilities to the male progeny; and (b) medroxyprogesterone acetate plus testosterone can successively be used as a contraceptive regimen in the adult rat which can protect testicular function against impaired spermatogenesis as well as against genetic damage in germ cells (normal fertility parameters of the male offspring).

Assessment of testicular function after acute and chronic irradiation: further evidence for an influence of late spermatids on Sertoli cell function in the adult rat.

To study cell to cell communications within the testis of adult Sprague-Dawley rats, we used acute whole body neutron plus gamma-irradiation (0.99 Gray of neutron and 0.24 Gray of gamma-rays, 3 min; Exp A) over 7-121 days postirradiation and chronic whole body gamma-irradiation (7 cGy/day 60Co gamma-rays; Exp B) over 14-84 days of irradiation and 7-86 days postirradiation. Neither irradiation protocol had an effect on the body weight of the animals. Neutron plus gamma-rays induced dramatic damages to spermatogonia, preleptotene spermatocytes, spermatozoa, and, to a lesser extent, pachytene spermatocytes. In contrast, gamma-rays induced a selective destruction of spermatogonia. Subsequently, in both experiments a maturation-depletion process led to a marked decrease in all germ cell types. A complete or near complete recovery of the different germ cell types and spermatozoa took place during the two postirradiation periods. Under both irradiation protocols Sertoli cells number was unchanged. Androgen-binding protein and FSH levels were normal in spite of the disappearance of most germ cells from spermatogonia to early spermatids. However, the decline of androgen-binding protein as well as the rise of FSH and their subsequent recovery were highly correlated to the number of late spermatids and spermatozoa. Moreover, it appeared that spermatocytes may also interfere with the production of inhibin (Exp B). With neither irradiation was Leydig cell function altered, except in Exp B in which elevated LH levels were temporarily observed. Correlation analysis suggested a relationship between preleptotene spermatocytes and Leydig cell function. In conclusion, this study establishes that chronic gamma-irradiation is particularly useful in the study of intratesticular paracrine regulation in vivo and provides further support to the concept that late spermatids play a major role in controlling some aspects of Sertoli cell function in the adult rat.

[Cytostatic treatment of the male rat: effects on offspring and protection by initial hormonal treatment]. / Traitement cytostatique chez le rat mâle: conséquences sur la descendance et effet protecteur d'un traitement hormonal préalable.

Cytostatic drugs induce the risk of anomalies in progeny. An arrest of spermatogenesis before the onset of such treatment in the male might protect the germ cells against genotoxic effects. In this study we investigate this possibility in rats by giving a hormonal treatment (medroxyprogesterone acetate plus testosterone, MPAT) which reversibly inhibits the spermatogenic process before the cytostatic treatment (cyclophosphamide, CP). Changes in body weight and behavior were found in the progeny of males treated only with CP. These anomalies were partially corrected in the group where the progenitors had received MPAT. These results agree with the hypothesis that quiescent cells are more resistant to cytostatic drugs and justify further research in this area.

Reproductive effects of the anticancer drug cyclophosphamide in male rats at different ages.

This study was undertaken to determine the effects of the anticancer and immunosuppressant drug cyclophosphamide (CP) on several endpoints of the male rat reproductive system at different ages; 10-day-old (experiment A), 45-day-old (experiment B), and adult (experiment C) Sprague-Dawley rats were injected intraperitoneally with CP at doses of 20 mg/kg/day or/week and 100 mg/kg/week for 2 weeks (experiment A), doses of 20 mg/kg/day for 5 weeks and 100 mg/kg/day for 10 days (experiment B), and doses of 20 mg/kg/day for 5 weeks (experiment C). In all groups CP induced a significant rate of mortality. Body weight gain was moderately to severely reduced in two groups of experiment A (20 mg/kg/day and 100 mg/kg/week) and of experiment B (20 mg and 100 mg/kg/day) but normal in the others. Absolute as well as relative reproductive organ weights decreased following some of the treatments in experiments A and B. At the light microscope level, effects of CP ranged from nonapparent in immature rats (experiment A, 100 mg/kg/week for 2 weeks) and young adult animals (experiment B, 100 mg/kg/day for 10 days) to moderate in the other groups treated for 5 weeks (experiments B and C). Affected tubules exhibited atrophy, exfoliation, and a decrease in the number of spermatogonia, primary spermatocytes, and round and elongated spermatids. Sertoli cell function appeared preserved, whereas Leydig cells, present in the intratubular tissue of the rats in all the experiments, were occasionally and moderately altered in animals of experiment B, as shown by significant decreases of serum testosterone and LH levels. Leydig cell dysfunction in these rats was associated with normal in vitro basal and hCG-stimulated testosterone production. A significant decrease in epididymal sperm reserves was observed only in one group of animals (experiment B, 100 mg/kg/day for 10 days). Since in these animals the number of spermatids in the seminiferous tubules was normal, it is possible that CP at a high dose alters the epididymal function. Furthermore, fertility trials demonstrated that despite no change in the number of implantation sites, there was a dramatic fall in the number of fetuses per female in all the experimental groups. In conclusion, this study shows that in pre- and postpubertal rats treated chronically or subacutely, CP primarily and essentially induces alterations of germ cells, whereas this compound has little or no direct effect upon Leydig cell and Sertoli cell functions, respectively.

Reproductive effects of the anti-cancer drug procarbazine in male rats at different ages.

Rats aged 10 days (Exp. A), 45 days (Exp. B) and 70-90 days (Exp. C) were given procarbazine intraperitoneally at doses of 30 mg/kg/day for 5 or 9 weeks (Exps A, B, C), or by gavage at doses of 5 mg/kg/day (equivalent to the therapeutic dose in man) and 50 mg/kg/day, for 9 weeks (Exp. B). A significant mortality rate was noted in immature rats (Exp. A) and in animals receiving 50 mg/kg/day orally (Exp. B). In all groups the rate of body weight gain and the weights of the testes and epididymides were reduced. Procarbazine produced disruption of the normal spermatogenetic architecture that was very severe or total in immature rats (Exp. A) and in rats given the drug at 30 mg/kg/day for 9 weeks and the highest dose (50 mg/kg) in Exp. B. Disruption of spermatogenesis was only partial in the other experimental groups. The number of Sertoli cells was not affected by the different treatments, but a Sertoli cell dysfunction (vacuolization, decreased ABP and elevated FSH concentrations), most probably secondary to germ cell degeneration, was demonstrated in those rats presenting the most severe disruption of spermatogenesis (Exp. B: i.p. and gavage, 50 mg/kg for 9 weeks). Leydig cells, always present in the interstitium, were moderately affected (decrease in serum testosterone values) in some groups at all ages whereas epididymal sperm reserves were decreased after 9 weeks (Exp. B: 30 mg/kg, i.p.; 5 and 50 mg/kg, gavage). Moreover, there was a marked fall in the number of fetuses per female mated by males in all experimental groups. We conclude that the effects of procarbazine on male reproductive function were independent of the route of administration, greater before puberty and proportional to the dose administered as well as to the duration of the treatment.

Influence of germ cells upon Sertoli cells during continuous low-dose rate gamma-irradiation of adult rats.

The effects of continuous gamma-irradiation of adult rats at two low-dose rates (7 cGy and 12 cGy/day; up to a total dose of 9.1 Gy and 10.69 Gy 60Co gamma-ray, respectively) were investigated. Over a period of 3-131 days of irradiation, groups of experimental and control animals were killed. Body weight, testis, epididymis, prostate and seminal vesicle weights, the number of germ cells and Sertoli cells, tubular ultrastructure, epididymal and testicular levels of biologically active androgen-binding protein (ABP), and the plasma concentrations of follicle-stimulating hormone (FSH), luteinizing hormone (LH) and testosterone were monitored. Irradiation had no effect on body weight, whereas testicular and epididymal weight began to decrease following 35 and 50 days of irradiation at 7 and 12 cGy, respectively. At 7 cGy the target cells of the gamma-rays were essentially A spermatogonia, whereas at 12 cGy A spermatogonia and preleptotene spermatocytes were primarily affected. This resulted in a progressive and sequential dose-related reduction in the number of pachytene spermatocytes, round spermatids and late spermatids (LS). Under both irradiation procedures the Sertoli cell number remained unchanged whereas partial (7 cGy) or no change (12 cGy) was seen at the Leydig cell level. Whatever the irradiation protocol, from the time LS numbers decreased, vacuolisation of the Sertoli cell cytoplasm progressively occurred, followed by thickening and folding of the peritubular tissue. Moreover, in parallel to the drop in the number of these germ cell types, ABP production fell whereas FSH levels rose. A highly significant positive correlation was found between LS numbers and these Sertoli cell parameters. This study supports our previous concept of a control of certain important aspects of Sertoli cell function by late spermatids in the adult rat.