scholarly journals Disruption of sexual function, FSH secretion, and spermiogenesis in rabbits following developmental exposure to vinclozolin, a fungicide

Reproduction ◽  
2006 ◽  
Vol 131 (4) ◽  
pp. 805-816 ◽  
Author(s):  
D N R Veeramachaneni ◽  
J S Palmer ◽  
R P Amann ◽  
C M Kane ◽  
T T Higuchi ◽  
...  

We studied sequelae of prenatal plus infantile exposure of male rabbits to vinclozolin, because it is ingested by women and children. Female Dutch-Belted rabbits (7–10/group) were treated daily per orum from gestation day 15 through post-natal week 4 to provide 0, 7.2, or 72 mg vinclozolin/kg dam’s body weight/day. Vinclozolin had no effect on maintenance of pregnancy, growth of pups, age at testicular descent or weight of organs. Concentrations of serum LH or testosterone at 6, 12, or 24 weeks of age were unaffected. However, FSH was lower (P< 0.05) in both vinclozolin groups at all three ages. Following injection of GnRH at 12 or 24 weeks, the increase in FSH was less (P< 0.05) in both vinclozolin groups, as was testosterone at 12 weeks of age. After full sexual maturity, 2 of 7 low dose rabbits were uninterested in female or male teasers and never achieved erection or ejaculation. Overall, rates of ejaculation failure were: control 0% (0/48), low dose 29% (12/42), and high dose 5% (3/60). Daily sperm production per gram of testis and total number of sperm per ejaculate in both vinclozolin groups were similar (P> 0.1) to controls. However, semen from vinclozolin rabbits contained over two times more (P< 0.05) morphologically abnormal spermatozoa, mostly nuclear and acrosomal defects, than semen from controls. Seminiferous tubules with degenerative changes were more frequent (P< 0.05) in vinclozolin rabbits than in controls. Lesions included syncytia of spherical spermatids and desquamation of germ cells. Hence, developmental exposure to vinclozolin caused presumably permanent changes in copulatory ability, secretion of FSH, and spermiogenesis.


Author(s):  
Xin Dai ◽  
Xiao-Feng Sun ◽  
Ai-Qin Wang ◽  
Wanhong Wei ◽  
Sheng-Mei Yang

Gallic acid (GA), a phenol that is present in various plants, potentially contains antioxidant properties. This study aimed to investigate the effects of GA on the reproduction of adolescent male Brandt’s voles (Lasiopodomys brandtii (Radde, 1861)). Antioxidant levels and apoptosis in the testis, as well as reproductive physiology, were evaluated in adolescent males treated with GA. The results showed that a low dose of GA enhanced relative epididymis weight and the sperm density in the epididymis, increased the mRNA levels of steroidogenic acute regulatory protein in the testis, and reduced the percentages of abnormal and dead sperm. In addition, a low dose of GA significantly increased the levels of superoxide dismutase, catalase, and glutathione peroxidase, and decreased the level of malondialdehyde in the testis, as well as the mRNA and protein levels of the apoptosis related gene, caspase-3. However, a high dose of GA sharply reduced the average diameter of the seminiferous tubules compared to a low dose. Collectively, these findings demonstrate that GA treatment during puberty affects the reproductive responses of male Brandt’s voles in a dose-dependent manner by regulating antioxidant levels and apoptosis.



2016 ◽  
Vol 96 (1) ◽  
pp. 1-17 ◽  
Author(s):  
Michael D. Griswold

Mammalian spermatogenesis requires a stem cell pool, a period of amplification of cell numbers, the completion of reduction division to haploid cells (meiosis), and the morphological transformation of the haploid cells into spermatozoa (spermiogenesis). The net result of these processes is the production of massive numbers of spermatozoa over the reproductive lifetime of the animal. One study that utilized homogenization-resistant spermatids as the standard determined that human daily sperm production (dsp) was at 45 million per day per testis (60). For each human that means ∼1,000 sperm are produced per second. A key to this level of gamete production is the organization and architecture of the mammalian testes that results in continuous sperm production. The seemingly complex repetitious relationship of cells termed the “cycle of the seminiferous epithelium” is driven by the continuous commitment of undifferentiated spermatogonia to meiosis and the period of time required to form spermatozoa. This commitment termed the A to A1 transition requires the action of retinoic acid (RA) on the undifferentiated spermatogonia or prospermatogonia. In stages VII to IX of the cycle of the seminiferous epithelium, Sertoli cells and germ cells are influenced by pulses of RA. These pulses of RA move along the seminiferous tubules coincident with the spermatogenic wave, presumably undergoing constant synthesis and degradation. The RA pulse then serves as a trigger to commit undifferentiated progenitor cells to the rigidly timed pathway into meiosis and spermatid differentiation.



2011 ◽  
Vol 2 (1) ◽  
pp. 36-48 ◽  
Author(s):  
R. L. Ruhlen ◽  
J. A. Taylor ◽  
J. Mao ◽  
J. Kirkpatrick ◽  
W. V. Welshons ◽  
...  

Exposure of fetuses to endocrine disrupting chemicals (EDCs), such as the estrogenic drug diethylstilbestrol (DES), disrupts development of the reproductive system and affects other aspects of adult phenotype including diseases, consistent with the developmental origins of health and disease hypothesis. To determine whether diet could influence the effects of DES, we compared mice fed a commonly used combination of soy-based Purina 5008 (breeding and lactation) and 5001 (post-weaning) with mice fed soy-based Purina 5002 throughout life. We exposed fetal CD-1 mice (F1) in utero on different feeds to a 0 (controls), low (0.1 μg/kg/day) or high (50 μg/kg/day) dose of DES via feeding the dam (F0) on gestation days 11–17. Compared to 5008, 5002 feed significantly increased serum estradiol in control fetuses. On 5008 (but not 5002) feed, DES significantly increased fetal serum estradiol at a low dose and reduced it at a high dose. Diet influenced the effects of in utero DES on F1 female onset of puberty and the uterine response to estradiol (an inverted-U dose–response relationship seen for DES on uterine weight with 5008/5001 feed was not observed with 5002). Both low- and high-dose DES reduced daily sperm production (DSP) in adult F1 males on 5008/5001 feed, whereas males fed 5002 showed no DES-induced reduction in DSP. Thus, we observed a number of low-dose effects of in utero DES exposure on Purina 5008/5001 feed that were not observed using Purina 5002, a feed commonly used in industry-funded toxicological studies conducted for regulatory purposes.



1999 ◽  
Vol 18 (9) ◽  
pp. 583-589 ◽  
Author(s):  
P R Dalsenter ◽  
E Dallegrave ◽  
J Rb Mello ◽  
A Langeloh ◽  
R T Oliveira ◽  
...  

1 The reproductive effects of endosulfan on the male offspring of rats were examined. Dams were treated orally with 0, 1.5 or 3.0 mg endosulfan/kg from day 15 of pregnancy to postnatal day (PND) 21 of lactation. The male offspring rats were investigated at PND 65 or 140, corresponding to the pubertal and adulthood stage of development. 2 The dose of 3.0 mg endosulfan/kg induced a decrease in maternal body weight during pregnancy, but litter size and mean birth weight were not affected. Similarly, the age at testis descent and preputial separation was not affected on the male offspring. 3 The daily sperm production (6106) was permanently decreased in the highest dose group when investigated at puberty and at adulthood. At the lowest dose, however, the daily sperm production was significantly reduced only at puberty. 4 Histologically, the percentage of seminiferous tubules showing complete spermatogenesis was significantly decreased at puberty. This finding may explain the decrease in daily sperm production observed in the endosulfan-exposed male rats. 5 The results of this study show that low doses of endosulfan have no apparent effect on developmental landmarks or on the weight of reproductive and accessory sex organ. Daily sperm production was the most susceptible endpoint in the male offspring exposed to endosulfan during pregnancy and lactation. To further understand the reproductive effects of endosulfan on male rat offspring, additional reproductive and toxicokinetic studies should be carried out to determine the extent of endosulfan exposure in male rat offspring in utero and during lactation.



2021 ◽  
Vol 26 (1) ◽  
Author(s):  
Hizb Ullah ◽  
Faizan Ullah ◽  
Owais Rehman ◽  
Sarwat Jahan ◽  
Tayyaba Afsar ◽  
...  

Abstract Background The industrial revolution has resulted in increased synthesis and the introduction of a variety of compounds into the environment and their potentially hazardous effects have been observed in the biota. The present study was aimed to evaluate the potential endocrine-disrupting effects of chronic exposure to the low concentrations of bisphenol S (BPS) in male rats. Methods Weaning male Sprague-Dawley rats (22 days old) were either exposed to water containing 0.1% ethanol for control or different concentrations of BPS (0.5, 5, and 50 μg/L) in drinking water for 48 weeks in the chronic exposure study. After completion of the experimental period, animals were dissected and different parameters (hormone concentrations, histology of testis and epididymis, oxidative stress and level of antioxidant enzymes in the testis, daily sperm production (DSP), and sperm parameters) were determined. Results Results of the present study showed a significant alteration in the gonadosomatic index (GSI) and relative reproductive organ weights. Oxidative stress in the testis was significantly elevated while sperm motility, daily sperm production, and the number of sperm in epididymis were reduced. Plasma testosterone, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) concentrations were reduced and estradiol levels were high in the 50 μg/L-exposed group. Histological observations involved a significant reduction in the epithelial height of the testis along with disrupted spermatogenesis, an empty lumen of the seminiferous tubules, and the caput region of the epididymis. Conclusion These results suggest that exposure to 5 and 50 μg/L of BPS for the chronic duration started from an early age can induce structural changes in testicular tissue architecture and endocrine alterations in the male reproductive system which may lead to infertility in males.



Zygote ◽  
2016 ◽  
Vol 24 (5) ◽  
pp. 783-793 ◽  
Author(s):  
Nathália L.M. Lara ◽  
Ivan C. Santos ◽  
Guilherme M.J. Costa ◽  
Dirceu A. Cordeiro-Junior ◽  
Antônio C. G. Almeida ◽  
...  

SummaryThe spiny rat (Proechimys guyannensis) is a neotropical rodent that is used in biomedical research, particularly research related to chronic resistance to epilepsy and infectious diseases. To our knowledge, there are few reports concerning the reproductive biology of this species. Therefore, besides providing basic biometric and morphometric data, in the present study we investigated testis function and spermatogenesis in adult spiny rats. The mean testis weight and gonadosomatic index obtained were 1.63 ± 0.2 g and 1.15 ± 0.1% respectively. Based on the development of the acrosomic system, 12 stages of the seminiferous epithelium cycle were characterized. Stages VI and VII presented the highest frequencies (~17–19%), whilst stages II to V showed the lowest frequencies (~2–4%). The most advanced germ cell types labelled at 1 h or 20 days after BrdU injections were respectively preleptotene/leptotene spermatocytes at stage VII and elongated spermatids at stage III. The mean duration of one cycle was 7.5 ± 0.01 days and the entire spermatogenic process lasted 33.7 ± 0.06 days (~4.5 cycles). The seminiferous tubules (ST) occupied ~96 ± 1% of the testis parenchyma, whereas Leydig cells comprised only 1.5 ± 0.4%. The number of Sertoli cells (SC) per testis gram and the SC efficiency (spermatids/SC) were respectively 78 × 106 ± 11 × 106 and 7.9 ± 1. The daily sperm production per testis gram (spermatogenic efficiency; daily sperm production (DSP)/g/testis) was 78 × 106 ± 8 × 106. To our knowledge, this spermatogenic efficiency is among the highest found for mammals investigated to date and is probably related to the very short duration of spermatogenesis and the very high ST percentage and SC number obtained for this species.



PLoS ONE ◽  
2021 ◽  
Vol 16 (5) ◽  
pp. e0251256
Author(s):  
Dirceu A. Cordeiro ◽  
Guilherme M. J. Costa ◽  
Luiz R. França

Although rodents represent approximately 40% of all living mammalian species, our knowledge regarding their reproductive biology is still scarce. Due to their high vulnerability to environmental changes, wild rodents have become beneficial models for ecological studies. Thus, we aimed to comparatively investigate key functional testis parameters in four sexually mature wild rodent species (A. cursor, A. montensis, N. lasiurus, and O. nigripes). These species belong to the Cricetidae family, which is the most diverse family of rodents in South America, with a total of ~120 species in Brazil. The results found for the gonadosomatic index and the sickled sperm head shape observed strongly suggest that the species here evaluated are promiscuous, prolific, and short-lived. The duration of spermatogenesis was relatively short and varied from ~35–40 days. Both the percentage of seminiferous tubules (ST) in the testis parenchyma (~95–97%) and the number of Sertoli cells (SC) (~48–70 million) per testis gram were very high, whereas a fairly good SC efficiency (~8–13 round spermatids per SC) was observed. In comparison to other mammalian species studied, particularly the rodents of the suborder Myomorpha (i.e. hamsters, rats and mice), the rodents herein investigated exhibited very high (~62–80 million) daily sperm production per testis gram. This impressive spermatogenic efficiency resulted mainly from the short duration of spermatogenesis and quite high values found for the ST percentage in the testis and the SC number per testis gram. We expect that the knowledge here obtained will help conservation programs and the proper management of wildlife.



1987 ◽  
Vol 36 (2) ◽  
pp. 301-308 ◽  
Author(s):  
William B. Neaves ◽  
Larry Ohnson ◽  
Charles S. Petty


2002 ◽  
Vol 29 (2) ◽  
pp. 165 ◽  
Author(s):  
H. Gonçalves ◽  
P. C. Alves ◽  
A. Rocha

To establish a successful strategy for managing wild rabbit (Oryctolagus cuniculus algirus) populations it is essential to have a clear understanding of reproductive biology. In Portugal, previous work suggested a seasonal pattern of reproductive activity for this species. In this study we present additional information on the seasonal reproductive activity of the wild rabbit as well as data on the influence that environmental factors have on the onset and length of the breeding season. The study was carried out in Pancas, southern Portugal, from October 1997 to September 1998. Rabbits were collected every two months and post mortem analyses were performed. In the males, circulating concentration of testosterone, gonadal weight, daily sperm production, diameter of the seminiferous tubules and the thickness of epithelial cells were measured. The numbers of corpora lutea, embryos and placental scars were recorded in the females. To assess abundance and quality of food, samples of herbaceous vegetation were collected and analysed for water, fibre and crude protein content. The reproductive season extended from November to June with a peak in March/April, with both sexes showing an annual cycle of gonadal development and subsequent regression. All analysed females were pregnant and/or lactating between March and June. The mean litter size estimated by counting the embryos in the uteri was 3.90 ± 0.50. Daily sperm production was highest between November and April. Testicular function was strongly correlated with environmental temperature and the water content of the vegetation, and both testicular and ovarian development were correlated with vegetation biomass.



Author(s):  
F. C. Anacletus ◽  
B. Nwakaku ◽  
K. T. Nwauche

The antioxidant protective effects of fruit juice of cucumber and watermelon on lipid profile of cadmium induced toxicity on male albino rats was investigated. Forty male rats were divided into eight groups. Group NC served as normal control group while group PC was positive control that was not treated but induced with cadmium. Groups I to VI received high dose and low dose of juice of Cucumber and Watermelon respectively. Excluding the normal control group, other groups were fed with lard 14 days before treatment commenced.  Doses of 0.8 mg/kg-high dose and 0.4 mg/kg-low dose for cucumber and watermelon respectively. At the 4th and 6th week, biochemical parameters were assayed. Results revealed that the levels of total cholesterol, LDL, VLDL and triglyceride significantly (P˂0.05) were decreased compared to positive control but HDL was increased in treatment groups compared to positive control. Pretreatment with cucumber and watermelon juice indicated that total cholesterol, LDL, VLDL and triglyceride significantly (P˂0.05) were decreased compared to positive control but HDL was increased in treatment groups compared to positive control. The result also revealed an increase in testosterone levels in treated groups after 4 weeks of administration of whole extract of cucumber and watermelon when compared to their week 2 values. Testosterone level in positive control was also reduced significantly from 1.5±0.14 ng/ml to 0.46±0.31 ng/ml. Histological evaluation of the testes of normal control group revealed that the interstitium was intact with leydig cells present and maturing germ cells embedded in normal seminiferous tubules while the other groups that were induced with cadmium only showed morphology of testes with empty seminiferous tubules and consolidated interstitial spaces.



Sign in / Sign up

Export Citation Format

Share Document