BackgroundHumans are ubiquitously exposed to multiple environmental contaminants. Consequences of combined action on the reproductive system remain unknown. This study aimed to assess single and joint effects of cadmium and diazinon exposure on sperm quality parameters.MethodsMale adult Wistar rats were randomized into 4 groups of ten animals each. Group A was used as a control, animals from group B were exposed to cadmium (30 mg/L), rats from group C were administered with diazinon (40 mg/L), and rats from group D were exposed simultaneously to cadmium (30 mg/L) and diazinon (40 mg/L) via drinking water for 90 days. Sperm morphology and motility were evaluated using a bright field microscope and a computer-assisted semen analysis.ResultsThe percentage of motile spermatozoa and morphologically normal sperm was markedly reduced in rats from the group B. Rats from the C group showed an increase in velocity parameters, amplitude of lateral head displacement, decrease in beat-cross frequency, and an increase in abnormal sperm morphology. Simultaneous coexposure to cadmium and diazinon increased distance and velocity parameters, and amplitude of lateral head displacement. Reductions were observed in straightness, linearity, wobble, and beat-cross frequency. The decreased normal sperm morphology rates were related to defects of the sperm tail.ConclusionsExposure to cadmium and diazinon at relatively low doses impairs sperm quality and can reduce male fertility. Cadmium and diazinon caused significant changes on sperm morphology with varying effects on motility patterns. These parameters were significantly higher in the group D as compared to the group C. The findings have important implications for reproductive risk assessment of combined exposures to multiple chemicals.

The present study aimed to elucidate the structural changes in testis and epididymis of adult rats following subchronic peroral administration of cadmium at 30 mg/L, diazinon at 40 mg/L, cadmium at 30 mg/L, and diazinon at 40 mg/L, respectively. At the end of 90-day experiment, the samples of the testes and epididymis were assayed by qualitative and quantitative histological methods. The testis and epididymis weights increased following exposure to cadmium and simultaneous exposure to cadmium and diazinon. Testicular damage following cadmium and diazinon coexposure was significantly less expressive than in groups with individual administration of these compounds. Cadmium caused a significant thickening of seminiferous epithelium, cellular degeneration, and necrosis. Desquamation of immature germ cells resulted in a significant increase of intraepithelial spaces and reduced tubule volume in all experimental groups. Vascular dilation and congestion were detected in the interstitial tissue. The changes in epididymal histology in the group exposed to cadmium and group exposed simultaneously included a reduction of epithelium, necrotic epithelial cells, vasoconstriction, and interstitial edema together with mononuclear cell infiltration. Results did not indicate a synergistic or any additional effect from the simultaneous administration of both toxicants. Further research is needed to determine the significance and the mechanism of the adverse effects.

BackgroundThe study investigated the associations of rs9340799:A > G (XbaI) and rs2234693:T > C (PvuII) polymorphisms in the estrogen receptor 1 gene (ESR1) with femoral neck (BMD-FN) and lumbar spine bone mineral density (BMD-LS), biochemical markers of bone turnover, calcium and phosphate levels, fracture prevalence, and a response to two types of anti-osteoporotic therapy in postmenopausal women from southern Slovakia.MethodsWe analysed 343 postmenopausal Slovak women (62.40 ± 0.46 years). The influence of rs9340799 (AA vs. AG + GG) and rs2234693 (TT vs. TC + CC) genotypes on BMD and biochemical markers was evaluated by covariance analysis adjusted for age and BMI. Binary logistic regression was used to evaluate the genotype effect on fracture prevalence. Pharmacogenetic part of the study included women who received a regular therapy of HT (17ß estradiol with progesterone; 1 mg/day for both; N = 76) or SERMs/raloxifene (60 mg/day; N = 64) during 48 months. The genotype-based BMD change was assessed by variance analysis for repeated measurements.ResultsWomen with AA genotype of rs9340799 had higher BMD-FN (+ 0.12 ± 0.57 of T-score) and BMD-LS (+ 0.17 ± 0.08 of T-score) in comparison with AG + GG. The rs2234693 polymorphism did not affect any of the monitored parameters. No effect of any ESR1 polymorphisms was found on fracture prevalence. Both types of anti-osteoporotic therapy had a positive effect on BMD improvement in FN and LS sites. Considering the effect of the ESR1 gene within the HT, the subjects with rs9340799/AA genotype showed worse response than those with GG genotype (− 0.26 ± 0.10 of BMD-FN T-score; − 0.35 ± 0.10 of BMD-LS T-score) and also with AG genotype (− 0.22 ± 0.08 of BMD-LS T-score). The rs2234693/TT genotype responded poorer in BMD-LS in comparison with TC (− 0.22 ± 0.08 of T-score) and CC (− 0.35 ± 0.09 of T-score). The effect of the ESR1 gene on raloxifene therapy was reported only in BMD-LS. Subjects with rs9340799/AA genotype had a − 0.30 ± 0.11 of T-score worse response compared to AG genotype. The rs2234693/TT genotype showed − 0.39 ± 0.11 and − 0.46 ± 0.15 lower T-scores in comparison with TC and CC genotypes, respectively.ConclusionsThe rs9340799 polymorphism may contribute to decreased BMD in postmenopausal women from southern Slovakia; however, this is not related to higher fracture prevalence. Concurrently, both polymorphisms affected a response to analysed anti-osteoporotic therapies.Electronic supplementary materialThe online version of this article (10.1186/s12881-018-0684-8) contains supplementary material, which is available to authorized users.

In this study, the effects of nickel chloride (NiCl(2)) applied per os on testis histopathology and morphometry of mice were investigated. The metal was applied in pellets at a dose of 10 mg NiCl(2)/kg bw to male mice 4 weeks of age. After 3, 6, 9 and 12 weeks of nickel administration, the relative volume of whole seminiferous tubule, germinal epithelium, tubule lumen, interstitium and blood vessels as well as the diameter of seminiferous tubules were determined in the experimental and corresponding control groups. Microscopic examination of testis showed significant changes in all nickel-exposed groups. The degeneration of germinal epithelium, with released germ cells into the lumen of the tubules, and occurrence of empty spaces in the seminiferous epithelium were found in all experimental groups. The changes in the testes were time-dependent. The relative volume of empty spaces in the seminiferous epithelium significantly increased (P < 0.001) in all experimental groups when compared with the corresponding control. A significant decrease in the relative volume of seminiferous epithelium was observed after 6 and 12 weeks of Ni-exposure. The increased luminization of the tubules was found after 6 (P < 0.001), 9 (P < 0.01) and 12 (P < 0.001) weeks. Interstitial tissue significantly decreased after 6 and 9 weeks of Ni exposure and increased after 12 weeks of Ni intake. The seminiferous tubule diameter significantly (P < 0.001) decreased after 12 weeks. Results of this study report a serious, time-dependent changes in the testes, mainly in the germinal epithelium, after a peroral intake of nickel.