Lycopene protects against cyclosporine A-induced testicular toxicity in rats

Cyclosporine A (CsA)-induced direct failures in hypothalamic-pituitary-gonadal axis and Sertoli cell phagocytic function have been considered for testicular toxicity so far. It has clearly been reported that oxidative stress leads to damage in sperm functions and structure of the testis. Therefore, this study was conducted to demonstrate whether CsA causes testicular and spermatozoal toxicity associated with the oxidative stress, and to investigate the possible protective effect of lycopene against CsA-induced damages in all reproductive organs and sperm characteristics in male rats. While the daily administration of CsA at the dose 15 mg/kg for 21 days significantly decreased the seminal vesicles weight, epididymal sperm concentration, motility, testicular tissue glutathione (GSH), glutathione peroxidase (GSH-Px) and catalase (CAT), diameter of seminiferous tubules and germinal cell thickness, it increased malondialdehyde (MDA) level and abnormal sperm rates along with degeneration, necrosis, desquamative germ cells in testicular tissue. However, the CsA along with simultaneous administration of lycopene at the dose of 10mg/kg markedly ameliorated the CsA-induced all the negative changes observed in the testicular tissue, sperm parameters and oxidant/antioxidant balance. In conclusion, CsA-induced oxidative stress leads to the structural and functional damages in the testicular tissue and sperm quality of rats and, lycopene has a potential protective effect on these damages.     

Testicular creatine and urinary creatine-creatinine profiles in mice after the administration of the reproductive toxicant methoxyacetic acid

It was previously observed that the acute or subchronic administration of some testicular toxicants, caused a significant raise in urinary creatine in rats. The aim of this study was to verify whether creatinuria could be detected in mice (a species with a different excretion profile of creatine) and whether it could be correlated to the levels of creatine in testis and to other parameters of testicular toxicity. The well known testicular toxicant methoxyacetic acid (MAA) was orally administered as a single dose (400 or 600 mg kg^-) to male adult mice B6C3F1. Twenty-four hours after dosing, urinary creatine and creatinine showed a significant reduction with respect to the pre-treatment values. At the following times post-dosing (48 and 72 h) the creatine exceeded the control and pre-treatment values, while creatinine had not yet recovered. The ratio creatine/creatinine was significantly higher than control and pre-treatment values, at 24 and 48 h after the treatments. In testis a significant, dose-dependent, decrease of creatine was observed 24 h after dosing, with a pattern related to the histopathologic alterations observed at different times after the treatments. Creatine determination was the earlier quantitative parameter of testicular toxicity, since at this time testis weights, sperm head number and enzyme activities (LDH-C4, SDH) were less affected, their maximum decrease being reached at 14 days after the treatments. These data suggest that in mice, 2-MAA could interfere with the metabolism of creatine, both in testis and other biosynthetically active tissues.     

Effect of tamoxifen treatment on motility related proteins in rat spermatozoa.

The study was undertaken to identify the effect of tamoxifen on the expression and phosphorylation of motility related proteins in the adult male rats. For this purpose, tamoxifen, at a dose of 0.4 mg/kg/day, was administered per os to the male rats for a period of 60 days. Cauda sperms, epididymal fluid and tissue proteins were extracted and analyzed by electrophoresis. Testicular tissues fixed in paraffin wax were analyzed for changes in the immunoexpression of interstitial tissue estrogen receptor alpha. Phosphorylation pattern of sperm proteins was studied in vitro after incubating with 32P-ATP. The expression of dynein and tubulin in sperms, and estrogen receptors in epididymis were analyzed by immunoblotting. Tamoxifen treatment did not alter the protein profile in the cauda sperms, epididymal fluid and tissues. Endogenous phosphorylation pattern of sperm proteins in vitro was also not affected, though it is possible that 32P incorporation observed in the 66 kDa protein could be estrogen receptor. Expression of sperm dynein, tubulin and epididymal estrogen receptors was unchanged as was the expression of testicular estrogen receptors. It was concluded that tamoxifen administration alters forward motility pattern characteristic of cauda sperm without any demonstrable change in the expression or activation of motility related proteins and the phosphorylation of the sperm estrogen receptors may be involved in the regulation of sperm motility.     

Protective action of vitamins on the spermatogenesis in lead-treated Swiss mice

The protective action of vitamins C and E against lead acetate-induced reduced sperm count and sperm abnormalities in Swiss mice has been studied. Intraperitoneal injection of lead acetate (10mg/kg body weight) in the present study stimulates lipid peroxidation in the testicular tissue, indicated by a significant increase in malondialdehyde content in the experimental mice group. This is associated with an increased generation of noxious reactive oxygen species (ROS). Significantly reduced sperm count associated with increased sperm abnormality percentage in the lead-injected mice group compared to controls substantially proves the ongoing damaging effects of lead-induced ROS on developing germ cells. However, intraperitoneal administration of vitamin C (Vit C) at a concentration equivalent to the human therapeutic dose (10 mg/kg body weight) was able to minimize significantly the testicular malondialdehyde content with a concomitant increase in sperm count and significant decrease in the percentage of abnormal sperm population. Vitamin E (Vit E) (100 mg/kg body weight) treatment of a batch of lead-injected mice had a similar effect as Vit C but with a comparatively lower efficacy. On the other hand, coadministration of both vitamins (Vit C + Vit E) at the above mentioned doses to lead-treated mice led to the most significant decline in malondialdehyde content along with elevated sperm count and reduction in the percentage of abnormal sperm population. The protective action and the synergistic action of both vitamins (C and E) against lead-induced genotoxicity are discussed.     

An assessment of the potential testicular toxicity of 10 pesticides using the mouse-sperm morphology assay

Dinitrobutylphenol, chlorbenzilate, atrazine, Ordram, Telone (dichloropropene), pentachlorophenol (technical and reagent grades), Benomyl, DBCP (dibromochloropropane), and carbaryl were tested over a range of 7 doses in the mouse to assess their testicular toxicity. Measures of potential toxicity were sperm morphology, sperm counts and testicular weights. Each pesticide was injected intra-peritoneally in a single dose on each of 5 days. Testicular toxicity was assessed at 35 days. None of the pesticides tested, including the known human male testicular toxin, DBCP, produced statistically significant differences in the parameters from vehicle-injected controls.     

Dimethyl methyl phosphonate induction of dominant lethal mutations in male mice

The reproductive toxicity of dimethyl methyl phosphonate (DMMP) was studied in the male B6C3F1 mouse. Male mice were treated with 0, 250, 500, 1000, and 2000 mg/kg DMMP by gavage 5 days per week for 13 weeks. After 4, 8 and 12 weeks of treatment the male mice were mated to untreated CD-1 female mice. At the two highest doses (1000 and 2000 mg/kg) the chemical caused a dominant lethal effect (early resorptions). Groups of male mice (at 1000 and 2000 mg/kg), mated after a 15-week recovery period without chemical dosing, had a resorption rate comparable to the control group. After 13 weeks of dosing, the male mice showed no histopathologic changes of the reproductive organs, no abnormalities in sperm concentration or sperm morphology, no evidence for hormone imbalance, no signs of general toxicity, and no effects on the fertilization rate. The male B6C3F1 mouse was less responsive than the male Fischer 344/N rat to the reproductive toxic effects of DMMP.     

Involvement of testicular DAAM1 expression in zinc protection against cadmium‐induced male rat reproductive toxicity

In order to verify the effects of exposure to Cd and Zn on testicular DAAM1 gene and protein expression and also to ascertain their involvement in the protective role of Zn in prevent the testicular toxicity Cd‐induced in male offspring rats at adult age after gestational and lactational exposure, male offspring rats, from mothers receiving either tap water, Cd, Zn, or Cd + Zn during gestation and lactation periods, were scarified on postnatal days (PND) 70. The reproductive organ (testis, epididymis, and vesicle seminal) were collected, weighed, and analyzed. The results showed that exposure to Cd in utero and through lactation decreased the relative reproductive organ weight, altered the testicular histology at the interstitial and tubular levels, and causing a significant reduction in the daily sperm production (DSP) per testis and per gram of testis, and other then altering the epididymal sperm quality. Furthermore, both mRNA and protein expression of rat testicular DAAM1 were also inhibited in Cd‐treated group. Zn supply has completely corrected the most of these toxic effects. Our results imply that Zn could prevent Cd‐induced testicular toxicity and sperm quality alteration in adult male rat after gestational and lactational exposure, probably via the restoration of the testicular DAAM1 expression inhibited by Cd.     

Morin mitigates cadmium-induced testicular impairment by stimulating testosterone secretion and germ cell proliferation in mice

Cadmium (Cd) is one of the heavy metal pollutants present in the environment due to human intervention. It is well known that Cd causes toxicological effects on various organs, including the testes. Morin hydrate is a plant-derived bioflavonoid with antioxidant, anti-inflammatory, and anti-stress properties. Thus, the question can be raised as to whether Morin has an effect on Cd-intoxication-induced testicular impairment. Therefore, the aim of this study was to investigate the role of Morin on Cd-mediated disruption of testicular activity. Mice were divided into three groups: group 1 served as the control group, group 2 was given Cd (10 mg/kg) orally for 35 days, and group 3 was given Cd and Morin hydrate (100 mg/kg) for 35 days. To validate the in vivo findings, an in vitro study on testicular explants was also performed. The results of the in vivo study showed that Cd-intoxicated mice had testicular disorganization, reduced circulating testosterone levels, decreased sperm density, and elevated oxidative stress and sperm abnormality. The expression of the germ cell proliferation marker, germ cell nuclear acidic protein (GCNA), and adipocytokine visfatin were also downregulated. It was observed that Morin hydrate upregulated testicular visfatin and GCNA expression in Cd-intoxicated mice, along with improvement in circulating testosterone, testicular histology, and sperm parameters. Furthermore, the in vitro study showed that Cd-mediated downregulation of testicular visfatin and GCNA expression, along with the suppressed secretion of testosterone from testicular explants, was normalized by Morin treatment, whereas visfatin expression was not. Overall, these data indicate that environmental cadmium exposure impairs testicular activity through downregulation of visfatin and GCNA expression, and Morin might play a protective role against Cd-induced testicular toxicity.     

Antifertility investigations on the crude chloroform extract of Carica papaya Linn. seeds in male albino rats.

Crude chloroform extract of C. papaya seeds (5 mg/animal/day, po, for 20, 40 and 60 days) was investigated for contraceptive efficacy and related side effects in male albino rats. The crude extract reduced fertility to zero per cent by 40 to 60 days of treatment. Suppression of cauda epididymal sperm motility was the most pronounced effect of the drug administration. Scanning electron microscopic observations revealed treatment induced abnormalities in sperms. Cauda epididymal and testicular sperm counts decreased following treatment. Clinical parameters did not show any alterations. Results suggest that the contraceptive effects of chloroform extract of papaya seeds are mainly post-testicular in nature without influencing toxicological profile and libido of the animals.     

Caffeine concentrations in mice plasma and testicular tissue and the effect of caffeine on the dominant lethal test.

Large groups of male Swiss mice received per os on average 100 mg caffeine per kg body weight per day for 1 or 8 weeks. The dominant lethal test was designed to achieve maximum sensitivity in order to detect any possible mutagenic effect. No mutagenic induction of dominant lethals, pre-implantation egg loss or depression of the fertility of females, caused by caffeine at the dose levels administered were observed. The half life of caffeine, which was between 2.5 and 3 h, was similar in plasma and testicular tissue. It was concluded that caffeine did not accumulate in the testicular tissue of mice. The maximum concentration of caffeine found was below 10 microgram/g testicular tissue, which is about a 100 times lower than concentrations that cause chromosome aberrations in cultured mammalian cells.     

小鼠睾丸注射不同转染试剂和注射方法对外源基因表达的影响

为探讨不同转染试剂(LipofectamineTM LTXPLUSTM、Lipofectamine2000和纳米化聚酰胺-胺型树枝状聚合物(PAMAM-D))和睾丸注射方法 (睾丸网注射、曲精细管注射和间质注射)对转基因小鼠生产效率的影响,将pEGFP-C1质粒分别与不同转染试剂混合后,按照不同的注射方法注入小鼠睾丸内,30 d后检测小鼠精子密度、活力、精子阳性率以及配种后仔鼠转基因阳性率。结果 3种转染试剂对小鼠繁殖性能影响由小到大依次为LipofectamineTM LTXPLUSTM、Lipofectamine 2000和PAMAM-D。转染后LipofectamineTM LTXPLUSTM、Lipofectamine 2000和PAMAM-D组精子的GFP阳性率分别为35.65%±0.69%、12.86%±0.35%和10.04%±0.20%。配种后仔鼠的PCR阳性率分别为29.17%、13.70%和5.88%。3种不同注射方法对小鼠睾丸都造成损伤,由小到大依次为睾丸网注射、曲精细管注射和睾丸间质注射,三者的阳性精子比例分别为35.13%±1.727%、15.13%±1.457%和0%,配种后仔鼠的PCR阳性率分别为33.3%、12.5%和0%。结果表明,LipofectamineTM LTXPLUSTM和睾丸网注射对小鼠睾丸的损伤最小,并能获得较高的转染效率。     

Spermatogenesis parameters and testosterone production at puberty as predictors of testicular functional activity in mice (<Emphasis Type="Italic">Mus musculus</Emphasis>)

The aim of this study was to investigate fertility-associated parameters of spermatogenesis and androgenic status in male laboratory mice at puberty and to assess their prognostic significance in the realization of the definitive testicular function. In three inbred murine strains, BALB/cLac, CBA/Lac and PT, the serum testosterone level, its testicular concentration, epididymal sperm count (sperm reserve) and portion of sperm with abnormal head morphology were evaluated on days 45 (puberty) and 90 (adulthood) of postnatal development. CBA/Lac males were characterized by a lower epididymal sperm count vs. other strains at both ages indicative of poorer spermatogenesis. At the same time, CBA/Lac males had a lower portion of sperm with abnormal head morphology, and this could be considered as a compensatory reaction aimed at improving sperm fertility. Distinct inter-strain differences in the portion of sperm with morphologically abnormal heads were established at both ages, while the inter-strain ratio remained invariable (BALB/cLac > PT > CBA/Lac). Thus, the level of abnormal spermatogenesis in the pubertal period may have a predictive significance for the definitive testicular activity in adult mice. No inter-strain and age-dependent changes were found in serum and testicular testosterone levels except for the PT strain, in which both testosterone levels rose from puberty to adulthood, suggesting a shift of the pubertal testosterone peak towards later times. Our data show that in male laboratory mice the genetic peculiarities of the testicular function manifest themselves during puberty and persist until adulthood.     

Damaging effect of antibiotics on the structure of synaptonemal complexes of meiotic chromosome of mice

The structure of synaptonemal complexes (SCs) of chromosomes of mouse primary spermatocytes were studied using electron microscopy on days 1, 10, and 36 after the completion of per os administration of drugs belonging to three groups of antibiotics: tetracyclins, macrolides, and fluoroquinolones. The antibiotics were administered to mice during ten days. At the substages of early and middle pachytene, heteromorphic SC bivalents and fragments of chromosome-core elements were detected in spermatocytes at all times studied after the administration of the antibiotics of three groups. As cells passed through the period from early to middle pachytene, the number of cells containing heteromorphic SC bivalents and the fragments of chromosome cores gradually decreased, which could be an indication of selection of cells with chromosomal aberrations. A high level of associations between the X chromosome and autosome bivalents (including heteromorphic ones) also favors this suggestion. A gradual decrease in the number of chromosomal aberrations was detected, as time elapsed from the completion of antibiotics administration. The study of sperm obtained from epididymises of males did not reveal significant differences in both morphology and motility of sperm between males of the control and experimental groups.     

Oocytes in newborn MRL mouse testes

Although mammals produce either sperm or eggs depending on their sex, we found oocytes in the testes of newborn MRL/MpJ male mice. In the present study, we report the morphological characteristics of testicular oocytes, the postnatal change of oocyte number per testis, and the expression of a few oocyte-specific genes in the testes of MRL/MpJ mice. The testicular oocytes had a diameter of 50-70 microm and were surrounded by zonae pellucidae, which were observed between oocytes and follicular epithelial cells. Ultrastructurally, the testicular oocytes contained numerous microvilli and cortical granules, receiving cytoplasmic projections from follicular epithelial cells. The testicular oocytes appeared as early as at birth, and the largest number was found on Day 14. The testicular oocytes were detected in only MRL strains and B6MRLF1, but not in C57BL/6, C3H/He, BALB/c, DBA/2, A/J, and MRLB6F1. The expression of the oocyte-specific genes Zp1, Zp2, Zp3, and Omt2a was detected in testes from MRL/MpJ mice. These results suggest that newborn male MRL/MpJ mice with XY chromosomes can produce oocytes in their testes and that one of the genes causing this exists on the Y chromosome.     

酒精对丙酸睾酮诱导的小鼠前列腺增生的作用

目的：探讨酒精对丙酸睾酮引起的小鼠前列腺增生（BPH）的作用及其生殖毒性。方法：成年雄性昆明系小鼠70只随机分为空白对照组（Control）、阴性对照组（Negative control,sc大豆油25 mg/（kg·d）,ig蒸馏水7.5 ml/（kg·d）,连续处理7 d、21 d）、酒精7 d和21 d组（AL7和AL21,ig 50°白酒7.5 ml/（kg·d）,连续处理7 d、21 d）,丙酸睾酮7 d和21 d组（TP7和TP21,sc丙酸睾酮注射液25 mg/（kg·d）,连续处理7 d、21 d）,丙酸睾酮+酒精7 d组（TP+AL7,sc丙酸睾酮注射液25 mg/（kg·d）,ig50°白酒7.5 ml/（kg·d）,连续处理7 d）,每组10只。末次处理24 h后处死小鼠,计算小鼠前列腺和睾丸系数,检测精子参数,测定睾丸和前列腺组织中自由基水平、抗氧化能力,观察前列腺组织病理学变化。结果：与对照组、TP7 d组、AL7和AL21 d组相比,TP+AL7 d组的前列腺系数显著提高、精子数量和质量显著降低、前列腺和睾丸MDA含量显著升高、SOD和GPx酶活力显著下降（P均< 0.05）;与TP21 d组相比,TP+AL7 d组的前列腺系数无显著差别（P>0.05））。结论：丙酸睾酮和酒精共同处理7 d就可以达到典型的前列腺增生（BPH）状态,并引起睾丸及精子的损伤,导致生殖系统的氧化应激反应增强,说明酒精对丙酸睾酮引起的小鼠前列腺增生有明显的促进作用。     

Decomposition of N-nitrosamines,and concomitant release of nitric oxide by Fenton reagent under physiological conditions

Our previous work has shown that prooxidant treatment has the propensity to induce male-mediated dominant lethal (DL) type mutations in mice. The present investigation is aimed to understand the effect of oxidative stress (OS) on DNA damage in testis, epididymal sperms and its propensity to induce sperm head abnormalities as well as its implications on male fertility in mice. Initially, employing two organic hydroperoxides, (t-butyl hydroperoxide, t-bHP and cumene hydroperoxide, cHP) as model prooxidants, induction of oxidative stress was ascertained following single/multiple sublethal doses. Further, the multiple exposure model was utilized to characterize effects on testicular weights, histoarchitecture, caudal sperm counts, lipid peroxidation, DNA damage and frequency of abnormal sperms. Single sublethal doses (1/20, 1/10 and 1/5 LD(50)) of t-bHP and cHP administered (i.p.) to adult mice resulted in only a marginal increase (20% at the highest dosage) in testicular MDA levels. However, multiple doses (1/10 and 1/5 LD(50) per day for 5 days) induced marked OS in testis and epididymal sperms as evidenced by a marked increase in lipid peroxidation at 24h after the last dose. This was associated with significant increase in the DNA damage (FADU assay) in the testicular tissue. While caudal sperm counts determined at all sampling weeks showed no treatment related alterations, analysis for head abnormalities revealed nearly 2-3-fold increase in the percent abnormal sperms among the hydroperoxide treated mice during the first 3 weeks. Furthermore, mating of prooxidant treated males sequentially for a period of 5 weeks with untreated females resulted in a significant reduction in average pup number per litter during the first 3 weeks. These results suggest that oxidative stress in testicular milieu is associated with DNA damage and produces higher frequency of abnormal sperms with significant effect on male fertility.     

Evaluation of Sclerotinia sclerotiorum as a potential mycotoxin producer on soybeans

Solvent extracts of Sclerotinia sclerotiorum sclerotia were nontoxic to mice and chicken embryos; psoralens were not detected. Solvent extracts of soybeans inoculated with 10 strains of S. sclerotiorum were toxic on injection but nontoxic on per os administration to mice. The presence of chlorinated hydrocarbons in the soybeans may partially help explain toxicity by intraperitineal injection.     

Male reproductive effect of nickel sulphate in mice

Nickel sulphate was administered orally to adult male mice at dose level of 5 and 10 mg/kg body weight (5 days per week) for 35 days. There was no change in body weight. However a significant decrease in absolute and organ-to-body weight ratios of testes, epididymides, seminal vesicles and prostate gland was observed. The sperm abnormality, associated with decrease in sperm motility and sperm count was also observed. Significant alterations in the activities of marker testicular enzymes, viz. sorbitol dehydrogenase (decreases), lactate dehydrogenase (increases) and -glutamyl transpeptidase (increases) associated with histopathological changes in testes, epididymides and seminal vesicles, were also observed. Accumulation of nickel in testes, epididymides and seminal vesicles was also observed. The study reveals that the oral exposure to nickel may affect the histology of testes, epididymides, seminal vesicles and sperms morphology. These testicular and spermatotoxic changes may be responsible for observed male mediated developmental toxic effects.     

Evaluation of Sclerotinia sclerotiorum as a potential mycotoxin producer on soybeans.

Solvent extracts of Sclerotinia sclerotiorum sclerotia were nontoxic to mice and chicken embryos; psoralens were not detected. Solvent extracts of soybeans inoculated with 10 strains of S. sclerotiorum were toxic on injection but nontoxic on per os administration to mice. The presence of chlorinated hydrocarbons in the soybeans may partially help explain toxicity by intraperitineal injection.     

Genetic variation in testicular development in mice of the C57BL/10ScSn, C57BL/6By and BALB/cBy strains and the CXB recombinant-inbred lines

When compared with C57BL/6By mice, BALB/cBy mice had testes that were 41% heavier at 60 days of age and seminiferous tubules that were 41% greater in cross-sectional area at 120 days. Absolute testicular weight did not increase between 60 and 120 days of age in either C57BL/6By or C57BL/10ScSn mice but did in BALB mice, paralleling changes in the size of the seminiferous tubules. Significant testicular growth took place over this age period in mice of all seven of the CXB recombinant-inbred (RI) strains of mice derived from a cross of the BALB/cBy and C57BL/6By strains. The wide range of phenotypes shown by adult recombinant mice, which ranged from those with significantly heavier testes than BALB to those with testes the same size (at 60 days) as those of C57BL/10ScSn mice, implied the existence of several separable factors affecting testicular size in adults. At 30 days of age the RI lines fell into two groups; one with small testes like C57BL/6By and the other with larger testes like BALB/cBy mice. The segregation pattern for prepubertal testicular weight was identical to that for the H-2 histocompatibility locus.