Baking of methionine-choline deficient diet aggravates testis injury in mice.

Dietary pattern and cooking methods are important factors to determine the nutrients supplementation for male reproduction. Methionine and choline are two methyl donors in daily diet, which could mediate the lipid metabolism, but their effects on the sperms are not clear. In this study, we fed the mice with methionine-choline deficient (MCD) diet or the baked MCD diet for 6 weeks to evaluate this dietary pattern and the appended high temperature cooking on the spermatogenesis. The results have shown that MCD diet induced testis degradation and the damage of spermatocytes, reduced sperm vitality, motility, but elevated sperm deformity. Additionally, baking of MCD diet aggravated the testis injury, further reduced sperm density, sperm motility, and decreased normal sperm morphology dramatically. These changes were not related to the blood-testis barrier nor the Leydig cells dysfunction, but related to spermatocytes lost and apoptosis. The spermatocyte apoptosis was mediated by reticulum stress, including GRP78, XBP-1 and CHOP gene expression. Our study has shown the importance of methionine and choline in diet, and emphasized the crucial role of cooking condition, which are dietary factors to influence the quality of sperms.

[Histological study of annual cycle of gonad and germ cell development of Whitmania pigra].

The reproductive system and gonad development and germ cell occurrence of Whitmania pigra have been studied by using tissue section electron microscope techniques. W. pigra has completely independent male and female reproduction system, which lasts 11 months. The development of spermary started before the development of ovary. When egg cell is only a primordial germ cell, sperm has an initially complete form. Meanwhile, sperm cells and egg cells orderly development and synchronously mature. According to the development of sperm cells and egg cells, the development of cycle of the spermary could be divided into 6 stages: proliferating stage (1-3 months of age), growing stage (4-5 months of age), resting stage (6-8 months of age), maturing stage (9 months of age), spawning stage (10 months of age) and degradation stage (11 months of age). The development of cycle of the ovary could be divided into 6 stages: forming stage (1-2 months of age), proliferating stage (3-4 months of age), growing stage (5-8 months of age), maturing stage (9 months of age), spawning stage (10 months of age) and resting stage (11 months of age). W. pigra is a synchronous hermaphrodite animal, the development of cycle of the spermary and ovary each has six stages, sperm cells and egg cells orderly development and synchronously mature.

Toxicological assessment of multi-walled carbon nanotubes in vitro: potential mitochondria effects on male reproductive cells.

Multi-walled carbon nanotubes (MWCNTs) have been widely used in many fields and were reported to cause reversible testis damage in mice at high-dose. However the reproductive effects of low dose MWCNTs remained elusive. Herein, we used the mice spermatocyte cell line (GC-2spd) to assess the reproductive effects of MWCNTs. Size distribution, zeta potential, and intensity of MWCNTs were characterized. A maximal concentration of 0.5 µg/mL MWCNTs was found to be nonlethal to GC-2spd. At this dose, cell cycles and the ROS levels were in normal status. We also found MWCNTs accumulated in mitochondria, which caused potential mitochondrial DNA damage in spermatocyte. Furthermore, the expression level of mitochondria-related genes, the oxygen consumption rate, and cellular ATP content were declined compared to controls, even at the nonlethal dose. Our results suggested for the first time that, in germ cells, mitochondrion was a cellular organelle that accumulated MWCNTs.

In Vitro Spermatogenesis in Explanted Adult Mouse Testis Tissues.

Research on in vitro spermatogenesis is important for elucidating the spermatogenic mechanism. We previously developed an organ culture method which can support spermatogenesis from spermatogonial stem cells up to sperm formation using immature mouse testis tissues. In this study, we examined whether it is also applicable to mature testis tissues of adult mice. We used two lines of transgenic mice, Acrosin-GFP and Gsg2-GFP, which carry the marker GFP gene specific for meiotic and haploid cells, respectively. Testis tissue fragments of adult GFP mice, aged from 4 to 29 weeks old, which express GFP at full extension, were cultured in medium supplemented with 10% KSR or AlbuMAX. GFP expression decreased rapidly and became the lowest at 7 to 14 days of culture, but then slightly increased during the following culture period. This increase reflected de novo spermatogenesis, confirmed by BrdU labeling in spermatocytes and spermatids. We also used vitamin A-deficient mice, whose testes contain only spermatogonia. The testes of those mice at 13-21 weeks old, showing no GFP expression at explantation, gained GFP expression during culturing, and spermatogenesis was confirmed histologically. In addition, the adult testis tissues of Sl/Sld mutant mice, which lack spermatogenesis due to Kit ligand mutation, were cultured with recombinant Kit ligand to induce spermatogenesis up to haploid formation. Although the efficiency of spermatogenesis was lower than that of pup, present results showed that the organ culture method is effective for the culturing of mature adult mouse testis tissue, demonstrated by the induction of spermatogenesis from spermatogonia to haploid cells.

Effects of Piper hispidinervum on spermatogenesis and histochemistry of ovarioles of Spodoptera frugiperda.

The fall armyworm, Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), not only damages crops, but controlling its population also requires synthetic insecticides, which leads to selection of resistant populations and environmental contamination. Essential oils are an alternative for controlling this insect. There are few studies of the effects of these oils on the insect's reproductive system. We evaluated the effects of the long pepper, Piper hispidinervum, essential oil on the gonads of the armyworm and tested its possible influence on the fertility of this insect. Dosages of 30 and 50 mg/ml were tested in 3(rd) instar caterpillars using the leaf immersion method. Testes and ovarioles were collected, fixed with 10% formalin and embedded in Historesin. The sections were stained with toluidine blue and Mallory trichrome to detect connective tissue, periodic acid-Schiff to detect neutral carbohydrates, and bromophenol blue to detect proteins. We found that the long pepper essential oil affected negatively the spermatogenesis and altered the histochemistry of the ovarioles of S. frugiperda. The effects of long pepper oil suggest that it is a promising tool for controlling the armyworm pest.

Loss of YY1 impacts the heterochromatic state and meiotic double-strand breaks during mouse spermatogenesis.

The progression of spermatogenesis involves global changes in chromatin structure and conformation. However, our understanding of the regulation of chromatin changes in germ cells remains limited. Here we describe both in vivo RNA interference and genetic mouse knockout studies that identify a critical role for Yin Yang 1 (YY1) in mammalian spermatogenesis. In the YY1-deficient spermatocytes, we find a significant decrease in the global level of the heterochromatin markers (H3K9me3 and HP1-gamma) and a concomitant increase in the double-strand break (DSB) signals on chromosomes (gamma-H2AX, terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling, and Rad51) at the leptotene/zygotene stages of spermatocytes. These findings support a link between chromatin modifications and meiotic DSB formation, as has been seen in other model organisms. We propose that a depletion of YY1 may alter the structural integrity of heterochromatin, rendering it more accessible to the DSB machinery. In addition, YY1-deficient spermatocytes show univalent formation, increased aneuploidy, and pachytene cell death, which are likely due to defects in DNA repair. Taken together, this study identifies an important role for YY1 in mouse meiosis and provides new insight into mechanisms that regulate mammalian spermatogenesis.

Inhibition of mitomycin C-induced chromosomal aberrations by micrometer powder of selenium-enriched green tea in mice spermatocytes.

The anticlastogenic effect of micrometer powder of selenium-enriched green tea (MSTP) was evaluated by using a chromosomal aberration assay in mouse testicular cells. Animals fed with a Se-deficient diet were treated with MSTP, micrometer powder of regular green tea (MRTP), selenite, and MRTP + selenite for 30 days by an intragastric route, followed by treatment of mitomycin C (MMC) on day 19 through intraperitoneal injection (ip). Selenium status and antioxidant enzymes were measured. Results indicated that MSTP showed a significant capability to reduce the incidence of MMC-induced chromosomal aberrations in spermatocytes from 22.7% to 6.7%. This inhibitory was highest, for MSTP, at 73.1%, while it was only 38.4% for MRTP. After 30 days of a Se-deficient diet, mice, either with or without the MMC treatment, showed a lower selenium concentration in blood and liver as well as lower enzyme activity of the antioxidants, GPx and SOD. Supplementation with MSTP, selenite, or selenite + MRTP enhanced the activities of these antioxidant enzymes. This enhancement was accompanied with a concomitant elevation of selenium levels, which favored the synthesis of the seleno-enzyme GPx and protected the cells from the MMC-induced oxidative stress. Our results indicate that MSTP is both able to prevent the chromosomal aberrations induced by MMC in mouse spermatocytes and to enhance GPx and SOD activity in blood serum and liver.

[Experimental study on the effects of jujingwan on oligospermia].

OBJECTIVE: To investigate the effects of Jujingwan on the spermatozoal ultrastructure and apoptosis of germ cells in oligospermia patients. METHODS: We treated 50 oligospermia patients with Jujingwan and observed the spermatozoal ultrastructure, the apoptosis of germ cells and the changes in the DNA ploidy proportion of spermatogenic cells by electron microscopy and FCM before the treatment and 3, 6, 9 and 12 months after it. RESULTS: Jujingwan increased sperm acrosome base density 6 months after the treatment and remarkably improved the integrity of acrosome membrane 12 months after it, with no obvious pathological changes in the nuclei and tails. Three months after the treatment, cell debris and apoptotic cells decreased significantly as compared with pre-treatment (P < 0. 05) , and very significantly 12 months after the treatment (P <0. 01). The proportion of haploid spermatozoa increased very significantly (P <0.01) , and the lost primary spermatocytes decreased significantly (P <0. 05) compared with pre-treatment. CONCLUSION: Jujingwan can increase the density of sperm acrosome base and improve the pathological changes of acrosome membrane in oligospermia patients; it can improve the activity of acrosome enzyme and the integrity of acrosome membrane, decrease the apoptosis rate of germ cells and sperm and increase the percentage of haploid spermatozoa; it can also reduce the percentage of apoptotic bodies and diploid sperm cells. It is indicated that Jujingwan can inhibit the apoptosis of germ cells and sperm and improve spermatogenesis in oligospermia patients.

Annual testicular cycles and correlatory histochemical changes exhibited by the nucleus lateralis tuberis (NLT) in the Indian catfish, Clarias batrachus (linn.).

The seasonal changes observed in the neurons of the nucleus lateralis tuberis (NLT) of Clarias batrachus have been studied with particular reference to the testicular cycle throughout the year at 15 days interval. The neurons of the pars medialis (pm) and pars ventrocaudalis (pvc) subgroups of the four NLT components exhibited steady enlargements and degranulation, consistent with the spermatocyte enlargement. During spermiation phase (August), when the fishes spermiated, the neurons of pm and pvc attained their maximum size. Thus, a possible link existing between the hypothalamic nucleus (pm and pvc) and the testicular activity has been established.