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Polybrominated biphenyl ether (PBDE) is a kind of brominated aromatic hydrocarbon commonly used as a flame retardant and now considered as one of the persistent organic pollutants, which generally exists in the environment and organisms. Studies have shown that PBDEs have an endocrine disrupting effect, neurotoxicity, developmental toxicity, reproductive toxicity, and the ability of inducing reproductive toxicity in men by reducing semen quality, affecting testis germ cells and interfering with reproductive hormone levels. Although PBDEs have been banned in some countries, they do exist in our environment. Therefore, more studies are needed to reveal their potential toxicity and mechanisms, so as to monitor, predict and prevent their pollution. This review focuses on the male reproductive toxicity of PBDEs.

To study the protective effects of Wuzi Yanzong recipe on testis germ cell apoptosis in natural ageing rats through endoplasmic reticulum stress (ERS), 16-month-old male SPF grade SD rats were randomly divided into three groups: ageing model group, and low and high-dose Wuzi Yanzong recipe groups (WZ, 1 and 4 g·kg⁻¹), with 10 rats in each group. In addition, 2-month-old SD male rats were used as adult control group. The ageing model group and the adult control group were fed with normal diet for 4 months. WZ groups were given the medicated feed for 4 months. After fasting for 12 hours, the rats were put to death. Then, the testes were immediately collected. The change of testicular tissue morphology was observed by HE staining. The expression levels of ER stress-related proteins GRP78, p-PERK, p-eif2 α , ATF4, p-IRE1, XBP1, ATF6 and apoptosis-related proteins CHOP, caspase12 and p-JNK in testes were detected by Western blot. Compared with the ageing model group, Wuzi Yanzong recipe alleviated the morphological changes of testicular tissue. Western blot results showed that Wuzi Yanzong recipe significantly increased the expression levels of endoplasmic reticulum stress-related proteins GRP78, p-PERK, p-eif2 α , ATF4, p-IRE1, XBP1, ATF6 and significantly decreased the expression levels of endoplasmic reticulum-induced apoptosis-related proteins CHOP, caspase 12 and p-JNK. In conclusion, Wuzi Yanzong recipe can alleviate the ageing-related apoptosis of testicular germ cells in natural ageing rats by regulating endoplasmic reticulum stress., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Chinese Pharmaceutical Association.)

Objective: To determine whether the immunopotentiator chitosan oligosaccharide(COS)can recover the reproductive functions of pathological ovarian recession mice and improvetheir immunity., Methods: Forty-three fertile female mice (at around 2 months),in addition to a normal control group ( n =8), injected intraperitoneally with busulfan and cyclophosphamide to construct premature ovarian failure mod-els. Three of them were used to test whether the infertility model was constructed successfully by HE staining. Then the models were randomly divided into four groups ( n =8) and treated with different dosages of COS by gavage, after which compared different groups' organ ratios (the weight of immune organs and ovary/body weight), ovarian follicles and peritoneal macrophages' phagocytosis as well as estragon(E 2 ) and pro-gesterone(P) levels in peripheral blood. In addition, we measured the expression dynamics of the ovarian protein reproductive cell marker mouse vasa homolog(MVH), germ stem cell marker OCT-4 in ovarian surface epithelium (OSE) and part of immune factors including tumor necrosis factor (TNF-α),interleukin-2(IL-2)as well as IL-6 to analyze the correlativity between germline stem cells marker dynamics and im-mune factors expression changes., Results: With increasing dosages of COS, organ ratios of ovaries, thymus and spleen both went up syn-chronously; The whole number of follicles and every stages of follicles are all presenting with progressive tendency; E 2 level in peripheral blood ascends, however, progesterone level declined relatively; Neutral red experiment revealed the phagocytosis ability of peritoneal macrophages became stronger with increasing dosages of COS; the results of Western blot had shown that no matter the expression level of germ stem cells marker or immune factors were all presenting increasing tendency, which means that the expression level dynamics of germ stem cell marker has a positive correlation with immune factors expression changes. The results were statistically significant., Conclusions: COS could improve the immunity of mice with pathological ovarian recession and at the same time it would promote the proliferation and differentiation of female germ line stem cells (FGSCs), and then helped saving ovarian functionsto some extent.

Objective: To investigate the effects and mechanisms of diethylhexylphthalate (DEHP) on morphology and function of progenitor Leydig cells (PLC) in rats., Methods: Twenty pregnant SD rats were randomly divided into 4 groups ( n = 5): normal control group, DEHP low dose group , middle dose group, and high dose group, which were treated from postnatal day (PND) 1 to PND 21 of the pubs with DEHP at the doses of 0, 10, 100, 750 mg/(kg · d) in 0.5 ml of corn oil by gavage respectively. At the end of the treatment, the male pups were killed and blood samples were collected for determination of serum testosterone concentration by chemiluminescence method. The body weight, testis weight and anogenital distance (AGD) were measured. The morphology of PLC was observed by light and transmission electron microscopy. The protein expression of steroidogenic acute regulatory protein(StAR) in PLC was determined by immunohistochemistry. The mRNA expression of insulin-like growth factor-I (IGF-I) in the testis was assayed by real-time PCR., Results: Compared with normal control group, the serum testosterone and AGD of male pubs from the middle and high dose groups were declined significantly (P < 0.01), the testis weight and body weight from high dose group were decreased significantly (P < 0.01), while the testis weight increased in the low dose group (P < 0.05). Under light microscope, PLC showed hyperplasia and cluster aggregation in the low dose group and focal hyperplasia in the middle and high dose group. The spermatogenic cells in seminiferous tubules showed decrease, apoptosis and unfix in the high dose group. Under transmission electron microscope, the PLC showed decreased lipid droplets, smooth endoplasmic reticulum and mitochondriae in the treated group. The mRNA expression of IGF-I increased in the low dose group, and the protein expression of StAR decreased in the middle and high dose group., Conclusion: Lactating exposure to DEHP may interfere with the synthesis of testosterone of PLC in male pubs, the decrease of StAR and the damage of PLC may be involved in it.

Objective: To investigate the effects of Zuogui pill, Yougui pill and the relative compositions on the differentiation towards germ cells of stem cells., Method: The rat drug sera for Zuogui pill, Yougui pill and the common composition of Zuogui pill and Yougui pill were prepared respectively as the experimental drugs; the mouse embryonic stem cell 1B10 (MESC-1B10) was used as the representative of stem cells; the above rat drug sera were used to intervene MESC-1B10 and the process was traced by microscopy imaging; after 72 h of the intervention, the RNAs were extracted from the different intervened MESC-1B10, cDNAs were synthesized immediately and finally the Real-time quantitative PCR (qPCR) was used to measure the expression patterns of the 10 reproductive-differentiation-related genes for each intervention., Result: The rat drug serum of Zuogui pill (ZGW-RS) significantly up-regulated Oct-4 and SCP3 and significantly down-regulated GDF-9 and Stra8; the rat drug serum of Yougui pill (ZGW-RS) significantly up-regulated Oct-4, GDF-9, Mvh and SCP3 and significantly down-regulated Stra8, Itga6 and Itgb1; the rat drug sera for the common composition of Zuogui pill and Yougui pill (ZGWYGW-RS) significantly up-regulated Oct-4, SCP3 and ZP3 and significantly down-regulated GDF-9, Stra8, Itga6 and Itgb1., Conclusion: ZGW-RS can initiate the change towards meiosis, but can not start the reproductive differentiation of MESC-1B10; YGW-RS can initiate the change towards meiosis, and can also start the reproductive differentiation of MESC-1B10 towards female germ cells; ZGWYGW-RS can initiate the change towards meiosis, and can lightly start the reproductive differentiation of MESC-1B10 towards female germ cells but the inductive effect is smaller than YGW-RS. The experimental results, on one hand, strengthen the knowledge about the influence of the relative compositions of Zuogui pill and Yougui pill on the reproductive differentiation of stem cells, on the other hand, help to explain the mechanism of the treatment of the infertility by Zuogui pill and Yougui pill.

Objective: To investigate the effect of carbon disulfide (CS(2)) on the mitochondrial respiratory chain in testicular spermatogenic cells in male rats and to explore the possible mechanism of reproductive system damage caused by CS(2) in male rats., Methods: Twenty-four male Sprague-Dawley rats (clean grade) were randomly divided into four groups: three CS(2) exposure groups (CS(2) concentrations: 50, 250, and 1250 mg/m(3)) and a control group. The rats in CS(2) exposure groups were exposed to CS(2) by static inhalation for 10 weeks (2 h/d, 5 d/w), while the rats in control group were exposed to air. Then, all rats were sacrificed by decapitation; testicular tissues were collected, and mitochondrial protein in spermatogenic cells were extracted; the levels of mitochondrial respiratory chain enzyme complex I∼V were measured by enzyme-linked immunosorbent assay., Results: Compared with the control group, all CS(2) exposure groups had significantly increased levels of mitochondrial respiratory chain enzyme complex I∼V in spermatogenic cells (P < 0.05). There were no significant differences in the levels of respiratory chain enzyme complex I∼IV between the CS(2) exposure groups (P < 0.05), but the level of respiratory chain enzyme complex V rose significantly as the concentration of CS(2) increased (P<0.05)., Conclusion: Various levels of CS(2) exposure may increase the levels of mitochondrial respiratory chain enzyme complex in testicular spermatogenic cells among male rats, thus affecting the normal oxidative phosphorylation in mitochondria.

Objective: To study the effect of hypoxia on hypothalamus-adenohypophysis-testis axis hormone levels, germ cell apoptosis and hypoxia-inducible factor-1alpha (HIF-1alpha) expression in testis of adolescent mice, and explore HIF-1alpha regulation on the reproductive function of male mice., Methods: Eighty SPF grade adolescent C57BL/6 mice were randomly divided into normoxia group, hypoxia 3, 7, 14 and 28 d groups. The level of serum testosterone (T), free testosterone (FT), follicle-stimulating hormone (FSH) and luteinizing hormone (LH) was analyzed by ELISA. Detected the sperm count, motility rate and abnormal sperm rate of epididymal sperm suspension. The apoptosis cells in testis were determined using TUNEL method. The expression of HIF-1alpha was analyzed using Western blot., Results: Compared with corresponding normoxia group, serum T, FT, FSH and LH concentrations in hypoxia 3 d group were significantly higher (P < 0.05); T and LH concentrations in hypoxia 14 d group were significantly lower (P < 0.05). Sperm count and motility rate in hypoxia 7 and 14 d groups significantly declined (P < 0.05); abnormal sperm rate in all hypoxia groups significantly increased (P < 0.05). The apoptosis index (AI) of germ cells in hypoxia 7, 14 and 28 d groups significantly increased (P < 0.05), and the levels of HIF-1alpha protein expression were significantly higher (P < 0.05)., Conclusion: HIF-1alpha protein highly expressed in mice testis could induce germ cell apoptosis increased in chronic hypoxia environment.

Objective: To investigate the protective effect of lycium barbarum polysaccharides (LBP) against heat stress-induced apoptosis of germ cells in rats and its action mechanism., Methods: Ninety male Sprague-Dawley rats were randomly divided into five groups of 18 each: control, heat stress (HS), high-dose LBP, median-dose LBP and low-dose LBP. The rats of the three LBP groups were given LBP by intragastric administration at 100 mg/(kg x d), 50 mg/(kg x d) and 10 mg/(kg x d) respectively for 14 days, and on the 15th day they, together with those of the HS group, were exposed to a heat of 43 degrees C for 30 minutes. At 24 h, 48 h and 7 d after heat stress, the animals were killed by cervical dislocation, followed by observation of the apoptotic germ cells by TUNEL, determination of the expression of Caspase-3 by immunohistochemistry and detection of cytochrome C in the cytosol by ELISA., Results: Compared with the HS group, the three LBP groups showed statistically significant decreases in the apoptosis index (P<0.05), the expression level of Caspase-3 in germ cells (P<0.05) and the concentration of cytochrome C in the cytosol (P<0.05)., Conclusion: LBP can inhibit cytochrome C release from mitochondria, decrease the expression of Caspase-3 and hence reduce the apoptosis of germ cells. It thus can be deduced that LBP can protect germ cells against apoptosis via the mitochondrial pathway.

By using rat testicular germ cells in vitro toxicity testing method based on original cells culture, the reproduction toxicity of sewage treatment plant effluent of Chemical Industrial Park along the Yangtze River was evaluated, through cells changes in morphologic, activity and viability parameters. The results showed that both of the effluents from new developed Chemical Industrial Park A and provincial Chemical Industrial Park B contain reproductive toxic substances. The toxicity of Park A has more significant undergone changes in cells activity of sertoli cells (p < 0.01), spermatogenic cells (p < 0.05) and leyding cells (p < 0.05), lactate dehydrogenase activity (p < 0.01) and testosterone secretion (p < 0.01) than that of Park B. Sepermatogenic cells are more sensitive in indicating reproduction toxicity for testicular, compared with leyding cells and sertoli cells. This study demonstrated that, as an indispensable and complementary tool for water quality assessment, rat testicular germ cells in vitro toxicity testing based on original cells culture can be used to comprehensively evaluate the reproduction toxicity of sewage treatment plant effluent, and provide prompt and useful discharge quality information.

Objective: To investigate the protective effect of pentoxifylline on spermatogenesis following testicular torsion/detorsion in rats., Methods: Healthy male Sprague-Dawley rats (n = 24) were divided into three groups randomly, each comprising 8 rats. In Group I, rats underwent a sham operation. In Group II and III, animals were submitted to unilateral 720 degrees testicular torsion, then detorsion in two hours. Infusion of isotonic saline and pentoxifylline into tail vein was initiated 15 minutes prior to relief of torsion in Group II and III respectively. Twenty four hours later, testes were examined for evidence of germ cell apoptosis by the flow cytometry and the level of total antioxidant capability (T-AOC) and malondialdehyde (MDA) by spectrophotometry., Results: Compared with that of group II, the number of apoptotic germ cell and the level of MDA decreased remarkably in Group III, but T-AOC increased significantly (P <0.01)., Conclusion: Pentoxifylline provided significant rescue of testicular function after acute experimental torsion.

Objective: To investigate the relationship between germ cells apoptosis and alterations of total antioxidant capacity (T-AOC), nitric oxide(NO) level and nitric oxide synthase (NOS) activity in the testes of rats submitted to alcohol drinking., Methods: Twenty healthy male Sprague-Dawley rats (3 months old) were randomly divided into two groups: control group and experimental group. 50% alcohol and distilled water were administered intragastrically at a dose of 10 ml/kg body weight to two groups of rats respectively. After twenty-six days, the biochemical parameters (T-AOC, NO level and NOS activity) were measured with spectrophotometric determination. The TdT-mediated dUTP-X nick end labeling (TUNEL) technique was used to detect germ cells apoptotic index (AI)., Results: Compared with the control group, AI was significantly higher (P < 0.01) in the experimental group; T-AOC level reduced obviously (P < 0.01), but NO level and NOS activity increased predominantly ( P < 0.01)., Conclusion: The excessive production of NO caused by the increasing of NOS activity and the decreasing of T-AOC may be the main causes that alcohol overtaking induces germ cells apoptosis.

Objective: In this paper, toxicity of SO2 on male reproductive system of mice was studied., Methods: 40 mice were divided to 4 groups (10/group): a group for control, the other 3 groups for SO2 inhalation (28, 56, 112mg/m3), 4h/d, 7d., Results: The activities of GST and G-6-PD, as well as the content of GSH decreased significantly with SO2 increased. The content of MDA increased evidently with SO2 increased., Conclusion: SO2 can influence GSH oxidation-deoxidation system and cause DNA damage in male reproductive system of mice.

Gonadal primordial germ cells (PGCs) were isolated from 4.5-7.5-day-old chicken embryos. Factors influencing isolation and cloning of chicken PGCs were analyzed in this study. The results attained were as follows: Chicken PGCs proliferated fast in presence of 10% FBS. At primary culture, PGCs were co-cultured with the gonadal stromal cells. For subculture the chicken PGCs were plated with mitotically inactive feeder layer cells. Further research found that the PMEF (primary mice embryonic fibroblast) feeder cells were the most suitable for the growth of PGCs. When the cell culture medium was supplemented with LIF, FGF, SCF and IGF-I, the chicken PGCs were in the best condition. The chicken PGCs were easier to clone when isolated from 5.5-day-old embryonic gonads. In addition, the proper digestion time was 40s when PGCs colonies were passaged.