PI3K-Akt/LKB1-AMPK-mTOR-p70S6K/4EBP1 signaling pathways participate in the regulation of testis development and spermatogenesis: An update / 中华男科学杂志

Male infertility is closely associated with spermatogenesis disorders triggered by aberrant gene expression or abnormal signaling pathways in the testis. The mammalian target of rapamycin (mTOR) is a central regulator of cell metabolism, playing an important role in regulating cell proliferation, differentiation, translation, actin polymerization, cycle progression, energy metabolism, autophagy, and other cellular activities. PI3K-Akt and LKB1-AMPK, the two well-defined classic signal transduction pathways, regulate the expressions of mTOR and its downstream p70S6K/4EBP1 through different molecular pathways. Recent studies show that mTOR-p70S6K/4EBP1 signaling participates in the regulation of the proliferation and differentiation of testicular cells and spermatogenesis. This review focuses on the role of PI3K-Akt/LKB1- AMPK-mTOR signaling cascades in testis development and spermatogenesis, providing some new perspectives for the studies of the molecular mechanism underlying male sterility.

Action mechanism of p,p'-DDE and/or beta-BHC on JNK and MAPK signal transduction pathways in rat Sertoli cells / 中华男科学杂志

<p><b>OBJECTIVE</b>To study the action mechanism of p,p'-DDE and/or beta-BHC on JNK and MAPK signal transduction pathways in rat Sertoli cells in vitro.</p><p><b>METHODS</b>We cultured the Sertoli cells isolated from rat testicular tissues for 2 days in vitro, divided them into a control group incubated with DMSO and 3 case groups exposed to p,p'-DDE and / or beta-BHC at the final concentration of 10, 30, 50 micromol/L for 24 hours, and then detected the expression levels of JNK and c-jun mRNA by two-step RT-PCR.</p><p><b>RESULTS</b>Twenty-four hours after p,p'-DDE treatment, the grayscale values of JNK mRNA were 0.068 +/- 0.001, 0.164 +/- 0.002, 0.207 +/- 0.006 and 0.499 +/- 0.017, and those of c-jun mRNA were 0.122 +/- 0.002, 0.157 +/- 0.006, 0.218 +/- 0.007 and 0.289 +/- 0.004 respectively in the DMSO control and the 10, 30 and 50 micromol/L groups. The expressions of JNK and c-jun mRNA were elevated with increased concentration of p,p'-DDE, with significant differences between the control and the case groups (P < 0.05), and they were also significantly upregulated in the beta-BHC and p,p'-DDE + beta-BHC groups in a dose-dependent manner. The grayscale values of JNK mRNA in the p,p'-DDE, beta-BHC and p,p'-DDE + beta-BHC groups at the concentration of 10 micromol/L were 0.164 +/- 0.002, 0.149 +/- 0.003 and 0.178 +/- 0.004, and those of c-jun mRNA were 0.157 +/- 0.006, 0.131 +/- 0.004 and 0.172 +/- 0.002, respectively, both significantly higher in the combination group than in the former two (P < 0.05). And the same was the case with the 30 and 50 micromol/L concentrations.</p><p><b>CONCLUSION</b>Both p,p'-DDE and beta-BHC can enhance the expressions of JNK and c-jun in Sertoli cells, and their combination can produce even more obvious effect.</p>

Effects of p,p'-DDE and beta-BHC on the apoptosis of Sertoli cells in vitro / 中华预防医学杂志

<p><b>OBJECTIVE</b>To explore the effects of p,p'-DDE and beta-BHC on the apoptosis of Sertoli cells in vitro via activation of Caspase.</p><p><b>METHODS</b>Sertoli cells were treated in vitro for 24 hours with a serial concentrations of p,p'-DDE (10, 30 and 50 micromol/L), beta-BHC (10, 30 and 50 micromol/L) and p,p'-DDE + beta-BHC (10, 30 and 50 micromol/L). The inhibitory group was first treated with 100 micromol/L Caspase-3 inhibitor Ac-DEVD-CHO treating for 2 hours before 50 micromol/L p, p'-DDE + 50 micromol/L beta-BHC 24 hours-treatment. The vitality of Sertoli cells was determined by MTT and the apoptosis rate was measured by AO/EB double fluorescence staining. The expressions of Caspase-3, Caspase-8 and Caspase-9 were determined by RT-PCR.</p><p><b>RESULTS</b>Average optical density (A) values were 0.498 +/- 0.039, 0.481 +/- 0.065, 0.397 +/- 0.032 and 0.286 +/- 0.049 in p,p'-DDE groups (10, 30, 50 and 70 micromol/L), and 0.518 +/- 0.103, 0.490 +/- 0.060, 0.454 +/- 0.054 and 0.302 +/- 0.030 in beta-BHC groups (10, 30, 50 and 70 micromol/L). In the mixture-treated groups (10, 30 and 50 micromol/L), the average A values were 0.483 +/- 0.048, 0.473 +/- 0.058 and 0.337 +/- 0.052. Compared with the solvent control group (0.527 +/- 0.022) , 50 micromol/L group of p, p'-DDE, beta-BHC or their mixture caused a significant decrease of Sertoli cell viability (t values were 4.599, 2.716, 6.537 respectively, P < 0.05). AO/EB double fluorescence staining analysis showed that apoptosis rates of Sertoli cells were significantly increased with all treated groups. The expressions of Caspase-3, Caspase-8 and Caspase-9 were upregulated as the concentrations of p,p'-DDE, beta-BHC and their mixture were increased.</p><p><b>CONCLUSION</b>p,p'-DDE, beta-BHC and their mixture could induce the apoptosis of Sertoli cells in vitro which was associated with activation of Caspase-3 mediated by cleavage of Caspase-8 and Caspase-9.</p>

Investigation on one-pot extraction of active ingredient group from Yupingfeng powder by HPLC / 中国中药杂志

The extraction of active ingredient group, i.e., prim-o-glucosylcimifugin, astragaloside, and 5-o-methylvisammiosode from Yupingfeng powder with one-pot method was studied in this work. A HPLC method was used to determine the content of each active constituent mentioned above in the extract. The influences of extraction temperature, time, volume percent of ethanol in water and its amount added on the content and yield of active ingredient group were investigated by orthogonal test. The experimental results showed that the optimized extraction conditions were as follows: 1g of Yupingfeng powder was one-pot extracted for 4 hours at 80 degrees C with 90% ethanol as solvent, and the yield and content of active ingredient group were 0.16%, 0.53% respectively. The active ingredient group in Yupingfeng powder could be effectively one-pot extracted under the conditions above.

Inhibitory effects of selenium on telomerase activity and hTERT expression in cadmium-transformed 16HBE cells / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To investigate the effects of sodium selenite on telomerase activity and expression of hTERT mRNA in cadmium-transformed 16HBE cells.</p><p><b>METHODS</b>Telomerase activity and expression of genes were measured after cultured cadmium-transformed 16HBE cells were exposed to sodium selenite at different doses (0.625, 1.25, 2.50, 5.00 micromol/L) for 24 hours.</p><p><b>RESULTS</b>Selenium decreased telomerase activity in cadmium-transformed 16HBE cells. There existed an obvious dose-effect relationship between the selenium concentration and these changes. The expression of hTERT and c-myc mRNA also decreased but the expression of mad1 mRNA increased after exposure to selenium for 24 hours. No difference was found in expression of hTRF1 and hTRF2 mRNA after incubated with sodium selenite for 24 hours, compared with control group.</p><p><b>CONCLUSION</b>Selenium inhibits telomerase activity by decreasing hTERT and c-myc mRNA expression and increasing mad1 mRNA expression in cadmium-transformed 16HBE cells and selenium concentration is significantly correlated with these changes.</p>

Effects of p,p'-dDE on the expression of androgen-binding protein, transferrin and inhibin B mRNA in rat sertoli cells / 中华男科学杂志

<p><b>OBJECTIVE</b>To explore effects of p, p'DDE on the expression of androgen binding protein (ABP), transferrin (Tf) and inhibin B (INH B) mRNA in testis Sertoli cells of Sprague Dawley rats.</p><p><b>METHODS</b>A method has been set up to obtain a large number of viable Sertoli cells from SD rats of 18-20 days of age. With a series of concentration p,p'-DDE (10, 30, and 50 micromol/L) co-incubating the Sertoli cells in vitro, the expression of ABP, Tf and INH B mRNA were determined by RT-PCR.</p><p><b>RESULTS</b>a) With increase of the incubated p, p'-DDE, the expression of ABP mRNA in Sertoli cells went up while that of Tf and INH B dropped in a dose-dependent manner (P < 0. 05). b) The correlation analysis among ABP, Tf and INH B showed that negative relationships were found between ABP and Tf or INH B, respectively (r = - 0. 391 3, P = 0. 032 5; r = - 0.235 2, P = 0.0158), and that positive correlation was indicated between Tf and INH B (r =0.4516, P =0.0047).</p><p><b>CONCLUSION</b>p,p'-DDE is a reproductive toxicant which disrupts the transcription of ABP, Tf and INH B in rat Sertoli cells so as to result in reproductive dysfunction.</p>

Effects of selenium on expression of TERT, c-Myc and p53 induced by cadmium in rat liver / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To study the effects of sodium selenite on expression of telomerase reverse transcriptase mRNA, c-Myc and p53 induced by cadmium chloride in rat liver.</p><p><b>METHODS</b>Male SD rats were divided randomly into 6 groups, each group had 5 animals. The groups comprised the control group, Se group (5 micromol/kg sodium selenite), 5 micromol/kg cadmium chloride group, 10 micromol/kg cadmium chloride group, Se (5 micromol/kg sodium selenite) + 5 micromol/kg cadmium chloride group, Se (5 micromol/kg sodium selenite) + 10 micromol/kg cadmium chloride group. After 48 hours of the first injection, the expression of TERT mRNA was measured with RT-PCR and c-Myc, and p53 proteins were measured by immunohistochemistry method.</p><p><b>RESULTS</b>Compared with control group, the expression of TERT was increased in 5 micromol/kg Cd group and 10 micromol/kg Cd group, c-Myc protein was increased in 10 micromol/kg Cd group, and the expression of p53 protein was increased in 5 micromol/kg group and 10 micromol/kg Cd group. TERT expression in Se + 10 micromol/kg Cd group was lower than that of 10 micromol/kg Cd group significantly. c-Myc protein was decreased in Se + 10 micromol/kg Cd group compared with 10 micromol/kg Cd group. p53 protein of Se + 5 micromol/kg Cd group and Se + 10 micromol/kg Cd group were decreased significantly compared with 5 micromol/kg Cd group and 10 micromol/kg Cd group respectively.</p><p><b>CONCLUSION</b>The cadmium at the doses of between 5 and 10 micromol/kg can activate TERT and up-regulate c-Myc and p53 proteins. The selenium at the dose of 5 micromol/kg has the antagonistic effect on expression of TERT, c-Myc and p53 induced by cadmium in rat liver.</p>

Effects of fluoride on lipid peroxidation, DNA damage and apoptosis in human embryo hepatocytes / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To investigate the effects of fluoride on lipid peroxidation, DNA damage and apoptosis in human embryo hepatocyte L-02 cells.</p><p><b>METHODS</b>Lipid peroxide (LPO) level, reduced glutathione (GSH) content, DNA damage, apoptosis, and cell cycle analysis were measured after in vitro cultured L-02 cells were exposed to sodium fluoride at different doses (40 microg/mL, 80 microg/mL, and 160 microg/mL) for 24 hours.</p><p><b>RESULTS</b>Fluoride caused an increase of LPO levels and a decrease of GSH content in L-02 cells. There appeared to be an obvious dose-effect relationship between the fluoride concentration and the observed changes. Fluoride also caused DNA damage and apoptosis and increased the cell number in S phase of cell cycle in the cells tested. There was a statistically significant difference in DNA damage and apoptosis when comparing the high dose of fluoride treated cells with the low dose of fluoride treated cells.</p><p><b>CONCLUSION</b>Fluoride can cause lipid peroxidation, DNA damage, and apoptosis in the L-02 cell experimental model and there is a significant positive correlation between fluoride concentration and these pathological changes.</p>

Study on the production condition of extraction in combination hydrolysis in situ for isolating diosgenin / 中国中药杂志

<p><b>OBJECTIVE</b>To study the production technology of extraction in combination hydrolysis in situ for isolating diosgenin from Dioscorea nipponica by orthogonal design.</p><p><b>METHOD</b>The optimum production conditions were investigated with the recovery of diosgenin as an index by extraction in combination hydrolysis in situ, and were compared with the traditional method.</p><p><b>RESULT</b>Extraction in combination hydrolysis in situ conducted in 1.5 mol x L(-1) sulfuric acid of water containing 75% isopropanol at 100 degrees C for 4.5 h could get higher recovery of diosgenin than traditional methods.</p><p><b>CONCLUSION</b>This production technology can get higher recovery of diosgenin, and it is simple, time and money saving.</p>

Effects of Selenium and Zinc on the Absorption, Excretion and Accumulation of Fluoride in Rats / 环境与健康杂志

ve To investigate the effects of selenium and zinc on the absorption, excretion and accumu-lation of fluoride in rats. Methods The contents of fluoride in serum, excrement, urine and bone were determined in Wistar rats drinking distilled water containing 100 mg/L NaF and orally perfused jointly with 0.1 mg/(kg? d) Na2SeO3 and/or 14.8 mg/(kg?d) ZnSO4 one time per two days continuously for 90 days. Results Na2SeO3 and/or ZnSO4 could increase the concentration of fluoride in urine, decrease the concentration of fluoride in serum and the content of fluoride in bone of rats. Exposure to ZnSO4 and joint exposure to Na2SeO3 and ZnSO4 could increase the content of fluoride in excrement. Conclusion ZnSO4 could inhibit the absorption of fluoride in intestine, Na2SeO3 and /or ZnSO4 could promote the excretion of urine fluoride and restrain the accumulation of fluoride in bone of rats.