[Effects of Wp-PKC on gonadal development of Whitmania pigra]

Protein kinase C(PKC) is a kind of kinase which is widely involved in cell proliferation and development. PKC(Wp-PKC) in Whitmania pigra body belongs to classic PKC. In order to investigate the effect of Wp-PKC on the development of Wh. pigra germ cells, 17β-estradiol(17β-E2)(100 ng·mL~(-1)) and methyltestosterone(MT)(150 μg·L~(-1)), 150 μg·L~(-1)(MT)+0.5 mg·L~(-1) PKC, 0.5 mg·L~(-1) PKC inhibitor were added to Wh. pigra culture water, and no addition group(control group) was added, and the effects on the development of Wh. pigra germ cells and the expression of Wp-PKC were observed. The results showed that: Wp-PKC in male gonads was always higher than that in female gonads; MT promoted the development of male gonads in Wh. pigra, while the expression of Wp-PKC was significantly higher than that in the control; 17β-E2 promoted the development of female gonads in Wh. pigra and Wp-PKC expression significantly lower than that of the control; while the development of the female and male gonads in the PKC inhibitor group was inhibited, the expression of Wp-PKC was significantly lower than that of the control. In summary, Wp-PKC may promote the development of Wh. pigra, especially the development of male gonads.

Uptake, accumulation, and translocation mechanisms of steroid estrogens in plants

Applying sewage sludge or animal manure onto agricultural land can result in estrogen pollution, which increases the risk of human exposure to steroid estrogens (SEs) via the food chain. However, the uptake and accumulation mechanism of SEs by plants is still unclear. In this study, the uptake, accumulation, and translocation of 17β-E2, a representative SE, were investigated through a series of wheat hydroponic experiments. Various inhibitors were applied to explore the uptake pathways of 17β-E2 by wheat. In addition, the effects of exposure concentrations, coexisting 17α-ethynylestradiol (EE2) and plant properties on the uptake of 17β-E2 were examined. The results indicated that the accumulation of 17β-E2 in wheat roots mainly resulted from adsorption and active uptake that involved aquaporins and anion channels transport. The chlorophyll and protein contents of plants were positively correlated with the uptake of 17β-E2, whereas competitive inhibition occurred when 17β-E2 and EE2 coexisted in the same solution. Nevertheless, the results of a split-root experiment showed that 17β-E2 absorbed by wheat could further migrate in plant via long-distance transport and ultimately was discharged from plants, suggesting that 17β-E2 was still at risk of being released even though it had been absorbed by plants. These results could provide valuable insights into the risk assessment and risk control of the uptake of SEs by plants.

Synergistic effect between LH and estrogen in the acceleration of cumulus expansion via GPR30 and EGFR pathways

The estrogen membrane receptor GPR30 (also known as G-protein coupled receptor 30) has recently been shown to be involved in the regulation of oocyte maturation and cumulus expansion. However, whether GPR30 expression is regulated by gonadotropin stimulation and how it participates in the regulation of the maturation process is still not clear. In this study, we explored the mechanism underlying the synergy between luteinizing hormone and 17β-estradiol (17β-E₂) to improve the epidermal growth factor (EGF) response in cumulus oocyte complexes (COCs) during oocyte maturation in mice. The expression and distribution of GPR30, EGFR, and EGF-like growth factors were examined by real-time quantitative PCR, western blot, and immunofluorescence staining. Lyso-Tracker Red labeling was performed to detect the lysosomal activity in follicle granular cells (FGCs). Cumulus expansion of COCs was evaluated after in vitro maturation for 16 h. We found that EGF-like growth factors transmit LH signals to increase GRP30 levels by inhibiting protein degradation in lysosomes. Meanwhile, 17β-E₂ stimulates the GPR30 signaling pathway to increase EGF receptor levels, enhancing the response ability of EGF signaling in COCs and thus promoting cumulus expansion. In conclusion, our study reveals the synergistic mechanism between LH and estrogen in the regulation of cumulus expansion during oocyte maturation process.

17β-estradiol attenuates rat articular chondrocyte injury by targeting ASIC1a-mediated apoptosis

Epidemiological evidence suggests that the etiology and pathogenesis of rheumatoid arthritis (RA) are closely associated with estrogen metabolism and deficiency. Estrogen protects against articular damage. Estradiol replacement therapy ameliorates local inflammation and knee joint swelling in ovariectomized models of RA. The mechanistic basis for the protective role of 17β-estradiol (17β-E2) is poorly understood. Acid-sensing ion channel 1a (ASIC1a), a sodium-permeable channel, plays a pivotal role in acid-induced articular chondrocyte injury. The aims of this study were to evaluate the role of 17β-E2 in acid-induced chondrocyte injury and to determine the effect of 17β-E2 on the level and activity of ASIC1a protein. Results showed that pretreatment with 17β-E2 attenuated acid-induced damage, suppressed apoptosis, and restored mitochondrial function. Further, 17β-E2 was shown to reduce protein levels of ASIC1a through the ERα receptor, to protect chondrocytes from acid-induced apoptosis, and to induce ASIC1a protein degradation through the autophagy-lysosomal pathway. Taken together, these results show that the use of 17β-E2 may be a novel strategy for the treatment of RA by reducing cartilage destruction through down-regulation of ASIC1a protein levels.

Identification and genome analysis of a novel 17β-estradiol degradation bacterium, Lysinibacillus sphaericus DH-B01

The natural estrogen 17β-estradiol (17β-E2) is a major endocrine disruptor. Accordingly, due to their frequent presence in global surface waters, prolonged exposure to estrogen-contaminated water may disrupt sexual development in animals. It has adverse effects on wildlife and humans. To date, the most effective strategy for estrogen removal from the environment is biodegradation using microorganisms. To this end, we isolated a strain of Lysinibacillus sphaericus, namely DH-B01, from a contraceptive factory in Beijing. The experimental results revealed that the bacterium has a high capacity to degrade estrogen, with a 17β-E2 degradation rate of about 97%, and produces the secondary metabolite estrone. In addition, a series of genes involved in steroid metabolism and stress response in L. sphaericus sp. DH-B01 were predicted, and several key genes with high similarity to those of other strains were subjected to sequence alignment to find their conserved regions. This is the first study of the ability of L. sphaericus strains to degrade estrogens and the degradation mechanism involved. This work advances the genomic study of estrogen-degrading strains and the study of bacterial estrogen degradation mechanisms. In this paper, a novel bacterial strain capable of degrading 17β-E2 was studied. L. sphaericus sp. DH-B01 can effectively degrade 17β-E2. During the degradation process, 17β-E2 can be gradually metabolized to a substance without estrogen activity. By analyzing the enzymatic reactions in the metabolic process, we found genes with high similarity to reported 17β-HSD. L. sphaericus sp. DH-B01 was found to degrade 17β-E2. There are many types of bacteria that are currently being studied for the degradation of estrogen, but L. sphaericus sp. DH-B01 is the only strain of L. sphaericus that has been shown to degrade estrogen. This work advances the genomic study of estrogen-degrading bacterial strains and the study of bacterial estrogen degradation mechanisms. Additionally, it explores the correlation between different L. sphaericus strains. The differences play an important role and further enrich the functionality and diversity of L. sphaericus strains. In subsequent studies, the specificity of L. sphaericus sp. DH-B01 can be applied to different environments for future environmental restoration.

[Effects of 17β-E2 on growth and gonad development of overwintering Whitmania pigra]

The present study was conducted to explores the effects of short-term addition of 17β-E2 on the growth,gonad development and internal quality of overwintering Whitmania pigra. Before overwintering,0. 0,1. 0,10. 0,25. 0,50. 0,100. 0 μg·L~(-1) of 17β-E2 were added to the aquaculture water for 6 weeks and then hibernated for 60 days. The changes of growth performance,gonad index,morphological structure of spermary( ovary),endogenous steroid hormones level and internal quality were measured. The results showed that the body weight,weight gain rate,specific growth rate,female gonad index,oocyte development and endogenous estrogen level of the leech increased first and then decreased with the increase of the concentration of exogenous 17β-E2,which were higher than those of the control group. The body weight,weight gain rate and specific growth rate of the leech at the concentration of 25 μg·L~(-1)17β-E2 were significantly higher than those of the other groups( P<0. 05),oocyte development and endogenous estrogen levels were significantly higher than those of other groups at the concentration of 50 μg·L~(-1)( P<0. 05). When the concentration of exogenous 17β-E2 was higher than 50 μg·L~(-1),the levels of male gonad index,spermatocyte development,endogenous androgen and progesterone were significantly inhibited( P< 0. 05). There was no significant difference in endogenous corticosteroid levels among the groups. In conclusion,short-term addition of exogenous 17β-E2 of 10-25 μg·L~(-1) could promote the growth of overwintering leeches,oocyte development and antithrombin activity without inhibiting the development of male gonads.

Natural and synthetic estrogens in leafy vegetable and their risk associated to human health

Since the inception of global industrialization, the growth of steroid estrogens becomes a matter of emerging serious concern for the rapid population. Steroidal estrogens are potent endocrine-upsetting chemicals that are excreted naturally by vertebrates (e.g., humans and fish) and can enter natural waters through the discharge of treated and raw sewage. Steroidal estrogens in plants may enter the food web and become a serious threat to human health. We evaluated the uptake and accumulation of ethinylestradiol (EE2) and 17β-estradiol (17β-E2) in lettuce plants (Lactuca sativa) grown under controlled environmental condition over 21 days growth period. An effective analytical method based on ultrasonic liquid extraction (ULE) for solid samples and solid phase extraction (SPE) for liquid samples with gas chromatography-mass spectrometry (GC/MS) has been developed to determine the steroid estrogens in lettuce plants. The extent of uptake and accumulation was observed in a dose-dependent manner and roots were major organs for estrogen deposition. Unlike the 17β-E2, EE2 was less accumulated and translocated from root to leaves. For 17β-E2, the distribution in lettuce was primarily to roots after the second week (13%), whereas in leaves it was (10%) over the entire study period. The distribution of EE2 at 2000 μg L-1 in roots and leaves was very low (3.07% and 0.54%) during the first week and then was highest (12% in roots and 8% in leaves) in last week. Bioaccumulation factor values of 17β-E2 and EE2 in roots were 0.33 and 0.29 at 50 μg L-1 concentration as maximum values were found at 50 μg L-1 rather than 500 and 2000 in all observed plant tissues. Similar trend was noticed in roots than leaves for bioconcentration factor as the highest bioconcentration values were observed at 50 μg L-1 concentration instead of 500 and 2000 μg L-1 spiked concentration. These findings mainly indicate the potential for uptake and bioaccumulation of estrogens in lettuce plants. Overall, the estrogen contents in lettuce were compared to the FAO/WHO recommended toxic level and were found to be higher than the toxic level which is of serious concern to the public health. This analytical procedure may aid in future studies on risks associated with uptake of endocrine-disrupting chemicals in lettuce plants.