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Yu S, Liu Z, Lyu JM, Guo CM, Yang XY, Jiang P, Wang YL, Hu ZY, Sun MH, Li Y, Chen LH, Su BL. Engineering surface framework TiO 6 single sites for unprecedented deep oxidative desulfurization. Natl Sci Rev 2024; 11:nwae085. [PMID: 38577670 PMCID: PMC10989657 DOI: 10.1093/nsr/nwae085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Revised: 02/14/2024] [Accepted: 03/05/2024] [Indexed: 04/06/2024] Open
Abstract
Catalytic oxidative desulfurization (ODS) using titanium silicate catalysts has emerged as an efficient technique for the complete removal of organosulfur compounds from automotive fuels. However, the precise control of highly accessible and stable-framework Ti active sites remains highly challenging. Here we reveal for the first time by using density functional theory calculations that framework hexa-coordinated Ti (TiO6) species of mesoporous titanium silicates are the most active sites for ODS and lead to a lower-energy pathway of ODS. A novel method to achieve highly accessible and homogeneously distributed framework TiO6 active single sites at the mesoporous surface has been developed. Such surface framework TiO6 species exhibit an exceptional ODS performance. A removal of 920 ppm of benzothiophene is achieved at 60°C in 60 min, which is 1.67 times that of the best catalyst reported so far. For bulky molecules such as 4,6-dimethyldibenzothiophene (DMDBT), it takes only 3 min to remove 500 ppm of DMDBT at 60°C with our catalyst, which is five times faster than that with the current best catalyst. Such a catalyst can be easily upscaled and could be used for concrete industrial application in the ODS of bulky organosulfur compounds with minimized energy consumption and high reaction efficiency.
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Lyu JM, Yu S, Liu Z, Du HY, Sun MH, Guo CM, Wang YL, Li Y, Chen LH, Su BL. Synergistic effect of K and Zn on Fe-based catalysts for efficient CO 2 hydrogenation. Dalton Trans 2024; 53:2526-2533. [PMID: 38226637 DOI: 10.1039/d3dt03913g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2024]
Abstract
Excessive emission of CO2 into the atmosphere has severely impacted the global ecological environment. Converting CO2 into valuable chemicals and fuels is of great significance for sustainable development. However, low activity and undesirable selectivity often result from the inherent inertness of CO2. Herein, K- or/and Zn-modified Fe-based catalysts were prepared by an incipient-wetness impregnation method for CO2 hydrogenation via a cascade reaction. The results indicate that K species exist as K2O while Zn species exist as ZnFe2O4. In the CO2 hydrogenation pathway, K2O facilitates the adsorption of CO2 and restrains the adsorption of H2, accelerating the transformation of CO2 into C2-C4 olefins rather than paraffins while Zn species promote the dispersion of Fe species, leading to improved activity. Synergistically, a K- and Zn-modified Fe-based catalyst (2Zn-10K-Fe/Al) shows excellent catalytic CO2 hydrogenation activity, achieving a CO2 conversion of 77% which is 1.8 times that (42%) of the unmodified Fe-based catalyst (Fe/Al). Our catalyst also shows a significantly promoted selectivity to C2-C4 olefins of 17% in comparison with the Fe/Al catalyst (0%). It is envisioned that such a binary effect of elements might contribute to the low-cost and industrial production of Fe-based catalysts for selective CO2 conversion.
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Yu S, Liu Z, Lyu JM, Guo CM, Wang YL, Hu ZY, Li Y, Sun MH, Chen LH, Su BL. Intraparticle ripening to create hierarchically porous Ti-MOF single crystals for deep oxidative desulfurization. Dalton Trans 2023; 52:12244-12252. [PMID: 37593831 DOI: 10.1039/d3dt01731a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/19/2023]
Abstract
The catalytic oxidative desulfurization (ODS) technique is able to remove sulfur compounds from fuels, conducive to achieving deep desulfurization for the good of the ecological environment. Ti-based metal-organic frameworks (Ti-MOFs) possessing good affinity to organic reactants and considerable numbers of Ti active sites are promising catalysts for ODS. However, current Ti-MOFs suffer from severe diffusion limitations caused by the size mismatch between sole micropores and bulky sulfur compounds, leading to poor ODS performance. Here, a facile method of intraparticle ripening without any additive is developed to obtain hierarchically meso-microporous Ti-MIL-125 single crystals (Meso-Ti-MIL-125) for the first time. Such Meso-Ti-MIL-125 shows a BET surface area of 1401 m2 g-1 and a mesoporous volume that is 1.7 times as high as that of the conventional Ti-MIL-125. Our novel Meso-Ti-MIL-125 exhibits excellent catalytic performance in the ODS of a series of bulky thiophenic sulfur compounds, completely removing benzothiophene (BT), dibenzothiophene (DBT), and 4,6-dimethyldibenzothiophene (DMDBT) from model fuels, which is, respectively, 2.4 times, 1.5 times, and 6.7 times higher than the removal achieved with conventional Ti-MIL-125. Such a facile synthetic strategy is envisioned to be applied in many kinds of crystalline materials, such as zeolites, for industrial production.
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Guo CM, Dai YB, Geng J, Li H, Dong YY, Wang ZQ, Wang JL. [Correlation between the primary tumor size of endometrial carcinoma and lymph node metastasis and recurrence]. ZHONGHUA FU CHAN KE ZA ZHI 2021; 56:264-270. [PMID: 33902238 DOI: 10.3760/cma.j.cn112141-20200923-00730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To investigate the clinical significance of the primary tumor size in patients with endometrial carcinoma (EC). Methods: A total of 385 patients with EC admitted to Peking University People's Hospital from January 2006 to December 2016 with complete follow up data were selected, whose tumor size data before biopsy were retrospectively studied. Results: (1) The mean diameter of the primary tumor was (3.6±1.8) cm (range: 1-15 cm). And 48 cases were 0-<2 cm, 78 cases were 2-<3 cm, 92 cases were 3-<4 cm, 73 cases were 4-<5 cm, 94 cases were ≥5 cm. The diameter of the tumor was associated with age <60 years old, premenopause, CA125≥35 kU/L, non-parturition, poor differentiation, stage Ⅲ-Ⅳ, depth of myometrial infiltration ≥1/2, cervical interstitial involvement, adnexal metastasis and lymph node metastasis (all P<0.05), but not associated with body mass index, hypertension, diabetes mellitus, pathology, lymph-vascular space invasion (all P>0.05). (2) Among the 334 patients underwent lymphadenectomy, 45 (13.5%, 45/334) cases with lymph node metastasis were observed. Stratified analysis showed that lymph node metastasis and recurrence rate of patients with EC gradually increased with the increase of tumor size (P<0.05). Adopting 2, 3, 4 and 5 cm as cut-off values of tumor size, there were significant differences in the rate of lymph node metastasis and recurrence among them observed (P<0.05), except for lymph node metastasis rate and recurrence rate when the cut-off value was 2 cm (P>0.05). (3) An receiver operating characteristic (ROC) curve analysis showed that a tumor diameter of 4.25 cm was the cut-off prognostic value to predict lymph node metastasis and recurrence of EC. Conclusions: Tumor diameter is significantly correlated with lymph node metastasis and recurrence in patients with EC. Tumor size should be considered in determining the scope of surgery and adjuvant therapy.
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Guo CM, Liu SQ, Sun MZ. miR-429 as biomarker for diagnosis, treatment and prognosis of cancers and its potential action mechanisms: A systematic literature review. Neoplasma 2019; 67:215-228. [PMID: 31884798 DOI: 10.4149/neo_2019_190401n282] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Accepted: 07/01/2019] [Indexed: 11/08/2022]
Abstract
miR-429 is a member of miR-200 family. Accumulated evidence has indicated that miR-429 dysregulation is involved in the epithelial-mesenchymal transition (EMT), progression, development, invasion, metastasis, apoptosis and drug resistance of a variety of cancers. miR-429 might specifically function either as a tumor suppressor or promoter candidate for certain cancers depending on the particular types of tumor cells/tissues. miR-429 appears to have a tumor-suppression role in renal cell carcinoma (RCC), breast cancer (BC), gastric carcinoma (GC), glioblastoma (GBM), esophageal cancer (EC), osteosarcoma, oral squamous cell carcinoma (OSCC), cervical cancer (CC), pancreatic cancer, tongue squamous cell carcinoma (TSCC), nephroblastoma, nasopharyngeal carcinoma (NPC) and soft tissue sarcomas. On the other hand, miR-429 has a tumor-promotion role in endometrial cancer (EmCa), prostate cancer (CaP) and lung cancer (LC). However, miR-429 shows paradoxical role in colorectal cancer (CRC), hepatocellular carcinoma (HCC), bladder cancer and ovarian cancer (OC). This article summarizes the associations between miR-429 and malignant tumors as well as potential action mechanisms. miR-429 has a potential to be used in the future as a biomarker for the diagnosis, treatment and prognosis of certain cancers.
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Wang AP, Liu L, Gu LL, Wu S, Guo CM, Feng Q, Xia WL, Yuan C, Zhu SY. Expression of duck hepatitis A virus type 1 VP3 protein mediated by avian adeno-associated virus and its immunogenicity in ducklings. Acta Virol 2019; 63:53-59. [PMID: 30879313 DOI: 10.4149/av_2019_104] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The avian adeno-associated virus (AAAV) is a replication-defective nonpathogenic virus that has been proved to be useful as a viral vector in gene delivery. In this study, the feasibility of AAAV for transgenic expression of duck hepatitis A virus (DHAV) VP3 structural protein and its ability to induce protective immunity in ducklings was assessed. The recombinant AAAV (rAAAV-VP3) expressing the VP3 protein was prepared by co-infection of Sf9 cells with recombinant baculovirus (rBac-VP3) containing VP3 gene flanked by inverted terminal repeats (ITRs) of AAAV and the other two recombinant baculovirus expressing AAAV functional and structural genes, respectively. The generation of rAAAV-VP3 was demonstrated by electron microscopy, immunofluorescence assay, and western blot analysis. One day old ducklings were inoculated with rAAAV-VP3 or commercial attenuated vaccine and then challenged with DHAV-1 strain SH two weeks post vaccination. Anti-DHAV-1 antibodies were detected in all vaccinated groups by ELISA, and the titers between the rAAAV-VP3 group and the attenuated vaccine group were not statistically significant. Real time RT-PCR analysis showed that the virus copy numbers in the livers of the PBS control group were significantly higher than that of the rAAAV-VP3 and attenuated vaccine groups. In conclusion, we demonstrated that the VP3 expression mediated by rAAAV in ducklings could induce protective immunity against DHAV challenge, and this could be a candidate vaccine for the control of duck viral hepatitis. Keywords: avian adeno-associated virus; duck hepatitis A virus; VP3 gene; immunogenicity.
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Huang B, Chen FG, Zhuang J, Zheng WC, Zhu WY, Zhang QC, Wang SH, Guo CM, Xie CM. [Primary tracheal malignant glomus tumor with lung metastasis diagnosed by pathological analysis: a case report and literature review]. ZHONGHUA JIE HE HE HU XI ZA ZHI = ZHONGHUA JIEHE HE HUXI ZAZHI = CHINESE JOURNAL OF TUBERCULOSIS AND RESPIRATORY DISEASES 2019; 49:697-702. [PMID: 28910916 DOI: 10.3760/cma.j.issn.1001-0939.2017.09.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Objective: To study the clinical manifestations, pathological features, diagnosis, differential diagnosis, treatment and prognosis of primary tracheobronchial or pulmonary malignant glomus tumor (MGT). Methods: A case of primary tracheal MGT with lung metastasis diagnosed by pathological analysis admitted to Affiliated Shantou Hospital of Sun Yat-sen University in May. 2015 was analyzed, and the related literatures were reviewed. We searched databases including PubMed, Embase, Ovid, Cochrane, Wanfang and Chinese National Knowledge infrastructure (CNKI), using the keyword "tracheal or bronchial or pulmonary malignant glomus tumor" from Jan. 1975 to Dec. 2016. Results: A 47 year-old male patient was admitted to the hospital because of cough, chest tightness and shortness of breath for 3 days. The chest CT showed a soft tissue mass with a diameter of 2.5 cm in the lower tracheal segment, and the lumen was narrowed. Meanwhile, multiple nodular opacities were shown in both lungs. The admission diagnosis was thyroid cancer with multiple metastases of lung. Electronic bronchoscopic airway tumor ablation and cryotherapy were performed, and then the biopsy of the tumor was conducted and the pathological study confirmed the diagnosis of primary tracheal MGT. After 1 month, the tracheal tumor recurred. Then, electronic bronchoscopic airway tumor ablation and cryotherapy were performed again. The patient declined further therapy such as radiotherapy or chemotherapy and died one month later. A total of 14 literatures including 15 cases were retrieved from databases. In addition of this case, a total of 16 cases were analyzed, including 9 males, 7 females. Age of onset ranged from 9 to 74 years, and the average age was 49 years. These patients' chest CT showed airway mass or lung space occupying lesions, and the clinical manifestations were nonspecific. Conclusions: Primary MGT in trachea, bronchus or lung is a rare disease, which is easy to be misdiagnosed or to miss diagnosis. The final diagnosis depends on pathological morphology, and the main treatment is lobectomy or tracheal segment resection surgery. Due to its high invasiveness, local recurrence and metastasis may occur easily. The primary MGT in trachea, bronchus or lung is of poor prognosis.
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Wang AP, Liu L, Gu LL, Guo CM, Wu S, Feng Q, Xia WL, Wu Z, Zhu SY. Protection against duck hepatitis a virus type 1 conferred by a recombinant avian adeno-associated virus. Poult Sci 2019; 98:112-118. [PMID: 30053293 DOI: 10.3382/ps/pey325] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Accepted: 06/29/2018] [Indexed: 11/20/2022] Open
Abstract
The avian adeno-associated virus (AAAV) has been proved to be an efficient gene transfer vector for human gene therapy and vaccine research. In this experiment, an AAAV-based vaccine was evaluated for the development of a vaccine against duck hepatitis a virus type 1 (DHAV-1). The major capsid VP1 gene was amplified and subcloned into pFBGFP containing the inverted terminal repeats of AAAV, and then the recombinant baculovirus rBac-VP1 was generated. The recombinant AAAV expressing the VP1 protein (rAAAV-VP1) was produced by co-infecting Sf9 cells with rBac-VP1 and the other 2 baculoviruses containing AAAV functional genes and structural genes respectively, and confirmed by electron microscopy, Western blotting and immunofluorescence assays. Quantitative real-time PCR revealed that the titer of rAAAV-VP1 was about 9 × 1012 VG/mL. Immunogenicity was studied in ducklings. One day ducklings were injected intramuscularly once with rAAAV-VP1. Serum from rAAAV-VP1-vaccinated ducklings showed a systemic immune response evidenced by VP1-specific enzyme-linked immunosorbent assay and virus neutralization test. Furthermore, all ducklings inoculated with rAAAV-VP1 were protected against DHAV-1 challenge. The data of quantitative real-time RT-PCR from livers of challenged ducklings also showed that the level of virus copies in rAAAV-VP1 group was significantly lower than that of the PBS group. Collectively, these results demonstrate that the AAAV-based vaccine is a potential vaccine candidate for the control of duck viral hepatitis.
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Wang AP, Wang YJ, Wu S, Zuo WY, Guo CM, Hong WM, Zhu SY. Study on the expression of human lysozyme in oviduct bioreactor mediated by recombinant avian adeno-associated virus. Poult Sci 2017; 96:2447-2453. [PMID: 28339926 DOI: 10.3382/ps/pex029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Accepted: 01/08/2017] [Indexed: 11/20/2022] Open
Abstract
Due to its antimicrobial properties and low toxicity, human lysozyme (hLYZ) has broad application in the medical field and as a preservative used by the food industry. However, limited availability hinders its widespread use. Hence, we constructed a recombinant avian adeno-associated virus (rAAAV) that would specifically express hLYZ in the chicken oviduct and harvested hLYZ from the egg whites of laying hens. The oviduct-specific human lysozyme expression cassette flanked by avian adeno-associated virus (AAAV) inverted terminal repeats (ITRs) was subcloned into the modified baculovirus transfer vector pFBX, and then the recombinant baculovirus rBac-ITRLYZ was generated. The recombinant avian adeno-associated virus was produced by co-infecting Sf9 cells with rBac-ITRLYZ and the other 2 baculoviruses containing AAAV functional genes and structural genes, respectively. Electron microscopy and real-time PCR revealed that the recombinant viral particles were generated successfully with a typical AAAV morphology and a high titer. After one intravenous injection of each laying hen with 2 × 1011 viral particles, oviduct-specific expression of recombinant human lysozyme (rhLYZ) was detected by reverse transcription-PCR. The expression level of rhLYZ in the first wk increased to 258 ± 11.5 μg/mL, reached a maximum of 683 ± 16.4 μg/mL at the fifth wk, and then progressively declined during the succeeding 7 wk of the study. Western blotting indicated that the oviduct-expressed rhLYZ had the same molecular weight as the natural enzyme. These results indicate that an efficient and convenient oviduct bioreactor mediated by rAAAV has been established, and it is useful for production of other recombinant proteins.
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Huang WJ, Wu LJ, Min ZC, Xu LT, Guo CM, Chen ZP, Lou XJ, Xu B, Lv BD. Interleukin-6 -572G/C polymorphism and prostate cancer susceptibility. GENETICS AND MOLECULAR RESEARCH 2016; 15:gmr7563. [PMID: 27706719 DOI: 10.4238/gmr.15037563] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Strong evidence suggests that cancer-associated inflammation promotes tumor growth and progression, and interleukin-6 (IL6) is an important modulator of inflammation. However, the roles of IL6 and mutations of its corresponding gene in prostate cancer have not been clearly documented. We retrieved data from the Oncomine database concerning IL6 expression in prostate cancer and its role in prostate-specific antigen (PSA) recurrence. We also performed a case-control study of the IL6 -572G/C polymorphism (rs1800796) in 236 sporadic prostate cancer patients and 256 healthy controls from a southern Han Chinese population. Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated to assess the association between rs1800796 and prostate cancer susceptibility. A dual-luciferase reporter assay was used to test the transcriptional activity of the IL6 promoter G and C alleles. IL6 was overexpressed in prostate cancer tissues compared to normal tissues, especially in those with higher Gleason scores. Moreover, elevated IL6 expression was associated with high PSA recurrence rate in Oncomine data. Our case-control study demonstrated that compared with the -572C allele, the -572G allele conferred a borderline increased risk of prostate cancer (OR = 1.31, 95%CI = 0.99-1.74, P = 0.061). This was more pronounced in the subgroup of individuals having never smoked (OR = 1.85, 95%CI = 1.07-3.22). Moreover, the G allele showed increased activity relative to the C allele in the dual-luciferase reporter assay. Our results suggest that the -572G/C polymorphism may be associated with IL6 expression, which in turn plays a role in prostate cancer development.
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Guan ZX, Wei DY, Guo CM, Liu HM. [A Case report of rare recurrent multiple skin cancer nodules in the radiation field after radiotherapy for cervical cancer]. ZHONGHUA ZHONG LIU ZA ZHI [CHINESE JOURNAL OF ONCOLOGY] 2016; 38:92. [PMID: 26899326 DOI: 10.3760/cma.j.issn.0253-3766.2016.02.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Guo CM, Kasaraneni N, Sun K, Myatt L. Cross talk between PKC and CREB in the induction of COX-2 by PGF2α in human amnion fibroblasts. Endocrinology 2012; 153:4938-45. [PMID: 22919060 PMCID: PMC3512005 DOI: 10.1210/en.2012-1441] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Compelling evidence indicates a crucial role of prostaglandin F2α (PGF2α) in parturition. Both the maternal and fetal sides of the fetal membranes synthesize PGF2α, which exerts effects via the prostaglandin F2α receptor (FP) that is coupled to the activation of protein kinase C (PKC). Cyclooxygenase-2 (COX-2) catalyzes the rate-limiting step of the inducible synthesis of prostaglandin. Although activation of PKC is known to induce COX-2 expression, it is not clear whether PGF2α can induce COX-2 via FP receptor-coupled PKC activation. COX-2 promoter carries a cAMP-response element (CRE) and phosphorylation of CRE binding protein 1 (CREB1) is associated with COX-2 expression in human amnion fibroblasts. We demonstrated that human amnion fibroblasts produced PGF2α and expressed FP receptor. PGF2α increased COX-2 expression and CREB1 phosphorylation, which could be blocked by either the FP receptor antagonist AL8810 or PKC inhibitor Ro31-7549. The PKC activator, phorbol-12-myristate-13-acetate (PMA), could mimic the induction of COX-2 and CREB1 phosphorylation. The induction of COX-2 by PGF2α and PMA could be attenuated by the small interfering RNA-mediated knockdown of CREB1 expression or overexpressing dominant-negative CREB1. A chromatin immunoprecipitation assay showed that the binding of CREB1 to the COX-2 promoter was increased by PGF2α and PMA in amnion fibroblasts. In conclusion, we provide evidence that PGF2α induces COX-2 expression via the FP receptor and phosphorylates CREB1 by PKC, thus increasing CREB1 binding to the COX-2 promoter and the expression of COX-2 in human amnion fibroblasts. This feed-forward loop may be crucial for the production of prostaglandins in the fetal membranes prior to the onset of labor.
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Li JN, Ge YC, Yang Z, Guo CM, Duan T, Myatt L, Guan H, Yang K, Sun K. The Sp1 transcription factor is crucial for the expression of 11beta-hydroxysteroid dehydrogenase type 2 in human placental trophoblasts. J Clin Endocrinol Metab 2011; 96:E899-907. [PMID: 21411560 DOI: 10.1210/jc.2010-2852] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Overexposure of the fetus to glucocorticoids early in gestation is detrimental to fetal development. Glucocorticoid concentrations in the fetal circulation are kept low by 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2, encoded by HSD11B2) in the placental syncytiotrophoblasts. However, cytotrophoblasts, the progenitors of syncytiotrophoblasts, express low levels of 11β-HSD2. Here we studied the molecular mechanisms underlying 11β-HSD2 induction upon syncytialization. METHODS Freshly isolated human term placental cytotrophoblasts and in vitro differentiated syncytiotrophoblasts were examined to determine the methylation status of HSD11B2 promoter. The transcription factor responsible for 11β-HSD2 induction was identified by observing its expression upon syncytialization, the effect of its attenuation, and its binding to the HSD11B2 promoter. RESULTS 11β-HSD2 expression was markedly increased upon syncytialization in vitro. No methylation differences of HSD11B2 promoter were found between cytotrophoblasts and syncytiotrophoblasts. Expression of the transcription factor Sp1 was markedly induced during syncytialization and further increased by activation of the cAMP pathway, which correlated with 11β-HSD2 expression. Importantly, small interfering RNA-mediated knockdown of Sp1 expression or inhibition of Sp1 activity with mithramycin A markedly attenuated not only basal but also cAMP pathway-stimulated expression of 11β-HSD2 in the syncytiotrophoblasts. Stimulation of the cAMP pathway also increased the binding of Sp1 and RNA polymerase II to HSD11B promoter in syncytiotrophoblasts. Concomitantly, acetylation at histone H3K9 was increased whereas methylation at histone H3K9 was decreased. CONCLUSIONS 11β-HSD2 induction upon syncytialization is at least in part due to the increased expression of Sp1 upon activation of the cAMP pathway rather than the differential methylation of the HSD11B2 promoter.
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Ge YC, Li JN, Ni XT, Guo CM, Wang WS, Duan T, Sun K. Cross talk between cAMP and p38 MAPK pathways in the induction of leptin by hCG in human placental syncytiotrophoblasts. Reproduction 2011; 142:369-75. [PMID: 21562093 DOI: 10.1530/rep-11-0053] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Leptin produced by the placental syncytiotrophoblasts participates in a number of processes in pregnancy including implantation, proliferation of the cytotrophoblasts, and nutrient transfer across the placenta. Despite the functional significance of leptin in pregnancy, the regulation of leptin synthesis is poorly understood in human placental syncytiotrophoblasts. In this study, we investigated the role of endogenous human chorionic gonadotropin (hCG) in the regulation of leptin production as well as the underlying mechanism involving the cross talk between cAMP and p38 mitogen-activated protein kinase (MAPK) pathways. We found that neutralization of endogenous hCG with its antibody dose dependently decreased leptin mRNA level and secretion, whereas exogenous hCG increased leptin mRNA level and secretion. Activation of the cAMP pathway with dibutyryl cAMP (db cAMP) or forskolin recapitulated the stimulatory effect of hCG on leptin expression. Inhibition of protein kinase A with H89 not only reduced the basal leptin expression but also attenuated the induced leptin expression by hCG. Treatment of the syncytiotrophoblasts with db cAMP and hCG phosphorylated p38 MAPK. Inhibition of p38 MAPK with SB203580 not only reduced the basal leptin production but also attenuated the leptin-induced production by both hCG and db cAMP. These data suggest that endogenous hCG plays a significant role in maintaining leptin production in human placental syncytiotrophoblasts, and this effect involves a cross talk between cAMP and p38 MAPK pathways.
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Guo CM, Zhu XO, Ni XT, Yang Z, Myatt L, Sun K. Expression of progesterone receptor A form and its role in the interaction of progesterone with cortisol on cyclooxygenase-2 expression in amnionic fibroblasts. J Clin Endocrinol Metab 2009; 94:5085-92. [PMID: 19837932 DOI: 10.1210/jc.2009-0832] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Human amnion fibroblasts produce abundant prostaglandins toward the end of gestation, which is believed to be one of the major events leading to parturition. Glucocorticoids have been shown to up-regulate cyclooxygenase-2 (COX-2) expression, the crucial enzyme catalyzing prostaglandin synthesis, in human amnion fibroblasts. Although a major propregnancy hormone, the effect of progesterone and the associated progesterone receptor subtypes in the regulation of both basal and glucocorticoid-induced COX-2 expression in human amnion fibroblasts have not been resolved. METHODS AND RESULTS Cultured human amnion fibroblasts prepared from the fetal membranes at term pregnancy without labor mainly expressed the progesterone receptor A form (PRA). Inhibition of endogenous progesterone production with trilostane or knockdown of PRA expression with small interfering RNA significantly enhanced the glucocorticoid receptor (GR)-mediated COX-2 induction by cortisol, whereas overexpression of PRA attenuated the induction by cortisol. Co-immunoprecipitation assay revealed PRA in the GR protein complex. Although exogenous progesterone did not alter COX-2 expression under basal conditions, it attenuated cortisol-induced COX-2 expression at concentrations about 10- to 50-fold higher, which might be achieved by competition with cortisol for GR. CONCLUSIONS We demonstrated in this study that endogenous progesterone might counteract the induction of prostaglandin synthesis by cortisol via PRA transdominant repression of GR function, whereas high levels of progesterone might further inhibit the induction by cortisol via competitive binding to GR in human amnion fibroblasts. These inhibitory actions of progesterone and PRA on glucocorticoids and GR may partly explain the inconsistent effects of glucocorticoids on parturition in humans.
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Ni XT, Duan T, Yang Z, Guo CM, Li JN, Sun K. Role of human chorionic gonadotropin in maintaining 11beta-hydroxysteroid dehydrogenase type 2 expression in human placental syncytiotrophoblasts. Placenta 2009; 30:1023-8. [PMID: 19880179 DOI: 10.1016/j.placenta.2009.10.005] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2009] [Revised: 10/08/2009] [Accepted: 10/10/2009] [Indexed: 11/18/2022]
Abstract
Proper glucocorticoid exposure in utero is vital for normal fetal organ maturation, but excess glucocorticoids are detrimental to fetal growth and can even predispose the individuals to the high risk of having certain diseases in adulthood. The fetus is protected from 10 times higher maternal glucocorticoid levels by the placental enzyme 11beta-hydroxysteroid dehydrogenase 2 (11beta-HSD2), which converts biologically active cortisol to inactive cortisone. Thus it is of primary importance to understand how this enzyme is regulated. Activation of cAMP/PKA pathway is known to upregulate 11beta-HSD2 expression in placental syncytiotrophoblasts, however the endogenous hormones utilizing this pathway remain largely unknown. By using cultured human placental syncytiotrophoblasts, we demonstrated that inhibition of protein kinase A with H89 attenuated 11beta-HSD2 expression in the syncytiotrophoblasts, suggesting endogenous factors from the syncytiotrophoblasts using this pathway to maintain 11beta-HSD2 expression in the syncytiotrophoblasts. Neutralization of human chorionic gonadotropin (hCG) secreted by the syncytiotrophoblasts with hCG antibody decreased 11beta-HSD2 promoter activity, mRNA and protein expression as well as intracellular cAMP level, while treatment of the syncytiotrophoblasts with exogenous hCG increased 11beta-HSD2 expression, which was attenuated by H89. Furthermore, we found that cortisol increased both hCG expression and secretion. The up-regulation of 11beta-HSD2 expression by cortisol was significantly attenuated by co-treatment with hCG antibody or H89 in the syncytiotrophoblasts. In conclusion, hCG is an important paracrine or autocrine hormone maintaining 11beta-HSD2 expression and the up-regulation of 11beta-HSD2 expression by cortisol may be mediated in part by hCG in the syncytiotrophoblasts.
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MESH Headings
- 11-beta-Hydroxysteroid Dehydrogenase Type 2/genetics
- Antibodies, Monoclonal/immunology
- Antibodies, Monoclonal/pharmacology
- Cell Differentiation/physiology
- Chorionic Gonadotropin/pharmacology
- Chorionic Gonadotropin/physiology
- Chorionic Gonadotropin, beta Subunit, Human/genetics
- Colforsin/pharmacology
- Cyclic AMP/metabolism
- Cycloheximide/pharmacology
- Female
- Gene Expression/drug effects
- Gene Expression/genetics
- Gene Expression Regulation, Developmental/drug effects
- Gene Expression Regulation, Developmental/physiology
- Gene Expression Regulation, Enzymologic/drug effects
- Glycoprotein Hormones, alpha Subunit/genetics
- Humans
- Hydrocortisone/pharmacology
- Isoquinolines/pharmacology
- Placenta/cytology
- Pregnancy
- Promoter Regions, Genetic/drug effects
- Promoter Regions, Genetic/genetics
- Protein Kinase Inhibitors/pharmacology
- Signal Transduction/drug effects
- Signal Transduction/physiology
- Sulfonamides/pharmacology
- Trophoblasts/drug effects
- Trophoblasts/metabolism
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Zhu XO, Yang Z, Guo CM, Ni XT, Li JN, Ge YC, Myatt L, Sun K. Paradoxical stimulation of cyclooxygenase-2 expression by glucocorticoids via a cyclic AMP response element in human amnion fibroblasts. Mol Endocrinol 2009; 23:1839-49. [PMID: 19797430 DOI: 10.1210/me.2009-0201] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Human amnion fibroblasts produce abundant prostaglandins toward the end of gestation, which is one of the major events leading to parturition. In marked contrast to its well-described antiinflammatory effect, glucocorticoids have been shown to up-regulate cyclooxygenase-2 (COX-2) expression in human amnion fibroblasts. The mechanisms underlying this paradoxical induction of COX-2 by glucocorticoids have not been resolved. Using cultured human amnion fibroblasts, we found that the induction of COX-2 mRNA expression by cortisol was a glucocorticoid receptor (GR)-dependent process requiring ongoing transcription. Upon transfection of a COX-2 promoter-driven reporter gene into the amnion fibroblasts, cortisol stimulated the COX-2 promoter activity. This was abolished by mutagenesis of a cAMP response element (CRE) at -53 to approximately -59bp as well as by cotransfection of a plasmid expressing dominant-negative CRE-binding protein (CREB). The phosphorylation level of CREB-1 was significantly increased by cortisol treatment of the amnion fibroblasts, whereas the effect was attenuated either by the protein kinase A inhibitor H89 or the p38 -MAPK inhibitor SB203580. The induction of the COX-2 promoter activity and the phosphorylation of CREB-1 were also blocked by the GR antagonist RU486. Chromatin immunoprecipitation (ChIP) assay revealed that the binding of CREB-1 to the CRE of the COX-2 promoter was increased by cortisol treatment of the amnion fibroblasts. In conclusion, cortisol, via binding to GR, stimulated COX-2 expression by increasing phosphorylated CREB-1 binding to the CRE of the COX-2 gene. Cortisol may phosphorylate CREB-1 by activating either protein kinase A or p38-MAPK in the amnion fibroblasts.
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18
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Zhang ZG, Liu GW, Li XB, Li YF, Guo CM, Gao L, Wang HB, Xu SW, Wang Z. Measurement of milk D-3-hydroxybutyrate with a simple UV spectrophotometer method: an alternative assay method. Pol J Vet Sci 2009; 12:563-565. [PMID: 20169934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The measurement of D-3-hydroxybutyrate (D-BHBA) in milk samples is an important tool for diagnosis of subclinical/clinical ketosis in dairy cows. We describe a simple UV spectrophotometric method for measuring the concentration of D-BHBA in milk of dairy cows. From two herds, 119 milk samples were taken from dairy cows. The standard-curve equation was y = 0.2582x + 0.0269 (R2 = 0.9967). The assay was highly specific with a minimum detection limit of 0.01 mmol/L and measuring range of up to 5 mmol/L. The recovery was between 99.35% and 100.22% and repeatability was 99.8%. The comparison between the spectrophotometric method and the fluorometric method revealed a close correlation (r = 0.9939). These results show that the spectrophotometric method can be successfully used as an alternative method to measure D-BHBA content in milk.
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19
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Teoh LC, Yong FC, Guo CM. Congenital isolated upper limb hypertrophy with hand abnormality--a report of 2 cases. JOURNAL OF HAND SURGERY (EDINBURGH, SCOTLAND) 2001; 26:492-5. [PMID: 11560437 DOI: 10.1054/jhsb.2001.0643] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Two cases of congenital isolated hypertrophy of the left upper limb with different hand deformities are described. A 4-year-old girl had splayed fingers and an abducted thumb due to anomalous muscles. Excision of these muscles corrected the deformity. The other, an 8-year-old boy, had severe ulnar drift of the fingers (windblown-like hand). He had corrective osteotomies of the second and third metarcarpals and reconstruction of the collateral ligaments. The deformity was corrected and at the latest follow up there was with no recurrence of the deviation. Both cases regained good hand function.
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Guo CM. [Preliminary analysis on the causes of prevalent tuberculous meningitis in Heilungjiang province]. ZHONGHUA JIE HE HE HU XI ZA ZHI = ZHONGHUA JIEHE HE HUXI ZAZHI = CHINESE JOURNAL OF TUBERCULOSIS AND RESPIRATORY DISEASES 1988; 11:257-9, 317. [PMID: 3266104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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