Publications by authors named "Fei-yang Diao"

8 Publications

  • Page 1 of 1

Involvement of kisspeptin in androgen-induced hypothalamic endoplasmic reticulum stress and its rescuing effect in PCOS rats.

Biochim Biophys Acta Mol Basis Dis 2021 Aug 10;1867(12):166242. Epub 2021 Aug 10.

Epithelial Cell Biology Research Center, School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong. Electronic address:

Endoplasmic reticulum (ER) stress, with adaptive unfolded protein response (UPR), is a key link between obesity, insulin resistance and type 2 diabetes, all of which are often present in the most common endocrine-metabolic disorder in women of reproductive age, polycystic ovary syndrome (PCOS), which is characterized with hyperandrogenism. However, the link between excess androgen and endoplasmic reticulum (ER) stress/insulin resistance in patients with polycystic ovary syndrome (PCOS) is unknown. An unexpected role of kisspeptin was reported in the regulation of UPR pathways and its involvement in the androgen-induced ER stress in hypothalamic neuronal cells. To evaluate the relationship of kisspeptin and ER stress, we detected kisspeptin and other factors in blood plasm of PCOS patients, rat models and hypothalamic neuronal cells. We detected higher testosterone and lower kisspeptin levels in the plasma of PCOS than that in non-PCOS women. We established a PCOS rat model by dihydrotestosterone (DHT) chronic exposure, and observed significantly downregulated kisspeptin expression and activated UPR pathways in PCOS rat hypothalamus compared to that in controls. Inhibition or knockdown of kisspeptin completely mimicked the enhancing effect of DHT on UPR pathways in a hypothalamic neuronal cell line, GT1-7. Kp10, the most potent peptide of kisspeptin, effectively reversed or suppressed the activated UPR pathways induced by DHT or thapsigargin, an ER stress activator, in GT1-7 cells, as well as in the hypothalamus in PCOS rats. Similarly, kisspeptin attenuated thapsigargin-induced Ca response and the DHT- induced insulin resistance in GT1-7 cells. Collectively, the present study has revealed an unexpected protective role of kisspeptin against ER stress and insulin resistance in the hypothalamus and has provided a new treatment strategy targeting hypothalamic ER stress and insulin resistance with kisspeptin as a potential therapeutic agent.
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http://dx.doi.org/10.1016/j.bbadis.2021.166242DOI Listing
August 2021

Hypoxia-induced and HIF1α-VEGF-mediated tight junction dysfunction in choriocarcinoma cells: Implications for preeclampsia.

Clin Chim Acta 2019 Feb 6;489:203-211. Epub 2017 Dec 6.

State Key Laboratory of Reproductive Medicine, Center of Clinical Reproductive Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, China. Electronic address:

Introduction: Accumulated data indicate that placental hypoxia is implicated in the pathogenesis of preeclampsia (PE). Tight junction (TJ) is important structure that sustains normal placental barrier function, its dysregulation under hypoxia has been observed. This study was designed to explore hypoxia-induced TJ dysfunction in trophoblast cells and its possible involvement in PE pathophysiology.

Methods: Choriocarcinoma cells were grown in a monolayer and treated with cobalt chloride (CoCl) to induce hypoxia. TJ architecture was assessed using transmission electron microscopy, and locations of TJ proteins were determined by immunofluorescence. TJ functions were assessed by transepithelial electrical resistance (TER) and increased cell paracellular permeability (CPP), and the expression of TJ-related proteins, HIF-1α and VEGF was measured.

Results: The TJ functions of trophoblast cells were significantly altered by hypoxia; TER decreased and CPP increased in a time- and concentration-dependent manner. Significant alterations in TJ protein expression and increases in HIF1α and VEGF expression were observed in hypoxic cells, and these effects were attenuated by pretreatment with YC-1. Moreover, corresponding changes in TJ protein expression were also detected in preeclamptic placentas.

Conclusion: These data demonstrate that trophoblast cells undergo significant changes in TJ protein expression under hypoxic conditions and highlight the potential significance of the HIF1α-VEGF axis in the regulation of TJ structure and function in the preeclamptic placenta.
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http://dx.doi.org/10.1016/j.cca.2017.12.010DOI Listing
February 2019

Abnormal CFTR Affects Glucagon Production by Islet α Cells in Cystic Fibrosis and Polycystic Ovarian Syndrome.

Front Physiol 2017 17;8:835. Epub 2017 Nov 17.

Epithelial Cell Biology Research Centre, School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, Hong Kong.

Glucagon, produced by islet α cells, functions to increase blood glucose. Abnormal glucose levels are often seen in cystic fibrosis (CF), a systematic disease caused by mutations of the CF transmembrane conductance regulator (CFTR), and in polycystic ovarian syndrome (PCOS), an endocrine disorder featured with hyperandrogenism affecting 5-10% women of reproductive age. Here, we explored the role of CFTR in glucagon production in α cells and its possible contribution to glucagon disturbance in CF and PCOS. We found elevated fasting glucagon levels in CFTR mutant (DF508) mice compared to the wildtypes. Glucagon and prohormone convertase 2 (PC2) were also upregulated in CFTR inhibitor-treated or DF508 islets, as compared to the controls or wildtypes, respectively. Dihydrotestosterone (DHT)-induced PCOS rats exhibited significantly lower fasting glucagon levels with higher CFTR expression in α cells compared to that of controls. Treatment of mouse islets or αTC1-9 cells with DHT enhanced CFTR expression and reduced the levels of glucagon and PC2. The inhibitory effect of DHT on glucagon production was blocked by CFTR inhibitors in mouse islets, and mimicked by overexpressing CFTR in αTC1-9 cells with reduced phosphorylation of the cAMP/Ca response element binding protein (p-CREB), a key transcription factor for glucagon and PC2. These results revealed a previously undefined role of CFTR in suppressing glucagon production in α-cells, defects in which may contribute to glucose metabolic disorder seen in CF and PCOS.
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http://dx.doi.org/10.3389/fphys.2017.00835DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5698272PMC
November 2017

Effect of HSP10 on apoptosis induced by testosterone in cultured mouse ovarian granulosa cells.

Eur J Obstet Gynecol Reprod Biol 2013 Dec 29;171(2):301-6. Epub 2013 Sep 29.

State Key Laboratory of Reproductive Medicine, Clinical Centre of Reproductive Medicine, First Affiliated Hospital, Nanjing Medical University, Nanjing, China.

Objective: To investigate the effect of heat shock protein 10 (HSP10) on apoptosis induced by testosterone in granulosa cells (GCs) of mouse ovaries in order to define the possible roles of HSP10 in ovarian pathological development of polycystic ovarian syndrome (PCOS) and hyperandrogenic conditions.

Study Design: Cultured mouse ovarian GCs were treated with testosterone (10(-5) mol/l). Apoptosis was assessed using flow cytometry, and proliferation was assessed using the MTT assay. HSP10 expression in the treated GCs was detected by real-time polymerase chain reaction (PCR). HSP10 gene was downregulated in the cultured GCs by AdCMV-H1-SiRNA/HSP10 or overexpressed by AdCMV-HSP10. PD98059 [phosphorylated ERK (p-ERK) inhibitor] was used to treat GCs to induce a high apoptosis index. Critical apoptotic factors and proliferation factors, including P-ERK, Bcl-2, Bax, caspase 9, caspase 3 and Ki67, were monitored by real-time reverse transcriptase PCR (RT-PCR) and Western blot.

Results: Compared with the control group, the apoptosis index was higher (p<0.05) and HSP10 expression was lower (p<0.05) in the testosterone-treated groups. In the AdCMV-H1-SiRNA/HSP10-treated group, cell viability was decreased (p<0.05) and the cell cycle was arrested at G2. Expression of p-ERK, Bcl-2 and Ki67, and the Bcl-2:Bax ratio were lower, while expression of apoptotic factors, including Bax, caspase 9 and caspase 3, was higher (p<0.05). Compared with the control group, Bcl-2 expression in the GCs that overexpressed HSP10 was increased (p<0.05), while the reduction of p-ERK and Bcl-2 and the elevation of caspase 9 and caspase 3 induced by PD98059 were significantly suppressed (p<0.05).

Conclusions: Hyperandrogenic conditions induced apoptosis of mouse GCs. Testosterone may have reduced HSP10 expression in GCs, leading to reduced Bcl-2 expression and increased Bax expression.
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http://dx.doi.org/10.1016/j.ejogrb.2013.09.026DOI Listing
December 2013

[Correlation between serum progesterone level at the day with human chorionic gonadotrophin administration and the outcome of pregnancy in in-vitro fertilization].

Zhonghua Fu Chan Ke Za Zhi 2010 Feb;45(2):118-23

Department of Reproductive Medicine, First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China.

Objective: To investigate the relationship between serum progesterone level at the day with human chorionic gonadotrophin (hCG) administration and pregnant outcome from in in-vitro fertilization-embryo transfer (IVF-ET).

Methods: From Mar. 2002 to Apr. 2007, 786 cycles with serum progesterone measurement on the day of hCG administration for final oocyte maturation in IVF were analyzed retrospectively in Reproductive Medicine Center in First Affiliated Hospital of Nanjing Medical University. All stimulations were down-regulated with gronadotrophin release hormone agonist (GnRH-a) in both long protocols and short protocols before gonadotrophin stimulation. When the thresholds of serum progesterone were set at 5.5, 6.0, 6.5, 7.0, 7.5, 8.0, 8.5 and 9.0 nmol/L, respectively. If the level of progesterone was less than the thresholds, those patients were in lower progesterone group, on the contrary, more than the threshold value, those patients were in higher progesterone group. The laboratory results and the clinical outcomes between all patients at lower and higher progesterone group at different thresholds value were analyzed.

Results: The rate of normal fertilization, quality embryos, successful implantation, chemical pregnancy, clinical pregnancy and live birth did not exhibit remarkable difference between patients with higher and lower serum progesterone level at multiple thresholds on the day of hCG administration in the 786 cycles (P > 0.05). However, when the thresholds of serum progesterone were at 8.5 and 9.0 nmol/L, early abortion rates of 27.3% (3/11) and 3/7 in higher progesterone group were significantly higher than 8.8% (26/297) and 8.6% (26/301) in lower progesterone group (P < 0.05). And the total abortion rates of 3/7 in higher progesterone group were significantly higher than 11.0% (34/301) in lower progesterone group when the thresholds of serum progesterone were 9.0 nmol/L (P < 0.05).

Conclusions: This study did not prove the correlationship between progesterone level at the day with hCG administration and the probability of clinical pregnancy or live birth. However, early abortion rates or the total abortion rates were associated with higher progesterone level when the thresholds of serum progesterone were at 8.5 nmol/L or 9.0 nmol/L.
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February 2010

The orphan nuclear receptor NR4A1 regulates transcription of key steroidogenic enzymes in ovarian theca cells.

Mol Cell Endocrinol 2010 May 18;319(1-2):39-46. Epub 2010 Jan 18.

Jiangsu Province Key Laboratory of Reproductive Medicine, Nanjing Medical University, PR China.

Orphan nuclear receptor NR4A1, a member of the nuclear receptor superfamily, is widely expressed in different cell types and mediates diverse biological processes. Recent emerging evidence suggests that NR4A1 is involved in the transcriptional regulation of several steroidogenic enzyme genes in gonads and adrenals. However, its function in ovarian theca cells remains to be defined. In the present study, immunohistochemical staining of NR4A1 in healthy human ovaries indicate that it is expressed in theca cells and granulosa cells. In an effort to explore the function of NR4A1 in the transcript regulation of steroidogenic enzyme genes responsible for ovarian theca cell steroidogenesis, we constructed recombinant adenovirus AdCMV-NR4A1 and AdH1-NR4A1 to enhance or knockdown the expression of NR4A1 in theca cells, respectively. The expression patterns of StAR, CYP11A1, CYP17 and HSD3B2 were subsequently analyzed by real-time RT-PCR. Moreover, concentrations of testosterone in the spent medium were measured by radioimmunoassay. Our results show that overexpression of NR4A1 in theca cells stimulates the expression of StAR, CYP11A1, CYP17 and HSD3B2, leading to increased testosterone production. Conversely, knockdown of the endogenous NR4A1 exhibits a significant decrease in StAR, CYP11A1, CYP17 and HSD3B2 expression and testosterone production. Since expression of NR4A1 in the endocrine organs is known to be regulated by both cAMP/PKA mediated hormones, ACTH and LH, forskolin (FSK), an activator of cAMP/PKA pathway, was applied to the cultured follicles. FSK rapidly increases the NR4A1 mRNA levels followed by an increase in StAR, CYP11A1, CYP17 and HSD3B2. Collectively, our results outline a previously unrecognized role for NR4A1 in the transcriptional regulation of StAR, CYP11A1, CYP17 and HSD3B2 in ovarian theca cells. Modulation of these steroidogenic enzymes by NR4A1 could influence the capacity of the ovarian theca cells to produce androgen.
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http://dx.doi.org/10.1016/j.mce.2010.01.014DOI Listing
May 2010

The molecular characteristics of polycystic ovary syndrome (PCOS) ovary defined by human ovary cDNA microarray.

J Mol Endocrinol 2004 Aug;33(1):59-72

Department of Obstetrics and Gynecology, First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, China.

Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorders; it is characterized by polycystic ovaries, hyperandrogenism and chronic anovulation. To obtain a global view of those genes that might be involved in the development of this complex clinical disorder, we used recently developed cDNA microarray technology to compare differential gene expressions between normal human ovary and ovaries from PCOS patients. A total of 9216 clones randomly selected from a commercial human ovary cDNA library were screened. Among them, 290 clones showed differential expressions, including 119 known genes and 100 known or unknown expressed sequence tags (ESTs). Among 119 known genes, 88 were upregulated and 31 downregulated in the PCOS ovary, as compared with normal human ovary. These differentially expressed genes are involved in various biologic functions, such as cell division/apoptosis, regulation of gene expression and metabolism, reflecting the complexity of clinical manifestations of PCOS. The molecular characteristics established from our study will further our understanding of the pathogenesis of PCOS and help us to identify new targets for further studies and for the development of new therapeutic interventions.
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http://dx.doi.org/10.1677/jme.0.0330059DOI Listing
August 2004

[Analysis of X chromosome mosaicism in patients with premature ovarian failure by fluorescent in-situ hybridization].

Zhonghua Fu Chan Ke Za Zhi 2003 Jan;38(1):20-3

Department of Obstetrics and Gynecology, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China.

Objective: To investigate whether low-level 45, X/46, XX mosaicism presents in women with premature ovarian failure (POF) and the sensitivity and specificity of fluorescent in-situ hybridization (FISH) for detecting X chromosome mosaicism.

Methods: Karyotypes of peripheral lymphocyte in 18 patients with POF and 9 normal controls were analyzed and the orange signals during FISH using X chromosome enumeration probes (CEPX) were counted.

Results: Single signals of X chromosome (45, X) were found in 7.6% of the total counted cells, which was significantly greater than that in the controls, in spite of the normal 46, XX karyotypes by routine analyses in all POF patients.

Conclusions: This study indicated that some POF patients may attribute to low-level 45, X/46, XX mosaicism. FISH is more sensitive than the routine chromosome analyses in detecting low-level X chromosome monosomy.
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January 2003
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