scholarly journals Toll-Like Receptor 4 Inhibits Estradiol Secretion via NF-κB Signaling in Human Granulosa Cells

2021 ◽  
Vol 12 ◽  
Author(s):  
Hai-Yun Guan ◽  
He-Xia Xia ◽  
Xiu-Ying Chen ◽  
Lu Wang ◽  
Zhi-Jing Tang ◽  
...  

Toll-like receptor 4 (TLR4) may play a critical role in regulating follicular development. Data are scarce on the role of TLR4 in the follicle. This study investigated the effects of TLR4 on steroidogenesis in human granulosa cells. Immunohistochemical analysis revealed stage-specific expression of TLR4 in the mouse ovarian cycle, and immunofluorescence showed TLR4 expression in the human granulosa-like tumor cell line (KGN). TLR4 agonist lipopolysaccharides (LPS) significantly inhibited follicular development and synthesis of estradiol (E2) in mice. In KGN cells, TLR4 activation significantly inhibited CYP19A1, FSHR and StAR, and TLR4 inhibition reversed these effects. TLR4 activation also inhibited forskolin-induced secretion of E2 by inhibiting CYP19A1, with no effect on progesterone. Further studies showed activation of p38, JNK and NF-κB signaling after TLR4 activation. Subsequent analyses showed that an NF-κB antagonist reversed the inhibitory effects on CYP19A1 expression and E2 secretion. Together, our results suggest that TLR4 activation may suppress CYP19A1 expression and E2 secretion via NF-κB signaling in human granulosa cells, with important implications for the regulation of ovarian pathophysiology.

2020 ◽  
Vol 4 (Supplement_1) ◽  
Author(s):  
Lixian Qin ◽  
Chantacha Sitticharoon ◽  
Rungnapa Sririwichitchai ◽  
Issarawan Keadkraichaiwat ◽  
Pailin Maikaew ◽  
...  

Abstract Kisspeptin has a central role to stimulate the hypothalamic-pituitary-gonadal (HPG) axis. Furthermore, a previous study has suggested that kisspeptin might have a peripheral role in follicular development (1). This study aimed to 1) explore the effect of kisspeptin on CYP19A1 (aromatase) mRNA expression in human granulosa cells and aromatase concentrations in the supernatant; and 2) investigate the effect of kisspeptin on FSHR mRNA expression in human granulosa cells. In this study, human granulosa-like tumor cell line (KGN) (n=3) was incubated for 24 hours with FSH (10-8 M); FSH with IGF-1 (10-8 M); different doses of kisspeptin including 1, 10, 100, 1,000, and 10,000 nM; FSH with different doses of kisspeptin; and FSH with IGF-1 together with different doses of kisspeptin. FSH treatment alone or FSH with IGF-1 did not increase CYP19A1 mRNA expression when compared to control. Interestingly, kisspeptin treatment at the doses of 100 nM (P=0.028), 1,000 nM (P=0.005), and 10,000 nM (P=0.009) in the presence of FSH together with IGF-1 enhanced CYP19A1 mRNA expression when compared with control. Furthermore, FSH or FSH with IGF-1 or FSH with all doses of kisspeptin or FSH with IGF-1 together with all doses of kisspeptin increased aromatase concentrations in the supernatant when compared to control (P<0.01 all). Surprisingly, kisspeptin at the dose of 10,000 nM with FSH or FSH together with IGF-1 statistically increased aromatase concentrations in the supernatant when compared with FSH treatment alone or FSH with IGF-1 treatment (P<0.01 all). FSHR mRNA expression was comparable between control and all treatments. As a result, kisspeptin combined with FSH and IGF-1 could enhance CYP19A1 mRNA expression in human granulosa cells and the high dose of kisspeptin (10,000 nM) might be able to augment aromatase secretion in the supernatant. These results suggest that kisspeptin might enhance aromatase expression and secretion, which probably leads to enhance estrogen synthesis. Further studies regarding kisspeptin treatment on estrogen synthesis or secretion in human granulosa cells should be confirmed. Reference: (1) Fernandois D, et al. J Endocrinol. 2016;228(3):161-70.


2017 ◽  
Vol 4 (S) ◽  
pp. 117
Author(s):  
Thi Mong Diep Nguyen ◽  
Danièle Klett ◽  
Minh Thu Vo ◽  
Yves Combarnous

Fluoxetine (Prozac), a selective Serotonin Reuptake Inhibitor antidepressant, exhibits other mechanisms of action in various cell types and has been shown to induce cell death in cancer cells, paving the way for its potential use in cancer therapy. The ovary is a complex endocrine organ responsible for steroidogenesis and folliculogenesis, and human granulosa cells are essential for scientific research to improve the understanding of these two processes. However, little is known about fundamental signaling pathways in human granulosa cells. In this study, we investigated the dynamics of intracellular cyclic adenosine monophosphate AMP, a conserved signaling messenger that can regulate virtually every physiological process. We show that incubating COV434 human ovarian granulosa cells with fluoxetine induces a decrease in intracellular cAMP response to Follicle-stimulating hormone (FSH) and forskolin (FSK). In order to study the intracellular cAMP kinetic responses of COV434 cells to FSH or FSK, we used COV434 cells transiently expressing a chimeric cAMP-responsive luciferase so that real-time variations of intracellular cAMP concentration could be monitored, by using oxiluciferin luminescence produced from catalyzed luciferin oxidation. Our data show that fluoxetine induces an increase in the extracellular Ca2+ entry and reduces ATP concentration as well as cell viability. Targeting these signaling pathways with fluoxetine could permit to get better knowledge in the molecular mechanisms involved in ovarian follicular development


2019 ◽  
Vol 101 (2) ◽  
pp. 445-456 ◽  
Author(s):  
Shuang Liu ◽  
Hsun-Ming Chang ◽  
Yuyin Yi ◽  
Yuan-Qing Yao ◽  
Peter C K Leung

Abstract Connective tissue growth factor (also known as CTGF or CCN2) is a secreted matricellular protein that belongs to the CCN family. With wide-ranging biological activities and tissue expression patterns, CTGF plays a critical role in regulating various cellular functions. In the female reproductive system, CTGF is highly expressed in granulosa cells in growing ovarian follicles and is involved in the regulation of follicular development, ovulation, and luteal function. In the mammalian ovary, bone morphogenetic protein 6 (BMP6) is an important intraovarian modulator of follicular development. In this study, we demonstrated that BMP6 treatment significantly increased the expression of CTGF in both primary and immortalized human granulosa cells. Using both pharmacological inhibitors and Small interfering RNA-mediated knockdown approaches, we showed that ALK2 and ALK3 type I receptors are required for BMP6-induced cellular activities. Furthermore, this effect is most likely mediated by a Sma- and Mad-related protein (SMAD)-dependent pathway. Our studies provide novel insight into the molecular mechanisms by which an intraovarian growth factor affects the production of another factor via a paracrine effect in human granulosa cells.


Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3127
Author(s):  
Jiyeon Choi ◽  
Joo Weon Lim ◽  
Hyeyoung Kim

House dust mites (HDM) are critical factors in airway inflammation. They activate respiratory epithelial cells to produce reactive oxygen species (ROS) and activate Toll-like receptor 4 (TLR4). ROS induce the expression of inflammatory cytokines in respiratory epithelial cells. Lycopene is a potent antioxidant nutrient with anti-inflammatory activity. The present study aimed to investigate whether HDM induce intracellular and mitochondrial ROS production, TLR4 activation, and pro-inflammatory cytokine expression (IL-6 and IL-8) in respiratory epithelial A549 cells. Additionally, we examined whether lycopene inhibits HDM-induced alterations in A549 cells. The treatment of A549 cells with HDM activated TLR4, induced the expression of IL-6 and IL-8, and increased intracellular and mitochondrial ROS levels. TAK242, a TLR4 inhibitor, suppressed both HDM-induced ROS production and cytokine expression. Furthermore, lycopene inhibited the HDM-induced TLR4 activation and cytokine expression, along with reducing the intracellular and mitochondrial ROS levels in HDM-treated cells. These results collectively indicated that the HDM induced TLR4 activation and increased intracellular and mitochondrial ROS levels, thus resulting in the induction of cytokine expression in respiratory epithelial cells. The antioxidant lycopene could inhibit HDM-induced cytokine expression, possibly by suppressing TLR4 activation and reducing the intracellular and mitochondrial ROS levels in respiratory epithelial cells.


2013 ◽  
Vol 27 (12) ◽  
pp. 2093-2104 ◽  
Author(s):  
Hsun-Ming Chang ◽  
Jung-Chien Cheng ◽  
Christian Klausen ◽  
Peter C. K. Leung

In addition to somatic cell-derived growth factors, oocyte-derived growth differentiation factor (GDF)9 and bone morphogenetic protein (BMP)15 play essential roles in female fertility. However, few studies have investigated their effects on human ovarian steroidogenesis, and fewer still have examined their differential effects or underlying molecular determinants. In the present study, we used immortalized human granulosa cells (SVOG) and human granulosa cell tumor cells (KGN) to compare the effects of GDF9 and BMP15 on steroidogenic enzyme expression and investigate potential mechanisms of action. In SVOG cells, neither GDF9 nor BMP15 affects the mRNA levels of P450 side-chain cleavage enzyme or 3β-hydroxysteroid dehydrogenase. However, treatment with BMP15, but not GDF9, significantly decreases steroidogenic acute regulatory protein (StAR) mRNA and protein levels as well as progesterone production. These suppressive effects, along with the induction of Sma and Mad-related protein (SMAD)1/5/8 phosphorylation, are attenuated by cotreatment with 2 different BMP type I receptor inhibitors (dorsomorphin and DMH-1). Furthermore, depletion of activin receptor-like kinase (ALK)3 using small interfering RNA reverses the effects of BMP15 on SMAD1/5/8 phosphorylation and StAR expression. Similarly, knockdown of ALK3 abolishes BMP15-induced SMAD1/5/8 phosphorylation in KGN cells. These results provide evidence that oocyte-derived BMP15 down-regulates StAR expression and decreases progesterone production in human granulosa cells, likely via ALK3-mediated SMAD1/5/8 signaling. Our findings suggest that oocyte may play a critical role in the regulation of progesterone to prevent premature luteinization during the late stage of follicle development.


2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Monica Molteni ◽  
Sabrina Gemma ◽  
Carlo Rossetti

Toll-like receptor 4 (TLR4) belongs to the family of pattern recognition receptors (PRRs). They are highly conserved receptors that recognize conserved pathogen-associated molecular patterns (PAMPs), thus representing the first line of defense against infections. TLR4 has been long recognized as the sensing receptor for gram-negative lipopolysaccharide (LPS). In addition, it also binds endogenous molecules produced as a result of tissue injury. Hence, TLR4 represents a key receptor on which both infectious and noninfectious stimuli converge to induce a proinflammatory response. TLR4-mediated inflammation, triggered by exogenous or endogenous ligands, is also involved in several acute and chronic diseases, having a pivotal role as amplifier of the inflammatory response. This review focuses on the research progress about the role of TLR4 activation in infectious and noninfectious (e.g., sterile) inflammation and the effects of TLR4 signaling in some pathological conditions.


2019 ◽  
Vol 315 ◽  
pp. 23-30 ◽  
Author(s):  
Yun-Jie Shi ◽  
Hai-Feng Gong ◽  
Quan-Quan Zhao ◽  
Xiao-Shuang Liu ◽  
Cong Liu ◽  
...  

Endocrinology ◽  
2000 ◽  
Vol 141 (12) ◽  
pp. 4777-4783 ◽  
Author(s):  
Joy Y. Wu ◽  
Ignacio J. Gonzalez-Robayna ◽  
JoAnne S. Richards ◽  
Anthony R. Means

Abstract Ca2+/calmodulin-dependent protein kinase IV (CaMKIV) is a serine/threonine protein kinase with limited tissue distribution. CaMKIV is highly expressed in the testis, where it is found in transcriptionally inactive elongating spermatids. We have recently generated mice deficient in CaMKIV. In the absence of CaMKIV, the exchange of sperm nuclear basic proteins in male spermatids is impaired, resulting in male infertility secondary to defective spermiogenesis. The involvement of CaMKIV in female fertility has not been addressed. Here we report that female fertility is markedly reduced in CaMKIV-deficient mice due to impaired follicular development and ovulation. CaMKIV is expressed in the ovary, where it is localized in granulosa cells. We further find that in cultured granulosa cells, CaMKIV expression and subcellular localization are hormonally regulated. As granulosa cells differentiate, CaMKIV levels decrease and the kinase translocates from the nucleus into the cytoplasm. Our results demonstrate a critical role for CaMKIV in female reproduction and point to a potential function in granulosa cell differentiation.


2017 ◽  
Vol 114 (48) ◽  
pp. E10399-E10408 ◽  
Author(s):  
Jessica C. Jang ◽  
Jiang Li ◽  
Luca Gambini ◽  
Hashini M. Batugedara ◽  
Sandeep Sati ◽  
...  

Helminths trigger multiple immunomodulatory pathways that can protect from sepsis. Human resistin (hRetn) is an immune cell-derived protein that is highly elevated in helminth infection and sepsis. However, the function of hRetn in sepsis, or whether hRetn influences helminth protection against sepsis, is unknown. Employing hRetn-expressing transgenic mice (hRETNTg+) and recombinant hRetn, we identify a therapeutic function for hRetn in lipopolysaccharide (LPS)-induced septic shock. hRetn promoted helminth-induced immunomodulation, with increased survival of Nippostrongylus brasiliensis (Nb)-infected hRETNTg+ mice after a fatal LPS dose compared with naive mice or Nb-infected hRETNTg− mice. Employing immunoprecipitation assays, hRETNTg+Tlr4−/− mice, and human immune cell culture, we demonstrate that hRetn binds the LPS receptor Toll-like receptor 4 (TLR4) through its N terminal and modulates STAT3 and TBK1 signaling, triggering a switch from proinflammatory to anti-inflammatory responses. Further, we generate hRetn N-terminal peptides that are able to block LPS proinflammatory function. Together, our studies identify a critical role for hRetn in blocking LPS function with important clinical significance in helminth-induced immunomodulation and sepsis.


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