scholarly journals miR-106a Increases Granulosa Cell Viability and Is Downregulated in Women With Diminished Ovarian Reserve

2018 ◽  
Vol 103 (6) ◽  
pp. 2157-2166 ◽  
Author(s):  
Liming Hong ◽  
Sha Peng ◽  
Ying Li ◽  
Ying Fang ◽  
Qin Wang ◽  
...  

Abstract Context Women with diminished ovarian reserve (DOR) have reduced fertility, cardiovascular events, and osteoporosis. Although differential microRNA (miRNA) expression has been described in several ovarian disorders, little is known about the role of miRNAs in the pathogenesis of DOR. Objective Identify differentially expressed miRNAs in DOR and explore the role of miR-106a in human granulosa cell proliferation. Design miRNA microarray (n = 3) and quantitative reverse transcription polymerase chain reaction (n = 30) were used to examine miRNA expression in serum and granulosa cells from normal-cycling and women with DOR. Primary human granulosa cells were treated alone or in combination with miR-106a mimic, miR-106a inhibitor, apoptosis signal-regulating kinase 1 (ASK1) small interfering RNA (siRNA), or p38 mitogen-activated protein kinase (MAPK) inhibitor (SB203580) before assessment of cell viability and apoptosis. Western blot was used to measure ASK1 protein and phosphorylation/activation of p38 MAPK. Binding of miR-106a to ASK1 mRNA was examined by 3′ untranslated region (3′UTR) luciferase analysis. Results Fifteen miRNAs were differentially expressed (n = 30), and miR-106a was downregulated in serum and granulosa cells of women with DOR. miR-106a mimic increased cell viability and attenuated apoptosis, whereas the converse occurred following treatment with miR-106a inhibitor. miR-106a suppressed ASK1 expression by directly targeting its 3′UTR. miR-106a inhibitor increased p38 MAPK phosphorylation/activation, and this effect was abolished by treatment with ASK1 siRNA. Whereas knockdown of ASK1 abolished the effects of miR-106a inhibitor on cell viability/apoptosis, pretreatment with SB203580 did not significantly alter the effects of miR-106a inhibitor. Conclusions Downregulation of miR-106a may contribute to the pathogenesis of DOR by reducing granulosa cell viability and promoting apoptosis via enhanced ASK1 signaling.

2021 ◽  
Vol 22 (4) ◽  
pp. 2047
Author(s):  
Nina Schmid ◽  
Kim-Gwendolyn Dietrich ◽  
Ignasi Forne ◽  
Alexander Burges ◽  
Magdalena Szymanska ◽  
...  

Sirtuins (SIRTs) are NAD+-dependent deacetylases that regulate proliferation and cell death. In the human ovary, granulosa cells express sirtuin 1 (SIRT1), which has also been detected in human tumors derived from granulosa cells, i.e., granulosa cell tumors (GCTs), and in KGN cells. KGN cells are an established cellular model for the majority of GCTs and were used to explore the role of SIRT1. The SIRT1 activator SRT2104 increased cell proliferation. By contrast, the inhibitor EX527 reduced cell numbers, without inducing apoptosis. These results were supported by the outcome of siRNA-mediated silencing studies. A tissue microarray containing 92 GCTs revealed nuclear and/or cytoplasmic SIRT1 staining in the majority of the samples, and also, SIRT2-7 were detected in most samples. The expression of SIRT1–7 was not correlated with the survival of the patients; however, SIRT3 and SIRT7 expression was significantly correlated with the proliferation marker Ki-67, implying roles in tumor cell proliferation. SIRT3 was identified by a proteomic analysis as the most abundant SIRT in KGN. The results of the siRNA-silencing experiments indicate involvement of SIRT3 in proliferation. Thus, several SIRTs are expressed by GCTs, and SIRT1 and SIRT3 are involved in the growth regulation of KGN. If transferable to GCTs, these SIRTs may represent novel drug targets.


Reproduction ◽  
2010 ◽  
Vol 140 (2) ◽  
pp. 295-303 ◽  
Author(s):  
Jennifer L Juengel ◽  
Lisa J Haydon ◽  
Brigitta Mester ◽  
Brian P Thomson ◽  
Michael Beaumont ◽  
...  

IGFs are known to be key regulators of ovarian follicular growth in eutherian mammals, but little is known regarding their role in marsupials. To better understand the potential role of IGFs in the regulation of follicular growth in marsupials, expression of mRNAs encoding IGF1, IGF2, IGF1R, IGF-binding protein 2 (IGFBP2), IGFBP4 and IGFBP5 was localized by in situ hybridization in developing ovarian follicles of the brushtail possum. In addition, the effects of IGF1 and IGF2 on granulosa cell function were tested in vitro. Both granulosa and theca cells synthesize IGF mRNAs, with the theca expressing IGF1 mRNA and granulosa cell expressing IGF2 mRNA. Oocytes and granulosa cells express IGF1R. Granulosa and theca cells expressed IGFBP mRNAs, although the pattern of expression differed between the BPs. IGFBP5 mRNA was differentially expressed as the follicles developed with granulosa cells of antral follicles no longer expressing IGFBP5 mRNA, suggesting an increased IGF bioavailability in the antral follicle. The IGFBP protease, PAPPA mRNA, was also expressed in granulosa cells of growing follicles. Both IGF1 and IGF2 stimulated thymidine incorporation but had no effect on progesterone production. Thus, IGF may be an important regulator of ovarian follicular development in marsupials as has been shown in eutherian mammals.


2004 ◽  
Vol 92 (12) ◽  
pp. 1387-1393 ◽  
Author(s):  
Athan Kuliopulos ◽  
Ramon Mohanlal ◽  
Lidija Covic

SummarySystemic inflammation has been shown to be a contributing factor to the instability of atherosclerotic plaques in patients with acute coronary syndromes (ACS). VX-702, a novel p38 mitogen-activated protein kinase (MAPK) inhibitor, is currently under investigation in ACS patients with unstable angina to evaluate its safety and efficacy during percutaneous coronary intervention (PCI).The role of p38 MAPK in platelet aggregation of normal individuals was examined using the selective second generation p38 MAPK inhibitor VX-702. Treatment of platelets with thrombin (activates PAR1 and PAR4 thrombin receptors), SFLLRN (PAR1), AYPGKF (PAR4), collagen (α2β1 and GPVI/FCγIIR receptors) and U46619 (TXA2) resulted in strong activation of p38 MAPK. Activation of the GPIb von Willebrand factor receptor with ristocetin did not stimulate p38 MAPK. Pre-treatment of platelets with 1 μM VX-702 completely inhibited activation of p38 MAPK by thrombin, SFLLRN, AYPGKF, U46619, and collagen. There was no effect of VX-702 on platelet aggregation induced by any of the agonists in the presence or absence of aspirin, heparin or apyrase. It has been postulated that a potential role of p38 MAPK is to activate phospholipase A2 (cPLA2) which catalyses formation of arachidonic acid leading to production of thromboxane. Interestingly, we show contrasting effects of p38 MAPK inhibition as compared to aspirin inhibition on platelet aggregation in response to collagen. Blockade of TXA2 production by aspirin results in significant inhibition of collagen activation. However, VX-702 has no effect on collagen-mediated platelet aggregation, suggesting that blocking p38 MAPK does not effect thromboxane production in human platelets. Therefore, unlike aspirin blockade of thromboxane production in platelets, p38 MAPK inhibitors such as VX-702 do not significantly affect platelet function and would not be expected to contribute to an elevated risk of bleeding side-effects in treated patients.


2012 ◽  
Vol 2012 ◽  
pp. 1-12 ◽  
Author(s):  
Sônia A. L. Corrêa ◽  
Katherine L. Eales

A significant amount of evidence suggests that the p38-mitogen-activated protein kinase (MAPK) signalling cascade plays a crucial role in synaptic plasticity and in neurodegenerative diseases. In this review we will discuss the cellular localisation and activation of p38 MAPK and the recent advances on the molecular and cellular mechanisms of its substrates: MAPKAPK 2 (MK2) and tau protein. In particular we will focus our attention on the understanding of the p38 MAPK-MK2 and p38 MAPK-tau activation axis in controlling neuroinflammation, actin remodelling and tau hyperphosphorylation, processes that are thought to be involved in normal ageing as well as in neurodegenerative diseases. We will also give some insight into how elucidating the precise role of p38 MAPK-MK2 and p38 MAPK-tau signalling cascades may help to identify novel therapeutic targets to slow down the symptoms observed in neurodegenerative diseases such as Alzheimer's and Parkinson's disease.


2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
D Aydos ◽  
O S Aydos ◽  
Y Yukselten ◽  
A Sunguroglu ◽  
K Aydos

Abstract Study question Could Nrf2 polymorphism (-617C>A; rs6721961) and oxidative stress (OS)-induced changes of signature seminal plasma (SP) miRNAs related to Nrf2 provide possible biomarkers of male infertility? Summary answer -617C>A SNP is associated with infertility through sperm OS DNA damage and miR-582-5p and miR-20a-5p, differentially represented between spermatozoa of smokers-non-smokers, might regulate Nrf2/ARE axis. What is known already As an extrinsic factor causing OS, smoking decreases male infertility by causing sperm membrane damage and DNA fragmentation. Expression of proteins related to the antioxidant defense system and phase 2 detoxifying enzymes controlled mainly by Nrf2/ARE pathway components is vital in managing OS-induced DNA damage. miRNAs, which multiple of are produced abundantly in male germ cells throughout spermatogenesis, have been detected in SP and contribute to multiple biological processes related to male reproductive events. miRNA-expression alterations may be induced in response to OS and without involving DNA sequence changes, miRNAs can provide additional mechanism of regulating the Nrf2 gene expression. Study design, size, duration Wild-type (WT) and SNP (-617) alleles in the Nrf2 gene were studied in 100 infertile cases and 100 controls and their associations with seminal parameters in relation to smoking status were assessed. In infertile cases, sperm DNA damage level was determined and compared among Nrf2 genotypes. Interactions between differentially expressed miRNAs (DEMIs) in response to smoking and Nrf2/ARE pathway components were visualized on a miRNA-mRNA regulatory network using CluePedia (v1.5.7) plugin of Cytoscape software (v3.8.2). Participants/materials, setting, methods Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was utilized to genotype the Nrf2 SNP (-617). DNA damages were analyzed by Comet assay. DEMIs were identified by a comprehensive bioinformatics analysis using the miRNA expression dataset GSE44134 downloaded from the GEO database. Predicted targets of DEMIs in smokers were identified by mirDIP portal. Known interactions between Nrf2 and its first neighbors were visualized after selecting STRING-actions, miRTarBase and miRecords validated miRNA source files from CluePedia panel. Main results and the role of chance There was significant difference for Nrf2 polymorphism between fertile and infertile males. The A allele was detected more frequently in the patient group; (P = 0.001). The frequencies of the C and A alleles of the Nrf2 were 62% and 38% in patients, and 78% and 44% in control group. The AA genotype was higher in the infertiles; 14% vs. 3% (P = 0.001). In smokers, sperm quality decreased significantly in AA genotype. The risk of DNA damage was highest with 224.58 AU in the AA genotype group, whereas it is the lowest with 164.56 AU in those carrying the CC genotype (P < 0.005). 21 differentially expressed miRNAs (including 7 downregulated and 14 upregulated in smokers) were identified. Among the upregulated DEMIs, miR-582-5p, miR-20a-5p, miR-573, miR-186-5p, miR-499a-5p were found to target the Nrf2 mRNA, suggesting their usage as biomarkers capable of indicating the antioxidant ability of the male reproductive system. The interrelations between Nrf2/Nrf2 direct interactors and DEMIs revealed the regulatory role of hsa-miR-20a-5p in SQSTM1/p62-Keap1-Nrf2 axis linked to selective autophagy. hsa-miR-582-5p was found to regulate the JNK/Jun/caspase-3 pathway, previously shown to be activated in response to OS, in which JUN can activate or suppress the Nrf2 expression. Limitations, reasons for caution Small number of cases while evaluating the effect of smoking weakens our ability to generalize the results. Including other coexisting factors and larger patient groups carrying other functional variants of Nrf2 as well as confirming the results at the protein level would further strengthen the results of the study. Wider implications of the findings This study is the first to report -617C>A polymorphism in the Nrf2 gene in the Turkish population and such a SNP may cause impaired fertility in men, especially in smokers, through oxidative metabolism. Considering these data may be valuable in determining risk groups. Trial registration number N/A


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Sai Kumar ◽  
Meeti Punetha ◽  
Bosco Jose ◽  
Jaya Bharati ◽  
Shivani Khanna ◽  
...  

AbstractBMPs are multifunctional growth factors implicated in regulating the ovarian function as key intra-ovarian factors. Biological effects of BMPs are mediated through binding with membrane bound receptors like BMPR-IB and initiating downstream Smad signaling pathway. FecB mutation, regarded as a loss of function mutation in the BMPR-IB gene was identified in certain sheep breeds having high fecundity. Similar type of fecundity genes in goats have not been discovered so far. Hence, the current study was designed to investigate the effects of BMPR-IB gene modulation on granulosa cell function in goats. The BMPR-IB gene was knocked out using CRISPR-Cas technology in granulosa cells and cultured in vitro with BMP-4 stimulation for three different durations In addition, the FecB mutation was introduced in the BMPR-IB gene applying Easi-CRISPR followed by BMP-4/7 stimulation for 72 h. Steroidogenesis and cell viability were studied to explore the granulosa cell function on BMPR-IB gene modulation. BMPRs were found to be expressed stage specifically in granulosa cells of goats. Higher transcriptional abundance of R-Smads, LHR and FSHR indicating sensitisation of Smad signaling and increased gonadotropin sensitivity along with a significant reduction in the cell proliferation and viability was observed in granulosa cells upon BMPR-IB modulation. The inhibitory action of BMP-4/7 on P4 secretion was abolished in both KO and KI cells. Altogether, the study has revealed an altered Smad signaling, steroidogenesis and cell viability upon modulation of BMPR-IB gene in granulosa cells similar to that are documented in sheep breeds carrying the FecB mutation.


2009 ◽  
Vol 296 (2) ◽  
pp. C273-C284 ◽  
Author(s):  
Tsung-Chuan Ho ◽  
Show-Li Chen ◽  
Yuh-Cheng Yang ◽  
Tzu-Hsiu Lo ◽  
Jui-Wen Hsieh ◽  
...  

Pigment epithelium-derived factor (PEDF) is an intrinsic antiangiogenic factor and a potential therapeutic agent. Previously, we discovered the mechanism of PEDF-induced apoptosis of human umbilical vein endothelial cells (HUVECs) as sequential induction/activation of p38 mitogen-activated protein kinase (MAPK), peroxisome proliferator-activated receptor gamma (PPAR-γ), and p53. In the present study, we investigated the signaling role of cytosolic calcium-dependent phospholipase A2-α (cPLA2-α) to bridge p38 MAPK and PPAR-γ activation. PEDF induced cPLA2-α activation in HUVECs and in endothelial cells in chemical burn-induced vessels on mouse cornea. The cPLA2-α activation is evident from the phosphorylation and nuclear translocation of cPLA2-α as well as arachidonic acid release and the cleavage of PED6, a synthetic PLA2 substrate. Such activation can be abolished by p38 MAPK inhibitor. The PEDF-induced PPAR-γ activation, p53 expression, caspase-3 activity, and apoptosis can be abolished by both cPLA2 inhibitor and small interfering RNA targeting cPLA2-α. Our observation not only establishes the signaling role of cPLA2-α but also for the first time demonstrates the sequential activation of p38 MAPK, cPLA2-α, PPAR-γ, and p53 as the mechanism of PEDF-induced endothelial cell apoptosis.


2011 ◽  
Vol 301 (3) ◽  
pp. F509-F519 ◽  
Author(s):  
Ruma Pengal ◽  
Adam J. Guess ◽  
Shipra Agrawal ◽  
Joshua Manley ◽  
Richard F. Ransom ◽  
...  

While mitogen-activated protein kinase (MAPK) activation has been implicated in the pathogenesis of various glomerular diseases, including nephrotic syndrome (NS), its specific role in podocyte injury is not known. We hypothesized that MK-2, a downstream substrate of p38 MAPK, mediates the adverse effects of this pathway and that inhibition of MK-2 would protect podocytes from NS-related injury. Using cultured podocytes, we analyzed 1) the roles of MK-2 and p38 MAPK in puromycin aminonucleoside (PAN)-induced podocyte injury; 2) the ability of specific MK-2 and p38 MAPK inhibitors to protect podocytes against injury; 3) the role of serum albumin, known to induce podocyte injury, in activating p38 MAPK/MK-2 signaling; and 4) the role of p38 MAPK/MK-2 signaling in the expression of Cox-2, an enzyme associated with podocyte injury. Treatment with protein kinase inhibitors specific for both MK-2 (C23, a pyrrolopyridine-type compound) or p38 MAPK (SB203580) reduced PAN-induced podocyte injury and actin cytoskeletal disruption. Both inhibitors reduced baseline podocyte p38 MAPK/MK-2 signaling, as measured by the degree of phosphorylation of HSPB1, a downstream substrate of MK-2, but exhibited disparate effects on upstream signaling. Serum albumin activated p38 MAPK/MK-2 signaling and induced Cox-2 expression, and these responses were blocked by both inhibitors. Given the critical importance of podocyte injury to both NS and other progressive glomerular diseases, these data suggest an important role for p38 MAPK/MK-2 signaling in podocyte injury and identify MK-2 inhibition as a promising potential therapeutic strategy to protect podocytes in various glomerular diseases.


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