HIF-1α Activation Promotes Luteolysis by Enhancing ROS Levels in the Corpus Luteum of Pseudopregnant Rats

The increase of oxidative stress is one of the important characteristics of mammalian luteal regression. Previous investigations have revealed the essential role of reactive oxygen species (ROS) in luteal cell death during luteolysis, while it is unknown how ROS is regulated in this process. Considering the decrease of blood flow and increase of PGF2α during luteolysis, we hypothesized that the HIF-1α pathway may be involved in the regulation of ROS in the luteal cell of the late corpus luteum (CL). Here, by using a pseudopregnant rat model, we showed that the level of both HIF-1α and its downstream BNIP3 was increased during luteal regression. Consistently, we observed the increase of autophagy level during luteolysis, which is regulated in a Beclin1-independent manner. Comparing with early (Day 7 of pseudopregnancy) and middle CL (Day 14), the level of ROS was significantly increased in late CL, indicating the contribution of oxidative stress in luteolysis. Inhibition of HIF-1α by echinomycin (Ech), a potent HIF-1α inhibitor, ameliorated the upregulation of BNIP3 and NIX, as well as the induction of autophagy and the accumulation of ROS in luteal cells on Day 21 of pseudopregnancy. Morphologically, Ech treatment delayed the atrophy of the luteal structure at the late-luteal stage. An in vitro study indicated that inhibition of HIF-1α can also attenuate PGF2α-induced ROS and luteal cell apoptosis. Furthermore, the decrease of cell apoptosis can also be observed by ROS inhibition under PGF2α treatment. Taken together, our results indicated that HIF-1α signaling is involved in the regression of CL by modulating ROS production via orchestrating autophagy. Inhibition of HIF-1α could obviously hamper the apoptosis of luteal cells and the process of luteal regression.

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Deciphering the functional role of EGR1 in Prostaglandin F2 alpha induced luteal regression applying CRISPR in corpus luteum of buffalo

Biological Research ◽

10.1186/s40659-021-00333-7 ◽

2021 ◽

Vol 54 (1) ◽

Author(s):

Meeti Punetha ◽

Sai Kumar ◽

Avishek Paul ◽

Bosco Jose ◽

Jaya Bharati ◽

...

Keyword(s):

Mrna Expression ◽

Corpus Luteum ◽

Caspase 3 ◽

Cellular Proliferation ◽

Luteal Cell ◽

Wild Type ◽

Luteal Regression ◽

Luteal Cells ◽

Prostaglandin F2 Alpha

Abstract Background PGF2α is essential for the induction of the corpus luteum regression which in turn reduces progesterone production. Early growth response (EGR) proteins are Cys2-His2-type zinc-finger transcription factor that are strongly linked to cellular proliferation, survival and apoptosis. Rapid elevation of EGR1 was observed after luteolytic dose of PGF2α. EGR1 is involved in the transactivation of many genes, including TGFβ1, which plays an important role during luteal regression. Methods The current study was conducted in buffalo luteal cells with the aim to better understand the role of EGR1 in transactivation of TGFβ1 during PGF2α induced luteal regression. Luteal cells from mid stage corpus luteum of buffalo were cultured and treated with different doses of PGF2α for different time durations. Relative expression of mRNAs encoding for enzymes within the progesterone biosynthetic pathway (3βHSD, CYP11A1 and StAR); Caspase 3; AKT were analyzed to confirm the occurrence of luteolytic event. To determine if EGR1 is involved in the PGF2α induced luteal regression via induction of TGFβ1 expression, we knocked out the EGR1 gene by using CRISPR/Cas9. Result The present experiment determined whether EGR1 protein expression in luteal cells was responsive to PGF2α treatment. Quantification of EGR1 and TGFβ1 mRNA showed significant up regulation in luteal cells of buffalo at 12 h post PGF2α induction. In order to validate the role of PGF2α on stimulating the expression of TGFβ1 by an EGR1 dependent mechanism we knocked out EGR1. The EGR1 ablated luteal cells were stimulated with PGF2α and it was observed that EGR1 KO did not modulate the PGF2α induced expression of TGFβ1. In PGF2α treated EGR1 KO luteal cell, the mRNA expression of Caspase 3 was significantly increased compared to PGF2α treated wild type luteal cells maintained for 12 h. We also studied the influence of EGR1 on steroidogenesis. The EGR1 KO luteal cells with PGF2α treatment showed no substantial difference either in the progesterone concentration or in StAR mRNA expression with PGF2α-treated wild type luteal cells. Conclusion These results suggest that EGR1 signaling is not the only factor which plays a role in the regulation of PGF2α induced TGFβ1 signaling for luteolysis.

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Serum Fetuin-B Levels Are Elevated in Women with Metabolic Syndrome and Associated with Increased Oxidative Stress

Oxidative Medicine and Cellular Longevity ◽

10.1155/2021/6657658 ◽

2021 ◽

Vol 2021 ◽

pp. 1-17

Author(s):

Shiyao Xue ◽

Hongdong Han ◽

Shunli Rui ◽

Mengliu Yang ◽

Yizhou Huang ◽

...

Keyword(s):

Oxidative Stress ◽

Healthy Subjects ◽

Bioinformatics Analysis ◽

Cholesterol Metabolism ◽

In Vitro Study ◽

Multivariate Regression Analysis ◽

Regulatory Factors ◽

Triglyceride Content

Previous studies on serum fetuin-B (fetuin-like protein IRL685) have investigated its association with T2DM; however, the reason for the variation in serum fetuin-B and its regulatory factors in metabolic disease remain unclear. Here, we evaluated serum fetuin-B levels in women with newly diagnosed MetS and performed multiple interventions to investigate the role of fetuin-B in the pathogenesis of MetS. Serum fetuin-B levels were assessed using ELISA. Bioinformatics analysis was performed to analyze fetuin-B-related genes and signaling pathways. Additionally, oxidative stress parameters were measured in the in vitro study. For subgroup analyses, we performed EHC, OGTT, and treatment with a GLP-1RA to investigate the regulatory factors of serum fetuin-B. We found that in comparison with healthy subjects, serum fetuin-B levels were markedly increased in women with MetS. Further, serum fetuin-B showed a positive correlation with WHR, FAT%, TG, FBG, HbA1c, FIns, HOMA-IR, VAI, and LAP. Bioinformatics analysis revealed that most fetuin-B-related core genes were involved in cholesterol metabolism and fat decomposition. Consistent with this finding, multivariate regression analysis showed that triglyceride content and WHR were independently associated with serum fetuin-B. We also observed that serum fetuin-B levels were markedly elevated in healthy subjects after glucose loading and in women with MetS during EHC. In vitro, overexpression of fetuin-B promoted oxidative stress in HepG2 cell. After 6 months of treatment with a GLP-1RA, serum fetuin-B levels in women with MetS decreased following an improvement in metabolism and insulin sensitivity. Therefore, serum fetuin-B is associated with MetS, which may serve as a biomarker of oxidative stress. This trial is registered with ChiCTR-OCC-11001422.

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Control of Steroidogenesis in Small and Large Bovine Luteal. Cells

Australian Journal of Biological Sciences ◽

10.1071/bi9870331 ◽

1987 ◽

Vol 40 (3) ◽

pp. 331 ◽

Cited By ~ 45

Author(s):

William Hansel ◽

Hector W Alila ◽

Joseph P Dowd ◽

Xiangzhong Yang

Keyword(s):

Protein Kinase C ◽

Protein Kinase ◽

Corpus Luteum ◽

Luteal Cell ◽

Lipoxygenase Pathway ◽

Luteal Cells ◽

Kinase C ◽

Bovine Corpus Luteum ◽

Progesterone Synthesis

Evidence was cited to show that: (1) prostacyclin (PGI2) plays a luteotrophic role in the bovine corpus luteum and that products of the lipoxygenase pathway of arachidonic acid metabolism, especially 5-hydroxyeicosatetraenoic acid play luteolytic roles; (2) oxytocin of luteal cell origin plays a role in development, and possibly in regression, of the bovine corpus luteum; and (3) luteal cells arise from two sources; the characteristic small luteal cells at all stages of the o~strous cycle and pregnancy are of theca cell origin; the large cells are of granulosa cell origin early in the cycle, but a population of theca-derived large cells appears later in the cycle. Results of in vitro studies with total dispersed cells and essentially pure preparations of large and small luteal cells indicate that : (1) the recently described Ca2+ -polyphosphoinositol-protein kinase C second messenger system is involved in progesterone synthesis in the bovine corpus luteum; (2) activation of protein kinase C is stimulatory to progesterone synthesis in the small luteal cells; (3) activation of protein kinase C has no effect on progesterone synthesis in the large luteal cells; and (4) protein kinase C exerts its luteotrophic effect in total cell preparations, in part at least, by stimulating the production of prostacyclin. The protein kinase C system may cause down regulation of LH receptors in the large cells.

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In Vitro Study of Antioxidant Activity of Serum and Plasma Samples As Well As Glutathione Exposed to Various Exogenous Stress Factors

10.21203/rs.3.rs-630921/v1 ◽

2021 ◽

Author(s):

Małgorzata Olszowy-Tomczyk ◽

Łukasz Paprotny ◽

Agnieszka Celejewska ◽

Dorota Szewczak ◽

Dorota Wianowska

Keyword(s):

Oxidative Stress ◽

Antioxidant Activity ◽

Antioxidant Properties ◽

In Vitro Study ◽

Stress Factors ◽

Plasma Samples ◽

Serum Samples ◽

Exogenous Stress

Abstract The imbalance between the production of Reactive Oxygen Species (ROS) and their sequestration promotes the formation of so-called oxidative stress conditions which are considered crucial in the aging process and development of many human diseases. Glutathione plays an essential role in the antioxidative barricade against ROS. Its role in the detoxification process of xenobiotics and carcinogen is also known. However, there are no comparative studies on the antioxidant properties of both biological samples and glutathione as well as the change in these properties as a result of exposure to various stress factors. This paper fills this gap comparing the antioxidant activity of serum and plasma samples of the known glutathione content with the activity of glutathione itself assessed by the different methods. In addition, it reveals a significant role of environmental xenobiotics in oxidative stress and differentiates the stress induced by different groups of drugs, among which the greatest one has been demonstrated for antiarrhythmic drugs and cytostatics. More importantly, it proves that human plasma is more resistant to stress factors and N-acetylcysteine clearly promotes the extension of antioxidant properties of both the plasma and serum samples. The latter conclusion is consistent with the implied preventive and/or supportive action of this drug against SARS-CoV-2.

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Does prostacyclin (PGI2) support porcine corpus luteum function? – data from in vitro study

Problems of Endocrinology ◽

10.14341/probl201662549 ◽

2016 ◽

Vol 62 (5) ◽

pp. 49

Author(s):

Magdalena Julia Szymańska ◽

Agnieszka Blitek

Keyword(s):

Endothelial Cells ◽

Mrna Expression ◽

Corpus Luteum ◽

Estrous Cycle ◽

In Vitro Study ◽

Luteal Cells ◽

Enzymatic Isolation ◽

Effective Doses ◽

And Function

Background. Prostacyclin (PGI2) of luteal origin is involved in the control of corpus luteum (CL) development and function in cattle. PGI2 may regulate the process of angiogenesis and may stimulate progesterone (P4) secretion by luteal cells via its specific receptors, PTGIR. In contrast to cattle, the role of PGI2 in the pig CL has not yet been described.Aim. The present study aimed to investigate the effect of PGI2 on 1) P4 secretion by luteal cells, and 2) the expression of angiogenesis-related genes in endothelial cells of the porcine CL.Methods. CL collected from gilts on day 5-7 of the estrous cycle were used for enzymatic isolation of luteal (Experiment 1) and endothelial (Experiment 2) cells. In Exp. 1, cultured luteal cells were incubated with increasing (0, 0.01, 0.1, 1, 5 µM) doses of PGI2 analogues: iloprost (ILO) and carbaprostacyclin (cPGI2) for 8 h. To determine the effective doses of PGI2 analogues, P4 concentration in culture medium was examined by RIA. Thereafter, luteal cells were treated with ILO and cPGI2 at the concentration of 1 and 5 µM in the presence or absence of PTGIR antagonist (CAY10441). After 8 h of incubation the medium was collected for P4 determination. In Exp. 2, isolated endothelial cells were treated for 24 h with ILO and cPGI2 at doses of 1 and 5 µM. Then, cells were collected for analysis of Ang-1 and -2 mRNA expression using qPCR.Results. Both, ILO and cPGI2 affected P4 secretion by luteal cells. Elevated levels of P4 were observed in medium after treatment of luteal cells with 1 µM of ILO and 0.1, 1 and 5 µM of cPGI2 compared with control values (p<0.05). The addition of CAY10441 inhibited the stimulatory effect of ILO on P4 secretion, while did not change P4 production by luteal cells incubated with cPGI2. Moreover, PGI2 analogues differentially affected (p<0.05) the expression of proangiogenic factors. ILO stimulated Ang-2, whereas cPGI2 positively affected Ang-1 mRNA expression in endothelial cells at concentrations of 1 µM and 5 µM, respectively.Conclusion. PGI2 affects P4 secretion during luteal phase of the estrous cycle and may regulate the process of angiogenesis in the porcine CL.

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Cell death induced by serum deprivation in luteal cells involves the intrinsic pathway of apoptosis

Reproduction ◽

10.1530/rep.1.00751 ◽

2006 ◽

Vol 131 (1) ◽

pp. 103-111 ◽

Cited By ~ 30

Author(s):

Alicia A Goyeneche ◽

Jacquelyn M Harmon ◽

Carlos M Telleria

Keyword(s):

Cell Death ◽

Corpus Luteum ◽

Simian Virus 40 ◽

Full Length ◽

Luteal Cell ◽

Serum Starvation ◽

Endocrine Gland ◽

Luteal Cells ◽

Defined Culture

The corpus luteum is a transient endocrine gland specializing in the production of progesterone. The regression of the corpus luteum involves an abrupt decline in its capacity for producing progesterone followed by its structural involution, which is associated with apoptosis of the luteal cells. An in vitro experimental approach is needed to study the molecular mechanisms underlying hormonal regulation of luteal cell death under defined experimental conditions. In this study, we investigated simian virus-40-transformed luteal cells to determine whether they can be driven to apoptosis and, if so, to define the intracellular pathway involved. Luteal cells were cultured in the presence or absence of fetal bovine serum for 24 or 48 h. Under serum starvation conditions, the luteal cells underwent growth arrest accompanied by cell death as evaluated by dye exclusion, and confirmed by two-color fluorescence cell viability/cytotoxicity assay. We next studied whether serum starvation-induced death of luteal cells occurred by apoptosis. Morphologic features of apoptosis were observed in cells stained with hematoxylin after being subjected to serum starvation for 48 h. The apoptotic nature was further confirmed by in situ 3′-end labeling and fragmentation of genomic DNA. Apoptosis of serum-deprived luteal cells was dependent upon caspase activation. Serum starvation induced cleavage of poly (ADP-ribose) polymerase (PARP), suggesting that caspase-3 had been activated under the stress of withdrawal of growth factors. This was confirmed by cleavage of full-length procaspase-3. Finally, the fact that serum starvation promoted the cleavage of full-length procaspase-9 and the decrease in the expression of endogenous Bid, a BH-3-only proapoptotic protein of the Bcl-2 family, indicates that the intrinsic (i.e., mitochondrial) pathway of apoptosis was activated. In summary, we have characterized an in vitro experimental model of luteal cell death that can be utilized to evaluate the role of hormones in apoptosis of luteal cells under defined culture conditions, and to study the mechanism of luteal regression.

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Role of phosphoprotein phosphatases in the corpus luteum: I Identification and characterisation of serine/threonine phosphoprotein phosphatases in isolated rat luteal cells

Journal of Endocrinology ◽

10.1677/joe.0.1500205 ◽

1996 ◽

Vol 150 (2) ◽

pp. 205-211 ◽

Cited By ~ 9

Author(s):

S L Ford ◽

D R E Abayasekara ◽

S J Persaud ◽

P M Jones

Keyword(s):

Polyclonal Antibodies ◽

Luteal Cell ◽

Luteal Cells ◽

Cell Functions ◽

Phosphoprotein Phosphatases ◽

Sds Page ◽

Molecular Masses ◽

Dose Dependent Decrease

Abstract Although the role of protein kinases and phosphorylation in steroidogenesis has received much attention, very little is known about the activities of phosphoprotein phosphatases (PP) and dephosphorylation in steroidogenic tissues. The aims of the present study were therefore to identify which of those serine/threonine PPs more commonly involved in intracellular signalling are expressed in rat luteal cells; to quantify, in vitro, the effects of inhibitors on PP activity extracted from purified rat luteal cells; and to measure the effects of PP inhibitors on the phosphorylation of endogenous luteal cell proteins. Polyclonal antibodies raised against the catalytic subunits of PP types 1 and 2A, and a monoclonal antibody raised against the Ca2+-binding subunit of PP2B, were used to identify immunoreactive proteins that migrated on SDS-PAGE with approximate molecular masses of 37, 34 and 16 kDa, corresponding well with the reported molecular mass of PP1, PP2A and PP2B respectively. Five selective inhibitors of PP1/PP2A: okadaic acid, calyculin A, cantharidin, tautomycin and microcystin-RR, each caused a dose-dependent decrease in the activity of PPs in luteal cell homogenates, and also enhanced 32P incorporation into numerous luteal cell proteins; most notably, proteins with approximate molecular masses of 20 and 22 kDa. The results of this study suggest that PPs may play an important role in the regulation of rat luteal cell functions. Journal of Endocrinology (1996) 150, 205–211

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Expression and regulation of secreted phosphoprotein 1 in the bovine corpus luteum and effects on T lymphocyte chemotaxis

Reproduction ◽

10.1530/rep-13-0190 ◽

2013 ◽

Vol 146 (6) ◽

pp. 527-537 ◽

Cited By ~ 7

Author(s):

Daniel H Poole ◽

Kalidou Ndiaye ◽

Joy L Pate

Keyword(s):

Corpus Luteum ◽

Estrous Cycle ◽

Cell Function ◽

Luteal Cell ◽

Cellular Interactions ◽

Western Blots ◽

Luteal Regression ◽

Luteal Cells ◽

Bovine Corpus Luteum ◽

Secreted Phosphoprotein 1

Secreted phosphoprotein 1 (SPP1) in the bovine corpus luteum (CL) regulates cell function during the transitional periods of luteinization and luteal regression. The objectives were to i) characterize SPP1 expression in the CL throughout the estrous cycle, ii) determine factors that regulate SPP1 expression in luteal cells, and iii) examine the role of SPP1 in lymphocyte chemotaxis, proliferation, and function.SPP1mRNA was greater in fully functional (d10) CL and late cycle (d18) CL compared with developing (d4) CL. Additionally,SPP1mRNA increased within 1 h and remained elevated 4 and 8 h following induction of luteolysis with prostaglandin (PG)F2α. Expression of the SPP1 receptor, β3integrin, was not different throughout the estrous cycle but decreased following induction of luteolysis. Expression ofCD44increased during the estrous cycle but did not change during luteal regression. In cultured luteal cells,SPP1mRNA was upregulated by PGF2αand/or tumor necrosis factor α. Western blots revealed the presence of both full-length SPP1 and multiple cleavage products in cultured luteal cells and luteal tissue. Depletion of endogenous SPP1 did not hinder luteal cell-induced lymphocyte proliferation or lymphocyte phenotype but did inhibit lymphocyte migration toward luteal cells. Based on these data, it is concluded that SPP1 is initially activated to establish and maintain cellular interactions between steroidogenic and nonsteroidogenic cells during the development of the CL. Upon induction of luteolysis, SPP1 serves as a signaling molecule to recruit or activate immune cells to facilitate luteal regression and tissue degradation.

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The antioxidant effects of melatonin in blood platelets during exposure to electromagnetic radiation – an in vitro study

Postępy Higieny i Medycyny Doświadczalnej ◽

10.2478/ahem-2021-0026 ◽

2021 ◽

Vol 75 (1) ◽

pp. 889-895

Author(s):

Małgorzata Lewicka ◽

Magdalena Zawadzka ◽

Gabriela Henrykowska ◽

Maciej Rutkowski ◽

Andrzej Buczyński

Keyword(s):

Oxidative Stress ◽

Electromagnetic Radiation ◽

Blood Platelets ◽

In Vitro Study ◽

Oxygen Metabolism ◽

Protective Role ◽

Negative Effect ◽

Antioxidant Effects

Abstract Objectives The article presents the results of an in vitro study aimed at identifying changes in parameters of oxidative stress – concentration of malondialdehyde (MDA), enzymatic activity of superoxide dismutase (SOD-1) and protective antioxidant role of melatonin (MLT) during the exposure of blood platelets to electromagnetic radiation (EMR) emitted by monitors. Methods Platelets were exposed to an EMR for 30- and 60 min. generated by monitors (1 kHz frequency, 220 V/m intensity). In each sample the level of SOD-1 activity and concentration of MDA were determined. Results The MDA concentration increased significantly after 30-and 60-min. irradiation, as compared to control values (2.53 vs 1.36; 3.64 vs 1.36 nmol/109 blood platelets) and after the addition of MLT it decreased (2.53 vs 1.55; 3.64 vs 1.12 nmol/109 blood platelets). The activity of SOD-1 increased significantly compared to control values after 30 min. and 60 min. of exposure to EMR (1.97vs 0.75; 2.08 vs 0.75 U/g of protein), and significantly decreased after the addition of MLT only in samples exposed for 60 min. (2.08 vs 0.95 U/g of protein). Discussion The results demonstrated the possibly negative effect of EMR on oxygen metabolism of blood platelets and indicated a possible protective role of melatonin in this process.

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VARYING RESPONSE TO LUTEINIZING HORMONE OF TWO LUTEAL CELL TYPES ISOLATED FROM BOVINE CORPUS LUTEUM

Journal of Endocrinology ◽

10.1677/joe.0.0830303 ◽

1979 ◽

Vol 83 (3) ◽

pp. 303-NP ◽

Cited By ~ 66

Author(s):

JOCELYNE URSELY ◽

PIERRE LEYMARIE

Keyword(s):

Corpus Luteum ◽

In Vitro Study ◽

Average Diameter ◽

Cell Types ◽

Enzymatic Digestion ◽

Cell Suspensions ◽

Small Cells ◽

Luteal Cell

Luteal cell suspensions obtained by enzymatic digestion of pregnant cow corpus luteum were found to be heterogenous and mainly made up of two types of cells of different sizes. The large cells (37 μm, average diameter) could be separated from the small ones (18 μm, average diameter) by sedimentation at unit gravity in a gradient of Ficoll–bovine serum albumin. A comparative in-vitro study of the synthesis of progesterone by the two types of cells indicated striking differences between them. The average content and the synthesis of progesterone in the absence and presence of a saturating dose of bovine LH after incubation for 2 h were 0·07, 0·12 and 6·9 pg/cell for the small cells and 0·65, 2 and 10 pg/cell for the large ones. Moreover, the sensitivity to low concentrations of LH was 100 to 1000 times higher for the small cells than for the large ones. oestradiol-17β at concentrations ranging from 5 × 10−10 to 5 × 10−4 mol/l exerted a dose–dependent inhibition on the stimulation of LH in both cell types. These results suggest a possible involvement of both cell types in the synthesis of progesterone in vivo with a greater contribution by the small cells to stimulation induced by LH. Moreover, it appears that small cell suspensions could be a useful model system for in-vitro studies of the control of the synthesis of progesterone in cow corpus luteum.

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