scholarly journals Prolactin Exerts a Prosurvival Effect on Human Spermatozoa via Mechanisms that Involve the Stimulation of Akt Phosphorylation and Suppression of Caspase Activation and Capacitation

Endocrinology ◽  
2009 ◽  
Vol 151 (3) ◽  
pp. 1269-1279 ◽  
Author(s):  
Dwi Ari Pujianto ◽  
Benjamin J. Curry ◽  
R. John Aitken
Keyword(s):  
Western Blot ◽  
Human Spermatozoa ◽  
Pcr Analysis ◽  
Dependent Manner ◽  
Sperm Capacitation ◽  
Caspase Activation ◽  
Apoptotic Pathway ◽  
Akt Phosphorylation ◽  
The Impact ◽  
Stimulation Of

The purpose of this study was to examine the impact of prolactin (PRL) on human sperm function, in light of a recent proteomic analysis indicating that these cells express the PRL receptor (PRLR). Immunocytochemical analyses confirmed the presence of PRLR in human spermatozoa and localized this receptor to the postacrosomal region of the sperm head as well as the neck, midpiece, and principal piece of the sperm tail. Nested PCR analysis indicated that these cells possess four splice variants of the PRLR: the long form and three short isoforms, one of which is reported for the first time. A combination of Western blot analyses and immunocytochemistry demonstrated that PRL inhibited sperm capacitation in a dose-dependent manner, suppressing SRC kinase activation and phosphotyrosine expression, two hallmarks of this process. The suppression of sperm capacitation was accompanied by a powerful prosurvival effect, supporting the prolonged motility of these cells and preventing the formation of spontaneous DNA strand breaks via mechanisms that involved the concomitant suppression of caspase activation. Western blot analyses indicated that the prosurvival effect of PRL on human spermatozoa involved the stimulation of Akt phosphorylation, whereas inhibitors of phosphatidylinositol-3-OH kinase and Akt negated this effect, as did the direct induction of sperm capacitation with cAMP analogues. We conclude that PRL is a prosurvival factor for human spermatozoa that prevents these cells from defaulting to an intrinsic apoptotic pathway associated with cell senescence. These findings have implications for preservation of sperm integrity in vivo and in vitro.

VDAC1 Mediated Anticancer Activity of Gallic Acid in Human Lung Adenocarcinoma A549 Cells

2018 ◽  
Vol 18 (2) ◽  
pp. 255-262 ◽  
Author(s):  
Aikebaier Maimaiti ◽  
Amier Aili ◽  
Hureshitanmu Kuerban ◽  
Xuejun Li
Keyword(s):  
Western Blot ◽  
Cell Viability ◽  
Gallic Acid ◽  
Molecular Mechanisms ◽  
A549 Cells ◽  
Dependent Manner ◽  
Lung Carcinoma Cells ◽  
Induced Apoptosis ◽  
The Impact

Aims: Gallic acid (GA) is generally distributed in a variety of plants and foods, and possesses cell growth-inhibiting activities in cancer cell lines. In the present study, the impact of GA on cell viability, apoptosis induction and possible molecular mechanisms in cultured A549 lung carcinoma cells was investigated. Methods: In vitro experiments showed that treating A549 cells with various concentrations of GA inhibited cell viability and induced apoptosis in a dose-dependent manner. In order to understand the mechanism by which GA inhibits cell viability, comparative proteomic analysis was applied. The changed proteins were identified by Western blot and siRNA methods. Results: Two-dimensional electrophoresis revealed changes that occurred to the cells when treated with or without GA. Four up-regulated protein spots were clearly identified as malate dehydrogenase (MDH), voltagedependent, anion-selective channel protein 1(VDAC1), calreticulin (CRT) and brain acid soluble protein 1(BASP1). VDAC1 in A549 cells was reconfirmed by western blot. Transfection with VDAC1 siRNA significantly increased cell viability after the treatment of GA. Further investigation showed that GA down regulated PI3K/Akt signaling pathways. These data strongly suggest that up-regulation of VDAC1 by GA may play an important role in GA-induced, inhibitory effects on A549 cell viability.

scholarly journals Epigallocatechingallate Inhibits Migration of Human Uveal Melanoma Cells via Downregulation of Matrix Metalloproteinase-2 Activity and ERK1/2 Pathway

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Chi-Wu Chang ◽  
Yi-Hsien Hsieh ◽  
Wei-En Yang ◽  
Shun-Fa Yang ◽  
Yueqin Chen ◽  
...  
Keyword(s):  
Western Blot ◽  
Uveal Melanoma ◽  
Gelatin Zymography ◽  
Melanoma Cells ◽  
Matrix Metalloproteinase 2 ◽  
Pcr Analysis ◽  
Signal Pathways ◽  
Mrna Levels ◽  
Dependent Manner ◽  
Uveal Melanoma Cell

The effects of epigallocatechingallate (EGCG) on the migration and expression of MMP-2 of uveal melanoma cells have not been reported. We studied this effect and relevant signaling pathways in a human uveal melanoma cell line (M17). MTT study found that EGCG did not affect the cell viability of M17 cells up to 100 µM. Wound-healing assay showed that EGCG significantly reduced the migration of melanoma cells in a dose-dependent manner from 20 to 100 µM. Gelatin zymography showed that secreted MMP-2 activity was dose-dependently inhibited by EGCG, whereas the MMP-2 expression at protein and mRNA levels was not affected as determined by western blot and RT-PCR analysis. EGCG significantly increased the expressions of MMP-2 endogenous inhibitors (TIMP-2 and RECK) in M17 cells. Western blot analysis of MAPK signal pathways showed that EGCG significantly decreased phosphorylated ERK1/2 levels, but not p38 and JNK levels, in melanoma cells. ERK1/2 inhibitors also reduced the migration and activity of MMP-2 in M17 cells. The present study suggested EGCG at nontoxic levels could inhibit migration of melanoma cells via downregulation of activities of secreted MMP-2 through the inhibition of the ERK1/2 phosphorylation. Therefore, EGCG may be a promising agent to be explored for the prevention of metastasis of uveal melanoma.

Effect of freezing-thawing on the expression of mannose-ligand receptors on human spermatozoa: the impact on sperm capacitation and acrosome reaction

Andrologia ◽  
2001 ◽  
Vol 33 (5) ◽  
pp. 272-276 ◽  
Author(s):  
H. Yavetz ◽  
Y. Rosenblat ◽  
L. Yogev ◽  
A. Botchan ◽  
J. B. Lessing ◽  
...  
Keyword(s):  
Acrosome Reaction ◽  
Human Spermatozoa ◽  
Sperm Capacitation ◽  
Ligand Receptors ◽  
The Impact

Naked Poly(amidoamine) Dendrimer Nanoparticles Exhibit Intrinsic Embryotoxicity During the Early Stages of Normal Development

2020 ◽  
Vol 16 (10) ◽  
pp. 1454-1462
Author(s):  
Hadeel Kheraldine ◽  
Ishita Gupta ◽  
Hashim Alhussain ◽  
Ayesha Jabeen ◽  
Saghir Akhtar ◽  
...  
Keyword(s):  
Normal Development ◽  
Chorioallantoic Membrane ◽  
Pamam Dendrimers ◽  
Pcr Analysis ◽  
Dependent Manner ◽  
Rt Pcr ◽  
Future Studies ◽  
Early Stages ◽  
Expression Of Genes ◽  
The Impact

To investigate the impact of poly(amidoamine) dendrimers (PAMAMs) in the embryo, we explored the outcome of different generations (G4 and G6) on the early stages of embryogenesis using the chicken embryo as a model. We also monitored their effect on angiogenesis in the chorioallantoic membrane (CAM). Our data revealed that cationic PAMAMs provoke substantial embryotoxicity, as they significantly induce death (up to 50%, p < 0 05) and inhibit angiogenesis of the CAM (up to 30%, p < 0 05) in a generation-dependent manner in comparison to controls and other types of PAMAMs (anionic and neutral). Moreover, cationic PAMAMs alter the expression of genes related to cell survival, cell cycle, proliferation, transcription factor, apoptosis, and angiogenesis, as shown by RT-PCR analysis. Our data suggest that PAMAM dendrimers exhibit intrinsic toxicity in embryos at the early stages and inhibits angiogenesis of the CAM. Thus, future studies are necessary to illustrate the exact mechanism of PAMAM dendrimers in embryotoxicity.

Cytochrome c release into cytosol with subsequent caspase activation during warm ischemia in rat liver

2001 ◽  
Vol 281 (4) ◽  
pp. G1115-G1123 ◽  
Author(s):  
Junpei Soeda ◽  
Shinichi Miyagawa ◽  
Kenji Sano ◽  
Junya Masumoto ◽  
Shun'Ichiro Taniguchi ◽  
...  
Keyword(s):  
Cytochrome C ◽  
Dna Fragmentation ◽  
Warm Ischemia ◽  
Terminal Deoxynucleotidyl Transferase ◽  
Dependent Manner ◽  
Mitochondrial Cytochrome ◽  
Caspase Activation ◽  
Cytochrome C Release ◽  
Apoptotic Pathway ◽  
Mitochondrial Cytochrome C

Apoptosis plays an important role in liver ischemia and reperfusion (I/R) injury. However, the molecular basis of apoptosis in I/R injury is poorly understood. The aims of this study were to ascertain when and how apoptotic signal transduction occurs in I/R injury. The apoptotic pathway in rats undergoing 90 min of warm ischemia with reperfusion was compared with that of rats undergoing prolonged ischemia alone. During ischemia, mitochondrial cytochrome c was released into the cytosol in a time-dependent manner in hepatocytes and sinusoidal endothelial cells, and caspase-3 and an inhibitor of caspase-activated DNase were cleaved. However, apoptotic manifestation and DNA fragmentation were not observed. After reperfusion, nuclear condensation, cells positive for terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling, and DNA fragmentation were observed and caspase-8 and Bid cleavage occurred. In contrast, prolonged ischemia alone induced necrosis rather than apoptosis. In summary, our results show that release of mitochondrial cytochrome c and caspase activation proceed during ischemia, although apoptosis is manifested after reperfusion.

Abstract 576: Salicylamine, A γ-ketoaldehyde Scavenger, Improves HDL Function and Reduces Atherosclerosis in Apoe Deficient Mice

2017 ◽  
Vol 37 (suppl_1) ◽  
Author(s):  
Jiansheng Huang ◽  
Patricia Yancey ◽  
Lei Ding ◽  
Youmin Zhang ◽  
John Oates ◽  
...  
Keyword(s):  
Western Blot ◽  
Cholesterol Efflux ◽  
Adduct Formation ◽  
Molar Ratio ◽  
Atherosclerotic Cardiovascular Disease ◽  
Dependent Manner ◽  
Cholesterol Accumulation ◽  
Cholesterol Efflux Capacity ◽  
Hdl Function ◽  
The Impact

Background: Lipid peroxidation products impair the cholesterol efflux capacity of high-density lipoprotein (HDL) and promote the development of atherosclerosis. The impact of inhibition of malondialdehyde (MDA)-HDL adduct formation by scavengers on HDL function and whether small molecule aldehyde scavengers protect against the development of atherosclerosis was examined. Methods and Results: Western blot analysis of ApoAI revealed that the amount of ApoAI crosslinking increased with MDA concentration. In the presence of LPS, MDA-HDL (HDL modified by 1mM MDA) versus control HDL stimulated 2- and 1.8-fold more expression of TNF-α and IL-1β in Apoe-/- macrophages demonstrating that MDA-HDL has reduced anti-inflammatory function. HDL-mediated macrophage cholesterol efflux was decreased by ~ 42%, 55%, 70%, and 80%, respectively, for HDL modified with 0.125 mM, 0.25 mM, 0.5 mM, and 1mM MDA, demonstrating that MDA modification of HDL affects its cholesterol efflux capacity in a dose dependent manner. Analysis by Western blot demonstrated that 5mM of salicylamine (SAM) and 5mM of pentylpyridoxamine (PPM), γ-ketoaldehyde scavengers, attenuated MDA mediated crosslinking of apoA-I in HDL (molar ratio of MDA and HDL is 1:5) by 60% and 80 % (P<0.05), respectively. Both SAM and PPM maintained the cholesterol efflux capacity of MDA treated HDL in Apoe-/- macrophages. In addition, pretreatment of LDL with SAM prevented MDA-ApoB adduct formation, and compared to incubation with LDL containing MDA-ApoB adducts, SAM treatment resulted in 57% less cholesterol accumulation in J774 macrophages. Importantly, administration of the ketoaldehyde scavenger, SAM, versus the nonreactive analogue, 4-SAM, to Apoe-/- mice consuming a Western diet for 16 weeks reduced the extent of proximal aortic atherosclerosis by 28% (P<0.05). Conclusions: Treatment with salicylamine, a γ-ketoaldehyde scavenger: 1) inhibits MDA-ApoA1 adduct formation thereby preserving HDL cholesterol efflux capacity; 2) prevents MDA-apoB100 formation resulting in less macrophage cholesterol accumulation; 3) reduces atherosclerosis in Apoe -/- mice. These results support the therapeutic potential of salicylamine in the treatment of atherosclerotic cardiovascular disease.

scholarly journals Sevoflurane-Induced miR-211-5p Promotes Neuronal Apoptosis by Inhibiting Efemp2

ASN NEURO ◽  
2021 ◽  
Vol 13 ◽  
pp. 175909142110350
Author(s):  
Yousu Shen ◽  
Tao Zhou ◽  
Xiaobing Liu ◽  
Yanlong Liu ◽  
Yaqi Li ◽  
...  
Keyword(s):  
Cognitive Impairment ◽  
Neuronal Apoptosis ◽  
Matrix Protein ◽  
Extracellular Matrix Protein ◽  
Inflammatory Factor ◽  
Dependent Manner ◽  
Apoptotic Pathway ◽  
The Impact

Sevoflurane exposure can result in serious neurological side effects including neuronal apoptosis and cognitive impairment. Although the microRNA miR-211-5p is profoundly upregulated following sevoflurane exposure in neonatal rodent models, the impact of miR-211-5p on neuronal apoptosis and cognitive impairment postsevoflurane exposure has not yet been elucidated. Here, we found that sevoflurane upregulated miR-211-5p and downregulated EGF-Containing Fibulin Extracellular Matrix Protein 2 (Efemp2, Fibulin-4) levels in vitro and in vivo. Sevoflurane's effect on miR-211-5p expression was based on enhancing primary miR-211 transcription. miR-211-5p targets Efemp2's mRNA 3′-untranslated region, reducing Efemp2 expression. RNA immunoprecipitation revealed significant enrichment of the miR-211-5p:Efemp2 mRNA dyad in the RNA-induced silencing complex. miR-211-5p mimics downregulated Efemp2, leading to phosphorylation of Smad2 and Smad3, upregulation of pro-apoptotic Bim, and mitochondrial release of allograft inflammatory factor 1 and cytochrome C. In contrast, miR-211-5p hairpin inhibitor (AntimiR-211-5p) negatively regulated this apoptotic pathway and reduced neuronal apoptosis in an Efemp2-dependent manner. Sevoflurane-exposed mice administered AntimiR-211-5p displayed reduced cortical apoptosis levels and near-term cognitive impairment. In conclusion, sevoflurane-induced miR-211-5p promotes neuronal apoptosis via Efemp2 inhibition. Summary statement: This study revealed the significance of sevoflurane-induced increases in miR-211-5p on the promotion of neuronal apoptosis via inhibition of Efemp2 and its downstream targets.

scholarly journals Caspase Activation by Adenovirus E4orf4 Protein Is Cell Line Specific and Is Mediated by the Death Receptor Pathway

2001 ◽  
Vol 75 (2) ◽  
pp. 789-798 ◽  
Author(s):  
Adi Livne ◽  
Ronit Shtrichman ◽  
Tamar Kleinberger
Keyword(s):  
Death Receptor ◽  
Dominant Negative ◽  
Disulfonic Acid ◽  
Ros Generation ◽  
Caspase 8 ◽  
Dependent Manner ◽  
Caspase Activation ◽  
Apoptotic Pathway ◽  
Death Receptor Pathway ◽  
Induced Apoptosis

ABSTRACT Adenovirus E4orf4 protein has been shown to induce transformed cell-specific, protein phosphatase 2A-dependent, and p53-independent apoptosis. It has been further reported that the E4orf4 apoptotic pathway is caspase-independent in CHO cells. Here, we show that E4orf4 induces caspase activation in the human cell lines H1299 and 293T. Caspase activation is required for apoptosis in 293T cells, but not in H1299 cells. Dominant negative mutants of caspase-8 and the death receptor adapter protein FADD/MORT1 inhibit E4orf4-induced apoptosis in 293T cells, suggesting that E4orf4 activates the death receptor pathway. Cytochrome c is released into the cytosol in E4orf4-expressing cells, but caspase-9 is not required for induction of apoptosis. Furthermore, E4orf4 induces accumulation of reactive oxygen species (ROS) in a caspase-8- and FADD/MORT1-dependent manner, and inhibition of ROS generation by 4,5-dihydroxy-1,3-benzene-disulfonic acid (Tiron) inhibits E4orf4-induced apoptosis. Thus, our results demonstrate that E4orf4 engages the death receptor pathway to generate at least part of the molecular events required for E4orf4-induced apoptosis.

scholarly journals The Impact of Photoperiod on the Leptin Sensitivity and Course of Inflammation in the Anterior Pituitary

2020 ◽  
Vol 21 (11) ◽  
pp. 4153 ◽  
Author(s):  
Maciej Wójcik ◽  
Andrzej Przemysław Herman ◽  
Dorota Anna Zieba ◽  
Agata Krawczyńska
Keyword(s):  
Proinflammatory Cytokines ◽  
Anterior Pituitary ◽  
Leptin Resistance ◽  
Pcr Analysis ◽  
Dependent Manner ◽  
In Vivo Experiments ◽  
Leptin Sensitivity ◽  
The Impact ◽  
Short Days

Leptin has a modulatory impact on the course of inflammation, affecting the expression of proinflammatory cytokines and their receptors. Pathophysiological leptin resistance identified in humans occurs typically in sheep during the long-day photoperiod. This study aimed to determine the effect of the photoperiod with relation to the leptin-modulating action on the expression of the proinflammatory cytokines and their receptors in the anterior pituitary under physiological or acute inflammation. Two in vivo experiments were conducted on 24 blackface sheep per experiment in different photoperiods. The real-time PCR analysis for the expression of the genes IL1B, IL1R1, IL1R2, IL6, IL6R, IL6ST, TNF, TNFR1, and TNFR2 was performed. Expression of all examined genes, except IL1β and IL1R2, was higher during short days. The leptin injection increased the expression of all examined genes during short days. In short days the synergistic effect of lipopolysaccharide and leptin increased the expression of IL1B, IL1R1, IL1R2, IL6, TNF, and TNFR2, and decreased expression of IL6ST. This mechanism was inhibited during long days for the expression of IL1R1, IL6, IL6ST, and TNFR1. The obtained results suggest the occurrence of leptin resistance during long days and suggest that leptin modulates the course of inflammation in a photoperiod-dependent manner in the anterior pituitary.

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