In Vivo and In Vitro Analyses of Novel Peptidomimetic Disruptors for the Serotonin 5-HT2C Receptor Interaction With Phosphatase and Tensin Homolog

Cardiac fibrosis has been known to play an important role in the etiology of heart failure after myocardial infarction (MI). B lymphoma Mo-MLV insertion region 1 homolog (BMI1), a transcriptional repressor, is important for fibrogenesis in the kidneys. However, the effect of BMI1 on ischemia-induced cardiac fibrosis remains unclear. BMI1 was strongly expressed in the infarct region 1 wk post-MI in mice and was detected by Western blot and histological analyses. Lentivirus-mediated overexpression of BMI1 significantly promoted cardiac fibrosis, worsened cardiac function 4 wk after the intervention in vivo, and enhanced the proliferation and migration capabilities of fibroblasts in vitro , whereas downregulation of BMI1 decreased cardiac fibrosis and prevented cardiac dysfunction in mice 4 wk post-MI in vivo. Furthermore, upregulated BMI1 inhibited phosphatase and tensin homolog (PTEN) expression, enhanced phosphatidylinositol 3-kinase (PI3K) expression, and increased the phosphorylation level of Akt and mammalian target of rapamycin (mTOR) in mice 4 wk after lentiviral infection, which was in accordance with the changes seen in their infarcted myocardial tissues. At the same time, the effects of BMI1 on cardiac fibroblasts were reversed in vitro when these cells were exposed to NVP-BEZ235, a dual-kinase (PI3K/mTOR) inhibitor. In conclusion, BMI1 is associated with cardiac fibrosis and dysfunction after MI by regulating cardiac fibroblast proliferation and migration, and these effects could be partially explained by the regulation of the PTEN-PI3K/Akt-mTOR pathway. NEW & NOTEWORTHY Ischemia-induced B lymphoma Mo-MLV insertion region 1 homolog (BMI1) significantly promoted cardiac fibrosis and worsened cardiac function in vivo, whereas downregulation of BMI1 decreased cardiac fibrosis and prevented cardiac dysfunction in myocardial infarcted mice. BMI1 also enhanced proliferation and migration capabilities of fibroblasts in vitro; these effects were reversed by NVP-BEZ235. Effects of BMI1 on cardiac fibrosis could be partially explained by regulation of the phosphatase and tensin homolog-phosphatidylinositol 3-kinase/Akt-mammalian target of rapamycin pathway.

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Podocyte-specific knockin of PTEN protects kidney from hyperglycemia

AJP Renal Physiology ◽

10.1152/ajprenal.00575.2017 ◽

2018 ◽

Vol 314 (6) ◽

pp. F1096-F1107 ◽

Cited By ~ 10

Author(s):

Huizhen Wang ◽

Ziwei Feng ◽

Jianteng Xie ◽

Feng Wen ◽

Menglei Jv ◽

...

Keyword(s):

Diabetic Kidney Disease ◽

Therapeutic Strategy ◽

Renal Protection ◽

Phosphatase And Tensin Homolog ◽

Tensin Homolog ◽

Matrix Expansion ◽

Interfering Rna

Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) has proven to be downregulated in podocytes challenged with high glucose (HG), and knockout of PTEN in podocytes aggravated the progression of diabetic kidney disease (DKD). However, whether podocyte-specific knockin of PTEN protects the kidney against hyperglycemia in vivo remains unknown. The inducible podocyte-specific PTEN knockin (PPKI) mice were generated by crossing newly created transgenic loxP-stop- loxP-PTEN mice with podocin-iCreERT2 mice. Diabetes mellitus was induced in mice by intraperitoneal injection of streptozotocin at a dose of 150 mg/kg. In vitro, small interfering RNA and adenovirus interference were used to observe the role of PTEN in HG-treated podocytes. Our data demonstrated that PTEN was markedly reduced in the podocytes of patients with DKD and focal segmental glomerulosclerosis, as well as in those of db/db mice. Interestingly, podocyte-specific knockin of PTEN significantly alleviated albuminuria, mesangial matrix expansion, effacement of podocyte foot processes, and incrassation of glomerular basement membrane in diabetic PPKI mice compared with wild-type diabetic mice, whereas no alteration was observed in the level of blood glucose. The potential renal protection of overexpressed PTEN in podocytes was partly attributed with an improvement in autophagy and motility and the inhibition of apoptosis. Our results showed that podocyte-specific knockin of PTEN protected the kidney against hyperglycemia in vivo , suggesting that targeting PTEN might be a novel and promising therapeutic strategy against DKD.

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Loss of phosphatase and tensin homolog (PTEN) in myeloid cells controls inflammatory bone destruction by regulating the osteoclastogenic potential of myeloid cells

Annals of the Rheumatic Diseases ◽

10.1136/annrheumdis-2013-203486 ◽

2013 ◽

Vol 74 (1) ◽

pp. 227-233 ◽

Cited By ~ 26

Author(s):

Stephan Blüml ◽

Martin Friedrich ◽

Tobias Lohmeyer ◽

Emine Sahin ◽

Victoria Saferding ◽

...

Keyword(s):

Myeloid Cells ◽

Bone Destruction ◽

Precursor Cells ◽

Nuclear Factor ◽

Phosphatase And Tensin Homolog ◽

Tensin Homolog ◽

Inflammatory Conditions ◽

Local Bone

ObjectiveLocal bone destruction in rheumatic diseases, which often leads to disability and severely reduced quality of life, is almost exclusively mediated by osteoclasts. Therefore, it is important to understand pathways regulating the generation of osteoclasts. Here, we analysed the impact of the Phosphoinositide-3-Kinase (PI3K)/Phosphatase and tensin homolog (PTEN) axis on osteoclast generation and bone biology under basal and inflammatory conditions.MethodsWe analysed osteoclastogenesis of wildtype (wt) and PTEN−/− cells in vitro and in vivo, pit resorption and qPCR of osteoclasts in vitro. Mice with a myeloid cell-specific deletion of PTEN and wt littermate mice were investigated by bone histomorphometry and clinical and histological assessment in the human tumour necrosis factor (TNF)-transgenic (hTNFtg) arthritis model.ResultsWe show that myeloid-specific PTEN−/− mice display increased osteoclastogenesis in vitro and in vivo compared to wt mice. Loss of PTEN did not affect the generation or survival of osteoclast precursor cells. However, PTEN deficiency greatly enhanced receptor activator of nuclear factor κ-B ligand (RANKL)-induced expression of the master transcription factor of osteoclastogenesis, nuclear factor of activated T-cells, cytoplasmic 1 (NFATc1), resulting in markedly increased terminal differentiation of osteoclasts in vitro. We also observed increased osteoclastogenesis under inflammatory conditions in the hTNFtg mouse model of arthritis, where hTNFtg/myeloid-specific PTEN−/− mice displayed enhanced local bone destruction as well as osteoclast formation in the inflamed joints. The extent of synovial inflammation, however, as well as recruitment of osteoclast precursor cells was not different between wt and myeloid-specific PTEN−/− mice.ConclusionsThese data demonstrate that loss of PTEN and, therefore, sustained PI3-Kinase signalling in myeloid cells especially, elevates the osteoclastogenic potential of myeloid cells, leading to enhanced inflammatory local bone destruction. Therefore, although our study allows no direct translational conclusion since we used a conditional knockout approach, the therapeutic targeting of the PI3-Kinase pathway may be of benefit in preventing structural joint damage.

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The Antioxidant from Ethanolic Extract of Rosa cymosa Fruits Activates Phosphatase and Tensin Homolog In Vitro and In Vivo: A New Insight on Its Antileukemic Effect

International Journal of Molecular Sciences ◽

10.3390/ijms20081935 ◽

2019 ◽

Vol 20 (8) ◽

pp. 1935 ◽

Cited By ~ 1

Author(s):

Kuan-Chih Wang ◽

Yi-Chang Liu ◽

Mohamed El-Shazly ◽

Shou-Ping Shih ◽

Ying-Chi Du ◽

...

Keyword(s):

Calcium Release ◽

Herbal Remedy ◽

Lymphoblastic Leukemia ◽

Ethanolic Extract ◽

Control Group ◽

Ros Generation ◽

Phosphatase And Tensin Homolog ◽

Tensin Homolog

Rosa cymosa Tratt is a Chinese herbal remedy that is used in the treatment of diarrhea, burns, rheumatoid arthritis, and hemorrhage. Despite its use in Asian folk medicine, there are limited reports on the biological activity of R. cymosa fruits. This study focused on the investigation of the antitumor effect of the antioxidative ethanolic extract of R. cymosa fruits (RCE) along with its underlying mechanism of action. RCE showed a potent cytotoxic effect against Sup-T1 and Molt-4 lymphoblastic leukemia cells. In the xenograft animal model, the tumor size was significantly reduced to about 59.42% in the RCE-treated group in comparison with the control group. The use of RCE (37.5, 75, or 150 μg/mL) triggered apoptosis by 26.52–83.49%, disrupted mitochondrial membrane potential (MMP) by 10.44–58.60%, and promoted calcium release by 1.29-, 1.44-, and 1.71-fold compared with the control group. The extract induced redox oxygen species (ROS) generation through the elimination of Nrf2/Keap1/P62-mediated oxidative stress response. The loss of phosphatase and tensin homolog (PTEN) activation by RCE impaired PI3K/Akt/Foxo and Jak/Stat activation pathways, which contributed to tumorigenesis. These multiple targets of R. cymosa against hematologic cancer cells suggested its potential application as an antileukemic dietary supplement.

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Levosimendan Protects against Doxorubicin-Induced Cardiotoxicity by Regulating the PTEN/Akt Pathway

BioMed Research International ◽

10.1155/2020/8593617 ◽

2020 ◽

Vol 2020 ◽

pp. 1-11

Author(s):

Ling-Li Li ◽

Li Wei ◽

Ning Zhang ◽

Wen-Ying Wei ◽

Can Hu ◽

...

Keyword(s):

Critical Role ◽

Cardiac Injury ◽

Protective Role ◽

Akt Inhibitor ◽

Morphological Examination ◽

Phosphatase And Tensin Homolog ◽

Tensin Homolog ◽

Myocardial Apoptosis

Background and Aims. Myocyte apoptosis plays a critical role in the development of doxorubicin- (DOX-) induced cardiotoxicity. In addition to its cardiotonic effect, laboratory evidence indicates that levosimendan can inhibit apoptosis, but its role in DOX-induced cardiac injury remains unclear. Therefore, the present study is aimed at exploring whether levosimendan could attenuate DOX-induced cardiotoxicity. Methods. Levosimendan (1 mg/kg) was administered to mice through oral gavage once daily for 4 weeks, and the mice were also subjected to an intraperitoneal injection of DOX (5 mg/kg) or saline, once a week for 4 weeks, to create a chronic model of DOX-induced cardiotoxicity. A morphological examination and biochemical analysis were used to evaluate the effects of levosimendan. H9C2 cells were used to verify the protective role of levosimendan in vitro. And an Akt inhibitor was utilized to verify the cardioprotection of levosimendan. Results. Levosimendan reduced the cardiac dysfunction and attenuated the myocardial apoptosis induced by DOX in vivo and in vitro. Levosimendan also inhibited the activation of phosphatase and tensin homolog (PTEN) and upregulated P-Akt expression both in vivo and in vitro. And inhibition of Akt abolished the cardioprotection of levosimendan in vitro. Conclusion. Levosimendan may protect against DOX-induced cardiotoxicity via modulation of the PTEN/Akt signaling pathway.

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In vitro and in vivo anti-malignant melanoma activity of Alocasia cucullata via modulation of the phosphatase and tensin homolog/phosphoinositide 3-kinase/AKT pathway

Journal of Ethnopharmacology ◽

10.1016/j.jep.2017.11.025 ◽

2018 ◽

Vol 213 ◽

pp. 359-365 ◽

Cited By ~ 4

Author(s):

Miao Fang ◽

Daoqi Zhu ◽

Chaohua Luo ◽

Chan Li ◽

Chen Zhu ◽

...

Keyword(s):

Malignant Melanoma ◽

Akt Pathway ◽

Phosphatase And Tensin Homolog ◽

Tensin Homolog ◽

Phosphoinositide 3 Kinase ◽

Alocasia Cucullata

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Expression of microRNA during bovine adipogenesis

Journal of Nucleic Acids Investigation ◽

10.4081/jnai.2010.1872 ◽

2010 ◽

Vol 1 (1) ◽

pp. 12 ◽

Cited By ~ 1

Author(s):

Scott L. Pratt ◽

T. Ashley Burns ◽

Erin Curry ◽

Susan K. Duckett

Keyword(s):

Messenger Rna ◽

Differentially Expressed ◽

Transcriptional Level ◽

Messenger Rnas ◽

Phosphatase And Tensin Homolog ◽

Tensin Homolog ◽

Expression Of Genes ◽

Bovine Adipocytes

Studies have recently indicated that the adipogenic process and the expression of genes involved in lipid metabolism may be regulated in part at the post-transcriptional level by a class of small RNA called microRNA (miRNA). The objectives of this study were to i) determine if miRNAs are differentially expressed, and ii) evaluate expression of known miRNA targets in bovine adipocytes. Bovine adipose samples were collected from castrated males fattened on a high concentrate diet (C) or pasture (PA) and were frozen in liquid nitrogen and stored at -80°C, or used to generate primary stromal-vascular cells (SV). SV cells were cultured to confluence (Control) or differentiated at confluence and harvested 2 (D2), 6 (D6), or 12 (D12) days post-confluence. A 3x3 microarray analysis was performed comparing Control and differentiated samples. miR-21, -221, and -222 (P less than 0.05) were differentially expressed. qRT-PCR was conducted using the in vitro samples, and all three miRNAs were down regulated on D2 (P less than 0.05). miR-221 and -222 were decreased on D6 compared to Control (P less than 0.05), but only miR-222 expression was decreased at D12 (P less than 0.05) compared to Control. miR-21 increased in expression compared to Control on D12 (P less than 0.05). In vivo, only miR-21 expression was affected and it was reduced in PA compared to C fat samples (P less than 0.05). Two targets of miR-21 are Programmed Cell Death Protein 4 (PDCD4) and Phosphatase and Tensin Homolog (PTEN), and neither messenger RNA was differentially expressed in vitro (P greater than 0.05), but both messenger RNAs were elevated for PA compared to C (P less than 0.05). These data show that miRNAs are differentially expressed in adipose cells and tissue, and that miR-21 may be involved in adipocyte function by regulating the translation of PDCD4 and PTEN.

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LINC00470 Stimulates Methylation of PTEN to Facilitate the Progression of Endometrial Cancer by Recruiting DNMT3a Through MYC

Frontiers in Oncology ◽

10.3389/fonc.2021.646217 ◽

2021 ◽

Vol 11 ◽

Author(s):

Tiezhong Yi ◽

Yicun Song ◽

Lingling Zuo ◽

Siyun Wang ◽

Jintian Miao

Keyword(s):

Endometrial Cancer ◽

Tube Formation ◽

Loss Of Function ◽

Phosphatase And Tensin Homolog ◽

Tensin Homolog ◽

Kaplan Meier ◽

Ec Cells ◽

Non Coding Rnas

ObjectivesIncreasing researches emphasize the importance of long non-coding RNAs (lncRNAs) in the development of endometrial cancer (EC). There is wide recognition that LINC00470 is a critical participant in the tumorigenesis of cancers such as gastric cancer and glioblastoma, but its possible effects on EC progression remain to be explored.MethodsWe collected EC tissues and cells, where the expression of LINC00470 was determined, and followed by the Kaplan-Meier analysis of EC patient survival. We next examined the effect of LINC00470 and phosphatase and tensin homolog (PTEN) on EC cell migration, invasion, tube formation in vitro, and angiogenesis in mice xenografted with tumor after gain- or loss-of-function treatments. RNA pull-down, Co-IP, and ChIP experiments were performed to analyze the targeting relationships among LINC00470, MYC and DNMT3a.ResultsLINC00470 was aberrantly upregulated in EC and its high expression correlated to prognosis of EC patients. LINC00470 promoted invasiveness, migration, and angiogenesis of EC cells, and facilitated tumorigenesis and metastasis in vivo, but those effects were reversed by up-regulating PTEN. Functionally, LINC00470 bound to MYC in EC and that LINC00470 stimulated the binding of MYC to DNMT3a, and thus recruited DNMT3a through MYC to promote PTEN methylation.ConclusionsOur findings revealed that LINC00470 stimulated PTEN methylation to inhibit its expression by MYC-induced recruitment of DNMT3a, thus aggravating EC.

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Hepatic HuR protects against the pathogenesis of non-alcoholic fatty liver disease by targeting PTEN

Cell Death and Disease ◽

10.1038/s41419-021-03514-0 ◽

2021 ◽

Vol 12 (3) ◽

Author(s):

Mi Tian ◽

Jingjing Wang ◽

Shangming Liu ◽

Xinyun Li ◽

Jingyuan Li ◽

...

Keyword(s):

Glucose Metabolism ◽

Hepatic Steatosis ◽

Chow Diet ◽

Alcoholic Fatty Liver ◽

Phosphatase And Tensin Homolog ◽

Tensin Homolog ◽

Pten Mrna ◽

Normal Chow ◽

Mice Liver

AbstractThe liver plays an important role in lipid and glucose metabolism. Here, we show the role of human antigen R (HuR), an RNA regulator protein, in hepatocyte steatosis and glucose metabolism. We investigated the level of HuR in the liver of mice fed a normal chow diet (NCD) and a high-fat diet (HFD). HuR was downregulated in the livers of HFD-fed mice. Liver-specific HuR knockout (HuRLKO) mice showed exacerbated HFD-induced hepatic steatosis along with enhanced glucose tolerance as compared with control mice. Mechanistically, HuR could bind to the adenylate uridylate-rich elements of phosphatase and tensin homolog deleted on the chromosome 10 (PTEN) mRNA 3′ untranslated region, resulting in the increased stability of Pten mRNA; genetic knockdown of HuR decreased the expression of PTEN. Finally, lentiviral overexpression of PTEN alleviated the development of hepatic steatosis in HuRLKO mice in vivo. Overall, HuR regulates lipid and glucose metabolism by targeting PTEN.

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Abstract 37: Nrip Deficiency Leads to Dilated Cardiomyopathy

Circulation Research ◽

10.1161/res.117.suppl_1.37 ◽

2015 ◽

Vol 117 (suppl_1) ◽

Author(s):

Show-Li Chen

Keyword(s):

Calcium Transient ◽

Receptor Interaction ◽

Cell Width ◽

Interacting Protein ◽

Cardiac Tissues ◽

Calmodulin Binding ◽

Calcineurin Phosphatase ◽

And Function

Previously, we demonstrate a gene, nuclear receptor interaction protein (NRIP, also named DCAF6 or IQWD1) as a Ca2+- dependent calmodulin binding protein that can activate calcineurin phosphatase activity. Here, we found that α-actinin-2 (ACTN2), is one of NRIP-interacting proteins from the yeast two-hybrid system using NRIP as a prey. We further confirmed the direct bound between NRIP and ACTN2 using in vitro protein-protein interaction and in vivo co-immunoprecipitation assays. To further map the binding domain of each protein, the results showed the IQ domain of NRIP responsible for ACTN2 binding, and EF hand motif of ACTN2 responsible for NRIP bound. Due to ACTN2 is a biomarker of muscular Z-disc complex; we found the co-localization of NRIP and ACTN2 in cardiac tissues by immunofluorescence assays. Taken together, NRIP is a novel ACTN2-interacting protein. To investigate insights into in vivo function of NRIP, we generated conventional NRIP-null mice. The H&E staining results are shown in the hearts of NRIP KO mice are enlarged and dilated and the cell width of NRIP KO cardiomyocyte is increased. The EM of NRIP KO heart muscles reveal the reduction of I-band width and extension length of Z-disc in sarcomere structure; and the echocardiography shows the diminished fractional shortening in heart functions. Additionally, the calcium transient and sarcomere contraction length in cardiomyocytes of NRIP KO is weaker and shorter than wt; respectively. In conclusion, NRIP is a novel Z-disc protein and has function for maintenance of sarcomere integrity structure and function for calcium transient and muscle contraction.

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