Neural FoxP2 and FoxP1 expression in the budgerigar, an avian species with adult vocal learning

PubMed Central

Hara, Erina; Perez, Jemima M.; Whitney, Osceola; Chen, Qianqian; White, Stephanie A.; Wright, Timothy F.

2015-01-01

Vocal learning underlies acquisition of both language in humans and vocal signals in some avian taxa. These bird groups and humans exhibit convergent developmental phases and associated brain pathways for vocal communication. The transcription factor FoxP2 plays critical roles in vocal learning in humans and songbirds. Another member of the forkhead box gene family, FoxP1 also shows high expression in brain areas involved in vocal learning and production. Here, we investigate FoxP2 and FoxP1 mRNA and protein in adult male budgerigars (Melopsittacus undulatus), a parrot species that exhibits vocal learning as both juveniles and adults. To examine these molecules in adult vocal learners, we compared their expression patterns in the budgerigar striatal nucleus involved in vocal learning, magnocellular nucleus of the medial striatum (MMSt), across birds with different vocal states, such as vocalizing to a female (directed), vocalizing alone (undirected), and non-vocalizing. We found that both FoxP2 mRNA and protein expressions were consistently lower in MMSt than in the adjacent striatum regardless of the vocal states, whereas previous work has shown that songbirds exhibit downregulation in the homologous region, Area X, only after singing alone. In contrast, FoxP1 levels were high in MMSt compared to the adjacent striatum in all groups. Taken together these results strengthen the general hypothesis that FoxP2 and FoxP1 have specialized expression in vocal nuclei across a range of taxa, and suggest that the adult vocal plasticity seen in budgerigars may be a product of persistent down-regulation of FoxP2 in MMSt. PMID:25601574

Fox-2 Splicing Factor Binds to a Conserved Intron Motif to PromoteInclusion of Protein 4.1R Alternative Exon 16

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ponthier, Julie L.; Schluepen, Christina; Chen, Weiguo

Activation of protein 4.1R exon 16 (E16) inclusion during erythropoiesis represents a physiologically important splicing switch that increases 4.1R affinity for spectrin and actin. Previous studies showed that negative regulation of E16 splicing is mediated by the binding of hnRNP A/B proteins to silencer elements in the exon and that downregulation of hnRNP A/B proteins in erythroblasts leads to activation of E16 inclusion. This paper demonstrates that positive regulation of E16 splicing can be mediated by Fox-2 or Fox-1, two closely related splicing factors that possess identical RNA recognition motifs. SELEX experiments with human Fox-1 revealed highly selective binding tomore » the hexamer UGCAUG. Both Fox-1 and Fox-2 were able to bind the conserved UGCAUG elements in the proximal intron downstream of E16, and both could activate E16 splicing in HeLa cell co-transfection assays in a UGCAUG-dependent manner. Conversely, knockdown of Fox-2 expression, achieved with two different siRNA sequences resulted in decreased E16 splicing. Moreover, immunoblot experiments demonstrate mouse erythroblasts express Fox-2, but not Fox-1. These findings suggest that Fox-2 is a physiological activator of E16 splicing in differentiating erythroid cells in vivo. Recent experiments show that UGCAUG is present in the proximal intron sequence of many tissue-specific alternative exons, and we propose that the Fox family of splicing enhancers plays an important role in alternative splicing switches during differentiation in metazoan organisms.« less

MicroRNA-630 Suppresses Epithelial-to-Mesenchymal Transition by Regulating FoxM1 in Gastric Cancer Cells.

PubMed

Feng, Jing; Wang, Xiaojuan; Zhu, Weihua; Chen, Si; Feng, Changwei

2017-06-01

In the present study, we investigated the functional role of microRNA (miR)-630 in epithelial-to-mesenchymal transition (EMT) of gastric cancer (GC) cells, as well as the regulatory mechanism. Cells of human GC cell line SGC 7901 were transfected with miR-630 mimic or miR-630 inhibitor. The transfection efficiency was confirmed by qRT-PCR. Cell migration and invasion were determined by Transwell assay. Protein expression of E-cadherin, vimentin, and Forkhead box protein M1 (FoxM1) was tested by Western blot. Moreover, the expression of FoxM1 was elevated or suppressed, and then the effects of miR-630 abnormal expression on EMT and properties of migration and invasion were examined again, as well as protein expression of Ras/phosphoinositide 3-kinase (PI3K)/AKT related factors. The results showed that (i) the EMT and properties of migration and invasion were statistically decreased by overexpression of miR-630 compared to the control group but markedly increased by suppression of miR-630. However, (ii) abnormal expression of FoxM1 reversed these effects in GC cells. Moreover, (iii) expression of GTP-Rac1, p-PI3K, and p-AKT was decreased by miR-630 overexpression but increased by FoxM1 overexpression. (iv) The decreased levels of GTP-Rac1, p-PI3K, and p-AKT induced by miR-630 overexpression were dramatically elevated by simultaneous overexpression of FoxM1. In conclusion, our results suggest that miR-630 might be a tumor suppressor in GC cells. MiR-630 suppresses EMT by regulating FoxM1 in GC cells, supposedly via inactivation of the Ras/PI3K/AKT pathway.

Cell-penetrable mouse forkhead box protein 3 alleviates experimental arthritis in mice by up-regulating regulatory T cells.

PubMed

Liu, Xia; Ji, Baoju; Sun, Mengyi; Wu, Weijiang; Huang, Lili; Sun, Aihua; Zong, Yangyong; Xia, Sheng; Shi, Liyun; Qian, Hui; Xu, Wenrong; Shao, Qixiang

2015-07-01

Regulatory T cells (T(regs)) have potential applications in clinical disease therapy, such as autoimmune diseases and transplant rejection. However, their numbers are limited. Forkhead box protein 3 (FoxP3) is a key transcription factor that controls T(reg) development and function. Here, we generated a cell-permeable fusion protein, protein transduction domain (PTD)-conjugated mouse FoxP3 protein (PTD-mFoxP3), and evaluated whether PTD-mFoxp3 can alleviate rheumatoid arthritis (RA) in the collagen-induced arthritis (CIA) mouse model. As expected, PTD-mFoxP3 was transduced into cells effectively, and inhibited T cell activation and attenuated the cell proliferation. It decreased interleukin (IL) 2 and interferon (IFN)-γ expression, and increased IL-10 expression in activated CD4(+)CD25(-) T cells. PTD-mFoxP3-transduced CD4(+)CD25(-) T cells attenuated proliferation of activated CD4(+)CD25(-) T cells. In addition, PTD-mFoxP3 blocked the Th17 differentiation programme in vitro and down-regulated IL-17 production from T cells by modulating induction and levels of retinoid-related orphan receptor gamma t (RORγt). Intra-articular delivery of PTD-mFoxP3 delayed disease incidence remarkably and alleviated autoimmune symptoms of CIA mice. Moreover, protective effects of PTD-mFoxP3 were associated with regulating the balance of T helper type 17 (Th17) and T(regs). These results suggest that PTD-mFoxP3 may be a candidate for RA therapy. © 2015 British Society for Immunology.

Differential coexpression of FoxP1, FoxP2, and FoxP4 in the Zebra Finch (Taeniopygia guttata) song system.

PubMed

Mendoza, Ezequiel; Tokarev, Kirill; Düring, Daniel N; Retamosa, Eva Camarillo; Weiss, Michael; Arpenik, Nshdejan; Scharff, Constance

2015-06-15

Heterozygous disruptions of the Forkhead transcription factor FoxP2 impair acquisition of speech and language. Experimental downregulation in brain region Area X of the avian ortholog FoxP2 disrupts song learning in juvenile male zebra finches. In vitro, transcriptional activity of FoxP2 requires dimerization with itself or with paralogs FoxP1 and FoxP4. Whether this is the case in vivo is unknown. To provide the means for future functional studies we cloned FoxP4 from zebra finches and compared regional and cellular coexpression of FoxP1, FoxP2, and FoxP4 mRNA and protein in brains of juvenile and adult male zebra finches. In the telencephalic song nuclei HVC, RA, and Area X, the three investigated FoxPs were either expressed alone or occurred in specific combinations with each other, as shown by double in situ hybridization and triple immunohistochemistry. FoxP1 and FoxP4 but not FoxP2 were expressed in RA and in the HVCRA and HVCX projection neurons. In Area X and the surrounding striatum the density of neurons expressing all three FoxPs together or FoxP1 and FoxP4 together was significantly higher than the density of neurons expressing other combinations. Interestingly, the proportions of Area X neurons expressing particular combinations of FoxPs remained constant at all ages. In addition, FoxP-expressing neurons in adult Area X express dopamine receptors 1A, 1B, and 2. Together, these data provide the first evidence that Area X neurons can coexpress all avian FoxP subfamily members, thus allowing for a variety of regulatory possibilities via heterodimerization that could impact song behavior in zebra finches. © 2014 Wiley Periodicals, Inc.

GCN5L1 modulates cross-talk between mitochondria and cell signaling to regulate FoxO1 stability and gluconeogenesis.

PubMed

Wang, Lingdi; Scott, Iain; Zhu, Lu; Wu, Kaiyuan; Han, Kim; Chen, Yong; Gucek, Marjan; Sack, Michael N

2017-09-12

The mitochondrial enriched GCN5-like 1 (GCN5L1) protein has been shown to modulate mitochondrial protein acetylation, mitochondrial content and mitochondrial retrograde signaling. Here we show that hepatic GCN5L1 ablation reduces fasting glucose levels and blunts hepatic gluconeogenesis without affecting systemic glucose tolerance. PEPCK and G6Pase transcript levels are downregulated in hepatocytes from GCN5L1 liver specific knockout mice and their upstream regulator, FoxO1 protein levels are decreased via proteasome-dependent degradation and via reactive oxygen species mediated ERK-1/2 phosphorylation. ERK inhibition restores FoxO1, gluconeogenic enzyme expression and glucose production. Reconstitution of mitochondrial-targeted GCN5L1 blunts mitochondrial ROS, ERK activation and increases FoxO1, gluconeogenic enzyme expression and hepatocyte glucose production. We suggest that mitochondrial GCN5L1 modulates post-translational control of FoxO1, regulates gluconeogenesis and controls metabolic pathways via mitochondrial ROS mediated ERK activation. Exploring mechanisms underpinning GCN5L1 mediated ROS signaling may expand our understanding of the role of mitochondria in gluconeogenesis control.Hepatic gluconeogenesis is tightly regulated at transcriptional level and is essential for survival during prolonged fasting. Here Wang et al. show that the mitochondrial enriched GCN5-like 1 protein controls hepatic glucose production by regulating FoxO1 protein levels via proteasome-dependent degradation and, in turn, gluconeogenic gene expression.

miR-182 attenuates atrophy-related gene expression by targeting FoxO3 in skeletal muscle

PubMed Central

Rahnert, Jill A.; Zheng, Bin; Woodworth-Hobbs, Myra E.; Franch, Harold A.; Russ Price, S.

2014-01-01

Skeletal muscle atrophy occurs in response to a variety of conditions including chronic kidney disease, diabetes, cancer, and elevated glucocorticoids. MicroRNAs (miR) may play a role in the wasting process. Activation of the forkhead box O3 (FoxO3) transcription factor causes skeletal muscle atrophy in patients, animals, and cultured cells by increasing the expression of components of the ubiquitin-proteasome and autophagy-lysosome proteolytic systems. To identify microRNAs that potentially modulate the atrophy process, an in silico target analysis was performed and miR-182 was predicted to target FoxO3 mRNA. Using a combination of immunoblot analysis, quantitative real-time RT-PCR, and FoxO3 3′-UTR luciferase reporter genes, miR-182 was confirmed to regulate FoxO3 expression in C2C12 myotubes. Transfection of miR-182 into muscle cells decreased FoxO3 mRNA 30% and FoxO3 protein 67% (P < 0.05) and also prevented a glucocorticoid-induced upregulation of multiple FoxO3 gene targets including MAFbx/atrogin-1, autophagy-related protein 12 (ATG12), cathepsin L, and microtubule-associated protein light chain 3 (LC3). Treatment of C2C12 myotubes with dexamethasone (Dex) (1 μM, 6 h) to induce muscle atrophy decreased miR-182 expression by 63% (P < 0.05). Similarly, miR-182 was decreased 44% (P < 0.05) in the gastrocnemius muscle of rats injected with streptozotocin to induce diabetes compared with controls. Finally, miR-182 was present in exosomes isolated from the media of C2C12 myotubes and Dex increased its abundance. These data identify miR-182 as an important regulator of FoxO3 expression that participates in the control of atrophy-inducing genes during catabolic diseases. PMID:24871856

Linking Alzheimer's disease to insulin resistance: the FoxO response to oxidative stress.

PubMed

Manolopoulos, K N; Klotz, L-O; Korsten, P; Bornstein, S R; Barthel, A

2010-11-01

Oxidative stress is an important determinant not only in the pathogenesis of Alzheimer's disease (AD), but also in insulin resistance (InsRes) and diabetic complications. Forkhead box class O (FoxO) transcription factors are involved in both insulin action and the cellular response to oxidative stress, thereby providing a potential integrative link between AD and InsRes. For example, the expression of intra- and extracellular antioxidant enzymes, such as manganese-superoxide dismutase and selenoprotein P, is regulated by FoxO proteins, as is the expression of important hepatic enzymes of gluconeogenesis. Here, we review the molecular mechanisms involved in the pathogenesis of AD and InsRes and discuss the function of FoxO proteins in these processes. Both InsRes and oxidative stress may promote the transcriptional activity of FoxO proteins, resulting in hyperglycaemia and a further increased production of reactive oxygen species (ROS). The consecutive activation of c-Jun N-terminal kinases and inhibition of Wingless (Wnt) signalling may result in the formation of β-amyloid plaques and τ protein phosphorylation. Wnt inhibition may also result in a sustained activation of FoxO proteins with induction of apoptosis and neuronal loss, thereby completing a vicious circle from oxidative stress, InsRes and hyperglycaemia back to the formation of ROS and consecutive neurodegeneration. In view of their central function in this model, FoxO proteins may provide a potential molecular target for the treatment of both InsRes and AD.

Genome-wide identification and characterization of Fox genes in the silkworm, Bombyx mori.

PubMed

Song, JiangBo; Li, ZhiQuan; Tong, XiaoLing; Chen, Cong; Chen, Min; Meng, Gang; Chen, Peng; Li, ChunLin; Xin, YaQun; Gai, TingTing; Dai, FangYin; Lu, Cheng

2015-09-01

The forkhead box (Fox) transcription factor family has a characteristic of forkhead domain, a winged DNA-binding domain. The Fox genes have been classified into 23 subfamilies, designated FoxA to FoxS, of which the FoxR and FoxS subfamilies are specific to vertebrates. In this review, using whole-genome scanning, we identified 17 distinct Fox genes distributed on 13 chromosomes of the silkworm, Bombyx mori. A phylogenetic tree showed that the silkworm Fox genes could be classified into 13 subfamilies. The FoxK subfamily is specifically absent from the silkworm, although it is present in other lepidopteran insects, including Danaus plexippus and Heliconius melpomene. Microarray data revealed that the Fox genes have distinct expression patterns in the tissues on day 3 of the 5th instar larva. A Gene Ontology analysis suggested that the Fox genes have roles in cellular components, molecular functions, and biological processes, except in pore complex biogenesis. An analysis of the selective pressure on the proteins indicated that most of the amino acid sites in the Fox proteins are undergoing strong purifying selection. Here, we summarize the general characteristics of the Fox genes in the silkworm, which should support further functional studies of the silkworm Fox proteins.

FoxP3 inhibits proliferation and induces apoptosis of gastric cancer cells by activating the apoptotic signaling pathway

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ma, Gui-Fen; Chen, Shi-Yao, E-mail: shiyao_chen@163.com; Endoscopy Center, Zhongshan Hospital, Fudan University, Shanghai

Highlights: Black-Right-Pointing-Pointer The article revealed FoxP3 gene function in gastric cancer firstly. Black-Right-Pointing-Pointer Present the novel roles of FoxP3 in inhibiting proliferation and promoting apoptosis in gastric cancer cells. Black-Right-Pointing-Pointer Overexpression of FoxP3 increased proapoptotic molecules and repressed antiapoptotic molecules. Black-Right-Pointing-Pointer Silencing of FoxP3 reduced the expression of proapoptotic genes, such as PARP, caspase-3 and caspase-9. Black-Right-Pointing-Pointer FoxP3 is sufficient for activating the apoptotic signaling pathway. -- Abstract: Forkhead Box Protein 3 (FoxP3) was identified as a key transcription factor to the occurring and function of the regulatory T cells (Tregs). However, limited evidence indicated its function in tumor cells.more » To elucidate the precise roles and underlying molecular mechanism of FoxP3 in gastric cancer (GC), we examined the expression of FoxP3 and the consequences of interfering with FoxP3 gene in human GC cell lines, AGS and MKN45, by multiple cellular and molecular approaches, such as immunofluorescence, gene transfection, CCK-8 assay, clone formation assay, TUNEL assay, Flow cytometry, immunoassay and quantities polymerase chain reaction (PCR). As a result, FoxP3 was expressed both in nucleus and cytoplasm of GC cells. Up-regulation of FoxP3 inhibited cell proliferation and promoted cell apoptosis. Overexpression of FoxP3 increased the protein and mRNA levels of proapoptotic molecules, such as poly ADP-ribose polymerase1 (PARP), caspase-3 and caspase-9, and repressed the expression of antiapoptotic molecules, such as cellular inhibitor of apoptosis-1 (c-IAP1) and the long isoform of B cell leukemia/lymphoma-2 (Bcl-2). Furthermore, silencing of FoxP3 by siRNA in GC cells reduced the expression of proapoptotic genes, such as PARP, caspase-3 and caspase-9. Collectively, our findings identify the novel roles of FoxP3 in inhibiting proliferation and inducing apoptosis in GC cells by regulating apoptotic signaling, which could be a promising therapeutic approach for gastric cancer.« less

Organ-specific gene expression: the bHLH protein Sage provides tissue specificity to Drosophila FoxA.

PubMed

Fox, Rebecca M; Vaishnavi, Aria; Maruyama, Rika; Andrew, Deborah J

2013-05-01

FoxA transcription factors play major roles in organ-specific gene expression, regulating, for example, glucagon expression in the pancreas, GLUT2 expression in the liver, and tyrosine hydroxylase expression in dopaminergic neurons. Organ-specific gene regulation by FoxA proteins is achieved through cooperative regulation with a broad array of transcription factors with more limited expression domains. Fork head (Fkh), the sole Drosophila FoxA family member, is required for the development of multiple distinct organs, yet little is known regarding how Fkh regulates tissue-specific gene expression. Here, we characterize Sage, a bHLH transcription factor expressed exclusively in the Drosophila salivary gland (SG). We show that Sage is required for late SG survival and normal tube morphology. We find that many Sage targets, identified by microarray analysis, encode SG-specific secreted cargo, transmembrane proteins, and the enzymes that modify these proteins. We show that both Sage and Fkh are required for the expression of Sage target genes, and that co-expression of Sage and Fkh is sufficient to drive target gene expression in multiple cell types. Sage and Fkh drive expression of the bZip transcription factor Senseless (Sens), which boosts expression of Sage-Fkh targets, and Sage, Fkh and Sens colocalize on SG chromosomes. Importantly, expression of Sage-Fkh target genes appears to simply add to the tissue-specific gene expression programs already established in other cell types, and Sage and Fkh cannot alter the fate of most embryonic cell types even when expressed early and continuously.

Organ-specific gene expression: the bHLH protein Sage provides tissue specificity to Drosophila FoxA

PubMed Central

Fox, Rebecca M.; Vaishnavi, Aria; Maruyama, Rika; Andrew, Deborah J.

2013-01-01

FoxA transcription factors play major roles in organ-specific gene expression, regulating, for example, glucagon expression in the pancreas, GLUT2 expression in the liver, and tyrosine hydroxylase expression in dopaminergic neurons. Organ-specific gene regulation by FoxA proteins is achieved through cooperative regulation with a broad array of transcription factors with more limited expression domains. Fork head (Fkh), the sole Drosophila FoxA family member, is required for the development of multiple distinct organs, yet little is known regarding how Fkh regulates tissue-specific gene expression. Here, we characterize Sage, a bHLH transcription factor expressed exclusively in the Drosophila salivary gland (SG). We show that Sage is required for late SG survival and normal tube morphology. We find that many Sage targets, identified by microarray analysis, encode SG-specific secreted cargo, transmembrane proteins, and the enzymes that modify these proteins. We show that both Sage and Fkh are required for the expression of Sage target genes, and that co-expression of Sage and Fkh is sufficient to drive target gene expression in multiple cell types. Sage and Fkh drive expression of the bZip transcription factor Senseless (Sens), which boosts expression of Sage-Fkh targets, and Sage, Fkh and Sens colocalize on SG chromosomes. Importantly, expression of Sage-Fkh target genes appears to simply add to the tissue-specific gene expression programs already established in other cell types, and Sage and Fkh cannot alter the fate of most embryonic cell types even when expressed early and continuously. PMID:23578928

Expression analysis of the speech-related genes FoxP1 and FoxP2 and their relation to singing behavior in two songbird species.

PubMed

Chen, Qianqian; Heston, Jonathan B; Burkett, Zachary D; White, Stephanie A

2013-10-01

Humans and songbirds are among the rare animal groups that exhibit socially learned vocalizations: speech and song, respectively. These vocal-learning capacities share a reliance on audition and cortico-basal ganglia circuitry, as well as neurogenetic mechanisms. Notably, the transcription factors Forkhead box proteins 1 and 2 (FoxP1, FoxP2) exhibit similar expression patterns in the cortex and basal ganglia of humans and the zebra finch species of songbird, among other brain regions. Mutations in either gene are associated with language disorders in humans. Experimental knock-down of FoxP2 in the basal ganglia song control region Area X during song development leads to imprecise copying of tutor songs. Moreover, FoxP2 levels decrease naturally within Area X when zebra finches sing. Here, we examined neural expression patterns of FoxP1 and FoxP2 mRNA in adult Bengalese finches, a songbird species whose songs exhibit greater sequence complexity and increased reliance on audition for maintaining their quality. We found that FoxP1 and FoxP2 expression in Bengalese finches is similar to that in zebra finches, including strong mRNA signals for both factors in multiple song control nuclei and enhancement of FoxP1 in these regions relative to surrounding brain tissue. As with zebra finches, when Bengalese finches sing, FoxP2 is behaviorally downregulated within basal ganglia Area X over a similar time course, and expression negatively correlates with the amount of singing. This study confirms that in multiple songbird species, FoxP1 expression highlights song control regions, and regulation of FoxP2 is associated with motor control of song.

Expression analysis of the speech-related genes FoxP1 and FoxP2 and their relation to singing behavior in two songbird species

PubMed Central

Chen, Qianqian; Heston, Jonathan B.; Burkett, Zachary D.; White, Stephanie A.

2013-01-01

SUMMARY Humans and songbirds are among the rare animal groups that exhibit socially learned vocalizations: speech and song, respectively. These vocal-learning capacities share a reliance on audition and cortico-basal ganglia circuitry, as well as neurogenetic mechanisms. Notably, the transcription factors Forkhead box proteins 1 and 2 (FoxP1, FoxP2) exhibit similar expression patterns in the cortex and basal ganglia of humans and the zebra finch species of songbird, among other brain regions. Mutations in either gene are associated with language disorders in humans. Experimental knock-down of FoxP2 in the basal ganglia song control region Area X during song development leads to imprecise copying of tutor songs. Moreover, FoxP2 levels decrease naturally within Area X when zebra finches sing. Here, we examined neural expression patterns of FoxP1 and FoxP2 mRNA in adult Bengalese finches, a songbird species whose songs exhibit greater sequence complexity and increased reliance on audition for maintaining their quality. We found that FoxP1 and FoxP2 expression in Bengalese finches is similar to that in zebra finches, including strong mRNA signals for both factors in multiple song control nuclei and enhancement of FoxP1 in these regions relative to surrounding brain tissue. As with zebra finches, when Bengalese finches sing, FoxP2 is behaviorally downregulated within basal ganglia Area X over a similar time course, and expression negatively correlates with the amount of singing. This study confirms that in multiple songbird species, FoxP1 expression highlights song control regions, and regulation of FoxP2 is associated with motor control of song. PMID:24006346

Circadian regulation of intestinal lipid absorption by apolipoprotein AIV involves forkhead transcription factors A2 and O1 and microsomal triglyceride transfer protein.

PubMed

Pan, Xiaoyue; Munshi, Mohamed Khalid; Iqbal, Jahangir; Queiroz, Joyce; Sirwi, Alaa Ahmed; Shah, Shrenik; Younus, Abdullah; Hussain, M Mahmood

2013-07-12

We have shown previously that Clock, microsomal triglyceride transfer protein (MTP), and nocturnin are involved in the circadian regulation of intestinal lipid absorption. Here, we clarified the role of apolipoprotein AIV (apoAIV) in the diurnal regulation of plasma lipids and intestinal lipid absorption in mice. Plasma triglyceride in apoAIV(-/-) mice showed diurnal variations similar to apoAIV(+/+) mice; however, the increases in plasma triglyceride at night were significantly lower in these mice. ApoAIV(-/-) mice absorbed fewer lipids at night and showed blunted response to daytime feeding. To explain reasons for these lower responses, we measured MTP expression; intestinal MTP was low at night, and its induction after food entrainment was less in apoAIV(-/-) mice. Conversely, apoAIV overexpression increased MTP mRNA in hepatoma cells, indicating transcriptional regulation. Mechanistic studies revealed that sequences between -204/-775 bp in the MTP promoter respond to apoAIV and that apoAIV enhances expression of FoxA2 and FoxO1 transcription factors and their binding to the identified cis elements in the MTP promoter at night. Knockdown of FoxA2 and FoxO1 abolished apoAIV-mediated MTP induction. Similarly, knockdown of apoAIV in differentiated Caco-2 cells reduced MTP, FoxA2, and FoxO1 mRNA levels, cellular MTP activity, and media apoB. Moreover, FoxA2 and FoxO1 expression showed diurnal variations, and their expression was significantly lower in apoAIV(-/-) mice. These data indicate that apoAIV modulates diurnal changes in lipid absorption by regulating forkhead transcription factors and MTP and that inhibition of apoAIV expression might reduce plasma lipids.

Chemotherapy resistance and metastasis-promoting effects of thyroid hormone in hepatocarcinoma cells are mediated by suppression of FoxO1 and Bim pathway

PubMed Central

Chi, Hsiang-Cheng; Chen, Shen-Liang; Cheng, Yi-Hung; Lin, Tzu-Kang; Tsai, Chung-Ying; Tsai, Ming-Ming; Lin, Yang-Hsiang; Huang, Ya-Hui; Lin, Kwang-Huei

2016-01-01

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related death worldwide, and systemic chemotherapy is the major treatment strategy for late-stage HCC patients. Poor prognosis following chemotherapy is the general outcome owing to recurrent resistance. Recent studies have suggested that in addition to cytotoxic effects on tumor cells, chemotherapy can induce an alternative cascade that supports tumor growth and metastasis. In the present investigation, we showed that thyroid hormone (TH), a potent hormone-mediating cellular differentiation and metabolism, acts as an antiapoptosis factor upon challenge of thyroid hormone receptor (TR)-expressing HCC cells with cancer therapy drugs, including cisplatin, doxorubicin and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). TH/TR signaling promoted chemotherapy resistance through negatively regulating the pro-apoptotic protein, Bim, resulting in doxorubicin-induced metastasis of chemotherapy-resistant HCC cells. Ectopic expression of Bim in hepatoma cells challenged with chemotherapeutic drugs abolished TH/TR-triggered apoptosis resistance and metastasis. Furthermore, Bim expression was directly transactivated by Forkhead box protein O1 (FoxO1), which was negatively regulated by TH/TR. TH/TR suppressed FoxO1 activity through both transcriptional downregulation and nuclear exclusion of FoxO1 triggered by Akt-mediated phosphorylation. Ectopic expression of the constitutively active FoxO1 mutant, FoxO1-AAA, but not FoxO1-wt, diminished the suppressive effect of TH/TR on Bim. Our findings collectively suggest that expression of Bim is mediated by FoxO1 and indirectly downregulated by TH/TR, leading to chemotherapy resistance and doxorubicin-promoted metastasis of hepatoma cells. PMID:27490929

FoxO and Stress Responses in the Cnidarian Hydra vulgaris

PubMed Central

Bridge, Diane; Theofiles, Alexander G.; Holler, Rebecca L.; Marcinkevicius, Emily; Steele, Robert E.; Martínez, Daniel E.

2010-01-01

Background In the face of changing environmental conditions, the mechanisms underlying stress responses in diverse organisms are of increasing interest. In vertebrates, Drosophila, and Caenorhabditis elegans, FoxO transcription factors mediate cellular responses to stress, including oxidative stress and dietary restriction. Although FoxO genes have been identified in early-arising animal lineages including sponges and cnidarians, little is known about their roles in these organisms. Methods/Principal Findings We have examined the regulation of FoxO activity in members of the well-studied cnidarian genus Hydra. We find that Hydra FoxO is expressed at high levels in cells of the interstitial lineage, a cell lineage that includes multipotent stem cells that give rise to neurons, stinging cells, secretory cells and gametes. Using transgenic Hydra that express a FoxO-GFP fusion protein in cells of the interstitial lineage, we have determined that heat shock causes localization of the fusion protein to the nucleus. Our results also provide evidence that, as in bilaterian animals, Hydra FoxO activity is regulated by both Akt and JNK kinases. Conclusions These findings imply that basic mechanisms of FoxO regulation arose before the evolution of bilaterians and raise the possibility that FoxO is involved in stress responses of other cnidarian species, including corals. PMID:20657733

FoxO and stress responses in the cnidarian Hydra vulgaris.

PubMed

Bridge, Diane; Theofiles, Alexander G; Holler, Rebecca L; Marcinkevicius, Emily; Steele, Robert E; Martínez, Daniel E

2010-07-21

In the face of changing environmental conditions, the mechanisms underlying stress responses in diverse organisms are of increasing interest. In vertebrates, Drosophila, and Caenorhabditis elegans, FoxO transcription factors mediate cellular responses to stress, including oxidative stress and dietary restriction. Although FoxO genes have been identified in early-arising animal lineages including sponges and cnidarians, little is known about their roles in these organisms. We have examined the regulation of FoxO activity in members of the well-studied cnidarian genus Hydra. We find that Hydra FoxO is expressed at high levels in cells of the interstitial lineage, a cell lineage that includes multipotent stem cells that give rise to neurons, stinging cells, secretory cells and gametes. Using transgenic Hydra that express a FoxO-GFP fusion protein in cells of the interstitial lineage, we have determined that heat shock causes localization of the fusion protein to the nucleus. Our results also provide evidence that, as in bilaterian animals, Hydra FoxO activity is regulated by both Akt and JNK kinases. These findings imply that basic mechanisms of FoxO regulation arose before the evolution of bilaterians and raise the possibility that FoxO is involved in stress responses of other cnidarian species, including corals.

Concurrent acetylation of FoxO1/3a and p53 due to sirtuins inhibition elicit Bim/PUMA mediated mitochondrial dysfunction and apoptosis in berberine-treated HepG2 cells.

PubMed

Shukla, Shatrunajay; Sharma, Ankita; Pandey, Vivek Kumar; Raisuddin, Sheikh; Kakkar, Poonam

2016-01-15

Post-translational modifications i.e. phosphorylation and acetylation are pivotal requirements for proper functioning of eukaryotic proteins. The current study aimed to decode the impact of acetylation/deacetylation of non-histone targets i.e. FoxO1/3a and p53 of sirtuins (NAD(+) dependent enzymes with lysine deacetylase activity) in berberine treated human hepatoma cells. Berberine (100 μM) inhibited sirtuins significantly (P<0.05) at transcriptional level as well as at translational level. Combination of nicotinamide (sirtuin inhibitor) with berberine potentiated sirtuins inhibition and increased the expression of FoxO1/3a and phosphorylation of p53 tumor suppressor protein. As sirtuins deacetylate non-histone targets including FoxO1/3a and p53, berberine increased the acetylation load of FoxO1/3a and p53 proteins. Acetylated FoxO and p53 proteins transcriptionally activate BH3-only proteins Bim and PUMA (3.89 and 3.87 fold respectively, P<0.001), which are known as direct activator of pro-apoptotic Bcl-2 family protein Bax that culminated into mitochondria mediated activation of apoptotic cascade. Bim/PUMA knock-down showed no changes in sirtuins' expression while cytotoxicity induced by berberine and nicotinamide was curtailed up to 28.3% (P<0.001) and it restored pro/anti apoptotic protein ratio in HepG2 cells. Sirtuins inhibition was accompanied by decline in NAD(+)/NADH ratio, ATP generation, enhanced ROS production and decreased mitochondrial membrane potential. TEM analysis confirmed mitochondrial deterioration and cell damage. SRT-1720 (1-10 μM), a SIRT-1 activator, when pre-treated with berberine (25 μM), reversed sirtuins expression comparable to control and significantly restored the cell viability (P<0.05). Thus, our findings suggest that berberine mediated sirtuins inhibition resulting into FoxO1/3a and p53 acetylation followed by BH3-only protein Bim/PUMA activation may in part be responsible for mitochondria-mediated apoptosis. Copyright © 2015 Elsevier Inc. All rights reserved.

Advanced Glycation End-Products affect transcription factors regulating insulin gene expression

DOE Office of Scientific and Technical Information (OSTI.GOV)

Puddu, A., E-mail: alep100@hotmail.com; Storace, D.; Odetti, P.

2010-04-23

Advanced Glycation End-Products (AGEs) are generated by the covalent interaction of reducing sugars with proteins, lipids or nucleic acids. AGEs are implicated in diabetic complications and pancreatic {beta}-cell dysfunction. We previously demonstrated that exposure of the pancreatic islet cell line HIT-T15 to high concentrations of AGEs leads to a significant decrease of insulin secretion and content. Insulin gene transcription is positively regulated by the beta cell specific transcription factor PDX-1 (Pancreatic and Duodenal Homeobox-1). On the contrary, the forkhead transcription factor FoxO1 inhibits PDX-1 gene transcription. Activity of FoxO1 is regulated by post-translational modifications: phosphorylation deactivates FoxO1, and acetylation preventsmore » FoxO1 ubiquitination. In this work we investigated whether AGEs affect expression and subcellular localization of PDX-1 and FoxO1. HIT-T15 cells were cultured for 5 days in presence of AGEs. Cells were then lysed and processed for subcellular fractionation. We determined intracellular insulin content, then we assessed the expression and subcellular localization of PDX-1, FoxO1, phosphoFoxO1 and acetylFoxO1. As expected intracellular insulin content was lower in HIT-T15 cells cultured with AGEs. The results showed that AGEs decreased expression and nuclear localization of PDX-1, reduced phosphorylation of FoxO1, and increased expression and acetylation of FoxO1. These results suggest that AGEs decrease insulin content unbalancing transcription factors regulating insulin gene expression.« less

Protein-Protein Interaction Among the FoxP Family Members and their Regulation of Two Target Genes, VLDLR and CNTNAP2 in the Zebra Finch Song System

PubMed Central

Mendoza, Ezequiel; Scharff, Constance

2017-01-01

The Forkhead transcription factor FOXP2 is implicated in speech perception and production. The avian homolog, FoxP21 contributes to song learning and production in birds. In human cell lines, transcriptional activity of FOXP2 requires homo-dimerization or dimerization with paralogs FOXP1 or FOXP4. Whether FoxP dimerization occurs in the brain is unknown. We recently showed that FoxP1, FoxP2 and FoxP4 (FoxP1/2/4) proteins are co-expressed in neurons of Area X, a song control region in zebra finches. We now report on dimer- and oligomerization of zebra finch FoxPs and how this affects transcription. In cell lines and in the brain we identify homo- and hetero-dimers, and an oligomer composed of FoxP1/2/4. We further show that FoxP1/2 but not FoxP4 bind to the regulatory region of the target gene Contactin-associated protein-like 2 (CNTNAP2). In addition, we demonstrate that FoxP1/4 bind to the regulatory region of very low density lipoprotein receptor (VLDLR), as has been shown for FoxP2 previously. Interestingly, FoxP1/2/4 individually or in combinations regulate the promoters for SV40, zebra finch VLDLR and CNTNAP2 differentially. These data exemplify the potential for complex transcriptional regulation of FoxP1/2/4, highlighting the need for future functional studies dissecting their differential regulation in the brain. PMID:28507505

Anaphase-Promoting Complex/Cyclosome-Cdh1-Mediated Proteolysis of the Forkhead Box M1 Transcription Factor Is Critical for Regulated Entry into S Phase▿

PubMed Central

Park, Hyun Jung; Costa, Robert H.; Lau, Lester F.; Tyner, Angela L.; Raychaudhuri, Pradip

2008-01-01

The forkhead box M1 (FoxM1) transcription factor is overexpressed in many cancers, and in mouse models it is required for tumor progression. FoxM1 activates expression of the cell cycle genes required for both S and M phase progression. Here we demonstrate that FoxM1 is degraded in late mitosis and early G1 phase by the anaphase-promoting complex/cyclosome (APC/C) E3 ubiquitin ligase. FoxM1 interacts with the APC/C complex and its adaptor, Cdh1. Expression of Cdh1 stimulated degradation of the FoxM1 protein, and depletion of Cdh1 resulted in stabilization of the FoxM1 protein in late mitosis and in early G1 phase of the cell cycle. Cdh1 has been implicated in regulating S phase entry. We show that codepletion of FoxM1 inhibits early S phase entry observed in Cdh1-depleted cells. The N-terminal region of FoxM1 contains both destruction box (D box) and KEN box sequences that are required for targeting by Cdh1. Mutation of either the D box sequence or the KEN box sequence stabilized FoxM1 and blocked Cdh1-induced proteolysis. Cells expressing a nondegradable form of FoxM1 entered S phase rapidly following release from M phase arrest. Together, our observations show that FoxM1 is one of the targets of Cdh1 in late M or early G1 phase and that its proteolysis is important for regulated entry into S phase. PMID:18573889

Anaphase-promoting complex/cyclosome-CDH1-mediated proteolysis of the forkhead box M1 transcription factor is critical for regulated entry into S phase.

PubMed

Park, Hyun Jung; Costa, Robert H; Lau, Lester F; Tyner, Angela L; Raychaudhuri, Pradip

2008-09-01

The forkhead box M1 (FoxM1) transcription factor is overexpressed in many cancers, and in mouse models it is required for tumor progression. FoxM1 activates expression of the cell cycle genes required for both S and M phase progression. Here we demonstrate that FoxM1 is degraded in late mitosis and early G(1) phase by the anaphase-promoting complex/cyclosome (APC/C) E3 ubiquitin ligase. FoxM1 interacts with the APC/C complex and its adaptor, Cdh1. Expression of Cdh1 stimulated degradation of the FoxM1 protein, and depletion of Cdh1 resulted in stabilization of the FoxM1 protein in late mitosis and in early G(1) phase of the cell cycle. Cdh1 has been implicated in regulating S phase entry. We show that codepletion of FoxM1 inhibits early S phase entry observed in Cdh1-depleted cells. The N-terminal region of FoxM1 contains both destruction box (D box) and KEN box sequences that are required for targeting by Cdh1. Mutation of either the D box sequence or the KEN box sequence stabilized FoxM1 and blocked Cdh1-induced proteolysis. Cells expressing a nondegradable form of FoxM1 entered S phase rapidly following release from M phase arrest. Together, our observations show that FoxM1 is one of the targets of Cdh1 in late M or early G(1) phase and that its proteolysis is important for regulated entry into S phase.

The control of foxN2/3 expression in sea urchin embryos and its function in the skeletogenic gene regulatory network.

PubMed

Rho, Ho Kyung; McClay, David R

2011-03-01

Early development requires well-organized temporal and spatial regulation of transcription factors that are assembled into gene regulatory networks (GRNs). In the sea urchin, an endomesoderm GRN model explains much of the specification in the endoderm and mesoderm prior to gastrulation, yet some GRN connections remain incomplete. Here, we characterize FoxN2/3 in the primary mesenchyme cell (PMC) GRN state. Expression of foxN2/3 mRNA begins in micromeres at the hatched blastula stage and then is lost from micromeres at the mesenchyme blastula stage. foxN2/3 expression then shifts to the non-skeletogenic mesoderm and, later, to the endoderm. Here, we show that Pmar1, Ets1 and Tbr are necessary for activation of foxN2/3 in micromeres. The later endomesoderm expression of foxN2/3 is independent of the earlier expression of foxN2/3 in micromeres and is independent of signals from PMCs. FoxN2/3 is necessary for several steps in the formation of the larval skeleton. Early expression of genes for the skeletal matrix is dependent on FoxN2/3, but only until the mesenchyme blastula stage as foxN2/3 mRNA disappears from PMCs at that time and we assume that the protein is not abnormally long-lived. Knockdown of FoxN2/3 inhibits normal PMC ingression and foxN2/3 morphant PMCs do not organize in the blastocoel and fail to join the PMC syncytium. In addition, without FoxN2/3, the PMCs fail to repress the transfating of other mesodermal cells into the skeletogenic lineage. Thus, FoxN2/3 is necessary for normal ingression, for expression of several skeletal matrix genes, for preventing transfating and for fusion of the PMC syncytium.

Concurrent acetylation of FoxO1/3a and p53 due to sirtuins inhibition elicit Bim/PUMA mediated mitochondrial dysfunction and apoptosis in berberine-treated HepG2 cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shukla, Shatrunajay; Department of Medical Elementology and Toxicology, Jamia Hamdard; Sharma, Ankita

Post-translational modifications i.e. phosphorylation and acetylation are pivotal requirements for proper functioning of eukaryotic proteins. The current study aimed to decode the impact of acetylation/deacetylation of non-histone targets i.e. FoxO1/3a and p53 of sirtuins (NAD{sup +} dependent enzymes with lysine deacetylase activity) in berberine treated human hepatoma cells. Berberine (100 μM) inhibited sirtuins significantly (P < 0.05) at transcriptional level as well as at translational level. Combination of nicotinamide (sirtuin inhibitor) with berberine potentiated sirtuins inhibition and increased the expression of FoxO1/3a and phosphorylation of p53 tumor suppressor protein. As sirtuins deacetylate non-histone targets including FoxO1/3a and p53, berberine increasedmore » the acetylation load of FoxO1/3a and p53 proteins. Acetylated FoxO and p53 proteins transcriptionally activate BH3-only proteins Bim and PUMA (3.89 and 3.87 fold respectively, P<0.001), which are known as direct activator of pro-apoptotic Bcl-2 family protein Bax that culminated into mitochondria mediated activation of apoptotic cascade. Bim/PUMA knock-down showed no changes in sirtuins' expression while cytotoxicity induced by berberine and nicotinamide was curtailed up to 28.3% (P < 0.001) and it restored pro/anti apoptotic protein ratio in HepG2 cells. Sirtuins inhibition was accompanied by decline in NAD{sup +}/NADH ratio, ATP generation, enhanced ROS production and decreased mitochondrial membrane potential. TEM analysis confirmed mitochondrial deterioration and cell damage. SRT-1720 (1–10 μM), a SIRT-1 activator, when pre-treated with berberine (25 μM), reversed sirtuins expression comparable to control and significantly restored the cell viability (P < 0.05). Thus, our findings suggest that berberine mediated sirtuins inhibition resulting into FoxO1/3a and p53 acetylation followed by BH3-only protein Bim/PUMA activation may in part be responsible for mitochondria-mediated apoptosis. - Highlights: • Berberine inhibits sirtuins at transcriptional as well as at translational level. • Sirtuins inhibition leads to acetylation of non-histone proteins, FoxO1/3a and p53. • Acetylated FoxO and p53 transcriptionally upregulate BH3-only proteins Bim and PUMA respectively. • BH3-only proteins trigger mitochondrial dysfunction culminating into apoptosis. • SRT-1720 (SIRT-1 activator) partially restores Bax/Bcl-2 ratio and reduces berberine induced cytotoxicity in HepG2 cells.« less

Inhibition of FoxO transcriptional activity prevents muscle fiber atrophy during cachexia and induces hypertrophy

PubMed Central

Reed, Sarah A.; Sandesara, Pooja B.; Senf, Sarah M.; Judge, Andrew R.

2012-01-01

Cachexia is characterized by inexorable muscle wasting that significantly affects patient prognosis and increases mortality. Therefore, understanding the molecular basis of this muscle wasting is of significant importance. Recent work showed that components of the forkhead box O (FoxO) pathway are increased in skeletal muscle during cachexia. In the current study, we tested the physiological significance of FoxO activation in the progression of muscle atrophy associated with cachexia. FoxO-DNA binding dependent transcription was blocked in the muscles of mice through injection of a dominant negative (DN) FoxO expression plasmid prior to inoculation with Lewis lung carcinoma cells or the induction of sepsis. Expression of DN FoxO inhibited the increased mRNA levels of atrogin-1, MuRF1, cathepsin L, and/or Bnip3 and inhibited muscle fiber atrophy during cancer cachexia and sepsis. Interestingly, during control conditions, expression of DN FoxO decreased myostatin expression, increased MyoD expression and satellite cell proliferation, and induced fiber hypertrophy, which required de novo protein synthesis. Collectively, these data show that FoxO-DNA binding-dependent transcription is necessary for normal muscle fiber atrophy during cancer cachexia and sepsis, and further suggest that basal levels of FoxO play an important role during normal conditions to depress satellite cell activation and limit muscle growth.—Reed, S. A., Sandesara, P. B., Senf, S. F., Judge, A. R. Inhibition of FoxO transcriptional activity prevents muscle fiber atrophy during cachexia and induces hypertrophy. PMID:22102632

Lack of the central nervous system- and neural crest-expressed forkhead gene Foxs1 affects motor function and body weight.

PubMed

Heglind, Mikael; Cederberg, Anna; Aquino, Jorge; Lucas, Guilherme; Ernfors, Patrik; Enerbäck, Sven

2005-07-01

To gain insight into the expression pattern and functional importance of the forkhead transcription factor Foxs1, we constructed a Foxs1-beta-galactosidase reporter gene "knock-in" (Foxs1beta-gal/beta-gal) mouse, in which the wild-type (wt) Foxs1 allele has been inactivated and replaced by a beta-galactosidase reporter gene. Staining for beta-galactosidase activity reveals an expression pattern encompassing neural crest-derived cells, e.g., cranial and dorsal root ganglia as well as several other cell populations in the central nervous system (CNS), most prominently the internal granule layer of cerebellum. Other sites of expression include the lachrymal gland, outer nuclear layer of retina, enteric ganglion neurons, and a subset of thalamic and hypothalamic nuclei. In the CNS, blood vessel-associated smooth muscle cells and pericytes stain positive for Foxs1. Foxs1beta-gal/beta-gal mice perform significantly better (P < 0.01) on a rotating rod than do wt littermates. We have also noted a lower body weight gain (P < 0.05) in Foxs1beta-gal/lbeta-gal males on a high-fat diet, and we speculate that dorsomedial hypothalamic neurons, expressing Foxs1, could play a role in regulating body weight via regulation of sympathetic outflow. In support of this, we observed increased levels of uncoupling protein 1 mRNA in Foxs1beta-gal/beta-gal mice. This points toward a role for Foxs1 in the integration and processing of neuronal signals of importance for energy turnover and motor function.

Posttranslational modulation of FoxO1 contributes to cardiac remodeling in post-ischemic heart failure.

PubMed

Kappel, Ben Arpad; Stöhr, Robert; De Angelis, Lorenzo; Mavilio, Maria; Menghini, Rossella; Federici, Massimo

2016-06-01

Forkhead box protein O1 (FoxO1) plays a key role in energy homeostasis, stress response and autophagy and is dysregulated in diabetes and ischemia. We investigated cardiac FoxO1 expression and posttranstranslational modifications after myocardial infarction (MI) and further tested if active posttranstranslational modulation of FoxO1 can alter cardiac remodeling in postischemic heart failure. Non-diabetic and diabetic C57BL/6 mice were subjected to MI by ligation of left anterior descending artery. In selected experiments we combined this model with intramyocardial injection of adenovirus expressing different isoforms of FoxO1. We used Millar catheter, histology, Western blot and metabolomics for further analyses. We show that after MI total cardiac FoxO1 is downregulated and partly recovers after 7 days. This downregulation is accompanied by fundamental posttranslational modifications of FoxO1, particularly acetylation. Adenovirus experiments revealed smaller infarction size and improved heart function in mice expressing a constitutively deacetylated variant of FoxO1 compared to a wild type variant of FoxO1 in both non-diabetic (MI size: -13.4 ± 3.5%; LVDP: +29.1 ± 9.4  mmHg; p < 0.05) and diabetic mice (MI size: -17.6 ± 3.7%; LVDP: +10.9 ± 3.6  mmHg; p < 0.05). Metabolomics analyses showed alterations in metabolites connected to muscle breakdown, collagen/elastin and energy metabolism between the two groups. First, our results demonstrate that myocardial ischemia is associated with downregulation and posttranslational modification of cardiac FoxO1. Second, we show in a mouse model of postischemic heart failure that posttranslational modulation of FoxO1 alters heart function involving collagen and protein metabolism. Therefore, posttranslational modifications of FoxO1 could be an option to target remodeling processes in postischemic heart failure. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Effects of sex and seasonality on the song control system and FoxP2 protein expression in black-capped chickadees (Poecile atricapillus).

PubMed

Phillmore, Leslie S; MacGillivray, Heather L; Wilson, K Ryan; Martin, Stephanie

2015-02-01

Plasticity in behavior is mirrored by corresponding plasticity in the brain in many songbird species. In some species, song system nuclei (Phillmore et al. [2006]: J Neurobiol 66:1002-1010) are larger in birds in breeding condition than birds in nonbreeding condition, possibly due to increased vocal output in spring. FOXP2, a transcription factor associated with language expression and comprehension in humans and song learning in songbirds, also shows plasticity. FoxP2 expression in songbird Area X, a region important for sensorimotor integration, is related to developmental and adult vocal plasticity (Teramitsu et al. [2010]: J Neurosci 24:3152-3163, Chen et al. [2013], J Exp Biol 216:3682-3692). In this study, we examined whether sex and breeding condition affects both song control system volume (HVC, X) and FoxP2 protein expression in black-capped chickadees (Poecile atricapillus). HVC volume was larger in males in breeding condition than males in nonbreeding condition, but there were no sex differences. In contrast, Area X volume was larger in males than females, regardless of breeding condition, likely reflecting that male and female chickadees produce learned chick-a-dee calls year round, but output of the learned song increases in breeding males. FoxP2 protein levels did not differ between sexes or breeding condition when calculated as a ratio of labeled cells in Area X to labeled cells in the surrounding striato-pallium, however, absolute density of FoxP2 in both regions was higher in males than in females. This may indicate that chickadees maintain a level of FoxP2 necessary for plasticity year-round, but males have greater potential for plasticity compared to females. © 2014 Wiley Periodicals, Inc.

Alcohol alters hepatic FoxO1, p53, and mitochondrial SIRT5 deacetylation function

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lieber, Charles S.; Department of Medicine, Mount Sinai School of Medicine, New York, NY 10029; Leo, Maria Anna

2008-08-22

Chronic alcohol consumption affects the gene expression of a NAD-dependent deacetylase Sirtuis 1 (SIRT1) and the peroxisome proliferator-activated receptor-{gamma} coactivator1{alpha} (PGC-1{alpha}). Our aim was to verify that it also alters the forkhead (FoxO1) and p53 transcription factor proteins, critical in the hepatic response to oxidative stress and regulated by SIRT1 through its deacetylating capacity. Accordingly, rats were pair-fed the Lieber-DeCarli alcohol-containing liquid diets for 28 days. Alcohol increased hepatic mRNA expression of FoxO1 (p = 0.003) and p53 (p = 0.001) while corresponding protein levels remained unchanged. However phospho-FoxO1 and phospho-Akt (protein kinase) were both decreased by alcohol consumption (pmore » = 0.04 and p = 0.02, respectively) while hepatic p53 was found hyperacetylated (p = 0.017). Furthermore, mitochondrial SIRT5 was reduced (p = 0.0025), and PGC-1{alpha} hyperacetylated (p = 0.027), establishing their role in protein modification. Thus, alcohol consumption disrupts nuclear-mitochondrial interactions by post-translation protein modifications, which contribute to alteration of mitochondrial biogenesis through the newly discovered reduction of SIRT5.« less

AMP-activated protein kinase couples 3-bromopyruvate-induced energy depletion to apoptosis via activation of FoxO3a and upregulation of proapoptotic Bcl-2 proteins.

PubMed

Bodur, Cagri; Karakas, Bahriye; Timucin, Ahmet Can; Tezil, Tugsan; Basaga, Huveyda

2016-11-01

Most tumors primarily rely on glycolysis rather than mitochondrial respiration for ATP production. This phenomenon, also known as Warburg effect, renders tumors more sensitive to glycolytic disturbances compared to normal cells. 3-bromopyruvate is a potent inhibitor of glycolysis that shows promise as an anticancer drug candidate. Although investigations revealed that 3-BP triggers apoptosis through ATP depletion and subsequent AMPK activation, the underlying molecular mechanisms coupling AMPK to apoptosis are poorly understood. We showed that 3-BP leads to a rapid ATP depletion which was followed by growth inhibition and Bax-dependent apoptosis in HCT116 cells. Apoptosis was accompanied with activation of caspase-9 and -3 while pretreatment with a general caspase inhibitor attenuated cell death. AMPK, p38, JNK, and Akt were phosphorylated immediately upon treatment. Pharmacological inhibition and silencing of AMPK largely inhibited 3-BP-induced apoptosis and reversed phosphorylation of JNK. Transcriptional activity of FoxO3a was dramatically increased subsequent to AMPK-mediated phosphorylation of FoxO3a at Ser413. Cell death analysis of cells transiently transfected with wt or AMPK-phosphorylation-deficient FoxO3 expression plasmids verified the contributory role of AMPK-FoxO3a axis in 3-BP-induced apoptosis. In addition, expression of proapoptotic Bcl-2 proteins Bim and Bax were upregulated in an AMPK-dependent manner. Bim was transcriptionally activated in association with FoxO3a activity, while Bax upregulation was abolished in p53-null cells. Together, these data suggest that AMPK couples 3-BP-induced metabolic disruption to intrinsic apoptosis via modulation of FoxO3a-Bim axis and Bax expression. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

FoxP2 regulates neurogenesis during embryonic cortical development.

PubMed

Tsui, David; Vessey, John P; Tomita, Hideaki; Kaplan, David R; Miller, Freda D

2013-01-02

The transcription factor FoxP2 has been associated with the development of human speech but the underlying cellular function of FoxP2 is still unclear. Here we provide evidence that FoxP2 regulates genesis of some intermediate progenitors and neurons in the mammalian cortex, one of the key centers for human speech. Specifically, knockdown of FoxP2 in embryonic cortical precursors inhibits neurogenesis, at least in part by inhibiting the transition from radial glial precursors to neurogenic intermediate progenitors. Moreover, overexpression of human, but not mouse, FoxP2 enhances the genesis of intermediate progenitors and neurons. In contrast, expression of a human FoxP2 mutant that causes vocalization deficits decreases neurogenesis, suggesting that in the murine system human FoxP2 acts as a gain-of-function protein, while a human FoxP2 mutant acts as a dominant-inhibitory protein. These results support the idea that FoxP2 regulates the transition from neural precursors to transit-amplifying progenitors and ultimately neurons, and shed light upon the molecular changes that might contribute to evolution of the mammalian cortex.

AmphiFoxE4, an amphioxus winged helix/forkhead gene encoding a protein closely related to vertebrate thyroid transcription factor-2: expression during pharyngeal development

NASA Technical Reports Server (NTRS)

Yu, Jr-Kai; Holland, Linda Z.; Jamrich, Milan; Blitz, Ira L.; Hollan, Nicholas D.

2002-01-01

The full-length sequence and developmental expression of amphioxus AmphiFoxE4 are described. Transcripts of the gene are first detected in the pharyngeal endoderm, where the club-shaped gland is forming and subsequently in the definitive gland itself. AmphiFoxE4 is closely related to vertebrate genes encoding the thyroid-specific transcription factor-2 (TTF2), which plays an early developmental role in the morphogenesis of the thyroid gland and a later role in hormone-mediated control of thyroid function. In amphioxus, AmphiFoxE4 expression is not thyroid specific because the club-shaped gland, the only structure expressing the gene, is not homologous to the vertebrate thyroid; instead, the thyroid homologue of amphioxus is a specialized region of the pharyngeal endoderm called the endostyle. We propose that (a) the pharynx of an amphioxus-like ancestor of the vertebrates included a club-shaped gland that expressed FoxE4 as well as an endostyle that did not, and (b) the club-shaped gland soon disappeared in the vertebrate line of descent but (c) not before there was a homeogenetic transfer of FoxE4 expression from the club-shaped gland to the nearby endostyle. Such a transfer could have provided part of the genetic program enabling the endostyle to separate from the pharyngeal endoderm and migrate away as the rudiment of the thyroid gland.

Carbocysteine counteracts the effects of cigarette smoke on cell growth and on the SIRT1/FoxO3 axis in bronchial epithelial cells.

PubMed

Pace, E; Di Vincenzo, S; Ferraro, M; Bruno, A; Dino, P; Bonsignore, M R; Battaglia, S; Saibene, F; Lanata, L; Gjomarkaj, M

2016-08-01

Cigarette smoke may accelerate cellular senescence by increasing oxidative stress. Altered proliferation and altered expression of anti-aging factors, including SIRT1 and FoxO3, characterise cellular senescence. The effects of carbocysteine on the SIRT1/FoxO3 axis and on downstream molecular mechanisms in human bronchial epithelial cells exposed to cigarette smoke are largely unknown. Aim of this study was to explore whether carbocysteine modulated SIRT1/FoxO3 axis, and downstream molecular mechanisms associated to cellular senescence, in a bronchial epithelial cell line (16-HBE) exposed to cigarette smoke. 16HBE cells were stimulated with/without cigarette smoke extracts (CSE) and carbocysteine. Flow cytometry and clonogenic assay were used to assess cell proliferation; western blot analysis was used for assessing nuclear expression of SIRT1 and FoxO3. The nuclear co-localization of SIRT1 and FoxO3 was assessed by fluorescence microscopy. Beta galactosidase (a senescence marker) and SIRT1 activity were assessed by specific staining and colorimetric assays, respectively. ChiP Assay and flow cytometry were used for assessing survivin gene regulation and protein expression, respectively. CSE decreased cell proliferation, the nuclear expression of SIRT1 and FoxO3 and increased beta galactosidase staining. CSE, reduced SIRT1 activity and FoxO3 localization on survivin promoter thus increasing survivin expression. In CSE stimulated bronchial epithelial cells carbocysteine reverted these phenomena by increasing cell proliferation, and SIRT1 and FoxO3 nuclear expression, and by reducing beta galactosidase staining and survivin expression. The study shows for the first time that carbocysteine may revert some senescence processes induced by oxidative stress due to cigarette smoke exposure. Copyright © 2016 Elsevier Inc. All rights reserved.

The Human T-Cell Leukemia Virus Type 1 Oncoprotein Tax Controls Forkhead Box O4 Activity through Degradation by the Proteasome▿

PubMed Central

Oteiza, Alexandra; Mechti, Nadir

2011-01-01

Activation of the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway by the viral Tax oncoprotein plays a pivotal role in clonal expansion of human T-cell leukemia virus type 1 (HTLV-1)-infected cells. As the Forkhead box O (FoxO) tumor suppressors act as downstream effectors of PI3K/Akt, they represent good candidate targets whose dysregulation by Tax might be involved in HTLV-1-mediated activation and transformation of infected cells. In this report, we provide evidence showing that Tax induces a dose-dependent degradation of FoxO4 by the ubiquitin-proteasome pathway. Consistent with that, we demonstrate that Tax expression increases the interaction between FoxO4 and Mdm2 E3 ligase, leading to a strong FoxO4 polyubiquitination. These processes require the phosphorylation of FoxO4 by Akt, since a mutant of FoxO4 with mutations on its three Akt phosphorylation sites appears to be resistant to Tax-mediated degradation and ubiquitination. In addition, we show that Tax expression is associated with degradation and phosphorylation of endogenous FoxO4 in Jurkat T cells. Finally, we demonstrate that Tax represses FoxO4 transcriptional activity. Our study demonstrates that Tax can control FoxO4 protein stability and transcriptional activity and provides new insight into the subversion of cell signaling pathways during HTLV-1 infection. PMID:21525355

miR-9 and miR-140-5p target FoxP2 and are regulated as a function of the social context of singing behavior in zebra finches.

PubMed

Shi, Zhimin; Luo, Guanzheng; Fu, Lijuan; Fang, Zhide; Wang, XiuJie; Li, XiaoChing

2013-10-16

Mutations in the FOXP2 gene cause speech and language impairments, accompanied by structural and functional abnormalities in brain regions underlying speech-related sensory-motor processing, including the striatum and cerebellum. The sequence and expression patterns of FOXP2 are highly conserved among higher vertebrates. In the zebra finch brain, FoxP2 is expressed in Area X, a striatal nucleus required for vocal learning, and reduced FoxP2 expression impairs dendritic development and vocal learning. The FoxP2 gene encodes a transcription factor that controls the expression of many downstream genes. However, how FOXP2 gene expression is regulated is not clearly understood. miRNAs regulate gene expression post-transcriptionally by targeting the 3'-untranslated regions (UTRs) of mRNAs, leading to translational suppression or mRNA degradation. In this study, we identified miR-9 and miR-140-5p as potential regulators of the FoxP2 gene. We show that both miR-9 and miR-140-5p target specific sequences in the FoxP2 3'-UTR and downregulate FoxP2 protein and mRNA expression in vitro. We also show that the expression of miR-9 and miR-140-5p in Area X of the zebra finch brain is regulated during song development in juvenile zebra finches. We further show that in adult zebra finches the expression of miR-9 and miR-140-5p in Area X is regulated as a function of the social context of song behavior in males singing undirected songs. Our findings reveal a post-transcriptional mechanism that regulates FoxP2 expression and suggest that social vocal behavior can influence the basal ganglia circuit controlling vocal learning via a miRNA-FoxP2 gene regulatory network.

miR-9 and miR-140-5p Target FoxP2 and Are Regulated as a Function of the Social Context of Singing Behavior in Zebra Finches

PubMed Central

Shi, Zhimin; Luo, Guanzheng; Fu, Lijuan; Fang, Zhide; Wang, XiuJie

2013-01-01

Mutations in the FOXP2 gene cause speech and language impairments, accompanied by structural and functional abnormalities in brain regions underlying speech-related sensory-motor processing, including the striatum and cerebellum. The sequence and expression patterns of FOXP2 are highly conserved among higher vertebrates. In the zebra finch brain, FoxP2 is expressed in Area X, a striatal nucleus required for vocal learning, and reduced FoxP2 expression impairs dendritic development and vocal learning. The FoxP2 gene encodes a transcription factor that controls the expression of many downstream genes. However, how FOXP2 gene expression is regulated is not clearly understood. miRNAs regulate gene expression post-transcriptionally by targeting the 3′-untranslated regions (UTRs) of mRNAs, leading to translational suppression or mRNA degradation. In this study, we identified miR-9 and miR-140-5p as potential regulators of the FoxP2 gene. We show that both miR-9 and miR-140-5p target specific sequences in the FoxP2 3′-UTR and downregulate FoxP2 protein and mRNA expression in vitro. We also show that the expression of miR-9 and miR-140-5p in Area X of the zebra finch brain is regulated during song development in juvenile zebra finches. We further show that in adult zebra finches the expression of miR-9 and miR-140-5p in Area X is regulated as a function of the social context of song behavior in males singing undirected songs. Our findings reveal a post-transcriptional mechanism that regulates FoxP2 expression and suggest that social vocal behavior can influence the basal ganglia circuit controlling vocal learning via a miRNA-FoxP2 gene regulatory network. PMID:24133256

Nodal enhances the activity of FoxO3a and its synergistic interaction with Smads to regulate cyclin G2 transcription in ovarian cancer cells.

PubMed

Fu, G; Peng, C

2011-09-15

Nodal, a member of the transforming growth factor-β superfamily, has been recently shown to suppress cell proliferation and to stimulate the expression of cyclin G2 (CCNG2) in human epithelial ovarian cancer cells. However, the precise mechanisms underlying these events are not fully understood. In this study, we investigated the transcriptional regulation of CCNG2 by the Nodal signaling pathway. In ovarian cancer cells, overexpression of Nodal or its receptors, activin receptor-like kinase 7 (ALK7) or ALK4, resulted in an increase in the CCNG2 promoter activity. Several putative Forkhead box class O (FoxO)3a-binding sites are present in the human CCNG2 promoter and overexpression of FoxO3a enhanced the CCNG2 promoter activity. The functional FoxO3a-binding element (FBE) was mapped to a proximal region located between -398 and -380 bp (FBE1) through deletion and mutation analyses, as well as chromatin immunoprecipitation (IP) assay. Interestingly, mutation of the FBE1 not only abolished the effect of FoxO3a, but also blocked Nodal-induced CCNG2 transcription. Nodal stimulated FoxO3a mRNA and protein expression through the canonical Smad pathway and suppressed FoxO3a inactivation by inhibiting AKT activity. Silencing of FoxO3a using small interfering RNA significantly reduced the effect of Nodal on the CCNG2 promoter activity. On the other hand, overexpression of Smad2 and Smad3 enhanced the FoxO3a-induced CCNG2 promoter activity whereas knockdown of Smad4 blocked the activity of FoxO3a. Furthermore, IP assays revealed that FoxO3a formed complexes with Smad proteins and that Nodal enhanced the binding of FoxO3a to the CCNG2 promoter. Finally, silencing of FoxO3a reversed the inhibitory effect of Nodal on cell proliferation. Taken together, these findings demonstrated that Nodal signaling promotes CCNG2 transcription by upregulating FoxO3a expression, inhibiting FoxO3a phosphorylation and enhancing its synergistic interaction with Smads. These results also suggest that FoxO3a is an important mediator of Nodal signaling in ovarian cancer cells.

C. elegans EAK-3 inhibits dauer arrest via nonautonomous regulation of nuclear DAF-16/FoxO activity

PubMed Central

Zhang, Yanmei; Xu, Jinling; Puscau, Cristina; Kim, Yongsoon; Wang, Xi; Alam, Hena; Hu, Patrick J.

2008-01-01

SUMMARY Insulin regulates development, metabolism, and lifespan via a conserved PI3K/Akt pathway that promotes cytoplasmic sequestration of FoxO transcription factors. The regulation of nuclear FoxO is poorly understood. In the nematode Caenorhabditis elegans, insulin-like signaling functions in larvae to inhibit dauer arrest and acts during adulthood to regulate lifespan. In a screen for genes that modulate C. elegans insulin-like signaling, we identified eak-3, which encodes a novel protein that is specifically expressed in the two endocrine XXX cells. The dauer arrest phenotype of eak-3 mutants is fully suppressed by mutations in daf-16/FoxO, which encodes the major target of C. elegans insulin-like signaling, and daf-12, which encodes a nuclear receptor regulated by steroid hormones known as dafachronic acids. eak-3 mutation does not affect DAF-16/FoxO subcellular localization but enhances expression of the direct DAF-16/FoxO target sod-3 in a daf-16/FoxO- and daf-12-dependent manner. eak-3 mutants have normal lifespans, suggesting that EAK-3 decouples insulin-like regulation of development and longevity. We propose that EAK-3 activity in the XXX cells promotes the synthesis and/or secretion of a hormone that acts in parallel to AKT-1 to inhibit the expression of DAF-16/FoxO target genes. Similar hormonal pathways may regulate FoxO target gene expression in mammals. PMID:18241854

Cross-talk among HMGA1 and FoxO1 in control of nuclear insulin signaling.

PubMed

Chiefari, Eusebio; Arcidiacono, Biagio; Palmieri, Camillo; Corigliano, Domenica Maria; Morittu, Valeria Maria; Britti, Domenico; Armoni, Michal; Foti, Daniela Patrizia; Brunetti, Antonio

2018-06-04

As a mediator of insulin-regulated gene expression, the FoxO1 transcription factor represents a master regulator of liver glucose metabolism. We previously reported that the high-mobility group AT-hook 1 (HMGA1) protein, a molecular switch for the insulin receptor gene, functions also as a downstream target of the insulin receptor signaling pathway, representing a critical nuclear mediator of insulin function. Here, we investigated whether a functional relationship existed between FoxO1 and HMGA1, which might help explain insulin-mediated gene transcription in the liver. To this end, as a model study, we investigated the canonical FoxO1-HMGA1-responsive IGFBP1 gene, whose hepatic expression is regulated by insulin. By using a conventional GST-pull down assay combined with co-immunoprecipitation and Fluorescence Resonance Energy Transfer (FRET) analyses, we provide evidence of a physical interaction between FoxO1 and HMGA1. Further investigation with chromatin immunoprecipitation, confocal microscopy, and Fluorescence Recovery After Photobleaching (FRAP) technology indicated a functional significance of this interaction, in both basal and insulin-stimulated states, providing evidence that, by modulating FoxO1 transactivation, HMGA1 is essential for FoxO1-induced IGFBP1 gene expression, and thereby a critical modulator of insulin-mediated FoxO1 regulation in the liver. Collectively, our findings highlight a novel FoxO1/HMGA1-mediated mechanism by which insulin may regulate gene expression and metabolism.

FOX-2 Dependent Splicing of Ataxin-2 Transcript Is Affected by Ataxin-1 Overexpression

PubMed Central

Welzel, Franziska; Kaehler, Christian; Isau, Melanie; Hallen, Linda; Lehrach, Hans; Krobitsch, Sylvia

2012-01-01

Alternative splicing is a fundamental posttranscriptional mechanism for controlling gene expression, and splicing defects have been linked to various human disorders. The splicing factor FOX-2 is part of a main protein interaction hub in a network related to human inherited ataxias, however, its impact remains to be elucidated. Here, we focused on the reported interaction between FOX-2 and ataxin-1, the disease-causing protein in spinocerebellar ataxia type 1. In this line, we further evaluated this interaction by yeast-2-hybrid analyses and co-immunoprecipitation experiments in mammalian cells. Interestingly, we discovered that FOX-2 localization and splicing activity is affected in the presence of nuclear ataxin-1 inclusions. Moreover, we observed that FOX-2 directly interacts with ataxin-2, a protein modulating spinocerebellar ataxia type 1 pathogenesis. Finally, we provide evidence that splicing of pre-mRNA of ataxin-2 depends on FOX-2 activity, since reduction of FOX-2 levels led to increased skipping of exon 18 in ataxin-2 transcripts. Most striking, we observed that ataxin-1 overexpression has an effect on this splicing event as well. Thus, our results demonstrate that FOX-2 is involved in splicing of ataxin-2 transcripts and that this splicing event is altered by overexpression of ataxin-1. PMID:22666429

FoxP1 marks medium spiny neurons from precursors to maturity and is required for their differentiation.

PubMed

Precious, S V; Kelly, C M; Reddington, A E; Vinh, N N; Stickland, R C; Pekarik, V; Scherf, C; Jeyasingham, R; Glasbey, J; Holeiter, M; Jones, L; Taylor, M V; Rosser, A E

2016-08-01

Identifying the steps involved in striatal development is important both for understanding the striatum in health and disease, and for generating protocols to differentiate striatal neurons for regenerative medicine. The most prominent neuronal subtype in the adult striatum is the medium spiny projection neuron (MSN), which constitutes more than 85% of all striatal neurons and classically expresses DARPP-32. Through a microarray study of genes expressed in the whole ganglionic eminence (WGE: the developing striatum) in the mouse, we identified the gene encoding the transcription factor Forkhead box protein P1 (FoxP1) as the most highly up-regulated gene, thus providing unbiased evidence for the association of FoxP1 with MSN development. We also describe the expression of FoxP1 in the human fetal brain over equivalent gestational stages. FoxP1 expression persisted through into adulthood in the mouse brain, where it co-localised with all striatal DARPP-32 positive projection neurons and a small population of DARPP-32 negative cells. There was no co-localisation of FoxP1 with any interneuron markers. FoxP1 was detectable in primary fetal striatal cells following dissection, culture, and transplantation into the adult lesioned striatum, demonstrating its utility as an MSN marker for transplantation studies. Furthermore, DARPP-32 expression was absent from FoxP1 knock-out mouse WGE differentiated in vitro, suggesting that FoxP1 is important for the development of DARPP-32-positive MSNs. In summary, we show that FoxP1 labels MSN precursors prior to the expression of DARPP-32 during normal development, and in addition suggest that FoxP1 labels a sub-population of MSNs that are not co-labelled by DARPP-32. We demonstrate the utility of FoxP1 to label MSNs in vitro and following neural transplantation, and show that FoxP1 is required for DARPP-32 positive MSN differentiation in vitro. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Inactivation of the FoxO3a transcription factor is associated with the production of reactive oxygen species during protein kinase CK2 downregulation-mediated senescence in human colon cancer and breast cancer cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Park, Seong-Yeol; Bae, Young-Seuk, E-mail: ysbae@knu.ac.kr

We previously showed that protein kinase CK2 downregulation mediates senescence through the reactive oxygen species (ROS)–p53–p21{sup Cip1/WAF1} pathway in various human cells. In the present study, we investigated whether the FoxO3a transcription factor is associated with ROS production during CK2 downregulation-induced senescence in human colon cancer HCT116 and breast cancer MCF-7 cells. FoxO3a overexpression suppressed ROS production and p53 stabilization induced by a CK2α knockdown. CK2α downregulation induced nuclear export of FoxO3a through stimulation of AKT-mediated phosphorylation of FoxO3a and decreased transcription of its target genes (Cu/ZnSOD, MnSOD, and catalase). In contrast, CK2α overexpression inhibited AKT-mediated FoxO3a phosphorylation. This resulted inmore » nuclear accumulation of FoxO3a, and elevated expression of its target genes. Therefore, these data indicate for the first time that CK2 downregulation stimulates ROS generation by inhibiting FoxO3a during premature senescence in human colon and breast cancer cells. - Highlights: • FoxO3a overexpression inhibited ROS production mediated by CK2α knockdown. • CK2α downregulation induced nuclear export of FoxO3a via AKT activation. • CK2α downregulation reduced transcription of FoxO3a target genes including SOD. • CK2α upregulation elevated nuclear import and target gene expression of FoxO3a. • This study indicates that CK2 can modulate the intracellular ROS level via FoxO3a.« less

Improved Anti-Treg Vaccination Targeting Foxp3 Efficiently Decreases Regulatory T Cells in Mice.

PubMed

Mousavi Niri, Neda; Memarnejadian, Arash; Pilehvar-Soltanahmadi, Younes; Agha Sadeghi, Mohammadreza; Mahdavi, Mehdi; Kheshtchin, Nasim; Arab, Samaneh; Namdar, Afshin; Jadidi, Farhad; Zarghami, Nosratollah; Hajati, Jamshid

2016-09-01

The critical role of regulatory T (Treg) cells in dampening immune responses against tumor cells is apparent. Therefore, several methods have been introduced for eliminating Treg. Among them, inducing immune responses against Treg cells expressing Foxp3 transcription factor is a hopeful approach to decrease the frequency of Tregs. In current study, we used the chimeric FoxP3-Fc(IgG) fusion construct/protein to effectively stimulate the immune responses against Treg cells. Previously constructed FoxP3-Fc(IgG) DNA vaccine and its protein counterpart were injected into C57BL/6 mice in a prime/boost regimen. After 2 weeks, the mice were killed to measure the frequency of Tregs in their spleens, as well as analyze their specific cytokine production, T-cell proliferation, and CD8 T-cell cytotoxicity against FoxP3 protein. FACS analysis of FoxP3 CD4 cells in splenocytes revealed the efficiency of FoxP3 DNA-prime protein-boost strategy to decrease the Treg cells and further showed considerable superiority of Fc(IgG) fusion strategy. This significant reduction in Treg frequency was also concomitant with higher FoxP3-specific CTL and Th1 responses in FoxP3-Fc vaccinated animals. Prime/boost vaccination against FoxP3 in addition to enhanced antigen presentation by means of Fc fusion strategy could be successfully considered for Treg depletion studies. Validity of this approach should be experimentally tested in preclinical tumor models.

SCP4 Promotes Gluconeogenesis Through FoxO1/3a Dephosphorylation.

PubMed

Cao, Jin; Yu, Yi; Zhang, Zhengmao; Chen, Xi; Hu, Zhaoyong; Tong, Qiang; Chang, Jiang; Feng, Xin-Hua; Lin, Xia

2018-01-01

FoxO1 and FoxO3a (collectively FoxO1/3a) proteins regulate a wide array of cellular processes, including hepatic gluconeogenesis. Phosphorylation of FoxO1/3a is a key event that determines its subcellular location and transcriptional activity. During glucose synthesis, the activity of FoxO1/3a is negatively regulated by Akt-mediated phosphorylation, which leads to the cytoplasmic retention of FoxO1/3a. However, the nuclear phosphatase that directly regulates FoxO1/3a remains to be identified. In this study, we discovered a nuclear phosphatase, SCP4/CTDSPL2 (SCP4), that dephosphorylated FoxO1/3a and promoted FoxO1/3a transcription activity. We found that SCP4 enhanced the transcription of FoxO1/3a target genes encoding PEPCK1 and G6PC, key enzymes in hepatic gluconeogenesis. Ectopic expression of SCP4 increased, while knockdown of SCP4 inhibited, glucose production. Moreover, we demonstrated that gene ablation of SCP4 led to hypoglycemia in neonatal mice. Consistent with the positive role of SCP4 in gluconeogenesis, expression of SCP4 was regulated under pathophysiological conditions. SCP4 expression was induced by glucose deprivation in vitro and in vivo and was elevated in obese mice caused by genetic (A vy ) and dietary (high-fat) changes. Thus, our findings provided experimental evidence that SCP4 regulates hepatic gluconeogenesis and could serve as a potential target for the prevention and treatment of diet-induced glucose intolerance and type 2 diabetes. © 2017 by the American Diabetes Association.

Activation of the Hedgehog Signaling Pathway in the Developing Lens Stimulates Ectopic FoxE3 Expression and Disruption in Fiber Cell Differentiation

PubMed Central

Kerr, Christine L.; Huang, Jian; Williams, Trevor; West-Mays, Judith A.

2012-01-01

Purpose. The signaling pathways and transcriptional effectors responsible for directing mammalian lens development provide key regulatory molecules that can inform our understanding of human eye defects. The hedgehog genes encode extracellular signaling proteins responsible for patterning and tissue formation during embryogenesis. Signal transduction of this pathway is mediated through activation of the transmembrane proteins smoothened and patched, stimulating downstream signaling resulting in the activation or repression of hedgehog target genes. Hedgehog signaling is implicated in eye development, and defects in hedgehog signaling components have been shown to result in defects of the retina, iris, and lens. Methods. We assessed the consequences of constitutive hedgehog signaling in the developing mouse lens using Cre-LoxP technology to express the conditional M2 smoothened allele in the embryonic head and lens ectoderm. Results. Although initial lens development appeared normal, morphological defects were apparent by E12.5 and became more significant at later stages of embryogenesis. Altered lens morphology correlated with ectopic expression of FoxE3, which encodes a critical gene required for human and mouse lens development. Later, inappropriate expression of the epithelial marker Pax6, and as well as fiber cell markers c-maf and Prox1 also occurred, indicating a failure of appropriate lens fiber cell differentiation accompanied by altered lens cell proliferation and cell death. Conclusions. Our findings demonstrate that the ectopic activation of downstream effectors of the hedgehog signaling pathway in the mouse lens disrupts normal fiber cell differentiation by a mechanism consistent with a sustained epithelial cellular developmental program driven by FoxE3. PMID:22491411

ADAM-17 is a poor prognostic indicator for patients with hilar cholangiocarcinoma and is regulated by FoxM1.

PubMed

Jiao, Xiaodong; Yu, Wenlong; Qian, Jianxin; Chen, Ying; Wei, Peilian; Fang, Wenzheng; Yu, Guanzhen

2018-05-18

A-disintegrin and metalloproteinases (ADAMs) are members of a family of multidomain transmembrane and secreted proteins. Specific ADAMs are upregulated in human cancers and correlated with tumor progression and poor outcome, but rarely studied in human hilar cholangiocarcinoma (HC). This study aimed to explore the expression profiles of ADAMs and their potential underlying mechanisms promoting cancer progression. mRNA expression of ADAM-9, - 10, - 11, - 12, - 15, - 17, - 28, and - 33 was analyzed in human hilar cholangiocarcinoma (HC) samples. Immunohistochemical (IHC) analysis was used to detect the expression of ADAM-10, - 17, - 28, and FoxM1 in HC. The regulation of ADAM-17 by FoxM1 and their functional study was investigated in vivo and in vitro. ADAM-10, - 17, and - 28 were upregulated in tumors compared with matched non-cancerous tissues. IHC analysis revealed increased expression of ADAM-10, - 17, and - 28 in HC cells, and ADAM17 seems to be an independent prognostic factor. ADAM-17 is regulated by FoxM1. A decrease in the expression of ADAM-17 by silencing FoxM1 led to an inhibition of cell proliferation, tumor growth, and the production of tumor necrosis factor α. IHC analysis showed co-expression of FoxM1 and ADAM-17 in HC specimens. The findings of the present study show an important role of the cross-talk among FoxM1, ADAM-17, and TNFa in HC development and progression.

RiceFOX: a database of Arabidopsis mutant lines overexpressing rice full-length cDNA that contains a wide range of trait information to facilitate analysis of gene function.

PubMed

Sakurai, Tetsuya; Kondou, Youichi; Akiyama, Kenji; Kurotani, Atsushi; Higuchi, Mieko; Ichikawa, Takanari; Kuroda, Hirofumi; Kusano, Miyako; Mori, Masaki; Saitou, Tsutomu; Sakakibara, Hitoshi; Sugano, Shoji; Suzuki, Makoto; Takahashi, Hideki; Takahashi, Shinya; Takatsuji, Hiroshi; Yokotani, Naoki; Yoshizumi, Takeshi; Saito, Kazuki; Shinozaki, Kazuo; Oda, Kenji; Hirochika, Hirohiko; Matsui, Minami

2011-02-01

Identification of gene function is important not only for basic research but also for applied science, especially with regard to improvements in crop production. For rapid and efficient elucidation of useful traits, we developed a system named FOX hunting (Full-length cDNA Over-eXpressor gene hunting) using full-length cDNAs (fl-cDNAs). A heterologous expression approach provides a solution for the high-throughput characterization of gene functions in agricultural plant species. Since fl-cDNAs contain all the information of functional mRNAs and proteins, we introduced rice fl-cDNAs into Arabidopsis plants for systematic gain-of-function mutation. We generated >30,000 independent Arabidopsis transgenic lines expressing rice fl-cDNAs (rice FOX Arabidopsis mutant lines). These rice FOX Arabidopsis lines were screened systematically for various criteria such as morphology, photosynthesis, UV resistance, element composition, plant hormone profile, metabolite profile/fingerprinting, bacterial resistance, and heat and salt tolerance. The information obtained from these screenings was compiled into a database named 'RiceFOX'. This database contains around 18,000 records of rice FOX Arabidopsis lines and allows users to search against all the observed results, ranging from morphological to invisible traits. The number of searchable items is approximately 100; moreover, the rice FOX Arabidopsis lines can be searched by rice and Arabidopsis gene/protein identifiers, sequence similarity to the introduced rice fl-cDNA and traits. The RiceFOX database is available at http://ricefox.psc.riken.jp/.

Elovl5 regulates the mTORC2-Akt-FOXO1 pathway by controlling hepatic cis-vaccenic acid synthesis in diet-induced obese mice[S

PubMed Central

Tripathy, Sasmita; Jump, Donald B.

2013-01-01

Elevated hepatic expression of fatty acid elongase-5 (Elovl5) induces FoxO1 phosphorylation, lowers FoxO1 nuclear content, and suppresses expression of genes involved in gluconeogenesis (GNG). In this report, we define the molecular and metabolic basis of Elovl5 control of FoxO1 phosphorylation. Adenoviral-mediated (Ad-Elovl5) induction of hepatic Elovl5 in diet-induced obese, glucose-intolerant mice and HepG2 cells increased the phosphorylation of Akt2-S473 [mammalian target of rapamycin complex-2 (mTORC2) site], but not Akt2-T308 (PDK1 site). The Akt2 inhibitor Akti1/2 blocked Elovl5 induction of FoxO1-S256 phosphorylation in HepG2 cells. Elevated Elovl5 activity in liver and HepG2 cells induced rictor mRNA, rictor protein, and rictor-mTOR interaction, whereas rictor knockdown (siRNA) attenuated Elovl5 induction of Akt2-S473 and FoxO1-S256 phosphorylation in HepG2 cells. FA analysis revealed that the abundance of cis-vaccenic acid (18:1,n-7) was increased in livers of obese mice and HepG2 cells following Ad-Elovl5 infection. Treating HepG2 cells with Elovl5 substrates established that palmitoleic acid (16:1,n-7), but not γ-linolenic acid (18:3,n-6), induced rictor protein, Akt-S473, and FoxO1-S256 phosphorylation. Inhibition of FA elongation blocked 16:1,n-7 but not 18:1,n-7 induction of rictor protein and Akt-S473 and FoxO1-S256 phosphorylation. These results establish a novel link between Elovl5-mediated synthesis of 18:1,n-7 and GNG through the control of the mTORC2-Akt-FoxO1 pathway. PMID:23099444

Minute Virus of Mice Inhibits Transcription of the Cyclin B1 Gene during Infection.

PubMed

Fuller, Matthew S; Majumder, Kinjal; Pintel, David J

2017-07-15

Replication of minute virus of mice (MVM) induces a sustained cellular DNA damage response (DDR) which the virus then exploits to prepare the nuclear environment for effective parvovirus takeover. An essential aspect of the MVM-induced DDR is the establishment of a potent premitotic block, which we previously found to be independent of activated p21 and ATR/Chk1 signaling. This arrest, unlike others reported previously, depends upon a significant, specific depletion of cyclin B1 and its encoding RNA, which precludes cyclin B1/CDK1 complex function, thus preventing mitotic entry. We show here that while the stability of cyclin B1 RNA was not affected by MVM infection, the production of nascent cyclin B1 RNA was substantially diminished at late times postinfection. Ectopic expression of NS1 alone did not reduce cyclin B1 expression. MVM infection also reduced the levels of cyclin B1 protein, and RNA levels normally increased in response to DNA-damaging reagents. We demonstrated that at times of reduced cyclin B1 expression during infection, there was a significantly reduced occupancy of RNA polymerase II and the essential mitotic transcription factor FoxM1 on the cyclin B1 gene promoter. Additionally, while total FoxM1 levels remained constant, there was a significant decrease of the phosphorylated, likely active, forms of FoxM1. Targeting of a constitutively active FoxM1 construct or the activation domain of FoxM1 to the cyclin B1 gene promoter via clustered regularly interspaced short palindromic repeats (CRISPR)-enzymatically inactive Cas9 in MVM-infected cells increased both cyclin B1 protein and RNA levels, implicating FoxM1 as a critical target for cyclin B1 inhibition during MVM infection. IMPORTANCE Replication of the parvovirus minute virus of mice (MVM) induces a sustained cellular DNA damage response (DDR) which the virus exploits to prepare the nuclear environment for effective takeover. An essential aspect of the MVM-induced DDR is establishment of a potent premitotic block. This block depends upon a significant, specific depletion of cyclin B1 and its encoding RNA that precludes cyclin B1/CDK1 complex functions necessary for mitotic entry. We show that reduced cyclin B1 expression is controlled primarily at the level of transcription initiation. Additionally, the essential mitotic transcription factor FoxM1 and RNA polymerase II were found to occupy the cyclin B1 gene promoter at reduced levels during infection. Recruiting a constitutively active FoxM1 construct or the activation domain of FoxM1 to the cyclin B1 gene promoter via CRISPR-catalytically inactive Cas9 (dCas9) in MVM-infected cells increased expression of both cyclin B1 protein and RNA, implicating FoxM1 as a critical target mediating MVM-induced cyclin B1 inhibition. Copyright © 2017 American Society for Microbiology.

Minute Virus of Mice Inhibits Transcription of the Cyclin B1 Gene during Infection

PubMed Central

Fuller, Matthew S.; Majumder, Kinjal

2017-01-01

ABSTRACT Replication of minute virus of mice (MVM) induces a sustained cellular DNA damage response (DDR) which the virus then exploits to prepare the nuclear environment for effective parvovirus takeover. An essential aspect of the MVM-induced DDR is the establishment of a potent premitotic block, which we previously found to be independent of activated p21 and ATR/Chk1 signaling. This arrest, unlike others reported previously, depends upon a significant, specific depletion of cyclin B1 and its encoding RNA, which precludes cyclin B1/CDK1 complex function, thus preventing mitotic entry. We show here that while the stability of cyclin B1 RNA was not affected by MVM infection, the production of nascent cyclin B1 RNA was substantially diminished at late times postinfection. Ectopic expression of NS1 alone did not reduce cyclin B1 expression. MVM infection also reduced the levels of cyclin B1 protein, and RNA levels normally increased in response to DNA-damaging reagents. We demonstrated that at times of reduced cyclin B1 expression during infection, there was a significantly reduced occupancy of RNA polymerase II and the essential mitotic transcription factor FoxM1 on the cyclin B1 gene promoter. Additionally, while total FoxM1 levels remained constant, there was a significant decrease of the phosphorylated, likely active, forms of FoxM1. Targeting of a constitutively active FoxM1 construct or the activation domain of FoxM1 to the cyclin B1 gene promoter via clustered regularly interspaced short palindromic repeats (CRISPR)-enzymatically inactive Cas9 in MVM-infected cells increased both cyclin B1 protein and RNA levels, implicating FoxM1 as a critical target for cyclin B1 inhibition during MVM infection. IMPORTANCE Replication of the parvovirus minute virus of mice (MVM) induces a sustained cellular DNA damage response (DDR) which the virus exploits to prepare the nuclear environment for effective takeover. An essential aspect of the MVM-induced DDR is establishment of a potent premitotic block. This block depends upon a significant, specific depletion of cyclin B1 and its encoding RNA that precludes cyclin B1/CDK1 complex functions necessary for mitotic entry. We show that reduced cyclin B1 expression is controlled primarily at the level of transcription initiation. Additionally, the essential mitotic transcription factor FoxM1 and RNA polymerase II were found to occupy the cyclin B1 gene promoter at reduced levels during infection. Recruiting a constitutively active FoxM1 construct or the activation domain of FoxM1 to the cyclin B1 gene promoter via CRISPR-catalytically inactive Cas9 (dCas9) in MVM-infected cells increased expression of both cyclin B1 protein and RNA, implicating FoxM1 as a critical target mediating MVM-induced cyclin B1 inhibition. PMID:28446681

Does Resveratrol Improve Insulin Signalling in HepG2 Cells?

PubMed

Norouzzadeh, Marjan; Amiri, Fatemehsadat; Saboor-Yaraghi, Ali Akbar; Shemirani, Farnoosh; Kalikias, Yas; Sharifi, Loghman; Seyyedsalehi, Monireh Sadat; Mahmoudi, Maryam

2017-04-01

Diabetes mellitus is a common metabolic disorder with high global prevalence. It is characterized by a decrease in insulin secretion or a decrease in insulin sensitivity or both. The aim of the present study was to investigate the effects of resveratrol treatment on the expression of the genes involved in insulin signalling cascade, such as Forkhead box protein O1 (FoxO1), 3-phosphoinositide-dependent protein kinase 1 (PDPK1) and mammalian target of rapamycin (mTOR). HepG2 cells were cultured in serum-free medium with high concentrations of glucose and insulin and then were treated with resveratrol (5, 10 and 20 µM) for 24 and 48 hours. Complementary deoxyribonucleic acids (cDNAs) were synthesized followed by RNA extraction. Real-time quantitative reverse transcription polymerase chain reaction was used to analyze the expression of FoxO1, PDPK1 and mTOR. Resveratrol increased the expression of PDPK1, mTOR and FoxO1. No significant difference was seen among differing dosages of resveratrol, but treatments for 48 hours exerted the greatest effectiveness. Our results were consistent with other studies showing the beneficial effects of resveratrol on diabetes. However, considering the effects of resveratrol in increasing FoxO1 and gluconeogenic gene expression, long-term usage of resveratrol should be investigated in greater depth in future studies. Copyright © 2016 Canadian Diabetes Association. Published by Elsevier Inc. All rights reserved.

FABP4 induces asthmatic airway epithelial barrier dysfunction via ROS-activated FoxM1.

PubMed

Wu, Gaohui; Yang, Liteng; Xu, Yi; Jiang, Xiaohong; Jiang, Xiaomin; Huang, Lisha; Mao, Ling; Cai, Shaoxi

2018-01-01

Functional abnormal airway epithelial cells, along with activated inflammatory cells, resulting in chronic airway inflammation, are considered as the characteristic of asthma. Fatty Acid Binding Protein 4 (FABP4) takes part in glucose and lipid homeostasis, and also have an important role in allergic airway inflammation. However, whether FABP4 influence barrier function of airway epithelial cells is unknown. In vivo, a HDM-induced murine model of asthma was obtained to assessed airway inflammation and protein expression of E-cadherin and Forkhead Box M1 (FoxM1). In vitro, 16-HBE was cultured and was treated with hrFABP4, siFABP4, FABPF4 inhibitor BMS, or FoxM1 inhibitor RCM-1. IL-4, IL-5, and IL-13 level was determined by ELISA. Transepithelial electrical resistance (TER), paracellular permeability and E-cadherin-special immunofluorescence were measured to value airway epithelial barrier function. Intracellular ROS production was determined by DCF-DA fluorescence. FABP4 inhibitor BMS alleviate airway inflammation and destruction of E-cad in allergic mouse. Treatment with HDM or hrFABP4 aggravated inflammatory response, damaged airway epithelial barrier, which could be inhibited by siFABP4 and BMS. Treatment with HDM or hrFABP4 also enhanced levels of FoxM1, and Inhibited FoxM1 suppressed HDM- and hrFABP4-induced inflammation and airway epithelial barrier dysfunction. In addition, H 2 O 2 promoted FoxM1 expression, HDM and hrFABP4 induced-FoxM1 could be inhibited by NAC, leading to decreased inflammation and improved airway epithelial barrier. Upregulated ROS induced by FABP4 was of significance in activating FoxM1 leading to airway inflammation and epithelial barrier dysfunction. Copyright © 2017 Elsevier Inc. All rights reserved.

Inactivation of the FoxO3a transcription factor is associated with the production of reactive oxygen species during protein kinase CK2 downregulation-mediated senescence in human colon cancer and breast cancer cells.

PubMed

Park, Seong-Yeol; Bae, Young-Seuk

2016-09-09

We previously showed that protein kinase CK2 downregulation mediates senescence through the reactive oxygen species (ROS)-p53-p21(Cip1/WAF1) pathway in various human cells. In the present study, we investigated whether the FoxO3a transcription factor is associated with ROS production during CK2 downregulation-induced senescence in human colon cancer HCT116 and breast cancer MCF-7 cells. FoxO3a overexpression suppressed ROS production and p53 stabilization induced by a CK2α knockdown. CK2α downregulation induced nuclear export of FoxO3a through stimulation of AKT-mediated phosphorylation of FoxO3a and decreased transcription of its target genes (Cu/ZnSOD, MnSOD, and catalase). In contrast, CK2α overexpression inhibited AKT-mediated FoxO3a phosphorylation. This resulted in nuclear accumulation of FoxO3a, and elevated expression of its target genes. Therefore, these data indicate for the first time that CK2 downregulation stimulates ROS generation by inhibiting FoxO3a during premature senescence in human colon and breast cancer cells. Copyright © 2016 Elsevier Inc. All rights reserved.

RiceFOX: A Database of Arabidopsis Mutant Lines Overexpressing Rice Full-Length cDNA that Contains a Wide Range of Trait Information to Facilitate Analysis of Gene Function

PubMed Central

Sakurai, Tetsuya; Kondou, Youichi; Akiyama, Kenji; Kurotani, Atsushi; Higuchi, Mieko; Ichikawa, Takanari; Kuroda, Hirofumi; Kusano, Miyako; Mori, Masaki; Saitou, Tsutomu; Sakakibara, Hitoshi; Sugano, Shoji; Suzuki, Makoto; Takahashi, Hideki; Takahashi, Shinya; Takatsuji, Hiroshi; Yokotani, Naoki; Yoshizumi, Takeshi; Saito, Kazuki; Shinozaki, Kazuo; Oda, Kenji; Hirochika, Hirohiko; Matsui, Minami

2011-01-01

Identification of gene function is important not only for basic research but also for applied science, especially with regard to improvements in crop production. For rapid and efficient elucidation of useful traits, we developed a system named FOX hunting (Full-length cDNA Over-eXpressor gene hunting) using full-length cDNAs (fl-cDNAs). A heterologous expression approach provides a solution for the high-throughput characterization of gene functions in agricultural plant species. Since fl-cDNAs contain all the information of functional mRNAs and proteins, we introduced rice fl-cDNAs into Arabidopsis plants for systematic gain-of-function mutation. We generated >30,000 independent Arabidopsis transgenic lines expressing rice fl-cDNAs (rice FOX Arabidopsis mutant lines). These rice FOX Arabidopsis lines were screened systematically for various criteria such as morphology, photosynthesis, UV resistance, element composition, plant hormone profile, metabolite profile/fingerprinting, bacterial resistance, and heat and salt tolerance. The information obtained from these screenings was compiled into a database named ‘RiceFOX’. This database contains around 18,000 records of rice FOX Arabidopsis lines and allows users to search against all the observed results, ranging from morphological to invisible traits. The number of searchable items is approximately 100; moreover, the rice FOX Arabidopsis lines can be searched by rice and Arabidopsis gene/protein identifiers, sequence similarity to the introduced rice fl-cDNA and traits. The RiceFOX database is available at http://ricefox.psc.riken.jp/. PMID:21186176

Pathological Ace2-to-Ace enzyme switch in the stressed heart is transcriptionally controlled by the endothelial Brg1–FoxM1 complex

PubMed Central

Yang, Jin; Feng, Xuhui; Zhou, Qiong; Cheng, Wei; Shang, Ching; Han, Pei; Lin, Chiou-Hong; Chen, Huei-Sheng Vincent; Quertermous, Thomas; Chang, Ching-Pin

2016-01-01

Genes encoding angiotensin-converting enzymes (Ace and Ace2) are essential for heart function regulation. Cardiac stress enhances Ace, but suppresses Ace2, expression in the heart, leading to a net production of angiotensin II that promotes cardiac hypertrophy and fibrosis. The regulatory mechanism that underlies the Ace2-to-Ace pathological switch, however, is unknown. Here we report that the Brahma-related gene-1 (Brg1) chromatin remodeler and forkhead box M1 (FoxM1) transcription factor cooperate within cardiac (coronary) endothelial cells of pathologically stressed hearts to trigger the Ace2-to-Ace enzyme switch, angiotensin I-to-II conversion, and cardiac hypertrophy. In mice, cardiac stress activates the expression of Brg1 and FoxM1 in endothelial cells. Once activated, Brg1 and FoxM1 form a protein complex on Ace and Ace2 promoters to concurrently activate Ace and repress Ace2, tipping the balance to Ace2 expression with enhanced angiotensin II production, leading to cardiac hypertrophy and fibrosis. Disruption of endothelial Brg1 or FoxM1 or chemical inhibition of FoxM1 abolishes the stress-induced Ace2-to-Ace switch and protects the heart from pathological hypertrophy. In human hypertrophic hearts, BRG1 and FOXM1 expression is also activated in endothelial cells; their expression levels correlate strongly with the ACE/ACE2 ratio, suggesting a conserved mechanism. Our studies demonstrate a molecular interaction of Brg1 and FoxM1 and an endothelial mechanism of modulating Ace/Ace2 ratio for heart failure therapy. PMID:27601681

Pathological Ace2-to-Ace enzyme switch in the stressed heart is transcriptionally controlled by the endothelial Brg1-FoxM1 complex.

PubMed

Yang, Jin; Feng, Xuhui; Zhou, Qiong; Cheng, Wei; Shang, Ching; Han, Pei; Lin, Chiou-Hong; Chen, Huei-Sheng Vincent; Quertermous, Thomas; Chang, Ching-Pin

2016-09-20

Genes encoding angiotensin-converting enzymes (Ace and Ace2) are essential for heart function regulation. Cardiac stress enhances Ace, but suppresses Ace2, expression in the heart, leading to a net production of angiotensin II that promotes cardiac hypertrophy and fibrosis. The regulatory mechanism that underlies the Ace2-to-Ace pathological switch, however, is unknown. Here we report that the Brahma-related gene-1 (Brg1) chromatin remodeler and forkhead box M1 (FoxM1) transcription factor cooperate within cardiac (coronary) endothelial cells of pathologically stressed hearts to trigger the Ace2-to-Ace enzyme switch, angiotensin I-to-II conversion, and cardiac hypertrophy. In mice, cardiac stress activates the expression of Brg1 and FoxM1 in endothelial cells. Once activated, Brg1 and FoxM1 form a protein complex on Ace and Ace2 promoters to concurrently activate Ace and repress Ace2, tipping the balance to Ace2 expression with enhanced angiotensin II production, leading to cardiac hypertrophy and fibrosis. Disruption of endothelial Brg1 or FoxM1 or chemical inhibition of FoxM1 abolishes the stress-induced Ace2-to-Ace switch and protects the heart from pathological hypertrophy. In human hypertrophic hearts, BRG1 and FOXM1 expression is also activated in endothelial cells; their expression levels correlate strongly with the ACE/ACE2 ratio, suggesting a conserved mechanism. Our studies demonstrate a molecular interaction of Brg1 and FoxM1 and an endothelial mechanism of modulating Ace/Ace2 ratio for heart failure therapy.

Testosterone regulation of Akt/mTORC1/FoxO3a Signaling in Skeletal Muscle

PubMed Central

White, James P.; Gao, Song; Puppa, Melissa J.; Sato, Shuichi; Welle, Stephen L.; Carson, James A.

2012-01-01

Low endogenous testosterone production, known as hypogonadism is commonly associated with conditions inducing muscle wasting. Akt signaling can control skeletal muscle mass through mTOR regulation of protein synthesis and FoxO regulation of protein degradation, and this pathway has been previously identified as a target of androgen signaling. However, the testosterone sensitivity of Akt/mTOR signaling requires further understanding in order to grasp the significance of varied testosterone levels seen with wasting disease on muscle protein turnover regulation. Therefore, the purpose of this study is to determine the effect of androgen availability on muscle Akt/mTORC1/FoxO3a regulation in skeletal muscle and cultured C2C12 myotubes. C57BL/6 mice were either castrated for 42 days or castrated and treated with the nandrolone decanoate (ND) (6 mg/kg bw/wk). Testosterone loss (TL) significantly decreased volitional grip strength, body weight, and gastrocnemius (GAS) muscle mass, and ND reversed these changes. Related to muscle mass regulation, TL decreased muscle IGF-1 mRNA, the rate of myofibrillar protein synthesis, Akt phosphorylation, and the phosphorylation of Akt targets, GSK3β, PRAS40 and FoxO3a. TL induced expression of FoxO transcriptional targets, MuRF1, atrogin1 and REDD1. Muscle AMPK and raptor phosphorylation, mTOR inhibitors, were not altered by low testosterone. ND restored IGF-1 expression and Akt/mTORC1 signaling while repressing expression of FoxO transcriptional targets. Testosterone (T) sensitivity of Akt/mTORC1 signaling was examined in C2C12 myotubes, and mTOR phosphorylation was induced independent of Akt activation at low T concentrations, while a higher T concentration was required to activate Akt signaling. Interestingly, low concentration T was sufficient to amplify myotube mTOR and Akt signaling after 24h of T withdrawal, demonstrating the potential in cultured myotubes for a T initiated positive feedback mechanism to amplify Akt/mTOR signaling. In summary, androgen withdrawal decreases muscle myofibrillar protein synthesis through Akt/mTORC1 signaling, which is independent of AMPK activation, and readily reversible by anabolic steroid administration. Acute Akt activation in C2C12 myotubes is sensitive to a high concentration of testosterone, and low concentrations of testosterone can activate mTOR signaling independent of Akt. PMID:23116773

Insulin-like Growth Factor 1 Regulates the Expression of ATP-Binding Cassette Transporter A1 in Pancreatic Beta Cells.

PubMed

Lyu, J; Imachi, H; Iwama, H; Zhang, H; Murao, K

2016-05-01

ATP-binding cassette transporter A1 (ABCA1) in pancreatic beta cells influences insulin secretion and cholesterol homeostasis. The present study investigates whether insulin-like growth factor 1 (IGF-1), which mediates stimulation of ABCA1 gene expression, could also interfere with the phosphatidylinositol 3-kinase (PI3-K) cascade.ABCA1 expression was examined by real-time polymerase chain reaction (PCR), Western blot analysis, and a reporter gene assay in rat insulin-secreting INS-1 cells incubated with IGF-1. The binding of forkhead box O1 (FoxO1) protein to the ABCA1 promoter was assessed by a chromatin immunoprecipitation (ChIP) assay. ABCA1 protein levels increased in response to rising concentrations of IGF-1. Real-time PCR analysis showed a significant increase in ABCA1 mRNA expression. However, both effects were suppressed after silencing the IGF-1 receptor. In parallel with its effect on endogenous ABCA1 mRNA levels, IGF-1 induced the activity of a reporter construct containing the ABCA1 promoter, while it was abrogated by LY294002, a specific inhibitor of PI3-K. Constitutively active Akt stimulated activity of the ABCA1 promoter, and a dominant-negative mutant of Akt or mutagenesis of the FoxO1 response element in the ABCA1 promoter abolished the ability of IGF-1 to stimulate promoter activity. A ChIP assay showed that FoxO1 mediated its transcriptional activity by directly binding to the ABCA1 promoter region. The knockdown of FoxO1 disrupted the effect of IGF-1 on ABCA1 expression. Furthermore, IGF-1 promoted cholesterol efflux and reduced the pancreatic lipotoxicity. These results demonstrate that the PI3-K/Akt/FoxO1 pathway contributes to the regulation of ABCA1 expression in response to IGF-1 stimulation. © Georg Thieme Verlag KG Stuttgart · New York.

Regulation of glucose metabolism via hepatic forkhead transcription factor 1 (FoxO1) by Morinda citrifolia (noni) in high-fat diet-induced obese mice.

PubMed

Nerurkar, Pratibha V; Nishioka, Adrienne; Eck, Philip O; Johns, Lisa M; Volper, Esther; Nerurkar, Vivek R

2012-07-01

Renewed interest in alternative medicine among diabetic individuals prompted us to investigate anti-diabetic effects of Morinda citrifolia (noni) in high-fat diet (HFD)-fed mice. Type 2 diabetes is associated with increased glucose production due to the inability of insulin to suppress hepatic gluconeogenesis and promote glycolysis. Insulin inhibits gluconeogenesis by modulating transcription factors such as forkhead box O (FoxO1). Based on microarray analysis data, we tested the hypothesis that fermented noni fruit juice (fNJ) improves glucose metabolism via FoxO1 phosphorylation. C57BL/6 male mice were fed a HFD and fNJ for 12 weeks. Body weights and food intake were monitored daily. FoxO1 expression was analysed by real-time PCR and Western blotting. Specificity of fNJ-associated FoxO1 regulation of gluconeogenesis was confirmed by small interfering RNA (siRNA) studies using human hepatoma cells, HepG2. Supplementation with fNJ inhibited weight gain and improved glucose and insulin tolerance and fasting glucose in HFD-fed mice. Hypoglycaemic properties of fNJ were associated with the inhibition of hepatic FoxO1 mRNA expression, with a concomitant increase in FoxO1 phosphorylation and nuclear expulsion of the proteins. Gluconeogenic genes, phosphoenolpyruvate C kinase (PEPCK) and glucose-6-phosphatase (G6P), were significantly inhibited in mice fed a HFD+fNJ. HepG2 cells demonstrated more than 80 % inhibition of PEPCK and G6P mRNA expression in cells treated with FoxO1 siRNA and fNJ. These data suggest that fNJ improves glucose metabolism via FoxO1 regulation in HFD-fed mice.

Regulation of glucose metabolism via hepatic forkhead transcription factor 1 (FoxO1) by Morinda citrifolia (noni) in high-fat diet-induced obese mice

PubMed Central

Nerurkar, Pratibha V.; Nishioka, Adrienne; Eck, Philip O.; Nerurkar, Vivek R.

2016-01-01

Renewed interest in alternative medicine among diabetic individuals prompted us to investigate anti-diabetic effects of Morinda citrifolia (noni) in high-fat diet (HFD)-fed mice. Type 2 diabetes is associated with increased glucose production due to the inability of insulin to suppress hepatic gluconeogenesis and promote glycolysis. Insulin inhibits gluconeogenesis by modulating transcription factors such as forkhead box O (FoxO1). Based on microarray analysis data, we tested the hypothesis that fermented noni fruit juice (fNJ) improves glucose metabolism via FoxO1 phosphorylation. C57BL/6 male mice were fed a HFD and fNJ for 12 weeks. Body weights and food intake were monitored daily. FoxO1 expression was analysed by real-time PCR and Western blotting. Specificity of fNJ-associated FoxO1 regulation of gluconeogenesis was confirmed by small interfering RNA (siRNA) studies using human hepatoma cells, HepG2. Supplementation with fNJ inhibited weight gain and improved glucose and insulin tolerance and fasting glucose in HFD-fed mice. Hypoglycaemic properties of fNJ were associated with the inhibition of hepatic FoxO1 mRNA expression, with a concomitant increase in FoxO1 phosphorylation and nuclear expulsion of the proteins. Gluconeogenic genes, phosphoenolpyruvate C kinase (PEPCK) and glucose-6-phosphatase (G6P), were significantly inhibited in mice fed a HFD + fNJ. HepG2 cells demonstrated more than 80% inhibition of PEPCK and G6P mRNA expression in cells treated with FoxO1 siRNA and fNJ. These data suggest that fNJ improves glucose metabolism via FoxO1 regulation in HFD-fed mice. PMID:22011624

Differential expression of genes associated with lipid metabolism in longissimus dorsi of Korean bulls and steers.

PubMed

Bong, Jin Jong; Jeong, Jin Young; Rajasekar, Panchamoorthy; Cho, Young Moo; Kwon, Eung Gi; Kim, Hyeong Cheol; Paek, Bong Hyun; Baik, Myunggi

2012-07-01

The objective of this study was to compare expression of genes associated with lipid deposition and removal between bulls and steers in the longissimus dorsi muscle (LM) tissue of Korean cattle. Castration increased the expression of lipid uptake lipoprotein lipase, fatty acid translocase, and fatty acid transport protein 1 in LM. Castration increased lipogenic gene expression of both acetyl-CoA carboxylase and fatty acid synthase. In contrast, castration downregulated lipolytic gene expression of both adipose triglyceride lipase (ATGL) and monoglyceride lipase. Steers showed higher expression levels of insulin signaling phospho-v-akt murine thymoma viral oncogene homolog 1 than bulls but lower protein levels of nuclear Forkhead box O 1 (FoxO1) than bulls, suggesting that increased insulin signaling following castration decreases nuclear FoxO1 levels, leading to downregulation of ATGL gene expression. These findings suggest that castration contributes to increases in lipid uptake and lipogenesis and a decrease in lipolysis, resulting in improved marbling. Copyright © 2012 Elsevier Ltd. All rights reserved.

Glucocorticoids Enhance Muscle Proteolysis through a Myostatin-Dependent Pathway at the Early Stage.

PubMed

Wang, Ruxia; Jiao, Hongchao; Zhao, Jingpeng; Wang, Xiaojuan; Lin, Hai

2016-01-01

Myostatin, a member of the TGF-β superfamily of secreted proteins, is expressed primarily in skeletal muscle. It negatively regulates muscle mass and is associated with glucocorticoid-induced muscle atrophy. However, it remains unclear whether myostatin is involved in glucocorticoid-induced muscle protein turnover. The aim of the present study was to investigate the role of myostatin in protein metabolism during dexamethasone (DEX) treatment. Protein synthesis rates and the expression of the genes for myostatin, ubiquitin-proteasome atrogin-1, MuRF1, FoxO1/3a and mTOR/p70S6K were determined. The results show that DEX decreased (P<0.05) protein synthesis rates while increasing the abundance of myostatin. DEX increased (P<0.05) the level of phospho-FoxO1/3a (Thr 24/32) and the expression of MuRF1. In contrast, DEX treatment had no detectable effect on atrogin-1 protein levels (P>0.05). The phosphorylation levels of mTOR and p70S6K were decreased by DEX treatment (P<0.05). Follistatin treatment inhibited the DEX-induced increase in myostatin (P<0.05) and the activation of phosphor-FoxO1/3a (Thr 24/32) (P< 0.05) and MuRF1 (P<0.05). Follistatin treatment had no influence on the protein synthesis rate or on the phosphorylation levels of mTOR (Ser 2448) and p70S6K (Thr 389) (P> 0.05). In conclusion, the present study suggests that the myostatin signalling pathway is associated with glucocorticoid-induced muscle protein catabolism at the beginning of exposure. Myostatin is not a main pathway associated with the suppression of muscle protein synthesis by glucocorticoids.

Glucocorticoids Enhance Muscle Proteolysis through a Myostatin-Dependent Pathway at the Early Stage

PubMed Central

Wang, Ruxia; Jiao, Hongchao; Zhao, Jingpeng; Wang, Xiaojuan; Lin, Hai

2016-01-01

Myostatin, a member of the TGF-β superfamily of secreted proteins, is expressed primarily in skeletal muscle. It negatively regulates muscle mass and is associated with glucocorticoid-induced muscle atrophy. However, it remains unclear whether myostatin is involved in glucocorticoid-induced muscle protein turnover. The aim of the present study was to investigate the role of myostatin in protein metabolism during dexamethasone (DEX) treatment. Protein synthesis rates and the expression of the genes for myostatin, ubiquitin-proteasome atrogin-1, MuRF1, FoxO1/3a and mTOR/p70S6K were determined. The results show that DEX decreased (P<0.05) protein synthesis rates while increasing the abundance of myostatin. DEX increased (P<0.05) the level of phospho-FoxO1/3a (Thr 24/32) and the expression of MuRF1. In contrast, DEX treatment had no detectable effect on atrogin-1 protein levels (P>0.05). The phosphorylation levels of mTOR and p70S6K were decreased by DEX treatment (P<0.05). Follistatin treatment inhibited the DEX-induced increase in myostatin (P<0.05) and the activation of phosphor-FoxO1/3a (Thr 24/32) (P< 0.05) and MuRF1 (P<0.05). Follistatin treatment had no influence on the protein synthesis rate or on the phosphorylation levels of mTOR (Ser 2448) and p70S6K (Thr 389) (P> 0.05). In conclusion, the present study suggests that the myostatin signalling pathway is associated with glucocorticoid-induced muscle protein catabolism at the beginning of exposure. Myostatin is not a main pathway associated with the suppression of muscle protein synthesis by glucocorticoids. PMID:27227776

Regulatory T-lymphocytes mediate amyotrophic lateral sclerosis progression and survival

PubMed Central

Henkel, Jenny S; Beers, David R; Wen, Shixiang; Rivera, Andreana L; Toennis, Karen M; Appel, Joan E; Zhao, Weihua; Moore, Dan H; Powell, Suzanne Z; Appel, Stanley H

2013-01-01

In amyotrophic lateral sclerosis (ALS) mice, regulatory T-lymphocytes (Tregs) are neuroprotective, slowing disease progression. To address whether Tregs and FoxP3, a transcription factor required for Treg function, similarly influence progression rates of ALS patients, T-lymphocytes from patients were assessed by flow cytometry. Both numbers of Tregs and their FoxP3 protein expressions were reduced in rapidly progressing ALS patients and inversely correlated with progression rates. The mRNA levels of FoxP3, TGF-β, IL4 and Gata3, a Th2 transcription factor, were reduced in rapidly progressing patients and inversely correlated with progression rates. Both FoxP3 and Gata3 were accurate indicators of progression rates. No differences in IL10, Tbx21, a Th1 transcription factor or IFN-γ expression were found between slow and rapidly progressing patients. A 3.5-year prospective study with a second larger cohort revealed that early reduced FoxP3 levels were indicative of progression rates at collection and predictive of future rapid progression and attenuated survival. Collectively, these data suggest that Tregs and Th2 lymphocytes influence disease progression rates. Importantly, early reduced FoxP3 levels could be used to identify rapidly progressing patients. PMID:23143995

Development of canine herpesvirus based antifertility vaccines for foxes using bacterial artificial chromosomes.

PubMed

Strive, Tanja; Hardy, Christopher M; French, Nigel; Wright, John D; Nagaraja, Nitin; Reubel, Gerhard H

2006-02-13

Using bacterial artificial chromosome (BAC) technology, a canine herpesvirus (CHV)-based recombinant vaccine vector was produced for the development of an antifertility vaccine for foxes. Infectious viruses were recovered following transfection of canid cells with a BAC plasmid carrying the complete CHV genome. In vitro growth characteristics of BAC-derived viruses were similar to that of wildtype (wt)-CHV. Two recombinant antigens, fox zona pellucida protein subunit 3 (fZPC) and enhanced green fluorescent protein (EGFP) as control antigen, were inserted into thymidine kinase (TK) locus of the CHV genome and shown to be efficiently expressed in vitro. Inoculation of foxes with transgenic CHVs induced CHV specific antibodies, but was innocuous and failed to elicit transgene-specific antibody responses. Infectious virus or viral DNA was not detected in mucosal secretions or tissues of vaccinated foxes. The CHV-BAC system proved to be a quick and reliable method to manipulate the CHV genome. It will help to readily apply changes in the vector design in order to improve virus replication in vivo.

Dendrobium mixture regulates hepatic gluconeogenesis in diabetic rats via the phosphoinositide-3-kinase/protein kinase B signaling pathway.

PubMed

Lin, Xinjun; Shi, Hong; Cui, Yi; Wang, Xiaoning; Zhang, Jieping; Yu, Wenzhen; Wei, Min

2018-07-01

The present study aimed to evaluate the impact of dendrobium mixture (DMix) on the gene and protein expression of insulin signaling pathway-associated factors in the livers of diabetic rats. The molecular mechanisms by which DMix inhibits gluconeogenesis were also investigated. A total of 47 female Wistar rats were used in the present study. Of these, 11 rats were randomly selected as healthy controls and diabetes was induced in the remaining 36 rats by administering a high-fat and high-sugar diet for 6 weeks, followed by two intraperitoneal injections of streptozotocin. The 36 rats were screened for diabetes and then randomly divided into three groups: Model, metformin and DMix groups. Following 12 weeks of treatment, the fasting blood glucose (FBG), glycosylated serum protein (GSP), serum insulin, blood lipids [total cholesterol (Tch) and triglycerides (TG)], alanine transaminase (ALT) and aspartate transaminase (AST) were assessed. In addition, hematoxylin and eosin staining was used for histomorphological examination of the liver tissues. The mRNA expression of insulin receptor (InsR), forkhead box protein O1 (FoxO1), phosphoenolpyruvate carboxykinase (PEPCK) and glucose 6-phosphatase (G6Pase) in the liver was measured with reverse transcription-quantitative polymerase chain reaction and the protein expression of InsR, phosphoinositide-3-kinase (PI3K), phosphorylated (p)-PI3K, protein kinase B (Akt), p-Akt, FoxO1, PEPCK and G6Pase in the liver was measured by western blot analysis. The FBG, GSP, InsR, Tch, TG, ALT and AST levels were significantly lower in the DMix-treated group compared with the model group (P<0.05). In addition, DMix treatment notably improved liver histopathology and significantly increased the gene and protein expression of InsR, PI3K and Akt (P<0.05). DMix treatment also significantly reduced the gene and protein expression of FoxO1, PEPCK and G6Pase (P<0.05). DMix effectively reduced FBG and blood lipids and significantly improved liver function and insulin resistance in diabetic rats, possibly by regulating the gene and protein expression of molecules associated with the PI3K/Akt signaling pathway.

CD147 (Basigin/Emmprin) identifies FoxP3+CD45RO+CTLA4+-activated human regulatory T cells.

PubMed

Solstad, Therese; Bains, Simer Jit; Landskron, Johannes; Aandahl, Einar Martin; Thiede, Bernd; Taskén, Kjetil; Torgersen, Knut Martin

2011-11-10

Human CD4(+)FoxP3(+) T cells are functionally and phenotypically heterogeneous providing plasticity to immune activation and regulation. To better understand the functional dynamics within this subset, we first used a combined strategy of subcellular fractionation and proteomics to describe differences at the protein level between highly purified human CD4(+)CD25(+) and CD4(+)CD25(-) T-cell populations. This identified a set of membrane proteins highly expressed on the cell surface of human regulatory T cells (Tregs), including CD71, CD95, CD147, and CD148. CD147 (Basigin or Emmprin) divided CD4(+)CD25(+) cells into distinct subsets. Furthermore, CD147, CD25, FoxP3, and in particular CTLA-4 expression correlated. Phenotypical and functional analyses suggested that CD147 marks the switch between resting (CD45RA(+)) and activated (CD45RO(+)) subsets within the FoxP3(+) T-cell population. Sorting of regulatory T cells into CD147(-) and CD147(+) populations demonstrated that CD147 identifies an activated and highly suppressive CD45RO(+) Treg subset. When analyzing CD4(+) T cells for their cytokine producing potential, CD147 levels grouped the FoxP3(+) subset into 3 categories with different ability to produce IL-2, TNF-α, IFN-γ, and IL-17. Together, this suggests that CD147 is a direct marker for activated Tregs within the CD4(+)FoxP3(+) subset and may provide means to manipulate cells important for immune homeostasis.

Cloning and expression of canine CD25 for validation of an anti-human CD25 antibody to compare T regulatory lymphocytes in healthy dogs and dogs with osteosarcoma.

PubMed

Rissetto, K C; Rindt, H; Selting, K A; Villamil, J A; Henry, C J; Reinero, C R

2010-05-15

T regulatory cells (Tregs) are a unique subset of T helper cells that serve to modify/inhibit effector cells of the immune system and thus are essential to prevent autoimmunity. Overzealous Treg activity may contribute to impaired immune responses to cancer. Tregs can be phenotypically identified by proteins expressed on the cell surface (CD4 and CD25) and inside the cell (forkhead box3 (FoxP3)), although in dogs, no anti-canine CD25 antibody exists. We hypothesized that a mouse anti-human CD25 antibody definitively recognizes the canine protein and can be used to identify Tregs in dogs. We describe cloning and transfection of the canine CD25 gene into human HeLa cells with subsequent expression of the canine protein on the cell surface detected using an anti-human CD25 antibody in a flow cytometric assay. Validation of this antibody was used to identify CD4+CD25+FoxP3+ Tregs in 39 healthy dogs and 16 dogs with osteosarcoma (OSA). Results were expressed in five different ways and showed significantly fewer %CD4+CD25+ T lymphocytes expressing FoxP3 in blood of older dogs (>/=7 years) compared with the other two age groups (<2 and 2-6 years) (p<0.001) and fewer %CD4+CD25+FoxP3+ Tregs in the tumor draining lymph nodes of OSA patients compared to the unrelated lymph node (p=0.049). However, there was no significant difference in % Tregs in the peripheral blood or lymph nodes between the control dogs and those with OSA. While the CD25 antibody can be successfully used in a flow cytometric assay to identify Tregs, this study does not support clinical utility of phenotypic recognition of Tregs in dogs with OSA. Copyright 2010 Elsevier B.V. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Guo, Feng; Zhang, Yuanyuan; Wang, Qingzhu

Objective: This study was designed to investigate the protective effect of forkhead transcription factor O1 (FoxO1) on podocyte injury in rats with diabetic nephropathy. Methods: Streptozotocin-induced diabetic rats were served as DM group, while DM rats transfected with blank lentiviral vectors (LV-pSC-GFP) or lentiviral vectors carrying constitutively active FoxO1 (LV-CA-FoxO1) were served as LV-NC group or LV-CA group, respectively. The control group (NG) consisted of uninduced rats that received an injection of diluent buffer. At 2, 4, and 8 weeks after transfection, the levels of urine albumin, blood glucose, blood urea nitrogen, serum creatinine and urine podocalyxin were measured. Real-timemore » PCR and western blotting were performed to measure mRNA and protein levels of FoxO1, podocalyxin, nephrin, and desmin in renal cortex. In addition, light and electron microscopy were used to detect structural changes in the glomerulus and podocytes. Results: Compared with the rats in LV-NC and DM groups, LV-CA rats showed a significant increase in FoxO1 mRNA and protein levels and a distinct decrease in urine albumin, blood urea nitrogen, and serum creatinine (except at the two-week time point) levels (p < 0.05). Podocalyxin and nephrin mRNA and protein levels increased (p < 0.05), whereas desmin mRNA and protein levels decreased (p < 0.05). Pathological changes in glomerulus were also ameliorated in LV-CA group. Conclusions: Upregulating expression of FoxO1 by transduction with recombinant lentivirus ameliorates podocyte injury in diabetic rats. - Highlights: • The structures and functions of podocytes were impaired in STZ-induced diabetic rats. • Constitutively active FoxO1 ameliorates structure injury and preserves function of podocytes in diabetic rats. • FoxO1 may alleviate the pathological changes associated with diabetic nephropathy.« less

Analysis of lamprey clustered Fox genes: insight into Fox gene evolution and expression in vertebrates.

PubMed

Wotton, Karl R; Shimeld, Sebastian M

2011-12-01

In the human genome, members of the FoxC, FoxF, FoxL1, and FoxQ1 gene families are found in two paralagous clusters. One cluster contains the genes FOXQ1, FOXF2, FOXC1 and the second consists of FOXF1, FOXC2, and FOXL1. In jawed vertebrates these genes are known to be expressed in different pharyngeal tissues and all, except FoxQ1, are involved in patterning the early embryonic mesoderm. We have previously traced the evolution of this cluster in the bony vertebrates, and the gene content is identical in the dogfish, a member of the most basally branching lineage of the jawed vertebrates. Here we extend these analyses to jawless vertebrates. Using genomic searches and molecular approaches we have identified homologues of these genes from lampreys. We identify two FoxC genes, two FoxF genes, two FoxQ1 genes and single FoxL1 gene. We examine the embryonic expression of one predominantly mesodermally expressed gene family, FoxC, and the endodermally expressed member of the cluster, FoxQ1. We identified FoxQ1 transcripts in the pharyngeal endoderm, while the two FoxC genes are differentially expressed in the pharyngeal mesenchyme and ectoderm. Furthermore we identify conserved expression of lamprey FoxC genes in the paraxial and intermediate mesoderms. We interpret our results through a chordate-wide comparison of expression patterns and discuss gene content in the context of theories on the evolution of the vertebrate genome. 2011 Elsevier B.V. All rights reserved.

bicaudal-C is required for the formation of anterior neurogenic ectoderm in the sea urchin embryo.

PubMed

Yaguchi, Shunsuke; Yaguchi, Junko; Inaba, Kazuo

2014-10-31

bicaudal-C (bicC) mRNA encodes a protein containing RNA-binding domains that is reported to be maternally present with deflection in the oocytes/eggs of some species. The translated protein plays a critical role in the regulation of cell fate specification along the body axis during early embryogenesis in flies and frogs. However, it is unclear how it functions in eggs in which bicC mRNA is uniformly distributed, for instance, sea urchin eggs. Here, we show the function of BicC in the formation of neurogenic ectoderm of the sea urchin embryo. Loss-of-function experiments reveal that BicC is required for serotonergic neurogenesis and for expression of ankAT-1 gene, which is essential for the formation of apical tuft cilia in the neurogenic ectoderm of the sea urchin embryo. In contrast, the expression of FoxQ2, the neurogenic ectoderm specification transcription factor, is invariant in BicC morphants. Because FoxQ2 is an upstream factor of serotonergic neurogenesis and ankAT-1 expression, these data indicate that BicC functions in regulating the events that are coordinated by FoxQ2 during sea urchin embryogenesis.

FoxP2 expression in the cerebellum and inferior olive: development of the transverse stripe-shaped expression pattern in the mouse cerebellar cortex.

PubMed

Fujita, Hirofumi; Sugihara, Izumi

2012-02-15

Many molecules are expressed heterogeneously in subpopulations of cerebellar Purkinje cells (PCs) and inferior olive (IO) neurons during development or in adulthood. These expression patterns are often organized in longitudinal stripes in the cerebellar cortex, which may be related to functional compartmentalization. FoxP2, a transcription factor, is expressed in PCs and IO neurons, but the details of its expression pattern remain unclear. Here we examined FoxP2 expression patterns systematically by immunostaining serial sections of the hindbrain from embryonic day 14.5 to adulthood in mice. FoxP2 was highly expressed in virtually all PCs at and before postnatal day 6 (P6), except for those in the flocculus and small parts of the nodulus (vermal lobule X), where FoxP2 expression was moderate or absent. After P6, FoxP2 expression gradually diminished in PCs in some areas. In adults, FoxP2 was expressed, less intensely than in earlier stages, in subsets of PCs that were mostly arranged transversely along the folial apices. In contrast, FoxP2 was expressed intensely in most IO neurons during development and in adulthood. FoxP2 was also expressed in a small population of neurons in the cerebellar nuclei. FoxP2 expression in adult rats and chicks was generally comparable to that in adult mice, suggesting evolutionary conservation of the expression pattern. Thus, the FoxP2 expression pattern reflects new transverse compartmentalization in the adult cerebellar cortex, although its functional significance remains unclear. Copyright © 2011 Wiley-Liss, Inc.

FoxM1 Promotes Glioma Cells Progression by Up-Regulating Anxa1 Expression

PubMed Central

Cheng, Shi-Xiang; Tu, Yue; Zhang, Sai

2013-01-01

Forkhead box M1 (FoxM1) is a member of the forkhead transcription factor family and is overexpression in malignant gliomas. However, the molecular mechanisms by which FoxM1lead to glioma carcinogenesis and progression are still not well known. In the present study, we show that Anxa1 was overexpression in gliomas and predicted the poor outcome. Furthermore, Anxa1 closely related to the FoxM1 expression and was a direct transcriptional target of FoxM1. Overexpression of FoxM1 up-regulated Anxa1 expression, whereas suppression of FoxM1 expression down-regulated Anxa1 expression in glioma cells. Finally, FoxM1 enhanced the proliferation, migration, and angiogenesis in Anxa1-dependent manner both in vitro and in vivo. Our findings provide both clinical and mechanistic evidences that FoxM1 contributes to glioma development by directly up-regulating Anxa1 expression. PMID:23991102

Forkhead Transcription Factors: Formulating a FOXO Target for Cognitive Loss.

PubMed

Maiese, Kenneth

2017-01-01

With almost 47 million individuals worldwide suffering from some aspect of dementia, it is clear that cognitive loss impacts a significant proportion of the global population. Unfortunately, definitive treatments to resolve or prevent the onset of cognitive loss are limited. In most cases such care is currently non-existent prompting the need for novel treatment strategies. Mammalian forkhead transcription factors of the O class (FoxO) are one such avenue of investigation that offer an exciting potential to bring new treatments forward for disorders that involve cognitive loss. Here we examine the background, structure, expression, and function of FoxO transcription factors and their role in cognitive loss, programmed cell death in the nervous system with apoptosis and autophagy, and areas to target FoxOs for dementia and specific disorders such as Alzheimer's disease. FoxO proteins work in concert with a number of other cell survival pathways that involve growth factors, such as erythropoietin and neurotrophins, silent mating type information regulation 2 homolog 1 (Saccharomyces cerevisiae) (SIRT1), Wnt1 inducible signaling pathway protein 1 (WISP1), Wnt signaling, and cancer-related pathways. FoxO transcription factors oversee proinflammatory pathways, affect nervous system amyloid (Aβ) production and toxicity, lead to mitochondrial dysfunction, foster neuronal apoptotic cell death, and accelerate the progression of degenerative disease. However, under some scenarios such as those involving autophagy, FoxOs also can offer protection in the nervous system and reduce toxic intracellular protein accumulations and potentially limit Aβ toxicity. Given the ability of FoxOs to not only promote apoptotic cell death in the nervous system, but also through the induction of autophagy offer protection against degenerative disease that can lead to dementia, a fine balance in the activity of FoxOs may be required to target cognitive loss in individuals. Future work should yield exciting new prospects for FoxO proteins as new targets to treat the onset and progression of cognitive loss and dementia. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

USP7 Attenuates Hepatic Gluconeogenesis Through Modulation of FoxO1 Gene Promoter Occupancy

PubMed Central

Hall, Jessica A.; Tabata, Mitsuhisa; Rodgers, Joseph T.

2014-01-01

Hepatic forkhead protein FoxO1 is a key component of systemic glucose homeostasis via its ability to regulate the transcription of rate-limiting enzymes in gluconeogenesis. Important in the regulation of FoxO1 transcriptional activity are the modifying/demodifying enzymes that lead to posttranslational modification. Here, we demonstrate the functional interaction and regulation of FoxO1 by herpesvirus-associated ubiquitin-specific protease 7 (USP7; also known as herpesvirus-associated ubiquitin-specific protease, HAUSP), a deubiquitinating enzyme. We show that USP7-mediated mono-deubiquitination of FoxO1 results in suppression of FoxO1 transcriptional activity through decreased FoxO1 occupancy on the promoters of gluconeogenic genes. Knockdown of USP7 in primary hepatocytes leads to increased expression of FoxO1-target gluconeogenic genes and elevated glucose production. Consistent with this, USP7 gain-of-function suppresses the fasting/cAMP-induced activation of gluconeogenic genes in hepatocyte cells and in mouse liver, resulting in decreased hepatic glucose production. Notably, we show that the effects of USP7 on hepatic glucose metabolism depend on FoxO1. Together, these results place FoxO1 under the intimate regulation of deubiquitination and glucose metabolic control with important implication in diseases such as diabetes. PMID:24694308

Determination of DNA Binding Behavior of FoxA1 Constructs Using a Gold Nanoparticle-Based High Throughput Assay

NASA Astrophysics Data System (ADS)

Aung, Khin Moh Moh; Lim, Michelle Gek Liang; Hong, Shuzhen; Cheung, Edwin; Su, Xiaodi

Forkhead box protein 1 (FoxA1) is a member of the forkhead family of winged-helix transcription factors. It plays crucial roles in the development and differentiation of multiple organs and in the regulation of estrogen-stimulated genes. In this study, in order to determine the regions of FoxA1 necessary for efficient Deoxyribonucleic Acid (DNA) binding, we cloned, expressed and purified a series of FoxA1 constructs that contain either the DNA Binding Domain (DBD), the Transcription Activation Domain (TAD), or both. We determined the DNA binding behavior of these constructs using traditional electrophoretic mobility shift assay (EMSA) and a recently developed gold nanoparticles (AuNPs)-based fast screening method. We conclude that just the DBD region alone is not sufficient for protein-DNA binding activity. Amino acids flanking the upstream of the DBD region are required for maximal DNA binding activity. Through this study, we have also further validated the AuNPs assay for its generality and expanded the existing protocol for comparing the DNA binding behavior of multiple proteins of different charge properties and molecular weights.

FoxO1 integrates direct and indirect effects of insulin on hepatic glucose production and glucose utilization

PubMed Central

O-Sullivan, InSug; Zhang, Wenwei; Wasserman, David H.; Liew, Chong Wee; Liu, Jonathan; Paik, Jihye; DePinho, Ronald A.; Stolz, Donna Beer; Kahn, C. Ronald; Schwartz, Michael W.; Unterman, Terry G.

2016-01-01

FoxO proteins are major targets of insulin action. To better define the role of FoxO1 in mediating insulin effects in the liver, we generated liver-specific insulin receptor knockout (LIRKO) and IR/FoxO1 double knockout (LIRFKO) mice. Here we show that LIRKO mice are severely insulin resistant based on glucose, insulin and C-peptide levels, and glucose and insulin tolerance tests, and genetic deletion of hepatic FoxO1 reverses these effects. 13C-glucose and insulin clamp studies indicate that regulation of both hepatic glucose production (HGP) and glucose utilization is impaired in LIRKO mice, and these defects are also restored in LIRFKO mice corresponding to changes in gene expression. We conclude that (1) inhibition of FoxO1 is critical for both direct (hepatic) and indirect effects of insulin on HGP and utilization, and (2) extrahepatic effects of insulin are sufficient to maintain normal whole-body and hepatic glucose metabolism when liver FoxO1 activity is disrupted. PMID:25963540

Esculetin ameliorates hepatic fibrosis in high fat diet induced non-alcoholic fatty liver disease by regulation of FoxO1 mediated pathway.

PubMed

Pandey, Anuradha; Raj, Priyank; Goru, Santosh Kumar; Kadakol, Almesh; Malek, Vajir; Sharma, Nisha; Gaikwad, Anil Bhanudas

2017-08-01

Non-alcoholic fatty liver disease (NAFLD), a chronic metabolic disorder is associated with oxidative stress, inflammation and fibrotic cascades. In this study, we aimed to examine the effects of Esculetin, a well-known anti-oxidant on TGF-β1 mediated liver fibrosis and FoxO1 activity. A non-genetic murine model for NAFLD was developed by chronic high fat diet (HFD) (58% calories from fats) feeding in Wistar rats. The plasma biochemical parameters, liver function tests, oxidative stress, and histopathological alterations were assessed. The alterations in extracellular matrix (ECM) deposition and FoxO1 activity were assessed by immunohistochemistry. The aberrations in plasma parameters, liver functioning, morphometric and microscopic changes in liver structure of HFD fed rats were significantly improved by treatment with Esculetin. Liver fibrosis, identified in the form of collagen deposition and expression of fibrotic proteins like TGF-β1 and fibronectin was also markedly controlled by Esculetin. The expression of phospho-FoxO1 was found to be reduced in HFD fed rats' liver, showing an increase in activation of FoxO1 under insulin resistant and hyperglycemic states. Esculetin treatment could improve phospho-FoxO1 expression, thus showing its ability to act on Akt/PI3K/FoxO1 pathway. As per the previous studies, a potential therapy for NAFLD may be the one with multi-faceted actions on insulin resistance, oxidative stress, inflammation and fibrosis. This study demonstrates the efficiency of Esculetin in improving liver fibrosis in HFD induced NAFLD. Copyright © 2017 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

[Relationship between FoxO1 Expression and Wound Age during Skin Incised Wound Healing].

PubMed

Chen, Y; Ji, X Y; Fan, Y Y; Yu, L S

2018-02-01

To investigate FoxO1 expression and its time-dependent changes during the skin incised wound healing. After the establishment of the skin incised wound model in mice, the FoxO1 expression of skin in different time periods was detected by immunohistochemistry and Western blotting. Immunohistochemistry staining showed that FoxO1 was weakly expressed in a few fibroblasts of epidermis, hair follicles, sebaceous glands, vessel endothelium and dermis in the control group. The FoxO1 expression was enhanced in the epidermis and skin appendages around the wound during 6-12 h after injury, which could be detected in the infiltrating neutrophils and a small number of monocytes. FoxO1 was mainly expressed in monocytes during 1-3 d after injury, and in neovascular endothelial cells and fibroblasts during 5-10 d. On the 14th day after injury, the FoxO1 expression still could be detected in a few fibroblasts. The Western blotting results showed that the FoxO1 expression quantity of the tissue samples in injury group was higher than in control group. The FoxO1 expression peaked at 12 h and 7 d after injury. FoxO1 is time-dependently expressed in skin wound healing, which can be a useful marker for wound age determination. Copyright© by the Editorial Department of Journal of Forensic Medicine.

Characterization of the FoxL2 proximal promoter and coding sequence from the common snapping turtle (Chelydra serpentina).

PubMed

Guo, Lei; Rhen, Turk

2017-10-01

Sex is determined by temperature during embryogenesis in snapping turtles, Chelydra serpentina. Previous studies in this species show that dihydrotestosterone (DHT) induces ovarian development at temperatures that normally produce males or mixed sex ratios. The feminizing effect of DHT is associated with increased expression of FoxL2, suggesting that androgens regulate transcription of FoxL2. To test this hypothesis, we cloned the proximal promoter (1.6kb) and coding sequence for snapping turtle FoxL2 (tFoxL2) in frame with mCherry to produce a fluorescent reporter. The tFoxL2-mCherry fusion plasmid or mCherry control plasmid were stably transfected into mouse KK1 granulosa cells. These cells were then treated with 0, 1, 10, or 100nM DHT to assess androgen effects on tFoxL2-mCherry expression. In contrast to the main hypothesis, DHT did not alter expression of the tFoxL2-mCherry reporter. However, normal serum increased expression of tFoxL2-mCherry when compared to charcoal-stripped serum, indicating that the cloned region of tFoxL2 contains cis regulatory elements. We also used the tFoxL2-mCherry plasmid as an expression vector to test the hypothesis that DHT and tFoxL2 interact to regulate expression of endogenous genes in granulosa cells. While tFoxL2-mCherry and DHT had independent effects on mouse FoxL2, FshR, GnRHR, and StAR expression, tFoxL2-mCherry potentiated low concentration DHT effects on mouse aromatase expression. Further studies will be required to determine whether synergistic regulation of aromatase by DHT and FoxL2 also occurs in turtle gonads during the sex-determining period, which would explain the feminizing effect of DHT in this species. Copyright © 2017 Elsevier Inc. All rights reserved.

Forkhead box-P3+ regulatory T cells and toll-like receptor 2 co-expression in oral squamous cell carcinoma.

PubMed

Hussaini, H M; Parachuru, V P B; Seymour, G J; Rich, A M

2017-04-01

The function of forkhead box-P3 (FoxP3) regulatory T cells (Treg) and toll-like receptor (TLR)2 protein in the oral cancer microenvironment is not fully understood, but evidence from other malignancies suggests it is likely they are involved with tumour development and progression. The aim of this study was to investigate the distribution of FoxP3 + cells, TLR2 + cells and double-labelled FoxP3 + TLR2 + immune cells in oral squamous cell carcinoma (OSCC), using immunohistochemistry (IHC) and immunofluorescence (IF). 25 archival cases of OSCC were immunostained with anti-FoxP3 and anti-TLR2 antibodies. Inflamed hyperplastic oral mucosal tissues were used as controls. The proportion of single-labelled, double-labelled and negative cells was determined. A higher frequency of double-labelled FoxP3 + TLR2 + Tregs was observed within the immune cells of OSCC compared to inflamed controls using IHC (p<0.05). Cell-to-cell contact between single-stained TLR2 + cells and FoxP3 + cells was noted. Double IF studies validated demonstration of co-expression of FoxP3 + /TLR2 + immune cells in OSCC. The presence of FoxP3 + TLR2 + cells within the OSCC microenvironment may represent a dendritic cell-dependent pathway capable of inhibiting Treg suppressive activity, potentially enhancing the anti-tumour response. Modulation of TLR2-Treg interactions should be further explored to determine if they have a role in the therapeutic management of OSCC. Copyright © 2017 Elsevier GmbH. All rights reserved.

Annexin A11 knockdown inhibits in vitro proliferation and enhances survival of Hca-F cell via Akt2/FoxO1 pathway and MMP-9 expression.

PubMed

Liu, Shuqing; Wang, Jiasheng; Guo, Chunmei; Qi, Houbao; Sun, Ming-Zhong

2015-03-01

Annexin A11 (Anxa11), a Ca(2+)-regulated phospholipid-binding protein, is involved in cell apoptosis, differentiation, vesicle trafficking, cancer progression and autoimmune diseases. Previous study from our group indicated that Anxa11 was associated with lymphatic metastatic potential of murine hepatocarcinoma cells. Herein, we investigated the effects and action mechanism of Anxa11 knockdown on in vitro cell proliferation and apoptosis of Hca-F, a murine hepatocarcinoma cell with∼75% lymph node metastatic potential. Real-time PCR and western blotting assays indicated that Anxa11 was significantly downregulated in monoclonal Anxa11-shRNA-transfected Hca-F cells. Anxa11 knockdown in Hca-F suppressed its in vitro proliferation and cell apoptosis capacities. Following Anxa11 knockdown in Hca-F cells, Bax/Bcl-2 expression level ratio, Akt2 and FoxO1 (pSer319) expression levels as well as MMP-9 mRNA and active MMP-9 protein levels were significantly elevated in Hca-F cells. In conclusion, Annexin A11 knockdown inhibits the in vitro proliferation and cell apoptosis of Hca-F cell via Akt2/FoxO1 and/or MMP-9 expression pathway. Anxa11 might play an important role in hepatocarcinoma cell invasion and metastasis and hepatocarcinoma malignancy. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Myostatin Activates the Ubiquitin-Proteasome and Autophagy-Lysosome Systems Contributing to Muscle Wasting in Chronic Kidney Disease

PubMed Central

Wang, Dong-Tao; Yang, Ya-Jun; Huang, Ren-Hua; Zhang, Zhi-Hua; Lin, Xin

2015-01-01

Our evidence demonstrated that CKD upregulated the expression of myostatin, TNF-α, and p-IkBa and downregulated the phosphorylation of PI3K, Akt, and FoxO3a, which were also associated with protein degradation and muscle atrophy. The autophagosome formation and protein expression of autophagy-related genes were increased in muscle of CKD rats. The mRNA level and protein expression of MAFbx and MuRF-1 were also upregulated in CKD rats, as well as proteasome activity of 26S. Moreover, activation of myostatin elicited by TNF-α induces C2C12 myotube atrophy via upregulating the expression of autophagy-related genes, including MAFbx and MuRF1 and proteasome subunits. Inactivation of FoxO3a triggered by PI3K inhibitor LY294002 prevented the myostatin-induced increase of expression of MuRF1, MAFbx, and LC3-II protein in C2C12 myotubes. The findings were further consolidated by using siRNA interference and overexpression of myostatin. Additionally, expression of myostatin was activated by TNF-α via a NF-κB dependent pathway in C2C12 myotubes, while inhibition of NF-κB activity suppressed myostatin and improved myotube atrophy. Collectively, myostatin mediated CKD-induced muscle catabolism via coordinate activation of the autophagy and the ubiquitin-proteasome systems. PMID:26448817

Myostatin Activates the Ubiquitin-Proteasome and Autophagy-Lysosome Systems Contributing to Muscle Wasting in Chronic Kidney Disease.

PubMed

Wang, Dong-Tao; Yang, Ya-Jun; Huang, Ren-Hua; Zhang, Zhi-Hua; Lin, Xin

2015-01-01

Our evidence demonstrated that CKD upregulated the expression of myostatin, TNF-α, and p-IkBa and downregulated the phosphorylation of PI3K, Akt, and FoxO3a, which were also associated with protein degradation and muscle atrophy. The autophagosome formation and protein expression of autophagy-related genes were increased in muscle of CKD rats. The mRNA level and protein expression of MAFbx and MuRF-1 were also upregulated in CKD rats, as well as proteasome activity of 26S. Moreover, activation of myostatin elicited by TNF-α induces C2C12 myotube atrophy via upregulating the expression of autophagy-related genes, including MAFbx and MuRF1 and proteasome subunits. Inactivation of FoxO3a triggered by PI3K inhibitor LY294002 prevented the myostatin-induced increase of expression of MuRF1, MAFbx, and LC3-II protein in C2C12 myotubes. The findings were further consolidated by using siRNA interference and overexpression of myostatin. Additionally, expression of myostatin was activated by TNF-α via a NF-κB dependent pathway in C2C12 myotubes, while inhibition of NF-κB activity suppressed myostatin and improved myotube atrophy. Collectively, myostatin mediated CKD-induced muscle catabolism via coordinate activation of the autophagy and the ubiquitin-proteasome systems.

Ethanol Stimulates Endoplasmic Reticulum Inositol Triphosphate and Sigma Receptors to Promote Withdrawal-Associated Loss of Neuron-Specific Nuclear Protein/Fox-3.

PubMed

Reynolds, Anna R; Saunders, Meredith A; Prendergast, Mark A

2016-07-01

Prior studies demonstrate that ethanol (EtOH) exposure induces the release of intracellular calcium (CA(2+) ) in modulation of γ-aminobutyric acid-ergic tone and produces concomitant alterations in sigma (σ)-1 protein expression that may contribute to the development EtOH dependence. However, the influence of CA(2+) released from endoplasmic reticulum (ER)-bound inositol triphosphate (IP3) and σ-1 receptors in regulating hippocampal function has yet to be delineated. Rat hippocampal explants were subjected to chronic intermittent EtOH (CIE) exposure with or without the addition of IP3 inhibitor xestospongin C (0 to 0.5 μM) or σ-1 receptor antagonist BD-1047 (0 to 80 μM). Hippocampal viability was assessed via immunohistochemical labeling of neuron-specific nuclear protein (NeuN)/Fox-3 in CA1, CA3, and dentate gyrus (DG) subregions. Exposure to CIE produced consistent and significant decreases of NeuN/Fox-3 in each primary cell layer of the hippocampal formation. Co-exposure to xestospongin reversed these effects in the CA1 subregion and significantly attenuated these effects in the CA3 and DG regions. Xestospongin application also significantly increased NeuN/Fox-3 immunofluorescence in EtOH-naïve hippocampi. Co-exposure to 20 μM BD-1047 also reversed the loss of NeuN/Fox-3 during CIE exposure in each hippocampal cell layer, whereas exposure to 80 μM BD-1047 did not alter NeuN/Fox-3 in EtOH-treated hippocampi. By contrast, 80 μM BD-1047 application significantly increased NeuN/Fox-3 immunofluorescence in EtOH-naïve hippocampi in each subregion. These data suggest that EtOH stimulates ER IP3 and σ-1 receptors to promote hippocampal loss of NeuN/Fox-3 during CIE. Copyright © 2016 by the Research Society on Alcoholism.

FoxP2 and olfaction: divergence of FoxP2 expression in olfactory tubercle between different feeding habit bats.

PubMed

Chen, Qi; Wang, Lina; Jones, G; Metzner, W; Xuan, F J; Yin, Jiangxia; Sun, Y

2013-12-01

FoxP2 is a member of the winged helix/forkhead class of transcription factors. Despite FoxP2 is found to have particular relevance to speech and language, the role of this gene is broader and not yet fully elucidated. In this study, we investigated the expression of FoxP2 in the brains of bats with different feeding habits (two frugivorous species and three insectivorous species). We found FoxP2 expression in the olfactory tubercle of frugivorous species is significantly higher than that in insectivorous species. Difference of FoxP2 expression was not observed within each of the frugivorous or insectivorous group. The diverse expression patterns in olfactory tubercle between two kinds of bats indicate FoxP2 has a close relation with olfactory tubercle associated functions, suggesting its important role in sensory integration within the olfactory tubercle and such a discrepancy of FoxP2 expression in olfactory tubercle may take responsibility for the different feeding behaviors of frugivorous and insectivorous bats.

Protein kinase WNK3 regulates the neuronal splicing factor Fox-1.

PubMed

Lee, A-Young; Chen, Wei; Stippec, Steve; Self, Jon; Yang, Fan; Ding, Xiaojun; Chen, She; Juang, Yu-Chi; Cobb, Melanie H

2012-10-16

We report an action of the protein kinase WNK3 on the neuronal mRNA splicing factor Fox-1. Fox-1 splices mRNAs encoding proteins important in synaptic transmission and membrane excitation. WNK3, implicated in the control of neuronal excitability through actions on ion transport, binds Fox-1 and inhibits its splicing activity in a kinase activity-dependent manner. Phosphorylation of Fox-1 by WNK3 does not change its RNA binding capacity; instead, WNK3 increases the cytoplasmic localization of Fox-1, thereby suppressing Fox-1-dependent splicing. These findings demonstrate a role of WNK3 in RNA processing. Considering the implication of WNK3 and Fox-1 in disorders of neuronal development such as autism, WNK3 may offer a target for treatment of Fox-1-induced disease.

Losartan activates sirtuin 1 in rat reduced-size orthotopic liver transplantation

PubMed Central

Pantazi, Eirini; Bejaoui, Mohamed; Zaouali, Mohamed Amine; Folch-Puy, Emma; Pinto Rolo, Anabela; Panisello, Arnau; Palmeira, Carlos Marques; Roselló-Catafau, Joan

2015-01-01

AIM: To investigate a possible association between losartan and sirtuin 1 (SIRT1) in reduced-size orthotopic liver transplantation (ROLT) in rats. METHODS: Livers of male Sprague-Dawley rats (200-250 g) were preserved in University of Wisconsin preservation solution for 1 h at 4 °C prior to ROLT. In an additional group, an antagonist of angiotensin II type 1 receptor (AT1R), losartan, was orally administered (5 mg/kg) 24 h and 1 h before the surgical procedure to both the donors and the recipients. Transaminase (as an indicator of liver injury), SIRT1 activity, and nicotinamide adenine dinucleotide (NAD+, a co-factor necessary for SIRT1 activity) levels were determined by biochemical methods. Protein expression of SIRT1, acetylated FoxO1 (ac-FoxO1), NAMPT (the precursor of NAD+), heat shock proteins (HSP70, HO-1) expression, endoplasmic reticulum stress (GRP78, IRE1α, p-eIF2) and apoptosis (caspase 12 and caspase 3) parameters were determined by Western blot. Possible alterations in protein expression of mitogen activated protein kinases (MAPK), such as p-p38 and p-ERK, were also evaluated. Furthermore, the SIRT3 protein expression and mRNA levels were examined. RESULTS: The present study demonstrated that losartan administration led to diminished liver injury when compared to ROLT group, as evidenced by the significant decreases in alanine aminotransferase (358.3 ± 133.44 vs 206 ± 33.61, P < 0.05) and aspartate aminotransferase levels (893.57 ± 397.69 vs 500.85 ± 118.07, P < 0.05). The lessened hepatic injury in case of losartan was associated with enhanced SIRT1 protein expression and activity (5.27 ± 0.32 vs 6.08 ± 0.30, P < 0.05). This was concomitant with increased levels of NAD+ (0.87 ± 0.22 vs 1.195 ± 0.144, P < 0.05) the co-factor necessary for SIRT1 activity, as well as with decreases in ac-FoxO1 expression. Losartan treatment also provoked significant attenuation of endoplasmic reticulum stress parameters (GRP78, IRE1α, p-eIF2) which was consistent with reduced levels of both caspase 12 and caspase 3. Furthermore, losartan administration stimulated HSP70 protein expression and attenuated HO-1 expression. However, no changes were observed in protein or mRNA expression of SIRT3. Finally, the protein expression pattern of p-ERK and p-p38 were not altered upon losartan administration. CONCLUSION: The present study reports that losartan induces SIRT1 expression and activity, and that it reduces hepatic injury in a ROLT model. PMID:26185373

Losartan activates sirtuin 1 in rat reduced-size orthotopic liver transplantation.

PubMed

Pantazi, Eirini; Bejaoui, Mohamed; Zaouali, Mohamed Amine; Folch-Puy, Emma; Pinto Rolo, Anabela; Panisello, Arnau; Palmeira, Carlos Marques; Roselló-Catafau, Joan

2015-07-14

To investigate a possible association between losartan and sirtuin 1 (SIRT1) in reduced-size orthotopic liver transplantation (ROLT) in rats. Livers of male Sprague-Dawley rats (200-250 g) were preserved in University of Wisconsin preservation solution for 1 h at 4 °C prior to ROLT. In an additional group, an antagonist of angiotensin II type 1 receptor (AT1R), losartan, was orally administered (5 mg/kg) 24 h and 1 h before the surgical procedure to both the donors and the recipients. Transaminase (as an indicator of liver injury), SIRT1 activity, and nicotinamide adenine dinucleotide (NAD(+), a co-factor necessary for SIRT1 activity) levels were determined by biochemical methods. Protein expression of SIRT1, acetylated FoxO1 (ac-FoxO1), NAMPT (the precursor of NAD+), heat shock proteins (HSP70, HO-1) expression, endoplasmic reticulum stress (GRP78, IRE1α, p-eIF2) and apoptosis (caspase 12 and caspase 3) parameters were determined by Western blot. Possible alterations in protein expression of mitogen activated protein kinases (MAPK), such as p-p38 and p-ERK, were also evaluated. Furthermore, the SIRT3 protein expression and mRNA levels were examined. The present study demonstrated that losartan administration led to diminished liver injury when compared to ROLT group, as evidenced by the significant decreases in alanine aminotransferase (358.3 ± 133.44 vs 206 ± 33.61, P < 0.05) and aspartate aminotransferase levels (893.57 ± 397.69 vs 500.85 ± 118.07, P < 0.05). The lessened hepatic injury in case of losartan was associated with enhanced SIRT1 protein expression and activity (5.27 ± 0.32 vs 6.08 ± 0.30, P < 0.05). This was concomitant with increased levels of NAD(+) (0.87 ± 0.22 vs 1.195 ± 0.144, P < 0.05) the co-factor necessary for SIRT1 activity, as well as with decreases in ac-FoxO1 expression. Losartan treatment also provoked significant attenuation of endoplasmic reticulum stress parameters (GRP78, IRE1α, p-eIF2) which was consistent with reduced levels of both caspase 12 and caspase 3. Furthermore, losartan administration stimulated HSP70 protein expression and attenuated HO-1 expression. However, no changes were observed in protein or mRNA expression of SIRT3. Finally, the protein expression pattern of p-ERK and p-p38 were not altered upon losartan administration. The present study reports that losartan induces SIRT1 expression and activity, and that it reduces hepatic injury in a ROLT model.

Segregated Regulatory CD39+ CD4+ T Cell Function: TGF-β-Producing FoxP3− and IL-10-Producing FoxP3+ Cells Are Interdependent for Protection Against Collagen-Induced Arthritis1

PubMed Central

Kochetkova, Irina; Thornburg, Theresa; Callis, Gayle; Pascual, David W.

2011-01-01

Oral immunization with a Salmonella vaccine vector expressing enterotoxigenic E. coli colonization factor antigen I (CFA/I) can protect against collagen-induced arthritis (CIA) by dampening IL-17 and IFN-γ via enhanced IL-4, IL-10, and TGF-β. To identify the responsible regulatory CD4+ T cells making the host refractory to CIA, Salmonella-CFA/I induced CD39+CD4+ T cells with enhanced apyrase activity relative to Salmonella vector-immunized mice. Adoptive transfer of vaccine-induced CD39+CD4+ T cells into CIA mice conferred complete protection, while CD39−CD4+ T cells did not. Subsequent analysis of vaccinated FoxP3-GFP mice revealed the CD39+ T cells were composed of FoxP3-GFP− and FoxP3-GFP+ subpopulations. Although each adoptively transferred Salmonella-CFA/I-induced FoxP3− and FoxP3+CD39+CD4+ T cells could protect against CIA, each subset was not as efficacious as total CD39+CD4+ T cells, suggesting their interdependence for optimal protection. Cytokine analysis revealed FoxP3− CD39+CD4+ T cells produced TGF-β, and FoxP3+CD39+CD4+ T cells produced IL-10, showing a segregation of function. Moreover, donor FoxP3-GFP− CD4+ T cells converted to FoxP3-GFP+ CD39+CD4+ T cells in the recipients, showing plasticity of these regulatory T cells. TGF-β was found to be essential for protection since in vivo TGF-β neutralization reversed activation of cAMP-response element-binding protein (CREB) and reduced the development of CD39+CD4+ T cells. Thus, CD39 apyrase-expressing CD4+ T cells stimulated by Salmonella-CFA/I are composed of TGF-β-producing FoxP3− CD39+CD4+ T cells and support the stimulation of IL-10-producing FoxP3+ CD39+CD4+ T cells. PMID:21967895

Decreased frequencies and impaired functions of the CD31+ subpopulation in Treg cells associated with decreased FoxP3 expression and enhanced Treg cell defects in patients with coronary heart disease.

PubMed

Huang, L; Zheng, Y; Yuan, X; Ma, Y; Xie, G; Wang, W; Chen, H; Shen, L

2017-03-01

Coronary heart disease (CHD) is one of the most common types of organ lesions caused by atherosclerosis, in which CD4 + CD25 + forkhead box protein 3 (FoxP3 + ) regulatory T cells (T reg ) play an atheroprotective role. However, T reg cell numbers are decreased and their functions are impaired in atherosclerosis; the underlying mechanisms remain unclear. CD31 plays an important part in T cell response and contributes to maintaining T cell tolerance. The immunomodulatory effects of CD31 are also implicated in atherosclerosis. In this study, we found that decreased frequencies of the CD31 + subpopulation in T reg cells (CD31 + Tr cells) correlated positively with decreased FoxP3 expression in CHD patients. Cell culture in vitro demonstrated CD31 + Tr cells maintaining stable FoxP3 expression after activation and exhibited enhanced proliferation and immunosuppression compared with the CD31 - subpopulation in T reg cells (CD31 - Tr cells). We also confirmed impaired secretion of transforming growth factor (TGF)-β1 and interleukin (IL)-10 in CD31 + Tr cells of CHD patients. Further analysis revealed reduced phospho-SHP2 (associated with CD31 activation) and phospho-signal transducer and activator of transcription-5 (STAT-5) (associated with FoxP3 transcription) levels in CD31 + Tr cells of CHD patients, suggesting that decreased FoxP3 expression in CD31 + Tr cells might be because of attenuated SHP2 and STAT-5 activation. These data indicate that decreased frequencies and impaired functions of the CD31 + Tr subpopulation associated with decreased FoxP3 expression give rise, at least in part, to T reg cell defects in CHD patients. Our findings emphasize the important role of the CD31 + Tr subpopulation in maintaining T reg cell normal function and may provide a novel explanation for impaired immunoregulation of T reg cells in CHD. © 2016 British Society for Immunology.

Forkhead transcription factor foxe1 regulates chondrogenesis in zebrafish.

PubMed

Nakada, Chisako; Iida, Atsumi; Tabata, Yoko; Watanabe, Sumiko

2009-12-15

Forkhead transcription factor (Fox) e1 is a causative gene for Bamforth-Lazarus syndrome, which is characterized by hypothyroidism and cleft palate. Applying degenerate polymerase chain reaction using primers specific for the conserved forkhead domain, we identified zebrafish foxe1 (foxe1). Foxe1 is expressed in the thyroid, pharynx, and pharyngeal skeleton during development; strongly expressed in the gill and weakly expressed in the brain, eye, and heart in adult zebrafish. A loss of function of foxe1 by morpholino antisense oligo (MO) exhibited abnormal craniofacial development, shortening of Meckel's cartilage and the ceratohyals, and suppressed chondrycytic proliferation. However, at 27 hr post fertilization, the foxe1 MO-injected embryos showed normal dlx2, hoxa2, and hoxb2 expression, suggesting that the initial steps of pharyngeal skeletal development, including neural crest migration and specification of the pharyngeal arch occurred normally. In contrast, at 2 dpf, a severe reduction in the expression of sox9a, colIIaI, and runx2b, which play roles in chondrocytic proliferation and differentiation, was observed. Interestingly, fgfr2 was strongly upregulated in the branchial arches of the foxe1 MO-injected embryos. Unlike Foxe1-null mice, normal thyroid development in terms of morphology and thyroid-specific marker expression was observed in foxe1 MO-injected zebrafish embryos. Taken together, our results indicate that Foxe1 plays an important role in chondrogenesis during development of the pharyngeal skeleton in zebrafish, probably through regulation of fgfr2 expression. Furthermore, the roles reported for FOXE1 in mammalian thyroid development may have been acquired during evolution. (c) 2009 Wiley-Liss, Inc.

FoxP3 Expression in Macrophages, Cancer, and B Cells-Is It Real?

PubMed

Vadasz, Zahava; Toubi, Elias

2017-06-01

During the last decade, B regulatory cells are appreciated to have a central role in preventing autoimmunity and maintaining self-tolerance. They are characterized by expressing different phenotypic markers and the production of either IL-10 or TGF-β or both. The recent recognition of Fas ligand expressing B regulatory cells as "killer" cells established their role in maintaining viral persistence by preventing effective antiviral immune responses. The forkhead lineage-transcription factor (FoxP3) was considered for many years to be a highly specific intracellular regulatory marker of CD4+CD25+ T regulatory cells. The possibility of FoxP3 being expressed in B regulatory cells was suggested in many studies. Though controversial, FoxP3 expression was also reported in macrophages and cancer cells. Aiming to avoid artifact staining, many researchers required the usage of FoxP3 messenger RNA (mRNA) and PCR in order to prove a true expression of FoxP3 in these different cells. In addition, most studies' report on that FoxP3 expression in all abovementioned cells is related to their status of activation since naïve (non-activated cells) were found poorly FoxP3 expressing. In this review, we present the existing data on FoxP3 expression in non-T-regulatory cells, but we suggest that further studies are needed to better establish this concept.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bin, Geng; Bo, Zhang; Jing, Wang

TNF-α is known to induce osteoblasts apoptosis, whereas mechanical stimulation has been shown to enhance osteoblast survival. In the present study, we found that mechanical stimulation in the form of fluid shear stress (FSS) suppresses TNF-α induced apoptosis in MC3T3-E1 cells. Extracellular signal-regulated kinase 5 (ERK5) is a member of the mitogen-activated protein kinase (MAPK) family that has been implicated in cell survival. We also demonstrated that FSS imposed by flow chamber in vitro leads to a markedly activation of ERK5, which was shown to be protective against TNF-α-induced apoptosis, whereas the transfection of siRNA against ERK5 (ERK5-siRNA) reversed themore » FSS-medicated anti-apoptotic effects. An initial FSS-mediated activation of ERK5 that phosphorylates AKT to increase its activity, and a following forkhead box O 3a (FoxO3a) was phosphorylated by activated AKT. Phosphorylated FoxO3a is sequestered in the cytoplasm, and prevents it from translocating to nucleus where it can increase the expression of FasL and Bim. The inhibition of AKT-FoxO3a signalings by a PI3K (PI3-kinase)/AKT inhibitor (LY294002) or the transfection of ERK5-siRNA led to the nuclear translocation of non-phosphorylated FoxO3a, and increased the protein expression of FasL and Bim. In addition, the activation of caspase-3 by TNF-α was significantly inhibited by aforementioned FSS-medicated mechanisms. In brief, the activation of ERK5-AKT-FoxO3a signaling pathways by FSS resulted in a decreased expression of FasL and Bim and an inhibition of caspase-3 activation, which exerts a protective effect that prevents osteoblasts from apoptosis. - Highlights: • Fluid shear stress inhibits osteoblast apoptosis induced by TNF-α. • Inhibition of ERK5 activity by transfection of ERK5 siRNA blocks FSS-mediated anti-apoptotic effect in osteoblast. • Activated ERK5-AKT-FoxO3a-Bim/FasL signaling pathways by FSS is required to protect osteoblast from apoptosis.« less

Different expression of FoxM1 in human benign and malignant pleural effusion.

PubMed

Tang, Zhonghao; Li, Hongqing; Zhu, Huili; Bai, Chunxue

2015-01-01

The aims of this study were as follows: to analyze the forkhead box M1 (FoxM1) expression in benign and malignant pleural effusion by reverse transcription-polymerase chain reaction assay (RT-PCR); to explore the role of FoxM1 in formation and progress in malignant pleural effusion, and whether there is significant difference in expression level of FoxM1 between benign and malignant pleural effusion; to seek a gene marker diagnostically useful to identify benign and malignant pleural effusion in diagnosis and treatment of pleural effusion; and to collect expression level data of FoxM1 in 23 malignant pleural effusion samples (17 adenocarcinoma samples, four squamous carcinoma samples and two small cell lung carcinoma samples) and 15 benign pleural effusion samples (11 inflammatory pleural effusions, two transudates, two tuberculous pleural effusions) by RT-PCR. Among all 38 samples, average FoxM1 expression level of benign pleural effusions is (235.09 ± 59.99), while malignant pleural effusions (828.77 ± 109.76). Among 23 malignant samples, average FoxM1 expression level is (529.27 ± 75.85) in samples without cytological diagnostic evidence, while (1,218.12 ± 167.21) in samples with cytological diagnostic evidence. Differences of FoxM1 expression level between benign pleural effusions and malignant ones have statistical significance. There is an area of 0.881 under the receiver-operating characteristic curve, which verifies the accuracy of using FoxM1 expression level as diagnostic index to identify benign and malignant pleural effusions. According to our study, diagnostic sensitivity and specificity for FoxM1 expression level at 418.1 were 82.6 and 86.7 %, respectively, while 47.8 and 100 %, respectively, at 768.7. FoxM1 expression level in malignant pleural effusions is significantly higher than in benign ones. This study provides a new approach in clinical diagnosis, with FoxM1 as a specific molecule marker to identify benign and malignant pleural effusions. FoxM1 expression level could provide evidence for diagnosis and treatment of malignant pleural effusions and lung cancer.

MicroRNA expression and protein acetylation pattern in respiratory and limb muscles of Parp-1(-/-) and Parp-2(-/-) mice with lung cancer cachexia.

PubMed

Chacon-Cabrera, Alba; Fermoselle, Clara; Salmela, Ida; Yelamos, Jose; Barreiro, Esther

2015-12-01

Current treatment options for cachexia, which impairs disease prognosis, are limited. Muscle-enriched microRNAs and protein acetylation are involved in muscle wasting including lung cancer (LC) cachexia. Poly(ADP-ribose) polymerases (PARP) are involved in muscle metabolism. We hypothesized that muscle-enriched microRNA, protein hyperacetylation, and expression levels of myogenic transcription factors (MTFs) and downstream targets, muscle loss and function improve in LC cachectic Parp-1(−/−) and Parp-2(−/−) mice. Body and muscle weights, grip strength, muscle phenotype, muscle-enriched microRNAs (miR-1, -133, -206, and -486), protein acetylation, acetylated levels of FoxO1, FoxO3, and PGC-1α, histone deacetylases (HDACs) including SIRT1, MTFs, and downstream targets (α-actin, PGC-1α, and creatine kinase) were evaluated in diaphragm and gastrocnemius of LC (LP07 adenocarcinoma) wild type (WT), Parp-1(−/−) and Parp-2−/− mice. Compared to WT cachectic animals, in both respiratory and limb muscles of Parp-1(−/−) and Parp-2(−/−) cachectic mice: downregulation of muscle-specific microRNAs was counterbalanced especially in gastrocnemius of Parp-1(−/−) mice; increased protein acetylation was attenuated (improvement in HDAC3, SIRT-1, and acetylated FoxO3 levels in both muscles, acetylated FoxO1 levels in the diaphragm); reduced MTFs and creatine kinase levels were mitigated; body and muscle weights, strength, and muscle fiber sizes improved, while tumor weight and growth decreased. These molecular findings may explain the improvements seen in body and muscle weights, limb muscle force and fiber sizes in both Parp-1(−/−) and Parp-2(−/−) cachectic mice. PARP-1 and -2 play a role in cancer-induced cachexia, thus selective pharmacological inhibition of PARP-1 and -2 may be of interest in clinical settings. Copyright © 2015 Elsevier B.V. All rights reserved.

Silibinin-induced glioma cell apoptosis by PI3K-mediated but Akt-independent downregulation of FoxM1 expression.

PubMed

Zhang, Mingjie; Liu, Yunhui; Gao, Yun; Li, Shaoyi

2015-10-15

The oncogenic transcription factor Forkhead box M1 (FoxM1) is overexpressed in many human tumors, including glioma. As a critical regulator of the cell cycle and apoptosis-related genes, FoxM1 is a potential therapeutic target against human malignant glioma. Silibinin, a flavonoid isolated from Silybum marianum, dose-dependently reduced glioma cell proliferation, promoted apoptosis, and downregulated FoxM1 expression. Knockdown of FoxM1 by small hairpin RNA (shRNA) transfection also promoted glioma cell apoptosis and augmented the antiproliferative and pro-apoptotic properties of silibinin. Moreover, silibinin increased caspase-3 activation, upregulated pro-apoptotic Bax, and suppressed anti-apoptotic Bcl-2 expression, effects enhanced by FoxM1 knockdown. Silibinin treatment suppressed U87 cell PI3K phospho-activation, and simultaneous silibinin exposure, FoxM1 knockdown, and PI3K inhibition additively increased U87 cell apoptosis. Furthermore, PI3K inhibition reduced FoxM1 expression. Akt activity was also suppressed by FoxM1 downregulation but Akt inhibition did not alter FoxM1 expression. Thus, silibinin likely inhibited glioma cell proliferation and induced apoptosis through inactivation of PI3K and FoxM1, leading to activation of the mitochondrial apoptotic pathway. FoxM1 may be a novel target for chemotherapy against human glioma. Copyright © 2015 Elsevier B.V. All rights reserved.

Helios, and not FoxP3, is the marker of activated Tregs expressing GARP/LAP.

PubMed

Elkord, Eyad; Abd Al Samid, May; Chaudhary, Belal

2015-08-21

Regulatory T cells (Tregs) are key players of immune regulation/dysregulation both in physiological and pathophysiological settings. Despite significant advances in understanding Treg function, there is still a pressing need to define reliable and specific markers that can distinguish different Treg subpopulations. Herein we show for the first time that markers of activated Tregs [latency associated peptide (LAP) and glycoprotein A repetitions predominant (GARP, or LRRC32)] are expressed on CD4+FoxP3- T cells expressing Helios (FoxP3-Helios+) in the steady state. Following TCR activation, GARP/LAP are up-regulated on CD4+Helios+ T cells regardless of FoxP3 expression (FoxP3+/-Helios+). We show that CD4+GARP+/-LAP+ Tregs make IL-10 immunosuppressive cytokine but not IFN-γ effector cytokine. Further characterization of FoxP3/Helios subpopulations showed that FoxP3+Helios+ Tregs proliferate in vitro significantly less than FoxP3+Helios- Tregs upon TCR stimulation. Unlike FoxP3+Helios- Tregs, FoxP3+Helios+ Tregs secrete IL-10 but not IFN-γ or IL-2, confirming they are bona fide Tregs with immunosuppressive characteristics. Taken together, Helios, and not FoxP3, is the marker of activated Tregs expressing GARP/LAP, and FoxP3+Helios+ Tregs have more suppressive characteristics, compared with FoxP3+Helios- Tregs. Our work implies that therapeutic modalities for treating autoimmune and inflammatory diseases, allergies and graft rejection should be designed to induce and/or expand FoxP3+Helios+ Tregs, while therapies against cancers or infectious diseases should avoid such expansion/induction.

FoxO1 and HNF-4 Are Involved in Regulation of Hepatic Glucokinase Gene Expression by Resveratrol*

PubMed Central

Ganjam, Goutham Kumar; Dimova, Elitsa Y.; Unterman, Terry G.; Kietzmann, Thomas

2009-01-01

Resveratrol, a polyphenol derived from grapes, exerts important effects on glucose and lipid metabolism, yet detailed mechanisms mediating these effects remain unknown. The liver plays a central role in energy homeostasis, and glucokinase (GK) is a key enzyme involved in glucose utilization. Resveratrol activates SIRT1 (sirtuin 1), which promotes deacetylation of the forkhead transcription factor FoxO1. Previously, we reported that FoxO1 can suppress and that HNF-4 can stimulate GK expression in the liver. Here, we examined the role of FoxO1 and HNF-4 in mediating resveratrol effects on liver GK expression. Resveratrol suppressed hepatic GK expression in vivo and in isolated hepatocytes, and knocking down FoxO1 with shRNAs disrupted this effect. Reporter gene, gel shift, supershift assay, and chromatin immunoprecipitation studies show that FoxO1 binds to the GK promoter and that the interplay between FoxO1 and HNF-4 within the GK promoter is essential for mediating the effects of resveratrol. Resveratrol promotes deacetylation of FoxO1 and enhances its recruitment to the FoxO-binding element. Conversely, resveratrol suppresses recruitment of HNF-4 to its binding site, and knockdown of FoxO1 blocks this effect of resveratrol. Coprecipitation and chromatin immunoprecipitation studies show that resveratrol enhances interaction between FoxO1 and HNF-4, reduces binding of HNF-4 to its own site, and promotes its recruitment to the FoxO site in a FoxO1-dependent manner. These results provide the first evidence that resveratrol represses GK expression via FoxO1 and that the interaction between FoxO1 and HNF-4 contributes to these effects of resveratrol. PMID:19740748

FoxO1 and HNF-4 are involved in regulation of hepatic glucokinase gene expression by resveratrol.

PubMed

Ganjam, Goutham Kumar; Dimova, Elitsa Y; Unterman, Terry G; Kietzmann, Thomas

2009-11-06

Resveratrol, a polyphenol derived from grapes, exerts important effects on glucose and lipid metabolism, yet detailed mechanisms mediating these effects remain unknown. The liver plays a central role in energy homeostasis, and glucokinase (GK) is a key enzyme involved in glucose utilization. Resveratrol activates SIRT1 (sirtuin 1), which promotes deacetylation of the forkhead transcription factor FoxO1. Previously, we reported that FoxO1 can suppress and that HNF-4 can stimulate GK expression in the liver. Here, we examined the role of FoxO1 and HNF-4 in mediating resveratrol effects on liver GK expression. Resveratrol suppressed hepatic GK expression in vivo and in isolated hepatocytes, and knocking down FoxO1 with shRNAs disrupted this effect. Reporter gene, gel shift, supershift assay, and chromatin immunoprecipitation studies show that FoxO1 binds to the GK promoter and that the interplay between FoxO1 and HNF-4 within the GK promoter is essential for mediating the effects of resveratrol. Resveratrol promotes deacetylation of FoxO1 and enhances its recruitment to the FoxO-binding element. Conversely, resveratrol suppresses recruitment of HNF-4 to its binding site, and knockdown of FoxO1 blocks this effect of resveratrol. Coprecipitation and chromatin immunoprecipitation studies show that resveratrol enhances interaction between FoxO1 and HNF-4, reduces binding of HNF-4 to its own site, and promotes its recruitment to the FoxO site in a FoxO1-dependent manner. These results provide the first evidence that resveratrol represses GK expression via FoxO1 and that the interaction between FoxO1 and HNF-4 contributes to these effects of resveratrol.

Cell type-specific expression of FoxP2 in the ferret and mouse retina.

PubMed

Sato, Chihiro; Iwai-Takekoshi, Lena; Ichikawa, Yoshie; Kawasaki, Hiroshi

2017-04-01

Although the anatomical and physiological properties of subtypes of retinal ganglion cells (RGCs) have been extensively investigated, their molecular properties are still unclear. Here, we examined the expression patterns of FoxP2 in the retina of ferrets and mice. We found that FoxP2 was expressed in small subsets of neurons in the adult ferret retina. FoxP2-positive neurons in the ganglion cell layer were divided into two groups. Large FoxP2-positive neurons expressed Brn3a and were retrogradely labeled with cholera toxin subunit B injected into the optic nerve, indicating that they are RGCs. The soma size and the projection pattern of FoxP2-positive RGCs were consistent with those of X cells. Because we previously reported that FoxP2 was selectively expressed in X cells in the ferret lateral geniculate nucleus (LGN), our findings indicate that FoxP2 is specifically expressed in the parvocellular pathway from the retina to the LGN. Small FoxP2-positive neurons were positive for GAD65/67, suggesting that they are GABAergic amacrine cells. Most Foxp2-positive cells were RGCs in the adult mouse retina. Dendritic morphological analyses suggested that Foxp2-positive RGCs included direction-selective RGCs in mice. Thus, our findings suggest that FoxP2 is expressed in specific subtypes of RGCs in the retina of ferrets and mice. Copyright © 2016 Elsevier Ireland Ltd and Japan Neuroscience Society. All rights reserved.

FoxP in bees: A comparative study on the developmental and adult expression pattern in three bee species considering isoforms and circuitry.

PubMed

Schatton, Adriana; Mendoza, Ezequiel; Grube, Kathrin; Scharff, Constance

2018-06-15

Mutations in the transcription factors FOXP1, FOXP2, and FOXP4 affect human cognition, including language. The FoxP gene locus is evolutionarily ancient and highly conserved in its DNA-binding domain. In Drosophila melanogaster FoxP has been implicated in courtship behavior, decision making, and specific types of motor-learning. Because honeybees (Apis mellifera, Am) excel at navigation and symbolic dance communication, they are a particularly suitable insect species to investigate a potential link between neural FoxP expression and cognition. We characterized two AmFoxP isoforms and mapped their expression in the brain during development and in adult foragers. Using a custom-made antiserum and in situ hybridization, we describe 11 AmFoxP expressing neuron populations. FoxP was expressed in equivalent patterns in two other representatives of Apidae; a closely related dwarf bee and a bumblebee species. Neural tracing revealed that the largest FoxP expressing neuron cluster in honeybees projects into a posterior tract that connects the optic lobe to the posterior lateral protocerebrum, predicting a function in visual processing. Our data provide an entry point for future experiments assessing the function of FoxP in eusocial Hymenoptera. © 2018 Wiley Periodicals, Inc.

Zebrafish foxP2 Zinc Finger Nuclease Mutant Has Normal Axon Pathfinding

PubMed Central

Xing, Lingyan; Hoshijima, Kazuyuki; Grunwald, David J.; Fujimoto, Esther; Quist, Tyler S.; Sneddon, Jacob; Chien, Chi-Bin; Stevenson, Tamara J.; Bonkowsky, Joshua L.

2012-01-01

foxP2, a forkhead-domain transcription factor, is critical for speech and language development in humans, but its role in the establishment of CNS connectivity is unclear. While in vitro studies have identified axon guidance molecules as targets of foxP2 regulation, and cell culture assays suggest a role for foxP2 in neurite outgrowth, in vivo studies have been lacking regarding a role for foxP2 in axon pathfinding. We used a modified zinc finger nuclease methodology to generate mutations in the zebrafish foxP2 gene. Using PCR-based high resolution melt curve analysis (HRMA) of G0 founder animals, we screened and identified three mutants carrying nonsense mutations in the 2nd coding exon: a 17 base-pair (bp) deletion, an 8bp deletion, and a 4bp insertion. Sequence analysis of cDNA confirmed that these were frameshift mutations with predicted early protein truncations. Homozygous mutant fish were viable and fertile, with unchanged body morphology, and no apparent differences in CNS apoptosis, proliferation, or patterning at embryonic stages. There was a reduction in expression of the known foxP2 target gene cntnap2 that was rescued by injection of wild-type foxP2 transcript. When we examined axon pathfinding using a pan-axonal marker or transgenic lines, including a foxP2-neuron-specific enhancer, we did not observe any axon guidance errors. Our findings suggest that foxP2 is not necessary for axon pathfinding during development. PMID:22937139

Zebrafish foxP2 zinc finger nuclease mutant has normal axon pathfinding.

PubMed

Xing, Lingyan; Hoshijima, Kazuyuki; Grunwald, David J; Fujimoto, Esther; Quist, Tyler S; Sneddon, Jacob; Chien, Chi-Bin; Stevenson, Tamara J; Bonkowsky, Joshua L

2012-01-01

foxP2, a forkhead-domain transcription factor, is critical for speech and language development in humans, but its role in the establishment of CNS connectivity is unclear. While in vitro studies have identified axon guidance molecules as targets of foxP2 regulation, and cell culture assays suggest a role for foxP2 in neurite outgrowth, in vivo studies have been lacking regarding a role for foxP2 in axon pathfinding. We used a modified zinc finger nuclease methodology to generate mutations in the zebrafish foxP2 gene. Using PCR-based high resolution melt curve analysis (HRMA) of G0 founder animals, we screened and identified three mutants carrying nonsense mutations in the 2(nd) coding exon: a 17 base-pair (bp) deletion, an 8bp deletion, and a 4bp insertion. Sequence analysis of cDNA confirmed that these were frameshift mutations with predicted early protein truncations. Homozygous mutant fish were viable and fertile, with unchanged body morphology, and no apparent differences in CNS apoptosis, proliferation, or patterning at embryonic stages. There was a reduction in expression of the known foxP2 target gene cntnap2 that was rescued by injection of wild-type foxP2 transcript. When we examined axon pathfinding using a pan-axonal marker or transgenic lines, including a foxP2-neuron-specific enhancer, we did not observe any axon guidance errors. Our findings suggest that foxP2 is not necessary for axon pathfinding during development.

FoxO Transcription Factors and Regenerative Pathways in Diabetes Mellitus

PubMed Central

Maiese, Kenneth

2015-01-01

Mammalian forkhead transcription factors of the O class (FoxO) are exciting targets under consideration for the development of new clinical entities to treat metabolic disorders and diabetes mellitus (DM). DM, a disorder that currently affects greater than 350 million individuals globally, can become a devastating disease that leads to cellular injury through oxidative stress pathways and affects multiple systems of the body. FoxO proteins can regulate insulin signaling, gluconeogenesis, insulin resistance, immune cell migration, and cell senescence. FoxO proteins also control cell fate through oxidative stress and pathways of autophagy and apoptosis that either lead to tissue regeneration or cell demise. Furthermore, FoxO signaling can be dependent upon signal transduction pathways that include silent mating type information regulation 2 homolog 1 (S. cerevisiae) (SIRT1), Wnt, and Wnt1 inducible signaling pathway protein 1 (WISP1). Cellular metabolic pathways driven by FoxO proteins are complex, can lead to variable clinical outcomes, and require in-depth analysis of the epigenetic and post-translation protein modifications that drive FoxO protein activation and degradation. PMID:26256004

Helios, and not FoxP3, is the marker of activated Tregs expressing GARP/LAP

PubMed Central

Elkord, Eyad; Abd Al Samid, May; Chaudhary, Belal

2015-01-01

Regulatory T cells (Tregs) are key players of immune regulation/dysregulation both in physiological and pathophysiological settings. Despite significant advances in understanding Treg function, there is still a pressing need to define reliable and specific markers that can distinguish different Treg subpopulations. Herein we show for the first time that markers of activated Tregs [latency associated peptide (LAP) and glycoprotein A repetitions predominant (GARP, or LRRC32)] are expressed on CD4+FoxP3− T cells expressing Helios (FoxP3−Helios+) in the steady state. Following TCR activation, GARP/LAP are up-regulated on CD4+Helios+ T cells regardless of FoxP3 expression (FoxP3+/−Helios+). We show that CD4+GARP+/−LAP+ Tregs make IL-10 immunosuppressive cytokine but not IFN-γ effector cytokine. Further characterization of FoxP3/Helios subpopulations showed that FoxP3+Helios+ Tregs proliferate in vitro significantly less than FoxP3+Helios− Tregs upon TCR stimulation. Unlike FoxP3+Helios− Tregs, FoxP3+Helios+ Tregs secrete IL-10 but not IFN-γ or IL-2, confirming they are bona fide Tregs with immunosuppressive characteristics. Taken together, Helios, and not FoxP3, is the marker of activated Tregs expressing GARP/LAP, and FoxP3+Helios+ Tregs have more suppressive characteristics, compared with FoxP3+Helios− Tregs. Our work implies that therapeutic modalities for treating autoimmune and inflammatory diseases, allergies and graft rejection should be designed to induce and/or expand FoxP3+Helios+ Tregs, while therapies against cancers or infectious diseases should avoid such expansion/induction. PMID:26343373

[Establishment and application of a Vero cell line stably expressing raccoon dog SLAM, the cellular receptor of canine distemper virus].

PubMed

Zhao, Jianjun; Yan, Ruxun; Zhang, Hailing; Zhang, Lei; Hu, Bo; Bai, Xue; Shao, Xiqun; Chai, Xiuli; Yan, Xijun; Wu, Wei

2012-12-04

The signaling lymphocyte activation molecule (SLAM, also known as CD150), is used as a cellular receptor by canine distemper virus (CDV). Wild-type strains of CDVs can be isolated and propagated efficiently in non-lymphoid cells expressing this protein. Our aim is to establish a Vero cells expressing raccoon dog SLAM (rSLAM) to efficiently isolate CDV from pathological samples. A eukaryotic expression plasmid, pIRES2-EGFP-rSLAMhis, containing rSLAM gene fused with six histidine-coding sequence, EGFP gene, and neomycin resistance gene was constructed. After transfection with the plasmid, a stable cell line, Vero-rSLAM, was screened from Vero cells with the identification of EGFP reporter and G418 resistance. Three CD positive specimens from infected foxes and raccoon dogs were inoculated to Vero-rSLAM cells for CDV isolation. Foxes and raccoon dogs were inoculated subcutaneously LN (10)fl strain with 4 x 10(2.39)TCID50 dose to evaluate pathogenicity of CDV isolations. The rSLAMh fused gene was shown to transcript and express stably in Vero-rSLAM cells by RT-PCR and Immunohistochemistry assay. Three CDV strains were isolated successfully in Vero-rSLAM cells 36 -48 hours after inoculation with spleen or lung specimens from foxes and raccoon dogs with distemper. By contrast, no CDV was recovered from those CD positive specimens when Vero cells were used for virus isolation. Infected foxes and raccoon dogs with LN(10)f1 strain all showed typical CD symptoms and high mortality (2/3 for foxes and 3/3 for raccoon dogs) in 22 days post challenge. Our results indicate that Vero-rSLAM cells stably expressing raccoon dog SLAM are highly sensitive to CDV in clinical specimens and the CDV isolation can maintain high virulence to its host animals.

Effects of miR-155 on proliferation and apoptosis by regulating FoxO3a/BIM in liver cancer cell line HCCLM3.

PubMed

Liao, W-W; Zhang, C; Liu, F-R; Wang, W-J

2018-03-01

MiR-155 has been shown to be up-regulated in hepatocellular carcinoma (HCC) patients. B-cell lymphoma-2 (Bcl-2) interacting mediator of cell death (BIM) regulates cell proliferation and apoptosis, as its down-regulation is involved in HCC onset. Transcriptional factor FoxO3a mediates BIM expression and is related to HCC pathogenesis. Bioinformatics analysis showed targeted regulation of FoxO3a by miR-155. This study aims to investigate whether miR-155 plays a role in mediating FoxO3a/BIM signal pathway and HCC occurrence. HCC patients were collected for tumor and adjacent tissues, in which microRNA-155 (miR-155) and FoxO3a expressions were examined. In vitro cultured HCCLM3, HepG2 and L-02 cells were tested for basal apoptotic rate by flow cytometry and were compared for miR-155 and FoxO3a expression. Dual-luciferase reporter gene assay demonstrated the targeted relationship between miR-155 and FoxO3a. HCCLM3 cells were treated with miR-155 inhibitor and/or FoxO3a-pMD18-T. Cell apoptosis and proliferation were examined by using flow cytometry and MTT assays, respectively. Western blot and spectrometry assay were employed to quantify the FoxO3a, BIM expressions, and caspase activity. Compared to adjacent tissues, HCC tissues had significantly higher miR-155 and significantly lower FoxO3a expression (p<0.05). HCCLM3 and HepG2 cells had significantly lower FoxO3a expression and basal apoptotic rate compared to L02 cells, whilst miR-155 level was significantly higher (p<0.05). MiR-155 targeted and inhibited 3'-UTR of FoxO3a, increasing BIM expression, caspase-3, and caspase-9 activities, and enhancing cell apoptosis and weakening proliferation. HCC tissues elevated the miR-155 and suppressed the FoxO3a expressions. MiR-155 targeted and inhibited FoxO3a expression to suppress the BIM, depress caspase-3 and caspase-9 activities, therefore inhibiting the HCC cell apoptosis and facilitating proliferation.

Expression of fox-related genes in the skin follicles of Inner Mongolia cashmere goat.

PubMed

Han, Wenjing; Li, Xiaoyan; Wang, Lele; Wang, Honghao; Yang, Kun; Wang, Zhixin; Wang, Ruijun; Su, Rui; Liu, Zhihong; Zhao, Yanhong; Zhang, Yanjun; Li, Jinquan

2018-03-01

This study investigated the expression of genes in cashmere goats at different periods of their fetal development. Bioinformatics analysis was used to evaluate data obtained by transcriptome sequencing of fetus skin samples collected from Inner Mongolia cashmere goats on days 45, 55, and 65 of fetal age. We found that FoxN1 , FoxE1 , and FoxI3 genes of the Fox gene family were probably involved in the growth and development of the follicle and the formation of hair, which is consistent with previous findings. Real-time quantitative polymerase chain reaction detecting system and Western blot analysis were employed to study the relative differentially expressed genes FoxN1 , FoxE1 , and FoxI3 in the body skin of cashmere goat fetuses and adult individuals. This study provided new fundamental information for further investigation of the genes related to follicle development and exploration of their roles in hair follicle initiation, growth, and development.

Differential Regulation of Hippocampal IGF-1-Associated Signaling Proteins by Dietary Restriction in Aging Mouse.

PubMed

Hadem, Ibanylla Kynjai Hynniewta; Sharma, Ramesh

2017-08-01

Time-dependent alterations in several biological processes of an organism may be characterized as aging. One of the effects of aging is the decline in cognitive functions. Dietary restriction (DR), an intervention where the consumption of food is lessened but without malnutrition, is a well-established mechanism that has a wide range of important outcomes including improved health span, delayed aging, and extension of lifespan of various species. It also plays a beneficial role in protecting against age-dependent deterioration of cognitive functions, and has neuroprotective properties against neurodegenerative diseases. Insulin-like growth factor (IGF)-1 plays an important role in the regulation of cellular and tissue functions, and relating to the aging process the most important pathway of IGF-1 is the phosphatidylinositol 3-kinase (PI3K) and protein kinase B (Akt/PKB) signaling cascade. Although many have studied the changes in the level of IGF-1 and its effect on neural proliferation, the downstream signaling proteins have not been fully elucidated. Hence in the present investigation, the IGF-1 gene expression and the normal endogenous levels of IGF1R (IGF-1 receptor), PI3K, Akt, pAkt, and pFoxO in the hippocampus of young, adult, and old mice were determined using real-time PCR and Western blot analyses. The effects of DR on these protein levels were also studied. Results showed a decrease in the levels of IGF-1, IGF1R, PI3K, and pAkt, while pFoxO level increased with respect to age. Under DR, these protein levels are maintained in adult mice, but old mice displayed diminished expression levels of these proteins as compared to ad libitum-fed mice. Maintenance of PI3K/Akt pathway results in the phosphorylation of FoxOs, necessary for the enhancement of neural proliferation and survival in adult mice. The down-regulation of IGF-I signaling, as observed in old mice, leads to increasing the activity of FoxO factors that may be important for the neuroprotective effects seen with DR.

An amphioxus winged helix/forkhead gene, AmphiFoxD: insights into vertebrate neural crest evolution

NASA Technical Reports Server (NTRS)

Yu, Jr-Kai; Holland, Nicholas D.; Holland, Linda Z.

2002-01-01

During amphioxus development, the neural plate is bordered by cells expressing many genes with homologs involved in vertebrate neural crest induction. However, these amphioxus cells evidently lack additional genetic programs for the cell delaminations, migrations, and differentiations characterizing definitive vertebrate neural crest. We characterize an amphioxus winged helix/forkhead gene (AmphiFoxD) closely related to vertebrate FoxD genes. Phylogenetic analysis indicates that the AmphiFoxD is basal to vertebrate FoxD1, FoxD2, FoxD3, FoxD4, and FoxD5. One of these vertebrate genes (FoxD3) consistently marks neural crest during development. Early in amphioxus development, AmphiFoxD is expressed medially in the anterior neural plate as well as in axial (notochordal) and paraxial mesoderm; later, the gene is expressed in the somites, notochord, cerebral vesicle (diencephalon), and hindgut endoderm. However, there is never any expression in cells bordering the neural plate. We speculate that an AmphiFoxD homolog in the common ancestor of amphioxus and vertebrates was involved in histogenic processes in the mesoderm (evagination and delamination of the somites and notochord); then, in the early vertebrates, descendant paralogs of this gene began functioning in the presumptive neural crest bordering the neural plate to help make possible the delaminations and cell migrations that characterize definitive vertebrate neural crest. Copyright 2002 Wiley-Liss, Inc.

Genome-wide identification, phylogeny, and gonadal expression of fox genes in Nile tilapia, Oreochromis niloticus.

PubMed

Yuan, Jing; Tao, Wenjing; Cheng, Yunying; Huang, Baofeng; Wang, Deshou

2014-08-01

The fox genes play important roles in various biological processes, including sexual development. In the present study, we isolated 65 fox genes, belonging to 18 subfamilies named A-R, from Nile tilapia through genome-wide screening. Twenty-four of them have two or three (foxm1) copies. Furthermore, 16, 25, 68, and 45 fox members were isolated from nematodes, protochordates, teleosts, and tetrapods, respectively. Phylogenetic analyses indicated fox gene family had undergone three expansions parallel to the three rounds of genome duplication during evolution. We also analyzed the clustered fox genes and found that apparent linkage duplication existed in teleosts, which further supported fish-specific genome duplication hypothesis. In addition, species- and lineage-specific duplication is another reason for fox gene family expansion. Based on the four pairs of XX and XY gonadal transcriptome data from four critical developmental stages, we analyzed the expression profile of all fox genes and identified sexually dimorphic fox genes at each stage. All fox genes were detected in gonads, with 15 of them at the background expression level (total read per kb per million reads, RPKM < 10), 29 at moderate expression level (10 < total RPKM < 100), and 21 at high expression level (total RPKM > 100). There are 27, 24, 28, and 9 sexually dimorphic fox genes at 5, 30, 90, and 180 days after hatching (dah), respectively. foxq1a, foxf1, foxr1, and foxr1 were identified as the most differentially expressed genes at each stage. foxl2 was characterized as XX-dominant gene, while foxd5, foxi3, foxn3, foxj1a, foxj3b, and foxo6b were characterized as XY-dominant genes. qPCR and in situ hybridization of foxh1 and foxj1a were performed to confirm the expression profiles and to validate the transcriptome data. Our results suggest that fox genes might play important roles in sex determination and gonadal development in teleosts.

Transcription Factor FoxO1 Is Essential for Enamel Biomineralization

PubMed Central

Poché, Ross A.; Sharma, Ramaswamy; Garcia, Monica D.; Wada, Aya M.; Nolte, Mark J.; Udan, Ryan S.; Paik, Ji-Hye; DePinho, Ronald A.; Bartlett, John D.; Dickinson, Mary E.

2012-01-01

The Transforming growth factor β (Tgf-β) pathway, by signaling via the activation of Smad transcription factors, induces the expression of many diverse downstream target genes thereby regulating a vast array of cellular events essential for proper development and homeostasis. In order for a specific cell type to properly interpret the Tgf-β signal and elicit a specific cellular response, cell-specific transcriptional co-factors often cooperate with the Smads to activate a discrete set of genes in the appropriate temporal and spatial manner. Here, via a conditional knockout approach, we show that mice mutant for Forkhead Box O transcription factor FoxO1 exhibit an enamel hypomaturation defect which phenocopies that of the Smad3 mutant mice. Furthermore, we determined that both the FoxO1 and Smad3 mutant teeth exhibit changes in the expression of similar cohort of genes encoding enamel matrix proteins required for proper enamel development. These data raise the possibility that FoxO1 and Smad3 act in concert to regulate a common repertoire of genes necessary for complete enamel maturation. This study is the first to define an essential role for the FoxO family of transcription factors in tooth development and provides a new molecular entry point which will allow researchers to delineate novel genetic pathways regulating the process of biomineralization which may also have significance for studies of human tooth diseases such as amelogenesis imperfecta. PMID:22291941

The ins and outs of FoxO shuttling: mechanisms of FoxO translocation and transcriptional regulation.

PubMed Central

Van Der Heide, Lars P; Hoekman, Marco F M; Smidt, Marten P

2004-01-01

FoxO (forkhead box O; forkhead members of the O class) are transcription factors that function under the control of insulin/insulin-like signalling. FoxO factors have been associated with a multitude of biological processes, including cell-cycle, cell death, DNA repair, metabolism and protection from oxidative stress. Central to the regulation of FoxO factors is a shuttling system, which confines FoxO factors to either the nucleus or the cytosol. Shuttling of FoxO requires protein phosphorylation within several domains, and association with 14-3-3 proteins and the nuclear transport machinery. Description of the FoxO-shuttling mechanism contributes to the understanding of FoxO function in relation to signalling and gene regulation. PMID:15005655

Mitochondrial Hormesis links nutrient restriction to improved metabolism in fat cell.

PubMed

Lettieri Barbato, Daniele; Tatulli, Giuseppe; Aquilano, Katia; Ciriolo, Maria R

2015-10-01

Fasting promotes longevity by reprogramming metabolic and stress resistance pathways. However, although the impact on adipose tissue physiology through hormonal inputs is well established, the direct role of fasting on adipose cells is poorly understood. Herein we show that white and beige adipocytes, as well as mouse epididymal and subcutaneous adipose depots, respond to nutrient scarcity by acquiring a brown-like phenotype. Indeed, they improve oxidative metabolism through modulating the expression of mitochondrial- and nuclear-encoded oxidative phosphorylation genes as well as mitochondrial stress defensive proteins (UCP1, SOD2). Such adaptation is placed in a canonical mitohormetic response that proceeds via mitochondrial reactive oxygen species ((mt)ROS) production and redistribution of FoxO1 transcription factor into nucleus. Nuclear FoxO1 ((n)FoxO1) mediates retrograde communication by inducing the expression of mitochondrial oxidative and stress defensive genes. Collectively, our findings describe an unusual white/beige fat cell response to nutrient availability highlighting another health-promoting mechanism of fasting.

FoxO inhibits juvenile hormone biosynthesis and vitellogenin production in the German cockroach.

PubMed

Süren-Castillo, Songül; Abrisqueta, Marc; Maestro, José L

2012-07-01

The transcription factor Forkhead-box O (FoxO) is the main transcriptional effector of the Insulin Receptor/Phosphatidylinositol 3-kinase (InR/PI3K) pathway. In a situation of nutrient restriction, the pathway is inactive and FoxO translocates to the nucleus to exert its transcriptional action. In starved females of the cockroach Blattella germanica, the reproductive processes, and in particular the synthesis of juvenile hormone in the corpora allata and that of vitellogenin in the fat body, are arrested. In the present report we examine the possible role of FoxO in the transduction of the nutritional signals to these reproductive events. We first cloned FoxO cDNA from B. germanica (BgFoxO), and showed that its expression is not nutritionally regulated. BgFoxO knockdown using systemic RNAi in vivo in starved females elicited an increase of juvenile hormone biosynthesis, although without modifying mRNA levels of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) synthase-1, HMG-CoA synthase-2, HMG-CoA reductase or methyl farnesoate epoxidase (CYP15A1) in corpora allata. In addition, BgFoxO RNAi treatment produced a remarkable increase of vitellogenin mRNA levels in fat body and of vitellogenin protein in the haemolymph. Our results indicate that BgFoxO plays an inhibitory role on juvenile hormone biosynthesis and vitellogenin production in a situation of nutrient shortage. Copyright © 2012 Elsevier Ltd. All rights reserved.

FoxA family members are crucial regulators of the hypertrophic chondrocyte differentiation program

PubMed Central

Ionescu, Andreia; Kozhemyakina, Elena; Nicolae, Claudia; Kaestner, Klaus H.; Olsen, Bjorn R.; Lassar, Andrew B.

2012-01-01

During endochondral ossification small immature chondrocytes enlarge to form hypertrophic chondrocytes, which express collagen X. In this work, we demonstrate that FoxA factors are induced during chondrogenesis, bind to conserved binding sites in the collagen X enhancer, and can promote the expression of a collagen X-luciferase reporter in both chondrocytes and fibroblasts. In addition, we demonstrate by both gain and loss of function analyses that FoxA factors play a crucial role driving the expression of both endogenous collagen X and other hypertrophic chondrocyte-specific genes. Mice engineered to lack expression of both FoxA2 and FoxA3 in their chondrocytes display defects in chondrocyte hypertrophy, alkaline phosphatase expression, and mineralization in their sternebrae and in addition exhibit postnatal dwarfism that is coupled to significantly decreased expression of both collagen X and MMP13 in their growth plates. Together, our findings indicate that FoxA family members are crucial regulators of the hypertrophic chondrocyte differentiation program. PMID:22595668

Farnesoid X receptor regulates forkhead Box O3a activation in ethanol-induced autophagy and hepatotoxicity

PubMed Central

Manley, Sharon; Ni, Hong-Min; Williams, Jessica A.; Kong, Bo; DiTacchio, Luciano; Guo, Grace; Ding, Wen-Xing

2014-01-01

Alcoholic liver disease encompasses a wide spectrum of pathogenesis including steatosis, fibrosis, cirrhosis, and alcoholic steatohepatitis. Autophagy is a lysosomal degradation process that degrades cellular proteins and damaged/excess organelles, and serves as a protective mechanism in response to various stresses. Acute alcohol treatment induces autophagy via FoxO3a-mediated autophagy gene expression and protects against alcohol-induced steatosis and liver injury in mice. Farnesoid X Receptor (FXR) is a nuclear receptor that regulates cellular bile acid homeostasis. In the present study, wild type and FXR knockout (KO) mice were treated with acute ethanol for 16 h. We found that ethanol treated-FXR KO mice had exacerbated hepatotoxicity and steatosis compared to wild type mice. Furthermore, we found that ethanol treatment had decreased expression of various essential autophagy genes and several other FoxO3 target genes in FXR KO mice compared with wild type mice. Mechanistically, we did not find a direct interaction between FXR and FoxO3. Ethanol-treated FXR KO mice had increased Akt activation, increased phosphorylation of FoxO3 resulting in decreased FoxO3a nuclear retention and DNA binding. Furthermore, ethanol treatment induced hepatic mitochondrial spheroid formation in FXR KO mice but not in wild type mice, which may serve as a compensatory alternative pathway to remove ethanol-induced damaged mitochondria in FXR KO mice. These results suggest that lack of FXR impaired FoxO3a-mediated autophagy and in turn exacerbated alcohol-induced liver injury. PMID:25460735

Genetic identity of thermosensory relay neurons in the lateral parabrachial nucleus.

PubMed

Geerling, Joel C; Kim, Minjee; Mahoney, Carrie E; Abbott, Stephen B G; Agostinelli, Lindsay J; Garfield, Alastair S; Krashes, Michael J; Lowell, Bradford B; Scammell, Thomas E

2016-01-01

The parabrachial nucleus is important for thermoregulation because it relays skin temperature information from the spinal cord to the hypothalamus. Prior work in rats localized thermosensory relay neurons to its lateral subdivision (LPB), but the genetic and neurochemical identity of these neurons remains unknown. To determine the identity of LPB thermosensory neurons, we exposed mice to a warm (36°C) or cool (4°C) ambient temperature. Each condition activated neurons in distinct LPB subregions that receive input from the spinal cord. Most c-Fos+ neurons in these LPB subregions expressed the transcription factor marker FoxP2. Consistent with prior evidence that LPB thermosensory relay neurons are glutamatergic, all FoxP2+ neurons in these subregions colocalized with green fluorescent protein (GFP) in reporter mice for Vglut2, but not for Vgat. Prodynorphin (Pdyn)-expressing neurons were identified using a GFP reporter mouse and formed a caudal subset of LPB FoxP2+ neurons, primarily in the dorsal lateral subnucleus (PBdL). Warm exposure activated many FoxP2+ neurons within PBdL. Half of the c-Fos+ neurons in PBdL were Pdyn+, and most of these project into the preoptic area. Cool exposure activated a separate FoxP2+ cluster of neurons in the far-rostral LPB, which we named the rostral-to-external lateral subnucleus (PBreL). These findings improve our understanding of LPB organization and reveal that Pdyn-IRES-Cre mice provide genetic access to warm-activated, FoxP2+ glutamatergic neurons in PBdL, many of which project to the hypothalamus.

Young and intense: FoxP2 immunoreactivity in Area X varies with age, song stereotypy, and singing in male zebra finches

PubMed Central

Thompson, Christopher K.; Schwabe, Fabian; Schoof, Alexander; Mendoza, Ezequiel; Gampe, Jutta; Rochefort, Christelle; Scharff, Constance

2013-01-01

FOXP2 is a transcription factor functionally relevant for learned vocalizations in humans and songbirds. In songbirds, FoxP2 mRNA expression in the medium spiny neurons of the basal ganglia song nucleus Area X is developmentally regulated and varies with singing conditions in different social contexts. How individual neurons in Area X change FoxP2 expression across development and in social contexts is not known, however. Here we address this critical gap in our understanding of FoxP2 as a link between neuronal networks and behavior. We used a statistically unbiased analysis of FoxP2-immunoreactivity (FoxP2-IR) on a neuron-by-neuron basis and found a bimodal distribution of FoxP2-IR neurons in Area X: weakly-stained and intensely-stained. The density of intensely-stained FoxP2-IR neurons was 10 times higher in juveniles than in adults, exponentially decreased with age, and was negatively correlated with adult song stability. Three-week old neurons labeled with BrdU were more than five times as likely to be intensely-stained than weakly-stained. The density of FoxP2-IR putative migratory neurons with fusiform-shaped nuclei substantially decreased as birds aged. The density of intensely-stained FoxP2-IR neurons was not affected by singing whereas the density of weakly-stained FoxP2-IR neurons was. Together, these data indicate that young Area X medium spiny neurons express FoxP2 at high levels and decrease expression as they become integrated into existing neural circuits. Once integrated, levels of FoxP2 expression correlate with singing behavior. Together, these findings raise the possibility that FoxP2 levels may orchestrate song learning and song stereotypy in adults by a common mechanism. PMID:23450800

Young and intense: FoxP2 immunoreactivity in Area X varies with age, song stereotypy, and singing in male zebra finches.

PubMed

Thompson, Christopher K; Schwabe, Fabian; Schoof, Alexander; Mendoza, Ezequiel; Gampe, Jutta; Rochefort, Christelle; Scharff, Constance

2013-01-01

FOXP2 is a transcription factor functionally relevant for learned vocalizations in humans and songbirds. In songbirds, FoxP2 mRNA expression in the medium spiny neurons of the basal ganglia song nucleus Area X is developmentally regulated and varies with singing conditions in different social contexts. How individual neurons in Area X change FoxP2 expression across development and in social contexts is not known, however. Here we address this critical gap in our understanding of FoxP2 as a link between neuronal networks and behavior. We used a statistically unbiased analysis of FoxP2-immunoreactivity (FoxP2-IR) on a neuron-by-neuron basis and found a bimodal distribution of FoxP2-IR neurons in Area X: weakly-stained and intensely-stained. The density of intensely-stained FoxP2-IR neurons was 10 times higher in juveniles than in adults, exponentially decreased with age, and was negatively correlated with adult song stability. Three-week old neurons labeled with BrdU were more than five times as likely to be intensely-stained than weakly-stained. The density of FoxP2-IR putative migratory neurons with fusiform-shaped nuclei substantially decreased as birds aged. The density of intensely-stained FoxP2-IR neurons was not affected by singing whereas the density of weakly-stained FoxP2-IR neurons was. Together, these data indicate that young Area X medium spiny neurons express FoxP2 at high levels and decrease expression as they become integrated into existing neural circuits. Once integrated, levels of FoxP2 expression correlate with singing behavior. Together, these findings raise the possibility that FoxP2 levels may orchestrate song learning and song stereotypy in adults by a common mechanism.

Changes in the expression of Fox O1 and death ligand genes during follicular atresia in porcine ovary.

PubMed

Lin, F; Fu, Y H; Han, J; Shen, M; Du, C W; Li, R; Ma, X S; Liu, H L

2014-08-28

Follicular atresia, a key phenomenon in follicle development, eliminates most of the follicles in mammalian ovaries. To investigate the molecular mechanism of follicular atresia in porcine ovaries, we investigated the mRNA expression of three important cell death ligand-receptor systems and Fox O1 in follicles with a diameter of 3-5 mm. The phosphorylation and subcellular localization of Fox O1 during granulosa cell apoptosis was also determined. TRAIL and Fas L played an important role in follicular atresia at this stage. Fox O1 expression was upregulated during atresia, and was confined to the nucleus of granulosa cells; however, phosphorylated Fox O1 was localized to the cytoplasm. These results suggest Fox O1 involvement in the regulation of TRAIL and Fas L expression during follicular atresia in pigs.

Non-viral FoxM1 gene delivery to hepatocytes enhances liver repopulation

PubMed Central

Xiang, D; Liu, C-C; Wang, M-J; Li, J-X; Chen, F; Yao, H; Yu, B; Lu, L; Borjigin, U; Chen, Y-X; Zhong, L; Wangensteen, K J; He, Z-Y; Wang, X; Hu, Y-P

2014-01-01

Hepatocyte transplantation as a substitute strategy of orthotopic liver transplantation is being studied for treating end-stage liver diseases. Several technical hurdles must be overcome in order to achieve the therapeutic liver repopulation, such as the problem of insufficient expansion of the transplanted hepatocytes in recipient livers. In this study, we analyzed the application of FoxM1, a cell-cycle regulator, to enhance the proliferation capacity of hepatocytes. The non-viral sleeping beauty (SB) transposon vector carrying FoxM1 gene was constructed for delivering FoxM1 into the hepatocytes. The proliferation capacities of hepatocytes with FoxM1 expression were examined both in vivo and in vitro. Results indicated that the hepatocytes with FoxM1 expression had a higher proliferation rate than wild-type (WT) hepatocytes in vitro. In comparison with WT hepatocytes, the hepatocytes with FoxM1 expression had an enhanced level of liver repopulation in the recipient livers at both sub-acute injury (fumaryl acetoacetate hydrolase (Fah)–/– mice model) and acute injury (2/3 partial hepatectomy mice model). Importantly, there was no increased risk of tumorigenicity with FoxM1 expression in recipients even after serial transplantation. In conclusion, expression of FoxM1 in hepatocytes enhanced the capacity of liver repopulation without inducing tumorigenesis. FoxM1 gene delivered by non-viral SB vector into hepatocytes may be a viable approach to promote therapeutic repopulation after hepatocyte transplantation. PMID:24853430

FoxO1 regulates myocardial glucose oxidation rates via transcriptional control of pyruvate dehydrogenase kinase 4 expression.

PubMed

Gopal, Keshav; Saleme, Bruno; Al Batran, Rami; Aburasayn, Hanin; Eshreif, Amina; Ho, Kim L; Ma, Wayne K; Almutairi, Malak; Eaton, Farah; Gandhi, Manoj; Park, Edwards A; Sutendra, Gopinath; Ussher, John R

2017-09-01

Pyruvate dehydrogenase (PDH) is the rate-limiting enzyme for glucose oxidation and a critical regulator of metabolic flexibility during the fasting to feeding transition. PDH is regulated via both PDH kinases (PDHK) and PDH phosphatases, which phosphorylate/inactivate and dephosphorylate/activate PDH, respectively. Our goal was to determine whether the transcription factor forkhead box O1 (FoxO1) regulates PDH activity and glucose oxidation in the heart via increasing the expression of Pdk4 , the gene encoding PDHK4. To address this question, we differentiated H9c2 myoblasts into cardiac myocytes and modulated FoxO1 activity, after which Pdk4 /PDHK4 expression and PDH phosphorylation/activity were assessed. We assessed binding of FoxO1 to the Pdk4 promoter in cardiac myocytes in conjunction with measuring the role of FoxO1 on glucose oxidation in the isolated working heart. Both pharmacological (1 µM AS1842856) and genetic (siRNA mediated) inhibition of FoxO1 decreased Pdk4 /PDHK4 expression and subsequent PDH phosphorylation in H9c2 cardiac myocytes, whereas 10 µM dexamethasone-induced Pdk4 /PDHK4 expression was abolished via pretreatment with 1 µM AS1842856. Furthermore, transfection of H9c2 cardiac myocytes with a vector expressing FoxO1 increased luciferase activity driven by a Pdk4 promoter construct containing the FoxO1 DNA-binding element region, but not in a Pdk4 promoter construct lacking this region. Finally, AS1842856 treatment in fasted mice enhanced glucose oxidation rates during aerobic isolated working heart perfusions. Taken together, FoxO1 directly regulates Pdk4 transcription in the heart, thereby controlling PDH activity and subsequent glucose oxidation rates. NEW & NOTEWORTHY Although studies have shown an association between FoxO1 activity and pyruvate dehydrogenase kinase 4 expression, our study demonstrated that pyruvate dehydrogenase kinase 4 is a direct transcriptional target of FoxO1 (but not FoxO3/FoxO4) in the heart. Furthermore, we report here, for the first time, that FoxO1 inhibition increases glucose oxidation in the isolated working mouse heart. Copyright © 2017 the American Physiological Society.

Sequence comparison of prefrontal cortical brain transcriptome from a tame and an aggressive silver fox (Vulpes vulpes).

PubMed

Kukekova, Anna V; Johnson, Jennifer L; Teiling, Clotilde; Li, Lewyn; Oskina, Irina N; Kharlamova, Anastasiya V; Gulevich, Rimma G; Padte, Ravee; Dubreuil, Michael M; Vladimirova, Anastasiya V; Shepeleva, Darya V; Shikhevich, Svetlana G; Sun, Qi; Ponnala, Lalit; Temnykh, Svetlana V; Trut, Lyudmila N; Acland, Gregory M

2011-10-03

Two strains of the silver fox (Vulpes vulpes), with markedly different behavioral phenotypes, have been developed by long-term selection for behavior. Foxes from the tame strain exhibit friendly behavior towards humans, paralleling the sociability of canine puppies, whereas foxes from the aggressive strain are defensive and exhibit aggression to humans. To understand the genetic differences underlying these behavioral phenotypes fox-specific genomic resources are needed. cDNA from mRNA from pre-frontal cortex of a tame and an aggressive fox was sequenced using the Roche 454 FLX Titanium platform (> 2.5 million reads & 0.9 Gbase of tame fox sequence; >3.3 million reads & 1.2 Gbase of aggressive fox sequence). Over 80% of the fox reads were assembled into contigs. Mapping fox reads against the fox transcriptome assembly and the dog genome identified over 30,000 high confidence fox-specific SNPs. Fox transcripts for approximately 14,000 genes were identified using SwissProt and the dog RefSeq databases. An at least 2-fold expression difference between the two samples (p < 0.05) was observed for 335 genes, fewer than 3% of the total number of genes identified in the fox transcriptome. Transcriptome sequencing significantly expanded genomic resources available for the fox, a species without a sequenced genome. In a very cost efficient manner this yielded a large number of fox-specific SNP markers for genetic studies and provided significant insights into the gene expression profile of the fox pre-frontal cortex; expression differences between the two fox samples; and a catalogue of potentially important gene-specific sequence variants. This result demonstrates the utility of this approach for developing genomic resources in species with limited genomic information.

Sequence comparison of prefrontal cortical brain transcriptome from a tame and an aggressive silver fox (Vulpes vulpes)

PubMed Central

2011-01-01

Background Two strains of the silver fox (Vulpes vulpes), with markedly different behavioral phenotypes, have been developed by long-term selection for behavior. Foxes from the tame strain exhibit friendly behavior towards humans, paralleling the sociability of canine puppies, whereas foxes from the aggressive strain are defensive and exhibit aggression to humans. To understand the genetic differences underlying these behavioral phenotypes fox-specific genomic resources are needed. Results cDNA from mRNA from pre-frontal cortex of a tame and an aggressive fox was sequenced using the Roche 454 FLX Titanium platform (> 2.5 million reads & 0.9 Gbase of tame fox sequence; >3.3 million reads & 1.2 Gbase of aggressive fox sequence). Over 80% of the fox reads were assembled into contigs. Mapping fox reads against the fox transcriptome assembly and the dog genome identified over 30,000 high confidence fox-specific SNPs. Fox transcripts for approximately 14,000 genes were identified using SwissProt and the dog RefSeq databases. An at least 2-fold expression difference between the two samples (p < 0.05) was observed for 335 genes, fewer than 3% of the total number of genes identified in the fox transcriptome. Conclusions Transcriptome sequencing significantly expanded genomic resources available for the fox, a species without a sequenced genome. In a very cost efficient manner this yielded a large number of fox-specific SNP markers for genetic studies and provided significant insights into the gene expression profile of the fox pre-frontal cortex; expression differences between the two fox samples; and a catalogue of potentially important gene-specific sequence variants. This result demonstrates the utility of this approach for developing genomic resources in species with limited genomic information. PMID:21967120

Sirt1 protects against oxidative stress-induced renal tubular cell apoptosis by the bidirectional regulation of catalase expression

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hasegawa, Kazuhiro; Wakino, Shu; Yoshioka, Kyoko

2008-07-18

NAD{sup +}-dependent protein deacetylase Sirt1 regulates cellular apoptosis. We examined the role of Sirt1 in renal tubular cell apoptosis by using HK-2 cells, proximal tubular cell lines with or without reactive oxygen species (ROS), H{sub 2}O{sub 2}. Without any ROS, Sirt1 inhibitors enhanced apoptosis and the expression of ROS scavenger, catalase, and Sirt1 overexpression downregulated catalase. When apoptosis was induced with H{sub 2}O{sub 2}, Sirt1 was upregulated with the concomitant increase in catalase expression. Sirt1 overexpression rescued H{sub 2}O{sub 2}-induced apoptosis through the upregulation of catalase. H{sub 2}O{sub 2} induced the nuclear accumulation of forkhead transcription factor, FoxO3a and themore » gene silencing of FoxO3a enhanced H{sub 2}O{sub 2}-induced apoptosis. In conclusion, endogenous Sirt1 maintains cell survival by regulating catalase expression and by preventing the depletion of ROS required for cell survival. In contrast, excess ROS upregulates Sirt1, which activates FoxO3a and catalase leading to rescuing apoptosis. Thus, Sirt1 constitutes a determinant of renal tubular cell apoptosis by regulating cellular ROS levels.« less

Endothelial FoxM1 Mediates Bone Marrow Progenitor Cell-Induced Vascular Repair and Resolution of Inflammation following Inflammatory Lung Injury

PubMed Central

Zhao, Yidan D.; Huang, Xiaojia; Yi, Fan; Dai, Zhiyu; Qian, Zhijian; Tiruppathi, Chinnaswamy; Tran, Khiem; Zhao, You-Yang

2015-01-01

Adult stem cell treatment is a potential novel therapeutic approach for acute respiratory distress syndrome. Given the extremely low rate of cell engraftment, it is believed that these cells exert their beneficial effects via paracrine mechanisms. However, the endogenous mediator(s) in the pulmonary vasculature remains unclear. Employing the mouse model with endothelial cell (EC)-restricted disruption of FoxM1 (FoxM1 CKO), here we show that endothelial expression of the reparative transcriptional factor FoxM1 is required for the protective effects of bone marrow progenitor cells (BMPC) against LPS-induced inflammatory lung injury and mortality. BMPC treatment resulted in rapid induction of FoxM1 expression in WT but not FoxM1 CKO lungs. BMPC-induced inhibition of lung vascular injury, resolution of lung inflammation, and survival, as seen in WT mice, were abrogated in FoxM1 CKO mice following LPS challenge. Mechanistically, BMPC treatment failed to induce lung EC proliferation in FoxM1 CKO mice, which was associated with impaired expression of FoxM1 target genes essential for cell cycle progression. We also observed that BMPC treatment enhanced endothelial barrier function in WT, but not in FoxM1-deficient EC monolayers. Restoration of β-catenin expression in FoxM1-deficient ECs normalized endothelial barrier enhancement in response to BMPC treatment. These data demonstrate the requisite role of endothelial FoxM1 in the mechanism of BMPC-induced vascular repair to restore vascular integrity and accelerate resolution of inflammation, thereby promoting survival following inflammatory lung injury. PMID:24578354

Comparative nutrient digestibility of arctic foxes (Alopex lagopus) on Svalbard and farm-raised blue foxes (Alopex lagopus).

PubMed

Ahlstrøm, Øystein; Fuglei, Eva; Mydland, Liv Torunn

2003-01-01

Arctic foxes from Svalbard (n=4) and farmed blue foxes (n=4) was used in a digestibility experiment with a high-carbohydrate feed to add more information to the nutritional physiology of the arctic fox, and to compare its digestive capacity with that of the farmed blue fox. The arctic fox has a diet containing mainly protein and fat from mammals and birds, while farmed blue foxes have been exposed to an omnivorous dietary regime for more than 80 generations. The experiment showed in general no difference in digestive capacity for protein and fat between the foxes (P>0.05), but for carbohydrates, including starch and glucose, the blue fox revealed higher digestibility values. The superior digestive capacity for carbohydrates in blue fox might be a result of a long-term selection of animals digesting dietary carbohydrates more efficiently, or that an early age exposition to dietary carbohydrates has given permanent improvement of the carbohydrate digestion in the gut.

Regulation of Akt/FoxO3a/Skp2 Axis Is Critically Involved in Berberine-Induced Cell Cycle Arrest in Hepatocellular Carcinoma Cells

PubMed Central

Li, Fanni; Dong, Xiwen; Lin, Peng; Jiang, Jianli

2018-01-01

The maintenance of ordinal cell cycle phases is a critical biological process in cancer genesis, which is a crucial target for anti-cancer drugs. As an important natural isoquinoline alkaloid from Chinese herbal medicine, Berberine (BBR) has been reported to possess anti-cancer potentiality to induce cell cycle arrest in hepatocellular carcinoma cells (HCC). However, the underlying mechanism remains to be elucidated. In our present study, G0/G1 phase cell cycle arrest was observed in berberine-treated Huh-7 and HepG2 cells. Mechanically, we observed that BBR could deactivate the Akt pathway, which consequently suppressed the S-phase kinase-associated protein 2 (Skp2) expression and enhanced the expression and translocation of Forkhead box O3a (FoxO3a) into nucleus. The translocated FoxO3a on one hand could directly promote the transcription of cyclin-dependent kinase inhibitors (CDKIs) p21Cip1 and p27Kip1, on the other hand, it could repress Skp2 expression, both of which lead to up-regulation of p21Cip1 and p27Kip1, causing G0/G1 phase cell cycle arrest in HCC. In conclusion, BBR promotes the expression of CDKIs p21Cip1 and p27Kip1 via regulating the Akt/FoxO3a/Skp2 axis and further induces HCC G0/G1 phase cell cycle arrest. This research uncovered a new mechanism of an anti-cancer effect of BBR. PMID:29360760

Profiling analysis of FOX gene family members identified FOXE1 as potential regulator of NSCLC development.

PubMed

Ji, G H; Cui, Y; Yu, H; Cui, X B

2016-09-30

Lung cancer is one of the most malignant tumors worldwide with a high mortality rate, which has not been improved since several decades ago. FOX gene family members have been reported to play extensive roles in regulating many biological processes and disorders. In order to clarify the contribution of FOX gene family members in lung cancer biology, we performed expression profiling analysis of FOX gene family members from FOXA to FOXR in lung cancer cell lines and tissue specimens by Real-time PCR, western blot and immunohistochemistry analysis. We found that FOXE1 was the only gene which was over-expressed in six out of eight lung cancer cell lines and human cancer tissue specimens (28 out of 35 cases with higher expression and 7 out of 35 cases with moderate expression). Further investigation showed that MMP2 gene was up-regulated, and autophagy markers such as LC3B, ATG5, ATG12 and BECLIN1, were down-regulated concomitant with the increase of FOXE1. These results implicated that FOXE1 may be an important regulator by targeting autophagy and MMPs pathways in lung cancer development.

A forkhead Transcription Factor Is Wound-Induced at the Planarian Midline and Required for Anterior Pole Regeneration

PubMed Central

Scimone, M. Lucila; Lapan, Sylvain W.; Reddien, Peter W.

2014-01-01

Planarian regeneration requires positional information to specify the identity of tissues to be replaced as well as pluripotent neoblasts capable of differentiating into new cell types. We found that wounding elicits rapid expression of a gene encoding a Forkhead-family transcription factor, FoxD. Wound-induced FoxD expression is specific to the ventral midline, is regulated by Hedgehog signaling, and is neoblast-independent. FoxD is subsequently expressed within a medial subpopulation of neoblasts at wounds involving head regeneration. Ultimately, FoxD is co-expressed with multiple anterior markers at the anterior pole. Inhibition of FoxD with RNA interference (RNAi) results in the failure to specify neoblasts expressing anterior markers (notum and prep) and in anterior pole formation defects. FoxD(RNAi) animals fail to regenerate a new midline and to properly pattern the anterior blastema, consistent with a role for the anterior pole in organizing pattern of the regenerating head. Our results suggest that wound signaling activates a forkhead transcription factor at the midline and, if the head is absent, FoxD promotes specification of neoblasts at the prior midline for anterior pole regeneration. PMID:24415944

Loss of TIMP3 underlies diabetic nephropathy via FoxO1/STAT1 interplay.

PubMed

Fiorentino, Loredana; Cavalera, Michele; Menini, Stefano; Marchetti, Valentina; Mavilio, Maria; Fabrizi, Marta; Conserva, Francesca; Casagrande, Viviana; Menghini, Rossella; Pontrelli, Paola; Arisi, Ivan; D'Onofrio, Mara; Lauro, Davide; Khokha, Rama; Accili, Domenico; Pugliese, Giuseppe; Gesualdo, Loreto; Lauro, Renato; Federici, Massimo

2013-03-01

ADAM17 and its inhibitor TIMP3 are involved in nephropathy, but their role in diabetic kidney disease (DKD) is unclear. Diabetic Timp3(-/-) mice showed increased albuminuria, increased membrane thickness and mesangial expansion. Microarray profiling uncovered a significant reduction of Foxo1 expression in diabetic Timp3(-/-) mice compared to WT, along with FoxO1 target genes involved in autophagy, while STAT1, a repressor of FoxO1 transcription, was increased. Re-expression of Timp3 in Timp3(-/-) mesangial cells rescued the expression of Foxo1 and its targets, and decreased STAT1 expression to control levels; abolishing STAT1 expression led to a rescue of FoxO1, evoking a role of STAT1 in linking Timp3 deficiency to FoxO1. Studies on kidney biopsies from patients with diabetic nephropathy confirmed a significant reduction in TIMP3, FoxO1 and FoxO1 target genes involved in autophagy compared to controls, while STAT1 expression was strongly increased. Our study suggests that loss of TIMP3 is a hallmark of DKD in human and mouse models and designates TIMP3 as a new possible therapeutic target for diabetic nephropathy. Copyright © 2013 The Authors. Published by John Wiley and Sons, Ltd on behalf of EMBO.

Temporal regulation of epithelium formation mediated by FoxA, MKLP1, MgcRacGAP, and PAR-6

PubMed Central

Von Stetina, Stephen E.; Liang, Jennifer; Marnellos, Georgios; Mango, Susan E.

2017-01-01

To establish the animal body plan, embryos link the external epidermis to the internal digestive tract. In Caenorhabditis elegans, this linkage is achieved by the arcade cells, which form an epithelial bridge between the foregut and epidermis, but little is known about how development of these three epithelia is coordinated temporally. The arcade cell epithelium is generated after the epidermis and digestive tract epithelia have matured, ensuring that both organs can withstand the mechanical stress of embryo elongation; mistiming of epithelium formation leads to defects in morphogenesis. Using a combination of genetic, bioinformatic, and imaging approaches, we find that temporal regulation of the arcade cell epithelium is mediated by the pioneer transcription factor and master regulator PHA-4/FoxA, followed by the cytoskeletal regulator and kinesin ZEN-4/MKLP1 and the polarity protein PAR-6. We show that PHA-4 directly activates mRNA expression of a broad cohort of epithelial genes, including junctional factor dlg-1. Accumulation of DLG-1 protein is delayed by ZEN-4, acting in concert with its binding partner CYK-4/MgcRacGAP. Our structure–function analysis suggests that nuclear and kinesin functions are dispensable, whereas binding to CYK-4 is essential, for ZEN-4 function in polarity. Finally, PAR-6 is necessary to localize polarity proteins such as DLG-1 within adherens junctions and at the apical surface, thereby generating arcade cell polarity. Our results reveal that the timing of a landmark event during embryonic morphogenesis is mediated by the concerted action of four proteins that delay the formation of an epithelial bridge until the appropriate time. In addition, we find that mammalian FoxA associates with many epithelial genes, suggesting that direct regulation of epithelial identity may be a conserved feature of FoxA factors and a contributor to FoxA function in development and cancer. PMID:28539408

Altered balance between self-reactive T helper (Th)17 cells and Th10 cells and between full-length forkhead box protein 3 (FoxP3) and FoxP3 splice variants in Hashimoto's thyroiditis.

PubMed

Kristensen, B; Hegedüs, L; Madsen, H O; Smith, T J; Nielsen, C H

2015-04-01

T helper type 17 (Th17) cells play a pathogenic role in autoimmune disease, while interleukin (IL)-10-producing Th10 cells serve a protective role. The balance between the two subsets is regulated by the local cytokine milieu and by the relative expression of intact forkhead box protein 3 (FoxP3) compared to FoxP3Δ2, missing exon 2. Th17 and Th10 cell differentiation has usually been studied using polyclonal stimuli, and little is known about the ability of physiologically relevant self-antigens to induce Th17 or Th10 cell differentiation in autoimmune thyroid disease. We subjected mononuclear cells from healthy donors and patients with Hashimoto's thyroiditis (HT) or Graves' disease (GD) to polyclonal stimulation, or stimulation with human thyroglobulin (TG), human thyroid peroxidase (TPO), or Esherichia coli lipopolysaccharide (LPS). TPO and LPS induced increased differentiation of naive CD4(+) CD45RA(+) CD45R0(-) T cells from HT patients into Th17 cells. Th10 cell proportions were decreased in HT after polyclonal stimulation, but were comparable to those of healthy donors after antigen-specific stimulation. Taken together, our data show that an increased Th17 : Th10 ratio was found in HT patients after stimulation with thyroid-specific self-antigens. We also observed an elevated baseline production of IL-6 and transforming growth factor (TGF)-β1 and of mRNA encoding FoxP3Δ2 rather than intact FoxP3. This may contribute to the skewing towards Th17 cell responses in HT. © 2014 British Society for Immunology.

Dual effects of fructose on ChREBP and FoxO1/3α are responsible for AldoB up-regulation and vascular remodelling.

PubMed

Cao, Wei; Chang, Tuanjie; Li, Xiao-Qiang; Wang, Rui; Wu, Lingyun

2017-02-01

Increased production of methylglyoxal (MG) in vascular tissues is one of the causative factors for vascular remodelling in different subtypes of metabolic syndrome, including hypertension and insulin resistance. Fructose-induced up-regulation of aldolase B (AldoB) contributes to increased vascular MG production but the underlying mechanisms are unclear. Serum levels of MG and fructose were determined in diabetic patients with hypertension. MG level had significant positive correlations with blood pressure and fructose level respectively. C57BL/6 mice were fed with control or fructose-enriched diet for 3 months and ultrasonographic and histologic analyses were performed to evaluate arterial structural changes. Fructose-fed mice exhibited hypertension and high levels of serum MG with normal glucose level. Fructose intake increased blood vessel wall thickness and vascular smooth muscle cell (VSMC) proliferation. Western blotting and real-time PCR analysis revealed that AldoB level was significantly increased in both the aorta of fructose-fed mice and the fructose-treated VSMCs, whereas aldolase A (AldoA) expression was not changed. The knockdown of AldoB expression prevented fructose-induced MG overproduction and VSMC proliferation. Moreover, fructose significantly increased carbohydrate-responsive element-binding protein (ChREBP), phosphorylated FoxO1/3α and Akt1 levels. Fructose induced translocation of ChREBP from the cytosol to nucleus and activated AldoB gene expression, which was inhibited by the knockdown of ChREBP. Meanwhile, fructose caused FoxO1/3α shuttling from the nucleus to cytosol and inhibited its binding to AldoB promoter region. Fructose-induced AldoB up-regulation was suppressed by Akt1 inhibitor but enhanced by FoxO1/3α siRNA. Collectively, fructose activates ChREBP and inactivates FoxO1/3α pathways to up-regulate AldoB expression and MG production, leading to vascular remodelling. © 2017 The Author(s). published by Portland Press Limited on behalf of the Biochemical Society.

Over-expression of FoxM1 leads to epithelial-mesenchymal transition and cancer stem cell phenotype in pancreatic cancer cells

PubMed Central

Bao, Bin; Wang, Zhiwei; Ali, Shadan; Kong, Dejuan; Banerjee, Sanjeev; Ahmad, Aamir; Li, Yiwei; Azmi, Asfar S.; Miele, Lucio; Sarkar, Fazlul H.

2011-01-01

FoxM1 is known to play important role in the development and progression of many malignancies including pancreatic cancer. Studies have shown that the acquisition of Epithelial-to-mesenchymal transition (EMT) phenotype and induction of cancer stem cell (CSC) or cancer stem-like cell phenotypes are highly inter-related, and contributes to drug resistance, tumor recurrence and metastasis. The molecular mechanism(s) by which FoxM1 contributes to the acquisition of EMT phenotype and induction of CSC self-renewal capacity is poorly understood. Therefore, we established FoxM1 over-expressing pancreatic cancer (AsPC-1) cells, which showed increased cell growth, clonogenicity and cell migration. Moreover, over-expression of FoxM1 led to the acquisition of EMT phenotype by activation of mesenchymal cell markers, ZEB1, ZEB2, Snail2, E-cadherin, and vimentin, which is consistent with increased sphere-forming (pancreatospheres) capacity and expression of CSC surface markers (CD44 and EpCAM). We also found that over-expression of FoxM1 led to decreased expression of miRNAs (let-7a, let-7b, let-7c, miR-200b and miR-200c); however, re-expression of miR-200b inhibited the expression of ZEB1, ZEB2, vimentin as well as FoxM1, and induced the expression of E-cadherin, leading to the reversal of EMT phenotype. Finally, we found that genistein, a natural chemo-preventive agent, inhibited cell growth, clonogenicity, cell migration and invasion, EMT phenotype, and formation of pancreatospheres consistent with reduced expression of CD44 and EpCAM. These results suggest, for the first time, that FoxM1 over-expression is responsible for the acquisition of EMT and CSC phenotype, which is in part mediated through the regulation of miR-200b and these processes, could be easily attenuated by genistein. PMID:21503965

Increased Expression of FoxM1 Transcription Factor in Respiratory Epithelium Inhibits Lung Sacculation and Causes Clara Cell Hyperplasia

PubMed Central

Wang, I-Ching; Zhang, Yufang; Snyder, Jonathan; Sutherland, Mardi J.; Burhans, Michael S.; Shannon, John M.; Park, Hyun Jung; Whitsett, Jeffrey A.; Kalinichenko, Vladimir V.

2010-01-01

Foxm1 is a member of the Forkhead Box (Fox) family of transcription factors. Foxm1 (previously called Foxm1b, HFH-11B, Trident, Win, or MPP2) is expressed in multiple cell types and plays important roles in cellular proliferation, differentiation and tumorigenesis. Genetic deletion of Foxm1 from mouse respiratory epithelium during initial stages of lung development inhibits lung maturation and causes respiratory failure after birth. However, the role of Foxm1 during postnatal lung morphogenesis remains unknown. In the present study, Foxm1 expression was detected in epithelial cells of conducting and peripheral airways and changing dynamically with lung maturation. To discern the biological role of Foxm1 in the prenatal and postnatal lung, a novel transgenic mouse line that expresses a constitutively active form of FoxM1 (FoxM1 N-terminal deletion mutant or FoxM1-ΔN) under the control of lung epithelial-specific SPC promoter was produced. Expression of the FoxM1-ΔN transgene during embryogenesis caused epithelial hyperplasia, inhibited lung sacculation and expression of the type II epithelial marker, pro-SPC. Expression of FoxM1-ΔN mutant during the postnatal period did not influence alveologenesis but caused focal airway hyperplasia and increased proliferation of Clara cells. Likewise, expression of FoxM1-ΔN mutant in conducting airways with Scgb1a1 promoter was sufficient to induce Clara cell hyperplasia. Furthermore, FoxM1-ΔN cooperated with activated K-Ras to induce lung tumor growth in vivo. Increased activity of Foxm1 altered lung sacculation, induced proliferation in the respiratory epithelium and accelerated lung tumor growth, indicating that precise regulation of Foxm1 is critical for normal lung morphogenesis and development of lung cancer. PMID:20816795

SCP4 Promotes gluconeogenesis through Fox01/3a dephosphorylation

USDA-ARS?s Scientific Manuscript database

FoxO1 and FoxO3a (collectively FoxO1/3a) proteins regulate a wide array of cellular processes, including hepatic gluconeogenesis. Phosphorylation of FoxO1/3a is a key event that determines its subcellular location and transcriptional activity. During glucose synthesis, the activity of FoxO1/3a is ne...

FoxP2 directly regulates the reelin receptor VLDLR developmentally and by singing.

PubMed

Adam, Iris; Mendoza, Ezequiel; Kobalz, Ursula; Wohlgemuth, Sandra; Scharff, Constance

2016-07-01

Mutations of the transcription factor FOXP2 cause a severe speech and language disorder. In songbirds, FoxP2 is expressed in the medium spiny neurons (MSNs) of the avian basal ganglia song nucleus, Area X, which is crucial for song learning and adult song performance. Experimental downregulation of FoxP2 in Area X affects spine formation, prevents neuronal plasticity induced by social context and impairs song learning. Direct target genes of FoxP2 relevant for song learning and song production are unknown. Here we show that a lentivirally mediated FoxP2 knockdown in Area X of zebra finches downregulates the expression of VLDLR, one of the two reelin receptors. Zebra finch FoxP2 binds to the promoter of VLDLR and activates it, establishing VLDLR as a direct FoxP2 target. Consistent with these findings, VLDLR expression is co-regulated with FoxP2 as a consequence of adult singing and during song learning. We also demonstrate that knockdown of FoxP2 affects glutamatergic transmission at the corticostriatal MSN synapse. These data raise the possibility that the regulatory relationship between FoxP2 and VLDLR guides structural plasticity towards the subset of FoxP2-positive MSNs in an activity dependent manner via the reelin pathway. Copyright © 2016 Elsevier Inc. All rights reserved.

Isotretinoin and FoxO1

PubMed Central

2011-01-01

Oral isotretinoin (13-cis retinoic acid) is the most effective drug in the treatment of acne and restores all major pathogenetic factors of acne vulgaris. isotretinoin is regarded as a prodrug which after isomerizisation to all-trans-retinoic acid (ATRA) induces apoptosis in cells cultured from human sebaceous glands, meibomian glands, neuroblastoma cells, hypothalamic cells, hippocampus cells, Dalton's lymphoma ascites cells, B16F-10 melanoma cells, and neuronal crest cells and others. By means of translational research this paper provides substantial indirect evidence for isotretinoin's mode of action by upregulation of forkhead box class O (FoxO) transcription factors. FoxOs play a pivotal role in the regulation of androgen receptor transactivation, insulin/insulin like growth factor-1 (IGF-1)-signaling, peroxisome proliferator-activated receptor-γ (PPArγ)- and liver X receptor-α (LXrα)-mediated lipogenesis, β-catenin signaling, cell proliferation, apoptosis, reactive oxygene homeostasis, innate and acquired immunity, stem cell homeostasis, as well as anti-cancer effects. An accumulating body of evidence suggests that the therapeutic, adverse, teratogenic and chemopreventive effecs of isotretinoin are all mediated by upregulation of FoxO-mediated gene transcription. These FoxO-driven transcriptional changes of the second response of retinoic acid receptor (RAR)-mediated signaling counterbalance gene expression of acne due to increased growth factor signaling with downregulated nuclear FoxO proteins. The proposed isotretinoin→ATRA→RAR→FoxO interaction offers intriguing new insights into the mode of isotretinoin action and explains most therapeutic, adverse and teratogenic effects of isotretinoin in the treatment of acne by a common mode of FoxO-mediated transcriptional regulation. PMID:22110774

Targeting forkhead box transcription factors FOXM1 and FOXO in leukemia (Review).

PubMed

Zhu, Hong

2014-10-01

Deregulation of forkhead box (FOX) proteins has been found in many genetic diseases and malignancies including leukemia. Leukemia is a common neoplastic disease of the blood or bone marrow characterized by the presence of immature leukocytes and is one of the leading causes of death due to cancer. Forkhead transcription factors, FOXM1 and FOXO family members (FOXOs), are important mediators in leukemia development. Aberrant expression of FOXM1 and FOXOs results in leukemogenesis. Usually the expression of FOXM1 is upregulated, whereas the expression of FOXOs is downregulated due to phosphorylation, nuclear exclusion and degradation in leukemia. On the one hand, FOXOs are bona fide tumor suppressors, on the other hand, active FOXOs maintain leukemia stem cells and stimulate drug resistance genes, contributing to leukemogenesis. FOXM1 and FOXOs have been proven to be potential targets for the development of leukemia therapeutics. They are also valuable diagnostic and prognostic markers in leukemia for clinical applications. This review summarizes the present knowledge concerning the molecular mechanisms by which FOXM1 and FOXOs modulate leukemogenesis and leukemia development, the clinical relevance of these FOX proteins in leukemia and related areas that warrant further investigation.

Essential roles of FoxM1 in Ras-induced liver cancer progression and in cancer cells with stem cell features.

PubMed

Kopanja, Dragana; Pandey, Akshay; Kiefer, Megan; Wang, Zebin; Chandan, Neha; Carr, Janai R; Franks, Roberta; Yu, Dae-Yeul; Guzman, Grace; Maker, Ajay; Raychaudhuri, Pradip

2015-08-01

Overexpression of FoxM1 correlates with poor prognosis in hepatocellular carcinoma (HCC). Moreover, the Ras-signaling pathway is found to be ubiquitously activated in HCC through epigenetic silencing of the Ras-regulators. We investigated the roles of FoxM1 in Ras-driven HCC, and on HCC cells with stem-like features. We employed a transgenic mouse model that expresses the oncogenic Ras in the liver. That strain was crossed with a strain that harbor floxed alleles of FoxM1 and the MxCre gene that allows conditional deletion of FoxM1. FoxM1 alleles were deleted after development of HCC, and the effects on the tumors were analyzed. Also, FoxM1 siRNA was used in human HCC cell lines to determine its role in the survival of the HCC cells with stem cell features. Ras-driven tumors overexpress FoxM1. Deletion of FoxM1 inhibits HCC progression. There was increased accumulation of reactive oxygen species (ROS) in the FoxM1 deleted HCC cells. Moreover, FoxM1 deletion caused a disproportionate loss of the CD44+ and EpCAM+ HCC cells in the tumors. We show that FoxM1 directly activates expression of CD44 in human HCC cells. Moreover, the human HCC cells with stem cell features are addicted to FoxM1 for ROS-regulation and survival. Our results provide genetic evidence for an essential role of FoxM1 in the progression of Ras-driven HCC. In addition, FoxM1 is required for the expression of CD44 in HCC cells. Moreover, FoxM1 plays a critical role in the survival of the HCC cells with stem cell features by regulating ROS. Published by Elsevier B.V.

FoxM1 Promotes Stemness and Radio-Resistance of Glioblastoma by Regulating the Master Stem Cell Regulator Sox2

PubMed Central

Kim, Dong Geon; Cho, Hee Jin; Kim, Yeonghwan; Rheey, Jinguen; Shin, Kayoung; Seo, Yun Jee; Choi, Yeon-Sook; Lee, Jung-Il; Lee, Jeongwu; Joo, Kyeung Min; Nam, Do-Hyun

2015-01-01

Glioblastoma (GBM) is the most aggressive and most lethal brain tumor. As current standard therapy consisting of surgery and chemo-irradiation provides limited benefit for GBM patients, novel therapeutic options are urgently required. Forkhead box M1 (FoxM1) transcription factor is an oncogenic regulator that promotes the proliferation, survival, and treatment resistance of various human cancers. The roles of FoxM1 in GBM remain incompletely understood, due in part to pleotropic nature of the FoxM1 pathway. Here, we show the roles of FoxM1 in GBM stem cell maintenance and radioresistance. ShRNA-mediated FoxM1 inhibition significantly impeded clonogenic growth and survival of patient-derived primary GBM cells with marked downregulation of Sox2, a master regulator of stem cell phenotype. Ectopic expression of Sox2 partially rescued FoxM1 inhibition-mediated effects. Conversely, FoxM1 overexpression upregulated Sox2 expression and promoted clonogenic growth of GBM cells. These data, with a direct binding of FoxM1 in the Sox2 promoter region in GBM cells, suggest that FoxM1 regulates stemness of primary GBM cells via Sox2. We also found significant increases in FoxM1 and Sox2 expression in GBM cells after irradiation both in vitro and in vivo orthotopic tumor models. Notably, genetic or a small-molecule FoxM1 inhibitor-mediated FoxM1 targeting significantly sensitized GBM cells to irradiation, accompanying with Sox2 downregulation. Finally, FoxM1 inhibition combined with irradiation in a patient GBM-derived orthotopic model significantly impeded tumor growth and prolonged the survival of tumor bearing mice. Taken together, these results indicate that the FoxM1-Sox2 signaling axis promotes clonogenic growth and radiation resistance of GBM, and suggest that FoxM1 targeting combined with irradiation is a potentially effective therapeutic approach for GBM. PMID:26444992

FoxM1 Promotes Stemness and Radio-Resistance of Glioblastoma by Regulating the Master Stem Cell Regulator Sox2.

PubMed

Lee, Yeri; Kim, Kang Ho; Kim, Dong Geon; Cho, Hee Jin; Kim, Yeonghwan; Rheey, Jinguen; Shin, Kayoung; Seo, Yun Jee; Choi, Yeon-Sook; Lee, Jung-Il; Lee, Jeongwu; Joo, Kyeung Min; Nam, Do-Hyun

2015-01-01

Glioblastoma (GBM) is the most aggressive and most lethal brain tumor. As current standard therapy consisting of surgery and chemo-irradiation provides limited benefit for GBM patients, novel therapeutic options are urgently required. Forkhead box M1 (FoxM1) transcription factor is an oncogenic regulator that promotes the proliferation, survival, and treatment resistance of various human cancers. The roles of FoxM1 in GBM remain incompletely understood, due in part to pleotropic nature of the FoxM1 pathway. Here, we show the roles of FoxM1 in GBM stem cell maintenance and radioresistance. ShRNA-mediated FoxM1 inhibition significantly impeded clonogenic growth and survival of patient-derived primary GBM cells with marked downregulation of Sox2, a master regulator of stem cell phenotype. Ectopic expression of Sox2 partially rescued FoxM1 inhibition-mediated effects. Conversely, FoxM1 overexpression upregulated Sox2 expression and promoted clonogenic growth of GBM cells. These data, with a direct binding of FoxM1 in the Sox2 promoter region in GBM cells, suggest that FoxM1 regulates stemness of primary GBM cells via Sox2. We also found significant increases in FoxM1 and Sox2 expression in GBM cells after irradiation both in vitro and in vivo orthotopic tumor models. Notably, genetic or a small-molecule FoxM1 inhibitor-mediated FoxM1 targeting significantly sensitized GBM cells to irradiation, accompanying with Sox2 downregulation. Finally, FoxM1 inhibition combined with irradiation in a patient GBM-derived orthotopic model significantly impeded tumor growth and prolonged the survival of tumor bearing mice. Taken together, these results indicate that the FoxM1-Sox2 signaling axis promotes clonogenic growth and radiation resistance of GBM, and suggest that FoxM1 targeting combined with irradiation is a potentially effective therapeutic approach for GBM.

Organization of the gymnotiform fish pallium in relation to learning and memory: IV. Expression of conserved transcription factors and implications for the evolution of dorsal telencephalon.

PubMed

Harvey-Girard, Erik; Giassi, Ana C C; Ellis, William; Maler, Leonard

2012-10-15

We have cloned the apteronotid homologs of FoxP2, Otx1, and FoxO3. There was, in the case of all three genes, good similarity between the apteronotid and human amino acid sequences: FoxP2, 78%; Otx1, 54%; FoxO3, 71%. The functional domains of these genes were conserved to a far greater extent, on average: FoxP2, 89%; Otx1, 76%; FoxO3, 82%. This led us to hypothesize that the cellular functions of these genes might also be conserved. We used in situ hybridization to examine the distribution of the mRNA transcripts of these genes in the apteronotid telencephalon. We confined our analysis to the pallial regions previously associated with learning about social signals, whose circuitry has been closely examined in the other articles of this series. We found that AptFoxP2 and AptOtx1 transcripts were expressed predominantly in the dorsocentral division of the pallium (DC); the dorsolateral division of the pallium (DL) contained only weakly labeled neurons. In both cases, the distribution of labeled neurons was very heterogeneous, and unlabeled neurons could be found adjacent to strongly labeled ones. In contrast, we found that most neurons in DL strongly expressed AptFoxO3 mRNA, although there was only weak expression in a small number of cells within DC. We briefly discuss the relevance of our results regarding the functional roles of AptFoxP2/AptOtx1-expressing neurons in DC for communication vs. foraging behavior. We extensively discuss the implications of our results for possible homologies between DL and DC and medial and dorsal pallium of tetrapods, respectively. Copyright © 2012 Wiley Periodicals, Inc.

The transcriptional repressor DREAM is involved in thyroid gene expression

DOE Office of Scientific and Technical Information (OSTI.GOV)

D'Andrea, Barbara; Di Palma, Tina; Mascia, Anna

2005-04-15

Downstream regulatory element antagonistic modulator (DREAM) was originally identified in neuroendocrine cells as a calcium-binding protein that specifically binds to downstream regulatory elements (DRE) on DNA, and represses transcription of its target genes. To explore the possibility that DREAM may regulate the endocrine activity of the thyroid gland, we analyzed its mRNA expression in undifferentiated and differentiated thyroid cells. We demonstrated that DREAM is expressed in the normal thyroid tissue as well as in differentiated thyroid cells in culture while it is absent in FRT poorly differentiated cells. In the present work, we also show that DREAM specifically binds tomore » DRE sites identified in the 5' untranslated region (UTR) of the thyroid-specific transcription factors Pax8 and TTF-2/FoxE1 in a calcium-dependent manner. By gel retardation assays we demonstrated that thapsigargin treatment increases the binding of DREAM to the DRE sequences present in Pax8 and TTF-2/Foxe1 5' UTRs, and this correlates with a significant reduction of the expression of these genes. Interestingly, in poorly differentiated thyroid cells overexpression of exogenous DREAM strongly inhibits Pax8 expression. Moreover, we provide evidence that a mutated form of DREAM unable to bind Ca{sup 2+} interferes with thyroid cell proliferation. Therefore, we propose that in thyroid cells DREAM is a mediator of the calcium-signaling pathway and it is involved in the regulation of thyroid cell function.« less

FoxP2 Expression in a Highly Vocal Teleost Fish with Comparisons to Tetrapods.

PubMed

Pengra, Ian G G; Marchaterre, Margaret A; Bass, Andrew H

2018-04-19

Motivated by studies of speech deficits in humans, several studies over the past two decades have investigated the potential role of a forkhead domain transcription factor, FoxP2, in the central control of acoustic signaling/vocalization among vertebrates. Comparative neuroanatomical studies that mainly include mammalian and avian species have mapped the distribution of FoxP2 expression in multiple brain regions that imply a greater functional significance beyond vocalization that might be shared broadly across vertebrate lineages. To date, reports for teleost fish have been limited in number and scope to nonvocal species. Here, we map the neuroanatomical distribution of FoxP2 mRNA expression in a highly vocal teleost, the plainfin midshipman (Porichthys notatus). We report an extensive overlap between FoxP2 expression and vocal, auditory, and steroid-signaling systems with robust expression at multiple sites in the telencephalon, the preoptic area, the diencephalon, and the midbrain. Label was far more restricted in the hindbrain though robust in one region of the reticular formation. A comparison with other teleosts and tetrapods suggests an evolutionarily conserved FoxP2 phenotype important to vocal-acoustic and, more broadly, sensorimotor function among vertebrates. © 2018 S. Karger AG, Basel.

Targeting the UPR transcription factor XBP1 protects against Huntington's disease through the regulation of FoxO1 and autophagy

PubMed Central

Vidal, Rene L.; Figueroa, Alicia; Court, Felipe A.; Thielen, Peter; Molina, Claudia; Wirth, Craig; Caballero, Benjamin; Kiffin, Roberta; Segura-Aguilar, Juan; Cuervo, Ana Maria; Glimcher, Laurie H.; Hetz, Claudio

2012-01-01

Mutations leading to expansion of a poly-glutamine track in Huntingtin (Htt) cause Huntington's disease (HD). Signs of endoplasmic reticulum (ER) stress have been recently reported in animal models of HD, associated with the activation of the unfolded protein response (UPR). Here we have investigated the functional contribution of ER stress to HD by targeting the expression of two main UPR transcription factors, XBP1 and ATF4 (activating transcription factor 4), in full-length mutant Huntingtin (mHtt) transgenic mice. XBP1-deficient mice were more resistant to developing disease features, associated with improved neuronal survival and motor performance, and a drastic decrease in mHtt levels. The protective effects of XBP1 deficiency were associated with enhanced macroautophagy in both cellular and animal models of HD. In contrast, ATF4 deficiency did not alter mHtt levels. Although, XBP1 mRNA splicing was observed in the striatum of HD transgenic brains, no changes in the levels of classical ER stress markers were detected in symptomatic animals. At the mechanistic level, we observed that XBP1 deficiency led to augmented expression of Forkhead box O1 (FoxO1), a key transcription factor regulating autophagy in neurons. In agreement with this finding, ectopic expression of FoxO1 enhanced autophagy and mHtt clearance in vitro. Our results provide strong evidence supporting an involvement of XBP1 in HD pathogenesis probably due to an ER stress-independent mechanism involving the control of FoxO1 and autophagy levels. PMID:22337954

Two cysteine substitutions in the MC1R generate the blue variant of the Arctic fox (Alopex lagopus) and prevent expression of the white winter coat.

PubMed

Våge, Dag Inge; Fuglei, Eva; Snipstad, Kristin; Beheim, Janne; Landsem, Veslemøy Malm; Klungland, Helge

2005-10-01

We have characterized two mutations in the MC1R gene of the blue variant of the arctic fox (Alopex lagopus) that both incorporate a novel cysteine residue into the receptor. A family study in farmed arctic foxes verified that the dominant expression of the blue color phenotype cosegregates completely with the allele harboring these two mutations. Additionally to the altered pigment synthesis, the blue fox allele suppresses the seasonal change in coat color found in the native arctic fox. Consequently, these findings suggest that the MC1R/agouti regulatory system is involved in the seasonal changes of coat color found in arctic fox.

Ursolic acid improves domoic acid-induced cognitive deficits in mice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, Dong-mei; Key Laboratory for Biotechnology on Medicinal Plants of Jiangsu Province, School of Life Science, Xuzhou Normal University, Xuzhou 221116, Jiangsu Province; Lu, Jun, E-mail: lu-jun75@163.com

Our previous findings suggest that mitochondrial dysfunction is the mechanism underlying cognitive deficits induced by domoic acid (DA). Ursolic acid (UA), a natural triterpenoid compound, possesses many important biological functions. Evidence shows that UA can activate PI3K/Akt signaling and suppress Forkhead box protein O1 (FoxO1) activity. FoxO1 is an important regulator of mitochondrial function. Here we investigate whether FoxO1 is involved in the oxidative stress-induced mitochondrial dysfunction in DA-treated mice and whether UA inhibits DA-induced mitochondrial dysfunction and cognitive deficits through regulating the PI3K/Akt and FoxO1 signaling pathways. Our results showed that FoxO1 knockdown reversed the mitochondrial abnormalities and cognitivemore » deficits induced by DA in mice through decreasing HO-1 expression. Mechanistically, FoxO1 activation was associated with oxidative stress-induced JNK activation and decrease of Akt phosphorylation. Moreover, UA attenuated the mitochondrial dysfunction and cognitive deficits through promoting Akt phosphorylation and FoxO1 nuclear exclusion in the hippocampus of DA-treated mice. LY294002, an inhibitor of PI3K/Akt signaling, significantly decreased Akt phosphorylation in the hippocampus of DA/UA mice, which weakened UA actions. These results suggest that UA could be recommended as a possible candidate for the prevention and therapy of cognitive deficits in excitotoxic brain disorders. - Highlights: • Ursolic acid (UA) is a naturally triterpenoid compound. • UA attenuated the mitochondrial dysfunction and cognitive deficits. • Mechanistically, UA activates PI3K/Akt signaling and suppresses FoxO1 activity. • UA could be recommended as a possible candidate for anti-excitotoxic brain disorders.« less

Forkhead Box M1 Is Regulated by Heat Shock Factor 1 and Promotes Glioma Cells Survival under Heat Shock Stress*

PubMed Central

Dai, Bingbing; Gong, Aihua; Jing, Zhitao; Aldape, Kenneth D.; Kang, Shin-Hyuk; Sawaya, Raymond; Huang, Suyun

2013-01-01

The forkhead box M1 (FoxM1) is a key transcription factor regulating multiple aspects of cell biology. Prior studies have shown that FoxM1 is overexpressed in a variety of human tumors, including brain tumor, and plays a critical role in cancer development and progression. In this study we found that FoxM1 was up-regulated by heat shock factor 1 (HSF1) under heat shock stress condition in multiple cell lines. Knockdown of HSF1 with HSF1 siRNA or inhibition of HSF1 with a HSF1 inhibitor abrogated heat shock-induced expression of FoxM1. Genetic deletion of HSF1 in mouse embryo fibroblast cells also abolished heat shock stress-induced FoxM1 expression. Moreover, we showed that HSF1 directly bound to FoxM1 promoter and increased FoxM1 promoter activity. Furthermore, we demonstrated that FoxM1 was required for the G2-M phase progression through regulating Cdc2, Cdc20, and Cdc25B under a mild heat shock stress but enhanced cell survival under lethal heat shock stress condition. Finally, in human glioblastoma specimens, FoxM1 overexpression correlated with elevated HSF1 expression. Our results indicate that FoxM1 is regulated by HSF1 and is critical for HSF1-mediated heat shock response. We demonstrated a novel mechanism of stress resistance controlled by HSF1 and a new HSF-FoxM1 connection that mediates cellular thermotolerance. PMID:23192351

Neurotoxic flying foxes as dietary items for the Chamorro people, Marianas Islands.

PubMed

Banack, Sandra Anne; Murch, Susan J; Cox, Paul Alan

2006-06-15

Fanihi -- flying foxes (Pteropus mariannus mariannus, Pteropodidae) -- are a highly salient component of the traditional Chamorro diet. A neurotoxic, non-protein amino acid, beta-methylamino-l-alanine (BMAA) accumulates in flying foxes, which forage on the seeds of Cycas micronesica (Cycadaceae) in Guam's forests. BMAA occurs throughout flying fox tissues both as a free amino acid and in a protein-bound form. It is not destroyed by cooking. Protein-bound BMAA also remains in cycad flour which has been washed and prepared by the Chamorro people as tortillas, dumplings, and thickened soups. Other animals that forage on cycad seeds may also provide BMAA inputs into the traditional Chamorro diet.

A base substitution in the donor site of intron 12 of KIT gene is responsible for the dominant white coat colour of blue fox (Alopex lagopus).

PubMed

Yan, S Q; Hou, J N; Bai, C Y; Jiang, Y; Zhang, X J; Ren, H L; Sun, B X; Zhao, Z H; Sun, J H

2014-04-01

The dominant white coat colour of farmed blue fox is inherited as a monogenic autosomal dominant trait and is suggested to be embryonic lethal in the homozygous state. In this study, the transcripts of KIT were identified by RT-PCR for a dominant white fox and a normal blue fox. Sequence analysis showed that the KIT transcript in normal blue fox contained the full-length coding sequence of 2919 bp (GenBank Acc. No KF530833), but in the dominant white individual, a truncated isoform lacking the entire exon 12 specifically co-expressed with the normal transcript. Genomic DNA sequencing revealed that a single nucleotide polymorphism (c.1867+1G>T) in intron 12 appeared only in the dominant white individuals and a 1-bp ins/del polymorphism in the same intron showed in individuals representing two different coat colours. Genotyping results of the SNP with PCR-RFLP in 185 individuals showed all 90 normal blue foxes were homozygous for the G allele, and all dominant white individuals were heterozygous. Due to the truncated protein with a deletion of 35 amino acids and an amino acid replacement (p.Pro623Ala) located in the conserved ATP binding domain, we propose that the mutant receptor had absent tyrosine kinase activity. These findings reveal that the base substitution at the first nucleotide of intron 12 of KIT gene, resulting in skipping of exon 12, is a causative mutation responsible for the dominant white phenotype of blue fox. © 2013 Stichting International Foundation for Animal Genetics.

Cloning of fox (Vulpes vulpes) Il2, Il6, Il10 and IFNgamma and analysis of their expression by quantitative RT-PCR in fox PBMC after in vitro stimulation by Concanavalin A.

PubMed

Rolland-Turner, Magali; Farré, Guillaume; Boué, Franck

2006-04-15

The immune response in the fox (Vulpes vulpes), despite the success of the oral rabies vaccine is not well characterised, and specific immunological tools are needed. A quantitative RT-PCR using SyBR Green to investigate fox cytokine expression after antigen PBMC in vitro re-stimulation is presented here. First, we cloned by homology with dog cytokine sequences the fox IL2, IL6, IL10, IFNgamma and a partial 18S sequence. Fox specific primers were then defined and used to set up a species-specific quantitative RT-PCR assay using SyBR Green and 18S housekeeping gene as internal standard. The technique was validated using total RNA from fox PBMC stimulated with a polyclonal activator, Concanavaline A.

Pioneer factors, genetic competence, and inductive signaling: programming liver and pancreas progenitors from the endoderm.

PubMed

Zaret, K S; Watts, J; Xu, J; Wandzioch, E; Smale, S T; Sekiya, T

2008-01-01

The endoderm is a multipotent progenitor cell population in the embryo that gives rise to the liver, pancreas, and other cell types and provides paradigms for understanding cell-type specification. Studies of isolated embryo tissue cells and genetic approaches in vivo have defined fibroblast growth factor/mitogen-activated protein kinase (FGF/MAPK) and bone morphogenetic protein (BMP) signaling pathways that induce liver and pancreatic fates in the endoderm. In undifferentiated endoderm cells, the FoxA and GATA transcription factors are among the first to engage silent genes, helping to endow competence for cell-type specification. FoxA proteins can bind their target sites in highly compacted chromatin and open up the local region for other factors to bind; hence, they have been termed "pioneer factors." We recently found that FoxA proteins remain bound to chromatin in mitosis, as an epigenetic mark. In embryonic stem cells, which lack FoxA, FoxA target sites can be occupied by FoxD3, which in turn helps to maintain a local demethylation of chromatin. By these means, a cascade of Fox factors helps to endow progenitor cells with the competence to activate genes in response to tissue-inductive signals. Understanding such epigenetic mechanisms for transcriptional competence coupled with knowledge of the relevant signals for cell-type specification should greatly facilitate efforts to predictably differentiate stem cells to liver and pancreatic fates.

FGF21 protects human umbilical vein endothelial cells against high glucose-induced apoptosis via PI3K/Akt/Fox3a signaling pathway.

PubMed

Guo, Dongmin; Xiao, Lele; Hu, Huijun; Liu, Mihua; Yang, Lu; Lin, Xiaolong

2018-05-25

Diabetic macroangiopathy is the main cause of morbidity and mortality in patients with diabetes. Endothelial cell injury is a pathological precondition for diabetic macroangiopathy. Fibroblast growth factor 21 (FGF21) is a key metabolic regulator which has recently been suggested to protect cardiac myocytes and vascular cells against oxidative stress-induced injury in vitro and vivo. In this study, we aimed to investigate the protective capacity of FGF21 in human umbilical vein endothelial cells (HUVECs) against high glucose (HG)-induced apoptosis via phosphatidylinositol-3-kinase/protein kinase B (PI3K/Akt)/FoxO3a pathway. The cell viability was examined by CCK-8 assay, Intracellular ROS levels were measured by the detection of the fluorescent product formed by the oxidation of DCFH-DA, Apoptosis was analyzed using Hoechst 33258 nuclear staining and Flow Cytometry Analysis (FCA), the expression of protein were detected by Western blot. Results show that pretreating HUVECs with FGF21 before exposure to HG increases cell viability, while decreasing apoptosis and the generation of reactive oxygen species. Western blot analysis shows that HG reduces the phosphorylation of Akt and FoxO3a, and induces nuclear localization of FoxO3a. The effects were significantly reversed by FGF21 pre-treatment. Furthermore, the protective effects of FGF21 were prevented by PI3K/Akt inhibitor LY294002. Our data demonstrates that FGF21 protects HUVECs from HG-induced oxidative stress and apoptosis via the activation of PI3K/Akt/FoxO3a signaling pathway. Copyright © 2018 Elsevier Inc. All rights reserved.

FoxO1-negative cells are cancer stem-like cells in pancreatic ductal adenocarcinoma.

PubMed

Song, Weifeng; Li, Qi; Wang, Lei; Huang, Weiyi; Wang, Liwei

2015-06-11

Flow cytometry assays using aldehyde dehydrogenase (ALDH) activity or CD133 positivity to isolate cancer stem cells (CSCs) are widely applied but have limitations. Thus, characterization of CSC makers for a specific cancer is potentially important. We have previously shown that miR-21 regulates cancer cell growth via FoxO1 in pancreatic ductal adenocarcinoma (PDAC). Here, we areported evidence of FoxO1-negative PDAC cells as CSCs in PDAC. Both ALDH-high and CD133-high cell fractions isolated from PDAC of the patients expressed high levels of miR-21 and null FoxO1. Cultured PDAC cells were virally transduced with GFP under FoxO1 promoter. GFP (FoxO1)-null PDAC cells expressed high levels of miR-21, and grew more quickly than FoxO1-positive PDAC cells. Moreover, the fold increases in growth of FoxO1-negative vs FoxO1-positive cells were greater than CD133-high vs CD133-low cells, or ALDH-high vs ALDH-low cells. Further, FoxO1-negative cells formed tumor spheres in culture and developed tumors after serial adoptive transplantation into NOD/SCID mice, while the FoxO1-positive cells did not. Finally, selective elimination of FoxO1-negative cells completely inhibited the growth of PDAC cells. Together, these data suggest that FoxO1-negative cells as CSCs in PDAC, and targeting FoxO1-negative cells in PDAC may provide better therapeutic outcome.

Mapping the distribution of language related genes FoxP1, FoxP2, and CntnaP2 in the brains of vocal learning bat species.

PubMed

Rodenas-Cuadrado, Pedro M; Mengede, Janine; Baas, Laura; Devanna, Paolo; Schmid, Tobias A; Yartsev, Michael; Firzlaff, Uwe; Vernes, Sonja C

2018-06-01

Genes including FOXP2, FOXP1, and CNTNAP2, have been implicated in human speech and language phenotypes, pointing to a role in the development of normal language-related circuitry in the brain. Although speech and language are unique to humans a comparative approach is possible by addressing language-relevant traits in animal systems. One such trait, vocal learning, represents an essential component of human spoken language, and is shared by cetaceans, pinnipeds, elephants, some birds and bats. Given their vocal learning abilities, gregarious nature, and reliance on vocalizations for social communication and navigation, bats represent an intriguing mammalian system in which to explore language-relevant genes. We used immunohistochemistry to detail the distribution of FoxP2, FoxP1, and Cntnap2 proteins, accompanied by detailed cytoarchitectural histology in the brains of two vocal learning bat species; Phyllostomus discolor and Rousettus aegyptiacus. We show widespread expression of these genes, similar to what has been previously observed in other species, including humans. A striking difference was observed in the adult P. discolor bat, which showed low levels of FoxP2 expression in the cortex that contrasted with patterns found in rodents and nonhuman primates. We created an online, open-access database within which all data can be browsed, searched, and high resolution images viewed to single cell resolution. The data presented herein reveal regions of interest in the bat brain and provide new opportunities to address the role of these language-related genes in complex vocal-motor and vocal learning behaviors in a mammalian model system. © 2018 The Authors The Journal of Comparative Neurology Published by Wiley Periodicals, Inc.

Mapping the distribution of language related genes FoxP1, FoxP2, and CntnaP2 in the brains of vocal learning bat species

PubMed Central

Rodenas‐Cuadrado, Pedro M.; Mengede, Janine; Baas, Laura; Devanna, Paolo; Schmid, Tobias A.; Yartsev, Michael; Firzlaff, Uwe

2018-01-01

Abstract Genes including FOXP2, FOXP1, and CNTNAP2, have been implicated in human speech and language phenotypes, pointing to a role in the development of normal language‐related circuitry in the brain. Although speech and language are unique to humans a comparative approach is possible by addressing language‐relevant traits in animal systems. One such trait, vocal learning, represents an essential component of human spoken language, and is shared by cetaceans, pinnipeds, elephants, some birds and bats. Given their vocal learning abilities, gregarious nature, and reliance on vocalizations for social communication and navigation, bats represent an intriguing mammalian system in which to explore language‐relevant genes. We used immunohistochemistry to detail the distribution of FoxP2, FoxP1, and Cntnap2 proteins, accompanied by detailed cytoarchitectural histology in the brains of two vocal learning bat species; Phyllostomus discolor and Rousettus aegyptiacus. We show widespread expression of these genes, similar to what has been previously observed in other species, including humans. A striking difference was observed in the adult P. discolor bat, which showed low levels of FoxP2 expression in the cortex that contrasted with patterns found in rodents and nonhuman primates. We created an online, open‐access database within which all data can be browsed, searched, and high resolution images viewed to single cell resolution. The data presented herein reveal regions of interest in the bat brain and provide new opportunities to address the role of these language‐related genes in complex vocal‐motor and vocal learning behaviors in a mammalian model system. PMID:29297931

The role of class I histone deacetylase (HDAC) on gluconeogenesis in liver

DOE Office of Scientific and Technical Information (OSTI.GOV)

Oiso, Hiroshi; Furukawa, Noboru, E-mail: n-furu@gpo.kumamoto-u.ac.jp; Suefuji, Mihoshi

2011-01-07

Research highlights: {yields} A novel class I HDAC inhibitor decreased hepatic PEPCK mRNA and gluconeogenesis. {yields} Inhibition of HDAC decreased PEPCK by reducing HNF4{alpha} expression and FoxO1 activity. {yields} siRNA knockdown of HDAC1 in HepG2 cells reduced the expression of PEPCK and HNF4{alpha}. {yields} Inhibition of class I HDAC improves glucose homeostasis in HFD mice. -- Abstract: Hepatic gluconeogenesis is crucial for glucose homeostasis. Although sirtuin 1 (Sirt1) is implicated in the regulation of gluconeogenesis in the liver, the effects of other histone deacetylases (HDAC) on gluconeogenesis are unclear. The aim of this study was to identify the role ofmore » class I HDACs in hepatic gluconeogenesis. In HepG2 cells and the liver of mice, the expressions of phosphoenol pyruvate carboxykinase (PEPCK) and hepatocyte nuclear factor 4{alpha} (HNF4{alpha}) were significantly decreased by treatment with a newly designed class I HDAC inhibitor, Ky-2. SiRNA knockdown of HDAC1 expression, but not of HDAC2 or HDAC3, in HepG2 cells decreased PEPCK and HNF4{alpha} expression. In HepG2 cells, insulin-stimulated phosphorylation of Akt and forkhead box O 1 (FoxO1) was increased by Ky-2. Pyruvate tolerance tests in Ky-2-treated high-fat-diet (HFD)-fed mice showed a marked reduction in blood glucose compared with vehicle-treated HFD mice. These data suggest that class I HDACs increase HNF4{alpha} protein expression and the transcriptional activity of FoxO1, followed by the induction of PEPCK mRNA expression and gluconeogenesis in liver.« less

Impaired Akt phosphorylation in B-cells of patients with common variable immunodeficiency.

PubMed

Yazdani, Reza; Ganjalikhani-Hakemi, Mazdak; Esmaeili, Mohammad; Abolhassani, Hassan; Vaeli, Shahram; Rezaei, Abbas; Sharifi, Zohre; Azizi, Gholamreza; Rezaei, Nima; Aghamohammadi, Asghar

2017-02-01

Common variable immunodeficiency (CVID) is a heterogeneous group of primary immunodeficiency characterized by recurrent infections. We evaluated whether defective PI3K/Akt/FoxO pathway could influence B-cell fate. Determination of B-cell subsets in CVD patients and healthy donors (HDs) were performed using flow cytometry. We evaluated mRNA and protein expression of PI3K, Akt and FoxO using real-time PCR and flow cytometry, respectively. Moreover, phosphorylated Akt (pAkt) expression in B-cells has been measured by flowcytometry. We identified a significant reduction in the percentage of marginal zone like B-cells, memory B-cells (total, switched and unswitched) and plasmablasts in patients, as these decreased B-cell subsets had a significant negative correlation with increased apoptosis in patients. Surprisingly, we identified decreased pAkt expression in B-cells of patients than HDs. We described for the first time impaired pAkt expression in B-cells of CVID patients that had a significant correlation with antibody response to the vaccine and worse clinical complications. Copyright © 2016 Elsevier Inc. All rights reserved.

Nonoverlapping roles of PD-1 and FoxP3 in maintaining immune tolerance in a novel autoimmune pancreatitis mouse model.

PubMed

Zhang, Baihao; Chikuma, Shunsuke; Hori, Shohei; Fagarasan, Sidonia; Honjo, Tasuku

2016-07-26

PD-1 (programmed-death 1), an immune-inhibitory receptor required for immune self-tolerance whose deficiency causes autoimmunity with variable severity and tissue specificity depending on other genetic factors, is expressed on activated T cells, including the transcription factor FoxP3(+) Treg cells known to play critical roles in maintaining immune tolerance. However, whether PD-1 expression by the Treg cells is required for their immune regulatory function, especially in autoimmune settings, is still unclear. We found that mice with partial FoxP3 insufficiency developed early-onset lympho-proliferation and lethal autoimmune pancreatitis only when PD-1 is absent. The autoimmune phenotype was rescued by the transfer of FoxP3-sufficient T cells, regardless of whether they were derived from WT or PD-1-deficient mice, indicating that Treg cells dominantly protect against development of spontaneous autoimmunity without intrinsic expression of PD-1. The absence of PD-1 combined with partial FoxP3 insufficiency, however, led to generation of ex-FoxP3 T cells with proinflammatory properties and expansion of effector/memory T cells that contributed to the autoimmune destruction of target tissues. Altogether, the results suggest that PD-1 and FoxP3 work collaboratively in maintaining immune tolerance mostly through nonoverlapping pathways. Thus, PD-1 is modulating the activation threshold and maintaining the balance between regulatory and effector T cells, whereas FoxP3 is sufficient for dominant regulation through maintaining the integrity of the Treg function. We suggest that genetic or environmental factors that even moderately affect the expression of both PD-1 and FoxP3 can cause life-threatening autoimmune diseases by disrupting the T-cell homeostasis.

Nonoverlapping roles of PD-1 and FoxP3 in maintaining immune tolerance in a novel autoimmune pancreatitis mouse model

PubMed Central

Zhang, Baihao; Chikuma, Shunsuke; Hori, Shohei; Fagarasan, Sidonia; Honjo, Tasuku

2016-01-01

PD-1 (programmed-death 1), an immune-inhibitory receptor required for immune self-tolerance whose deficiency causes autoimmunity with variable severity and tissue specificity depending on other genetic factors, is expressed on activated T cells, including the transcription factor FoxP3+ Treg cells known to play critical roles in maintaining immune tolerance. However, whether PD-1 expression by the Treg cells is required for their immune regulatory function, especially in autoimmune settings, is still unclear. We found that mice with partial FoxP3 insufficiency developed early-onset lympho-proliferation and lethal autoimmune pancreatitis only when PD-1 is absent. The autoimmune phenotype was rescued by the transfer of FoxP3-sufficient T cells, regardless of whether they were derived from WT or PD-1–deficient mice, indicating that Treg cells dominantly protect against development of spontaneous autoimmunity without intrinsic expression of PD-1. The absence of PD-1 combined with partial FoxP3 insufficiency, however, led to generation of ex-FoxP3 T cells with proinflammatory properties and expansion of effector/memory T cells that contributed to the autoimmune destruction of target tissues. Altogether, the results suggest that PD-1 and FoxP3 work collaboratively in maintaining immune tolerance mostly through nonoverlapping pathways. Thus, PD-1 is modulating the activation threshold and maintaining the balance between regulatory and effector T cells, whereas FoxP3 is sufficient for dominant regulation through maintaining the integrity of the Treg function. We suggest that genetic or environmental factors that even moderately affect the expression of both PD-1 and FoxP3 can cause life-threatening autoimmune diseases by disrupting the T-cell homeostasis. PMID:27410049

Systemic AA amyloidosis in the red fox (Vulpes vulpes).

PubMed

Rising, Anna; Cederlund, Ella; Palmberg, Carina; Uhlhorn, Henrik; Gaunitz, Stefan; Nordling, Kerstin; Ågren, Erik; Ihse, Elisabet; Westermark, Gunilla T; Tjernberg, Lars; Jörnvall, Hans; Johansson, Jan; Westermark, Per

2017-11-01

Amyloid A (AA) amyloidosis occurs spontaneously in many mammals and birds, but the prevalence varies considerably among different species, and even among subgroups of the same species. The Blue fox and the Gray fox seem to be resistant to the development of AA amyloidosis, while Island foxes have a high prevalence of the disease. Herein, we report on the identification of AA amyloidosis in the Red fox (Vulpes vulpes). Edman degradation and tandem MS analysis of proteolyzed amyloid protein revealed that the amyloid partly was composed of full-length SAA. Its amino acid sequence was determined and found to consist of 111 amino acid residues. Based on inter-species sequence comparisons we found four residue exchanges (Ser31, Lys63, Leu71, Lys72) between the Red and Blue fox SAAs. Lys63 seems unique to the Red fox SAA. We found no obvious explanation to how these exchanges might correlate with the reported differences in SAA amyloidogenicity. Furthermore, in contrast to fibrils from many other mammalian species, the isolated amyloid fibrils from Red fox did not seed AA amyloidosis in a mouse model. © 2017 The Protein Society.

Complete Mitochondrial Genome of the Red Fox (Vuples vuples) and Phylogenetic Analysis with Other Canid Species.

PubMed

Zhong, Hua-Ming; Zhang, Hong-Hai; Sha, Wei-Lai; Zhang, Cheng-De; Chen, Yu-Cai

2010-04-01

The whole mitochondrial genome sequence of red fox (Vuples vuples) was determined. It had a total length of 16 723 bp. As in most mammal mitochondrial genome, it contained 13 protein coding genes, two ribosome RNA genes, 22 transfer RNA genes and one control region. The base composition was 31.3% A, 26.1% C, 14.8% G and 27.8% T, respectively. The codon usage of red fox, arctic fox, gray wolf, domestic dog and coyote followed the same pattern except for an unusual ATT start codon, which initiates the NADH dehydrogenase subunit 3 gene in the red fox. A long tandem repeat rich in AC was found between conserved sequence block 1 and 2 in the control region. In order to confirm the phylogenetic relationships of red fox to other canids, phylogenetic trees were reconstructed by neighbor-joining and maximum parsimony methods using 12 concatenated heavy-strand protein-coding genes. The result indicated that arctic fox was the sister group of red fox and they both belong to the red fox-like clade in family Canidae, while gray wolf, domestic dog and coyote belong to wolf-like clade. The result was in accordance with existing phylogenetic results.

The forkhead transcription factor FoxY regulates Nanos

PubMed Central

Song, Jia L.; Wessel, Gary M.

2012-01-01

FoxY is a member of the forkhead transcription factor family that appeared enriched in the presumptive germ line of sea urchins (Ransick et al., 2002, Dev Biol 246:132). Here we test the hypothesis that FoxY is involved in germ line determination in this animal. We found two splice forms of FoxY that share the same DNA-binding domain but vary in the carboxy-terminal trans-activation/repression domain. Both forms of the FoxY protein are present in the ovary and in the early embryo, and their mRNAs accumulate to their highest levels in the small micromeres and adjacent non-skeletogenic mesoderm. Knockdown of FoxY resulted in a dramatic decrease in the Nanos mRNA and protein levels as well as a loss of coelomic pouches in the 2-week-old larvae. Our results indicate that FoxY positively regulates Nanos at the transcriptional level and is essential for reproductive potential in this organism. PMID:22777754

The forkhead transcription factor FoxY regulates Nanos.

PubMed

Song, Jia L; Wessel, Gary M

2012-10-01

FoxY is a member of the forkhead transcription factor family that appeared enriched in the presumptive germ line of sea urchins (Ransick et al. Dev Biol 2002;246:132). Here, we test the hypothesis that FoxY is involved in germ line determination in this animal. We found two splice forms of FoxY that share the same DNA-binding domain, but vary in the carboxy-terminal trans-activation/repression domain. Both forms of the FoxY protein are present in the egg and in the early embryo, and their mRNAs accumulate to their highest levels in the small micromeres and adjacent non-skeletogenic mesoderm. Knockdown of FoxY resulted in a dramatic decrease in Nanos mRNA and protein levels as well as a loss of coelomic pouches in 2-week-old larvae. Our results indicate that FoxY positively regulates Nanos at the transcriptional level and is essential for reproductive potential in this organism. Copyright © 2012 Wiley Periodicals, Inc.

Molecular epidemiology of rabies in northern Colombia 1994-2003. Evidence for human and fox rabies associated with dogs.

PubMed Central

Páez, A.; Saad, C.; Núñez, C.; Bóshell, J.

2005-01-01

During the period 2000-2003, wild grey foxes (Urocyon cinereoargenteus) in northern Colombia became infected with rabies. In order to derive phylogenetic relationships between rabies viruses isolated in foxes, dogs and humans in this region, 902 nt cDNA fragments containing the G-L intergenic region and encoding the cytoplasmic domain of protein G and a fragment of protein L were obtained by RT-PCR, sequenced and compared. Phylogenetic analysis showed that rabies viruses isolated in foxes, dogs and humans belonged to a single genetic variant. Speculative analysis together with epidemiological data indicated that rabies in foxes may have been due to contact with rabid dogs. Rabies transmission between dogs, wild foxes and humans may happen in natural conditions in northern Colombia. This finding is the first to suggest dog-to-fox rabies transmission in South America, and provides another example of dog rabies variants being able to successfully colonize wildlife hosts. PMID:15962560

Atomoxetine Prevents Dexamethasone-Induced Skeletal Muscle Atrophy in Mice

PubMed Central

Jesinkey, Sean R.; Korrapati, Midhun C.; Rasbach, Kyle A.; Beeson, Craig C.

2014-01-01

Skeletal muscle atrophy remains a clinical problem in numerous pathologic conditions. β2-Adrenergic receptor agonists, such as formoterol, can induce mitochondrial biogenesis (MB) to prevent such atrophy. Additionally, atomoxetine, an FDA-approved norepinephrine reuptake inhibitor, was positive in a cellular assay for MB. We used a mouse model of dexamethasone-induced skeletal muscle atrophy to investigate the potential role of atomoxetine and formoterol to prevent muscle mass loss. Mice were administered dexamethasone once daily in the presence or absence of formoterol (0.3 mg/kg), atomoxetine (0.1 mg/kg), or sterile saline. Animals were euthanized at 8, 16, and 24 hours or 8 days later. Gastrocnemius muscle weights, changes in mRNA and protein expression of peroxisome proliferator–activated receptor-γ coactivator-1 α (PGC-1α) isoforms, ATP synthase β, cytochrome c oxidase subunit I, NADH dehydrogenase (ubiquinone) 1 β subcomplex, 8, ND1, insulin-like growth factor 1 (IGF-1), myostatin, muscle Ring-finger protein-1 (muscle atrophy), phosphorylated forkhead box protein O 3a (p-FoxO3a), Akt, mammalian target of rapamycin (mTOR), and ribosomal protein S6 (rp-S6; muscle hypertrophy) in naive and muscle-atrophied mice were measured. Atomoxetine increased p-mTOR 24 hours after treatment in naïve mice, but did not change any other biomarkers. Formoterol robustly activated the PGC-1α-4-IGF1–Akt-mTOR-rp-S6 pathway and increased p-FoxO3a as early as 8 hours and repressed myostatin at 16 hours. In contrast to what was observed with acute treatment, chronic treatment (7 days) with atomoxetine increased p-Akt and p-FoxO3a, and sustained PGC-1α expression and skeletal muscle mass in dexamethasone-treated mice, in a manner comparable to formoterol. In conclusion, chronic treatment with a low dose of atomoxetine prevented dexamethasone-induced skeletal muscle wasting and supports a potential role in preventing muscle atrophy. PMID:25292181

Critical Role of AMPK/FoxO3A Axis in Globular Adiponectin-Induced Cell Cycle Arrest and Apoptosis in Cancer Cells.

PubMed

Shrestha, Anup; Nepal, Saroj; Kim, Mi Jin; Chang, Jae Hoon; Kim, Sang-Hyun; Jeong, Gil-Saeng; Jeong, Chul-Ho; Park, Gyu Hwan; Jung, Sunghee; Lim, Jaecheong; Cho, Eunha; Lee, Soyoung; Park, Pil-Hoon

2016-02-01

Adiponectin predominantly secreted from adipose tissue has exhibited potent anti-proliferative properties in cancer cells via modulating cell cycle and apoptosis. FoxO3A, a Forkhead box O member of the transcription factor, plays a critical role in modulating expression of genes involved in cell death and/or survival. In this study, we investigated the role of FoxO3A signaling in anti-cancer activities of adiponectin. Herein, we have shown that treatment with globular adiponectin (gAcrp) increases p27 but decreases cyclinD1 expression in human hepatoma (HepG2) and breast (MCF-7) cancer cells. Gene ablation of FoxO3A prevented gAcrp-induced increase in p27 and decreased in cyclin D1 expression, and further ameliorated cell cycle arrest by gAcrp, indicating a critical role of FoxO3A in gAcrp-induced cell cycle arrest of cancer cells. Moreover, treatment with gAcrp also induced caspase-3/7 activation and increased Fas ligand (FasL) expression in both HepG2 and MCF-7 cells. Transfection with FoxO3A siRNA inhibited gAcrp-induced caspase-3/7 activation and FasL expression, suggesting that FoxO3A signaling also plays an important role in gAcrp-induced apoptosis of cancer cells. We also found that gene silencing of AMPK prevented gAcrp-induced nuclear translocation of FoxO3A in HepG2 and MCF-7 cells. In addition, suppression of AMPK also blocked gAcrp-induced cell cycle arrest and further attenuated gAcrp-induced caspase-3/7 activation, indicating that AMPK signaling plays a pivotal role in both gAcrp-induced cell cycle arrest and apoptosis via acting as an upstream signaling of FoxO3A. Taken together, our findings demonstrated that AMPK/FoxO3A axis plays a cardinal role in anti-proliferative effect of adiponectin in cancer cells. © 2015 Wiley Periodicals, Inc.

Fox-2 protein regulates the alternative splicing of scleroderma-associated lysyl hydroxylase 2 messenger RNA.

PubMed

Seth, Puneet; Yeowell, Heather N

2010-04-01

Scleroderma (systemic sclerosis [SSc]) is a complex connective tissue disorder characterized by hardening and thickening of the skin. One hallmark of scleroderma is excessive accumulation of collagen accompanied by increased levels of pyridinoline collagen crosslinks derived from hydroxylysine residues in the collagen telopeptide domains. Lysyl hydroxylase 2 (LH2), an important alternatively spliced enzyme in collagen biosynthesis, acts as a collagen telopeptide hydroxylase. Changes in the pattern of LH2 alternative splicing, favoring increased inclusion of the alternatively spliced LH2 exon 13A, thereby increasing the levels of the long transcript of LH2 (LH2[long]), are linked to scleroderma disease. This study was undertaken to examine the role played by RNA binding protein Fox-2 in regulating exon 13A inclusion, which leads to the generation of scleroderma-associated LH2(long) messenger RNA (mRNA). Phylogenetic sequence analysis of introns flanking exon 13A was performed. A tetracycline-inducible system in T-Rex 293 cells was used to induce Fox-2 protein, and endogenous LH2(long) mRNA was determined by reverse transcriptase-polymerase chain reaction. An LH2 minigene was designed, validated, and used in Fox-2 overexpression and mutagenesis experiments. Knockdown of Fox-2 was performed in mouse embryonic fibroblasts and in fibroblasts from SSc patients. Overexpression of Fox-2 enhanced the inclusion of exon 13A and increased the generation of LH2(long) mRNA, whereas knockdown of Fox-2 decreased LH2(long) transcripts. Mutational analysis of an LH2 minigene demonstrated that 2 of the 4 Fox binding motifs flanking LH2 exon 13A are required for inclusion of exon 13A. In early passage fibroblasts derived from patients with scleroderma, the knockdown of Fox-2 protein significantly decreased the endogenous levels of LH2(long) mRNA. Our findings indicate that Fox-2 plays an integral role in the regulation of LH2 splicing. Knockdown of Fox-2 and other methods to decrease the levels of fibrosis-associated LH2(long) mRNA in primary scleroderma cells may suggest a novel approach to strategies directed against scleroderma.

Lithium ions attenuate serum-deprivation-induced apoptosis in PC12 cells through regulation of the Akt/FoxO1 signaling pathways.

PubMed

Zeng, Zhiwen; Wang, Haitao; Shang, Fu; Zhou, Lihua; Little, Peter J; Quirion, Remi; Zheng, Wenhua

2016-03-01

Lithium is currently used in the treatment of mental illness. We have previously reported that lithium stimulated the protein kinase B/Forkhead box O1 (Akt/FoxO1) pathway in rats. However, little information is available regarding its neuroprotective role of this pathway and underlying mechanisms. PC12 cells treated with serum deprivation were used as a toxicity model to study the protective effect of lithium and its underlying mechanisms. Cell viability was determined by methyl thiazolyl tetrazolium assay and Hoechst staining. FoxO1 subcellular location and its overexpression were used to study the underlying mechanisms. Various pathway inhibitors were used to investigate the possible pathways, while the phosphorylation of Akt and FoxO1 was analyzed by Western blot. Lithium pretreatment dose-dependently reduced PC12 cell apoptosis induced by serum starvation. The protective effect of lithium was abolished by LY294002, a PI3K-specific inhibitor, and Akt inhibitor Akt inhibitor VIII, whereas mitogen-activated protein kinase kinase (MEK kinase) inhibitor U0126 had no effect. Lithium induced the phosphorylation of Akt and FoxO1 in a time- and concentration-dependent manner. Lithium-induced phosphorylation of Akt and FoxO1 is mediated by the PI3K/Akt pathway. Serum deprivation caused nuclear translocation of FoxO1 while application of lithium reversed the effect of serum deprivation. Moreover, overexpression of FoxO1 enhanced cell apoptosis induced by serum withdrawal. Finally, lithium was found to reduce the exogenous and endogenous FoxO1 protein levels in PC12 cells in a concentration-dependent fashion. The protective effect of lithium against serum starvation cell death is mediated by the PI3K/Akt/FoxO1 pathway.

FoxO1 in dopaminergic neurons regulates energy homeostasis and targets tyrosine hydroxylase

PubMed Central

Doan, Khanh V.; Kinyua, Ann W.; Yang, Dong Joo; Ko, Chang Mann; Moh, Sang Hyun; Shong, Ko Eun; Kim, Hail; Park, Sang-Kyu; Kim, Dong-Hoon; Kim, Inki; Paik, Ji-Hye; DePinho, Ronald A.; Yoon, Seul Gi; Kim, Il Yong; Seong, Je Kyung; Choi, Yun-Hee; Kim, Ki Woo

2016-01-01

Dopaminergic (DA) neurons are involved in the integration of neuronal and hormonal signals to regulate food consumption and energy balance. Forkhead transcriptional factor O1 (FoxO1) in the hypothalamus plays a crucial role in mediation of leptin and insulin function. However, the homoeostatic role of FoxO1 in DA system has not been investigated. Here we report that FoxO1 is highly expressed in DA neurons and mice lacking FoxO1 specifically in the DA neurons (FoxO1 KODAT) show markedly increased energy expenditure and interscapular brown adipose tissue (iBAT) thermogenesis accompanied by reduced fat mass and improved glucose/insulin homoeostasis. Moreover, FoxO1 KODAT mice exhibit an increased sucrose preference in concomitance with higher dopamine and norepinephrine levels. Finally, we found that FoxO1 directly targets and negatively regulates tyrosine hydroxylase (TH) expression, the rate-limiting enzyme of the catecholamine synthesis, delineating a mechanism for the KO phenotypes. Collectively, these results suggest that FoxO1 in DA neurons is an important transcriptional factor that directs the coordinated control of energy balance, thermogenesis and glucose homoeostasis. PMID:27681312

AmphiFoxQ2, a novel winged helix/forkhead gene, exclusively marks the anterior end of the amphioxus embryo

NASA Technical Reports Server (NTRS)

Yu, Jr-Kai; Holland, Nicholas D.; Holland, Linda Z.

2003-01-01

A full-length FoxQ-related gene (AmphiFoxQ2) was isolated from amphioxus. Expression is first detectable in the animal/anterior hemisphere at the mid blastula stage. The midpoint of this expression domain coincides with the anterior pole of the embryo and is offset dorsally by about 20 degrees from the animal pole. During the gastrula stage, expression is limited to the anterior ectoderm. By the early neurula stage, expression remains in the anterior ectoderm and also appears in the adjacent anterior mesendoderm. By the early larval stages, expression is detectable in the anteriormost ectoderm and in the rostral tip of the notochord. AmphiFoxQ2 is never expressed anywhere except at the anterior tip of amphioxus embryos and larvae. This is the first gene known that exclusively marks the anterior pole of chordate embryos. It may, therefore, play an important role in establishing and/or maintaining the anterior/posterior axis.

The type I BMP receptors, Bmpr1a and Acvr1, activate multiple signaling pathways to regulate lens formation

PubMed Central

Rajagopal, Ramya; Huang, Jie; Dattilo, Lisa K.; Kaartinen, Vesa; Mishina, Yuji; Deng, Chu-Xia; Umans, Lieve; Zwijsen, An; Roberts, Anita B.; Beebe, David C.

2009-01-01

BMPs play multiple roles in development and BMP signaling is essential for lens formation. However, the mechanisms by which BMP receptors function in vertebrate development are incompletely understood. To determine the downstream effectors of BMP signaling and their functions in the ectoderm that will form the lens, we deleted the genes encoding the type I BMP receptors, Bmpr1a and Acvr1, and the canonical transducers of BMP signaling, Smad4, Smad1 and Smad5. Bmpr1a and Acvr1 regulated cell survival and proliferation, respectively. Absence of both receptors interfered with the expression of proteins involved in normal lens development and prevented lens formation, demonstrating that BMPs induce lens formation by acting directly on the prospective lens ectoderm. Remarkably, the canonical Smad signaling pathway was not needed for most of these processes. Lens formation, placode cell proliferation, the expression of FoxE3, a lens-specific transcription factor, and the lens protein, αA-crystallin were regulated by BMP receptors in a Smad-independent manner. Placode cell survival was promoted by R-Smad signaling, but in a manner that did not involve Smad4. Of the responses tested, only maintaining a high level of Sox2 protein, a transcription factor expressed early in placode formation, required the canonical Smad pathway. A key function of Smad-independent BMP receptor signaling may be reorganization of actin cytoskeleton to drive lens invagination. PMID:19733164

FoxP2 brainstem neurons project to sodium appetite regulatory sites.

PubMed

Shin, Jung-Won; Geerling, Joel C; Stein, Matthew K; Miller, Rebecca L; Loewy, Arthur D

2011-09-01

The transcription factor Forkhead box protein 2 (FoxP2) is expressed in two cell groups of the brainstem that have been implicated in sodium appetite regulation: the pre-locus coeruleus (pre-LC) and parabrachial nucleus--external lateral-inner subdivision (PBel-inner). Because the connections of these two groups are unknown, neuroanatomical tracing methods were used to define their central projections. The pre-LC outputs were first analyzed using an anterograde axonal tracer--Phaseolus vulgaris leucoagglutinin (PHAL) to construct a brain map. Next, we examined whether the FoxP2 immunoreactive (FoxP2+) neurons of the pre-LC contribute to these projections using a retrograde neuronal tracer--cholera toxin β-subunit (CTb). CTb was injected into selected brain regions identified in the anterograde tracing study. One week later the rats were killed, and brainstem sections were processed by a double immunohistochemical procedure to determine whether the FoxP2+ neurons in the pre-LC and/or PBel-inner contained CTb. FoxP2+ pre-LC neurons project to: (1) ventral pallidum; (2) substantia innominata and bed nucleus of the stria terminalis; (3) paraventricular, central medial, parafascicular, and subparafascicular parvicellular thalamic nuclei; (4) paraventricular (PVH), lateral, perifornical, dorsomedial (DMH), and parasubthalamic hypothalamic nuclei; and (5) ventral tegmental area (VTA), periaqueductal gray matter (PAG), dorsal and central linear raphe nuclei. FoxP2+ PBel-inner neurons project to the PVH and DMH, with weaker connections to the LHA, VTA, and PAG. Both the pre-LC and PBel-inner project to central sites implicated in sodium appetite, and related issues, including foraging behavior, hedonic responses to salt intake, sodium balance, and cardiovascular regulation, are discussed. Copyright © 2011 Elsevier B.V. All rights reserved.

FoxG1 and TLE2 act cooperatively to regulate ventral telencephalon formation.

PubMed

Roth, Martin; Bonev, Boyan; Lindsay, Jennefer; Lea, Robert; Panagiotaki, Niki; Houart, Corinne; Papalopulu, Nancy

2010-05-01

FoxG1 is a conserved transcriptional repressor that plays a key role in the specification, proliferation and differentiation of the telencephalon, and is expressed from the earliest stages of telencephalic development through to the adult. How the interaction with co-factors might influence the multiplicity and diversity of FoxG1 function is not known. Here, we show that interaction of FoxG1 with TLE2, a Xenopus tropicalis co-repressor of the Groucho/TLE family, is crucial for regulating the early activity of FoxG1. We show that TLE2 is co-expressed with FoxG1 in the ventral telencephalon from the early neural plate stage and functionally cooperates with FoxG1 in an ectopic neurogenesis assay. FoxG1 has two potential TLE binding sites: an N-terminal eh1 motif and a C-terminal YWPMSPF motif. Although direct binding seems to be mediated by the N-terminal motif, both motifs appear important for functional synergism. In the neurogenesis assay, mutation of either motif abolishes functional cooperation of TLE2 with FoxG1, whereas in the forebrain deletion of both motifs renders FoxG1 unable to induce the ventral telencephalic marker Nkx2.1. Knocking down either FoxG1 or TLE2 disrupts the development of the ventral telencephalon, supporting the idea that endogenous TLE2 and FoxG1 work together to specify the ventral telencephalon.

FoxG1 and TLE2 act cooperatively to regulate ventral telencephalon formation

PubMed Central

Roth, Martin; Bonev, Boyan; Lindsay, Jennefer; Lea, Robert; Panagiotaki, Niki; Houart, Corinne; Papalopulu, Nancy

2010-01-01

FoxG1 is a conserved transcriptional repressor that plays a key role in the specification, proliferation and differentiation of the telencephalon, and is expressed from the earliest stages of telencephalic development through to the adult. How the interaction with co-factors might influence the multiplicity and diversity of FoxG1 function is not known. Here, we show that interaction of FoxG1 with TLE2, a Xenopus tropicalis co-repressor of the Groucho/TLE family, is crucial for regulating the early activity of FoxG1. We show that TLE2 is co-expressed with FoxG1 in the ventral telencephalon from the early neural plate stage and functionally cooperates with FoxG1 in an ectopic neurogenesis assay. FoxG1 has two potential TLE binding sites: an N-terminal eh1 motif and a C-terminal YWPMSPF motif. Although direct binding seems to be mediated by the N-terminal motif, both motifs appear important for functional synergism. In the neurogenesis assay, mutation of either motif abolishes functional cooperation of TLE2 with FoxG1, whereas in the forebrain deletion of both motifs renders FoxG1 unable to induce the ventral telencephalic marker Nkx2.1. Knocking down either FoxG1 or TLE2 disrupts the development of the ventral telencephalon, supporting the idea that endogenous TLE2 and FoxG1 work together to specify the ventral telencephalon. PMID:20356955

Genetic Predictors of Interindividual Variability in Hepatic CYP3A4 ExpressionS⃞

PubMed Central

Lamba, Vishal; Panetta, John C.; Strom, Stephen

2010-01-01

Variability in hepatic CYP3A4 cannot be explained by common CYP3A4 coding variants. We previously identified polymorphisms in pregnane X receptor (PXR) and ATP-binding cassette subfamily B member 1 (ABCB1) associated with CYP3A4 mRNA levels in small cohorts of human livers. However, the relative contributions of these genetic variations or of polymorphisms in other CYP3A4 regulators to variable CYP3A4 expression were not known. We phenotyped livers from white donors (n = 128) by quantitative real-time polymerase chain reaction for expression of CYP3A4, CYP3A5, and CYP3A7 and nine transcriptional regulators, coactivators, and corepressors. We resequenced hepatic nuclear factor-3-β (HNF3β, FoxA2), HNF4α, HNF3γ (FoxA3), nuclear receptor corepressor 2 (NCoR2), and regions of the CYP3A4 promoter and genotyped informative single-nucleotide polymorphisms in PXR and ABCB1 in the same livers. CYP3A4 mRNA was positively correlated with PXR and FoxA2 and negatively correlated with NCoR2 mRNA. A common silent polymorphism and a polymorphic trinucleotide (CCT) repeat in FoxA2 were associated with CYP3A4 expression. The transcriptional activity of the FoxA2 polymorphic CCT repeat alleles (wild-type, n = 14 and variant, n = 13, 15, and 19) when assayed by luciferase reporter transactivation assays was greatest for the wild-type repeat, with deviations from this number having decreased transcriptional activity. This corresponded with higher expression of FoxA2 mRNA and its targets PXR and CYP3A4 in human livers with (CCT) n = 14 genotypes. Multiple linear regression analysis was used to quantify the contributions of selected genetic polymorphisms to variable CYP3A4 expression. This approach identified sex and polymorphisms in FoxA2, HNF4α, FoxA3, PXR, ABCB1, and the CYP3A4 promoter that together explained as much as 24.6% of the variation in hepatic CYP3A4 expression. PMID:19934400

Type I neuregulin1α is a novel local mediator to suppress hepatic gluconeogenesis in mice

PubMed Central

Arai, Takatomo; Ono, Yumika; Arimura, Yujiro; Sayama, Keimon; Suzuki, Tomohiro; Shinjo, Satoko; Kanai, Mai; Abe, Shin-ichi; Semba, Kentaro; Goda, Nobuhito

2017-01-01

Neuregulin1 is an epidermal growth factor (EGF)-like domain-containing protein that has multiple isoforms and functions as a local mediator in the control of various cellular functions. Here we show that type I isoform of neuregulin1 with an α-type EGF-like domain (Nrg1α) is the major isoform in mouse liver and regulates hepatic glucose production. Forced expression of Nrg1α in mouse liver enhanced systemic glucose disposal and decreased hepatic glucose production with reduced fasting blood glucose levels. Nuclear forkhead box protein O1 (FoxO1) and its downstream targets, PEPCK and G6Pase, were suppressed in liver and isolated hepatocytes by Nrg1α overexpression. In contrast, silencing of Nrg1α enhanced glucose production with increased PEPCK and G6Pase expressions in cAMP/dexamethasone-stimulated hepatocytes. Mechanistically, the recombinant α-type EGF-like domain of NRG1α (rNRG1α) stimulated the ERBB3 signalling pathway in hepatocytes, resulting in decreased nuclear FoxO1 accumulation via activation of both the AKT and ERK pathways. In addition, acute treatment with rNRG1α also suppressed elevation of blood glucose levels after both glucose and pyruvate challenge. Although a liver-specific deletion of Nrg1 gene in mice showed little effect on systemic glucose metabolism, these results suggest that NRG1α have a novel regulatory function in hepatic gluconeogenesis by regulating the ERBB3-AKT/ERK-FoxO1 cascade. PMID:28218289

Dynamic and Differential Regulation of Stem Cell Factor FoxD3 in the Neural Crest Is Encrypted in the Genome

PubMed Central

Tan-Cabugao, Joanne; Sauka-Spengler, Tatjana; Bronner, Marianne E.

2012-01-01

The critical stem cell transcription factor FoxD3 is expressed by the premigratory and migrating neural crest, an embryonic stem cell population that forms diverse derivatives. Despite its important role in development and stem cell biology, little is known about what mediates FoxD3 activity in these cells. We have uncovered two FoxD3 enhancers, NC1 and NC2, that drive reporter expression in spatially and temporally distinct manners. Whereas NC1 activity recapitulates initial FoxD3 expression in the cranial neural crest, NC2 activity recapitulates initial FoxD3 expression at vagal/trunk levels while appearing only later in migrating cranial crest. Detailed mutational analysis, in vivo chromatin immunoprecipitation, and morpholino knock-downs reveal that transcription factors Pax7 and Msx1/2 cooperate with the neural crest specifier gene, Ets1, to bind to the cranial NC1 regulatory element. However, at vagal/trunk levels, they function together with the neural plate border gene, Zic1, which directly binds to the NC2 enhancer. These results reveal dynamic and differential regulation of FoxD3 in distinct neural crest subpopulations, suggesting that heterogeneity is encrypted at the regulatory level. Isolation of neural crest enhancers not only allows establishment of direct regulatory connections underlying neural crest formation, but also provides valuable tools for tissue specific manipulation and investigation of neural crest cell identity in amniotes. PMID:23284303

Does the visual system of the flying fox resemble that of primates? The distribution of calcium-binding proteins in the primary visual pathway of Pteropus poliocephalus.

PubMed

Ichida, J M; Rosa, M G; Casagrande, V A

2000-01-31

It has been proposed that flying foxes and echolocating bats evolved independently from early mammalian ancestors in such a way that flying foxes form one of the suborders most closely related to primates. A major piece of evidence offered in support of a flying fox-primate link is the highly developed visual system of flying foxes, which is theorized to be primate-like in several different ways. Because the calcium-binding proteins parvalbumin (PV) and calbindin (CB) show distinct and consistent distributions in the primate visual system, the distribution of these same proteins was examined in the flying fox (Pteropus poliocephalus) visual system. Standard immunocytochemical techniques reveal that PV labeling within the lateral geniculate nucleus (LGN) of the flying fox is sparse, with clearly labeled cells located only within layer 1, adjacent to the optic tract. CB labeling in the LGN is profuse, with cells labeled in all layers throughout the nucleus. Double labeling reveals that all PV+ cells also contain CB, and that these cells are among the largest in the LGN. In primary visual cortex (V1) PV and CB label different classes of non-pyramidal neurons. PV+ cells are found in all cortical layers, although labeled cells are found only rarely in layer I. CB+ cells are found primarily in layers II and III. The density of PV+ neuropil correlates with the density of cytochrome oxidase staining; however, no CO+ or PV+ or CB+ patches or blobs are found in V1. These results show that the distribution of calcium-binding proteins in the flying fox LGN is unlike that found in primates, in which antibodies for PV and CB label specific separate populations of relay cells that exist in different layers. Indeed, the pattern of calcium-binding protein distribution in the flying fox LGN is different from that reported in any other terrestrial mammal. Within V1 no PV+ patches, CO blobs, or patchy distribution of CB+ neuropil that might reveal interblobs characteristic of primate V1 are found; however, PV and CB are found in separate populations of non-pyramidal neurons. The types of V1 cells labeled with antibodies to PV and CB in all mammals examined including the flying fox suggest that the similarities in the cellular distribution of these proteins in cortex reflect the fact that this feature is common to all mammals.

FoxA4 favours notochord formation by inhibiting contiguous mesodermal fates and restricts anterior neural development in Xenopus embryos.

PubMed

Murgan, Sabrina; Castro Colabianchi, Aitana Manuela; Monti, Renato José; Boyadjián López, Laura Elena; Aguirre, Cecilia E; Stivala, Ernesto González; Carrasco, Andrés E; López, Silvia L

2014-01-01

In vertebrates, the embryonic dorsal midline is a crucial signalling centre that patterns the surrounding tissues during development. Members of the FoxA subfamily of transcription factors are expressed in the structures that compose this centre. Foxa2 is essential for dorsal midline development in mammals, since knock-out mouse embryos lack a definitive node, notochord and floor plate. The related gene foxA4 is only present in amphibians. Expression begins in the blastula -chordin and -noggin expressing centre (BCNE) and is later restricted to the dorsal midline derivatives of the Spemann's organiser. It was suggested that the early functions of mammalian foxa2 are carried out by foxA4 in frogs, but functional experiments were needed to test this hypothesis. Here, we show that some important dorsal midline functions of mammalian foxa2 are exerted by foxA4 in Xenopus. We provide new evidence that the latter prevents the respecification of dorsal midline precursors towards contiguous fates, inhibiting prechordal and paraxial mesoderm development in favour of the notochord. In addition, we show that foxA4 is required for the correct regionalisation and maintenance of the central nervous system. FoxA4 participates in constraining the prospective rostral forebrain territory during neural specification and is necessary for the correct segregation of the most anterior ectodermal derivatives, such as the cement gland and the pituitary anlagen. Moreover, the early expression of foxA4 in the BCNE (which contains precursors of the whole forebrain and most of the midbrain and hindbrain) is directly required to restrict anterior neural development.

Transcriptional regulation of FoxO3 gene by glucocorticoids in murine myotubes

PubMed Central

Kuo, Taiyi; Liu, Patty H.; Chen, Tzu-Chieh; Lee, Rebecca A.; New, Jenny; Zhang, Danyun; Lei, Cassandra; Chau, Andy; Tang, Yicheng; Cheung, Edna

2016-01-01

Glucocorticoids and FoxO3 exert similar metabolic effects in skeletal muscle. FoxO3 gene expression was increased by dexamethasone (Dex), a synthetic glucocorticoid, both in vitro and in vivo. In C2C12 myotubes the increased expression is due to, at least in part, the elevated rate of FoxO3 gene transcription. In the mouse FoxO3 gene, we identified three glucocorticoid receptor (GR) binding regions (GBRs): one being upstream of the transcription start site, −17kbGBR; and two in introns, +45kbGBR and +71kbGBR. Together, these three GBRs contain four 15-bp glucocorticoid response elements (GREs). Micrococcal nuclease (MNase) assay revealed that Dex treatment increased the sensitivity to MNase in the GRE of +45kbGBR and +71kbGBR upon 30- and 60-min Dex treatment, respectively. Conversely, Dex treatment did not affect the chromatin structure near the −17kbGBR, in which the GRE is located in the linker region. Dex treatment also increased histone H3 and/or H4 acetylation in genomic regions near all three GBRs. Moreover, using chromatin conformation capture (3C) assay, we showed that Dex treatment increased the interaction between the −17kbGBR and two genomic regions: one located around +500 bp and the other around +73 kb. Finally, the transcriptional coregulator p300 was recruited to all three GBRs upon Dex treatment. The reduction of p300 expression decreased FoxO3 gene expression and Dex-stimulated interaction between distinct genomic regions of FoxO3 gene identified by 3C. Overall, our results demonstrate that glucocorticoids activated FoxO3 gene transcription through multiple GREs by chromatin structural change and DNA looping. PMID:26758684

The prognostic role of CD68 and FoxP3 expression in patients with primary central nervous system lymphoma.

PubMed

Cho, Hyunsoo; Kim, Se Hoon; Kim, Soo-Jeong; Chang, Jong Hee; Yang, Woo Ick; Suh, Chang-Ok; Cheong, June-Won; Kim, Yu Ri; Lee, Jung Yeon; Jang, Ji Eun; Kim, Yundeok; Min, Yoo Hong; Kim, Jin Seok

2017-07-01

The prognostic role of CD68 and FoxP3 in primary central nervous system lymphoma (PCNSL) has not been evaluated. Thus, we examined the prognostic significance of CD68 and FoxP3 expression in tumor samples of 76 newly diagnosed immunocompetent PCNSL patients. All patients were treated initially with high-dose methotrexate (HD-MTX)-based chemotherapy, and 16 (21.1%) patients received upfront autologous stem cell transplantation (ASCT) consolidation. High expression of CD68 (>55 cells/high-power field) or FoxP3 (>15 cells/high-power field) was observed in 10 patients, respectively. High CD68 expression was associated with inferior overall survival (OS) and progression-free survival (PFS) in multivariate analysis (P = 0.023 and P = 0.021, respectively). In addition, we performed subgroup analysis based on upfront ASCT. High CD68 expression was also associated with inferior OS and PFS in multivariate analysis (P = 0.013 and P < 0.001, respectively) among patients who did not receive upfront ASCT (n = 60), but not in patients who received upfront ASCT. The expression of FoxP3 was not significantly associated with survival. Therefore, we identified a prognostic significance of high CD68 expression in PCNSL, which suggests a need for further clinical trials and biological studies on the role of PCNSL tumor microenvironment.

Skin expression of mammalian target of rapamycin and forkhead box transcription factor O1, and serum insulin-like growth factor-1 in patients with acne vulgaris and their relationship with diet.

PubMed

Agamia, N F; Abdallah, D M; Sorour, O; Mourad, B; Younan, D N

2016-06-01

Acne vulgaris is a multifactorial disorder of the pilosebaceous units. Several studies have reported that insulin-like growth factor (IGF)-1, forkhead box transcription factor (Fox)O1 and mammalian target of rapamycin (mTOR) interactions may be the key to understanding the links between genetic and environmental factors in acne vulgaris. To evaluate the immunohistochemical detection of mTOR and FoxO1 in the skin, and the serum level of IGF-1 in patients with acne vulgaris. This study was carried out on 60 participants, including 40 patients with acne and 20 controls. A diet questionnaire was administered to the patients and controls. Serum levels of IGF-1 were measured using enzyme-linked immunosorbent assay, and skin biopsies were taken from lesions on the backs of the patients and controls. FoxO1 and mTOR expression was detected using immunohistochemistry. A significantly higher serum IGF-1 level was found in the patients with acne than in the controls. The cytoplasmic expression of FoxO1 was found to be significantly greater in the acne group, whereas in the control subjects this expression was likely to be nuclear. Both the cytoplasmic expression and the nuclear expression of mTOR were significantly more intense in the patients with acne than in the controls. Excess consumption of a high-glycaemic-load diet was significantly associated with higher serum levels of IGF-1 and cytoplasmic expression of FoxO1 and mTOR. These results suggest that FoxO1, mTOR, serum IGF-1 and a high-glycaemic-load diet may play a role in acne pathogenesis. © 2016 British Association of Dermatologists.

Activation of FoxM1 Revitalizes the Replicative Potential of Aged β-Cells in Male Mice and Enhances Insulin Secretion

PubMed Central

Golson, Maria L.; Dunn, Jennifer C.; Maulis, Matthew F.; Dadi, Prasanna K.; Osipovich, Anna B.; Magnuson, Mark A.; Jacobson, David A.

2015-01-01

Type 2 diabetes incidence increases with age, while β-cell replication declines. The transcription factor FoxM1 is required for β-cell replication in various situations, and its expression declines with age. We hypothesized that increased FoxM1 activity in aged β-cells would rejuvenate proliferation. Induction of an activated form of FoxM1 was sufficient to increase β-cell mass and proliferation in 12-month-old male mice after just 2 weeks. Unexpectedly, at 2 months of age, induction of activated FoxM1 in male mice improved glucose homeostasis with unchanged β-cell mass. Cells expressing activated FoxM1 demonstrated enhanced glucose-stimulated Ca2+ influx, which resulted in improved glucose tolerance through enhanced β-cell function. Conversely, our laboratory has previously demonstrated that mice lacking FoxM1 in the pancreas display glucose intolerance or diabetes with only a 60% reduction in β-cell mass, suggesting that the loss of FoxM1 is detrimental to β-cell function. Ex vivo insulin secretion was therefore examined in size-matched islets from young mice lacking FoxM1 in β-cells. Foxm1-deficient islets indeed displayed reduced insulin secretion. Our studies reveal that activated FoxM1 increases β-cell replication while simultaneously enhancing insulin secretion and improving glucose homeostasis, making FoxM1 an attractive therapeutic target for diabetes. PMID:26251404

Regulation of catalase expression in healthy and cancerous cells.

PubMed

Glorieux, Christophe; Zamocky, Marcel; Sandoval, Juan Marcelo; Verrax, Julien; Calderon, Pedro Buc

2015-10-01

Catalase is an important antioxidant enzyme that dismutates hydrogen peroxide into water and molecular oxygen. The catalase gene has all the characteristics of a housekeeping gene (no TATA box, no initiator element sequence, high GC content in promoter) and a core promoter that is highly conserved among species. We demonstrate in this review that within this core promoter, the presence of DNA binding sites for transcription factors, such as NF-Y and Sp1, plays an essential role in the positive regulation of catalase expression. Additional transcription factors, such as FoxO3a, are also involved in this regulatory process. There is strong evidence that the protein Akt/PKB in the PI3K signaling pathway plays a major role in the expression of catalase by modulating the activity of FoxO3a. Over the past decade, other transcription factors (PPARγ, Oct-1, etc.), as well as genetic, epigenetic, and posttranscriptional processes, have emerged as crucial contributors to the regulation of catalase expression. Altered expression levels of catalase have been reported in cancer tissues compared to their normal counterparts. Deciphering the molecular mechanisms that regulate catalase expression could, therefore, be of crucial importance for the future development of pro-oxidant cancer chemotherapy. Copyright © 2015. Published by Elsevier Inc.

Polymorphism of prion protein gene in Arctic fox (Vulpes lagopus).

PubMed

Wan, Jiayu; Bai, Xue; Liu, Wensen; Xu, Jing; Xu, Ming; Gao, Hongwei

2009-07-01

Prion diseases are fatal neurodegenerative disorders of humans and certain other mammals. Prion protein gene (Prnp) is associated with susceptibility and species barrier to prion diseases. No natural and experimental prion diseases have been documented to date in Arctic fox. In the present study, coding region of Prnp from 135 Arctic foxes were cloned and screened for polymorphisms. Our results indicated that the Arctic fox Prnp open reading frame (ORF) contains 771 nucleotides encoding 257 amino acids. Four single nucleotide polymorphisms (SNPs) (G312C, A337G, C541T, and A723G) were identified. SNPs G312C and A723G produced silent mutations, but SNPs A337G and C541T resulted in a M-V change at codon 113 and R-C at codon 181, respectively. The Arctic fox Prnp amino acid sequence was similar to that of the dog (XM 542906). In short, this study provides preliminary information about genotypes of Prnp in Arctic fox.

Compartmentalization of immune responses in human tuberculosis: few CD8+ effector T cells but elevated levels of FoxP3+ regulatory t cells in the granulomatous lesions.

PubMed

Rahman, Sayma; Gudetta, Berhanu; Fink, Joshua; Granath, Anna; Ashenafi, Senait; Aseffa, Abraham; Derbew, Milliard; Svensson, Mattias; Andersson, Jan; Brighenti, Susanna Grundström

2009-06-01

Immune responses were assessed at the single-cell level in lymph nodes from children with tuberculous lymphadenitis. Tuberculosis infection was associated with tissue remodeling of lymph nodes as well as altered cellular composition. Granulomas were significantly enriched with CD68+ macrophages expressing the M. tuberculosis complex-specific protein antigen MPT64 and inducible nitric oxide synthase. There was a significant increase in CD8+ cytolytic T cells surrounding the granuloma; however, CD8+ T cells expressed low levels of the cytolytic and antimicrobial effector molecules perforin and granulysin in the granulomatous lesions. Quantitative real-time mRNA analysis revealed that interferon-gamma, tumor necrosis factor-alpha, and interleukin-17 were not up-regulated in infected lymph nodes, but there was a significant induction of both transforming growth factor-beta and interleukin-13. In addition, granulomas contained an increased number of CD4+FoxP3+ T cells co-expressing the immunoregulatory cytotoxic T-lymphocyte antigen-4 and glucocorticoid-induced tumor necrosis factor receptor molecules. Low numbers of CD8+ T cells in the lesions correlated with high levels of transforming growth factor-beta and FoxP3+ regulatory T cells, suggesting active immunosuppression at the local infection site. Compartmentalization and skewing of the immune response toward a regulatory phenotype may result in an uncoordinated effector T-cell response that reduces granule-mediated killing of M. tuberculosis-infected cells and subsequent disease control.

A virus vector based on Canine Herpesvirus for vaccine applications in canids.

PubMed

Strive, T; Hardy, C M; Wright, J; Reubel, G H

2007-01-31

Canine Herpesvirus (CHV) is being developed as a virus vector for the vaccination of European red foxes. However, initial studies using recombinant CHV vaccines in foxes revealed viral attenuation and lack of antibody response to inserted foreign antigens. These findings were attributed both to inactivation of the thymidine kinase (TK) gene and excess foreign genetic material in the recombinant viral genome. In this study, we report an improved CHV-bacterial artificial chromosome (BAC) vector system designed to overcome attenuation in foxes. A non-essential region was identified in the CHV genome as an alternative insertion site for foreign genes. Replacement of a guanine/cytosine (GC)-rich intergenic region between UL21 and UL22 of CHV with a marker gene did not change growth behaviour in vitro, showing that this region is not essential for virus growth in cell culture. We subsequently produced a CHV-BAC vector with an intact TK gene in which the bacterial genes and the antigen expression cassette were inserted into this GC-rich locus. Unlike earlier constructs, the new CHV-BAC allowed self-excision of the bacterial genes via homologous recombination after transfection of BACs into cell culture. The BAC-CHV system was used to produce a recombinant virus that constitutively expressed porcine zona pellucida subunit C protein between the UL21 and UL22 genes of CHV. Complete self-excision of the bacterial genes from CHV was achieved within one round of replication whilst retaining antigen gene expression.

FoxO1 regulates apoptosis induced by asbestos in the MT-2 human T-cell line.

PubMed

Matsuzaki, Hidenori; Lee, Suni; Maeda, Megumi; Kumagai-Takei, Naoko; Nishimura, Yasumitsu; Otsuki, Takemi

2016-09-01

Asbestos is known to cause malignant mesothelioma and lung cancer. Recent studies implicate tumor immunity in the development of various tumors, including malignant mesothelioma. In order to establish an in vitro T-cell model to clarify the effects of long-term exposure of asbestos on tumor immunity, in this study, human T-cell line MT-2 cells were cultured with asbestos for longer than 8 months and the resultant cells (MT-2Rst) were assessed for the expression of forkhead transcription factor FoxO1. Gene expression analysis revealed that the amount of FoxO1 mRNA decreased after long-term exposure of the MT-2 cells to asbestos. In accordance with this reduction in FoxO1, pro-apoptotic Foxo1 target genes Puma, Fas ligand and Bim were also seen to be down-regulated in MT-2Rst cells. Furthermore, shRNA-mediated knock-down of FoxO1 reduced the number of apoptotic parental MT-2 cells after treatment with asbestos. On the other hand, over-expression of FoxO1 did not affect asbestos-induced apoptosis in MT-2Rst cells. These results suggested that FoxO1 played an important role in regulating asbestos-induced apoptosis and confirmed the presence of multiple pathways regulating resistance to asbestos in MT-2Rst cells.

Physiological adaptations to fasting in an actively wintering canid, the Arctic blue fox (Alopex lagopus).

PubMed

Mustonen, Anne-Mari; Pyykönen, Teija; Puukka, Matti; Asikainen, Juha; Hänninen, Sari; Mononen, Jaakko; Nieminen, Petteri

2006-01-01

This study investigated the physiological adaptations to fasting using the farmed blue fox (Alopex lagopus) as a model for the endangered wild arctic fox. Sixteen blue foxes were fed throughout the winter and 32 blue foxes were fasted for 22 d in Nov-Dec 2002. Half of the fasted blue foxes were food-deprived again for 22 d in Jan-Feb 2003. The farmed blue fox lost weight at a slower rate (0.97-1.02% body mass d(-1)) than observed previously in the arctic fox, possibly due to its higher initial body fat content. The animals experienced occasional fasting-induced hypoglycaemia, but their locomotor activity was not affected. The plasma triacylglycerol and glycerol concentrations were elevated during phase II of fasting indicating stimulated lipolysis, probably induced by the high growth hormone concentrations. The total cholesterol, HDL- and LDL-cholesterol, urea, uric acid and total protein levels and the urea:creatinine ratio decreased during fasting. Although the plasma levels of some essential amino acids increased, the blue foxes did not enter phase III of starvation characterized by stimulated proteolysis during either of the 22-d fasting procedures. Instead of excessive protein catabolism, it is liver dysfunction, indicated by the increased plasma bilirubin levels and alkaline phosphatase, alanine aminotransferase and aspartate aminotransferase activities, that may limit the duration of fasting in the species.

A Novel FOXE1 Mutation (R73S) in Bamforth–Lazarus Syndrome Causing Increased Thyroidal Gene Expression

PubMed Central

Carré, Aurore; Hamza, Rasha T.; Kariyawasam, Dulanjalee; Guillot, Loïc; Teissier, Raphaël; Tron, Elodie; Castanet, Mireille; Dupuy, Corinne; El Kholy, Mohamed; Polak, Michel

2014-01-01

Background: Homozygous loss-of-function mutations in the FOXE1 gene have been reported in several patients with partial or complete Bamforth–Lazarus syndrome: congenital hypothyroidism (CH) with thyroid dysgenesis (usually athyreosis), cleft palate, spiky hair, with or without choanal atresia, and bifid epiglottis. Here, our objective was to evaluate potential functional consequences of a FOXE1 mutation in a patient with a similar clinical phenotype. Methods: FOXE1 was sequenced in eight patients with thyroid dysgenesis and cleft palate. Transient transfection was performed in HEK293 cells using the thyroglobulin (TG) and thyroid peroxidase (TPO) promoters in luciferase reporter plasmids to assess the functional impact of the FOXE1 mutations. Primary human thyrocytes transfected with wild type and mutant FOXE1 served to assess the impact of the mutation on endogenous TG and TPO expression. Results: We identified and characterized the function of a new homozygous FOXE1 missense mutation (p.R73S) in a boy with a typical phenotype (athyreosis, cleft palate, and partial choanal atresia). This new mutation located within the forkhead domain was inherited from the heterozygous healthy consanguineous parents. In vitro functional studies in HEK293 cells showed that this mutant gene enhanced the activity of the TG and TPO gene promoters (1.5-fold and 1.7-fold respectively vs. wild type FOXE1; p<0.05), unlike the five mutations previously reported in Bamforth–Lazarus syndrome. The gain-of-function effect of the FOXE1-p.R73S mutant gene was confirmed by an increase in endogenous TG production in primary human thyrocytes. Conclusion: We identified a new homozygous FOXE1 mutation responsible for enhanced expression of the TG and TPO genes in a boy whose phenotype is similar to that reported previously in patients with loss-of-function FOXE1 mutations. This finding further delineates the role for FOXE1 in both thyroid and palate development, and shows that enhanced gene activity should be considered among the mechanisms underlying Bamforth–Lazarus syndrome. PMID:24219130

Hepatitis C virus induces a prediabetic state by directly impairing hepatic glucose metabolism in mice.

PubMed

Lerat, Hervé; Imache, Mohamed Rabah; Polyte, Jacqueline; Gaudin, Aurore; Mercey, Marion; Donati, Flora; Baudesson, Camille; Higgs, Martin R; Picard, Alexandre; Magnan, Christophe; Foufelle, Fabienne; Pawlotsky, Jean-Michel

2017-08-04

Virus-related type 2 diabetes is commonly observed in individuals infected with the hepatitis C virus (HCV); however, the underlying molecular mechanisms remain unknown. Our aim was to unravel these mechanisms using FL-N/35 transgenic mice expressing the full HCV ORF. We observed that these mice displayed glucose intolerance and insulin resistance. We also found that Glut-2 membrane expression was reduced in FL-N/35 mice and that hepatocyte glucose uptake was perturbed, partly accounting for the HCV-induced glucose intolerance in these mice. Early steps of the hepatic insulin signaling pathway, from IRS2 to PDK1 phosphorylation, were constitutively impaired in FL-N/35 primary hepatocytes via deregulation of TNFα/SOCS3. Higher hepatic glucose production was observed in the HCV mice, despite higher fasting insulinemia, concomitant with decreased expression of hepatic gluconeogenic genes. Akt kinase activity was higher in HCV mice than in WT mice, but Akt-dependent phosphorylation of the forkhead transcription factor FoxO1 at serine 256, which triggers its nuclear exclusion, was lower in HCV mouse livers. These findings indicate an uncoupling of the canonical Akt/FoxO1 pathway in HCV protein-expressing hepatocytes. Thus, the expression of HCV proteins in the liver is sufficient to induce insulin resistance by impairing insulin signaling and glucose uptake. In conclusion, we observed a complete set of events leading to a prediabetic state in HCV-transgenic mice, providing a valuable mechanistic explanation for HCV-induced diabetes in humans. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Inhibition of sirtuins 1 and 2 impairs cell survival and migration and modulates the expression of P-glycoprotein and MRP3 in hepatocellular carcinoma cell lines.

PubMed

Ceballos, María Paula; Decándido, Giulia; Quiroga, Ariel Darío; Comanzo, Carla Gabriela; Livore, Verónica Inés; Lorenzetti, Florencia; Lambertucci, Flavia; Chazarreta-Cifre, Lorena; Banchio, Claudia; Alvarez, María de Luján; Mottino, Aldo Domingo; Carrillo, María Cristina

2018-06-01

Sirtuins (SIRTs) 1 and 2 deacetylases are overexpressed in hepatocellular carcinoma (HCC) and are associated with tumoral progression and multidrug resistance (MDR). In this study we analyzed whether SIRTs 1 and 2 activities blockage was able to affect cellular survival and migration and to modulate p53 and FoxO1 acetylation in HepG2 and Huh7 cells. Moreover, we analyzed ABC transporters P-glycoprotein (P-gp) and multidrug resistance-associated protein 3 (MRP3) expression. We used cambinol and EX-527 as SIRTs inhibitors. Both drugs reduced cellular viability, number of colonies and cellular migration and augmented apoptosis. In 3D cultures, SIRTs inhibitors diminished spheroid growth and viability. 3D culture was less sensitive to drugs than 2D culture. The levels of acetylated p53 and FoxO1 increased after treatments. Drugs induced a decrease in ABC transporters mRNA and protein levels in HepG2 cells; however, only EX-527 was able to reduce MRP3 mRNA and protein levels in Huh7 cells. This is the first work demonstrating the regulation of MRP3 by SIRTs. In conclusion, both drugs decreased HCC cells survival and migration, suggesting SIRTs 1 and 2 activities blockage could be beneficial during HCC therapy. Downregulation of the expression of P-gp and MRP3 supports the potential application of SIRTs 1 and 2 inhibitions in combination with conventional chemotherapy. Copyright © 2018 Elsevier B.V. All rights reserved.

Transcriptional control, but not subcellular location, of PGC-1α is altered following exercise in a hot environment

PubMed Central

Shute, Robert J.; Kreiling, Jodi L.

2016-01-01

The purpose of this study was to determine mitochondrial biogenesis-related mRNA expression, binding of transcription factors to the peroxisome proliferator-activated receptor-γ coactivator 1-α (PGC-1α) promoter, and subcellular location of PGC-1α protein in human skeletal muscle following exercise in a hot environment compared with a room temperature environment. Recreationally trained males (n = 11) completed two trials in a temperature- and humidity-controlled environmental chamber. Each trial consisted of cycling in either a hot (H) or room temperature (C) environment (33 and 20°C, respectively) for 1 h at 60% of maximum wattage (Wmax) followed by 3 h of supine recovery at room temperature. Muscle biopsies were taken from the vastus lateralis pre-, post-, and 3 h postexercise. PGC-1α mRNA increased post (P = 0.039)- and 3 h postexercise in C (P = 0.002). PGC-1α, estrogen-related receptor-α (ERRα), and nuclear respiratory factor 1 (NRF-1) mRNA was all lower in H than C post (P = 0.038, P < 0.001, and P = 0.030, respectively)- and 3 h postexercise (P = 0.035, P = 0.007, and P < 0.001, respectively). Binding of cAMP response element-binding protein (CREB) (P = 0.005), myocyte enhancer factor 2 (MEF2) (P = 0.047), and FoxO forkhead box class-O1 (FoxO1) (P = 0.010) to the promoter region of the PGC-1α gene was lower in H than C. Nuclear PGC-1α protein increased postexercise in both H and C (P = 0.029) but was not different between trials (P = 0.602). These data indicate that acute exercise in a hot environment blunts expression of mitochondrial biogenesis-related mRNA, due to decreased binding of CREB, MEF2, and FoxO1 to the PGC-1α promoter. PMID:27445305

β-Hydroxy-β-methylbutyrate (HMB) normalizes dexamethasone-induced autophagy-lysosomal pathway in skeletal muscle.

PubMed

Girón, María D; Vílchez, Jose D; Shreeram, Sathyavageeswaran; Salto, Rafael; Manzano, Manuel; Cabrera, Elena; Campos, Nefertiti; Edens, Neile K; Rueda, Ricardo; López-Pedrosa, Jose M

2015-01-01

Dexamethasone-induced muscle atrophy is due to an increase in protein breakdown and a decrease in protein synthesis, associated with an over-stimulation of the autophagy-lysosomal pathway. These effects are mediated by alterations in IGF-1 and PI3K/Akt signaling. In this study, we have investigated the effects of β-Hydroxy-β-methylbutyrate (HMB) on the regulation of autophagy and proteosomal systems. Rats were treated during 21 days with dexamethasone as a model of muscle atrophy. Co-administration of HMB attenuated the effects promoted by dexamethasone. HMB ameliorated the loss in body weight, lean mass and the reduction of the muscle fiber cross-sectional area (shrinkage) in gastrocnemius muscle. Consequently, HMB produced an improvement in muscle strength in the dexamethasone-treated rats. To elucidate the molecular mechanisms responsible for these effects, rat L6 myotubes were used. In these cells, HMB significantly attenuated lysosomal proteolysis induced by dexamethasone by normalizing the changes observed in autophagosome formation, LC3 II, p62 and Bnip3 expression after dexamethasone treatment. HMB effects were mediated by an increase in FoxO3a phosphorylation and concomitant decrease in FoxO transcriptional activity. The HMB effect was due to the restoration of Akt signaling diminished by dexamethasone treatment. Moreover, HMB was also involved in the regulation of the activity of ubiquitin and expression of MurF1 and Atrogin-1, components of the proteasome system that are activated or up-regulated by dexamethasone. In conclusion, in vivo and in vitro studies suggest that HMB exerts protective effects against dexamethasone-induced muscle atrophy by normalizing the Akt/FoxO axis that controls autophagy and ubiquitin proteolysis.

β-Hydroxy-β-Methylbutyrate (HMB) Normalizes Dexamethasone-Induced Autophagy-Lysosomal Pathway in Skeletal Muscle

PubMed Central

Girón, María D.; Vílchez, Jose D.; Shreeram, Sathyavageeswaran; Salto, Rafael; Manzano, Manuel; Cabrera, Elena; Campos, Nefertiti; Edens, Neile K.; Rueda, Ricardo; López-Pedrosa, Jose M.

2015-01-01

Dexamethasone-induced muscle atrophy is due to an increase in protein breakdown and a decrease in protein synthesis, associated with an over-stimulation of the autophagy-lysosomal pathway. These effects are mediated by alterations in IGF-1 and PI3K/Akt signaling. In this study, we have investigated the effects of β-Hydroxy-β-methylbutyrate (HMB) on the regulation of autophagy and proteosomal systems. Rats were treated during 21 days with dexamethasone as a model of muscle atrophy. Co-administration of HMB attenuated the effects promoted by dexamethasone. HMB ameliorated the loss in body weight, lean mass and the reduction of the muscle fiber cross-sectional area (shrinkage) in gastrocnemius muscle. Consequently, HMB produced an improvement in muscle strength in the dexamethasone-treated rats. To elucidate the molecular mechanisms responsible for these effects, rat L6 myotubes were used. In these cells, HMB significantly attenuated lysosomal proteolysis induced by dexamethasone by normalizing the changes observed in autophagosome formation, LC3 II, p62 and Bnip3 expression after dexamethasone treatment. HMB effects were mediated by an increase in FoxO3a phosphorylation and concomitant decrease in FoxO transcriptional activity. The HMB effect was due to the restoration of Akt signaling diminished by dexamethasone treatment. Moreover, HMB was also involved in the regulation of the activity of ubiquitin and expression of MurF1 and Atrogin-1, components of the proteasome system that are activated or up-regulated by dexamethasone. In conclusion, in vivo and in vitro studies suggest that HMB exerts protective effects against dexamethasone-induced muscle atrophy by normalizing the Akt/FoxO axis that controls autophagy and ubiquitin proteolysis. PMID:25658432

Adenosine monophosphate activated protein kinase (AMPK), a mediator of estradiol-induced apoptosis in long-term estrogen deprived breast cancer cells.

PubMed

Chen, Haiyan; Wang, Ji-Ping; Santen, Richard J; Yue, Wei

2015-06-01

Estrogens stimulate growth of hormone-dependent breast cancer but paradoxically induce tumor regress under certain circumstances. We have shown that long-term estrogen deprivation (LTED) enhances the sensitivity of hormone dependent breast cancer cells to estradiol (E2) so that physiological concentrations of estradiol induce apoptosis in these cells. E2-induced apoptosis involve both intrinsic and extrinsic pathways but precise mechanisms remain unclear. We found that exposure of LTED MCF-7 cells to E2 activated AMP activated protein kinase (AMPK). In contrast, E2 inhibited AMPK activation in wild type MCF-7 cells where E2 prevents apoptosis. As a result of AMPK activation, the transcriptional activity of FoxO3, a downstream factor of AMPK, was up-regulated in E2 treatment of LTED. Increased activity of FoxO3 was demonstrated by up-regulation of three FoxO3 target genes, Bim, Fas ligand (FasL), and Gadd45α. Among them, Bim and FasL mediate intrinsic and extrinsic apoptosis respectively and Gadd45α causes cell cycle arrest at the G2/M phase. To further confirm the role of AMPK in apoptosis, we used AMPK activator AICAR in wild type MCF-7 cells and examined apoptosis, proliferation and expression of Bim, FasL, and Gadd45α. The effects of AICAR on these parameters recapitulated those observed in E2-treated LTED cells. Activation of AMPK by AICAR also increased expression of Bax in MCF-7 cells and its localization to mitochondria, which is a required process for apoptosis. These results reveal that AMPK is an important factor mediating E2-induced apoptosis in LTED cells, which is implicative of therapeutic potential for relapsing breast cancer after hormone therapy.

Fox (forkhead) genes are involved in the dorso-ventral patterning of the Xenopus mesoderm.

PubMed

El-Hodiri, H; Bhatia-Dey, N; Kenyon, K; Ault, K; Dirksen, M; Jamrich, M

2001-01-01

Fox (forkhead/winged helix) genes encode a family of transcription factors that are involved in embryonic pattern formation, regulation of tissue specific gene expression and tumorigenesis. Several of them are transcribed during Xenopus embryogenesis and are important for the patterning of ectoderm, mesoderm and endoderm. We have isolated three forkhead genes that are activated during gastrulation and play an important role in the dorso-ventral patterning of the mesoderm. XFKH1 (FoxA4b), the first vertebrate forkhead gene to be implicated in embryonic pattern formation, is expressed in the Spemann-Mangold organizer region and later in the embryonic notochord. XFKH7, the Xenopus orthologue of the murine Mfh1(Foxc2), is expressed in the presomitic mesoderm, but not in the notochord or lateral plate mesoderm. Finally, XFD-13'(FoxF1b)1 is expressed in the lateral plate mesoderm, but not in the notochord or presomitic mesoderm. Expression pattern and functional experiments indicate that these three forkhead genes are involved in the dorso-ventral patterning of the mesoderm.

Sodium Meta-Arsenite Ameliorates Hyperglycemia in Obese Diabetic db/db Mice by Inhibition of Hepatic Gluconeogenesis

PubMed Central

Lee, Eun-Kyu; Oh, Hyun-Hee; Choi, Cheol Soo; Kim, Sujong; Jun, Hee-Sook

2014-01-01

Sodium meta-arsenite (SA) is implicated in the regulation of hepatic gluconeogenesis-related genes in vitro; however, the effects in vivo have not been studied. We investigated whether SA has antidiabetic effects in a type 2 diabetic mouse model. Diabetic db/db mice were orally intubated with SA (10 mg kg−1 body weight/day) for 8 weeks. We examined hemoglobin A1c (HbA1c), blood glucose levels, food intake, and body weight. We performed glucose, insulin, and pyruvate tolerance tests and analyzed glucose production and the expression of gluconeogenesis-related genes in hepatocytes. We analyzed energy metabolism using a comprehensive animal metabolic monitoring system. SA-treated diabetic db/db mice had reduced concentrations of HbA1c and blood glucose levels. Exogenous glucose was quickly cleared in glucose tolerance tests. The mRNA expressions of genes for gluconeogenesis-related enzymes, glucose 6-phosphatase (G6Pase), and phosphoenolpyruvate carboxykinase (PEPCK) were significantly reduced in the liver of SA-treated diabetic db/db mice. In primary hepatocytes, SA treatment decreased glucose production and the expression of G6Pase, PEPCK, and hepatocyte nuclear factor 4 alpha (HNF-4α) mRNA. Small heterodimer partner (SHP) mRNA expression was increased in hepatocytes dependent upon the SA concentration. The expression of Sirt1 mRNA and protein was reduced, and acetylated forkhead box protein O1 (FoxO1) was induced by SA treatment in hepatocytes. In addition, SA-treated diabetic db/db mice showed reduced energy expenditure. Oral intubation of SA ameliorates hyperglycemia in db/db mice by reducing hepatic gluconeogenesis through the decrease of Sirt1 expression and increase in acetylated FoxO1. PMID:25610880

Myelin basic protein priming reduces the expression of Foxp3 in T cells via nitric oxide.

PubMed

Brahmachari, Saurav; Pahan, Kalipada

2010-02-15

Regulatory T cells (Tregs) play a vital role in autoimmune disorders. Among several markers, forkhead box p3 (Foxp3) is the most specific with regard to Treg activity. Therefore, understanding mechanisms that regulate Foxp3 expression is a critical step for unraveling the complicacy of autoimmune pathophysiology. The present study was undertaken to investigate the crosstalk between NO and Tregs. Interestingly, after myelin basic protein (MBP) priming, the expression of Foxp3 decreased in MBP-primed T cells. However, blocking NO either by inhibiting inducible NO synthase with l-N(6)-(1-iminoethyl)-lysine hydrochloride or through scavenging with PTIO or by pharmacological drugs, such as pravastatin, sodium benzoate, or gemfibrozil, restored the expression of Foxp3 in MBP-primed T cells. However, this restoration of Foxp3 by pharmacological drugs was reversed by S-nitrosoglutathione, an NO donor. Similarly, NO also decreased the populations of Tregs characterized by CD4(+)CD25(+) and CD25(+)FoxP3(+) phenotypes. We have further confirmed this inverse relationship between NO and Foxp3 by analyzing the mRNA expression of Foxp3 and characterizing CD25(+)FoxP3(+) or CD4(+)Foxp3(+) phenotypes from inducible NO synthase knockout mice. Moreover, this inverse relation between NO and Foxp3 also was observed during priming with myelin oligodendrocyte glycoprotein, another target neuroantigen in multiple sclerosis, as well as collagen, a target autoantigen in rheumatoid arthritis. Finally, we demonstrate that NO inhibited the expression of Foxp3 in MBP-primed T cells via soluble guanylyl cyclase-mediated production of cGMP. Taken together, our data imply a novel role of NO in suppressing Foxp3(+) Tregs via the soluble guanylyl cyclase pathway.

Structural study of the Fox-1 RRM protein hydration reveals a role for key water molecules in RRM-RNA recognition

PubMed Central

Blatter, Markus; Cléry, Antoine; Damberger, Fred F.

2017-01-01

Abstract The Fox-1 RNA recognition motif (RRM) domain is an important member of the RRM protein family. We report a 1.8 Å X-ray structure of the free Fox-1 containing six distinct monomers. We use this and the nuclear magnetic resonance (NMR) structure of the Fox-1 protein/RNA complex for molecular dynamics (MD) analyses of the structured hydration. The individual monomers of the X-ray structure show diverse hydration patterns, however, MD excellently reproduces the most occupied hydration sites. Simulations of the protein/RNA complex show hydration consistent with the isolated protein complemented by hydration sites specific to the protein/RNA interface. MD predicts intricate hydration sites with water-binding times extending up to hundreds of nanoseconds. We characterize two of them using NMR spectroscopy, RNA binding with switchSENSE and free-energy calculations of mutant proteins. Both hydration sites are experimentally confirmed and their abolishment reduces the binding free-energy. A quantitative agreement between theory and experiment is achieved for the S155A substitution but not for the S122A mutant. The S155 hydration site is evolutionarily conserved within the RRM domains. In conclusion, MD is an effective tool for predicting and interpreting the hydration patterns of protein/RNA complexes. Hydration is not easily detectable in NMR experiments but can affect stability of protein/RNA complexes. PMID:28505313

Forkhead-box series expression network is associated with outcome of clear-cell renal cell carcinoma.

PubMed

Jia, Zhongwei; Wan, Fangning; Zhu, Yao; Shi, Guohai; Zhang, Hailiang; Dai, Bo; Ye, Dingwei

2018-06-01

Previous studies have demonstrated that several members of the Forkhead-box (FOX) family of genes are associated with tumor progression and metastasis. The objective of the current study was to screen candidate FOX family genes identified from analysis of molecular networks in clear cell renal cell carcinoma (ccRCC). The expression of FOX family genes as well as FOX family-associated genes was examined, and Kaplan-Meier survival analysis was performed in The Cancer Genome Atlas (TCGA) cohort (n=525). Patient characteristics, including sex, age, tumor diameter, laterality, tumor-node-metastasis, tumor grade, stage, white blood cell count, platelet count, the levels of hemoglobin, overall survival (OS) and disease-free survival (DFS), were collected for univariate and multivariate Cox proportional hazards ratio analyses. A total of seven candidate FOX family genes were selected from the TCGA database subsequent to univariate and multivariate Cox proportional hazards ratio analyses. FOXA1, FOXA2, FOXD1, FOXD4L2, FOXK2 and FOXL1 were associated with poor OS time, while FOXA1, FOXA2, FOXD1 and FOXK2 were associated with poor DFS time (P<0.05). FOXN2 was associated with favorable outcomes for overall and disease-free survival (P<0.05). In the gene cluster network analysis, the expression of FOX family-associated genes, including nuclear receptor coactivator ( NCOA ) 1 , NADH-ubiquinone oxidoreductase flavoprotein 3 ( NDUFV3 ), phosphatidylserine decarboxylase ( PISD ) and pyruvate kinase liver and red blood cell ( PKLR ), were independent prognostic factors for OS in patients with ccRCC. Results of the present study revealed that the expression of FOX family genes, including FOXA1, FOXA2, FOXD1, FOXD4L2, FOXK2 and FOXL1 , and FOX family-associated genes, including NCOA1, NDUFV3, PISD and PKLR , are independent prognostic factors for patients with ccRCC.

FoxO1 transcriptional activities in VEGF expression and beyond: a key regulator in functional angiogenesis?

PubMed

Ren, Bin

2018-04-24

FoxO1 has emerged as an important regulator of angiogenesis. Recent work published in this Journal shows that FoxO1 regulates VEGF expression in keratinocytes and is required for angiogenesis in wound healing. Since FoxO1 also regulates CD36 transcription, and endothelial cell differentiation and vascular maturation, this transcription factor may be essential for the formation of functional vascular networks via coupling the regulation of CD36 in vascular endothelial cells under physiological and pathological conditions. Although many outstanding questions remain to be answered, the mechanisms by which FoxO1 regulates VEGF in keratinocytes provide insight into the development of functional angiogenesis and further our understanding of vascular biology. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Role of Forkhead Box Class O proteins in cancer progression and metastasis.

PubMed

Kim, Chang Geun; Lee, Hyemin; Gupta, Nehal; Ramachandran, Sharavan; Kaushik, Itishree; Srivastava, Sangeeta; Kim, Sung-Hoon; Srivastava, Sanjay K

2018-06-01

It is now widely accepted that several gene alterations including transcription factors are critically involved in cancer progression and metastasis. Forkhead Box Class O proteins (FoxOs) including FoxO1/FKHR, FoxO3/FKHRL1, FoxO4/AFX and FoxO6 transcription factors are known to play key roles in proliferation, apoptosis, metastasis, cell metabolism, aging and cancer biology through their phosphorylation, ubiquitination, acetylation and methylation. Though FoxOs are proved to be mainly regulated by upstream phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3 K)/Akt signaling pathway, the role of FoxOs in cancer progression and metastasis still remains unclear so far. Thus, with previous experimental evidences, the present review discussed the role of FoxOs in association with metastasis related molecules including cannabinoid receptor 1 (CNR1), Cdc25A/Cdk2, Src, serum and glucocorticoid inducible kinases (SGKs), CXCR4, E-cadherin, annexin A8 (ANXA8), Zinc finger E-box-binding homeobox 2 (ZEB2), human epidermal growth factor receptor 2 (HER2) and mRNAs such as miR-182, miR-135b, miR-499-5p, miR-1274a, miR-150, miR-34b/c and miR-622, subsequently analyzed the molecular mechanism of some natural compounds targeting FoxOs and finally suggested future research directions in cancer progression and metastasis. Copyright © 2017 Elsevier Ltd. All rights reserved.

Regulatory T cell levels and cytokine production in active non-infectious uveitis: in-vitro effects of pharmacological treatment.

PubMed

Molins, B; Mesquida, M; Lee, R W J; Llorenç, V; Pelegrín, L; Adán, A

2015-03-01

The aim of this study was to quantify the proportion of regulatory T cells (Treg ) and cytokine expression by peripheral blood mononuclear cells (PBMCs) in patients with active non-infectious uveitis, and to evaluate the effect of in-vitro treatment with infliximab, dexamethasone and cyclosporin A on Treg levels and cytokine production in PBMCs from uveitis patients and healthy subjects. We included a group of 21 patients with active non-infectious uveitis and 18 age-matched healthy subjects. The proportion of forkhead box protein 3 (FoxP3)(+) Treg cells and intracellular tumour necrosis factor (TNF)-α expression in CD4(+) T cells was determined by flow cytometry. PBMCs were also either rested or activated with anti-CD3/anti-CD28 and cultured in the presence or absence of dexamethasone, cyclosporin A and infliximab. Supernatants of cultured PBMCs were collected and TNF-α, interleukin (IL)-10, IL-17 and interferon (IFN)-γ levels were measured by enzyme-linked immunosorbent assay (ELISA). No significant differences were observed in nTreg levels between uveitis patients and healthy subjects. However, PBMCs from uveitis patients produced significantly higher amounts of TNF-α and lower amounts of IL-10. Dexamethasone treatment in vitro significantly reduced FoxP3(+) Treg levels in PBMCs from both healthy subjects and uveitis patients, and all tested drugs significantly reduced TNF-α production in PBMCs. Dexamethasone and cyclosporin A significantly reduced IL-17 and IFN-γ production in PBMCs and dexamethasone up-regulated IL-10 production in activated PBMCs from healthy subjects. Our results suggest that PBMCs from patients with uveitis express more TNF-α and less IL-10 than healthy subjects, and this is independent of FoxP3(+) Treg levels. Treatment with infliximab, dexamethasone and cyclosporin A in vitro modulates cytokine production, but does not increase the proportion of FoxP3(+) Treg cells. © 2014 British Society for Immunology.

Regulatory T cell levels and cytokine production in active non-infectious uveitis: in-vitro effects of pharmacological treatment

PubMed Central

Molins, B; Mesquida, M; Lee, R W J; Llorenç, V; Pelegrín, L; Adán, A

2015-01-01

The aim of this study was to quantify the proportion of regulatory T cells (Treg) and cytokine expression by peripheral blood mononuclear cells (PBMCs) in patients with active non-infectious uveitis, and to evaluate the effect of in-vitro treatment with infliximab, dexamethasone and cyclosporin A on Treg levels and cytokine production in PBMCs from uveitis patients and healthy subjects. We included a group of 21 patients with active non-infectious uveitis and 18 age-matched healthy subjects. The proportion of forkhead box protein 3 (FoxP3)+ Treg cells and intracellular tumour necrosis factor (TNF)-α expression in CD4+ T cells was determined by flow cytometry. PBMCs were also either rested or activated with anti-CD3/anti-CD28 and cultured in the presence or absence of dexamethasone, cyclosporin A and infliximab. Supernatants of cultured PBMCs were collected and TNF-α, interleukin (IL)-10, IL-17 and interferon (IFN)-γ levels were measured by enzyme-linked immunosorbent assay (ELISA). No significant differences were observed in nTreg levels between uveitis patients and healthy subjects. However, PBMCs from uveitis patients produced significantly higher amounts of TNF-α and lower amounts of IL-10. Dexamethasone treatment in vitro significantly reduced FoxP3+ Treg levels in PBMCs from both healthy subjects and uveitis patients, and all tested drugs significantly reduced TNF-α production in PBMCs. Dexamethasone and cyclosporin A significantly reduced IL-17 and IFN-γ production in PBMCs and dexamethasone up-regulated IL-10 production in activated PBMCs from healthy subjects. Our results suggest that PBMCs from patients with uveitis express more TNF-α and less IL-10 than healthy subjects, and this is independent of FoxP3+ Treg levels. Treatment with infliximab, dexamethasone and cyclosporin A in vitro modulates cytokine production, but does not increase the proportion of FoxP3+ Treg cells. PMID:25354724

CrMAPK3 regulates the expression of iron-deficiency-responsive genes in Chlamydomonas reinhardtii.

PubMed

Fei, Xiaowen; Yu, Junmei; Li, Yajun; Deng, Xiaodong

2017-05-16

Under iron-deficient conditions, Chlamydomonas exhibits high affinity for iron absorption. Nevertheless, the response, transmission, and regulation of downstream gene expression in algae cells have not to be investigated. Considering that the MAPK pathway is essential for abiotic stress responses, we determined whether this pathway is involved in iron deficiency signal transduction in Chlamydomonas. Arabidopsis MAPK gene sequences were used as entry data to search for homologous genes in Chlamydomonas reinhardtii genome database to investigate the functions of mitogen-activated protein kinase (MAPK) gene family in C. reinhardtii under iron-free conditions. Results revealed 16 C. reinhardtii MAPK genes labeled CrMAPK2-CrMAPK17 with TXY conserved domains and low homology to MAPK in yeast, Arabidopsis, and humans. The expression levels of these genes were then analyzed through qRT-PCR and exposure to high salt (150 mM NaCl), low nitrogen, or iron-free conditions. The expression levels of these genes were also subjected to adverse stress conditions. The mRNA levels of CrMAPK2, CrMAPK3, CrMAPK4, CrMAPK5, CrMAPK6, CrMAPK8, CrMAPK9, and CrMAPK11 were remarkably upregulated under iron-deficient stress. The increase in CrMAPK3 expression was 43-fold greater than that in the control. An RNA interference vector was constructed and transformed into C. reinhardtii 2A38, an algal strain with an exogenous FOX1:ARS chimeric gene, to silence CrMAPK3. After this gene was silenced, the mRNA levels and ARS activities of FOX1:ARS chimeric gene and endogenous CrFOX1 were decreased. The mRNA levels of iron-responsive genes, such as CrNRAMP2, CrATX1, CrFTR1, and CrFEA1, were also remarkably reduced. CrMAPK3 regulates the expression of iron-deficiency-responsive genes in C. reinhardtii.

Epigenetic features of FoxP3 in children with cow's milk allergy.

PubMed

Paparo, Lorella; Nocerino, Rita; Cosenza, Linda; Aitoro, Rosita; D'Argenio, Valeria; Del Monaco, Valentina; Di Scala, Carmen; Amoroso, Antonio; Di Costanzo, Margherita; Salvatore, Francesco; Berni Canani, Roberto

2016-01-01

DNA methylation of the Th1 and Th2 cytokine genes is altered during cow's milk allergy (CMA). Forkhead box transcription factor 3 (FoxP3) is essential for the development and function of regulatory T cells (Tregs) and is involved in oral tolerance acquisition. We assessed whether tolerance acquisition in children with IgE-mediated CMA is associated with DNA demethylation of the Treg-specific demethylated region (TSDR) of FoxP3. Forty children (aged 3-18 months) were enrolled: 10 children with active IgE-mediated CMA (group 1), 10 children who outgrew CMA after dietary treatment with an extensively hydrolyzed casein formula containing the probiotic Lactobacillus rhamnosus GG (group 2), 10 children who outgrew CMA after treatment with other formulas (group 3), and 10 healthy controls (group 4). FoxP3 TSDR demethylation and expression were measured in mononuclear cells purified from peripheral blood of the four groups of children. FoxP3 TSDR demethylation was significantly lower in children with active IgE-mediated CMA than in either children who outgrew CMA or in healthy children. Formula selection influenced the FoxP3 TSDR demethylation profile. The FoxP3 TSDR demethylation rate and expression level were correlated. Tolerance acquisition in children with IgE-mediated CMA involves epigenetic regulation of the FoxP3 gene. This feature could be a new target for preventive and therapeutic strategies against CMA.

Phenotypically non-suppressive cells predominate among FoxP3-positive cells in oral lichen planus.

PubMed

Schreurs, Olav; Karatsaidis, Andreas; Schenck, Karl

2016-11-01

Oral lichen planus (OLP) is a common T-cell-dominated oral chronic inflammatory disease occurring in periods of remission, quiescence, activity with pronounced inflammation, and acute ulceration. Cell infiltrates in OLP contain varying numbers of CD4 + T cells expressing the transcription factor FoxP3. FoxP3 + CD4 + T cells are, however, a heterogeneous cell population containing suppressive and non-suppressive cells, and their distribution in infiltrates from OLP is unknown. Biopsies were taken from normal oral mucosa (n = 8) and OLP lesions (n = 19), and a set of in situ methods for the determination of the functional phenotype of FoxP3 + CD4 + T cells was applied. Numbers of FoxP3 + CD4 + T cells were highest in the atrophic form of the disease, yet low in the ulcerative form. The main FoxP3 + CD4 + T-cell population observed was FoxP3 + CD45RA - CD25 + CD45RO + and CD15s - , a phenotype delineating a non-suppressive subset. Numbers of cells with an actively suppressing phenotype (FoxP3 + CD45RA - CD25 + CD45RO + and CD15s + ) were, however, about twice as high in reticular lesions as compared with the atrophic form. Many FoxP3 + CD4 + T cells expressed T-bet, the hallmark transcription factor for IFN-γ-producing T cells, indicating that they may enhance immune and inflammatory responses rather than suppress them. The absence of actively suppressing FoxP3 + CD4 + T cells may in part explain why OLP is a remarkably persisting condition, in spite of the presence of substantially high numbers of FoxP3 + CD4 + T cells. The findings emphasize that it is crucial to examine not only numbers but also functional phenotype of FoxP3 + CD4 + T cells in human tissues. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Detection and significance of TregFoxP3+ and Th17 cells in peripheral blood of non-small cell lung cancer patients

PubMed Central

Li, Sha; Li, Yan; Qu, Xun; Liu, Xiaolin

2014-01-01

Introduction The aim of this study was to explore the relationships between TregFoxP3+ cells and Th17 cells and occurrence of lung cancer. Material and methods The proportions of TregFoxP3+ and Th17 cells, the expression of FoxP3 and RORγt mRNA, and the levels of related cell factors such as transforming growth factor-β (TGF-β), interleukin IL-17 (IL-17) and IL-23 were determined respectively by flow cytometry analysis, real-time-polymerase chain reaction (PCR), and ELISA in peripheral blood of 18 healthy people and 26 patients with non-small cell lung cancer (NSCLC). Results The levels of TregFoxP3+ and Th17, expression of FoxP3 and RORγt mRNA, and ratios of TregFoxP3+/Th17 and FoxP3/RORγt in peripheral blood with NSCLC were higher than those in healthy controls (p < 0.05). The proportion of Th17 cells from NSCLC patients was positively correlated with that of TregFoxP3+ (r = 0.81, p < 0.05). The receiver-operating characteristic (ROC) curve demonstrates that the increased level of TregFoxP3+/Th17 in the peripheral blood may be a useful indicator in early diagnosis of non-small cell lung carcinoma. The TregFoxP3+/Th17 and FoxP3/RORγt levels for patients in stage IV were higher than those of patients in stages I, II, and III (p < 0.05). The levels of TGF-β, IL-17, and IL-23 were higher in NSCLC patients than those in healthy controls. Conclusions The results suggest that ratios of Treg/Th17 correlate with the stage of NSCLC. PMID:24904654

Striatal FoxP2 Is Actively Regulated during Songbird Sensorimotor Learning

PubMed Central

Teramitsu, Ikuko; Poopatanapong, Amy; Torrisi, Salvatore; White, Stephanie A.

2010-01-01

Background Mutations in the FOXP2 transcription factor lead to language disorders with developmental onset. Accompanying structural abnormalities in cortico-striatal circuitry indicate that at least a portion of the behavioral phenotype is due to organizational deficits. We previously found parallel FoxP2 expression patterns in human and songbird cortico/pallio-striatal circuits important for learned vocalizations, suggesting that FoxP2's function in birdsong may generalize to speech. Methodology/Principal Findings We used zebra finches to address the question of whether FoxP2 is additionally important in the post-organizational function of these circuits. In both humans and songbirds, vocal learning depends on auditory guidance to achieve and maintain optimal vocal output. We tested whether deafening prior to or during the sensorimotor phase of song learning disrupted FoxP2 expression in song circuitry. As expected, the songs of deafened juveniles were abnormal, however basal FoxP2 levels were unaffected. In contrast, when hearing or deaf juveniles sang for two hours in the morning, FoxP2 was acutely down-regulated in the striatal song nucleus, area X. The extent of down-regulation was similar between hearing and deaf birds. Interestingly, levels of FoxP2 and singing were correlated only in hearing birds. Conclusions/Significance Hearing appears to link FoxP2 levels to the amount of vocal practice. As juvenile birds spent more time practicing than did adults, their FoxP2 levels are likely to be low more often. Behaviorally-driven reductions in the mRNA encoding this transcription factor could ultimately affect downstream molecules that function in vocal exploration, especially during sensorimotor learning. PMID:20062527

Dehydroepiandrosterone replacement in patients with Addison's disease has a bimodal effect on regulatory (CD4+CD25hi and CD4+FoxP3+) T cells.

PubMed

Coles, Alasdair J; Thompson, Sara; Cox, Amanda L; Curran, Suzanne; Gurnell, Elli M; Chatterjee, V Krishna

2005-12-01

Oral replacement of the near-total deficiency of dehydroepiandrosterone (DHEA) in patients with Addison's disease (adrenal insufficiency) enhances mood and well-being and reduces fatigue. We studied the immunological effects of 12 wk of oral DHEA treatment in ten patients with Addison's disease receiving their normal mineralo- and glucocorticoid hormone replacement. We found that baseline circulating regulatory T cells were reduced in Addison's disease patients compared to controls, a hitherto unrecognised defect in this disorder. Oral DHEA treatment had a bimodal effect on naturally occurring regulatory (CD4+CD25hiFoxP3+) T cells and lymphocyte FoxP3 expression. Oral DHEA replacement restored normal levels of regulatory T cells and led to increased FoxP3 expression. These effects were probably responsible for a suppression of constitutive cytokine expression following DHEA withdrawal. In contrast, oral DHEA treatment led to reduced FoxP3 expression induced by TCR engagement and so augmented the cytokine response, but without a bias towards the Th1 or Th2 phenotype. NK and NKT cell numbers fell during DHEA treatment, and homeostatic lymphocyte proliferation was increased. We conclude that DHEA replacement in Addison's disease has significant immunomodulatory properties and propose that it has a greater impact on the human immune system than would be expected from its classification as a dietary supplement.

Structural and functional characterisation of FOXO/Acan-DAF-16 from the parasitic nematode Angiostrongylus cantonensis.

PubMed

Yan, Baolong; Sun, Weiwei; Yan, Lanzhu; Zhang, Liangliang; Zheng, Yuan; Zeng, Yuzhen; Huang, Huicong; Liang, Shaohui

2016-12-01

Fork head box transcription factors subfamily O (FoxO) is regarded to be significant in cell-cycle control, cell differentiation, ageing, stress response, apoptosis, tumour formation and DNA damage repair. In the free-living nematode Caenorhabditis elegans, the FoxO transcription factor is encoded by Ce-daf-16, which is negatively regulated by insulin-like signaling (IIS) and involved in promoting dauer formation through bringing about its hundreds of downstream genes expression. In nematode parasites, orthologues of daf-16 from several species have been identified, with functions in rescue of dauer phenotypes determined in a surrogate system C. elegans. In this study, we identified the FoxO encoding gene, Acan-daf-16, from the parasitic nematode Angiostrongylus cantonensis, and determined the genomic structures, transcripts and functions far more thorough in longevity, stress resistance and dauer formation. Acan-daf-16 encodes two proteins, Acan-DAF-16A and Acan-DAF-16B, consisting of 555 and 491 amino acids, respectively. Both isoforms possess the highly conserved fork head domains. Acan-daf-16A and Acan-daf-16B are expressed from distinct promoters. The expression patterns of Acan-daf-16 isoforms in the C. elegans surrogate system showed that p Acan-daf-16a:gfp was expressed in all cells of C. elegans, including the pharynx, and the expression of p Acan-daf-16b:gfp was restricted to the pharynx. In addition to the same genomic organization to the orthologue in C. elegans, Ce-daf-16, both Acan-DAF-16 isoforms could restore the C. elegans daf-16(mg54) mutation in longevity, dauer formation and stress resistance, in spite of the partial complementation of Acan-DAF-16B isoform in longevity. These findings provide further evidence of the functional conservation of DAF-16s between parasitic nematodes and the free-living nematode C. elegans. Copyright © 2016. Published by Elsevier B.V.

An essential role of a FoxD gene in notochord induction in Ciona embryos.

PubMed

Imai, Kaoru S; Satoh, Nori; Satou, Yutaka

2002-07-01

A key issue for understanding the early development of the chordate body plan is how the endoderm induces notochord formation. In the ascidian Ciona, nuclear accumulation of beta-catenin is the first step in the process of endoderm specification. We show that nuclear accumulation of beta-catenin directly activates the gene (Cs-FoxD) for a winged helix/forkhead transcription factor and that this gene is expressed transiently at the 16- and 32-cell stages in endodermal cells. The function of Cs-FoxD, however, is not associated with differentiation of the endoderm itself but is essential for notochord differentiation or induction. In addition, it is likely that the inductive signal that appears to act downstream of Cs-FoxD does not act over a long range. It has been suggested that FGF or Notch signal transduction pathway mediates ascidian notochord induction. Our previous study suggests that Cs-FGF4/6/9 is partially involved in the notochord induction. The present experimental results suggest that the expression and function of Cs-FGF4/6/9 and Cs-FoxD are not interdependent, and that the Notch pathway is involved in B-line notochord induction downstream of Cs-FoxD.

Probing the Mechanism of Inactivation of the FOX-4 Cephamycinase by Avibactam.

PubMed

Nukaga, Michiyoshi; Papp-Wallace, Krisztina M; Hoshino, Tyuji; Lefurgy, Scott T; Bethel, Christopher R; Barnes, Melissa D; Zeiser, Elise T; Johnson, J Kristie; Bonomo, Robert A

2018-05-01

Ceftazidime-avibactam is a "second-generation" β-lactam-β-lactamase inhibitor combination that is effective against Enterobacteriaceae expressing class A extended-spectrum β-lactamases, class A carbapenemases, and/or class C cephalosporinases. Knowledge of the interactions of avibactam, a diazabicyclooctane with different β-lactamases, is required to anticipate future resistance threats. FOX family β-lactamases possess unique hydrolytic properties with a broadened substrate profile to include cephamycins, partly as a result of an isoleucine at position 346, instead of the conserved asparagine found in most AmpCs. Interestingly, a single amino acid substitution at N346 in the Citrobacter AmpC is implicated in resistance to the aztreonam-avibactam combination. In order to understand how diverse active-site topologies affect avibactam inhibition, we tested a panel of clinical Enterobacteriaceae isolates producing bla FOX using ceftazidime-avibactam, determined the biochemical parameters for inhibition using the FOX-4 variant, and probed the atomic structure of avibactam with FOX-4. Avibactam restored susceptibility to ceftazidime for most isolates producing bla FOX ; two isolates, one expressing bla FOX-4 and the other producing bla FOX-5 , displayed an MIC of 16 μg/ml for the combination. FOX-4 possessed a k 2 / K value of 1,800 ± 100 M -1 · s -1 and an off rate ( k off ) of 0.0013 ± 0.0003 s -1 Mass spectrometry showed that the FOX-4-avibactam complex did not undergo chemical modification for 24 h. Analysis of the crystal structure of FOX-4 with avibactam at a 1.5-Å resolution revealed a unique characteristic of this AmpC β-lactamase. Unlike in the Pseudomonas -derived cephalosporinase 1 (PDC-1)-avibactam crystal structure, interactions (e.g., hydrogen bonding) between avibactam and position I346 in FOX-4 are not evident. Furthermore, another residue is not observed to be close enough to compensate for the loss of these critical hydrogen-bonding interactions. This observation supports findings from the inhibition analysis of FOX-4; FOX-4 possessed the highest K d (dissociation constant) value (1,600 nM) for avibactam compared to other AmpCs (7 to 660 nM). Medicinal chemists must consider the properties of extended-spectrum AmpCs, such as the FOX β-lactamases, for the design of future diazabicyclooctanes. Copyright © 2018 American Society for Microbiology.

Selenium deficiency-induced thioredoxin suppression and thioredoxin knock down disbalanced insulin responsiveness in chicken cardiomyocytes through PI3K/Akt pathway inhibition.

PubMed

Yang, Jie; Hamid, Sattar; Cai, Jingzeng; Liu, Qi; Xu, Shiwen; Zhang, Ziwei

2017-10-01

Thioredoxin (Txn) system is the most crucial antioxidant defense mechanism in cell consisting of Txn, thioredoxin reductase (TR) and Nicotinamide Adenine Dinucleotide Phosphate (NADPH). Perturbations in Txn system may compromise cell survival through oxidative stress induction. Metabolic activity of insulin plays important roles in fulfilling the stable and persistent demands of heart through glucose metabolism. However, the roles of Txn and Txn system in insulin modulated cardiac energy metabolism have been less reported. Therefore, to investigate the role of Txn in myocardial metabolism, we developed a Se-deficient chicken model (0.033mg/kg) for in-vivo and Txn knock down cardiomyocytes culture model (siRNA) for in-vitro studies. Quantitative real time PCR and western blotting was performed. Se deficiency suppressed Txn and TR in cardiac tissues. Significant increases in ROS (P<0.05) levels signify the onset of oxidative stress and in both models. Se deficiency-induced Txn suppression model and Txn knock down cardiomyocytes models significantly decreased (P<0.05), the mRNA and protein levels of insulin-like growth factors (IGF1, IGF2), IGF-binding proteins (IGFBP2, IGFBP4), insulin receptor (IR), insulin receptor substrates (IRS1, IRS2), and glucose transporters (GLUT1, GLUT3, GLUT8), however, IGFBP3 expression increased in Txn knock down cardiomyocytes. In addition, in contrast to their respective controls, Se deficiency-induced Txn depleted tissues and Txn deleted cardiomyocytes showed suppression in mRNA and protein levels of PI3K, AKT, P-PI3K, and repression in FOX, P-FOX JNK genes. Combing the in vitro and in vivo experiments, we demonstrate that Txn gene suppression can cause dysfunction of insulin-modulated cardiac energy metabolism and increase insulin resistance through PI3K-Akt pathway inhibition. Herein, we conclude that inactivation of Txn system can alter cellular insulin response through IRS/PI3K/Akt pathway repression and JNK and FOX expression. These findings point out that Txn system can redox regulate the insulin dependent glucose metabolism in heart and is essential for cell vitality. Moreover, the increased expression of IGFBP3 indicates that it can be a potential negative modulator of metabolic activity of insulin in Txn deficient cells. Copyright © 2017 Elsevier Inc. All rights reserved.

A single nucleotide polymorphism associated with isolated cleft lip and palate, thyroid cancer and hypothyroidism alters the activity of an oral epithelium and thyroid enhancer near FOXE1

PubMed Central

Lidral, Andrew C.; Liu, Huan; Bullard, Steven A.; Bonde, Greg; Machida, Junichiro; Visel, Axel; Uribe, Lina M. Moreno; Li, Xiao; Amendt, Brad; Cornell, Robert A.

2015-01-01

Three common diseases, isolated cleft lip and cleft palate (CLP), hypothyroidism and thyroid cancer all map to the FOXE1 locus, but causative variants have yet to be identified. In patients with CLP, the frequency of coding mutations in FOXE1 fails to account for the risk attributable to this locus, suggesting that the common risk alleles reside in nearby regulatory elements. Using a combination of zebrafish and mouse transgenesis, we screened 15 conserved non-coding sequences for enhancer activity, identifying three that regulate expression in a tissue specific pattern consistent with endogenous foxe1 expression. These three, located −82.4, −67.7 and +22.6 kb from the FOXE1 start codon, are all active in the oral epithelium or branchial arches. The −67.7 and +22.6 kb elements are also active in the developing heart, and the −67.7 kb element uniquely directs expression in the developing thyroid. Within the −67.7 kb element is the SNP rs7850258 that is associated with all three diseases. Quantitative reporter assays in oral epithelial and thyroid cell lines show that the rs7850258 allele (G) associated with CLP and hypothyroidism has significantly greater enhancer activity than the allele associated with thyroid cancer (A). Moreover, consistent with predicted transcription factor binding differences, the −67.7 kb element containing rs7850258 allele G is significantly more responsive to both MYC and ARNT than allele A. By demonstrating that this common non-coding variant alters FOXE1 expression, we have identified at least in part the functional basis for the genetic risk of these seemingly disparate disorders. PMID:25652407

Unexpected role for dosage compensation in the control of dauer arrest, insulin-like signaling, and FoxO transcription factor activity in Caenorhabditis elegans.

PubMed

Dumas, Kathleen J; Delaney, Colin E; Flibotte, Stephane; Moerman, Donald G; Csankovszki, Gyorgyi; Hu, Patrick J

2013-07-01

During embryogenesis, an essential process known as dosage compensation is initiated to equalize gene expression from sex chromosomes. Although much is known about how dosage compensation is established, the consequences of modulating the stability of dosage compensation postembryonically are not known. Here we define a role for the Caenorhabditis elegans dosage compensation complex (DCC) in the regulation of DAF-2 insulin-like signaling. In a screen for dauer regulatory genes that control the activity of the FoxO transcription factor DAF-16, we isolated three mutant alleles of dpy-21, which encodes a conserved DCC component. Knockdown of multiple DCC components in hermaphrodite and male animals indicates that the dauer suppression phenotype of dpy-21 mutants is due to a defect in dosage compensation per se. In dpy-21 mutants, expression of several X-linked genes that promote dauer bypass is elevated, including four genes encoding components of the DAF-2 insulin-like pathway that antagonize DAF-16/FoxO activity. Accordingly, dpy-21 mutation reduced the expression of DAF-16/FoxO target genes by promoting the exclusion of DAF-16/FoxO from nuclei. Thus, dosage compensation enhances dauer arrest by repressing X-linked genes that promote reproductive development through the inhibition of DAF-16/FoxO nuclear translocation. This work is the first to establish a specific postembryonic function for dosage compensation in any organism. The influence of dosage compensation on dauer arrest, a larval developmental fate governed by the integration of multiple environmental inputs and signaling outputs, suggests that the dosage compensation machinery may respond to external cues by modulating signaling pathways through chromosome-wide regulation of gene expression.

FoxA and LIPG endothelial lipase control the uptake of extracellular lipids for breast cancer growth

PubMed Central

Slebe, Felipe; Rojo, Federico; Vinaixa, Maria; García-Rocha, Mar; Testoni, Giorgia; Guiu, Marc; Planet, Evarist; Samino, Sara; Arenas, Enrique J.; Beltran, Antoni; Rovira, Ana; Lluch, Ana; Salvatella, Xavier; Yanes, Oscar; Albanell, Joan; Guinovart, Joan J.; Gomis, Roger R.

2016-01-01

The mechanisms that allow breast cancer (BCa) cells to metabolically sustain rapid growth are poorly understood. Here we report that BCa cells are dependent on a mechanism to supply precursors for intracellular lipid production derived from extracellular sources and that the endothelial lipase (LIPG) fulfils this function. LIPG expression allows the import of lipid precursors, thereby contributing to BCa proliferation. LIPG stands out as an essential component of the lipid metabolic adaptations that BCa cells, and not normal tissue, must undergo to support high proliferation rates. LIPG is ubiquitously and highly expressed under the control of FoxA1 or FoxA2 in all BCa subtypes. The downregulation of either LIPG or FoxA in transformed cells results in decreased proliferation and impaired synthesis of intracellular lipids. PMID:27045898

Integrative analysis identifies targetable CREB1/FoxA1 transcriptional co-regulation as a predictor of prostate cancer recurrence.

PubMed

Sunkel, Benjamin; Wu, Dayong; Chen, Zhong; Wang, Chiou-Miin; Liu, Xiangtao; Ye, Zhenqing; Horning, Aaron M; Liu, Joseph; Mahalingam, Devalingam; Lopez-Nicora, Horacio; Lin, Chun-Lin; Goodfellow, Paul J; Clinton, Steven K; Jin, Victor X; Chen, Chun-Liang; Huang, Tim H-M; Wang, Qianben

2016-05-19

Identifying prostate cancer-driving transcription factors (TFs) in addition to the androgen receptor promises to improve our ability to effectively diagnose and treat this disease. We employed an integrative genomics analysis of master TFs CREB1 and FoxA1 in androgen-dependent prostate cancer (ADPC) and castration-resistant prostate cancer (CRPC) cell lines, primary prostate cancer tissues and circulating tumor cells (CTCs) to investigate their role in defining prostate cancer gene expression profiles. Combining genome-wide binding site and gene expression profiles we define CREB1 as a critical driver of pro-survival, cell cycle and metabolic transcription programs. We show that CREB1 and FoxA1 co-localize and mutually influence each other's binding to define disease-driving transcription profiles associated with advanced prostate cancer. Gene expression analysis in human prostate cancer samples found that CREB1/FoxA1 target gene panels predict prostate cancer recurrence. Finally, we showed that this signaling pathway is sensitive to compounds that inhibit the transcription co-regulatory factor MED1. These findings not only reveal a novel, global transcriptional co-regulatory function of CREB1 and FoxA1, but also suggest CREB1/FoxA1 signaling is a targetable driver of prostate cancer progression and serves as a biomarker of poor clinical outcomes. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

Protein Kinase D1 Signaling in Angiogenic Gene Expression and VEGF-Mediated Angiogenesis.

PubMed

Ren, Bin

2016-01-01

Protein kinase D 1 (PKD-1) is a signaling kinase important in fundamental cell functions including migration, proliferation, and differentiation. PKD-1 is also a key regulator of gene expression and angiogenesis that is essential for cardiovascular development and tumor progression. Further understanding molecular aspects of PKD-1 signaling in the regulation of angiogenesis may have translational implications in obesity, cardiovascular disease, and cancer. The author will summarize and provide the insights into molecular mechanisms by which PKD-1 regulates transcriptional expression of angiogenic genes, focusing on the transcriptional regulation of CD36 by PKD-1-FoxO1 signaling axis along with the potential implications of this axis in arterial differentiation and morphogenesis. He will also discuss a new concept of dynamic balance between proangiogenic and antiangiogenic signaling in determining angiogenic switch, and stress how PKD-1 signaling regulates VEGF signaling-mediated angiogenesis.

Protein Kinase D1 Signaling in Angiogenic Gene Expression and VEGF-Mediated Angiogenesis

PubMed Central

Ren, Bin

2016-01-01

Protein kinase D 1 (PKD-1) is a signaling kinase important in fundamental cell functions including migration, proliferation, and differentiation. PKD-1 is also a key regulator of gene expression and angiogenesis that is essential for cardiovascular development and tumor progression. Further understanding molecular aspects of PKD-1 signaling in the regulation of angiogenesis may have translational implications in obesity, cardiovascular disease, and cancer. The author will summarize and provide the insights into molecular mechanisms by which PKD-1 regulates transcriptional expression of angiogenic genes, focusing on the transcriptional regulation of CD36 by PKD-1-FoxO1 signaling axis along with the potential implications of this axis in arterial differentiation and morphogenesis. He will also discuss a new concept of dynamic balance between proangiogenic and antiangiogenic signaling in determining angiogenic switch, and stress how PKD-1 signaling regulates VEGF signaling-mediated angiogenesis. PMID:27200349

Hypothalamic KLF4 mediates leptin's effects on food intake via AgRP

PubMed Central

Imbernon, Monica; Sanchez-Rebordelo, Estrella; Gallego, Rosalia; Gandara, Marina; Lear, Pamela; Lopez, Miguel; Dieguez, Carlos; Nogueiras, Ruben

2014-01-01

Krüppel-like factor 4 (KLF4) is a zinc-finger-type transcription factor expressed in a range of tissues that plays multiple functions. We report that hypothalamic KLF4 represents a new transcription factor specifically modulating agouti-related protein (AgRP) expression in vivo. Hypothalamic KLF4 colocalizes with AgRP neurons and is modulated by nutritional status and leptin. Over-expression of KLF4 in the hypothalamic arcuate nucleus (ARC) induces food intake and increases body weight through the specific stimulation of AgRP, as well as blunting leptin sensitivity in lean rats independent of forkhead box protein 01 (FoxO1). Down-regulation of KLF4 in the ARC inhibits fasting-induced food intake in both lean and diet-induced obese (DIO) rats. Silencing KLF4, however, does not, on its own, enhance peripheral leptin sensitivity in DIO rats. PMID:24944903

Hypothalamic KLF4 mediates leptin's effects on food intake via AgRP.

PubMed

Imbernon, Monica; Sanchez-Rebordelo, Estrella; Gallego, Rosalia; Gandara, Marina; Lear, Pamela; Lopez, Miguel; Dieguez, Carlos; Nogueiras, Ruben

2014-07-01

Krüppel-like factor 4 (KLF4) is a zinc-finger-type transcription factor expressed in a range of tissues that plays multiple functions. We report that hypothalamic KLF4 represents a new transcription factor specifically modulating agouti-related protein (AgRP) expression in vivo. Hypothalamic KLF4 colocalizes with AgRP neurons and is modulated by nutritional status and leptin. Over-expression of KLF4 in the hypothalamic arcuate nucleus (ARC) induces food intake and increases body weight through the specific stimulation of AgRP, as well as blunting leptin sensitivity in lean rats independent of forkhead box protein 01 (FoxO1). Down-regulation of KLF4 in the ARC inhibits fasting-induced food intake in both lean and diet-induced obese (DIO) rats. Silencing KLF4, however, does not, on its own, enhance peripheral leptin sensitivity in DIO rats.

FoxP3+CD4+CD25+ T cells with regulatory properties can be cultured from colonic mucosa of patients with Crohn's disease

PubMed Central

Kelsen, J; Agnholt, J; Hoffmann, H J; Rømer, J L; Hvas, C L; Dahlerup, J F

2005-01-01

CD4+CD25+ regulatory T cells (Tregs) are involved in the maintenance of peripheral tolerance and ensure a balanced immune response competent of fighting pathogens and at the same time recognizing commensals as harmless. This feature is lost in Crohn's disease (CD). The forkhead/winged helix transcription factor FoxP3 is a master gene for Treg function and defects in the FoxP3 gene lead to a clinical picture similar to inflammatory bowel disease (IBD). Murine colitis can be cured by adoptive transfer of Tregs and ex vivo-generated gut-specific Tregs represent an attractive option for therapy in CD. Thus, defective Tregs could contribute to the development of CD. We cultured biopsies of colonic mucosa in the presence of high concentrations of interleukin (IL)-2 and IL-4 to overcome the anergic nature of naturally occurring CD4+CD25+ Tregs in the mucosa. We investigated the expression of FoxP3 and regulatory potential of gut-derived CD4+CD25+ T cells cultured from patients with CD and healthy individuals. The FoxP3 expression was analysed by reverse transcriptase polymerase chain reaction (RT-PCR), and the suppressive effect of FoxP3+CD4+CD25+ T cells on proliferation and cytokine production of autologous CD4+ T cells was assessed by flow cytometry. Cultured gut-derived T cells with CD4+CD25+ phenotype expressed FoxP3 and were able as the freshly isolated Tregs from peripheral blood to suppress proliferation and cytokine production of autologous CD4+ T cells. Thus, we demonstrate that FoxP3+CD4+CD25+ T cells with regulatory properties can be propagated in vitro from inflamed mucosa of CD patients, which may be of interest in adoptive immunotherapy. PMID:16045746

Insulin-like Growth Factor 1 Rescues R28 Retinal Neurons from Apoptotic Death through ERK-mediated BimEL Phosphorylation Independent of Akt

PubMed Central

Kong, Dejuan; Gong, Lijie; Arnold, Edith; Shanmugam, Sumathi; Fort, Patrice E.; Gardner, Thomas W.; Abcouwer, Steven F.

2016-01-01

Insulin-like growth factor 1 (IGF-1) can provide long-term neurotrophic support by activation of Akt, inhibition of FoxO nuclear localization and suppression of Bim gene transcription in multiple neuronal systems. However, MEK/ERK activation can also promote neuron survival through phosphorylation of BimEL. We explored the contribution of the PI3K/Akt/FoxO and MEK/ERK/BimEL pathways in IGF-1 stimulated survival after serum deprivation (SD) of R28 cells differentiated to model retinal neurons. IGF-1 caused rapid activation of Akt leading to FoxO1/3-T32/T24 phosphorylation, and prevented FoxO1/3 nuclear translocation and Bim mRNA upregulation in response to SD. IGF-1 also caused MAPK/MEK pathway activation as indicated by ERK1/2-T202/Y204 and Bim-S65 phosphorylation. Overexpression of FoxO1 increased Bim mRNA expression and amplified the apoptotic response to SD without shifting the serum response curve. Inhibition of Akt activation with LY294002 or by Rictor knockdown did not block the protective effect of IGF-1, while inhibition of MEK activity with PD98059 prevented Bim phosphorylation and blocked IGF-1 protection. In addition, knockdown of Bim expression was protective during SD, while co-silencing of FoxO1 and Fox03 expression had little effect. Thus, the PI3K/Akt/FoxO pathway was not essential for protection from SD-induced apoptosis by IGF-1 in R28 cells. Instead, IGF-1 protection was dependent on activation of the MEK/ERK pathway leading to BimEL phosphorylation, which is known to prevent Bax/Bak oligomerization and activation of the intrinsic mitochondrial apoptosis pathway. These studies demonstrate the requirement of the MEK/ERK pathway in a model of retinal neuron cell survival and highlight the cell specificity for IGF-1 signaling in this response. PMID:27511131

Autophagy induction by leptin contributes to suppression of apoptosis in cancer cells and xenograft model: Involvement of p53/FoxO3A axis

PubMed Central

Nepal, Saroj; Kim, Mi Jin; Hong, Jin Tae; Kim, Sang Hyun; Sohn, Dong-Hwan; Lee, Sung Hee; Song, Kyung; Choi, Dong Young; Lee, Eung Seok; Park, Pil-Hoon

2015-01-01

Leptin, a hormone mainly produced from adipose tissue, has been shown to induce proliferation of cancer cells. However, the molecular mechanisms underlying leptin-induced tumor progression have not been clearly elucidated. In the present study, we investigated the role of autophagy in leptin-induced cancer cell proliferation using human hepatoma (HepG2) and breast cancer cells (MCF-7), and tumor growth in a xenograft model. Herein, we showed that leptin treatment caused autophagy induction as assessed by increase in expression of autophagy-related genes, including beclin-1, Atg5 and LC3 II, further induction of autophagosome formation and autophagic flux. Interestingly, inhibition of autophagic process by treatment with inhibitors and LC3B gene silencing blocked leptin-induced increase in cell number and suppression of apoptosis, indicating a crucial role of autophagy in leptin-induced tumor progression. Moreover, gene silencing of p53 or FoxO3A prevented leptin-induced LC3 II protein expression, suggesting an involvement of p53/FoxO3A axis in leptin-induced autophagy activation. Leptin administration also accelerated tumor growth in BALB/c nude mice, which was found to be autophagy dependent. Taken together, our results demonstrate that leptin-induced tumor growth is mediated by autophagy induction and autophagic process would be a promising target to regulate development of cancer caused by leptin production. PMID:25704884

Stromal Gene Expression and Function in Primary Breast Tumors that Metastasize to Bone Cancer

DTIC Science & Technology

2006-07-01

surrounding bone microenvironment were investigated by purifying endothelial cells from tumor-burdened and non-tumor burdened spines . 4T1...of Balb/c mice. Fresh resected tissue (normal fat pad, primary tumor tissue or the metastatic sites spine , femur and lung) was obtained and cell... Hedgehog signalling pathway: Lasp1, CREBBP/EP300 inhibitory protein 1 and FoxP1. Of interest as well are a number of differentially regulated ESTs

Proliferation of murine c-kit(pos) cardiac stem cells stimulated with IGF-1 is associated with Akt-1 mediated phosphorylation and nuclear export of FoxO3a and its effect on downstream cell cycle regulators.

PubMed

Johnson, Ann Mary; Kartha, C C

2014-04-01

Insulin-like growth factor-1 (IGF-1) is known to promote proliferation in many cell types including c-kit(pos) cardiac stem cells (CSCs). Downstream signaling pathways of IGF-1 induced CSC proliferation have not been investigated. An important downstream target of IGF-1/Akt-1 signaling is FoxO3a, a key negative regulator of cell-cycle progression. We studied the effect of IGF-1 on proliferation of c-kit(pos) murine CSCs and found that IGF-1-mediated cell proliferation is associated with FoxO3a phosphorylation and inactivation of its transcriptional activity. PI3 inhibitors LY294002 and Wortmannin abolished the effect of IGF-1 on FoxO3a phosphorylation indicating that FoxO3a phosphorylation is mediated by PI3/Akt-1 pathway. In cells with FoxO3a translocation to the cytoplasm, there is decreased expression of cell-cycle inhibitors such as p27(kip1) and p57(kip2) and increased expression of CyclinD1. Our study provides evidence that IGF-1 induced CSC proliferation could be the result of FoxO3a inactivation and its downstream effect on cell-cycle regulators.

Recombinant ESAT-6-CFP10 Fusion Protein Induction of Th1/Th2 Cytokines and FoxP3 Expressing Treg Cells in Pulmonary TB.

PubMed

Jackson-Sillah, Dolly; Cliff, Jacqueline M; Mensah, Gloria Ivy; Dickson, Emmanuel; Sowah, Sandra; Tetteh, John K A; Addo, Kwasi K; Ottenhoff, Tom H M; Bothamley, Graham; Dockrell, Hazel M

2013-01-01

Early secretory antigenic target 6 (ESAT-6) and culture filtrate protein 10 (CFP-10) are Mycobacterium tuberculosis (Mtb)-specific antigens that are secreted by actively metabolising bacteria and contribute to the virulence of the bacteria. Their ability to induce Treg and Th2 responses, particularly during the first two weeks of treatment, has not been comprehensively examined to date. The purpose of this work was to characterise Th1, Th2 and Treg responses to rESAT-6-CFP10 fusion protein in TB patients before and during the intensive phase of treatment and in healthy M.bovis BCG vaccinated donors. Forty-six newly diagnosed, HIV-negative, smear-positive pulmonary TB patients and 20 healthy donors were recruited in the UK and Ghana. Their peripheral blood mononuclear cells (PBMC) were used in ex vivo ELISPOT and in vitro cultures to identify immunological parameters of interest. The study confirmed that protective immune responses to rESAT-6-CFP10 are impaired in active TB but improved during treatment: circulating antigen-specific IL-4-producing T-cells were increased in untreated TB but declined by two weeks of treatment while the circulating antigen-specific IFN-γ producing T cells which showed a transient rise at one week of treatment, persisted at baseline levels at two months of treatment. In vitro T cell proliferation and IFN-γ production were reduced, while IL-4 and CD4(+)FoxP3(+)CD25(hi) cell expression were increased in response to rESAT-6-CFP10 fusion protein in untreated TB. These responses were reversed during early treatment of TB. These observations support further investigations into the possible utility of these parameters as markers of active disease and favourable treatment outcomes.

Investigation of FoxO3 dynamics during erythroblast development in β-thalassemia major.

PubMed

Thanuthanakhun, Naruchit; Nuntakarn, Lalana; Sampattavanich, Somponnat; Anurathapan, Usanarat; Phuphanitcharoenkun, Suphanun; Pornpaiboonstid, Savichaya; Borwornpinyo, Suparerk; Hongeng, Suradej

2017-01-01

The FoxO3 transcription factor is a key regulator of oxidative stress and erythroid maturation during erythropoiesis. In this study, we explored the involvement of FoxO3 in severe β-thalassemia. Using primary CD34+ hematopoietic progenitor cells from patients with β-thalassemia major, we successfully developed an in vitro model of ineffective erythropoiesis. Based on this model, FoxO3 activity was quantified in single cells using high throughput imaging flow cytometry. This study revealed a significant reduction of FoxO3 activity during the late stage of erythroblast differentiation in β-thalassemia, in contrast to erythropoiesis in normal cells that maintain persistent activation of FoxO3. In agreement with the decreased FoxO3 activity in β-thalassemia, the expression of FoxO3 target genes was also found to decrease, concurrent with elevated phosphorylation of AKT, most clearly at the late stage of erythroid differentiation. Our findings provide further evidence for the involvement of FoxO3 during terminal erythropoiesis and confirm the modulation of the PI3K/AKT pathway as a potential therapeutic strategy for β-thalassemia.

Tumor necrosis factor alpha blockade exacerbates murine psoriasis-like disease by enhancing Th17 function and decreasing expansion of Treg cells.

PubMed

Ma, Hak-Ling; Napierata, Lee; Stedman, Nancy; Benoit, Stephen; Collins, Mary; Nickerson-Nutter, Cheryl; Young, Deborah A

2010-02-01

Patients with psoriasis and psoriatic arthritis respond well to tumor necrosis factor alpha (TNFalpha) blockers in general; however, there is now mounting evidence that a small cohort of patients with rheumatoid arthritis who receive TNFalpha blockers develop psoriasis. This study was undertaken to explore the mechanisms underlying TNFalpha blockade-induced exacerbation of skin inflammation in murine psoriasis-like skin disease. Skin inflammation was induced in BALB/c scid/scid mice after they received CD4+CD45RB(high)CD25- (naive CD4) T cells from donor mice. These mice were treated with either anti-interleukin-12 (anti-IL-12)/23p40 antibody or murine TNFRII-Fc fusion protein and were examined for signs of disease, including histologic features, various cytokine levels in the serum, and cytokine or FoxP3 transcripts in the affected skin and draining lymph node (LN) cells. In a separate study, naive CD4+ T cells were differentiated into Th1 or Th17 lineages with anti-CD3/28 magnetic beads and appropriate cytokines in the presence or absence of TNFalpha. Cytokine gene expression from these differentiated cells was also determined. Neutralization of TNFalpha exacerbated skin inflammation and markedly enhanced the expression of the proinflammatory cytokines IL-1beta, IL-6, IL-17, IL-21, and IL-22 but suppressed FoxP3 expression in the skin and reduced the number of FoxP3-positive Treg cells in the draining LNs. TNFalpha also demonstrated a divergent role during priming and reactivation of naive T cells. These results reveal a novel immunoregulatory role of TNFalpha on Th17 and Treg cells in some individuals, which may account for the exacerbation of skin inflammation in some patients who receive anti-TNF treatments.

Dendrobium nobile Lindl. alkaloids regulate metabolism gene expression in livers of mice.

PubMed

Xu, Yun-Yan; Xu, Ya-Sha; Wang, Yuan; Wu, Qin; Lu, Yuan-Fu; Liu, Jie; Shi, Jing-Shan

2017-10-01

In our previous studies, Dendrobium nobile Lindl. alkaloids (DNLA) has been shown to have glucose-lowering and antihyperlipidaemia effects in diabetic rats, in rats fed with high-fat diets, and in mice challenged with adrenaline. This study aimed to examine the effects of DNLA on the expression of glucose and lipid metabolism genes in livers of mice. Mice were given DNLA at doses of 10-80 mg/kg, po for 8 days, and livers were removed for total RNA and protein isolation to perform real-time RT-PCR and Western blot analysis. Dendrobium nobile Lindl. alkaloids increased PGC1α at mRNA and protein levels and increased glucose metabolism gene Glut2 and FoxO1 expression. DNLA also increased the expression of fatty acid β-oxidation genes Acox1 and Cpt1a. The lipid synthesis regulator Srebp1 (sterol regulatory element-binding protein-1) was decreased, while the lipolysis gene ATGL was increased. Interestingly, DNLA increased the expression of antioxidant gene metallothionein-1 and NADPH quinone oxidoreductase-1 (Nqo1) in livers of mice. Western blot on selected proteins confirmed these changes including the increased expression of GLUT4 and PPARα. DNLA has beneficial effects on liver glucose and lipid metabolism gene expressions, and enhances the Nrf2-antioxidant pathway gene expressions, which could play integrated roles in regulating metabolic disorders. © 2017 Royal Pharmaceutical Society.

Interplay between metabolic rate and diet quality in the South American fox, Pseudalopex culpaeus.

PubMed

Silva, Sergio I; Jaksic, Fabian M; Bozinovic, Francisco

2004-01-01

We studied the metabolic costs associated with the ingestion of peppertree fruits (Schinus molle) in the culpeo fox, Pseudalopex culpaeus, the second largest canid in South America. Throughout its range of distribution, this fox feeds on rodents and other small vertebrates, and also on peppertree fruits, which represent 98% of total fruits consumed in semiarid Chile. Peppertree contains a high diversity of phytochemicals. Foxes feeding on diets containing rats and peppertree fruits (mixed diets) exhibited a 98.9% increase in basal rate of metabolism when compared to rat-acclimated foxes. Thus, acute ingestion of chemically defended fruits has an energetic cost for the fox, reflected in higher values of basal metabolism. Increased metabolic rates may be associated with increased protein synthesis for detoxification and for tissue repair, including the production of biotransformation enzymes.

Changes in fat oxidation in response to various regimes of high intensity interval training (HIIT).

PubMed

Astorino, Todd Anthony; Schubert, Matthew M

2018-01-01

Increased whole-body fat oxidation (FOx) has been consistently demonstrated in response to moderate intensity continuous exercise training. Completion of high intensity interval training (HIIT) and its more intense form, sprint interval training (SIT), has also been reported to increase FOx in different populations. An explanation for this increase in FOx is primarily peripheral adaptations via improvements in mitochondrial content and function. However, studies examining changes in FOx are less common in response to HIIT or SIT than those determining increases in maximal oxygen uptake which is concerning, considering that FOx has been identified as a predictor of weight gain and glycemic control. In this review, we explored physiological and methodological issues underpinning existing literature concerning changes in FOx in response to HIIT and SIT. Our results show that completion of interval training increases FOx in approximately 50% of studies, with the frequency of increased FOx higher in response to studies using HIIT compared to SIT. Significant increases in β-HAD, citrate synthase, fatty acid binding protein, or FAT/CD36 are likely responsible for the greater FOx seen in these studies. We encourage scientists to adopt strict methodological procedures to attenuate day-to-day variability in FOx, which is dramatic, and develop standardized procedures for assessing FOx, which may improve detection of changes in FOx in response to HIIT.

CNTNAP2 is a direct FoxP2 target in vitro and in vivo in zebra finches: complex regulation by age and activity.

PubMed

Adam, I; Mendoza, E; Kobalz, U; Wohlgemuth, S; Scharff, C

2017-07-01

Mutations of FOXP2 are associated with altered brain structure, including the striatal part of the basal ganglia, and cause a severe speech and language disorder. Songbirds serve as a tractable neurobiological model for speech and language research. Experimental downregulation of FoxP2 in zebra finch Area X, a nucleus of the striatal song control circuitry, affects synaptic transmission and spine densities. It also renders song learning and production inaccurate and imprecise, similar to the speech impairment of patients carrying FOXP2 mutations. Here we show that experimental downregulation of FoxP2 in Area X using lentiviral vectors leads to reduced expression of CNTNAP2, a FOXP2 target gene in humans. In addition, natural downregulation of FoxP2 by age or by singing also downregulated CNTNAP2 expression. Furthermore, we report that FoxP2 binds to and activates the avian CNTNAP2 promoter in vitro. Taken together these data establish CNTNAP2 as a direct FoxP2 target gene in songbirds, likely affecting synaptic function relevant for song learning and song maintenance. © 2017 The Authors. Genes, Brain and Behavior published by International Behavioural and Neural Genetics Society and John Wiley & Sons Ltd.

Downregulation of SIRT1 signaling underlies hepatic autophagy impairment in glycogen storage disease type Ia

PubMed Central

Cho, Jun-Ho; Pan, Chi-Jiunn; Anduaga, Javier

2017-01-01

A deficiency in glucose-6-phosphatase-α (G6Pase-α) in glycogen storage disease type Ia (GSD-Ia) leads to impaired glucose homeostasis and metabolic manifestations including hepatomegaly caused by increased glycogen and neutral fat accumulation. A recent report showed that G6Pase-α deficiency causes impairment in autophagy, a recycling process important for cellular metabolism. However, the molecular mechanism underlying defective autophagy is unclear. Here we show that in mice, liver-specific knockout of G6Pase-α (L-G6pc-/-) leads to downregulation of sirtuin 1 (SIRT1) signaling that activates autophagy via deacetylation of autophagy-related (ATG) proteins and forkhead box O (FoxO) family of transcriptional factors which transactivate autophagy genes. Consistently, defective autophagy in G6Pase-α-deficient liver is characterized by attenuated expressions of autophagy components, increased acetylation of ATG5 and ATG7, decreased conjugation of ATG5 and ATG12, and reduced autophagic flux. We further show that hepatic G6Pase-α deficiency results in activation of carbohydrate response element-binding protein, a lipogenic transcription factor, increased expression of peroxisome proliferator-activated receptor-γ (PPAR-γ), a lipid regulator, and suppressed expression of PPAR-α, a master regulator of fatty acid β-oxidation, all contributing to hepatic steatosis and downregulation of SIRT1 expression. An adenovirus vector-mediated increase in hepatic SIRT1 expression corrects autophagy defects but does not rectify metabolic abnormalities associated with G6Pase-α deficiency. Importantly, a recombinant adeno-associated virus (rAAV) vector-mediated restoration of hepatic G6Pase-α expression corrects metabolic abnormalities, restores SIRT1-FoxO signaling, and normalizes defective autophagy. Taken together, these data show that hepatic G6Pase-α deficiency-mediated down-regulation of SIRT1 signaling underlies defective hepatic autophagy in GSD-Ia. PMID:28558013

Elevated hepatic fatty acid elongase-5 activity corrects dietary fat-induced hyperglycemia in obese BL/6J mice[S

PubMed Central

Tripathy, Sasmita; Torres-Gonzalez, Moises; Jump, Donald B.

2010-01-01

Elevated hepatic fatty acid elongase-5 (Elovl5) activity lowers blood glucose in fasted chow-fed C57BL/6J mice. As high-fat diets induce hyperglycemia and suppress hepatic Elovl5 activity, we tested the hypothesis that elevated hepatic Elovl5 expression attenuates hyperglycemia in high-fat-diet-induced obese mice. Increasing hepatic Elovl5 activity by a recombinant adenoviral approach restored blood glucose and insulin, HOMA-IR, and glucose tolerance to normal values in obese mice. Elevated Elovl5 activity increased hepatic content of Elovl5 products (20:3,n-6, 22:4,n-6) and suppressed levels of enzymes (Pck1, G6Pc) and transcription factors (FoxO1 and PGC1α, but not CRTC2) involved in gluconeogenesis. Effects of Elovl5 on FoxO1 nuclear abundance correlated with increased phosphorylation of FoxO1, Akt, and the catalytic unit of PP2A, as well as a decline in cellular abundance of TRB3. Such changes are mechanistically linked to the regulation of FoxO1 nuclear abundance and gluconeogenesis. These results show that Elovl5 activity impacts the hepatic abundance and phosphorylation status of multiple proteins involved in gluconeogenesis. Our findings establish a link between fatty acid elongation and hepatic glucose metabolism and suggest a role for regulators of Elovl5 activity in the treatment of diet-induced hyperglycemia. PMID:20488798

The transcription factor FoxB mediates temporal loss of cellular competence for notochord induction in ascidian embryos.

PubMed

Hashimoto, Hidehiko; Enomoto, Takashi; Enomoto, Atsushi; Kumano, Gaku; Nishida, Hiroki

2011-06-01

In embryos of the ascidian Halocynthia roretzi, the competence of isolated presumptive notochord blastomeres to respond to fibroblast growth factor (FGF) for induction of the primary notochord decays by 1 hour after cleavage from the 32- to 64-cell stage. This study analyzes the molecular mechanisms responsible for this loss of competence and provides evidence for a novel mechanism. A forkhead family transcription factor, FoxB, plays a role in competence decay by preventing the induction of notochord-specific Brachyury (Bra) gene expression by the FGF/MAPK signaling pathway. Unlike the mechanisms reported previously in other animals, no component in the FGF signal transduction cascade appeared to be lost or inactivated at the time of competence loss. Knockdown of FoxB functions allowed the isolated cells to retain their competence for a longer period, and to respond to FGF with expression of Bra beyond the stage at which competence was normally lost. FoxB acts as a transcription repressor by directly binding to the cis-regulatory element of the Bra gene. Our results suggest that FoxB prevents ectopic induction of the notochord fate within the cells that assume a default nerve cord fate, after the stage when notochord induction has been completed. The merit of this system is that embryos can use the same FGF signaling cascade again for another purpose in the same cell lineage at later stages by keeping the signaling cascade itself available. Temporally and spatially regulated FoxB expression in nerve cord cells was promoted by the ZicN transcription factor and absence of FGF/MAPK signaling.

Forkhead Box O6 (FoxO6) Depletion Attenuates Hepatic Gluconeogenesis and Protects against Fat-induced Glucose Disorder in Mice.

PubMed

Calabuig-Navarro, Virtu; Yamauchi, Jun; Lee, Sojin; Zhang, Ting; Liu, Yun-Zi; Sadlek, Kelsey; Coudriet, Gina M; Piganelli, Jon D; Jiang, Chun-Lei; Miller, Rita; Lowe, Mark; Harashima, Hideyoshi; Dong, H Henry

2015-06-19

Excessive endogenous glucose production contributes to fasting hyperglycemia in diabetes. FoxO6 is a distinct member of the FoxO subfamily. To elucidate the role of FoxO6 in hepatic gluconeogenesis and assess its contribution to the pathogenesis of fasting hyperglycemia in diabetes, we generated FoxO6 knock-out (FoxO6-KO) mice followed by determining the effect of FoxO6 loss-of-function on hepatic gluconeogenesis under physiological and pathological conditions. FoxO6 depletion attenuated hepatic gluconeogenesis and lowered fasting glycemia in FoxO6-KO mice. FoxO6-deficient primary hepatocytes were associated with reduced capacities to produce glucose in response to glucagon. When fed a high fat diet, FoxO6-KO mice exhibited significantly enhanced glucose tolerance and reduced blood glucose levels accompanied by improved insulin sensitivity. These effects correlated with attenuated hepatic gluconeogenesis in FoxO6-KO mice. In contrast, wild-type littermates developed fat-induced glucose intolerance with a concomitant induction of fasting hyperinsulinemia and hyperglycemia. Furthermore, FoxO6-KO mice displayed significantly diminished macrophage infiltration into liver and adipose tissues, correlating with the reduction of macrophage expression of C-C chemokine receptor 2 (CCR2), a factor that is critical for regulating macrophage recruitment in peripheral tissues. Our data indicate that FoxO6 depletion protected against diet-induced glucose intolerance and insulin resistance by attenuating hepatic gluconeogenesis and curbing macrophage infiltration in liver and adipose tissues in mice. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

Forkhead Box O6 (FoxO6) Depletion Attenuates Hepatic Gluconeogenesis and Protects against Fat-induced Glucose Disorder in Mice*

PubMed Central

Calabuig-Navarro, Virtu; Yamauchi, Jun; Lee, Sojin; Zhang, Ting; Liu, Yun-Zi; Sadlek, Kelsey; Coudriet, Gina M.; Piganelli, Jon D.; Jiang, Chun-Lei; Miller, Rita; Lowe, Mark; Harashima, Hideyoshi; Dong, H. Henry

2015-01-01

Excessive endogenous glucose production contributes to fasting hyperglycemia in diabetes. FoxO6 is a distinct member of the FoxO subfamily. To elucidate the role of FoxO6 in hepatic gluconeogenesis and assess its contribution to the pathogenesis of fasting hyperglycemia in diabetes, we generated FoxO6 knock-out (FoxO6-KO) mice followed by determining the effect of FoxO6 loss-of-function on hepatic gluconeogenesis under physiological and pathological conditions. FoxO6 depletion attenuated hepatic gluconeogenesis and lowered fasting glycemia in FoxO6-KO mice. FoxO6-deficient primary hepatocytes were associated with reduced capacities to produce glucose in response to glucagon. When fed a high fat diet, FoxO6-KO mice exhibited significantly enhanced glucose tolerance and reduced blood glucose levels accompanied by improved insulin sensitivity. These effects correlated with attenuated hepatic gluconeogenesis in FoxO6-KO mice. In contrast, wild-type littermates developed fat-induced glucose intolerance with a concomitant induction of fasting hyperinsulinemia and hyperglycemia. Furthermore, FoxO6-KO mice displayed significantly diminished macrophage infiltration into liver and adipose tissues, correlating with the reduction of macrophage expression of C-C chemokine receptor 2 (CCR2), a factor that is critical for regulating macrophage recruitment in peripheral tissues. Our data indicate that FoxO6 depletion protected against diet-induced glucose intolerance and insulin resistance by attenuating hepatic gluconeogenesis and curbing macrophage infiltration in liver and adipose tissues in mice. PMID:25944898

Investigation of FoxO3 dynamics during erythroblast development in β-thalassemia major

PubMed Central

Thanuthanakhun, Naruchit; Nuntakarn, Lalana; Sampattavanich, Somponnat; Anurathapan, Usanarat; Phuphanitcharoenkun, Suphanun; Pornpaiboonstid, Savichaya; Hongeng, Suradej

2017-01-01

The FoxO3 transcription factor is a key regulator of oxidative stress and erythroid maturation during erythropoiesis. In this study, we explored the involvement of FoxO3 in severe β-thalassemia. Using primary CD34+ hematopoietic progenitor cells from patients with β-thalassemia major, we successfully developed an in vitro model of ineffective erythropoiesis. Based on this model, FoxO3 activity was quantified in single cells using high throughput imaging flow cytometry. This study revealed a significant reduction of FoxO3 activity during the late stage of erythroblast differentiation in β-thalassemia, in contrast to erythropoiesis in normal cells that maintain persistent activation of FoxO3. In agreement with the decreased FoxO3 activity in β-thalassemia, the expression of FoxO3 target genes was also found to decrease, concurrent with elevated phosphorylation of AKT, most clearly at the late stage of erythroid differentiation. Our findings provide further evidence for the involvement of FoxO3 during terminal erythropoiesis and confirm the modulation of the PI3K/AKT pathway as a potential therapeutic strategy for β-thalassemia. PMID:29099866

Involvement of PI3K/Akt/FoxO3a and PKA/CREB Signaling Pathways in the Protective Effect of Fluoxetine Against Corticosterone-Induced Cytotoxicity in PC12 Cells.

PubMed

Zeng, Bingqing; Li, Yiwen; Niu, Bo; Wang, Xinyi; Cheng, Yufang; Zhou, Zhongzhen; You, Tingting; Liu, Yonggang; Wang, Haitao; Xu, Jiangping

2016-08-01

The selective serotonin reuptake inhibitor fluoxetine is neuroprotective in several brain injury models. It is commonly used to treat major depressive disorder and related conditions, but its mechanism of action remains incompletely understood. Activation of the phosphatidylinositol-3-kinase/protein kinase B/forkhead box O3a (PI3K/Akt/FoxO3a) and protein kinase A/cAMP-response element binding protein (PKA/CREB) signaling pathways has been strongly implicated in the pathogenesis of depression and might be the downstream target of fluoxetine. Here, we used PC12 cells exposed to corticosterone (CORT) to study the neuroprotective effects of fluoxetine and the involvement of the PI3K/Akt/FoxO3a and PKA/CREB signaling pathways. Our results show that CORT reduced PC12 cells viability by 70 %, and that fluoxetine showed a concentration-dependent neuroprotective effect. Neuroprotective effects of fluoxetine were abolished by inhibition of PI3K, Akt, and PKA using LY294002, KRX-0401, and H89, respectively. Treatment of PC12 cells with fluoxetine resulted in increased phosphorylation of Akt, FoxO3a, and CREB. Fluoxetine also dose-dependently rescued the phosphorylation levels of Akt, FoxO3a, and CREB, following administration of CORT (from 99 to 110, 56 to 170, 80 to 170 %, respectively). In addition, inhibition of PKA and PI3K/Akt resulted in decreased levels of p-CREB, p-Akt, and p-FoxO3a in the presence of fluoxetine. Furthermore, fluoxetine reversed CORT-induced upregulation of p53-upregulated modulator of apoptosis (Puma) and Bcl-2-interacting mediator of cell death (Bim) via the PI3K/Akt/FoxO3a signaling pathway. H89 treatment reversed the effect of fluoxetine on the mRNA level of brain-derived neurotrophic factor, which was decreased in the presence of CORT. Our data indicate that fluoxetine elicited neuroprotection toward CORT-induced cell death that involves dual regulation from PI3K/Akt/FoxO3a and PKA/CREB pathways.

CD25 identifies a subset of CD4⁺FoxP3⁻ TIL that are exhausted yet prognostically favorable in human ovarian cancer.

PubMed

deLeeuw, Ronald J; Kroeger, David R; Kost, Sara E; Chang, Pheh-Ping; Webb, John R; Nelson, Brad H

2015-03-01

CD25, the alpha subunit of the IL2 receptor, is a canonical marker of regulatory T cells (Treg) and hence has been implicated in immune suppression in cancer. However, CD25 is also required for optimal expansion and activity of effector T cells in peripheral tissues. Thus, we hypothesized that CD25, in addition to demarcating Tregs, might identify effector T cells in cancer. To investigate this possibility, we used multiparameter flow cytometry and IHC to analyze tumor-infiltrating lymphocytes (TIL) in primary high-grade serous carcinomas, the most common and fatal subtype of ovarian cancer. CD25 was expressed primarily by CD4⁺ TIL, with negligible expression by CD8⁺ TIL. In addition to conventional CD25⁺FoxP3⁺ Tregs, we identified a subset of CD25⁺FoxP3⁻ T cells that comprised up to 13% of CD4⁺ TIL. In tumors with CD8⁺ TIL, CD25⁺FoxP3⁻ T cells showed a strong positive association with patient survival (HR, 0.56; P = 0.02), which exceeded the negative effect of Tregs (HR, 1.55; P = 0.09). Among CD4⁺ TIL subsets, CD25⁺FoxP3⁻ cells expressed the highest levels of PD-1. Moreover, after in vitro stimulation, they failed to produce common T-helper cytokines (IFNγ, TNFα, IL2, IL4, IL10, or IL17A), suggesting that they were functionally exhausted. In contrast, the more abundant CD25⁻FoxP3⁻ subset of CD4⁺ TIL expressed low levels of PD-1 and produced T-helper 1 cytokines, yet conferred no prognostic benefit. Thus, CD25 identifies a subset of CD4⁺FoxP3⁻ TIL that, despite being exhausted at diagnosis, have a strong, positive association with patient survival and warrant consideration as effector T cells for immunotherapy. ©2014 American Association for Cancer Research.

Myogenesis in the sea urchin embryo: the molecular fingerprint of the myoblast precursors

PubMed Central

2013-01-01

Background In sea urchin larvae the circumesophageal fibers form a prominent muscle system of mesodermal origin. Although the morphology and later development of this muscle system has been well-described, little is known about the molecular signature of these cells or their precise origin in the early embryo. As an invertebrate deuterostome that is more closely related to the vertebrates than other commonly used model systems in myogenesis, the sea urchin fills an important phylogenetic gap and provides a unique perspective on the evolution of muscle cell development. Results Here, we present a comprehensive description of the development of the sea urchin larval circumesophageal muscle lineage beginning with its mesodermal origin using high-resolution localization of the expression of several myogenic transcriptional regulators and differentiation genes. A few myoblasts are bilaterally distributed at the oral vegetal side of the tip of the archenteron and first appear at the late gastrula stage. The expression of the differentiation genes Myosin Heavy Chain, Tropomyosin I and II, as well as the regulatory genes MyoD2, FoxF, FoxC, FoxL1, Myocardin, Twist, and Tbx6 uniquely identify these cells. Interestingly, evolutionarily conserved myogenic factors such as Mef2, MyoR and Six1/2 are not expressed in sea urchin myoblasts but are found in other mesodermal domains of the tip of the archenteron. The regulatory states of these domains were characterized in detail. Moreover, using a combinatorial analysis of gene expression we followed the development of the FoxF/FoxC positive cells from the onset of expression to the end of gastrulation. Our data allowed us to build a complete map of the Non-Skeletogenic Mesoderm at the very early gastrula stage, in which specific molecular signatures identify the precursors of different cell types. Among them, a small group of cells within the FoxY domain, which also express FoxC and SoxE, have been identified as plausible myoblast precursors. Together, these data support a very early gastrula stage segregation of the myogenic lineage. Conclusions From this analysis, we are able to precisely define the regulatory and differentiation signatures of the circumesophageal muscle in the sea urchin embryo. Our findings have important implications in understanding the evolution of development of the muscle cell lineage at the molecular level. The data presented here suggest a high level of conservation of the myogenic specification mechanisms across wide phylogenetic distances, but also reveal clear cases of gene cooption. PMID:24295205

Cutting Edge: Differential Regulation of PTEN by TCR, Akt, and FoxO1 Controls CD4+ T Cell Fate Decisions.

PubMed

Hawse, William F; Sheehan, Robert P; Miskov-Zivanov, Natasa; Menk, Ashley V; Kane, Lawrence P; Faeder, James R; Morel, Penelope A

2015-05-15

Signaling via the Akt/mammalian target of rapamycin pathway influences CD4(+) T cell differentiation; low levels favor regulatory T cell induction and high levels favor Th induction. Although the lipid phosphatase phosphatase and tensin homolog (PTEN) suppresses Akt activity, the control of PTEN activity is poorly studied in T cells. In this study, we identify multiple mechanisms that regulate PTEN expression. During Th induction, PTEN function is suppressed via lower mRNA levels, lower protein levels, and an increase in C-terminal phosphorylation. Conversely, during regulatory T cell induction, PTEN function is maintained through the stabilization of PTEN mRNA transcription and sustained protein levels. We demonstrate that differential Akt/mammalian target of rapamycin signaling regulates PTEN transcription via the FoxO1 transcription factor. A mathematical model that includes multiple modes of PTEN regulation recapitulates our experimental findings and demonstrates how several feedback loops determine differentiation outcomes. Collectively, this work provides novel mechanistic insights into how differential regulation of PTEN controls alternate CD4(+) T cell fate outcomes. Copyright © 2015 by The American Association of Immunologists, Inc.

Insulin-like growth factor 1 rescues R28 retinal neurons from apoptotic death through ERK-mediated BimEL phosphorylation independent of Akt.

PubMed

Kong, Dejuan; Gong, Lijie; Arnold, Edith; Shanmugam, Sumathi; Fort, Patrice E; Gardner, Thomas W; Abcouwer, Steven F

2016-10-01

Insulin-like growth factor 1 (IGF-1) can provide long-term neurotrophic support by activation of Akt, inhibition of FoxO nuclear localization and suppression of Bim gene transcription in multiple neuronal systems. However, MEK/ERK activation can also promote neuron survival through phosphorylation of BimEL. We explored the contribution of the PI3K/Akt/FoxO and MEK/ERK/BimEL pathways in IGF-1 stimulated survival after serum deprivation (SD) of R28 cells differentiated to model retinal neurons. IGF-1 caused rapid activation of Akt leading to FoxO1/3-T32/T24 phosphorylation, and prevented FoxO1/3 nuclear translocation and Bim mRNA upregulation in response to SD. IGF-1 also caused MAPK/MEK pathway activation as indicated by ERK1/2-T202/Y204 and Bim-S65 phosphorylation. Overexpression of FoxO1 increased Bim mRNA expression and amplified the apoptotic response to SD without shifting the serum response curve. Inhibition of Akt activation with LY294002 or by Rictor knockdown did not block the protective effect of IGF-1, while inhibition of MEK activity with PD98059 prevented Bim phosphorylation and blocked IGF-1 protection. In addition, knockdown of Bim expression was protective during SD, while co-silencing of FoxO1 and Fox03 expression had little effect. Thus, the PI3K/Akt/FoxO pathway was not essential for protection from SD-induced apoptosis by IGF-1 in R28 cells. Instead, IGF-1 protection was dependent on activation of the MEK/ERK pathway leading to BimEL phosphorylation, which is known to prevent Bax/Bak oligomerization and activation of the intrinsic mitochondrial apoptosis pathway. These studies demonstrate the requirement of the MEK/ERK pathway in a model of retinal neuron cell survival and highlight the cell specificity for IGF-1 signaling in this response. Copyright © 2016 Elsevier Ltd. All rights reserved.

Elucidating the role of the FoxO3a transcription factor in the IGF-1-induced migration and invasion of uveal melanoma cancer cells.

PubMed

Yan, Fengxia; Liao, Rifang; Farhan, Mohd; Wang, Tinghuai; Chen, Jiashu; Wang, Zhong; Little, Peter J; Zheng, Wenhua

2016-12-01

Uveal melanoma (UM) is the most common primary intraocular malignant tumor of adults. It has high mortality rate due to liver metastasis. However, the epidemiology and pathogenesis of liver metastasis in UM are not elucidated and there is no effective therapy available for preventing the development of this disease. IGF-1 is a growth factor involved in cell proliferation, malignant transformation and inhibition of apoptosis. In previous report, IGF-1 receptor was found to be highly expressed in UM and this was related to tumor prognosis. FoxO3a is a Forkhead box O (FOXO) transcription factor and a downstream target of the IGF-1R/PI3K/Akt pathway involved in a number of physiological and pathological processes including cancer. However, the role of FoxO3a in UM is unknown. In the present study, we investigated fundamental mechanisms in the growth, migration and invasion of UM and the involvement of FoxO3a. IGF-1 increased the cell viability, invasion, migration and S-G2/M cell cycle phase accumulation of UM cells. Western blot analysis showed that IGF-1 led to activation of Akt and concomitant phosphorylation of FoxO3a. FoxO3a phosphorylation was associated with its translocation into the cytoplasm from the nucleus and its functional inhibition led to the inhibition of expression of Bim and p27, but an increase in the expression of Cyclin D1. The effects of IGF-1 on UM cells were reversed by LY294002 (a PI3K inhibitor) or Akt siRNA, and the overexpression of FoxO3a also attenuated basal invasion and migration of UM. Taken all together, these results suggest that inhibition of FoxO3a by IGF-1 via the PI3K/Akt pathway has an important role in IGF-1 induced proliferation and invasion of UM cells. These findings also support FoxO3a and IGF signaling may represent a valid target for investigating the development of new strategies for the treatment and prevention of the pathology of UM. Copyright © 2016. Published by Elsevier Masson SAS.

Variation of lifespan in multiple strains, and effects of dietary restriction and BmFoxO on lifespan in silkworm, Bombyx mori.

PubMed

Song, Jiangbo; Tang, Dongmei; Li, Zhiquan; Tong, Xiaoling; Zhang, Jianfei; Han, Minjin; Hu, Hai; Lu, Cheng; Dai, Fangyin

2017-01-31

Established animal models have accelerated our understanding of the mechanisms involved in lifespan determination. However, more experimental animals are required to clarify the complex mechanisms behind the phenomena of aging and lifespan. In this study, we reported the variation of lifespan in nine distinct silkworm strains. Lifespan correlated significantly with BmFoxO gene expression in the representative silkworm strains tested (Xiafang, Dazao-N, and N4). In general, the female silkworm was longer lived than the male of the same strain. Dietary restriction extended the silkworm lifespan compared with that of silkworms fed ad libitum. The expression of BmFoxO was significantly elevated in the dietary restriction group on day 3 of the 4th instar and day 3 of the 5th instar, suggesting that BmFoxO contributes to dietary restriction-mediated lifespan extension. The RNA interference and overexpression of the BmFoxO gene significantly shortened and extended the silkworm adulthood, respectively. In conclusion, our findings suggest that the silkworm might serve as a promising experimental animal to explore the complex biological mechanisms of lifespan determination.

Licorice flavonoid oil enhances muscle mass in KK-Ay mice.

PubMed

Yoshioka, Yasukiyo; Yamashita, Yoko; Kishida, Hideyuki; Nakagawa, Kaku; Ashida, Hitoshi

2018-07-15

Muscle mass is regulated by the balance between the synthesis and degradation of muscle proteins. Loss of skeletal muscle mass is associated with an increased risk of developing metabolic diseases such as obesity and type 2 diabetes mellitus. The aim of this study was to clarify the effects of licorice flavonoid oil on muscle mass in KK-A y /Ta mice. Male genetically type II diabetic KK-A y /Ta mice received 0, 1, or 1.5 g/kg BW of licorice flavonoid oil by mouth once daily for 4 weeks. After 4 weeks, the femoral and soleus muscles were collected for western blotting for evaluation of the mTOR/p70 S6K, p38/FoxO3a, and Akt/FoxO3a signaling pathways. Ingestion of licorice flavonoid oil significantly enhanced femoral muscle mass without affecting body weight in KK-A y /Ta mice. Licorice flavonoid oil also decreased expression of MuRF1 and atrogin-1, which are both markers of muscle atrophy. The mechanisms by which licorice flavonoid oil enhances muscle mass include activation of mTOR and p70 S6K, and regulation of phosphorylation of FoxO3a. Ingestion of licorice flavonoids may help to prevent muscle atrophy. Copyright © 2018 Elsevier Inc. All rights reserved.

Identification and analysis of evolutionary selection pressures acting at the molecular level in five forkhead subfamilies.

PubMed

Fetterman, Christina D; Rannala, Bruce; Walter, Michael A

2008-09-24

Members of the forkhead gene family act as transcription regulators in biological processes including development and metabolism. The evolution of forkhead genes has not been widely examined and selection pressures at the molecular level influencing subfamily evolution and differentiation have not been explored. Here, in silico methods were used to examine selection pressures acting on the coding sequence of five multi-species FOX protein subfamily clusters; FoxA, FoxD, FoxI, FoxO and FoxP. Application of site models, which estimate overall selection pressures on individual codons throughout the phylogeny, showed that the amino acid changes observed were either neutral or under negative selection. Branch-site models, which allow estimated selection pressures along specified lineages to vary as compared to the remaining phylogeny, identified positive selection along branches leading to the FoxA3 and Protostomia clades in the FoxA cluster and the branch leading to the FoxO3 clade in the FoxO cluster. Residues that may differentiate paralogs were identified in the FoxA and FoxO clusters and residues that differentiate orthologs were identified in the FoxA cluster. Neutral amino acid changes were identified in the forkhead domain of the FoxA, FoxD and FoxP clusters while positive selection was identified in the forkhead domain of the Protostomia lineage of the FoxA cluster. A series of residues under strong negative selection adjacent to the N- and C-termini of the forkhead domain were identified in all clusters analyzed suggesting a new method for refinement of domain boundaries. Extrapolation of domains among cluster members in conjunction with selection pressure information allowed prediction of residue function in the FoxA, FoxO and FoxP clusters and exclusion of known domain function in residues of the FoxA and FoxI clusters. Consideration of selection pressures observed in conjunction with known functional information allowed prediction of residue function and refinement of domain boundaries. Identification of residues that differentiate orthologs and paralogs provided insight into the development and functional consequences of paralogs and forkhead subfamily composition differences among species. Overall we found that after gene duplication of forkhead family members, rapid differentiation and subsequent fixation of amino acid changes through negative selection has occurred.

Diminished FoxP2 levels affect dopaminergic modulation of corticostriatal signaling important to song variability.

PubMed

Murugan, Malavika; Harward, Stephen; Scharff, Constance; Mooney, Richard

2013-12-18

Mutations of the FOXP2 gene impair speech and language development in humans and shRNA-mediated suppression of the avian ortholog FoxP2 disrupts song learning in juvenile zebra finches. How diminished FoxP2 levels affect vocal control and alter the function of neural circuits important to learned vocalizations remains unclear. Here we show that FoxP2 knockdown in the songbird striatum disrupts developmental and social modulation of song variability. Recordings in anesthetized birds show that FoxP2 knockdown interferes with D1R-dependent modulation of activity propagation in a corticostriatal pathway important to song variability, an effect that may be partly attributable to reduced D1R and DARPP-32 protein levels. Furthermore, recordings in singing birds reveal that FoxP2 knockdown prevents social modulation of singing-related activity in this pathway. These findings show that reduced FoxP2 levels interfere with the dopaminergic modulation of vocal variability, which may impede song and speech development by disrupting reinforcement learning mechanisms. Copyright © 2013 Elsevier Inc. All rights reserved.

Diminished FoxP2 levels affect dopaminergic modulation of corticostriatal signaling important to song variability

PubMed Central

Murugan, Malavika; Harward, Stephen; Scharff, Constance; Mooney, Richard

2013-01-01

Summary Mutations of the FOXP2 gene impair speech and language development in humans and shRNA-mediated suppression of the avian orthologue FoxP2 disrupts song learning in juvenile zebra finches. How diminished FoxP2 levels affect vocal control and alter the function of neural circuits important to learned vocalizations remains unclear. Here we show that FoxP2 knockdown in the songbird striatum disrupts developmental and social modulation of song variability. Recordings in anaesthetized birds show that FoxP2 knockdown interferes with D1R-dependent modulation of activity propagation in a corticostriatal pathway important to song variability, an effect that may be partly attributable to reduced D1R and DARPP-32 protein levels. Furthermore, recordings in singing birds reveal that FoxP2 knockdown prevents social modulation of singing-related activity in this pathway. These findings show that reduced FoxP2 levels interfere with the dopaminergic modulation of vocal variability, which may impede song and speech development by disrupting reinforcement learning mechanisms. PMID:24268418

FOX-superroots of Lotus corniculatus, overexpressing Arabidopsis full-length cDNA, show stable variations in morphological traits.

PubMed

Himuro, Yasuyo; Tanaka, Hidenori; Hashiguchi, Masatsugu; Ichikawa, Takanari; Nakazawa, Miki; Seki, Motoaki; Fujita, Miki; Shinozaki, Kazuo; Matsui, Minami; Akashi, Ryo; Hoffmann, Franz

2011-01-15

Using the full-length cDNA overexpressor (FOX) gene-hunting system, we have generated 130 Arabidopsis FOX-superroot lines in bird's-foot trefoil (Lotus corniculatus) for the systematic functional analysis of genes expressed in roots and for the selection of induced mutants with interesting root growth characteristics. We used the Arabidopsis-FOX Agrobacterium library (constructed by ligating pBIG2113SF) for the Agrobacterium-mediated transformation of superroots (SR) and the subsequent selection of gain-of-function mutants with ectopically expressed Arabidopsis genes. The original superroot culture of L. corniculatus is a unique host system displaying fast root growth in vitro, allowing continuous root cloning, direct somatic embryogenesis and mass regeneration of plants under entirely hormone-free culture conditions. Several of the Arabidopsis FOX-superroot lines show interesting deviations from normal growth and morphology of roots from SR-plants, such as differences in pigmentation, growth rate, length or diameter. Some of these mutations are of potential agricultural interest. Genomic PCR analysis revealed that 100 (76.9%) out of the 130 transgenic lines showed the amplification of single fragments. Sequence analysis of the PCR fragments from these 100 lines identified full-length cDNA in 74 of them. Forty-three out of 74 full-length cDNA carried known genes. The Arabidopsis FOX-superroot lines of L. corniculatus, produced in this study, expand the FOX hunting system and provide a new tool for the genetic analysis and control of root growth in a leguminous forage plant. Copyright © 2010 Elsevier GmbH. All rights reserved.

CSP41b, a protein identified via FOX hunting using Eutrema salsugineum cDNAs, improves heat and salinity stress tolerance in transgenic Arabidopsis thaliana.

PubMed

Ariga, Hirotaka; Tanaka, Tomoko; Ono, Hirokazu; Sakata, Yoichi; Hayashi, Takahisa; Taji, Teruaki

2015-08-14

Eutrema salsugineum (also known as Thellungiella salsuginea and formerly Thellungiella halophila), a species closely related to Arabidopsis thaliana, shows tolerance not only to salt stress, but also to chilling, freezing, and high temperatures. To identify genes responsible for stress tolerance, we conducted Full-length cDNA Over-eXpressing gene (FOX) hunting among a collection of E. salsugineum cDNAs that were stress-induced according to gene ontology analysis or over-expressed in E. salsugineum compared with A. thaliana. We identified E. salsugineum CSP41b (chloroplast stem-loop-binding protein of 41 kDa; also known as CRB, chloroplast RNA binding; named here as EsCSP41b) as a gene that can confer heat and salinity stress tolerance on A. thaliana. A. thaliana CSP41b is reported to play an important role in the proper functioning of the chloroplast: the atcsp41b mutant is smaller and paler than wild-type plants and shows altered chloroplast morphology and photosynthetic performance. We observed that AtCSP41b-overexpressing transgenic A. thaliana lines also exhibited marked heat tolerance and significant salinity stress tolerance. The EsCSP41b-overexpressing transgenic A. thaliana lines showed significantly higher photosynthesis activity than wild-type plants not only under normal growth conditions but also under heat stress. In wild-type plants, the expression levels of both EsCSP41b and AtCSP41b were significantly reduced under heat or salinity stress. We conclude that maintenance of CSP41b expression under abiotic stresses may alleviate photoinhibition and improve survival under such stresses. Copyright © 2015 Elsevier Inc. All rights reserved.

T-helper cell type 17/regulatory T-cell immunoregulatory balance in human radicular cysts and periapical granulomas.

PubMed

Marçal, Juliana R B; Samuel, Renata O; Fernandes, Danielle; de Araujo, Marcelo S; Napimoga, Marcelo H; Pereira, Sanivia A L; Clemente-Napimoga, Juliana T; Alves, Polyanna M; Mattar, Rinaldo; Rodrigues, Virmondes; Rodrigues, Denise B R

2010-06-01

Cysts and granulomas are chronic periapical lesions mediated by a set of inflammatory mediators that develop to contain a periapical infection. This study analyzed the nature of the inflammatory infiltrate, presence of mast cells, and in situ expression of cytokines (interleukin [IL]-17 and transforming growth factor [TGF]-beta), chemokines (macrophage inflammatory protein [MIP]-1beta and monocyte chemotactic protein [MCP]-1), and nuclear transcription factor (FoxP3) in human periapical granulomas and cysts compared with a control group. Fifty-five lesions (25 periapical cysts, 25 periapical granulomas, and 5 controls) were analyzed. The type of inflammatory infiltrate was evaluated by hematoxylin-eosin staining, and the presence of mast cells was analyzed by toluidine blue staining. Indirect immunohistochemistry was used to evaluate the expression of cytokines, chemokines, and FoxP3. The inflammatory infiltrate mainly consisted of mononuclear cells. In cysts, mononuclear infiltrates were significantly more frequent than mixed (polymorphonuclear/mononuclear) infiltrates (P = .04). Mixed inflammatory infiltrates were significantly more frequent in patients with sinus tract (P = .0001). The number of mast cells was significantly higher in granulomas than in cystic lesions (P = .02). A significant difference in the expression of IL-17 (P = .001) and TGF-beta (P = .003) was observed between cysts and granulomas and the control group. Significantly higher IL-17 levels were also observed in cases of patients with sinus tract (P = .03). We observed that chronic periapical lesions might experience a reagudization process that is correlated with an increased leukocyte infiltration, with the predominance of neutrophils attracted by a chemokine milieu, as well as the increased presence of IL-17. Copyright 2010 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Deletion of FoxO1, 3, and 4 in Osteoblast Progenitors Attenuates the Loss of Cancellous Bone Mass in a Mouse Model of Type 1 Diabetes

PubMed Central

Iyer, Srividhya; Han, Li; Ambrogini, Elena; Yavropoulou, Maria; Fowlkes, John; Manolagas, Stavros C; Almeida, Maria

2017-01-01

Type 1 diabetes is associated with osteopenia and increased fragility fractures, attributed to reduced bone formation. However, the molecular mechanisms mediating these effects remain unknown. Insulin promotes osteoblast formation and inhibits the activity of the FoxO transcription factors. FoxOs, on the other hand, inhibit osteoprogenitor proliferation and bone formation. Here, we investigated whether FoxOs play a role in the low bone mass associated with type 1 diabetes, using mice lacking FoxO1, 3, and 4 in osteoprogenitor cells (FoxO1,3,4ΔOsx1-Cre). Streptozotocin-induced diabetes caused a reduction in bone mass and strength in FoxO-intact mice. In contrast, cancellous bone was unaffected in diabetic FoxO1,3,4ΔOsx1-Cre mice. The low bone mass in the FoxO-intact diabetic mice was associated with decreased osteoblast number and bone formation, as well as decreased expression of the anti-osteoclastogenic cytokine osteoprotegerin (OPG) and increased osteoclast number. FoxO deficiency did not alter the effects of diabetes on bone formation; however, it did prevent the decrease in OPG and the increase in osteoclast number. Addition of high glucose to osteoblastic cell cultures decreased OPG mRNA, indicating that hyperglycemia in and of itself contributes to diabetic bone loss. Taken together, these results suggest that FoxOs exacerbate the loss of cancellous bone mass associated with type 1 diabetes and that inactivation of FoxOs might ameliorate the adverse effects of insulin deficiency. PMID:27491024

Characterization of mutations in the FOXE1 gene in a cohort of unrelated Malaysian patients with congenital hypothyroidism and thyroid dysgenesis.

PubMed

Kang, In-Nee; Musa, Maslinda; Harun, Fatimah; Junit, Sarni Mat

2010-02-01

The FOXE1 gene was screened for mutations in a cohort of 34 unrelated patients with congenital hypothyroidism, 14 of whom had thyroid dysgenesis and 18 were normal (the thyroid status for 2 patients was unknown). The entire coding region of the FOXE1 gene was PCR-amplified, then analyzed using single-stranded conformational polymorphism, followed by confirmation by direct DNA sequencing. DNA sequencing analysis revealed a heterozygous A>G transition at nucleotide position 394 in one of the patients. The nucleotide transition changed asparagine to aspartate at codon 132 in the highly conserved region of the forkhead DNA binding domain of the FOXE1 gene. This mutation was not detected in a total of 104 normal healthy individuals screened. The binding ability of the mutant FOXE1 protein to the human thyroperoxidase (TPO) promoter was slightly reduced compared with the wild-type FOXE1. The mutation also caused a 5% loss of TPO transcriptional activity.

Uncoupling of acetylation from phosphorylation regulates FoxO1 function independent of its subcellular localization.

PubMed

Qiang, Li; Banks, Alexander S; Accili, Domenico

2010-08-27

The activity of transcription factor FoxO1 is regulated by phosphorylation-dependent nuclear exclusion and deacetylation-dependent nuclear retention. It is unclear whether and how these two post-translational modifications affect each other. To answer this question, we expressed FoxO1 cDNAs with combined mutations of phosphorylation and acetylation sites in HEK-293 cells and analyzed their subcellular localization patterns. We show that mutations mimicking the acetylated state (KQ series) render FoxO1 more sensitive to Akt-mediated phosphorylation and nuclear exclusion and can reverse the constitutively nuclear localization of phosphorylation-defective FoxO1. Conversely, mutations mimicking the deacetylated state (KR series) promote FoxO1 nuclear retention. Oxidative stress and the Sirt1 activator resveratrol are thought to promote FoxO1 deacetylation and nuclear retention, thus increasing its activity. Accordingly, FoxO1 deacetylation was required for the effect of oxidative stress (induced by H(2)O(2)) to retain FoxO1 in the nucleus. H(2)O(2) also inhibited FoxO1 phosphorylation on Ser-253 and Thr-24, the key insulin-regulated sites, irrespective of its acetylation. In contrast, the effect of resveratrol was independent of FoxO1 acetylation and its phosphorylation on Ser-253 and Thr-24, suggesting that resveratrol acts on FoxO1 in a Sirt1- and Akt-independent manner. The dissociation of deacetylation from dephosphorylation in H(2)O(2)-treated cells indicates that the two modifications can occur independently of each other. It can be envisaged that FoxO1 exists in multiple nuclear forms with distinct activities depending on the balance of acetylation and phosphorylation.

RBFOX2 protein domains and cellular activities.

PubMed

Arya, Anurada D; Wilson, David I; Baralle, Diana; Raponi, Michaela

2014-08-01

RBFOX2 (RNA-binding protein, Fox-1 homologue 2)/RBM9 (RNA-binding-motif protein 9)/RTA (repressor of tamoxifen action)/HNRBP2 (hexaribonucleotide-binding protein 2) encodes an RNA-binding protein involved in tissue specific alternative splicing regulation and steroid receptors transcriptional activity. Its ability to regulate specific splicing profiles depending on context has been related to different expression levels of the RBFOX2 protein itself and that of other splicing regulatory proteins involved in the shared modulation of specific genes splicing. However, this cannot be the sole explanation as to why RBFOX2 plays a widespread role in numerous cellular mechanisms from development to cell survival dependent on cell/tissue type. RBFOX2 isoforms with altered protein domains exist. In the present article, we describe the main RBFOX2 protein domains, their importance in the context of splicing and transcriptional regulation and we propose that RBFOX2 isoform distribution may play a fundamental role in RBFOX2-specific cellular effects.

Histone Deacetylase 6 Is a FoxO Transcription Factor-dependent Effector in Skeletal Muscle Atrophy*

PubMed Central

Ratti, Francesca; Ramond, Francis; Moncollin, Vincent; Simonet, Thomas; Milan, Giulia; Méjat, Alexandre; Thomas, Jean-Luc; Streichenberger, Nathalie; Gilquin, Benoit; Matthias, Patrick; Khochbin, Saadi; Sandri, Marco; Schaeffer, Laurent

2015-01-01

Skeletal muscle atrophy is a severe condition of muscle mass loss. Muscle atrophy is caused by a down-regulation of protein synthesis and by an increase of protein breakdown due to the ubiquitin-proteasome system and autophagy activation. Up-regulation of specific genes, such as the muscle-specific E3 ubiquitin ligase MAFbx, by FoxO transcription factors is essential to initiate muscle protein ubiquitination and degradation during atrophy. HDAC6 is a particular HDAC, which is functionally related to the ubiquitin proteasome system via its ubiquitin binding domain. We show that HDAC6 is up-regulated during muscle atrophy. HDAC6 activation is dependent on the transcription factor FoxO3a, and the inactivation of HDAC6 in mice protects against muscle wasting. HDAC6 is able to interact with MAFbx, a key ubiquitin ligase involved in muscle atrophy. Our findings demonstrate the implication of HDAC6 in skeletal muscle wasting and identify HDAC6 as a new downstream target of FoxO3a in stress response. This work provides new insights in skeletal muscle atrophy development and opens interesting perspectives on HDAC6 as a valuable marker of muscle atrophy and a potential target for pharmacological treatments. PMID:25516595

Anoxia-responsive regulation of the FoxO transcription factors in freshwater turtles, Trachemys scripta elegans.

PubMed

Krivoruchko, Anastasia; Storey, Kenneth B

2013-11-01

The forkhead class O (FoxO) transcription factors are important regulators of multiple aspects of cellular metabolism. We hypothesized that activation of these transcription factors could play crucial roles in low oxygen survival in the anoxia-tolerant turtle, Trachemys scripta elegans. Two FoxOs, FoxO1 and FoxO3, were examined in turtle tissues in response to 5 and 20h of anoxic submergence using techniques of RT-PCR, western immunoblotting and DNA-binding assays to assess activation. Transcript levels of FoxO-responsive genes were also quantified using RT-PCR. FoxO1 was anoxia-responsive in the liver, with increases in transcript levels, protein levels, nuclear levels and DNA-binding of 1.7-4.8fold in response to anoxia. Levels of phosphorylated FoxO1 also decreased to 57% of control values in response to 5h of anoxia, indicating activation. FoxO3 was activated in the heart, kidney and liver in response to anoxia, with nuclear levels increasing by 1.5-3.7fold and DNA-binding activity increasing by 1.3-2.9fold. Transcript levels of two FoxO-target genes, p27kip1 and catalase, also rose by 2.4-2.5fold in the turtle liver under anoxia. The results suggest that the FoxO transcription factors are activated in response to anoxia in T. scripta elegans, potentially contributing to the regulation of stress resistance and metabolic depression. This study provides the first demonstration of activation of FoxOs in a natural model for vertebrate anoxia tolerance, further improving understanding of how tissues can survive without oxygen. © 2013.

[Changes of FoxP3, CD4(+)CD25(+) regulatory T cells, TLR2 and TLR9 in children with infectious mononucleosis].

PubMed

Wang, Qiang; Wang, Zuo-Feng; Cao, Mei; Wang, Zhi-Ying

2013-04-01

The aim of this study was to investigate the effects of TLR2, TLR9, CD4(+)CD25(+) regulatory T cells (Treg) and transcription factor FoxP3 in the pathogenesis of children with infectious mononucleosis (IM). Thirty-five acute IM patients admitted in our hospital from April 2010 to January 2011 were enrolled in this study. Thirty-five healthy subjects were taken as control. The thirty-five patients before treatment were considered as patients in acute stage, after treatment and without clinical symptom they were thought as patients in recovery stage. The expression levels of TLR2, TLR9 and FoxP3 mRNA were detected by real time PCR using SYBR Green I. The expression of T lymphocyte subset CD4(+)CD25(+) in peripheral blood mononuclear cells was detected by flow cytometry. The results showed that the relative levels of TLR2 mRNA (4.03 ± 0.56), TLR9 mRNA (8.88 ± 1.56) in peripheral blood mononuclear cells of IM patients in acute stage were significantly higher than those of the controls [TLR2 mRNA (2.22 ± 0.57), TLR9 mRNA (3.63 ± 1.30)] and IM patients in recovery stage [TLR2 mRNA (2.76 ± 0.83), TLR9 mRNA (5.34 ± 1.60)] (P < 0.01). The result of CD4(+)CD25(+) (2.38 ± 1.32%) and relative level of FoxP3 mRNA(2.82 ± 0.90) in peripheral blood mononuclear cells of IM patients in acute stage were lower than those of the control [CD4(+)CD25(+) (7.85 ± 1.97%), FoxP3 mRNA (4.65 ± 1.23) ] (P < 0.01). There was no significant difference in CD4(+)CD25(+) (6.81 ± 1.84%), FoxP3 mRNA(4.11 ± 1.37) levels between IM patients in recovery stage and the controls (P > 0.05). It is concluded that the expression of CD4(+)CD25(+)regulatory T cells is reduced, and its special transcription factor FoxP3 mRNA is down-regulated, but expression levels of TLR2 mRNA, TLR9 mRNA are up-regulated in IM patients of acute stage.

Combining FoxP3 and Helios with GARP/LAP markers can identify expanded Treg subsets in cancer patients.

PubMed

Abd Al Samid, May; Chaudhary, Belal; Khaled, Yazan S; Ammori, Basil J; Elkord, Eyad

2016-03-22

Regulatory T cells (Tregs) comprise numerous heterogeneous subsets with distinct phenotypic and functional features. Identifying Treg markers is critical to investigate the role and clinical impact of various Treg subsets in pathological settings, and also for developing more effective immunotherapies. We have recently shown that non-activated FoxP3-Helios+ and activated FoxP3+/-Helios+ CD4+ T cells express GARP/LAP immunosuppressive markers in healthy donors. In this study we report similar observations in the peripheral blood of patients with pancreatic cancer (PC) and liver metastases from colorectal cancer (LICRC). Comparing levels of different Treg subpopulations in cancer patients and controls, we report that in PC patients, and unlike LICRC patients, there was no increase in Treg levels as defined by FoxP3 and Helios. However, defining Tregs based on GARP/LAP expression showed that FoxP3-LAP+ Tregs in non-activated and activated settings, and FoxP3+Helios+GARP+LAP+ activated Tregs were significantly increased in both groups of patients, compared with controls. This work implies that a combination of Treg-specific markers could be used to more accurately determine expanded Treg subsets and to understand their contribution in cancer settings. Additionally, GARP-/+LAP+ CD4+ T cells made IL-10, and not IFN-γ, and levels of IL-10-secreting CD4+ T cells were elevated in LICRC patients, especially with higher tumor staging. Taken together, our results indicate that investigations of Treg levels in different cancers should consider diverse Treg-related markers such as GARP, LAP, Helios, and others and not only FoxP3 as a sole Treg-specific marker.

Cleavage Mapping the Topology of Protein Folding Intermediates

DTIC Science & Technology

1995-03-13

1993). 29. Nakano, T., Antonino , L. C, Fox, R. O. & Fink, A. L. Effect of proline mutation on the stability and kinetics of folding of...Biochem. 62, 653-683. Nakano, T., Antonino , L. C., Fox, R. O., & Fink, A. L. (1993) Biochemistry 32, 2534-2541. Nozaki, Y. (1972) Methods Enzymol. 26, 43

Dynamic Regulation of FoxA1 by Steroid Receptors | Center for Cancer Research

Cancer.gov

The estrogen receptor (ER) is a key regulator in breast cancer initiation and progression. A widely discussed model proposes that forkhead box protein A1 (FoxA1) acts as a pioneer factor in cancer by binding and penetrating closed chromatin to allow access by transcription factors (TFs), including ER.

Knockdown of FoxP2 alters spine density in Area X of the zebra finch.

PubMed

Schulz, S B; Haesler, S; Scharff, C; Rochefort, C

2010-10-01

Mutations in the gene encoding the transcription factor FoxP2 impair human speech and language. We have previously shown that deficits in vocal learning occur in zebra finches after reduction of FoxP2 in Area X, a striatal nucleus involved in song acquisition. We recently showed that FoxP2 is expressed in newly generated spiny neurons (SN) in adult Area X as well as in the ventricular zone (VZ) from which the SN originates. Moreover, their recruitment to Area X increases transiently during the song learning phase. The present report therefore investigated whether FoxP2 is involved in the structural plasticity of Area X. We assessed the proliferation, differentiation and morphology of SN after lentivirally mediated knockdown of FoxP2 in Area X or in the VZ during the song learning phase. Proliferation rate was not significantly affected by knockdown of FoxP2 in the VZ. In addition, FoxP2 reduction both in the VZ and in Area X did not affect the number of new neurons in Area X. However, at the fine-structural level, SN in Area X bore fewer spines after FoxP2 knockdown. This effect was even more pronounced when neurons received the knockdown before differentiation, i.e. as neuroblasts in the VZ. These results suggest that FoxP2 might directly or indirectly regulate spine dynamics in Area X and thereby influence song plasticity. Together, these data present the first evidence for a role of FoxP2 in the structural plasticity of dendritic spines and complement the emerging evidence of physiological synaptic plasticity in FoxP2 mouse models. Genes, Brain and Behavior © 2010 Blackwell Publishing Ltd and International Behavioural and Neural Genetics Society. No claim to original US government works.

Detection of specific antibody responses to vaccination in variable flying foxes (Pteropus hypomelanus).

PubMed

Wellehan, James F X; Green, Linda G; Duke, Diane G; Bootorabi, Shadi; Heard, Darryl J; Klein, Paul A; Jacobson, Elliott R

2009-09-01

Megachiropteran bats are biologically important both as endangered species and reservoirs for emerging human pathogens. Reliable detection of antibodies to specific pathogens in bats is thus epidemiologically critical. Eight variable flying foxes (Pteropus hypomelanus) were immunized with 2,4-dinitrophenylated bovine serum albumin (DNP-BSA). Each bat received monthly inoculations for 2 months. Affinity-purified IgG was used for production of polyclonal and monoclonal anti-variable flying fox IgG antibodies. ELISA and western blot analysis were used to monitor immune responses and for assessment of polyclonal and monoclonal antibody species cross-reactivity. Protein G, polyclonal antibodies, and monoclonal antibodies detected specific anti-DNP antibody responses in immunized variable flying foxes, with protein G being the most sensitive, followed by monoclonal antibodies and then polyclonal antibodies. While the polyclonal antibody was found to cross-react well against IgG of all bat species tested, some non-specific background was observed. The monoclonal antibody was found to cross-react well against IgG of six other species in the genus Pteropus and to cross-react less strongly against IgG from Eidolon helvum or Phyllostomus hastatus. Protein G distinguished best between vaccinated and unvaccinated bats, and these results validate the use of protein G for detection of bat IgG. Monoclonal antibodies developed in this study recognized immunoglobulins from other members of the genus Pteropus well, and may be useful in applications where specific detection of Pteropus IgG is needed.

Transforming growth factor-beta and Forkhead box O transcription factors as cardiac fibroblast regulators.

PubMed

Norambuena-Soto, Ignacio; Núñez-Soto, Constanza; Sanhueza-Olivares, Fernanda; Cancino-Arenas, Nicole; Mondaca-Ruff, David; Vivar, Raul; Díaz-Araya, Guillermo; Mellado, Rosemarie; Chiong, Mario

2017-05-23

Fibroblasts play several homeostatic roles, including electrical coupling, paracrine signaling and tissue repair after injury. Fibroblasts have low secretory activity. However, in response to injury, they differentiate to myofibroblasts. These cells have an increased extracellular matrix synthesis and secretion, including collagen fibers, providing stiffness to the tissue. In pathological conditions myofibroblasts became resistant to apoptosis, remaining in the tissue, causing excessive extracellular matrix secretion and deposition, which contributes to the progressive tissue remodeling. Therefore, increased myofibroblast content within damaged tissue is a characteristic hallmark of heart, lung, kidney and liver fibrosis. Recently, it was described that cardiac fibroblast to myofibroblast differentiation is triggered by the transforming growth factor β1 (TGF-β1) through a Smad-independent activation of Forkhead box O (FoxO). FoxO proteins are a transcription factor family that includes FoxO1, FoxO3, FoxO4 and FoxO6. In several cells types, they play an important role in cell cycle arrest, oxidative stress resistance, cell survival, energy metabolism, and cell death. Here, we review the role of FoxO family members on the regulation of cardiac fibroblast proliferation and differentiation.

Recombinant ESAT-6-CFP10 Fusion Protein Induction of Th1/Th2 Cytokines and FoxP3 Expressing Treg Cells in Pulmonary TB

PubMed Central

Jackson-Sillah, Dolly; Cliff, Jacqueline M.; Mensah, Gloria Ivy; Dickson, Emmanuel; Sowah, Sandra; Tetteh, John K A.; Addo, Kwasi K.; Ottenhoff, Tom H. M.; Bothamley, Graham; Dockrell, Hazel M.

2013-01-01

Background Early secretory antigenic target 6 (ESAT-6) and culture filtrate protein 10 (CFP-10) are Mycobacterium tuberculosis (Mtb)–specific antigens that are secreted by actively metabolising bacteria and contribute to the virulence of the bacteria. Their ability to induce Treg and Th2 responses, particularly during the first two weeks of treatment, has not been comprehensively examined to date. The purpose of this work was to characterise Th1, Th2 and Treg responses to rESAT-6-CFP10 fusion protein in TB patients before and during the intensive phase of treatment and in healthy M.bovis BCG vaccinated donors. Methods Forty-six newly diagnosed, HIV-negative, smear-positive pulmonary TB patients and 20 healthy donors were recruited in the UK and Ghana. Their peripheral blood mononuclear cells (PBMC) were used in ex vivo ELISPOT and in vitro cultures to identify immunological parameters of interest. Results The study confirmed that protective immune responses to rESAT-6-CFP10 are impaired in active TB but improved during treatment: circulating antigen-specific IL-4-producing T-cells were increased in untreated TB but declined by two weeks of treatment while the circulating antigen-specific IFN-γ producing T cells which showed a transient rise at one week of treatment, persisted at baseline levels at two months of treatment. In vitro T cell proliferation and IFN-γ production were reduced, while IL-4 and CD4+FoxP3+CD25hi cell expression were increased in response to rESAT-6-CFP10 fusion protein in untreated TB. These responses were reversed during early treatment of TB. Conclusions These observations support further investigations into the possible utility of these parameters as markers of active disease and favourable treatment outcomes. PMID:23826366

Phosphoproteome analysis reveals a critical role for hedgehog signalling in osteoblast morphological transitions.

PubMed

Marumoto, Ariane; Milani, Renato; da Silva, Rodrigo A; da Costa Fernandes, Célio Junior; Granjeiro, José Mauro; Ferreira, Carmen V; Peppelenbosch, Maikel P; Zambuzzi, Willian F

2017-10-01

The reciprocal and adaptive interactions between cells and substrates governing morphological transitions in the osteoblast compartment remain largely obscure. Here we show that osteoblast cultured in basement membrane matrix (Matrigel™) exhibits significant morphological changes after ten days of culture, and we decided to exploit this situation to investigate the molecular mechanisms responsible for guiding osteoblast morphological transitions. As almost all aspects of cellular physiology are under control of kinases, we generated more or less comprehensive cellular kinome profiles employing PepChip peptide arrays that contain over 1000 consensus substrates of kinase peptide. The results obtained were used to construct interactomes, and these revealed an important role for FoxO in mediating morphological changes of osteoblast, which was validated by Western blot technology when FoxO was significantly up-expressed in response to Matrigel™. As FoxO is a critical protein in canonical hedgehog signalling, we decided to explore the possible involvement of hedgehog signalling during osteoblast morphological changes. It appeared that osteoblast culture in Matrigel™ stimulates release of a substantial amounts Shh while concomitantly inducing upregulation of the expression of the bona fide hedgehog target genes Gli-1 and Patched. Functional confirmation of the relevance of these results for osteoblast morphological transitions came from experiments in which Shh hedgehog signalling was inhibited using the well-established pathway inhibitor cyclopamine (Cyc). In the presence of Cyc, culture of osteoblasts in Matrigel™ is not capable of inducing morphological changes but appears to provoke a proliferative response as evident from the upregulation of Cyclin D3 and cdk4. The most straightforward interpretation of our results is that hedgehog signalling is both necessary and sufficient for membrane matrix-based morphological transitions. Copyright © 2017 Elsevier Inc. All rights reserved.

Membrane Type 1–Matrix Metalloproteinase/Akt Signaling Axis Modulates TNF-α-Induced Procoagulant Activity and Apoptosis in Endothelial Cells

PubMed Central

Ohkawara, Hiroshi; Ishibashi, Toshiyuki; Sugimoto, Koichi; Ikeda, Kazuhiko; Ogawa, Kazuei; Takeishi, Yasuchika

2014-01-01

Membrane type 1–matrix metalloproteinase (MT1-MMP) functions as a signaling molecule in addition to a proteolytic enzyme. Our hypothesis was that MT1-MMP cooperates with protein kinase B (Akt) in tumor necrosis factor (TNF)-α-induced signaling pathways of vascular responses, including tissue factor (TF) procoagulant activity and endothelial apoptosis, in cultured human aortic endothelial cells (ECs). TNF-α (10 ng/mL) induced a decrease in Akt phosphorylation within 60 minutes in ECs. A chemical inhibitor of MMP, TIMP-2 and selective small interfering RNA (siRNA)-mediated suppression of MT1-MMP reversed TNF-α-triggered transient decrease of Akt phosphorylation within 60 minutes, suggesting that MT1-MMP may be a key regulator of Akt phosphorylation in TNF-α-stimulated ECs. In the downstream events, TNF-α increased TF antigen and activity, and suppressed the expression of thrombomodulin (TM) antigen. Inhibition of Akt markedly enhanced TNF-α-induced expression of TF antigen and activity, and further reduced the expression of TM antigen. Silencing of MT1-MMP by siRNA also reversed the changed expression of TF and TM induced by TNF-α. Moreover, TNF-α induced apoptosis of ECs through Akt- and forkhead box protein O1 (FoxO1)-dependent signaling pathway and nuclear factor-kB (NF-kB) activation. Knockdown of MT1-MMP by siRNA reversed apoptosis of ECs by inhibiting TNF-α-induced Akt-dependent regulation of FoxO1 in TNF-α-stimulated ECs. Immunoprecipitation demonstrated that TNF-α induced the changes in the associations between the cytoplasmic fraction of MT1-MMP and Akt in ECs. In conclusion, we show new evidence that MT1-MMP/Akt signaling axis is a key modifier for TNF-α-induced signaling pathways for modulation of procoagulant activity and apoptosis of ECs. PMID:25162582

Transcriptome Profiling of Human FoxP3+ Regulatory T Cells

PubMed Central

Bhairavabhotla, Ravikiran; Kim, Yong C.; Glass, Deborah D.; Escobar, Thelma M.; Patel, Mira C.; Zahr, Rami; Nguyen, Cuong K.; Kilaru, Gokhul K.; Muljo, Stefan A.; Shevach, Ethan M.

2015-01-01

The major goal of this study was to perform an in depth characterization of the “gene signature” of human FoxP3+ T regulatory cells (Tregs). Highly purified Tregs and T conventional cells (Tconvs) from multiple healthy donors (HD), either freshly explanted or activated in vitro, were analyzed via RNA sequencing (RNA-seq) and gene expression changes validated using the nCounter system. Additionally, we analyzed microRNA (miRNA) expression using TaqMan low-density arrays. Our results confirm previous studies demonstrating selective gene expression of FoxP3, IKZF2, and CTLA4 in Tregs. Notably, a number of yet uncharacterized genes (RTKN2, LAYN, UTS2, CSF2RB, TRIB1, F5, CECAM4, CD70, ENC1 and NKG7) were identified and validated as being differentially expressed in human Tregs. We further characterize the functional roles of RTKN2 and LAYN by analyzing their roles in vitro human Treg suppression assays by knocking them down in Tregs and overexpressing them in Tconvs. In order to facilitate a better understanding of the human Treg gene expression signature, we have generated from our results a hypothetical interactome of genes and miRNAs in Tregs and Tconvs, PMID:26686412

Characterization of B61, the ligand for the Eck receptor protein-tyrosine kinase.

PubMed

Shao, H; Pandey, A; O'Shea, K S; Seldin, M; Dixit, V M

1995-03-10

B61 was originally described as a novel secreted tumor necrosis factor-alpha-inducible gene product in endothelial cells (Holzman, L. B., Marks, R. M., and Dixit, V. M. (1990) Mol. Cell. Biol. 10, 5830-5838). It was recently discovered that soluble recombinant B61 could serve as a ligand for the Eck receptor protein-tyrosine kinase, a member of the Eph/Eck subfamily of receptor protein-tyrosine kinases (Bartley, T.D., Hunt, R. W., Welcher, A. A., Boyle, W. J., Parker, V. P., Lindberg, R. A., Lu, H. S., Colombero, A. M., Elliott, R. L., Guthrie, R. A., Holst, P. L., Skrine, J. D., Toso, R. J., Zhang, M., Fernandez, E., Trail, G., Yarnum, B., Yarden, Y., Hunter, T., and Fox, G. M. (1994) Nature 368, 558-560). We now show that B61 can also exist as a cell surface glycosylphosphatidyl-inositol-linked protein that is capable of activating the Eck receptor protein-tyrosine kinase, the first such report of a receptor protein-tyrosine kinase ligand that is glycosylphosphatidylinositol-linked. In addition, the expression patterns of B61 and Eck during mouse ontogeny were determined by in situ hybridization. Both were found to be highly expressed in the developing lung and gut, while Eck was preferentially expressed in the thymus. Finally, the gene for B61 was localized to a specific position on mouse chromosome 3 by interspecific back-cross analysis.

Myocardial Gene Expression of T-bet, GATA-3, Ror-γt, FoxP3, and Hallmark Cytokines in Chronic Chagas Disease Cardiomyopathy: An Essentially Unopposed TH1-Type Response

PubMed Central

Nogueira, Luciana Gabriel; Santos, Ronaldo Honorato Barros; Fiorelli, Alfredo Inácio; Mairena, Eliane Conti; Benvenuti, Luiz Alberto; Bocchi, Edimar Alcides; Stolf, Noedir Antonio; Kalil, Jorge; Cunha-Neto, Edecio

2014-01-01

Background. Chronic Chagas disease cardiomyopathy (CCC), a late consequence of Trypanosoma cruzi infection, is an inflammatory cardiomyopathy with prognosis worse than those of noninflammatory etiology (NIC). Although the T cell-rich myocarditis is known to play a pathogenetic role, the relative contribution of each of the functional T cell subsets has never been thoroughly investigated. We therefore assessed gene expression of cytokines and transcription factors involved in differentiation and effector function of each functional T cell subset (TH1/TH2/TH17/Treg) in CCC, NIC, and heart donor myocardial samples. Methods and Results. Quantitative PCR showed markedly upregulated expression of IFN-γ and transcription factor T-bet, and minor increases of GATA-3; FoxP3 and CTLA-4; IL-17 and IL-18 in CCC as compared with NIC samples. Conversely, cytokines expressed by TH2 cells (IL-4, IL-5, and IL-13) or associated with Treg (TGF-β and IL-10) were not upregulated in CCC myocardium. Expression of TH1-related genes such as T-bet, IFN-γ, and IL-18 correlated with ventricular dilation, FoxP3, and CTLA-4. Conclusions. Results are consistent with a strong local TH1-mediated response in most samples, possibly associated with pathological myocardial remodeling, and a proportionally smaller FoxP3+CTLA4+ Treg cell population, which is unable to completely curb IFN-γ production in CCC myocardium, therefore fueling inflammation. PMID:25152568

FoxP2 is a Parvocellular-Specific Transcription Factor in the Visual Thalamus of Monkeys and Ferrets

PubMed Central

Iwai, Lena; Ohashi, Yohei; van der List, Deborah; Usrey, William Martin; Miyashita, Yasushi; Kawasaki, Hiroshi

2013-01-01

Although the parallel visual pathways are a fundamental basis of visual processing, our knowledge of their molecular properties is still limited. Here, we uncovered a parvocellular-specific molecule in the dorsal lateral geniculate nucleus (dLGN) of higher mammals. We found that FoxP2 transcription factor was specifically expressed in X cells of the adult ferret dLGN. Interestingly, FoxP2 was also specifically expressed in parvocellular layers 3–6 of the dLGN of adult old world monkeys, providing new evidence for a homology between X cells in the ferret dLGN and parvocellular cells in the monkey dLGN. Furthermore, this expression pattern was established as early as gestation day 140 in the embryonic monkey dLGN, suggesting that parvocellular specification has already occurred when the cytoarchitectonic dLGN layers are formed. Our results should help in gaining a fundamental understanding of the development, evolution, and function of the parallel visual pathways, which are especially prominent in higher mammals. PMID:22791804

Diarylheptanoids suppress proliferation of pancreatic cancer PANC-1 cells through modulating shh-Gli-FoxM1 pathway.

PubMed

Dong, Guang-Zhi; Jeong, Ji Hye; Lee, Yu-Ih; Lee, So Yoon; Zhao, Hui-Yuan; Jeon, Raok; Lee, Hwa Jin; Ryu, Jae-Ha

2017-04-01

Pancreatic cancer is one of the leading causes of cancer, and it has the lowest 5-year survival rates. It is necessary to develop more potent anti-pancreatic cancer drugs to overcome the fast metastasis and resistance to surgery, radiotherapy, chemotherapy, and combinations of these. We have identified several diarylheptanoids as anti-pancreatic cancer agents from Alpinia officinarum (lesser galangal) and Alnus japonica. These diarylheptanoids suppressed cell proliferation and induced the cell cycle arrest of pancreatic cancer cells (PANC-1). Among them, the most potent compounds 1 and 7 inhibited the shh-Gli-FoxM1 pathway and their target gene expression in PANC-1 cells. Furthermore, they suppressed the expression of the cell cycle associated genes that were rescued by the overexpression of exogenous FoxM1. Taken together, (E)-7-(4-hydroxy-3-methoxyphenyl)-1-phenylhept-4-en-3-one (1) from Alpinia officinarum (lesser galangal) and platyphyllenone (7) from Alnus japonica inhibit PANC-1 cell proliferation by suppressing the shh-Gli-FoxM1 pathway, and they can be potential candidates for anti-pancreatic cancer drug development.

Neural crest specification and migration independently require NSD3-related lysine methyltransferase activity

PubMed Central

Jacques-Fricke, Bridget T.; Gammill, Laura S.

2014-01-01

Neural crest precursors express genes that cause them to become migratory, multipotent cells, distinguishing them from adjacent stationary neural progenitors in the neurepithelium. Histone methylation spatiotemporally regulates neural crest gene expression; however, the protein methyltransferases active in neural crest precursors are unknown. Moreover, the regulation of methylation during the dynamic process of neural crest migration is unclear. Here we show that the lysine methyltransferase NSD3 is abundantly and specifically expressed in premigratory and migratory neural crest cells. NSD3 expression commences before up-regulation of neural crest genes, and NSD3 is necessary for expression of the neural plate border gene Msx1, as well as the key neural crest transcription factors Sox10, Snail2, Sox9, and FoxD3, but not gene expression generally. Nevertheless, only Sox10 histone H3 lysine 36 dimethylation requires NSD3, revealing unexpected complexity in NSD3-dependent neural crest gene regulation. In addition, by temporally limiting expression of a dominant negative to migratory stages, we identify a novel, direct requirement for NSD3-related methyltransferase activity in neural crest migration. These results identify NSD3 as the first protein methyltransferase essential for neural crest gene expression during specification and show that NSD3-related methyltransferase activity independently regulates migration. PMID:25318671

Paeoniflorin inhibits cell growth and induces cell cycle arrest through inhibition of FoxM1 in colorectal cancer cells.

PubMed

Yue, Meng; Li, Shiquan; Yan, Guoqiang; Li, Chenyao; Kang, Zhenhua

2018-01-01

Paeoniflorin (PF) exhibits tumor suppressive functions in a variety of human cancers. However, the function of PF and molecular mechanism in colorectal cancer are elusive. In the present study, we investigated whether PF could exert its antiproliferative activity, anti-migration, and anti-invasive function in colorectal cancer cells. We found that PF inhibited cell growth and induced apoptosis and blocked cell cycle progression in the G0/G1 phase in colorectal cancer cells. Moreover, we found that PF suppressed cell migration and invasion in colorectal cancer cells. FoxM1 has been reported to play an important oncogenic role in human cancers. We also determine whether PF inhibited the expression of FoxM1, leading to its anti-cancer activity. We found that PF treatment in colorectal cancer cells resulted in down-regulation of FoxM1. The rescue experiments showed that overexpression of FoxM1 abrogated the tumor suppressive function induced by PF treatment. Notably, depletion of FoxM1 promoted the anti-tumor activity of PF in colorectal cancer cells. Therefore, inhibition of FoxM1 could participate in the anti-tumor activity of PF in colorectal cancer cells.

Specific detection of Echinococcus spp. from the Tibetan fox (Vulpes ferrilata) and the red fox (V. vulpes) using copro-DNA PCR analysis.

PubMed

Jiang, Weibin; Liu, Nan; Zhang, Gaotian; Renqing, Pengcuo; Xie, Fei; Li, Tiaoying; Wang, Zhenghuan; Wang, Xiaoming

2012-10-01

There are three Echinococcus species, Echinococcus granulosus, E. multilocularis, and E. shiquicus, which are distributed on the vast area of pastureland on the eastern Tibetan plateau in China. Tibetan foxes (Vulpes ferrilata) have been determined to be the main wild definitive host of E. multilocularis and E. shiquicus, but little information is available on the prevalence of these two parasites in Tibetan foxes. Consequently, the copro-prevalence of these parasites in foxes from the eastern Tibetan plateau was evaluated in this study. For each copro-DNA sample extracted from fox feces, a 133-bp segment of EgG1 Hae III was used to screen for infection with E. granulosus. Multiplex nested polymerase chain reaction (PCR) analysis was used to target an 874-bp segment of the mitochondrial COI gene to distinguish E. multilocularis and E. shiquicus. Among 184 fecal samples, 120 were from Tibetan foxes and six from red foxes (Vulpes vulpes). Of the fecal samples from Tibetan foxes, 74 (giving a copro-prevalence of 62%) showed the presence of Echinococcus spp.: 23 (19%) were found to contain E. multilocularis, 32 (27%) E. shiquicus, and 19 (16%) showed mixed infection with both E. multilocularis and E. shiquicus. Two fecal samples from red foxes were found to be infected with E. multilocularis. No fox feces were found to be infected with E. granulosus. Tests on zinc finger protein genes and a 105-bp fragment of the Sry gene found no significant difference in the prevalence of the two parasites between sexes. The efficiency of our multiplex nested PCR methods were compared with previous polymerase chain reaction-based restriction fragment length polymorphism (PCR-RFLP) methods and some problems associated with the copro-PCR were discussed.

Adenovirus Protein E4-ORF1 Activation of PI3 Kinase Reveals Differential Regulation of Downstream Effector Pathways in Adipocytes.

PubMed

Chaudhary, Natasha; Gonzalez, Eva; Chang, Sung-Hee; Geng, Fuqiang; Rafii, Shahin; Altorki, Nasser K; McGraw, Timothy E

2016-12-20

Insulin activation of phosphatidylinositol 3-kinase (PI3K) regulates metabolism, including the translocation of the Glut4 glucose transporter to the plasma membrane and inactivation of the FoxO1 transcription factor. Adenoviral protein E4-ORF1 stimulates cellular glucose metabolism by mimicking growth-factor activation of PI3K. We have used E4-ORF1 as a tool to dissect PI3K-mediated signaling in adipocytes. E4-ORF1 activation of PI3K in adipocytes recapitulates insulin regulation of FoxO1 but not regulation of Glut4. This uncoupling of PI3K effects occurs despite E4-ORF1 activating PI3K and downstream signaling to levels achieved by insulin. Although E4-ORF1 does not fully recapitulate insulin's effects on Glut4, it enhances insulin-stimulated insertion of Glut4-containing vesicles to the plasma membrane independent of Rab10, a key regulator of Glut4 trafficking. E4-ORF1 also stimulates plasma membrane translocation of ubiquitously expressed Glut1 glucose transporter, an effect that is likely essential for E4-ORF1 to promote an anabolic metabolism in a broad range of cell types. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

Rapid Nuclear Exclusion of Hcm1 in Aging Saccharomyces cerevisiae Leads to Vacuolar Alkalization and Replicative Senescence

PubMed Central

Ghavidel, Ata; Baxi, Kunal; Prusinkiewicz, Martin; Swan, Cynthia; Belak, Zach R.; Eskiw, Christopher H.; Carvalho, Carlos E.; Harkness, Troy A.

2018-01-01

The yeast, Saccharomyces cerevisiae, like other higher eukaryotes, undergo a finite number of cell divisions before exiting the cell cycle due to the effects of aging. Here, we show that yeast aging begins with the nuclear exclusion of Hcm1 in young cells, resulting in loss of acidic vacuoles. Autophagy is required for healthy aging in yeast, with proteins targeted for turnover by autophagy directed to the vacuole. Consistent with this, vacuolar acidity is necessary for vacuolar function and yeast longevity. Using yeast genetics and immunofluorescence microscopy, we confirm that vacuolar acidity plays a critical role in cell health and lifespan, and is potentially maintained by a series of Forkhead Box (Fox) transcription factors. An interconnected transcriptional network involving the Fox proteins (Fkh1, Fkh2 and Hcm1) are required for transcription of v-ATPase subunits and vacuolar acidity. As cells age, Hcm1 is rapidly excluded from the nucleus in young cells, blocking the expression of Hcm1 targets (Fkh1 and Fkh2), leading to loss of v-ATPase gene expression, reduced vacuolar acidification, increased α-syn-GFP vacuolar accumulation, and finally, diminished replicative lifespan (RLS). Loss of vacuolar acidity occurs about the same time as Hcm1 nuclear exclusion and is conserved; we have recently demonstrated that lysosomal alkalization similarly contributes to aging in C. elegans following a transition from progeny producing to post-reproductive life. Our data points to a molecular mechanism regulating vacuolar acidity that signals the end of RLS when acidification is lost. PMID:29519938

Paramyosin from the parasitic mite Sarcoptes scabiei: cDNA cloning and heterologous expression.

PubMed

Mattsson, J G; Ljunggren, E L; Bergström, K

2001-05-01

The burrowing mite Sarcoptes scabiei is the causative agent of the highly contagious disease sarcoptic mange or scabies. So far, there is no in vitro propagation system for S. scabiei available, and mites used for various purposes must be isolated from infected hosts. Lack of parasite-derived material has limited the possibilities to study several aspects of scabies, including pathogenesis and immunity. It has also hampered the development of high performance serological assays. We have now constructed an S. scabiei cDNA expression library with mRNA purified from mites isolated from red foxes. Immunoscreening of the library enabled us to clone a full-length cDNA coding for a 102.5 kDa protein. Sequence similarity searches identified the protein as a paramyosin. Recombinant S. scabiei paramyosin expressed in Escherichia coli was recognized by sera from dogs and swine infected with S. scabiei. We also designed a small paramyosin construct of about 17 kDa that included the N-terminal part, an evolutionary variable part of the helical core, and the C-terminal part of the molecule. The miniaturized protein was efficiently expressed in E. coli and was recognized by sera from immunized rabbits. These data demonstrate that the cDNA library can assist in the isolation of important S. scabiei antigens and that recombinant proteins can be useful for the study of scabies.

Analysis of ZP1 gene reveals differences in zona pellucida composition in carnivores.

PubMed

Moros-Nicolás, C; Leza, A; Chevret, P; Guillén-Martínez, A; González-Brusi, L; Boué, F; Lopez-Bejar, M; Ballesta, J; Avilés, M; Izquierdo-Rico, M J

2018-01-01

The zona pellucida (ZP) is an extracellular envelope that surrounds mammalian oocytes. This coat participates in the interaction between gametes, induction of the acrosome reaction, block of polyspermy and protection of the oviductal embryo. Previous studies suggested that carnivore ZP was formed by three glycoproteins (ZP2, ZP3 and ZP4), with ZP1 being a pseudogene. However, a recent study in the cat found that all four proteins were expressed. In the present study, in silico and molecular analyses were performed in several carnivores to clarify the ZP composition in this order of mammals. The in silico analysis demonstrated the presence of the ZP1 gene in five carnivores: cheetah, panda, polar bear, tiger and walrus, whereas in the Antarctic fur seal and the Weddell seal there was evidence of pseudogenisation. Molecular analysis showed the presence of four ZP transcripts in ferret ovaries (ZP1, ZP2, ZP3 and ZP4) and three in fox ovaries (ZP2, ZP3 and ZP4). Analysis of the fox ZP1 gene showed the presence of a stop codon. The results strongly suggest that all four ZP genes are expressed in most carnivores, whereas ZP1 pseudogenisation seems to have independently affected three families (Canidae, Otariidae and Phocidae) of the carnivore tree.

A winged helix forkhead (FOXD2) tunes sensitivity to cAMP in T lymphocytes through regulation of cAMP-dependent protein kinase RIalpha.

PubMed

Johansson, C Christian; Dahle, Maria K; Blomqvist, Sandra Rodrigo; Grønning, Line M; Aandahl, Einar M; Enerbäck, Sven; Taskén, Kjetil

2003-05-09

Forkhead/winged helix (FOX) transcription factors are essential for control of the cell cycle and metabolism. Here, we show that spleens from Mf2-/- (FOXD2-/-) mice have reduced mRNA (50%) and protein (35%) levels of the RIalpha subunit of the cAMP-dependent protein kinase. In T cells from Mf2-/- mice, reduced levels of RIalpha translates functionally into approximately 2-fold less sensitivity to cAMP-mediated inhibition of proliferation triggered through the T cell receptor-CD3 complex. In Jurkat T cells, FOXD2 overexpression increased the endogenous levels of RIalpha through induction of the RIalpha1b promoter. FOXD2 overexpression also increased the sensitivity of the promoter to cAMP. Finally, co-expression experiments demonstrated that protein kinase Balpha/Akt1 work together with FOXD2 to induce the RIalpha1b promoter (10-fold) and increase endogenous RIalpha protein levels further. Taken together, our data indicate that FOXD2 is a physiological regulator of the RIalpha1b promoter in vivo working synergistically with protein kinase B to induce cAMP-dependent protein kinase RIalpha expression, which increases cAMP sensitivity and sets the threshold for cAMP-mediated negative modulation of T cell activation.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang Bo; Huang Bo; School of Public Health, University of South China, Hengyang, Hunan 421001

Mitotic catastrophe, a form of cell death resulting from abnormal mitosis, is a cytotoxic death pathway as well as an appealing mechanistic strategy for the development of anti-cancer drugs. In this study, 6-bromine-5-hydroxy-4-methoxybenzaldehyde was demonstrated to induce DNA double-strand break, multipolar spindles, sustain mitotic arrest and generate multinucleated cells, all of which indicate mitotic catastrophe, in human hepatoma HepG2 cells. We used proteomic profiling to identify the differentially expressed proteins underlying mitotic catastrophe. A total of 137 differentially expressed proteins (76 upregulated and 61 downregulated proteins) were identified. Some of the changed proteins have previously been associated with mitotic catastrophe,more » such as DNA-PKcs, FoxM1, RCC1, cyclin E, PLK1-pT210, 14-3-3{sigma} and HSP70. Multiple isoforms of 14-3-3, heat-shock proteins and tubulin were upregulated. Analysis of functional significance revealed that the 14-3-3-mediated signaling network was the most significantly enriched for the differentially expressed proteins. The modulated proteins were found to be involved in macromolecule complex assembly, cell death, cell cycle, chromatin remodeling and DNA repair, tubulin and cytoskeletal organization. These findings revealed the overall molecular events and functional signaling networks associated with spindle disruption and mitotic catastrophe. - Graphical abstract: Display Omitted Research highlights: > 6-bromoisovanillin induced spindle disruption and sustained mitotic arrest, consequently resulted in mitotic catastrophe. > Proteomic profiling identified 137 differentially expressed proteins associated mitotic catastrophe. > The 14-3-3-mediated signaling network was the most significantly enriched for the altered proteins. > The macromolecule complex assembly, cell cycle, chromatin remodeling and DNA repair, tubulin organization were also shown involved in mitotic catastrophe.« less

The Doctor Fox Research (1973) Rerevisited: "Educational Seduction" Ruled Out

ERIC Educational Resources Information Center

Peer, Eyal; Babad, Elisha

2014-01-01

In their study about the Dr. Fox lecture, Naftulin, Ware, and Donnelly (1973) claimed that an expressive speaker who delivered an attractive lecture devoid of any content could seduce students into believing that they had learned something significant. Over the decades, the study has been (and still is) cited hundreds of times and used by…

Influence of resistance breeding in common bean on rhizosphere microbiome composition and function.

PubMed

Mendes, Lucas William; Raaijmakers, Jos M; de Hollander, Mattias; Mendes, Rodrigo; Tsai, Siu Mui

2018-01-01

The rhizosphere microbiome has a key role in plant growth and health, providing a first line of defense against root infections by soil-borne pathogens. Here, we investigated the composition and metabolic potential of the rhizobacterial community of different common bean (Phaseolus vulgaris) cultivars with variable levels of resistance to the fungal root pathogen Fusarium oxysporum (Fox). For the different bean cultivars grown in two soils with contrasting physicochemical properties and microbial diversity, rhizobacterial abundance was positively correlated with Fox resistance. Pseudomonadaceae, bacillaceae, solibacteraceae and cytophagaceae were more abundant in the rhizosphere of the Fox-resistant cultivar. Network analyses showed a modular topology of the rhizosphere microbiome of the Fox-resistant cultivar, suggesting a more complex and highly connected bacterial community than in the rhizosphere of the Fox-susceptible cultivar. Metagenome analyses further revealed that specific functional traits such as protein secretion systems and biosynthesis genes of antifungal phenazines and rhamnolipids were more abundant in the rhizobacterial community of the Fox-resistant cultivar. Our findings suggest that breeding for Fox resistance in common bean may have co-selected for other unknown plant traits that support a higher abundance of specific beneficial bacterial families in the rhizosphere with functional traits that reinforce the first line of defense.

Molecular cloning, expression and molecular modeling of chemosensory protein from Spodoptera litura and its binding properties with Rhodojaponin III.

PubMed

Zhang, Yanbo; Dong, Xiaolin; Liu, Jinxiang; Hu, Meiying; Zhong, Guohua; Geng, Peng; Yi, Xin

2012-01-01

Insects stimulate specific behaviors by the correct recognition of the chemicals in the external environment. Rhodojaponin III is a botanical grayanoid diterpenid oviposition deterrent isolated from Rhododendron molle. In this study we aimed to determine whether the CSPs involved in the recognition of Rhodojaponin III. A full-length cDNA encoding chemosensory protein was isolated from the antennae of Spodoptera litura Fabricius (CSPSlit, GenBank Accession No. DQ007458). The full-length cDNA of NlFoxA is 1789 bp and has an open reading frame (ORF) of 473 bp, encoding a protein of 126 amino acids, Northern blot analysis revealed that CSPSlit mRNA was mainly expressed in the antennae, legs, wings and female abdomens. A three-dimensional model of CSPSlit was constructed using homology modeling method, and its reliability was evaluated. The active site of CSPSlit was calculated using CDOCKER program indicated that the Tyr24, Ile45, Leu49, Thr64, Leu68, Trp79 and Leu82 were responsible ligand-binding active site on identifying Rhodojaponin III in the CSPSlit. The recombinant CSPSlit protein was expressed in Escherichia coli and purified using single-step Ni-NTA affinity chromatography. Fluorescence emission spectra revealed that the CSPSlit protein had significant affinity to rhodojaponin III. These results mean that CSPSlit is critical for insects identify the Rhodojaponin III.

Molecular Cloning, Expression and Molecular Modeling of Chemosensory Protein from Spodoptera litura and Its Binding Properties with Rhodojaponin III

PubMed Central

Zhang, Yanbo; Dong, Xiaolin; Liu, Jinxiang; Hu, Meiying; Zhong, Guohua; Geng, Peng; Yi, Xin

2012-01-01

Insects stimulate specific behaviors by the correct recognition of the chemicals in the external environment. Rhodojaponin III is a botanical grayanoid diterpenid oviposition deterrent isolated from Rhododendron molle. In this study we aimed to determine whether the CSPs involved in the recognition of Rhodojaponin III. A full-length cDNA encoding chemosensory protein was isolated from the antennae of Spodoptera litura Fabricius (CSPSlit, GenBank Accession No. DQ007458). The full-length cDNA of NlFoxA is 1789 bp and has an open reading frame (ORF) of 473 bp, encoding a protein of 126 amino acids, Northern blot analysis revealed that CSPSlit mRNA was mainly expressed in the antennae, legs, wings and female abdomens. A three-dimensional model of CSPSlit was constructed using homology modeling method, and its reliability was evaluated. The active site of CSPSlit was calculated using CDOCKER program indicated that the Tyr24, Ile45, Leu49, Thr64, Leu68, Trp79 and Leu82 were responsible ligand-binding active site on identifying Rhodojaponin III in the CSPSlit. The recombinant CSPSlit protein was expressed in Escherichia coli and purified using single-step Ni-NTA affinity chromatography. Fluorescence emission spectra revealed that the CSPSlit protein had significant affinity to rhodojaponin III. These results mean that CSPSlit is critical for insects identify the Rhodojaponin III. PMID:23133516

daf-16/FoxO promotes gluconeogenesis and trehalose synthesis during starvation to support survival.

PubMed

Hibshman, Jonathan D; Doan, Alexander E; Moore, Brad T; Kaplan, Rebecca Ew; Hung, Anthony; Webster, Amy K; Bhatt, Dhaval P; Chitrakar, Rojin; Hirschey, Matthew D; Baugh, L Ryan

2017-10-24

daf-16 /FoxO is required to survive starvation in Caenorhabditis elegans , but how daf-16I FoxO promotes starvation resistance is unclear. We show that daf-16 /FoxO restructures carbohydrate metabolism by driving carbon flux through the glyoxylate shunt and gluconeogenesis and into synthesis of trehalose, a disaccharide of glucose. Trehalose is a well-known stress protectant, capable of preserving membrane organization and protein structure during abiotic stress. Metabolomic, genetic, and pharmacological analyses confirm increased trehalose synthesis and further show that trehalose not only supports survival as a stress protectant but also serves as a glycolytic input. Furthermore, we provide evidence that metabolic cycling between trehalose and glucose is necessary for this dual function of trehalose. This work demonstrates that daf-16 /FoxO promotes starvation resistance by shifting carbon metabolism to drive trehalose synthesis, which in turn supports survival by providing an energy source and acting as a stress protectant.

Sociability and synapse subtype-specific defects in mice lacking SRPX2, a language-associated gene

PubMed Central

Cong, Qifei; Palmer, Christian R.

2018-01-01

The FoxP2 transcription factor and its target genes have been implicated in developmental brain diseases with a prominent language component, such as developmental verbal dyspraxia and specific language impairment. How FoxP2 affects neural circuitry development remains poorly understood. The sushi domain protein SRPX2 is a target of FoxP2, and mutations in SRPX2 are associated with language defects in humans. We have previously shown that SRPX2 is a synaptogenic protein that increases excitatory synapse density. Here we provide the first characterization of mice lacking the SRPX2 gene, and show that these mice exhibit defects in both neural circuitry and communication and social behaviors. Specifically, we show that mice lacking SRPX2 show a specific reduction in excitatory VGlut2 synapses in the cerebral cortex, while VGlut1 and inhibitory synapses were largely unaffected. SRPX2 KO mice also exhibit an abnormal ultrasonic vocalization ontogenetic profile in neonatal pups, and reduced preference for social novelty. These data demonstrate a functional role for SRPX2 during brain development, and further implicate FoxP2 and its targets in regulating the development of vocalization and social circuits. PMID:29920554

Forkhead box transcription factors in embryonic heart development and congenital heart disease.

PubMed

Zhu, Hong

2016-01-01

Embryonic heart development is a very complicated process regulated precisely by a network composed of many genes and signaling pathways in time and space. Forkhead box (Fox, FOX) proteins are a family of transcription factors characterized by the presence of an evolutionary conserved "forkhead"or "winged-helix" DNA-binding domain and able to organize temporal and spatial gene expression during development. They are involved in a wide variety of cellular processes, such as cell cycle progression, proliferation, differentiation, migration, metabolism and DNA damage response. An abundance of studies in model organisms and systems has established that Foxa2, Foxc1/c2, Foxh1 and Foxm1, Foxos and Foxps are important components of the signaling pathways that instruct cardiogenesis and embryonic heart development, playing paramount roles in heart development. The previous studies also have demonstrated that mutations in some of the forkhead box genes and the aberrant expression of forkhead box gene are heavily implicated in the congenital heart disease (CHD) of humans. This review primarily focuses on the current understanding of heart development regulated by forkhead box transcription factors and molecular genetic mechanisms by which forkhead box factors modulate heart development during embryogenesis and organogenesis. This review also summarizes human CHD related mutations in forkhead box genes as well as the abnormal expression of forkhead box gene, and discusses additional possible regulatory mechanisms of the forkhead box genes during embryonic heart development that warrant further investigation. Copyright © 2015 Elsevier Inc. All rights reserved.

PreImplantation Factor in endometriosis: A potential role in inducing immune privilege for ectopic endometrium

PubMed Central

Scarpellini, Fabio; Marconi, Daniela; Rossi, Gabriele; Simmilion, Cedric; Mueller, Michael D.; Barnea, Eytan R.

2017-01-01

Endometriosis is a chronic inflammatory condition characterised by the growth of endometrial epithelial and stromal cells outside the uterine cavity. In addition to Sampson’s theory of retrograde menstruation, endometriosis pathogenesis is facilitated by a privileged inflammatory microenvironment, with T regulatory FoxP3+ expressing T cells (Tregs) being a significant factor. PreImplantation Factor (PIF) is a peptide essential for pregnancy recognition and development. An immune modulatory function of the synthetic PIF analog (sPIF) has been successfully confirmed in multiple animal models. We report that PIF is expressed in the epithelial ectopic cells in close proximity to FoxP3+ stromal cells. We provide evidence that PIF interacts with FoxP3+ cells and modulates cell viability, dependent on cell source and presence of inflammatory mediators. Our finding represent a novel PIF-based mechanism in endometriosis that has potential for novel therapeutics. PMID:28902871

Activation of PPAR alpha by fenofibrate inhibits apoptosis in vascular adventitial fibroblasts partly through SIRT1-mediated deacetylation of FoxO1.

PubMed

Wang, Wei-Rong; Liu, En-Qi; Zhang, Ji-Ye; Li, Yan-Xiang; Yang, Xiao-Feng; He, Yan-Hao; Zhang, Wei; Jing, Ting; Lin, Rong

2015-10-15

Recent studies demonstrated that the ligand-activated transcription factor peroxisome proliferator-activated receptorα (PPARα) acts in association with histone deacetylase sirtuin 1 (SIRT1) in the regulation of metabolism and inflammation involved in cardiovascular diseases. PPARα activation also participates in the modulation of cell apoptosis. Our previous study found that SIRT1 inhibits the apoptosis of vascular adventitial fibroblasts (VAFs). However, whether the role of PPARα in apoptosis of VAFs is mediated by SIRT1 remains unknown. In this study, we aimed to determine the effect of PPARα agonist fenofibrate on cell apoptosis and SIRT1 expression and related mechanisms in ApoE(-/-) mice and VAFs in vitro. We found that fenofibrate inhibited cell apoptosis in vascular adventitia and up-regulated SIRT1 expression in aorta of ApoE(-/-) mice. Moreover, SIRT1 activator resveratrol (RSV) further enhanced these effects of fenofibrate. In vitro study showed that activation of PPARα by fenofibrate inhibited TNF-α-induced cell apoptosis and cell cycle arrest in VAFs. Meanwhile, fenofibrate up-regulated SIRT1 expression and inhibited SIRT1 translocation from nucleus to cytoplasm in VAFs stimulated with TNF-α. Moreover, the effects of fenofibrate on cell apoptosis and SIRT1 expression in VAFs were reversed by PPARα antagonist GW6471. Importantly, treatment of VAFs with SIRT1 siRNA or pcDNA3.1(+)-SIRT1 showed that the inhibitory effect of fenofibrate on cell apoptosis in VAFs through SIRT1. On the other hand, knockdown of FoxO1 decreased cell apoptosis of VAFs compared with fenofibrate group. Overexpression of FoxO1 increased cell apoptosis of VAFs compared with fenofibrate group. Further study found that fenofibrate decreased the expression of acetylated-FoxO1 in TNF-α-stimulated VAFs, which was abolished by SIRT1 knockdown. Taken together, these findings indicate that activation of PPARα by fenofibrate inhibits cell apoptosis in VAFs partly through the SIRT1-mediated deacetylation of FoxO1. Copyright © 2015 Elsevier Inc. All rights reserved.

Hox repertoires for motor neuron diversity and connectivity gated by a single accessory factor, FoxP1.

PubMed

Dasen, Jeremy S; De Camilli, Alessandro; Wang, Bin; Tucker, Philip W; Jessell, Thomas M

2008-07-25

The precision with which motor neurons innervate target muscles depends on a regulatory network of Hox transcription factors that translates neuronal identity into patterns of connectivity. We show that a single transcription factor, FoxP1, coordinates motor neuron subtype identity and connectivity through its activity as a Hox accessory factor. FoxP1 is expressed in Hox-sensitive motor columns and acts as a dose-dependent determinant of columnar fate. Inactivation of Foxp1 abolishes the output of the motor neuron Hox network, reverting the spinal motor system to an ancestral state. The loss of FoxP1 also changes the pattern of motor neuron connectivity, and in the limb motor axons appear to select their trajectories and muscle targets at random. Our findings show that FoxP1 is a crucial determinant of motor neuron diversification and connectivity, and clarify how this Hox regulatory network controls the formation of a topographic neural map.

FoxO is a critical regulator of stem cell maintenance in immortal Hydra.

PubMed

Boehm, Anna-Marei; Khalturin, Konstantin; Anton-Erxleben, Friederike; Hemmrich, Georg; Klostermeier, Ulrich C; Lopez-Quintero, Javier A; Oberg, Hans-Heinrich; Puchert, Malte; Rosenstiel, Philip; Wittlieb, Jörg; Bosch, Thomas C G

2012-11-27

Hydra's unlimited life span has long attracted attention from natural scientists. The reason for that phenomenon is the indefinite self-renewal capacity of its stem cells. The underlying molecular mechanisms have yet to be explored. Here, by comparing the transcriptomes of Hydra's stem cells followed by functional analysis using transgenic polyps, we identified the transcription factor forkhead box O (FoxO) as one of the critical drivers of this continuous self-renewal. foxO overexpression increased interstitial stem cell and progenitor cell proliferation and activated stem cell genes in terminally differentiated somatic cells. foxO down-regulation led to an increase in the number of terminally differentiated cells, resulting in a drastically reduced population growth rate. In addition, it caused down-regulation of stem cell genes and antimicrobial peptide (AMP) expression. These findings contribute to a molecular understanding of Hydra's immortality, indicate an evolutionarily conserved role of FoxO in controlling longevity from Hydra to humans, and have implications for understanding cellular aging.

Sequence analysis of the Ras-MAPK pathway genes SOS1, EGFR & GRB2 in silver foxes (Vulpes vulpes): candidate genes for hereditary hyperplastic gingivitis.

PubMed

Clark, Jo-Anna B J; Tully, Sara J; Dawn Marshall, H

2014-12-01

Hereditary hyperplastic gingivitis (HHG) is an autosomal recessive disease that presents with progressive gingival proliferation in farmed silver foxes. Hereditary gingival fibromatosis (HGF) is an analogous condition in humans that is genetically heterogeneous with several known autosomal dominant loci. For one locus the causative mutation is in the Son of sevenless homologue 1 (SOS1) gene. For the remaining loci, the molecular mechanisms are unknown but Ras pathway involvement is suspected. Here we compare sequences for the SOS1 gene, and two adjacent genes in the Ras pathway, growth receptor bound protein 2 (GRB2) and epidermal growth factor receptor (EGFR), between HHG-affected and unaffected foxes. We conclude that the known HGF causative mutation does not cause HHG in foxes, nor do the coding regions or intron-exon boundaries of these three genes contain any candidate mutations for fox gum disease. Patterns of molecular evolution among foxes and other mammals reflect high conservation and strong functional constraints for SOS1 and GRB2 but reveal a lineage-specific pattern of variability in EGFR consistent with mutational rate differences, relaxed functional constraints, and possibly positive selection.

Stem cell-dependent formation of a functional anterior regeneration pole in planarians requires Zic and Forkhead transcription factors.

PubMed

Vogg, Matthias C; Owlarn, Suthira; Pérez Rico, Yuvia A; Xie, Jianlei; Suzuki, Yoko; Gentile, Luca; Wu, Wei; Bartscherer, Kerstin

2014-06-15

Planarians can regenerate their head within days. This process depends on the direction of adult stem cells to wound sites and the orchestration of their progenitors to commit to appropriate lineages and to arrange into patterned tissues. We identified a zinc finger transcription factor, Smed-ZicA, as a downstream target of Smed-FoxD, a Forkhead transcription factor required for head regeneration. Smed-zicA and Smed-FoxD are co-expressed with the Wnt inhibitor notum and the Activin inhibitor follistatin in a cluster of cells at the anterior-most tip of the regenerating head - the anterior regeneration pole - and in surrounding stem cell progeny. Depletion of Smed-zicA and Smed-FoxD by RNAi abolishes notum and follistatin expression at the pole and inhibits head formation downstream of initial polarity decisions. We suggest a model in which ZicA and FoxD transcription factors synergize to control the formation of Notum- and Follistatin-producing anterior pole cells. Pole formation might constitute an early step in regeneration, resulting in a signaling center that orchestrates cellular events in the growing tissue. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

A Fox2-Dependent Fatty Acid ß-Oxidation Pathway Coexists Both in Peroxisomes and Mitochondria of the Ascomycete Yeast Candida lusitaniae

PubMed Central

Bessoule, Jean-Jacques; Salin, Bénédicte; Lucas-Guérin, Marine; Manon, Stephen; Dementhon, Karine; Noël, Thierry

2014-01-01

It is generally admitted that the ascomycete yeasts of the subphylum Saccharomycotina possess a single fatty acid ß-oxidation pathway located exclusively in peroxisomes, and that they lost mitochondrial ß-oxidation early during evolution. In this work, we showed that mutants of the opportunistic pathogenic yeast Candida lusitaniae which lack the multifunctional enzyme Fox2p, a key enzyme of the ß-oxidation pathway, were still able to grow on fatty acids as the sole carbon source, suggesting that C. lusitaniae harbored an alternative pathway for fatty acid catabolism. By assaying 14Cα-palmitoyl-CoA consumption, we demonstrated that fatty acid catabolism takes place in both peroxisomal and mitochondrial subcellular fractions. We then observed that a fox2Δ null mutant was unable to catabolize fatty acids in the mitochondrial fraction, thus indicating that the mitochondrial pathway was Fox2p-dependent. This finding was confirmed by the immunodetection of Fox2p in protein extracts obtained from purified peroxisomal and mitochondrial fractions. Finally, immunoelectron microscopy provided evidence that Fox2p was localized in both peroxisomes and mitochondria. This work constitutes the first demonstration of the existence of a Fox2p-dependent mitochondrial β-oxidation pathway in an ascomycetous yeast, C. lusitaniae. It also points to the existence of an alternative fatty acid catabolism pathway, probably located in peroxisomes, and functioning in a Fox2p-independent manner. PMID:25486052

A Fox2-dependent fatty acid ß-oxidation pathway coexists both in peroxisomes and mitochondria of the ascomycete yeast Candida lusitaniae.

PubMed

Gabriel, Frédéric; Accoceberry, Isabelle; Bessoule, Jean-Jacques; Salin, Bénédicte; Lucas-Guérin, Marine; Manon, Stephen; Dementhon, Karine; Noël, Thierry

2014-01-01

It is generally admitted that the ascomycete yeasts of the subphylum Saccharomycotina possess a single fatty acid ß-oxidation pathway located exclusively in peroxisomes, and that they lost mitochondrial ß-oxidation early during evolution. In this work, we showed that mutants of the opportunistic pathogenic yeast Candida lusitaniae which lack the multifunctional enzyme Fox2p, a key enzyme of the ß-oxidation pathway, were still able to grow on fatty acids as the sole carbon source, suggesting that C. lusitaniae harbored an alternative pathway for fatty acid catabolism. By assaying 14Cα-palmitoyl-CoA consumption, we demonstrated that fatty acid catabolism takes place in both peroxisomal and mitochondrial subcellular fractions. We then observed that a fox2Δ null mutant was unable to catabolize fatty acids in the mitochondrial fraction, thus indicating that the mitochondrial pathway was Fox2p-dependent. This finding was confirmed by the immunodetection of Fox2p in protein extracts obtained from purified peroxisomal and mitochondrial fractions. Finally, immunoelectron microscopy provided evidence that Fox2p was localized in both peroxisomes and mitochondria. This work constitutes the first demonstration of the existence of a Fox2p-dependent mitochondrial β-oxidation pathway in an ascomycetous yeast, C. lusitaniae. It also points to the existence of an alternative fatty acid catabolism pathway, probably located in peroxisomes, and functioning in a Fox2p-independent manner.

FoxO4 inhibits atherosclerosis through its function in bone marrow derived cells

PubMed Central

Zhu, Min; Zhang, Qing-Jun; Wang, Lin; Li, Hao; Liu, Zhi-Ping

2011-01-01

Objectives FoxO proteins are transcription factors involved in varieties of cellular processes, including immune cell homeostasis, cytokine production, anti-oxidative stress, and cell proliferation and differentiation. Although these processes are implicated in the development of atherosclerosis, very little is known about the role of FoxO proteins in the context of atherosclerosis. Our objectives were to determine whether and how inactivation of Foxo4, a member of the FoxO family, in vivo promotes atherosclerosis. Methods and Results Apolipoprotein E-deficient (apoE−/−) mice were crossbred with animals lacking Foxo4 (Foxo4−/−). After 10 weeks on a high fat diet (HFD), Foxo4−/−apoE−/− mice showed elevated atherosclerosis and increased amount of macrophages and T cells in the plaque compared to apoE−/− mice. Bone marrow transplantations of chimeric C57B/6 mice reconstituted with either wild-type or Foxo4−/− bone marrows indicate that Foxo4-deficiency in bone marrow derived cells sufficiently promoted atherosclerosis. Foxo4-null macrophages produced elevated inflammatory cytokine IL-6 and levels of reactive oxygen species (ROS) in response to lipopolysaccharides in vitro. Serum levels of IL-6 were upregulated in HFD-fed Foxo4−/−apoE−/− mice compared to those of apoE−/− mice. Conclusions FoxO4 inhibits atherosclerosis through bone marrow derived cells, possibly by inhibition of ROS and inflammatory cytokines that promote monocyte recruitment and/or retention. PMID:22005198

En1 directs superior olivary complex neuron positioning, survival, and expression of FoxP1.

PubMed

Altieri, Stefanie C; Jalabi, Walid; Zhao, Tianna; Romito-DiGiacomo, Rita R; Maricich, Stephen M

2015-12-01

Little is known about the genetic pathways and transcription factors that control development and maturation of central auditory neurons. En1, a gene expressed by a subset of developing and mature superior olivary complex (SOC) cells, encodes a homeodomain transcription factor important for neuronal development in the midbrain, cerebellum, hindbrain and spinal cord. Using genetic fate-mapping techniques, we show that all En1-lineal cells in the SOC are neurons and that these neurons are glycinergic, cholinergic and GABAergic in neurotransmitter phenotype. En1 deletion does not interfere with specification or neural fate of these cells, but does cause aberrant positioning and subsequent death of all En1-lineal SOC neurons by early postnatal ages. En1-null cells also fail to express the transcription factor FoxP1, suggesting that FoxP1 lies downstream of En1. Our data define important roles for En1 in the development and maturation of a diverse group of brainstem auditory neurons. Copyright © 2015 Elsevier Inc. All rights reserved.

Exogenous FABP4 increases breast cancer cell proliferation and activates the expression of fatty acid transport proteins.

PubMed

Guaita-Esteruelas, Sandra; Bosquet, Alba; Saavedra, Paula; Gumà, Josep; Girona, Josefa; Lam, Eric W-F; Amillano, Kepa; Borràs, Joan; Masana, Lluís

2017-01-01

Adipose tissue plays an important role in tumor progression, because it provides nutrients and adipokines to proliferating cells. Fatty acid binding protein 4 (FABP4) is a key adipokine for fatty acid transport. In metabolic pathologies, plasma levels of FABP4 are increased. However, the role of this circulating protein is unknown. Recent studies have demonstrated that FABP4 might have a role in tumor progression, but the molecular mechanisms involved are still unclear. In this study, we analysed the role of eFABP4 (exogenous FABP4) in breast cancer progression. MCF-7 and MDA-MB-231 breast cancer cells did not express substantial levels of FABP4 protein, but intracellular FABP4 levels increased after eFABP4 incubation. Moreover, eFABP4 enhanced the proliferation of these breast cancer cells but did not have any effect on MCF-7 and MDA-MB-231 cell migration. Additionally, eFABP4 induced the AKT and MAPK signaling cascades in breast cancer cells, and the inhibition of these pathways reduced the eFBAP4-mediated cell proliferation. Interestingly, eFABP4 treatment in MCF-7 cells increased levels of the transcription factor FoxM1 and the fatty acid transport proteins CD36 and FABP5. In summary, we showed that eFABP4 plays a key role in tumor proliferation and activates the expression of fatty acid transport proteins in MCF-7 breast cancer cells. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

The complete mitochondrial genome sequence of the Tibetan red fox (Vulpes vulpes montana).

PubMed

Zhang, Jin; Zhang, Honghai; Zhao, Chao; Chen, Lei; Sha, Weilai; Liu, Guangshuai

2015-01-01

In this study, the complete mitochondrial genome of the Tibetan red fox (Vulpes Vulpes montana) was sequenced for the first time using blood samples obtained from a wild female red fox captured from Lhasa in Tibet, China. Qinghai--Tibet Plateau is the highest plateau in the world with an average elevation above 3500 m. Sequence analysis showed it contains 12S rRNA gene, 16S rRNA gene, 22 tRNA genes, 13 protein-coding genes and 1 control region (CR). The variable tandem repeats in CR is the main reason of the length variability of mitochondrial genome among canide animals.

Chemotherapy triggers HIF-1–dependent glutathione synthesis and copper chelation that induces the breast cancer stem cell phenotype

PubMed Central

Lu, Haiquan; Samanta, Debangshu; Xiang, Lisha; Zhang, Huimin; Hu, Hongxia; Chen, Ivan; Bullen, John W.; Semenza, Gregg L.

2015-01-01

Triple negative breast cancer (TNBC) accounts for 10–15% of all breast cancer but is responsible for a disproportionate share of morbidity and mortality because of its aggressive characteristics and lack of targeted therapies. Chemotherapy induces enrichment of breast cancer stem cells (BCSCs), which are responsible for tumor recurrence and metastasis. Here, we demonstrate that chemotherapy induces the expression of the cystine transporter xCT and the regulatory subunit of glutamate-cysteine ligase (GCLM) in a hypoxia-inducible factor (HIF)-1–dependent manner, leading to increased intracellular glutathione levels, which inhibit mitogen-activated protein kinase kinase (MEK) activity through copper chelation. Loss of MEK-ERK signaling causes FoxO3 nuclear translocation and transcriptional activation of the gene encoding the pluripotency factor Nanog, which is required for enrichment of BCSCs. Inhibition of xCT, GCLM, FoxO3, or Nanog blocks chemotherapy-induced enrichment of BCSCs and impairs tumor initiation. These results suggest that, in combination with chemotherapy, targeting BCSCs by inhibiting HIF-1–regulated glutathione synthesis may improve outcome in TNBC. PMID:26229077

Drosophila FoxP Mutants Are Deficient in Operant Self-Learning

PubMed Central

Mendoza, Ezequiel; Colomb, Julien; Rybak, Jürgen; Pflüger, Hans-Joachim; Zars, Troy

2014-01-01

Intact function of the Forkhead Box P2 (FOXP2) gene is necessary for normal development of speech and language. This important role has recently been extended, first to other forms of vocal learning in animals and then also to other forms of motor learning. The homology in structure and in function among the FoxP gene members raises the possibility that the ancestral FoxP gene may have evolved as a crucial component of the neural circuitry mediating motor learning. Here we report that genetic manipulations of the single Drosophila orthologue, dFoxP, disrupt operant self-learning, a form of motor learning sharing several conceptually analogous features with language acquisition. Structural alterations of the dFoxP locus uncovered the role of dFoxP in operant self-learning and habit formation, as well as the dispensability of dFoxP for operant world-learning, in which no motor learning occurs. These manipulations also led to subtle alterations in the brain anatomy, including a reduced volume of the optic glomeruli. RNAi-mediated interference with dFoxP expression levels copied the behavioral phenotype of the mutant flies, even in the absence of mRNA degradation. Our results provide evidence that motor learning and language acquisition share a common ancestral trait still present in extant invertebrates, manifest in operant self-learning. This ‘deep’ homology probably traces back to before the split between vertebrate and invertebrate animals. PMID:24964149

Forkhead Box O1 Regulates Macrophage Polarization Following Staphylococcus aureus Infection: Experimental Murine Data and Review of the Literature.

PubMed

Wang, Yu-Chen; Ma, Hong-Di; Yin, Xue-Ying; Wang, Yin-Hu; Liu, Qing-Zhi; Yang, Jing-Bo; Shi, Qing-Hua; Sun, Baolin; Gershwin, M Eric; Lian, Zhe-Xiong

2016-12-01

The functions of macrophages that lead to effective host responses are critical for protection against Staphylococcus aureus. Deep tissue-invading S. aureus initially countered by macrophages trigger macrophage accumulation and induce inflammatory responses through surface receptors, especially toll-like receptor 2 (TLR2). Here, we found that macrophages formed sporadic aggregates in the liver during infection. Within those aggregates, macrophages co-localized with T cells and were indispensable for their infiltration. In addition, we have focused on the mechanisms underlying the polarization of macrophages in Forkhead box transcription factor O1 (FoxO1) conditional knockout Lys Cre/+ FoxO1 fl/fl mice following S. aureus infection and report herein that macrophage M1-M2 polarization via TLR2 is intrinsically regulated by FoxO1. Indeed, for effective FoxO1 activity, stimulation of TLR2 is essential. However, following S. aureus challenge, there was a decrease in macrophage FoxO1, with increased phosphorylation of FoxO1 because of TLR2-mediated activation of PI3K/Akt and c-Raf/MEK/ERK pathway. Following infection in Lys Cre/+ FoxO1 fl/fl mice, mice became more susceptible to S. aureus with reduced macrophage aggregation in the liver and attenuated Th1 and Th17 responses. FoxO1 abrogation reduced M1 pro-inflammatory responses triggered by S. aureus and enhanced M2 polarization in macrophages. In contrast, overexpression of FoxO1 in macrophages increased pro-inflammatory mediators and functional surface molecule expression. In conclusion, macrophage FoxO1 is critical to promote M1 polarization and maintain a competent T cell immune response against S. aureus infection in the liver. FoxO1 regulates macrophage M1-M2 polarization downstream of TLR2 dynamically through phosphorylation.

The Atypical Antipsychotic Agent, Clozapine, Protects Against Corticosterone-Induced Death of PC12 Cells by Regulating the Akt/FoxO3a Signaling Pathway.

PubMed

Zeng, Zhiwen; Wang, Xue; Bhardwaj, Sanjeev K; Zhou, Xuanhe; Little, Peter J; Quirion, Remi; Srivastava, Lalit K; Zheng, Wenhua

2017-07-01

Schizophrenia is one of the most severe psychiatric disorders. Increasing evidence implicates that neurodegeneration is a component of schizophrenia pathology and some atypical antipsychotics are neuroprotective and successful in slowing the progressive morphological brain changes. As an antipsychotic agent, clozapine has superior and unique effects, but the intracellular signaling pathways that mediate clozapine action remain to be elucidated. The phosphatidylinositol-3-kinase/protein kinase B/Forkhead box O3 (PI3K/Akt/FoxO3a) pathway is crucial for neuronal survival. However, little information is available regarding this pathway with clozapine. In the present study, we investigated the protective effect of clozapine on the PC12 cells against corticosterone toxicity. Our results showed that corticosterone decreases the phosphorylation of Akt and FoxO3a, leading to the nuclear localization of FoxO3a and the apoptosis of PC12 cells, while clozapine concentration dependently protected PC12 cells against corticosterone insult. Pathway inhibitors studies displayed that the protective effect of clozapine was reversed by LY294002 and wortmannin, two PI3K inhibitors, or Akt inhibitor VIII although several other inhibitors had no effect. The shRNA knockdown results displayed that downregulated Akt1 or FoxO3a attenuated the protective effect of clozapine. Western blot analyses revealed that clozapine induced the phosphorylation of Akt and FoxO3a by the PI3K/Akt pathway and reversed the reduction of the phosphorylated Akt and FoxO3a and the nuclear translocation of FoxO3a evoked by corticosterone. Together, our data indicates that clozapine protects PC12 cells against corticosterone-induced cell death by modulating activity of the PI3K/Akt/FoxO3a pathway.

Association of Regulatory T Cells with Diabetes Type-1 and Its Renal and Vascular Complications Based on the Expression of Forkhead Box Protein P3 (FoxP3), Helios and Neurophilin-1.

PubMed

Khamechian, Tahereh; Irandoust, Behnaz; Mohammadi, Hanieh; Nikoueinejad, Hassan; Akbari, Hossein

2018-04-01

In recent years, it has been recognized that regulatory T cells (Tregs) play a critical role in maintaining immune tolerance. Moreover, the expression of two markers named Helios and neurophilin-1 (NRP-1) has been highlighted in such cells. Helios, an intracellular transcription marker, largely differentiates twomost operative sub group of Tregs, namely naturally occurring (nTreg) and induced (iTreg) Tregs, and NRP-1 is reckoned as a membranous activity marker of Tregs. We aimed to count peripheral mononuclear cells expressing such markers in a group of type 1 diabetes patients to elucidate the possible role of Tregs in the pathogenesis of such disease and its complications. Blood samples from 61 adult patients with type 1 diabetes and 61 sex and age-matched healthy controls were tested to count two types of Tregs, namely naturally occurring and inducible types, according to the expression of cell surface markers of CD4/CD25/CD47-FITC/PE/APC and intracellular markers of FoxP3/Helios-PE-CY5/eFlour450 by flow cytometry, respectively.We also investigated the relation between expression of such markers with HbA1c, urine albumin/creatinine ratio (UACR), and common carotid intima thickness (CIMT). The circulatory frequency of both Helios+ and Helios- T-cells were significantly decreased in patients compared to those in healthy controls (p<0.001). There was also a significant decrease in circulatory frequency of Helios+ NRP-1+ and Helios- NRP-1+ cells in the patients compared to controls (p=0.029). According to expression of Helios and NRP-1 markers, the number and function of both Tregs were decreased in diabetic patients. Moreover, the neurophilin expression was inversely associated with complications of type 1 diabetes.

An Integrated Proteomics and Bioinformatics Approach Reveals the Anti-inflammatory Mechanism of Carnosic Acid

PubMed Central

Wang, Li-Chao; Wei, Wen-Hui; Zhang, Xiao-Wen; Liu, Dan; Zeng, Ke-Wu; Tu, Peng-Fei

2018-01-01

Drastic macrophages activation triggered by exogenous infection or endogenous stresses is thought to be implicated in the pathogenesis of various inflammatory diseases. Carnosic acid (CA), a natural phenolic diterpene extracted from Salvia officinalis plant, has been reported to possess anti-inflammatory activity. However, its role in macrophages activation as well as potential molecular mechanism is largely unexplored. In the current study, we sought to elucidate the anti-inflammatory property of CA using an integrated approach based on unbiased proteomics and bioinformatics analysis. CA significantly inhibited the robust increase of nitric oxide and TNF-α, downregulated COX2 protein expression, and lowered the transcriptional level of inflammatory genes including Nos2, Tnfα, Cox2, and Mcp1 in LPS-stimulated RAW264.7 cells, a murine model of peritoneal macrophage cell line. The LC-MS/MS-based shotgun proteomics analysis showed CA negatively regulated 217 LPS-elicited proteins which were involved in multiple inflammatory processes including MAPK, nuclear factor (NF)-κB, and FoxO signaling pathways. A further molecular biology analysis revealed that CA effectually inactivated IKKβ/IκB-α/NF-κB, ERK/JNK/p38 MAPKs, and FoxO1/3 signaling pathways. Collectively, our findings demonstrated the role of CA in regulating inflammation response and provide some insights into the proteomics-guided pharmacological mechanism study of natural products. PMID:29713284

Intrinsic role of FoxO3a in the development of CD8+ T cell memory

PubMed Central

Tzelepis, Fanny; Joseph, Julie; Haddad, Elias K.; MacLean, Susanne; Dudani, Renu; Agenes, Fabien; Peng, Stanford L.; Sekaly, Rafick-Pierre; Sad, Subash

2013-01-01

CD8+ T cells undergo rapid expansion during infection with intracellular pathogens, which is followed by swift and massive culling of primed CD8+ T cells. The mechanisms that govern the massive contraction and maintenance of primed CD8+ T cells are not clear. We show here that the transcription factor, FoxO3a does not influence antigen-presentation and the consequent expansion of CD8+ T cell response during Listeria monocytogenes (LM) infection, but plays a key role in the maintenance of memory CD8+ T cells. The effector function of primed CD8+ T cells as revealed by cytokine secretion and CD107a degranulation was not influenced by inactivation of FoxO3a. Interestingly, FoxO3a-deficient CD8+ T cells displayed reduced expression of pro-apoptotic molecules BIM and PUMA during the various phases of response, and underwent reduced apoptosis in comparison to WT cells. A higher number of memory precursor effector cells (MPECs) and memory subsets were detectable in FoxO3a-deficient mice compared to WT mice. Furthermore, FoxO3a-deficient memory CD8+ T cells upon transfer into normal or RAG1-deficient mice displayed enhanced survival. These results suggest that FoxO3a acts in a cell intrinsic manner to regulate the survival of primed CD8+ T cells. PMID:23277488

The complete mitochondrial genome of the Tibetan fox (Vulpes ferrilata) and implications for the phylogeny of Canidae.

PubMed

Zhao, Chao; Zhang, Honghai; Liu, Guangshuai; Yang, Xiufeng; Zhang, Jin

2016-02-01

Canidae is a family of carnivores comprises about 36 extant species that have been defined as three distinct monophyletic groups based on multi-gene data sets. The Tibetan fox (Vulpes ferrilata) is a member of the family Canidae that is endemic to the Tibetan Plateau and has seldom been in the focus of phylogenetic analyses. To clarify the phylogenic relationship of V. ferrilata between other canids, we sequenced the mitochondrial genome and firstly attempted to clarify the relative phylogenetic position of V. ferrilata in canids using the complete mitochondrial genome data. The mitochondrial genome of the Tibetan fox was 16,667 bp, including 37 genes (13 protein-coding genes, 2 rRNA, and 22 tRNA) and a control region. A comparison analysis among the sequenced data of canids indicated that they shared a similar arrangement, codon usage, and other aspects. A phylogenetic analysis on the basis of the nearly complete mtDNA genomes of canids agreed with three monophyletic clades, and the Tibetan fox was highly supported as a sister group of the corsac fox within Vulpes. The estimation of the divergence time suggested a recent split between the Tibetan fox and the corsac fox and rapid evolution in canids. There was no genetic evidence for positive selection related to high-altitude adaption for the Tibetan fox in mtDNA and following studies should pay more attention to the detection of positive signals in nuclear genes involved in energy and oxygen metabolisms. Copyright © 2015 Académie des sciences. Published by Elsevier SAS. All rights reserved.

The differential effects of 2% oxygen preconditioning on the subsequent differentiation of mouse and human pluripotent stem cells.

PubMed

Fynes, Kate; Tostoes, Rui; Ruban, Ludmila; Weil, Ben; Mason, Christopher; Veraitch, Farlan S

2014-08-15

A major challenge facing the development of effective cell therapies is the efficient differentiation of pluripotent stem cells (PSCs) into pure populations. Lowering oxygen tension to physiological levels can affect both the expansion and differentiation stages. However, to date, there are no studies investigating the knock-on effect of culturing PSCs under low oxygen conditions on subsequent lineage commitment at ambient oxygen levels. PSCs were passaged three times at 2% O2 before allowing cells to spontaneously differentiate as embryoid bodies (EBs) in high oxygen (20% O2) conditions. Maintenance of mouse PSCs in low oxygen was associated with a significant increase in the expression of early differentiation markers FGF5 and Eomes, while conversely we observed decreased expression of these genes in human PSCs. Low oxygen preconditioning primed mouse PSCs for their subsequent differentiation into mesodermal and endodermal lineages, as confirmed by increased gene expression of Eomes, Goosecoid, Brachyury, AFP, Sox17, FoxA2, and protein expression of Brachyury, Eomes, Sox17, FoxA2, relative to high oxygen cultures. The effects extended to the subsequent formation of more mature mesodermal lineages. We observed significant upregulation of cardiomyocyte marker Nkx2.5, and critically a decrease in the number of contaminant pluripotent cells after 12 days using a directed cardiomyocyte protocol. However, the impact of low oxygen preconditioning was to prime human cells for ectodermal lineage commitment during subsequent EB differentiation, with significant upregulation of Nestin and β3-tubulin. Our research demonstrates the importance of oxygen tension control during cell maintenance on the subsequent differentiation of both mouse and human PSCs, and highlights the differential effects.

Lentivirus-mediated klotho up-regulation improves aging-related memory deficits and oxidative stress in senescence-accelerated mouse prone-8 mice.

PubMed

Zhou, Hong-Jing; Zeng, Chen-Ye; Yang, Ting-Ting; Long, Fang-Yi; Kuang, Xi; Du, Jun-Rong

2018-05-01

Oxidative stress caused by aging aggravates neuropathological changes and cognitive deficits. Klotho, an anti-aging protein, shows an anti-oxidative effect. The aims of the present study were to determine the potential therapeutic effect of klotho in aging-related neuropathological changes and memory impairments in senescence-accelerated mouse prone-8 (SAMP8) mice, and identify the potential mechanism of these neuroprotective effects. A lentivirus was used to deliver and sustain the expression of klotho. The lentiviral vectors were injected into the bilateral lateral ventricles of 7-month-old SAMP8 mice or age-matched SAMR1 mice. Three months later, the Y-maze alternation task and passive avoidance task were used to assess the memory deficits of the mice. In situ hybridization, immunohistochemistry, immunofluorescence, Nissl staining, quantitative real-time PCR and Western blot assays were applied in the following research. Our results showed that 3 months after injection of the lentiviral vectors encoding the full-length klotho gene, the expression of klotho in the brain was significantly increased in 10-month-old SAMP8 mice. This treatment reduced memory deficits, neuronal loss, synaptic damage and 4-HNE levels but increased mitochondrial manganese-superoxide dismutase (Mn-SOD) and catalase (CAT) expression. Moreover, the up-regulation of klotho expression decreased Akt and Forkhead box class O1 (FoxO1) phosphorylation. The present study provides a novel approach for klotho gene therapy and demonstrates that direct up-regulation of klotho in the brain might improve aging-related memory impairments and decrease oxidative stress. The underlying mechanism of this effect likely involves the inhibition of the Akt/FoxO1 pathway. Copyright © 2018 Elsevier Inc. All rights reserved.

Genetic and epigenetic mechanisms of gene regulation during lens development

PubMed Central

Cvekl, Ales; Duncan, Melinda K.

2007-01-01

Recent studies demonstrated a number of links between chromatin structure, gene expression, extracellular signaling and cellular differentiation during lens development. Lens progenitor cells originate from a pool of common progenitor cells, the pre-placodal region (PPR) which is formed due to a complex exchange of extracellular signals between the neural plate, naïve ectoderm and mesendoderm. A specific commitment to the lens program over alternate choices such as the formation of olfactory epithelium or the anterior pituitary is manifested by the formation of a thickened surface ectoderm, the lens placode. Mouse lens progenitor cells are characterized by the expression of a complement of lens lineage-specific transcription factors including Pax6, Six3 and Sox2, controlled by FGF and BMP signaling, followed later by c-Maf, Mab21like1, Prox1 and FoxE3. Proliferation of lens progenitors together with their morphogenetic movements results in the formation of the lens vesicle. This transient structure, comprised of lens precursor cells, is polarized with its anterior cells retaining their epithelial morphology and proliferative capacity, whereas the posterior lens precursor cells initiate terminal differentiation forming the primary lens fibers. Lens differentiation is marked by expression and accumulation of crystallins and other structural proteins. The transcriptional control of crystallin genes is characterized by the reiterative use of transcription factors required for the establishment of lens precursors in combination with more ubiquitously expressed factors (e.g. AP-1, AP-2α, CREB and USF) and recruitment of histone acetyltransferases (HATs) CBP and p300, and chromatin remodeling complexes SWI/SNF and ISWI. These studies have poised the study of lens development at the forefront of efforts to understand the connections between development, cell signaling, gene transcription and chromatin remodeling. PMID:17905638

Dual Regulation of Gluconeogenesis by Insulin and Glucose in the Proximal Tubules of the Kidney.

PubMed

Sasaki, Motohiro; Sasako, Takayoshi; Kubota, Naoto; Sakurai, Yoshitaka; Takamoto, Iseki; Kubota, Tetsuya; Inagi, Reiko; Seki, George; Goto, Moritaka; Ueki, Kohjiro; Nangaku, Masaomi; Jomori, Takahito; Kadowaki, Takashi

2017-09-01

Growing attention has been focused on the roles of the proximal tubules (PTs) of the kidney in glucose metabolism, including the mechanism of regulation of gluconeogenesis. In this study, we found that PT-specific insulin receptor substrate 1/2 double-knockout mice, established by using the newly generated sodium-glucose cotransporter 2 (SGLT2)-Cre transgenic mice, exhibited impaired insulin signaling and upregulated gluconeogenic gene expression and renal gluconeogenesis, resulting in systemic insulin resistance. In contrast, in streptozotocin-treated mice, although insulin action was impaired in the PTs, the gluconeogenic gene expression was unexpectedly downregulated in the renal cortex, which was restored by administration of an SGLT1/2 inhibitor. In the HK-2 cells, the gluconeogenic gene expression was suppressed by insulin, accompanied by phosphorylation and inactivation of forkhead box transcription factor 1 (FoxO1). In contrast, glucose deacetylated peroxisome proliferator-activated receptor γ coactivator 1-α (PGC1α), a coactivator of FoxO1, via sirtuin 1, suppressing the gluconeogenic gene expression, which was reversed by inhibition of glucose reabsorption. These data suggest that both insulin signaling and glucose reabsorption suppress the gluconeogenic gene expression by inactivation of FoxO1 and PGC1α, respectively, providing insight into novel mechanisms underlying the regulation of gluconeogenesis in the PTs. © 2017 by the American Diabetes Association.

Key differences between apoC-III regulation and expression in intestine and liver.

PubMed

West, Gabrielle; Rodia, Cayla; Li, Diana; Johnson, Zania; Dong, Hongli; Kohan, Alison B

2017-09-23

ApoC-III is a critical cardiovascular risk factor, and humans expressing null mutations in apoC-III are robustly protected from cardiovascular disease. Because of its critical role in elevating plasma lipids and CVD risk, hepatic apoC-III regulation has been studied at length. Considerably less is known about the factors that regulate intestinal apoC-III. In this work, we use primary murine enteroids, Caco-2 cells, and dietary studies in wild-type mice to show that intestinal apoC-III expression does not change in response to fatty acids, glucose, or insulin administration, in contrast to hepatic apoC-III. Intestinal apoC-III is not sensitive to changes in FoxO1 expression (which is itself very low in the intestine, as is FoxO1 target IGFBP-1), nor is intestinal apoC-III responsive to western diet, a significant contrast to hepatic apoC-III stimulation during western diet. These data strongly suggest that intestinal apoC-III is not a FoxO1 target and support the idea that apoC-III is not regulated coordinately with hepatic apoC-III, and establishes another key aspect of apoC-III that is unique in the intestine from the liver. Copyright © 2017 Elsevier Inc. All rights reserved.

The complete sequence of the mitochondrial genome of Arctic fox (Alopex lagopus).

PubMed

Yan, Shou-Qing; Guo, Peng-Cheng; Yue, Yuan; Li, Wan-Hong; Bai, Chun-Yan; Li, Yu-Mei; Sun, Jin-Hai; Zhao, Zhi-Hui

2016-11-01

In the present study, the complete mitochondrial genome sequence of Arctic fox (Alopex lagopus) was determined for the first time. It has a total length of 16,656 bp, and contains 13 protein-coding genes, 22 tRNA genes, 2 ribosome RNA genes and 1 control region. The nucleotide composition is 31.3% for A, 26.2% for C, 14.8% for G and 27.7% for T, respectively. The D-loop region located between tRNA Pro and tRNA Phe contains a (ACACGTACACGCAT) 18 tandem repeat array. The data will be useful for the investigation of the genetic structure and diversity in the natural and farmed population of Arctic foxes.

Aldehyde dehydrogenase 2 activation in aged heart improves the autophagy by reducing the carbonyl modification on SIRT1.

PubMed

Wu, Bing; Yu, Lu; Wang, Yishi; Wang, Hongtao; Li, Chen; Yin, Yue; Yang, Jingrun; Wang, Zhifa; Zheng, Qiangsun; Ma, Heng

2016-01-19

Cardiac aging is characterized by accumulation of damaged proteins and decline of autophagic efficiency. Here, by forestalling SIRT1 carbonylated inactivation in aged heart, we determined the benefits of activation of aldehyde dehydrogenase 2 (ALDH2) on the autophagy. In this study, the ALDH2 KO mice progressively developed age-related heart dysfunction and showed reduction in the life span, which strongly suggests that ALDH2 ablation leads to cardiac aging. What's more, aged hearts displayed a significant decrease ALDH2 activity, resulting in accumulation of 4-HNE-protein adducts and protein carbonyls, impairment in the autophagy flux, and, consequently, deteriorated cardiac function after starvation. Sustained Alda-1 (selective ALDH2 activator) treatment increased cardiac ALDH2 activity and abrogated these effects. Using SIRT1 deficient heterozygous (Sirt1+/-) mice, we found that SIRT1 was necessary for ALDH2 activation-induced autophagy. We further demonstrated that ALDH2 activation attenuated SIRT1 carbonylation and improved SIRT1 activity, thereby increasing the deacetylation of nuclear LC3 and FoxO1. Sequentially, ALDH2 enhanced SIRT1 regulates LC3-Atg7 interaction and FoxO1 increased Rab7 expression, which were both necessary and sufficient for restoring autophagy flux. These results highlight that both accumulation of proteotoxic carbonyl stress linkage with autophagy decline contribute to heart senescence. ALDH2 activation is adequate to improve the autophagy flux by reducing the carbonyl modification on SIRT1, which in turn plays an important role in maintaining cardiac health during aging.

Increased CD4+CD45RA-FoxP3low cells alter the balance between Treg and Th17 cells in colitis mice.

PubMed

Ma, Ya-Hui; Zhang, Jie; Chen, Xue; Xie, You-Fu; Pang, Yan-Hua; Liu, Xin-Juan

2016-11-14

To investigate the role of regulatory T cell (Treg) subsets in the balance between Treg and T helper 17 (Th17) cells in various tissues from mice with dextran sulfate sodium-induced colitis. Treg cells, Treg cell subsets, Th17 cells, and CD4 + CD25 + FoxP3 + IL-17 + cells from the lamina propria of colon (LPC) and other ulcerative colitis (UC) mouse tissues were evaluated by flow cytometry. Forkhead box protein 3 (FoxP3), interleukin 17A (IL-17A), and RORC mRNA levels were assessed by real-time PCR, while interleukin-10 (IL-10) and IL-17A levels were detected with a Cytometric Beads Array. In peripheral blood monocytes (PBMC), mesenteric lymph node (MLN), lamina propria of jejunum (LPJ) and LPC from UC mice, Treg cell numbers were increased ( P < 0.05), and FoxP3 and IL-10 mRNA levels were decreased. Th17 cell numbers were also increased in PBMC and LPC, as were IL-17A levels in PBMC, LPJ, and serum. The number of FrI subset cells (CD4 + CD45RA + FoxP3 low ) was increased in the spleen, MLN, LPJ, and LPC. FrII subset cells (CD4 + CD45RA - FoxP3 high ) were decreased among PBMC, MLN, LPJ, and LPC, but the number of FrIII cells (CD4 + CD45RA - FoxP3 low ) and CD4 + CD25 + FoxP3 + IL-17A + cells was increased. FoxP3 mRNA levels in CD4 + CD45RA - FoxP3 low cells decreased in PBMC, MLN, LPJ, and LPC in UC mice, while IL-17A and RORC mRNA increased. In UC mice the distribution of Treg, Th17 cells, CD4 + CD45RA - FoxP3 high , and CD4 + CD45RA - FoxP3 low cells was higher in LPC relative to other tissues. Increased numbers of CD4 + CD45RA - FoxP3 low cells may cause an imbalance between Treg and Th17 cells that is mainly localized to the LPC rather than secondary lymphoid tissues.

Increased CD4+CD45RA-FoxP3low cells alter the balance between Treg and Th17 cells in colitis mice

PubMed Central

Ma, Ya-Hui; Zhang, Jie; Chen, Xue; Xie, You-Fu; Pang, Yan-Hua; Liu, Xin-Juan

2016-01-01

AIM To investigate the role of regulatory T cell (Treg) subsets in the balance between Treg and T helper 17 (Th17) cells in various tissues from mice with dextran sulfate sodium-induced colitis. METHODS Treg cells, Treg cell subsets, Th17 cells, and CD4+CD25+FoxP3+IL-17+ cells from the lamina propria of colon (LPC) and other ulcerative colitis (UC) mouse tissues were evaluated by flow cytometry. Forkhead box protein 3 (FoxP3), interleukin 17A (IL-17A), and RORC mRNA levels were assessed by real-time PCR, while interleukin-10 (IL-10) and IL-17A levels were detected with a Cytometric Beads Array. RESULTS In peripheral blood monocytes (PBMC), mesenteric lymph node (MLN), lamina propria of jejunum (LPJ) and LPC from UC mice, Treg cell numbers were increased (P < 0.05), and FoxP3 and IL-10 mRNA levels were decreased. Th17 cell numbers were also increased in PBMC and LPC, as were IL-17A levels in PBMC, LPJ, and serum. The number of FrI subset cells (CD4+CD45RA+FoxP3low) was increased in the spleen, MLN, LPJ, and LPC. FrII subset cells (CD4+CD45RA-FoxP3high) were decreased among PBMC, MLN, LPJ, and LPC, but the number of FrIII cells (CD4+CD45RA-FoxP3low) and CD4+CD25+FoxP3+IL-17A+ cells was increased. FoxP3 mRNA levels in CD4+CD45RA-FoxP3low cells decreased in PBMC, MLN, LPJ, and LPC in UC mice, while IL-17A and RORC mRNA increased. In UC mice the distribution of Treg, Th17 cells, CD4+CD45RA-FoxP3high, and CD4+CD45RA-FoxP3low cells was higher in LPC relative to other tissues. CONCLUSION Increased numbers of CD4+CD45RA-FoxP3low cells may cause an imbalance between Treg and Th17 cells that is mainly localized to the LPC rather than secondary lymphoid tissues. PMID:27895423

Molecular Mechanism of Betaine on Hepatic Lipid Metabolism: Inhibition of Forkhead Box O1 (FoxO1) Binding to Peroxisome Proliferator-Activated Receptor Gamma (PPARγ).

PubMed

Kim, Dae Hyun; Lee, Bonggi; Kim, Min Jo; Park, Min Hi; An, Hye Jin; Lee, Eun Kyeong; Chung, Ki Wung; Park, June Whoun; Yu, Byung Pal; Choi, Jae Sue; Chung, Hae Young

2016-09-14

Betaine is a major water-soluble component of Lycium chinensis. Although there are reports about the protective effects of betaine on hepatic steatosis, the underlying mechanisms are unclear. We used db/db mice and HepG2 cells to examine the mechanism underlying betaine-mediated protection against hepatic steatosis. Here, we showed increased hepatic lipid accumulation in db/db mice, which is associated with increased activation of lipogenic transcription factors including forkhead box O1 (FoxO1) and peroxisome proliferator-activated receptor gamma (PPARγ), whereas betaine administration by oral gavage reversed these characteristics. We investigated whether betaine ameliorates hepatic steatosis by inhibiting FoxO1/PPARγ signaling in HepG2 cells. Although adenovirus-mediated FoxO1 overexpression notably increased mRNA expression levels of PPARγ and its target genes including FAS and ACC, betaine treatment reversed them. Furthermore, betaine inhibited FoxO1 binding to the PPARγ promoter and PPARγ transcriptional activity in HepG2 cells, which was previously shown to induce hepatic steatosis. We concluded that betaine ameliorates hepatic steatosis, at least in part, by inhibiting the FoxO1 binding to PPARγ and their downstream lipogenic signaling cascade.

Broad-spectrum protein kinase inhibition by the staurosporine analog KT-5720 reverses ethanol withdrawal-associated loss of NeuN/Fox-3.

PubMed

Reynolds, Anna R; Saunders, Meredith A; Berry, Jennifer N; Sharrett-Field, Lynda J; Winchester, Sydney; Prendergast, Mark A

2017-11-01

Chronic, intermittent ethanol (CIE) exposure is known to produce neuroadaptive alterations in excitatory neurotransmission that contribute to the development of dependence. Although activation of protein kinases (e.g., cyclic AMP [cAMP]-dependent protein kinase) is implicated in the synaptic trafficking of these receptors following CIE exposure, the functional consequences of these effects are yet to be fully understood. The present study sought to delineate the influence of protein kinase in regulating cytotoxicity following CIE exposure, as well as to examine the relative roles of ethanol exposure and ethanol withdrawal (EWD) in promoting these effects. Rat hippocampal explants were exposed to a developmental model of CIE with or without co-application of broad-spectrum protein kinase inhibitor KT-5720 (1 μM) either during ethanol exposure or EWD. Hippocampal cytotoxicity was assessed via immunofluorescence (IF) of neuron-specific nuclear protein (NeuN) with thionine staining of Nissl bodies to confirm IF findings. Concomitant application of ethanol and KT-5720 restored the loss of NeuN/Fox-3 IF in pyramidal CA1 and granule DG cell layers produced by CIE, but there was no restoration in CA3. Application of KT-5720 during EWD failed to significantly alter levels of NeuN IF, implying that ethanol exposure activates protein kinases that, in part, mediate the effects of EWD. KT-5720 application during EWD also restored thionine staining in CA1, suggesting kinase regulation of both neurons and non-neuronal cells. These data demonstrate that CIE exposure alters protein kinase activity to promote ethanol withdrawal-associated loss of NeuN/Fox-3 and highlight the influence of kinase signaling on distinct cell types in the developing hippocampus. Copyright © 2017 Elsevier Inc. All rights reserved.

Combined exposure to Maneb and Paraquat alters transcriptional regulation of neurogenesis-related genes in mice models of Parkinson's disease.

PubMed

Desplats, Paula; Patel, Pruthul; Kosberg, Kori; Mante, Michael; Patrick, Christina; Rockenstein, Edward; Fujita, Masayo; Hashimoto, Makoto; Masliah, Eliezer

2012-09-28

Parkinson's disease (PD) is a multifactorial disease where environmental factors act on genetically predisposed individuals. Although only 5% of PD manifestations are associated with specific mutations, majority of PD cases are of idiopathic origin, where environment plays a prominent role. Concurrent exposure to Paraquat (PQ) and Maneb (MB) in rural workers increases the risk for PD and exposure of adult mice to MB/PQ results in dopamine fiber loss and decreased locomotor activity. While PD is characterized by neuronal loss in the substantia nigra, we previously showed that accumulation of α-synuclein in the limbic system contributes to neurodegeneration by interfering with adult neurogenesis. We investigated the effect of pesticides on adult hippocampal neurogenesis in two transgenic models: Line 61, expressing the human wild type SNCA gene and Line LRRK2(G2019S), expressing the human LRRK2 gene with the mutation G2019S. Combined exposure to MB/PQ resulted in significant reduction of neuronal precursors and proliferating cells in non-transgenic animals, and this effect was increased in transgenic mice, in particular for Line 61, suggesting that α-synuclein accumulation and environmental toxins have a synergistic effect. We further investigated the transcription of 84 genes with direct function on neurogenesis. Overexpresion of α-synuclein resulted in the downregulation of 12% of target genes, most of which were functionally related to cell differentiation, while LRRK2 mutation had a minor impact on gene expression. MB/PQ also affected transcription in non-transgenic backgrounds, but when transgenic mice were exposed to the pesticides, profound alterations in gene expression affecting 27% of the studied targets were observed in both transgenic lines. Gene enrichment analysis showed that 1:3 of those genes were under the regulation of FoxF2 and FoxO3A, suggesting a primary role of these proteins in the response to genetic and environmental cues. We report that adult neurogenesis is highly susceptible to multiple "risk factors" for PD, including α-synuclein accumulation, LRRK2 G2019 mutation and exposure to environmental toxins. We identified specific groups of genes that are responsive to each stressor, while uncovering a novel function for Fox transcription factors in PD.

Triptolide Upregulates Myocardial Forkhead Helix Transcription Factor p3 Expression and Attenuates Cardiac Hypertrophy

PubMed Central

Ding, Yuan-Yuan; Li, Jing-Mei; Guo, Feng-Jie; Liu, Ya; Tong, Yang-Fei; Pan, Xi-Chun; Lu, Xiao-Lan; Ye, Wen; Chen, Xiao-Hong; Zhang, Hai-Gang

2016-01-01

The forkhead/winged helix transcription factor (Fox) p3 can regulate the expression of various genes, and it has been reported that the transfer of Foxp3-positive T cells could ameliorate cardiac hypertrophy and fibrosis. Triptolide (TP) can elevate the expression of Foxp3, but its effects on cardiac hypertrophy remain unclear. In the present study, neonatal rat ventricular myocytes (NRVM) were isolated and stimulated with angiotensin II (1 μmol/L) to induce hypertrophic response. The expression of Foxp3 in NRVM was observed by using immunofluorescence assay. Fifty mice were randomly divided into five groups and received vehicle (control), isoproterenol (Iso, 5 mg/kg, s.c.), one of three doses of TP (10, 30, or 90 μg/kg, i.p.) for 14 days, respectively. The pathological morphology changes were observed after Hematoxylin and eosin, lectin and Masson’s trichrome staining. The levels of serum brain natriuretic peptide (BNP) and troponin I were determined by enzyme-linked immunosorbent assay and chemiluminescence, respectively. The mRNA and protein expressions of α- myosin heavy chain (MHC), β-MHC and Foxp3 were determined using real-time PCR and immunohistochemistry, respectively. It was shown that TP (1, 3, 10 μg/L) treatment significantly decreased cell size, mRNA and protein expression of β-MHC, and upregulated Foxp3 expression in NRVM. TP also decreased heart weight index, left ventricular weight index and, improved myocardial injury and fibrosis; and decreased the cross-scetional area of the myocardium, serum cardiac troponin and BNP. Additionally, TP markedly reduced the mRNA and protein expression of myocardial β-MHC and elevated the mRNA and protein expression of α-MHC and Foxp3 in a dose-dependent manner. In conclusion, TP can effectively ameliorate myocardial damage and inhibit cardiac hypertrophy, which is at least partly related to the elevation of Foxp3 expression in cardiomyocytes. PMID:27965581

Activation of MAPK and FoxO by Manganese (Mn) in Rat Neonatal Primary Astrocyte Cultures

PubMed Central

Exil, Vernat; Ping, Li; Yu, Yingchun; Chakraborty, Sudipta; Caito, Samuel W.; Wells, K. Sam; Karki, Pratap; Lee, Eunsook; Aschner, Michael

2014-01-01

Environmental exposure to manganese (Mn) leads to a neurodegenerative disease that has shared clinical characteristics with Parkinson's disease (PD). Mn-induced neurotoxicity is time- and dose-dependent, due in part to oxidative stress. We ascertained the molecular targets involved in Mn-induced neurodegeneration using astrocyte culture as: (1) Astrocytes are vital for information processing within the brain, (2) their redox potential is essential in mitigating reactive oxygen species (ROS) levels, and (3) they are targeted early in the course of Mn toxicity. We first tested protein levels of Mn superoxide dismutase -2 (SOD-2) and glutathione peroxidase (GPx-1) as surrogates of astrocytic oxidative stress response. We assessed levels of the forkhead winged-helix transcription factor O (FoxO) in response to Mn exposure. FoxO is highly regulated by the insulin-signaling pathway. FoxO mediates cellular responses to toxic stress and modulates adaptive responses. We hypothesized that FoxO is fundamental in mediating oxidative stress response upon Mn treatment, and may be a biomarker of Mn-induced neurodegeneration. Our results indicate that 100 or 500 µM of MnCl2 led to increased levels of FoxO (dephosphorylated and phosphorylated) compared with control cells (P<0.01). p-FoxO disappeared from the cytosol upon Mn exposure. Pre-treatment of cultured cells with (R)-(−)-2-oxothiazolidine-4-carboxylic acid (OTC), a cysteine analog rescued the cytosolic FoxO. At these concentrations, MAPK phosphorylation, in particular p38 and ERK, and PPAR gamma coactivator-1 (PGC-1) levels were increased, while AKT phosphorylation remained unchanged. FoxO phosphorylation level was markedly reduced with the use of SB203580 (a p38 MAPK inhibitor) and PD98059 (an ERK inhibitor). We conclude that FoxO phosphorylation after Mn exposure occurs in parallel with, and independent of the insulin-signaling pathway. FoxO levels and its translocation into the nucleus are part of early events compensating for Mn-induced neurotoxicity and may serve as valuable targets for neuroprotection in the setting of Mn-induced neurodegeneration. PMID:24787138

The ThPOK transcription factor differentially affects the development and function of self-specific CD8(+) T cells and regulatory CD4(+) T cells.

PubMed

Twu, Yuh-Ching; Teh, Hung-Sia

2014-03-01

The zinc finger transcription factor ThPOK plays a crucial role in CD4 T-cell development and CD4/CD8 lineage decision. In ThPOK-deficient mice, developing T cells expressing MHC class II-restricted T-cell receptors are redirected into the CD8 T-cell lineage. In this study, we investigated whether the ThPOK transgene affected the development and function of two additional types of T cells, namely self-specific CD8 T cells and CD4(+) FoxP3(+) T regulatory cells. Self-specific CD8 T cells are characterized by high expression of CD44, CD122, Ly6C, 1B11 and proliferation in response to either IL-2 or IL-15. The ThPOK transgene converted these self-specific CD8 T cells into CD4 T cells. The converted CD4(+) T cells are no longer self-reactive, lose the characteristics of self-specific CD8 T cells, acquire the properties of conventional CD4 T cells and survive poorly in peripheral lymphoid organs. By contrast, the ThPOK transgene promoted the development of CD4(+) FoxP3(+) regulatory T cells resulting in an increased recovery of CD4(+) FoxP3(+) regulatory T cells that expressed higher transforming growth factor-β-dependent suppressor activity. These studies indicate that the ThPOK transcription factor differentially affects the development and function of self-specific CD8 T cells and CD4(+) FoxP3(+) regulatory T cells. © 2013 John Wiley & Sons Ltd.

Elk3 is essential for the progression from progenitor to definitive neural crest cell

PubMed Central

Rogers, Crystal D.; Phillips, Jacquelyn L.; Bronner, Marianne E.

2013-01-01

Elk3/Net/Sap2 (here referred to as Elk3) is an Ets ternary complex transcriptional repressor known for its involvement in angiogenesis during embryonic development. Although Elk3 is expressed in various tissues, additional roles for the protein outside of vasculature development have yet to be reported. Here, we characterize the early spatiotemporal expression pattern of Elk3 in the avian embryo using whole mount in situ hybridization and quantitative RT-PCR and examine the effects of its loss of function on neural crest development. At early stages, Elk3 is expressed in the head folds, head mesenchyme, intersomitic vessels, and migratory cranial neural crest (NC) cells. Loss of the Elk3 protein results in the retention of Pax7+ precursors in the dorsal neural tube that fail to upregulate neural crest specifier genes, FoxD3, Sox10 and Snail2, resulting in embryos with severe migration defects. The results putatively place Elk3 downstream of neural plate border genes, but upstream of neural crest specifier genes in the neural crest gene regulatory network (NC-GRN), suggesting that it is critical for the progression from progenitor to definitive neural crest cell. PMID:23266330

Effect of cell density and HLA-DR incompatibility on T-cell proliferation and forkhead box P3 expression in human mixed lymphocyte reaction.

PubMed

Song, E Y; Han, S; Yang, B; Morris, G P; Bui, J D

2015-04-01

The proliferation rates of human T cells in vitro are affected by some factors such as initial T-cell number, dose of stimulating cells, and duration of culture. The transcription factor forkhead box P3 (FoxP3) has been used to identify regulatory T cells in humans and is thought to correlate with tolerance to allogeneic organ transplant. Thus, it is important to optimize conditions to expand FoxP3 cell proliferation to improve engraftment of allogeneic organ transplants. We studied proliferative responses and FoxP3 expression in divided T cells with the use of flow cytometric analysis of Ki-67 in culture of different concentrations of responding cells (6 × 10(6), 4 × 10(6), 2 × 10(6), 1 × 10(6), and 0.5 × 10(6)cells/mL), different types of stimulating cells (lymphocytes and low density cells), and different numbers of HLA mismatches. The proportion of CD3(+) cells, CD4(+)CD25(+) cells, and CD4(+)CD25(+)FoxP3(+) cells among mononuclear cells were highest at initial cell concentration of 2 × 10(6) responder cells/mL with lymphocytes as stimulators at day-5 mixed lymphocyte reaction (MLR). They were highest at a concentration of 4 × 10(6) responder cells/mL with low density cells as stimulators. The recovery (%), proportion of CD3(+) cells, CD4(+)CD25(+) cells, and CD4(+)CD25(+)FoxP3(+) cells with 2 HLA-DR incompatibility were significantly higher than those of 1 HLA-DR incompatibility at day-5 MLR. Initial cell concentration and HLA-DR incompatibility can affect the generation of FoxP3+ T cells in human MLR. These factors could be considered for efficient generation of Tregs for clinical trials in the future. Copyright © 2015 Elsevier Inc. All rights reserved.

In silico study of protein to protein interaction analysis of AMP-activated protein kinase and mitochondrial activity in three different farm animal species

NASA Astrophysics Data System (ADS)

Prastowo, S.; Widyas, N.

2018-03-01

AMP-activated protein kinase (AMPK) is cellular energy censor which works based on ATP and AMP concentration. This protein interacts with mitochondria in determine its activity to generate energy for cell metabolism purposes. For that, this paper aims to compare the protein to protein interaction of AMPK and mitochondrial activity genes in the metabolism of known animal farm (domesticated) that are cattle (Bos taurus), pig (Sus scrofa) and chicken (Gallus gallus). In silico study was done using STRING V.10 as prominent protein interaction database, followed with biological function comparison in KEGG PATHWAY database. Set of genes (12 in total) were used as input analysis that are PRKAA1, PRKAA2, PRKAB1, PRKAB2, PRKAG1, PRKAG2, PRKAG3, PPARGC1, ACC, CPT1B, NRF2 and SOD. The first 7 genes belong to gene in AMPK family, while the last 5 belong to mitochondrial activity genes. The protein interaction result shows 11, 8 and 5 metabolism pathways in Bos taurus, Sus scrofa and Gallus gallus, respectively. The top pathway in Bos taurus is AMPK signaling pathway (10 genes), Sus scrofa is Adipocytokine signaling pathway (8 genes) and Gallus gallus is FoxO signaling pathway (5 genes). Moreover, the common pathways found in those 3 species are Adipocytokine signaling pathway, Insulin signaling pathway and FoxO signaling pathway. Genes clustered in Adipocytokine and Insulin signaling pathway are PRKAA2, PPARGC1A, PRKAB1 and PRKAG2. While, in FoxO signaling pathway are PRKAA2, PRKAB1, PRKAG2. According to that, we found PRKAA2, PRKAB1 and PRKAG2 are the common genes. Based on the bioinformatics analysis, we can demonstrate that protein to protein interaction shows distinct different of metabolism in different species. However, further validation is needed to give a clear explanation.

Two Membrane-Associated Tyrosine Phosphatase Homologs Potentiate C. elegans AKT-1/PKB Signaling

PubMed Central

Hu, Patrick J; Xu, Jinling; Ruvkun, Gary

2006-01-01

Akt/protein kinase B (PKB) functions in conserved signaling cascades that regulate growth and metabolism. In humans, Akt/PKB is dysregulated in diabetes and cancer; in Caenorhabditis elegans, Akt/PKB functions in an insulin-like signaling pathway to regulate larval development. To identify molecules that modulate C. elegans Akt/PKB signaling, we performed a genetic screen for enhancers of the akt-1 mutant phenotype (eak). We report the analysis of three eak genes. eak-6 and eak-5/sdf-9 encode protein tyrosine phosphatase homologs; eak-4 encodes a novel protein with an N-myristoylation signal. All three genes are expressed primarily in the two endocrine XXX cells, and their predicted gene products localize to the plasma membrane. Genetic evidence indicates that these proteins function in parallel to AKT-1 to inhibit the FoxO transcription factor DAF-16. These results define two membrane-associated protein tyrosine phosphatase homologs that may potentiate C. elegans Akt/PKB signaling by cell autonomous and cell nonautonomous mechanisms. Similar molecules may modulate Akt/PKB signaling in human endocrine tissues. PMID:16839187

Apigenin inhibits prostate cancer progression in TRAMP mice via targeting PI3K/Akt/FoxO pathway

PubMed Central

Gupta, Sanjay

2014-01-01

Forkhead box O (FoxO) transcription factors play an important role as tumor suppressor in several human malignancies. Disruption of FoxO activity due to loss of phosphatase and tensin homolog and activation of phosphatidylinositol-3 kinase (PI3K)/Akt are frequently observed in prostate cancer. Apigenin, a naturally occurring plant flavone, exhibits antiproliferative and anticarcinogenic activities through mechanisms, which are not fully defined. In the present study, we show that apigenin suppressed prostate tumorigenesis in transgenic adenocarcinoma of the mouse prostate (TRAMP) mice through the PI3K/Akt/FoxO-signaling pathway. Apigenin-treated TRAMP mice (20 and 50 μg/mouse/day, 6 days/week for 20 weeks) exhibited significant decrease in tumor volumes of the prostate as well as completely abolished distant organ metastasis. Apigenin treatment resulted in significant decrease in the weight of genitourinary apparatus (P < 0.0001), dorsolateral (P < 0.0001) and ventral prostate (P < 0.028), compared with the control group. Apigenin-treated mice showed reduced phosphorylation of Akt (Ser473) and FoxO3a (Ser253), which correlated with its increased nuclear retention and decreased binding of FoxO3a with 14-3-3. These events lead to reduced proliferation as assessed by Ki-67 and cyclin D1, along with upregulation of FoxO-responsive proteins BIM and p27/Kip1. Complementing in vivo results, similar observations were noted in human prostate cancer LNCaP and PC-3 cells after apigenin treatment. Furthermore, binding of FoxO3a with p27/Kip1 was markedly increased after 10 and 20 μM apigenin treatment resulting in G0/G1-phase cell cycle arrest, which was consistent with the effects elicited by PI3K/Akt inhibitor, LY294002. These results provide convincing evidence that apigenin effectively suppressed prostate cancer progression, at least in part, by targeting the PI3K/Akt/FoxO-signaling pathway. PMID:24067903

Aberrant Muscle Antigen Exposure in Mice Is Sufficient to Cause Myositis in a Treg Cell–Deficient Milieu

PubMed Central

Young, Nicholas A; Sharma, Rahul; Friedman, Alexandra K; Kaffenberger, Benjamin H; Bolon, Brad; Jarjour, Wael N

2013-01-01

Objective Myositis is associated with muscle-targeted inflammation and is observed in some Treg cell–deficient mouse models. Because an autoimmune pathogenesis has been strongly implicated, the aim of this study was to investigate the hypothesis that abnormal exposure to muscle antigens, as observed in muscle injury, can induce autoimmune-mediated myositis in susceptible hosts. Methods FoxP3 mutant (scurfy) mice were mated to synaptotagmin VII (Syt VII) mutant mice, which resulted in a new mouse strain that combines impaired membrane resealing with Treg cell deficiency. Lymphocyte preparations from double-mutant mice were adoptively transferred intraperitoneally, with or without purified Treg cells, into recombination-activating gene 1 (RAG-1)–null recipients. Lymph node cells from mice with the FoxP3 mutation were transferred into RAG-1–null mice either 1) intraperitoneally in conjunction with muscle homogenate or purified myosin protein or 2) intramuscularly with or without cotransfer of purified Treg cells. Results FoxP3-deficient mouse lymph node cells transferred in conjunction with myosin protein or muscle homogenate induced robust skeletal muscle inflammation. The infiltrates consisted predominantly of CD4+ and CD8+ T cells, a limited number of macrophages, and no B cells. Significant inflammation was also seen in similar experiments using lymph node cells from FoxP3/Syt VII double-mutant mice but was absent in experiments using adoptive transfer of FoxP3 mutant mouse cells alone. The cotransfer of Treg cells completely suppressed myositis. Conclusion These data, derived from a new, reproducible model, demonstrate the critical roles of Treg cell deficiency and aberrant muscle antigen exposure in the priming of autoreactive cells to induce myositis. This mouse system has multifaceted potential for examining the interplay in vivo between tissue injury and autoimmunity. PMID:24022275

Smad3 induces atrogin-1, inhibits mTOR and protein synthesis, and promotes muscle atrophy in vivo.

PubMed

Goodman, Craig A; McNally, Rachel M; Hoffmann, F Michael; Hornberger, Troy A

2013-11-01

Myostatin, a member of the TGF superfamily, is sufficient to induce skeletal muscle atrophy. Myostatin-induced atrophy is associated with increases in E3-ligase atrogin-1 expression and protein degradation and decreases in Akt/mechanistic target of rapamycin (mTOR) signaling and protein synthesis. Myostatin signaling activates the transcription factor Smad3 (Small Mothers Against Decapentaplegic), which has been shown to be necessary for myostatin-induced atrogin-1 expression and atrophy; however, it is not known whether Smad3 is sufficient to induce these events or whether Smad3 simply plays a permissive role. Thus, the aim of this study was to address these questions with an in vivo model. To accomplish this goal, in vivo transfection of plasmid DNA was used to create transient transgenic mouse skeletal muscles, and our results show for the first time that Smad3 expression is sufficient to stimulate atrogin-1 promoter activity, inhibit Akt/mTOR signaling and protein synthesis, and induce muscle fiber atrophy. Moreover, we propose that Akt/mTOR signaling is inhibited by a Smad3-induced decrease in microRNA-29 (miR-29) expression and a subsequent increase in the translation of phosphatase and tensin homolog (PTEN) mRNA. Smad3 is also sufficient to inhibit peroxisome proliferator-activated receptor-γ coactivator-1α (PGC1α) promoter activity and to increase FoxO (Forkhead Box Protein, Subclass O)-mediated signaling and the promoter activity of plasminogen activator inhibitor 1 (PAI-1). Combined, this study provides the first evidence that Smad3 is sufficient to regulate many of the events associated with myostatin-induced atrophy and therefore suggests that Smad3 signaling may be a viable target for therapies aimed at preventing myostatin-induced muscle atrophy.

daf-16/FoxO promotes gluconeogenesis and trehalose synthesis during starvation to support survival

PubMed Central

Hibshman, Jonathan D; Doan, Alexander E; Moore, Brad T; Kaplan, Rebecca EW; Hung, Anthony; Webster, Amy K; Bhatt, Dhaval P; Chitrakar, Rojin; Hirschey, Matthew D

2017-01-01

daf-16/FoxO is required to survive starvation in Caenorhabditis elegans, but how daf-16IFoxO promotes starvation resistance is unclear. We show that daf-16/FoxO restructures carbohydrate metabolism by driving carbon flux through the glyoxylate shunt and gluconeogenesis and into synthesis of trehalose, a disaccharide of glucose. Trehalose is a well-known stress protectant, capable of preserving membrane organization and protein structure during abiotic stress. Metabolomic, genetic, and pharmacological analyses confirm increased trehalose synthesis and further show that trehalose not only supports survival as a stress protectant but also serves as a glycolytic input. Furthermore, we provide evidence that metabolic cycling between trehalose and glucose is necessary for this dual function of trehalose. This work demonstrates that daf-16/FoxO promotes starvation resistance by shifting carbon metabolism to drive trehalose synthesis, which in turn supports survival by providing an energy source and acting as a stress protectant. PMID:29063832

Clinical and experimental advances in congenital and paediatric cataracts

PubMed Central

Churchill, Amanda; Graw, Jochen

2011-01-01

Cataracts (opacities of the lens) are frequent in the elderly, but rare in paediatric practice. Congenital cataracts (in industrialized countries) are mainly caused by mutations affecting lens development. Much of our knowledge about the underlying mechanisms of cataractogenesis has come from the genetic analysis of affected families: there are contributions from genes coding for transcription factors (such as FoxE3, Maf, Pitx3) and structural proteins such as crystallins or connexins. In addition, there are contributions from enzymes affecting sugar pathways (particularly the galactose pathway) and from a quite unexpected area: axon guidance molecules like ephrins and their receptors. Cataractous mouse lenses can be identified easily by visual inspection, and a remarkable number of mutant lines have now been characterized. Generally, most of the mouse mutants show a similar phenotype to their human counterparts; however, there are some remarkable differences. It should be noted that many mutations affect genes that are expressed not only in the lens, but also in tissues and organs outside the eye. There is increasing evidence for pleiotropic effects of these genes, and increasing consideration that cataracts may act as early and readily detectable biomarkers for a number of systemic syndromes. PMID:21402583

TGF-β converts apoptotic stimuli into the signal for Th9 differentiation

PubMed Central

Takami, Mariko; Love, Robert B.; Iwashima, Makio

2012-01-01

Naturally arising CD4+CD25+FoxP3+ regulatory T cells (nTregs) play an essential role in maintenance of immune homeostasis and peripheral tolerance. Previously, we reported that conventional CD4+ and CD8+ T cells undergo p53-induced CD28-dependent apoptosis (PICA) when stimulated with a combination of immobilized anti-CD3 and anti-CD28 antibodies while nTregs expand robustly under the same conditions, suggesting that there is a differential survival mechanism against PICA between conventional T cells and nTregs. Here, we demonstrate that TGF-β signaling is required for nTregs to survive PICA. Conversely, when an active form of exogenous TGF-β is present, conventional T cells become resistant to PICA and undergo robust expansion instead of apoptosis, with reduction of the pro-apoptotic protein Bim and FoxO3a. A substantial fraction of PICA-resisted T cells expressed IL-9 (TH9 cells). Moreover, the presence of IL-6 along with TGF-β led to generation of TH17 cells from conventional T cells. Together, the data demonstrate a novel role for TGF-β in the homeostasis of Tregs and effector T cell differentiation/ expansion. PMID:22461692

Detection of expressional changes induced by intrauterine growth restriction in the developing rat pancreas

PubMed Central

Zhang, Lin; Chen, Wei; Dai, Yuee

2016-01-01

Intrauterine growth retardation (IUGR) is a disorder that can result in permanent changes in the physiology and metabolism of the newborn, which increased the risk of disease in adulthood. Evidence supports IUGR as a risk factor for the development of diabetes mellitus, which could reflect changes in pancreas developmental pathways. We sought to characterize the IUGR-induced alterations of the complex pathways of pancreas development in a rat model of IUGR. We analyzed the pancreases of Sprague Dawley rats after inducing IUGR by feeding a maternal low calorie diet from gestational day 1 until term. IUGR altered the pancreatic structure, islet areas, and islet quantities and resulted in abnormal morphological changes during pancreatic development, as determined by HE staining and light microscopy. We identified multiple differentially expressed genes in the pancreas by RT-PCR. The genes of the insulin/FoxO1/Pdx1/MafA signaling pathway were first expressed at embryonic day 14 (E14). The expressions of insulin and MafA increased as the fetus grew while the expressions of FoxO1 and Pdx1 decreased. Compared with the control rats, the expressions of FoxO1, Pdx1, and MafA were lower in the IUGR rats, whereas insulin levels showed no change. Microarray profiling, in combination with quantitative real-time PCR, uncovered a subset of microRNAs that changed in their degree of expression throughout pancreatic development. In conclusion, our data support the hypothesis that IUGR influences the development of the rat pancreas. We also identified new pathways that appear to be programmed by IUGR. PMID:27190278

iTRAQ proteomics analysis reveals that PI3K is highly associated with bupivacaine-induced neurotoxicity pathways.

PubMed

Zhao, Wei; Liu, Zhongjie; Yu, Xujiao; Lai, Luying; Li, Haobo; Liu, Zipeng; Li, Le; Jiang, Shan; Xia, Zhengyuan; Xu, Shi-yuan

2016-02-01

Bupivacaine, a commonly used local anesthetic, has potential neurotoxicity through diverse signaling pathways. However, the key mechanism of bupivacaine-induced neurotoxicity remains unclear. Cultured human SH-SY5Y neuroblastoma cells were treated (bupivacaine) or untreated (control) with bupivacaine for 24 h. Compared to the control group, bupivacaine significantly increased cyto-inhibition, cellular reactive oxygen species, DNA damage, mitochondrial injury, apoptosis (increased TUNEL-positive cells, cleaved caspase 3, and Bcl-2/Bax), and activated autophagy (enhanced LC3II/LC3I ratio). To explore changes in protein expression and intercommunication among the pathways involved in bupivacaine-induced neurotoxicity, an 8-plex iTRAQ proteomic technique and bioinformatics analysis were performed. Compared to the control group, 241 differentially expressed proteins were identified, of which, 145 were up-regulated and 96 were down-regulated. Bioinformatics analysis of the cross-talk between the significant proteins with altered expression in bupivacaine-induced neurotoxicity indicated that phosphatidyl-3-kinase (PI3K) was the most frequently targeted protein in each of the interactions. We further confirmed these results by determining the downstream targets of the identified signaling pathways (PI3K, Akt, FoxO1, Erk, and JNK). In conclusion, our study demonstrated that PI3K may play a central role in contacting and regulating the signaling pathways that contribute to bupivacaine-induced neurotoxicity. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Myocardial regeneration in adriamycin cardiomyopathy by nuclear expression of GLP1 using ultrasound targeted microbubble destruction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Shuyuan; Chen, Jiaxi; Huang, Pintong

Recently GLP-1 was found to have cardioprotective effects independent of those attributable to tight glycemic control. Methods and results: We employed ultrasound targeted microbubble destruction (UTMD) to deliver piggybac transposon plasmids encoding the GLP-1 gene with a nuclear localizing signal to rat hearts with adriamycin cardiomyopathy. After a single UTMD treatment, overexpression of transgenic GLP-1 was found in nuclei of rat heart cells with evidence that transfected cardiac cells had undergone proliferation. UTMD-GLP-1 gene therapy restored LV mass, fractional shortening index, and LV posterior wall diameter to nearly normal. Nuclear overexpression of GLP-1 by inducing phosphorylation of FoxO1-S256 and translocationmore » of FoxO1 from the nucleus to the cytoplasm significantly inactivated FoxO1 and activated the expression of cyclin D1 in nuclei of cardiac muscle cells. Reversal of adriamycin cardiomyopathy appeared to be mediated by dedifferentiation and proliferation of nuclear FoxO1-positive cardiac muscle cells with evidence of embryonic stem cell markers (OCT4, Nanog, SOX2 and c-kit), cardiac early differentiation markers (NKX2.5 and ISL-1) and cellular proliferation markers (BrdU and PHH3) after UTMD with GLP-1 gene therapy. Conclusions: Intranuclear myocardial delivery of the GLP-1gene can reverse established adriamycin cardiomyopathy by stimulating myocardial regeneration. - Highlights: • The activation of nuclear FoxO1 in cardiac muscle cells associated with adriamycin cardiomyopathy. • Myocardial nuclear GLP-1 stimulates myocardial regeneration and reverses adriamycin cardiomyopathy. • The process of myocardial regeneration associated with dedifferentiation and proliferation.« less

Biphasic influence of Miz1 on neural crest development by regulating cell survival and apical adhesion complex formation in the developing neural tube

PubMed Central

Kerosuo, Laura; Bronner, Marianne E.

2014-01-01

Myc interacting zinc finger protein-1 (Miz1) is a transcription factor known to regulate cell cycle– and cell adhesion–related genes in cancer. Here we show that Miz1 also plays a critical role in neural crest development. In the chick, Miz1 is expressed throughout the neural plate and closing neural tube. Its morpholino-mediated knockdown affects neural crest precursor survival, leading to reduction of neural plate border and neural crest specifier genes Msx-1, Pax7, FoxD3, and Sox10. Of interest, Miz1 loss also causes marked reduction of adhesion molecules (N-cadherin, cadherin6B, and α1-catenin) with a concomitant increase of E-cadherin in the neural folds, likely leading to delayed and decreased neural crest emigration. Conversely, Miz1 overexpression results in up-regulation of cadherin6B and FoxD3 expression in the neural folds/neural tube, leading to premature neural crest emigration and increased number of migratory crest cells. Although Miz1 loss effects cell survival and proliferation throughout the neural plate, the neural progenitor marker Sox2 was unaffected, suggesting a neural crest–selective effect. The results suggest that Miz1 is important not only for survival of neural crest precursors, but also for maintenance of integrity of the neural folds and tube, via correct formation of the apical adhesion complex therein. PMID:24307680

Supplementation of Magnolol Attenuates Skeletal Muscle Atrophy in Bladder Cancer-Bearing Mice Undergoing Chemotherapy via Suppression of FoxO3 Activation and Induction of IGF-1.

PubMed

Chen, Meng-Chuan; Chen, Yen-Lin; Lee, Chi-Feng; Hung, Chih-Huang; Chou, Tz-Chong

2015-01-01

Skeletal muscle atrophy, the most prominent phenotypic feature of cancer cachexia, is often observed in cancer patients undergoing chemotherapy. Magnolol (M) extracted from Magnolia officinalis exhibits several pharmacological effects including anti-inflammatory and anticancer activities. In this study, we investigated whether magnolol supplementation protects against the development of cachexia symptoms in bladder cancer-bearing mice undergoing chemotherapy. Combined treatment of magnolol with chemotherapeutic drugs, such as gemcitabine and cisplatin (TGCM) or gemcitabine (TGM), markedly attenuates the body weight loss and skeletal muscle atrophy compared with conventional chemotherapy (TGC). The antiatrophic effect of magnolol may be associated with inhibition of myostatin and activin A formation, as well as FoxO3 transcriptional activity resulting from Akt activation, thereby suppressing ubiquitin ligases MuRF-1 and MAFbx/atrogin-1 expression, as well as proteasomal enzyme activity. Notably, magnolol-induced insulin-like growth factor 1 (IGF-1) production and related protein synthesis may also contribute to its protective effects. The decreased food intake, and intestinal injury and dysfunction observed in the mice of TGC group were significantly improved in the TGCM and TGM groups. Moreover, the increased inflammatory responses evidenced by elevation of proinflammatory cytokine formation and NF-κB activation occurred in the atrophying muscle of TGC group were markedly inhibited in mice of combined treatment with magnolol. In summary, these findings support that magnolol is a promising chemopreventive supplement for preventing chemotherapy-induced skeletal muscle atrophy associated with cancer cachexia by suppressing muscle protein degradation, and inflammatory responses, as well as increasing IGF-1-mediated protein synthesis.

Supplementation of Magnolol Attenuates Skeletal Muscle Atrophy in Bladder Cancer-Bearing Mice Undergoing Chemotherapy via Suppression of FoxO3 Activation and Induction of IGF-1

PubMed Central

Chen, Meng-Chuan; Chen, Yen-Lin; Lee, Chi-Feng; Hung, Chih-Huang; Chou, Tz-Chong

2015-01-01

Skeletal muscle atrophy, the most prominent phenotypic feature of cancer cachexia, is often observed in cancer patients undergoing chemotherapy. Magnolol (M) extracted from Magnolia officinalis exhibits several pharmacological effects including anti-inflammatory and anticancer activities. In this study, we investigated whether magnolol supplementation protects against the development of cachexia symptoms in bladder cancer-bearing mice undergoing chemotherapy. Combined treatment of magnolol with chemotherapeutic drugs, such as gemcitabine and cisplatin (TGCM) or gemcitabine (TGM), markedly attenuates the body weight loss and skeletal muscle atrophy compared with conventional chemotherapy (TGC). The antiatrophic effect of magnolol may be associated with inhibition of myostatin and activin A formation, as well as FoxO3 transcriptional activity resulting from Akt activation, thereby suppressing ubiquitin ligases MuRF-1 and MAFbx/atrogin-1 expression, as well as proteasomal enzyme activity. Notably, magnolol-induced insulin-like growth factor 1 (IGF-1) production and related protein synthesis may also contribute to its protective effects. The decreased food intake, and intestinal injury and dysfunction observed in the mice of TGC group were significantly improved in the TGCM and TGM groups. Moreover, the increased inflammatory responses evidenced by elevation of proinflammatory cytokine formation and NF-κB activation occurred in the atrophying muscle of TGC group were markedly inhibited in mice of combined treatment with magnolol. In summary, these findings support that magnolol is a promising chemopreventive supplement for preventing chemotherapy-induced skeletal muscle atrophy associated with cancer cachexia by suppressing muscle protein degradation, and inflammatory responses, as well as increasing IGF-1-mediated protein synthesis. PMID:26600425

Effect of lifelong football training on the expression of muscle molecular markers involved in healthy longevity.

PubMed

Mancini, A; Vitucci, D; Labruna, G; Imperlini, E; Randers, M B; Schmidt, J F; Hagman, M; Andersen, T R; Russo, R; Orrù, S; Krustrup, P; Salvatore, F; Buono, P

2017-04-01

We investigated whether lifelong football training affects the expression of healthy longevity-related muscle molecular markers. Biopsies were collected from the vastus lateralis muscle of 10 lifelong football-trained men (68.2 ± 3.0 years) and of 10 active untrained healthy men (66.7 ± 1.3 years). Gene and protein expression was measured by RTqPCR on RNA and by western blotting on protein extracts from muscle biopsies, respectively. The expression of AMPKα1/α2, NAMPT, TFAM and PGC1α, which are markers of oxidative metabolism, and MyHC β isoform expression was higher in the muscle of football-trained men vs untrained men. Also citrate synthase activity was higher in trained than in untrained men (109.3 ± 9.2 vs 75.1 ± 9.2 mU/mg). These findings were associated with a healthier body composition in trained than in untrained men [body weight: 78.2 ± 6.5 vs 91.2 ± 11.2 kg; body mass index BMI: 24.4 ± 1.6 vs 28.8 ± 4.0 kg m -2 ; fat%: 22.6 ± 8.0 vs 31.4 ± 5.0%)] and with a higher maximal oxygen uptake (VO 2 max: 34.7 ± 3.8 vs 27.3 ± 4.0 ml/min/kg). Also the expression of proteins involved in DNA repair and in senescence suppression (Erk1/2, Akt and FoxM1) was higher in trained than in untrained men. At BMI- and age-adjusted multiple linear regression analysis, fat percentage was independently associated with Akt protein expression, and VO 2 max was independently associated with TFAM mRNA and with Erk1/2 protein expression. Lifelong football training increases the expression of key markers involved in muscle oxidative metabolism, and in the DNA repair and senescence suppression pathways, thus providing the molecular basis for healthy longevity.

Hydrogen protects against hyperoxia-induced apoptosis in type II alveolar epithelial cells via activation of PI3K/Akt/Foxo3a signaling pathway.

PubMed

Wu, Dan; Liang, Mulin; Dang, Hongxing; Fang, Fang; Xu, Feng; Liu, Chengjun

2018-01-08

Oxidative stress is regarded as a key regulator in the pathogenesis of prolonged hyperoxia-induced lung injury, which causes injury to alveolar epithelial cells and eventually leads to development of bronchopulmonary dysplasia (BPD). Many studies have shown that hydrogen has a protective effect in a variety of cells. However, the mechanisms by which hydrogen rescues cells from damage due to oxidative stress in BPD remains to be fully elucidated. This study sought to evaluate the effects of hydrogen on hyperoxia-induced lung injury and to investigate the underlying mechanism. Primary type II alveolar epithelial cells (AECIIs) were divided into four groups: control (21% oxygen), hyperoxia (95% oxygen), hyperoxia + hydrogen, and hyperoxia + hydrogen + LY294002 (a PI3K/Akt inhibitor). Proliferation and apoptosis of AECIIs were assessed using MTS assay and flow cytometry (FCM), respectively. Gene and protein expression were detected by quantitative polymerase chain reaction (q-PCR) and western blot analysis. Stimulation with hyperoxia decreased the expression of P-Akt, P- FoxO3a, cyclinD1 and Bcl-2. Hyperoxic conditions increased levels of Bim, Bax, and Foxo3a, which induced proliferation restriction and apoptosis of AECIIs. These effects of hyperoxia were reversed with hydrogen pretreatment. Furthermore, the protective effects of hydrogen were abrogated by PI3K/Akt inhibitor LY294002. The results indicate that hydrogen protects AECIIs from hyperoxia-induced apoptosis by inhibiting apoptosis factors and promoting the expression of anti-apoptosis factors. These effects were associated with activation of the PI3K/Akt/FoxO3a pathway. Copyright © 2017 Elsevier Inc. All rights reserved.

IL-6 inhibits upregulation of membrane-bound TGF-beta 1 on CD4+ T cells and blocking IL-6 enhances oral tolerance

PubMed Central

Kuhn, Chantal; Rezende, Rafael Machado; M'Hamdi, Hanane; da Cunha, Andre Pires; Weiner, Howard L.

2016-01-01

Oral administration of antigen induces regulatory T cells that express latent membrane-bound TGF-beta (LAP) and that have been shown to play an important role in the induction of oral tolerance. We developed an in vitro model to study modulation of LAP+ on CD4+ T cells. The combination of anti-CD3 mAb, anti-CD28 mAb and recombinant IL-2 induced expression of LAP on naïve CD4+ T cells, independent of FoxP3 or exogenous TGF-β. In vitro generated CD4+LAP+FoxP3− T cells were suppressive in vitro, inhibiting proliferation of naïve CD4+ T cells and IL-17A secretion by Th17 cells. Assessing the impact of different cytokines and neutralizing antibodies against cytokines we found that LAP induction was decreased in the presence of IL-6 and IL-21, and to a lesser extent by IL-4 and TNFα. IL-6 abrogated the in vitro induction of CD4+LAP+ T cells by STAT3 dependent inhibition of Lrrc32 (GARP), the adapter protein that tethers TGF-beta to the membrane. Oral tolerance induction was enhanced in mice lacking expression of IL-6R by CD4+ T cells and by treatment of wild-type mice with neutralizing anti-IL-6 mAb. These results suggest that pro-inflammatory cytokines interfere with oral tolerance induction and that blocking the IL-6 pathway is a potential strategy for enhancing oral tolerance in the setting of autoimmune and inflammatory diseases. PMID:28039301

Induction of HO-1 by carbon monoxide releasing molecule-2 attenuates thrombin-induced COX-2 expression and hypertrophy in primary human cardiomyocytes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chien, Peter Tzu-Yu; Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Kwei-Shan, Tao-Yuan, Taiwan; Lin, Chih-Chung

Carbon monoxide (CO) is one of the cytoprotective byproducts of heme oxygenase (HO)-1 and exerts anti-inflammatory action in various models. However, the detailed mechanisms underlying CO-induced HO-1 expression in primary human cardiomyocytes remain largely unidentified. We used primary left ventricle myocytes as a model and applied CO releasing molecule (CORM)-2 to investigate the relationship of CO and HO-1 expression. We herein used Western blot, real-time PCR, promoter activity and EIA to investigate the role of HO-1 expression protecting against thrombin-mediated responses. We found that thrombin-induced COX-2 expression, PGE{sub 2} release and cardiomyocyte hypertrophy markers (increase in ANF/BNP, α-actin expression andmore » cell surface area) was attenuated by pretreatment with CORM-2 which was partially reversed by hemoglobin (Hb) or ZnPP (an inhibitor of HO-1 activity), suggesting that HO-1/CO system may be of clinical importance to ameliorate heart failure through inhibition of inflammatory responses. CORM-2-induced HO-1 protein expression, mRNA and promoter was attenuated by pretreatment with the inhibitors of Pyk2 (PF431396), PDGFR (AG1296), PI3K (LY294002), Akt (SH-5), p38 (SB202530), JNK1/2 (SP600125), FoxO1 (AS1842856) and Sp1 (mithramycin A). The involvement of these signaling components was further confirmed by transfection with respective siRNAs, consistent with those of pharmacological inhibitors. These results suggested that CORM-2-induced HO-1 expression is mediated through a Pyk2/PDGFR/PI3K/Akt/FoxO1/Sp1-dependent manner and exerts a cytoprotective effect in human cardiomyocytes. - Graphical abstract: In summary, CORM-2 treatment induces Pyk2 transactivated PDGFR, which induces PI3K/Akt/MAPK activation, and then recruits Sp1/Foxo1 transcriptional factors to regulate HO-1 gene expression in primary human cardiomyocytes. - Highlights: • CORM-2 induces HO-1 expression. • Pyk2-dependent PDGFR activates PI3K/Akt/MAPK pathway in CORM-2-induced HO-1 expression. • Transcriptional regulation of HO-1 expression is mediated by Sp1/Foxo1. • CO/HO-1 systems ameliorate thrombin-induced human cardiomyocyte hypertrophy.« less

Temporal variability in arctic fox diet as reflected in stable-carbon isotopes; the importance of sea ice.

PubMed

Roth, James D

2002-09-01

Consumption of marine foods by terrestrial predators can lead to increased predator densities, potentially impacting their terrestrial resources. For arctic foxes (Alopex lagopus), access to such marine foods in winter depends on sea ice, which is threatened by global climate change. To quantify the importance of marine foods (seal carrion and seal pups) and document temporal variation in arctic fox diet I measured the ratios of the stable isotopes of carbon ((13)C/(12)C) in hair of arctic foxes near Cape Churchill, Manitoba, from 1994 to 1997. These hair samples were compared to the stable carbon isotope ratios of several prey species. Isotopic differences between seasonally dimorphic pelage types indicated a diet with a greater marine content in winter when sea ice provided access to seal carrion. Annual variation in arctic fox diet in both summer and winter was correlated with lemming abundance. Marine food sources became much more important in winters with low lemming populations, accounting for nearly half of the winter protein intake following a lemming decline. Potential alternative summer foods with isotopic signatures differing from lemmings included goose eggs and caribou, but these were unavailable in winter. Reliance on marine food sources in winter during periods of low lemming density demonstrates the importance of the sea ice as a potential habitat for this arctic fox population and suggests that a continued decline in sea ice extent will disrupt an important link between the marine and terrestrial ecosystems.

An endogenous aryl hydrocarbon receptor ligand acts on dendritic cells and T cells to suppress experimental autoimmune encephalomyelitis

PubMed Central

Quintana, Francisco J.; Murugaiyan, Gopal; Farez, Mauricio F.; Mitsdoerffer, Meike; Tukpah, Ann-Marcia; Burns, Evan J.; Weiner, Howard L.

2010-01-01

The ligand-activated transcription factor aryl hydrocarbon receptor (AHR) participates in the differentiation of FoxP3+ Treg, Tr1 cells, and IL-17–producing T cells (Th17). Most of our understanding on the role of AHR on the FoxP3+ Treg compartment results from studies using the toxic synthetic chemical 2,3,7,8-tetrachlorodibenzo-p-dioxin. Thus, the physiological relevance of AHR signaling on FoxP3+ Treg in vivo is unclear. We studied mice that carry a GFP reporter in the endogenous foxp3 locus and a mutated AHR protein with reduced affinity for its ligands, and found that AHR signaling participates in the differentiation of FoxP3+ Treg in vivo. Moreover, we found that treatment with the endogenous AHR ligand 2-(1′H-indole-3′-carbonyl)-thiazole-4-carboxylic acid methyl ester (ITE) given parenterally or orally induces FoxP3+ Treg that suppress experimental autoimmune encephalomyelitis. ITE acts not only on T cells, but also directly on dendritic cells to induce tolerogenic dendritic cells that support FoxP3+ Treg differentiation in a retinoic acid-dependent manner. Thus, our work demonstrates that the endogenous AHR ligand ITE promotes the induction of active immunologic tolerance by direct effects on dendritic and T cells, and identifies nontoxic endogenous AHR ligands as potential unique compounds for the treatment of autoimmune disorders. PMID:21068375

JunB transcription factor maintains skeletal muscle mass and promotes hypertrophy

PubMed Central

Raffaello, Anna; Milan, Giulia; Masiero, Eva; Carnio, Silvia; Lee, Donghoon

2010-01-01

The size of skeletal muscle cells is precisely regulated by intracellular signaling networks that determine the balance between overall rates of protein synthesis and degradation. Myofiber growth and protein synthesis are stimulated by the IGF-1/Akt/mammalian target of rapamycin (mTOR) pathway. In this study, we show that the transcription factor JunB is also a major determinant of whether adult muscles grow or atrophy. We found that in atrophying myotubes, JunB is excluded from the nucleus and that decreasing JunB expression by RNA interference in adult muscles causes atrophy. Furthermore, JunB overexpression induces hypertrophy without affecting satellite cell proliferation and stimulated protein synthesis independently of the Akt/mTOR pathway. When JunB is transfected into denervated muscles, fiber atrophy is prevented. JunB blocks FoxO3 binding to atrogin-1 and MuRF-1 promoters and thus reduces protein breakdown. Therefore, JunB is important not only in dividing populations but also in adult muscle, where it is required for the maintenance of muscle size and can induce rapid hypertrophy and block atrophy. PMID:20921137

Renoprotective Effect of Lactoferrin against Chromium-Induced Acute Kidney Injury in Rats: Involvement of IL-18 and IGF-1 Inhibition.

PubMed

Hegazy, Rehab; Salama, Abeer; Mansour, Dina; Hassan, Azza

2016-01-01

Hexavalent chromium (CrVI) is a heavy metal widely used in more than 50 industries. Nephrotoxicity is a major adverse effect of chromium poisoning. The present study investigated the potential renoprotective effect of lactoferrin (Lf) against potassium dichromate (PDC)-induced acute kidney injury (AKI) in rats. Beside, because previous studies suggest that interlukin-18 (IL-18) and insulin-like growth factor-1 (IGF-1) play important roles in promoting kidney damage, the present work aimed to evaluate the involvement of these two cytokines in PDC model of AKI and in the potential renoprotective effect of lactoferrin. Adult male albino Wistar rats were pretreated with Lf (200 mg/kg/day, p.o.) or (300 mg/kg/day, p.o.); the doses that are usually used in the experiment studies, for 14 days followed by a single dose of PDC (15 mg/kg, s.c.). PDC caused significant increase in serum urea, creatinine, and total protein levels. This was accompanied with decreased renal glutathione content, and increased renal malondialdehyde, IL-18, IL-4, nuclear factor kappa B (NFκB), IGF-1, and the phosphorylated form of forkhead box protein O1 (FoxO1) levels. Moreover, normal expression IFN-γ mRNA and enhanced expression of TNF-α mRNA was demonstrated in renal tissues. Histopathological investigations provoked deleterious changes in the renal tissues. Tubular epithelial hyperplasia and apoptosis were demonstrated immunohistochemically by positive proliferating cell nuclear antigen (PCNA), Bax, and Caspase-3 expression, respectively. Pretreatment of rats with Lf in both doses significantly corrected all previously mentioned PDC-induced changes with no significant difference between both doses. In conclusion, the findings of the present study demonstrated the involvement of oxidative stress, inflammatory reactions, tubular hyperplasia and apoptosis in PDC-induced AKI. It suggested a role of IL-18 through stimulation of IL-4-induced inflammatory pathway, and IGF-1 through triggering FoxO1-induced cell proliferation. Moreover, the study revealed that Lf protected the kidney against Cr-induced AKI in rats and significantly showed antioxidant, anti-inflammatory, and anti-proliferative properties with down-regulation of IL-18 and IGF-1.

An anterior signaling center patterns and sizes the anterior neuroectoderm of the sea urchin embryo.

PubMed

Range, Ryan C; Wei, Zheng

2016-05-01

Anterior signaling centers help specify and pattern the early anterior neuroectoderm (ANE) in many deuterostomes. In sea urchin the ANE is restricted to the anterior of the late blastula stage embryo, where it forms a simple neural territory comprising several types of neurons as well as the apical tuft. Here, we show that during early development, the sea urchin ANE territory separates into inner and outer regulatory domains that express the cardinal ANE transcriptional regulators FoxQ2 and Six3, respectively. FoxQ2 drives this patterning process, which is required to eliminate six3 expression from the inner domain and activate the expression of Dkk3 and sFRP1/5, two secreted Wnt modulators. Dkk3 and low expression levels of sFRP1/5 act additively to potentiate the Wnt/JNK signaling pathway governing the positioning of the ANE territory around the anterior pole, whereas high expression levels of sFRP1/5 antagonize Wnt/JNK signaling. sFRP1/5 and Dkk3 levels are rigidly maintained via autorepressive and cross-repressive interactions with Wnt signaling components and additional ANE transcription factors. Together, these data support a model in which FoxQ2 initiates an anterior patterning center that implements correct size and positions of ANE structures. Comparisons of functional and expression studies in sea urchin, hemichordate and chordate embryos reveal striking similarities among deuterostome ANE regulatory networks and the molecular mechanism that positions and defines ANE borders. These data strongly support the idea that the sea urchin embryo uses an ancient anterior patterning system that was present in the common ambulacrarian/chordate ancestor. © 2016. Published by The Company of Biologists Ltd.

Detection of expressional changes induced by intrauterine growth restriction in the developing rat pancreas.

PubMed

Zhang, Lin; Chen, Wei; Dai, Yuee; Zhu, Ziyang; Liu, Qianqi

2016-07-01

Intrauterine growth retardation (IUGR) is a disorder that can result in permanent changes in the physiology and metabolism of the newborn, which increased the risk of disease in adulthood. Evidence supports IUGR as a risk factor for the development of diabetes mellitus, which could reflect changes in pancreas developmental pathways. We sought to characterize the IUGR-induced alterations of the complex pathways of pancreas development in a rat model of IUGR. We analyzed the pancreases of Sprague Dawley rats after inducing IUGR by feeding a maternal low calorie diet from gestational day 1 until term. IUGR altered the pancreatic structure, islet areas, and islet quantities and resulted in abnormal morphological changes during pancreatic development, as determined by HE staining and light microscopy. We identified multiple differentially expressed genes in the pancreas by RT-PCR. The genes of the insulin/FoxO1/Pdx1/MafA signaling pathway were first expressed at embryonic day 14 (E14). The expressions of insulin and MafA increased as the fetus grew while the expressions of FoxO1 and Pdx1 decreased. Compared with the control rats, the expressions of FoxO1, Pdx1, and MafA were lower in the IUGR rats, whereas insulin levels showed no change. Microarray profiling, in combination with quantitative real-time PCR, uncovered a subset of microRNAs that changed in their degree of expression throughout pancreatic development. In conclusion, our data support the hypothesis that IUGR influences the development of the rat pancreas. We also identified new pathways that appear to be programmed by IUGR. © 2016 by the Society for Experimental Biology and Medicine.

A Role for Smoothened during Murine Lens and Cornea Development

PubMed Central

Trogrlic, Lidia; Milevski, Stefan V.; Familari, Mary; Martinez, Gemma; de Iongh, Robb U

2014-01-01

Various studies suggest that Hedgehog (Hh) signalling plays roles in human and zebrafish ocular development. Recent studies (Kerr et al., Invest Ophthalmol Vis Sci. 2012; 53, 3316–30) showed that conditionally activating Hh signals promotes murine lens epithelial cell proliferation and disrupts fibre differentiation. In this study we examined the expression of the Hh pathway and the requirement for the Smoothened gene in murine lens development. Expression of Hh pathway components in developing lens was examined by RT-PCR, immunofluorescence and in situ hybridisation. The requirement of Smo in lens development was determined by conditional loss-of-function mutations, using LeCre and MLR10 Cre transgenic mice. The phenotype of mutant mice was examined by immunofluorescence for various markers of cell cycle, lens and cornea differentiation. Hh pathway components (Ptch1, Smo, Gli2, Gli3) were detected in lens epithelium from E12.5. Gli2 was particularly localised to mitotic nuclei and, at E13.5, Gli3 exhibited a shift from cytosol to nucleus, suggesting distinct roles for these transcription factors. Conditional deletion of Smo, from ∼E12.5 (MLR10 Cre) did not affect ocular development, whereas deletion from ∼E9.5 (LeCre) resulted in lens and corneal defects from E14.5. Mutant lenses were smaller and showed normal expression of p57Kip2, c-Maf, E-cadherin and Pax6, reduced expression of FoxE3 and Ptch1 and decreased nuclear Hes1. There was normal G1-S phase but decreased G2-M phase transition at E16.5 and epithelial cell death from E14.5-E16.5. Mutant corneas were thicker due to aberrant migration of Nrp2+ cells from the extraocular mesenchyme, resulting in delayed corneal endothelial but normal epithelial differentiation. These results indicate the Hh pathway is required during a discrete period (E9.5–E12.5) in lens development to regulate lens epithelial cell proliferation, survival and FoxE3 expression. Defective corneal development occurs secondary to defects in lens and appears to be due to defective migration of peri-ocular Nrp2+ neural crest/mesenchymal cells. PMID:25268479

Cellular homeoproteins, SATB1 and CDP, bind to the unique region between the human cytomegalovirus UL127 and major immediate-early genes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee Jialing; Klase, Zachary; Gao Xiaoqi

An AT-rich region of the human cytomegalovirus (CMV) genome between the UL127 open reading frame and the major immediate-early (MIE) enhancer is referred to as the unique region (UR). It has been shown that the UR represses activation of transcription from the UL127 promoter and functions as a boundary between the divergent UL127 and MIE genes during human CMV infection [Angulo, A., Kerry, D., Huang, H., Borst, E.M., Razinsky, A., Wu, J., Hobom, U., Messerle, M., Ghazal, P., 2000. Identification of a boundary domain adjacent to the potent human cytomegalovirus enhancer that represses transcription of the divergent UL127 promoter. J.more » Virol. 74 (6), 2826-2839; Lundquist, C.A., Meier, J.L., Stinski, M.F., 1999. A strong negative transcriptional regulatory region between the human cytomegalovirus UL127 gene and the major immediate-early enhancer. J. Virol. 73 (11), 9039-9052]. A putative forkhead box-like (FOX-like) site, AAATCAATATT, was identified in the UR and found to play a key role in repression of the UL127 promoter in recombinant virus-infected cells [Lashmit, P.E., Lundquist, C.A., Meier, J.L., Stinski, M.F., 2004. Cellular repressor inhibits human cytomegalovirus transcription from the UL127 promoter. J. Virol. 78 (10), 5113-5123]. However, the cellular factors which associate with the UR and FOX-like region remain to be determined. We reported previously that pancreatic-duodenal homeobox factor-1 (PDX1) bound to a 45-bp element located within the UR [Chao, S.H., Harada, J.N., Hyndman, F., Gao, X., Nelson, C.G., Chanda, S.K., Caldwell, J.S., 2004. PDX1, a Cellular Homeoprotein, Binds to and Regulates the Activity of Human Cytomegalovirus Immediate Early Promoter. J. Biol. Chem. 279 (16), 16111-16120]. Here we demonstrate that two additional cellular homeoproteins, special AT-rich sequence binding protein 1 (SATB1) and CCAAT displacement protein (CDP), bind to the human CMV UR in vitro and in vivo. Furthermore, CDP is identified as a FOX-like binding protein and a repressor of the UL127 promoter, while SATB1 has no effect on UL127 expression. Since CDP is known as a transcription repressor and a nuclear matrix-associated region binding protein, CDP may have a role in the regulation of human CMV transcription.« less

FoxP3+ T regulatory cells in oral lichen planus and its correlation with the distinct clinical appearance of the lesions

PubMed Central

Pereira, Joabe S; Monteiro, Bárbara V; Nonaka, Cassiano F; Silveira, Éricka J; Miguel, Márcia C

2012-01-01

The aim of this study was to evaluate the presence of FoxP3+ cells in oral lichen planus (OLP) and to correlate the findings with clinical and histopathological features of these lesions. The sample consisted of 32 cases of OLP (17 reticular and 15 erosive cases) and 10 cases of inflammatory fibrous hyperplasia (IFH). Clinical examination, histopathological and histomorphometric analysis, and immunohistochemistry (anti-FoxP3 antibody) were performed. Cells were counted in juxtaepithelial and intraepithelial regions of the lesions, and the results are expressed as the mean and range. Most erosive lesions were keratinized and exhibited epithelial atrophy, whereas most reticular lesions were hyperkeratinized. Mean epithelial thickness and mean density of the inflammatory infiltrate were higher in reticular lesions than in erosive OLP. Juxtaepithelial FoxP3+ cells were slightly more frequent in erosive lesions (mean: 1.7 and range: 0–9.4) than in reticular lesions (mean: 1.5 and range: 0–8.3). There was a significant difference in the frequency of these cells between OLP (mean: 1.6 and range: 0–9.4) and IFH (mean: 0.5 and range: 0–1.4) (P < 0.05). The number of intraepithelial FoxP3+ cells was higher in reticular OLP and IFH when compared with erosive lesions. The larger number of juxtaepithelial FoxP3+ cells in OLP compared to IFH might be related to the distinct etiopathogenesis of these lesions. High disease activity or action of the oral microbiota may explain the slightly higher frequency of FoxP3+ cells in erosive lesions. PMID:22804765

FoxP3(+) T regulatory cells in oral lichen planus and its correlation with the distinct clinical appearance of the lesions.

PubMed

Pereira, Joabe S; Monteiro, Bárbara V; Nonaka, Cassiano F; Silveira, Éricka J; Miguel, Márcia C

2012-08-01

The aim of this study was to evaluate the presence of FoxP3(+) cells in oral lichen planus (OLP) and to correlate the findings with clinical and histopathological features of these lesions. The sample consisted of 32 cases of OLP (17 reticular and 15 erosive cases) and 10 cases of inflammatory fibrous hyperplasia (IFH). Clinical examination, histopathological and histomorphometric analysis, and immunohistochemistry (anti-FoxP3 antibody) were performed. Cells were counted in juxtaepithelial and intraepithelial regions of the lesions, and the results are expressed as the mean and range. Most erosive lesions were keratinized and exhibited epithelial atrophy, whereas most reticular lesions were hyperkeratinized. Mean epithelial thickness and mean density of the inflammatory infiltrate were higher in reticular lesions than in erosive OLP. Juxtaepithelial FoxP3(+) cells were slightly more frequent in erosive lesions (mean: 1.7 and range: 0-9.4) than in reticular lesions (mean: 1.5 and range: 0-8.3). There was a significant difference in the frequency of these cells between OLP (mean: 1.6 and range: 0-9.4) and IFH (mean: 0.5 and range: 0-1.4) (P < 0.05). The number of intraepithelial FoxP3(+) cells was higher in reticular OLP and IFH when compared with erosive lesions. The larger number of juxtaepithelial FoxP3(+) cells in OLP compared to IFH might be related to the distinct etiopathogenesis of these lesions. High disease activity or action of the oral microbiota may explain the slightly higher frequency of FoxP3(+) cells in erosive lesions. © 2012 The Authors. International Journal of Experimental Pathology © 2012 International Journal of Experimental Pathology.

FoxO proteins restrain osteoclastogenesis and bone resorption by attenuating H2O2 accumulation

PubMed Central

Bartell, Shoshana M.; Kim, Ha-Neui; Ambrogini, Elena; Han, Li; Iyer, Srividhya; Serra Ucer, S.; Rabinovitch, Peter; Jilka, Robert L.; Weinstein, Robert S.; Zhao, Haibo; O’Brien, Charles A.; Manolagas, Stavros C.; Almeida, Maria

2014-01-01

Besides their cell-damaging effects in the setting of oxidative stress, reactive oxygen species (ROS) play an important role in physiological intracellular signalling by triggering proliferation and survival. FoxO transcription factors counteract ROS generation by upregulating antioxidant enzymes. Here we show that intracellular H2O2 accumulation is a critical and purposeful adaptation for the differentiation and survival of osteoclasts, the bone cells responsible for the resorption of mineralized bone matrix. Using mice with conditional loss or gain of FoxO transcription factor function, or mitochondria-targeted catalase in osteoclasts, we demonstrate this is achieved, at least in part, by downregulating the H2O2-inactivating enzyme catalase. Catalase downregulation results from the repression of the transcriptional activity of FoxO1, 3 and 4 by RANKL, the indispensable signal for the generation of osteoclasts, via an Akt-mediated mechanism. Notably, mitochondria-targeted catalase prevented the loss of bone caused by loss of oestrogens, suggesting that decreasing H2O2 production in mitochondria may represent a rational pharmacotherapeutic approach to diseases with increased bone resorption. PMID:24781012

Foxp1/2/4 regulate endochondral ossification as a suppresser complex

PubMed Central

Zhao, Haixia; Zhou, Wenrong; Yao, Zhengju; Wan, Yong; Cao, Jingjing; Zhang, Lingling; Zhao, Jianzhi; Li, Hanjun; Zhou, Rujiang; Li, Baojie; Wei, Gang; Zhang, Zhenlin; French, Catherine A.; Dekker, Joseph D.; Yang, Yingzi; Fisher, Simon E.; lucker, Haley O.; Guo, Xizhi

2015-01-01

Osteoblast induction and differentiation in developing long bones is dynamically controlled by the opposing action of transcriptional activators and repressors. In contrast to the long list of activators that have been discovered over past decades, the network of repressors is not well-defined. Here we identify the expression of Foxp1/2/4 proteins, comprised of Forkhead-box (Fox) transcription factors of the Foxp subfamily, in both perichondrial skeletal progenitors and proliferating chondrocytes during endochondral ossification. Mice carrying loss-of-function and gain-of-function Foxp mutations had gross defects in appendicular skeleton formation. At the cellular level, over-expression of Foxp1/2/4 in chondroctyes abrogated osteoblast formation and chondrocyte hypertrophy. Conversely, single or compound deficiency of Foxp1/2/4 in skeletal progenitors or chondrocytes resulted in premature osteoblast differentiation in the perichondrium, coupled with impaired proliferation, survival, and hypertrophy of chondrocytes in the growth plate. Foxp1/2/4 and Runx2 proteins interacted in vitro and in vivo, and Foxp1/2/4 repressed Runx2 transactivation function in heterologous cells. This study establishes Foxp1/2/4 proteins as coordinators of osteogenesis and chondrocyte hypertrophy in developing long bones and suggests that a novel transcriptional repressor network involving Foxp1/2/4 may regulate Runx2 during endochondral ossification. PMID:25527076

IL-21 Is an Antitolerogenic Cytokine of the Late-Phase Alloimmune Response

PubMed Central

Petrelli, Alessandra; Carvello, Michele; Vergani, Andrea; Lee, Kang Mi; Tezza, Sara; Du, Ming; Kleffel, Sonja; Chengwen, Liu; Mfarrej, Bechara G.; Hwu, Patrick; Secchi, Antonio; Leonard, Warren J.; Young, Deborah; Sayegh, Mohamed H.; Markmann, James F.; Zajac, Allan J.; Fiorina, Paolo

2011-01-01

OBJECTIVE Interleukin-21 (IL-21) is a proinflammatory cytokine that has been shown to affect Treg/Teff balance. However, the mechanism by which IL-21 orchestrates alloimmune response and interplays with Tregs is still unclear. RESEARCH DESIGN AND METHODS The interplay between IL-21/IL-21R signaling, FoxP3 expression, and Treg survival and function was evaluated in vitro in immunologically relevant assays and in vivo in allogenic and autoimmune models of islet transplantation. RESULTS IL-21R expression decreases on T cells and B cells in vitro and increases in the graft in vivo, while IL-21 levels increase in vitro and in vivo during anti-CD3/anti-CD28 stimulation/allostimulation in the late phase of the alloimmune response. In vitro, IL-21/IL-21R signaling (by using rmIL-21 or genetically modified CD4+ T cells [IL-21 pOrf plasmid–treated or hIL-21-Tg mice]) enhances the T-cell response during anti-CD3/anti-CD28 stimulation/allostimulation, prevents Treg generation, inhibits Treg function, induces Treg apoptosis, and reduces FoxP3 and FoxP3-dependent gene transcripts without affecting FoxP3 methylation status. In vivo targeting of IL-21/IL-21R expands intragraft and peripheral Tregs, promotes Treg neogenesis, and regulates the antidonor immune response, whereas IL-21/IL-21R signaling in Doxa-inducible ROSA-rtTA-IL-21-Tg mice expands Teffs and FoxP3− cells. Treatment with a combination of mIL-21R.Fc and CTLA4-Ig (an inhibitor of the early alloimmune response) leads to robust graft tolerance in a purely alloimmune setting and prolonged islet graft survival in NOD mice. CONCLUSIONS IL-21 interferes with different checkpoints of the FoxP3 Treg chain in the late phase of alloimmune response and, thus, acts as an antitolerogenic cytokine. Blockade of the IL-21/IL-21R pathway could be a precondition for tolerogenic protocols in transplantation. PMID:22013017

An integrated approach for identifying priority contaminant in the Great Lakes Basin - Investigations in the Lower Green Bay/Fox River and Milwaukee Estuary areas of concern.

PubMed

Li, Shibin; Villeneuve, Daniel L; Berninger, Jason P; Blackwell, Brett R; Cavallin, Jenna E; Hughes, Megan N; Jensen, Kathleen M; Jorgenson, Zachary; Kahl, Michael D; Schroeder, Anthony L; Stevens, Kyle E; Thomas, Linnea M; Weberg, Matthew A; Ankley, Gerald T

2017-02-01

Environmental assessment of complex mixtures typically requires integration of chemical and biological measurements. This study demonstrates the use of a combination of instrumental chemical analyses, effects-based monitoring, and bio-effects prediction approaches to help identify potential hazards and priority contaminants in two Great Lakes Areas of Concern (AOCs), the Lower Green Bay/Fox River located near Green Bay, WI, USA and the Milwaukee Estuary, located near Milwaukee, WI, USA. Fathead minnows were caged at four sites within each AOC (eight sites total). Following 4d of in situ exposure, tissues and biofluids were sampled and used for targeted biological effects analyses. Additionally, 4d composite water samples were collected concurrently at each caged fish site and analyzed for 132 analytes as well as evaluated for total estrogenic and androgenic activity using cell-based bioassays. Of the analytes examined, 75 were detected in composite samples from at least one site. Based on multiple analyses, one site in the East River and another site near a paper mill discharge in the Lower Green Bay/Fox River AOC, were prioritized due to their estrogenic and androgenic activity, respectively. The water samples from other sites generally did not exhibit significant estrogenic or androgenic activity, nor was there evidence for endocrine disruption in the fish exposed at these sites as indicated by the lack of alterations in ex vivo steroid production, circulating steroid concentrations, or vitellogenin mRNA expression in males. Induction of hepatic cyp1a mRNA expression was detected at several sites, suggesting the presence of chemicals that activate the aryl hydrocarbon receptor. To expand the scope beyond targeted investigation of endpoints selected a priori, several bio-effects prediction approaches were employed to identify other potentially disturbed biological pathways and related chemical constituents that may warrant future monitoring at these sites. For example, several chemicals such as diethylphthalate and naphthalene, and genes and related pathways, such as cholinergic receptor muscarinic 3 (CHRM3), estrogen receptor alpha1 (esr1), chemokine ligand 10 protein (CXCL10), tumor protein p53 (p53), and monoamine oxidase B (Maob), were identified as candidates for future assessments at these AOCs. Overall, this study demonstrates that a better prioritization of contaminants and associated hazards can be achieved through integrated evaluation of multiple lines of evidence. Such prioritization can guide more comprehensive follow-up risk assessment efforts. Copyright © 2016 Elsevier B.V. All rights reserved.

Tumor-associated macrophages recruit CCR6+ regulatory T cells and promote the development of colorectal cancer via enhancing CCL20 production in mice.

PubMed

Liu, Jinlin; Zhang, Ning; Li, Qun; Zhang, Weiwei; Ke, Fang; Leng, Qibin; Wang, Hong; Chen, Jinfei; Wang, Honglin

2011-04-29

Tumor-associated macrophages (TAMs) remodel the colorectal cancer (CRC) microenvironment. Yet, findings on the role of TAMs in CRC seem to be contradictory compared with other cancers. FoxP3(+) regulatory T (Treg)-cells dominantly infiltrate CRC. However, the underlying molecular mechanism in which TAMs may contribute to the trafficking of Treg-cells to the tumor mass remains unknown. CRC was either induced by N-methyl-N-nitrosourea (MNU) and H. pylori or established by subcutaneous injection of mouse colorectal tumor cell line (CMT93) in mice. CMT93 cells were co-cultured with primary macrophages in a transwell apparatus. Recruitment of FoxP3 green fluorescence protein positive (FoxP3(GFP+)) Treg-cells was assessed using the IVIS Imaging System or immunofluorescence staining. A role for macrophages in trafficking of Treg-cells and in the development of CRC was investigated in CD11b diphtheria toxin receptor (CD11b-DTR) transgenic C57BL/6J mice in which macrophages can be selectively depleted. Treg-cells remarkably infiltrated solid tumor, and predominantly expressed the homing chemokine receptor (CCR) 6 in the induced CRC model. Both CMT93 cancer cells and macrophages produced a large amount of CCL20, the sole ligand of CCR6 in vitro and in vivo. Injection of recombinant mouse CCL20 into tumor sites promoted its development with a marked recruitment of Treg-cells in the graft CRC model. Conditional macrophage ablation decreased CCL20 levels, blocked Treg-cell recruitment and inhibited tumor growth in CD11b-DTR mice grafted with CMT93. TAMs recruit CCR6(+) Treg-cells to tumor mass and promote its development via enhancing the production of CCL20 in a CRC mouse model.

Maintaining HNF6 expression prevents AdHNF3beta-mediated decrease in hepatic levels of Glut-2 and glycogen.

PubMed

Tan, Yongjun; Adami, Guy; Costa, Robert H

2002-04-01

The hepatocyte nuclear factor 3 (HNF-3) proteins are members of the Forkhead Box (Fox) family of transcription factors that play important roles in regulating expression of genes involved in cellular proliferation, differentiation, and metabolic homeostasis. In previous studies we increased liver expression of HNF-3beta by using either transgenic mice (transthyretin HNF-3beta) or recombinant adenovirus infection (AdHNF3beta), and observed diminished hepatic levels of glycogen, and glucose transporter 2 (Glut-2), as well as the HNF-6, HNF-3, HNF-1alpha, HNF-4alpha, and C/EBPalpha transcription factors. We conducted the present study to determine whether maintaining HNF-6 protein expression during AdHNF3beta infection prevents reduction of hepatic levels of glycogen and the earlier-mentioned genes. Here, we show that AdHNF3beta- and AdHNF6-infected mouse liver displayed increased hepatic levels of glycogen, Glut-2, HNF-3gamma, HNF-1alpha, and HNF-4alpha at 2 and 3 days postinfection (PI). Furthermore, restoration of hepatic glycogen levels after AdHNF3beta and AdHNF6 coinfection was associated with increased Glut-2 expression. AdHNF6 infection alone caused a 2-fold increase in hepatic Glut-2 levels, suggesting that HNF 6 stimulates in vivo transcription of the Glut-2 gene. DNA binding assays showed that only recombinant HNF-6 protein, but not the HNF-3 proteins, binds to the mouse -185 to -144 bp Glut-2 promoter sequences. Cotransfection assays in human hepatoma (HepG2) cells with either HNF-3 or HNF-6 expression vectors show that only HNF-6 provided significant transcriptional activation of the Glut-2 promoter. In conclusion, these studies show that the hepatic Glut-2 promoter is a direct target for HNF-6 transcriptional activation.

Ovarian function in mice results in abrogated skeletal muscle PPARdelta and FoxO1-mediated gene expression

USDA-ARS?s Scientific Manuscript database

Menopause, the age-related loss of ovarian hormone production, promotes increased adiposity and associated metabolic pathology, but molecular mechanisms remain unclear. We previously reported that estrogen increases skeletal muscle PPARDelta expression in vivo, and transgenic mice overexpressing mus...

IGF-II-mediated downregulation of peroxisome proliferator-activated receptor-γ coactivator-1α in myoblast cells involves PI3K/Akt/FoxO1 signaling pathway.

PubMed

Mu, Xiaoyu; Qi, Weihong; Liu, Yunzhang; Zhou, Jianfeng; Li, Yun; Rong, Xiaozhi; Lu, Ling

2017-08-01

Insulin-like growth factor II (IGF-II) can stimulate myogenesis and is critically involved in skeletal muscle differentiation. The presence of negative regulators of this process, however, is not well explored. Here, we showed that in myoblast cells, IGF-II negatively regulated peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) mRNA expression, while constitutive expression of PGC-1α induced myoblast differentiation. These results suggest that the negative regulation of PGC-1α by IGF-II may act as a negative feedback mechanism in IGF-II-induced myogenic differentiation. Reporter assays demonstrated that IGF-II suppresses the basal PGC-1α promoter activity. Blocking the IGF-II signaling pathway increased the endogenous PGC-1α levels. In addition, pharmacological inhibition of PI3 kinase activity prevented the downregulation of PGC-1α but the activation of mTOR was not required for this process. Importantly, further analysis showed that forkhead transcription factor FoxO1 contributes to mediating the effects of IGF-II on PGC-1 promoter activity. These findings indicate that IGF-II reduces PGC-1α expression in skeletal muscle cells through a mechanism involving PI3K-Akt-FoxO1 but not p38 MAPK or Erk1/2 MAPK pathways.

Aberrant muscle antigen exposure in mice is sufficient to cause myositis in a Treg cell-deficient milieu.

PubMed

Young, Nicholas A; Sharma, Rahul; Friedman, Alexandra K; Kaffenberger, Benjamin H; Bolon, Brad; Jarjour, Wael N

2013-12-01

Myositis is associated with muscle-targeted inflammation and is observed in some Treg cell-deficient mouse models. Because an autoimmune pathogenesis has been strongly implicated, the aim of this study was to investigate the hypothesis that abnormal exposure to muscle antigens, as observed in muscle injury, can induce autoimmune-mediated myositis in susceptible hosts. FoxP3 mutant (scurfy) mice were mated to synaptotagmin VII (Syt VII) mutant mice, which resulted in a new mouse strain that combines impaired membrane resealing with Treg cell deficiency. Lymphocyte preparations from double-mutant mice were adoptively transferred intraperitoneally, with or without purified Treg cells, into recombination-activating gene 1 (RAG-1)-null recipients. Lymph node cells from mice with the FoxP3 mutation were transferred into RAG-1-null mice either 1) intraperitoneally in conjunction with muscle homogenate or purified myosin protein or 2) intramuscularly with or without cotransfer of purified Treg cells. FoxP3-deficient mouse lymph node cells transferred in conjunction with myosin protein or muscle homogenate induced robust skeletal muscle inflammation. The infiltrates consisted predominantly of CD4+ and CD8+ T cells, a limited number of macrophages, and no B cells. Significant inflammation was also seen in similar experiments using lymph node cells from FoxP3/Syt VII double-mutant mice but was absent in experiments using adoptive transfer of FoxP3 mutant mouse cells alone. The cotransfer of Treg cells completely suppressed myositis. These data, derived from a new, reproducible model, demonstrate the critical roles of Treg cell deficiency and aberrant muscle antigen exposure in the priming of autoreactive cells to induce myositis. This mouse system has multifaceted potential for examining the interplay in vivo between tissue injury and autoimmunity. © 2013 The Authors. Arthritis & Rheumatism is published by Wiley Periodicals, Inc. on behalf of the American College of Rheumatology.

Histone Deacetylase Inhibition Promotes Osteoblast Maturation by Altering the Histone H4 Epigenome and Reduces Akt Phosphorylation*

PubMed Central

Dudakovic, Amel; Evans, Jared M.; Li, Ying; Middha, Sumit; McGee-Lawrence, Meghan E.; van Wijnen, Andre J.; Westendorf, Jennifer J.

2013-01-01

Bone has remarkable regenerative capacity, but this ability diminishes during aging. Histone deacetylase inhibitors (HDIs) promote terminal osteoblast differentiation and extracellular matrix production in culture. The epigenetic events altered by HDIs in osteoblasts may hold clues for the development of new anabolic treatments for osteoporosis and other conditions of low bone mass. To assess how HDIs affect the epigenome of committed osteoblasts, MC3T3 cells were treated with suberoylanilide hydroxamic acid (SAHA) and subjected to microarray gene expression profiling and high-throughput ChIP-Seq analysis. As expected, SAHA induced differentiation and matrix calcification of osteoblasts in vitro. ChIP-Seq analysis revealed that SAHA increased histone H4 acetylation genome-wide and in differentially regulated genes, except for the 500 bp upstream of transcriptional start sites. Pathway analysis indicated that SAHA increased the expression of insulin signaling modulators, including Slc9a3r1. SAHA decreased phosphorylation of insulin receptor β, Akt, and the Akt substrate FoxO1, resulting in FoxO1 stabilization. Thus, SAHA induces genome-wide H4 acetylation and modulates the insulin/Akt/FoxO1 signaling axis, whereas it promotes terminal osteoblast differentiation in vitro. PMID:23940046

Soy Leaf Extract Containing Kaempferol Glycosides and Pheophorbides Improves Glucose Homeostasis by Enhancing Pancreatic β-Cell Function and Suppressing Hepatic Lipid Accumulation in db/db Mice.

PubMed

Li, Hua; Ji, Hyeon-Seon; Kang, Ji-Hyun; Shin, Dong-Ha; Park, Ho-Yong; Choi, Myung-Sook; Lee, Chul-Ho; Lee, In-Kyung; Yun, Bong-Sik; Jeong, Tae-Sook

2015-08-19

This study investigated the molecular mechanisms underlying the antidiabetic effect of an ethanol extract of soy leaves (ESL) in db/db mice. Control groups (db/+ and db/db) were fed a normal diet (ND), whereas the db/db-ESL group was fed ND with 1% ESL for 8 weeks. Dietary ESL improved glucose tolerance and lowered plasma glucose, glycated hemoglobin, HOMA-IR, and triglyceride levels. The pancreatic insulin content of the db/db-ESL group was significantly greater than that of the db/db group. ESL supplementation altered pancreatic IRS1, IRS2, Pdx1, Ngn3, Pax4, Ins1, Ins2, and FoxO1 expression. Furthermore, ESL suppressed lipid accumulation and increased glucokinase activity in the liver. ESL primarily contained kaempferol glycosides and pheophorbides. Kaempferol, an aglycone of kaempferol glycosides, improved β-cell proliferation through IRS2-related FoxO1 signaling, whereas pheophorbide a, a product of chlorophyll breakdown, improved insulin secretion and β-cell proliferation through IRS1-related signaling with protein kinase A in MIN6 cells. ESL effectively regulates glucose homeostasis by enhancing IRS-mediated β-cell insulin signaling and suppressing SREBP-1-mediated hepatic lipid accumulation in db/db mice.

Leucine supplementation increases SIRT1 expression and prevents mitochondrial dysfunction and metabolic disorders in high-fat diet-induced obese mice.

PubMed

Li, Hongliang; Xu, Mingjiang; Lee, Jiyeon; He, Chaoyong; Xie, Zhonglin

2012-11-15

Leucine supplementation has been shown to prevent high-fat diet (HFD)-induced obesity, hyperglycemia, and dyslipidemia in animal models, but the underlying mechanisms are not fully understood. Recent studies suggest that activation of Sirtuin 1 (SIRT1) is an important mechanism to maintain energy and metabolic homeostasis. We therefore examined the involvement of SIRT1 in leucine supplementation-prevented obesity and insulin resistance. To accomplish this goal, male C57BL/6J mice were fed normal diet or HFD, supplemented with or without leucine. After 2 mo of treatment, alterations in SIRT1 expression, insulin signaling, and energy metabolism were analyzed. Eight weeks of HFD induced obesity, fatty liver, mitochondrial dysfunction, hyperglycemia, and insulin resistance in mice. Addition of leucine to HFD correlated with increased expression of SIRT1 and NAMPT (nicotinamide phosphoribosyltransferase) as well as higher intracellular NAD(+) levels, which decreased acetylation of peroxisome proliferator-activated receptor-γ coactivator 1α (PGC1α) and forkhead box O1 (FoxO1). The deacetylation of PGC1α may contribute to upregulation of genes controlling mitochondrial biogenesis and fatty acid oxidation, thereby improving mitochondrial function and preventing HFD-induced obesity in mice. Moreover, decreased acetylation of FoxO1 was accompanied by decreased expression of pseudokinase tribble 3 (TRB3) and reduced the association between TRB3 and Akt, which enhanced insulin sensitivity and improved glucose metabolism. Finally, transfection of dominant negative AMPK prevented activation of SIRT1 signaling in HFD-Leu mice. These data suggest that increased expression of SIRT1 after leucine supplementation may lead to reduced acetylation of PGC1α and FoxO1, which is associated with attenuation of HFD-induced mitochondrial dysfunction, insulin resistance, and obesity.

Leucine supplementation increases SIRT1 expression and prevents mitochondrial dysfunction and metabolic disorders in high-fat diet-induced obese mice

PubMed Central

Li, Hongliang; Xu, Mingjiang; Lee, Jiyeon; He, Chaoyong

2012-01-01

Leucine supplementation has been shown to prevent high-fat diet (HFD)-induced obesity, hyperglycemia, and dyslipidemia in animal models, but the underlying mechanisms are not fully understood. Recent studies suggest that activation of Sirtuin 1 (SIRT1) is an important mechanism to maintain energy and metabolic homeostasis. We therefore examined the involvement of SIRT1 in leucine supplementation-prevented obesity and insulin resistance. To accomplish this goal, male C57BL/6J mice were fed normal diet or HFD, supplemented with or without leucine. After 2 mo of treatment, alterations in SIRT1 expression, insulin signaling, and energy metabolism were analyzed. Eight weeks of HFD induced obesity, fatty liver, mitochondrial dysfunction, hyperglycemia, and insulin resistance in mice. Addition of leucine to HFD correlated with increased expression of SIRT1 and NAMPT (nicotinamide phosphoribosyltransferase) as well as higher intracellular NAD+ levels, which decreased acetylation of peroxisome proliferator-activated receptor-γ coactivator 1α (PGC1α) and forkhead box O1 (FoxO1). The deacetylation of PGC1α may contribute to upregulation of genes controlling mitochondrial biogenesis and fatty acid oxidation, thereby improving mitochondrial function and preventing HFD-induced obesity in mice. Moreover, decreased acetylation of FoxO1 was accompanied by decreased expression of pseudokinase tribble 3 (TRB3) and reduced the association between TRB3 and Akt, which enhanced insulin sensitivity and improved glucose metabolism. Finally, transfection of dominant negative AMPK prevented activation of SIRT1 signaling in HFD-Leu mice. These data suggest that increased expression of SIRT1 after leucine supplementation may lead to reduced acetylation of PGC1α and FoxO1, which is associated with attenuation of HFD-induced mitochondrial dysfunction, insulin resistance, and obesity. PMID:22967499

FOX: A Fault-Oblivious Extreme-Scale Execution Environment Boston University Final Report Project Number: DE-SC0005365

DOE Office of Scientific and Technical Information (OSTI.GOV)

Appavoo, Jonathan

Exascale computing systems will provide a thousand-fold increase in parallelism and a proportional increase in failure rate relative to today's machines. Systems software for exascale machines must provide the infrastructure to support existing applications while simultaneously enabling efficient execution of new programming models that naturally express dynamic, adaptive, irregular computation; coupled simulations; and massive data analysis in a highly unreliable hardware environment with billions of threads of execution. The FOX project explored systems software and runtime support for a new approach to the data and work distribution for fault oblivious application execution. Our major OS work at Boston University focusedmore » on developing a new light-weight operating systems model that provides an appropriate context for both multi-core and multi-node application development. This work is discussed in section 1. Early on in the FOX project BU developed infrastructure for prototyping dynamic HPC environments in which the sets of nodes that an application is run on can be dynamically grown or shrunk. This work was an extension of the Kittyhawk project and is discussed in section 2. Section 3 documents the publications and software repositories that we have produced. To put our work in context of the complete FOX project contribution we include in section 4 an extended version of a paper that documents the complete work of the FOX team.« less

X-chromosome-counting mechanisms that determine nematode sex.

PubMed

Nicoll, M; Akerib, C C; Meyer, B J

1997-07-10

Sex is determined in Caenorhabditis elegans by an X-chromosome-counting mechanism that reliably distinguishes the twofold difference in X-chromosome dose between males (1X) and hermaphrodites (2X). This small quantitative difference is translated into the 'on/off' response of the target gene, xol-1, a switch that specifies the male fate when active and the hermaphrodite fate when inactive. Specific regions of X contain counted signal elements whose combined dose sets the activity of xol-1. Here we ascribe the dose effects of one region to a discrete, protein-encoding gene, fox-1. We demonstrate that the dose-sensitive signal elements on chromosome X control xol-1 through two different molecular mechanisms. One involves the transcriptional repression of xol-1 in XX animals. The other uses the putative RNA-binding protein encoded by fox-1 to reduce the level of xol-1 protein. These two mechanisms of repression act together to ensure the fidelity of the X-chromosome counting process.

The Living Eye “Disarms” Uncommitted Autoreactive T Cells by Converting Them to FoxP3+ Regulatory Cells Following Local Antigen Recognition

PubMed Central

Zhou, Ru; Horai, Reiko; Silver, Phyllis B; Mattapallil, Mary J; Zárate-Bladés, Carlos R; Chong, Wai Po; Chen, Jun; Rigden, Rachael C; Villasmil, Rafael; Caspi, Rachel R

2011-01-01

Immune privilege is used by the eye, brain, reproductive organs and gut to preserve structural and functional integrity in the face of inflammation. The eye is arguably the most vulnerable, and therefore also the most “privileged” of tissues, but paradoxically, remains subject to destructive autoimmunity. It has been proposed, although never proven in vivo, that the eye can induce T regulatory cells (Tregs) locally. Using FoxP3-GFP reporter mice expressing a retina-specific T cell receptor, we now show that uncommitted T cells rapidly convert in the living eye to FoxP3+ Tregs in a process involving retinal antigen recognition, de novo FoxP3 induction and proliferation. This takes place within the ocular tissue and is supported by retinoic acid, which is normally present in the eye due to its function in the chemistry of vision. Non-converted T cells showed evidence of priming, but appeared restricted from expressing effector function in the eye. Preexisting ocular inflammation impeded conversion of uncommitted T cells into Tregs. Importantly, retina-specific T cells primed in vivo before introduction into the eye were resistant to Treg conversion in the ocular environment, and instead caused severe uveitis. Thus, uncommitted T cells can be disarmed, but immune privilege is unable to protect from uveitogenic T cells that have acquired effector function prior to entering the eye. These findings shed new light on the phenomenon of immune privilege and on its role, as well as its limitations, in actively controlling immune responses in the tissue. PMID:22238462

VE-Cadherin–Mediated Epigenetic Regulation of Endothelial Gene Expression

PubMed Central

Morini, Marco F.; Giampietro, Costanza; Corada, Monica; Pisati, Federica; Lavarone, Elisa; Cunha, Sara I.; Conze, Lei L.; O’Reilly, Nicola; Joshi, Dhira; Kjaer, Svend; George, Roger; Nye, Emma; Ma, Anqi; Jin, Jian; Mitter, Richard; Lupia, Michela; Cavallaro, Ugo; Pasini, Diego; Calado, Dinis P.

2018-01-01

Rationale: The mechanistic foundation of vascular maturation is still largely unknown. Several human pathologies are characterized by deregulated angiogenesis and unstable blood vessels. Solid tumors, for instance, get their nourishment from newly formed structurally abnormal vessels which present wide and irregular interendothelial junctions. Expression and clustering of the main endothelial-specific adherens junction protein, VEC (vascular endothelial cadherin), upregulate genes with key roles in endothelial differentiation and stability. Objective: We aim at understanding the molecular mechanisms through which VEC triggers the expression of a set of genes involved in endothelial differentiation and vascular stabilization. Methods and Results: We compared a VEC-null cell line with the same line reconstituted with VEC wild-type cDNA. VEC expression and clustering upregulated endothelial-specific genes with key roles in vascular stabilization including claudin-5, vascular endothelial-protein tyrosine phosphatase (VE-PTP), and von Willebrand factor (vWf). Mechanistically, VEC exerts this effect by inhibiting polycomb protein activity on the specific gene promoters. This is achieved by preventing nuclear translocation of FoxO1 (Forkhead box protein O1) and β-catenin, which contribute to PRC2 (polycomb repressive complex-2) binding to promoter regions of claudin-5, VE-PTP, and vWf. VEC/β-catenin complex also sequesters a core subunit of PRC2 (Ezh2 [enhancer of zeste homolog 2]) at the cell membrane, preventing its nuclear translocation. Inhibition of Ezh2/VEC association increases Ezh2 recruitment to claudin-5, VE-PTP, and vWf promoters, causing gene downregulation. RNA sequencing comparison of VEC-null and VEC-positive cells suggested a more general role of VEC in activating endothelial genes and triggering a vascular stability-related gene expression program. In pathological angiogenesis of human ovarian carcinomas, reduced VEC expression paralleled decreased levels of claudin-5 and VE-PTP. Conclusions: These data extend the knowledge of polycomb-mediated regulation of gene expression to endothelial cell differentiation and vessel maturation. The identified mechanism opens novel therapeutic opportunities to modulate endothelial gene expression and induce vascular normalization through pharmacological inhibition of the polycomb-mediated repression system. PMID:29233846

VE-Cadherin-Mediated Epigenetic Regulation of Endothelial Gene Expression.

PubMed

Morini, Marco F; Giampietro, Costanza; Corada, Monica; Pisati, Federica; Lavarone, Elisa; Cunha, Sara I; Conze, Lei L; O'Reilly, Nicola; Joshi, Dhira; Kjaer, Svend; George, Roger; Nye, Emma; Ma, Anqi; Jin, Jian; Mitter, Richard; Lupia, Michela; Cavallaro, Ugo; Pasini, Diego; Calado, Dinis P; Dejana, Elisabetta; Taddei, Andrea

2018-01-19

The mechanistic foundation of vascular maturation is still largely unknown. Several human pathologies are characterized by deregulated angiogenesis and unstable blood vessels. Solid tumors, for instance, get their nourishment from newly formed structurally abnormal vessels which present wide and irregular interendothelial junctions. Expression and clustering of the main endothelial-specific adherens junction protein, VEC (vascular endothelial cadherin), upregulate genes with key roles in endothelial differentiation and stability. We aim at understanding the molecular mechanisms through which VEC triggers the expression of a set of genes involved in endothelial differentiation and vascular stabilization. We compared a VEC-null cell line with the same line reconstituted with VEC wild-type cDNA. VEC expression and clustering upregulated endothelial-specific genes with key roles in vascular stabilization including claudin-5 , vascular endothelial-protein tyrosine phosphatase ( VE-PTP ), and von Willebrand factor ( vWf ). Mechanistically, VEC exerts this effect by inhibiting polycomb protein activity on the specific gene promoters. This is achieved by preventing nuclear translocation of FoxO1 (Forkhead box protein O1) and β-catenin, which contribute to PRC2 (polycomb repressive complex-2) binding to promoter regions of claudin-5 , VE-PTP , and vWf . VEC/β-catenin complex also sequesters a core subunit of PRC2 (Ezh2 [enhancer of zeste homolog 2]) at the cell membrane, preventing its nuclear translocation. Inhibition of Ezh2/VEC association increases Ezh2 recruitment to claudin-5 , VE-PTP , and vWf promoters, causing gene downregulation. RNA sequencing comparison of VEC-null and VEC-positive cells suggested a more general role of VEC in activating endothelial genes and triggering a vascular stability-related gene expression program. In pathological angiogenesis of human ovarian carcinomas, reduced VEC expression paralleled decreased levels of claudin-5 and VE-PTP. These data extend the knowledge of polycomb-mediated regulation of gene expression to endothelial cell differentiation and vessel maturation. The identified mechanism opens novel therapeutic opportunities to modulate endothelial gene expression and induce vascular normalization through pharmacological inhibition of the polycomb-mediated repression system. © 2017 The Authors.

The Polyunsaturated Fatty Acids Arachidonic Acid and Docosahexaenoic Acid Induce Mouse Dendritic Cells Maturation but Reduce T-Cell Responses In Vitro

PubMed Central

Carlsson, Johan A.; Wold, Agnes E.; Sandberg, Ann-Sofie; Östman, Sofia M.

2015-01-01

Long-chain polyunsaturated fatty acids (PUFAs) might regulate T-cell activation and lineage commitment. Here, we measured the effects of omega-3 (n-3), n-6 and n-9 fatty acids on the interaction between dendritic cells (DCs) and naïve T cells. Spleen DCs from BALB/c mice were cultured in vitro with ovalbumin (OVA) with 50 μM fatty acids; α-linolenic acid, arachidonic acid (AA), eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), linoleic acid or oleic acid and thereafter OVA-specific DO11.10 T cells were added to the cultures. Fatty acids were taken up by the DCs, as shown by gas chromatography analysis. After culture with arachidonic acid or DHA CD11c+ CD11b+ and CD11c+ CD11bneg DCs expressed more CD40, CD80, CD83, CD86 and PDL-1, while IAd remained unchanged. However, fewer T cells co-cultured with these DCs proliferated (CellTrace Violetlow) and expressed CD69 or CD25, while more were necrotic (7AAD+). We noted an increased proportion of T cells with a regulatory T cell (Treg) phenotype, i.e., when gating on CD4+ FoxP3+ CTLA-4+, CD4+ FoxP3+ Helios+ or CD4+ FoxP3+ PD-1+, in co-cultures with arachidonic acid- or DHA-primed DCs relative to control cultures. The proportion of putative Tregs was inversely correlated to T-cell proliferation, indicating a suppressive function of these cells. With arachidonic acid DCs produced higher levels of prostaglandin E2 while T cells produced lower amounts of IL-10 and IFNγ. In conclusion arachidonic acid and DHA induced up-regulation of activation markers on DCs. However arachidonic acid- and DHA-primed DCs reduced T-cell proliferation and increased the proportion of T cells expressing FoxP3, indicating that these fatty acids can promote induction of regulatory T cells. PMID:26619195

Functional Characterization of the FoxE Iron Oxidoreductase from the Photoferrotroph Rhodobacter ferrooxidans SW2*

PubMed Central

Saraiva, Ivo H.; Newman, Dianne K.; Louro, Ricardo O.

2012-01-01

Photoferrotrophy is presumed to be an ancient type of photosynthetic metabolism in which bacteria use the reducing power of ferrous iron to drive carbon fixation. In this work the putative iron oxidoreductase of the photoferrotroph Rhodobacter ferrooxidans SW2 was cloned, purified, and characterized for the first time. This protein, FoxE, was characterized using spectroscopic, thermodynamic, and kinetic techniques. It is a c-type cytochrome that forms a trimer or tetramer in solution; the two hemes of each monomer are hexacoordinated by histidine and methionine. The hemes have positive reduction potentials that allow downhill electron transfer from many geochemically relevant ferrous iron forms to the photosynthetic reaction center. The reduction potentials of the hemes are different and are cross-assigned to fast and slow kinetic phases of ferrous iron oxidation in vitro. Lower reactivity was observed at high pH and may contribute to prevent ferric iron precipitation inside or at the surface of the cell. These results help fill in the molecular details of a metabolic process that likely contributed to the deposition of precambrian banded iron formations, globally important sedimentary rocks that are found on every continent today. PMID:22661703

Transcriptional analysis of liver from chickens with fast (meat bird), moderate (F1 layer x meat bird cross) and low (layer bird) growth potential.

PubMed

Willson, Nicky-Lee; Forder, Rebecca E A; Tearle, Rick; Williams, John L; Hughes, Robert J; Nattrass, Greg S; Hynd, Philip I

2018-05-02

Divergent selection for meat and egg production in poultry has resulted in strains of birds differing widely in traits related to these products. Modern strains of meat birds can reach live weights of 2 kg in 35 d, while layer strains are now capable of producing more than 300 eggs per annum but grow slowly. In this study, RNA-Seq was used to investigate hepatic gene expression between three groups of birds with large differences in growth potential; meat bird, layer strain as well as an F1 layer x meat bird. The objective was to identify differentially expressed (DE) genes between all three strains to elucidate biological factors underpinning variations in growth performance. RNA-Seq analysis was carried out on total RNA extracted from the liver of meat bird (n = 6), F1 layer x meat bird cross (n = 6) and layer strain (n = 6), males. Differential expression of genes were considered significant at P < 0.05, and a false discovery rate of < 0.05, with any fold change considered. In total, 6278 genes were found to be DE with 5832 DE between meat birds and layers (19%), 2935 DE between meat birds and the cross (9.6%) and 493 DE between the cross and layers (1.6%). Comparisons between the three groups identified 155 significant DE genes. Gene ontology (GO) enrichment and Kyoto Encyclopaedia of Genes and Genomes (KEGG) pathway analysis of the 155 DE genes showed the FoxO signalling pathway was most enriched (P = 0.001), including genes related to cell cycle regulation and insulin signalling. Significant GO terms included 'positive regulation of glucose import' and 'cellular response to oxidative stress', which is also consistent with FoxOs regulation of glucose metabolism. There were high correlations between FoxO pathway genes and bodyweight, as well as genes related to glycolysis and bodyweight. This study revealed large transcriptome differences between meat and layer birds. There was significant evidence implicating the FoxO signalling pathway (via cell cycle regulation and altered metabolism) as an active driver of growth variations in chicken. Functional analysis of the FoxO genes is required to understand how they regulate growth and egg production.

Generation of Tioman virus nucleocapsid-like particles in yeast Saccharomyces cerevisiae.

PubMed

Petraityte, Rasa; Tamosiunas, Paulius L; Juozapaitis, Mindaugas; Zvirbliene, Aurelija; Sasnauskas, Kestutis; Shiell, Brian; Russell, Gail; Bingham, John; Michalski, Wojtek P

2009-10-01

Tioman virus (TioV) was isolated from a number of pooled urine samples of Tioman Island flying foxes (Pteropus hypomelanus) during the search for the reservoir host of Nipah virus. Studies have established TioV as a new virus in the family Paramyxoviridae. This novel paramyxovirus is antigenically related to Menangle virus that was isolated in Australia in 1997 during disease outbreak in pigs. TioV causes mild disease in pigs and has a predilection for lymphoid tissues. Recent serosurvey showed that 1.8% of Tioman Islanders had neutralizing antibodies against TioV, indicating probable past infection. For the development of convenient serological tests for this virus, recombinant TioV nucleocapsid (N) protein was expressed in the yeast Saccharomyces cerevisiae. High yields of recombinant TioV N protein were obtained. Electron microscopy demonstrated that purified recombinant N protein self-assembled into nucleocapsid-like particles which were identical in density and morphology to authentic nucleocapsids from paramyxovirus-infected cells. Different size nucleocapsid-like particles were stable and readily purified by CsCl gradient ultracentrifugation. Polyclonal sera raised in rabbits after immunization with recombinant TioV N protein reacted reliably with TioV infected tissues in immunohistochemistry tests. It confirmed that the antigenic properties of yeast derived TioV N protein are identical to authentic viral protein.

Evaluation of in situ expression of effector and regulatory cytokines, TLR, galectins and matrix metalloproteinases in oral manifestations of paracoccidioidomycosis.

PubMed

de Araújo, Marcelo Sivieri; Alves, Polyanna Miranda; de Lima, Lilian Margareth Biagioni; da Silva, Marcelo Fernandes; de Lima Pereira, Sanívia Aparecida; Rodrigues, Virmondes; Rodrigues, Denise Bertulucci Rocha

2015-01-01

Although the pathophysiology of paracoccidioidomycosis (PCM) is not completely understood, the study of immune response against fungus has provided insight into understanding the natural course of the disease and its clinical manifestations, hence contributing to the development of preventive measures and treatment proposals. The aim of this study was to evaluate the histopathological and immunological aspects involved in the role of different effector and regulatory responses, as well as the correlation between the TLRs, Galectins, Matrix Metalloproteinases and cytoplasmic proteases of mast cells in this infection. Sixteen biopsy specimens with oral lesions of chronic PCM, as well as 13 sections of normal oral mucosa were analyzed. Histopathological and immunological aspects involved in the role of different effector and regulatory responses were evaluated. Indirect immunohistochemistry was performed for IL-17, IL-10, IL-4, TGF-β, FoxP3, Gal-1, Gal-3, Gal-9, TLR-2, TLR-4, MMP-3 and MMP-9, as well as for chymase and tryptase for mast cells identification. Fibrosis was quantified using Picrosirius. There was a significant increase in the area of fibrosis and in the number of cells expressing IL-10, IL-4, IL-17, FoxP3, Gal-3, TLR-2, MMP3 and MMP9 in patients with PCM in comparison with patients in the group control. There was no difference in the expression of TGF-β, TLR-4, Gal-1 or Gal-9. Mast cells number was found to be significantly lower in oral chronic PCM when compared to control samples after quantification of mast cells and expression of chymase and tryptase. PCM granulomas were classified to the morphological aspects in organized ou non-organized. Expression of IL-4 in non-organized granulomas was significantly higher. The proteins studied herein appear to play an important role in the development and maintenance of oral lesions of PCM, as well as in the processes of development and progression of lesions caused by the fungus and by the immune response associated with the infection. Copyright © 2014 Elsevier GmbH. All rights reserved.

[Comparison of fluoride concentrations in human, dog, fox and raccoon dog bones from northwestern Poland].

PubMed

Palczewska-Komsa, Mirona

2015-01-01

Since the beginning of the XXth there has been a constant increase in fluoride (F-) emissions into the environment, mainly due to the development of industry, the fluoridation of drinking water, and the widespread use of toothpaste containing fluoride. All these factors have resulted in an intensive accumulation of F- in the bodies of vertebrates, mainly in their bones. It is therefore reasonable to estimate the F- concentration in humans and other long-lived mammals. Accordingly, ecotoxicologists worldwide have looked for mammalian species that may serve as good bioindicators of environmental fluoride pollution. In contrast to ungulates, long-lived domestic mammals and wild carnivores have rarely been used for this purpose (including the dog, fox and raccoon dog). The main aims of this study were to: 1) investigate F- concentrations in bones obtained from humans, dog, fox and raccoon dog from northwestern Poland, 2) perform intra- and inter-specific comparisons of F- concentrations in the studied mammalian bones against the background of environmental and living conditions, 3) examine the relationship between concentrations of F- in bones and the age or age category of the studied mammals. The study material comprised bones of the hip joint obtained from 36 patients who underwent hip replacement in Szczecin, 43 dogs from Szczecin veterinary clinics, 32 foxes and 18 raccoon dogs provided by hunters, with the whole test material consisting of 129 samples. The indications of F- (using potentiometry with Thermo Orion ion-selective electrodes) were performed in triplicate. The F- concentration was expressed on a dry weight basis. Interspecific analysis showed that the largest number of differences in the concentrations of F- were between the fox and raccoon, and then between the dog and fox, and then between the dog and the wild canids (foxes and raccoon dogs together). Close statistically significant differences were also found between the samples from humans and the fox, and also between human and dog bones. There were no statistically significant differences in the concentrations of F- between humans and raccoons, humans and canids (dog, fox, raccoon dog together), and between dogs and raccoon dogs. Domesticated and wild canids are good bioindicators of environmental levels of fluoride, because they reflect the concentration of fluoride in bones observed in humans who lived in a similar area.

Quantification of transcription factor-DNA binding affinity in a living cell

PubMed Central

Belikov, Sergey; Berg, Otto G.; Wrange, Örjan

2016-01-01

The apparent dissociation constant (Kd) for specific binding of glucocorticoid receptor (GR) and androgen receptor (AR) to DNA was determined in vivo in Xenopus oocytes. The total nuclear receptor concentration was quantified as specifically retained [3H]-hormone in manually isolated oocyte nuclei. DNA was introduced by nuclear microinjection of single stranded phagemid DNA, chromatin is then formed during second strand synthesis. The fraction of DNA sites occupied by the expressed receptor was determined by dimethylsulphate in vivo footprinting and used for calculation of the receptor-DNA binding affinity. The forkhead transcription factor FoxA1 enhanced the DNA binding by GR with an apparent Kd of ∼1 μM and dramatically stimulated DNA binding by AR with an apparent Kd of ∼0.13 μM at a composite androgen responsive DNA element containing one FoxA1 binding site and one palindromic hormone receptor binding site known to bind one receptor homodimer. FoxA1 exerted a weak constitutive- and strongly cooperative DNA binding together with AR but had a less prominent effect with GR, the difference reflecting the licensing function of FoxA1 at this androgen responsive DNA element. PMID:26657626

Autophagy Driven by a Master Regulator of Hematopoiesis

PubMed Central

Kang, Yoon-A; Sanalkumar, Rajendran; O'Geen, Henriette; Linnemann, Amelia K.; Chang, Chan-Jung; Bouhassira, Eric E.; Farnham, Peggy J.; Keles, Sunduz

2012-01-01

Developmental and homeostatic remodeling of cellular organelles is mediated by a complex process termed autophagy. The cohort of proteins that constitute the autophagy machinery functions in a multistep biochemical pathway. Though components of the autophagy machinery are broadly expressed, autophagy can occur in specialized cellular contexts, and mechanisms underlying cell-type-specific autophagy are poorly understood. We demonstrate that the master regulator of hematopoiesis, GATA-1, directly activates transcription of genes encoding the essential autophagy component microtubule-associated protein 1 light chain 3B (LC3B) and its homologs (MAP1LC3A, GABARAP, GABARAPL1, and GATE-16). In addition, GATA-1 directly activates genes involved in the biogenesis/function of lysosomes, which mediate autophagic protein turnover. We demonstrate that GATA-1 utilizes the forkhead protein FoxO3 to activate select autophagy genes. GATA-1-dependent LC3B induction is tightly coupled to accumulation of the active form of LC3B and autophagosomes, which mediate mitochondrial clearance as a critical step in erythropoiesis. These results illustrate a novel mechanism by which a master regulator of development establishes a genetic network to instigate cell-type-specific autophagy. PMID:22025678

Regulatory T cells generated during cytomegalovirus in vitro stimulation of mononuclear cells from HIV-infected individuals on HAART correlate with decreased lymphocyte proliferation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jesser, Renee D.; Li, Shaobing; Weinberg, Adriana

2006-09-01

HIV-infected patients fail to fully recover cell-mediated immunity despite HAART. To identify regulatory factors, we studied the phenotype and function of in vitro cytomegalovirus (CMV)-stimulated T cells from HAART recipients. CFSE-measured proliferation showed CD4{sup +} and CD8{sup +} cells dividing in CMV-stimulated cultures. Compared with healthy controls, CMV-stimulated lymphocytes from HAART recipients had lower {sup 3}H-thymidine incorporation; lower IFN{gamma} and TNF{alpha} production; higher CD4{sup +}CD27{sup -}CD28{sup -} and CD8{sup +}CD27{sup -}CD28{sup -} frequencies; lower CD4{sup +}CD25{sup hi}; and higher FoxP3 expression in CD8{sup +}CD25{sup hi} cells. CMV-specific proliferation correlated with higher IFN{gamma}, TNF{alpha} and IL10 levels and higher CD4{sup +}perforin{supmore » +} and CD8{sup +}perforin{sup +} frequencies. Decreased proliferation correlated with higher CD4{sup +}CD27{sup -}CD28{sup -} frequencies and TGF{beta}1 production, which also correlated with each other. Anti-TGF{beta}1 neutralizing antibodies restored CMV-specific proliferation in a dose-dependent fashion. In HIV-infected subjects, decreased proliferation correlated with higher CMV-stimulated CD8{sup +}CD25{sup hi} frequencies and their FoxP3 expression. These data indicate that FoxP3- and TGF{beta}1-expressing regulatory T cells contribute to decreased immunity in HAART recipients.« less

Program Specificity for Ptf1a in Pancreas versus Neural Tube Development Correlates with Distinct Collaborating Cofactors and Chromatin Accessibility

PubMed Central

Meredith, David M.; Borromeo, Mark D.; Deering, Tye G.; Casey, Bradford H.; Savage, Trisha K.; Mayer, Paul R.; Hoang, Chinh; Tung, Kuang-Chi; Kumar, Manonmani; Shen, Chengcheng; Swift, Galvin H.

2013-01-01

The lineage-specific basic helix-loop-helix transcription factor Ptf1a is a critical driver for development of both the pancreas and nervous system. How one transcription factor controls diverse programs of gene expression is a fundamental question in developmental biology. To uncover molecular strategies for the program-specific functions of Ptf1a, we identified bound genomic regions in vivo during development of both tissues. Most regions bound by Ptf1a are specific to each tissue, lie near genes needed for proper formation of each tissue, and coincide with regions of open chromatin. The specificity of Ptf1a binding is encoded in the DNA surrounding the Ptf1a-bound sites, because these regions are sufficient to direct tissue-restricted reporter expression in transgenic mice. Fox and Sox factors were identified as potential lineage-specific modifiers of Ptf1a binding, since binding motifs for these factors are enriched in Ptf1a-bound regions in pancreas and neural tube, respectively. Of the Fox factors expressed during pancreatic development, Foxa2 plays a major role. Indeed, Ptf1a and Foxa2 colocalize in embryonic pancreatic chromatin and can act synergistically in cell transfection assays. Together, these findings indicate that lineage-specific chromatin landscapes likely constrain the DNA binding of Ptf1a, and they identify Fox and Sox gene families as part of this process. PMID:23754747

Generation of Wheat Transcription Factor FOX Rice Lines and Systematic Screening for Salt and Osmotic Stress Tolerance.

PubMed

Wu, Jinxia; Zhang, Zhiguo; Zhang, Qian; Liu, Yayun; Zhu, Butuo; Cao, Jian; Li, Zhanpeng; Han, Longzhi; Jia, Jizeng; Zhao, Guangyao; Sun, Xuehui

2015-01-01

Transcription factors (TFs) play important roles in plant growth, development, and responses to environmental stress. In this study, we collected 1,455 full-length (FL) cDNAs of TFs, representing 45 families, from wheat and its relatives Triticum urartu, Aegilops speltoides, Aegilops tauschii, Triticum carthlicum, and Triticum aestivum. More than 15,000 T0 TF FOX (Full-length cDNA Over-eXpressing) rice lines were generated; of these, 10,496 lines set seeds. About 14.88% of the T0 plants showed obvious phenotypic changes. T1 lines (5,232 lines) were screened for salt and osmotic stress tolerance using 150 mM NaCl and 20% (v/v) PEG-4000, respectively. Among them, five lines (591, 746, 1647, 1812, and J4065) showed enhanced salt stress tolerance, five lines (591, 746, 898, 1078, and 1647) showed enhanced osmotic stress tolerance, and three lines (591, 746, and 1647) showed both salt and osmotic stress tolerance. Further analysis of the T-DNA flanking sequences showed that line 746 over-expressed TaEREB1, line 898 over-expressed TabZIPD, and lines 1812 and J4065 over-expressed TaOBF1a and TaOBF1b, respectively. The enhanced salt and osmotic stress tolerance of lines 898 and 1812 was confirmed by retransformation of the respective genes. Our results demonstrate that a heterologous FOX system may be used as an alternative genetic resource for the systematic functional analysis of the wheat genome.

Pituitary content of luteinizing hormone reveals species differences in the reproductive synchrony between males and females in Australian flying-foxes (genus Pteropus).

PubMed

O'Brien, G M; McFarlane, J R; Kearney, P J

2003-01-01

Flying-foxes (genus suborder, Pteropus Megachiroptera) are long-lived tropical mammals. Their seasonal reproduction appears to be regulated by an endogenous, circannual rhythm modified by multiple environmental cues. Luteinizing hormone (LH) content in pituitary extracts was examined to establish the broad time-frame of pituitary stages in the reproductive seasonality of the flying-foxes. A comparison was made between the grey-headed flying-fox P. poliocephalus, which mates and conceives in autumn, and the little red flying-fox P. scapulatus, which mates and conceives in spring. In P. scapulatus, LH was maximum during the spring mating season at 1494 ng mg(-1) in males and 896 ng mg(-1) in females. In P. poliocephalus males, LH increased to 1082 ng mg(-1) in early summer, 4 months before the mating season; LH concentrations in male P. poliocephalus returned to a low of 222 ng mg(-1) by the time of the autumn mating, by which time the female P. poliocephalus expressed elevated LH concentrations (624 ng mg(-1)). Apparently in P. poliocephalus, the peak LH concentrations in females are delayed by 4 months relative to LH concentrations in males. This is associated with 4 months of energetic courtship on the part of male P. poliocephalus, which is not observed in P. scapulatus, the fertility of which is synchronized between the sexes. The heterologous radioimmunoassay developed using monoclonal antibody 518B7 confirmed classic suppression of LH during pregnancy and lactation in flying-foxes and LH elevation in response to gonadectomy. Juveniles generally had pituitary levels similar to non-breeding levels in adults.

Gene expression profiles in Parkinson disease prefrontal cortex implicate FOXO1 and genes under its transcriptional regulation.

PubMed

Dumitriu, Alexandra; Latourelle, Jeanne C; Hadzi, Tiffany C; Pankratz, Nathan; Garza, Dan; Miller, John P; Vance, Jeffery M; Foroud, Tatiana; Beach, Thomas G; Myers, Richard H

2012-06-01

Parkinson disease (PD) is a complex neurodegenerative disorder with largely unknown genetic mechanisms. While the degeneration of dopaminergic neurons in PD mainly takes place in the substantia nigra pars compacta (SN) region, other brain areas, including the prefrontal cortex, develop Lewy bodies, the neuropathological hallmark of PD. We generated and analyzed expression data from the prefrontal cortex Brodmann Area 9 (BA9) of 27 PD and 26 control samples using the 44K One-Color Agilent 60-mer Whole Human Genome Microarray. All samples were male, without significant Alzheimer disease pathology and with extensive pathological annotation available. 507 of the 39,122 analyzed expression probes were different between PD and control samples at false discovery rate (FDR) of 5%. One of the genes with significantly increased expression in PD was the forkhead box O1 (FOXO1) transcription factor. Notably, genes carrying the FoxO1 binding site were significantly enriched in the FDR-significant group of genes (177 genes covered by 189 probes), suggesting a role for FoxO1 upstream of the observed expression changes. Single-nucleotide polymorphisms (SNPs) selected from a recent meta-analysis of PD genome-wide association studies (GWAS) were successfully genotyped in 50 out of the 53 microarray brains, allowing a targeted expression-SNP (eSNP) analysis for 52 SNPs associated with PD affection at genome-wide significance and the 189 probes from FoxO1 regulated genes. A significant association was observed between a SNP in the cyclin G associated kinase (GAK) gene and a probe in the spermine oxidase (SMOX) gene. Further examination of the FOXO1 region in a meta-analysis of six available GWAS showed two SNPs significantly associated with age at onset of PD. These results implicate FOXO1 as a PD-relevant gene and warrant further functional analyses of its transcriptional regulatory mechanisms.

Survivin as a Novel Biomarker in the Pathogenesis of Acne Vulgaris and Its Correlation to Insulin-Like Growth Factor-I

PubMed Central

Assaf, Hanan A.; Abdel-Maged, Wafaa M.; Elsadek, Bakheet E. M.; Adly, Mohamed A.; Ali, Soher A.

2016-01-01

Survivin, a member of the inhibitor of apoptosis protein family, has an important role in cell cycle regulation. Insulin-like growth factor-I (IGF-I) is a polypeptide hormone with wide range of biologic effects including stimulation of lipogenesis in sebaceous glands. Their overexpression in some fibrotic disorders suggests a possible implication of both IGF-I and survivin in the pathogenesis of acne and/or acne scars. The current study aimed to assess and correlate serum levels of IGF-I and survivin in patients with active acne vulgaris and postinflammatory acne scars and to evaluate their lesional expressions in comparison to healthy controls. Serum IGF-I and survivin were estimated using commercially available ELISA kits and their tissues expressions were investigated using Western blotting. Our findings suggest that IGF-I and survivin could play potential roles in the pathogenesis of active acne vulgaris and more importantly in postinflammatory acne scars with significant positive correlation coefficient between serum levels of IGF-I and survivin which support IGF-I-/PI3K-/AKT-mediated downregulation of nuclear expression of FoxO transcription factors resulting in enhanced survivin expression. PMID:27803511

Survivin as a Novel Biomarker in the Pathogenesis of Acne Vulgaris and Its Correlation to Insulin-Like Growth Factor-I.

PubMed

Assaf, Hanan A; Abdel-Maged, Wafaa M; Elsadek, Bakheet E M; Hassan, Mohammed H; Adly, Mohamed A; Ali, Soher A

2016-01-01

Survivin, a member of the inhibitor of apoptosis protein family, has an important role in cell cycle regulation. Insulin-like growth factor-I (IGF-I) is a polypeptide hormone with wide range of biologic effects including stimulation of lipogenesis in sebaceous glands. Their overexpression in some fibrotic disorders suggests a possible implication of both IGF-I and survivin in the pathogenesis of acne and/or acne scars. The current study aimed to assess and correlate serum levels of IGF-I and survivin in patients with active acne vulgaris and postinflammatory acne scars and to evaluate their lesional expressions in comparison to healthy controls. Serum IGF-I and survivin were estimated using commercially available ELISA kits and their tissues expressions were investigated using Western blotting. Our findings suggest that IGF-I and survivin could play potential roles in the pathogenesis of active acne vulgaris and more importantly in postinflammatory acne scars with significant positive correlation coefficient between serum levels of IGF-I and survivin which support IGF-I-/PI3K-/AKT-mediated downregulation of nuclear expression of FoxO transcription factors resulting in enhanced survivin expression.

Construction of an integrated gene regulatory network link to stress-related immune system in cattle.

PubMed

Behdani, Elham; Bakhtiarizadeh, Mohammad Reza

2017-10-01

The immune system is an important biological system that is negatively impacted by stress. This study constructed an integrated regulatory network to enhance our understanding of the regulatory gene network used in the stress-related immune system. Module inference was used to construct modules of co-expressed genes with bovine leukocyte RNA-Seq data. Transcription factors (TFs) were then assigned to these modules using Lemon-Tree algorithms. In addition, the TFs assigned to each module were confirmed using the promoter analysis and protein-protein interactions data. Therefore, our integrated method identified three TFs which include one TF that is previously known to be involved in immune response (MYBL2) and two TFs (E2F8 and FOXS1) that had not been recognized previously and were identified for the first time in this study as novel regulatory candidates in immune response. This study provides valuable insights on the regulatory programs of genes involved in the stress-related immune system.

Effect of High Temperature- and High Pressure-Treated Red Ginseng on Lipolysis and Lipid Oxidation in C2C12 Myotubes.

PubMed

Yu, Seok-Yeong; Lee, Jin-Ha; Cho, MyoungLae; Lee, Jong Seok; Hong, Hee-Do; Lee, Young-Chul; Kim, Young-Chan; Cho, Chang-Won; Kim, Kyung-Tack; Lee, Ok-Hwan

2016-01-01

Korean red ginseng (KRG), a highly valuable medicinal herb in oriental societies, has biological activity similar to that of Panax ginseng. Recently, it has been discovered that the biological activities of red ginseng can vary according to heating and steaming processes under different conditions that change the principal components of KRG and result in changes in biological activity. This study evaluated and compared the effects of high temperature- and high pressure-treated red ginseng (HRG) and commercial red ginseng (RG) on β-oxidation in C2C12 myotubes. HRG enhanced the phosphorylation levels of AMP-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC), but RG did not affect the phosphorylation of AMPK in C2C12 myotubes. HRG also promoted the nuclear translocation of forkhead box protein O1 (FoxO1), and the translocation exerted an increase in the protein expression of adipose triglyceride lipase (ATGL). As a consequence, HRG increased the mRNA expression level of carnitine palmitoyltransferase 1 (CPT-1) compared to the control. Taken together, our results indicated that HRG promotes the lipolysis of triglycerides and mitochondrial β-oxidation of fatty acids in C2C12 myotubes, suggesting that alterations to the principal components by high temperature and pressure may positively influence the nutraceutical functions of HRG.

Tracking Single Cells in Live Animals Using a Photoconvertible Near-Infrared Cell Membrane Label

PubMed Central

Wu, Juwell; Runnels, Judith M.; Turcotte, Raphaël; Celso, Cristina Lo; Scadden, David T.; Strom, Terry B.; Lin, Charles P.

2013-01-01

We describe a novel photoconversion technique to track individual cells in vivo using a commercial lipophilic membrane dye, DiR. We show that DiR exhibits a permanent fluorescence emission shift (photoconversion) after light exposure and does not reacquire the original color over time. Ratiometric imaging can be used to distinguish photoconverted from non-converted cells with high sensitivity. Combining the use of this photoconvertible dye with intravital microscopy, we tracked the division of individual hematopoietic stem/progenitor cells within the calvarium bone marrow of live mice. We also studied the peripheral differentiation of individual T cells by tracking the gain or loss of FoxP3-GFP expression, a marker of the immune suppressive function of CD4+ T cells. With the near-infrared photoconvertible membrane dye, the entire visible spectral range is available for simultaneous use with other fluorescent proteins to monitor gene expression or to trace cell lineage commitment in vivo with high spatial and temporal resolution. PMID:23990881

Tracking single cells in live animals using a photoconvertible near-infrared cell membrane label.

PubMed

Carlson, Alicia L; Fujisaki, Joji; Wu, Juwell; Runnels, Judith M; Turcotte, Raphaël; Spencer, Joel A; Celso, Cristina Lo; Scadden, David T; Strom, Terry B; Lin, Charles P

2013-01-01

We describe a novel photoconversion technique to track individual cells in vivo using a commercial lipophilic membrane dye, DiR. We show that DiR exhibits a permanent fluorescence emission shift (photoconversion) after light exposure and does not reacquire the original color over time. Ratiometric imaging can be used to distinguish photoconverted from non-converted cells with high sensitivity. Combining the use of this photoconvertible dye with intravital microscopy, we tracked the division of individual hematopoietic stem/progenitor cells within the calvarium bone marrow of live mice. We also studied the peripheral differentiation of individual T cells by tracking the gain or loss of FoxP3-GFP expression, a marker of the immune suppressive function of CD4(+) T cells. With the near-infrared photoconvertible membrane dye, the entire visible spectral range is available for simultaneous use with other fluorescent proteins to monitor gene expression or to trace cell lineage commitment in vivo with high spatial and temporal resolution.

USP39 promotes the growth of human hepatocellular carcinoma in vitro and in vivo.

PubMed

Yuan, Xianwen; Sun, Xitai; Shi, Xiaolei; Jiang, Chunping; Yu, Decai; Zhang, Weiwei; Guan, Wenxian; Zhou, Jianxin; Wu, Yafu; Qiu, Yudong; Ding, Yitao

2015-08-01

Ubiquitin specific protease 39 (USP39) plays an important role in mRNA splicing. In the present study, we investigated the role of USP39 in regulating the growth of hepatocellular carcinoma (HCC). We detected USP39 expression in more than 100 HCC clinical samples. The USP39 expression was significantly higher in the tumor tissues compared to the adjacent normal tissues, and was strongly associated with the pathological grade of HCC. USP39 knockdown inhibited cell proliferation and colony formation in vitro in the HepG2 cells, while upregulation of USP39 promoted tumor cell growth. FCM assay showed that USP39 knockdown led to G2/M arrest and induced apoptosis in the HepG2 cells. USP39 knockdown by shRNA inhibited xenograft tumor growth in nude mice. Moreover, USP39 knockdown led to the upregulation of p-Cdc2 and downregulation of p-Cdc25c and p-myt1, while the expression of total Cdc2, Cdc25c and myt1 was not changed in the USP39-knockdown cells. We also found that p-Cdc2 was decreased in the USP39-overexpressing cells and was upregulated in the xenografted tumors derived from the HepG2/KD cells from nude mice. Meanwhile, the expression levels of FoxM1 and its target genes PLK1 and cyclin B1 were decreased in the USP39-knockdown cells. These results suggest that USP39 may contribute to FoxM1 splicing in HCC tumor cells. Our data indicate that USP39 knockdown inhibited the growth of HCC both in vitro and in vivo through G2/M arrest, which was partly achieved via the inhibition of FoxM1 splicing.

Analysis of the Structure and Function of FOX-4 Cephamycinase

PubMed Central

Lefurgy, S. T.; Malashkevich, V. N.; Aguilan, J. T.; Nieves, E.; Mundorff, E. C.; Biju, B.; Noel, M. A.; Toro, R.; Baiwir, D.; Papp-Wallace, K. M.; Almo, S. C.; Frere, J.-M.; Bou, G.

2015-01-01

Class C β-lactamases poorly hydrolyze cephamycins (e.g., cefoxitin, cefotetan, and moxalactam). In the past 2 decades, a new family of plasmid-based AmpC β-lactamases conferring resistance to cefoxitin, the FOX family, has grown to include nine unique members descended from the Aeromonas caviae chromosomal AmpC. To understand the basis for the unique cephamycinase activity in the FOX family, we determined the first X-ray crystal structures of FOX-4, apo enzyme and the acyl-enzyme with its namesake compound, cefoxitin, using the Y150F deacylation-deficient variant. Notably, recombinant expression of N-terminally tagged FOX-4 also yielded an inactive adenylylated enzyme form not previously observed in β-lactamases. The posttranslational modification (PTM), which occurs on the active site Ser64, would not seem to provide a selective advantage, yet might present an opportunity for the design of novel antibacterial drugs. Substantial ligand-induced changes in the enzyme are seen in the acyl-enzyme complex, particularly the R2 loop and helix H10 (P289 to N297), with movement of F293 by 10.3 Å. Taken together, this study provides the first picture of this highly proficient class C cephamycinase, uncovers a novel PTM, and suggests a possible cephamycin resistance mechanism involving repositioning of the substrate due to the presence of S153P, N289P, and N346I substitutions in the ligand binding pocket. PMID:26525784

Analysis of the Structure and Function of FOX-4 Cephamycinase.

PubMed

Lefurgy, S T; Malashkevich, V N; Aguilan, J T; Nieves, E; Mundorff, E C; Biju, B; Noel, M A; Toro, R; Baiwir, D; Papp-Wallace, K M; Almo, S C; Frere, J-M; Bou, G; Bonomo, R A

2016-02-01

Class C β-lactamases poorly hydrolyze cephamycins (e.g., cefoxitin, cefotetan, and moxalactam). In the past 2 decades, a new family of plasmid-based AmpC β-lactamases conferring resistance to cefoxitin, the FOX family, has grown to include nine unique members descended from the Aeromonas caviae chromosomal AmpC. To understand the basis for the unique cephamycinase activity in the FOX family, we determined the first X-ray crystal structures of FOX-4, apo enzyme and the acyl-enzyme with its namesake compound, cefoxitin, using the Y150F deacylation-deficient variant. Notably, recombinant expression of N-terminally tagged FOX-4 also yielded an inactive adenylylated enzyme form not previously observed in β-lactamases. The posttranslational modification (PTM), which occurs on the active site Ser64, would not seem to provide a selective advantage, yet might present an opportunity for the design of novel antibacterial drugs. Substantial ligand-induced changes in the enzyme are seen in the acyl-enzyme complex, particularly the R2 loop and helix H10 (P289 to N297), with movement of F293 by 10.3 Å. Taken together, this study provides the first picture of this highly proficient class C cephamycinase, uncovers a novel PTM, and suggests a possible cephamycin resistance mechanism involving repositioning of the substrate due to the presence of S153P, N289P, and N346I substitutions in the ligand binding pocket. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Increased numbers of FoxP3-expressing CD4+ CD25+ regulatory T cells in peripheral blood from dogs with atopic dermatitis and its correlation with disease severity.

PubMed

Hauck, Verena; Hügli, Patrick; Meli, Marina L; Rostaher, Ana; Fischer, Nina; Hofmann-Lehmann, Regina; Favrot, Claude

2016-02-01

Atopic dermatitis (AD) is a common chronic inflammatory skin disease of humans and dogs. Regulatory T cells (Tregs) are essential controllers of immune homeostasis and have been shown to play a key role in human AD, even though frequencies of Tregs in atopic human patients vary greatly. Only two studies have reported Treg numbers in the peripheral blood of dogs with canine AD (CAD). This study aimed to assess the numbers of circulating Tregs in healthy and atopic dogs, and to determine whether Treg numbers correlate with age, sex, disease severity or pre-treatment. Client-owned dogs including 14 healthy dogs and 35 dogs with CAD. Expression of Tregs in peripheral blood mononuclear cells was evaluated by flow cytometry. Tregs were phenotypically identified as T cells triple positive for CD4, CD25 and FoxP3. The percentage of circulating CD4(+)  CD25(+)  FoxP3(+) Tregs in atopic dogs was increased significantly compared to healthy dogs (mean 2.1% versus 1%, P = 0.002) and correlated with disease severity (Pruritus Scale: r = 0.48, P = 0.003; CADESI-04: r = 0.34, P = 0.044). No significant differences in age or sex were found in either group and pre-treatment had no influence on results for atopic dogs. Data suggest that, as in humans, CD4(+)  CD25(+)  FoxP3(+) Tregs may contribute to the pathogenesis of CAD as indicated by an association between Treg frequency and disease severity. Further investigation is required to improve the understanding of the role of Tregs in atopic dogs. © 2015 ESVD and ACVD.

Expansion of CD25-Negative Forkhead Box P3-Positive T Cells during HIV and Mycobacterium tuberculosis Infection.

PubMed

Angerami, Matías T; Suarez, Guadalupe V; Vecchione, María B; Laufer, Natalia; Ameri, Diego; Ben, Graciela; Perez, Hector; Sued, Omar; Salomón, Horacio; Quiroga, María F

2017-01-01

Tuberculosis (TB) and HIV alter the immune system, and coinfected (HIV-TB) individuals usually present deregulations of T-lymphocytic immune response. We previously observed an increased frequency of "unconventional" CD4 + CD25 - FoxP3 + Treg (uTreg) population during HIV-TB disease. Therefore, we aimed to explore the phenotype and function of uTreg and conventional CD4 + CD25 + FoxP3 + Treg subsets (cTreg) in this context. We evaluated the expression of CD39, programmed cell death protein 1 (PD1), glucocorticoid-induced tumor necrosis factor receptor (GITR), and the effector/memory distribution by flow cytometry in cTreg and uTreg. Also, IL-10, TGF-β, IFN-γ production, and the suppressor capacity of uTregs were analyzed in cocultures with effector lymphocytes and compared with the effect of regulatory T cells (Tregs). We found diminished expression of CD39 and higher levels of PD1 on uTreg compared to cTreg in both HIV-TB and healthy donors (HD). In addition, uTreg and cTreg showed differences in maturation status in both HIV-TB and HD groups, due to the expansion of effector memory uTregs. Interestingly, both HIV-TB and HD showed a pronounced production of IFN-γ in uTreg population, though no significant differences were observed for IL-10 and TGF-β production between uTreg and cTreg. Moreover, IFN-γ + cells were restricted to the CD39 - uTreg population. Finally, when the suppressor capacity was evaluated, both uTreg and cTreg inhibited polyclonal T cell-proliferation and IFN-γ production in a similar extent. These findings suggest that uTregs, which are expanded during HIV-TB coinfection, exert regulatory functions in a similar way to cTregs despite an altered surface expression of Treg characteristic markers and differences in cytokine production.

Expansion of CD25-Negative Forkhead Box P3-Positive T Cells during HIV and Mycobacterium tuberculosis Infection

PubMed Central

Angerami, Matías T.; Suarez, Guadalupe V.; Vecchione, María B.; Laufer, Natalia; Ameri, Diego; Ben, Graciela; Perez, Hector; Sued, Omar; Salomón, Horacio; Quiroga, María F.

2017-01-01

Tuberculosis (TB) and HIV alter the immune system, and coinfected (HIV-TB) individuals usually present deregulations of T-lymphocytic immune response. We previously observed an increased frequency of “unconventional” CD4+CD25−FoxP3+ Treg (uTreg) population during HIV-TB disease. Therefore, we aimed to explore the phenotype and function of uTreg and conventional CD4+CD25+FoxP3+ Treg subsets (cTreg) in this context. We evaluated the expression of CD39, programmed cell death protein 1 (PD1), glucocorticoid-induced tumor necrosis factor receptor (GITR), and the effector/memory distribution by flow cytometry in cTreg and uTreg. Also, IL-10, TGF-β, IFN-γ production, and the suppressor capacity of uTregs were analyzed in cocultures with effector lymphocytes and compared with the effect of regulatory T cells (Tregs). We found diminished expression of CD39 and higher levels of PD1 on uTreg compared to cTreg in both HIV-TB and healthy donors (HD). In addition, uTreg and cTreg showed differences in maturation status in both HIV-TB and HD groups, due to the expansion of effector memory uTregs. Interestingly, both HIV-TB and HD showed a pronounced production of IFN-γ in uTreg population, though no significant differences were observed for IL-10 and TGF-β production between uTreg and cTreg. Moreover, IFN-γ+ cells were restricted to the CD39− uTreg population. Finally, when the suppressor capacity was evaluated, both uTreg and cTreg inhibited polyclonal T cell-proliferation and IFN-γ production in a similar extent. These findings suggest that uTregs, which are expanded during HIV-TB coinfection, exert regulatory functions in a similar way to cTregs despite an altered surface expression of Treg characteristic markers and differences in cytokine production. PMID:28536578

Mesenchymal stem cells induce functionally active T-regulatory lymphocytes in a paracrine fashion and ameliorate experimental autoimmune uveitis.

PubMed

Tasso, Roberta; Ilengo, Cristina; Quarto, Rodolfo; Cancedda, Ranieri; Caspi, Rachel R; Pennesi, Giuseppina

2012-02-01

Mesenchymal stem/progenitor cells (MSCs) have regenerative and immunomodulatory properties, exerted by cell-cell contact and in a paracrine fashion. Part of their immunosuppressive activity has been ascribed to their ability to promote the induction of CD4+CD25+FoxP3+ T lymphocytes with regulatory functions (Treg). Here the authors studied the effect of MSCs on the induction of Treg and on the development of autoimmunity, and they examined the possibility that MSC-mediated Treg induction could be attributed to the secretion of soluble factors. The authors induced experimental autoimmune uveitis (EAU) in mice by immunization with the 1-20 peptide of the intraphotoreceptor binding protein. At the same time, some of the animals were treated intraperitoneally with syngeneic MSCs. The authors checked T-cell responses and in vitro Treg conversion by cell proliferation and blocking assays, in cell-cell contact and transwell settings. TGFβ and TGFβ receptor gene expression analyses were performed by real-time PCR. The authors found that a single intraperitoneal injection of MSCs was able to significantly attenuate EAU and that a significantly higher percentage of adaptive Treg was present in MSC-treated mice than in MSC-untreated animals. In vitro blocking of antigen presentation by major histocompatibility complex class II precluded priming and clonal expansion of antigen-specific Treg, whereas blockade of TGFβ impaired the expression of FoxP3, preventing the conversion of CD4+ T cells into functionally active Treg. The authors demonstrated that MSCs can inhibit EAU and that their immunomodulatory function is due at least in part to the induction of antigen-specific Treg in a paracrine fashion by secreting TGFβ.

Efficacy of T Regulatory Cells, Th17 Cells and the Associated Markers in Monitoring Tuberculosis Treatment Response

PubMed Central

Agrawal, Sonali; Parkash, Om; Palaniappan, Alangudi Natarajan; Bhatia, Ashok Kumar; Kumar, Santosh; Chauhan, Devendra Singh; Madhan Kumar, M.

2018-01-01

Treatment monitoring is an essential aspect for tuberculosis (TB) disease management. Sputum smear microscopy is the only available tool for monitoring, but it suffers from demerits. Therefore, we sought to evaluate markers and cellular subsets of T regulatory (Treg) cells and T helper (Th) 17 cells in pulmonary TB patients (PTB) for TB treatment monitoring. Peripheral blood mononuclear cells (PBMCs) were stimulated in vitro (with purified protein derivative (PPD)) overnight which was followed by a polychromatic flow cytometry approach to study Treg and Th17 markers and cellular subsets in PTB (n = 12) undergoing antituberculous treatment (ATT). The baseline levels of these markers and cellular subsets were evaluated in normal healthy subjects (NHS). We observed a significant decrease in the expression of CD25 (p<0.01) marker and percentage of T-cell subsets like CD4+CD25+ (p<0.001) and CD4+CD25+CD39+ (p<0.05) at the end of intensive phase (IP) as well as in the continuation phase (CP) of ATT. A decrease in CD25 marker expression and percentage of CD4+CD25+ T cell subset showed a positive correlation to sputum conversion both in high and low sputum positive PTB. In eight PTB with cavitary lesions, only CD4+CD25+FoxP3 Treg subset manifested a significant decrease at the end of CP. Thus, results of this study show that CD25 marker and CD4+CD25+ T cells can serve as better markers for monitoring TB treatment efficacy. The Treg subset CD4+CD25+FoxP3 may be useful for prediction of favorable response in PTB with extensive lung lesions. However, these findings have to be evaluated in a larger patient cohort. PMID:29472922

Momordica charantia (bitter melon) attenuates high-fat diet-associated oxidative stress and neuroinflammation.

PubMed

Nerurkar, Pratibha V; Johns, Lisa M; Buesa, Lance M; Kipyakwai, Gideon; Volper, Esther; Sato, Ryuei; Shah, Pranjal; Feher, Domonkos; Williams, Philip G; Nerurkar, Vivek R

2011-06-03

The rising epidemic of obesity is associated with cognitive decline and is considered as one of the major risk factors for neurodegenerative diseases. Neuroinflammation is a critical component in the progression of several neurological and neurodegenerative diseases. Increased metabolic flux to the brain during overnutrition and obesity can orchestrate stress response, blood-brain barrier (BBB) disruption, recruitment of inflammatory immune cells from peripheral blood and microglial cells activation leading to neuroinflammation. The lack of an effective treatment for obesity-associated brain dysfunction may have far-reaching public health ramifications, urgently necessitating the identification of appropriate preventive and therapeutic strategies. The objective of our study was to investigate the neuroprotective effects of Momordica charantia (bitter melon) on high-fat diet (HFD)-associated BBB disruption, stress and neuroinflammatory cytokines. C57BL/6 female mice were fed HFD with and without bitter melon (BM) for 16 weeks. BBB disruption was analyzed using Evans blue dye. Phosphate-buffered saline (PBS) perfused brains were analyzed for neuroinflammatory markers such as interleukin-22 (IL-22), IL-17R, IL-16, NF-κB1, and glial cells activation markers such as Iba1, CD11b, GFAP and S100β. Additionally, antioxidant enzymes, ER-stress proteins, and stress-resistant transcription factors, sirtuin 1 (Sirt1) and forkhead box class O transcription factor (FoxO) were analyzed using microarray, quantitative real-time RT-PCR, western immunoblotting and enzymatic assays. Systemic inflammation was analyzed using cytokine antibody array. BM ameliorated HFD-associated changes in BBB permeability as evident by reduced leakage of Evans blue dye. HFD-induced glial cells activation and expression of neuroinflammatory markers such as NF-κB1, IL-16, IL-22 as well as IL-17R were normalized in the brains of mice supplemented with BM. Similarly, HFD-induced brain oxidative stress was significantly reduced by BM supplementation with a concomitant reduction in FoxO, normalization of Sirt1 protein expression and up-regulation of Sirt3 mRNA expression. Furthermore, plasma antioxidant enzymes and pro-inflammatory cytokines were also normalized in mice fed HFD with BM as compared to HFD-fed mice. Functional foods such as BM offer a unique therapeutic strategy to improve obesity-associated peripheral inflammation and neuroinflammation.

FOXP3, CBLB and ITCH gene expression and cytotoxic T lymphocyte antigen 4 expression on CD4+CD25high T cells in multiple sclerosis

PubMed Central

Sellebjerg, F; Krakauer, M; Khademi, M; Olsson, T; Sørensen, P S

2012-01-01

Expression of the forkhead box protein 3 (FoxP3) transcription factor is regulated by the E3 ubiquitin ligases Itch and Cbl-b and induces regulatory activity CD4+CD25high T cells. Treatment with interferon (IFN)-β enhances regulatory T cell activity in multiple sclerosis (MS). We studied the phenotype of CD4+CD25high T cells in MS by flow cytometry and its relationship with expression of the FOXP3, ITCH and CBLB genes. We found that untreated MS patients had lower cell surface expression of cytotoxic T lymphocyte antigen 4 (CTLA-4) on CD4+CD25high T cells and higher intracellular CTLA-4 expression than healthy controls. Cell surface expression of CTLA-4 on CD4+CD25high T cells correlated with expression of FOXP3 mRNA in untreated patients and increased significantly with time from most recent injection in patients treated with IFN-β. FOXP3 mRNA expression correlated with CBLB and ITCH and T helper type 2 cytokine mRNA expression in MS patients. These data link expression of FOXP3, CBLB and ITCH mRNA and CTLA-4 expression on the surface of CD4+CD25high T cell in MS. We hypothesize that this may reflect alterations in the inhibitory effect of CTLA-4 or in regulatory T cell function. PMID:23039885

Molecular dynamic simulations for FOX-7 and FOX-7 based PBXs.

PubMed

Wang, Junying; Jin, Shaohua; Chen, Shusen; Li, Lijie; Wang, Dongxu; Lu, Zhiyan; Wang, Na; Wang, Junfeng

2018-06-01

Molecular dynamic (MD) simulations were applied to investigate the binding energies and mechanical properties of 1,1-diamino-2,2-dinitroethene (FOX-7) based polymer bonded explosives (PBXs) with ethylenevinylacetate copolymer (EVA), fluorine (F2641), hydroxyl-terminated polybutadiene (HTPB), and styrene butadiene styrene block copolymer (SBS). The binding energies between FOX-7 and the four polymer binders are different, of which the descending order is FOX-7/HTPB ≈ FOX-7/SBS > FOX-7/EVA > FOX-7/F2641. Furthermore, the (002) surface of FOX-7 has the strongest interaction with the four polymers. The mechanical properties (elastic moduli and Poisson's ratio) of pure FOX-7 and FOX-7 based PBXs were obtained. The results show that the descending order of the ability of polymer binders to improve plasticity of PBXs is SBS > F2641 > EVA > HTPB. The formability of FOX-7 based PBXs is better than that of pure FOX-7, as the order of FOX-7/SBS > FOX-7/EVA > FOX-7/F2641 > FOX-7/HTPB > FOX-7 shows. Poisson's ratio of SBS is the highest. The calculated detonation performances for pure FOX-7 and FOX-7 based PBXs show that the detonation properties of explosives slightly decreases when the mass ratio of binder is about 5%. All the theoretical detonation velocities of FOX-7 based PBXs are higher than 8500 m/s.

Role of Autism Susceptibility Gene, CNTNAP2, in Neural Circuitry for Vocal Communication

DTIC Science & Technology

2012-10-01

experiments designed to test this hypothesis, we have now shown that FoxP2 protein in RA follows the mRNA pattern, with a striking change between...associated protein-like 2 (Cntnap2) is an exc iting molecule for the study of the genetic basis of language. In humans, Cntnap2 is a target of the FOXP2

Characterization of human mitochondrial ferritin promoter: identification of transcription factors and evidences of epigenetic control

NASA Astrophysics Data System (ADS)

Guaraldo, Michela; Santambrogio, Paolo; Rovelli, Elisabetta; di Savino, Augusta; Saglio, Giuseppe; Cittaro, Davide; Roetto, Antonella; Levi, Sonia

2016-09-01

Mitochondrial ferritin (FtMt) is an iron storage protein belonging to the ferritin family but, unlike the cytosolic ferritin, it has an iron-unrelated restricted tissue expression. FtMt appears to be preferentially expressed in cell types characterized by high metabolic activity and oxygen consumption, suggesting a role in protecting mitochondria from iron-dependent oxidative damage. The human gene (FTMT) is intronless and its promoter region has not been described yet. To analyze the regulatory mechanisms controlling FTMT expression, we characterized the 5‧ flanking region upstream the transcriptional starting site of FTMT by in silico enquiry of sequences conservation, DNA deletion analysis, and ChIP assay. The data revealed a minimal promoter region and identified the presence of SP1, CREB and YY1 as positive regulators, and GATA2, FoxA1 and C/EBPβ as inhibitors of the transcriptional regulation. Furthermore, the FTMT transcription is increased by acetylating and de-methylating agent treatments in K562 and HeLa cells. These treatments up-regulate FtMt expression even in fibroblasts derived from a Friedreich ataxia patient, where it might exert a beneficial effect against mitochondrial oxidative damage. The expression of FTMT appears regulated by a complex mechanism involving epigenetic events and interplay between transcription factors.

Forkhead box O3 plays a role in skeletal muscle atrophy through expression of E3 ubiquitin ligases MuRF-1 and atrogin-1 in Cushing's syndrome.

PubMed

Kang, Seol-Hee; Lee, Hae-Ahm; Kim, Mina; Lee, Eunjo; Sohn, Uy Dong; Kim, Inkyeom

2017-06-01

Cushing's syndrome is caused by overproduction of the adrenocorticotropic hormone (ACTH), which stimulates the adrenal grand to make cortisol. Skeletal muscle wasting occurs in pathophysiological response to Cushing's syndrome. The forkhead box (FOX) protein family has been implicated as a key regulator of muscle loss under conditions such as diabetes and sepsis. However, the mechanistic role of the FOXO family in ACTH-induced muscle atrophy is not understood. We hypothesized that FOXO3a plays a role in muscle atrophy through expression of the E3 ubiquitin ligases, muscle RING finger protein-1 (MuRF-1), and atrogin-1 in Cushing's syndrome. For establishment of a Cushing's syndrome animal model, Sprague-Dawley rats were implanted with osmotic minipumps containing ACTH (40 ng·kg -1 ·day -1 ). ACTH infusion significantly reduced muscle weight. In ACTH-infused rats, MuRF-1, atrogin-1, and FOXO3a were upregulated and the FOXO3a promoter was targeted by the glucocorticoid receptor (GR). Transcriptional activity and expression of FOXO3a were significantly decreased by the GR antagonist RU486. Treatment with RU486 reduced MuRF-1 and atrogin-1 expression in accordance with reduced enrichment of FOXO3a and Pol II on the promoters. Knockdown of FOXO3a prevented dexamethasone-induced MuRF-1 and atrogin-1 expression. These results indicate that FOXO3a plays a role in muscle atrophy through expression of MuRF-1 and atrogin-1 in Cushing's syndrome. Copyright © 2017 the American Physiological Society.

Gene Expression Profiles in Parkinson Disease Prefrontal Cortex Implicate FOXO1 and Genes under Its Transcriptional Regulation

PubMed Central

Dumitriu, Alexandra; Latourelle, Jeanne C.; Hadzi, Tiffany C.; Pankratz, Nathan; Garza, Dan; Miller, John P.; Vance, Jeffery M.; Foroud, Tatiana; Beach, Thomas G.; Myers, Richard H.

2012-01-01

Parkinson disease (PD) is a complex neurodegenerative disorder with largely unknown genetic mechanisms. While the degeneration of dopaminergic neurons in PD mainly takes place in the substantia nigra pars compacta (SN) region, other brain areas, including the prefrontal cortex, develop Lewy bodies, the neuropathological hallmark of PD. We generated and analyzed expression data from the prefrontal cortex Brodmann Area 9 (BA9) of 27 PD and 26 control samples using the 44K One-Color Agilent 60-mer Whole Human Genome Microarray. All samples were male, without significant Alzheimer disease pathology and with extensive pathological annotation available. 507 of the 39,122 analyzed expression probes were different between PD and control samples at false discovery rate (FDR) of 5%. One of the genes with significantly increased expression in PD was the forkhead box O1 (FOXO1) transcription factor. Notably, genes carrying the FoxO1 binding site were significantly enriched in the FDR–significant group of genes (177 genes covered by 189 probes), suggesting a role for FoxO1 upstream of the observed expression changes. Single-nucleotide polymorphisms (SNPs) selected from a recent meta-analysis of PD genome-wide association studies (GWAS) were successfully genotyped in 50 out of the 53 microarray brains, allowing a targeted expression–SNP (eSNP) analysis for 52 SNPs associated with PD affection at genome-wide significance and the 189 probes from FoxO1 regulated genes. A significant association was observed between a SNP in the cyclin G associated kinase (GAK) gene and a probe in the spermine oxidase (SMOX) gene. Further examination of the FOXO1 region in a meta-analysis of six available GWAS showed two SNPs significantly associated with age at onset of PD. These results implicate FOXO1 as a PD–relevant gene and warrant further functional analyses of its transcriptional regulatory mechanisms. PMID:22761592

Linking diet to acne metabolomics, inflammation, and comedogenesis: an update.

PubMed

Melnik, Bodo C

2015-01-01

Acne vulgaris, an epidemic inflammatory skin disease of adolescence, is closely related to Western diet. Three major food classes that promote acne are: 1) hyperglycemic carbohydrates, 2) milk and dairy products, 3) saturated fats including trans-fats and deficient ω-3 polyunsaturated fatty acids (PUFAs). Diet-induced insulin/insulin-like growth factor (IGF-1)-signaling is superimposed on elevated IGF-1 levels during puberty, thereby unmasking the impact of aberrant nutrigenomics on sebaceous gland homeostasis. Western diet provides abundant branched-chain amino acids (BCAAs), glutamine, and palmitic acid. Insulin and IGF-1 suppress the activity of the metabolic transcription factor forkhead box O1 (FoxO1). Insulin, IGF-1, BCAAs, glutamine, and palmitate activate the nutrient-sensitive kinase mechanistic target of rapamycin complex 1 (mTORC1), the key regulator of anabolism and lipogenesis. FoxO1 is a negative coregulator of androgen receptor, peroxisome proliferator-activated receptor-γ (PPARγ), liver X receptor-α, and sterol response element binding protein-1c (SREBP-1c), crucial transcription factors of sebaceous lipogenesis. mTORC1 stimulates the expression of PPARγ and SREBP-1c, promoting sebum production. SREBP-1c upregulates stearoyl-CoA- and Δ6-desaturase, enhancing the proportion of monounsaturated fatty acids in sebum triglycerides. Diet-mediated aberrations in sebum quantity (hyperseborrhea) and composition (dysseborrhea) promote Propionibacterium acnes overgrowth and biofilm formation with overexpression of the virulence factor triglyceride lipase increasing follicular levels of free palmitate and oleate. Free palmitate functions as a "danger signal," stimulating toll-like receptor-2-mediated inflammasome activation with interleukin-1β release, Th17 differentiation, and interleukin-17-mediated keratinocyte proliferation. Oleate stimulates P. acnes adhesion, keratinocyte proliferation, and comedogenesis via interleukin-1α release. Thus, diet-induced metabolomic alterations promote the visible sebofollicular inflammasomopathy acne vulgaris. Nutrition therapy of acne has to increase FoxO1 and to attenuate mTORC1/SREBP-1c signaling. Patients should balance total calorie uptake and restrict refined carbohydrates, milk, dairy protein supplements, saturated fats, and trans-fats. A paleolithic-like diet enriched in vegetables and fish is recommended. Plant-derived mTORC1 inhibitors and ω-3-PUFAs are promising dietary supplements supporting nutrition therapy of acne vulgaris.

Linking diet to acne metabolomics, inflammation, and comedogenesis: an update

PubMed Central

Melnik, Bodo C

2015-01-01

Acne vulgaris, an epidemic inflammatory skin disease of adolescence, is closely related to Western diet. Three major food classes that promote acne are: 1) hyperglycemic carbohydrates, 2) milk and dairy products, 3) saturated fats including trans-fats and deficient ω-3 polyunsaturated fatty acids (PUFAs). Diet-induced insulin/insulin-like growth factor (IGF-1)-signaling is superimposed on elevated IGF-1 levels during puberty, thereby unmasking the impact of aberrant nutrigenomics on sebaceous gland homeostasis. Western diet provides abundant branched-chain amino acids (BCAAs), glutamine, and palmitic acid. Insulin and IGF-1 suppress the activity of the metabolic transcription factor forkhead box O1 (FoxO1). Insulin, IGF-1, BCAAs, glutamine, and palmitate activate the nutrient-sensitive kinase mechanistic target of rapamycin complex 1 (mTORC1), the key regulator of anabolism and lipogenesis. FoxO1 is a negative coregulator of androgen receptor, peroxisome proliferator-activated receptor-γ (PPARγ), liver X receptor-α, and sterol response element binding protein-1c (SREBP-1c), crucial transcription factors of sebaceous lipogenesis. mTORC1 stimulates the expression of PPARγ and SREBP-1c, promoting sebum production. SREBP-1c upregulates stearoyl-CoA- and Δ6-desaturase, enhancing the proportion of monounsaturated fatty acids in sebum triglycerides. Diet-mediated aberrations in sebum quantity (hyperseborrhea) and composition (dysseborrhea) promote Propionibacterium acnes overgrowth and biofilm formation with overexpression of the virulence factor triglyceride lipase increasing follicular levels of free palmitate and oleate. Free palmitate functions as a “danger signal,” stimulating toll-like receptor-2-mediated inflammasome activation with interleukin-1β release, Th17 differentiation, and interleukin-17-mediated keratinocyte proliferation. Oleate stimulates P. acnes adhesion, keratinocyte proliferation, and comedogenesis via interleukin-1α release. Thus, diet-induced metabolomic alterations promote the visible sebofollicular inflammasomopathy acne vulgaris. Nutrition therapy of acne has to increase FoxO1 and to attenuate mTORC1/SREBP-1c signaling. Patients should balance total calorie uptake and restrict refined carbohydrates, milk, dairy protein supplements, saturated fats, and trans-fats. A paleolithic-like diet enriched in vegetables and fish is recommended. Plant-derived mTORC1 inhibitors and ω-3-PUFAs are promising dietary supplements supporting nutrition therapy of acne vulgaris. PMID:26203267

Comparative studies on testicular and epididymal morphology, and serum hormone concentrations in foxes and the hybrids during the breeding season.

PubMed

Yang, T A; Yang, Y H; Peng, Y H; Cong, B; Diao, Y F; Bao, K; Hu, P F; Song, X C; Liu, L L; Yang, Y F; Xing, X M; Yang, F H

2016-05-01

The silver fox and the blue fox belong to different genera, and the hybrid males are fully or partially sterile. In the present study, the objective was to evaluate the causes of hybrid male sterility, and therefore analyze the differences in testicular, and epididymal morphology and serum hormone concentrations among silver foxes, blue foxes, and the hybrids during the breeding season. Samples were collected from 20 male silver foxes, 20 male blue foxes, 15 male HSBs (silver fox female × blue fox male hybrids) and 14 male HBSs (blue fox male × silver fox female hybrids), respectively. Seminal evaluation showed large numbers of sperm present in the semen of blue foxes and silver foxes, but no sperm present in the hybrids. Mean testicular volume and the diameter of seminiferous tubules in silver foxes and blue foxes were greater than in the hybrids; and there were many Sertoli cells, spermatogenic cells, and sperm in silver foxes and blue foxes, while spermatogenic cells decreased with no sperm in the hybrids. Mean serum LH and prolactin concentrations in silver foxes and blue foxes were less and testosterone was greater than in the hybrids (P<0.05). The results indicate that germ cell meioses in the hybrids were arrested at the prophase stage of meiosis, and that lesser concentrations of testosterone and greater concentrations of LH and prolactin can inhibit the completion of spermatogenesis. Copyright © 2016 Elsevier B.V. All rights reserved.

FoxO1 controls lysosomal acid lipase in adipocytes: implication of lipophagy during nutrient restriction and metformin treatment

PubMed Central

Lettieri Barbato, D; Tatulli, G; Aquilano, K; Ciriolo, M R

2013-01-01

Finding new molecular pathways and strategies modulating lipolysis in adipocytes is an attractive goal of the current research. Indeed, it is becoming clear that several human age-related pathologies are caused by adipose tissue expansion and altered lipid metabolism. In the present work, we show that transcription factor forkhead homeobox type protein O1 (FoxO1) is upregulated by nutrient restriction (NR) in adipocytes and exerts the transcriptional control of lipid catabolism via the induction of lysosomal acid lipase (Lipa). An increased autophagy and colocalization of lipid droplets (LDs) with lysosomes was observed implying lipophagy in Lipa-mediated LDs degradation. Interestingly, we found that metformin (Metf), a biguanide drug commonly used to treat type-2 diabetes, exerts effects comparable to that of NR. Actually, it was able to elicit FoxO1-dependent Lipa induction as well as LDs degradation through lipophagy. Moreover, we demonstrate that, during NR or Metf treatment, free fatty acids released by Lipa are directed toward AMP-activated protein kinase-mediated mitochondrial oxidation, thus maintaining energetic homeostasis in adipocytes. In conclusion, our data show that lysosomal-mediated lipid catabolism is activated by NR in adipocytes and give further support to the use of Metf as a NR mimetic to combat age-related diseases associated with altered lipid metabolism. PMID:24136225

Selective amputation of the pharynx identifies a FoxA-dependent regeneration program in planaria

PubMed Central

Adler, Carolyn E; Seidel, Chris W; McKinney, Sean A; Sánchez Alvarado, Alejandro

2014-01-01

Planarian flatworms regenerate every organ after amputation. Adult pluripotent stem cells drive this ability, but how injury activates and directs stem cells into the appropriate lineages is unclear. Here we describe a single-organ regeneration assay in which ejection of the planarian pharynx is selectively induced by brief exposure of animals to sodium azide. To identify genes required for pharynx regeneration, we performed an RNAi screen of 356 genes upregulated after amputation, using successful feeding as a proxy for regeneration. We found that knockdown of 20 genes caused a wide range of regeneration phenotypes and that RNAi of the forkhead transcription factor FoxA, which is expressed in a subpopulation of stem cells, specifically inhibited regrowth of the pharynx. Selective amputation of the pharynx therefore permits the identification of genes required for organ-specific regeneration and suggests an ancient function for FoxA-dependent transcriptional programs in driving regeneration. DOI: http://dx.doi.org/10.7554/eLife.02238.001 PMID:24737865

Behavioral interactions of penned red and arctic foxes

USGS Publications Warehouse

Rudzinski, D.R.; Graves, H.B.; Sargeant, A.B.; Storm, G.L.

1982-01-01

Expansion of the geographical distribution of red foxes (Vulpes vulpes) into the far north tundra region may lead to competition between arctic (Alopex lagopus) and red foxes for space and resources. Behavioral interactions between red and arctic foxes were evaluated during 9 trials conducted in a 4.05-ha enclosure near Woodworth, North Dakota. Each trial consisted of introducing a male-female pair of arctic foxes into the enclosure and allowing them to acclimate for approximately a week before releasing a female red fox into the enclosure, followed by her mate a few days later. In 8 of 9 trials, red foxes were dominant over arctic foxes during encounters. Activity of the arctic foxes decreased upon addition of red foxes. Arctic foxes tried unsuccessfully to defend preferred den, resting, and feeding areas. Even though the outcome of competition between red and arctic foxes in the Arctic is uncertain, the more aggressive red fox can dominate arctic foxes in direct competition for den sites and other limited resources.

Molecular Pathology of Adult T-Cell Leukemia/Lymphoma.

PubMed

Ohshima, Koichi

2015-01-01

Adult T-cell leukemia/lymphoma (ATLL) is a peripheral T-cell neoplasm of highly pleomorphic lymphoid cells. ATLL is usually widely disseminated, and it is caused by human T-cell leukemia virus type 1 (HTLV-1). It is a disease with a long latency, and affected individuals are usually exposed to the virus very early in life. The cumulative incidence of ATLL is estimated to be 2.5% among HTLV-1 carriers. ATLL cells express CD2, CD3, CD5, CD4, and CD25, as well as CCR4 and FoxP3 of the regulatory T-cell marker. HTLV-1 is causally linked to ATLL, but infection alone is not sufficient to result in neoplastic transformation. A significant finding in this connection is that the Tax viral protein leads to transcriptional activation of many genes, while the HTLV-1 basic leucine zipper factor is thought to be important for T-cell proliferation and oncogenesis. Half of ATLL cases retain the ability to express HTLV-1 Tax, which is a target of HTLV-1-specific cytotoxic T lymphocytes (CTL). An increase in HTLV-1-specific CTL responses is observed in some asymptomatic HTLV-1 carriers. Although HTLV-1-specific CTL are also present in the peripheral blood of ATLL patients, they do not expand sufficiently. We investigated the clinicopathological features and analyzed the staining of Tax-specific CTL and FoxP3. Tax-specific CTL correlated inversely with FoxP3, an increase in the ratio of CD163+ tumor-associated macrophages was associated with worse clinical prognosis, and ATLL cell lines proliferated significantly following direct co-culture with M2 macrophages. Several clinical variants of ATLL have been identified: acute, lymphomatous, chronic, and smoldering. Oligo-array comparative genomic hybridization revealed that genomic loss of 9p21.3 was a significant characteristic of acute-type, but not of chronic-type ATLL. Furthermore, we found that genomic alteration of CD58, which is implicated in immune escape, is more frequently observed in acute than in chronic ATLL. Interestingly, the chronic cases with cell cycle deregulation and disruption of immunosurveillance mechanism were associated with faster progression to acute ATLL. Immune evasion, microenvironment, and genetic alteration are therefore important in the multi-step progression of ATLL lymphomagenesis. © 2015 S. Karger AG, Basel.

Tumor-Associated Macrophages Recruit CCR6+ Regulatory T Cells and Promote the Development of Colorectal Cancer via Enhancing CCL20 Production in Mice

PubMed Central

Li, Qun; Zhang, Weiwei; Ke, Fang; Leng, Qibin; Wang, Hong; Chen, Jinfei; Wang, Honglin

2011-01-01

Background Tumor-associated macrophages (TAMs) remodel the colorectal cancer (CRC) microenvironment. Yet, findings on the role of TAMs in CRC seem to be contradictory compared with other cancers. FoxP3+ regulatory T (Treg)-cells dominantly infiltrate CRC. However, the underlying molecular mechanism in which TAMs may contribute to the trafficking of Treg-cells to the tumor mass remains unknown. Methodology/Principal Findings CRC was either induced by N-methyl-N-nitrosourea (MNU) and H. pylori or established by subcutaneous injection of mouse colorectal tumor cell line (CMT93) in mice. CMT93 cells were co-cultured with primary macrophages in a transwell apparatus. Recruitment of FoxP3 green fluorescence protein positive (FoxP3GFP+) Treg-cells was assessed using the IVIS Imaging System or immunofluorescence staining. A role for macrophages in trafficking of Treg-cells and in the development of CRC was investigated in CD11b diphtheria toxin receptor (CD11b-DTR) transgenic C57BL/6J mice in which macrophages can be selectively depleted. Treg-cells remarkably infiltrated solid tumor, and predominantly expressed the homing chemokine receptor (CCR) 6 in the induced CRC model. Both CMT93 cancer cells and macrophages produced a large amount of CCL20, the sole ligand of CCR6 in vitro and in vivo. Injection of recombinant mouse CCL20 into tumor sites promoted its development with a marked recruitment of Treg-cells in the graft CRC model. Conditional macrophage ablation decreased CCL20 levels, blocked Treg-cell recruitment and inhibited tumor growth in CD11b-DTR mice grafted with CMT93. Conclusions/Significance TAMs recruit CCR6+ Treg-cells to tumor mass and promote its development via enhancing the production of CCL20 in a CRC mouse model. PMID:21559338

Rapid diversification of FoxP2 in teleosts through gene duplication in the teleost-specific whole genome duplication event.

PubMed

Song, Xiaowei; Wang, Yajun; Tang, Yezhong

2013-01-01

As one of the most conserved genes in vertebrates, FoxP2 is widely involved in a number of important physiological and developmental processes. We systematically studied the evolutionary history and functional adaptations of FoxP2 in teleosts. The duplicated FoxP2 genes (FoxP2a and FoxP2b), which were identified in teleosts using synteny and paralogon analysis on genome databases of eight organisms, were probably generated in the teleost-specific whole genome duplication event. A credible classification with FoxP2, FoxP2a and FoxP2b in phylogenetic reconstructions confirmed the teleost-specific FoxP2 duplication. The unavailability of FoxP2b in Danio rerio suggests that the gene was deleted through nonfunctionalization of the redundant copy after the Otocephala-Euteleostei split. Heterogeneity in evolutionary rates among clusters consisting of FoxP2 in Sarcopterygii (Cluster 1), FoxP2a in Teleostei (Cluster 2) and FoxP2b in Teleostei (Cluster 3), particularly between Clusters 2 and 3, reveals asymmetric functional divergence after the gene duplication. Hierarchical cluster analyses of hydrophobicity profiles demonstrated significant structural divergence among the three clusters with verification of subsequent stepwise discriminant analysis, in which FoxP2 of Leucoraja erinacea and Lepisosteus oculatus were classified into Cluster 1, whereas FoxP2b of Salmo salar was grouped into Cluster 2 rather than Cluster 3. The simulated thermodynamic stability variations of the forkhead box domain (monomer and homodimer) showed remarkable divergence in FoxP2, FoxP2a and FoxP2b clusters. Relaxed purifying selection and positive Darwinian selection probably were complementary driving forces for the accelerated evolution of FoxP2 in ray-finned fishes, especially for the adaptive evolution of FoxP2a and FoxP2b in teleosts subsequent to the teleost-specific gene duplication.

Rapid Diversification of FoxP2 in Teleosts through Gene Duplication in the Teleost-Specific Whole Genome Duplication Event

PubMed Central

Song, Xiaowei; Wang, Yajun; Tang, Yezhong

2013-01-01

As one of the most conserved genes in vertebrates, FoxP2 is widely involved in a number of important physiological and developmental processes. We systematically studied the evolutionary history and functional adaptations of FoxP2 in teleosts. The duplicated FoxP2 genes (FoxP2a and FoxP2b), which were identified in teleosts using synteny and paralogon analysis on genome databases of eight organisms, were probably generated in the teleost-specific whole genome duplication event. A credible classification with FoxP2, FoxP2a and FoxP2b in phylogenetic reconstructions confirmed the teleost-specific FoxP2 duplication. The unavailability of FoxP2b in Danio rerio suggests that the gene was deleted through nonfunctionalization of the redundant copy after the Otocephala-Euteleostei split. Heterogeneity in evolutionary rates among clusters consisting of FoxP2 in Sarcopterygii (Cluster 1), FoxP2a in Teleostei (Cluster 2) and FoxP2b in Teleostei (Cluster 3), particularly between Clusters 2 and 3, reveals asymmetric functional divergence after the gene duplication. Hierarchical cluster analyses of hydrophobicity profiles demonstrated significant structural divergence among the three clusters with verification of subsequent stepwise discriminant analysis, in which FoxP2 of Leucoraja erinacea and Lepisosteus oculatus were classified into Cluster 1, whereas FoxP2b of Salmo salar was grouped into Cluster 2 rather than Cluster 3. The simulated thermodynamic stability variations of the forkhead box domain (monomer and homodimer) showed remarkable divergence in FoxP2, FoxP2a and FoxP2b clusters. Relaxed purifying selection and positive Darwinian selection probably were complementary driving forces for the accelerated evolution of FoxP2 in ray-finned fishes, especially for the adaptive evolution of FoxP2a and FoxP2b in teleosts subsequent to the teleost-specific gene duplication. PMID:24349554

Exclusion by interference competition? The relationship between red and arctic foxes.

PubMed

Tannerfeldt, Magnus; Elmhagen, Bodil; Angerbjörn, Anders

2002-07-01

The distribution of many predators may be limited by interactions with larger predator species. The arctic fox in mainland Europe is endangered, while the red fox is increasing its range in the north. It has been suggested that the southern distribution limit of the arctic fox is determined by interspecific competition with the red fox. This has been criticised, on the basis that the species co-exist on a regional scale. However, if the larger red fox is superior and interspecific competition important, the arctic fox should avoid close contact, especially during the breeding season. Consequently, the distribution of breeding dens for the two species would be segregated on a much smaller spatial and temporal scale, in areas where they are sympatric. We tested this hypothesis by analysing den use of reproducing arctic and red foxes over 9 years in Sweden. High quality dens were inhabited by reproducing arctic foxes more often when no red foxes bred in the vicinity. Furthermore, in two out of three cases when arctic foxes did reproduce near red foxes, juveniles were killed by red foxes. We also found that breeding arctic foxes occupied dens at higher altitudes than red foxes did. In a large-scale field experiment, red foxes were removed, but the results were not conclusive. However, we conclude that on the scale of individual territories, arctic foxes avoid areas with red foxes. Through interspecific interference competition, the red fox might thus be excluding the arctic fox from breeding in low altitude habitat, which is most important in years when food abundance is limited and competition is most fierce. With high altitude refuges being less suitable, even small-scale behavioural effects could scale up to significant effects at the population level.

Tissue-specific expression of FoxD reporter constructs in amphioxus embryos.

PubMed

Yu, Jr-Kai; Holland, Nicholas D; Holland, Linda Z

2004-10-15

Cephalochordates (amphioxus), the closest living invertebrate relatives of the vertebrates, are key to understanding the evolution of developmental mechanisms during the invertebrate-to-vertebrate transition. However, a major impediment to amphioxus as a model organism for developmental biology has been the inability to introduce transgenes or other macromolecules into the embryos. Here, we report the development of a reproducible method for microinjection of amphioxus eggs. Specifically, we show that expression of a LacZ reporter construct including 6.3 kb of AmphiFoxD upstream regulatory DNA recapitulates expression of the endogenous gene in the nerve cord, somites, and notochord. We have also identified the 1.6 kb at the 5' end of this region as essential for expression in the first two of these domains and the 4.7 kb at the 3' end as sufficient for expression in the notochord. This study, which is the first report of a method for introduction of large molecules such as DNA into amphioxus embryos, opens the way for studies of gene regulation and function in amphioxus and for comparative studies with vertebrates to understand the relationship between the extensive gene duplications that occurred within the vertebrate lineage and the evolution of vertebrate innovations such as neural crest.

Dietary Indoles Suppress Delayed-Type Hypersensitivity by Inducing a Switch from Pro-inflammatory Th17 cells to Anti-inflammatory Tregs through Regulation of microRNA

PubMed Central

Singh, Narendra P.; Singh, Udai P.; Rouse, Michael; Zhang, Jiajia; Chatterjee, Saurabh; Nagarkatti, Prakash S.; Nagarkatti, Mitzi

2015-01-01

Aryl hydrocarbon receptor (AhR) has been shown to have profound influence on T cell differentiation and use of distinct AhR ligands has shown that while some ligands induce Tregs, others induce Th17 cells. In the current study, we tested the ability of dietary AhR ligands (indole-3-carbinol; I3C and 3,3'-diindolylmethane; DIM), and an endogenous AhR ligand, 6-Formylindolo(3,2-b)carbazole (FICZ), on the differentiation and functions of Tregs and Th17 cells. Treatment of C57BL/6 mice with indoles (I3C or DIM), attenuated DTH response to mBSA and generation of Th17 cells while promoting Tregs. In contrast, FICZ exacerbated the DTH response and promoted Th17 cells. Indoles decreased the induction of IL-17 while promoted IL-10 and FoxP3 expression. Also, indoles caused reciprocal induction of Tregs and Th17 cells only in wild-type (AhR+/+) but not in AhR knockout (AhR−/−) mice. Upon analysis of microRNA (miR) profile in draining lymph nodes of mice with DTH, treatment with I3C and DIM decreased the expression of several miRs (miR-31, miR-219, and miR-490) that targeted FoxP3, while increasing the expression of miR-495 and miR-1192 that were specific to IL-17. Interestingly, treatment with FICZ had precisely the opposite effects on these miRs. Transfection studies using mature miR mimics of miR-490 and miR-1192 that target FoxP3 and IL-17 respectively or scrambled miR (mock) or inhibitors confirmed that these miRs specifically targeted FoxP3 and IL-17 genes. Our studies demonstrate for the first time that the ability of AhR ligands to regulate the differentiation of Tregs versus Th17 cells may depend on miR signature profile. PMID:26712945

Identification of key genes and pathways associated with neuropathic pain in uninjured dorsal root ganglion by using bioinformatic analysis.

PubMed

Chen, Chao-Jin; Liu, De-Zhao; Yao, Wei-Feng; Gu, Yu; Huang, Fei; Hei, Zi-Qing; Li, Xiang

2017-01-01

Neuropathic pain is a complex chronic condition occurring post-nervous system damage. The transcriptional reprogramming of injured dorsal root ganglia (DRGs) drives neuropathic pain. However, few comparative analyses using high-throughput platforms have investigated uninjured DRG in neuropathic pain, and potential interactions among differentially expressed genes (DEGs) and pathways were not taken into consideration. The aim of this study was to identify changes in genes and pathways associated with neuropathic pain in uninjured L4 DRG after L5 spinal nerve ligation (SNL) by using bioinformatic analysis. The microarray profile GSE24982 was downloaded from the Gene Expression Omnibus database to identify DEGs between DRGs in SNL and sham rats. The prioritization for these DEGs was performed using the Toppgene database followed by gene ontology and pathway enrichment analyses. The relationships among DEGs from the protein interactive perspective were analyzed using protein-protein interaction (PPI) network and module analysis. Real-time polymerase chain reaction (PCR) and Western blotting were used to confirm the expression of DEGs in the rodent neuropathic pain model. A total of 206 DEGs that might play a role in neuropathic pain were identified in L4 DRG, of which 75 were upregulated and 131 were downregulated. The upregulated DEGs were enriched in biological processes related to transcription regulation and molecular functions such as DNA binding, cell cycle, and the FoxO signaling pathway. Ctnnb1 protein had the highest connectivity degrees in the PPI network. The in vivo studies also validated that mRNA and protein levels of Ctnnb1 were upregulated in both L4 and L5 DRGs. This study provides insight into the functional gene sets and pathways associated with neuropathic pain in L4 uninjured DRG after L5 SNL, which might promote our understanding of the molecular mechanisms underlying the development of neuropathic pain.

Effects of roadside habitat and fox density on a snow track survey for foxes in Ohio

USGS Publications Warehouse

Stanley, Thomas R.; Bart, Jonathan

1991-01-01

Many methods have been used to survey red fox (Vulpes vulpes) and gray fox (Urocyon dnereoargenteus) populations. However, none has proven entirely satisfactory, and wild foxes remain one of the most difficult economically important wildlife species to monitor. In this study we evaluated the reliability of a snow track survey method for foxes by investigating whether the average number of road crossings per fox is influenced by changes in roadside habitat or changes in fox density. Several snow track surveys were conducted in two Ohio counties during January and February, 1984. Data on roadside habitat, relative fox densities, and fox crossings were collected. Results suggested that changes in roadside habitat could influence the average number of crossings per fox and, therefore, changes in the index could occur independent of actual population changes. We found no evidence that crossings per fox varied with fox density, but further research is needed to substantiate this finding.

Muscle cell atrophy induced by HSP gene silencing was counteracted by HSP overexpression

NASA Astrophysics Data System (ADS)

Choi, Inho; Lee, Joo-Hee; Nikawa, Takeshi; Gwag, Taesik; Park, Kyoungsook; Park, Junsoo

Heat shock proteins (HSP), as molecular chaperones, are known to assist protein quality control under various stresses. Although overexpression of HSP70 was found to contribute to muscle size retention under an unloading condition, it remains largely unclarified whether muscle atrophy is induced by active suppression of HSP expression. In this study, we pre-treated Hsp70 siRNA to rat L6 cells for the HSP gene silencing, and determined myotube diameter, HSP72 expression and anabolic and catabolic signaling activities in the absence or presence of triterpene celastrol (CEL), the HSP70 inducer. Relative to a negative control (NC), muscle cell diameter was reduced 0.89-fold in the siRNA-treated group, increased 1.2-fold in the CEL-treated group and retained at the size of NC in the siRNA+CEL group. HSP72 expression was decreased 0.35-fold by siRNA whereas the level was increased 6- to 8-fold in the CEL and siRNA+CEL groups. Expression of FoxO3 and atrogin-1 was increased 1.8- to 4.8-fold by siRNA, which was abolished by CEL treatment. Finally, phosphorylation of Akt1, S6K and ERK1/2 was not affected by siRNA, but was elevated 2- to 6-fold in the CEL and siRNA+CEL groups. Taken together, HSP downregulation by Hsp gene silencing led to muscle cell atrophy principally via increases in catabolic activities and that such anti-atrophic effect was counteracted by HSP overexpression.

Pachymic acid promotes induction of autophagy related to IGF-1 signaling pathway in WI-38 cells.

PubMed

Lee, Su-Gyeong; Kim, Moon-Moo

2017-12-01

The insulin-like growth factor 1 (IGF-1) signaling pathway has spotlighted as a mechanism to elucidate aging associated with autophagy in recent years. Therefore, we have tried to screen an effective compound capable of inducing autophagy to delay aging process. The aim of this study is to investigate whether pachymic acid, a main compound in Poria cocos, induces autophagy in the aged cells. The aging of young cells was induced by treatment with IGF-1 at 50 ng/ml three times every two days. The effect of pachymic acid on cell viability was evaluated in human lung fibroblasts, WI-38 cells, using MTT assay. The induction of autophagy was detected using autophagy detection kit. The expression of proteins related to autophagy and IGF-1 signaling pathway was examined by western blot analysis and immunofluorescence assay. In this study, pachymic acid showed cytotoxic effect in a dose dependent manner and remarkably induced autophagy at the same time. Moreover, pachymic acid increased the expression of proteins related to autophagy such as LC3-II and Beclin1 and decreased the levels of mTor phosphorylation and p70S6K in the aged cells. In particular, pachymic acid increased the expression of p-PI3K, p-FoxO and Catalase. In addition, pachymic acid remarkably increased the expression of IGFBP-3. Above results suggest that pachymic acid could induce autophagy related to IGF-1 signaling pathway in the aged cells. Copyright © 2017 Elsevier GmbH. All rights reserved.

Comparative Analysis of mRNA Isoform Expression in Cardiac Hypertrophy and Development Reveals Multiple Post-Transcriptional Regulatory Modules

PubMed Central

Park, Ji Yeon; Li, Wencheng; Zheng, Dinghai; Zhai, Peiyong; Zhao, Yun; Matsuda, Takahisa; Vatner, Stephen F.; Sadoshima, Junichi; Tian, Bin

2011-01-01

Cardiac hypertrophy is enlargement of the heart in response to physiological or pathological stimuli, chiefly involving growth of myocytes in size rather than in number. Previous studies have shown that the expression pattern of a group of genes in hypertrophied heart induced by pressure overload resembles that at the embryonic stage of heart development, a phenomenon known as activation of the “fetal gene program”. Here, using a genome-wide approach we systematically defined genes and pathways regulated in short- and long-term cardiac hypertrophy conditions using mice with transverse aortic constriction (TAC), and compared them with those regulated at different stages of embryonic and postnatal development. In addition, exon-level analysis revealed widespread mRNA isoform changes during cardiac hypertrophy resulting from alternative usage of terminal or internal exons, some of which are also developmentally regulated and may be attributable to decreased expression of Fox-1 protein in cardiac hypertrophy. Genes with functions in certain pathways, such as cell adhesion and cell morphology, are more likely to be regulated by alternative splicing. Moreover, we found 3′UTRs of mRNAs were generally shortened through alternative cleavage and polyadenylation in hypertrophy, and microRNA target genes were generally de-repressed, suggesting coordinated mechanisms to increase mRNA stability and protein production during hypertrophy. Taken together, our results comprehensively delineated gene and mRNA isoform regulation events in cardiac hypertrophy and revealed their relations to those in development, and suggested that modulation of mRNA isoform expression plays an importance role in heart remodeling under pressure overload. PMID:21799842

Alpha-lipoic acid improves high-fat diet-induced hepatic steatosis by modulating the transcription factors SREBP-1, FoxO1 and Nrf2 via the SIRT1/LKB1/AMPK pathway.

PubMed

Yang, Yi; Li, Wang; Liu, Yang; Sun, Yuning; Li, Yan; Yao, Qing; Li, Jianning; Zhang, Qian; Gao, Yujing; Gao, Ling; Zhao, Jiajun

2014-11-01

Understanding the mechanism by which alpha-lipoic acid supplementation has a protective effect upon nonalcoholic fatty liver disease in vivo and in vitro may lead to targets for preventing hepatic steatosis. Male C57BL/6J mice were fed a normal diet, high-fat diet or high-fat diet supplemented with alpha-lipoic acid for 24 weeks. HepG2 cells were incubated with normal medium, palmitate or alpha-lipoic acid. The lipid-lowering effects were measured. The protein expression and distribution were analyzed by Western blot, immunoprecipitation and immunofluorescence, respectively. We found that alpha-lipoic acid enhanced sirtuin 1 deacetylase activity through liver kinase B1 and stimulated AMP-activated protein kinase. By activating the sirtuin 1/liver kinase B1/AMP-activated protein kinase pathway, the translocation of sterol regulatory element-binding protein-1 into the nucleus and forkhead box O1 into the cytoplasm was prevented. Alpha-lipoic acid increased adipose triacylglycerol lipase expression and decreased fatty acid synthase abundance. In in vivo and in vitro studies, alpha-lipoic acid also increased nuclear NF-E2-related factor 2 levels and downstream target amounts via the sirtuin 1 pathway. Alpha-lipoic acid eventually reduced intrahepatic and serum triglyceride content. The protective effects of alpha-lipoic acid on hepatic steatosis appear to be associated with the transcription factors sterol regulatory element-binding protein-1, forkhead box O1 and NF-E2-related factor 2. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

Obestatin controls the ubiquitin–proteasome and autophagy–lysosome systems in glucocorticoid‐induced muscle cell atrophy

PubMed Central

Cid‐Díaz, Tania; Santos‐Zas, Icía; González‐Sánchez, Jessica; Gurriarán‐Rodríguez, Uxía; Mosteiro, Carlos S.; Casabiell, Xesús; García‐Caballero, Tomás; Mouly, Vincent; Pazos, Yolanda

2017-01-01

Abstract Background Many pathological states characterized by muscle atrophy are associated with an increase in circulating glucocorticoids and poor patient prognosis, making it an important target for treatment. The development of treatments for glucocorticoid‐induced and wasting disorder‐related skeletal muscle atrophy should be designed based on how the particular transcriptional program is orchestrated and how the balance of muscle protein synthesis and degradation is deregulated. Here, we investigated whether the obestatin/GPR39 system, an autocrine/paracrine signaling system acting on myogenesis and with anabolic effects on the skeletal muscle, could protect against glucocorticoid‐induced muscle cell atrophy. Methods In the present study, we have utilized mouse C2C12 myotube cultures to examine whether the obestatin/GPR39 signaling pathways can affect the atrophy induced by the synthetic glucocorticoid dexamethasone. We have extended these findings to in vitro effects on human atrophy using human KM155C25 myotubes. Results The activation of the obestatin/GPR39 system protects from glucocorticoid‐induced atrophy by regulation of Akt, PKD/PKCμ, CAMKII and AMPK signaling and its downstream targets in the control of protein synthesis, ubiquitin–proteasome system and autophagy–lysosome system in mouse cells. We compared mouse and human myotube cells in their response to glucocorticoid and identified differences in both the triggering of the atrophic program and the response to obestatin stimulation. Notably, we demonstrate that specific patterns of post‐translational modifications of FoxO4 and FoxO1 play a key role in directing FoxO activity in response to obestatin in human myotubes. Conclusions Our findings emphasize the function of the obestatin/GPR39 system in coordinating a variety of pathways involved in the regulation of protein degradation during catabolic conditions. PMID:28675664

TGF-β1/Smad3 Pathway Targets PP2A-AMPK-FoxO1 Signaling to Regulate Hepatic Gluconeogenesis.

PubMed

Yadav, Hariom; Devalaraja, Samir; Chung, Stephanie T; Rane, Sushil G

2017-02-24

Maintenance of glucose homeostasis is essential for normal physiology. Deviation from normal glucose levels, in either direction, increases susceptibility to serious medical complications such as hypoglycemia and diabetes. Maintenance of glucose homeostasis is achieved via functional interactions among various organs: liver, skeletal muscle, adipose tissue, brain, and the endocrine pancreas. The liver is the primary site of endogenous glucose production, especially during states of prolonged fasting. However, enhanced gluconeogenesis is also a signature feature of type 2 diabetes (T2D). Thus, elucidating the signaling pathways that regulate hepatic gluconeogenesis would allow better insight into the process of normal endogenous glucose production as well as how this process is impaired in T2D. Here we demonstrate that the TGF-β1/Smad3 signaling pathway promotes hepatic gluconeogenesis, both upon prolonged fasting and during T2D. In contrast, genetic and pharmacological inhibition of TGF-β1/Smad3 signals suppressed endogenous glucose production. TGF-β1 and Smad3 signals achieved this effect via the targeting of key regulators of hepatic gluconeogenesis, protein phosphatase 2A (PP2A), AMP-activated protein kinase (AMPK), and FoxO1 proteins. Specifically, TGF-β1 signaling suppressed the LKB1-AMPK axis, thereby facilitating the nuclear translocation of FoxO1 and activation of key gluconeogenic genes, glucose-6-phosphatase and phosphoenolpyruvate carboxykinase. These findings underscore an important role of TGF-β1/Smad3 signaling in hepatic gluconeogenesis, both in normal physiology and in the pathophysiology of metabolic diseases such as diabetes, and are thus of significant medical relevance. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

TGF-β1/Smad3 Pathway Targets PP2A-AMPK-FoxO1 Signaling to Regulate Hepatic Gluconeogenesis*

PubMed Central

Yadav, Hariom; Devalaraja, Samir; Chung, Stephanie T.; Rane, Sushil G.

2017-01-01

Maintenance of glucose homeostasis is essential for normal physiology. Deviation from normal glucose levels, in either direction, increases susceptibility to serious medical complications such as hypoglycemia and diabetes. Maintenance of glucose homeostasis is achieved via functional interactions among various organs: liver, skeletal muscle, adipose tissue, brain, and the endocrine pancreas. The liver is the primary site of endogenous glucose production, especially during states of prolonged fasting. However, enhanced gluconeogenesis is also a signature feature of type 2 diabetes (T2D). Thus, elucidating the signaling pathways that regulate hepatic gluconeogenesis would allow better insight into the process of normal endogenous glucose production as well as how this process is impaired in T2D. Here we demonstrate that the TGF-β1/Smad3 signaling pathway promotes hepatic gluconeogenesis, both upon prolonged fasting and during T2D. In contrast, genetic and pharmacological inhibition of TGF-β1/Smad3 signals suppressed endogenous glucose production. TGF-β1 and Smad3 signals achieved this effect via the targeting of key regulators of hepatic gluconeogenesis, protein phosphatase 2A (PP2A), AMP-activated protein kinase (AMPK), and FoxO1 proteins. Specifically, TGF-β1 signaling suppressed the LKB1-AMPK axis, thereby facilitating the nuclear translocation of FoxO1 and activation of key gluconeogenic genes, glucose-6-phosphatase and phosphoenolpyruvate carboxykinase. These findings underscore an important role of TGF-β1/Smad3 signaling in hepatic gluconeogenesis, both in normal physiology and in the pathophysiology of metabolic diseases such as diabetes, and are thus of significant medical relevance. PMID:28069811

Endometrial immune markers are potential predictors of normal fertility and pregnancy after in vitro fertilization.

PubMed

Kofod, Louise; Lindhard, Anette; Bzorek, Michael; Eriksen, Jens Ole; Larsen, Lise Grupe; Hviid, Thomas Vauvert F

2017-09-01

Elucidating immune mechanisms in the endometrium, which lead to the success of implantation and pregnancy, is important in reproductive medicine. Studies of immune cell abundance have shown conflicting results, and the expression and importance of HLA class Ib proteins in pre-implantation endometrium have not yet been investigated. The study population consisted of four subgroups: a hydrosalpinx, a salpingectomy, an unexplained infertility, and a fertile control group. Endometrial samples were collected during the implantation window. Immune markers (CD56 + and CD16 + cells, FoxP3 + Tregs, HLA-G, HLA-F) were quantified in the samples. The outcome of the subsequent IVF treatment was recorded. Increased CD56 + uNK cells and high HLA-G expression served as predictor for successful pregnancy outcome. HLA-F expression was positively correlated with uNK cells, being indirectly predictive for achieving pregnancy. Endometrial uNK cell abundance in the pre-implantation endometrium seems to be important for normal fertility and pregnancy success, and they may be used as clinical markers to predict implantation success in IVF. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Regulation of Six1 expression by evolutionarily conserved enhancers in tetrapods.

PubMed

Sato, Shigeru; Ikeda, Keiko; Shioi, Go; Nakao, Kazuki; Yajima, Hiroshi; Kawakami, Kiyoshi

2012-08-01

The Six1 homeobox gene plays critical roles in vertebrate organogenesis. Mice deficient for Six1 show severe defects in organs such as skeletal muscle, kidney, thymus, sensory organs and ganglia derived from cranial placodes, and mutations in human SIX1 cause branchio-oto-renal syndrome, an autosomal dominant developmental disorder characterized by hearing loss and branchial defects. The present study was designed to identify enhancers responsible for the dynamic expression pattern of Six1 during mouse embryogenesis. The results showed distinct enhancer activities of seven conserved non-coding sequences (CNSs) retained in tetrapod Six1 loci. The activities were detected in all cranial placodes (excluding the lens placode), dorsal root ganglia, somites, nephrogenic cord, notochord and cranial mesoderm. The major Six1-expression domains during development were covered by the sum of activities of these enhancers, together with the previously identified enhancer for the pre-placodal region and foregut endoderm. Thus, the eight CNSs identified in a series of our study represent major evolutionarily conserved enhancers responsible for the expression of Six1 in tetrapods. The results also confirmed that chick electroporation is a robust means to decipher regulatory information stored in vertebrate genomes. Mutational analysis of the most conserved placode-specific enhancer, Six1-21, indicated that the enhancer integrates a variety of inputs from Sox, Pax, Fox, Six, Wnt/Lef1 and basic helix-loop-helix proteins. Positive autoregulation of Six1 is achieved through the regulation of Six protein-binding sites. The identified Six1 enhancers provide valuable tools to understand the mechanism of Six1 regulation and to manipulate gene expression in the developing embryo, particularly in the sensory organs. Copyright © 2012 Elsevier Inc. All rights reserved.

Molecular cloning of a novel widely expressed human 80 kDa 17 beta-hydroxysteroid dehydrogenase IV.

PubMed Central

Adamski, J; Normand, T; Leenders, F; Monté, D; Begue, A; Stéhelin, D; Jungblut, P W; de Launoit, Y

1995-01-01

Reactions of oestrogens and androgens at position C-17 are catalysed by 17 beta-hydroxysteroid dehydrogenases (17 beta-HSDs). Cloning of the cDNA of a novel human 17 beta-HSD IV and expression of its mRNA are described. A probe derived from the recently discovered porcine 17 beta-oestradiol dehydrogenase (17 beta-EDH) was used to isolate a 2.6 kb human cDNA encoding a continuous protein of 736 amino acids of high (84%) similarity to the porcine 17 beta-EDH. The calculated molecular mass of the human enzyme is 79,595 Da. Other sequence similarities shared by the two enzymes are: an N-terminal sequence which is similar to that of members of the short-chain alcohol dehydrogenase family; amino acids 343-607 which are similar to the C-terminal domains of a trifunctional Candida tropicalis enzyme and the FOX2 gene product of Saccharomyces cerevisiae; amino acids 596-736 which are similar to human sterol carrier protein 2. The previously cloned human 17 beta-HSD I, II and III are less than 25% identical with 17 beta-HSD IV. mRNA for HSD IV is a single species of 3.0 kb, present in many tissues with highest concentrations in liver, heart, prostate and testes. When over-expressed in mammalian cells, the human 17 beta-HSD IV enzyme displays a specific unidirectional oxidative 17 beta-HSD activity. Images Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:7487879

A single immunization with a recombinant canine adenovirus expressing the rabies virus G protein confers protective immunity against rabies in mice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li Jianwei; Faber, Milosz; Papaneri, Amy

2006-12-20

Rabies vaccines based on live attenuated rabies viruses or recombinant pox viruses expressing the rabies virus (RV) glycoprotein (G) hold the greatest promise of safety and efficacy, particularly for oral immunization of wildlife. However, while these vaccines induce protective immunity in foxes, they are less effective in other animals, and safety concerns have been raised for some of these vaccines. Because canine adenovirus 2 (CAV2) is licensed for use as a live vaccine for dogs and has an excellent efficacy and safety record, we used this virus as an expression vector for the RVG. The recombinant CAV2-RV G produces virusmore » titers similar to those produced by wild-type CAV2, indicating that the RVG gene does not affect virus replication. Comparison of RVG expressed by CAV2-RV G with that of vaccinia-RV G recombinant virus (V-RG) revealed similar amounts of RV G on the cell surface. A single intramuscular or intranasal immunization of mice with CAV2-RVG induced protective immunity in a dose-dependent manner, with no clinical signs or discomfort from the virus infection regardless of the route of administration or the amount of virus.« less

Electromagnetic coherence theory of laser resonator modes.

PubMed

Saastamoinen, Toni; Turunen, Jari; Tervo, Jani; Setälä, Tero; Friberg, Ari T

2005-01-01

A theory of open laser resonators is formulated within the framework of the electromagnetic coherence theory. It is shown that if only one Fox-Li mode contributes to the field at a given frequency, then the field at that frequency is necessarily completely coherent in view of the space-frequency counterpart of the recently introduced degree of coherence of electromagnetic fields [Opt. Express 11, 1137 (2003)]. It is also shown that the relation between the number of Fox-Li modes and the new degree of coherence is analogous to the relation established in the scalar theory of laser resonator modes. Difficulties that arise with the formerly introduced visibility-based definition of the electromagnetic degree of coherence are briefly discussed.

Analysis of MicroRNA Expression in Newborns with Differential Birth Weight Using Newborn Screening Cards

PubMed Central

Rodil-Garcia, Patricia; Arellanes-Licea, Elvira del Carmen; Montoya-Contreras, Angélica; Salazar-Olivo, Luis A.

2017-01-01

Birth weight is an early predictor for metabolic diseases and microRNAs (miRNAs) are proposed as fetal programming participants. To evaluate the use of dried blood spots (DBS) on newborn screening cards (NSC) as a source of analyzable miRNAs, we optimized a commercial protocol to recover total miRNA from normal birth weight (NBW, n = 17–20), low birth weight (LBW, n = 17–20) and high birth weight (macrosomia, n = 17–20) newborns and analyzed the relative expression of selected miRNAs by stem-loop RT-qPCR. The possible role of miRNAs on the fetal programming of metabolic diseases was explored by bioinformatic tools. The optimized extraction of RNA resulted in a 1.2-fold enrichment of miRNAs respect to the commercial kit. miR-33b and miR-375 were overexpressed in macrosomia 9.8-fold (p < 0.001) and 1.7-fold, (p < 0.05), respectively and miR-454-3p was overexpressed in both LBW and macrosomia (19.7-fold, p < 0.001 and 10.8-fold, p < 0.001, respectively), as compared to NBW. Potential target genes for these miRNAs are associated to cyclic-guanosine monophosphate (cGMP)-dependent protein kinase (PKG), mitogen-activated protein kinase (MAPK), type 2 diabetes, transforming growth factor-β (TGF-β)and Forkhead box O protein (FoxO) pathways. In summary, we improved a protocol for analyzing miRNAs from NSC and provide the first evidence that birth weight modifies the expression of miRNAs associated to adult metabolic dysfunctions. Our work suggests archived NSC are an invaluable resource in the search for fetal programming biomarkers. PMID:29182561

Central Sirt1 regulates body weight and energy expenditure along with the POMC-derived peptide α-MSH and the processing enzyme CPE production in diet-induced obese male rats.

PubMed

Cyr, Nicole E; Steger, Jennifer S; Toorie, Anika M; Yang, Jonathan Z; Stuart, Ronald; Nillni, Eduardo A

2015-03-01

In the periphery, the nutrient-sensing enzyme Sirtuin 1 (silent mating type information regulation 2 homolog 1 [Sirt1]) reduces body weight in diet-induced obese (DIO) rodents. However, the role of hypothalamic Sirt1 in body weight and energy balance regulation is debated. The first studies to reveal that central Sirt1 regulates body weight came from experiments in our laboratory using Sprague-Dawley rats. Central inhibition of Sirt1 decreased body weight and food intake as a result of a forkhead box protein O1 (FoxO1)-mediated increase in the anorexigenic proopiomelanocortin (POMC) and decrease in the orexigenic Agouti-related peptide in the hypothalamic arcuate nucleus. Here, we demonstrate that central inhibition of Sirt1 in DIO decreased body weight and increased energy expenditure at higher levels as compared with the lean counterpart. Brain Sirt1 inhibition in DIO increased acetylated FoxO1, which in turn increased phosphorylated FoxO1 via improved insulin/phosphorylated AKT signaling. Elevated acetylated FoxO1 and phosphorylated FoxO1 increased POMC along with the α-melanocyte-stimulating hormone (α-MSH) maturation enzyme carboxypeptidase E, which resulted in more of the bioactive POMC product α-MSH released into the paraventricular nucleus. Increased in α-MSH led to augmented TRH levels and circulating T3 levels (triiodothyronine, thyroid hormone). These results indicate that inhibiting hypothalamic Sirt1 in DIO enhances the activity of the hypothalamic-pituitary-thyroid axis, which stimulates energy expenditure. Because we show that blocking central Sirt1 causes physiological changes that promote a negative energy balance in an obese individual, our results support brain Sirt1 as a significant target for weight loss therapeutics.

Central Sirt1 regulates body weight and energy expenditure along with the POMC-derived peptide α-MSH and the processing enzyme CPE production in diet-induced obese male rats.

PubMed

Cyr, Nicole E; Steger, Jennifer S; Toorie, Anika M; Yang, Jonathan Z; Stuart, Ronald; Nillni, Eduardo A

2014-07-01

In the periphery, the nutrient-sensing enzyme Sirtuin 1 (silent mating type information regulation 2 homolog 1 [Sirt1]) reduces body weight in diet-induced obese (DIO) rodents. However, the role of Sirt1 in the brain, particularly the hypothalamus, in body weight and energy balance regulation is debated. Among the first studies to reveal that central Sirt1 regulates body weight came from experiments in our laboratory using Sprague Dawley rats. In that study, central inhibition of Sirt1 decreased body weight and food intake as a result of a Forkhead box protein O1 (FoxO1)-mediated increase in the anorexigenic proopiomelanocortin (POMC) and decrease in the orexigenic Agouti-related peptide in the hypothalamic arcuate nucleus. Here, we demonstrate that central inhibition of Sirt1 in DIO decreased body weight and increased energy expenditure at higher levels as compared with the lean counterpart. Brain Sirt1 inhibition in DIO increased acetylated FoxO1, which, in turn, increased phosphorylated FoxO1 via improved insulin/pAKT signaling. Elevated acetylated FoxO1 and phosphorylated FoxO1 increased POMC along with the α-MSH maturation enzyme carboxypeptidase E, which resulted in more of the bioactive POMC product α-MSH released into the paraventricular nucleus. Increased in α-MSH led to augmented TRH levels and circulating T3 levels (thyroid hormone). These results indicate that inhibiting hypothalamic Sirt1 in DIO enhances the activity of the hypothalamic-pituitary-thyroid axis, which stimulates energy expenditure. Because we show that blocking central Sirt1 causes physiological changes that promote a negative energy balance in an obese individual, our results support brain Sirt1 as a significant target for weight loss therapeutics.

78 FR 10631 - List of Allottees or Heirs Determined To Receive Monetary Compensation Under the White Earth...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-14

... Edsel None F534080891 A1F22 Estey, Denise Claire Bond None F534080891 A1F21 Fox, James None F534081226 A1A Fox, James None F534081226 A3 Fox, James None F534081226 A11A1 Fox, James None F534081226 A6A1 Fox, James None F534081226 A4A Fox, James None F534081226 A1B1 Fox, James None F534081226 A11A2A Fox, James...

IL-12 and IL-23 modulate plasticity of FoxP3+ regulatory T cells in human Leprosy.

PubMed

Tarique, Mohd; Saini, Chaman; Naqvi, Raza Ali; Khanna, Neena; Sharma, Alpana; Rao, D N

2017-03-01

Leprosy is a bacterial disease caused by M. leprae. Its clinical spectrum reflects the host's immune response to the M. leprae and provide an ideal model to investigate the host pathogen interaction and immunological dysregulation. Tregs are high in leprosy patients and responsible for immune suppression of the host by producing IL-10 and TGF-β cytokines. In leprosy, plasticity of Tregs remain unstudied. This is the first study describing the conversion of Tregs into Th1-like and Th17-like cells using in vitro cytokine therapy in leprosy patients. Peripheral blood mononuclear cells from leprosy patients were isolated and stimulated with M. leprae antigen (MLCwA), rIL-12 and rIL-23 for 48h. Expression of FoxP3 in CD4 + CD25 + Tregs, intracellular cytokines IFN-γ, TGF-β, IL-10 and IL-17 in Tregs cells were evaluated by flow cytometry (FACS) after stimulation. rIL-12 treatment increases the levels of pStat4 in Tregs and IFN-γ production. In the presence of rIL-23, pStat3 + and IL-17A + cells increase. rIL-12 and r-IL-23 treatment downregulated the FoxP3 expression, IL-10 and TGF-β production by Tregs and enhances the expression of co-stimulatory molecules (CD80, CD86). In conclusion rIL-12 converts Tregs into IFN-γ producing cells through STAT-4 signaling while rIL-23 converts Tregs into IL-17 producing cells through STAT-3 signaling in leprosy patients. This study may helpful to provide a new avenue to overcome the immunosuprression in leprosy patients using in vitro cytokine. Copyright © 2017 Elsevier Ltd. All rights reserved.

A phylogenetic analysis of basal metabolism, total evaporative water loss, and life-history among foxes from desert and mesic regions.

PubMed

Williams, J B; Muñoz-Garcia, A; Ostrowski, S; Tieleman, B I

2004-01-01

We measured basal metabolic rate (BMR) and total evaporative water loss (TEWL) of species of foxes that exist on the Arabian Peninsula, Blanford's fox (Vulpes cana) and two subspecies of Red fox (Vulpes vulpes). Combining these data with that on other canids from the literature, we searched for specialization of physiological traits among desert foxes using both conventional least squares regression and regressions based on phylogenetic independent contrasts. Further, we explored the consequences of reduced body size of foxes on life history parameters such as litter size and neonate mass. For Blanford's foxes, Red foxes from the central desert of Arabia, and Red foxes from the more mesic Asir mountains, body mass averaged 1,285 +/- 52 g, 1,967 +/- 289 g, and 3,060 +/- 482 g, respectively, whereas mean BMR, during summer, was 304.5 +/- 32.3 kJ/day, 418.0 +/- 32.4 kJ/day, and 724.1 +/- 120.2 kJ/day (+/- SD). An analysis of covariance with body mass as a covariate showed no statistical differences in BMR among foxes. Analysis of covariance indicated that Red fox from the Asir mountains had a higher TEWL than Red foxes from central Arabia or than Blanford's foxes also from the mountains. Comparisons of all species of desert and mesic foxes showed no significant differences in BMR, nor did desert foxes have a significantly lower BMR than other carnivores. TEWL of desert foxes was lower than other more mesic carnivores; deviations in TEWL ranged from -17.7% for the Fennec fox (Fennecus zerda) to -57.4% for the Kit fox (Vulpes velox). Although desert foxes have a BMR comparable to other more mesic species, it appears that desert foxes do have a smaller body mass, lowering overall energy requirements. We attribute this reduction in body size to the "resource limitation hypothesis" whereby natural selection favors smaller individuals in a resource-limited environment, especially during periods of severe food shortage. However, until common garden experiments are performed, developmental plasticity and acclimation cannot be ruled out as contributors to this pattern.

Human-behavioral and paleoecological implications of terminal Pleistocene fox remains at the Marmes Site (45FR50), eastern Washington state, USA

NASA Astrophysics Data System (ADS)

Lyman, R. Lee

2012-05-01

Examination of terminal Pleistocene-age fox remains from the Marmes archaeological site in southeastern Washington State (USA) reveals that a previous identification of one specimen as arctic fox (Vulpes lagopus) was incorrect. Of nearly four-dozen associated specimens, eleven, including the one originally identified as arctic fox, represent red fox (Vulpes vulpes). Cut-marked fox bones and associated stone artifacts and eyed bone needles suggest several foxes were butchered and perhaps hides sewn together. The modern environmental setting of the Marmes site is too warm for modern red fox; the prehistoric red fox remains suggest (summer) climate was cooler when those remains were deposited.

Genome organization and DNA methylation patterns of B chromosomes in the red fox and Chinese raccoon dogs.

PubMed

Bugno-Poniewierska, Monika; Solek, Przemysław; Wronski, Mariusz; Potocki, Leszek; Jezewska-Witkowska, Grażyna; Wnuk, Maciej

2014-12-01

The molecular structure of B chromosomes (Bs) is relatively well studied. Previous research demonstrates that Bs of various species usually contain two types of repetitive DNA sequences, satellite DNA and ribosomal DNA, but Bs also contain genes encoding histone proteins and many others. However, many questions remain regarding the origin and function of these chromosomes. Here, we focused on the comparative cytogenetic characteristics of the red fox and Chinese raccoon dog B chromosomes with particular attention to the distribution of repetitive DNA sequences and their methylation status. We confirmed that the small Bs of the red fox show a typical fluorescent telomeric distal signal, whereas medium-sized Bs of the Chinese raccoon dog were characterized by clusters of telomeric sequences along their length. We also found different DNA methylation patterns for the B chromosomes of both species. Therefore, we concluded that DNA methylation may maintain the transcriptional inactivation of DNA sequences localized to B chromosomes and may prevent genetic unbalancing and several negative phenotypic effects. © 2014 The Authors.

ATM Mediates pRB Function To Control DNMT1 Protein Stability and DNA Methylation

PubMed Central

Suzuki, Misa; Hayashi, Naoyuki; Kobayashi, Masahiko; Sasaki, Nobunari; Nishiuchi, Takumi; Doki, Yuichiro; Okamoto, Takahiro; Kohno, Susumu; Muranaka, Hayato; Kitajima, Shunsuke; Yamamoto, Ken-ichi

2013-01-01

The retinoblastoma tumor suppressor gene (RB) product has been implicated in epigenetic control of gene expression owing to its ability to physically bind to many chromatin modifiers. However, the biological and clinical significance of this activity was not well elucidated. To address this, we performed genetic and epigenetic analyses in an Rb-deficient mouse thyroid C cell tumor model. Here we report that the genetic interaction of Rb and ATM regulates DNMT1 protein stability and hence controls the DNA methylation status in the promoters of at least the Ink4a, Shc2, FoxO6, and Noggin genes. Furthermore, we demonstrate that inactivation of pRB promotes Tip60 (acetyltransferase)-dependent ATM activation; allows activated ATM to physically bind to DNMT1, forming a complex with Tip60 and UHRF1 (E3 ligase); and consequently accelerates DNMT1 ubiquitination driven by Tip60-dependent acetylation. Our results indicate that inactivation of the pRB pathway in coordination with aberration in the DNA damage response deregulates DNMT1 stability, leading to an abnormal DNA methylation pattern and malignant progression. PMID:23754744

78 FR 2387 - Combined Notice of Filings #1

Federal Register 2010, 2011, 2012, 2013, 2014

2013-01-11

...: 20121228-5259. Comments Due: 5 p.m. ET 1/18/13. Docket Numbers: EC13-56-000. Applicants: Fox Energy Company, LLC, Fox Energy OP, L.P., Fox River Power, LLC, Wisconsin Public Service Corporation. Description: Section 203 Application of Fox Energy Company, LLC, Fox Energy OP, L.P, Fox River Power, LLC, and...

Spatial relations between sympatric coyotes and red foxes in North Dakota

USGS Publications Warehouse

Sargeant, A.B.; Allen, S.H.; Hastings, J.O.

1987-01-01

Spatial relations between coyotes (Canis latrans) and red foxes (Vulpes vulpes) on a 360-km2 area in North Dakota were studied during 1977-78. Coyote families occupied large (mean = 61.2 km2), relatively exclusive territories that encompassed about one-half of the study area. Fox families occupied much smaller (mean = 11.9 km2), relatively exclusive, territories that overlapped perimeters of coyote territories and/or encompassed area unoccupied by coyotes. No fox family lived totally within a coyote territory, but 3 fox families lived within the 153.6-km2 home range of an unattached yearling male coyote. Both coyotes and foxes, from families with overlapping territories, tended to use their overlap areas less than was expected by amount of overlap. Encounters between radio-equipped coyotes and foxes from families with overlapping territories occurred less often than was expected by chance. Foxes living near coyotes exhibited considerable tenacity to their territories, and no monitored fox was killed by coyotes during 2,518 fox-days of radio surveillance. A hypothesis for coyote-induced fox population declines, based largely on fox avoidance mechanisms, is presented.

Equine CD4+ CD25high T cells exhibit regulatory activity by close contact and cytokine-dependent mechanisms in vitro

PubMed Central

Hamza, Eman; Gerber, Vinzenz; Steinbach, Falko; Marti, Eliane

2011-01-01

Horses are particularly prone to allergic and autoimmune diseases, but little information about equine regulatory T cells (Treg) is currently available. The aim of this study therefore was to investigate the existence of CD4+ Treg cells in horses, determine their suppressive function as well as their mechanism of action. Freshly isolated peripheral blood mononuclear cells (PBMC) from healthy horses were examined for CD4, CD25 and forkhead box P3 (FoxP3) expression. We show that equine FoxP3 is expressed constitutively by a population of CD4+ CD25+ T cells, mainly in the CD4+ CD25high subpopulation. Proliferation of CD4+ CD25− sorted cells stimulated with irradiated allogenic PBMC was significantly suppressed in co-culture with CD4+ CD25high sorted cells in a dose-dependent manner. The mechanism of suppression by the CD4+ CD25high cell population is mediated by close contact as well as interleukin (IL)-10 and transforming growth factor-β1 (TGF-β1) and probably other factors. In addition, we studied the in vitro induction of CD4+ Treg and their characteristics compared to those of freshly isolated CD4+ Treg cells. Upon stimulation with a combination of concanavalin A, TGF-β1 and IL-2, CD4+ CD25+ T cells which express FoxP3 and have suppressive capability were induced from CD4+ CD25− cells. The induced CD4+ CD25high express higher levels of IL-10 and TGF-β1 mRNA compared to the freshly isolated ones. Thus, in horses as in man, the circulating CD4+ CD25high subpopulation contains natural Treg cells and functional Treg can be induced in vitro upon appropriate stimulation. Our study provides the first evidence of the regulatory function of CD4+ CD25+ cells in horses and offers insights into ex vivo manipulation of Treg cells. PMID:21977999

Direct activation of a notochord cis-regulatory module by Brachyury and FoxA in the ascidian Ciona intestinalis.

PubMed

Passamaneck, Yale J; Katikala, Lavanya; Perrone, Lorena; Dunn, Matthew P; Oda-Ishii, Izumi; Di Gregorio, Anna

2009-11-01

The notochord is a defining feature of the chordate body plan. Experiments in ascidian, frog and mouse embryos have shown that co-expression of Brachyury and FoxA class transcription factors is required for notochord development. However, studies on the cis-regulatory sequences mediating the synergistic effects of these transcription factors are complicated by the limited knowledge of notochord genes and cis-regulatory modules (CRMs) that are directly targeted by both. We have identified an easily testable model for such investigations in a 155-bp notochord-specific CRM from the ascidian Ciona intestinalis. This CRM contains functional binding sites for both Ciona Brachyury (Ci-Bra) and FoxA (Ci-FoxA-a). By combining point mutation analysis and misexpression experiments, we demonstrate that binding of both transcription factors to this CRM is necessary and sufficient to activate transcription. To gain insights into the cis-regulatory criteria controlling its activity, we investigated the organization of the transcription factor binding sites within the 155-bp CRM. The 155-bp sequence contains two Ci-Bra binding sites with identical core sequences but opposite orientations, only one of which is required for enhancer activity. Changes in both orientation and spacing of these sites substantially affect the activity of the CRM, as clusters of identical sites found in the Ciona genome with different arrangements are unable to activate transcription in notochord cells. This work presents the first evidence of a synergistic interaction between Brachyury and FoxA in the activation of an individual notochord CRM, and highlights the importance of transcription factor binding site arrangement for its function.

MTORC1 Regulates both General Autophagy and Mitophagy Induction after Oxidative Phosphorylation Uncoupling.

PubMed

Bartolomé, Alberto; García-Aguilar, Ana; Asahara, Shun-Ichiro; Kido, Yoshiaki; Guillén, Carlos; Pajvani, Utpal B; Benito, Manuel

2017-09-11

The mechanistic target of rapamycin complex 1 (MTORC1) is a critical negative regulator of general autophagy. We hypothesized that MTORC1 may specifically regulate autophagic clearance of damaged mitochondria. To test this, we used cells lacking tuberous sclerosis complex 2 (TSC2 -/-), which show constitutive MTORC1 activation. TSC2 -/- cells show MTORC1-dependent impaired autophagic flux after chemical uncoupling of mitochondria, increased mitochondrial protein aging and accumulation of p62/SQSTM1 positive mitochondria. Mitochondrial autophagy (mitophagy) was also deficient in cells lacking TSC2, associated with altered expression of PTEN-induced kinase 1 (PINK1) and PARK2 translocation to uncoupled mitochondria, all of which were recovered by MTORC1 inhibition or expression of constitutively active FoxO1. These data prove the necessity of intact MTORC1 signaling to regulate two synergistic processes required for clearance of damaged mitochondria: 1) general autophagy initiation, and 2) PINK1/PARK2-mediated selective targeting of uncoupled mitochondria to the autophagic machinery. Copyright © 2017 American Society for Microbiology.

Prevalence of Toxoplasma gondii infection diagnosed by PCR in farmed red foxes, arctic foxes and raccoon dogs.

PubMed

Górecki, Marcin Tadeusz; Galbas, Mariola; Szwed, Katarzyna; Przysiecki, Piotr; Dullin, Piotr; Nowicki, Sławomir

2012-01-01

The aim of this study was to compare Toxoplasma gondii infection in three canid species: red fox Vulpes vulpes, arctic fox Vulpes lagopus and raccoon dog Nyctereutesprocyonoides kept at the same farm. Anal swabs were taken from 24 adult and 10 juvenile red foxes, 12 adult arctic foxes, three adult and seven juvenile raccoon dogs. Additionally, muscle samples were taken from 10 juvenile red foxes. PCR was used to detect T. gondii DNA. T. gondii infection was not detected in any of the arctic foxes; 60% ofraccoon dogs were infected; the prevalence of the parasite in material from red fox swabs was intermediate between the prevalence observed in arctic foxes and raccoon dogs. It is possible that susceptibility and immune response to the parasite differ between the three investigated canid species. T. gondii DNA was detected in muscle tissue of five young foxes. The results of this study suggest that T. gondii infection is not rare in farmed canids.

Gray Fox (Urocyon cinereoargenteus) ecology and management

USGS Publications Warehouse

Howell, Judd A.

1997-01-01

The gray fox (Urocyon cinereoargenteus) is a petite member of the family Canidae in the order Carnivora with a long muzzle and pointed ears (Samuel and Nelson 1982). The coat of the gray fox is silver gray across the back with significant amounts of rufus along the sides. This characteristic is often confused by people who see the flash of red and assume that the fox is a red fox (Vulpes vulpes). The gray fox has a black tipped tail with a dorsal black stripe that differentiates this species from the kit fox (Vulpes macrotis). The red fox has a white tipped tail. The gray fox weighs between 3-5 kg, occasionally to 7 kg. TL 800-1125, T 275-443, HF 100-150. (Jameson and Peeters 1988).

Overcoming Endocrine Resistance by Targeting ER/FoxA1/IL 8 Axis

DTIC Science & Technology

2016-10-01

INTRODUCTION Approximately 75% of breast cancers express the hormone estrogen receptor α (ER). As a critical determinant in estrogen response and oncogenic...factor of estrogen receptor α (ER)–chromatin binding and function, yet its aberration in endocrine-resistant (Endo-R) breast cancer is unknown. Here, we...positive tumors. FOXA1 | estrogen receptor | breast cancer | transcriptional reprogramming | endocrine resistance About 75% of breast cancers express

[Safety and efficacy of an antirabies vaccine consisting of recombinant vaccinia-rabies virus administered orally to the fox, dog and cat].

PubMed

Blancou, J; Artois, M; Brochier, B; Thomas, I; Pastoret, P P; Desmettre, P; Languet, B; Kiény, M P

1989-01-01

One of the most promising ways to control rabies in wildlife seems to be the distribution of bait containing an anti-rabies vaccine. So far, the most widely used vaccines were modified live viruses (SAD strain or derivatives). Nevertheless, these strains retain some pathogenicity for non-target species. A novel vaccine was proposed consisting of genetically modified vaccinia virus (strain Copenhagen, thermosensitive ts 26) expressing the foreign glycoprotein G for the rabies virus (strain ERA). Different doses of this recombinant virus were administered orally to 59 foxes (Vulpes vulpes) and their antibodies were titrated before challenge. Foxes (8/8) resisted 1 month after vaccination with 10(7) plaque forming units (PFU), or 4/4 after 18 months. Seroconversion among dogs was 4/4 after vaccination with 10(9,6) PFU and 4/4 among cats after vaccination with 10(8) PFU. These dogs (4/4) and cats (3/4) resisted the challenge 2-3 months after vaccination. This vaccine thus appears to be potent and safe in these species. Its properties are discussed.

A conserved neuronal DAF-16/FoxO plays an important role in conveying pheromone signals to elicit repulsion behavior in Caenorhabditis elegans.

PubMed

Park, Donha; Hahm, Jeong-Hoon; Park, Saeram; Ha, Go; Chang, Gyeong-Eon; Jeong, Haelim; Kim, Heekyeong; Kim, Sunhee; Cheong, Eunji; Paik, Young-Ki

2017-08-03

Animals use pheromones as a conspecific chemical language to respond appropriately to environmental changes. The soil nematode Caenorhabditis elegans secretes ascaroside pheromones throughout the lifecycle, which influences entry into dauer phase in early larvae, in addition to sexual attraction and aggregation. In adult hermaphrodites, pheromone sensory signals perceived by worms usually elicit repulsion as an initial behavioral signature. However, the molecular mechanisms underlying neuronal pheromone sensory process from perception to repulsion in adult hermaphrodites remain poorly understood. Here, we show that pheromone signals perceived by GPA-3 is conveyed through glutamatergic neurotransmission in which neuronal DAF-16/FoxO plays an important modulatory role by controlling glutaminase gene expression. We further provide evidence that this modulatory role for DAF-16/FoxO seems to be conserved evolutionarily by electro-physiological study in mouse primary hippocampal neurons that are responsible for glutamatergic neurotransmission. These findings provide the basis for understanding the nematode pheromone signaling, which seems crucial for adaptation of adult hermaphrodites to changes in environmental condition for survival.

An Iron 13S-Lipoxygenase with an α-Linolenic Acid Specific Hydroperoxidase Activity from Fusarium oxysporum

PubMed Central

Brodhun, Florian; Cristobal-Sarramian, Alvaro; Zabel, Sebastian; Newie, Julia; Hamberg, Mats; Feussner, Ivo

2013-01-01

Jasmonates constitute a family of lipid-derived signaling molecules that are abundant in higher plants. The biosynthetic pathway leading to plant jasmonates is initiated by 13-lipoxygenase-catalyzed oxygenation of α-linolenic acid into its 13-hydroperoxide derivative. A number of plant pathogenic fungi (e.g. Fusarium oxysporum) are also capable of producing jasmonates, however, by a yet unknown biosynthetic pathway. In a search for lipoxygenase in F. oxysporum, a reverse genetic approach was used and one of two from the genome predicted lipoxygenases (FoxLOX) was cloned. The enzyme was heterologously expressed in E. coli, purified via affinity chromatography, and its reaction mechanism characterized. FoxLOX was found to be a non-heme iron lipoxygenase, which oxidizes C18-polyunsaturated fatty acids to 13S-hydroperoxy derivatives by an antarafacial reaction mechanism where the bis-allylic hydrogen abstraction is the rate-limiting step. With α-linolenic acid as substrate FoxLOX was found to exhibit a multifunctional activity, because the hydroperoxy derivatives formed are further converted to dihydroxy-, keto-, and epoxy alcohol derivatives. PMID:23741422

Pivotal Advance: Heme oxygenase 1 expression by human CD4+ T cells is not sufficient for their development of immunoregulatory capacity.

PubMed

Biburger, Markus; Theiner, Gabi; Schädle, Mirjam; Schuler, Gerold; Tiegs, Gisa

2010-02-01

HO-1 is the only inducible one of three isoenzymes that catalyzes the oxidative degradation of heme. HO-1 is inducible by various cellular stress factors and exerts cytoprotective and immunomodulatory effects. Recent publications demonstrated that HO-1 is constitutively expressed by CD4(+)CD25(+) T(regs) and induced in CD4(+)CD25(-) T cells upon FoxP3 transfection. Here, we investigated whether HO-1 was essential and sufficient for human T(regs) to exert immunosuppression in vitro. PGJ(2) induced pronounced expression of HO-1 in CD4(+)CD25(-) T cells without accompanying FoxP3 induction. Treatment of CD4(+)CD25(-) T cells with PGJ(2) decreased their proliferation, whereas the HO-1 inhibitor SnPP enhanced the proliferation of HO-1-expressing T(regs), suggesting that HO-1 may modulate the proliferative capacity of T lymphocytes. HO-1 modulation by SnPP treatment of T(regs) or PGJ(2) treatment of CD4(+)CD25(-) T cells neither suppressed nor induced immune-modulatory function in these cells, respectively, as measured by responder-cell proliferation and/or IL-2 production. In summary, these data suggest that HO-1 expression by T(regs) might contribute to their typical reluctance to proliferate but does not account independently for their suppressive functions.

Traditional Chinese medicine suppresses left ventricular hypertrophy by targeting extracellular signal-regulated kinases signaling pathway in spontaneously hypertensive rats

PubMed Central

Xiong, Xingjiang; Yang, Xiaochen; Duan, Lian; Liu, Wei; Zhang, Yun; Liu, Yongmei; Wang, Pengqian; Li, Shengjie; Li, Xiaoke

2017-01-01

Chinese herbal medicine Bu-Shen-Jiang-Ya decoction (BSJYD) is reported to be beneficial for hypertension. Over expression of extracellular signal regulated kinases (ERK) pathway plays an important role in left ventricular hypertrophy (LVH). This study aimed to observe effects of BSJYD on LVH in spontaneously hypertensive rats (SHRs) and explore its possible mechanism on regulation of ERK pathway. Sixty 12-week-old SHRs were randomly allocated into 5 groups: BSJYD high dose group, middle dose group, low dose group, captopril group, and control group. Besides, a control group of Wistar-Kyoto rats was established. All rats were treated for 8 weeks. Systolic blood pressure (SBP), heart rate (HR), pathology, and left ventricular mass index (LVMI) were measured. Western blotting and Real-time PCR were used to assess the expressions of BDNF, Ras, ERK1/2, and c-fox levels. SBP and HR were significantly decreased compared with the control group and LVMI was markedly improved by BSJYD treatment in a dose-dependent manner. BSJYD inhibited the expression of BDNF, Ras, ERK1/2, and c-fox mRNA in LVH. In conclusion, BSJYD suppressed hypertension-induced cardiac hypertrophy by inhibiting the expression of ERK pathway. These changes in gene expression may be a possible mechanism by which BSJYD provides myocardial protection from hypertension. PMID:28225023

A meiotic linkage map of the silver fox, aligned and compared to the canine genome.

PubMed

Kukekova, Anna V; Trut, Lyudmila N; Oskina, Irina N; Johnson, Jennifer L; Temnykh, Svetlana V; Kharlamova, Anastasiya V; Shepeleva, Darya V; Gulievich, Rimma G; Shikhevich, Svetlana G; Graphodatsky, Alexander S; Aguirre, Gustavo D; Acland, Gregory M

2007-03-01

A meiotic linkage map is essential for mapping traits of interest and is often the first step toward understanding a cryptic genome. Specific strains of silver fox (a variant of the red fox, Vulpes vulpes), which segregate behavioral and morphological phenotypes, create a need for such a map. One such strain, selected for docility, exhibits friendly dog-like responses to humans, in contrast to another strain selected for aggression. Development of a fox map is facilitated by the known cytogenetic homologies between the dog and fox, and by the availability of high resolution canine genome maps and sequence data. Furthermore, the high genomic sequence identity between dog and fox allows adaptation of canine microsatellites for genotyping and meiotic mapping in foxes. Using 320 such markers, we have constructed the first meiotic linkage map of the fox genome. The resulting sex-averaged map covers 16 fox autosomes and the X chromosome with an average inter-marker distance of 7.5 cM. The total map length corresponds to 1480.2 cM. From comparison of sex-averaged meiotic linkage maps of the fox and dog genomes, suppression of recombination in pericentromeric regions of the metacentric fox chromosomes was apparent, relative to the corresponding segments of acrocentric dog chromosomes. Alignment of the fox meiotic map against the 7.6x canine genome sequence revealed high conservation of marker order between homologous regions of the two species. The fox meiotic map provides a critical tool for genetic studies in foxes and identification of genetic loci and genes implicated in fox domestication.

Genomic analysis of the Pacific oyster (Crassostrea gigas) reveals possible conservation of vertebrate sex determination in a mollusc.

PubMed

Zhang, Na; Xu, Fei; Guo, Ximing

2014-09-11

Despite the prevalence of sex in animal kingdom, we have only limited understanding of how sex is determined and evolved in many taxa. The mollusc Pacific oyster Crassostrea gigas exhibits complex modes of sexual reproduction that consists of protandric dioecy, sex change, and occasional hermaphroditism. This complex system is controlled by both environmental and genetic factors through unknown molecular mechanisms. In this study, we investigated genes related to sex-determining pathways in C. gigas through transcriptome sequencing and analysis of female and male gonads. Our analysis identified or confirmed novel homologs in the oyster of key sex-determining genes (SoxH or Sry-like and FoxL2) that were thought to be vertebrate-specific. Their expression profile in C. gigas is consistent with conserved roles in sex determination, under a proposed model where a novel testis-determining CgSoxH may serve as a primary regulator, directly or indirectly interacting with a testis-promoting CgDsx and an ovary-promoting CgFoxL2. Our findings plus previous results suggest that key vertebrate sex-determining genes such as Sry and FoxL2 may not be inventions of vertebrates. The presence of such genes in a mollusc with expression profiles consistent with expected roles in sex determination suggest that sex determination may be deeply conserved in animals, despite rapid evolution of the regulatory pathways that in C. gigas may involve both genetic and environmental factors. Copyright © 2014 Zhang et al.

Genomic Analysis of the Pacific Oyster (Crassostrea gigas) Reveals Possible Conservation of Vertebrate Sex Determination in a Mollusc

PubMed Central

Zhang, Na; Xu, Fei; Guo, Ximing

2014-01-01

Despite the prevalence of sex in animal kingdom, we have only limited understanding of how sex is determined and evolved in many taxa. The mollusc Pacific oyster Crassostrea gigas exhibits complex modes of sexual reproduction that consists of protandric dioecy, sex change, and occasional hermaphroditism. This complex system is controlled by both environmental and genetic factors through unknown molecular mechanisms. In this study, we investigated genes related to sex-determining pathways in C. gigas through transcriptome sequencing and analysis of female and male gonads. Our analysis identified or confirmed novel homologs in the oyster of key sex-determining genes (SoxH or Sry-like and FoxL2) that were thought to be vertebrate-specific. Their expression profile in C. gigas is consistent with conserved roles in sex determination, under a proposed model where a novel testis-determining CgSoxH may serve as a primary regulator, directly or indirectly interacting with a testis-promoting CgDsx and an ovary-promoting CgFoxL2. Our findings plus previous results suggest that key vertebrate sex-determining genes such as Sry and FoxL2 may not be inventions of vertebrates. The presence of such genes in a mollusc with expression profiles consistent with expected roles in sex determination suggest that sex determination may be deeply conserved in animals, despite rapid evolution of the regulatory pathways that in C. gigas may involve both genetic and environmental factors. PMID:25213692

Diet patterns of island foxes on San Nicolas Island relative to feral cat removal

USGS Publications Warehouse

Cypher, Brian L.; Kelly, Erica C.; Ferrara, Francesca J.; Drost, Charles A.; Westall, Tory L.; Hudgens, Brian

2017-01-01

Island foxes (Urocyon littoralis) are a species of conservation concern that occur on six of the Channel Islands off the coast of southern California. We analysed island fox diet on San Nicolas Island during 2006–12 to assess the influence of the removal of feral cats (Felis catus) on the food use by foxes. Our objective was to determine whether fox diet patterns shifted in response to the cat removal conducted during 2009–10, thus indicating that cats were competing with foxes for food items. We also examined the influence of annual precipitation patterns and fox abundance on fox diet. On the basis of an analysis of 1975 fox scats, use of vertebrate prey – deer mice (Peromyscus maniculatus), birds, and lizards – increased significantly during and after the complete removal of cats (n = 66) from the island. Deer mouse abundance increased markedly during and after cat removal and use of mice by foxes was significantly related to mouse abundance. The increase in mice and shift in item use by the foxes was consistent with a reduction in exploitative competition associated with the cat removal. However, fox abundance declined markedly coincident with the removal of cats and deer mouse abundance was negatively related to fox numbers. Also, annual precipitation increased markedly during and after cat removal and deer mouse abundance closely tracked precipitation. Thus, our results indicate that other confounding factors, particularly precipitation, may have had a greater influence on fox diet patterns.

Overexpression of tissue-nonspecific alkaline phosphatase increases the expression of neurogenic differentiation markers in the human SH-SY5Y neuroblastoma cell line.

PubMed

Graser, Stephanie; Mentrup, Birgit; Schneider, Doris; Klein-Hitpass, Ludger; Jakob, Franz; Hofmann, Christine

2015-10-01

Patients suffering from the rare hereditary disease hypophosphatasia (HPP), which is based on mutations in the ALPL gene, tend to develop central nervous system (CNS) related issues like epileptic seizures and neuropsychiatric illnesses such as anxiety and depression, in addition to well-known problems with the mineralization of bones and teeth. Analyses of the molecular role of tissue-nonspecific alkaline phosphatase (TNAP) in transgenic SH-SY5Y(TNAPhigh) neuroblastoma cells compared to SH-SY5Y(TNAPlow) cells indicate that the enzyme influences the expression levels of neuronal marker genes like RNA-binding protein, fox-1 homolog 3 (NEUN) and enolase 2, gamma neuronal (NSE) as well as microtubule-binding proteins like microtubule-associated protein 2 (MAP2) and microtubule-associated protein tau (TAU) during neurogenic differentiation. Fluorescence staining of SH-SY5Y(TNAPhigh) cells reveals TNAP localization throughout the whole length of the developed projection network and even synapsin Ι co-localization with strong TNAP signals at some spots at least at the early time points of differentiation. Additional immunocytochemical staining shows higher MAP2 expression in SH-SY5Y(TNAPhigh) cells and further a distinct up-regulation of tau and MAP2 in the course of neurogenic differentiation. Interestingly, transgenic SH-SY5Y(TNAPhigh) cells are able to develop longer cellular processes compared to control cells after stimulation with all-trans retinoic acid (RA). Current therapies for HPP prioritize improvement of the bone phenotype. Unraveling the molecular role of TNAP in extraosseous tissues, like in the CNS, will help to improve treatment strategies for HPP patients. Taking this rare disease as a model may also help to dissect TNAP's role in neurodegenerative diseases and even improve future treatment of common pathologies. Copyright © 2015 Elsevier Inc. All rights reserved.

On a Possible Evolutionary Link of the Stomochord of Hemichordates to Pharyngeal Organs of Chordates

PubMed Central

Satoh, Noriyuki; Tagawa, Kunifumi; Lowe, Christopher J.; Yu, Jr-Kai; Kawashima, Takeshi; Takahashi, Hiroki; Ogasawara, Michio; Kirschner, Marc; Hisata, Kanako; Su, Yi-Hsien; Gerhart, John

2017-01-01

Summary As a group closely related to chordates, hemichordate acorn worms are in a key phylogenic position for addressing hypotheses of chordate origins. The stomochord of acorn worms is an anterior outgrowth of the pharynx endoderm into the proboscis. In 1886 Bateson proposed homology of this organ to the chordate notochord, crowning this animal group “hemichordates.” Although this proposal has been debated for over a century, the question still remains unresolved. Here we review recent progress related to this question. First, the developmental mode of the stomochord completely differs from that of the notochord. Second, comparison of expression profiles of genes including Brachyury, a key regulator of notochord formation in chordates, does not support the stomochord/notochord homology. Third, FoxE that is expressed in the stomochord-forming region in acorn worm juveniles is expressed in the club-shaped gland and in the endostyle of amphioxus, in the endostyle of ascidians, and in the thyroid gland of vertebrates. Based on these findings, together with the anterior endodermal location of the stomochord, we propose that the stomochord has evolutionary relatedness to chordate organs deriving from the anterior pharynx rather than to the notochord. PMID:25303744

On a possible evolutionary link of the stomochord of hemichordates to pharyngeal organs of chordates.

PubMed

Satoh, Noriyuki; Tagawa, Kunifumi; Lowe, Christopher J; Yu, Jr-Kai; Kawashima, Takeshi; Takahashi, Hiroki; Ogasawara, Michio; Kirschner, Marc; Hisata, Kanako; Su, Yi-Hsien; Gerhart, John

2014-12-01

As a group closely related to chordates, hemichordate acorn worms are in a key phylogenic position for addressing hypotheses of chordate origins. The stomochord of acorn worms is an anterior outgrowth of the pharynx endoderm into the proboscis. In 1886 Bateson proposed homology of this organ to the chordate notochord, crowning this animal group "hemichordates." Although this proposal has been debated for over a century, the question still remains unresolved. Here we review recent progress related to this question. First, the developmental mode of the stomochord completely differs from that of the notochord. Second, comparison of expression profiles of genes including Brachyury, a key regulator of notochord formation in chordates, does not support the stomochord/notochord homology. Third, FoxE that is expressed in the stomochord-forming region in acorn worm juveniles is expressed in the club-shaped gland and in the endostyle of amphioxus, in the endostyle of ascidians, and in the thyroid gland of vertebrates. Based on these findings, together with the anterior endodermal location of the stomochord, we propose that the stomochord has evolutionary relatedness to chordate organs deriving from the anterior pharynx rather than to the notochord. © 2014 Wiley Periodicals, Inc.

Tumor-Infiltrating T Cells and the PD-1 Checkpoint Pathway in Advanced Differentiated and Anaplastic Thyroid Cancer

PubMed Central

Bastman, Jill J.; Serracino, Hilary S.; Zhu, Yuwen; Koenig, Michelle R.; Mateescu, Valerica; Sams, Sharon B.; Davies, Kurtis D.; Raeburn, Christopher D.; McIntyre, Robert C.; Haugen, Bryan R.

2016-01-01

Context: Five to 10% of patients with differentiated thyroid cancers (DTC) develop invasive and/or distant metastatic disease that is marginally improved with standard therapies. Prognosis is poor for patients with anaplastic thyroid cancer, with a median survival of 3–5 months. We suggest that a paradigm shift is necessary in the treatment of advanced cases. Objective: We hypothesized that a T-cell response is generated in advanced thyroid cancer and may be a viable therapeutic target. Design: Primary DTCs were analyzed by quantitative RT-PCR (n = 92) for expression of CD3, CD8, forkhead box (Fox)-P3, programmed death (PD)-1, PD-1 ligand-1, and PD-1 ligand-2 and biopsied for cellular analysis by flow cytometry (n = 11). Advanced pT4 cases (n = 22) and metastases (n = 5) were analyzed by immunohistochemistry. Setting: The study was conducted at the University of Colorado Hospital. Patients: Thyroid cancer patients undergoing thyroidectomy or completion surgery for advanced disease between 2002 and 2013 participated in the study. Intervention: There were no interventions. Main Outcome Measure: Immune markers were analyzed for association with disease severity. Results: Immune markers were commonly expressed at the RNA level. PD-L1 was higher (P = .0443) in patients with nodal metastases. FoxP3+ (P < .0001), PD-1+CD8+ (P = .0058), and PD-1+CD4+ (P = .0104) T cells were enriched in DTC biopsies. CD8+ and FoxP3+ T cells were detected by immunohistochemistry in all pT4 tumors and a subset of metastases. PD-1+ lymphocytes were found in 50% of DTCs. PD-L1 was expressed by tumor and associated leukocytes in 13 of 22 cases, and expression was more diffuse in anaplastic thyroid cancer (P = .0373). BRAFV600E mutation was associated with higher frequencies of tumor-associated lymphocytes (P = .0095) but not PD-L1 expression. Conclusions: PD-1 checkpoint blockades may have therapeutic efficacy in patients with aggressive forms of thyroid cancer. PMID:27045886

FoxO6 Integrates Insulin Signaling With Gluconeogenesis in the Liver

PubMed Central

Kim, Dae Hyun; Perdomo, German; Zhang, Ting; Slusher, Sandra; Lee, Sojin; Phillips, Brett E.; Fan, Yong; Giannoukakis, Nick; Gramignoli, Roberto; Strom, Stephen; Ringquist, Steven; Dong, H. Henry

2011-01-01

OBJECTIVE Excessive endogenous glucose production contributes to fasting hyperglycemia in diabetes. This effect stems from inept insulin suppression of hepatic gluconeogenesis. To understand the underlying mechanisms, we studied the ability of forkhead box O6 (FoxO6) to mediate insulin action on hepatic gluconeogenesis and its contribution to glucose metabolism. RESEARCH DESIGN AND METHODS We characterized FoxO6 in glucose metabolism in cultured hepatocytes and in rodent models of dietary obesity, insulin resistance, or insulin-deficient diabetes. We determined the effect of FoxO6 on hepatic gluconeogenesis in genetically modified mice with FoxO6 gain- versus loss-of-function and in diabetic db/db mice with selective FoxO6 ablation in the liver. RESULTS FoxO6 integrates insulin signaling to hepatic gluconeogenesis. In mice, elevated FoxO6 activity in the liver augments gluconeogenesis, raising fasting blood glucose levels, and hepatic FoxO6 depletion suppresses gluconeogenesis, resulting in fasting hypoglycemia. FoxO6 stimulates gluconeogenesis, which is counteracted by insulin. Insulin inhibits FoxO6 activity via a distinct mechanism by inducing its phosphorylation and disabling its transcriptional activity, without altering its subcellular distribution in hepatocytes. FoxO6 becomes deregulated in the insulin-resistant liver, accounting for its unbridled activity in promoting gluconeogenesis and correlating with the pathogenesis of fasting hyperglycemia in diabetes. These metabolic abnormalities, along with fasting hyperglycemia, are reversible by selective inhibition of hepatic FoxO6 activity in diabetic mice. CONCLUSIONS Our data uncover a FoxO6-dependent pathway by which the liver orchestrates insulin regulation of gluconeogenesis, providing the proof-of-concept that selective FoxO6 inhibition is beneficial for curbing excessive hepatic glucose production and improving glycemic control in diabetes. PMID:21940782

Osteogenesis potential of different titania nanotubes in oxidative stress microenvironment.

PubMed

Yu, Yonglin; Shen, Xinkun; Luo, Zhong; Hu, Yan; Li, Menghuan; Ma, Pingping; Ran, Qichun; Dai, Liangliang; He, Ye; Cai, Kaiyong

2018-06-01

Oxidative stress is commonly existed in bone degenerative disease (osteoarthritis, osteoporosis etc.) and some antioxidants had great potential to enhance osteogenesis. In this study, we aim to investigate the anti-oxidative properties of various TiO 2 nanotubes (TNTs) so to screen the desirable size for improved osteogenesis and reveal the underlying molecular mechanism in vitro. Comparing cellular behaviors under normal and oxidative stress conditions, an interesting conclusion was obtained. In normal microenvironment, small TNTs were beneficial for adhesion and proliferation of osteoblasts, but large TNTs greatly increased osteogenic differentiation. However, after H 2 O 2 (300 μM) treatment (mimicking oxidative stress), only large TNTs samples demonstrated superior cellular behaviors of increased osteoblasts' adhesion, survival and differentiation when comparing with those of native titanium (control). Molecular results revealed that oxidative stress resistance of large nanotubes was closely related to the high expression of integrin α5β1 (ITG α5β1), which further up-regulated the production of anti-apoptotic proteins (p-FAK, p-Akt, p-FoxO3a and Bcl2) and down-regulated the expression of pro-apoptotic protein (Bax). Moreover, we found that Wnt signals (Wnt3a, Wnt5a, Lrp5, Lrp6 and β-catenin) played an important role in promoting osteogenic differentiation of osteoblasts under oxidative condition. Copyright © 2018 Elsevier Ltd. All rights reserved.

Members of FOX family could be drug targets of cancers.

PubMed

Wang, Jinhua; Li, Wan; Zhao, Ying; Kang, De; Fu, Weiqi; Zheng, Xiangjin; Pang, Xiaocong; Du, Guanhua

2018-01-01

FOX families play important roles in biological processes, including metabolism, development, differentiation, proliferation, apoptosis, migration, invasion and longevity. Here we are focusing on roles of FOX members in cancers, FOX members and drug resistance, FOX members and stem cells. Finally, FOX members as drug targets of cancer treatment were discussed. Future perspectives of FOXC1 research were described in the end. Copyright © 2017 Elsevier Inc. All rights reserved.

Clinical relevance of miR-mediated HLA-G regulation and the associated immune cell infiltration in renal cell carcinoma.

PubMed

Jasinski-Bergner, Simon; Stoehr, Christine; Bukur, Juergen; Massa, Chiara; Braun, Juliane; Hüttelmaier, Stefan; Spath, Verena; Wartenberg, Roland; Legal, Wolfgang; Taubert, Helge; Wach, Sven; Wullich, Bernd; Hartmann, Arndt; Seliger, Barbara

2015-06-01

In human tumors of distinct origin including renal cell carcinoma (RCC), the non-classical human leukocyte antigen G (HLA-G) is frequently expressed, thereby inhibiting the cytotoxic activity of T and natural killer (NK) cells. Recent studies demonstrated a strong post-transcriptional gene regulation of the HLA-G by miR-152, -148A, -148B and -133A. Standard methods were applied to characterize the expression and function of HLA-G, HLA-G-regulatory microRNAs (miRs) and the immune cell infiltration in 453 RCC lesions using a tissue microarray and five RCC cell lines linking these results to clinical parameters. Direct interactions with HLA-G regulatory miRs and the HLA-G 3' untranslated region (UTR) were detected and the affinities of these different miRs to the HLA-G 3'-UTR compared. qPCR analyses and immunohistochemical staining revealed an inverse expression of miR-148A and -133A with the HLA-G protein in situ and in vitro . Stable miR overexpression caused a downregulation of HLA-G protein enhancing the NK and LAK cell-mediated cytotoxicity in in vitro CD107a activation assays revealing a HLA-G-dependent cytotoxic activity of immune effector cells. A significant higher frequency of CD3 + /CD8 + T cell lymphocytes, but no differences in the activation markers CD69, CD25 or in the presence of CD56 + , FoxP3 + and CD4 + immune cells were detected in HLA-G + compared to HLA-G - RCC lesions. This could be associated with higher WHO grade, but not with a disease-specific survival. These data suggest a miR-mediated control of HLA-G expression in RCC, which is associated with a distinct pattern of immune cell infiltration.

The effects of hyperthermia on the immunomodulatory properties of human umbilical cord vein mesenchymal stem cells (MSCs).

PubMed

Hesami, Shilan; Mohammadi, Mehdi; Rezaee, Mohamad Ali; Jalili, Ali; Rahmani, Mohammad Reza

2017-11-01

Hyperthermia can modulate inflammation and the immune response. Based on the recruitment of mesenchymal stem cells (MSCs) to inflamed tissues and the immunomodulatory properties of these cells, the aim of this study was to examine the effects of hyperthermia on the immunomodulatory properties of MSCs in a mixed lymphocyte reaction (MLR). Passages 4-6 of human umbilical cord vein mesenchymal stem cells were co-cultured in a two-way MLR. Cells in the hyperthermia groups were incubated at 41 °C for 45 min. A colorimetric assay was employed to examine the effects of MSCs on cell proliferation. The levels of IL-4 and TNF-α proteins in the cell culture supernatant were measured, and non-adherent cells were used for RNA extraction, which was then used for cDNA synthesis. RT-PCR was utilised to assess levels of IL-10, IL-17A, IL-4, TNF-α, TGF-β1, FOX P 3 , IFN-γ, CXCL12 and β-actin mRNA expression. UCV-MSCs co-cultured in an MLR reduced lymphocyte proliferation at 37 °C, whereas hyperthermia attenuated this effect. Hyperthermia increased expression of IL-10, TGF-β1 and FOXP3 mRNAs in co-culture; however, no effects on IL-17A and IFN-γ were observed, and it reduced CXCL12 expression. In co-culture, IL-4 mRNA and protein increased at 37 °C, an effect that was reduced by hyperthermia. No considerable change in TNF-α mRNA expression was found in hyperthermia-treated cells. Hyperthermia increases cell proliferation of the peripheral blood mononuclear cells and modifies the cytokine profile in the presence of UCV-MSCs.

Genetic signatures of adaptation revealed from transcriptome sequencing of Arctic and red foxes.

PubMed

Kumar, Vikas; Kutschera, Verena E; Nilsson, Maria A; Janke, Axel

2015-08-07

The genus Vulpes (true foxes) comprises numerous species that inhabit a wide range of habitats and climatic conditions, including one species, the Arctic fox (Vulpes lagopus) which is adapted to the arctic region. A close relative to the Arctic fox, the red fox (Vulpes vulpes), occurs in subarctic to subtropical habitats. To study the genetic basis of their adaptations to different environments, transcriptome sequences from two Arctic foxes and one red fox individual were generated and analyzed for signatures of positive selection. In addition, the data allowed for a phylogenetic analysis and divergence time estimate between the two fox species. The de novo assembly of reads resulted in more than 160,000 contigs/transcripts per individual. Approximately 17,000 homologous genes were identified using human and the non-redundant databases. Positive selection analyses revealed several genes involved in various metabolic and molecular processes such as energy metabolism, cardiac gene regulation, apoptosis and blood coagulation to be under positive selection in foxes. Branch site tests identified four genes to be under positive selection in the Arctic fox transcriptome, two of which are fat metabolism genes. In the red fox transcriptome eight genes are under positive selection, including molecular process genes, notably genes involved in ATP metabolism. Analysis of the three transcriptomes and five Sanger re-sequenced genes in additional individuals identified a lower genetic variability within Arctic foxes compared to red foxes, which is consistent with distribution range differences and demographic responses to past climatic fluctuations. A phylogenomic analysis estimated that the Arctic and red fox lineages diverged about three million years ago. Transcriptome data are an economic way to generate genomic resources for evolutionary studies. Despite not representing an entire genome, this transcriptome analysis identified numerous genes that are relevant to arctic adaptation in foxes. Similar to polar bears, fat metabolism seems to play a central role in adaptation of Arctic foxes to the cold climate, as has been identified in the polar bear, another arctic specialist.

Spatio-temporal Analysis of the Genetic Diversity of Arctic Rabies Viruses and Their Reservoir Hosts in Greenland

PubMed Central

Hanke, Dennis; Freuling, Conrad M.; Fischer, Susanne; Hueffer, Karsten; Hundertmark, Kris; Nadin-Davis, Susan; Marston, Denise; Fooks, Anthony R.; Bøtner, Anette; Mettenleiter, Thomas C.; Beer, Martin; Rasmussen, Thomas B.; Müller, Thomas F.; Höper, Dirk

2016-01-01

There has been limited knowledge on spatio-temporal epidemiology of zoonotic arctic fox rabies among countries bordering the Arctic, in particular Greenland. Previous molecular epidemiological studies have suggested the occurrence of one particular arctic rabies virus (RABV) lineage (arctic-3), but have been limited by a low number of available samples preventing in-depth high resolution phylogenetic analysis of RABVs at that time. However, an improved knowledge of the evolution, at a molecular level, of the circulating RABVs and a better understanding of the historical perspective of the disease in Greenland is necessary for better direct control measures on the island. These issues have been addressed by investigating the spatio-temporal genetic diversity of arctic RABVs and their reservoir host, the arctic fox, in Greenland using both full and partial genome sequences. Using a unique set of 79 arctic RABV full genome sequences from Greenland, Canada, USA (Alaska) and Russia obtained between 1977 and 2014, a description of the historic context in relation to the genetic diversity of currently circulating RABV in Greenland and neighboring Canadian Northern territories has been provided. The phylogenetic analysis confirmed delineation into four major arctic RABV lineages (arctic 1–4) with viruses from Greenland exclusively grouping into the circumpolar arctic-3 lineage. High resolution analysis enabled distinction of seven geographically distinct subclades (3.I – 3.VII) with two subclades containing viruses from both Greenland and Canada. By combining analysis of full length RABV genome sequences and host derived sequences encoding mitochondrial proteins obtained simultaneously from brain tissues of 49 arctic foxes, the interaction of viruses and their hosts was explored in detail. Such an approach can serve as a blueprint for analysis of infectious disease dynamics and virus-host interdependencies. The results showed a fine-scale spatial population structure in Greenland arctic foxes based on mitochondrial sequences, but provided no evidence for independent isolated evolutionary development of RABV in different arctic fox lineages. These data are invaluable to support future initiatives for arctic fox rabies control and elimination in Greenland. PMID:27459154

Spatio-temporal Analysis of the Genetic Diversity of Arctic Rabies Viruses and Their Reservoir Hosts in Greenland.

PubMed

Hanke, Dennis; Freuling, Conrad M; Fischer, Susanne; Hueffer, Karsten; Hundertmark, Kris; Nadin-Davis, Susan; Marston, Denise; Fooks, Anthony R; Bøtner, Anette; Mettenleiter, Thomas C; Beer, Martin; Rasmussen, Thomas B; Müller, Thomas F; Höper, Dirk

2016-07-01

There has been limited knowledge on spatio-temporal epidemiology of zoonotic arctic fox rabies among countries bordering the Arctic, in particular Greenland. Previous molecular epidemiological studies have suggested the occurrence of one particular arctic rabies virus (RABV) lineage (arctic-3), but have been limited by a low number of available samples preventing in-depth high resolution phylogenetic analysis of RABVs at that time. However, an improved knowledge of the evolution, at a molecular level, of the circulating RABVs and a better understanding of the historical perspective of the disease in Greenland is necessary for better direct control measures on the island. These issues have been addressed by investigating the spatio-temporal genetic diversity of arctic RABVs and their reservoir host, the arctic fox, in Greenland using both full and partial genome sequences. Using a unique set of 79 arctic RABV full genome sequences from Greenland, Canada, USA (Alaska) and Russia obtained between 1977 and 2014, a description of the historic context in relation to the genetic diversity of currently circulating RABV in Greenland and neighboring Canadian Northern territories has been provided. The phylogenetic analysis confirmed delineation into four major arctic RABV lineages (arctic 1-4) with viruses from Greenland exclusively grouping into the circumpolar arctic-3 lineage. High resolution analysis enabled distinction of seven geographically distinct subclades (3.I - 3.VII) with two subclades containing viruses from both Greenland and Canada. By combining analysis of full length RABV genome sequences and host derived sequences encoding mitochondrial proteins obtained simultaneously from brain tissues of 49 arctic foxes, the interaction of viruses and their hosts was explored in detail. Such an approach can serve as a blueprint for analysis of infectious disease dynamics and virus-host interdependencies. The results showed a fine-scale spatial population structure in Greenland arctic foxes based on mitochondrial sequences, but provided no evidence for independent isolated evolutionary development of RABV in different arctic fox lineages. These data are invaluable to support future initiatives for arctic fox rabies control and elimination in Greenland.