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At least 649 records · Page 36

Copine1 regulates neural stem cell functions during brain development

Highlights: • Copine1 is highly expressed in neural lineage cells at early developmental stages. • Copine1 regulates the proliferation of embryonic neural stem cells (NSCs). • Copine1 regulates the differentiation of NSCs into neuronal and glial lineages. • mTOR signaling pathway is involved in Copine1-meidated neural development. Copine 1 (CPNE1) is a well-known phospholipid binding protein in plasma membrane of various cell types. In brain cells, CPNE1 is closely associated with AKT signaling pathway, which is important for neural stem cell (NSC) functions during brain development. Here, we investigated the role of CPNE1 in the regulation of brain NSC functions during brain development and determined its underlying mechanism. In this study, abundant expression of CPNE1 was observed in neural lineage cells including NSCs and immature neurons in human. With mouse brain tissues in various developmental stages, we found that CPNE1 expression was higher at early embryonic stages compared to postnatal and adult stages. To model developing brain in vitro, we used primary NSCs derived from mouse embryonic hippocampus. Our in vitro study shows decreased proliferation and multi-lineage differentiation potential in CPNE1 deficient NSCs. Finally, we found that the deficiency of CPNE1 downregulated mTOR signaling in embryonic NSCs. These data demonstrate that CPNE1 plays a key role in the regulation of NSC functions through the activation of AKT-mTOR signaling pathway during brain development.

60 APPLIED LIFE SCIENCES↗

SETDB1-mediated FosB regulation via ERK2 is associated with an increase in cell invasiveness during anticancer drug treatment of A549 human lung cancer cells

Highlights: • SETDB1 directly regulates FosB expression during doxorubicin treatment. • PD98059 restores the expression of SETDB1 and FosB by doxorubicin treatment. • SETDB1-mediated FosB regulation through ERK2 is responsible for cell survival. • Ectopic FosB expression increases transforming and migration activity. • ERK2-SETDB1-FosB pathway has an anti-therapeutic regulatory mechanism during anticancer drug treatment. We have determined a functional link to the inverse expression of SETDB1 and FosB following anticancer drug treatment. Doxorubicin treatment caused decreased SETDB1 expression and FosB overexpression both at the mRNA and protein levels. The decreased HMTase activity of SETDB1 coincided with altered occupancy across the promoter region of the FosB gene. SETDB1 overexpression decreased the luciferase reporter activity containing the FosB promoter region, but siSETDB1 increased the luciferase reporter activity, suggesting that SETDB1 directly and negatively regulated FosB expression. In addition, MEK inhibitor (PD98059) blocked the SETDB1 regulation of the FosB promoter activity via ERK2 activation during doxorubicin treatment. A microscopic analysis reveals that FosB expression was observed in living cells in spite of doxorubicin treatment. Ectopic FosB/ΔFosB expression increased the number of colonies and the migration of A549 cells compared to that in control. These results suggest that the ERK2-SETDB1-FosB signaling pathway might have an anti-therapeutic regulatory mechanism that increases the transformation and migration activity of cancer cells during anticancer drug treatment.

60 APPLIED LIFE SCIENCES↗

miR-3065-5p regulates mouse odontoblastic differentiation partially through bone morphogenetic protein receptor type II

Highlights: • miR-3065-5p is significantly up-regulated during odontoblastic differentiation. • miR-3065-5p directly targets Bmpr2 and indirectly targets Adamts2. • Bmpr2 exerts different roles in the different stages of odontoblastic differentiation. Illumination of the molecular mechanisms regulating odontoblastic differentiation of dental papilla cells is of great significance for proper dentinogenesis and dental pulp regeneration. In this study, we discovered that microRNA (miR)-3065-5p is up-regulated during odontoblastic differentiation. Overexpression of miR-3065-5p promoted odontoblastic differentiation in vitro. Dual luciferase report assay verified that miR-3065-5p could bind to the 3′UTR of bone morphogenetic protein receptor type II (BMPR2), which dramatically increased in the beginning of odontoblastic differentiation but decreased in the terminal differentiation stage. Inhibition of Bmpr2 in the early stage retarded odontoblastic differentiation while knockdown of Bmpr2 in the terminal stage enhanced odontoblastic differentiation, resembling the effect of miR-3065-5p. Taken together, our present study suggests that miR-3065-5p positively regulates odontoblastic differentiation by directly binding to Bmpr2 in the terminal differentiation stage.

60 APPLIED LIFE SCIENCES↗

Epigenetic regulation of hibernation-associated HP-20 and HP-27 gene transcription in chipmunk liver

Highlights: • HP-20 and HP-27 gene transcription is regulated according to chipmunk hibernation. • In parallel, changes occur in the histone modifications on these gene promoters. • Coactivators are recruited to these promoters in nonhibernating chipmunks. • HNF-1 plays a key role in the epigenetic regulation of the HP-20 and HP-27 genes. The chipmunk hibernation-related proteins (HPs) HP-20 and HP-27 are components of a 140-kDa complex that dramatically decreases in the blood during hibernation. The HP-20 and HP-27 genes are expressed specifically in the liver and are downregulated in hibernating chipmunks. Hibernation-associated physiological changes are assumed to be under genetic control. Therefore, to elucidate the molecular mechanisms of hibernation, here we examined the mechanisms behind the altered HP-20 and HP-27 gene expression in nonhibernating versus hibernating chipmunks. Chromatin immunoprecipitation (ChIP) analyses revealed that histone H3 on the HP-20 and HP-27 gene promoters was highly acetylated at lysine (K) 9 and K14 and highly trimethylated at K4 in the liver of nonhibernating chipmunks, while these active histone modifications were nearly absent in hibernating chipmunks. Furthermore, histone acetyltransferases and a histone methyltransferase were associated with the HP-20 and HP-27 gene promoters primarily in nonhibernating chipmunks. Consistent with a previous finding that HNF-1 and USF can activate HP-20 and HP-27 gene transcription by binding to the proximal promoter region, ChIP-quantitative PCR (qPCR) analyses revealed that significantly less HNF-1 and USF were bound to these gene promoters in hibernating than in nonhibernating chipmunks. These findings collectively indicated that the hibernation-associated HP-20 and HP-27 gene expression is epigenetically regulated at the transcriptional level by the binding of HNF-1 and USF to their proximal promoters, and that histone modification has a key role in hibernation-associated transcriptional regulation.

60 APPLIED LIFE SCIENCES↗

PKC and Rab13 mediate Ca2+ signal-regulated GLUT4 traffic

Highlights: • Ionomycin increases cell surface GLUT4 levels by inhibiting GLUT4 endocytosis and promoting GLUT4 exocytosis. • PKCα and PKCθ are involved in ionomycin-regulated GLUT4 endocytosis. • PKCθ regulates GLUT4 exocytosis in response to ionomycin. • Rab13 is required for ionomycin-promoted GLUT4 exocytosis. Exercise/muscle contraction increases cell surface glucose transporter 4 (GLUT4), leading to glucose uptake to regulate blood glucose level. Elevating cytosolic Ca{sup 2+} mediates this effect, but the detailed mechanism is not clear yet. We used calcium ionophore ionomycin to raise intracellular cytosolic Ca{sup 2+} level to explore the underlying mechanism. We showed that in L6 myoblast muscle cells stably expressing GLUT4myc, ionomycin increased cell surface GLUT4myc levels and the phosphorylation of AS160, TBC1D1. siPKCα and siPKCθ but not siPKCδ and siPKCε inhibited the ionomycin-increased cell surface GLUT4myc level. siPKCα, siPKCθ inhibited the phosphorylation of AS160 and TBC1D1 induced by ionomycin. siPKCα and siPKCθ prevented ionomycin-inhibited endocytosis of GLUT4myc. siPKCθ, but not siPKCα inhibited ionomycin-stimulated exocytosis of GLUT4myc. siRab13 but not siRab8a, siRab10 and siRab14 inhibited the exocytosis of GLUT4myc promoted by ionomycin. In summary, ionomycin-promoted exocytosis of GLUT4 is partly reversed by siPKCθ, whereas ionomycin-inhibited endocytosis of GLUT4 requires both siPKCα and siPKCθ. PKCα and PKCθ contribute to ionomycin-induced phosphorylation of AS160 and TBC1D1. Rab13 is required for ionomycin-regulated GLUT4 exocytosis.

60 APPLIED LIFE SCIENCES↗

Long non-coding RNA PVT1-5 promotes cell proliferation by regulating miR-126/SLC7A5 axis in lung cancer

Highlights: • LncRNA-PVT1-5 is up-regulated in lung cancer tissues and cell lines. • LncRNA-PVT1-5 acted as a sponge for miR-126 to regulate cells proliferation in lung cancer cells. • LncRNA-PVT1-5 exerts its role via miR-126/SLC7A5 axis in lung cancer cell modes. Dysregulated long non-coding RNAs (lncRNAs) and microRNAs (miRNAs) play key roles in the development of human cancers. The lncRNA plasmacytoma variant translocation 1 (PVT1) is reported to be an oncogene in a variety of cancers. However, the roles of PVT1-5 and its related miRNAs in lung cancer are poorly understood. In this study, we found that PVT1-5 expression was significantly increased in lung cancer tissues and cell lines. By using biotin-labeled lncRNA-PVT1-5 probe for miRNA in vivo precipitation (miRIP) in lung cancer cells and dual-luciferase reporterassays, we identified that miR-126 was associated with lncRNA-PVT1-5. Furthermore, knockdown of lncRNA-PVT1-5 in cells could down-regulate the expression of SLC7A5, the target of oncogenic miR-126, resulting in the cell proliferation. Conversely, inhibiting the expression of miR-126 markedly increased the expression of SLC7A5 and alleviated cell proliferation inhibition. Thus, our results indicated that lncRNA-PVT1-5 may function as a competing endogenous RNA (ceRNA) for miR-126 to promote cell proliferation by regulating the miR-126/SLC7A5 pathway, suggesting that lncRNA-PVT1-5 plays a crucial role in lung cancer progression and lncRNA-PVT1-5/miR-126/SLC7A5 regulatory network may shed light on tumorigenesis in lung cancer.

60 APPLIED LIFE SCIENCES↗

Characterization of the promoter region of bovine SIX4: Roles of E-box and MyoD in the regulation of basal transcription

Highlights: • Bovine SIX4 was highly expressed in the longissimus thoracis and in undifferentiated Qinchuan cattle muscle cells. • The core promoter of bovine SIX4 was located within the region −522/-193 relative to the TSS. • MyoD binding occurs in the core promoter of bovine SIX4 through MyoD and Ebox recognition sites and plays an important role in the transcriptional regulation of the bovine SIX4. The sine oculis homeobox 4 (SIX4) gene belongs to the Six gene family and encodes an evolutionarily conserved transcription factor. Previous studies have demonstrated that SIX4 plays an essential role in proper muscle regeneration. However, the mechanisms regulating SIX4 transcription remain elusive. In the present study, we determined that bovine SIX4 was highly expressed in the longissimus thoracis and in undifferentiated Qinchuan cattle muscle cells (QCMCs) and that its protein localizes to both the cytoplasm and the nucleus. To elucidate the bovine the molecular mechanisms of SIX4 regulation, 1.3 kb of the 5′-regulatory region was obtained. MyoD and Ebox recognition sites were identified in the core promoter region at −522/-193 of the bovine SIX4 using a series of 5′ deletion promoter plasmids in luciferase reporter assays. An electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation (ChIP) assay in combination with site-directed mutation and siRNA interference demonstrated that MyoD binding occurs at MyoD and Ebox recognition sites through direct and indirect mechanisms and play important roles in the transcriptional regulation of the bovine SIX4 promoter. Taken together, these interactions provide insight into the regulatory mechanisms of SIX4 transcription in mediating skeletal muscle growth in cattle.

60 APPLIED LIFE SCIENCES↗

LncRNA MALAT1 is up-regulated in diabetic gastroparesis and involved in high-glucose-induced cellular processes in human gastric smooth muscle cells

Highlights: • MALAT1 was dysregulated in rat model of DGP and the samples from patients from diabetic patients with DGP symptoms. • MALAT1 played key role in the cellular processes in human gastric SMCs. • MALAT1 involved in the function of high-glucose treatments in human gastric SMCs. Recent years, widespread long non-coding RNAs (lncRNAs) were identified and known as regulator of gene expression. Diabetic gastroparesis (DGP) is one of the most common chronic complications of diabetes mellitus. There was no research reported the role of lncRNAs in DGP. In this study, we firstly established a rat model of DGP by STZ injection. Then, we detected the expression of MALAT1 and found that expression of MALAT1 was up-regulated in rat model of DGP, comparing to the control group (P < .01). Furthermore, we revealed that MALAT1 expression was increased in the samples from diabetic patients with DGP symptoms, in comparison with the control. In addition, we demonstrated that the inhibition of MALAT1 increased the expression of α-SMA and SM myosin heavy chains, reduced the cell viability, inhibited the potential of cell migration and induced cell apoptosis in human gastric smooth muscle cells (SMCs). Ultimately, we found that the regulation of MALAT1 expression modulated the function of high-glucose stimulation in human gastric SMCs. Therefore, our study firstly indicated that MALAT1 was up-regulated in DGP and played an important role in the pathogenesis of DGP.

60 APPLIED LIFE SCIENCES↗

The suppressive effect of puerarin on atopic dermatitis-like skin lesions through regulation of inflammatory mediators in vitro and in vivo

Highlights: • Puerarin regulates inflammatory cytokine, such as IL-6, IL-5, and TNF-α in human keratinocyte cell line. • Puerarin attenuates inflammation related protein expression level in human keratinocyte cell line. • Puerarin improves DNCB-induced atopic skin condition by regulating of clinical signs and skin tissue injury. • Oral administration of puerarin recovers inflammatory cytokine secretion in DNCB-induced atopic dermatitis. Atopic dermatitis (AD) is one of the common inflammatory immune disorders. Puerarin is the main isoflavonoid obtained from the root of Pueraria lobata and has been known have ameliorative effects on diverse inflammatory diseases. However, the effects of puerarin on AD have not been uncovered. 2,4-dinitrochlorobenzene (DNCB) was used to induce atopic dermatitis(AD)-like skin lesions on BALB/c mice for 17 days. Further, the BALB/c mice were orally administered puerarin. Puerarin ameliorated DNCB-induced AD-like symptoms in the mice by regulating skin thickness, degranulation of mast cells, and serum immunoglobulin E (IgE). Human keratinocytes (HaCaT cells) were also used to clarify the effects of puerarin on the secretion of pro-inflammatory cytokines. Puerarin inhibited the secretion of inflammatory cytokines and chemokines. The aim of this study was to investigate the protective and alleviative effect of puerarin on AD in vitro and in vivo. The results in this study indicated that puerarin ameliorates AD-like skin lesion and skin inflammation via regulation of various atopic and inflammatory mediators. Therefore, puerarin might be useful in treating AD and other skin diseases.

60 APPLIED LIFE SCIENCES↗

Kruppel-like factor 4 regulates keratinocyte senescence

Highlights: • KLF4 is down-regulated in keratinocytes senescence and physiological skin aging. • Down-regulation of KLF4 triggers keratinocytes senescence. • KLF4 mRNA is a direct miR-34a target. • Ectopic expression of miR-34a induces keratinocytes senescence. Keratinocyte replicative senescence has an important role in time-related changes of epidermis. Previous studies demonstrated that miRNAs play key roles in inhibiting proliferation and in the acquisition of the keratinocyte senescent phenotype as well as in individual ageing. Kruppel-like factor 4 is a transcription factor with dual functions in keratinocytes, being a stemness factor and a pro-differentiation factor. Interestingly, in skin squamous cell carcinomas KLF4 expression is strongly down-regulated or absent. While KLF4 involvement in senescence and ageing has not been investigated yet. Here, we show that Klf4 protein decreases during keratinocyte replicative senescence and during physiological skin aging, while its mRNA level does not change. We demonstrated that the senescence-associated miR-34a regulates post-transcriptionally Klf4 expression. KLF4 silencing is sufficient to induce a senescent phenotype in primary keratinocytes and ectopic miR-34a over-expression phenocopies this result. Our findings identify a novel regulatory loop between miR-34a and KLF4 during keratinocytes replicative senescence. This regulatory loop, beside aging, may play a role in age-related pathologies.

60 APPLIED LIFE SCIENCES↗

Krüppel-like factor 9 suppressed tumorigenicity of the pancreatic ductal adenocarcinoma by negatively regulating frizzled-5

Highlights: • Krüppel-like factor 9 inhibited the growth of pancreatic cancer cells in vitro. • Krüppel-like factor 9 regulated the Wnt pathway through Frizzled- 5. • Krüppel-like factor 9 regulated Frizzled- 5 through binding to its promoter region. Krüppel-like factor 9 (KLF9) has been implicated in mediating a diverse range of biological processes. However, the expression pattern and biological functions of KLF9 in pancreatic ductal adenocarcinoma (PDAC) are still unknown. Here, we evaluated the role of KLF9 in pancreatic ductal adenocarcinoma (PDAC). Overexpression of KLF9 significantly inhibited proliferation and clone formation in PDAC cells, while silencing KLF9 expression dramatically promoted this effect in vitro. Knocking down the expression of KLF9 also promoted the tumorigenesis in the PDAC mouse xneograft model. In in vitro mechanism study, KLF9 negatively regulated the activity of wnt/beta-catenin pathway in Top/Fop reporter assay. Frizzled-5, a key component involving in this pathway, was sharp inhibited by KLF9 both in mRNA and protein level. Furthermore, a KLF9-binding site (BTE) was identified in the promoter region of Frizzled-5. Mutation or deletion of this BTE strongly disrupted the KLF9's regulatory effect on Frizzled-5. More importantly, the expression level of KLF9 was significantly lower in clinical PDAC tissue compared to matched normal tissues and inversely associated with survival of the patients. Together, our findings indicated that KLF9 suppressed tumorigenicity of the pancreatic ductal adenocarcinoma by negatively regulating frizzled-5.

60 APPLIED LIFE SCIENCES↗

CBX3 promotes proliferation and regulates glycolysis via suppressing FBP1 in pancreatic cancer

More and more evidence has demonstrated that Chromobox protein homolog 3(CBX3) has an important role in carcinogenesis by regulating several mechanisms, such as heterochromatin formation, gene silencing, DNA replication and repair. However, its role in pancreatic cancer has seldom been discussed. In the present study, we silenced CBX3 expression in pancreatic cancer cell lines and identified the positive roles of CBX3 in cancer cell proliferation. Furthermore, we demonstrated that silencing CBX3 in pancreatic cancer cells inhibited aerobic glycolysis, the basis for providing cancer cells with building blocks for macromolecule synthesis and ATP that required. To search for the underlying molecular mechanism, we turned to examine the impact of CBX3 on the expression of FBP1, a negative regulator of aerobic glycolysis in pancreatic cancer and indicated that CBX3 negatively regulated FBP1 expression. Silencing FBP1 expression attenuated the decrease in glycolytic capacity that caused by CBX3 knockdown in pancreatic cancer cells. Taken together, these data reveal that CBX3 serves as a positive regulator of aerobic glycolysis via suppressing of the FBP1 in pancreatic cancer cells. Disrupting the CBX3-FBP1 signaling axis would be effective to treat pancreatic cancer and prevent aerobic glycolysis.

60 APPLIED LIFE SCIENCES↗

Nrf2 activation protects against intratracheal LPS induced mouse/murine acute respiratory distress syndrome by regulating macrophage polarization

The transcription factor nuclear factor E2-related factor 2 (Nrf2) is known to control the expression of antioxidant response elements and cytoprotective genes and modulate inflammatory response, helping to ameliorate damage in many diseases. Exactly how Nrf2 regulates innate inflammatory homeostasis remains unclear. In this study, we provide in vitro and in vivo evidence that Nrf2 plays a crucial role in macrophage polarization and acute respiratory distress syndrome (ARDS). We conducted in vitro experiments using a mouse alveolar macrophage cell line as well as primary cultures of macrophages in which cells were exposed to lipopolysaccharide (LPS) or interferon-γ in order to mimic ARDS, in the presence or absence of the Nrf2 activator tert-butylhydroquinone (tBHQ). Using siRNA-mediated Nrf2 knockdown, we showed that Nrf2 inhibited the inflammatory response by promoting M2 macrophage polarization and inhibiting M1 macrophage polarization. At the same time, tBHQ activated Nrf2-mediated inhibition of the p65 nuclear factor-κB pathway and activation of peroxisome proliferator-activated receptor-γ, which play important roles in regulating macrophage polarization. We also conducted in vivo experiments in which mice were given tBHQ with or without intratracheal LPS, then their survival was monitored, lung injury was assessed using histology, and levels of pro- and anti-inflammatory cytokines were assayed in the lungs and serum. Activation of Nrf2 with tBHQ dramatically reduced LPS-induced mortality and lung injury, down-regulated pro-inflammatory mediators and up-regulated anti-inflammatory mediators. These results suggest that Nrf2 can help prevent ARDS progression by promoting M2 polarization of macrophages. Interfering with Nrf2 may be an effective strategy for reprogramming macrophage polarization in order to treat ARDS.

60 APPLIED LIFE SCIENCES↗

Lenalidomide regulates osteocytes fate and related osteoclastogenesis via IL-1β/NF-κB/RANKL signaling

Highlights: • Lenalidomide regulated IL-1β induced osteocyte fate with decreased expressions of RANKL and Sclerostin. • Lenalidomide inhibited subsequent osteoclastogenesis via osteocytes. • Lenalidomide inactivated NF-κB signaling in osteocytes to reduce osteoclast formation. • Lenalidomide attenuated in vivo osteocyte apoptosis and following osteoclastogenesis in osteoarthritis mice. Osteolytic diseases are closely associated with osteocyte fate, indicating a more efficient and crucial role of osteocyte-targeting strategy in inhibiting osteoclastogenesis. Here, we investigated the effects of lenalidomide (Lena) on osteocyte fate in order to regulate osteoclastogenesis via effective cascade-controlling response. Our data revealed that lenalidomide treatment notably rescued IL-1β induced loss of osteocyte viability by inhibiting osteocyte apoptosis with decreased osteoclast-related factors, RANKL and Sclerostin, as demonstrated by the restricted osteoclast formation and reduced bone resorption. Additionally, iTRAQ assay revealed that IL-1β induced activation of NF-κB inhibitor α/β were remarkably downregulated by lenalidomide, showing that lenalidomide impaired NF-κB signaling in osteocytes for inhibiting the expression of osteoclast specific genes in osteoclasts, which was further confirmed by KEGG pathway analysis and Western blot. More interestingly, the in vivo analysis of osteocyte apoptosis and osteoclastogenesis in osteoarthritis mice model indicated a role of lenalidomide in the regulation of osteocyte fate and the consequent inhibition of RANKL-induced osteoclastogenesis. Together, these results suggest that lenalidomide regulates osteocyte fate by attenuating IL-1β/NF-κB signaling, thereby inhibiting RANKL expression for the attenuated osteoclastogenesis both in vitro and vivo, indicating a more efficient remedy among future anti-osteoclastogenesis approaches.

60 APPLIED LIFE SCIENCES↗

ATP6V1H regulates the growth and differentiation of bone marrow stromal cells

Highlights: • Lack of ATP6V1H inhibits the proliferation of bone marrow stromal cells (BMSCs). • Partial loss of ATP6V1H inhibits osteogenic differentiation and promotes adipogenic differentiation of BMSCs. • ATP6V1H interacts with TGF-β receptor I and AP-2 complex to regulate the proliferation and differentiation of BMSCs. ATP6V1H encodes subunit H of vacuolar ATPase (V-ATPase) and may regulate osteoclastic function. The deficiency of ATP6V1H caused bone loss in human, mouse and zebrafish. In this report, we identified the mechanisms by which ATP6V1H regulates proliferation and differentiation of bone marrow stromal cells (BMSCs). We found that ATP6V1H was expressed in BMSCs, and Atp6v1h{sup +/-} BMSCs exhibited the lower proliferation rate, cell cycle arrest and reduced osteogenic differentiation capacity, as well as the increased adipogenic potentials. Histologic analysis confirmed less bone formation and more fatty degeneration in Atp6v1h{sup +/-} mice in the different age groups. Q-PCR analysis revealed that loss of ATP6V1H function downregulated the mRNA level of TGF-β1 receptor, and its binding molecule, subunit β of adaptor protein complex 2 (AP-2), suggesting ATP6V1H regulates the proliferation and differentiation of BMSCs by interacting with TGF-β receptor I and AP-2 complex.

60 APPLIED LIFE SCIENCES↗

USP10 regulates the stability of the EMT-transcription factor Slug/SNAI2

Highlights: • By undertaking a genome-wide siRNA screen, we have identified USP10 as regulator of Slug stability. • We show that USP10 binds Slug and mediates its degradation by the proteasome. • We provide detailed evidences that genetic depletion of USP10 causes beyond, a reduction of Slug, also suppress Vimetin levels (a hallmark mesenchymal marker) and migration. • Reversely, expression of USP10 stabilizes and elevates Slug. • Importantly, we show that USP10 expression correlates with Slug expression in primary tumor biopsies. Epithelial-to-mesenchymal transition (EMT) is a fundamental mechanism governing the switch of cells from an epithelial to a motile mesenchymal-like state. This transdifferentiation is regulated by key transcription factors, including Slug. The stability and function of Slug can be regulated by multiple mechanisms, including ubiquitin-mediated post-translational modifications. Here, by using a genome wide siRNA screen for human deubiquitinating enzymes (DUBs), we identified USP10 as a deubiquitinase for Slug in cancer cells. USP10 interacts with Slug and mediates its degradation by the proteasome. Importantly, USP10 is concomitantly highly expressed with Slug in cancer biopsies. Genetic knockdown of USP10 leads to suppressed Slug levels with a decreased expression of the mesenchymal marker Vimentin. Further, it reduces the migratory capacity of cancer cells. Reversely, overexpression of USP10 elevates the level of both Slug and Vimentin. Our study identifies USP10 as a regulator of the EMT-transcription factor Slug and cell migration.

60 APPLIED LIFE SCIENCES↗

HDAC6 regulates thermogenesis of brown adipocytes through activating PKA to induce UCP1 expression

Highlights: • HDAC6 regulates thermogenesis of brown adipose tissue. • cAMP-PKA signaling is responsible for HDAC6-dependent thermogenic regulation to control UCP1 expression. • HDAC6-dependent regulation of UCP1 affects lipid metabolism in brown adipose tissue. Mitochondrial uncoupling protein 1 (UCP1) is responsible for nonshivering thermogenesis in brown adipose tissue (BAT). UCP1 increases the conductance of the inner mitochondrial membrane (IMM) for protons to make BAT mitochondria generate heat rather than ATP. HDAC6 is a cytosolic deacetylase for non-histone substrates to regulate various cellular processes, including mitochondrial quality control and dynamics. Here, we showed that the body temperature of HDAC6 knockout mice is slightly decreased in normal hosing condition. Interestingly, UCP1 was downregulated in BAT of HDAC6 knockout mice, which extensively linked mitochondrial thermogenesis. Mechanistically, we showed that cAMP-PKA signaling plays a key role in HDAC6-dependent UCP1 expression. Notably, the size of brown adipocytes and lipid droplets in HDAC6 knockout BAT is increased. Taken together, our findings suggested that HDAC6 contributes to mitochondrial thermogenesis in BAT by increasing UCP1 expression through cAMP-PKA signaling pathway.

60 APPLIED LIFE SCIENCES↗

Recombinant human brain natriuretic peptide regulates PI3K/AKT/mTOR pathway through lncRNA EGOT to attenuate hypoxia-induced injury in H9c2 cardiomyocytes

Highlights: • rhBNP alleviated hypoxia-induced H9c2 cell injury and elevated EGOT expression. • EGOT suppression reversed the effects of rhBNP on hypoxia-induced cell injury. • EGOT positively regulated the expression of Cyclin D1. • rhBNP alleviated hypoxia-induced cell injury by PI3K/AKT/mTOR pathway. This study aimed to investigate whether recombinant human brain natriuretic peptide (rhBNP) regulated hypoxia-induced injury in H9c2 cardiomyocytes through lncRNA EGOT. H9c2 cardiomyocytes were cultured under normoxia and hypoxia (21% and 3% O{sub 2}) conditions, and whether hypoxia induced injury by assessing cell viability, apoptosis and autophagy. H9c2 cells were then treated with different doses of exogenous rhBNP (200, 600 and 900 nmol/L, respectively) and the effects of rhBNP on hypoxia-induced injury in H9c2 cells as well as the expression of EGOT were studied. In addition, the regulatory relationships between rhBNP and EGOT as well as between rhBNP and PI3K/AKT/mTOR pathway in hypoxia-treated H9c2 cells were investigated. Hypoxia significantly induced injury in H9c2 cells (inhibited cell viability and promoted cell apoptosis and autophagy) and decreased the expression of EGOT. However, administration of rhBNP alleviated hypoxia-induced injury in H9c2 cells and elevated expression of EGOT. Suppression of EGOT significantly reversed the effects of rhBNP on hypoxia-induced injury in H9c2 cells. Further studies showed that the effects of EGOT on cell viability and apoptosis were by positively regulating the expression of Cyclin D1. Moreover, rhBNP alleviated hypoxia-induced cell injury by activating PI3K/AKT/mTOR pathway in H9c2 cells. Our results reveal that rhBNP may play a protective role in attenuating hypoxia-induced injury in H9c2 cardiomyocytes via regulating lncRNA EGOT/Cyclin D1/PI3K/AKT/mTOR pathway axis. The findings will provide a new strategy for the treatment of heart failure induced by hypoxia.

60 APPLIED LIFE SCIENCES↗