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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 1,801 records · Page 100
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DOE OSTI2015

1,25-(OH){sub 2}-vitamin D{sub 3} prevents activation of hepatic stellate cells in vitro and ameliorates inflammatory liver damage but not fibrosis in the Abcb4{sup −/−} model

Background/Purpose of the study: Vitamin D{sub 3}-deficiency is common in patients with chronic liver-disease and may promote disease progression. Vitamin D{sub 3}-administration has thus been proposed as a therapeutic approach. Vitamin D{sub 3} has immunomodulatory effects and may modulate autoimmune liver-disease such as primary sclerosing cholangitis. Although various mechanisms of action have been proposed, experimental evidence is limited. Here we test the hypothesis that active 1,25-(OH){sub 2}-vitamin D{sub 3} inhibits activation of hepatic stellate cells (HSC) in vitro and modulates liver-injury in vivo. Methods: Proliferation and activation of primary murine HSC were assessed by BrdU- and PicoGreen{sup ®}-assays, immunoblotting, immunofluorescence-microscopy, quantitative-PCR, and zymography following calcitriol-treatment. Wild-type and ATP-binding cassette transporter b4{sup −/−} (Abcb4{sup −/−})-mice received calcitriol for 4 weeks. Liver-damage, inflammation, and fibrosis were assessed by serum liver-tests, Sirius-red staining, quantitative-PCR, immunoblotting, immunohistochemistry and hydroxyproline quantification. Results: In vitro, calcitriol inhibited activation and proliferation of murine HSC as shown by reduced α-smooth muscle actin and platelet-derived growth factor-receptor-β-protein-levels, BrdU and PicoGreen®-assays. Furthermore, mRNA-levels and activity of matrix metalloproteinase 13 were profoundly increased. In vivo, calcitriol ameliorated inflammatory liver-injury reflected by reduced levels of alanine aminotransferase in Abcb4{sup −/−}-mice. In accordance, their livers had lower mRNA-levels of F4/80, tumor necrosis factor-receptor 1 and a lower count of portal CD11b positive cells. In contrast, no effect on overall fibrosis was observed. Conclusion: Calcitriol inhibits activation and proliferation of HSCs in vitro. In Abcb4{sup −/−}-mice, administration of calcitriol ameliorates inflammatory liver-damage but has no effect on biliary fibrosis after 4 weeks of treatment. - Highlights: • Calcitriol inhibits activation and proliferation of murine HSC. • Calcitriol exerts antifibrotic properties by up-regulation of MMP 13 in HSC. • Calcitriol-treatment diminished hepatic inflammatory injury in Abcb4{sup −/−}-mice. • Calcitriol-treatment does not exert antifbrotic effects in Abcb4{sup −/−}-mice. • This study highlights potential hepatoprotective effects of calcitriol in PSC.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2015

Co-purification of arrestin like proteins with alpha-enolase from bovine myocardial tissues and the possible role in heart diseases as an autoantigen

Aim: Previously, we reported that visual arrestin co-purified with glycolytic enzymes. The aim of this study was to analyze the co-purification of arrestin like proteins (ALP) in bovine cardiac tissues with enolases. Methods: The soluble extract of bovine myocardial tissues from different regions such as left and right atriums and ventricles of the bovine heart (n = 3) was analyzed by ACA-34 gel filtration, immuno-affinity column, SDS-PAGE, ELISA, western blot and a sandwich immune assay for quantification of ALP and sequence analysis. Results: We observed that; 1) The cardiac muscle contained a 50 kDa ALP at a concentration of 751 pg/mg of soluble protein extract, 2) ALP purified, by immunoaffinity, contained alpha-enolase of 48 kDa confirmed by protein sequence analysis; 3) Cardiomyocyte cells exposed to anti arrestin and anti enolase monoclonal antibodies showed decreased proliferation in vitro, 4) High level of autoantibodies were detected by ELISA (3.57% for arrestin and 9.12% for α-enolase) in serum of patients with infarcted heart disease. Conclusion: We suggest a possible interaction between ALP and alpha-enolases yielding a complex that may be involved in the induction of cardiac autoimmune diseases. - Highlights: • We examine a possible interaction between arrestin like protein and alpha-enolases in cardiomyocyte. • We demonstrated the effect of antibodies against arrestin and enolase on cardiomyocyte cell proliferation. • We suggest that this proteins complex may be involved in the induction of cardiac autoimmune diseases.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2015

Prevention of EBV lymphoma development by oncolytic myxoma virus in a murine xenograft model of post-transplant lymphoproliferative disease

Epstein–Barr virus (EBV) has been associated with a variety of epithelial and hematologic malignancies, including B-, T- and NK cell-lymphomas, Hodgkin's disease (HD), post-transplant lymphoproliferative diseases (LPDs), nasopharyngeal and gastric carcinomas, smooth muscle tumors, and HIV-associated lymphomas. Currently, treatment options for EBV-associated malignancies are limited. We have previously shown that myxoma virus specifically targets various human solid tumors and leukemia cells in a variety of animal models, while sparing normal human or murine tissues. Since transplant recipients of bone marrow or solid organs often develop EBV-associated post-transplant LPDs and lymphoma, myxoma virus may be of utility to prevent EBV-associated malignancies in immunocompromised transplant patients where treatment options are frequently limited. In this report, we demonstrate the safety and efficacy of myxoma virus purging as a prophylactic strategy for preventing post-transplant EBV-transformed human lymphomas, using a highly immunosuppressed mouse xenotransplantation model. This provides support for developing myxoma virus as a potential oncolytic therapy for preventing EBV-associated LPDs following transplantation of bone marrow or solid organ allografts. - Highlights: • Myxoma virus effectively infects and purges EBV lymphoma cells in vivo. • Oncolytic myxoma virus effectively eradicates oncogenic EBV tumorigenesis. • Ex vivo pre-treatment of myxoma virus can be effective as a preventive treatment modality for post-transplant lymphoproliferative diseases.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2015

Dehydroepiandrosterone activates AMP kinase and regulates GLUT4 and PGC-1α expression in C2C12 myotubes

Exercise and caloric restriction (CR) have been reported to have anti-ageing, anti-obesity, and health-promoting effects. Both interventions increase the level of dehydroepiandrosterone (DHEA) in muscle and blood, suggesting that DHEA might partially mediate these effects. In addition, it is thought that either 5′-adenosine monophosphate-activated protein kinase (AMPK) or peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) mediates the beneficial effects of exercise and CR. However, the effects of DHEA on AMPK activity and PGC-1α expression remain unclear. Therefore, we explored whether DHEA in myotubes acts as an activator of AMPK and increases PGC-1α. DHEA exposure increased glucose uptake but not the phosphorylation levels of Akt and PKCζ/λ in C2C12 myotubes. In contrast, the phosphorylation levels of AMPK were elevated by DHEA exposure. Finally, we found that DHEA induced the expression of the genes PGC-1α and GLUT4. Our current results might reveal a previously unrecognized physiological role of DHEA; the activation of AMPK and the induction of PGC-1α by DHEA might mediate its anti-obesity and health-promoting effects in living organisms. - Highlights: • We assessed whether dehydroepiandrosterone (DHEA) activates AMPK and PGC-1α. • DHEA exposure increased glucose uptake in C2C12 myotubes. • The phosphorylation levels of AMPK were elevated by DHEA exposure. • DHEA induced the expression of the genes PGC-1α and GLUT4. • AMPK might mediate the anti-obesity and health-promoting effects of DHEA.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2015

LXA{sub 4} actions direct fibroblast function and wound closure

Timely resolution of inflammation is crucial for normal wound healing. Resolution of inflammation is an active biological process regulated by specialized lipid mediators including the lipoxins and resolvins. Failure of resolution activity has a major negative impact on wound healing in chronic inflammatory diseases that is manifest as excess fibrosis and scarring. Lipoxins, including Lipoxin A{sub 4} (LXA{sub 4}), have known anti-fibrotic and anti-scarring properties. The goal of this study was to elucidate the impact of LXA{sub 4} on fibroblast function. Mouse fibroblasts (3T3 Mus musculus Swiss) were cultured for 72 h in the presence of TGF-β1, to induce fibroblast activation. The impact of exogenous TGF-β1 (1 ng/mL) on LXA{sub 4} receptor expression (ALX/FPR2) was determined by flow cytometry. Fibroblast proliferation was measured by bromodeoxyuridine (BrdU) labeling and migration in a “scratch” assay wound model. Expression of α-smooth muscle actin (α-SMA), and collagen types I and III were measured by Western blot. We observed that TGF-β1 up-regulates LXA{sub 4} receptor expression, enhances fibroblast proliferation, migration and scratch wound closure. α-SMA levels and Collagen type I and III deposition were also enhanced. LXA{sub 4} slowed fibroblast migration and scratch wound closure at early time points (24 h), but wound closure was equal to TGF-β1 alone at 48 and 72 h. LXA{sub 4} tended to slow fibroblast proliferation at both concentrations, but had no impact on α-SMA or collagen production by TGF-β1 stimulated fibroblasts. The generalizability of the actions of resolution molecules was examined in experiments repeated with resolvin D2 (RvD2) as the agonist. The activity of RvD2 mimicked the actions of LXA{sub 4} in all assays, through an as yet unidentified receptor. The results suggest that mediators of resolution of inflammation enhance wound healing and limit fibrosis in part by modulating fibroblast function. - Highlights: • TGF-β1 up-regulates LXA{sub 4} receptor (ALX/FPR2) expression on fibroblast. • LXA{sub 4} regulates fibroblast migration and proliferation induced by TGF-β1. • SPMs have no impact on α-SMA, collagen type-I and III expression by fibroblast. • RvD2 regulates TGF-β1-induced fibroblast proliferation and scratch wound closure.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2015

A potential link between insulin signaling and GLUT4 translocation: Association of Rab10-GTP with the exocyst subunit Exoc6/6b

Insulin increases glucose transport in fat and muscle cells by stimulating the exocytosis of specialized vesicles containing the glucose transporter GLUT4. This process, which is referred to as GLUT4 translocation, increases the amount of GLUT4 at the cell surface. Previous studies have provided evidence that insulin signaling increases the amount of Rab10-GTP in the GLUT4 vesicles and that GLUT4 translocation requires the exocyst, a complex that functions in the tethering of vesicles to the plasma membrane, leading to exocytosis. In the present study we show that Rab10 in its GTP form binds to Exoc6 and Exoc6b, which are the two highly homologous isotypes of an exocyst subunit, that both isotypes are found in 3T3-L1 adipocytes, and that knockdown of Exoc6, Exoc6b, or both inhibits GLUT4 translocation in 3T3-L1 adipocytes. These results suggest that the association of Rab10-GTP with Exoc6/6b is a molecular link between insulin signaling and the exocytic machinery in GLUT4 translocation. - Highlights: • Insulin stimulates the fusion of vesicles containing GLUT4 with the plasma membrane. • This requires vesicular Rab10-GTP and the exocyst plasma membrane tethering complex. • We find that Rab10-GTP associates with the Exoc6 subunit of the exocyst. • We find that knockdown of Exoc6 inhibits fusion of GLUT4 vesicles with the membrane. • The interaction of Rab10-GTP with Exoc6 potentially links signaling to exocytosis.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2015

Differential expression of estrogen receptor α and β isoforms in multiple and solitary leiomyomas

Uterine leiomyomas are benign myometrial neoplasms that function as one of the common indications for hysterectomy. Clinical and biological evidences indicate that uterine leiomyomas are estrogen-dependent. Estrogen stimulates cell proliferation through binding to the estrogen receptor (ER), of which both subtypes α and β are present in leiomyomas. Clinically, leiomyomas may be singular or multiple, where the first one is rarely recurring if removed and the latter associated to a relatively young age or genetic predisposition. These markedly different clinical phenotypes indicate that there may different mechanism causing a similar smooth muscle response. To investigate the relative expression of ERα and ERβ in multiple and solitary uterine leiomyomas, we collected samples from 35 Chinese women (multiple leiomyomas n = 20, solitary leiomyoma n = 15) undergoing surgery to remove uterine leiomyomas. ELISA assay was performed to detect estrogen(E{sub 2}) concentration. Quantitative real-time PCR analysis was performed to detect ERα and ERβ mRNA expression. Western blot and immunohistochemical analysis were performed to detect ERα and ERβ protein expression. We found that ERα mRNA and protein levels of in multiple leiomyomas were significantly lower than those of solitary leiomyomas, whereas ERβ mRNA and protein levels in multiple leiomyomas were significantly higher than those in solitary leiomyomas, irrespectively of the menstrual cycle stage. In both multiple and solitary leiomyomas, ERα expression was higher than that of ERβ. E{sub 2} concentration in multiple and solitary leiomyomas correlated with that of ERα expression. ERα was present in nuclus and cytoplasma while estrogen receptor β localized only in nuclei in both multiple and solitary leiomyomas. Our findings suggest that the difference of ERα and ERβ expression between multiple and solitary leiomyomas may be responsible for the course of the disease subtypes. - Highlights: • In both multiple and solitary leiomyomas, ERα expression was higher than that of ERβ. • ERα was significantly lower, whereas ERβ was significantly higher in multiple leiomyomas than that in solitary leiomyomas. • The differential expression of ERα and ERβ may be responsible for the cause of the disease subtypes.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2015

Cryo-EM of the pathogenic VCP variant R155P reveals long-range conformational changes in the D2 ATPase ring

Single amino acid mutations in valosin containing protein (VCP/p97), a highly conserved member of the ATPases associated with diverse cellular activities (AAA) family of ATPases has been linked to a severe degenerative disease affecting brain, muscle and bone tissue. Previous studies have demonstrated the role of VCP mutations in altering the ATPase activity of the D2 ring; however the structural consequences of these mutations remain unclear. In this study, we report the three-dimensional (3D) map of the pathogenic VCP variant, R155P, as revealed by single-particle Cryo-Electron Microscopy (EM) analysis at 14 Å resolution. We show that the N-terminal R155P mutation induces a large structural reorganisation of the D2 ATPase ring. Results from docking studies using crystal structure data of available wild-type VCP in the EM density maps indicate that the major difference is localized at the interface between two protomers within the D2 ring. Consistent with a conformational change, the VCP R155P variant shifted the isoelectric point of the protein and reduced its interaction with its well-characterized cofactor, nuclear protein localization-4 (Npl4). Together, our results demonstrate that a single amino acid substitution in the N-terminal domain can relay long-range conformational changes to the distal D2 ATPase ring. Our results provide the first structural clues of how VCP mutations may influence the activity and function of the D2 ATPase ring. - Highlights: • p97{sub R155P} and p97{sub A232E} decrease the ability of p97 to bind to its co-factor Npl4. • p97{sub R155P} has a different isoelectric point than that of p97{sub R95G}, p97{sub A232E} and p97{sub WT}. • Mutation R155P changes principally the conformation of the D2 ring. • Mutation R155P modifies the interface between two protomers within the D2 ring.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2016

C2C12 myotubes inhibit the proliferation and differentiation of 3T3-L1 preadipocytes by reducing the expression of glucocorticoid receptor gene

Obesity is a well-established risk factor to health for its relationship with insulin resistance, diabetes and metabolic syndrome. Myocyte-adipocyte crosstalk model plays a significant role in studying the interaction of muscle and adipose development. Previous related studies mainly focus on the effects of adipocytes on the myocytes activity, however, the influence of myotubes on the preadipocytes development remains unclear. The present study was carried out to settle this issue. Firstly, the co-culture experiment showed that the proliferation, cell cycle, and differentiation of 3T3-L1 preadipocytes were arrested, and the apoptosis was induced, by differentiated C2C12 myotubes. Next, the sensitivity of 3T3-L1 preadipocytes to glucocorticoids (GCs), which was well known as cell proliferation, differentiation, apoptosis factor, was decreased after co-cultured with C2C12 myotubes. What's more, our results showed that C2C12 myotubes suppressed the mRNA and protein expression of glucocorticoid receptor (GR) in 3T3-L1 preadipocytes, indicating the potential mechanism of GCs sensitivity reduction. Taken together, we conclude that C2C12 myotubes inhibited 3T3-L1 preadipocytes proliferation and differentiation by reducing the expression of GR. These data suggest that decreasing GR by administration of myokines may be a promising therapy for treating patients with obesity or diabetes. - Highlights: • C2C12 myotubes inhibited proliferation and differentiation of 3T3-L1 preadipocytes. • C2C12 myotubes arrested cell cycle of 3T3-L1 preadipocytes. • C2C12 myotubes induced apoptosis of 3T3-L1 preadipocytes. • C2C12 inhibit 3T3-L1 cells by reducing the expression of glucocorticoid receptor gene.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2016

Priming with ceramide-1 phosphate promotes the therapeutic effect of mesenchymal stem/stromal cells on pulmonary artery hypertension

Some molecules enriched in damaged organs can contribute to tissue repair by stimulating the mobilization of stem cells. These so-called “priming” factors include bioactive lipids, complement components, and cationic peptides. However, their therapeutic significance remains to be determined. Here, we show that priming of mesenchymal stromal/stem cells (MSCs) with ceramide-1 phosphate (C1P), a bioactive lipid, enhances their therapeutic efficacy in pulmonary artery hypertension (PAH). Human bone marrow (BM)-derived MSCs treated with 100 or 200 μM C1P showed improved migration activity in Transwell assays compared with non-primed MSCs and concomitantly activated MAPK{sup p42/44} and AKT signaling cascades. Although C1P priming had little effect on cell surface marker phenotypes and the multipotency of MSCs, it potentiated their proliferative, colony-forming unit-fibroblast, and anti-inflammatory activities. In a monocrotaline-induced PAH animal model, a single administration of human MSCs primed with C1P significantly attenuated the PAH-related increase in right ventricular systolic pressure, right ventricular hypertrophy, and thickness of α-smooth muscle actin-positive cells around the vessel wall. Thus, this study shows that C1P priming increases the effects of MSC therapy by enhancing the migratory, self-renewal, and anti-inflammatory activity of MSCs and that MSC therapy optimized with priming protocols might be a promising option for the treatment of PAH patients. - Highlights: • Human BM-derived MSCs primed with C1P have enhanced migratory activity. • C1P primed MSCs increase proliferation, self-renewal, and anti-inflammatory capacity. • C1P priming enhances the therapeutic capacity of MSCs in a PAH animal model.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2016

Halofuginone alleviates acute viral myocarditis in suckling BALB/c mice by inhibiting TGF-β1

Viral myocarditis (VMC) is an inflammation of heart muscle in infants and young adolescents. This study explored the function of halofuginone (HF) in Coxsackievirus B3 (CVB3) -treated suckling mice. HF-treated animal exhibited higher survival rate, lower heart/body weight, and more decreased blood sugar concentration than CVB3 group. HF also reduced the expressions of interleukin(IL)-17 and IL-23 and the numbers of Th17 cells. Moreover, HF downregulated pro-inflammatory cytokine levels and increased anti-inflammatory cytokine levels. The expressions of transforming growth factor(TGF-β1) and nuclear factor kappa-light-chain-enhancer of activated B (NF-κB) p65/ tumor necrosis factor-α (TNF-α) proteins were decreased by HF as well. Finally, the overexpression of TGF-β1 counteracted the protection effect of HF in CVB3-treated suckling mice. In summary, our study suggests HF increases the survival of CVB3 suckling mice, reduces the Th17 cells and pro-inflammatory cytokine levels, and may through downregulation of the TGF-β1-mediated expression of NF-κB p65/TNF-α pathway proteins. These results offer a potential therapeutic strategy for the treatment of VMC. - Highlights: • Halofuginone (HF) increases the survival of suckling BALB/c mice infected with acute CVB3. • HF reduces the expression of Th17 cell markers (IL-17 and IL-23) and the number of CD4{sup +} IL17{sup +} cells. • Pro-inflammatory cytokines levels associated with myocarditis were reduced by HF in CVB3-treated suckling mice. • HF alleviates VMC via inhibition of TGF-β1-mediated NF-κB p65/TNF-α pathway.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2016

Mitochondrial DNA triplication and punctual mutations in patients with mitochondrial neuromuscular disorders

Mitochondrial diseases are a heterogeneous group of disorders caused by the impairment of the mitochondrial oxidative phosphorylation system which have been associated with various mutations of the mitochondrial DNA (mtDNA) and nuclear gene mutations. The clinical phenotypes are very diverse and the spectrum is still expanding. As brain and muscle are highly dependent on OXPHOS, consequently, neurological disorders and myopathy are common features of mtDNA mutations. Mutations in mtDNA can be classified into three categories: large-scale rearrangements, point mutations in tRNA or rRNA genes and point mutations in protein coding genes. In the present report, we screened mitochondrial genes of complex I, III, IV and V in 2 patients with mitochondrial neuromuscular disorders. The results showed the presence the pathogenic heteroplasmic m.9157G>A variation (A211T) in the MT-ATP6 gene in the first patient. We also reported the first case of triplication of 9 bp in the mitochondrial NC7 region in Africa and Tunisia, in association with the novel m.14924T>C in the MT-CYB gene in the second patient with mitochondrial neuromuscular disorder. - Highlights: • We reported 2 patients with mitochondrial neuromuscular disorders. • The heteroplasmic MT-ATP6 9157G>A variation was reported. • A triplication of 9 bp in the mitochondrial NC7 region was detected. • The m.14924T>C transition (S60P) in the MT-CYB gene was found.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2017

RIP2 deficiency attenuates cardiac hypertrophy, inflammation and fibrosis in pressure overload induced mice

Although the pathological cardiac hypertrophy presents a leading cause of morbidity and mortality worldwide, our knowledge of the molecular mechanisms underlying the disease is still poor. Here, we reported that receptor-interacting serine/threonine-protein kinase 2 (RIP2), promoting pro-inflammatory gene expression, enhanced the pathological cardiac hypertrophy in animals. The effects of RIP2 on the cardiac hypertrophy triggered by pathological stimuli have not been fully investigated. In our study, mice were subjected to aortic banding (AB) surgery to explore the pathological, echocardiographic and molecular mechanisms. RIP2 expressed highly in cardiomyocytes after AB operation in wild type (WT) mice. RIP2-knockout (KO) attenuated cardiac hypertrophy, inflammation and fibrosis in mice 4 weeks after AB-surgery. First, RIP2 knockout down-regulated hypertrophic markers of atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP) and β-myosin heavy chain (β-MHC) in the heart of AB-operated mice.in addition, RIP2-deficiency reduced toll-like receptor 4/myeloid differentiation factor 88/nuclear factor kappa B (TLR4/MyD88/NF-κB) activation, mitogen-activated protein kinases (MAPKs) phosphorylation and transforming growth factor-β1 (TGF-β1)/SMADs expressions, contributing to the suppression of inflammatory response and fibrosis, as further evidenced by down-regulated pro-inflammatory cytokines, including Tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6 and IL-18, as well as fibrosis markers of Collagen I, Collagen III and α-smooth muscle actin (α-SMA). Taken together, our data indicated that RIP2-deficience ameliorated cardiac hypertrophy, inflammation and fibrosis through modulating multiple signaling pathways. - Highlights: • Overexpression of RIP2 contributed to development of hypertrophic heart. • RIP2-knockout attenuates cardiac injury and dysfunction in hypertrophic heart. • RIP2-deficience alleviates inflammation in heart of hypertrophic mice. • RIP2-deletion inhibits fibrosis in the heart of hypertrophic mice.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2017

Antidiabetic effect of gomisin N via activation of AMP-activated protein kinase

Highlights: • Gomisin N activated AMPK/Akt signaling in C2C12 myotubes. • Gomisin N stimulated glucose uptake in C2C12 myotubes. • Gomisin N promoted mitochondria biogenesis and fatty acid oxidation in C2C12 myotubes. • Gomisin N reduced hyperglycemia and improved glucose tolerance in HFD obese mice. Gomisin N (GN) is a lignan derived from Schisandra chinensis. AMP-activated kinase (AMPK) has gained attention as a therapeutic target for the treatment of metabolic syndrome. Previously, we reported that GN activated the AMPK pathway and ameliorated high-fat diet (HFD)-induced hepatic steatosis. In this study, we investigated the anti-diabetic effects of GN in C2C12 myotubes and HFD obese mice. GN enhanced the phosphorylation of AMPK/acetyl-CoA carboxylase (ACC) and Akt. In addition, GN promoted glucose uptake in C2C12 myotubes, which was accompanied by the translocation of glucose transporter 4 (GLUT4) to the plasma membrane. Treatment with compound C, an AMPK inhibitor, suppressed GN-mediated stimulation of glucose uptake. Furthermore, GN increased the expression of mitochondria biogenesis and fatty acid oxidation genes in C2C12 myotubes. In the in vivo study, administration of GN to HFD mice decreased the levels of fasting blood glucose and insulin, and improved glucose tolerance in HFD obese mice. GN administration rescued the decreased phosphorylation of AMPK and Akt and stimulated the expression of mitochondria biogenesis genes in the skeletal muscle of HFD mice. These findings suggested that GN exerted anti-hyperglycemic effects through AMPK activation.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2017

A novel mitochondria-targeted two-photon fluorescent probe for dynamic and reversible detection of the redox cycles between peroxynitrite and glutathione

Highlights: • We report a two-photon fluorescent probe (TP-Se) for optical imaging. • TP-Se can monitor reversibly changes in ONOO{sup −}/GSH levels in mitochondria. • TP-Se will lead to significant development on redox events in cellular redox regulation. Redox homeostasis is important for maintenance of normal physiological functions within cells. Redox state of cells is primarily a consequence of precise balance between levels of reducing equivalents and reactive oxygen species. Redox homeostasis between peroxynitrite (ONOO{sup −}) and glutathione (GSH) is closely associated with physiological and pathological processes, such as prolonged relaxation in vascular tissues and smooth muscle preparations, attenuation of hepatic necrosis, and activation of matrix metalloproteinase-2. We report a two-photon fluorescent probe (TP-Se) based on water-soluble carbazole-based compound, which integrates with organic selenium, to monitor changes in ONOO{sup −}/GSH levels in cells. This probe can reversibly respond to ONOO{sup −} and GSH and exhibits high selectivity, sensitivity, and mitochondrial targeting. The probe was successfully applied to visualize changes in redox cycles during ONOO{sup −} outbreak and antioxidant GSH repair in cells. The probe will lead to significant development on redox events involved in cellular redox regulation.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2017

The reason for a high Ca2+-sensitivity associated with Arg91Gly substitution in TPM2 gene is the abnormal behavior and high flexibility of tropomyosin during the ATPase cycle

Highlights: • Mutation R91G initiates abnormally high flexibility of β-tropomyosin (TM). • Troponin moves R91G-TM to the blocked position at low Ca{sup 2+}. • This mutation does not alter the ability of troponin to switch off actin monomers. • R91G-TM is located near the open position during the ATPase cycle at low Ca{sup 2+}. • Mutation R91G increases the fraction of rigor myosin heads at low Ca{sup 2+}. Substitution of Arg for Gly residue in 91th position in β-tropomyosin caused by a point mutation in TPM2 gene is associated with distal arthrogryposis, characterized by a high Ca{sup 2+}-sensitivity of myofilament and contracture syndrome. To understand the mechanisms of this defect, we studied multistep changes in mobility and spatial arrangement of tropomyosin, actin and myosin heads during the ATPase cycle in reconstituted ghost fibres, using the polarized fluorescence microscopy. The mutation was shown to markedly decrease the bending stiffness of β-tropomyosin in the thin filaments. In the absence of the myosin heads the mutation did not alter the ability of troponin to shift tropomyosin to the blocked position and to switch actin monomers off at low Ca{sup 2+}. During the ATPase cycle the movement of the mutant tropomyosin is restrained, it is located near the open position, which allows strong binding of the myosin heads to actin even at low Ca{sup 2+}. This may be the reason for both high Ca{sup 2+}-sensitivity and contractures associated with the Arg91Gly mutation. The use of reagents that decrease the Ca{sup 2+}sensitivity of the troponin complex may not be appropriate to restore muscle function in patients with this mutation.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2018

Role of inositol 1,4,5-trisphosphate receptor type 1 in ATP-induced nuclear Ca2+ signal and hypertrophy in atrial myocytes

Highlights: • IP{sub 3} receptor type 1 (IP{sub 3}R1) are expressed in atrial cell perinucleus. • IP{sub 3}R1 mediates ATP-induced sustained nuclear Ca{sup 2+} increase in HL-1 atrial cells. • IP{sub 3}R1 contributes to higher sensitivity of nuclear release sites upon IP{sub 3} increase. • Larger Ca{sup 2+} content in perinuclear store of atrial cells involves IP{sub 3}R1. • IP{sub 3}R1 signaling may play a role in ATP-induced atrial cell hypertrophy. Inositol 1,4,5-trisphosphate receptor type 1 (IP{sub 3}R1) is expressed in atrial muscle, but not in ventricle, and they are abundant in the perinucleus. We investigated the role of IP{sub 3}R1 in the regulations of local Ca{sup 2+} signal and cell size in HL-1 atrial myocytes under stimulation by IP{sub 3}-generating chemical messenger, ATP. Assessment of nuclear and cytosolic Ca{sup 2+} signal using confocal Ca{sup 2+} imaging revealed that IP{sub 3} generation by ATP (1 mM) induced monophasic nuclear Ca{sup 2+} increase, followed by cytosolic Ca{sup 2+} oscillation. Genetic knock-down (KD) of IP{sub 3}R1 eliminated the monophasic nuclear Ca{sup 2+} signal and slowed the cytosolic Ca{sup 2+} oscillation upon ATP exposure. Prolonged application of ATP as well as other known hypertrophic agonists (endothelin-1 and phenylephrine) increased cell size in wild-type cells, but not in IP{sub 3}R1 KD cells. Our data indicate that IP{sub 3}R1 mediates sustained elevation in nuclear Ca{sup 2+} level and facilitates cytosolic Ca{sup 2+} oscillation upon external ATP increase, and further suggests possible role of nuclear IP{sub 3}R1 in atrial hypertrophy.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2014

Bladder Function Preservation With Brachytherapy, External Beam Radiation Therapy, and Limited Surger in Bladder Cancer Patients: Long-Term Results

Purpose: To report long-term results of a bladder preservation strategy for muscle-invasive bladder cancer (MIBC) using external beam radiation therapy and brachytherapy/interstitial radiation therapy (IRT). Methods and Materials: Between May 1989 and October 2011, 192 selected patients with MIBC were treated with a combined regimen of preoperative external beam radiation therapy and subsequent surgical exploration with or without partial cystectomy and insertion of source carrier tubes for afterloading IRT using low dose rate and pulsed dose rate. Data for oncologic and functional outcomes were prospectively collected. The primary endpoints were local recurrence-free survival (LRFS), bladder function preservation survival, and salvage cystectomy-free survival. The endpoints were constructed according to the Kaplan-Meier method. Results: The mean follow-up period was 105.5 months. The LRFS rate was 80% and 73% at 5 and 10 years, respectively. Salvage cystectomy-free survival at 5 and 10 years was 93% and 85%. The 5- and 10-year overall survival rates were 65% and 46%, whereas cancer-specific survival at 5 and 10 years was 75% and 67%. The distant metastases-free survival rate was 76% and 69% at 5 and 10 years. Multivariate analysis revealed no independent predictors of LRFS. Radiation Therapy Oncology Group grade ≥3 late bladder and rectum toxicity were recorded in 11 patients (5.7%) and 2 patients (1%), respectively. Conclusions: A multimodality bladder-sparing regimen using IRT offers excellent long-term oncologic outcome in selected patients with MIBC. The late toxicity rate is low, and the majority of patients preserve their functional bladder.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

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