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Evidence is provided that the fibroproliferative actions of TGF-β are dependent on a metabolic adaptation that sustains pathologic growth. Specifically, profibrotic TGF-β signaling is shown to require fatty acid synthase (FASN), an essential anabolic enzyme responsible for the de novo synthesis of fatty acids. With the use of pharmacologic and genetic approaches, we show that TGF-β-stimulated FASN expression is independent of Smad2/3 and is mediated via mammalian target of rapamycin complex 1. In the absence of FASN activity or protein, TGF-β-driven fibrogenic processes are reduced with no apparent toxicity. Furthermore, as increased FASN expression was also observed to correlate with the degree of lung fibrosis in bleomycin-treated mice, inhibition of FASN was examined in a murine-treatment model of pulmonary fibrosis. Remarkably, inhibition of FASN not only decreased expression of profibrotic targets, but lung function was also stabilized/improved, as assessed by peripheral blood oxygenation.--Jung, M.-Y., Kang, J.-H., Hernandez, D. M., Yin, X., Andrianifahanana, M., Wang, Y., Gonzalez-Guerrico, A., Limper, A. H., Lupu, R., Leof, E. B. Fatty acid synthase is required for profibrotic TGF-β signaling. [ABSTRACT FROM AUTHOR]

TGF-β is considered a master switch in the pathogenesis of organ fibrosis. The primary mediators of this activity are the SMAD proteins, particularly SMAD3. In the current study, we have developed a cell-penetrating peptide (CPP) conjugate of the HIV TAT protein that is fused to an aminoterminal sequence of sorting nexin 9 (SNX9), which was previously shown to bind phosphorylated SMAD3 (pSMAD3). We determined that specifically preventing the nuclear import of pSMAD3 using the TAT-SNX9 peptide inhibited profibrotic TGF-β activity in murine cells and human lung fibroblasts as well as in vivo with no demonstrable toxicity. TGF-β signaling mediated by pSMAD2, bone morphogenetic protein 4 (BMP4), EGF, or PDGF was unaffected by the TAT-SNX9 peptide. Furthermore, while the TAT-SNX9 peptide prevented TGF-β's profibrotic activity in vitro as well as in 2 murine treatment models of pulmonary fibrosis, a 3-amino acid point mutant that was unable to bind pSMAD3 proved ineffective. These findings indicate that specifically targeting pSMAD3 can ameliorate both the direct and indirect fibroproliferative actions of TGF-β. [ABSTRACT FROM AUTHOR]

We report on an unusual case with infiltrating extradural spinal angiolipoma. Most spinal angiolipomas involve the thoracic spine and infiltrating ones are also located mainly at the thoracic levels rather than lumbar lesion. In particular, there are few cases of lumbar extradural infiltrating type spinal angiolipoma. One case is that of a 52-year-old female with infiltrating extradural spinal angiolipoma involving lumbar 4 (L4) vertebra, who underwent a L4−5 laminectomy and surgical removal of the tumor. We achieved satisfactory results with surgical treatment of the patient. Spinal angiolipoma has a benign course with a good postoperative outcome. [ABSTRACT FROM AUTHOR]

CTGF (connective tissue growth factor) is widely regarded as an important amplifier of the profibrogenic action of TGF-β (transforming growth factor β) in a variety of tissues, although the precise mechanism of how the TGF-β signalling pathways modulate CTGF expression remains unclear. In the present study, the role of PKCδ (protein kinase Cδ) in TGF-β1-mediated CTGF expression was investigated using HepG2 cells. TGF- β1 treatment specifically elevated PKCδ activation and CTGF expression. In contrast, blockade of PKCδ by the selective inhibitor Rottlerin or by siRNA knockdown significantly reduced TGF-β1-induced CTGF production. The regulatory mechanism was further demonstrated in HepG2 cells whereby TGF-β1- induced PKCδ activation negatively regulated the nuclear levels of PPM1A (protein phosphatase, Mg2+ /Mn2+ dependent, 1A) through the RhoA/ROCK (Rho-associated kinase) pathway. Moreover, we showed that both Smad signalling and the PKCδ pathway appeared to be stimulated by TGF-β1 in parallel. Time course assessments indicated that PKCδ signalling may have a function in maintaining nuclear phospho-Smads at a maximal level. The collective results of the present study demonstrated that PKCδ-stimulated RhoA/ROCK activation resulted in a reduction in PPM1A, thereby up-regulating Smad-dependent gene induction for extended periods. These findings indicated that PKCδ plays a critical role in TGF-β1-induced CTGF production in HepG2 cells. [ABSTRACT FROM AUTHOR]

Background: Bee venom has been used to relieve pain and to treat inflammatory diseases, including rheumatoid arthritis, in humans. To better understand the mechanisms of the anti-inflammatory and anti-atherosclerosis effect of bee venom, gel electrophoresis and mass spectrometry were used to identify proteins whose expression was altered in human Vascular Smooth Muscle Cells (hVSMCs) stimulated by tumor necrosis factor alpha after 12 h in the presence of melittin. Results: To obtain valuable insights into the anti-inflammatory and anti-atherosclerosis mechanisms of melittin, two-dimensional (2-D) gel electrophoresis and MALDI-TOF/TOF were used. The proteome study, we showed 33 significant proteins that were differentially expressed in the cells treated with tumor necrosis factor alpha and melittin. Thirteen proteins were significantly increased in the cells treated with tumor necrosis factor alpha, and those proteins were reduced in the cells treated with melittin. Five of the proteins that showed increased expression in the cells treated with tumor necrosis factor alpha are involved in cell migration, including calreticulin, an essential factor of development that plays a role in transcription regulation. The proteins involved in cell migration were reduced in the melittin treated cells. The observed changes in the expression of GRP75, prohibitin, and a select group of other proteins were validated with reverse transcribed-PCR. It was confirmed that the observed change in the protein levels reflected a change in the genes level. In addition, the phosphorylation of EGFR and ERK was validated by analyzing the protein pathway. Conclusion: Taken together, these data established that the expression of some proteins was significantly changed by melittin treatment in tumor necrosis factor alpha stimulated the cells and provided insights into the mechanism of the melittin function for its potential use as an anti-inflammatory agent. [ABSTRACT FROM AUTHOR]

The synthetic derivative of ascochlorin, 4-O-carboxymethyl ascochlorin (AS-6) is an agonist of the nuclear hormone receptor PPARγ and has been shown to induce differentiation in mouse pre-adipocytes and to ameliorate type II diabetes in a murine model. AS-6 was cytotoxic when added at micromolar concentrations to cultures of three different human cancer cell lines. We used gel electrophoresis and mass spectrometry to identify proteins with altered expression in human hepatocarcinoma cells (HepG2) cells after 12 h in the presence of AS-6 and found 58 proteins that were differentially expressed. Many of the proteins showing increased expression in cells treated with AS-6 are involved in protein quality control, including glucoseregulated protein 78 (GRP78/BiP), a regulator of ER stress responses, and the transcriptional regulator CHOP, which mediates ER stress-induced apoptosis. Cells treated with AS-6 undergo an autophagic response accompanied by increased expression of beclin1, ATG5, and LC3-II and autophagosome formation marked by the appearance of large vesicles containing LC3-II. Grp78 induction was inhibited when the PPARγ antagonist, GW9662, was added together with AS-6, and autophagy and cell death were partially blocked. 3-methyl-adenine (3-MA), an inhibitor of phosphatidyl inositol 3-kinase (PI3-kinase) prevented induction of ATG5 and activation of LC3-II and blocked autophagosome formation. 3-MA also blocked induction of GRP78 and CHOP, suggesting that PI3- kinase, which is known to mediate ER stress-induced autophagy, also plays a role in initiating apoptosis in response to ER stress. Together these data establish that the cytotoxicity of AS-6 operates by a mechanism dependent on ER stress-induced autophagy and apoptosis. [ABSTRACT FROM AUTHOR]

This article examines the correlates of nonresponse for self-administered questionnaire (SAQ) sections by comparing two General Social Survey (GSS) years, 2000 and 2002, during which the GSS switched the paper-and-pencil personal interview (PAPI) and SAQ to the computer-assisted personal interview (CAPI) and computer-assisted self-administered interview (CASI) format. The authors find that CASI not only lowers the supplemental response rate but also changes the dynamics of who responds. Unlike PAPI and SAQ data collection in 2000, even those aged 45-64 were less likely to respond to the CASI supplemental survey compared to CAPI in 2002. Compared to Whites, Blacks and other ethnic groups were more likely to be nonrespondents with CASI. Researchers should be more attentive to the potential bias of supplemental nonresponse in CASI. [ABSTRACT FROM AUTHOR]

Autophagosomes and their precursors are best defined by electron microscopy but may also be traced in living cells based on the distribution of specific autophagy molecules, LC3, the most commonly examined autophagy marker in mammalian cells, labels structures that are frequently manifested as dots or rings using light microscopy; however, the nature of these structures is not entirely clear. We reported here a novel approach to examine the LC3-positive compartment in cell-free lysates, which revealed that they were actually tubulovesicular structures with considerable heterogeneity. Using affinity purification, we isolated these membranes for electron microscopy, which indicated that they possessed ultrastructural features consistent with autophagosomal membranes at various maturation stages. Further biochemical and proteomics analyses demonstrated the presence of multiple autophagy-related and other functional molecules. The different distribution patterns of Atg5, Atgl6, Atg9, and p62/SQSTM1 on the LC3-positive compartment provided new clues on how these molecules might be involved in the dynamics of the autophagosomal membranes. Finally, several morphologically unique groups of LC3-positive membranes were categorized. Their topological configurations suggested that double-membrane vesicles could be derived from single membrane compartments via different means, including tubule-to-vesicle conversion, whose presence was supported by live cell imaging. These findings thus provide new information on the dynamics of the autophagosomal compartment. [ABSTRACT FROM AUTHOR]

McDonald and Moffitt's (1980) decomposition method for Tobit coefficients disaggregates the total changes in a censored outcome variable into the changes in the probability of attaining noncensored values and the changes in the noncensored values themselves. McDonald and Moffitt, however, did not highlight two limitations of this decomposition, and sociological applications of the Tobit decomposition that do not acknowledge these limitations have been misleading. First, the decomposition ratio of the two effects depends on the choice of an observation point in the sample. Some sociological studies invalidly generalized a decomposition at the mean point of the sample to the whole sample. Second, once the observation point is fixed, the decomposition ratio is the same across all coefficients or across all predictors. That is, the two effects remain proportionally constant, but studies often erroneously assume they differ across predictors. Further implications are discussed in relation to other selection bias models. [ABSTRACT FROM AUTHOR]

Objectives. Faced with aging societies, there is an immense need to better understand the nature of volunteering outside advanced Western industrial countries. As a case of a rapidly aging society, we identify robust factors associated with elderly volunteering in Korea in terms of a resource framework. Methods. Data were derived from the Social Statistics Survey conducted by the Korea National Statistical Office in 1999 (N = 7,135) and 2003 (N = 8,371). We first determined overall and age-related volunteer rates for Korea compared to the United States. Using logistic regression, we then examined the effects of human, cultural, and social capital variables on volunteering. Results. Approximately 6% of Koreans aged 65 years and older participate in volunteer programs. All human capital variables are positively related with volunteering. For cultural capital, those who identify their religion as Buddhism or Catholicism are more likely to volunteer than those who have no religion. But surprisingly, Protestantism does not consistently promote volunteering across both years. For social capital, older adults who live alone or with a spouse are more likely to volunteer than those living with both a spouse and children. Discussion. In contrast to human capital, cultural and social capital on elderly volunteering appears to be contoured by social contexts. [ABSTRACT FROM AUTHOR]

TGF-β plays a central role in the pathogenesis of fibroproliferative disorders. Defining the exact underlying molecular basis is therefore critical for the development of viable therapeutic strategies. Here, we show that expression of the facilitative glucose transporter 1 (GLUT1) is induced by TGF-β in fibroblast lines and primary cells and is required for the profibrotic effects of TGF-β. In addition, enhanced GLUT1 expression is observed in fibrotic areas of lungs of both patients with idiopathic pulmonary fibrosis and mice that are subjected to a fibrosis-inducing bleomycin treatment. By using pharmacologic and genetic approaches, we demonstrate that up-regulation of GLUT1 occurs via the canonical Smad2/3 pathway and requires autocrine activation of the receptor tyrosine kinases, platelet-derived and epidermal growth factor receptors. Engagement of the common downstream effector PI3K subsequently triggers activation of the MEK and mammalian target of rapamycin complex 2, which cooperate in regulating GLUT1 expression. Of note, inhibition of GLUT1 activity and/or expression is shown to impair TGF-β-driven fibrogenic processes, including cell proliferation and production of profibrotic mediators. These findings provide new perspectives on the interrelation of metabolism and profibrotic TGF-β signaling and present opportunities for potential therapeutic intervention.--Andrianifahanana, M., Hernandez, D. M., Yin, X., Kang, J.-H., Jung, M.-Y., Wang, Y., Yi, E. S., Roden, A. C., Limper, A. H., Leof, E. B. Profibrotic up-regulation of glucose transporter 1 by TGF-β involves activation of MEK and mammalian target of rapamycin complex 2 pathways. [ABSTRACT FROM AUTHOR]

Autophagy can be activated via MTORC1 down-regulation by amino acid deprivation and by certain chemicals such as rapa-mycin, torin, and niclosamide. Lysosome is the degrading machine for autophagy but has also been linked to MTORC1 activation through the Rag/RRAG GTPase pathway. This association raises the question of whether lysosome can be involved in the initiation of autophagy. Toward this end, we found that niclosamide, an MTORC1 inhibitor, was able to inhibit lysosome degradation and increase lysosomal permeability. Niclosamide was ineffective in inhibiting MTORC1 in cells expressing constitutively activated Rag proteins, suggesting that its inhibitory effects were targeted to the Rag-MTORC1 signaling system. This places niclosamide in the same category of bafilomycin A1 and concanamycin A, inhibitors of the vacuolar H+-ATPase, for its dependence on Rag GTPase in suppression of MTORC1. Surprisingly, classical lysosome inhibitors such as chloroquine, E64D, and pepstatin A were also able to inhibit MTORC1 in a Rag-dependent manner. These lysosome inhibitors were able to activate early autophagy events represented by ATG16L1 and ATG12 puncta formation. Our work established a link between the functional status of the lysosome in general to the Rag-MTORC1 signaling axis and autophagy activation. Thus, the lysosome is not only required for autophagic degradation but also affects autophagy activation. Lysosome inhibitors can have a dual effect in suppressing autophagy degradation and in initiating autophagy. [ABSTRACT FROM AUTHOR]

Subjective sexual well-being refers to the cognitive and emotional evaluation of an individual's sexuality. This study examined subjective sexual well-being, explored its various aspects, examined predictors across different cultures, and investigated its possible associations with overall happiness and selected correlates, including sexual dysfunction. Data were drawn from the Global Study of Sexual Attitudes and Behaviors, a survey of 27,500 men and women aged 40–80 years in 29 countries. The cross-national variation of four aspects of sexual well-being (the emotional and physical satisfaction of sexual relationships, satisfaction with sexual health or function, and the importance of sex in one's life) was explored using cluster analysis, and relationships among sexual well-being, general happiness, and various correlates were examined using ordinary least squares regression and ordered logistic regression. Results from the cluster analysis identified three clusters: a gender-equal regime and two male-centered regimes. Despite this cultural variation, the predictors of subjective sexual well-being were found to be largely consistent across world regions. [ABSTRACT FROM AUTHOR]