Iron-Induced Oxidative Injury Differentially Regulates PI3K/Akt/GSK3β Pathway in Synaptic Endings from Adult and Aged Rats

In this work we study the state of phosphoinositide-3-kinase/Akt/glycogen synthase kinase 3 beta (PI3K/Akt/GSK3 beta) signaling during oxidative injury triggered by free iron using cerebral cortex synaptic endings isolated from adult (4-month-old) and aged (28-month-old) rats. Synaptosomes were exposed to FeSO4 (50 microM) for different periods of time and synaptosomal viability and the state of the PI3K/Akt/GSK3 beta pathway were evaluated in adult and aged animals. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide reduction and lactate dehydrogenase leakage were significantly affected in both age groups. However, aged animals showed a greater susceptibility to oxidative stress. In adults, Akt was activated after a brief exposure time (5 min), whereas in aged animals activation occurred after 5 and 30 min of incubation with the metal ion. GSK3 beta phosphorylation showed the same activation pattern as that observed for Akt. Both Akt and GSK3 beta phosphorylation were dependent on PI3K activation. Extracellular signal-regulated kinases 1 and 2 (ERK1/2) activation was temporally coincident with Akt activation and was PI3K dependent in adults, whereas ERK1/2 activation in aged rats was higher than that observed in adults and showed no dependence on PI3K activity. We demonstrate here that synaptic endings from adult and aged animals subjected to iron-induced neurotoxicity show a differential profile in the activation of PI3K/Akt/GSK3 beta. Our results strongly suggest that the increased susceptibility of aged animals to oxidative injury provokes a differential modulation of key signaling pathways involved in synaptic plasticity and neuronal survivalFil: Uranga, Romina Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Investigaciones Bioquímicas de Bahía Blanca. Universidad Nacional del Sur. Instituto de Investigaciones Bioquímicas de Bahía Blanca; ArgentinaFil: Giusto, Norma Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Investigaciones Bioquímicas de Bahía Blanca. Universidad Nacional del Sur. Instituto de Investigaciones Bioquímicas de Bahía Blanca; ArgentinaFil: Salvador, Gabriela Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Investigaciones Bioquímicas de Bahía Blanca. Universidad Nacional del Sur. Instituto de Investigaciones Bioquímicas de Bahía Blanca; Argentin

Institutional diversity in the euro area: Any evidence of convergence?

In recent years differences in the institutional structure across euro area countries are becoming a cause of concern both for some individual Member States and for the functioning of the Economic and Monetary Union (EMU). From a global competitiveness perspective, we deal with the diversity in the institutional environment in the EMU. In particular, we assess whether the changes in the state of institutions provide convergence across euro area countries between 2006 and 2015. In addition, among the institutional indicators considered, we compute which institutional aspect contributes more to overall inequality in the state of institutions, as well as the contribution of each country to inequality considering as benchmark the country with the highest institutional quality. According to these country contributions, we highlight distinct patterns of convergence between ‘core’ and ‘periphery’ euro area countries and raise potential links between the institutional changes across euro area countries and both the differences in the intensity of the financial and economic crisis, and the policy responses in terms of fiscal consolidation applied by the respective national governments.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Does economic freedom increase income inequality? Evidence from the EU countries

Over the past decades there have been considerable changes in policies and institutions in favor of economic freedom in the EU countries. This trend coincides with widespread increases in income inequality in numerous member states. To what extent does economic freedom encourage inequality? This paper examines the relationship between economic freedom and income inequality in the EU countries using panel data for the 2000s. The empirical evidence suggests that economic freedom seems to entail greater income inequality. However, not all areas of economic freedom affect income distribution similarly. While government size and regulation appear to be robustly associated with income inequality, legal system and property rights, sound money, and freedom to trade internationally seem not to be significantly related with income distribution in the European context.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Disparities in entrepreneurship indicators across EU countries

The levels and characteristics of entrepreneurship differ widely across EU member countries due to diverse cultural, educational, economic-financial and institutional reasons. Taking as reference data provided by the Global Entrepreneurship Monitor (GEM), this paper analyzes the disparities in entrepreneurship indicators among the EU member countries in 2007 and 2013, highlighting the most significant changes occurred during the Great Recession. For this purpose, some of the major indices of inequality have been calculated, namely the Gini, Theil and Atkinson indices. In addition, the change in the Gini coefficient between these two years is additively decomposed into mobility and progressivity components, and growth incidence curves of some key indicators of entrepreneurial activity are estimated. Overall, we find that inequality among countries in most entrepreneurial attitude and aspiration indicators tends to diminish over the period 2007-2013. For all indicators the reduction is more generalized across the efficiency-driven economies than across the innovation-driven economies.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Entrepreneurship and Economic Liberalization in the OECD Countries

Entrepreneurship displays remarkable differences across countries because of diverse factors. In this sense, it is frequently argued that economic liberalization encourages entrepreneurship. In this paper we address the extent to which economic freedom, understood as market economy oriented institutions and policies, matters for entrepreneurial activity through a panel data analysis for 78 countries during the period 2001-2012. We examine the relationship between the Fraser Institute’s economic freedom index and its five areas, and three entrepreneurial activity indicators from the Global Entrepreneurship Monitor, namely total entrepreneurial activity, necessity entrepreneurship and opportunity entrepreneurship. Economic freedom seems to increase opportunity entrepreneurship and decrease necessity entrepreneurship. Focusing on the OECD countries, we highlight that economic freedom is positively associated with entrepreneurship. In terms of entrepreneurship motivation, we find that a more flexible regulation of credit, labor and business, as well as entrepreneurial attitudes, may contribute to enhance opportunity entrepreneurshipUniversidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

Examinig the roloe of economic liberalization in entrepeneurship: a cross-country study

In the last few decades some authors have underlined the role of institutions and policies for entrepreneurship. North (1990) underlines that entrepreneurs are the main agents of change and that organizations, such as firms set up by entrepreneurs, adapt their activities and strategies to fit the opportunities and limitations provided through formal and informal institutional frameworks. Baumol (1990) hypothesizes that entrepreneurial individuals channel their efforts in different directions depending on the quality of prevailing economic, political, and legal institutions. Sobel (2008) asserts that better institutions have both more productive entrepreneurship and also less unproductive entrepreneurship. He stresses that the best path to foster entrepreneurship is through institutional reforms that constrain or minimize the role of government. In this context, economic freedom may be seen as a significant aspect for entrepreneurial activity and it is frequently argued that economic liberalization encourages entrepreneurship. In this paper we address the extent to which economic freedom, understood as market economy oriented institutions and policies, matters for entrepreneurial activityUniversidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Expansion of the current methodology for the study of the short-term liquidity problems in a sector

Purpose: The aim of this work consists of defining and applying a new methodology for the calculation of short-term financial ratios that more reliably approximate the solvency of a sector. Design/methodology: We begin with a classic sector analysis and propose the creation of ratios that limit the debt repayment on an individual level and that do not imply the compensation of aggregate balances, as occurs with the current formulas of calculation. Findings: The new methodology more reliably approximates the solvency of a sector by being able to estimate with greater precision its global capacity for short-term debt repayment. Research limitations: The limitations to the proposed sector ratios are the same as the limitations of the customary individual ratios. Therefore, to offer an example, the ratios do not correct the assumption that the only source of resources to meet current liabilities is made up by available and liquid assets. In other words, no new tools are proposed to include future income from sales by the companies. Practical implications: To be able to study the solvency of the different sectors that make up the economy with more uniform criteria. Social implications: The information provided by the new ratios obtained in this work proves to be relevant information in the case of wanting to determine the degree of dependence of companies in a sector on financial institutions, or in the case of wanting to determine the degree of dependence on aid in a subsidized sector. Originality/value: The proposal of new tools that go beyond the current limitations.Peer Reviewe