Household water consumption: Insight from a survey in Greece and Poland

© 2015 The Authors. Published by Elsevier Ltd. Determining the behavior of domestic water consumers can facilitate a more proactive approach to water demand management, and serves as the foundation for the development of any intervention strategies that seek to bring about sustained and substantial reductions in domestic water consumption. As part of the European Union (EU) funded project Integrated Support System for Efficient Water Usage and Resources Management (ISS-EWATUS), a household water consumption survey was administered to address the question of how water was used within the home in the EU. The survey was distributed by the University of Thessaly in Greece, and the Institute for Ecology of Industrial Areas in Poland. This paper represents the research output of the survey, including the analysis of three major elements pertinent to the behavior of domestic water consumers: end use behaviors; socio-demographic and property characteristics; and psychosocial constructs such as attitudes and beliefs

Household water consumption: Insight from a survey in Greece and Poland

© 2015 The Authors. Published by Elsevier Ltd. Determining the behavior of domestic water consumers can facilitate a more proactive approach to water demand management, and serves as the foundation for the development of any intervention strategies that seek to bring about sustained and substantial reductions in domestic water consumption. As part of the European Union (EU) funded project Integrated Support System for Efficient Water Usage and Resources Management (ISS-EWATUS), a household water consumption survey was administered to address the question of how water was used within the home in the EU. The survey was distributed by the University of Thessaly in Greece, and the Institute for Ecology of Industrial Areas in Poland. This paper represents the research output of the survey, including the analysis of three major elements pertinent to the behavior of domestic water consumers: end use behaviors; socio-demographic and property characteristics; and psychosocial constructs such as attitudes and beliefs

Mitochondrial Respiration Regulates Adipogenic Differentiation of Human Mesenchymal Stem Cells

Human mesenchymal stem cells (MSCs) are adult multipotent stem cells which can be isolated from bone marrow, adipose tissue as well as other tissues and have the capacity to differentiate into a variety of mesenchymal cell types such as adipocytes, osteoblasts and chondrocytes. Differentiation of stem cells into mature cell types is guided by growth factors and hormones, but recent studies suggest that metabolic shifts occur during differentiation and can modulate the differentiation process. We therefore investigated mitochondrial biogenesis, mitochondrial respiration and the mitochondrial membrane potential during adipogenic differentiation of human MSCs. In addition, we inhibited mitochondrial function to assess its effects on adipogenic differentiation. Our data show that mitochondrial biogenesis and oxygen consumption increase markedly during adipogenic differentiation, and that reducing mitochondrial respiration by hypoxia or by inhibition of the mitochondrial electron transport chain significantly suppresses adipogenic differentiation. Furthermore, we used a novel approach to suppress mitochondrial activity using a specific siRNA-based knockdown of the mitochondrial transcription factor A (TFAM), which also resulted in an inhibition of adipogenic differentiation. Taken together, our data demonstrates that increased mitochondrial activity is a prerequisite for MSC differentiation into adipocytes. These findings suggest that metabolic modulation of adult stem cells can maintain stem cell pluripotency or direct adult stem cell differentiation

Inhibition of mitochondrial oxidation prevents adipogenic differentiation of hMSCs.

<p><b>A)</b> 100 nM rotenone decreased the baseline oxygen consumption rate (OCR) and maximal respiration capacity (induced by FCCP treatment) in hMSCs (n = 7 for each group). <b>B)</b> Oil Red O staining showed that chronic treatment with 100 nM Rotenone inhibited adipogenic differentiation with a significant decrease in the percentage of surface area stained with Oil Red O (n = 5 for DMSO control and n = 4 for 100 nM Rotenone treatment). <b>C)</b> Real-time RT-PCR data confirm the inhibition on hMSCs adipogenic differentiation by rotenone as adiponectin levels are significantly lower after rotenone treatment (n = 3 for each group). <b>D)</b> Importantly, chronic treatment with 100 nM rotenone for 7 days during adipogenic differentiation did not result in ATP depletion, thus suggesting that the concentration of rotenone used in our studies was not toxic (n = 3 for each group).</p

Adipogenic differentiation enhances mitochondrial oxidation in hMSCs.

<p><b>A)</b> Bone marrow-derived hMSCs underwent adipogenic differentiation using 500 nM Isobutylmethylxanthine, 1 µM Dexamethasone, 50 µM Indomethacin and 5 µg/ml Insulin. Oil Red O staining was used to confirm the adipogenic differentiation of hMSCs at day 21 (n = 4 and representative pictures are shown). <b>B)</b> Real-time RT-PCR confirmed the upregulation of the adipogenic differentiation marker adiponectin (n = 5 for each group). <b>C)</b> Oxygen consumption rate (OCR) increases gradually during adipogenic differentiation. Furthermore, the maximal OCR as elicited by treatment with the mitochondrial uncoupler FCCP (2 µM) is also increased during adipogenic differentiation (n≥5 for each group). <b>D)</b> Lactate production was decreased after adipogenic differentiation, indicating decreased glycolysis upon differentiation (n = 9 for each group). <b>E)</b> Cellular ATP content normalized to total cellular protein decreased gradually during 7 days of adipogenic differentiation (n = 5 for each group).</p

Mitochondrial Respiration Regulates Adipogenic Differentiation of Human Mesenchymal Stem Cells

<div><p>Human mesenchymal stem cells (MSCs) are adult multipotent stem cells which can be isolated from bone marrow, adipose tissue as well as other tissues and have the capacity to differentiate into a variety of mesenchymal cell types such as adipocytes, osteoblasts and chondrocytes. Differentiation of stem cells into mature cell types is guided by growth factors and hormones, but recent studies suggest that metabolic shifts occur during differentiation and can modulate the differentiation process. We therefore investigated mitochondrial biogenesis, mitochondrial respiration and the mitochondrial membrane potential during adipogenic differentiation of human MSCs. In addition, we inhibited mitochondrial function to assess its effects on adipogenic differentiation. Our data show that mitochondrial biogenesis and oxygen consumption increase markedly during adipogenic differentiation, and that reducing mitochondrial respiration by hypoxia or by inhibition of the mitochondrial electron transport chain significantly suppresses adipogenic differentiation. Furthermore, we used a novel approach to suppress mitochondrial activity using a specific siRNA-based knockdown of the mitochondrial transcription factor A (TFAM), which also resulted in an inhibition of adipogenic differentiation. Taken together, our data demonstrates that increased mitochondrial activity is a prerequisite for MSC differentiation into adipocytes. These findings suggest that metabolic modulation of adult stem cells can maintain stem cell pluripotency or direct adult stem cell differentiation.</p></div

Mitochondrial redox status changes with hMSCs adipogenic differentiation.

<p><b>A)</b> Undifferentiated and 7 day adipogenic differentiated MSCs were transfected with a redox-sensitive GFP construct (roGFP) targeted to the mitochondria. By using different excitation wavelengths (400 and 490 nm) and measuring emission at 535 nm, the redox status of cells was assessed (a higher 400/490 ratio corresponds to a more oxidized mitochondrial matrix). Ratios are represented in the form of a heat map, with reduced mitochondria shown in blue and oxidized mitochondria in red. <b>B)</b> Quantification of the roGFP data. Mitochondrial redox state is reduced after adipogenic differentiation. As a positive control, cells were also treated with 100 µM H₂O₂ to induce a completely oxidized state. <b>C)</b> Immunoblotting indicates that catalase and mitochondrial superoxide dismutase (SOD2) protein levels increased during differentiation, while cytoplasmic superoxide dismutase (SOD1) levels were not significantly affected by differentiation (n = 3 for each group).</p

TFAM knockdown inhibits adipogenic differentiation of hMSCs.

<p><b>A)</b> Immunofluorescent staining for TFAM, the key regulator of mitochondrial transcription, showed that TFAM is upregulated in hMSCs undergoing adipogenic differentiation. <b>B)</b> High dose siTFAM can significantly lower TFAM expression levels (n = 4 for each group). <b>C)</b> Knockdown of TFAM inhibits the differentiation process as confirmed by lower adiponectin mRNA levels (n = 4 for each group). <b>D)</b> Lowering TFAM results in lower expression of the mitochondrial gene MtND2, while the nuclear gene cytochrome C (CytC) is not affected, confirming the specificity of siRNA treatment (n = 3 for each group).</p

Mitochondrial membrane potential changed with hMSC adipogenic differentiation.

<p><b>A)</b> JC-1 staining was used for the measurement of mitochondrial membrane potential. The ratio of red/green (and thus polarization) decreased with adipogenic differentiation. Note that not all cells were fully differentiated even after 21 days. Asterisks highlight the smaller, undifferentiated cells, while the arrow points at a larger and well-differentiated cell that contains multiple lipid droplets. Upon differentiation, mitochondrial depolarization (green color) was clearly present. <b>B)</b> Real-time RT-PCR data showed increased expression of PGC-1α and of the 3 uncoupling proteins (UCP1, 2, 3) following adipogenic differentiation (n = 5 for each group).</p

Mitochondrial biogenesis increased with adipogenic differentiation of hMSCs.

<p><b>A)</b> Adipogenic differentiation was associated with a marked increase in mitochondrial mass, as demonstrated by increased MitoTracker Green staining. <b>B)</b> Flow cytometry measurement of MitoTracker Green staining confirmed the increase of mitochondrial mass as the mean fluorescence intensity is doubled after 7 days of adipogenic differentiation (n = 3 for each group). <b>C)</b> The protein levels of the mitochondrial outer membrane protein TOM20, a reliable marker of mitochondrial mass, showed a marked increase after adipogenic differentiation.</p