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Objective: To investigate the association between physical activity accumulated from early (age 22–27 y) to mid (age 40–45 y) adulthood and resting heart rate at age 41–46 years in women. Methods: Data were from 479 participants in the 1973–1978 cohort of the Australian Longitudinal Study on Women's Health. Participants reported physical activity every 3 years from age 22–27 years to 40–45 years. Linear regression models were used to investigate the associations of a cumulative physical activity score (average physical activity across 18 y; up to 7 surveys) and changes in physical activity from age 22–33 years to 34–45 years with resting heart rate at age 41–46 years. Results: Average resting heart rate at age 41–46 years was 75 (SD: 11) beats per minute. An inverse nonlinear dose–response association between cumulative physical activity and resting heart rate was observed. Overall, accumulation of physical activity was associated with lower resting heart rate regardless of the age when physical activity was accumulated. Women in the highest tertile of physical activity at both age 22–33 years and 34–45 years had a resting heart rate, on average, 8 beats per minute lower (95% confidence interval, −11.42 to −4.69) than those consistently in the lowest tertile of physical activity. Conclusion: Accumulating physical activity, irrespective of timing, appears to provide cardiovascular health benefits for women before the transition to menopause. [ABSTRACT FROM AUTHOR]

Background and Aims Physical inactivity, sedentary behaviour (SB), and inadequate sleep are key behavioural risk factors of cardiometabolic diseases. Each behaviour is mainly considered in isolation, despite clear behavioural and biological interdependencies. The aim of this study was to investigate associations of five-part movement compositions with adiposity and cardiometabolic biomarkers. Methods Cross-sectional data from six studies (n = 15 253 participants; five countries) from the Prospective Physical Activity, Sitting and Sleep consortium were analysed. Device-measured time spent in sleep, SB, standing, light-intensity physical activity (LIPA), and moderate-vigorous physical activity (MVPA) made up the composition. Outcomes included body mass index (BMI), waist circumference, HDL cholesterol, total:HDL cholesterol ratio, triglycerides, and glycated haemoglobin (HbA1c). Compositional linear regression examined associations between compositions and outcomes, including modelling time reallocation between behaviours. Results The average daily composition of the sample (age: 53.7 ± 9.7 years; 54.7% female) was 7.7 h sleeping, 10.4 h sedentary, 3.1 h standing, 1.5 h LIPA, and 1.3 h MVPA. A greater MVPA proportion and smaller SB proportion were associated with better outcomes. Reallocating time from SB, standing, LIPA, or sleep into MVPA resulted in better scores across all outcomes. For example, replacing 30 min of SB, sleep, standing, or LIPA with MVPA was associated with −0.63 (95% confidence interval −0.48, −0.79), −0.43 (−0.25, −0.59), −0.40 (−0.25, −0.56), and −0.15 (0.05, −0.34) kg/m2 lower BMI, respectively. Greater relative standing time was beneficial, whereas sleep had a detrimental association when replacing LIPA/MVPA and positive association when replacing SB. The minimal displacement of any behaviour into MVPA for improved cardiometabolic health ranged from 3.8 (HbA1c) to 12.7 (triglycerides) min/day. Conclusions Compositional data analyses revealed a distinct hierarchy of behaviours. Moderate-vigorous physical activity demonstrated the strongest, most time-efficient protective associations with cardiometabolic outcomes. Theoretical benefits from reallocating SB into sleep, standing, or LIPA required substantial changes in daily activity. [ABSTRACT FROM AUTHOR]

Cardiac hypertrophy is characterized by stimulation of hypertrophic signalling pathways representing the reactivation of the ‘foetal gene program’ (hypertrophic genes) and activation of the MAPK pathway. Angiotensin II (AngII) stimulates cardiac hypertrophy, a process which may involve the transactivation of epidermal growth factor receptors (ErbBs). Three subtypes of ErbBs are present in the postnatal heart (ErbB1, 2, 4), yet their precise roles are poorly understood. We have shown that the ErbB4-selective ligand neuregulin 1 beta-1 (NRG1-β1) potently stimulates cardiomyocyte hypertrophy. We now aim to determine if AngII activates hypertrophic signalling in cardiomyocytes by transactivation of ErbBs, particularly ErbB4.Ventricular cardiomyocytes from neonatal rats were treated with AngII (100 nM) or NRG1-β1 (10 nM) to induce hypertrophic signalling. ErbB1, 2, 4 were downregulated using shRNA and siRNA. Reporter assays were used to measure promoter activity of the hypertrophic genes myosin light chain 2v (MLC-2V), atrial natriuretic peptide (ANP) and cyclin D. ERK1/2 activation was measured via Western blot.NRG caused robust activation of the hypertrophic gene MLC-2V (11.3 fold increase versus untreated control) that was significantly reduced to 4.3-fold by silencing of ErbB4 (n = 5, P < 0.01), but not ErbB1 or ErbB2, confirming that ErbB4 activation contributes to hypertrophic signalling. However, knockdown of ErbB1, 2 or 4 did not affect AngII-induced activation of MLC-2V (5.8 fold increase versus untreated control). Similar results were seen for ANP and cyclin D. Similarly, ErbB4 knockdown reduced NRG1-β1-induced MAPK activation from 21.0-fold to 13.5 fold (n=4, p<0.05), whilst Ang II-induced MAPK activation was unaffected.Cardiomyocyte hypertrophy can be promoted by activation of AT1 and ErbB4 receptors. AngII-induced hypertrophic signalling (measured by promoter activity of MLC-2V, ANP and cyclin D and MAPK activation) may not involve transactivation of ErbB receptors. We are now extending these findings in vivo; we have established a model of cardiac-specific ErbB4 deletion using Cre/Lox recombination, and are undertaking echocardiographic analysis to measure cardiac hypertrophy and function. [ABSTRACT FROM AUTHOR]

Objective: To determine the effect of lipopolysaccharide (LPS) on NF-κB gene expression and proinflammatory cytokine release from trophoblast cell models, JEG-3 and BeWo human choriocarcinoma cells., Study Design: Serum-starved JEG-3 and BeWo cells were treated with LPS (from Escherichia coli serotype 0111:B4) for 24 or 48h. Cell culture medium was collected and assayed for interleukin (IL)-1β, IL-6, IL-8, and transforming necrosis factor (TNF)-α cytokine release using enzyme-linked immunosorbent assays. RNA was extracted from the cells and real-time PCR was performed to measure NF-κB mRNA expression. All results were analyzed by one-way analysis of variance tests followed by Sidak's post hoc analysis. p<0.05 was considered statistically significant., Results: LPS triggered an inflammatory response in JEG-3 cells by inducing a 1.5-fold increase in NF-κB mRNA expression and TNF-α release (0μg/mL: 15.13±2.14, 1μg/mL: 14.94±0.75, 10μg/mL: 23.05±4.50, p<0.05) and a 2-fold elevation in IL-6 secretion (0μg/mL: 12.54±5.44, 1μg/mL: 25.54±0.91, 10μg/mL: 24.28±4.43, p<0.05). In contrast, BeWo cells were not as sensitive to LPS exposure; NF-κB mRNA expression was unchanged between LPS-treated and control cells, whereas a small but significant 1.3-fold increase in TNF-α release was found (TNF-α: 15.45±1.53pg/mL, control: 12.24±1.00pg/mL, p<0.05). The inflammatory pathways in BeWo cells were found to be active given that treatment of these cells with IL-1β and TNF-α induced IL-6 secretion. Interestingly, 1μg/mL LPS appeared to decrease IL-6 and TNF-α release from BeWo cells. IL-1β and IL-8 secretion were not detected from either cell lines., Conclusion: LPS activates the NF-κB pathway in JEG-3 but not BeWo human choriocarcinoma cells and this may be the reason for their differential inflammatory response to LPS exposure., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

The high fat content in Western diets probably affects placental function during pregnancy with potential consequences for the offspring in the short and long term. The aim of the present study was to compare genome-wide placental gene expression between rat dams fed a high-fat diet (HFD) and those fed a control diet for 3 weeks before conception and during gestation. Gene expression was measured by microarray and pathway analysis was performed. Gene expression differences were replicated by real-time PCR and protein expression was assessed by Western blot analysis. Placental and fetal weights at E17.25 were not altered by exposure to the maternal HFD. Gene pathways targeting placental growth, blood supply and chemokine signalling were up-regulated in the placentae of dams fed the HFD. The up-regulation in messenger RNA expression for five genes Ptgs2 (fatty acid cyclo-oxidase 2; COX2), Limk1 (LIM domain kinase 1), Pla2g2a (phospholipase A2), Itga1 (integrin α-1) and Serpine1 was confirmed by real-time PCR. Placental protein expression for COX2 and LIMK was also increased in HFD-fed dams. In conclusion, maternal HFD feeding alters placental gene expression patterns of placental growth and blood supply and specifically increases the expression of genes involved in arachidonic acid and PG metabolism. These changes indicate a placental response to the altered maternal metabolic environment.