206 research outputs found
Administration of the antioxidant n-acetyl-cysteine in pregnant mice has long-term positive effects on metabolic and behavioral endpoints of male and female offspring prenatally exposed to a high-fat diet
A growing body of evidence suggests the consumption of high-fat diet (HFD) during pregnancy to model maternal obesity and the associated increase in oxidative stress (OS), might act as powerful prenatal stressors, leading to adult stress-related metabolic or behavioral disorders. We hypothesized that administration of antioxidants throughout gestation might counteract the negative effects of prenatal exposure to metabolic challenges (maternal HFD feeding during pregnancy) on the developing fetus. In this study, female C57BL/6J mice were fed HFD for 13 weeks (from 5-weeks of age until delivery) and were exposed to the N-acetyl-cysteine (NAC) antioxidant from 10-weeks of age until right before delivery. Body weight of the offspring was assessed following birth, up to weaning and at adulthood. The metabolic, neuroendocrine and emotional profile of the adult offspring was tested at 3-months of age. Prenatal HFD increased motherâs body weight and offspringâs weight at the time of weaning, when administered in conjunction with NAC. In females, NAC administration reduced high levels of leptin resulting from prenatal HFD. Prenatal NAC administration also resulted in greater glucose tolerance and insulin sensitivity while increasing adiponectin levels, as well as increasing exploratory behavior, an effect accompanied by reduced plasma corticosterone levels in response to restraint stress. Analysis of glutathione levels in the hypothalamus and in brown adipose tissue indicates that, while HFD administration to pregnant dams led to reduced levels of glutathione in the offspring, as in the male hypothalamus, NAC was able to revert this effect and to increase glutathione levels both in the periphery (Brown Adipose Tissue, both males and females) and in the central nervous system (males). Overall, results from this study indicate that the body redox milieu should be tightly regulated during fetal life and that buffering OS during pregnancy can have important long-term consequences on metabolic and behavioral endpoints
Sex-Specific Effects of Prenatal Stress on Bdnf Expression in Response to an Acute Challenge in Rats : a Role for Gadd45β
Exposure to early adversities represents a major risk factor for psychiatric disorders. We have previously shown that exposure to prenatal stress (PNS) in rats alters the developmental expression of brain-derived neurotrophic factor (Bdnf) with a specific temporal profile. However, exposure to early-life stress is known to alter the ability to cope with challenging events later in life, which may contribute to the enhanced vulnerability to stress-related disorders. Since Bdnf is also an important player for activity-dependent plasticity, we investigated whether the exposure to PNS in rats could alter Bdnf responsiveness to an acute challenge at adulthood. We found that exposure to PNS produces significant changes in Bdnf responsiveness with brain region- and gender-specific selectivity. Indeed, exposure to an acute stress upregulates Bdnf expression in the prefrontal cortex, but not in the hippocampus, of control animals. Moreover, such modulatory activity is selectively impaired in PNS female rats, an effect that was associated with changes in the modulation of the DNA demethylase Gadd45\u3b2. Our results suggest that exposure to PNS may reprogram gene transcription through epigenetic mechanisms reducing the ability to cope under adverse conditions, a trait that is disrupted in psychiatric diseases
Acoustic Signatures of Habitat Types in the Miombo Woodlands of Western Tanzania
The Miombo Woodlands of Tanzania comprise several habitat types that are home to a great number of flora and fauna. Understanding their responses to increasing human disturbance is important for conservation, especially in places where people depend so directly on their local ecosystem services to survive. Soundscapes are a powerful approach to study complex biomes undergoing change. The sounds emitted by soniferous fauna characterize the acoustic profile of the landscapes they inhabit such that habitats with the highest acoustic abundance are considered as the most diverse and possibly more ecologically resilient. However, acoustic variability within similar habitat types may pose a challenge not only in determining their pristine condition but also in acoustically detecting their ecological change. The study presented here attempts to assess the soundscapes across habitat types in the Miombo Woodlands of the Issa Valley, Tanzania. A set of 24-hour audio recordings was collected using passive acoustic recorders over an area of 18000 km2. Sites were clustered based on acoustic indices that quantified sound diversity, and this cluster was compared to a similar cluster based on habitat physical attributes calculated using MODIS imagery and geographic information systems. The culminating analysis is a statistical correlation between habitats as defined by their soundscapes and by their landscape attributes. Results indicate acoustic variability was greater in dense canopy habitats and that wetland soundscapes are strongly correlated to the landscape attributes. More analysis need to be done to detect further ecological factors affecting the soundscape in places where the variability was high
Trehalose administration in C57BL/6N old mice affects healthspan improving motor learning and brain anti-oxidant defences in a sex-dependent fashion: a pilot study
Aim of this study was to characterize the effects of oral trehalose administration (2%w/v) on healthspan in old mice. Trehalose was administered in drinking water for 1 month to male and female C57BL/6N mice aged 25-months. After behavioral phenotyping (grip strength, beam walking and rotarod tests), autophagy (LC3-II/actin) and oxidative stress were tested in the cerebral cortex and gastrocnemius muscle. The latter parameter was indirectly assessed by evaluating carbonyl groups added to proteins as a result of oxidative reactions, in addition to central levels of NRF2 protein, a transcription factor that regulates the expression of antioxidant enzymes. In comparison with sex-matched controls, trehalose-treated males performed better in motor planning and coordination tasks. This behavioral phenotype was associated with an activation of the ubiquitin-proteasome system, autophagy and antioxidant defences in cerebral cortex. Independently from trehalose administration, females were characterized by better motor performance and showed higher levels of ubiquitinated proteins and NRF2 in cerebral cortex, suggesting an up-regulation of basal antioxidant defences. In conclusion, trehalose was effective in counteracting some aspects of age-related decay, with specific effects in male and female subjects
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Maximizing nutrition in key food value chains of Mongolia under climate change
Mongoliaâs projected warming is far above the global average and could exceed 5 âŠC by the end of the century. The reliance on pastoral livestock and rainfed agriculture along with its fragile ecosystems put Mongoliaâs economy at risk of adverse climate change impacts, particularly from climate extreme events. Eighty percent of Mongoliaâs agricultural sector is concentrated in animal husbandry with around one third of the population relying on this livelihood. Beyond livestock, food production is concentrated in few crops: wheat; potatoes; and three vegetables (cabbage, carrot, and turnip). Climate change does not only affect food production but can exacerbate malnutrition by removing food and nutrients in all stages of the food value chain. To identify perceived effects of climate change and measures to reduce climate change impacts in Mongoliaâsâs key food value chains, we implemented focus group discussions with 214 livestock and vegetable producers, traders, and food consumers. We also conducted 30 key informant interviews at the soum, provincial, and national levels across four agroecosystems in three provinces. Based on this community engagement analysis, we identify in terventions that the government and private sector, including herders and farmers, should undertake to increase the food security and nutrition of the countryâs prioritized food value chains under climate change
Trend in potassium intake and Na/K ratio in the Italian adult population between the 2008 and 2018 CUORE project surveys
Background and aims: Low potassium intake, in addition to high sodium, has been associated with higher risk of hypertension and CVD. The Study assessed habitual potassium intake and sodium/potassium ratio of the Italian adult population from 2008 to 2012 to 2018â2019 based on 24-h urine collection, in the framework of the CUORE Project/MINISAL-GIRCSI/MENO SALE PIUâ SALUTE national surveys. Methods and results: Data were from cross-sectional surveys of randomly selected age-and-sex stratified samples of resident persons aged 35â74 years in 10 (out of 20) Italian regions. Urinary electrolyte and creatinine measurements were performed in a central laboratory. Analyses considered 942 men and 916 women, examined in 2008â2012, and 967 men and 1010 women, examined in 2018â2019. In 2008â2012, the age-standardized mean of potassium intake (urinary potassium accounts for 70% of potassium intake) was 3147 mg (95% CI 3086â3208) in men and 2784 mg (2727â2841) in women, whereas in 2018â2019, it was 3043 mg (2968â3118) and 2561 mg (2508â2614) respectively. In 2008â2012, age-adjusted prevalence of persons with an adequate potassium intake (i.e. â„ 3510 mg/day) was 31% (95% CI 28â34%) for men and 18% (16â21%) for women; in 2018â2019, it was 26% (23â29%) and 12% (10â14%) respectively. The sodium/potassium ratio significantly decreased both in men and women. Conclusions: The average daily potassium intake of the Italian general adult population remains lower than the WHO and EFSA recommended level. These results suggest the need of a revision to strengthen initiatives for the promotion of an adequate potassium intake at the population level
Trend of salt intake measured by 24-h urine collection in the Italian adult population between the 2008 and 2018 CUORE project surveys
Background and aims: The WHO Global Action Plan for the Prevention of non-communicable diseases (NCDs) recommends a 30% relative reduction in mean population salt/sodium intake. The study assessed the trend in the habitual salt intake of the Italian adult population from 2008 to 2012 to 2018â2019 based on 24-h urinary sodium excretion, in the framework of the CUORE Project/MINISAL-GIRCSI/MENO SALE PIUâ SALUTE national surveys. Methods and results: Data were from cross-sectional surveys of randomly selected age and sexâstratified samples of resident persons aged 35â74 years in 10 (out of 20) Italian Regions distributed in North, Centre and South of the Country. Urinary sodium and creatinine measurements were carried out in a central laboratory. The analyses included 942 men and 916 women examined in 2008â2012, and 967 men and 1010 women examined in 2018â2019. The age-standardized mean daily population salt (sodium chloride) intake was 10.8 g (95% CI 10.5â11.1) in men and 8.3 g (8.1â8.5) in women in 2008â2012 and respectively 9.5 g (9.3â9.8) and 7.2 g (7.0â7.4) in 2018â2019. A statistically significant (p<0.0001) salt intake reduction was thus observed over 10 years for both genders, and all age, body mass index (BMI) and educational classes. Conclusions: The average daily salt intake of the Italian general adult population remains higher than the WHO recommended level, but a significant reduction of 12% in men and 13% in women has occurred in the past ten years. These results encourage the initiatives undertaken by the Italian Ministry of Health aimed at the reduction of salt intake at the population level
Long-term sex-dependent vulnerability to metabolic challenges in prenatally stressed rats
Prenatal stress (PNS) might affect the developmental programming of adult chronic diseases such as metabolic and mood disorders. The molecular mechanisms underlying such regulations may rely upon long-term changes in stress-responsive effectors such as Brain-Derived Neurotrophic Factor (BDNF) that can affect neuronal plasticity underlying mood disorders and may also play a role in metabolic regulation. Based upon previous data, we hypothesized that PNS might lead to greater vulnerability to an obesogenic challenge experienced at adulthood. In order to investigate our hypothesis, pregnant Sprague-Dawley female rats underwent a chronic procedure of restraint stress during the last week of gestation. The adult offspring were then challenged with a high fat diet (HFD) over 8 weeks and tested for metabolic and emotional endpoints. Moreover, brain specific changes in Bdnf expression levels were also assessed. Overall, HFD resulted in increased caloric intake, insulin resistance, impaired glucose tolerance and higher circulating levels of leptin, while PNS increased the leptin/adiponectin ratio, an index of metabolic risk in adult male subjects. Interestingly, HFD consumption increased anxiety-like behaviors in the Elevated Plus Maze, particularly in males, and this effect was buffered by PNS. Levels of Bdnf were finely modulated by PNS and HFD in a region- and sex-dependent fashion: female offspring overall showed greater plasticity, possibly mediated through increased total Bdnf mRNA expression both in the hippocampus and in the hypothalamus. In conclusion, while the experience of maternal stress during intrauterine life promotes metabolic dysfunction induced by a HFD at adulthood, the interaction between PNS and HFD is positive in male subjects, and in agreement with the match-mismatch hypothesis, resulting in a reduction of anxious behaviors
Retrievals of high latitude surface emissivity across the infrared from high altitude aircraft flights
We present retrievals of infrared spectral surface emissivities spanning the far and mid infrared from aircraft observations over Greenland, taken at an altitude of 9.2 km above sea level. We describe the flight campaign, available measurements and the retrieval method. The principal barriers to reducing uncertainty in the emissivity retrievals are found to be instrumental noise and our ability to simultaneously retrieve the underlying surface temperature. However, our results indicate that using the instrumentation available to us it is possible to retrieve emissivities from altitude with an uncertainty of ~ 0.02 or better across much of the infrared. They confirm that the farâinfrared emissivity of snow and ice surfaces can depart substantially from unity, reaching values as low as 0.9 between 400â450 cmâ1. They also show good consistency with retrievals from the same flight made from nearâsurface observations giving confidence in the methodology used and the results obtained for this more challenging viewing configuration. To the best of our knowledge, this is the first time that farâinfrared surface emissivity has been retrieved from altitude and demonstrates that the methodology has the potential to be extended to planned satellite farâinfrared missions
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