1,862 research outputs found
Is there a role for carbohydrate restriction in the treatment and prevention of cancer?
Over the last years, evidence has accumulated suggesting that by systematically reducing the amount of dietary carbohydrates (CHOs) one could suppress, or at least delay, the emergence of cancer, and that proliferation of already existing tumor cells could be slowed down. This hypothesis is supported by the association between modern chronic diseases like the metabolic syndrome and the risk of developing or dying from cancer. CHOs or glucose, to which more complex carbohydrates are ultimately digested, can have direct and indirect effects on tumor cell proliferation: first, contrary to normal cells, most malignant cells depend on steady glucose availability in the blood for their energy and biomass generating demands and are not able to metabolize significant amounts of fatty acids or ketone bodies due to mitochondrial dysfunction. Second, high insulin and insulin-like growth factor (IGF)-1 levels resulting from chronic ingestion of CHO-rich Western diet meals, can directly promote tumor cell proliferation via the insulin/IGF1 signaling pathway. Third, ketone bodies that are elevated when insulin and blood glucose levels are low, have been found to negatively affect proliferation of different malignant cells in vitro or not to be usable by tumor cells for metabolic demands, and a multitude of mouse models have shown anti-tumorigenic properties of very low CHO ketogenic diets. In addition, many cancer patients exhibit an altered glucose metabolism characterized by insulin resistance and may profit from an increased protein and fat intake
Recommended from our members
Proceedings of the 2nd annual symposium of the German Society for Paleo Nutrition held in 2014
We present the scientific abstracts of the 2nd Annual Symposium of the German Society for Paleo Nutrition (Deutsche Gesellschaft für Paläoernährung e.V.) which was held on November 8th 2014 in Schweinfurt, Germany. The topics presented had a great variety that included (i) a discussion of specific foods (one talk addressed the potential problems associated with cow’s milk consumption and one talk dealt with the staple foods of the Hadzda hunter-gatherers); (ii) the emerging role of ketogenic diets in the treatment of neurodegenerative diseases and cancer; (iii) an overview of intermittend fasting and its effects on health and performance; (iv) an extension of evolutionary principles beyond nutrition and their incorporation into everyday life in a way we term the paleo concept
Proceedings of the 1st annual symposium of the German Society for Paleo Nutrition held in 2013
Evolutionary Medicine is an emerging medical field that mainly addresses the causes of diseases under the consideration of evolutionary principles [1]. Viewing diseases through the evolutionary perspective also opens up new and innovative treatment strategies. In particular, the understanding that most of the so-called “diseases of civilization” emerge from a discrepancy between our modern, civilized lifestyle and that towards which our human species (as hunters and gatherers) has evolved, challenges the concept of these diseases being chronic and provides new treatment approaches. Examples of such approaches were provided in the first annual symposium of the recently founded German Society for Paleo Nutrition (Deutsche Gesellschaft für Paläoernährung e.V., DGPE). The meeting entitled ”Modern Lifestyle – Modern Diseases” took place on October 5th 2013 in Schweinfurt, Germany, and focussed specifically on nutrition in health and disease from an evolutionary perspective. This paper is a collection of abstracts of the scientific talks given at the sympoisum
Proceedings of the 3rd annual symposium of the German Society for Paleo Nutrition held in 2015
We present the scientific abstracts of the 3rd Annual Symposium of the German Society for Paleo Nutrition (Deutsche Gesellschaft für Paläoernährung e.V.) which was held on July 26th 2015 in Berlin, Germany. The focus of this year's symposium was on the future challenges of human society including topics such as nutritional sustainability, the paleo-deficit syndrome or frailty of the elderly due to body composition change
Halo streams in the solar neighborhood
The phase-space structure of our Galaxy holds the key to understand and
reconstruct its formation. The Lambda-CDM model predicts a richly structured
phase-space distribution of dark matter and (halo) stars, consisting of streams
of particles torn from their progenitors during the process of hierarchical
merging. While such streams quickly loose their spatial coherence in the
process of phase mixing, the individual stars keep their common origin
imprinted into their kinematic and chemical properties, allowing the recovery
of the Galaxy's individual "building blocks". The field of Galactic Archeology
has witnessed a dramatic boost over the last decade, thanks to the increasing
quality and size of available data sets. This is especially true for the solar
neighborhood, a volume of 1-2 kpc around the sun, where large scale surveys
like SDSS/SEGUE continue to reveal the full 6D phase-space information of
thousands of halo stars. In this review, I summarize the discoveries of stellar
halo streams made so far and give a theoretical overview over the search
strategies imployed. This paper is intended as an introduction to researchers
new to field, but also as a reference illustrating the achievements made so
far. I conclude that disentangling the individual fragments from which the
Milky Way was built requires more precise data that will ultimately be
delivered by the Gaia mission.Comment: 26 pages, 6 figures, 1 table; accepted for publication in The
Astronomy and Astrophysics Revie
The visitor from an ancient galaxy: A planetary companion around an old, metal-poor red horizontal branch star
We report the detection of a planetary companion around HIP 13044, a
metal-poor red horizontal branch star belonging to a stellar halo stream that
results from the disruption of an ancient Milky Way satellite galaxy. The
detection is based on radial velocity observations with FEROS at the 2.2-m
MPG/ESO telescope. The periodic radial velocity variation of P=16.2 days can be
distinguished from the periods of the stellar activity indicators. We computed
a minimum planetary mass of 1.25 Jupiter masses and an orbital semimajor axis
of 0.116 AU for the planet. This discovery is unique in three aspects: First,
it is the first planet detection around a star with a metallicity much lower
than few percent of the solar value; second, the planet host star resides in a
stellar evolutionary stage that is still unexplored in the exoplanet surveys;
third, the planetary system HIP 13044 most likely has an extragalactic origin
in a disrupted former satellite of the Milky Way.Comment: 5 pages, 2 figures, 2 tables, submitted to the Proceedings of the
276th IAU Symposium "The Astrophysics of Planetary Systems
Effects of publication bias on conservation planning
Conservation planning needs reliable information on spatial patterns of
biodiversity. However, existing data sets are skewed: some habitats, taxa, and
locations are under-represented. Here, we map geographic publication density at
the sub-national scale of individual 'provinces'. We query the Web of Science
catalogues SCI and SSCI for biodiversity-related publications including country
and province names (for the period 1993-2016). We combine these data with other
provincial-scale factors hypothesised to affect research (i.e. economic
development, human presence, infrastructure and remoteness). We show that sites
that appear to be understudied, compared with the biodiversity expected from
their bioclimatic conditions, are likely to have been inaccessible to
researchers for a diversity of reasons amongst which current or recent armed
conflicts are notable. Finally, we create a priority list of provinces where
geographic publication bias is of most concern, and discuss how our
provincial-scale model can assist in adjusting for publication biases in
conservation planning.Comment: 10 pages; 3 figures; 1 table;R code on
https://github.com/raffael-hickisch; data at
https://zenodo.org/record/998889; interactive at
http://bit.ly/publication_density_ma
Sexual Differentiation of Circadian Clock Function in the Adrenal Gland
Sex differences in glucocorticoid production are associated with increased responsiveness of the adrenal gland in females. However, the adrenal-intrinsic mechanisms that establish sexual dimorphic function remain ill defined. Glucocorticoid production is gated at the molecular level by the circadian clock, which may contribute to sexual dimorphic adrenal function. Here we examine sex differences in the adrenal gland using an optical reporter of circadian clock function. Adrenal glands were cultured from male and female Period2::Luciferase (PER2::LUC) mice to assess clock function in vitro in real time. We confirm that there is a pronounced sex difference in the intrinsic capacity to sustain PER2::LUC rhythms in vitro, with higher amplitude rhythms in adrenal glands collected from males than from females. Changes in adrenal PER2::LUC rhythms over the reproductive life span implicate T as an important factor in driving sex differences in adrenal clock function. By directly manipulating hormone levels in adult mice in vivo, we demonstrate that T increases the amplitude of PER2::LUC rhythms in adrenal glands of both male and female mice. In contrast, we find little evidence that ovarian hormones modify adrenal clock function. Lastly, we find that T in vitro can increase the amplitude of PER2::LUC rhythms in male adrenals but not female adrenals, which suggests the existence of sex differences in the mechanisms of T action in vivo. Collectively these results reveal that activational effects of T alter circadian timekeeping in the adrenal gland, which may have implications for sex differences in stress reactivity and stress-related disorders
- …