Plasticity of Mouse Brain Docosahexaenoic Acid: Modulation by Diet and Age

Decreases in brain docosahexaenoic acid (DHA) have been associated with losses in brain function leading to an interest in the conditions which lead to such brain decreases, and such variables as age. Also of relevance would be the rate of repletion of DHA when the n-3 dietary deficiency is reversed. This experiment describes dietary deficiency in n-3 fatty acids induced in weanling (3 week) and young adult (7 week) mice. There was an immediate and continuous loss of brain DHA with similar rates in the two age groups. Serum DHA declined more rapidly in younger animals with respect to similarly treated adults. Brain and serum docosapentaenoic acid (DPAn-6) increased more rapidly and to higher levels in the younger animals. A second experiment determined the rates of normalization of brain fatty acid profiles when alpha-linolenic acid was added to the diets of n-3 deficient mice. Brain DHA recovery occurred at a faster rate (half-time, T _1/2 = 1.4 weeks) when begun at weaning relative to young adult mice (T _1/2 = 3.5 weeks). Correspondingly, brain DPAn-6 recovered faster in the younger animals; the adult group had a half-time of more than twice that of the 3-week old group. This study therefore demonstrates that the young adult mouse brain DHA is somewhat plastic and can be partially depleted via a low n-3 fatty acid diet and subsequently restored when dietary n-3 fatty acids are repleted. Relevance of these findings for human nutrition is discussed.     

High Saturated Fat Diet Alters the Lipid Composition of Triacylglycerol and Polar Lipids in the Femur of Dam and Offspring Rats

Previous work has shown that dietary lipids alter femur lipid composition. Specifically, we have shown that exposure to high saturated fatty acid (SFA) diets in utero, during suckling, or post‐weaning alters femur total lipid composition, resulting in higher percent bone mass in males and females and bone mineral density (BMD) in female offspring with no effect on bone mineral outcomes in dams. Comparatively, high n‐3 polyunsaturated fatty acid (PUFA) diets increase femur polar (PL) lipid n‐3 content, which has been associated with increased bone mineral content and strength. However, the extent that PL or triacylglycerol (TAG) lipids change with high SFA diets is unknown. The current investigation examined the influence of a high SFA diet (20 % lard by weight) on femur PL and TAG lipid composition in 5‐month old female Wistar rats (fed high SFA diet from age 28 days onwards; dams) and their 19‐day old offspring (exposed to high SFA in utero and during suckling; pups). High SFA exposure resulted in increased monounsaturates and decreased n‐3 and n‐6 PUFA in the TAG fraction in both dams and pups, and higher SFA and n‐6:n‐3 ratio in dams only. The PL fraction showed decreased n‐6 PUFA in both dams and pups. The magnitude of the diet‐mediated responses, specifically TAG 18:1 and PL n‐6 PUFA, may have contributed to the previously reported altered BMD, which was supported with correlation analysis. Future research should investigate the relationship of diet‐induced changes in bone lipids on bone structure, as quantified through micro‐computed tomography.     

Assessment of in vivo bioaccessibility of arsenic in dietary rice by a mass balance approach

A pilot dietary experiment was conducted over 10 days to evaluate whether a simple yet often underutilized approach of constructing mass balance of arsenic metabolites can be used to assess in vivo bioaccessibility of arsenic in cooked rice. Two volunteers were involved in this study. The quantity of drinking water, food and urine samples, together with arsenic concentration and speciation of these samples was monitored to construct a mass balance of arsenic intake and excretion. In the first five days, the two volunteers on a wheat diet had an average arsenic daily intake of 15.4 ± 2.6 µg and 9.6 ± 0.7 µg, respectively. In the next five days, these volunteers switched to a rice diet, increasing the average arsenic daily intake to 36.4 ± 2.8 µg and 34.1 ± 7.7 µg, respectively. Daily excretion of urinary arsenic, mostly as dimethylarsenic acid (DMA), doubled from 9.8 ± 0.3 µg to 21.0 ± 3.0 µg, and from 6.5 ± 0.8 µg to 11.6 ± 4.5 µg, respectively. The percentage of ingested arsenic excreted in urine remained constant at ∼ 58% for one volunteer before and after the rice diet, and was ∼ 69% for another. Mass balance established during a controlled dietary experiment over 10 days is shown to be a useful approach to evaluate in vivo bioaccessibility and metabolism of arsenic uptake from diet and is applicable to study with more subjects.     

Dietary Protein's and Dietary Acid Load's Influence on Bone Health

A variety of genetic, mechano-response-related, endocrine-metabolic, and nutritional determinants impact bone health. Among the nutritional influences, protein intake and dietary acid load are two of the factors most controversially discussed. Although in the past high protein intake was often assumed to exert a primarily detrimental impact on bone mass and skeletal health, the majority of recent studies indicates the opposite and suggests a bone-anabolic influence. Studies examining the influence of alkalizing diets or alkalizing supplement provision on skeletal outcomes are less consistent, which raises doubts about the role of acid–base status in bone health. The present review critically evaluates relevant key issues such as acid–base terminology, influencing factors of intestinal calcium absorption, calcium balance, the endocrine-metabolic milieu related to metabolic acidosis, and some methodological aspects of dietary exposure and bone outcome examinations. It becomes apparent that for an adequate identification and characterization of either dietary acid load's or protein's impact on bone, the combined assessment of both nutritional influences is necessary.     

Epigenetic effects of natural polyphenols: A focus on SIRT1‐mediated mechanisms

Polyphenols are a class of natural compounds widely distributed in fruits, vegetables, and plants. They have been reported to possess a wide range of activities in prevention and alleviation of various diseases like cancer, neuroinflammation, diabetes, and aging. Polyphenols are effective against chronic diseases and recent reports indicated strong epigenetic effects of polyphenols. Most of the studies investigating epigenetic effects of natural polyphenols have focused on their beneficial effects in cancer treatment. However, epigenetic defects have been demonstrated in many other diseases as well, and application of polyphenols to modulate the epigenome is becoming an interesting field of research. This review summarizes the effects of natural polyphenols in modulating epigenetic‐related enzymes as well as their effect in prevention and treatment of chronic diseases with a focus on SIRT1 modulation. We have also discussed the relation between the structure and function of epigenetic‐modifying polyphenols.     

The acceptability of the New Nordic Diet by participants in a controlled six-month dietary intervention

A healthy and palatable ‘New Nordic Diet’ (NND) has been designed with the aim to improve public health in Denmark. In order to explore barriers and possibilities for acceptance of the NND by the wider population this study analyzes acceptance of the NND and a control diet labeled the ‘Average Danish Diet’ (ADD) among participants in a randomized controlled intervention study of the two diets’ health effects. Based on questionnaires presented before (N = 197) and after (N = 147) the intervention, an eating acceptance index expressing eating qualities and a practical acceptance index expressing practical implications of the diet in everyday life were developed. Variations in practical and eating acceptance in relation to key background variables were explored.The NND had high eating acceptance and low practical acceptance when measured after the intervention. The ADD had low eating acceptance but high practical acceptance. NND participants already exhibiting healthy eating habits before the intervention showed the highest eating acceptance of the NND. The ADD had the highest eating acceptance among ADD participants exhibiting less healthy eating habits before the intervention. In spite of high eating acceptance, low practical acceptance may hinder broader public acceptance of the New Nordic Diet.     

Dietary supplementation evening primrose oil improve symptoms of fibromyalgia syndrome

Evening primrose oil (EPO) is widely used as a dietary supplement from which beneficial effects have been reported in rheumatic and arthritic conditions, atopic dermatitis, premenstrual and menopausal syndrome, and atopic dermatitis. This study was designed to examine the effect of diets supplemented with EPO on generalized chronic pain, including fibromyalgia syndrome, induced by intermittent cold stress (ICS) in mice. After completing the in vivo test, we proceeded to isolation and culture of peritoneal macrophages in order to determine the effects on the inflammatory status. The results indicate that dietary-EPO is suitable to improve mechanical and thermal allodynia and hyperalgesia and it is also being able to improve behavioural disturbances, anxiety and depression. Besides, EPO reduced significantly the proinflammatory mediators as ON, PGE₂, TXB₂ and IL-1β in LPS-macrophages stimulated from EPO fed animals. In conclusion, this study demonstrates that dietary-EPO can modify the nociceptive response and other symptoms associated with fibromyalgia syndrome, as well as to reduce the release of the inflammatory state.