Journal of nutrition & intermediary metabolism最新文献

Aim

Current dietary assessment methods are prone to subjective bias, highlighting the demand for an objective marker of fruit and vegetable (F/V) intake. Carotenoids from F/V consumption deposit in skin and adipose tissue, contributing to changes in skin colour. Results from research in females have highlighted positive associations between skin colour assessed by reflectance spectroscopy and F/V intake. The aim of this study was to determine the relationship between (i) F/V intake, (ii) carotenoid intake and skin colour in young Caucasian men.

Methods

In this cross-sectional study reflectance spectroscopy was used to quantify skin colour in young Caucasian men. Skin colour was assessed at eight sun-exposed and unexposed body locations. A food frequency questionnaire was administered to assess F/V intake over the past month. Partial correlations were done to assess the associations between skin yellowness, F/V intake (grams) and carotenoid intake (milligrams), both with and without controlling for skin lightness.

Results

Carotenoid intake was strongly associated with F/V intake (r = 0.8, p < 0.001). Skin yellowness was found to be strongly associated with both carotenoid (r = 0.599, p < 0.001) and F/V (r = 0.422, p = 0.02) intake. When skin colour was controlled for skin lightness and measured at the forehead, biceps, palm and foot sole, a stronger association was observed (carotenoid (r = 0.637, p < 0.001); F/V (r = 0.431, p = 0.02)).

Conclusion

Skin colour is a viable biomarker of F/V intake in young Caucasian men. These findings contribute to the development of an objective marker of F/V intake, however more research is required before the method can be applied to practice.

Background

Repeated exposure to elevated postprandial triglycerides, as seen with typical Western diets, contributes to atherosclerosis and vascular disease. We determined if a single serving of non-fat milk added to a high fat tolerance test could attenuate postprandial hypertriglyceridemia in individuals who consume a high fat diet.

Methods

In this placebo-controlled, randomized, crossover experimental study, 30 overweight/obese adults consumed a high-fat tolerance test meal combined with either non-fat milk, carbohydrate control drink, or caloric control drink.

Results

Plasma triglycerides increased over time with no significant differences between interventions. Peak plasma triglyceride levels during HFTT were significantly related to dietary fat intake (r = 0.30, p < 0.05). When participants were divided into tertiles based on habitual dietary fat intake, the higher fat diet group exhibited reduced triglyceride net integrated area under the curve when supplemented with non-fat milk. No significant differences in hemodynamic measures (brachial flow-mediated dilation and femoral vascular conductance) were observed between the milk and caloric control trials for either the low fat or high fat diet groups.

Conclusions

A single serving of non-fat milk may attenuate acute hypertriglyceridemia in individuals who chronically consume a high fat diet, offering a simple and easily implemented option for managing elevations in postprandial triglycerides.

Metformin is the only biguanide derivative used to treat type 2 diabetes mellitus (T2D). Several studies documented that its use contributes to vitamin B12 deficiency in 10–30% of diabetics. The incidence of deficiency varies among populations and studies reported. There has been no reports documenting this incidence in the Middle East and Lebanon.

The objectives of this study were to establish the incidence of vitamin B12 in our population, to investigate and characterize any specific associations between taking metformin and vitamin B12 deficiency to establish clear recommendations based on this data.

During the first 6 months of 2015, we conducted a cross sectional study on 200 Lebanese individuals. The cohort consisted of subjects with an established diagnosis of T2D and who have been on metformin for at least three months. The patients were subjected to a questionnaire, medical record review, and vitamin B12 level measurement.

Thirty three percent of the subjects were found to have borderline values of the serum vitamin B12 (148–220 pg/dl) while 22.5% had a clear, deficiency (levels less than 148 pg/dl). We found a highly significant inverse correlation between the dose and duration of metformin treatment and the serum levels of vitamin B12. Furthermore, both borderline and low levels of vitamin B12 were associated with the presence of different neuropathies and macrocytic anemia in a dose dependent manner.

Based on our results, we strongly recommend the routine screening of subjects with T2D on metformin for vitamin B12 deficiency due to its high prevalence and the significant clinical effects it may result in. Furthermore, we recommend, based on our data, to start treating those subjects once a borderline or low level is detected.

Dietary consumption of polyphenol-rich fruits, such as grapes, may reduce inflammation and potentially prevent diseases linked to inflammation. Here, we used a genetically engineered murine model to measure Nuclear Factor kappa-light-chain-enhancer of activated B cells (NF-κB) activity and pro-inflammatory cytokine secretion to test the hypothesis that oral consumption of whole grape formulation reduces inflammatory signaling in the body. NF-κB luciferase reporter mice were divided into two groups, one which was fed an experimental diet formulated with 4% (w/w) whole grape powder (WGP) or another which was fed a control diet formulated with 3.6% glucose/fructose (w/w) combination. Simulated inflammation was induced in the mice by intraperitoneal injection of lipopolysaccharide (LPS). In vivo imaging was used to determine the effect of each diet on NF-κB activity. We found that there were no significant differences in weight gain between the WGP and control diet groups. However, there was a statistically significant (p < 0.0001) difference in the progression of basal levels of NF-κB signaling between mice fed on control or WGP diet. There were no significant differences in NF-κB reporter indices between WGP- and control-diet groups after either acute or repeated inflammatory challenge. However, terminal blood collection revealed significantly (p < 0.01) lower serum concentrations of the inflammatory cytokines Interleukin-6 (IL-6) and Tumor Necrosis Factor alpha (TNFα) only among WGP diet mice subjected to acute inflammatory challenge. Overall, these data suggest that while diets supplemented with WGP may suppress steady-state low levels of inflammatory signaling, such a supplementation may not alleviate exogenously induced massive NF-κB activation.

Metabolic diseases of significant dietary cause have been multiplying since the climax of the Industrial Revolution and are approaching pandemic proportions. Diet has been promulgated as a cornerstone in tackling these diseases. Understanding the long-term molecular modulatory functions of a diet on key metabolic pathways associated with the pathophysiology of these diseases cannot be overemphasised. Since rice is a staple food for more than half of the world's population and has been linked to some metabolic diseases, we assert that understanding the long-term molecular modulatory effect of rice cultivars on PPARγ and GLUT4 gene products could reduce the burden of these diseases. This would be done by harnessing which property of a rice cultivar alters important metabolic pathways necessary for normal body function. Forty-eight nulliparous rats fed for 90 days with differing rice cultivars were mated with male rats raised on standard pellet. The resulting pups and dams were sacrificed (n = 6). Their adipose tissue, hepatic tissue and muscle tissue were investigated for PPARγ and GLUT4 gene expression regulations. Protein was also extracted from the aforementioned tissues, separated on SDS-PAGE and blotted and probed with PPARγ and GLUT4 primary antibodies, followed by a secondary antibody. Global hepatic DNA methylation due to the interventions were quantified using a DNA methylation kit. Our findings showed that germination status and high amylose composition properties in rice cultivars prevented the downregulation of GLUT4 gene products in standard-chow- and high-fat-diet-fed rats. It also prevented the upregulation of PPAR gene products in the same rats. Alterations in mRNA and protein regulations were inherited by the offspring. Furthermore, germinated rice cultivars with high amylose content demonstrated lower hepatic DNA methylation levels compared with low-amylose white rice. Also, a 50% correlation was observed between mRNA and protein levels of the various interventions employed. In overall, the findings point towards an expected lesser burden of diet-related metabolic diseases if the beneficial properties of a high-amylose content and germination status in a rice cultivar are harnessed.

Cereals and legumes, being the major staples of many African communities, frequently used for complementary foods for infants and young children. However, aflatoxin contamination is a threatening issue in these staples and its negative effects on human health, most especially infants and young children, are very alarming. Thus, this review sought to highlight the risk of aflatoxin contamination in cereals and legumes so as to reconsider their usage in complementary feeding. Factors such as temperature, relative humidity/moisture, soil properties, type and length of storage as well as nutrient composition of the food produce greatly influence fungal growth and aflatoxin production in cereals and legumes. Consumption of such contaminated food ingredients could expose many infants and young children to poor growth and development. Nonetheless, the toxin, though seemingly inevitable, can be minimized if not curbed completely through awareness creation/education, good agricultural practices and proper storage practices. Moreover, consumption of root and tuber crops such as sweetpotato, especially the orange-fleshed sweetpotato, can be a sustainable approach to reduce aflatoxin ingestion in children. Thus, to control the adverse effects of aflatoxin in infants and young children, cereal-legume blends could be substituted with root and tuber-based blends in complementary feeding.

The prevalence of obesity and associated ailments have shown tremendous rise in recent times and drew the attention of researchers to explore effective therapeutic alternatives. In the present study, polyphenolic rich fraction of Terminalia paniculata bark (TPPF) was evaluated for its ability to inhibit adipogenesis, pancreatic lipase and amylase activity. The maximum inhibitory activity of lipase (78%) and amylase (81%) was noticed at 250 μg/mL of TPPF. During cytotoxicity assay with MTT, TPPF did not show any cytotoxic effect on 3T3-L1 cells up to a concentration of 400 μg/mL. Oil Red O staining of 3T3-L1 cells showed considerable reduction in adipocytes differentiation and lipid accumulation in the presence of TPPF (250 μg/mL) when compared with untreated 3T3-L1 cells. HPLC analysis of TPPF revealed the presence of Gallic acid, Ellagic acid and Quercetin as the major components. Our results suggest that, TPPF may be useful in attenuating obesity ailments.

Snacking (eating between meals) is a common behaviour, which is often blamed for poor diets because snack foods can be high in sodium, fat and sugar. In addition, uncompensated calories from snacking could contribute to overweight and obesity. However, the evidence is inconclusive, and to some extent this could be explained by the lack of a universal definition as to what counts as a snack. The present study looks at snack foods as defined by USDA in the LanguaL Thesaurus, and evaluated their nutritional quality using the Nutrient Balance Concept. It also explored whether these USDA-defined snacks could be incorporated into a healthy menu plan (US MyPlate). The results of this study showed that only about a sixth are high in nutrients considered as potentially harmful for human health when consumed in high amounts. By contrast almost three-quarters of these snack foods are poor in nutrients that are considered essential (or very important) for human health. However, overall diet quality, assessed using the Nutrient Balance Concept, was compromised only by those snack foods that are especially high in sodium and/or saturated fatty acids.

A number of preclinical and clinical studies have suggested that omega-3 fatty acids have a prophylactic effect against depression. The aim of this study was to explore the effect of eicosapentaenoic acid (EPA) on development of depression among Japanese patients with hyperlipidemia. This was a 3-year follow up study based on medical claims data obtained from Japan Medical Data Center. A total of 76,561 patients were eligible for the final analyses. The exposure group included EPA drug users categorized into 2 groups based on adherence to EPA using the Medication Possession Ratio (MPR) with a cutoff of 80%. The control group (non-EPA group) consisted of subjects taking lipid-lowering medications other than EPA. A Cox proportional hazard model was used to evaluate the association between EPA drug use and the development of depression. Over 3 year-follow up, 1319 (1.7%) patients developed depression. In the multivariate Cox proportional hazard model, no association was found between depression and EPA drug use in the MPR ≥80% group (HR:0.89, 95%CI: 0.67 to 1.20) or MPR < 80% group (HR:1.00, 95%CI: 0.73 to 1.37) compared with the non-EPA group. No convincing evidence was found to support the association between EPA and risk of depression before and after adjusting for age, gender, and comorbidity.