Daniela Graf

Contribution of diet to the composition of the human gut microbiota.

In the human gut, millions of bacteria contribute to the microbiota, whose composition is specific for every individual. Although we are just at the very beginning of understanding the microbiota concept, we already know that the composition of the microbiota has a profound impact on human health. A key factor in determining gut microbiota composition is diet. Preliminary evidence suggests that dietary patterns are associated with distinct combinations of bacteria in the intestine, also called enterotypes. Western diets result in significantly different microbiota compositions than traditional diets. It is currently unknown which food constituents specifically promote growth and functionality of beneficial bacteria in the intestine. The aim of this review is to summarize the recently published evidence from human in vivo studies on the gut microbiota-modulating effects of diet. It includes sections on dietary patterns (e.g. Western diet), whole foods, food constituents, as wells as food-associated microbes and their influence on the composition of human gut microbiota. The conclusions highlight the problems faced by scientists in this fast-developing field of research, and the need for high-quality, large-scale human dietary intervention studies.

Anthocyanin-Rich Juice Lowers Serum Cholesterol, Leptin, and Resistin and Improves Plasma Fatty Acid Composition in Fischer Rats

Obesity and obesity-associated diseases e.g. cardiovascular diseases and type 2 diabetes are spread worldwide. Anthocyanins are supposed to have health-promoting properties, although convincing evidence is lacking. The aim of the present study was to investigate the effect of anthocyanins on several risk factors for obesity-associated diseases. Therefore, Fischer rats were fed anthocyanin-rich grape-bilberry juice or an anthocyanin-depleted control juice for 10 weeks. Intervention with anthocyanin-rich grape-bilberry juice reduced serum cholesterol and tended to decrease serum triglycerides. No effects were seen for serum non-esterified fatty acids, glucose, and insulin. Anthocyanin-rich grape-bilberry juice intervention reduced serum leptin and resistin, but showed no influence on serum adiponectin and secretion of adipokines from mesenteric adipose tissue. Furthermore, anthocyanin-rich grape-bilberry juice increased the proportion of polyunsaturated fatty acids and decreased the amount of saturated fatty acids in plasma. These results indicate that anthocyanins possess a preventive potential for obesity-associated diseases.

Anthocyanin‐rich juice does not affect gut‐associated immunity in Fischer rats

SCOPE Most studies on immunomodulatory effects of anthocyanins are concentrated on their anti-inflammatory potential. In vitro studies suggest that anthocyanins possess anti-inflammatory potential, but results from in vivo studies are rare and inconclusive. Sparse information is available about the immune tissues that are affected by anthocyanins. As systemic bioavailability of anthocyanins is rather low, predominantly luminal anthocyanins could influence the gut-associated lymphoid tissue (GALT). Therefore, the present study investigated the immunomodulatory effects of an anthocyanin-rich grape-bilberry juice (ARJ) on the systemic immune system, GALT, and mesenteric adipose tissue (MAT). METHODS AND RESULTS Fischer rats (n = 24/group) received ARJ or anthocyanin-depleted grape-bilberry juice (control) for 10 wk. Lymphocytes were isolated from blood, spleen, Peyers Patches, and mesenteric lymph nodes. Anthocyanin intake was 15 mg/day and concentrations were determined in plasma and intestinal tract. Number of T and natural killer cells, natural killer cell activity, cytokine secretion from lymphocytes (IL-10, IFN-γ, and TNF-α) and MAT (IL-6, IL-10, and MCP-1), inflammation markers in serum (sICAM, IFN-γ, and MCP-1), and activation status of NF-κB were not influenced by ARJ. CONCLUSION This in vivo study suggests that anthocyanins at physiological doses affect neither the systemic immune system, nor GALT, or MAT in healthy, unchallenged rats.

Isoflavone supplementation in postmenopausal women does not affect leukocyte LDL receptor and scavenger receptor CD36 expression: A double‐blind, randomized, placebo‐controlled trial

SCOPE Isoflavones are discussed to improve serum lipoproteins and body composition and to reduce cardiovascular disease risk in postmenopausal women (PMW). LDL receptors (LDLR) and scavenger receptor CD36 (CD36) play a pivotal role in the regulation of plasma LDL-cholesterol concentrations (LDL-chol). We investigated the impact of isoflavones on the receptor expression of both receptors in leukocytes of PMW. METHODS AND RESULTS A randomized, double-blind, placebo-controlled trial in parallel design was conducted to assess the effects of an isoflavone-enriched soy extract (117.4 mg/day isoflavone aglycone equivalents) for 12 weeks on serum LDL-chol, LDLR, and CD36 expression on leukocytes in 170 healthy PMW. Baseline and after 12 weeks, blood lipid concentrations, anthropometric data and body composition were determined. Receptor expression on leukocytes was measured by means of flow cytometry. After the intervention, no significant differences were found for LDLR and CD36 expression on leukocytes. A significant increase of serum LDL-chol was shown for the isoflavone group (p = 0.03) after 12 weeks. Body fat content and VAT were not affected. CONCLUSION Isoflavone supplementation for 12 weeks did not change LDLR and CD36 expression on leukocytes of PMW and did not affect body fat content and visceral adipose tissue (VAT), but slightly increased serum LDL-chol.

Anthocyanin-rich grape-bilberry juice influences fat metabolism and improves risk factors for cardiovascular diseases in fischer rats: 20th International Congress of Nutrition: Granada, Spain, September 15–20, 2013, Abstracts

Abstract of paper that presented at 20th International Congress of Nutrition, Granada, September 2013.Background and Objectives: Indonesia is one of the countries facing nutrition transition with an increased proportion of the middle-class population. Few studies explored young child feeding practice amongst middle class families in developing countries. This study aims to assess child feeding practices and their associations with child nutritional status in urban area of Indonesia. Methods: The study was designed as a mixed-method study in an urban middle-class community, comprising of a qualitative study amongst 26 families of young children and a case-control study involving 288 (109 cases and 179 controls) children aged 12-36 months. Cases were mild to moderately underweight children, while controls were normal weight children. The data collection methods consisted of in-depth interview for the qualitative phase and anthropometry measurements, structured interviews pertaining to child feeding practices and 24-hours recall for the quantitative phase. Results: The qualitative study suggested that mothers appeared to have positive attitude and were familiar with many brands of toddler formula milk. Mothers reported challenges in encouraging their children to eat and relied on formula milk to increase child’s food intake.The results of the case-control study showed that only 10.4% children received six-month exclusive breastfeeding and there was a significantly higher proportion of control than case children who were offered formula milk within their first month of life. Almost all children (91.7%, CI = 87.7 – 94.5) had low dietary diversity (consumed 1-3 food groups) in the last 24 hours. Formula milk was the largest contributor to child’s energy intake amongst the control children. Conclusions: The low dietary diversity warn potential problems for the health of Indonesian children. A large government strategy on complementary feeding practices including controlling the marketing activities of formula milk need to be enhanced.