Glycemic index and microstructure analysis of a newly developed fiber enriched cookie

A diet with a high glycemic index (GI) is associated with an elevated risk for obesity or type 2 diabetes. We investigated the GI of a newly-developed fiber enriched cookie and characterized the microstructure of ingredients used. In a study with 26 non-diabetic healthy volunteers it was shown that the fiber enriched cookie has a GI of 58.9 in relation to white bread as reference. Using a conversion factor of 1.4, the GI of the fiber enriched cookie in relation to a glucose-solution is 42.0 and can be classified as a low-GI food. Postprandial insulin concentration was significantly lower after consumption of fiber enriched cookies compared to white bread. Glucose release after in vitro digestion was significantly lower from fiber enriched cookies compared to other cookies tested. In addition to its high percentage of fiber, the cookies’ low GI can be attributed to the limited gelatinization potential of the starch granules found in the ingredients used. Using confocal laser scanning microscopy it is shown that starch granule surface area of whole grain barley flour, spelt flour and oat flakes bears cluster-shaped protein–NSPS complexes that preferentially absorb water in conditions of water shortage and thereby prevent starch gelatinization

Effects of a 12-week high-α-linolenic acid intervention on EPA and DHA concentrations in red blood cells and plasma oxylipin pattern in subjects with a low EPA and DHA status

The essential omega-3 fatty acid alpha-linolenic acid (ALA, 18:3n3) can be converted into EPA and DHA. The aim of the present study was to determine the effect of a high-ALA diet on EPA and DHA levels in red blood cells (RBCs) and their oxylipins in the plasma of subjects with a low EPA and DHA status. Fatty acid concentrations [μg mL−1] and relative amounts [% of total fatty acids] in the RBCs of 19 healthy men (mean age 26.4 ± 4.6 years) were analyzed by means of GC-FID. Free plasma oxylipin concentrations were determined by LC-MS based targeted metabolomics. Samples were collected and analyzed at baseline (week 0) and after 1 (week 1), 3 (week 3), 6 (week 6), and 12 (week 12) weeks of high dietary ALA intake (14.0 ± 0.45 g day−1). ALA concentrations significantly (p < 0.001) increased from 1.44 ± 0.10 (week 0) to 4.65 ± 0.22 (week 1), 5.47 ± 0.23 (week 3), 6.25 ± 0.24 (week 6), and 5.80 ± 0.28 (week 12) μg mL−1. EPA concentrations increased from 6.13 ± 0.51 (week 0) to 7.33 ± 0.33 (week 1), 8.38 ± 0.42 (p = 0.021, week 3), 10.9 ± 0.67 (p < 0.001, week 6), and 11.0 ± 0.64 (p < 0.001, week 12) μg mL−1. DHA concentrations unexpectedly decreased from 41.0 ± 1.93 (week 0) to 37.0 ± 1.32 (week 1), 36.1 ± 1.37 (week 3), 35.1 ± 1.06 (p = 0.010, week 6), and 30.4 ± 1.09 (p < 0.001, week 12) μg mL−1. Relative ΣEPA + DHA amounts were unchanged during the intervention (week 0: 4.63 ± 0.19, week 1: 4.67 ± 0.16, week 3: 4.61 ± 0.13, week 6: 4.73 ± 0.15, week 12: 4.52 ± 0.11). ALA- and EPA-derived hydroxy- and dihydroxy-PUFA increased similarly to their PUFA precursors, although in the case of ALA-derived oxylipins, the concentrations increased less rapidly and to a lesser extent compared to the concentrations of their precursor FA. LA-derived oxylipins remained unchanged and arachidonic acid and DHA oxylipin concentrations were not significantly changed. Our results confirm that the intake of ALA is not a sufficient source for the increase of EPA + DHA in subjects on a Western diet. Specifically, a high-ALA diet results in increased EPA and declined DHA concentrations. However, the changes effectively balance each other out so that ΣEPA + DHA in RBCs – which is an established marker for health protective effects of omega-3-PUFA – remains constant. The PUFA levels in RBCs reflect the concentration and its changes in plasma hydroxy- and dihydroxy-PUFA concentrations for ALA and EPA

Systematic functional analysis of rab GTPases reveals limits of neuronal robustness to environmental challenges in flies

Rab GTPases are molecular switches that regulate membrane trafficking in all cells. Neurons have particular demands on membrane trafficking and express numerous Rab GTPases of unknown function. Here, we report the generation and characterization of molecularly defined null mutants for all 26 rab genes in Drosophila. In flies, all rab genes are expressed in the nervous system where at least half exhibit particularly high levels compared to other tissues. Surprisingly, loss of any of these 13 nervous system-enriched Rabs yielded viable and fertile flies without obvious morphological defects. However, all 13 mutants differentially affected development when challenged with different temperatures, or neuronal function when challenged with continuous stimulation. We identified a synaptic maintenance defect following continuous stimulation for six mutants, including an autophagy-independent role of rab26. The complete mutant collection generated in this study provides a basis for further comprehensive studies of Rab GTPases during development and function in vivo

The transcription factor TAL1 and miR-17-92 create a regulatory loop in hematopoiesis

A network of gene regulatory factors such as transcription factors and microRNAs establish and maintain gene expression patterns during hematopoiesis. In this network, transcription factors regulate each other and are involved in regulatory loops with microRNAs. The microRNA cluster miR-17-92 is located within the MIR17HG gene and encodes six mature microRNAs. It is important for hematopoietic differentiation and plays a central role in malignant disease. However, the transcription factors downstream of miR-17-92 are largely elusive and the transcriptional regulation of miR-17-92 is not fully understood. Here we show that miR-17-92 forms a regulatory loop with the transcription factor TAL1. The miR-17-92 cluster inhibits expression of TAL1 and indirectly leads to decreased stability of the TAL1 transcriptional complex. We found that TAL1 and its heterodimerization partner E47 regulate miR-17-92 transcriptionally. Furthermore, miR-17-92 negatively influences erythroid differentiation, a process that depends on gene activation by the TAL1 complex. Our data give example of how transcription factor activity is fine-tuned during normal hematopoiesis. We postulate that disturbance of the regulatory loop between TAL1 and the miR-17-92 cluster could be an important step in cancer development and progression.Deutsche ForschungsgemeinschaftProjekt DEA

Effects of Opuntiaficus-indica flower extract WS 1261 on mental and psychic function in subsyndromal fatigue - A pilot study

Traditional use, chemical constituents, and results of prior animal studies indicate alleviating effects of Opuntiaficus-indica flowers extract on subsyndromalfatigue symptoms in humans 50 healthy subjects of either gender aged 30 to 60 years with subsyndromal fatigue were enrolled in this open-label monocentric single arm proof-of-principle study. 500mg of a hydro-alcoholic extract from Opuntiaficus-indica flowers were administered daily over 8 weeks. Mental and psychic function parameters were assessed by numerical analogue scale of Subjective Fatigue Symptoms, Multidimensional Fatigue Inventory 20, Sheehan Disability Scale, Short Form Health Survey 36, Fatigue Impact Scale, and Global Self-Assessment. Also, health-related incidents, laboratory parameters and vital signs were measured during the intervention period. Improvement of fatigue symptoms could be shown in most measurements after week 1and continued further throughout the trial. 70.0% of subjects reported global improvement of their complaints at end of study. A consistent and positive effect of Opuntiaficus-indica flowers extract on symptoms of fatigue could be demonstrated. Improvement in all mental and psychic functions could be measured, most of them statistically significant

Effects of Opuntia ficus-indica flower extract WS 1261 on mental and psychic function in subsyndromal fatigue – A pilot study

Background Traditional use, chemical constituents, and results of prior animal studies indicate alleviating effects of Opuntia ficus-indica flowers extract on subsyndromal fatigue symptoms in humans Methods 50 healthy subjects of either gender aged 30 to 60 years with subsyndromal fatigue were enrolled in this open-label monocentric single arm proof-of-principle study. 500mg of a hydro-alcoholic extract from Opuntia ficus-indica flowers were administered daily over 8 weeks. Mental and psychic function parameters were assessed by numerical analogue scale of Subjective Fatigue Symptoms, Multidimensional Fatigue Inventory 20, Sheehan Disability Scale, Short Form Health Survey 36, Fatigue Impact Scale, and Global Self-Assessment. Also, health-related incidents, laboratory parameters and vital signs were measured during the intervention period. Results Improvement of fatigue symptoms could be shown in most measurements after week 1 and continued further throughout the trial. 70.0% of subjects reported global improvement of their complaints at end of study. Conclusions A consistent and positive effect of Opuntia ficus-indica flowers extract on symptoms of fatigue could be demonstrated. Improvement in all mental and psychic functions could be measured, most of them statistically significant

Effects of a low and a high dietary LA/ALA ratio on long-chain PUFA concentrations in red blood cells

There is a debate about the optimal dietary ratio of the parent n6 fatty acid linoleic acid (LA) and n3 fatty acid alpha-linolenic acid (ALA) to promote an efficient conversion of ALA to EPA and DHA, which have implications for human health. The aim of the present study was to compare the effects of a low-LA/high-ALA (loLA/hiALA) diet with a high-LA/low-ALA (hiLA/loALA) diet on fatty acid concentrations in red blood cells (RBCs). Fifteen omnivore healthy men (mean age 26.1 ± 4.5 years) with a low initial EPA/DHA status (sum (∑) EPA + DHA% of total fatty acids in RBC at baseline: 4.03 ± 0.17) received both diets for two weeks with a nine-week wash-out phase in between. Fatty acid intake of the subjects was tightly controlled. Concentrations [μg mL−1] and relative amounts [% of total fatty acids] of fatty acids in RBCs were analyzed at baseline (day 0), day 7 and 14 by means of GC-FID. The dietary LA/ALA ratios were 0.56 ± 0.27 : 1 and 25.6 ± 2.41 : 1 and led to significantly different changes of ALA, LA, EPA and ∑EPA + DHA concentrations in RBCs. In the course of the loLA/hiALA diet ALA and EPA concentrations and relative amounts of ∑EPA + DHA increased, whereas LA concentrations decreased. The DHA concentration was unaffected. The hiLA/loALA diet led to slightly decreased EPA concentrations, while all other fatty acid concentrations remained constant. Compared to our previous study, where we simply increased the ALA intake, our results show that ALA supplementation combined with a reduced LA intake (loLA/hiALA diet) more efficiently enhanced EPA blood concentrations. The absence of changes in the PUFA pattern in consequence of a LA/ALA ratio of 25.6 ± 2.41 : 1 suggests that the high LA/ALA ratio of the Western diet already leads to a saturation and a further increase of the ratio does not affect the PUFA pattern