Boronate probes for the detection of hydrogen peroxide release from human spermatozoa

Human spermatozoa are compromised by production of reactive oxygen species (ROS) and detection of ROS in spermatozoa is important for the diagnosis of male infertility. Probes 2',7'-dichlorohydrofluorescein diacetate (DCFH), dihydroethidium (DHE) and MitoSOX red (MSR) are commonly used for detecting ROS by flow cytometry, however these probes lack sensitivity to hydrogen peroxide (H2O2), which is particularly damaging to mammalian sperm cells. This study reports the synthesis and use of three aryl boronate probes, peroxyfluor-1 (PF1), carboxy peroxyfluor-1 (CPF1) and a novel probe 2(2-ethoxyethoxy)ethoxy peroxyfluor-1 (EEPF1) in human spermatozoa. PF1 and EEPF1 were found to be effective in detecting H2O2 and peroxynitrite (ONOO(-)) produced by spermatozoa when stimulated with menadione or 4-hydroxynonenal. EEPF1 was more effective at detection of ROS in spermatozoa than DCFH, DHE and MSR; furthermore it distinguished poorly motile sperm as shown by greater ROS production. EEPF1 should therefore have a significant role in diagnosis of oxidative stress in male infertility, cryopreservation, age, lifestyle and exposure to environmental toxicants.Malcolm S. Purdey, Haley S. Connaughton, Sara Whiting, Erik P. Schartner, Tanya M. Monro, Jeremy G. Thompson, R. John Aitken, Andrew D. Abel

The Effect of a Brief Salivary α-Amylase Exposure During Chewing on Subsequent in Vitro Starch Digestion Curve Profiles

There is inconsistency between current in vitro digestion methods with regard to accommodation of a (salivary) α-amylase exposure during the oral phase. The effect of a salivary α-amylase pre-exposure on subsequent in vitro starch digestion curve profiles for various foods was investigated. Foods were chewed, expectorated and the boluses left to rest for 0–15 min. During pancreatic digestion, aliquots were taken and hydrolysis curves constructed for comparison against those of the same foods comminuted with a manually-operated chopper, hence spared exposure to saliva. Hydrolysate aliquots taken at T0 (time zero) of the digestion of chewed samples contained higher levels of glucose and dextrins compared with chopped samples. Pancreatin activity immediately overwhelmed differences in sugar released due to salivary amylase activity. Within 10 min no differences were detectable between hydrolysis curves for chewed and chopped foods. Salivary amylase pretreatment does not contribute to the robustness or relative accuracy of in vitro methods

Protocol for a randomized controlled study of Iyengar yoga for youth with irritable bowel syndrome

<p>Abstract</p> <p>Introduction</p> <p>Irritable bowel syndrome affects as many as 14% of high school-aged students. Symptoms include discomfort in the abdomen, along with diarrhea and/or constipation and other gastroenterological symptoms that can significantly impact quality of life and daily functioning. Emotional stress appears to exacerbate irritable bowel syndrome symptoms suggesting that mind-body interventions reducing arousal may prove beneficial. For many sufferers, symptoms can be traced to childhood and adolescence, making the early manifestation of irritable bowel syndrome important to understand. The current study will focus on young people aged 14-26 years with irritable bowel syndrome. The study will test the potential benefits of Iyengar yoga on clinical symptoms, psychospiritual functioning and visceral sensitivity. Yoga is thought to bring physical, psychological and spiritual benefits to practitioners and has been associated with reduced stress and pain. Through its focus on restoration and use of props, Iyengar yoga is especially designed to decrease arousal and promote psychospiritual resources in physically compromised individuals. An extensive and standardized teacher-training program support Iyengar yoga's reliability and safety. It is hypothesized that yoga will be feasible with less than 20% attrition; and the yoga group will demonstrate significantly improved outcomes compared to controls, with physiological and psychospiritual mechanisms contributing to improvements.</p> <p>Methods/Design</p> <p>Sixty irritable bowel syndrome patients aged 14-26 will be randomly assigned to a standardized 6-week twice weekly Iyengar yoga group-based program or a wait-list usual care control group. The groups will be compared on the primary clinical outcomes of irritable bowel syndrome symptoms, quality of life and global improvement at post-treatment and 2-month follow-up. Secondary outcomes will include visceral pain sensitivity assessed with a standardized laboratory task (water load task), functional disability and psychospiritual variables including catastrophizing, self-efficacy, mood, acceptance and mindfulness. Mechanisms of action involved in the proposed beneficial effects of yoga upon clinical outcomes will be explored, and include the mediating effects of visceral sensitivity, increased psychospiritual resources, regulated autonomic nervous system responses and regulated hormonal stress response assessed via salivary cortisol.</p> <p>Trial registration</p> <p>ClinicalTrials.gov <a href="http://www.clinicaltrials.gov/ct2/show/NCT01107977">NCT01107977</a>.</p

Level of agreement between objectively determined body composition and perceived body image in 6- To 8-year-old South African children- To Body Composition-Isotope Technique study

To assess the level of agreement between body size self-perception and actual body size determined by body mass index (BMI) z-score and body fatness measured by the deuterium dilution method (DDM) in South African children aged 6-8 years. A cross-sectional sample of 202 children (83 boys and 119 girls) aged 6-8 years from the Body Composition-Isotope Technique study (BC-IT) was taken. Subjective measures of body image (silhouettes) were compared with the objective measures of BMI z-score and body fatness measured by the DDM. The World Health Organization BMI z-scores were used to classify the children as underweight, normal, overweight, or obese. DDM-measured fatness was classified based on the McCarthy centile curves set at 2nd, 85th and 95th in conjunction with fatness cut-off points of 25% in boys and 30% in girls. Data were analyzed using SPSS v26. Of 202 children, 32.2%, 55.1%, 8.8%, and 2.4% perceived their body size as underweight, normal, overweight, and obese, respectively. Based on BMI z-score, 18.8%, 72.8%, 6.9%, and 1.5% were classified as underweight, normal, overweight, and obese, respectively. Body fatness measurement showed that 2.5%, 48.0%, 21.8%, and 29.7% were underweight, normal weight, overweight, and obese, respectively

Faecal bulking efficacy of Australasian breakfast cereals

Faecal bulk may play an important role in preventing a range of disorders of the large bowel, but as yet there is little information available on the relative faecal bulking capacities of various foods. Breakfast cereals are often promoted as a good source of potential bulk for &apos;inner health&apos; because they provide dietary fibre, but their relative abilities to provide faecal bulk per se have not been described. The faecal bulking efficacy of 28 representative Australasian breakfast cereals was therefore measured. A rat model developed for the purpose, and shown to give similar responses as humans to cereal fibres, was used to measure faecal bulking efficacy as increases in fully hydrated faecal weight/100 g diet, based on precise measurements of food intake, faecal dry matter output and faecal water-holding capacity (g water held without stress/g faecal dry matter). Compared to a baseline diet containing 50% sucrose, increments in hydrated faecal weight due to 50% breakfast cereal ranged from slightly negative (Cornflakes, -2 g/100 g diet) to about 80 g/100 g diet (San Bran). Most breakfast cereals increased hydrated faecal weight by between 10 and 20 g/100 g diet from a baseline of 21 ± 1.5 g/100 g diet, but four products containing high levels of wheat bran had an exceptionally large impact on hydrated faecal weight (increment &gt;20 g/100 g diet), and the changes resulted more from relative changes in dry matter output than in faecal water retention/gram. However, as faecal water retention was about 2.5 g water/g faecal dry matter on average, increases in dry matter represented large increases in faecal water load. Faecal bulking indices (FBI) for most of the breakfast cereals were less than 20 (wheat bran = 100). The content of wheat bran equivalents for faecal bulk (WBE fb) ) in the breakfast cereals was calculated from FBI. Most breakfast cereals contributed, per serve, less than 10% of a theoretical daily reference value for faecal bulk (DRV fb = 63 WBE fb /day), which was based on data from human clinical trials and dietary fibre recommendations. Based on the WBE fb contribution/serving that would be required to meet the DRV fb from the number of servings of dietary fibre sources in the CSIRO 12345+ food and nutrition plan, the results suggest that although some high bran breakfast cereals may contribute substantially to, and many are reasonable sources of, faecal bulk, for most of them, one or two servings at breakfast cannot be relied on to effectively redress shortfalls in faecal bulk elsewhere in the diet

Gut microbiota responses to dietary fibre sources in rats fed starch-based or quasi-human background diets

The effects of whole foods and food components on gut microbiota are often investigated in animal models not fed a human-type background diet. In this study, rats were fed basal starch (BS) or quasi human (QH) background diets either unsubstituted (controls) or substituted with inulin, dried kiwifruit or pectin for 28 days. Gut microbiota composition and hydrated faecal bulking potential of the diets were evaluated. In the caecum and colon, relative abundance of bacteria at the phylum, family or genus levels differed considerably between the background diets (BS and QH). Rats fed QH diets had higher Actinobacteria than those rats fed BS diets. Gut microbiota responses to inulin, kiwifruit and pectin depended on the background diet. QH diet led to twice the mass of hydrated faecal bulk than BS diet. Overall, simple laboratory animal diets are unlikely to provide valid predictions of effects of prebiotics added to human diets

Effects of potato fiber and potato-resistant starch on biomarkers of colonic health in rats fed diets containing red meat

Nyanhanda, T ORCiD: 0000-0001-6502-5645The effects of red meat consumption with and without fermentable carbohydrates on indices of large bowel health in rats were examined. Sprague-Dawley rats were fed cellulose, potato fiber, or potato-resistant starch diets containing 12% casein for 2 wk, then similar diets containing 25% cooked beef for 6 wk. After week 8, cecal and colonic microbiota composition, fermentation end-products, colon structure, and colonocyte DNA damage were analyzed. Rats fed potato fiber had lower Bacteroides-Prevotella-Porphyromonas group compared to other diet groups. Colonic Bifidobacterium spp. and/or Lactobacillus spp. were higher in potato fiber and potato-resistant starch diets than in the cellulose diet. Beneficial changes were observed in short-chain fatty acid concentrations (acetic, butyric, and propionic acids) in rats fed potato fiber compared with rats fed cellulose. Phenol and p-cresol concentrations were lower in the cecum and colon of rats fed potato fiber. An increase in goblet cells per crypt and longer crypts were found in the colon of rats fed potato fiber and potato-resistant starch diets. Fermentable carbohydrates had no effect on colonic DNA damage. Dietary combinations of red meat with potato fiber or potato-resistant starch have distinctive effects in the large bowel. Future studies are essential to examine the efficacy of different types of nondigestible carbohydrates in maintaining colonic health during long-term consumption of high-protein diets. Practical Application: Improved understanding of interactions between the food consumed and gut microbiota provides knowledge needed to make healthier food choices for large bowel health. The impact of red meat on large bowel health may be ameliorated by consuming with fermentable dietary fiber, a colonic energy source that produces less harmful by-products than the microbial breakdown of colonic protein for energy. Developing functional red meat products with fermentable dietary fiber could be one way to promote a healthy and balanced macronutrient diet. © 2012 Institute of Food Technologists®