Acute Supplementation with Cannabidiol Does Not Attenuate Inflammation or Improve Measures of Performance following Strenuous Exercise.

Supplementation with cannabidiol (CBD) may expedite recovery when consumed after exercise. The purpose of this study was to determine if supplementation with CBD reduces inflammation and enhances performance following strenuous eccentric exercise in collegiate athletes. Twenty-four well-trained females (age = 21.2 ± 1.8 years, height = 166.4 ± 8 cm, weight = 64.9 ± 9.1 kg) completed 100 repetitions of unilateral eccentric leg extension to induce muscle damage. In this crossover design, participants were randomized to receive 5 mg/kg of CBD in pill form or a placebo 2 h prior to, immediately following, and 10 h following muscle damage. Blood was collected, and performance and fatigue were measured prior to, and 4 h, 24 h, and 48 h following the muscle damage. Approximately 28 days separated treatment administration to control for the menstrual cycle. No significant differences were observed between the treatments for inflammation, muscle damage, or subjective fatigue. Peak torque at 60°/s (p = 0.001) and peak isometric torque (p = 0.02) were significantly lower 24 h following muscle damage, but no difference in performance was observed between treatments at any timepoint. Cannabidiol supplementation was unable to reduce fatigue, limit inflammation, or restore performance in well-trained female athletes.

Consumer acceptance of watermelon flesh-rind blends and the effect of rind on refreshing perception.

Watermelon flesh is widely consumed for its appealing flavor and refreshing properties, though the rind of the fruit also has traits of interest, especially its nutritional benefits. This study aimed to determine if watermelon flesh blended with 0%, 10%, 20%, and 30% w/w rind could appeal to consumers, and the effect of rind on the refreshing perception was investigated. Consumers (n = 102) evaluated the liking and intensity levels of overall flavor, sweet, sour, green, watermelon flavor, and refreshing quality along with questions regarding the texture, off flavors, and aftertaste of the samples. The addition of rind was acceptable up to the 20% rind level, which was given an overall rating above the midpoint of the scale, while the 10% and 0% rind samples did not differ significantly (P < 0.001). Overall liking most strongly correlated with sweet liking (r = 0.78, P < 0.001) and watermelon flavor liking (r = 0.77, P < 0.001). Refreshing liking most strongly correlated with watermelon flavor liking (r = 0.75, P < 0.001) and decreased with addition of rind in the samples (P < 0.001). The excessive green notes, off flavors, and undesirable texture of rind decreased the hedonic and refreshing ratings of samples with 20% and 30% rind, respectively. This research demonstrated the acceptability of using up to 20% rind to supplement watermelon juice blends and results suggested that watermelon flavor drives the refreshing perception. PRACTICAL APPLICATION: These findings exhibit the diversity in consumer preferences for watermelon flesh blended with rind using a consumer test. The refreshing properties of watermelon flesh as related to sweetness and watermelon flavor, along with the flavor and mouthfeel attributes contributed by watermelon rind, are highlighted. Manufacturers of fruit-based beverages can apply this research to inform development of refreshing products, watermelon flavored products, or products that utilize rind waste.

Consumer acceptance of egg white partially substituted with mushrooms and mushroom-egg white flavor pairing.

Mushroom possesses a distinctive sensory quality and unique nutrients. Its pairing with egg white and consumer acceptance has never been investigated. In this study, formulated mushroom-egg white patty prototypes (white and crimini mushrooms at 0%, 10%, 20%, and 30%, either oven roasted or steamed) were evaluated by 380 participants for acceptance and intensity of nine sensory attributes. Mushroom-egg white patty prototypes received positive hedonic scores for overall acceptance and the likeability of overall flavor, mushroom flavor, meaty flavor, egg white flavor, overall texture, and firmness. Consumer overall acceptance was most strongly and positively correlated with overall flavor liking, followed by overall appearance and overall texture likeability. Additionally, the likeability of flavor pairing between mushroom and egg white was rated positively across all 16 patties, indicating a good flavor match of mushroom and egg white. Consumer hedonic levels toward mushroom patties were significantly (p ≤ .05) impacted by cooking method, mushroom type, and mushroom level. The addition of mushroom was acceptable up to 20%, with steam method and crimini mushroom most preferred. The results provided new insights into consumer attitudes and potentially important sensory factors affecting the acceptability of mushroom-egg white patties, consequently increasing the utilization and consumption of mushrooms and mushroom-blended products.

Should 'Omics' education be a part of allied health profession curricula?

Sequencing of human genome followed by monumental progress in omics sciences within last two decades has made personalized nutrition for better health is a reality for near future. The complexity of underlying science in making personalized nutrition recommendation has led to the need for training of health care providers. The International Society of Nutrigenetics/Nutrigenomics (ISNN) has mission to increase the understanding among both professionals and the general public of the role of genetic variation and nutrients in gene expression. To bring this mission to fruition, we need trained healthcare professionals ready to educate public. With this in mind, we have surveyed allied health students for their omics knowledge, desire to learn more and their perception of the need of omics education. The results show a need for training in omics in all allied health disciplines and desire of the students to learn more.

Effect of Tart Cherry Polyphenols on Osteoclast Differentiation and Activity.

Bone is maintained by an intricate balance between bone formation and bone resorption. The presence of inflammation can contribute to an imbalance in bone homeostasis by enhancing differentiation and activity of osteoclasts, the cells that participate in the breakdown of bone. Polyphenols such as flavonoids found in plant-derived foods have been shown to have anti-inflammatory effects in various tissues. Tart cherries are a rich source of such polyphenolic compounds. Using mouse macrophage cells (RAW 264.7), we examined whether tart cherry polyphenols could dose dependently inhibit the proliferation and activity of receptor activator of nuclear factor kappa-B ligand (RANKL) differentiated osteoclasts under inflammatory conditions. Tartrate-resistant acid phosphatase (TRAP) activity and staining of TRAP-positive multinucleated cells, used as indicators of osteoclast differentiation and activity, tended to decrease with tart cherry polyphenols treatment. Osteoprotegerin expression by osteoclasts was decreased in a similar manner. A significant increase in nitrite concentration was observed with the lower doses of tart cherry polyphenols of 50 and 100 µg/mL (P < .05). However, higher doses of tart cherry polyphenols (200 and 300 µg/mL) reduced nitrite concentrations below that of the control that received no tart cherry polyphenols treatment (P < .05). Western blot analyses showed that protein expression of cyclooxygenase-2 (COX-2) followed a similar trend, although results were not statistically significant. On the other hand, tart cherry polyphenols treatments dose dependently increased inducible nitric oxide synthase protein expression, with statistical significance noted at doses of 200 and 300 µg/mL. Overall, our findings suggest that the polyphenols associated with tart cherries potentially inhibit osteoclast differentiation and activity, which may be beneficial to bone health.

Advanced Glycation End Products and Risks for Chronic Diseases: Intervening Through Lifestyle Modification.

Advanced glycation end products (AGEs) are a family of compounds of diverse chemical nature that are the products of nonenzymatic reactions between reducing sugars and proteins, lipids, or nucleic acids. AGEs bind to one or more of their multiple receptors (RAGE) found on a variety of cell types and elicit an array of biologic responses. In this review, we have summarized the data on the nature of AGEs and issues associated with their measurements, their receptors, and changes in their expression under different physiologic and disease states. Last, we have used this information to prescribe lifestyle choices to modulate AGE-RAGE cycle for better health.

Anti-Inflammatory Action of Blueberry Polyphenols in HIG-82 Rabbit Synoviocytes.

Rheumatoid arthritis (RA) is an autoimmune and chronic inflammatory disease resulting in joint destruction and disability in the adult population. The etiology of RA is not well understood and presently there is no known cure for this disease. The accumulation and proliferation of fibroblast-like synoviocytes may be involved in cartilage destruction. Both in vitro and in vivo studies support an anti-inflammatory role of dietary polyphenols, the bioactive constituents found in fruits and vegetables. The objective of this study was to investigate the anti-inflammatory role of blueberry polyphenols (BBPs) using rabbit synoviocytes stimulated with tumor necrosis factor alpha (TNFα). Rabbit synoviocytes (HIG-82) were treated with varying doses of BBPs and stimulated with TNFα. Stimulation of rabbit synoviocytes with the proinflammatory cytokine TNFα increased cell proliferation by ∼19% compared with the nonstimulated control. Cell proliferation was significantly decreased in a dose-dependent manner by the treatment with BBPs. Post-TNFα stimulation, cells treated with BBPs resulted in decreases in interleukin 1 beta and nuclear factor kappa B (NFκB) concentration. Reverse transcription-polymerase chain reaction analysis showed that matrix metalloproteinase 3 increased fivefold in the control TNFα-stimulated group, but was decreased by threefold in the blueberry treatment group. These results suggest that downregulation of proinflammatory cytokines and transcription factor NFκB by naturally occurring bioactives such as BBPs may be a potential therapeutic strategy for reducing inflammation associated with RA.

Blueberries Improve Pain, Gait Performance, and Inflammation in Individuals with Symptomatic Knee Osteoarthritis.

Osteoarthritis (OA) is the most common joint disorder in the world and is the most frequent cause of walking related disability among older adults in the US, which brings a significant economic burden and reduces quality of life. The initiation and development of OA typically involves degeneration or progressive loss of the structure and function of articular cartilage. Inflammation is one of the major drives of the progression of OA. Dietary polyphenols have been studied for their anti-inflammatory properties and potential anabolic effects on the cartilage cells. Blueberries are widely consumed and are high in dietary polyphenols, therefore regular consumption of blueberries may help improve OA. The purpose of the present study was to examine the effect of freeze dried whole blueberries on pain, gait performance, and inflammation in individuals with symptomatic knee OA. In a randomized, double-blind trial, adults age 45 to 79 with symptomatic knee OA, were randomized to either consume 40 g freeze-dried blueberry powder (n = 33) or placebo powder (n = 30) daily for four months. Blood draws and assessment of pain and gait were conducted at baseline, two months, and four months. Western Ontario McMaster Osteoarthritis Index (WOMAC) questionnaires were used to assess pain and GAITRite® electronic walkway was used to evaluate gait spatiotemporal parameters. WOMAC total score and sub-groups, including pain, stiffness, and difficulty to perform daily activities decreased significantly in the blueberry treatment group (p < 0.05), but improvement of WOMAC total score and difficulty to perform daily activities were not observed in the placebo group. Normal walking pace single support percentage for both limbs increased (p = or < 0.007), while double support percentage for both limbs decreased in the blueberry treatment group (p = or < 0.003). No significant changes were observed in plasma concentrations of tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, IL-6, IL-10, IL-13, matrix metalloproteinases (MMP)-3, MMP-13, and monocyte chemoattractant protein-1 (MCP-1) in both treatment groups. However, an increasing trend for IL-13 concentration and a decreasing trend in MCP-1 concentration were noted in the blueberry group. The findings of this study suggest that daily incorporation of whole blueberries may reduce pain, stiffness, and difficulty to perform daily activities, while improving gait performance, and would therefore improve quality of life in individuals with symptomatic knee OA.

"Omics" Education in Dietetic Curricula: A Comparison between Two Institutions in the USA and Mexico.

BACKGROUND/AIMS: The completion of sequencing of the human genome and a better understanding of epigenomic regulation of gene expression have opened the possibility of personalized nutrition in the near future. This has also created an immediate need for trained personnel qualified to administer personalized nutrition education. Of all the allied healthcare personnel, dietitians are the most likely to undertake this role. However, dietitians and dietetic students are still deficient in their knowledge of nutrigenomics and other "omics" technologies. Therefore, with the eventual goal of dietetic curriculum reorganization, the International Society of Nutrigenetics/Nutrigenomics (ISNN) has set out to evaluate nutrigenomic knowledge among dietetic students from different countries. In this study, we compared nutrition and dietetic students from Texas Woman's University (TWU) and the Universidad Autónoma de Nuevo León (UANL) for their perceived need for, interest in, and knowledge of different topics within nutritional genomics. METHODS: Students from both universities were sent an e-mail link to the survey which was located at psychdata.com. One hundred twenty-seven students completed the survey. The survey assessed the students' knowledge of, perceived need for, and interest in different omics technologies, as well as their basic knowledge of basic nutrition and genetic topics. Differences were assessed using the χ2 test for homogeneity and Fisher's exact test. RESULTS: Students from TWU and UANL exhibited differences in their knowledge, desire to learn more, and perceived need for omics science in some but not all categories. CONCLUSIONS: Undergraduate nutrition students from both the USA and Mexico lack a high level of knowledge in different omics topics but recognize the role that omics will play in their future as dietitians. There were differences between the 2 universities in terms of the desire to learn more about different omics technologies and to take more classes covering different topics with nutritional genomic components. In order to make personalized nutrition a reality, future dietitians will need to become fluent in different omics technologies.

Association between serum uric acid and metabolic syndrome components in prepubertal obese children (Tanner Stage I) from Nuevo León, Mexico - a preliminary study.

BACKGROUND: Metabolic syndrome (MetS) is a major risk factor for cardiovascular disease and diabetes. Previous studies in obese children demonstrating a positive association between serum uric acid (sUA) and components of MetS are confounded by lack of uniformity in age and pubertal status of children. Therefore, we have examined the role of sUA in MetS and its components in pre-pubertal children (Tanner Stage I, age ≤ 9 years). METHODS: Pre-pubertal obese children (32 boys, 27 girls, age 6-9 years) were recruited from Nuevo Leon, Mexico. For comparison, an equal number of children with normal body mass index (BMI) in the same age range (22 Boys, 39 girls, age 6-9 years) were also recruited from the same community. Presence of MetS and its components was defined according to the criteria of International Diabetes Federation. Fasting blood was analyzed for lipids, glucose, insulin, and uric acid. RESULTS: Among the obese children, sUA was positively associated with insulin resistance and hypertriglyceridemia and negatively associated with high density lipoprotein-cholesterol (HDLc). Subjects were three times more likely to have a MetS diagnosis per one unit (md/dL) difference in sUA. Of the 59 obese pre-pubertal children, 20 were classified as having MetS defined by the presence of abdominal obesity and two or more of other components described under methods. Of these, 57.1% (20/61) had sUA between 5.1 and 7.1 mg/dl. CONCLUSIONS: The findings of this study clearly indicate a positive relationship between uric acid and MetS and its components in pre-pubertal obese children with Tanner stage I and ≤9 years of age.

Resistant starch lowers postprandial glucose and leptin in overweight adults consuming a moderate-to-high-fat diet: a randomized-controlled trial.

BACKGROUND: High-amylose maize resistant starch type 2 (HAM-RS2) stimulates gut-derived satiety peptides and reduces adiposity in animals. Human studies have not supported these findings despite improvements in glucose homeostasis and insulin sensitivity after HAM-RS2 intake which can lower adiposity-related disease risk. The primary objective of this study was to evaluate the impact of HAM-RS2 consumption on blood glucose homeostasis in overweight, healthy adults. We also examined changes in biomarkers of satiety (glucagon-like peptide-1 [GLP-1], peptide YY [PYY], and leptin) and body composition determined by anthropometrics and dual-energy x-ray absorptiometry, dietary intake, and subjective satiety measured by a visual analogue scale following HAM-RS2 consumption. METHODS: Using a randomized-controlled, parallel-arm, double-blind design, 18 overweight, healthy adults consumed either muffins enriched with 30 g HAM-RS2 (n = 11) or 0 g HAM-RS2 (control; n = 7) daily for 6 weeks. The HAM-RS2 and control muffins were similar in total calories and available carbohydrate. RESULTS: At baseline, total PYY concentrations were significantly higher 120 min following the consumption of study muffins in the HAM-RS2 group than control group (P = 0.043). Within the HAM-RS2 group, the area under the curve (AUC) glucose (P = 0.028), AUC leptin (P = 0.022), and postprandial 120-min leptin (P = 0.028) decreased independent of changes in body composition or overall energy intake at the end of 6 weeks. Fasting total PYY increased (P = 0.033) in the HAM-RS2 group, but changes in insulin or total GLP-1 were not observed. Mean overall change in subjective satiety score did not correlate with mean AUC biomarker changes suggesting the satiety peptides did not elicit a satiation response or change in overall total caloric intake. The metabolic response from HAM-RS2 occurred despite the habitual intake of a moderate-to-high-fat diet (mean range 34.5% to 39.4% of total calories). CONCLUSION: Consuming 30 g HAM-RS2 daily for 6 weeks can improve glucose homeostasis, lower leptin concentrations, and increase fasting PYY in healthy overweight adults without impacting body composition and may aid in the prevention of chronic disease. However, between-group differences in biomarkers were not observed and future research is warranted before specific recommendations can be made. TRIAL REGISTRATION: None.

Advanced Glycation End Products, Inflammation, and Chronic Metabolic Diseases: Links in a Chain?

Advanced glycation end products (AGEs) are a diverse group of compounds produced when reducing sugars react with proteins or other compounds to form glycosylated molecules. AGEs may form endogenously, and glycation of molecules may negatively affect their function. AGEs may also be consumed in food form with dietary AGEs reported to be particularly high in foods treated with high heat: baked, broiled, grilled, and fried foods. Whether dietary AGEs are absorbed in significant quantities and whether they are harmful if absorbed is a question under current debate. The American Diabetes Association makes no recommendation regarding avoidance of these foods, but many researchers are concerned that they may be pro-inflammatory and way worsen cardiac function, kidney function, diabetes and its complications and may even contribute to obesity.

Bioactive Plant Metabolites in the Management of Non-Communicable Metabolic Diseases: Looking at Opportunities beyond the Horizon.

There has been an unprecedented worldwide rise in non-communicable metabolic diseases (NCDs), particularly cardiovascular diseases (CVD) and diabetes. While modern pharmacotherapy has decreased the mortality in the existing population, it has failed to stem the rise. Furthermore, a large segment of the world population cannot afford expensive pharmacotherapy. Therefore, there is an urgent need for inexpensive preventive measures to control the rise in CVD and diabetes and associated co-morbidities. The purpose of this review is to explore the role of food bioactives in prevention of NCDs. To this end, we have critically analyzed the possible utility of three classes of food bioactives: (a) resistant starch, a metabolically resistant carbohydrate known to favorably modulate insulin secretion and glucose metabolism; (b) cyclo (His-Pro), a food-derived cyclic dipeptides; and (c) polyphenol-rich berries. Finally, we have also briefly outlined the strategies needed to prepare these food-bioactives for human use.

Contribution of dietary advanced glycation end products (AGE) to circulating AGE: role of dietary fat.

The purpose of this pilot study was to determine whether macronutrient content (low-fat v. high-fat diet) influences an indicator of advanced glycation end products (AGE), N(ε) carboxymethyl-lysine (CML), in the context of a 1-d, high-AGE diet. The effect of the diets on inflammatory markers was also assessed. A total of nineteen overweight and obese adults (nine men and ten women) without known disease were recruited to participate in a crossover challenge of a high-fat, high-AGE (HFHA) and low-fat, high-AGE (LFHA) diet. In each phase patients had fasting blood drawn, followed by consumption of a high-fat or low-fat breakfast test meal, then three postprandial blood draws at 1, 2 and 3 h after consuming the test meal. After consuming high-AGE meals for the remainder of the day, participants returned the next day for a follow-up analysis. A different pattern in the 3-h post-meal CML and soluble receptor for AGE response to the two diets was observed (P=0·01 and 0·05, respectively). No change in serum CML was observed following consumption of a LFHA breakfast (535 (25th-75th percentile 451-790) to 495 (25th-75th percentile 391-682) ng/ml; P=0·36), whereas a rise in CML occurred after the HFHA breakfast (463 (25th-75th percentile 428-664) to 578 (25th-75th percentile 474-865) ng/ml; P=0·05). High sensitivity C-reactive protein and high molecular weight adiponectin were not affected by either diet. These findings suggest that dietary CML may not be as important in influencing serum CML as other dietary factors. In addition, acute exposure to dietary CML may not influence inflammation in adults without diabetes or kidney disease. This is contrary to previous findings.

Women with osteoarthritis have elevated synovial fluid levels of insulin-like growth factor (IGF)-1 and IGF-binding protein-3.

The present study explores the possible connection between synovial fluid concentrations of insulin like growth factor (IGF-1), IGF-binding protein (IGFBP-3), leptin, and C-reactive protein (CRP) in osteoarthritis (OA). Synovial fluid specimens were obtained from a total of thirty-four individuals with and without OA. Protein-normalized measurements of IGF-1, IGFBP-3, and leptin concentrations in synovial fluid showed significantly (P < 0.05) elevated levels in women with knee OA but not in men. This study provides initial evidence that protein normalized IGF-1 and IGFBP-3 and leptin levels increase in synovial fluid of women but not in men with OA versus those without OA.

Serum soluble receptor for advanced glycation end products correlates inversely with measures of adiposity in young adults.

Advanced glycation end products (AGEs) may promote inflammation by interacting with the receptor for advanced glycation end products. Serum soluble receptor for advanced glycation end products (sRAGE), a form of receptor for advanced glycation end products thought to mediate AGE's inflammatory properties, is decreased in diabetes mellitus and coronary artery disease. Evidence in older adults suggests that sRAGE is depressed in individuals without current disease who are obese; however, 2 studies have failed to find this correlation. We hypothesized that sRAGE would be inversely correlated with adiposity and positively correlated with inflammation, even in apparently healthy, young adults. By considering adults of body mass index (BMI) varying from normal weight to overweight and obese, we aimed to define how closely AGEs and sRAGE correlate with adiposity and other indicators of metabolic stress. Anthropometric measurements and fasting blood samples were obtained from participants (n = 69). Sera were analyzed for sRAGE, n-epsilon carboxy-methyl-lysine, a measure of AGEs, and high sensitivity C-reactive protein. High molecular weight adiponectin, glucose, insulin, total cholesterol, high-density lipoprotein, and triacylglycerol were also assessed (n = 32). Spearman rank correlations were used to evaluate the relationship among indicators of adiposity and biochemical indicators of metabolic health and inflammation. Factors inversely correlated with sRAGE include weight (Rs = -0.397; P = .001), waist circumference (-0.291; P = .015), and BMI (-0.3338; P = .004). High molecular weight adiponectin was positively correlated with sRAGE, and predictors of sRAGE included BMI and total cholesterol. This is the first time these associations have been found in a diverse population of young adults.

Lifestyle and Advanced Glycation End Products (AGEs) Burden: Its Relevance to Healthy Aging.

Uncontrolled continued exposure to oxidative stress is a precursor to many chronic diseases including cancer, diabetes, degenerative disorders and cardiovascular diseases. Of the many known mediators of oxidative stress, reactive oxygen species (ROS) and advanced glycation end products (AGEs) are the most studied. In the present review, we have summarized current data on the origin of circulating AGEs, discussed issues associated with reliable assessment of its steady state level, and changes in its level with age and select metabolic diseases. Lastly, we have made recommendations about life style changes that may decrease AGEs burden to promote healthy aging.

Prescribing personalized nutrition for cardiovascular health: are we ready?

Of all chronic metabolic diseases, cardiovascular disease (CVD) is the leading cause of death worldwide. Most research over the past 100 years show a link between CVD and lifestyle, including diet; thus, public health messages have focused on modifications of the diet to better manage this disease. Despite this effort, the CVD mortality rate continues to rise. Therefore, is it possible that this failure may be due to individual variability in response to dietary recommendations? The elucidation of the structure of the human genome combined with the knowledge that nutrients are capable of modifying gene expression and genetic variability regulates how individuals respond to a diet have led to the possibility of personalized nutrition for disease prevention. While this possibility is real for the future, our current understanding of nutrient-gene interactions for CVD is limited, making personalized nutrition therapy difficult at this time. With advances in nutritional genomics, in the near future, dietitians and nutritionists will be able to give personalized nutritional advice based on a combination of lifestyle factors and genetics.

Sensory characteristics of high-amylose maize-resistant starch in three food products.

Type 2 resistant starch from high-amylose maize (HAM-RS2) is considered a functional ingredient due to its positive organoleptic and physiochemical modifications associated with food and physiological benefits related to human health. The sensory characteristics of three types of food products (muffins, focaccia bread, and chicken curry) with and without HAM-RS2 were evaluated using a 9-point hedonic scale. The HAM-RS2-enriched muffins, focaccia bread, and chicken curry contained 5.50 g/100 g, 13.10 g/100 g, and 8.94 g/100 g RS, respectively, based on lyophilized dry weight. The HAM-RS2-enriched muffin had higher moisture content and was perceived as being significantly moister than the control according to the sensory evaluation. The addition of HAM-RS2 to muffins significantly enhanced all sensory characteristics and resulted in a higher mean overall likeability score. The HAM-RS2-enriched focaccia bread appeared significantly darker in color, was more dense, and had the perception of a well-done crust versus the control. A grainer texture was observed with the chicken curry containing HAM-RS2 which did not significantly affect overall likeability. We concluded that the addition of HAM-RS2 may not significantly alter consumer's acceptability in most food products.

Soy protein with or without isoflavones failed to preserve bone density in gonadal hormone-deficient male rat model of osteoporosis.

Soy with its isoflavones has been shown to positively influence bone mineral density in female ovariectomized rats; hence, we hypothesized a similar effect in orchidectomized (ORX) male rats. Forty male Sprague-Dawley rats, aged 95 days, were divided into 4 groups and were either sham operated (Sham) or ORX. The ORX groups were fed a soy protein-based diet (SOY), an isoflavone-depleted soy protein diet (SOY-), or a casein based diet for 65 days after surgery. Orchidectomy increased the rate of bone turnover, resulting in reduced bone mineral density and bone mineral content by 3.5% and 14%, respectively, and compromised biomechanical properties. The mean femoral length of ORX animals was also significantly shorter than Sham animals, but ORX rats that were fed SOY diet did not experience this reduction in bone length, implicating a role for soy protein in bone growth (4.02 ± 0.02, 3.93 ± 0.01, 3.99 ± 0.02, 3.91 ± 0.01 for Sham, ORX, SOY, SOY-, respectively). The SOY and SOY- positively influenced the biomechanical properties of bone such as yield and ultimate force, the measures of bone elasticity, and plasticity. In terms of bone histomorphometry, the data indicate that SOY- tends to reduce ORX-induced increase in bone turnover as evidenced by suppressed bone formation rate/mineralized surface by about 9%. Overall, our results indicated that soy protein, regardless of its isoflavone content, was unable to prevent the ORX-induced femoral decrease in bone density and mineral content. However, soy may enhance the quality of bone as indicated by increased yield force.