Diet Period Research Articles

Sow performance in response to natural betaine fed during lactation and post-weaning during summer and non-summer months

BackgroundTwo studies were conducted to evaluate the effects of dietary natural betaine on sow reproductive performance during summer (Exp. 1) and non-summer months (Exp. 2). Treatments were designed as a 2 × 2 factorial arrangement with factors including dietary betaine (0 or 0.2%) and period of supplementation (lactation or post-weaning until 35 days post-insemination). In Exp. 1, 322 and 327 sows and in Exp. 2, 300 and 327 sows representing young (parity 1 and 2) and mature (parity 3 to 6) sows, respectively, were used.ResultsIn Exp. 1, supplementation of betaine during lactation increased sow body weight losses (− 11.95 vs. −14.63 kg; P = 0.024), reduced feed intake (4.12 vs. 4.28 kg/d; P = 0.052), and tended to reduce percentage of no-value pigs (P = 0.071). Betaine fed post-weaning reduced weaning-to-estrus interval (5.75 vs. 6.68 days; P = 0.054) and farrowing rate (86.74% vs. 91.36%; P = 0.060), regardless of parity group. Post-hoc analysis with sows clustered into 3 parity groups (1, 2 and 3, and 4+) indicated that betaine fed in lactation to parity 4+ sows (P = 0.026) and betaine fed post-weaning to parity 1 sows increased the number of pigs born in the subsequent cycle (P ≤ 0.05). In Exp. 2, betaine fed during lactation tended to reduce the weaning-to-estrus interval (6.64 vs. 7.50 days; P = 0.077) and farrowing rate (88.23% vs. 83.54%; P = 0.089), regardless of parity group. Feeding betaine post-weaning reduced number of pigs born (13.00 vs. 13.64; P = 0.04) and pigs born alive (12.30 vs. 12.82; P = 0.075), regardless of parity group.ConclusionsUsing 0.2% betaine during the non-summer months did not benefit sow performance. During the summer, betaine supplementation in lactation increased subsequent litter size in parity 4+ sows. Betaine fed during the post-weaning period reduced the wean-to-estrus interval and farrowing rate, increased total number of pigs born for parity 1 sows and reduced total number of pigs born to parity 4+ sows. Further research is needed to determine if the detrimental effects on feed intake and farrowing rate may be correlated and depend on dietary betaine level.

Nondigestible Carbohydrates Affect Metabolic Health and Gut Microbiota in Overweight Adults after Weight Loss

The composition of diets consumed following weight loss (WL) can have a significant impact on satiety and metabolic health. This study was designed to test the effects of including a nondigestible carbohydrate to achieve weight maintenance (WM) following a period of WL. Nineteen volunteers [11 females and 8 males, aged 20-62 y; BMI (kg/m2): 27-42] consumed a 3-d maintenance diet (15%:30%:55%), followed by a 21-d WL diet (WL; 30%:30%:40%), followed by 2 randomized 10-d WM diets (20%:30%:50% of energy from protein:fat:carbohydrate) containing either resistant starch type 3 (RS-WM; 22 or 26g/d for females and males, respectively) or no RS (C-WM) in a within-subject crossover design without washout periods. The primary outcome, WM after WL, was analyzed by body weight. Secondary outcomes of fecal microbiota composition and microbial metabolite concentrations and gut hormones were analyzed in fecal samples and blood plasma, respectively. All outcomes were assessed at the end of each dietary period. Body weight was similar after the RS-WM and C-WM diets (90.7 and 90.8kg, respectively), with no difference in subjectively rated appetite. During the WL diet period plasma ghrelin increased by 36% (P<0.001), glucose-dependent insulinotropic polypeptide (GIP) decreased by 33% (P<0.001), and insulin decreased by 46% (P<0.001), but no significant differences were observed during the RS-WM and C-WM diet periods. Fasting blood glucose was lower after the RS-WM diet (5.59±0.31mmol/L) than after the C-WM diet [5.75±0.49mmol/L; P=0.015; standard error of the difference between the means (SED): 0.09]. Dietary treatments influenced the fecal microbiota composition (R2=0.054, P=0.031) but not diversity. The metabolic benefits, for overweight adults, from WL were maintained through a subsequent WM diet with higher total carbohydrate intake. Inclusion of resistant starch in the WM diet altered gut microbiota composition positively and resulted in lower fasting glucose compared with the control, with no apparent change in appetite. This trial was registered at clinicaltrials.gov as NCT01724411.

Time to adjust: changes in the diet of a reintroduced marsupial after release

AbstractAn important component of reintroduction is acclimatization to the release site. Movement parameters and breeding are common metrics used to infer the end of the acclimatization period, but the time taken to locate preferred food items is another important measure. We studied the diet of a reintroduced population of brushtail possumsTrichosurus vulpeculain semi-arid South Australia over a 12 month period, investigating changes over time as well as the general diet. We used next-generation DNA sequencing to determine the contents of 253 scat samples, after creating a local plant reference library. Vegetation surveys were conducted monthly to account for availability. Dietary diversity and richness decreased significantly with time since release after availability was accounted for. We used Jacob's Index to assess selectivity; just 13.4% of available plant genera were significantly preferred overall, relative to availability. The mean proportion of preferred plant genera contained within individual samples increased significantly with time since release, but the frequency of occurrence of preferred plants did not. Five genera (Eucalyptus,Petalostylis,Maireana,ZygophyllumandCallitris) were present in more than half of samples. There was no difference in dietary preferences between sexes (Pianka overlap = 0.73). Our results suggest that acclimatization periods may be longer than those estimated via reproduction, changes in mass and movement parameters, but that under suitable conditions a changeable diet should not negatively affect reintroduction outcomes. Reintroduction projects should aim to extend post-release monitoring beyond the dietary acclimatization period and, for dry climates, diet should be monitored through a drought period.

Anti-inflammatory Diet In Rheumatoid Arthritis (ADIRA)—a randomized, controlled crossover trial indicating effects on disease activity

BackgroundMany patients with rheumatoid arthritis (RA) report symptom relief from certain foods. Earlier research indicates positive effects of food and food components on clinical outcomes in RA, but insufficient evidence exists to provide specific dietary advice. Food components may interact but studies evaluating combined effects are lacking.ObjectivesWe aimed to investigate if an anti-inflammatory diet reduces disease activity in patients with RA.MethodsIn this single-blinded crossover trial, 50 patients with RA were randomly assigned to an intervention diet containing a portfolio of suggested anti-inflammatory foods, or a control diet similar to the general dietary intake in Sweden, for 10 wk. After a 4-mo washout period the participants switched diet. Food equivalent to ∼50% of energy requirements was delivered weekly to their homes. For the remaining meals, they were encouraged to consume the same type of foods as the ones provided during each diet. Primary outcome was change in Disease Activity Score in 28 joints-Erythrocyte Sedimentation Rate (DAS28-ESR). Secondary outcomes were changes in the components of DAS28-ESR (tender and swollen joints, ESR, and visual analog scale for general health) and DAS28-C-reactive protein.ResultsIn the main analysis, a linear mixed ANCOVA model including the 47 participants completing ≥1 diet period, there was no significant difference in DAS28-ESR between the intervention and control periods (P = 0.116). However, in unadjusted analyses, DAS28-ESR significantly decreased during the intervention period and was significantly lower after the intervention than after the control period in the participants who completed both periods (n = 44; median: 3.05; IQR: 2.41, 3.79 compared with median: 3.27; IQR: 2.69, 4.28; P = 0.04, Wilcoxon's Signed Rank test). No significant differences in the components were observed.ConclusionsThis trial indicates positive effects of a proposed anti-inflammatory diet on disease activity in patients with RA. Additional studies are required to determine if this diet can cause clinically relevant improvements.This trial was registered at clinicaltrials.gov as NCT02941055.

Effects of empagliflozin and L-ornithine L-aspartate on behavior, cognitive functions, and physical performance in mice with experimentally induced steatohepatitis

Non-alcoholic fatty liver disease (NAFLD) is a chronic condition characterized by disturbed carbohydrate and lipid metabolism and often complicated by psychoneurological symptoms, including anxiety, depression, memory deficit, and asthenia. Most studies of pharmacotherapy candidates for NAFLD focus on the ability of the tested drugs to restore the biochemical functions and morphology of the liver while their potential effects on the co-existing conditions remain overlooked. The aim of this paper was to investigate the effects of empagliflozin and L-ornithine L-aspartate (OA) on behavior, memory, and physical performance in C57BL/6 mice with experimentally induced NAFLD (6 months of a Western diet + weekly carbon tetrachloride injections). The disease affected animal behavior (locomotion speed decreased by 38% and 35%, p &lt; 0.01; rearing increased by 432% and 279%, p &lt; 0.05 etc.), induced long-term memory deficit (latency to find the target box increased by 108% in the Barnes maze, the number of errors increased by 439%, p &lt; 0.05), and compromised physical performance (swimming time in the forced swim test dropped by 50%, p &lt; 0.05 etc.). When administered during the high-calorie diet period, both drugs reduced anxiety (empagliflozin: the number of grooming bouts rose by 160%, p &lt; 0.05 and 2173%, p &lt; 0.01; time spent in the light compartment in the light/dark box test increased by 275%, p &lt; 0.05, etc.; OA: time spent in the open arms of the maze increased by 267%, p &lt; 0.05), and promoted memory retention in mice with NAFLD. OA improved physical performance (swimming time in the forced swimming test improved by 106%, p &lt; 0.05, etc.). Thus, empagliflozin and OA can have a beneficial effect on cognitive functions, as well as behavior, and ameliorate asthenia in NAFLD.

Consumption of Different Egg-Based Diets Impacts Body Composition in Young Healthy Adults

Abstract Objectives Consumption of whole eggs vs. egg whites has been associated with differential effects on satiety and post-exercise skeletal muscle synthesis. We investigated whether daily intake of whole eggs, egg whites, or an egg-free diet differentially altered markers of body composition in a general population of young healthy adults who were not participating in a standardized exercise program. Methods Young, healthy men and women (18–35y, BMI &amp;lt; 30 kg/m2, n = 26) participated in a randomized crossover intervention trial where they followed an egg-free diet for 4 weeks, then were randomized to consume either 3 whole eggs or 3 egg whites per day for 4 weeks. Subjects then followed a second 4-week egg-free diet washout period before switching to the alternative egg treatment. All subjects were instructed to maintain their baseline physical activity practices throughout the study. At the end of each diet period, body composition was measured by bioelectrical impedance and dietary nutrient intake was analyzed. Fasting serum samples were collected to measure fasting serum lipids, glucose, and markers of protein status. Results There were no differences in dietary intake of total calories, carbohydrates, or protein between the egg-free, whole egg, and egg white diet periods. There were similarly no differences in fiber, sucrose, or animal vs. vegetable protein intake between diet periods. Conversely, whole egg intake resulted in greater intake of vitamin D, cholesterol, and total, saturated, and monounsaturated fat. In assessing body composition, modest increases in body weight and body mass index were observed during the egg white period as compared to the whole egg and egg-free diet period. However, while changes in fat-free mass and muscle mass between diet periods did not reach significance, body fat mass was modestly increased following the whole egg diet as compared to the egg-free diet. No differences in fasting serum lipids, glucose, or markers of protein status were observed between diet periods. Conclusions Our findings indicate that different egg-based diets are associated with modest changes in body composition in young healthy adults. Funding Sources This study was funded by an Agriculture and Food Research Initiative Grant from the USDA National Institute of Food and Agriculture.

Effect of Mediterranean Diets with Varying Amounts of Lean Beef on Measures of Vascular Health

Abstract Objectives To evaluate the effects of Mediterranean (MED) diets with different quantities of lean beef (0.5, 2.5 and 5.5 oz/day) compared to an Average American diet (AAD) on brachial and central blood pressure, pulse wave velocity (PWV) and augmentation index (AI). Methods We conducted a multicenter, 4-period controlled feeding, randomized crossover study at Penn State University and USDA-Beltsville to evaluate the effects of MED diets (CHO 42%, PRO 17%, FAT 41%, SFA 8%, MUFA 26%, PUFA 8%) with different quantities of lean beef (0.5, 2.5 and 5.5 oz/day) compared to an average American diet (AAD; CHO 52%, PRO 15%, FAT 33%, SFA 12%, MUFA 13%, PUFA 8%) on vascular health. Participants (n = 66) included generally healthy males and females (BMI = 20–38 kg/m2) 30 to 67 years. Participants were randomized to each of the 4 diets for 4 weeks with an approximate 2-week break between treatments. Central blood pressure, PWV and AI were measured using the SphygmoCor ECEL-System. Endpoints were assessed at baseline and the end of each 4-week diet period. Results There was a significant treatment effect for PWV (P &amp;lt; 0.01); PWV was lower following consumption of the MED diets containing 0.5 oz. lean beef/day (6.86 m/sec ± 0.14; P &amp;lt; 0.05) and 2.5 oz. of lean beef/day (6.84 m/sec ± 0.15; P &amp;lt; 0.01) compared to the AAD (7.10 m/sec ± 0.14). Compared to the AAD, both the 0.5 oz./day (−3.30 mmHg ± 0.76) and 2.5 oz./day (−2.94 mmHg ± 0.76) MED diets elicited greater reductions in central systolic blood. A similar pattern was observed for central diastolic pressure. Compared to AAD, all three MED diets significantly decreased brachial systolic and diastolic pressures (P &amp;lt; 0.01 for all). Compared to baseline only the MED 0.5 elicited a significant reduction in AI (P &amp;lt; 0.01). Conclusions This study demonstrated improvements in measures of arterial stiffness and central blood pressure following Mediterranean diets containing low to moderate amounts of lean beef. Funding Sources National Cattleman's Beef Association, The Penn State Clinical and Translational Research Institute, Pennsylvania State University Clinical and Translational Science Award, and NIH/National Center for Advancing Translational Sciences grant no. UL1TR000127.

Fasting Glucose Response to Evening Snacks That Differ by Carbohydrate and Fat Composition: A 6-Week, Randomized, Crossover Trial in Subjects with Impaired Fasting Glucose

Abstract Objectives To examine the effect of consuming one ounce of peanuts (PNUT) as an evening snack on fasting plasma glucose and other cardiovascular disease risk factors, compared to an isocaloric lower fat higher carbohydrate snack (LFHC), in individuals with IFG. Methods Fifty-one individuals with IFG (52% male; 42 ± 15 y; BMI 28 ± 5.6 kg/m2; glucose 105 ± 4.9 mg/dL) were enrolled in this two-period, randomized, crossover trial. In random order, subjects consumed each snack in the evening (after dinner and before bedtime) for 6 weeks (PNUT: 164 kcal, 14 g fat, 2.2 g saturated fat, 6 g carbohydrate, 7 g protein, 2.4 g fiber; LFHC: 165 kcal, 6 g fat, 2 g saturated fat, 22 g carbohydrate, 7 g protein, 3.0 g fiber). Subjects were told not to consume other caloric foods/beverages after dinner. On two consecutive days at the beginning and end of each diet period a fasting blood sample was assessed for plasma glucose, serum lipids/lipoproteins, and insulin. Blood pressure (BP) and pulse wave velocity (PWV) were measured at each time point. Results Compared with baseline (100 mg/dL, 95% CI 99, 102), glucose was unchanged following both conditions (PNUT: −0.9 mg/dL 95% CI −2.1, 1.3; LFHC: −0.4 mg/dL 95% CI −2.6, 0.8) with no between-condition difference (P &amp;gt; 0.05). Changes for LDL-C from baseline differed between conditions (−4.8 mg/dL; 95% CI −9.2, −0.4); there were no within-condition changes from baseline (LFHC −2.3 mg/dL, 95% CI −5.7, 1.0; PNUT 2.5 mg/dL, 95% CI −0.9, 5.8). Greater triglyceride lowering was observed with PNUT (−17 mg/dL, 95% CI −28, −6.2) vs. LFHC (−5.7 mg/dL, 95% CI −17, 5.1). There were no condition effects for weight, HDL-C, insulin, BP or PWV. In a post hoc analysis of subjects who had IFG (&amp;gt;99 mg/dL) at baseline (107 mg/dL, 95% CI 106, 108), glucose was lowered compared to baseline for both conditions (PNUT: −2.6 mg/dL, 95% CI −4.6, −0.6; LFHC: −3.1 mg/dL, 95% CI −5.1, −1.0). Conclusions In individuals with IFG, consuming a relatively low-calorie, mixed macronutrient, nighttime snack improves fasting glucose levels. Greater reductions in triglycerides were observed with evening peanut consumption, which may be explained by the lower carbohydrate and higher fat content. Funding Sources The Peanut Institute Supported by the National Center for Advancing Translational Sciences, National Institutes of Health.

Technical details for harvesting gastro-epiploic lymph node flaps via mini-laparotomy incision

Laparoscopic harvest method to obtain gastro-epiploic lymph node flaps for lymphedema treatment has been previously described. In this article, the technical details of an alternative method - open approach via mini-laparotomy incision - for harvesting gastro-epiploic lymph node flaps and preparation of the flaps for the inset is presented. A total of 17 patients were included in this series of the mini-laparotomy approach. Blood loss was minimal during the surgery. The average duration of lymph node flap harvest was 65min. The average length of hospital stay was 10 days. The period of the restricted diet was 1.5 days. The upper abdominal scar was acceptable, there were no postoperative hernia or bulging, and there were no complications related to bowel obstruction during the follow-up. The open approach harvest method via mini-laparotomy incision offers similar results to laparoscopic harvest method, and it is safe when applied with the right technique.

Safety and feasibility of various fasting-mimicking diets among people with multiple sclerosis

BackgroundFasting-mimicking diets have shown promise in experimental autoimmune encephalitis and are currently being investigated among people with multiple sclerosis (MS). Ensuring adherence to diet changes is critical to determining the efficacy of such interventions. ObjectiveOur primary aim was to evaluate the safety and feasibility of several fasting-mimicking diets and investigate whether various levels of clinical support improve diet adherence among people with MS. Secondarily, this study evaluated the impact of fasting-mimicking diets on weight and patient-reported outcomes (PROs). MethodsWe conducted three pilot studies (two randomized controlled for 6 months; one randomized with transition to single arm) restricting either the amount or timing of calorie intake over 24 or 48 weeks. Interventions included calorie restriction (daily or intermittently) or time-restricted feeding. Adherence measures varied across studies but were collected at study visits along with weight and PRO data. ResultsA total of 90 participants enrolled; 70 completed the studies, with no serious adverse events reported. Overall adherence to the calorie restriction diets was poor. When participants were tasked with maintaining a diet in a pragmatic setting, neither previously completed intense clinical support and education, nor weekly electronic communication throughout the diet period appeared to improve diet adherence. Participants who were able to adhere to a calorie restriction diet predictably lost weight. In contrast to calorie restriction, adherence to a time-restricted feeding (TRF) diet was relatively good. No statistically significant changes in PROs were observed in an intention-to-treat analysis. ConclusionThe role diet may play in clinical outcomes in MS remains unknown, as class I evidence is lacking. Diet adherence remains a primary barrier to the feasible conduct of large, randomized controlled diet trials. Strict adherence to a TRF dietary change may be more feasible than calorie restriction and should be considered in future fasting-mimicking diet trials. ClinicalTrials.gov Registry:A Pilot Study of Intermittent Calorie Restriction in Multiple Sclerosis – NCT02647502. A Pragmatic Trial of Dietary Programs in People with Multiple Sclerosis (MS) – NCT02846558

Effect of long-term overfeeding of a high-energy diet on glucose tolerance in Shetland pony mares.

BackgroundOverfeeding is associated with obesity and insulin dysregulation (ID), which are both risk factors for equine metabolic syndrome. How chronic overfeeding affects development of these factors is poorly understood.ObjectivesTo examine the influence of long‐term high‐energy diet provision on body condition and ID.AnimalsEleven Shetland pony mares.MethodsIn a 3‐phase study, the high‐energy group (n = 7) was fed 200% of net energy (NE) requirements (hay; concentrate: 36% sugar and starch, 13% fat) for 24 weeks, followed by 17 weeks hay‐only feeding before resuming the high‐energy diet (n = 4) for an additional 29 weeks. Mares were weighed weekly. Oral glucose tolerance tests were performed 3 to 4 times per dietary period. Results were compared with those of a control group (phase 1, n = 4; phases 2 and 3, n = 6) that received 100% NE requirements, using a general linear mixed model with post hoc Bonferroni testing.ResultsThe mean body weight of the high‐energy group increased by 27% per high‐energy feeding period. During both feeding periods, area under the curve (AUC) for plasma glucose concentration decreased (P < .01), whereas AUC for plasma insulin concentration increased. Mean basal plasma glucose concentration and peak plasma insulin concentrations were higher (P < .05) in the high‐energy group than in the control group.Conclusion and Clinical ImportanceFeeding a high‐energy diet to healthy nonobese Shetland pony mares led to more efficient glucose metabolism within 5 weeks, followed by significant hyperinsulinemia and obesity. Hyperinsulinemic status was reversed during 17 weeks of hay‐only feeding, regardless of body condition, but returned rapidly after restarting the high‐energy diet.

Development of omega-3 rich eggs through dietary flaxseed and bio-evaluation in metabolic syndrome.

An egg is a nutrient‐dense food that contains protein, fats, vitamins, and minerals. It is proven that the consumption of eggs influences serum lipid concentration. Therefore, a study was conducted to investigate the effect of normal and omega‐3 eggs on serum lipids profiles. Lipids were extracted from egg yolks and analyzed for fatty acids content. The present research is a crossover study design in which 20 participants were recruited randomly, and all subjects received three treatments: no eggs, omega‐3 eggs, and normal eggs. However, fasting blood was drawn at baseline and the end of each diet period and analyzed for serum lipids, blood glucose, and insulin level. Omega‐3 egg treatment showed reduction in the serum total cholesterol by 16.57 mg/dl (p < .001), triglyceride by 17.48 mg/dl, and increase in HDL cholesterol concentration by 0.48 mg/dl (p < .001) as compared to no‐egg. A significant (p < .05) reduction in blood pressure by 8.34/8.67 mm/Hg and insulin level was observed due to omega‐3 egg consumption which indicates that omega‐3 fatty acids improve insulin sensitivity. On the other hand, regular egg intake elevates serum total cholesterol and triglycerides concentration but decreases blood pressure. It was concluded that omega‐3‐enriched egg consumption had a positive effect on the serum lipid profile and blood pressure of patients with metabolic syndrome as compared to normal eggs.

Replacing Saturated Fats with Unsaturated Fats from Walnuts or Vegetable Oils Lowers Atherogenic Lipoprotein Classes Without Increasing Lipoprotein(a)

ABSTRACTBackgroundWalnuts have established lipid-/lipoprotein-lowering properties; however, their effect on lipoprotein subclasses has not been investigated. Furthermore, the mechanisms by which walnuts improve lipid/lipoprotein concentrations are incompletely understood.ObjectivesWe aimed to examine, as exploratory outcomes of this trial, the effect of replacing SFAs with unsaturated fats from walnuts or vegetable oils on lipoprotein subclasses, cholesterol efflux, and proprotein convertase subtilisin/kexin type 9 (PCSK9).MethodsA randomized, crossover, controlled-feeding study was conducted in individuals at risk of cardiovascular disease (CVD) (n = 34; 62% men; mean ± SD age 44 ± 10 y; BMI: 30.1 ± 4.9 kg/m2). After a 2-wk run-in diet (12% SFAs, 7% PUFAs, 12% MUFAs), subjects consumed the following diets, in randomized order, for 6 wk: 1) walnut diet (WD) [57–99 g/d walnuts, 7% SFAs, 16% PUFAs [2.7% α-linolenic acid (ALA)], 9% MUFAs]; 2) walnut fatty acid–matched diet [7% SFAs, 16% PUFAs (2.6% ALA), 9% MUFAs]; and 3) oleic acid replaces ALA diet (ORAD) [7% SFAs, 14% PUFAs (0.4% ALA); 12% MUFAs] (all percentages listed are of total kilocalories ). Serum collected after the run-in (baseline) and each diet period was analyzed for lipoprotein classes and subclasses (vertical auto profile), cholesterol efflux, and PCSK9. Linear mixed models were used for data analysis.ResultsCompared with the ORAD, total cholesterol (mean ± SEM −8.9± 2.3 mg/dL; −5.1%; P < 0.001), non-HDL cholesterol (−7.4 ± 2.0 mg/dL; −5.4%; P = 0.001), and LDL cholesterol (−6.9 ± 1.9 mg/dL; −6.5%; P = 0.001) were lower after the WD; no other pairwise differences existed. There were no between-diet differences for HDL-cholesterol or LDL-cholesterol subclasses. Lipoprotein(a) [Lp(a)], cholesterol efflux, and PCSK9 were unchanged after the diets.ConclusionsIn individuals at risk of CVD, replacement of SFAs with unsaturated fats from walnuts or vegetable oils improved lipid/lipoprotein classes, including LDL-cholesterol, non-HDL cholesterol, and total cholesterol, without an increase in Lp(a). These improvements were not explained by changes in cholesterol efflux capacity or PCSK9. This trial was registered at clinicaltrials.gov as NCT01235832.

A 1-week extension of a ketogenic diet provides a further decrease in myocardial 18F-FDG uptake and a high detectability of myocarditis with FDG-PET

BackgroundShort periods of fasting and/or low-carbohydrate diet have been proven beneficial for decreasing the myocardial uptake of 18F-fluorodeoxyglucose (18F-FDG) and enhancing the detection of inflammatory heart diseases by 18F-FDG positron emission tomography (PET). This study aimed at determining whether this benefit is increased when a low-carbohydrate ketogenic diet is prolonged up to 7 days. MethodsWistar rats underwent serial 18F-FDG-PET imaging after an 18-hour fasting period and after 2, 4 and 7 days of a ketogenic diet (3% carbohydrate) and they were compared to rats submitted to the same protocol but with normal diet (44% carbohydrate). The 18F-FDG-PET/ketogenic protocol was also applied in rats with immune myocarditis (injection of porcine cardiac myosin). ResultsThe 7-day ketogenic diet was associated with (1) a sustained increase in circulating ketone bodies at an equivalent level to that reached after 18-hour fasting, (2) a gradual decrease in 18F-FDG uptake within normal myocardium reaching a lower level compared to fasting at the 7th day (myocardium-to-blood ratios: 1.68 ± 1.02 vs 3.25 ± 1.40, P < .05) and (3) a high 18F-FDG-PET detectability of myocarditis areas. ConclusionOne-week extension of a ketogenic diet provides a further decrease in the 18F-FDG uptake of normal myocardium and a high detectability of inflammatory areas.

Persistent Changes in Salt Intake by Estrogen‐Treated Rats after Repeated Episodes of Dietary Sodium Deficiency

AimsPrevious research from our lab and others demonstrated sex differences in sodium intake, though estrogen’s role in these differences is unclear. Further, previous studies analyzing salt intake with repeated episodes of sodium depletion using furosemide showed that stimulated salt intake was similar between males and females; however, there were clear sex differences in sodium intake after rats were no longer sodium depleted. We aimed to further elucidate the long‐term effects of estrogen on sodium intake using repeated episodes on a low salt diet, a more physiological challenge.MethodsOvariectomized rats were placed on two‐week periods of access to regular chow (NaR) or sodium deficient chow (NaD), which we alternated for a total of two exposures to each diet. Estrogen benzoate (EB) or oil injections were given twice weekly throughout the experiment. At the end of each diet period, rats were given a 2‐hour two bottle test (water and 0.5 M NaCl). At the end of the experiment, rats were sacrificed and trunk blood was collected and centrifuged to collect plasma. Plasma protein levels were measured. Uteri were collected and 1 cm segments of the uterine horns were weighed.ResultsWe confirmed the efficacy of EB treatment on body weight, uterine weight, and plasma proteins. As expected, EB‐treated rats maintained body weight throughout the experiment, with transient decreases, while oil‐treated rats gained weight. Both plasma proteins and uterine weights were greatly increased in EB‐treated compared to oil rats. During two‐bottle tests, both EB‐ and oil‐treated rats had similar baseline intakes of 0.5 M NaCl and water. When salt intake was stimulated by dietary sodium deficiency, both EB‐ and oil‐treated rats drank similarly increased amounts of 0.5 M NaCl. Interestingly, EB‐treated rats drank more 0.5 M NaCl and water than oil‐treated rats after returning to regular chow. The period of dietary sodium deficiency again elicited similar intakes of 0.5 M NaCl and water by EB‐ and oil‐treated rats.ConclusionsOur study demonstrated that estrogen did not alter induced salt intake induced by the physiological challenge, dietary sodium deficiency. However, the low salt diet led to persistent changes in behavior, as demonstrated by the continued consumption of salt and water by EB‐treated rats even after lost dietary sodium was replenished.

FASTING-MIMICKING DIET a clarion call for human nutrition research or an additional swan song for a commercial diet?

Numerous studies have reported beneficial effects for fasting in cellular and animal models, but human studies have shown conflicting results. Recently, a new diet has been introduced both in the scientific literature and in the lay media, the so-called fasting-mimicking diet. It is mainly characterised by a diet period that imitates fasting (generally 4–5 consecutive days) consisting of low or very low-calorie intake with a low or very low contribution of carbohydrates and proteins and a high fat intake. This protocol has been tested in some experimental animal models that have studied different outcomes, and in two small clinical trials that have reported some alleged beneficial effects especially on cardio-metabolic risk parameters. However, these clinical trials suffer from many limitations that require attention. The purpose of the present paper is to review the experimental and clinical studies that have investigated this particular dietary approach and to critically discuss the results.

Human Peripheral Blood Gamma Delta T Cells: Report on a Series of Healthy Caucasian Portuguese Adults and Comprehensive Review of the Literature.

Gamma delta T cells (Tc) are divided according to the type of Vδ and Vγ chains they express, with two major γδ Tc subsets being recognized in humans: Vδ2Vγ9 and Vδ1. Despite many studies in pathological conditions, only a few have quantified the γδ Tc subsets in healthy adults, and a comprehensive review of the factors influencing its representation in the blood is missing. Here we quantified the total γδ Tc and the Vδ2/Vγ9 and Vδ1 Tc subsets in the blood from 30 healthy, Caucasian, Portuguese adults, we characterized their immunophenotype by 8-color flow cytometry, focusing in a few relevant Tc markers (CD3/TCR-γδ, CD5, CD8), and costimulatory (CD28), cytotoxic (CD16) and adhesion (CD56) molecules, and we examined the impacts of age and gender. Additionally, we reviewed the literature on the influences of race/ethnicity, age, gender, special periods of life, past infections, diet, medications and concomitant diseases on γδ Tc and their subsets. Given the multitude of factors influencing the γδ Tc repertoire and immunophenotype and the high variation observed, caution should be taken in interpreting “abnormal” γδ Tc values and repertoire deviations, and the clinical significance of small populations of “phenotypically abnormal” γδ Tc in the blood.

Comparative digestibility of polysaccharide-complexed zinc and zinc sulfate in diets for gestating and lactating sows.

We hypothesized that the digestibility of a zinc polysaccharide complex is greater than zinc sulfate when sows consume high fiber diets containing corn dried distillers grains with solubles (DDGS). Gilts and sows (n = 32) were blocked according to parity and assigned randomly to one of four dietary treatments (n = 8 sows per treatments). Dietary treatments consisted of: 1) Control (ConZnSO4)-corn-soybean meal-based diet + 100 ppm supplemental Zn from ZnSO4; 2) Control PSZn (ConPSZn)-corn-soybean meal-based diet + 100 ppm supplemental Zn from Zn polysaccharide complex; 3) DDGS/ZnSO4-corn-soybean meal-40% DDGS gestation diet and a 30% DDGS lactation diet, with each containing 100 ppm supplemental Zn from ZnSO4; 4) DDGS/PSZn-corn-soybean meal-40% DDGS gestation diet and a 30% DDGS lactation diet, with each containing 100 ppm supplemental Zn from Zn polysaccharide complex. A fifth dietary treatment was imposed using a subset of sows (n = 20) to determine basal Zn losses in gestating and lactating sows fed corn-soybean meal-based diets containing no supplemental Zn. Nutrient balance experiments were conducted in both gestation and lactation to evaluate the digestibility of Zn sources of the four dietary treatments and to determine basal Zn losses when no supplemental Zn was provided. The statistical model included fixed effects of diet, Zn source, and their interaction, and random effects of parity. Estimated endogenous losses of Zn were used to adjust apparent total tract digestibility (ATTD) to true total tract digestibility (TTTD) of Zn in the four dietary treatment balance periods. There were no differences in Zn concentrations of urine, plasma, colostrum, or milk samples among treatments at any time of the experiment (P > 0.05). Gestating sows fed DDGS/PSZn had improved (P < 0.05) ATTD, TTTD, and overall retention of Zn compared with both Control treatments, with the DDGS/ZnSO4 treatment responses being intermediate. Lactating sows consuming diets without DDGS and supplemented with Zn polysaccharide complex had the greatest (P < 0.05) ATTD, TTTD, and retention of Zn, which were opposite to responses observed in gestation. Furthermore, ATTD, TTTD, and Zn retention for lactating sows consuming DDGS/PSZn were less (P < 0.05) than all other treatments. Overall, zinc digestibility of ZnSO4 and PSZn appears to be differentially influenced by the stage of the reproductive cycle and presence of dietary fiber from DDGS.

Gut Microbial Protein Expression in Response to Dietary Patterns in a Controlled Feeding Study: A Metaproteomic Approach.

Although the gut microbiome has been associated with dietary patterns linked to health, microbial metabolism is not well characterized. This ancillary study was a proof of principle analysis for a novel application of metaproteomics to study microbial protein expression in a controlled dietary intervention. We measured the response of the microbiome to diet in a randomized crossover dietary intervention of a whole-grain, low glycemic load diet (WG) and a refined-grain, high glycemic load diet (RG). Total proteins in stools from 9 participants at the end of each diet period (n = 18) were analyzed by LC MS/MS and proteins were identified using the Human Microbiome Project (HMP) human gut microbiome database and UniProt human protein databases. T-tests, controlling for false discovery rate (FDR) <10%, were used to compare the Gene Ontology (GO) biological processes and bacterial enzymes between the two interventions. Using shotgun proteomics, more than 53,000 unique peptides were identified including microbial (89%) and human peptides (11%). Forty-eight bacterial enzymes were statistically different between the diets, including those implicated in SCFA production and degradation of fatty acids. Enzymes associated with degradation of human mucin were significantly enriched in the RG diet. These results illustrate that the metaproteomic approach is a valuable tool to study the microbial metabolism of diets that may influence host health.

Effects of high-fiber diets enriched with carbohydrate, protein, or unsaturated fat on circulating short chain fatty acids: results from the OmniHeart randomized trial

Short chain fatty acids (SCFAs; e.g., acetate, propionate, and butyrate) are produced by microbial fermentation of fiber in the colon. Evidence is lacking on how high-fiber diets that differ in macronutrient composition affect circulating SCFAs. We aimed to compare the effects of 3 high-fiber isocaloric diets differing in %kcal of carbohydrate, protein, or unsaturated fat on circulating SCFAs. Based on previous literature, we hypothesized that serum acetate, the main SCFA in circulation, increases on all high-fiber diets, but differently by macronutrient composition of the diet. OmniHeart is a randomized crossover trial of 164 men and women (≥30 y old); 163 participants with SCFA data were included in this analysis. We provided participants 3 isocaloric high-fiber (∼30 g/2100 kcal) diets, each for 6 wk, in random order: a carbohydrate-rich (Carb) diet, a protein-rich (Prot) diet (protein predominantly from plant sources), and an unsaturated fat-rich (Unsat) diet. We used LC-MS to quantify SCFA concentrations in fasting serum, collected at baseline and the end of each diet period. We fitted linear regression models with generalized estimating equations to examine change in ln-transformed SCFAs from baseline to the end of each diet; differences between diets; and associations of changes in SCFAs with cardiometabolic parameters. From baseline, serum acetate concentrations were increased by the Prot (β: 0.24; 95% CI: 0.12, 0.35), Unsat (β: 0.21; 95% CI: 0.10, 0.33), and Carb (β: 0.12; 95% CI: 0.01, 0.24) diets; between diets, only Prot compared with Carb was significant (P=0.02). Propionate was decreased by the Carb (β: -0.10; 95% CI: -0.16, -0.03) and Unsat (β: -0.10; 95% CI: -0.16, -0.04) diets, not the Prot diet; between diet comparisons of Carb vs. Prot (P=0.006) and Unsat vs. Prot (P=0.002) were significant. The Prot diet increased butyrate (β: 0.05; 95% CI: 0.00, 0.09) compared with baseline, but not compared with the other diets. Increases in acetate were associated with decreases in insulin and glucose; increases in propionate with increases in leptin, LDL cholesterol, and blood pressure; and increases in butyrate with increases in insulin and glucose, and decreases in HDL cholesterol and ghrelin (Ps<0.05). Macronutrient composition of high-fiber diets affects circulating SCFAs, which are associated with measures of appetite and cardiometabolic health. This trial was registered at clinicaltrials.gov as NCT00051350.