Angiopoietin-1 protects 3T3-L1 preadipocytes from saturated fatty acid-induced cell death.

Cross talk between endothelial cells and adipocytes is vital to adipocyte functions, but little is known about the mechanisms or factors controlling the process. Angiogenesis is a critical component linking the endothelium to healthy adipogenesis, yet it is not known if or how it is involved in adipocyte physiology. Therefore, the purpose of this study was to determine the effect of angiopoietin-1 (Ang-1) and -2 (Ang-2) as well as their receptor, Tie-2, on adipocyte physiology. 3T3-L1 pre- and mature adipocytes were found to express Ang-1, Ang-2, and Tie-2, which decrease upon polyunsaturated fatty acid treatment. Furthermore, 3T3-L1 cells treated with recombinant Ang-1 or Ang-2 increased expression of the antiapoptotic gene Bcl-x and decreased expression of the proapoptotic gene Casp-8. Next, preadipocytes were treated with saturated fatty acids (SFAs) to induce cell stress. SFA-mediated splicing of X-box-binding protein-1 was reduced by co-treatment with Ang-1, and cell viability was improved in the presence of SFAs + Ang-1. Taken together, these results indicate that Ang-1 may protect preadipocytes from SFA-induced apoptosis and endoplasmic reticulum stress.

A 7-day high-PUFA diet reduces angiopoietin-like protein 3 and 8 responses and postprandial triglyceride levels in healthy females but not males: a randomized control trial.

BACKGROUND: Polyunsaturated fatty acids (PUFAs) have beneficial effects on hypertriglyceridemia although their effect on angiopoietin-like proteins (ANGPTLs), specifically ANGPTL3, ANGPTL4 and ANGPTL8 is unknown. OBJECTIVE: To determine whether a high-PUFA diet improves postprandial triglyceride (TG) levels through reducing ANGPTL responses following high saturated fat (SFA) meals. METHODS: Twenty-six adults were randomized into a PUFA diet (n = 16) or a control diet group (n = 10). Participants completed a pre-diet visit (v1) where they were given two SFA-rich, high-fat meals. Blood draws were taken at fasting and every 2 h postprandially for a total of 8 h. After v1, participants completed a 7d diet of the same macronutrient proportions (50% carbohydrate, 35% fat, 15% protein) but with different fatty acid (FA) compositions (PUFA = 21% of total energy from PUFAs vs. Control = 7% of total energy from PUFA). All participants then completed the post-diet visit (v2) identical to v1. RESULTS: In the PUFA group, females, but not males, reduced TG concentrations (Area under the curve (AUC): 141.2 ± 18.7 vs. 80.7 ± 6.5 mg/dL/h, p = 0.01, for v1 vs. v2, respectively). Fasting and postprandial AUC levels of ANGPTL3 and 8, but not ANGPTL4, also decreased from v1 to v2 in PUFA females, but not males. No changes from v1 to v2 were seen in either sex in the control group. CONCLUSIONS: A PUFA-rich diet improves TG levels in response to high-SFA meals with reductions in ANGPTL3 and ANGPTL8. PUFAs may be more protective against hypertriglyceridemia in females, compared to males since no diet effect was observed in males. TRIAL REGISTRATION: NCT02246933.

Poor Performance of Children Age 7 to 13 Years on the Newest Vital Sign.

Valid and reliable instruments are needed to assess health literacy in children. Although the Newest Vital Sign (NVS) has been well established for use in adults, reports of its use in children have only recently received attention in the literature. Whereas some researchers have reported successful use of the NVS in children as young as age 7 years, others have suggested it is best used in children age 10 years and older. This analysis reports on the performance of the NVS in children age 7 to 13 years, adding to the growing evidence related to the use of the NVS in pediatric populations. Overall, children in this sample performed poorly on the NVS, which refutes previous reports. Differences in child samples and NVS administration procedures may provide some explanation for the lower-than-anticipated NVS performance in this sample. Interpreting the NVS based on educational standards and expectations may provide additional information to determine age-appropriate recommendations for NVS use in children. [HLRP: Health Literacy Research and Practice. 2018;2(4):e175-e179.].

Hunger and satiety responses to high-fat meals after a high-polyunsaturated fat diet: A randomized trial.

OBJECTIVE: Previous studies have shown that polyunsaturated fats (PUFAs) elicit a greater response in satiety after a single-meal challenge compared with other types of fats. The long-term effects of PUFAs on satiety, however, remain unknown. The aim of this study was to determine subjective and physiological hunger and satiety responses to high-fat (HF) meals before and after a 7-d PUFA-rich diet. METHODS: Twenty-six, healthy weight (body mass index 18-24.9 kg/m2), sedentary adults were randomly assigned to either a 7-d PUFA-rich diet (n = 8 men and n = 8 women) or a 7-d control diet (n = 5 men and n = 5 women). After a 3-d lead-in diet, participants reported for the baseline visit where anthropometrics, fasting visual analog scale (VAS) measurements, and a fasting blood sample were collected. Then, two HF meals (breakfast and lunch) were consumed. Postprandial blood draws and VAS measures were collected approximately every 30 min for 4 h after each meal, for a total of 8 h. RESULTS: From pre- to post-PUFA-rich diet, there was a decrease in fasting ghrelin (P < 0.05) and an increase in fasting peptide YY (PYY; P < 0.05); however, there were no changes in fasting insulin or leptin concentrations. The postprandial response for PYY was higher after the PUFA-rich diet visit compared to baseline (P < 0.01). However, there were no differences in the postprandial response for ghrelin, insulin, leptin, or VAS measures from pre- to post-diet in either the PUFA-rich diet or control (ns). CONCLUSION: A PUFA-rich diet consumed for 7 d favorably altered fasting and postprandial physiological markers of hunger and satiety; yet, did not alter subjective ratings of hunger or fullness.

A PUFA-rich diet improves fat oxidation following saturated fat-rich meal.

PURPOSE: To determine substrate oxidation responses to saturated fatty acid (SFA)-rich meals before and after a 7-day polyunsaturated fatty acid (PUFA)-rich diet versus control diet. METHODS: Twenty-six, normal-weight, adults were randomly assigned to either PUFA or control diet. Following a 3-day lead-in diet, participants completed the pre-diet visit where anthropometrics and resting metabolic rate (RMR) were measured, and two SFA-rich HF meals (breakfast and lunch) were consumed. Indirect calorimetry was used to determine fat oxidation (Fox) and energy expenditure (EE) for 4 h after each meal. Participants then consumed a PUFA-rich diet (50 % carbohydrate, 15 % protein, 35 % fat, of which 21 % of total energy was PUFA) or control diet (50 % carbohydrate, 15 % protein, 35 % fat, of which 7 % of total energy was PUFA) for the next 7 days. Following the 7-day diet, participants completed the post-diet visit. RESULTS: From pre- to post-PUFA-rich diet, there was no change in RMR (16.3 ± 0.8 vs. 16.4 ± 0.8 kcal/20 min) or in incremental area under the curve for EE (118.9 ± 20.6-126.9 ± 14.1 kcal/8h, ns). Fasting respiratory exchange ratio increased from pre- to post-PUFA-rich diet only (0.83 ± 0.1-0.86 ± 0.1, p < 0.05). The postprandial change in Fox increased from pre- to post-visit in PUFA-rich diet (0.03 ± 0.1-0.23 ± 0.1 g/15 min for cumulative Fox; p < 0.05), whereas controls showed no change. CONCLUSIONS: Adopting a PUFA-rich diet initiates greater fat oxidation after eating occasional high SFA meals compared to a control diet, an effect achieved in 7 days.

Echinacea-Based Dietary Supplement Does Not Increase Maximal Aerobic Capacity in Endurance-Trained Men and Women.

PURPOSE: To determine if an echinacea-based dietary supplement (EBS) provided at two different doses (a regular dose (RD), 8,000 mg/day, vs. a double dose (DD), 16,000 mg/day) would increase erythropoietin (EPO) and other blood markers involved in improving aerobic capacity and maximal oxygen consumption (VO2max) in endurance-trained men. Secondly, to determine if any sex differences exist between male and female endurance-trained athletes. METHODS: Forty-five endurance athletes completed three visits during a 35-day intervention. Participants were randomized into placebo (PLA; n = 8 men, n = 7 women), RD of EBS (n = 7 men, n = 8 women), or DD of EBS (n = 15 men) for the 35-day intervention period. At baseline, weight, body composition, and VO2max were measured. Blood was drawn to measure EPO, ferritin, red blood cells, white blood cells, hemoglobin, and hematocrit. At the mid-intervention visit, blood was collected. At the post-intervention visit, all measurements from the baseline visit were obtained once again. RESULTS: There was a significant increase in VO2max for endurance-trained men in PLA (increase of 2.8 ± 1.5 ml kg(-1) min(-1), p = .01) and RD of EBS (increase of 2.6 ± 1.8 ml kg(-1) min(-1), p = .04), but not in DD of EBS (p = .96). Importantly, there was no difference in the change in VO2max between PLA and RD of EBS. For endurance-trained women, VO2max did not change in either treatment (PLA: -0.7 ± 1.7 ml kg(-1) min(-1), p = .31; RD of EBS: -0.2 ± 2.4 ml kg(-1) min(-1), p = .80). There were no significant changes in any blood parameter across visits for any treatment group. CONCLUSIONS: This EBS should not be recommended as a means to improve performance in endurance athletes.

Hunger and satiety responses to high-fat meals of varying fatty acid composition in women with obesity.

OBJECTIVE: Determine subjective and physiological appetite responses and ad libitum intake to high-fat (HF) meals rich in either monounsaturated (MUFAs), polyunsaturated (PUFAs), or saturated fatty acids (SFAs) in women with obesity. METHODS: In this single-blind crossover study, three HF meals (70% of energy) rich in MUFAs, PUFAs, or SFAs in 16 women with obesity were tested. At each visit, anthropometrics and a fasting blood sample were collected. Participants then consumed one of the HF meals, and postprandial blood draws and visual analog scale (VAS) measures were collected over 5 h. An ad libitum buffet lunch was provided 5 h after the HF meal. RESULTS: Decrease in ghrelin was significantly greater for PUFA (P < 0.05) and MUFA (P < 0.01) vs. SFA while the increase in peptide YY was significantly greater for PUFA vs. both SFA and MUFA (P < 0.05). Change in glucagon-like peptide-1, VAS measurements, or total energy consumed at the buffet showed no differences between HF meals (ns). CONCLUSIONS: Fatty acid composition differentially affected physiological markers of hunger and satiety. However, it was unable to show changes in subjective appetite ratings or changes in energy intake when alterations were made to fatty acid composition from an acute HF meal.

Metabolic responses to dietary fatty acids in obese women.

BACKGROUND: The composition of fatty acids in a diet may differentially affect metabolism, thus playing a role in the development of obesity. Our purpose was to study the effects of three high-fat (HF) meals with different dietary fatty acid compositions on the thermic effect of meal (TEM) and substrate oxidation in obese premenopausal women. METHODS: 16 healthy obese women, aged 18-39 years, participated in a single-blinded randomized cross-over study, in which they consumed isocaloric HF meals (70% of energy from fat) rich in either saturated fat (SFA), monounsaturated fat (MUFA) or polyunsaturated fat (PUFA). Indirect calorimetry was used to measure respiratory gases for a 5-hour postprandial period. Data collected was used to determine respiratory exchange ratio (RER) for assessing substrate oxidation, and energy expenditure for the determination of TEM. RESULTS: There was a significant time effect on both substrate oxidation and TEM (p<0.05). With and without using RMR as a covariate, there were no significant differences in TEM between test meals (TEM of 10.8±0.8 vs 11.0±1.0 kcal ∗ 5 h for high-MUFA vs. high-SFA meals, respectively, p=0.06). No treatment difference was found for postprandial substrate utilization (4.9±0.4, 4.9±0.3 and 4.6±0.4 g of fat oxidation following SFA, MUFA, and PUFA-rich HF meals, respectively; 13.2±0.9, 13.3±0.5 and 13.9±0.6 g of carbohydrate oxidation following SFA, MUFA, and PUFA-rich HF meals, respectively). CONCLUSIONS: In premenopausal obese women, HF meals rich in either MUFAs, PUFAs, or SFAs did not differentially affect TEM or postprandial substrate oxidation.

Lipocalin-2 increases fat oxidation in vitro and is correlated with energy expenditure in normal weight but not obese women.

OBJECTIVE: The role of lipocalin-2 (Lcn2) was determined in regulating metabolism in cell, animal, and human models. DESIGN AND METHODS: Adipocytes were treated with recombinant lipocalin-2 (rLcn2) to determine the effect on lipid metabolism. rLcn2 was injected into mice to determine the effect on metabolism in vivo. To assess the relationship between Lcn2 and fat oxidation (FatOx) in humans, normal weight (NW) and obese (OB) women were given three separate high fat (HF) meals followed by indirect calorimetry. The relationship between postprandial Lcn2 with macronutrient metabolism and total energy expenditure (TEE) using Pearson correlations was determined. RESULTS: Lcn2 increased expression of genes involved in ß-oxidation including peroxisome proliferator-activated receptor-δ in adipocytes, as well as (3) H labeled oleate ß-oxidation. Lcn2 injected into chow-fed mice directly increased TEE by 18% after the first dark cycle (232 ± 1.4 cal vs. 341 ± 1.4 cal; PBS vs. Lcn2) and remained significantly elevated by 10% after the second dark cycle (296 ± 1.4 cal vs. 326 ± 1.4 cal; PBS vs. Lcn2). Lcn2 was correlated with TEE in all three HF meal challenges in NW but not OB females. CONCLUSIONS: Lipocalin-2 is a novel adipokine that promotes FatOx and TEE and its function may be impaired in obesity.

Age and sex differences pertaining to modes of locomotion in triathlon.

PURPOSE: The magnitude of change in sex differences across age groups in triathlon performance for the Ironman distance has been established. However, the influence of age on sex differences at shorter-distance triathlons is yet to be determined. The aim of this study was to compare sex differences across age groups for the different modes of locomotion among varying triathlon distances (Sprint, Olympic, and Ironman 70.3) in amateur triathletes from the 2009-2011 triathlon World Championship. METHODS: Data for the top 10 male and female amateur triathletes for the age groups between 18 and 64 yr were collected from the 2009-2011 World Championships for Sprint, Olympic, and Ironman 70.3 triathlons. Sex differences across age groups were compared using time performances for swimming, cycling, running, transition time, overall race time, and estimated power output. RESULTS: Total time differences between sexes were largest in 55-59 yr age groups for Sprint (18.7%, P < 0.05) and in 60-64 yr age groups for Olympic and Ironman 70.3 (14.8% and 21.7%, P < 0.05). Mean sex difference in performance time was smallest for cycling in Sprint (11.8% ± 0.41%) and in Ironman 70.3 (11.2% ± 0.41%), whereas running showed the smallest sex difference in Olympic (7.5% ± 0.33%, P < 0.05). Mean sex differences in estimated power output were significantly greater for swimming in Sprint (41.0% ± 1.47%), Olympic (39.8% ± 1.24%), and Ironman 70.3 (37.%5 ± 1.67%, P < 0.05). CONCLUSIONS: Sex differences for total performance time were greatest in the youngest age groups and older age groups for Sprint, Olympic, and Ironman 70.3 distances. Sex differences varied among the modes of locomotion for the three distances of triathlons; however, for short- to mid-distance triathlons, both performance time and estimated power output seem to indicate that the largest sex differences exist for swimming.