Deep inspirations attenuate postprandial airway inflammation in college-aged adults with elevated baseline exhaled nitric oxide: A pilot study.

Airway inflammation (assessed by exhaled nitric oxide (eNO)) increases after a single high-fat meal (HFM), yet this response may be modified by airway stretch and baseline eNO level.Purpose: The purpose of this study was to investigate whether deep inspirations (DIs) would attenuate airway inflammation post-HFM and whether this is modulated by baseline eNO level.Methods: A total of sixteen healthy college-aged participants completed a randomized cross-over study with 8 lower eNO (14.8 ± 2.0 ppb: 3 M/5F; age: 22.0 ± 2.2 yrs) and 8 higher eNO (29.3 ± 11.6 ppb 5 M/3F; age: 22.5 ± 2.6 yrs) participants. All participants completed a control (CON) condition (no DIs pre-HFM) and DI condition (60 DI's to total lung capacity immediately pre-HFM) after an overnight fast. The primary outcome was eNO. Participants had 20 minutes to consume the HFM (1 g fat/1 kg body weight) and eNO was performed at 2- and 4- hours post-HFM. To determine whether baseline eNO levels impacted the effect of DI's, a median split was performed on their baseline eNO level.Results: There was a significant increase in eNO as a main effect of time (p < 0.001). However when analyzing the potential effect of baseline eNO, there was no significant increase in eNO post-HFM in the higher eNO group in the DI condition (p = 0.54). DIs modified the eNO response to a HFM in the group with a higher baseline eNO value.Conclusions: These data display a possible bronchoprotective protect of DIs against postprandial airway inflammation in participants with higher initial eNO level.

Postprandial Metabolic Responses Differ by Age Group and Physical Activity Level.

OBJECTIVES: To compare the postprandial metabolic responses to a high-fat meal in healthy adults who differ by age and physical activity level. DESIGN: Cross-sectional, quasi-experimental design. SETTING: Physical Activity and Nutrition Clinical Research Consortium (PAN-CRC) at Kansas State University (Manhattan, KS, USA). PARTICIPANTS: Twenty-two healthy adults: 8 younger active (YA) adults (4M/4W; 25 ± 5 yr), 8 older active (OA) adults (4M/4W; 67 ± 5 yr), and 6 older inactive (OI) adults (3M/3W; 68 ± 7 yr). INTERVENTION: Following an overnight (10-hour) fast and having abstained from exercise for 2 days, participants consumed a high-fat meal (63% fat, 34% CHO; 12 kcal/kg body mass; 927 ± 154 kcal). To assess the metabolic response, blood draws were performed at baseline and each hour following the meal for 6 hours. MEASUREMENTS: Fasting and postprandial triglycerides (TG), glucose, Total-C, and HDL-C were measured. Metabolic load index (MLI) and LDL-C were calculated. RESULTS: There were significant group x time interactions for TG (p < 0.0001) and MLI (p = 0.004). The TG total area-under-the-curve (tAUC) response was significantly lower in YA (407.9 ± 115.1 mg/dL 6 hr) compared to OA (625.6 ± 169.0 mg/dL 6 hr; p = 0.02) and OI (961.2 ± 363.6 mg/dL 6 hr; p = 0.0002), while the OA group TG tAUC was lower than the OI group (p = 0.02). The TG peak was significantly lower in YA (90.5 ± 27.0 mg/dL) than OA (144.0 ± 42.2 mg/dL; p = 0.03) and OI (228.2 ± 96.1 mg/dL; p = 0.0003), and was lower in the OA group compared to the OI group (p = 0.03). Glucose was significantly lower 1 hour after the meal in YA (89.4 ± 10.1 mg/dL; p = 0.01) and OA (87.3 ± 22.3 mg/dL; p = 0.005) versus OI (110.7 ± 26.9 mg/dL). MLI tAUC was significantly lower in YA (936.8 ± 137.7 mg/dL 6 hr; p = 0.0007) and OA (1133.0 ± 207.4 mg/dL; p = 0.01) versus OI (1553.8 ± 394.3 mg/dL), with no difference (p = 0.14) between YA and OA groups. Total-C and LDL-C were generally lower in younger compared to older participants at baseline and throughout the postprandial period, while no group or time effects were evident in HDL-C. CONCLUSION: Both physical activity status and aging appear to affect the postprandial metabolic, namely TG, response to a high-fat meal. These findings point to an inherently diminished metabolic capacity with aging, but suggest that physical activity may help minimize this decrement.

Post-prandial systemic 8-isoprostane increases after consumption of moderate and high-fat meals in insufficiently active males.

A single high-fat meal (HFM) leads to an increase in triglycerides and oxidative stress. Oxidative stress can be assessed via 8-isoprostane generation, which is associated with the development of asthma and cardiovascular disease. No previous research has investigated whether airway and systemic 8-isoprostane increases postprandially in nonasthmatic participants according to the energy and fat content of a meal. Our purpose was to assess airway and systemic 8-isoprostane after a HFM and a true-to-life moderate-fat meal (MFM). We hypothesized that airway and systemic 8-isoprostane would increase after a HFM and a MFM, with the greatest increase in the HFM condition. Eight nonasthmatic men (25.8±6.9years) completed the HFM and MFM trials in a randomized crossover design. After a 10-hour fast, participants consumed either a HFM (71.13kJ/kg body mass, 60% fat, 23% CHO) or a MFM (35.56kJ/kg body mass, 30% fat, 52% CHO). Exhaled breath condensate to assess airway 8-isoprostane was collected at baseline and at 3 and 6hours postmeal. Venous blood samples were collected at baseline and hourly until 6hours postmeal to assess triglycerides, and every 3hours for systemic 8-isoprostane. Airway 8-isoprostane responses were not significant as a main effect of time (P=.072), between conditions (P=.365), or between time and condition (P=.319) postmeal. Systemic 8-isoprostane increased over time (P<.001), but not between conditions (P=.124) or between time and condition (P=.649) postmeal. Triglyceride incremental area under the curve was different in the HFM compared to the MFM condition (P=.013). After a HFM and a MFM, 8-isoprostane increases systemically; however, airway 8-isoprostane does not change.