Dairy protein, exercise and inflammatory markers in older adults

We have investigated the effects of adding dairy protein to the diet of older adults on muscle mass, muscle strength, physical performance and inflammation, and if there are differences in the response of immune-related markers in skeletal muscle and white blood cells (PBMCs) after strength exercise combined with different protein source (milk and whey). Compared to an isocaloric carbohydrate drink, increased protein intake did not improve the markers investigated, and different types of dairy protein exerted similar effects on immune-related markers. However, combined strength training and protein supplementation caused an acute increase of several immune-related markers in both skeletal muscle and PBMCs, possibly being important contributors to muscle repair, regeneration and adaptive processes. Eleven weeks of strength training caused reduced levels of immune-related markers in PBMCs, possibly contributing to the immune-modulating effects observed after exercise. Furthermore, skeletal muscle and PBMCs may provide complementary insight into the molecular response to exercise and protein supplementation rather than simply reflecting each other

Effects of Exercise on Gene Expression of Inflammatory Markers in Human Peripheral Blood Cells: A Systematic Review

Regular physical activity seems to be one of the most important contributors to prevent disease and promote health. Being physically active reduces the risk of developing chronic diseases such as cardiovascular disease, diabetes, and some types of cancers. The molecular mechanisms are however not fully elucidated. Depending on duration and intensity, exercise will cause disruption of muscle fibers triggering a temporary inflammatory response. This response may not only involve the muscle tissue, but also peripheral tissues such as white blood cells, which are important components of the immune system. The immune system plays a vital role in the development of atherosclerosis, thereby making white blood cells relevant to study when looking at molecular mechanisms induced by physical activity. In this review, we summarize the existing literature on exercise and gene expression in human white blood cells, and discuss these results in relation to inflammation and atherosclerosis

Effects of Exercise on Gene Expression of Inflammatory Markers in Human Peripheral Blood Cells: A Systematic Review

Regular physical activity seems to be one of the most important contributors to prevent disease and promote health. Being physically active reduces the risk of developing chronic diseases such as cardiovascular disease, diabetes, and some types of cancers. The molecular mechanisms are however not fully elucidated. Depending on duration and intensity, exercise will cause disruption of muscle fibers triggering a temporary inflammatory response. This response may not only involve the muscle tissue, but also peripheral tissues such as white blood cells, which are important components of the immune system. The immune system plays a vital role in the development of atherosclerosis, thereby making white blood cells relevant to study when looking at molecular mechanisms induced by physical activity. In this review, we summarize the existing literature on exercise and gene expression in human white blood cells, and discuss these results in relation to inflammation and atherosclerosis

Facilitators and barriers to healthy food selection at children’s sports arenas in Norway: a qualitative study among club managers and parents

Objective: To investigate club managers’ and parents’ experiences with food selec- tion at handball halls in order to identify facilitators and barriers to the availability of healthy food. Design: Individual interviews with club managers (n 6) and focus groups (n 5) with parents (n 21) were conducted. Interviews were recorded and transcribed verba- tim, transcripts were coded in NVivo and the analysis was guided by thematic analysis. Setting: Interviews were conducted at five handball clubs with varying socio- economic user populations and sizes in the area of Oslo, Norway. Participants: The club managers were responsible for food selection at the hand- ball clubs. The participating parents had one or two active children between the ages of 6 and 12 years who took part in the clubs. Results: The club managers and parents generally described food selection at the handball halls as unhealthy and wanted a healthier selection of food. The club managers’ primary barriers to providing a healthier food selection included the potential to lose profits, limited facilities and time to prepare these foods. The parents often valued unhealthy food, as they believed that it supported the social environment and served as a reward for the children. Trainers were perceived as important role models for the promotion of healthy eating. The participants thought that national guidelines could facilitate healthy food environments in sports arenas. Conclusion: Healthier food options in sports settings could be facilitated through national guidelines that describe healthy foods and establish who is responsible for providing healthy food selections

Sex differences in postprandial responses to different dairy products on lipoprotein subclasses: A randomised controlled cross-over trial

Men have earlier first-time event of CHD and higher postprandial TAG response compared with women. The aim of this exploratory sub-study was to investigate if intake of meals with the same amount of fat from different dairy products affects postprandial lipoprotein subclasses differently in healthy women and men. A total of thirty-three women and fourteen men were recruited to a randomised controlled cross-over study with four dairy meals consisting of butter, cheese, whipped cream or sour cream, corresponding to 45 g of fat (approximately 60 energy percent). Blood samples were taken at 0, 2, 4 and 6 h postprandially. Lipoprotein subclasses were measured using NMR and analysed using a linear mixed model. Sex had a significant impact on the response in M-VLDL (P=0·04), S-LDL (P=0·05), XL-HDL (P=0·009) and L-HDL (P=0·001) particle concentration (P), with women having an overall smaller increase in M-VLDL-P, a larger decrease in S-LDL-P and a larger increase in XL- and L-HDL-P compared with men, independent of meal. Men showed a decrease in XS-VLDL-P compared with women after intake of sour cream (P<0·01). In men only, XS-VLDL-P decreased after intake of sour cream compared with all other meals (v. butter: P=0·001; v. cheese: P=0·04; v. whipped cream: P=0·006). Meals with the same amount of fat from different dairy products induce different postprandial effects on lipoprotein subclass concentrations in men and women

Intake of fermented dairy products induces a less pro-inflammatory postprandial peripheral blood mononuclear cell gene expression response than non-fermented dairy products: A randomized controlled cross-over trial

Scope - It is aimed to investigate how intake of high‐fat meals composed of different dairy products with a similar fat content affects postprandial peripheral blood mononuclear cell (PBMC) expression of inflammation‐related genes, as well as circulating inflammatory markers and metabolites. Methods and results - Healthy subjects (n = 47) consume four different high‐fat meals composed of either butter, cheese, whipped cream, or sour cream in a randomized controlled cross‐over study. Fasting and postprandial PBMC gene expression, plasma metabolites, and circulating inflammatory markers are measured. Using a linear mixed model, it is found that expression of genes related to lymphocyte activation, cytokine signaling, chemokine signaling, and cell adhesion is differentially altered between the four meals. In general, intake of the fermented products cheese and sour cream reduces, while intake of the non‐fermented products butter and whipped cream increases, expression of these genes. Plasma amino acid concentrations increase after intake of cheese compared to the other meals, and the amino acid changes correlate with several of the differentially altered genes. Conclusion - Intake of fermented dairy products, especially cheese, induces a less inflammatory postprandial PBMC gene expression response than non‐fermented dairy products. These findings may partly explain inconsistent findings in studies on health effects of dairy products

Consumption of protein-enriched milk has minor effects on inflammation in older adults?A 12-week double-blind randomized controlled trial

Introduction: Aging is associated with increased levels of circulating inflammatory markers and reduced muscle mass and strength. Objective: We investigated whether intake of protein-enriched milk for 12 weeks would influence markers of inflammation among adults ≥ 70 years of age with reduced physical strength. Methods: In a double-blind randomized controlled intervention study, subjects were randomly allocated into two groups, receiving a protein-enriched milk (2 x 20 g protein/d, n=14, mean (±SD) age 76.9 ± 4.9 yrs) or an isocaloric carbohydrate drink (n=17, age 77.7 ± 4.8 yrs) for 12 weeks. We measured serum and mRNA expression levels of inflammatory markers in PBMCs. Results: Significant differences in the mRNA expression of nuclear receptor subfamily, group H, member 3 (NR1H3, encoding the LXRα transcription factor) and interferon gamma (INFG) were observed between groups. The mRNA level of TNFRSF1A was significantly reduced, while the mRNA level of dipeptidyl-peptidase 4 (DPP4) was significantly increased, in the control group. The serum level of TNFα increased significantly in the control group, while sTNFRSF1A increased significantly in both groups, but with no significant differences between groups. Conclusion: Consumption of a low-fat, protein-enriched milk for 12 weeks had minor effects on inflammatory related markers in older adults compared to an isocaloric carbohydrate drink

The effect of increased protein intake on genome-wide gene expression in peripheral mononuclear cells of home-dwelling old subjects

Background Adequate protein intake among older adults is associated with better health outcomes such as immune function and metabolic regulation of skeletal muscle, but conflicting results make it difficult to define the optimal intake. To further understand the impact of protein intake on metabolic processes, the aim of the study was to explore genome-wide gene expression changes in peripheral blood mononuclear cells (PBMCs) in home-dwelling old subjects after increased protein intake for 12 weeks. Method In a parallel double-blind randomized controlled intervention study, subjects (≥ 70 years) received a protein-enriched milk (2 × 20 g protein/day, n = 14, mean (±SD) age 76.9 ± 4.9 years) or an isocaloric carbohydrate drink (n = 17, mean (±SD) age 77.7 ± 4.8 years) for breakfast and evening meal for 12 weeks. PBMCs were isolated before and after the intervention. Microarray analysis was performed using Illumina technology. Serum levels of gut peptides and insulin growth factor (IGF)-1 were also measured. Results In total 758 gene transcripts were regulated after increased protein intake, and 649 gene transcripts were regulated after intake of carbohydrates (p < 0.05). Forty-two of these genes were overlapping. After adjusting for multiple testing, 27 of the 758 gene transcripts were regulated (FDR, q-value < 0.25) after protein intake. Of these 25 were upregulated and two downregulated. In particular, genes and signaling pathways involved in pro-opiomelanocortin (POMC) processing, immune function, and IGF signaling were significantly altered. Conclusions PBMCs can be used to study gene expression changes after long-term protein intake, as many signaling pathways were regulated after increased protein intake. The functional significance of these findings needs to be further investigated

Dairy products influence gut hormone secretion and appetite differently: A randomized controlled crossover trial

Little is known about how dairy products with different nutrient contents and food matrices affect appetite sensation and gut hormone secretion. The objective of this study was to investigate how appetite sensation and gut hormone secretion in healthy adults are affected by meals with the same amount of fat but from different dairy products. Forty-seven healthy adults (70% women) were recruited to a randomized controlled crossover study with 4 dairy meals consisting of butter, cheese, whipped cream, or sour cream, corresponding to 45 g (approximately 60 energy percent) of fat. Plasma samples were collected for analysis of cholecystokinin (CCK), pancreatic polypeptide (PP), peptide YY (PYY), and ghrelin concentrations at 0, 2, 4, and 6 h after the meals and analyzed as the incremental area under the curve (iAUC0–6h) in a mixed model. Hunger, satiety, and appetite sensations were measured with a visual analog scale (VAS) immediately after finishing the meals and at 4 and 6 h postprandially. Intake of cheese induced a higher level of plasma PP-iAUC0–6h compared with butter or whipped cream, and a higher level of plasma CCK-iAUC0–6h compared with whipped cream. Intake of whipped cream increased VAS appetite at 4 h compared with cheese or sour cream, and at 6 h compared with cheese or butter. No significant meal effect was found for hunger, satiety, plasma PYY, or plasma ghrelin concentration. Intake of cheese increased postprandial plasma PP and CCK concentrations and decreased appetite compared with whipped cream but not with sour cream. These findings encourage further investigations of how different dairy products affect gut hormone secretion and appetite sensation

Meals with Similar Fat Content from Different Dairy Products Induce Different Postprandial Triglyceride Responses in Healthy Adults: A Randomized Controlled Cross-Over Trial

Postprandial lipemia is a risk factor for cardiovascular disease. Dairy products differ in nutrient content and food matrix, and little is known about how different dairy products affect postprandial triglyceride (TG) concentrations. We investigated the effect of meals with similar amounts of fat from different dairy products on postprandial TG concentrations over 6 h in healthy adults. A randomized controlled cross-over study was performed on 47 subjects (30% men), with median (25th–75th percentile) age of 32 (25–46) y and body mass index of 23.6 (21.0–25.8) kg/m2. Meals included 1 of butter, cheese, whipped cream, or sour cream, corresponding to 45 g of fat (approximately 60 energy%). Serum concentrations of TGs (primary outcome), and total cholesterol (TC), low density lipoprotein cholesterol (LDL cholesterol), high density lipoprotein cholesterol (HDL cholesterol), insulin, glucose, non-esterified fatty acids, and plasma glucose-dependent insulinotropic polypeptide (secondary outcomes) were measured before the meal and 2, 4, and 6 h postprandially. Incremental AUC (iAUC) was calculated for the responses, and data were analyzed using a linear mixed model. Sour cream induced a 61% larger TG-iAUC0–6 h compared to whipped cream (P &lt; 0.001), a 53% larger TG-iAUC0–6 h compared to butter (P &lt; 0.001), and a 23% larger TG-iAUC0–6 h compared to cheese (P = 0.05). No differences in TG-iAUC0–6 h between the other meals were observed. Intake of sour cream induced a larger HDL cholesterol-iAUC0–6 h compared to cheese (P = 0.01). Intake of cheese induced a 124% larger insulin iAUC0–6 h compared to butter (P = 0.006). No other meal effects were observed. High-fat meals containing similar amount of fat from different dairy products induce different postprandial effects on serum TGs, HDL cholesterol, and insulin in healthy adults. The potential mechanisms and clinical impact of our findings remain to be further elucidated. The study was registered at www.clinicaltrials.gov as NCT02836106