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Identified metabolites altered with the periodic practice of running on a treadmill at diverse intensities.

<p>The abundance values for each metabolite were transformed to a base-2 logarithm, normalized by the internal standard, and baselined to the mean of all samples. The data are given as the mean ± SEM (n = 9–12). To avoid the occurrence of false positives, a primary screen was carried out using two-way ANOVA and adjusting the p-value of the exercise parameter using the Benjamini-Hochberg correction. To more exhaustively evaluate the differences among groups, a posterior analysis without a p-value correction was performed. <i>E</i>: the effect of exercise; <i>D</i>: the effect of diet; <i>DxE</i>: the interaction between the two factors (two-way ANOVA, p<0.05). ^abcMean normalized values with different small letters were significantly different (one-way ANOVA and Tukey/Dunnett’s T3 <i>post hoc</i> contrast, p<0.05). Abbreviations: Lyso-PE, lysophosphatidylethanolamine; PG, phosphatidylglycerol; DiHETE, dihydroxy-eicosatetraenoic acid.</p

Impact of a cafeteria diet and daily physical training on the rat serum metabolome

<div><p>Regular physical activity and healthy dietary patterns are commonly recommended for the prevention and treatment of metabolic syndrome (MetS), which is diagnosed at an alarmingly increasing rate, especially among adolescents. Nevertheless, little is known regarding the relevance of physical exercise on the modulation of the metabolome in healthy people and those with MetS. We have previously shown that treadmill exercise ameliorated different symptoms of MetS. The aim of this study was to investigate the impact of a MetS-inducing diet and different intensities of aerobic training on the overall serum metabolome of adolescent rats. For 8 weeks, young rats were fed either standard chow (ST) or cafeteria diet (CAF) and were subjected to a daily program of training on a treadmill at different speeds. Non-targeted metabolomics was used to identify changes in circulating metabolites, and a combination of multivariate analysis techniques was implemented to achieve a holistic understanding of the metabolome. Among all the identified circulating metabolites influenced by CAF, lysophosphatidylcholines were the most represented family. Serum sphingolipids, bile acids, acylcarnitines, unsaturated fatty acids and vitamin E and A derivatives also changed significantly in CAF-fed rats. These findings suggest that an enduring systemic inflammatory state is induced by CAF. The impact of physical training on the metabolome was less striking than the impact of diet and mainly altered circulating bile acids and glycerophospholipids. Furthermore, the serum levels of monocyte chemoattractant protein-1 were increased in CAF-fed rats, and C-reactive protein was decreased in trained groups. The leptin/adiponectin ratio, a useful marker of MetS, was increased in CAF groups, but decreased in proportion to training intensity. Multivariate analysis revealed that ST-fed animals were more susceptible to exercise-induced changes in metabolites than animals with MetS, in which moderate-intensity seems more effective than high-intensity training. Our results indicate that CAF has a strong negative impact on the metabolome of animals that is difficult to reverse by daily exercise.</p></div

Additional file 1: of Changes in lysophospholipids and liver status after weight loss: the RESMENA study

Figure S1. Flowchart of participants. AHA, American Heart Association; RESMENA, metabolic syndrome reduction in Navarra; FLI, Fatty Liver Index. (DOCX 30 kb

Venn diagrams showing the number of significant entities from each experimental parameter.

<p>Data from each ionization mode, positive and negative, were analysed using two-way ANOVA. To handle false discovery rates from multiple comparisons, the cut-off point for significance was calculated according to the Benjamini-Hochberg correction at a level of 5%. <i>D</i>: the effect of diet; <i>E</i>: the effect of exercise; <i>DxE</i>: the interaction between the two main factors. The areas where the circles overlap show the number of significant entities shared by the parameters.</p

Table_3_The Exposure to Different Photoperiods Strongly Modulates the Glucose and Lipid Metabolisms of Normoweight Fischer 344 Rats.doc

<p>Seasonal variations in day length trigger clear changes in the behavior, growth, food intake, and reproductive status of photoperiod-sensitive animals, such as Fischer 344 rats. However, there is little information about the effects of seasonal fluctuations in day length on glucose and lipid metabolisms and their underlying mechanisms in this model. To gain knowledge on these issues, three groups of male Fischer 344 rats were fed with a standard diet and exposed to different photoperiods for 14 weeks: normal photoperiod (L12, 12 h light/day), long photoperiod (L18, 18 h light/day), and short photoperiod (L6, 6 h light/day). A multivariate analysis carried out with 239 biometric, serum, hepatic and skeletal muscle parameters revealed a clear separation among the three groups. Compared with L12 rats, L6 animals displayed a marked alteration of glucose homeostasis and fatty acid uptake and oxidation, which were evidenced by the following observations: (1) increased circulating levels of glucose and non-esterified fatty acids; (2) a sharp down-regulation of the phosphorylated Akt2 levels, a downstream post-receptor target of insulin, in both the soleus and gastrocnemius muscles; (3) decreased expression in the soleus muscle of the glucose metabolism-related microRNA-194 and lower mRNA levels of the genes involved in glucose metabolism (Irs1, soleus, and Glut2, liver), β-oxidation (Had and Cpt1β, soleus) and fatty acid transport (Cd36, soleus, and liver). L18 animals also displayed higher blood glucose levels than L12 rats and profound changes in other glucose and lipid metabolism-related parameters in the blood, liver, and skeletal muscles. However, the mechanisms that account for the observed effects were less evident than those reported in L6 animals. In conclusion, exposure to different photoperiods strongly modulated glucose and lipid metabolisms in normoweight rats. These findings emphasize the relevance of circannual rhythms in metabolic homeostasis regulation and suggest that Fischer 344 rats are a promising animal model with which to study glucose- and lipid-related pathologies that are influenced by seasonal variations, such as obesity, cardiovascular disease and seasonal affective disorder.</p

Circulating levels of hormones associated with lifestyle-related diseases.

<p>Animals were fed standard chow (ST) or cafeteria diet (CAF) for 2 months and periodically trained on a treadmill at different intensities (CON: 0; TML: 12; TMH: 17 m/min). The serum levels of adiponectin, leptin and irisin were determined at the end of the experiment after 12 h of fasting. The data are given as the mean ± SEM (n = 9–12). The statistical comparison among groups was conducted using two- and one-way ANOVA. <i>D</i>: the effect of diet; <i>E</i>: the effect of exercise. ^abcMean values with different small letters were significantly different (one-way ANOVA and Tukey/ Dunnett’s T3 <i>post hoc</i> contrast, p<0.05).</p

Table_2_The Exposure to Different Photoperiods Strongly Modulates the Glucose and Lipid Metabolisms of Normoweight Fischer 344 Rats.doc

<p>Seasonal variations in day length trigger clear changes in the behavior, growth, food intake, and reproductive status of photoperiod-sensitive animals, such as Fischer 344 rats. However, there is little information about the effects of seasonal fluctuations in day length on glucose and lipid metabolisms and their underlying mechanisms in this model. To gain knowledge on these issues, three groups of male Fischer 344 rats were fed with a standard diet and exposed to different photoperiods for 14 weeks: normal photoperiod (L12, 12 h light/day), long photoperiod (L18, 18 h light/day), and short photoperiod (L6, 6 h light/day). A multivariate analysis carried out with 239 biometric, serum, hepatic and skeletal muscle parameters revealed a clear separation among the three groups. Compared with L12 rats, L6 animals displayed a marked alteration of glucose homeostasis and fatty acid uptake and oxidation, which were evidenced by the following observations: (1) increased circulating levels of glucose and non-esterified fatty acids; (2) a sharp down-regulation of the phosphorylated Akt2 levels, a downstream post-receptor target of insulin, in both the soleus and gastrocnemius muscles; (3) decreased expression in the soleus muscle of the glucose metabolism-related microRNA-194 and lower mRNA levels of the genes involved in glucose metabolism (Irs1, soleus, and Glut2, liver), β-oxidation (Had and Cpt1β, soleus) and fatty acid transport (Cd36, soleus, and liver). L18 animals also displayed higher blood glucose levels than L12 rats and profound changes in other glucose and lipid metabolism-related parameters in the blood, liver, and skeletal muscles. However, the mechanisms that account for the observed effects were less evident than those reported in L6 animals. In conclusion, exposure to different photoperiods strongly modulated glucose and lipid metabolisms in normoweight rats. These findings emphasize the relevance of circannual rhythms in metabolic homeostasis regulation and suggest that Fischer 344 rats are a promising animal model with which to study glucose- and lipid-related pathologies that are influenced by seasonal variations, such as obesity, cardiovascular disease and seasonal affective disorder.</p

Dyslipidemic parameters.

<p>Animals were distributed into 6 groups (n = 9–12) based on diet and training condition: control-standard diet (CON-ST), treadmill-low intensity-standard diet (TML-ST), treadmill-high intensity-standard diet (TMH-ST), control-cafeteria diet (CON-CAF), treadmill-low intensity-cafeteria diet (TML-CAF) and treadmill-high intensity-cafeteria diet (TMH-CAF). Diets and training sessions started after the weaning period and were extended for 8 weeks. Lipid serum concentrations were determined at the end of the experiment after 12 h of fasting. The data are given as the mean ± SEM. The statistical comparison among groups was conducted using two- and one-way ANOVA. <i>D</i>: the effect of diet; <i>E</i>: the effect of exercise; <i>DxE</i>: the interaction between the two main factors. ^abcMean values with different small letters indicate significant differences between groups (one-way ANOVA and Dunnett’s T3 <i>post hoc</i> contrast, p<0.05).</p

Multivariate analysis demonstrating the effect of diet and physical exercise on the animal metabolome.

<p>Serum extracts were analysed using LC-ESI-MS in both positive and negative ionization modes. (A, D) Heat map representations of hierarchical clustering of significant entities found in each group of animals. Each row represents an exact mass coloured by its abundance intensity, normalized to an internal standard and baselined to the mean of all samples. The scale from -10 (blue) to +10 (red) represents this normalized abundance in arbitrary units. The PCA (B, E) and PLS-DA (C, F) graphs show that the effect of cafeteria diet had prevalence over the periodic training on the treadmill at diverse intensities. Abbreviations: ST, standard chow; CAF, cafeteria diet; CON, control animals; TML, treadmill-low intensity runners; TMH, treadmill-high intensity runners.</p