Eduardo Iglesias-Gutiérrez

Raising plasma fatty acid concentration induces increased biogenesis of mitochondria in skeletal muscle

A number of studies have reported that a high-fat diet induces increases in mitochondrial fatty acid oxidation enzymes in muscle. In contrast, in two recent studies raising plasma free fatty acids (FFA) resulted in a decrease in mitochondria. In this work, we reevaluated the effects of raising FFA on muscle mitochondrial biogenesis and capacity for fat oxidation. Rats were fed a high-fat diet and given daily injections of heparin to raise FFA. This treatment induced an increase in mitochondrial biogenesis in muscle, as evidenced by increases in mitochondrial enzymes of the fatty acid oxidation pathway, citrate cycle, and respiratory chain, with an increase in the capacity to oxidize fat, as well as an increase in mitochondrial DNA copy number. Raising FFA also resulted in an increase in binding of peroxisome proliferator-activated receptor (PPAR) δ to the PPAR response element on the carnitine palmitoyltransferase 1 promoter. We interpret our results as evidence that raising FFA induces an increase in mitochondrial biogenesis in muscle by activating PPARδ.

Tissue-specific control of mitochondrial respiration in obesity-related insulin resistance and diabetes

The tissue-specific role of mitochondrial respiratory capacity in the development of insulin resistance and type 2 diabetes is unclear. We determined mitochondrial function in glycolytic and oxidative skeletal muscle and liver from lean (+/?) and obese diabetic (db/db) mice. In lean mice, the mitochondrial respiration pattern differed between tissues. Tissue-specific mitochondrial profiles were then compared between lean and db/db mice. In liver, mitochondrial respiratory capacity and protein expression, including peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α), was decreased in db/db mice, consistent with increased mitochondrial fission. In glycolytic muscle, mitochondrial respiration, as well as protein and mRNA expression of mitochondrial markers, was increased in db/db mice, suggesting increased mitochondrial content and fatty acid oxidation capacity. In oxidative muscle, mitochondrial complex I function and PGC-1α and mitochondrial transcription factor A (TFAM) protein levels were decreased in db/db mice, along with increased level of proteins related to mitochondrial dynamics. In conclusion, mitochondrial respiratory performance is under the control of tissue-specific mechanisms and is not uniformly altered in response to obesity. Furthermore, insulin resistance in glycolytic skeletal muscle can be maintained by a mechanism independent of mitochondrial dysfunction. Conversely, insulin resistance in liver and oxidative skeletal muscle from db/db mice is coincident with mitochondrial dysfunction.

Circulating inflammatory miRNA signature in response to different doses of aerobic exercise.

While moderate acute exercise has been associated with strong anti-inflammatory mechanisms, strenuous exercise has been linked to deleterious inflammatory perturbations. It is therefore fundamental to elucidate the mechanisms that regulate the exercise-induced inflammatory cascade. Information on novel regulators such as circulating inflammatory microRNAs (c-inflammamiRs) is incomplete. In this study, we evaluated the response of a panel of c-inflammamiRs to different doses of acute aerobic exercise. We first studied the exercise-induced inflammatory cascade in serum samples of nine active middle-aged males immediately before and after (0 h, 24 h, 72 h) 10-km, half-marathon, and marathon races. Next, we analyzed the circulating profile of 106 specific c-inflammamiRs immediately before) and after (0 h, 24 h) 10-km (low inflammatory response) and marathon (high inflammatory response) races. Analysis of classical inflammatory parameters revealed a dose-dependent effect of aerobic exercise on systemic inflammation, with higher levels detected after marathon. We observed an increase in miR-150-5p immediately after the 10-km race. Levels of 12 c-inflammamiRs were increased immediately after the marathon (let-7d-3p, let-7f-2-3p, miR-125b-5p, miR-132-3p, miR-143-3p, miR-148a-3p, miR-223-3p, miR-223-5p, miR-29a-3p, miR-34a-5p, miR-424-3p, and miR-424-5p). c-inflammamiRs returned to basal levels after 24 h. Correlation and in silico analyses supported a close association between the observed c-inflammamiR pattern and regulation of the inflammatory process. In conclusion, we found that different doses of acute aerobic exercise induced a distinct and specific c-inflammamiR response, which may be associated with control of the exercise-induced inflammatory cascade. Our findings point to c-inflammamiRs as potential biomarkers of exercise-induced inflammation, and hence, exercise dose.

Docosahexaenoic Acid Modulates the Enterocyte Caco-2 Cell Expression of MicroRNAs Involved in Lipid Metabolism

Consumption of the long-chain ω-3 (n-3) polyunsaturated fatty acid docosahexaenoic acid (DHA) is associated with a reduced risk of cardiovascular disease and greater chemoprevention. However, the mechanisms underlying the biologic effects of DHA remain unknown. It is well known that microRNAs (miRNAs) are versatile regulators of gene expression. Therefore, we aimed to determine if the beneficial effects of DHA may be modulated in part through miRNAs. Loss of dicer 1 ribonuclease type III (DICER) in enterocyte Caco-2 cells supplemented with DHA suggested that several lipid metabolism genes are modulated by miRNAs. Analysis of miRNAs predicted to target these genes revealed several miRNA candidates that are differentially modulated by fatty acids. Among the miRNAs modulated by DHA were miR-192 and miR-30c. Overexpression of either miR-192 or miR-30c in enterocyte and hepatocyte cells suggested an effect on the expression of genes related to lipid metabolism, some of which were confirmed by endogenous inhibition of these miRNAs. Our results show in enterocytes that DHA exerts its biologic effect in part by regulating genes involved in lipid metabolism and cancer. Moreover, this response is mediated through miRNA activity. We validate novel targets of miR-30c and miR-192 related to lipid metabolism and cancer including nuclear receptor corepressor 2, isocitrate dehydrogenase 1, DICER, caveolin 1, ATP-binding cassette subfamily G (white) member 4, retinoic acid receptor β, and others. We also present evidence that in enterocytes DHA modulates the expression of regulatory factor X6 through these miRNAs. Alteration of miRNA levels by dietary components in support of their pharmacologic modulation might be valuable in adjunct therapy for dyslipidemia and other related diseases.

Nutrient Intake and Food Habits of Soccer Players: Analyzing the Correlates of Eating Practice

Despite the impact and popularity of soccer, and the growing field of soccer-related scientific research, little attention has been devoted to the nutritional intake and eating habits of soccer players. Moreover, the few studies that have addressed this issue suggest that the nutritional intake of soccer players is inadequate, underscoring the need for better adherence to nutritional recommendations and the development and implementation of nutrition education programs. The objective of these programs would be to promote healthy eating habits for male and female soccer players of all ages to optimize performance and provide health benefits that last beyond the end of a player’s career. To date, no well-designed nutrition education program has been implemented for soccer players. The design and implementation of such an intervention requires a priori knowledge of nutritional intake and other correlates of food selection, such as food preferences and the influence of field position on nutrient intake, as well as detailed analysis of nutritional intake on match days, on which little data is available. Our aim is to provide an up-to-date overview of the nutritional intake, eating habits, and correlates of eating practice of soccer players.

Circulating microRNAs in Huntington's disease: Emerging mediators in metabolic impairment.

Huntingtons disease (HD) is a hereditary neurodegenerative disease, with peripheral consequences that negatively contribute to quality of life. Circulating microRNAs (cmiRNAs) are being explored for their roles in intercellular communication and gene expression regulation, which allows gaining insight into the regulation of crosstalk between neuronal and peripheral tissues. Here, we explore the cmiRNA profile of plasma samples from fifteen symptomatic patients, with 40-45 CAG repeats in the HTT gene, and seven healthy matched controls. Isolated miRNAs from plasma samples were run against human miRNome panels, which have sequences for 752 human mature miRNAs. We found that 168 cmiRNAs are altered in symptomatic patients. Considering Bonferronis correction, miR-877-5p, miR-223-3p, miR-223-5p, miR-30d-5p, miR-128, miR-22-5p, miR-222-3p, miR-338-3p, miR-130b-3p, miR-425-5p, miR-628-3p, miR-361-5p, miR-942 are significantly increased in HD patients as compared with controls. Moreover, after patients organization according to approved HD scales, miR-122-5p is significantly decreased in HD patients with Unified Huntingtons Disease Rating Scale >24, whereas an increase in miR-100-5p levels and a decrease in miR-641 and miR-330-3p levels were recorded when patients were rearranged by Total Functional Capacity. These results suggest that cmiRNA profile could be further modified by disease progression, making cmiRNAs useful as monitoring biomarkers. Analysis of target genes indicated a general overexpression of cmiRNAs implicated in metabolism regulation. Profiling cmiRNA of HD subjects opens the possibility of personalized therapies for different groups of HD patients, based on disease modifiers: regulation of altered pathways might contribute to not only alleviate disease symptoms, but also influence HD progression.

Mother's nutritional miRNA legacy: Nutrition during pregnancy and its possible implications to develop cardiometabolic disease in later life.

Maternal nutrition during pregnancy and lactation influences the offsprings health in the long-term. Indeed, human epidemiological studies and animal model experiments suggest that either an excess or a deficit in maternal nutrition influence offspring development and susceptibility to metabolic disorders. Different epigenetic mechanisms may explain in part the way by which dietary factors in early critical developmental steps might be able to affect the susceptibility to develop metabolic diseases in adulthood. microRNAs are versatile regulators of gene expression and play a major role during tissue homeostasis and disease. Dietary factors have also been shown to modify microRNA expression. However, the role of microRNAs in fetal programming remains largely unstudied. This review evaluates in vivo studies conducted to analyze the effect of maternal diet on the modulation of the microRNA expression in the offspring and their influence to develop metabolic and cardiovascular disease in later life. In overall, the available evidence suggests that nutritional status during pregnancy influence offspring susceptibility to the development of cardiometabolic risk factors, partly through microRNA action. Thus, therapeutic modulation of microRNAs can open up new strategies to combat - later in life - the effects of nutritional insult during critical points of development.

Is there a relationship between the playing position of soccer players and their food and macronutrient intake

Many authors have proposed the necessity of the design and implementation of dietary and nutrition education programs for soccer players, although little information is available about the determinants of food selection and nutrient intake. The aim of this study was to evaluate the nutritional intake and eating patterns of soccer players according to their playing position in the team. Eighty-seven young male soccer players (aged 16-21 years) were recruited from the junior teams of a Spanish First Division Soccer League Club and divided into 6 positional categories (goalkeepers, full-backs, centre-backs, midfielders, wingers, and forwards). Body composition (height, weight, and body fat), performance in soccer-specific tests (jumping, sprinting, and intermittent endurance), and dietary intake (weighed food intake method) were assessed. A spontaneous higher carbohydrate intake was observed for full-backs, midfielders, and wingers (g·kg(-1) body mass: 4.9 ± 1.0, 4.9 ± 1.3, 4.9 ± 0.8; % of energy intake: 47 ± 5, 46 ± 6, 46 ± 4), compared with goalkeepers and centre-backs (g·kg(-1) of body mass: 3.9 ± 1.0, 4.3 ± 1.1; % of energy intake: 44 ± 3, 42 ± 4). These differences were related to food selection patterns, and a higher contribution to daily energy intake of cereals, derivatives, and potatoes was observed between full-backs compared with goalkeepers and centre-backs (33% vs. 27% and 25%). The magnitude of these differences is limited considering the whole diet, and an inadequate nutrient intake were observed in most individuals of every group. The design and implementation of nutrition intervention programs, taking into consideration positional differences in nutritional intake, would be useful for these players.

Epigenetic Biomarkers and Cardiovascular Disease: Circulating MicroRNAs

MicroRNAs (miRNAs) are a class of small noncoding RNA (20-25 nucleotides) involved in gene regulation. In recent years, miRNAs have emerged as a key epigenetic mechanism in the development and physiology of the cardiovascular system. These molecular species regulate basic functions in virtually all cell types, and are therefore directly associated with the pathophysiology of a large number of cardiovascular diseases. Since their relatively recent discovery in extracellular fluids, miRNAs have been studied as potential biomarkers of disease. A wide array of studies have proposed miRNAs as circulating biomarkers of different cardiovascular pathologies (eg, myocardial infarction, coronary heart disease, and heart failure, among others), which may have superior physicochemical and biochemical properties than the conventional protein indicators currently used in clinical practice. In the present review, we provide a brief introduction to the field of miRNAs, paying special attention to their potential clinical application. This includes their possible role as new diagnostic or prognostic biomarkers in cardiovascular disease.

Estimating Energy Requirements

Women energy requirements need be balance with total daily energy expenditure (TDEE). Hence, meeting of energy needs for all components of TDEE must be the most important concern for active females. Resting metabolic rate (RMR), thermic effect of food (TEF), and physical activity energy expenditure (PAEE) are the most important components of TDEE; where the most variable is the PAEE. The quantification of each component implies time consuming and expensive techniques, which are unviable in field and clinical settings. However, indirect methods have been developed to allow coaches, physicians, and nutritionists estimate TDEE. In this chapter, we cover the physiological relevance of RMR, TEF, and PAEE, and the indirect ways to obtain estimations of their values. On the other hand, other variables factors affecting TDEE as adaptive thermogenesis and non-exercise activity thermogenesis (NEAT) are highlighted. Finally, a case study is suggested in order to introduce basic metabolic calculations and physical activity level (PAL) concept.