1,721,104 research outputs found
Physical exercise and suppression of autoimmunity in type 1 diabetes. C-Peptide and the pathophysiology of diabetes – an update
No full textFor decades it has been known that regular aerobic exercise improves insulin sensitivity in diabetic patients, reducing insulin requirements. Traditionally, physical exercise has been promoted in Type 2 Diabetes, where insulin action is deficient in the context of insulin resistance and/or inappropriate insulin secretion. However, even in Type 1 Diabetes Mellitus (T1DM), in the dysregulation of immune system function, beta-cell toxicity is mediated by a complex interplay between oxidative stress and inflammation, for which exercise could be protective. Here, we collected immunological and metabolic data in T1DM patients (n=12, male, ± yrs) to understand whether exercise can favourably affect autoimmunity. A regression results analysis showed an inverse relationship between autoimmunity markers (GAD, IA) and weekly energy expenditure derived from physical exercise [Fig.1]. In another extensive analysis we found that regularly exercising T1DM-subjects have prolonged “honeymoon”, the early stage of the disease in which insulin requirements are latently lower than in advanced T1DM. These preliminary observations suggest that physical exercise may interfere with immune system function, even at low intensity and duration. Given its powerful ability to modulate oxidative stress and mitigate chronic inflammatory conditions, like those leading to autoimmunity diseases, we are going to design an exercise training program counteracting the autoimmune response which, in T1DM, attacks and destroys the insulin producing cells. Exercise emerges as a safe therapy against T1DM
Boiling factors in the pot of type 1 diabetes mellitus management: the role of exercise
Full text linkPerceptual-cognitive processes in sport: the role of the sports task on quiet eye
Full text linkThe present doctoral thesis dealt with a relevant perceptual-cognitive factor within the sports domain, called "quiet eye" (QE). The literature on this topic described the QE as an ocular fixation that could be considered a hallmark of superior expertise and performances across several sports requiring aiming tasks. Indeed, several characteristics of the QE (e.g., earlier onset and a longer quiet eye duration) correlate with greater athletes' expertise and best performances. In addition, QE training positively affects task performance.
Despite 25 years of research on QE, there is still no agreement about the QE function that could explain the relationship between this fixation and the highest levels of sports expertise and performance.
On this basis, the present doctoral thesis aimed to comprehend, through four different studies, the QE underlying functions by exploring novel aiming tasks and manipulating well-known sports tasks in the QE literature.
On the whole, the findings of the four studies suggest that the acquisition of environmental visual information through the QE occurs at different times during the ongoing action, according to the kinematical and timing specificity of the task. Therefore, the difference in QE timing between tasks should represent a different underlying function.
The results reported in the present doctoral thesis seem consistent with the speculation of Lebeau et al. (2016), who suggested that the specific role of the QE could depend on the type of sports task.
Besides the research value, the findings of the present doctoral thesis have important implications from an applied point of view. The literature showed that QE training protocols permit novices the acquisition of a "like an expert" gaze behavior. On the one hand, the results of the present doctoral thesis stretched the relevance of establishing a QE prototype specific to the task before implementing any QE training protocols to non-experts, following Vickers's (2016) guidelines. On the other hand, the results reported suggest that the QE training protocols should also be applied to expert athletes to permit the transfer of the QE characteristics to complex game conditions, allowing athletes to perform successfully, regardless of the trickiness of the sport situation
La stimolazione di forza nel diabetico di tipo 2
No full textPhysical exercise, along with diet and drug therapy, is one of the three cornerstones of the treatment and therapy for type 2 diabetes. The advantages of regular physical activity used therapeutically is enhanced by its non-drug nature, its beneficial effects on the metabolic risk factors associated with the complications of diabetes, and its low cost.
According to evidence collected in recent years, aerobical endurance exercise is a safe, feasible and effective mode of intervention in the treatment of type 2 diabetes, thanks to its insulin-sensitizing effects, also in relation to survival. Intense physical exercise, i.e. the anaerobic one, which is typical of force or power disciplines, is not unambiguously deemed so safe and easily implementable as the aerobic one, however, it is equally important to the purpose of stimulating stimulate energy - and glucose in particular - metabolisms.
The captioned research resumes the latest indications emerging from extensive literature which supports the beneficial effects of strength and muscle condtioning stimulation for type 2 diabetics, as far as there is no medical contraindication
Il metabolismo energetico muscolare nei soggetti sani, nei diabetici di tipo 2 e negli atleti
No full textL’esercizio fisico, insieme alla dieta e alla terapia farmacologica, rappresenta una delle tre pietre miliari nel trattamento e nella cura del diabete mellito di tipo 2. La sua natura non farmacologica, gli effetti benèfici sui fattori di rischio metabolico associati alle complicanze del diabete, e suoi bassi costi, contribuiscono ad aumentare l’“appeal terapeutico” della regolare attività fisica. Interminabile è la lista di studi che dimostra come l’esercizio aumenti il consumo di glucosio a livello periferico e sistemico, migliori la sensibilità insulinica, e consenta di raggiungere posizioni più fisiologicamente accettabili sulla nota curva iperbolica della glucose tolerance. L’esercizio fisico, infatti, è in grado di attivare acutamente il metabolismo del glucosio. Programmi d’allenamento ad hoc sono efficaci nello stimolare l’azione insulinica nell’organismo in toto in pazienti insulino-resistenti. Le evidenze accumulate in questi ultimi anni suggeriscono che l’esercizio fisico aerobico, d’endurance, costituisce una modalità di intervento sicura, realizzabile ed efficace nel trattamento del diabete anche in riferimento alla sopravvivenza. L’esercizio fisico intenso, anaerobico, come quello delle discipline di forza o di potenza, non è altrettanto univocamente riconosciuto come sicuro e semplice da realizzare, ma non meno importante nello stimolare il metabolismo energetico e del glucosio in particolare. La presente disamina contempla questi aspetti, valutando le risposte indotte dalla stimolazione fisica (acuta e cronica) in tre modelli esemplificativi per la comprensione del metabolismo del glucosio: il soggetto in cui tale metabolismo è fisiologicamente funzionante (sano), quello in cui è patologico o scompensato (diabete di tipo 2 e insulino-resistenza) ed infine quello in cui è massimamente vantaggioso per il turn-over dei substrati energetici, ovvero quello dei professionisti sportivi, gli atleti
Mitochondrial and Non-mitochondrial studies of ATP Synthesis
No full textEnergy is required to perform any kind of mechanical work. In living organisms, the energy for all biological functions is provided chemically by the hydrolysis of adenosine triphosphate (ATP). ATP supplies the energy required to synthesize cellular components and to maintain cell viability, by donating one or two phosphate groups, leaving adenosine diphosphate (ADP) or adenosine monophosphate (AMP), respectively. However, energy storage in the form of ATP is limited such that ATP must be resynthesized continuously in order to meet cellular energy demands. The generation or replenishment of ATP depends upon key metabolic pathways, glycolysis, glycogenolysis, and oxidative phosphorylation, which interact to regulate the rate of ATP metabolism and to direct cellular bioenergetics toward a defined homeostasis
Attività fisica nella terza e quarta età
No full textThe old age represents a virtual phase in anybody’s life characterized by a relative degree of physical declining so that a customized dose of physical activity is required. A cohesive literature has shown the essential need of a dynamic lifestyle for adults aged 65 years or above, for which physical activity is a shield against functional decline and the related chronic diseases. As lifespan increases, counteracting physical inactivity by means of exercise programs tailored on individual habits is obvious to abate healthcare expenses in a non-pharmachological way
In vivo magnetic resonance studies of muscle mitochondrial function in transgenic mice
No full textAlterations in muscle mitochondrial function have been implicated in the pathogenesis of numerous metabolic disorders, including insulin resistance, type 2 diabetes, obesity, and the deleterious effects of aging. However, the precise role for mitochondrial function in these processes remains to be established. In vivo 31P Magnetic Resonance Spectroscopy (31P-MRS) is an effective technique that permits the non-invasive investigation of skeletal muscle metabolism and transgenic mice are a novel tool for examining the effects of specific genes on mitochondrial function. Combining these two approaches would be a powerful methodology for studying mitochondrial function but its implementation has been limited due to the small volume of muscle from which the MR signal can be obtained and the requirement that the region of interest (ROI) must remain still for the entire duration of these lengthy studies.
A new MR-compatible experimental set-up was developed to perform these experiments under low-dose anesthesia to minimize movement with constant physiological monitoring to ensure that the animal remained viable throughout the study. The unidirectional flux of ATP synthesis (Pi → ATP) was measured using 31P saturation-transfer MRS in two different transgenic mouse models overexpressing PGC-1α or UCP3. While PGC-1α has been shown to be a potent promoter of mitochondrial biogenesis and fiber-type remodelling, UCP3 seems to play a critical role in regulating mitochondrial activity, but, whether this might be its primary role is still a matter of debate. The rates of ATP production (VATP) were 19% lower in UCP3 +/+ mice with respect to their wild-type (WT) littermates (P=0.02) accompanied by a significant increase in energy expenditure and food intake, confirming a contributing role played by this protein in regulating mitochondrial energy production. In PGC-1α +/+ mice, VATP was increased in mice fed a regular chow (by 50%, P<0.01) or a high fat diet (by 58%, P<0.001) with respect to wild-type littermate mice, with no significant difference in energy expenditure, food intake or locomotor activity. In the mouse model overexpressing PGC-1α, higher rates of VATP suggest enhanced efficiency in ATP production.
This thesis has demonstrated that 31P-MRS can successfully be applied to the investigation of muscle mitochondrial function in transgenic mice in vivo
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