Los servidores públicos judiciales y el nepotismo

Whilst exercise may mediate changes in GI function and contribute to subjective symptom expression its combination with pharmaceutical agents and its clinical impact on the gut has come to prominence as an increasing problem (McAnulty et al., 2007; Nieman, et al., 2006; Sanabria & Zabala, 2017;Tscholl & Dvorak, 2012). Nonsteroidal anti-inflammatory drugs (NASIDs) are widely available over the counter agents used in the acute and chronic treatment and management of soft-tissue injuries and for analgesic purposes (Tscholl et al., 2016). It is generally assumed, incorrectly, that the use of NSAIDs can help performance due to their facilitation of more frequent, intense training sessions by acting to mask adverse musculoskeletal issues; therefore, they are regularly used by athletes in a variety of sports (Alaranta et al., 2008; Gorski et al., 2011; Tscholl & Dvorak, 2012). The high prevalence rates for NSAID consumption particularly from a prophylactic perspective is often accompanied by limited awareness of the side effects of use particularly on a chronic basis (Didier et al., 2017; Gorski et al., 2011; Warden, 2009). Several reports on the use of NSAID medication across team sports has indicated an unexpectedly high level of both prescribed and un-prescribed consumption of NSAIDs (Holgado et al., 2017; Tscholl & Dvorak, 2012; Tscholl et al., 2015). Due to NSAIDs analgesic, anti-inflammatory and antipyretic effects, they have evolved into one of the most commonly used class of pharmaceutical agent by athletes to ameliorate a range of musculoskeletal pathologies including post exercise muscle soreness (Da Silva et al., 2015; Holgado et al., 2017; Vaso et al., 2015). Clinically, NSAID

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induced GI mucosal damage in the form of mucosal erosion and ulceration is a well described adverse effect of their usage (Marlicz et al., 2014). Significantly, NSAIDs such as ibuprofen have previously been found to increase gastrointestinal GI permeability at rest (Blackler et al., 2014; Sostres et al., 2017) and following exercise particularly after prolonged, sub-maximal endurance events such as marathon and triathlons (Jeukendrup et al., 2000; Küster et al., 2013; McAnulty et al., 2007; Nieman et al., 2006; Smetanka et al., 1999; Whatmough et al., 2017). NSAID [Ibuprofen] induced complications are thought to be caused as a result of the inhibition of cyclooxygenase (COX) isotypes 1 and 2 and in particular (COX-2), via a reduction in localised nitric oxide (NO) production and inhibition of prostaglandin release (Vieth & Montgomery, 2017). These responses to NSAID ingestion can cause an inflammatory response of the GI barrier and may impair perfusion of the upper GI tract (Holgado et al., 2017; Lambert et al., 2007; Lanas et al., 2003). Such modifications altering mucosal cytoskeleton integrity and causing GI damage, permeability and necrosis (Vieth & Montgomery, 2017).

Since the use of NSAIDs in a variety of sports and individual events is widespread, the effect they have on the GI barrier function alone or when combined with exercise (predominately endurance exercise) have been subject to limited review. Given NSAIDs widespread use amongst invasion field sports such data would provide insight into potential adverse effects on GI function (Tscholl & Dvorak, 2012; Vaso et al., 2015). Lambert et al. (2001) report increased gastroduodenal and intestinal permeability after ingesting 1,300 mg of aspirin prior to 60 minutes of running at 70% V̇O2max. Lambert et al. (2007) further reported different responses between aspirin and ibuprofen, with aspirin increasing intestinal permeability relative to ibuprofen again following steady state running. Aspirin effects the COX-1 pathway, which is involved with synthesis of the mucosa and ibuprofen predominately effects the COX-2 pathway, which is involved with inflammation (Iwamoto et al., 2013). van Wijck et al. (2012) have reported increased GI permeability and damage after one hour of moderate intensity exercise following acute NSAID ingestion. Such data inform the view that NSAIDS are known to accentuate GI injury particularly under physical stress (Audet et al., 2016) and have also been shown to mediate lethality between NSAIDS, hyperthermia and/or exercise in rodents; although to date this has not been reported in humans (Takahashi et al., 2001; Audet et al., 2017).

50 2.14 Summary of literature.

It is apparent from the proceeding literature that the coincidence of exercise, environmental challenge and variations in both the duration and intensity of exercise leading to perturbations in GI perfusion may predispose the gastrointestinal system to adverse changes notably in its ability to partition the content of GI lumen from systemic circulation. Epidemiological data clearly report increased symptomology of gastrointestinal disturbance (nausea, vomiting, diarrhoea cramps and bloating) in both male and female runners and athletes, with symptomology perhaps increasing as a function of exercise modality, distance run, and gender (Peters et al., 1999; van Nieuwenhoven et al., 2004; ter Steege et al., 2008). Mechanistic links between the presentation of the gastro-intestinal symptoms, the exercise challenge, and disruption to gut mucosa have been ascribed to reductions in gastrointestinal blood flow due to vasoconstriction of splanchnic vasculature (ter Steege et al., 2012). This redistribution of cardiac output away from the splanchnic vasculature to active skeletal muscle in order to maintain exercise activity is proportional to the increase in exercise intensity. As such splanchnic blood flow may be reduced by up to 80% of resting blood flow, leading to gastro-intestinal ischemia, transient hypoxia and oxidative and nitrosative stress for as long as exercise stress is maintained. A further corollary of the increase in exercise intensity is a progressive hyperthermia (Lim and Mackinnon, 2006; Gonzalez-Alonso et al., 2008; Selkirk et al., 2008). Increased thermal strain from both the exercise itself and exercise undertaken in different environmental temperatures (Lim and Mackinnon, 2006; Gonzalez-Alonso et al., 2008; Selkirk et al., 2008) and in different exercise models (Yano et al., 2002; Lambert, 2004; Lambert, 2008) may also be contributory to GI damage. The alteration GI permeability and damage in hyperthermia conditions being characterised as subject to a threshold effect (Pires et al., 2016). Several recent models have summarised this conceptual framework (Figure 2.6). Determination of the effects of the interaction between intensity and modality of exercise on GI function remains to be fully elucidated.

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