Insulin resistance is central to the pathogenesis of non-alcoholic fatty liver disease (NAFLD) and type 2 diabetes mellitus (T2DM). Intrahepatic triglyceride (IHTG), the primary feature of NAFLD, strongly predicts insulin resistance in the liver and peripheral (skeletal muscle and adipose) tissues. Hepatokines (e.g. fibroblast growth factor 21 (FGF21), leukocyte cell-derived chemotaxin 2 (LECT2), follistatin, selenoprotein P, and fetuin-A) are liver-derived proteins with capacity to exert endocrine effects and may potentially modulate the link between IHTG and peripheral insulin sensitivity/glycaemic control. Exercise is integral to the management of NAFLD and T2DM, with evidence suggesting that high-intensity exercise may provide the greatest benefits. Chapter 4 of this thesis demonstrates that, in individuals without chronic metabolic disease, plasma concentrations of FGF21 and LECT2 are higher, and follistatin lower, in individuals with overweight or obesity compared with normal weight individuals. Furthermore, FGF21 and follistatin are transiently elevated for up to 6 h after acute aerobic exercise (60 min at 60% V̇O2 peak). The response of follistatin to acute moderate-intensity exercise is also present in individuals with impaired glucose regulation (Chapter 5), but the response of FGF21 is abolished. A single bout of low-volume high-intensity interval training has no effect on FGF21, follistatin or fetuin-A in individuals with dysglycaemia (Chapter 5). Chapter 6 demonstrates that six weeks of sprint interval training (SIT) is feasible for men with NAFLD and reduces IHTG despite no change in body weight. Peripheral insulin sensitivity tends to increase after SIT but hepatic insulin sensitivity and circulating hepatokines remain unchanged. Through meta-analyses, Chapter 7 confirms that exercise training reduces IHTG, even in the absence of weight loss. However, the magnitude of this effect is greater when weight loss occurs and benefits increase proportionally. Exercise training improves basal hepatic insulin sensitivity, but evidence in this area is currently limited (Chapter 7). Collectively, the studies in this thesis demonstrate that some hepatokines may be sensitive to acute and chronic changes in energy metabolism. However, further evidence is required before definitive statements can be made. Exercise training, including SIT, has the potential to reduce IHTG in men with NAFLD, even in the absence of weight loss. However, the greatest benefits on IHTG will likely be elicited when exercise training is performed in combination with dietary energy restriction to elicit sustained reduction in body weight.

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No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Dissertação-Fernando Augusto Fernades Corrêa-2013.pdf: 1051896 bytes, checksum: ce6c70a518ef78aa9fec8f6e948033cd (MD5) Previous issue date: 2013-11-26 / Therefore the study aimed to investigate the presence of these bacteria in edible offal, feathers and poultry litter. Relate the presence of these bacteria in different scores macroscopic changes and determine the sensitivity of E. coli and Staphylococcus antimicrobials of importance in veterinary medicine. For it was collected 13 samples of manure directly in the sheds, abattoir were collected in 12 lots of feathers, plucking directly into 12 lots of heart and liver, the inspection line, totaling 740 samples 740 samples of heart and liver. We established three scores for injuries to the heart and six for the liver. From these samples was carried out the isolation of the bacteria E. coli, coagulase positive Staphylococcus, Pseudomonas spp. and Salmonella sp.. Positive for E. coli and Staphylococcus co were tested for sensitivity to the following antibiotics: ciprofloxacin (5 mg), ceftiofur (25 mg), chloramphenicol (30 mg), erythromycin (15 mg) , tetracycline (30 mg) , trimethoprim-sulfamethoxazole (25 mg) , enrofloxacin (5 mg), oxacillin (1 mg) and gentamycin (10 mg). In addition to those for E. coli was also used colistin (20 mg) and Staphylococcus coagulase positive bacitracin (10 mg). In any sample analyzed was identified Salmonella sp. were found in hearts, 33.1%, 6.6% and 28.2% of E. coli, coagulase positive Staphylococcus and Pseudomonas spp. respectively. In livers 45.4%, 8.0% and 23.1% of E. coli, coagulase positive Staphylococcus and Pseudomonas spp. respectively. To feather the results were 29.2%, 16.7% and 35.8% of E. coli, coagulase positive Staphylococcus and Pseudomonas spp. respectively. In the samples of poultry litter was not isolating Staphylococcus isolates of E. coli and Pseudomonas spp. were 92.3% and 7.7% respectively. In antimicrobial susceptibility testing on samples of E. coli and Staphylococcus coagulase positive bacteria showed the following percentage of antimicrobial susceptibility respectively: ciprofloxacin (36.7% and 58.8%), ceftiofur (8.1% and 64.7%), chloramphenicol (81.0% and 76.5%), erythromycin (2.9% and 41.2%), tetracycline (30.9% and 41.2%), Trimethoprim -sulfamethoxazole (43.8% and 82.3%), enrofloxacin (18.6% and 47.1%), oxacillin (3.8% and 47.1%) and gentamicin (37.1% and 64.7%). For isolates of E. coli tested for sensitivity to colistin 96.7% were sensitive. And for Staphylococcus tested for sensitivity to bacitracin, no specimens were susceptible to this antimicrobial agent. / O trabalho teve como objetivo investigar a presença de bactérias (Escherichia coli, Staphylococcus coagulase positiva, Pseudomonas spp. e Salmonella sp.) em vísceras comestíveis, penas e cama de frango. Bem como relacionar a presença destas bactérias em diferentes escores de alterações macroscópicas e determinar o perfil de sensibilidade de E. coli e Staphylococcus a antimicrobianos de importância em medicina veterinária. Para isso foram coletados 13 amostras de cama de aviário diretamente nos galpões. No abatedouro frigorífico foram coletados 12 lotes de penas, diretamente na depenadeira, 12 lotes de coração e fígado, na linha de inspeção, totalizando 740 amostras de coração e 740 amostras de fígado. Foram estabelecidos três escores de lesões para o coração e seis para o fígado. A partir destas amostras foi realizado o isolamento das bactérias E. coli, Staphylococcus coagulase positiva, Pseudomonas spp e Salmonela sp.. Os positivos para E. coli e Staphylococcus foram submetidos ao teste de sensibilidade aos seguintes antimicrobianos: ciprofloxacina (5 mg), ceftiofur (25 mg), clorafenicol (30 mg), eritromicina (15 mg), tetraciclina (30 mg), Sulfametoxazol-Trimetroprim (25 mg), enrofloxacina (5 μg), oxacilina (1 mg) e gentamicina (10 mg). Além destes para E. coli também foi utilizado colistina (20 mg) e para Staphylococcus coagulase positiva bacitracina (10 μg). Em nenhuma amostra analisada foi identificado Salmonella sp.. Foram encontrados em corações, 33,1%, 6,6% e 28,2% de E. coli, Staphylococcus coagulase positiva e Pseudomonas spp. respectivamente. Em fígados 45,4%, 8,0% e 23,1% de E. coli, Staphylococcus coagulase positiva e Pseudomonas spp. respectivamente. Para penas os resultados encontrados foram de 29,2%, 16,7% e 35,8% de E. coli, Staphylococcus coagulase positiva e Pseudomonas spp. respectivamente. Nas amostras de cama de frango não ocorreu isolamento de Staphylococcus, os isolados de E. coli e Pseudomonas spp. foram 92,3% e 7,7% respectivamente. No teste de sensibilidade a antimicrobianos nas amostras de E. coli e Staphylococcus coagulase positiva, as bactérias apresentaram a seguinte porcentagem de suscetibilidade aos antimicrobianos respectivamente: ciprofloxacina (36,7% e 58,8%), ceftiofur (8,1% e 64,7%), clorafenicol (81,0% e 76,5%), eritromicina (2,9% e 41,2%), tetraciclina (30,9% e 41,2%), Sulfametoxazol-Trimetroprim (43,8% e 82,3%), enrofloxacina (18,6% e 47,1%), oxacilina (3,8% e 47,1%) e gentamicina (37,1% e 64,7%). Para os isolados de E. coli submetidos ao teste de sensibilidade à colistina 96,7% foram sensíveis. E para os isolados de Staphylococcus submetidos ao teste de sensibilidade a bacitracina, nenhuma amostra foi suscetível a este antimicrobiano.