RESVERATROL ATTENUATES EXERCISE-INDUCED ADAPTIVE RESPONSES IN RATS SELECTIVELY BRED FOR LOW RUNNING PERFORMANCE

Low capacity runner (LCR) rats have been developed by divergent artificial selection for treadmill endurance capacity to explore an aerobic biology-disease connection. The beneficial effects of resveratrol supplementation have been demonstrated in endurance running. In this study it was examined whether 12 weeks of treadmill exercise training and/or resveratrol can retrieve the low running performance of the LCR and impact mitochondrial biogenesis and quality control. Resveratrol regressed running performance in trained LCR (p\u3c0.05). Surprisingly, exercise and resveratrol treatments significantly decreased pAMPK/AMPK, SIRT1, SIRT4, forkhead transcription factor 1 (FOXO1) and mitochondrial transcription factor A (TFAM) levels in these animals (p\u3c0.05). Mitochondrial fusion protein, HSP78 and polynucleotide phosphorylase were significantly induced in LCR-trained, LCR-resveratrol treated, LCR-trained and resveratol treated groups compared to LCR-controls. The data indicate that the AMPK-SIRT1-NAMPTFOXO1 axis could be important to the limited aerobic endurance capacity of low running capacity rats. Resveratrol supplementation was not beneficial in terms of aerobic endurance performance, mitochondrial biogenesis, or quality control

Exercise plays a preventive role against Alzheimer's disease

Alzheimer's disease (AD) is a progressive neurodegenerative disorder affecting the elderly population. It is predicted that the incidence of AD will be increased in the future making this disease one of the greatest medical, social, and economic challenges for individuals, families, and the health care system worldwide. The etiology of AD is multifactorial. It features increased oxidative state and deposition of amyloid plaques and neurofibrillary tangles of protein tau in the central cortex and limbic system of the brain. Here we provide an overview of the positive impacts of exercise on this challenging disease. Regular physical activity increases the endurance of cells and tissues to oxidative stress, vascularization, energy metabolism, and neurotrophin synthesis, all important in neurogenesis, memory improvement, and brain plasticity. Although extensive studies are required to understand the mechanism, it is clear that physical exercise is beneficial in the prevention of AD and other age-associated neurodegenerative disorders

Carmacks Copper Cu-Au-Ag Deposit: Mineralization and Postore Migmatization of a Stikine Arc Porphyry Copper System in Yukon, Canada

Late Triassic to Early Jurassic porphyry Cu mineralization is common in British Columbia, yet there are few age-equivalent porphyry occurrences in Yukon. This study presents new data for the enigmatic Carmacks Copper Cu-Au-Ag deposit in south-central Yukon, Canada, which is hosted in amphibolite facies metamorphic inliers within the Early Jurassic Granite Mountain batholith. Sulfide mineralization occurs mainly as net-textured bornite and chalcopyrite in leucosome, and as chalcopyrite ± pyrite blebs and disseminations in amphibolite and quartz-plagioclase-biotite schist. Several studies suggest that the Carmacks Copper deposit and the nearby Minto deposit are related to porphyry belts in British Columbia, but constraining the timing of alteration, mineralization, and metamorphism has been difficult. This study establishes a geologic and high-precision geochronologic framework for sulfide mineralization and its host rocks at the Carmacks Copper deposit, using Re-Os dating of molybdenite, and chemical abrasion-thermal ionization mass spectrometry (CA-TIMS) analysis of both whole zircon grains and laser-cut fragments of complexly zoned zircon grains. Our data indicate that the igneous protolith of the metamorphic inliers formed at 217.53 ± 0.16 Ma, followed by peak metamorphism at amphibolite facies at 205.82 ± 0.23 Ma, which occurred prior to Granite Mountain batholith emplacement but subsequent to Cu-Au-Ag mineralization of the protolith. An early phase of the Granite Mountain batholith was emplaced at 199.84 ± 0.14 Ma, followed by the main phase at 195 to 194 Ma. A second generation of metamorphic zircon in migmatite at 196.01 ± 0.12 Ma represents a partial melting event associated with Granite Mountain batholith emplacement. Two petrographically distinct populations of molybdenite are present in unstrained, net-textured copper sulfides. A sample dominated by strained molybdenite yielded an 187Re/187Os age of 212.5 ± 1.0 Ma, which represents the minimum mineralization age of the protolith. A sample dominated by euhedral grains yielded an 187Re/187Os age of 198.5 ± 0.9 Ma, constraining the maximum age of sulfide remobilization. These results indicate that primary mineralization is \u3e212.5 Ma and potentially coeval with the ~217.5 Ma generation of Late Triassic magmatism. The mineralized protolith, best interpreted as the potassic alteration zone of a Late Triassic (~217–213 Ma) porphyry Cu-Au system, was metamorphosed to amphibolite facies at ~206 Ma, and subsequently migmatized during 200 to 194 Ma intrusion of the Granite Mountain batholith. The chalcopyrite-bornite-dominant assemblage in neosome precipitated from an immiscible Cu-Fe-S melt phase that partly consumed xenocrystic molybdenite and reprecipitated new molybdenite grains. The Carmacks Copper deposit and the related Minto deposit are remnants of a Late Triassic porphyry belt, where a significant fraction of the original metal endowment was likely lost through digestion of mineralized rocks by midcrustal magma in the Early Jurassic. These Yukon deposits are rare examples of metamorphosed porphyry Cu systems in the global geologic record, where rapid tectonic burial following mineralization was the principal factor in their preservation

Resveratrol enhances exercise training responses in rats selectively bred for high running performance

High Capacity Runner (HCR) rats have been developed by divergent artificial selection for treadmill endurance running capacity to explore an aerobic biology-disease connection. The beneficial effects of resveratrol supplementation have been demonstrated in endurance running and the antioxidant capacity of resveratrol is also demonstrated. In this study we examine whether 12 weeks of treadmill exercise training and/or resveratrol can enhance performance in HCR. Indeed, resveratrol increased aerobic performance and strength of upper limbs of these rats. Moreover, we have found that resveratrol activated the AMP-activated protein kinase, SIRT1, and mitochondrial transcription factor A (p < 0.05). The changes in mitochondrial fission/fusion and Lon protease/HSP78 levels suggest that exercise training does not significantly induce damage of proteins. Moreover, neither exercise training nor resveratrol supplementation altered the content of protein carbonyls. Changes in the levels of forkhead transcription factor 1 and SIRT4 could suggest increased fat utilization and improved insulin sensitivity. These data indicate, that resveratrol supplementation enhances aerobic performance due to the activation of the AMPK-SIRT1-PGC-1 alpha pathway. (C) 2013 Elsevier Ltd. All rights reserved