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Introduction: The gut microbiome is an integral partner in host health and plays a role in immune development, altered nutrition, and pathogen prevention. The mycobiome (fungal microbiome) is considered part of the rare biosphere but is still a critical component in health. Next generation sequencing has improved our understanding of fungi in the gut, but methodological challenges remain. Biases are introduced during DNA isolation, primer design and choice, polymerase selection, sequencing platform selection, and data analyses, as fungal reference databases are often incomplete or contain erroneous sequences., Methods: Here, we compared the accuracy of taxonomic identifications and abundances from mycobiome analyses which vary among three commonly selected target gene regions (18S, ITS1, or ITS2) and the reference database (UNITE - ITS1, ITS2 and SILVA - 18S). We analyze multiple communities including individual fungal isolates, a mixed mock community created from five common fungal isolates found in weanling piglet feces, a purchased commercial fungal mock community, and piglet fecal samples. In addition, we calculated gene copy numbers for the 18S, ITS1, and ITS2 regions of each of the five isolates from the piglet fecal mock community to determine whether copy number affects abundance estimates. Finally, we determined the abundance of taxa from several iterations of our in-house fecal community to assess the effects of community composition on taxon abundance., Results: Overall, no marker-database combination consistently outperformed the others. Internal transcribed space markers were slightly superior to 18S in the identification of species in tested communities, but Lichtheimia corymbifera , a common member of piglet gut communities, was not amplified by ITS1 and ITS2 primers. Thus, ITS based abundance estimates of taxa in piglet mock communities were skewed while 18S marker profiles were more accurate. Kazachstania slooffiae displayed the most stable copy numbers (83-85) while L. corymbifera displayed significant variability (90-144) across gene regions., Discussion: This study underscores the importance of preliminary studies to assess primer combinations and database choice for the mycobiome sample of interest and raises questions regarding the validity of fungal abundance estimates., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Arfken, Frey, Carrillo, Dike, Onyeachonamm, Rivera, Davies and Summers.)

Aging has been suggested to be associated with changes in oxidative capacity, autophagy, and mitophagy in the liver, but a simultaneous evaluation of these key cellular processes is lacking. Moreover, skeletal muscle transcriptional coactivator peroxisome proliferator-activated receptor gamma coactivator (PGC)-1α has been reported to mediate inter-organ signaling through myokines with regulatory effects in the liver, but the potential role of muscle PGC-1α on hepatic changes with age remains to be resolved. The aim of the present study was therefore to investigate 1) the effect of aging on mitochondrial autophagy and mitophagy capacity in mouse liver and 2) whether muscle PGC-1α is required for maintaining autophagy and mitophagy capacity in the liver during aging. The liver was obtained from young (Young) and aged (Aged) inducible muscle-specific PGC-1α knockout (iMKO) and floxed littermate control mice (Lox). Aging increased liver p62, Parkin and BCL2/adenovirus E1B 19 kDa protein-interacting protein (BNIP)3 protein with no effect of muscle specific PGC-1α knockout, while liver Microtubule-associated protein 1A/1B-light chain 3(LC3) II/I was unchanged with age, but tended to be lower in iMKO mice than in controls. Markers of liver mitochondrial oxidative capacity and oxidative stress were unchanged with age and iMKO. However, Parkin protein levels in isolated liver mitochondria were 2-fold higher in Aged iMKO mice than in Aged controls. In conclusion, aging had no effect on oxidative capacity and lipid peroxidation in the liver. However, aging was associated with increased levels of autophagy and mitophagy markers. Moreover, muscle PGC-1α appears to regulate hepatic mitochondrial translocation of Parkin in aged mice, suggesting that the metabolic capacity of skeletal muscle can modulate mitophagy regulation in the liver during aging., Competing Interests: Declaration of competing interest No conflicts of interest, financial or otherwise, are declared by the authors., (Copyright © 2022. Published by Elsevier Inc.)

The microbiome is an integral part of chicken health and can affect immunity, nutrient utilization, and performance. The role of bacterial microbiota members in host health is relatively well established, but less attention has been paid to fungal members of the gastrointestinal tract (GIT) community. However, human studies indicate that fungi play a critical role in health. Here, we described fungal communities, or mycobiomes, in both the lumen and mucosa of the chicken ileum and cecum from hatch through 14 days of age. We also assessed the effects of delayed access to feed immediately post-hatch (PH) on mycobiome composition, as PH feed delay is commonly associated with poor health performance. Chicken mycobiomes in each of the populations were distinct and changed over time. All mycobiomes were dominated by Gibberella , but Aspergillus , Cladosporium , Sarocladium , Meyerozyma , and Penicillium were also abundant. Relative abundances of some taxa differed significantly over time. In the cecal and ileal lumens, Penicillium was present in extremely low quantities or absent during days one and two and then increased over time. Meyerozyma and Wickerhamomyces also increased over time in luminal sites. In contrast, several highly abundant unclassified fungi decreased after days one and two, highlighting the need for improved understanding of fungal gut biology. Mycobiomes from chicks fed during the first 2 days PH versus those not fed during the first 2 days did not significantly differ, except during days one and two. Similarities observed among mycobiomes of fed and unfed chicks at later timepoints suggest that delays in PH feeding do not have long lasting effects on mycobiome composition. Together, these results provide a foundation for future mycobiome studies, and suggest that negative health and production impacts of delayed feeding are not likely related to the development of fungal populations in the GIT., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Davies, Summers, Arfken, Darwish, Chaudhari, Frey, Schreier and Proszkowiec-Weglarz.)

Background: Peripheral and central hemodynamic indices are modifiable by lifestyle and medical intervention. We aimed to determine the long-term effect of intensive multifactorial treatment on peripheral and central hemodynamic indices among people with screen-detected diabetes., Methods: Between 2001 and 2006, people with screen-detected type 2 diabetes were included in the Anglo-Danish-Dutch study of Intensive Treatment of Diabetes in Primary Care (ADDITION) trial (NCT00237549, ClinicalTrials.gov). In the Danish arm, participants were invited to a clinical examination in 2015-2016, 13 years after inclusion and 8 years after trial-end. Out of 586 eligible participants who attended the clinical examination, 411 had a valid examination of central and peripheral hemodynamic indices (242 received intensive treatment and 169 received routine care). Carotid-femoral pulse wave velocity (cfPWV), central blood pressure and augmentation index were assessed by applanation tonometry. We used mixed-effect models to examine the intervention effect adjusting for cluster randomization and heart rate., Results: Randomization to intensive treatment during the trial-period was associated with a 0.58 m/s lower cfPWV (95% CI - 1.09 to - 0.06) at follow-up. Adjustment for blood pressure attenuated the association. Differences between intervention groups for central augmentation index were - 1.25% (95% CI: - 3.28 to 0.78), central pulse pressure - 1.74 mmHg (95% CI - 4.79 to 1.31), central systolic blood pressure - 3.06 mmHg (- 7.08 to 0.96), and central diastolic blood pressure - 1.70 mmHg (- 3.74 to 0.34)., Conclusions: Intensive multifactorial treatment of screen-detected type 2 diabetes has a sustained positive effect on aortic stiffness measured by cfPWV. Although all estimates pointed in favor of intensive treatment, we observed no clear beneficial effect on other hemodynamic indices., (© 2022. The Author(s).)

How can patients and their relatives make their concerns heard by healthcare professionals? Many serious adverse events are preceded by patients' worry and concern. This article explores changes in the structures and processes of healthcare that might facilitate safer systems. One important tool might be the ability of patients to become equal partners in the recording of their clinical history., (© Royal College of Physicians 2021. All rights reserved.)

Selective breeding and genetic modification have been the cornerstone of animal agriculture. However, the current strategy of breeding animals over multiple generations to introgress novel alleles is not practical in addressing global challenges such as climate change, pandemics, and the predicted need to feed a population of 9 billion by 2050. Consequently, genome editing in zygotes to allow for seamless introgression of novel alleles is required, especially in cattle with long generation intervals. We report for the first time the use of CRISPR-Cas genome editors to introduce novel PRNP allelic variants that have been shown to provide resilience towards human prion pandemics. From one round of embryo injections, we have established six pregnancies and birth of seven edited offspring, with two founders showing >90% targeted homology-directed repair modifications. This study lays out the framework for in vitro optimization, unbiased deep-sequencing to identify editing outcomes, and generation of high frequency homology-directed repair-edited calves.

The majority of human energy metabolism occurs in skeletal muscle mitochondria emphasizing the importance of understanding the regulation of myocellular mitochondrial function. The transcriptional co-activator peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α) has been characterized as a major factor in the transcriptional control of several mitochondrial components. Thus, PGC-1α is often described as a master regulator of mitochondrial biogenesis as well as a central player in regulating the antioxidant defense. However, accumulating evidence suggests that PGC-1α is also involved in the complex regulation of mitochondrial quality beyond biogenesis, which includes mitochondrial network dynamics and autophagic removal of damaged mitochondria. In addition, mitochondrial reactive oxygen species production has been suggested to regulate skeletal muscle insulin sensitivity, which may also be influenced by PGC-1α. This review aims to highlight the current evidence for PGC-1α-mediated regulation of skeletal muscle mitochondrial function beyond the effects on mitochondrial biogenesis as well as the potential PGC-1α-related impact on insulin-stimulated glucose uptake in skeletal muscle. Novelty PGC-1α regulates mitochondrial biogenesis but also has effects on mitochondrial functions beyond biogenesis. Mitochondrial quality control mechanisms, including fission, fusion, and mitophagy, are regulated by PGC-1α. PGC-1α-mediated regulation of mitochondrial quality may affect age-related mitochondrial dysfunction and insulin sensitivity.

Weaning is a period of environmental changes and stress that results in significant alterations to the piglet gut microbiome and is associated with a predisposition to disease, making potential interventions of interest to the swine industry. In other animals, interactions between the bacteriome and mycobiome can result in altered nutrient absorption and susceptibility to disease, but these interactions remain poorly understood in pigs. Recently, we assessed the colonization dynamics of fungi and bacteria in the gastrointestinal tract of piglets at a single time point post-weaning (day 35) and inferred interactions were found between fungal and bacterial members of the porcine gut ecosystem. In this study, we performed a longitudinal assessment of the fecal bacteriome and mycobiome of piglets from birth through the weaning transition. Piglet feces in this study showed a dramatic shift over time in the bacterial and fungal communities, as well as an increase in network connectivity between the two kingdoms. The piglet fecal bacteriome showed a relatively stable and predictable pattern of development from Bacteroidaceae to Prevotellaceae , as seen in other studies, while the mycobiome demonstrated a loss in diversity over time with a post-weaning population dominated by Saccharomycetaceae . The mycobiome demonstrated a more transient community that is likely driven by factors such as diet or environmental exposure rather than an organized pattern of colonization and succession evidenced by fecal sample taxonomic clustering with nursey feed samples post-weaning. Due to the potential tractability of the community, the mycobiome may be a viable candidate for potential microbial interventions that will alter piglet health and growth during the weaning transition.

The aim of the study was to investigate the impact of autophagy inhibition on skeletal muscle mitochondrial function and glucose homeostasis in young and aged mice. The transcriptional co-activator PGC-1α regulates muscle oxidative phenotype which has been shown to be linked with basal autophagic capacity. Therefore, young and aged inducible muscle-specific PGC-1α knockout (iMKO) mice and littermate lox/lox controls were used in three separate experiments performed after either saline or colchicine injections on two consecutive days: (1) Euthanization in the basal state obtaining skeletal muscle for mitochondrial respirometry, (2) whole body glucose tolerance test, and (3) in vivo insulin-stimulated 2-deoxyglucose (2-DG) uptake into skeletal muscle. Muscle PGC-1α was not required for maintaining basal autophagy flux, regardless of age. Colchicine-induced inhibition of autophagy was associated with impairments of skeletal muscle mitochondrial function, including reduced ADP sensitivity and altered mitochondrial redox balance in both young and aged mice. Colchicine treatment reduced the glucose tolerance in aged, but not young mice, and similarly in iMKO and lox/lox mice. Colchicine reduced insulin-stimulated 2-DG uptake in soleus muscle in aged mice, independently of PGC-1α, and without affecting insulin-regulated phosphorylation of proximal or distal mediators of insulin signaling. In conclusion, the results indicate that autophagy regulates the mitochondrial ADP sensitivity and redox balance as well as whole body glucose tolerance and skeletal muscle insulin sensitivity in aged mice, with no additional effects of inducible PGC-1α deletion., (© 2020 Federation of American Societies for Experimental Biology.)

Interactions between the bacteria and fungi in the gut microbiome can result in altered nutrition, pathogenicity of infection, and host development, making them a crucial component in host health. Associations between the mycobiome and bacteriome in the piglet gut, in the context of weaning, remain unknown. Weaning is a time of significant stress, dietary changes, microbial alterations, and a predisposition to infection. The loss of animal health and growth makes potential microbial interventions of interest to the swine industry. Recent studies have demonstrated the diversity and development of the microbiome in the gastrointestinal (GI) tract of piglets during weaning, resulting from the dietary and physiological changes. Despite these advances, the role of the mycobiota in piglet health and its contribution to overall microbiome development remains mostly unknown. In this study we investigated the bacteriome and the mycobiome after weaning in the GI tract organs and feces from 35-day old piglets. Following weaning, the α-diversity and amplicon sequence variants (ASVs) counts of the bacteriome increased, proximally to distally, from the stomach to the feces along the GI tract, while the mycobiome α-diversity and ASV counts were highest in the porcine stomach. β-diversity analyses show distinct clusters based on organ type in the bacteriome and mycobiome, but dispersion remained relatively constant in the mycobiome between organ/fecal sites. Bacteroidetes, Firmicutes, and Epsilonbacteraeota were the most abundant bacterial phyla present in the GI tract and feces based on mean taxonomic composition with high variation of composition found in the stomach. In the mycobiome, the dominant phyla were Ascomycota and Basidiomycota, and the stomach mycobiome did not demonstrate the same high level of variation observed in the bacteriome. Potential interactions between genera were found in the lower piglet GI bacteriome and mycobiome with positive correlations found between the fungus, Kazachstania , and several bacterial species, including Lactobacillus . Aspergillus demonstrated negative correlations with the short chain fatty acid-producing bacteria Butyricoccus , Subdoligranulum , and Fusicatenibacter . This study demonstrates the distinct colonization dynamics between fungi and bacteria in the GI tract and feces of piglets directly following weaning and the potential interactions of these microbes in the porcine gut ecosystem., (Copyright © 2019 Arfken, Frey, Ramsay and Summers.)

Impaired mitochondrial function has been implicated in the pathogenesis of age-associated metabolic diseases through regulation of cellular redox balance. Exercise training is known to promote mitochondrial biogenesis in part through induction of the transcriptional coactivator peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α). Recently, mitochondrial ADP sensitivity has been linked to reactive oxygen species (ROS) emission with potential impact on age-associated physiological outcomes, but the underlying molecular mechanisms remain unclear. Therefore, the present study investigated the effects of aging and exercise training on mitochondrial properties beyond biogenesis, including respiratory capacity, ADP sensitivity, ROS emission, and mitochondrial network structure, in myofibers from inducible muscle-specific PGC-1α-knockout mice and control mice. Aged mice displayed lower running endurance and mitochondrial respiratory capacity than young mice. This was associated with intermyofibrillar mitochondrial network fragmentation, diminished submaximal ADP-stimulated respiration, increased mitochondrial ROS emission, and oxidative stress. Exercise training reversed the decline in maximal respiratory capacity independent of PGC-1α, whereas exercise training rescued the age-related mitochondrial network fragmentation and the impaired submaximal ADP-stimulated respiration in a PGC-1α-dependent manner. Furthermore, lack of PGC-1α was associated with altered phosphorylation and carbonylation of the inner mitochondrial membrane ADP/ATP exchanger adenine nucleotide translocase 1. In conclusion, the present study provides evidence that PGC-1α regulates submaximal ADP-stimulated respiration, ROS emission, and mitochondrial network structure in mouse skeletal muscle during aging and exercise training.

The importance of the microbiota in the gastrointestinal tract of animals is recognized as a critical player in host health. Recently, the significance of the mycobiome has been recognized, but culture-independent studies are limited, especially in swine. Weaning is a time of stress, dietary changes, and a predisposition to infections, making it a time point of interest to industry. In this pilot study, we sought to assess and characterize the mycobiome in the feces of swine from birth through the critical weaning transition to investigate the mycobiome population and its temporal dynamics in piglet feces. Cultured fecal samples demonstrate a significant increase in fungal burden following weaning that does not differ from adult levels, suggesting stable colonization. Culturable fungi were not found in any environmental samples tested, including water, food, sow milk or colostrum. To determine the fungal diversity present and to address the problem of unculturable fungi, we performed a pilot study utilizing ITS and 16S rRNA focused primers for high-throughput sequencing of fungal and bacterial species, respectively. Bacterial populations increase in diversity over the experimental timeline (days 1 to 35 postbirth), but the fungal populations do not demonstrate the same temporal trend. Following weaning, there is a dynamic shift in the feces to a Saccharomycetaceae-dominated population. The shift in fungal population was because of the dominance of Kazachstania slooffiae, a poorly characterized colonizer of animal gastrointestinal tracts. This study provides insights into the early colonization and subsequent establishment of fungi during the weaning transition in piglets. Future studies will investigate the effect of the mycobiome on piglet growth and health during the weaning transition., (Published by Oxford University Press on behalf of the American Society of Animal Science 2019.)

Lifelong regular physical activity is associated with reduced risk of type 2 diabetes (T2D), maintenance of muscle mass and increased metabolic capacity. However, little is known about epigenetic mechanisms that might contribute to these beneficial effects in aged individuals. We investigated the effect of lifelong physical activity on global DNA methylation patterns in skeletal muscle of healthy aged men, who had either performed regular exercise or remained sedentary their entire lives (average age 62 years). DNA methylation was significantly lower in 714 promoters of the physically active than inactive men while methylation of introns, exons and CpG islands was similar in the two groups. Promoters for genes encoding critical insulin-responsive enzymes in glycogen metabolism, glycolysis and TCA cycle were hypomethylated in active relative to inactive men. Hypomethylation was also found in promoters of myosin light chain, dystrophin, actin polymerization, PAK regulatory genes and oxidative stress response genes. A cluster of genes regulated by GSK3β-TCF7L2 also displayed promoter hypomethylation. Together, our results suggest that lifelong physical activity is associated with DNA methylation patterns that potentially allow for increased insulin sensitivity and a higher expression of genes in energy metabolism, myogenesis, contractile properties and oxidative stress resistance in skeletal muscle of aged individuals.

Exercise training has been reported to prevent the age-induced decline in muscle mass and fragmentation of mitochondria, as well as to affect autophagy and mitophagy. The interaction between these pathways during aging as well as the similarity between such changes in human and mouse skeletal muscle is however not fully understood. Therefore the aim of the present study was to test the hypothesis that cellular degradation pathways, including apoptosis, autophagy and mitophagy are coordinately regulated in mouse and human skeletal muscle during aging and lifelong exercise training through a PGC-1α-p53 axis. Muscle samples were obtained from young untrained, aged untrained and aged lifelong exercise trained men, and from whole-body PGC-1α knockout mice and their littermate controls that were either lifelong exercise trained or sedentary young and aged. Lifelong exercise training prevented the aging-induced reduction in PGC-1α, p53 and p21 mRNA as well as the increase in LC3II and BNIP3 protein in mouse skeletal muscle, while aging decreased the BAX/Bcl-2 ratio, LC3I and BAX protein in mouse skeletal muscle without effects of lifelong exercise training. In humans, aging was associated with reduced PGC-1α mRNA as well as decreased p62 and p21 protein in skeletal muscle, while lifelong exercise training increased BNIP3 protein and decreased p53 mRNA. In conclusion, there was a divergent regulation of autophagy and apoptosis in mouse muscle with aging and lifelong exercise training, whereas healthy aged human skeletal muscle seemed rather robust to changes in apoptosis, autophagy and mitophagy markers compared with mouse muscle at the investigated age., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Background: The performance of elite breath hold divers (BHD) includes static breath hold for more than 11 minutes, swimming as far as 300 m, or going below 250 m in depth, all on a single breath of air. Diving mammals are adapted to sustain oxidative metabolism in hypoxic conditions through several metabolic adaptations, including improved capacity for oxygen transport and mitochondrial oxidative phosphorylation in skeletal muscle. It was hypothesized that similar adaptations characterized human BHD. Hence, the purpose of this study was to examine the capacity for oxidative metabolism in skeletal muscle of BHD compared to matched controls., Methods: Biopsies were obtained from the lateral vastus of the femoral muscle from 8 Danish BHD and 8 non-diving controls (Judo athletes) matched for morphometry and whole body VO2max. High resolution respirometry was used to determine mitochondrial respiratory capacity and leak respiration with simultaneous measurement of mitochondrial H2O2 emission. Maximal citrate synthase (CS) and 3-hydroxyacyl CoA dehydrogenase (HAD) activity were measured in muscle tissue homogenates. Western Blotting was used to determine protein contents of respiratory complex I-V subunits and myoglobin in muscle tissue lysates., Results: Muscle biopsies of BHD revealed lower mitochondrial leak respiration and electron transfer system (ETS) capacity and higher H2O2 emission during leak respiration than controls, with no differences in enzyme activities (CS and HAD) or protein content of mitochondrial complex subunits myoglobin, myosin heavy chain isoforms, markers of glucose metabolism and antioxidant enzymes., Conclusion: We demonstrated for the first time in humans, that the skeletal muscles of BHD are characterized by lower mitochondrial oxygen consumption both during low leak and high (ETS) respiration than matched controls. This supports previous observations of diving mammals demonstrating a lower aerobic mitochondrial capacity of the skeletal muscles as an oxygen conserving adaptation during prolonged dives., Competing Interests: The authors have declared that no competing interests exist.

The human genome is generally organized into stable chromosomes, and only tumor cells are known to accumulate kilobase (kb)-sized extrachromosomal circular DNA elements (eccDNAs). However, it must be expected that kb eccDNAs exist in normal cells as a result of mutations. Here, we purify and sequence eccDNAs from muscle and blood samples from 16 healthy men, detecting ~100,000 unique eccDNA types from 16 million nuclei. Half of these structures carry genes or gene fragments and the majority are smaller than 25 kb. Transcription from eccDNAs suggests that eccDNAs reside in nuclei and recurrence of certain eccDNAs in several individuals implies DNA circularization hotspots. Gene-rich chromosomes contribute to more eccDNAs per megabase and the most transcribed protein-coding gene in muscle, TTN (titin), provides the most eccDNAs per gene. Thus, somatic genomes are rich in chromosome-derived eccDNAs that may influence phenotypes through altered gene copy numbers and transcription of full-length or truncated genes.

Aging is associated with impaired mitochondrial function, whereas exercise training enhances mitochondrial content and function in part through activation of PGC-1α. Mitochondria form dynamic networks regulated by fission and fusion with profound effects on mitochondrial functions, yet the effects of aging and exercise training on mitochondrial network structure remain unclear. This study examined the effects of aging and exercise training on mitochondrial network structure using confocal microscopy on mitochondria-specific stains in single muscle fibers from PGC-1α KO and WT mice. Hyperfragmentation of mitochondrial networks was observed in aged relative to young animals while exercise training normalized mitochondrial network structure in WT, but not in PGC-1α KO. Mitochondrial fission protein content (FIS1 and DRP1) relative to mitochondrial content was increased with aging in both WT and PGC-1α KO mice, while exercise training lowered mitochondrial fission protein content relative to mitochondrial content only in WT. Mitochondrial fusion protein content (MFN1/2 and OPA1) was unaffected by aging and lifelong exercise training in both PGC-1α KO and WT mice. The present results provide evidence that exercise training rescues aging-induced mitochondrial fragmentation in skeletal muscle by suppressing mitochondrial fission protein expression in a PGC-1α dependent manner., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Exercise has long been recognized as a powerful physiological stimulus for a wide variety of metabolic adaptations with implications for health and performance. The metabolic effects of exercise occur during and after each exercise bout and manifest as cumulative adaptive responses to successive exercise bouts. Studies on the beneficial effects of exercise have traditionally focused on the biosynthesis of metabolic proteins and organelles. However, the recycling of cellular components by autophagy has recently emerged as an important process involved in the adaptive responses to exercise. This review covers the regulation of autophagy by exercise, with emphasis on the potential autophagy-dependent beneficial effects of exercise., (Copyright © 2017 Cold Spring Harbor Laboratory Press; all rights reserved.)

The aim of the present study was to examine the effect of lipopolysaccharide (LPS)-induced inflammation on AMP-activated protein kinase (AMPK) and pyruvate dehydrogenase (PDH) regulation in human skeletal muscle at rest and during exercise. Nine young healthy physically inactive male subjects completed two trials. In an LPS trial, the subjects received a single LPS injection (0.3 ng/kg body weight) and blood samples and vastus lateralis muscle biopsies were obtained before and 2 h after the LPS injection and immediately after a 10-min one-legged knee extensor exercise bout performed approximately 2½ h after the LPS injection. The exercise bout with muscle samples obtained before and immediately after was repeated in a control trial without LPS injection. The plasma tumor necrosis factor α concentration increased 17-fold 2 h after LPS relative to before. Muscle lactate and muscle glycogen were unchanged from before to 2 h after LPS and exercise increased muscle lactate and decreased muscle glycogen in the control (P < 0.05) and the LPS (0.05 ≤ P < 0.1) trial with no differences between the trials. AMPK, acetyl-CoA carboxylase (ACC) and PDH phosphorylation as well as PDHa activity were unaffected 2 h after LPS relative to before. Exercise decreased (P < 0.05) PDH and increased (P < 0.05) AMPK and ACC phosphorylation as well as increased (P < 0.05) PDHa activity similarly in the LPS and control trial. In conclusion, LPS-induced inflammation does not affect resting or exercise-induced AMPK and PDH regulation in human skeletal muscle. This suggests that metabolic flexibility during exercise is maintained during short-term low-grade inflammation in humans.

Background: The present study tested the hypothesis that lifelong resveratrol (RSV) supplementation counteracts an age-associated decrease in skeletal muscle oxidative capacity through peroxisome proliferator-activated receptor-γ coactivator (PGC)-1α and that RSV combined with lifelong exercise training (EX) exerts additive effects through PGC-1α in mice., Methods: 3 month old PGC-1α whole body knockout (KO) and wild type (WT) littermate mice were placed in cages with or without running wheel and fed either standard chow or standard chow with RSV supplementation (4 g/kg food) for 12 months. Young (3 months of age), sedentary mice on standard chow served as young controls. A graded running performance test and a glucose tolerance test were performed 2 and 1 week, respectively, before euthanization where quadriceps and extensor digitorum longus (EDL) muscles were removed., Results: In PGC-1α KO mice, quadriceps citrate synthase (CS) activity, mitochondrial (mt)DNA content as well as pyruvate dehydrogenase (PDH)-E1α, cytochrome (Cyt) c and vascular endothelial growth factor (VEGF) protein content were 20-75% lower and, EDL capillary-to-fiber (C:F) ratio was 15-30% lower than in WT mice. RSV and/or EX had no effect on the C:F ratio in EDL. CS activity (P=0.063) and mtDNA content (P=0.013) decreased with age in WT mice, and CS activity, mtDNA content, PDH-E1α protein and VEGF protein increased ~1.5-1.8-fold with lifelong EX in WT, but not in PGC-1α KO mice, while RSV alone had no significant effect on these proteins., Conclusion: Lifelong EX increased activity/content of oxidative proteins, mtDNA and angiogenic proteins in skeletal muscle through PGC-1α, while RSV supplementation alone had no effect. Combining lifelong EX and RSV supplementation had no additional effect on skeletal muscle oxidative and angiogenic proteins., (© 2013.)

Rationale and Objectives: The authors determine the reliability of centralized versus noncentralized (site-based) measurement of angiographic stenosis of patients enrolled into the multicenter, prospective, Asymptomatic Carotid Atherosclerosis Study by angiographic studies., Methods: Percent agreements and correlations of 244 masked and prospectively interpreted angiograms were calculated for comparison of centralized and noncentralized readers measuring the percent carotid stenosis from the same angiographic studies. Univariate summary statistics for differences in percent stenoses were calculated for these readings., Results: Agreement between readings were 88.5% and 91.8% with kappa statistics of 0.77 and 0.73 for > or = 60% and > or = 80% stenosis, respectively, for comparison of 33 centers to the designated central reader. Comparison between the designated central reader and a second central reader derived percent agreements of 85.0% and 86.5% with kappa statistics of 0.69 and 0.41 for > or = 60% and > or = 80% stenoses, respectively, for arteries selected from the original group. Hence, agreement was slightly better between the enrolling centers and the designated central reader than between the two central readers., Conclusions: Both centralized and noncentralized (site-based) methods of angiographic measurement of stenosis are equally reliable for large, prospective, masked, multicenter trials when quality control measures are instituted to ensure uniform application of eligibility criteria.