Mechanical unloading during microgravity causes skeletal muscle atrophy and impairs mitochondrial energetics. The elevated production of reactive oxygen species (ROS) by mitochondria Nox2, coupled with impairment stress protection (e.g., SIRT1, antioxidant enzymes), contribute to atrophy. We tested the hypothesis that SIRT1 activator, SRT2104 would rescue unloading-induced dysfunction. Mitochondrial function in rat gastrocnemius soleus muscles were evaluated under three conditions (10 days):...

Coenzyme Q10 (CoQ10) is an essential component of the mitochondrial electron transfer system and a potent antioxidant. The impact CoQ10 supplementation on capacities muscle proteome largely unknown. This study determined effect concentrations, antioxidant balance, proteome, respiratory capacities. In randomized cross-over design, six Thoroughbred horses received 1600 mg/d or no supplement (control) for 30-d periods separated by 60-d washout. Muscle samples were taken at end each period....

We aimed to test the hypothesis that repeated muscle collections would not impact mitochondrial function, antioxidant status, or markers of inflammation and damage. Twenty-six mature horses (8 geldings, 18 mares; mean±SD 9.5±3.5 y) were assigned have gluteus medius samples collected at: 0 24h (n=7); 6h (n=6); 0, 6, 12h 12, (n=6). Blood was from all every for 72h, starting prior 0h collection. Data analyzed using mixed linear models. Muscle integrative (per mg tissue) electron transfer...

Abstract Various managerial, nutritional, and environmental stressors may cause excessive production of reactive oxygen species (ROS) or free radicals which can damage cells tissues, referred to as oxidative stress. Oxidative stress impair beef cattle growth performance product quality. Antioxidant enzymes are important in mitigating increased ROS prevent stress, yet little is known about skeletal muscle antioxidant status different breeds, ages temperaments. We aimed test the hypotheses...

Abstract Beef cattle breed and temperament are known to impact beef production; however, the physiological pathways linking stress growth palatability not well understood. To test hypothesis that live animal circulatory cortisol insulin-like factor 1 (IGF1) would be related temperament, production efficiency, palatability, Brahman Angus steers were classified as calm (n = 13 Angus; n 12 Brahman), intermediate 11 10 or temperamental Brahman) based on their pen score exit velocity at weaning....

We aimed to test the hypothesis that repeated muscle collections would impact mitochondrial function, antioxidant status, and markers of inflammation damage. Twenty-six horses (8 geldings, 18 mares; mean ± SD 9.5 3.5 y) had gluteus medius biopsy samples collected at: 0 24h (n=7); 6h (n = 6); 0, 6, 12h or 12, (n=6). Blood was from all every for 72h, starting prior 0h collection. Data were analyzed using mixed linear models. Muscle integrative (per mg tissue) electron transfer capacity complex...

Abstract Environmental heat stress (HS) can impair muscle mitochondrial function which may contribute to negative health outcomes, but little is known about potential treatments rescue during HS. To test the hypothesis that thyroid hormone (T3) would protect HS, samples were collected from right ventricle (RV) of 3-mo-old, crossbred gilts under 4 different environmental conditions: thermoneutral (TN; 22°C; n = 8); 1 d HS (HS1; 38°C; 7); oral supplementation 1.33 µgּ kg body weight (BW)-1ּ...

Abstract Chronic inflammation associated with aging, termed “inflamm-aging” may negatively impact overall animal health. However, the mechanisms of inflamm-aging and, therefore, effective interventions, remain unknown. Nuclear factor erythroid 2-related 2 (Nrf2; NFE2L2) is a transcription that controls antioxidant gene expression and could be target for promoting anti-inflammatory pathways. To test hypothesis supplementation nonenzymatic derived antioxidants (Protandim Nrf2 Synergizer,...

Heat stress (HS) negatively impacts animal health and impairs growth, but little is known about sex-specific responses of skeletal muscle mitochondria to HS. To test the hypothesis that HS would have more adverse effects on in females than males, samples were collected from oxidative portion semitendinosus 3-month-old female castrated male pigs under thermoneutral (TN) conditions or after 1 7 d at 39.4°C (n=8/sex/group). Mitochondrial volume density function determined via citrate synthase...

With continued trends toward more frequent and severe heat events there is a greater risk of environment-induced stress (HS). How persistently elevated core temperatures impacts body tissues remains largely unknown. Our preliminary evidence indicates HS may negatively impact cardiac tissue that biological sex play role in HS-mediated pathology. To further test the hypothesis muscle mitochondria are impacted by females than males, samples were isolated from left ventricle (LV) heart...

Abstract Prenatal transportation stress has been reported to alter behavior and adrenal glucocorticoid secretion in calves; however, the impact on mitochondrial inflammatory responses an industry-relevant stressor have not explored. Sixteen Brahman bull calves were used test hypothesis that previously stressed by utero (PNS; n = 8; mean ± SD, 654 71 kg, 11.7 0.4 months) would impaired capacity greater plasma concentrations of two pro-inflammatory cytokines [interleukin (IL)-6 tumor necrosis...

Abstract Mitochondrial abundance and efficiency correlate with meat color, but relationships between live animal mitochondria other markers of beef quality remain largely unknown. To test the hypothesis that skeletal muscle mitochondrial would be correlated post-harvest hot carcass weight, ribeye area, calculated yield grade, backfat thickness, marbling, samples were collected from longissimus thoracis Brahman Angus steers at 10 mo (25 Angus, 23 Brahman), 13 (35 33 18 Brahman) age. volume...

In cattle, prenatal transportation stress has been associated with differential methylation of genes related to metabolism, but the effects on skeletal muscle mitochondria and oxidative have not investigated. We tested hypothesis that prenatally stressed calves would exhibit increased mitochondrial function resulting in greater than from non-stressed dams. Serum longissimus thoracis samples were collected yearling Brahman whose mothers by at five time points during gestation [i.e., (PNS);...

Abstract Temperament impacts skeletal muscle mitochondria in Brahman heifers, but this relationship has not been investigated Angus steers. We hypothesized mitochondrial measures would be greater temperamental than calm steers, the trapezius (TRAP) longissimus thoracis (LT) muscle, and increase from 13 to 18 mo of age. Samples (n = 13), intermediate 12), 13) steers were evaluated for integrative (per mg tissue) oxidative phosphorylation (P) electron transfer (E) capacities by high-resolution...

Abstract Brahman cattle reportedly have decreased meat quality compared to Angus but little is known about the cellular mechanisms driving this difference. We hypothesized that live animal skeletal muscle mitochondria would be related quality. Trapezius and longissimus thoracis (LT) samples were collected from 10-mo-old steers designated as calm, intermediate, or temperamental (n=12/group/breed) based on pen score exit velocity at weaning. Samples analyzed for citrate synthase (CS)...

Abstract Mitochondrial activity correlates with meat product quality post-harvest but little is known about the relationships between live animal mitochondria and at slaughter. To test hypothesis that skeletal muscle mitochondrial markers would be correlated longissimus Warner-Bratzler shear force (WBSF) post-harvest, thoracis (LT) trapezius (TRAP) samples were collected from Brahman Angus steers (n = 36 per breed) during grazing growth phase (GP) after 120 days on feed (FP). Samples...