Mitochondrial function in sparrow pectoralis muscle

Kuzmiak, Sarah; Sweazea, Karen L.; Willis, Wayne T.

doi:10.1242/jeb.065094

Cited by 33 publications

(26 citation statements)

References 110 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Importantly, the V max values reported in Table 2, determined using Eadie-Hofstee analysis of steady state conditions established with the creatine kinase energy clamp, are in excellent agreement with state 3 rates determined conventionally with saturating addition of ADP as seen in supplementary material Fig. S1, and also as recently reported by our laboratory (Kuzmiak et al, 2012).…”

Section: Kinetic Assessment Of Respiratory Control Sensitivitysupporting

confidence: 86%

“…The state 3 (maximum) rate of mitochondrial oxygen consumption, J O , of pigeon pectoralis mitochondria oxidizing pyruvate is roughly equal to that of palmitoyl-L-carnitine (Rasmussen et al, 2004), and the pioneering work of Suarez et al showed similar trends in hummingbird pectoralis (Suarez et al, 1986). Data from pectoralis mitochondria of the house sparrow further confirm this avian pattern, as recently reported by our laboratory (Kuzmiak et al, 2012). As pyruvate (carbohydrate) and β-oxidation (fatty acid) pathways elicit equal rates of oxygen consumption, the selection of fatty acid fuel during avian flight cannot be simply explained by a higher catalytic potential for fat oxidation.…”

Section: Introductionsupporting

confidence: 86%

“…The maximal (state 3) mitochondrial oxygen consumption rate expressed per mg of mitochondrial protein is not very different between these species (Table 2; supplementary material Fig. S1) (Kuzmiak et al, 2012). As such, the energy requirements of flight can only be met because of the higher mitochondrial volume and protein density of avian myocytes.…”

Section: Control Of Respirationmentioning

confidence: 95%

“…(3) Finally, it has been shown that a reduced (high NADH/NAD + ratio) mitochondrial matrix strongly inhibits the β-oxidation of fatty acids (Lumeng et al, 1976). Our previous work has shown NADH cytochrome c reductase activity is 80% higher in sparrow versus rat skeletal muscle, indicating a greater maximal rate of electron transport chain (ETC) flux in birds than in mammals (Kuzmiak et al, 2012). Because an ETC capable of achieving a given V · O 2 at a low matrix NADH/NAD + should provide a competitive advantage for fatty acid to contribute to the oxidative fuel supply, we predicted higher conductance for electron flow down the ETC in avian than in mammalian mitochondria.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Skeletal Muscle Fuel Selection Occurs at the Mitochondrial Level

Kuzmiak-Glancy

Willis

2014

Journal of Experimental Biology

Self Cite

View full text Add to dashboard Cite

Mammals exponentially increase the rate of carbohydrate oxidation as exercise intensity rises, while birds combust lipid almost exclusively while flying at high percentages of aerobic capacity. The fuel oxidized by contracting muscle depends on many factors: whole-body fuel storage mass, mobilization, blood transport, cellular uptake, and substrate selection at the level of the mitochondrion. We examined the fuel preferences of mitochondria isolated from mammalian and avian locomotory muscles using two approaches. First, the influence of substrates on the kinetics of respiration (K m,ADP and V max ) was evaluated. For all substrates and combinations, K m,ADP was generally twofold higher in avian mitochondria. Second, fuel competition between pyruvate, glutamate and/or palmitoyl-L-carnitine at three levels of ATP free energy was determined using the principle of mass balance and the measured rates of O 2 consumption and metabolite accumulation/utilization. Avian mitochondria strongly spared pyruvate from oxidation when another substrate was available and fatty acid was the dominant substrate, regardless of energy state. Mammalian mitochondria exhibited some preference for fatty acid over pyruvate at lower flux (higher energy state), but exhibited a much greater tendency to select pyruvate and glutamate when available. Studies in sonicated mitochondria revealed twofold higher electron transport chain electron conductance in avian mitochondria. We conclude that substantial fuel selection occurs at the level of the mitochondrial matrix and that avian flight muscle mitochondria are particularly biased toward the selection of fatty acid, possibly by facilitating high β-oxidation flux by maintaining a more oxidized matrix.

show abstract

Section: Kinetic Assessment Of Respiratory Control Sensitivitysupporting

confidence: 86%

Section: Introductionsupporting

confidence: 86%

Section: Control Of Respirationmentioning

confidence: 95%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Skeletal Muscle Fuel Selection Occurs at the Mitochondrial Level

Kuzmiak-Glancy

Willis

2014

Journal of Experimental Biology

Self Cite

View full text Add to dashboard Cite

show abstract

“…In addition, the cell membranes of birds are composed of fatty acids that are more resistant to lipid peroxidation than those of mammals, and birds show lower overall lipid peroxidation rates in tissues (Hulbert and Else, 1999;Hulbert et al, 2007). Most mammals primarily use carbohydrates as fuel during exercise, whereas birds primarily burn fats to fuel flight, and this reliance on fatty acid oxidation results in relatively lower RS production in exercising birds than in mammals (Kuzmiak et al, 2012;Montgomery et al, 2012;Weber, 2009). Although burning fat may result in lower RS production in muscle mitochondria, stored fat is highly susceptible to lipid peroxidation, and, during migration, birds must build and store large amounts of fat (Costantini, 2014;Costantini et al, 2007;Pierce and McWilliams, 2014;Skrip et al, 2015).…”

Section: Among-species Differences In Bmrmentioning

confidence: 99%

The role of the antioxidant system during intense endurance exercise: lessons from migrating birds

Cooper-Mullin

McWilliams

2016

Journal of Experimental Biology

View full text Add to dashboard Cite

During migration, birds substantially increase their metabolic rate and burn fats as fuel and yet somehow avoid succumbing to overwhelming oxidative damage. The physiological means by which vertebrates such as migrating birds can counteract an increased production of reactive species (RS) are rather limited: they can upregulate their endogenous antioxidant system and/or consume dietary antioxidants ( prophylactically or therapeutically). Thus, birds can alter different components of their antioxidant system to respond to the demands of long-duration flights, but much remains to be discovered about the complexities of RS production and antioxidant protection throughout migration. Here, we use bird migration as an example to discuss how RS are produced during endurance exercise and how the complex antioxidant system can protect against cellular damage caused by RS. Understanding how a bird's antioxidant system responds during migration can lend insights into how antioxidants protect birds during other life-history stages when metabolic rate may be high, and how antioxidants protect other vertebrates from oxidative damage during endurance exercise.

show abstract

Effects of acute temperature increases on House sparrow (Passer domesticus) pectoralis muscle myonuclear domain

Jesus

Jiménez

2021

J Exp Zool Pt A

View full text Add to dashboard Cite

With rapid climate change, heat wave episodes have become more intense and more frequent. This poses a significant threat to animals, and forces them to manage these physiologically challenging conditions by adapting and/or moving. As an invasive species with a large niche breadth, House sparrows (Passer domesticus) exhibit high phenotypic flexibility that caters to seasonal changes in function and metabolism. For example, their pectoral muscle complex exhibits size and mass plasticity with winter and summer acclimation. Here, we investigated the effects of acute whole‐organism heat stress to 43°C on cellular‐level changes in House sparrow pectoralis muscle myonuclear domain (MND), the volumetric portion each nucleus is responsible for, that have gone overlooked in the current literature. House sparrows were separated into a control group, a heat‐shocked group subjected to thermal stress at 43°C for 24 h, and a recovery group that was returned to room temperature for 24 h after experiencing the same temperature treatment. Here, we found that heat‐shocked and recovery groups demonstrated a decrease in number of nuclei per millimeter of fiber and increase in MND, when compared with the control. We also found a significant positive correlation between fiber diameter and MND in the recovery group, suggesting the possibility that nuclei number constrains the extent of muscle fiber size. Together, these results show that acute heat shock alters House sparrow pectoralis muscle cellular physiology in a rigid way that could prove detrimental to long‐term muscle integrity and performance.

show abstract

Mitochondrial function in sparrow pectoralis muscle

Cited by 33 publications

References 110 publications

Skeletal Muscle Fuel Selection Occurs at the Mitochondrial Level

Skeletal Muscle Fuel Selection Occurs at the Mitochondrial Level

The role of the antioxidant system during intense endurance exercise: lessons from migrating birds

Effects of acute temperature increases on House sparrow (Passer domesticus) pectoralis muscle myonuclear domain

Contact Info

Product

Resources

About