Relationship between metabolic function and skeletal muscle fatigue during a 90 s maximal isometric contraction

Sirikul, Bovorn; Hunter, Gary R.; Larson‐Meyer, D. Enette; Desmond, Renee DesmondR.; Newcomer, Bradley R.

doi:10.1139/h06-117

Cited by 17 publications

(15 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Such in vivo methods avoid the perturbations that occur when concentrations and activities of enzymes in oxidative phosphorylation and the TCA cycle are measured after removing muscle tissue from its natural state and blood supply. Both calculations of ADP TC and QMAX include the entire recovery period following exercise, which is influenced by post-exercise blood flow (Sirikul et al, 2007). The abnormal blood flow-dependent mitochondrial measures in our volunteers with diabetes suggest that altered blood flow may contribute to their mitochondrial dysfunction.…”

Section: Discussionmentioning

confidence: 99%

“…We selected a 90 s isometric exercise bout as this perturbation has been extensively modeled and utilized for assessing both aerobic and anaerobic processes (Sirikul, Hunter, Larson-Meyer, Desmond, & Newcomer, 2007). Force was monitored continuously throughout the exercise, with verbal feedback provided to the subject to help keep the force measurements within the target goal.…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Insulin resistance in type 2 diabetes youth relates to serum free fatty acids and muscle mitochondrial dysfunction

Cree-Green

Gupta

Coe

et al. 2017

Journal of Diabetes and its Complications

Self Cite

View full text Add to dashboard Cite

Aims Insulin resistance (IR) correlates with mitochondrial dysfunction, free fatty acids (FFAs), and intramyocellular lipid (IMCL) in adults with type 2 diabetes (T2D). We hypothesized that muscle IR would relate to similar factors in T2D youth. Methods Participants included 17 youth with T2D, 23 normal weight controls (LCs), and 26 obese controls (OBs) of similar pubertal stage and activity level. Results T2D and OB groups were of similar BMI. T2D youth were significantly more IR and had higher calf IMCL and serum FFA concentrations during hyperinsulinemia. ADP time constant (ADPTC), a blood-flow dependent mitochondrial function measure, was slowed and oxidative phosphorylation rates lower in T2D. In multiple linear regression of the entire cohort, lack of FFA suppression and longer ADPTC, but not IMCL or HbA1c, were independently associated with IR. Conclusion We found that elevated FFAs and mitochondrial dysfunction are early abnormalities in relatively well-controlled youth with T2D. Further, post-exercise oxidative metabolism appears affected by reduced blood flow, and is not solely an inherent mitochondrial defect. Thus, lowering FFAs and improving mitochondrial function and blood flow may be potential treatment targets in youth with T2D.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

Insulin resistance in type 2 diabetes youth relates to serum free fatty acids and muscle mitochondrial dysfunction

Cree-Green

Gupta

Coe

et al. 2017

Journal of Diabetes and its Complications

Self Cite

View full text Add to dashboard Cite

show abstract

“…In keeping with these findings, mitochondrial function has been shown to vary by sex (28). Many mitochondrial studies account for this by selecting to study one sex or balancing sex distribution within groups (10,27,53). However, in adults with vascular disease, once protein and muscle weight were corrected for, there were no differences in mitochondrial function per se (56).…”

Section: E729mentioning

confidence: 92%

“…We selected a 90-s isometric exercise bout, as this perturbation has been extensively modeled and utilized for assessing both aerobic and anaerobic processes (53). Force was monitored continuously throughout the exercise, with verbal feedback to help keep the force measurements within the target goal.…”

Section: Mri and Mrsmentioning

confidence: 99%

Peripheral insulin resistance in obese girls with hyperandrogenism is related to oxidative phosphorylation and elevated serum free fatty acids

Cree-Green

Newcomer

Coe

et al. 2015

American Journal of Physiology-Endocrinology and Metabolism

Self Cite

View full text Add to dashboard Cite

Cree-Green M, Newcomer BR, Coe G, Newnes L, Baumgartner A, Brown MS, Pyle L, Reusch JE, Nadeau KJ. Peripheral insulin resistance in obese girls with hyperandrogenism is related to oxidative phosphorylation and elevated serum free fatty acids. 31 phosphorus MR spectroscopy before, during, and after near-maximal isometric calf exercise, and peripheral IR was assessed with an 80 mU·m Ϫ2 ·min Ϫ1 hyperinsulinemic euglycemic clamp. Girls with HAS had higher androgens [free androgen index 7.9(6.6,15.5) vs. 3.5(3.0,4.0), P Ͻ 0.01] and more IR [glucose infusion rate 9.4(7.0, 12,2) vs. 14.5(13.2,15.8) mg·kg lean Ϫ1 ·min Ϫ1 , P Ͻ 0.01]. HAS girls also had increased markers of inflammation including CRP, platelets, and white blood cell count and higher serum free fatty acids during hyperinsulinemia. Mitochondrial oxidative phosphorylation was lower in HAS [0.11(0.06,0.19) vs. 0.18(0.12,0.23) mmol/s, P Ͻ 0.05], although other spectroscopy markers of mitochondrial function were similar between groups. In multivariate analysis of the entire cohort, IR related to androgens, oxidative phosphorylation, and free fatty acid concentrations during hyperinsulinemia. These relationships were present in just the HAS cohort as well. Obese girls with HAS have significant peripheral IR, which is related to elevated androgens and free fatty acids and decreased mitochondrial oxidative phosphorylation. These may provide future options as targets for therapeutic intervention.hyperandrogenism; insulin resistance; mitochondria; obesity; hyperandrogenic syndrome HYPERANDROGENIC SYNDROME (HAS), also known as polycystic ovarian syndrome (PCOS), affects at least 10 -15% of the female population in the United States, with a recent increase in prevalence associated with rising obesity rates (32). Women with HAS have a three-to fourfold increased risk of developing type 2 diabetes (T2D) compared with BMI-matched controls (37, 58). This increased risk is thought to be secondary to long-standing insulin resistance (IR) (37). There is also evidence of IR in youth with HAS (2). Similar to findings in T2D, peripheral IR as assessed with a hyperinsulinemic euglycemic clamp has been well documented in adults with HAS (7, 15), with similar but fewer data in youth (2). However, the mechanism of IR in HAS remains uncertain, and as a result the best treatments for HAS are also unclear.A leading theory explaining IR in T2D includes defects in mitochondrial function in combination with excess serum free fatty acids (FFA), which can cause alterations in intracellular insulin signaling (52). Other potential mechanisms involve altered fat metabolism and inflammation, which have been documented in T2D and HAS but have not been examined in adolescents with HAS (14,25,29,33,54). However, data examining the role of mitochondria in IR in HAS are limited and conflicting. Muscle mitochondrial oxidation gene expression for oxidative enzymes such as citrate synthase, or ␤-hydroxyacyl-CoA dehydrogenase were similar between women with and without HAS despite worse IR in the wom...

show abstract

“…However, concomitant activation of type I and type II muscle ibers in a MVIC results in a signi icant participation of oxidative phosphorylation in this exercise modality (31), and may contribute more signi icantly (Δ 16%) with the maintenance of contractile ef iciency, than the phosphocreatine (% Δ 9) and anaerobic glycolysis (Δ 10%) in the resynthesis of ATP (32). Speci ically in COPD, the reduction in the ratio of type I/type II muscle ibers (33) can signi icantly change the O 2 extraction.…”

Section: Low Muscular Capacitymentioning

confidence: 99%

Microvascular oxygen extraction during maximal isometric contraction in patients with chronic obstructive pulmonary disease

et al. 2016

View full text Add to dashboard Cite

(p=0.044) in the COPD group in MVIC-1 and 149.6% higher (p=0.006) in the MVIC-2. Microvascular extraction rate of oxygen corrected by muscle mass and total work was found to be 114.5% higher (p=0.043) in the COPD group in MVIC-1 and 210.5% higher (p=0.015) in the MVIC-2. Conclusion: COPD patients have low muscle performance and high oxygen extraction per muscle mass unit and per unit of work. The high oxygen extraction suggests that quantitative and qualitative mechanisms can be determinants of muscle performance in patients with COPD. (VEF1 = 44,5 ± 9,6 % predito; SpO2 = 94,6 ± 1,6 %). Massa magra do membro inferior foi de 8,3 ± 0,9 vs. 8,9 ± 1,0 Kg (p= ,033) Keywords

show abstract

Relationship between metabolic function and skeletal muscle fatigue during a 90 s maximal isometric contraction

Cited by 17 publications

References 32 publications

Insulin resistance in type 2 diabetes youth relates to serum free fatty acids and muscle mitochondrial dysfunction

Insulin resistance in type 2 diabetes youth relates to serum free fatty acids and muscle mitochondrial dysfunction

Peripheral insulin resistance in obese girls with hyperandrogenism is related to oxidative phosphorylation and elevated serum free fatty acids

Microvascular oxygen extraction during maximal isometric contraction in patients with chronic obstructive pulmonary disease

Contact Info

Product

Resources

About