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Wei M, Zhang N, Li XD. Characterisation of the myosin light chain kinase (MLCK) gene of Locusta migratoria and the encoded MLCK. INSECT MOLECULAR BIOLOGY 2024; 33:338-349. [PMID: 38411321 DOI: 10.1111/imb.12902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2024] [Accepted: 02/14/2024] [Indexed: 02/28/2024]
Abstract
Myosin light chain kinase (MLCK) is a dedicated kinase of myosin regulatory light chain (RLC), playing an essential role in the regulation of muscle contraction and cell motility. Much of the knowledge about MLCK comes from the study of vertebrate MLCK, and little is known about insect MLCK. Here, we identified the single MLCK gene in the locust Locusta migratoria, which spans over 1400 kb, includes 62 exons and accounts for at least five transcripts. We found that the five distinct transcripts of the locust MLCK gene are expressed in a tissue-specific manner, including three muscle-specific isoforms and two generic isoforms. To characterise the kinase activity of locust MLCK, we recombinantly expressed LmMLCK-G, the smallest locust MLCK isoform, in insect Sf9 cells. We demonstrated that LmMLCK-G is a Ca2+/calmodulin-dependent kinase that specifically phosphorylates serine 50 of locust muscle myosin RLC (LmRLC). Additionally, we found that almost all LmRLC molecules in the flight muscle and the hindleg muscles of adult locusts are phosphorylated.
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Affiliation(s)
- Miao Wei
- State Key Laboratory of Integrated Management of Insect Pests and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Ning Zhang
- State Key Laboratory of Integrated Management of Insect Pests and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Xiang-Dong Li
- State Key Laboratory of Integrated Management of Insect Pests and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- University of Chinese Academy of Sciences, Beijing, China
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2
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Protzen G, Matoso B, Doma K, de Oliveira S, Boullosa D. Does the Repeated-Bout Effect Influence Post-Activation Performance Enhancement in Recreational Runners? RESEARCH QUARTERLY FOR EXERCISE AND SPORT 2024:1-8. [PMID: 38959957 DOI: 10.1080/02701367.2024.2353719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Accepted: 04/23/2024] [Indexed: 07/05/2024]
Abstract
Purpose: This study examined how a low dose of an eccentric-oriented lunge exercise could induce the repeated-bout effect (RBE) and affect the subsequent post-activation performance enhancement (PAPE) in recreational runners. Methods: Twenty male recreational runners (32.1 ± 2.8 years; 173.4 ± 6.1 cm; 73.3 ± 11.5 kg; 57.8 ± 7.2 mL·kg-1·min-1) were divided into control (N = 10) and experimental (N = 10) groups. In the first and fourth weeks, the groups were assessed for jump capacity, dynamic balance, and submaximal running kinematics before and after an incremental shuttle-run test until exhaustion. The experimental group was also submitted to two sessions of the eccentric-oriented lunge exercise (3 sets of 10 repetitions with 2 min of passive recovery) in the second and third weeks. Results: We observed that the first session promoted muscle damage, which was significantly (p < .05) reduced after the second training session, thus indicating an RBE. Meanwhile, there was no effect of the RBE on dynamic balance and submaximal running kinematics in the post-intervention. However, there was a significant increase in countermovement jump height (p = .008) for the experimental group when compared to the control group, although no PAPE was observed. Conclusions: The current results demonstrate that a simple, low-dose eccentric-oriented exercise may induce an RBE, leading to reduced muscle damage and a possibly improved lower limbs' muscle power in recreational runners. However, the absence of PAPE effects suggests that the RBE may not directly influence the potentiation/fatigue balance after fatiguing running exercises.
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Affiliation(s)
| | | | | | | | - Daniel Boullosa
- University of León
- Federal University of Mato Grosso do Sul
- James Cook University
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3
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Lee E, May H, Kazmierczak K, Liang J, Nguyen N, Hill JA, Gillette TG, Szczesna-Cordary D, Chang AN. The MYPT2-regulated striated muscle-specific myosin light chain phosphatase limits cardiac myosin phosphorylation in vivo. J Biol Chem 2024; 300:105652. [PMID: 38224947 PMCID: PMC10851227 DOI: 10.1016/j.jbc.2024.105652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2023] [Revised: 01/02/2024] [Accepted: 01/04/2024] [Indexed: 01/17/2024] Open
Abstract
The physiological importance of cardiac myosin regulatory light chain (RLC) phosphorylation by its dedicated cardiac myosin light chain kinase has been established in both humans and mice. Constitutive RLC-phosphorylation, regulated by the balanced activities of cardiac myosin light chain kinase and myosin light chain phosphatase (MLCP), is fundamental to the biochemical and physiological properties of myofilaments. However, limited information is available on cardiac MLCP. In this study, we hypothesized that the striated muscle-specific MLCP regulatory subunit, MYPT2, targets the phosphatase catalytic subunit to cardiac myosin, contributing to the maintenance of cardiac function in vivo through the regulation of RLC-phosphorylation. To test this hypothesis, we generated a floxed-PPP1R12B mouse model crossed with a cardiac-specific Mer-Cre-Mer to conditionally ablate MYPT2 in adult cardiomyocytes. Immunofluorescence microscopy using the gene-ablated tissue as a control confirmed the localization of MYPT2 to regions where it overlaps with a subset of RLC. Biochemical analysis revealed an increase in RLC-phosphorylation in vivo. The loss of MYPT2 demonstrated significant protection against pressure overload-induced hypertrophy, as evidenced by heart weight, qPCR of hypertrophy-associated genes, measurements of myocyte diameters, and expression of β-MHC protein. Furthermore, mantATP chase assays revealed an increased ratio of myosin heads distributed to the interfilament space in MYPT2-ablated heart muscle fibers, confirming that RLC-phosphorylation regulated by MLCP, enhances cardiac performance in vivo. Our findings establish MYPT2 as the regulatory subunit of cardiac MLCP, distinct from the ubiquitously expressed canonical smooth muscle MLCP. Targeting MYPT2 to increase cardiac RLC-phosphorylation in vivo may improve baseline cardiac performance, thereby attenuating pathological hypertrophy.
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Affiliation(s)
- Eunyoung Lee
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Herman May
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Katarzyna Kazmierczak
- Department of Molecular and Cellular Pharmacology, University of Miami Miller School of Medicine, Miami, Florida, USA
| | - Jingsheng Liang
- Department of Molecular and Cellular Pharmacology, University of Miami Miller School of Medicine, Miami, Florida, USA
| | - Nhu Nguyen
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Joseph A Hill
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Thomas G Gillette
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Danuta Szczesna-Cordary
- Department of Molecular and Cellular Pharmacology, University of Miami Miller School of Medicine, Miami, Florida, USA
| | - Audrey N Chang
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, Texas, USA; Pak Center for Mineral Metabolism and Clinical Research, UTSW Medical Center, Dallas, Texas, USA.
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4
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Angelidis A, Overgaard K, Vandenboom R. Potentiation of force by extracellular potassium is not dependent on muscle length in mouse EDL muscle. Am J Physiol Cell Physiol 2024; 326:C529-C539. [PMID: 38145294 DOI: 10.1152/ajpcell.00456.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Revised: 12/11/2023] [Accepted: 12/11/2023] [Indexed: 12/26/2023]
Abstract
Increases in myofiber extracellular potassium with prolonged contractile activity can potentiate twitch force. Activity-dependent potentiation, another mechanism of force increase in skeletal muscle, has a strong dependence on muscle or sarcomere length. Thus, potassium-mediated twitch potentiation could also be length-dependent. However, this has not been previously investigated. To this end, we used isolated C57BL/6 mouse extensor digitorum longus (EDL) muscles and elicited twitches at 0.9 Lo, Lo, and 1.1 Lo (Lo refers to optimal length) in normal (5 mM) and high (10 mM) potassium solutions. Potentiation magnitude was similar to previous observations and was not significantly different between lengths (0.9 Lo: 12.3 ± 4.4%, Lo: 12.2 ± 3.6%, 1.1 Lo: 11.8 ± 4.8%, values are means ± SD). Exposure to dantrolene sodium, a compound that attenuates calcium release, reduced twitch force across lengths by ∼70%. When dantrolene-affected muscles were subsequently exposed to high potassium, potentiation was similar to that observed in the absence of the former. In total, these findings provide novel information on potassium-mediated twitch potentiation.NEW & NOTEWORTHY Here, we investigated the length-dependence of twitch force potentiation by extracellular potassium in mouse extensor digitorum longus (EDL) in vitro, at 25°C. Potentiation magnitude did not display a statistically significant difference between the examined muscle lengths. These results describe, for the first time, the relationship of this form of potentiation with muscle length, thus furthering the understanding of how it is integrated in in vivo muscle function.
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Affiliation(s)
- Angelos Angelidis
- Department of Kinesiology, Centre for Bone and Muscle Health, Brock University, St. Catharines, Ontario, Canada
| | - Kristian Overgaard
- Exercise Biology, Department of Public Health, Aarhus University, Aarhus, Denmark
| | - Rene Vandenboom
- Department of Kinesiology, Centre for Bone and Muscle Health, Brock University, St. Catharines, Ontario, Canada
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Urbański R, Biel P, Kot S, Perenc D, Aschenbrenner P, Stastny P, Krzysztofik M. Impact of active intra-complex rest intervals on post-back squat versus hip thrust jumping potentiation. Sci Rep 2023; 13:19593. [PMID: 37950054 PMCID: PMC10638422 DOI: 10.1038/s41598-023-47042-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Accepted: 11/08/2023] [Indexed: 11/12/2023] Open
Abstract
This study investigated the impact of active rest intervals within a lower body complex training session on post-activation performance enhancement (PAPE) response in amateur soccer players. Twelve soccer players took part in four different experimental conditions. These sessions included 2 sets of lower body complex-paired exercises, each involving 3 repetitions of either back squats or hip thrusts at 90% one-repetition maximum (1RM) as a conditioning activity paired with a broad jump and countermovement jump. Between those exercises in active intra-complex rest interval conditions, participants were performing 8 repetitions of bench press at 75%1RM or, in passive intra-complex rest interval conditions, rested while seated. A significant main effect of a set to increase broad jump length (p = 0.002), countermovement jump height (p = 0.002), and modified reactive strength index (p = 0.005) was revealed, without any significant differences between conditions. Post-hoc comparisons showed a significant increase in broad jump length from baseline to Set-2 (231 ± 13 vs. 234 ± 13 cm; p = 0.003; ES = 0.22). On the other hand, countermovement jump height and modified reactive strength index significantly increased from baseline to Set-1 (34.4 ± 3.6 vs. 35.6 ± 3.9 cm; p = 0.027; ES = 0.31 and 0.4 ± 0.05 vs. 0.45 ± 0.09; p = 0.005; ES = 0.66). Results of this study showed that to sustain a high training density, sports practitioners may incorporate upper body exercises within the intra-complex rest interval during lower limb complex training sessions and still elicit a significant PAPE effect.
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Affiliation(s)
- Robert Urbański
- Department of Biomechanics and Sports Engineering, Gdansk University of Physical Education and Sport, Gdańsk, Poland
| | - Piotr Biel
- Department of Sport and Physical Education, AGH University of Science and Technology, Krakow, Poland
| | - Sebastian Kot
- Nutrition and Sports Performance Research Group, The Jerzy Kukuczka Academy of Physical Education in Katowice, 40-065, Katowice, Poland
| | - Dawid Perenc
- Nutrition and Sports Performance Research Group, The Jerzy Kukuczka Academy of Physical Education in Katowice, 40-065, Katowice, Poland
| | - Piotr Aschenbrenner
- Department of Biomechanics and Sports Engineering, Gdansk University of Physical Education and Sport, Gdańsk, Poland
| | - Petr Stastny
- Department of Sport Games, Faculty of Physical Education and Sport, Charles University in Prague, Prague, Czech Republic
| | - Michał Krzysztofik
- Nutrition and Sports Performance Research Group, The Jerzy Kukuczka Academy of Physical Education in Katowice, 40-065, Katowice, Poland.
- Department of Sport Games, Faculty of Physical Education and Sport, Charles University in Prague, Prague, Czech Republic.
- Institute of Sport Sciences, The Jerzy Kukuczka Academy of Physical Education in Katowice, Poland, Mikołowska 72A str., 40-065, Katowice, Poland.
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Peyton MP, Yang TY, Higgins L, Markowski TW, Murray K, Vue C, Parker LL, Lowe DA. Natural aging and ovariectomy induces parallel phosphoproteomic alterations in skeletal muscle of female mice. Aging (Albany NY) 2023; 15:7362-7380. [PMID: 37580837 PMCID: PMC10457050 DOI: 10.18632/aging.204959] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Accepted: 07/24/2023] [Indexed: 08/16/2023]
Abstract
The loss of skeletal muscle strength mid-life in females is associated with the decline of estrogen. Here, we questioned how estrogen deficiency might impact the overall skeletal muscle phosphoproteome after contraction, as force production induces phosphorylation of several muscle proteins. Phosphoproteomic analyses of the tibialis anterior muscle after contraction in two mouse models of estrogen deficiency, ovariectomy (Ovariectomized (Ovx) vs. Sham) and natural aging-induced ovarian senescence (Older Adult (OA) vs. Young Adult (YA)), identified a total of 2,593 and 3,507 phosphopeptides in Ovx/Sham and OA/YA datasets, respectively. Further analysis of estrogen deficiency-associated proteins and phosphosites identified 66 proteins and 21 phosphosites from both datasets. Of these, 4 estrogen deficiency-associated proteins and 4 estrogen deficiency-associated phosphosites were significant and differentially phosphorylated or regulated, respectively. Comparative analyses between Ovx/Sham and OA/YA using Ingenuity Pathway Analysis (IPA) found parallel patterns of inhibition and activation across IPA-defined canonical signaling pathways and physiological functional analysis, which were similarly observed in downstream GO, KEGG, and Reactome pathway overrepresentation analysis pertaining to muscle structural integrity and contraction, including AMPK and calcium signaling. IPA Upstream regulator analysis identified MAPK1 and PRKACA as candidate kinases and calcineurin as a candidate phosphatase sensitive to estrogen. Our findings highlight key molecular signatures and pathways in contracted muscle suggesting that the similarities identified across both datasets could elucidate molecular mechanisms that may contribute to skeletal muscle strength loss due to estrogen deficiency.
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Affiliation(s)
- Mina P. Peyton
- Department of Rehabilitation Medicine, Division of Rehabilitation Science, University of Minnesota – Twin Cities, Minneapolis, MN 55455, USA
- Department of Computer Science, Bioinformatics and Computational Biology Program, University of Minnesota, Minneapolis, MN 55455, USA
| | - Tzu-Yi Yang
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota – Twin Cities, Minneapolis, MN 55455, USA
| | - LeeAnn Higgins
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota – Twin Cities, Minneapolis, MN 55455, USA
| | - Todd W. Markowski
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota – Twin Cities, Minneapolis, MN 55455, USA
| | - Kevin Murray
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota – Twin Cities, Minneapolis, MN 55455, USA
| | - Cha Vue
- Department of Rehabilitation Medicine, Division of Rehabilitation Science, University of Minnesota – Twin Cities, Minneapolis, MN 55455, USA
| | - Laurie L. Parker
- Department of Computer Science, Bioinformatics and Computational Biology Program, University of Minnesota, Minneapolis, MN 55455, USA
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota – Twin Cities, Minneapolis, MN 55455, USA
| | - Dawn A. Lowe
- Department of Rehabilitation Medicine, Division of Rehabilitation Science, University of Minnesota – Twin Cities, Minneapolis, MN 55455, USA
- Department of Rehabilitation Medicine, Division of Physical Therapy, University of Minnesota – Twin Cities, Minneapolis, MN 55455, USA
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So BR, Kim S, Jang SH, Kim MJ, Lee JJ, Kim SR, Jung SK. Dietary protocatechuic acid redistributes tight junction proteins by targeting Rho-associated protein kinase to improve intestinal barrier function. Food Funct 2023; 14:4777-4791. [PMID: 37128780 DOI: 10.1039/d3fo00605k] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Inflammatory bowel disease (IBD) is continuously increasing globally and caused by intestinal barrier dysfunction. Although protocatechuic acid (PCA) has a protective effect on colitis, the molecular mechanisms underlying its contribution to intestinal barrier function remain unknown. Transepithelial electrical resistance (TEER) and FITC-dextran permeability measurements reveled that PCA suppresses lipopolysaccharide (LPS) and tumor necrosis factor (TNF)-α-induced increase in intestinal permeability; zonula occludens (ZO)-1 and claudin-2 redistribution was also suppressed in the epithelial cell membranes of differentiated Caco-2 cells. PCA was found to directly bind Rho-associated coiled-coil containing protein kinase (ROCK), subsequently suppressing myosin light chain (MLC) phosphorylation. Notably, PCA binds ROCK to a similar degree as Y27632, a selective ROCK inhibitor. Orally administering PCA (5 or 25 mg per kg per day) to C57BL/6 mice alleviated the 3% dextran sulfate sodium (DSS)-induced colitis symptoms including reduced colon length, disrupted intestinal barrier structure, and increased proinflammatory cytokines expressions, such as interleukin (IL)-1β, TNF-α, and IL-6. Furthermore, orally administering PCA suppressed DSS-induced ZO-1 and claudin-2/4 redistribution in mice colon membrane fractions. Therefore, PCA may serve as a promising nutraceutical to improve gut health and alleviate IBD by maintaining intestinal barrier function in vitro and in vivo.
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Affiliation(s)
- Bo Ram So
- School of Food Science and Biotechnology, Kyungpook National University, Daegu 41566, Republic of Korea.
| | - San Kim
- School of Food Science and Biotechnology, Kyungpook National University, Daegu 41566, Republic of Korea.
| | - Se Hyeon Jang
- School of Food Science and Biotechnology, Kyungpook National University, Daegu 41566, Republic of Korea.
| | - Min Jeong Kim
- School of Food Science and Biotechnology, Kyungpook National University, Daegu 41566, Republic of Korea.
| | - Jeong Jae Lee
- School of Food Science and Biotechnology, Kyungpook National University, Daegu 41566, Republic of Korea.
| | - Soo Rin Kim
- School of Food Science and Biotechnology, Kyungpook National University, Daegu 41566, Republic of Korea.
- Research Institute of Tailored Food Technology, Kyungpook National University, Daegu, 41566, Republic of Korea
| | - Sung Keun Jung
- School of Food Science and Biotechnology, Kyungpook National University, Daegu 41566, Republic of Korea.
- Research Institute of Tailored Food Technology, Kyungpook National University, Daegu, 41566, Republic of Korea
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Post-contraction potentiation can react inversely to post-activation potentiation depending on the test contraction force. Neurosci Lett 2023; 801:137132. [PMID: 36801240 DOI: 10.1016/j.neulet.2023.137132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 01/24/2023] [Accepted: 02/13/2023] [Indexed: 02/17/2023]
Abstract
The surface electromyographic (EMG) activity of the biceps brachii during weak elbow flexion reportedly increases immediately after strong elbow flexion, even during the exertion of a given force. This phenomenon is called post-contraction potentiation (EMG-PCP). However, the effects of test contraction intensity (TCI) on EMG-PCP remain unclear. This study evaluated PCP levels at various TCI values. Sixteen healthy participants were asked to perform a force matching task (2%, 10%, or 20% of the maximum voluntary contraction [MVC]) before (Test 1) and after (Test 2) a conditioning contraction (50% of MVC). With a 2% TCI, the EMG amplitude was higher in Test 2 than in Test 1. With a 20% TCI, the EMG amplitude was lower in Test 2 than in Test 1. Furthermore, EMG spectral analyses showed that the α- and β-band power ratios in Test 2 were enhanced by 2% TCI compared with Test 1. These findings suggest that TCI is crucial in determining the EMG-force relationship immediately after a brief intensive contraction.
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Grosicki GJ, Zepeda CS, Sundberg CW. Single muscle fibre contractile function with ageing. J Physiol 2022; 600:5005-5026. [PMID: 36268622 PMCID: PMC9722590 DOI: 10.1113/jp282298] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 10/07/2022] [Indexed: 01/05/2023] Open
Abstract
Ageing is accompanied by decrements in the size and function of skeletal muscle that compromise independence and quality of life in older adults. Developing therapeutic strategies to ameliorate these changes is critical but requires an in-depth mechanistic understanding of the underlying physiology. Over the past 25 years, studies on the contractile mechanics of isolated human muscle fibres have been instrumental in facilitating our understanding of the cellular mechanisms contributing to age-related skeletal muscle dysfunction. The purpose of this review is to characterize the changes that occur in single muscle fibre size and contractile function with ageing and identify key areas for future research. Surprisingly, most studies observe that the size and contractile function of fibres expressing slow myosin heavy chain (MHC) I are well-preserved with ageing. In contrast, there are profound age-related decrements in the size and contractile function of the fibres expressing the MHC II isoforms. Notably, lifelong aerobic exercise training is unable to prevent most of the decrements in fast fibre contractile function, which have been implicated as a primary mechanism for the age-related loss in whole-muscle power output. These findings reveal a critical need to investigate the effectiveness of other nutritional, pharmaceutical or exercise strategies, such as lifelong resistance training, to preserve fast fibre size and function with ageing. Moreover, integrating single fibre contractile mechanics with the molecular profile and other parameters important to contractile function (e.g. phosphorylation of regulatory proteins, innervation status, mitochondrial function, fibre economy) is necessary to comprehensively understand the ageing skeletal muscle phenotype.
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Affiliation(s)
- Gregory J. Grosicki
- Biodynamics and Human Performance Center, Georgia Southern University (Armstrong Campus), Savannah, Georgia, USA
| | - Carlos S. Zepeda
- Exercise and Rehabilitation Sciences Graduate Program, Department of Physical Therapy, Marquette University, Milwaukee, Wisconsin, USA
| | - Christopher W. Sundberg
- Exercise and Rehabilitation Sciences Graduate Program, Department of Physical Therapy, Marquette University, Milwaukee, Wisconsin, USA
- Athletic and Human Performance Research Center, Marquette University, Milwaukee, Wisconsin, USA
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Flywheel eccentric overload exercises versus barbell half squats for basketball players: Which is better for induction of post-activation performance enhancement? PLoS One 2022; 17:e0277432. [PMID: 36409686 PMCID: PMC9678314 DOI: 10.1371/journal.pone.0277432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 10/27/2022] [Indexed: 11/22/2022] Open
Abstract
OBJECTIVE This study compared the post-activation performance enhancement (PAPE) effects of a flywheel eccentric overload (FEOL) exercise and barbell half squats (BHS) on countermovement jump (CMJ) and 30 m sprint performance. METHODS Twelve male collegiate competitive basketball players were enrolled in this study and they implemented two training protocols: barbell half squat (BHS) and flywheel eccentric overload (FEOL) training. The BHS protocol included three intensities of load: low (40% 1RM), medium (60% 1RM), and high (80% 1RM), with each intensity consisting of 5 sets of 3 repetitions. The FEOL protocol included three inertia intensities: low (0. 015 kg∙m2), medium (0.035 kg∙m2), and high (0.075 kg∙m2), with each intensity consisting of 3 sets of 6 repetitions. The measurement time points were before training (baseline) and at 3, 6, 9, and 12 minutes after training. A two-stage (stage-I and stage-II) randomized crossover design was used to determine the acute effects of both protocols on CMJ and sprint performance. RESULTS At each training intensity, the jump height, jump peak power output (PPO), jump impulse and 30m sprint speed at 3, 6, 9, and 12 minutes after BHS and FEOL training did not change significantly compared to the baseline. A 2-way ANOVA analysis indicated significant main effects of rest intervals on jump height, jump PPO, and jump impulse, as well as 30m sprint speed. The interaction of the Time × protocol showed a significant effect on jump height between BHS and FEOL groups at high intensity in stage-I (F = 3.809, p = 0.016, df = 4) and stage-II (F = 3.044, p = 0.037, df = 4). And in high training intensity, the jump height at 3 (7.78 ± 9.90% increase, ES = 0.561), 6 (8.96 ± 12.15% increase, ES = 0.579), and 9 min (8.78 ± 11.23% increase, ES = 0.608) were enhanced in I-FEOL group compared with I-BHS group (F = 3.044, p = 0.037, df = 4). In stage-II, the impulse and sprint speed of the FEOL group were significantly higher than those of the BHS group at 6, 9, and 12 min under low (FEOL = 0.015kg∙m2, BHS = 40%1RM), medium(FEOL = 0.035kg∙m2, BHS = 60%1RM), and high (FEOL = 0.075kg∙m2, BHS = 80%1RM) intensities. Furthermore, the sprint speed of the two training protocols did not change at different time points. The interaction of Time × training intensity showed lower sprint speeds in the II-BHS group at a high intensity (BHS = 80%1RM) compared to low (BHS = 40%1RM) and medium (BHS = 60%1RM) training intensities, especially at 9 min and 12 min rest intervals. CONCLUSION Although barbell half squat training and flywheel eccentric overload training did not provide a significant PAPE effect on explosive power (CMJ and sprint) in male basketball players, FEOL training showed a better potential effect on enhanced CMJ jump performance at the high training intensity.
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11
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Peyton MP, Yang TY, Higgins L, Markowski TW, Vue C, Parker LL, Lowe DA. Global phosphoproteomic profiling of skeletal muscle in ovarian hormone-deficient mice. Physiol Genomics 2022; 54:417-432. [PMID: 36062884 PMCID: PMC9639773 DOI: 10.1152/physiolgenomics.00104.2022] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 08/05/2022] [Accepted: 08/30/2022] [Indexed: 11/22/2022] Open
Abstract
Protein phosphorylation is important in skeletal muscle development, growth, regeneration, and contractile function. Alterations in the skeletal muscle phosphoproteome due to aging have been reported in males; however, studies in females are lacking. We have demonstrated that estrogen deficiency decreases muscle force, which correlates with decreased myosin regulatory light chain phosphorylation. Thus, we questioned whether the decline of estrogen in females that occurs with aging might alter the skeletal muscle phosphoproteome. C57BL/6J female mice (6 mo) were randomly assigned to a sham-operated (Sham) or ovariectomy (Ovx) group to investigate the effects of estrogen deficiency on skeletal muscle protein phosphorylation in a resting, noncontracting condition. After 16 wk of estrogen deficiency, the tibialis anterior muscle was dissected and prepped for label-free nano-liquid chromatography-tandem mass spectrometry phosphoproteomic analysis. We identified 4,780 phosphopeptides in tibialis anterior muscles of ovariectomized (Ovx) and Sham-operated (Sham) control mice. Further analysis revealed 647 differentially regulated phosphopeptides (Benjamini-Hochberg adjusted P value < 0.05 and 1.5-fold change ratio) that corresponded to 130 proteins with 22 proteins differentially phosphorylated (3 unique to Ovx, 2 unique to Sham, 6 upregulated, and 11 downregulated). Differentially phosphorylated proteins associated with the sarcomere, cytoplasm, and metabolic and calcium signaling pathways were identified. Our work provides the first global phosphoproteomic analysis in females and how estrogen deficiency impacts the skeletal muscle phosphoproteome.
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Affiliation(s)
- Mina P Peyton
- Division of Rehabilitation Science, Department of Rehabilitation Medicine, University of Minnesota, Twin Cities, Minneapolis, Minnesota
- Department of Computer Science, Bioinformatics and Computational Biology Program, University of Minnesota, Minneapolis, Minnesota
| | - Tzu-Yi Yang
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Twin Cities, Minneapolis, Minnesota
| | - LeeAnn Higgins
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Twin Cities, Minneapolis, Minnesota
| | - Todd W Markowski
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Twin Cities, Minneapolis, Minnesota
| | - Cha Vue
- Division of Rehabilitation Science, Department of Rehabilitation Medicine, University of Minnesota, Twin Cities, Minneapolis, Minnesota
| | - Laurie L Parker
- Department of Computer Science, Bioinformatics and Computational Biology Program, University of Minnesota, Minneapolis, Minnesota
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Twin Cities, Minneapolis, Minnesota
| | - Dawn A Lowe
- Division of Rehabilitation Science, Department of Rehabilitation Medicine, University of Minnesota, Twin Cities, Minneapolis, Minnesota
- Division of Physical Therapy, Department of Rehabilitation Medicine, University of Minnesota, Twin Cities, Minneapolis, Minnesota
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12
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Mechanisms of Estrogen Influence on Skeletal Muscle: Mass, Regeneration, and Mitochondrial Function. Sports Med 2022; 52:2853-2869. [PMID: 35907119 DOI: 10.1007/s40279-022-01733-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/24/2022] [Indexed: 10/16/2022]
Abstract
Human menopause is widely associated with impaired skeletal muscle quality and significant metabolic dysfunction. These observations pose significant challenges to the quality of life and mobility of the aging population, and are of relevance when considering the significantly greater losses in muscle mass and force-generating capacity of muscle from post-menopausal females relative to age-matched males. In this regard, the influence of estrogen on skeletal muscle has become evident across human, animal, and cell-based studies. Beneficial effects of estrogen have become apparent in mitigation of muscle injury and enhanced post-damage repair via various mechanisms, including prophylactic effects on muscle satellite cell number and function, as well as membrane stability and potential antioxidant influences following injury, exercise, and/or mitochondrial stress. In addition to estrogen replacement in otherwise deficient states, exercise has been found to serve as a means of augmenting and/or mimicking the effects of estrogen on skeletal muscle function in recent literature. Detailed mechanisms behind the estrogenic effect on muscle mass, strength, as well as the injury response are beginning to be elucidated and point to estrogen-mediated molecular cross talk amongst signalling pathways, such as apoptotic signaling, contractile protein modifications, including myosin regulatory light chain phosphorylation, and the maintenance of muscle satellite cells. This review discusses current understandings and highlights new insights regarding the role of estrogen in skeletal muscle, with particular regard to muscle mass, mitochondrial function, the response to muscle damage, and the potential implications for human physiology and mobility.
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13
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Trybulski R, Makar P, Alexe DI, Stanciu S, Piwowar R, Wilk M, Krzysztofik M. Post-Activation Performance Enhancement: Save Time With Active Intra-Complex Recovery Intervals. Front Physiol 2022; 13:840722. [PMID: 35874519 PMCID: PMC9298750 DOI: 10.3389/fphys.2022.840722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Accepted: 05/23/2022] [Indexed: 11/13/2022] Open
Abstract
This study aimed to determine whether the intra-complex active recovery within the strength-power potentiating complex will impact the upper-body post-activation performance enhancement effect and how the magnitude of this effect will change across the upper-body complex training session. Thirteen resistance-trained males [the age, body mass, height, experience in resistance training, and one-repetition maximum (1RM) in bench press were 27 ± 4 years; 92.3 ± 15.4 kg; 182 ± 6 cm; 6.4 ± 2.4 years, and 118 ± 29 kg, respectively) participated in this study. Each participant completed a baseline bench press throw performance assessment at 30% 1RM. Next, five strength-power potentiating complexes consisting of a bench press at 80% 1RM were tested until the average barbell velocity decreased by 10% as a conditioning activity, and 6 min later, a re-test of bench press throw was carried out. During one experimental session during the rest interval inside the complex, they performed swiss ball leg curls, while between the complexes, a plank exercise (PAP-A) was performed. During the second experimental session, participants performed no exercises within the strength-power potentiating complexes and between them (PAP). Under control conditions, participants ran the same protocol (as the PAP condition) without the conditioning activity (CTRL). Friedman's test showed significant differences in peak (test = 90.634; p < 0.0001; Kendall's W = 0.410) and average (test = 74.172; p < 0.0001; Kendall's W = 0.336) barbell velocities during bench press throw. Pairwise comparisons indicated that the peak and average barbell velocities significantly increased in the fourth set [p = 0.022, effect size (ES) = 0.76 and p = 0.013, ES = 0.69, respectively], and the average barbell velocity was also increased in the second set (p = 0.018, ES = 0.77) in comparison to the baseline value during the PAP-A condition. Moreover, the peak barbell velocity was increased in the second (p = 0.008, ES = 0.72) and third (p = 0.019, ES = 0.76) sets compared to the baseline value during the PAP condition. This study showed that body-weight lower-body exercise as an intra-complex active recovery did not impair the upper-body post-activation performance enhancement effect across the complex training session.
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Affiliation(s)
- Robert Trybulski
- Provita Zory Medical Center, Zory, Poland.,Department of Medical Sciences, The Wojciech Korfanty School of Economics, Katowice, Poland
| | - Piotr Makar
- Faculty of Physical Education, Gdańsk University of Physical Education and Sport, Gdańsk, Poland
| | - Dan Iulian Alexe
- Faculty of Movement, Sports and Health Sciences, Vasile Alecsandri University of Bacău, Bacău, Romania
| | - Silvius Stanciu
- Faculty of Food Science and Engineering, Dunarea de Jos University of Galati, Galati, Romania
| | - Rafał Piwowar
- Department of Sports Training, The Jerzy Kukuczka Academy of Physical Education in Katowice, Katowice, Poland
| | - Michal Wilk
- Institute of Sport Sciences, The Jerzy Kukuczka Academy of Physical Education in Katowice, Katowice, Poland
| | - Michal Krzysztofik
- Institute of Sport Sciences, The Jerzy Kukuczka Academy of Physical Education in Katowice, Katowice, Poland
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14
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Cormier P, Freitas TT, Loturco I, Turner A, Virgile A, Haff GG, Blazevich AJ, Agar-Newman D, Henneberry M, Baker DG, McGuigan M, Alcaraz PE, Bishop C. Within Session Exercise Sequencing During Programming for Complex Training: Historical Perspectives, Terminology, and Training Considerations. Sports Med 2022; 52:2371-2389. [PMID: 35816233 DOI: 10.1007/s40279-022-01715-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/30/2022] [Indexed: 10/17/2022]
Abstract
The primary aim of this narrative review was to outline the historical genesis of resistance training strategies that incorporate high-load, low-velocity exercises and low-load, high-velocity exercises in the same training session allowing for different "exercise sequences" to be simultaneously implemented. Discrepancies between scientific works and the terminology used within contemporary sport science publications are identified. Upon review of the literature, we propose "complex training" to be considered an umbrella term with 4 different implementations, generally used to indicate a method in which movement velocity or load is altered between sets and/or exercises within the same session with the aim of improving slow and fast force expression. We propose the following terminology for said implementations: contrast training-exercise sequence with alternating high-load and low-load (higher-velocity) exercises in a set-by-set fashion within the same session (corresponding with 'contrast pairs' and 'intra-contrast rest'); descending training-several sets of high-load (e.g., back squat) exercises completed before the execution of several sets of low-load, higher-velocity (e.g., vertical jump) exercises within the same session; ascending training-several sets of low-load, higher-velocity exercises completed before several sets of high-load exercises within the same session; and French contrast training-subset of contrast training in which a series of exercises are performed in sequence within a single session: heavy compound exercise, plyometric exercise, light-to-moderate load compound exercise that maximises movement speed (i.e., external power), and a plyometric exercise (often assisted). Finally, practical applications and training considerations are presented.
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Affiliation(s)
- Patrick Cormier
- Canadian Sport Institute Pacific, Victoria, BC, Canada.,Exercise Science, Physical and Health Education, University of Victoria, Victoria, BC, Canada
| | - Tomás T Freitas
- UCAM Research Center for High Performance Sport, Catholic University of Murcia, UCAM, Murcia, Spain. .,NAR, Nucleus of High Performance in Sport, São Paulo, Brazil. .,SCS, Strength & Conditioning Society, Rome, Italy. .,Faculty of Sport, Catholic University of Murcia, Murcia, Spain.
| | - Irineu Loturco
- NAR, Nucleus of High Performance in Sport, São Paulo, Brazil
| | - Anthony Turner
- Faculty of Science and Technology, London Sport Institute, Middlesex University, London, UK
| | - Adam Virgile
- College of Nursing and Health Sciences, University of Vermont, Vermont, USA
| | - G Gregory Haff
- School of Medical and Health Sciences, Edith Cowan University, Joondalup, Australia.,School of Health and Society, University of Salford, Manchester, UK
| | - Anthony J Blazevich
- SCS, Strength & Conditioning Society, Rome, Italy.,School of Medical and Health Sciences, Edith Cowan University, Joondalup, Australia
| | - Dana Agar-Newman
- Canadian Sport Institute Pacific, Victoria, BC, Canada.,Exercise Science, Physical and Health Education, University of Victoria, Victoria, BC, Canada
| | - Molly Henneberry
- Canadian Sport Institute Pacific, Victoria, BC, Canada.,Exercise Science, Physical and Health Education, University of Victoria, Victoria, BC, Canada
| | - Daniel G Baker
- School of Medical and Health Sciences, Edith Cowan University, Joondalup, Australia
| | - Michael McGuigan
- School of Medical and Health Sciences, Edith Cowan University, Joondalup, Australia.,Department of Sport and Exercise Science, Auckland University of Technology, Auckland, New Zealand
| | - Pedro E Alcaraz
- UCAM Research Center for High Performance Sport, Catholic University of Murcia, UCAM, Murcia, Spain.,SCS, Strength & Conditioning Society, Rome, Italy
| | - Chris Bishop
- Faculty of Science and Technology, London Sport Institute, Middlesex University, London, UK
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15
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Zero AM, Paris MT, Rice CL. Frequency dependent coexistence of muscle fatigue and potentiation assessed by concentric isotonic contractions in human plantar flexors. J Appl Physiol (1985) 2022; 133:490-505. [PMID: 35796610 DOI: 10.1152/japplphysiol.00214.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The purpose was to investigate whether post-activation potentiation (PAP) mitigates power (i.e., torque x angular velocity) loss during dynamic fatiguing contractions and subsequent recovery by enhancing either muscle torque or angular velocity in human plantar flexors. In 12 participants, electrically stimulated (1, 10 and 50 Hz) dynamic contractions were done during a voluntary isotonic fatiguing protocol (20 and 50% voluntary decreases) until a 75% loss in voluntary peak power, and throughout 30 minutes of recovery. At the initial portion of fatigue (20% decrease), power responses of evoked low frequencies (1 and 10 Hz) were enhanced due to PAP (156 and 137%, respectively, P<0.001), while voluntary maximal efforts were depressed due to fatiguing mechanisms. Following the fatiguing task, prolonged low-frequency force depression (PLFFD) was evident by reduced 10:50 Hz peak power ratios (21 - 24%) from 3-min onwards during the 30-min recovery (P<0.005). Inducing PAP with maximal voluntary contractions during PLFFD enhanced the peak power responses of low frequencies (1 and 10 Hz) by 128 - 160 %, P<0.01. This PAP response mitigated the effects of PLFFD as the 1:50 (P<0.05) and 10:50 (P>0.4) Hz peak power ratios were greater or not different from the pre-fatigue values. Additionally, PAP enhanced peak torque more than peak angular velocity during both baseline and fatigue measurements (P<0.03). These results indicate that PAP can ameliorate PLFFD acutely when evaluated during concentric isotonic contractions and that peak torque is enhanced to a greater degree compared to peak angular velocity at baseline and in a fatigued state.
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Affiliation(s)
- Alexander M Zero
- School of Kinesiology, Faculty of Health Sciences, grid.39381.30Western University, London, ON, Canada
| | - Michael T Paris
- School of Kinesiology, Faculty of Health Sciences, grid.39381.30Western University, London, ON, Canada
| | - Charles L Rice
- Department of Anatomy and Cell Biology, grid.443228.bWestern University, London, Ontario, Canada
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16
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Angelidis A, Vandenboom R. The effect of muscle length on post-tetanic potentiation of C57BL/6 and skMLCK -/- mouse EDL muscles. J Muscle Res Cell Motil 2022; 43:99-111. [PMID: 35771335 DOI: 10.1007/s10974-022-09620-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Accepted: 05/12/2022] [Indexed: 11/25/2022]
Abstract
Post-tetanic potentiation of fast-twitch skeletal muscle is dependent on muscle length, with greater potentiation observed at shorter compared to longer lengths. The structural effects of the primary potentiation mechanism, phosphorylation of the regulatory light chain (RLC) of myosin, are thought to explain this relationship. The purpose of these experiments was to determine whether the length-dependence of potentiation would be attenuated in the absence of RLC phosphorylation. To this end, we compared isometric twitch potentiation of mouse extensor digitorum longus (EDL) muscles with (wildtype, WT) and without (skeletal myosin light chain kinase knockout, skMLCK-/-) phosphorylation. Force was measured at five muscle lengths (0.90 Lo, 0.95 Lo, Lo, 1.05 Lo, 1.10 Lo, where Lo refers to optimal length) prior to and following a tetanic train. In accordance with prior findings, potentiation was dependent on muscle length, with greater values observed at short (e.g., 44.3 ± 4.6% for WT, 33.5 ± 6.2% for skMLCK-/-, at 0.90 Lo) compared to long lengths (e.g., 16.9 ± 1.3% for WT, 9.1 ± 1.8% for skMLCK-/-, at 1.10 Lo) in both genotypes. WT muscles displayed greater potentiation compared to their skMLCK-/- counterparts across lengths (e.g., 16.9 ± 1.6% vs 7.3 ± 1.5% at Lo). However, the relationship between potentiation and muscle length was not different between genotypes. Thus, the alternative mechanisms of potentiation, present in the skMLCK-/- EDL, display a length-dependence of post-tetanic potentiation similar to RLC phosphorylation-dominant potentiation. Additional mechanisms may be required to explain the length-dependence of potentiation.
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Affiliation(s)
- Angelos Angelidis
- Department of Kinesiology, Centre for Bone and Muscle Health, Brock University, 1812 Sir Isaac Brock Way, St. Catharines, ON, L2S 3A1, Canada.
| | - Rene Vandenboom
- Department of Kinesiology, Centre for Bone and Muscle Health, Brock University, 1812 Sir Isaac Brock Way, St. Catharines, ON, L2S 3A1, Canada
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17
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Nitric oxide and skeletal muscle contractile function. Nitric Oxide 2022; 122-123:54-61. [PMID: 35405336 PMCID: PMC10167965 DOI: 10.1016/j.niox.2022.04.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 03/23/2022] [Accepted: 04/05/2022] [Indexed: 11/21/2022]
Abstract
Nitric oxide (NO) is complex modulator of skeletal muscle contractile function, capable of increasing or decreasing force and power output depending on multiple factors. This review explores the effects and potential mechanisms for modulation of skeletal muscle contractile function by NO, from pharmacological agents in isolated muscle preparations to dietary nitrate supplementation in humans and animals. Pharmacological manipulation in vitro suggests that NO signaling diminishes submaximal isometric force, whereas dietary manipulation in vivo suggest that NO enhances submaximal force. The bases for these different responses are unknown but could reflect dose-dependent effects. Maximal isometric force is unaffected by physiologically relevant levels of NO, which do not induce overt protein oxidation. Pharmacological and dietary manipulation of NO signaling enhances the maximal rate of isometric force development, unloaded shortening velocity, and peak power. We hypothesize that these effects are mediated by post-translational modifications of myofibrillar proteins that modulate thick filament regulation of contraction (e.g., mechanosensing and strain-dependence of cross-bridge kinetics). NO effects on contractile function appear to have some level of fiber type and sex-specificity. The mechanisms behind NO-mediated changes in skeletal muscle function need to be explored through proteomics analysis and advanced biophysical assays to advance the development of small molecules and open intriguing therapeutic and ergogenic possibilities for aging, disease, and athletic performance.
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18
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Nowak SJ, Dobi KC. Taking flight: an educational primer for use with "A novel mechanism for activation of myosin regulatory light chain by protein kinase C-delta in Drosophila". Genetics 2022; 220:iyab187. [PMID: 35239966 PMCID: PMC8893254 DOI: 10.1093/genetics/iyab187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 10/11/2021] [Indexed: 12/02/2022] Open
Abstract
Muscles are required for animal movement, feeding, heartbeat, and reproduction. Disruption of muscle function can lead to mobility impairments and diseases like muscular dystrophy and cardiac myopathy; therefore, research in this area has significant implications for public health. Recent work by Vaziri and colleagues has taken genetic, cell biological, and biochemical approaches to identify Protein kinase C-d (Pkcδ) as a novel regulator of the essential myosin light chain 2 (MLC2) by phosphorylation. The authors determine which residues of MLC2 are modified by Pkcδ and show that phosphorylation by Pkcδ is required for proper sarcomere assembly and function. This study underscores the importance of Drosophila melanogaster as a model system for muscle function and highlights how protein phosphorylation is a vital part of post-translational gene regulation.
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Affiliation(s)
- Scott J Nowak
- Department of Molecular and Cellular Biology, Kennesaw State University, Kennesaw, GA 30144, USA
- Master of Science in Integrative Biology Program, Kennesaw State University, Kennesaw, GA 30144, USA
| | - Krista C Dobi
- Department of Natural Sciences, Bernard M. Baruch College, City University of New York, New York, NY 10010, USA
- The Graduate Center, PhD Program in Biology, City University of New York, New York, NY 10016, USA
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19
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Villalon-Gasch L, Penichet-Tomas A, Sebastia-Amat S, Pueo B, Jimenez-Olmedo JM. Postactivation Performance Enhancement (PAPE) Increases Vertical Jump in Elite Female Volleyball Players. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19010462. [PMID: 35010722 PMCID: PMC8744649 DOI: 10.3390/ijerph19010462] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 12/26/2021] [Accepted: 12/29/2021] [Indexed: 12/24/2022]
Abstract
The purpose of this study was to verify if a conditioning activity was effective to elicit postactivation performance enhancement (PAPE) and to increase the performance in vertical jump (VJ) in elite female volleyball players. Eleven national Superliga-2 volleyball players (22.6 ± 3.5 years) were randomly assigned to an experimental and control group. Countermovement jumps (CMJ) were performed on eight occasions: before (Pre-PAPE) and after activation (Post-PAPE), after the match (Pre-Match), and after each of the five-match sets (Set 1 to 5). ANOVA showed significantly increased jump performance for the experiment between baseline (Pre-PAPE) and all the following tests: +1.3 cm (Post-PAPE), +3.0 cm (Pre-Match), +4.8 cm (Set 1), +7.3 cm (Set 2), +5.1 cm (Set 3), +3.6 cm (Set 4), and +4.0 cm (Set 5), all showing medium to large effect size (0.7 < ES < 2.4). The performance of the control group did not show significant increases until Set 3 (+3.2 cm) and Set 5 (+2.9 cm), although jump heights were always lower for the control group than the experimental. The use of conditioning activity generates increased VJ performance in Post-PAPE tests and elicited larger PAPE effects that remain until the second set of a volleyball match.
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20
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Zero AM, Kirk EA, Rice CL. Firing rate trajectories of human motor units during activity-dependent muscle potentiation. J Appl Physiol (1985) 2021; 132:402-412. [PMID: 34913736 DOI: 10.1152/japplphysiol.00672.2021] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
During activity-dependent potentiation (ADP) motor unit firing rates (MUFRs) are lower, however, the mechanism for this response is not known. During increasing torque isometric contractions at low contraction intensities, MUFR trajectories initially accelerate and saturate demonstrating a non-linear response due to the activation of persistent inward currents (PICs) at the motoneuron. The purpose was to assess whether PICs are a factor in the reduction of MUFRs during ADP. To assess this, MUFR trajectories were fit with competing functions of linear regression and a rising exponential (i.e., acceleration and saturation). Using fine-wire electrodes, discrete MU potential trains were recorded in the tibialis anterior during slowly increasing dorsiflexion contractions to 10% of maximal voluntary contraction following both voluntary (post-activation potentiation; PAP) and evoked (post-tetanic potentiation; PTP) contractions. In 8 participants, 25 MUs were recorded across both ADP conditions and compared to the control with no ADP effect. During PAP and PTP, the average MUFRs were 16.4% and 9.2% lower (both P≤ 0.001), respectively. More MUFR trajectories were better fit to the rising exponential during control (16/25) compared to PAP (4/25, P<0.001) and PTP (8/25, P=0.03). The MU samples that had a rising exponential MUFR trajectory during PAP and PTP displayed an ~11% lower initial acceleration compared to control (P<0.05). Thus, synaptic amplification and MUFR saturation due to PIC properties are attenuated during ADP regardless of the type of conditioning contraction. This response may contribute to lower MUFRs and likely occurred because synaptic input is reduced when contractile function is enhanced.
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Affiliation(s)
- Alexander M Zero
- School of Kinesiology, Faculty of Health Sciences, The University of Western Ontario, London, ON, Canada
| | - Eric A Kirk
- School of Kinesiology, Faculty of Health Sciences, The University of Western Ontario, London, ON, Canada
| | - Charles L Rice
- School of Kinesiology, Faculty of Health Sciences, The University of Western Ontario, London, ON, Canada.,Department of Anatomy and Cell Biology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Ontario, Canada
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21
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Brink NJ, Constantinou D, Torres G. Postactivation performance enhancement (PAPE) of sprint acceleration performance. Eur J Sport Sci 2021; 22:1411-1417. [PMID: 34252001 DOI: 10.1080/17461391.2021.1955012] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Postactivation performance enhancement (PAPE) is a principle that an acute bout of high-intensity voluntary exercise is followed by an enhancement in strength, speed or power production. This study intended to show a direct correlation between intensity, specificity and the outcome of a maximal task of sprint accelerations compared to a previously defined weighted plyometric intervention. In a randomised controlled, double-blind trial, professional footballers undertook 20 m maximal sprint accelerations at a baseline and at 2 and 6 min post-intervention after 1 of 3 interventions; 2 repetitions of 20 m sprint accelerations (S), 3 × 10 alternative leg weighted bounding (P) and control (C). Relative to the baseline there was a significant improvement for S over 10 and 20 m at 2 min of 0.12m.s-1 and 0.11m.s-1 and 6 min of 0.11m.s-1 and 0.12m.s-1. Relative to the baseline P also had a significant improvement over 10 and 20 m at 2 min 0.09m.s-1 and 0.09m.s-1 and 6 min of 0.11m.s-1 and 0.09m.s-1. There was a significant improvement in C between 2 and 6 min post-intervention at 10 and 20 m of 0.06m.s-1 and 0.08m.s-1. This finding suggests a maximal sprint acceleration may enhance the outcome of a subsequent maximal sprint acceleration at 2 min, but the latter results could not be directly attributed to the interventions as previous testing is likely to have influenced these outcomes.
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Affiliation(s)
- Nicholas J Brink
- Faculty of Health Sciences, Centre for Exercise Science and Sports Medicine, University of the Witwatersrand, Johannesburg, South Africa.,FIMS Collaborating Centre of Sports Medicine, Johannesburg, South Africa
| | - Demitri Constantinou
- Faculty of Health Sciences, Centre for Exercise Science and Sports Medicine, University of the Witwatersrand, Johannesburg, South Africa.,FIMS Collaborating Centre of Sports Medicine, Johannesburg, South Africa
| | - Georgia Torres
- Faculty of Health Sciences, Centre for Exercise Science and Sports Medicine, University of the Witwatersrand, Johannesburg, South Africa.,FIMS Collaborating Centre of Sports Medicine, Johannesburg, South Africa
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22
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Crespo E, Ruiz-Navarro JJ, Cuenca-Fernández F, Arellano R. Post-Eccentric Flywheel Underwater Undulatory Swimming Potentiation in Competitive Swimmers. J Hum Kinet 2021; 79:145-154. [PMID: 34400994 PMCID: PMC8336562 DOI: 10.2478/hukin-2021-0068] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Underwater undulatory swimming (UUS) influences overall swimming performance, therefore swimmers should try to maximize it. This research aimed to: 1) assess the effects of an activation protocol based on post-activation performance enhancements upon UUS; and 2) evaluate the differences between males and females. Seventeen competitive swimmers (male = 10; female = 7) participated in a cross-sectional study designed to test performance in UUS at 10 m after a traditional swimming warm-up (TRA) and after adding to the TRA 4 maximal half-squat repetitions on an inertial flywheel device (PAPE). A speedometer and an electronic timing system were used to obtain kinematic variables such as time, frequency and velocity at 10-m, which were processed with MATLAB®. A paired sample t test was applied to determine the differences of the kinematic variables between the TRA and PAPE. An independent sample t test was used to determine the effects of the PAPE in males and females. Participants reduced the time to cover 10 m after PAPE compared to the TRA (males: 5.77 ± 0.44 to 5.64 ± 0.46; females 6.34 ± 0.80 to 6.09 ± 0.66; p < 0.05). In addition, trends towards improvements in UUS velocity were obtained for males and females. However, push-off velocity and frequency showed a different tendency between genders (p < 0.05). In conclusion, the warm-up including repetitions on the flywheel device improved UUS performance. Some differences were obtained between genders after PAPE. Further research should confirm if the benefits obtained after the eccentric overload would depend either on gender or on other components such as fiber type composition.
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Affiliation(s)
- Esteban Crespo
- Aquatics Lab. Department of Physical Education and Sports. Faculty of Sport Sciences. Carretera de Alfacar, sn, 18011 – Granada. University of Granada. Spain
| | - Jesús Juan Ruiz-Navarro
- Aquatics Lab. Department of Physical Education and Sports. Faculty of Sport Sciences. Carretera de Alfacar, sn, 18011 – Granada. University of Granada. Spain
| | - Francisco Cuenca-Fernández
- Aquatics Lab. Department of Physical Education and Sports. Faculty of Sport Sciences. Carretera de Alfacar, sn, 18011 – Granada. University of Granada. Spain
| | - Raúl Arellano
- Aquatics Lab. Department of Physical Education and Sports. Faculty of Sport Sciences. Carretera de Alfacar, sn, 18011 – Granada. University of Granada. Spain
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23
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Zimmermann HB, Costa FE, Sakugawa R, MacIntosh B, Diefenthaeler F, Dal Pupo J. Plyometric exercise enhances twitch contractile properties but fails to improve voluntary rate of torque development in highly trained sprint athletes. Eur J Sport Sci 2021; 22:857-866. [PMID: 33840359 DOI: 10.1080/17461391.2021.1916083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Purpose: The objective of this study was to evaluate a plyometric conditioning activity (3 sets of 5 countermovement jumps, [CA]) for twitch properties and voluntary knee extension. Methods: After a familiarization session, fourteen highly trained sprint athletes, 12 men (23.25 ± 7.17 years) and 2 women (23.0 ± 2.8 years) performed 2 experiments, each in a randomized order (crossover design). In one experiment, the time-course of twitch contractile properties was evaluated with and without the previous CA at 2, min intervals to 10 min of recovery. In the second session, maximal voluntary knee extension was evaluated at the same recovery intervals, for control and experimental condition in random order. Results: Mixed-model ANOVA with Bonferroni post-hoc revealed significant differences between pre-test and 2 min (p < 0.01, ES = 0.42) and 4 min (p < 0.01, ES = 0.20) for peak twitch torque of quadriceps femoris muscles confirming postactivation potentiation [PAP] at these times. Twitch rate of torque development (RTD) was significantly greater than pre-test value only at 2 min (p < 0.01, ES = 0.58) after the CA. Twitch contraction time and ½ relaxation time were not significantly difference from pre-test values after the CA (p > 0.05). No significant difference was observed for voluntary RTD following CA. Conclusion: The plyometric CA increased twitch peak torque and RTD consistent with PAP; however, there was no effect of CA on voluntary RTD of knee extension at any time after the plyometric CA. Even with PAP confirmed, we observed that the CA fails to improve isometric RTD of quadriceps femoris muscles. HighlightsA plyometric CA significantly increased twitch peak torque (at 2 and 4 min) and twitch rate of torque development (at 2 min) of quadriceps femoris muscles, indicating postactivation potentiation (PAP).No effect was observed for twitch contraction time and ½ relaxation time after the CA.No improvement was observed on voluntary rate of torque development evaluated at the same time intervals.
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Affiliation(s)
- Haiko Bruno Zimmermann
- Biomechanics Laboratory, Center of Sports, Federal University of Santa Catarina, Florianopolis, Brazil
| | - Filipe Estácio Costa
- Biomechanics Laboratory, Center of Sports, Federal University of Santa Catarina, Florianopolis, Brazil
| | - Raphael Sakugawa
- Biomechanics Laboratory, Center of Sports, Federal University of Santa Catarina, Florianopolis, Brazil
| | - Brian MacIntosh
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Canada
| | - Fernando Diefenthaeler
- Biomechanics Laboratory, Center of Sports, Federal University of Santa Catarina, Florianopolis, Brazil
| | - Juliano Dal Pupo
- Biomechanics Laboratory, Center of Sports, Federal University of Santa Catarina, Florianopolis, Brazil
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Krčmár M, Krčmárová B, Bakaľár I, Šimonek J. Acute Performance Enhancement Following Squats Combined With Elastic Bands on Short Sprint and Vertical Jump Height in Female Athletes. J Strength Cond Res 2021; 35:318-324. [PMID: 33337702 DOI: 10.1519/jsc.0000000000003881] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
ABSTRACT Krčmár, M, Krčmárová, B, Bakaľár, I, and Šimonek, J. Acute performance enhancement after squats combined with elastic bands on short sprint and vertical jump height in female athletes. J Strength Cond Res 35(2): 318-324, 2021-The main purpose of this study was to compare back squats with and without elastic bands on sprint and vertical jump height. Fourteen female athletes (21.9 ± 2.3 years; 177.5 ± 6.36 cm; 66.2 ± 6.2 kg; 1 repetition maximum [1RM]/ body mass: 1.96 ± 0.14) agreed to participate. On 4 separate days, athletes walked freely for 5 minutes (CON), performed 3 sets of 4 repetitions at 85% of their 1RM with 20% or 30% (BAND20 or BAND30) of the total resistance originated from elastic bands, or performed 3 sets and 4 repetitions at 85% of their 1RM with an isoinertial load (ISO) before performance tests. Posttesting began 5 and 10 minutes after the last set of squats and included sprints over 3, 5, and 10-m, squat jump (SJ), and countermovement (CMJ) vertical jump height. The results of this study show that all postactivation performance enhancement (PAPE) protocols significantly improved 10-m sprint time (p < 0.05 to p < 0.01). Only BAND30 significantly improved 3-m and 5-m sprint times at both times of posttesting (p < 0.01). Comparison of PAPE protocols showed a significant difference when comparing BAND30 vs. ISO in SJ height in favor of BAND30 only when the best SJ height results from both posttesting times were selected (p < 0.01, g = 1.08). The results of this study suggest that all PAPE protocols were able to enhance short sprints and vertical jump height, but it seems that there is a greater trend to achieve better performance after performing the BAND30 protocol that can be seen by higher effect sizes achieved almost in all tests compared with the other PAPE protocols.
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Affiliation(s)
- Matúš Krčmár
- Department of Physical Education and Sports, Faculty of Education, Constantine the Philosopher University, Nitra, Slovakia
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Kumar RA, Kelley RC, Hahn D, Ferreira LF. Dietary nitrate supplementation increases diaphragm peak power in old mice. J Physiol 2021; 598:4357-4369. [PMID: 33460123 DOI: 10.1113/jp280027] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Accepted: 07/14/2020] [Indexed: 02/01/2023] Open
Abstract
KEY POINTS Respiratory muscle function declines with ageing, contributing to breathing complications in the elderly. Here we report greater in vitro respiratory muscle contractile function in old mice receiving supplemental NaNO3 for 14 days compared with age-matched controls. Myofibrillar protein phosphorylation, which enhances contractile function, did not change in our study - a finding inconsistent with the hypothesis that this post-translational modification is a mechanism for dietary nitrate to improve muscle contractile function. Nitrate supplementation did not change the abundance of calcium-handling proteins in the diaphragm of old mice, in contrast with findings from the limb muscles of young mice in previous studies. Our findings suggest that nitrate supplementation enhances myofibrillar protein function without affecting the phosphorylation status of key myofibrillar proteins. ABSTRACT Inspiratory muscle (diaphragm) function declines with age, contributing to ventilatory dysfunction, impaired airway clearance, and overall decreased quality of life. Diaphragm isotonic and isometric contractile properties are reduced with ageing, including maximal specific force, shortening velocity and peak power. Contractile properties of limb muscle in both humans and rodents can be improved by dietary nitrate supplementation, but effects on the diaphragm and mechanisms behind these improvements remain poorly understood. One potential explanation underlying the nitrate effects on contractile properties is increased phosphorylation of myofibrillar proteins, a downstream outcome of nitrate reduction to nitrite and nitric oxide. We hypothesized that dietary nitrate supplementation would improve diaphragm contractile properties in aged mice. To test our hypothesis, we measured the diaphragm function of old (24 months) mice allocated to 1 mm NaNO3 in drinking water for 14 days (n = 8) or untreated water (n = 6). The maximal rate of isometric force development (∼30%) and peak power (40%) increased with nitrate supplementation (P < 0.05). There were no differences in the phosphorylation status of key myofibrillar proteins and abundance of Ca2+-release proteins in nitrate vs. control animals. In general, our study demonstrates improved diaphragm contractile function with dietary nitrate supplementation and supports the use of this strategy to improve inspiratory function in ageing populations. Additionally, our findings suggest that dietary nitrate improves diaphragm contractile properties independent of changes in abundance of Ca2+-release proteins or phosphorylation of myofibrillar proteins.
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Affiliation(s)
- Ravi A Kumar
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL
| | - Rachel C Kelley
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL
| | - Dongwoo Hahn
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL
| | - Leonardo F Ferreira
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL
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Wilson C, Naber N, Cooke R. The role of the super-relaxed state of myosin in human metabolism. Metabol Open 2020; 9:100068. [PMID: 33364594 PMCID: PMC7753139 DOI: 10.1016/j.metop.2020.100068] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 11/15/2020] [Accepted: 11/19/2020] [Indexed: 12/16/2022] Open
Abstract
Background The super-relaxed state of myosin (SRX) plays a fundamental role in maintaining the low resting metabolic rate of skeletal muscle. Our previous work on this state has been in animal models. Piperine is a small molecule that has been shown to destabilize the SRX in rabbit fast twitch fibers. Methods Here we extend this work to human muscle obtained from biopsies of the vastus lateralis of both lean and obese subjects. The slow release of nucleotides by myosin in the SRX was measured by incubating permeable fibers in a fluorescent analog of ATP and chasing with ATP. Results The fraction of myosin heads in the SRX was 0.48 ± 0.04 with a lifetime of 148 ± 5 s in lean subjects and a fraction of 0.41 ± 0.05 and a lifetime of 176 ± 7 s in obese subjects. Addition of 100 μM piperine decreased the SRX population by 43 ± 7% in lean subjects and 36 ± 7% in obese subjects, with little change in lifetimes. Addition of piperine to human cardiac cells had no effect on the SRX, a requirement for a drug to treat metabolic diseases. Conclusions In human muscle the SRX and its responses to piperine are similar to those seen previously, with no significant differences between muscles from lean and obese subjects. Thus analogs of piperine that have greater specificity could provide effective treatment for metabolic diseases. The SRX provides a potential mechanism contributing to the large dynamic range of metabolic rate.
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Affiliation(s)
- Clyde Wilson
- Department of Biochemistry and Biophysics, University of California, San Francisco, CA, 94143, USA
| | - Nariman Naber
- Department of Biochemistry and Biophysics, University of California, San Francisco, CA, 94143, USA
| | - Roger Cooke
- Department of Biochemistry and Biophysics, University of California, San Francisco, CA, 94143, USA
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Effect of New Zealand Blackcurrant Extract on Isometric Contraction-Induced Fatigue and Recovery: Potential Muscle-Fiber Specific Effects. Sports (Basel) 2020; 8:sports8100135. [PMID: 33076273 PMCID: PMC7602451 DOI: 10.3390/sports8100135] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 09/24/2020] [Accepted: 10/14/2020] [Indexed: 11/26/2022] Open
Abstract
New Zealand blackcurrant (NZBC) extract has shown performance-enhancing effects during cycling, running and sport climbing. We examined effects of NZBC extract on (1) voluntary and twitch force of the quadriceps femoris muscles during repeated isometric contraction-induced fatigue, (2) twitch force during recovery and (3) muscle fiber-specific effects. Familiarized recreationally active males (n = 12, age: 24 ± 5 yrs; height: 180 ± 5 cm; body mass: 89 ± 11 kg) performed sixteen, 5-s voluntary maximal isometric contractions (iMVC) separated by 3-s rest. Twitch force was recorded before, during the 3-s rests and 5-min recovery. Supplementation consisted of 7-days intake of NZBC extract (600 mg∙day−1 containing 210 mg anthocyanin) in a double-blind, randomized, placebo-controlled crossover design with a 14-days washout. NZBC extract allowed for greater force in the first quartile of the iMVCs. Twitch force at baseline was 12% higher with NZBC extract (p = 0.05). However, there was no effect of NZBC for twitch force during the 16-iMVCs and recovery. Based on the maximum post-activation potentiation during the placebo 16-iMVCs, four subjects were classified of having a predominant type I or II muscle fiber typology. In type II, NZBC extract provided a trend for increased MVC force (~14%) in the first quartile and for type I in the fourth quartile (~10%). In type I, NZBC extract seemed to have higher twitch forces during the fatiguing exercise protocol and recovery, indicating increased fatigue resistance. New Zealand blackcurrant extract affects force during repeated maximal isometric contractions. Future work on mechanisms by NZBC extract for muscle fiber-specific fatigue-induced force responses is warranted.
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Cuenca-Fernández F, Batalha NM, Ruiz-Navarro JJ, Morales-Ortiz E, López-Contreras G, Arellano R. Post high intensity pull-over semi-tethered swimming potentiation in national competitive swimmers. J Sports Med Phys Fitness 2020; 60:1526-1535. [PMID: 32608939 DOI: 10.23736/s0022-4707.20.11136-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND The swimming community has shown considerable interest in using dry-land warm-ups as a method of impacting performance. This study compared the effects of high-resistance pull-over and swimming warm-up in semi-tethered resisted swimming. METHODS An incremental-load semi-tethered swimming test was individually administered in 20 national-competitive swimmers to determine the load maximizing swimming power. In different sessions, participants tested such a load 6 min after a swimming warm-up (SWU) or a dry-land warm-up (DLWU: 3 pull-over reps at 85% of the one-repetition maximum). Kinetic variables (velocity, force, acceleration, impulse, power rate of force development [RFD] and intra-cycle variation), were obtained with a linear encoder through trapezoidal integration regarding time. Kinematic variables (distance, time, stroke-rate and stroke-length), were obtained by video recordings. The differences between protocols were observed by paired-samples t-test (ANOVA). Pearson's coefficient explored correlations between kinetics and kinematics variables; significance was set at P<0.05. RESULTS DLWU increased RFD (34.52±16.55 vs. 31.29±13.70 N/s; Δ=9.35%) and stroke-rate (64.70±9.84 vs. 61.56±7.07 Hz; Δ=5.10%) compared to SWU, but decreased velocity, force, acceleration, impulse and power. During the incremental-load test velocity and power were higher than obtained after SWU (1.21±0.14 vs. 1.17±0.12 m/s; Δ=3.06%), (51.38±14.93 vs. 49.98±15.40 W; Δ=2.72%), suggesting enhancements prompted by the test itself. Correlations between stroke-length with impulse (r=0.76) and power (r=0.75) associated kinetics with kinematics. CONCLUSIONS Potentiation responses were present after the dry-land warm-up. However, swimmers may benefit more from submaximal prolonged conditioning activities such as resisted swimming rather than high-resistance dry-land sets to obtain performance enhancements.
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Affiliation(s)
- Francisco Cuenca-Fernández
- Aquatics Lab, Department of Physical Education and Sports, Faculty of Sport Sciences, University of Granada, Granada, Spain -
| | - Nuno M Batalha
- Department of Sports and Health, University of Evora, Evora, Portugal.,CHRC-UE - Comprehensive Health Research Care, University of Evora, Evora, Portugal
| | - Jesús J Ruiz-Navarro
- Aquatics Lab, Department of Physical Education and Sports, Faculty of Sport Sciences, University of Granada, Granada, Spain
| | - Esther Morales-Ortiz
- Aquatics Lab, Department of Physical Education and Sports, Faculty of Sport Sciences, University of Granada, Granada, Spain
| | - Gracia López-Contreras
- Aquatics Lab, Department of Physical Education and Sports, Faculty of Sport Sciences, University of Granada, Granada, Spain
| | - Raúl Arellano
- Aquatics Lab, Department of Physical Education and Sports, Faculty of Sport Sciences, University of Granada, Granada, Spain
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Padrón R, Ma W, Duno-Miranda S, Koubassova N, Lee KH, Pinto A, Alamo L, Bolaños P, Tsaturyan A, Irving T, Craig R. The myosin interacting-heads motif present in live tarantula muscle explains tetanic and posttetanic phosphorylation mechanisms. Proc Natl Acad Sci U S A 2020; 117:11865-11874. [PMID: 32444484 PMCID: PMC7275770 DOI: 10.1073/pnas.1921312117] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Striated muscle contraction involves sliding of actin thin filaments along myosin thick filaments, controlled by calcium through thin filament activation. In relaxed muscle, the two heads of myosin interact with each other on the filament surface to form the interacting-heads motif (IHM). A key question is how both heads are released from the surface to approach actin and produce force. We used time-resolved synchrotron X-ray diffraction to study tarantula muscle before and after tetani. The patterns showed that the IHM is present in live relaxed muscle. Tetanic contraction produced only a very small backbone elongation, implying that mechanosensing-proposed in vertebrate muscle-is not of primary importance in tarantula. Rather, thick filament activation results from increases in myosin phosphorylation that release a fraction of heads to produce force, with the remainder staying in the ordered IHM configuration. After the tetanus, the released heads slowly recover toward the resting, helically ordered state. During this time the released heads remain close to actin and can quickly rebind, enhancing the force produced by posttetanic twitches, structurally explaining posttetanic potentiation. Taken together, these results suggest that, in addition to stretch activation in insects, two other mechanisms for thick filament activation have evolved to disrupt the interactions that establish the relaxed helices of IHMs: one in invertebrates, by either regulatory light-chain phosphorylation (as in arthropods) or Ca2+-binding (in mollusks, lacking phosphorylation), and another in vertebrates, by mechanosensing.
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Affiliation(s)
- Raúl Padrón
- Division of Cell Biology and Imaging, Department of Radiology, University of Massachusetts Medical School, Worcester, MA 01655;
| | - Weikang Ma
- Biophysics Collaborative Access Team, Department of Biological Sciences, Illinois Institute of Technology, Chicago, IL 60616
| | - Sebastian Duno-Miranda
- Centro de Biología Estructural, Instituto Venezolano de Investigaciones Científicas, Caracas 1020A, Venezuela
| | | | - Kyoung Hwan Lee
- Division of Cell Biology and Imaging, Department of Radiology, University of Massachusetts Medical School, Worcester, MA 01655
| | - Antonio Pinto
- Centro de Biología Estructural, Instituto Venezolano de Investigaciones Científicas, Caracas 1020A, Venezuela
| | - Lorenzo Alamo
- Centro de Biología Estructural, Instituto Venezolano de Investigaciones Científicas, Caracas 1020A, Venezuela
| | - Pura Bolaños
- Centro de Biofísica y Bioquímica, Instituto Venezolano de Investigaciones Científicas, Caracas 1020A, Venezuela
| | - Andrey Tsaturyan
- Institute of Mechanics, Moscow State University, 119992 Moscow, Russia
| | - Thomas Irving
- Biophysics Collaborative Access Team, Department of Biological Sciences, Illinois Institute of Technology, Chicago, IL 60616
| | - Roger Craig
- Division of Cell Biology and Imaging, Department of Radiology, University of Massachusetts Medical School, Worcester, MA 01655
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Kryściak K, Smith IC, Drzymała-Celichowska H, Celichowski J. Initial force production before sag is enhanced by prior contraction followed by a 3-minute rest period in fast motor units of the rat medial gastrocnemius. J Electromyogr Kinesiol 2020; 53:102429. [PMID: 32505088 DOI: 10.1016/j.jelekin.2020.102429] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 04/06/2020] [Accepted: 05/15/2020] [Indexed: 11/28/2022] Open
Abstract
Unfused tetanic contractions evoked in fast motor units exhibit extra-efficient force production at the onset of contraction, an effect called "boost". Boost is diminished in subsequent contractions if there is a short rest period between contractions, but can be re-established with a longer period of rest. We tested the hypothesis that contractile activity and rest could enhance boost-related metrics. Two sets of 3 unfused tetani were evoked 3 min apart in fast fatigable (FF) and fast fatigue-resistant (FR) motor units of the rat medial gastrocnemius. The greatest changes occurred in the first unfused tetanic contractions. Relative to the first contraction in the first set, the first contraction in the second set exhibited higher peak force during boost in a subset of motor units (76% of FF and 48% of FR). Enhanced force during boost was influenced by interaction of slowing of twitch contraction time (up to 20% and 25%, for FF and FR motor units, respectively), half-relaxation time (up to 37% and 49% for FF and FR motor units, respectively), and potentiation of the first twitch (up to 13% and 5% for FF and FR motor units, respectively). Examination of twitches evoked between sets suggested opportunity for greater enhancement of boost with shorter intervening rest periods. The phenomenon of enhanced boost following motor unit activity may interest sports scientists.
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Affiliation(s)
- Katarzyna Kryściak
- Department of Neurobiology, Poznan University of Physical Education, Poland.
| | - Ian C Smith
- Faculty of Kinesiology, University of Calgary, Canada
| | - Hanna Drzymała-Celichowska
- Department of Neurobiology, Poznan University of Physical Education, Poland; Division of Biochemistry, Poznan University of Physical Education, Poland
| | - Jan Celichowski
- Department of Neurobiology, Poznan University of Physical Education, Poland
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Role of Proton Motive Force in Photoinduction of Cytoplasmic Streaming in Vallisneria Mesophyll Cells. PLANTS 2020; 9:plants9030376. [PMID: 32197471 PMCID: PMC7154820 DOI: 10.3390/plants9030376] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 03/03/2020] [Accepted: 03/11/2020] [Indexed: 11/16/2022]
Abstract
In mesophyll cells of the aquatic monocot Vallisneria, red light induces rotational cytoplasmic streaming, which is regulated by the cytoplasmic concentration of Ca2+. Our previous investigations revealed that red light induces Ca2+ efflux across the plasma membrane (PM), and that both the red light-induced cytoplasmic streaming and the Ca2+ efflux are sensitive to vanadate, an inhibitor of P-type ATPases. In this study, pharmacological experiments suggested the involvement of PM H+-ATPase, one of the P-type ATPases, in the photoinduction of cytoplasmic streaming. We hypothesized that red light would activate PM H+-ATPase to generate a large H+ motive force (PMF) in a photosynthesis-dependent manner. We demonstrated that indeed, photosynthesis increased the PMF and induced phosphorylation of the penultimate residue, threonine, of PM H+-ATPase, which is a major activation mechanism of H+-ATPase. The results suggested that a large PMF generated by PM H+-ATPase energizes the Ca2+ efflux across the PM. As expected, we detected a putative Ca2+/H+ exchange activity in PM vesicles isolated from Vallisneria leaves.
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Calcium sensitivity during staircase with sequential incompletely fused contractions. J Muscle Res Cell Motil 2020; 42:59-65. [PMID: 31916128 DOI: 10.1007/s10974-019-09572-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 12/14/2019] [Accepted: 12/27/2019] [Indexed: 10/25/2022]
Abstract
Activity dependent potentiation is thought to result from phosphorylation of the regulatory light chains of myosin, increasing Ca2+ sensitivity. Yet, Ca2+ sensitivity decreases early in a period of intermittent contractions. The purpose of this study was to investigate the early change in Ca2+ sensitivity during intermittent submaximal tetanic contractions. Flexor digitorum brevis muscle fibres were dissected from mice after cervical disarticulation. Fibres were superfused with Tyrode solution at 32 °C. Length was set to yield maximal tetanic force. Indo-1 was microinjected into fibres and allowed to dissipate for 30 min. Fluorescence was measured at 405 and 495 nm wavelength and the ratio was used to estimate [Ca2+]. A control force-Ca2+ relationship was determined with stimulation over a range of frequencies, yielding constants for slope, max force, and half-maximal [Ca2+] (pCa2 +50). Data were collected for sequential contractions at 40 Hz at 2 s intervals. Active force decreased over the first 1-4 contractions then increased. A force-pCa2+ curve was fit to each contraction, using the control values for the Hill slope and max force by adjusting pCa2+50 until the curve passed through the target contraction. Data are presented for three contractions for each fibre: first, maximum shift to the right, and last contraction. There was a significant shift to the right for pCa2+50 (decreased Ca2+ sensitivity), usually early in the series of intermittent contractions, then pCa2 +50 shifted to the left, but remained significantly different from the control value. Although potentiation is associated with increased Ca2+ sensitivity, this increase begins only after Ca2+ sensitivity has decreased and, in most cases, Ca2+ sensitivity does not increase above the control level.
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Lambert M, Claeyssen C, Bastide B, Cieniewski‐Bernard C. O-GlcNAcylation as a regulator of the functional and structural properties of the sarcomere in skeletal muscle: An update review. Acta Physiol (Oxf) 2020; 228:e13301. [PMID: 31108020 DOI: 10.1111/apha.13301] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 05/03/2019] [Accepted: 05/10/2019] [Indexed: 12/15/2022]
Abstract
Although the O-GlcNAcylation process was discovered in 1984, its potential role in the physiology and physiopathology of skeletal muscle only emerged 20 years later. An increasing number of publications strongly support a key role of O-GlcNAcylation in the modulation of important cellular processes which are essential for skeletal muscle functions. Indeed, over a thousand of O-GlcNAcylated proteins have been identified within skeletal muscle since 2004, which belong to various classes of proteins, including sarcomeric proteins. In this review, we focused on these myofibrillar proteins, including contractile and structural proteins. Because of the modification of motor and regulatory proteins, the regulatory myosin light chain (MLC2) is related to several reports that support a key role of O-GlcNAcylation in the fine modulation of calcium activation parameters of skeletal muscle fibres, depending on muscle phenotype and muscle work. In addition, another key function of O-GlcNAcylation has recently emerged in the regulation of organization and reorganization of the sarcomere. Altogether, this data support a key role of O-GlcNAcylation in the homeostasis of sarcomeric cytoskeleton, known to be disturbed in many related muscle disorders.
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Affiliation(s)
- Matthias Lambert
- Univ. Lille, EA 7369 ‐ URePSSS ‐ Unité de Recherche Pluridisciplinaire Sport Santé Société Lille France
| | - Charlotte Claeyssen
- Univ. Lille, EA 7369 ‐ URePSSS ‐ Unité de Recherche Pluridisciplinaire Sport Santé Société Lille France
| | - Bruno Bastide
- Univ. Lille, EA 7369 ‐ URePSSS ‐ Unité de Recherche Pluridisciplinaire Sport Santé Société Lille France
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Blazevich AJ, Babault N. Post-activation Potentiation Versus Post-activation Performance Enhancement in Humans: Historical Perspective, Underlying Mechanisms, and Current Issues. Front Physiol 2019; 10:1359. [PMID: 31736781 PMCID: PMC6838751 DOI: 10.3389/fphys.2019.01359] [Citation(s) in RCA: 217] [Impact Index Per Article: 43.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Accepted: 10/14/2019] [Indexed: 12/31/2022] Open
Abstract
Post-activation potentiation (PAP) is a well-described phenomenon with a short half-life (~28 s) that enhances muscle force production at submaximal levels of calcium saturation (i.e., submaximal levels of muscle activation). It has been largely explained by an increased myosin light chain phosphorylation occurring in type II muscle fibers, and its effects have been quantified in humans by measuring muscle twitch force responses to a bout of muscular activity. However, enhancements in (sometimes maximal) voluntary force production detected several minutes after high-intensity muscle contractions are also observed, which are also most prominent in muscles with a high proportion of type II fibers. This effect has been considered to reflect PAP. Nonetheless, the time course of myosin light chain phosphorylation (underpinning “classic” PAP) rarely matches that of voluntary force enhancement and, unlike PAP, changes in muscle temperature, muscle/cellular water content, and muscle activation may at least partly underpin voluntary force enhancement; this enhancement has thus recently been called post-activation performance enhancement (PAPE) to distinguish it from “classical” PAP. In fact, since PAPE is often undetectable at time points where PAP is maximal (or substantial), some researchers have questioned whether PAP contributes to PAPE under most conditions in vivo in humans. Equally, minimal evidence has been presented that PAP is of significant practical importance in cases where multiple physiological processes have already been upregulated by a preceding, comprehensive, active muscle warm-up. Given that confusion exists with respect to the mechanisms leading to acute enhancement of both electrically evoked (twitch force; PAP) and voluntary (PAPE) muscle function in humans after acute muscle activity, the first purpose of the present narrative review is to recount the history of PAP/PAPE research to locate definitions and determine whether they are the same phenomena. To further investigate the possibility of these phenomena being distinct as well as to better understand their potential functional benefits, possible mechanisms underpinning their effects will be examined in detail. Finally, research design issues will be addressed which might contribute to confusion relating to PAP/PAPE effects, before the contexts in which these phenomena may (or may not) benefit voluntary muscle function are considered.
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Affiliation(s)
- Anthony J Blazevich
- School of Medical and Health Science, Centre for Exercise and Sports Science Research (CESSR), Edith Cowan University, Joondalup, WA, Australia
| | - Nicolas Babault
- Faculty of Sport Sciences, French National Institute of Health and Medical Research (INSERM), Unit 1093 Cognition, Action and Sensorimotor Plasticity, Centre for Performance Expertise, University of Burgundy and Franche-Comté, Dijon, France
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35
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Zimmermann HB, MacIntosh BR, Dal Pupo J. Does postactivation potentiation (PAP) increase voluntary performance? Appl Physiol Nutr Metab 2019; 45:349-356. [PMID: 31557447 DOI: 10.1139/apnm-2019-0406] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The transient increase in torque of an electrically evoked twitch following a voluntary contraction is called postactivation potentiation (PAP). Phosphorylation of myosin regulatory light chains is the most accepted mechanism explaining the enhanced electrically evoked twitch torque. While many authors attribute voluntary postactivation performance enhancement (PAPE) to the positive effects of PAP, few actually confirmed that contraction was indeed potentiated using electrical stimulation (twitch response) at the time that PAPE was measured. Thus, this review aims to investigate if increases in voluntary performance after a conditioning contraction (CC) are related to the PAP phenomenon. For this, studies that confirmed the presence of PAP through an evoked response after a voluntary CC and concurrently evaluated PAPE were reviewed. Some studies reported increases in PAPE when PAP reaches extremely high values. However, PAPE has also been reported when PAP was not present, and unchanged/diminished performance has been identified when PAP was present. This range of observations demonstrates that mechanisms of PAPE are different from mechanisms of PAP. These mechanisms of PAPE still need to be understood and those studying PAPE should not assume that regulatory light chain phosphorylation is the mechanism for such enhanced voluntary performance. Novelty The occurrence of PAP does not necessarily mean that the voluntary performance will be improved. Improvement in voluntary performance is sometimes observed when the PAP level reaches extremely high values. Other mechanisms may be more relevant than that for PAP in the manifestation of acute increases in performance following a conditioning contraction.
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Affiliation(s)
- Haiko Bruno Zimmermann
- Biomechanics Laboratory, Sports Center, Federal University of Santa Catarina, Florianopolis, SC 88040900, Brazil
| | - Brian R MacIntosh
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, AB T2N 1N4, Canada
| | - Juliano Dal Pupo
- Biomechanics Laboratory, Sports Center, Federal University of Santa Catarina, Florianopolis, SC 88040900, Brazil
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36
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Dowling P, Zweyer M, Swandulla D, Ohlendieck K. Characterization of Contractile Proteins from Skeletal Muscle Using Gel-Based Top-Down Proteomics. Proteomes 2019; 7:proteomes7020025. [PMID: 31226838 PMCID: PMC6631179 DOI: 10.3390/proteomes7020025] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 06/14/2019] [Accepted: 06/17/2019] [Indexed: 12/22/2022] Open
Abstract
The mass spectrometric analysis of skeletal muscle proteins has used both peptide-centric and protein-focused approaches. The term 'top-down proteomics' is often used in relation to studying purified proteoforms and their post-translational modifications. Two-dimensional gel electrophoresis, in combination with peptide generation for the identification and characterization of intact proteoforms being present in two-dimensional spots, plays a critical role in specific applications of top-down proteomics. A decisive bioanalytical advantage of gel-based and top-down approaches is the initial bioanalytical focus on intact proteins, which usually enables the swift identification and detailed characterisation of specific proteoforms. In this review, we describe the usage of two-dimensional gel electrophoretic top-down proteomics and related approaches for the systematic analysis of key components of the contractile apparatus, with a special focus on myosin heavy and light chains and their associated regulatory proteins. The detailed biochemical analysis of proteins belonging to the thick and thin skeletal muscle filaments has decisively improved our biochemical understanding of structure-function relationships within the contractile apparatus. Gel-based and top-down proteomics has clearly established a variety of slow and fast isoforms of myosin, troponin and tropomyosin as excellent markers of fibre type specification and dynamic muscle transition processes.
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Affiliation(s)
- Paul Dowling
- Department of Biology, Maynooth University, Maynooth, W23F2H6 Co. Kildare, Ireland.
- MU Human Health Research Institute, Maynooth University, Maynooth, W23F2H6 Co. Kildare, Ireland.
| | - Margit Zweyer
- Institute of Physiology II, University of Bonn, D-53115 Bonn, Germany.
| | - Dieter Swandulla
- Institute of Physiology II, University of Bonn, D-53115 Bonn, Germany.
| | - Kay Ohlendieck
- Department of Biology, Maynooth University, Maynooth, W23F2H6 Co. Kildare, Ireland.
- MU Human Health Research Institute, Maynooth University, Maynooth, W23F2H6 Co. Kildare, Ireland.
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Jiang S, Liu Y, Shen Z, Zhou B, Shen QW. Acetylome profiling reveals extensive involvement of lysine acetylation in the conversion of muscle to meat. J Proteomics 2019; 205:103412. [PMID: 31176012 DOI: 10.1016/j.jprot.2019.103412] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 04/25/2019] [Accepted: 06/04/2019] [Indexed: 12/17/2022]
Abstract
Protein lysine acetylation is an post-translational modification that regulates gene expression, metabolism, cell signaling, and diseases, but its implication in the postmortem (PM) meat quality development is basically unclear. In the present study, a quantitative proteomic analysis was conducted to profile acetylome in porcine muscle within 24 h PM. In total 595 acetylation sites assigned to 163 proteins were identified in porcine muscle, of which 460 sites distributing to 110 proteins significantly changed in acetylation levels in the conversion of muscle to meat. The dynamic acetylation/deacetylaion of muscle proteins was closely associated with critical chemical-biophysical changes in PM muscle. Bioinformatic analysis revealed that protein lysine acetylation likely regulated postmortem meat quality development by regulating glycolysis and muscle pH, cell stress reponse and apoptosis, muscle contraction and rigor mortis, calcium signaling and proteolysis, IMP synthesis and meat flavor development, and even the stability of pigment proteins and meat color. This study provided the first overview of protein lysine acetylation in PM muscle and revealed its significance in the conversion of muscle to meat. Future exploration of the exact role of protein lysine acetylation at specific sites will further our understanding regarding the underlying mechanisms and be helpful for meat quality control. SIGNIFICANCE: This is the first analysis of acetylome in farm animal and postmortem muscle. Our data showed that the dynamic acetylation/deacetylation of muscle proteins was closely related to the postmortem changes of muscle that affect the final quality of raw meat. Proteins related to glucose metabolism and muscle contraction were the two largest clusters of acetylproteins identified in postmortem porcine muscle. Networks of acetylproteins involved in apoptosis, calcium signaling and IMP synthesis were identified in postmortem porcine muscle at the same time. Our results revealed that protein lysine acetylation regulated the conversion of muscle to meat. It likely regulated meat quality development by regulating postmortem glycolysis, mitochondrion initiated cell apoptosis, calcium signaling, rigor mortis, meat flavor compound sysnthesis and meat tenderization. Our study broadened our understanding of the biochemistry regulating the postmortem conversion of muscle to meat and final meat quality development, which may be helpful for future meat quality control.
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Affiliation(s)
- Shengwang Jiang
- College of Food Science and Technology, Hunan Agricultural University, Changsha, Hunan 410128, China
| | - Yisong Liu
- College of Food Science and Technology, Hunan Agricultural University, Changsha, Hunan 410128, China
| | | | - Bing Zhou
- College of Food Science and Technology, Hunan Agricultural University, Changsha, Hunan 410128, China
| | - Qingwu W Shen
- College of Food Science and Technology, Hunan Agricultural University, Changsha, Hunan 410128, China.
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38
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What are the best isometric exercises of muscle potentiation? Eur J Appl Physiol 2019; 119:1029-1039. [PMID: 30734104 DOI: 10.1007/s00421-019-04092-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Accepted: 02/01/2019] [Indexed: 10/27/2022]
Abstract
PURPOSE The aim of this study was to follow post-activation potentiation (PAP), low-frequency fatigue (LFF), metabolic-induced fatigue and post-contractile depression (PCD) in response to different isometric muscle contraction modalities. METHODS Young healthy men (N = 120) were randomly assigned to one of ten exercise modality groups which differed in contraction duration (5-60 s), activation pattern (intermittent or continuous contractions), activation mode (voluntary or stimulated), and intensity [maximal or submaximal (50%)]. Isometric maximal voluntary contraction (MVC), and electrically induced knee extension torque were measured at baseline and at regular intervals for 60 min after exercise. RESULTS Muscle contraction modalities involving 5 s MVC were the most effective for PAP, whereas the lowest PAP effectiveness was found after the 12 × 5-MVC modality. After all of the 5-15 s MVC and 6 × 5-MVC protocols, the potentiation of the twitch rate was significantly higher than that recorded after continuous 30-60 s protocols (P < 0.001). Tetanic maximal torque (100 Hz) potentiation occurred 5 min after 15-30 s repetitive MVC modalities and after modality involving 15 electrical stimuli (P < 0.05). CONCLUSIONS The findings demonstrate that post-activation potentiation was most effective after brief duration continuous and repetitive MVC protocols. To understand the resultant warm-up of motor performance, it is necessary to recognize the coexistence of muscle PAP, tetanic maximal force potentiation, rapid recovery of metabolic muscle, and central muscle activation processes, as well as prolonged LFF and prolonged PCD.
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39
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Abbes Z, Chamari K, Mujika I, Tabben M, Bibi KW, Hussein AM, Martin C, Haddad M. Do Thirty-Second Post-activation Potentiation Exercises Improve the 50-m Freestyle Sprint Performance in Adolescent Swimmers? Front Physiol 2018; 9:1464. [PMID: 30459632 PMCID: PMC6232934 DOI: 10.3389/fphys.2018.01464] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 09/27/2018] [Indexed: 11/13/2022] Open
Abstract
Objectives: The purpose of the study was to investigate performance, biomechanical, physiological, and psychophysiological effects of a simple and easily organized post-activation potentiation (PAP) re-warm-up performed before a 50-m freestyle swimming sprint. Methods: Regional level male adolescent swimmers [age: 13.0 ± 2.0 years; (min 11 years – max 15 years)] performed four trial conditions (three experimental, one control) on different days. The control trial involved a standardized 1200-m warm-up followed by 30 min of rest and a maximal 50-m freestyle swimming sprint. The experimental trials involved the same protocol but added a PAP component after a 20-min rest (10 min pre-50-m): The different PAP component involved the subjects in completing a 30-s maximal effort of: (1) push-ups (PU – upper body), (2) squats (SQ – lower body), and (3) burpees (BP – lower and upper body). Performance (time-trial), biomechanical (stroke length, stroke frequency), physiological (blood lactate concentrations, heart rate), and psychophysiological (ratings of perceived exertion) variables were collected. Results: The results demonstrated that the PAP protocols used in this investigation had no effect on swimming performance. Before the 50-m swimming sprint, the lactate values were significantly higher after the PU, BP, and SQ PAP loads compared to the control condition [P(CC-PU) = 0.02; P(CC-BP) = 0.01; P(CC-SQ) = 0.04]. For Lactate values, a significant and large effect of experimental condition compared to control condition was found (p < 0.05, η2 = 0.68). At 1 min after the 50-m time trial, significant differences were observed between the control condition and the different PAP loads [P(CC-PU) = 0.01; P(CC-BP) = 0.04; P(CC-SQ) = 0.01]. At 3 min after the 50-m sprint, significant differences were found between the control condition and the PU and SQ PAP loads [P(CC-PU) = 0.018; P(CC-SQ) = 0.008, respectively]. Additionally, a significant and large effect of experimental condition was found at 1 and 3 min after the 50-m swimming sprint (p < 0.05, η2(1 min) = 0.73; η2(3 min) = 0.59). There were medium sized but non-significant effects of interaction between the conditions, was illustrated for the mean HR values in response to the different conditions (p > 0.05; η2 = 0.083). Conclusion: None of the three PAP protocols showed any significant improvement in performance, biomechanical, physiological, and psychophysiological variables before, during and after the 50-m swimming time-trial. Further studies are warranted to investigate ways to improve swimming performance with simple body mass exercises performed in-between the end of pool warm-up and race start.
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Affiliation(s)
- Zied Abbes
- Interuniversity Laboratory of Human Movement Biology EA7424, University of Lyon - University Claude Bernard Lyon 1, Lyon, France
| | - Karim Chamari
- AHP Research Centre, ASPETAR, Qatar Orthopaedic and Sports Medicine Hospital, Doha, Qatar
| | - Iñigo Mujika
- Department of Physiology, Faculty of Medicine and Nursing, University of the Basque Country, Leioa, Spain.,Exercise Science Laboratory, School of Kinesiology, Faculty of Medicine, Universidad Finis Terrae, Santiago, Chile
| | - Montassar Tabben
- ASPREV Department, ASPETAR, Qatar Orthopaedic and Sports Medicine Hospital, Doha, Qatar
| | - Khalid W Bibi
- Physical Education Program, College of Education, Qatar University, Doha, Qatar
| | - Ali Mostafa Hussein
- Sport Science Program, College of Arts and Sciences, Qatar University, Doha, Qatar
| | - Cyril Martin
- Interuniversity Laboratory of Human Movement Biology EA7424, University of Lyon - University Claude Bernard Lyon 1, Lyon, France
| | - Monoem Haddad
- Sport Science Program, College of Arts and Sciences, Qatar University, Doha, Qatar
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40
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Coggan AR, Peterson LR. Dietary Nitrate Enhances the Contractile Properties of Human Skeletal Muscle. Exerc Sport Sci Rev 2018; 46:254-261. [PMID: 30001275 PMCID: PMC6138552 DOI: 10.1249/jes.0000000000000167] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
We review recent studies of the effects of dietary nitrate on human muscle contractile function and discuss possible underlying mechanisms. Dietary nitrate, a source of nitric oxide (NO), improves the contractile properties of human muscle. We present the hypothesis that this is due to nitrosylation of the ryanodine receptor and increased NO signaling via the soluble guanyl cyclase-cyclic guanosine monophosphate-protein kinase G pathway, which together increase the free intracellular Ca2+ concentration along with the Ca2+ sensitivity of the myofilaments themselves.
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Affiliation(s)
- Andrew R Coggan
- Departments of Kinesiology and.,Cellular and Integrative Physiology, Indiana University Purdue University Indianapolis, Indianapolis, IN
| | - Linda R Peterson
- Medicine and.,Radiology, Washington University School of Medicine, St. Louis, MO
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41
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Wang L, Geist J, Grogan A, Hu LYR, Kontrogianni-Konstantopoulos A. Thick Filament Protein Network, Functions, and Disease Association. Compr Physiol 2018; 8:631-709. [PMID: 29687901 PMCID: PMC6404781 DOI: 10.1002/cphy.c170023] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Sarcomeres consist of highly ordered arrays of thick myosin and thin actin filaments along with accessory proteins. Thick filaments occupy the center of sarcomeres where they partially overlap with thin filaments. The sliding of thick filaments past thin filaments is a highly regulated process that occurs in an ATP-dependent manner driving muscle contraction. In addition to myosin that makes up the backbone of the thick filament, four other proteins which are intimately bound to the thick filament, myosin binding protein-C, titin, myomesin, and obscurin play important structural and regulatory roles. Consistent with this, mutations in the respective genes have been associated with idiopathic and congenital forms of skeletal and cardiac myopathies. In this review, we aim to summarize our current knowledge on the molecular structure, subcellular localization, interacting partners, function, modulation via posttranslational modifications, and disease involvement of these five major proteins that comprise the thick filament of striated muscle cells. © 2018 American Physiological Society. Compr Physiol 8:631-709, 2018.
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Affiliation(s)
- Li Wang
- Department of Biochemistry and Molecular Biology, University of Maryland, Baltimore, Maryland, USA
| | - Janelle Geist
- Department of Biochemistry and Molecular Biology, University of Maryland, Baltimore, Maryland, USA
| | - Alyssa Grogan
- Department of Biochemistry and Molecular Biology, University of Maryland, Baltimore, Maryland, USA
| | - Li-Yen R. Hu
- Department of Biochemistry and Molecular Biology, University of Maryland, Baltimore, Maryland, USA
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42
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Bunda J, Gittings W, Vandenboom R. Myosin phosphorylation improves contractile economy of mouse fast skeletal muscle during staircase potentiation. ACTA ACUST UNITED AC 2018; 221:jeb.167718. [PMID: 29361581 DOI: 10.1242/jeb.167718] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Accepted: 12/31/2017] [Indexed: 01/12/2023]
Abstract
Phosphorylation of the myosin regulatory light chain (RLC) by skeletal myosin light chain kinase (skMLCK) potentiates rodent fast twitch muscle but is an ATP-requiring process. Our objective was to investigate the effect of skMLCK-catalyzed RLC phosphorylation on the energetic cost of contraction and the contractile economy (ratio of mechanical output to metabolic input) of mouse fast twitch muscle in vitro (25°C). To this end, extensor digitorum longus (EDL) muscles from wild-type (WT) and from skMLCK-devoid (skMLCK-/-) mice were subjected to repetitive low-frequency stimulation (10 Hz for 15 s) to produce staircase potentiation of isometric twitch force, after which muscles were quick frozen for determination of high-energy phosphate consumption (HEPC). During stimulation, WT muscles displayed significant potentiation of isometric twitch force while skMLCK-/- muscles did not (i.e. 23% versus 5% change, respectively). Consistent with this, RLC phosphorylation was increased ∼3.5-fold from the unstimulated control value in WT but not in skMLCK-/- muscles. Despite these differences, the HEPC of WT muscles was not greater than that of skMLCK-/- muscles. As a result of the increased contractile output relative to HEPC, the calculated contractile economy of WT muscles was greater than that of skMLCK-/- muscles. Thus, our results suggest that skMLCK-catalyzed phosphorylation of the myosin RLC increases the contractile economy of WT mouse EDL muscle compared with skMLCK-/- muscles without RLC phosphorylation.
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Affiliation(s)
- Jordan Bunda
- Centre for Bone and Muscle Health, Faculty of Applied Health Sciences, Brock University, St Catharines, ON L2S 3A1, Canada
| | - William Gittings
- Centre for Bone and Muscle Health, Faculty of Applied Health Sciences, Brock University, St Catharines, ON L2S 3A1, Canada
| | - Rene Vandenboom
- Centre for Bone and Muscle Health, Faculty of Applied Health Sciences, Brock University, St Catharines, ON L2S 3A1, Canada
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43
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Alamo L, Koubassova N, Pinto A, Gillilan R, Tsaturyan A, Padrón R. Lessons from a tarantula: new insights into muscle thick filament and myosin interacting-heads motif structure and function. Biophys Rev 2017; 9:461-480. [PMID: 28871556 DOI: 10.1007/s12551-017-0295-1] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Accepted: 07/27/2017] [Indexed: 12/13/2022] Open
Abstract
The tarantula skeletal muscle X-ray diffraction pattern suggested that the myosin heads were helically arranged on the thick filaments. Electron microscopy (EM) of negatively stained relaxed tarantula thick filaments revealed four helices of heads allowing a helical 3D reconstruction. Due to its low resolution (5.0 nm), the unambiguous interpretation of densities of both heads was not possible. A resolution increase up to 2.5 nm, achieved by cryo-EM of frozen-hydrated relaxed thick filaments and an iterative helical real space reconstruction, allowed the resolving of both heads. The two heads, "free" and "blocked", formed an asymmetric structure named the "interacting-heads motif" (IHM) which explained relaxation by self-inhibition of both heads ATPases. This finding made tarantula an exemplar system for thick filament structure and function studies. Heads were shown to be released and disordered by Ca2+-activation through myosin regulatory light chain phosphorylation, leading to EM, small angle X-ray diffraction and scattering, and spectroscopic and biochemical studies of the IHM structure and function. The results from these studies have consequent implications for understanding and explaining myosin super-relaxed state and thick filament activation and regulation. A cooperative phosphorylation mechanism for activation in tarantula skeletal muscle, involving swaying constitutively Ser35 mono-phosphorylated free heads, explains super-relaxation, force potentiation and post-tetanic potentiation through Ser45 mono-phosphorylated blocked heads. Based on this mechanism, we propose a swaying-swinging, tilting crossbridge-sliding filament for tarantula muscle contraction.
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Affiliation(s)
- Lorenzo Alamo
- Centro de Biología Estructural "Humberto Fernández-Morán", Instituto Venezolano de Investigaciones Científicas (IVIC), Apdo. 20632, Caracas, 1020A, Venezuela
| | - Natalia Koubassova
- Institute of Mechanics, Moscow State University, Mitchurinsky prosp. 1, Moscow, 119992, Russia
| | - Antonio Pinto
- Centro de Biología Estructural "Humberto Fernández-Morán", Instituto Venezolano de Investigaciones Científicas (IVIC), Apdo. 20632, Caracas, 1020A, Venezuela
| | - Richard Gillilan
- Macromolecular Diffraction Facility, Cornell High Energy Synchrotron Source, Ithaca, NY, USA
| | - Andrey Tsaturyan
- Institute of Mechanics, Moscow State University, Mitchurinsky prosp. 1, Moscow, 119992, Russia
| | - Raúl Padrón
- Centro de Biología Estructural "Humberto Fernández-Morán", Instituto Venezolano de Investigaciones Científicas (IVIC), Apdo. 20632, Caracas, 1020A, Venezuela.
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44
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Trivedi DV, Adhikari AS, Sarkar SS, Ruppel KM, Spudich JA. Hypertrophic cardiomyopathy and the myosin mesa: viewing an old disease in a new light. Biophys Rev 2017; 10:27-48. [PMID: 28717924 PMCID: PMC5803174 DOI: 10.1007/s12551-017-0274-6] [Citation(s) in RCA: 105] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Accepted: 06/12/2017] [Indexed: 12/15/2022] Open
Abstract
The sarcomere is an exquisitely designed apparatus that is capable of generating force, which in the case of the heart results in the pumping of blood throughout the body. At the molecular level, an ATP-dependent interaction of myosin with actin drives the contraction and force generation of the sarcomere. Over the past six decades, work on muscle has yielded tremendous insights into the workings of the sarcomeric system. We now stand on the cusp where the acquired knowledge of how the sarcomere contracts and how that contraction is regulated can be extended to an understanding of the molecular mechanisms of sarcomeric diseases, such as hypertrophic cardiomyopathy (HCM). In this review we present a picture that combines current knowledge of the myosin mesa, the sequestered state of myosin heads on the thick filament, known as the interacting-heads motif (IHM), their possible interaction with myosin binding protein C (MyBP-C) and how these interactions can be abrogated leading to hyper-contractility, a key clinical manifestation of HCM. We discuss the structural and functional basis of the IHM state of the myosin heads and identify HCM-causing mutations that can directly impact the equilibrium between the 'on state' of the myosin heads (the open state) and the IHM 'off state'. We also hypothesize a role of MyBP-C in helping to maintain myosin heads in the IHM state on the thick filament, allowing release in a graded manner upon adrenergic stimulation. By viewing clinical hyper-contractility as the result of the destabilization of the IHM state, our aim is to view an old disease in a new light.
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Affiliation(s)
- Darshan V Trivedi
- Department of Biochemistry, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Arjun S Adhikari
- Department of Biochemistry, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Saswata S Sarkar
- Department of Biochemistry, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Kathleen M Ruppel
- Department of Biochemistry, Stanford University School of Medicine, Stanford, CA, 94305, USA. .,Department of Pediatrics (Cardiology), Stanford University School of Medicine, Stanford, CA, 94305, USA.
| | - James A Spudich
- Department of Biochemistry, Stanford University School of Medicine, Stanford, CA, 94305, USA.
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45
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Cuenca-Fernández F, Smith IC, Jordan MJ, MacIntosh BR, López-Contreras G, Arellano R, Herzog W. Nonlocalized postactivation performance enhancement (PAPE) effects in trained athletes: a pilot study. Appl Physiol Nutr Metab 2017; 42:1122-1125. [PMID: 28675792 DOI: 10.1139/apnm-2017-0217] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Fifteen trained athletes were assessed for postactivation performance enhancement (PAPE) of squat jumps (SJs) and power push-ups (PPUs) following upper body activation, lower body activation, upper and lower body activation, and rest. SJ improved similarly across all 4 conditions. PPU could not be assessed. Since the test protocol of SJ and PPU involved upper and lower body activation and caused PAPE in SJ, future work is required to determine if a nonlocalized PAPE effect exists.
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Affiliation(s)
- Francisco Cuenca-Fernández
- a Department of Physical Education and Sport, Faculty of Sport Sciences. University of Granada, Granada 18011, Spain
| | - Ian C Smith
- b Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, AB T2N 1N4, Canada
| | - Matthew J Jordan
- b Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, AB T2N 1N4, Canada
| | - Brian R MacIntosh
- b Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, AB T2N 1N4, Canada
| | - Gracia López-Contreras
- a Department of Physical Education and Sport, Faculty of Sport Sciences. University of Granada, Granada 18011, Spain
| | - Raúl Arellano
- a Department of Physical Education and Sport, Faculty of Sport Sciences. University of Granada, Granada 18011, Spain
| | - Walter Herzog
- b Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, AB T2N 1N4, Canada
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46
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Gittings W, Bunda J, Vandenboom R. Shortening speed dependent force potentiation is attenuated but not eliminated in skeletal muscles without myosin phosphorylation. J Muscle Res Cell Motil 2017; 38:157-162. [PMID: 28251466 DOI: 10.1007/s10974-017-9465-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Accepted: 02/02/2017] [Indexed: 01/08/2023]
Abstract
We investigated the influence of shortening speed on concentric force potentiation at different frequencies in muscles devoid of skeletal myosin light chain kinase (skMLCK-/-) and unable to phosphorylate myosin. EDL muscles from skMLCK-/- mice were activated in vitro (25 °C) across a range of stimulation frequencies (10-100 Hz) during shortening ramps at 0.10, 0.30, or 0.50 of maximum shortening velocity (Vmax) before and after a potentiating stimulus (PS). When collapsed across all frequencies, the PS increased relative (post/pre) concentric force to 1.27 ± 0.02 and 1.17 ± 0.02 of pre-PS values at 0.50 and 0.30 Vmax, respectively (n = 4, P < 0.05 for all speeds). In addition, potentiation was significantly greater at low and intermediate-than at high stimulus frequencies at both speeds. In contrast, during shortening at 0.10 Vmax, a posttetanic depression was observed as mean concentric forces were reduced to 0.85 ± 0.02 of pre-PS values. Thus, although reduced compared to published values for wildtype muscles (Gittings et al., J Muscle Res Cell Motil 33:359-368, 2012), skMLCK-/- muscles displayed a speed dependent potentiation of concentric force during moderate and fast shortening speed at all frequencies tested. Our data support the presence of a myosin phosphorylation-independent mechanism(s) for concentric force potentiation at moderate speeds of shortening, and also suggests that myosin phosphorylation may be necessary to prevent the concentric force depression that may be present at slow speeds of shortening. Although additive in nature, further work is needed to parse out the relative influence of myosin phosphorylation-independent and dependent potentiation mechanisms on wildtype contractile function during dynamic conditions.
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Affiliation(s)
- William Gittings
- Centre for Bone and Muscle Health, Brock University, 274 Walker Complex, 1812 Sir Isaac Brock Way, St. Catharines, ON, L2S 3A1, Canada
| | - Jordan Bunda
- Centre for Bone and Muscle Health, Brock University, 274 Walker Complex, 1812 Sir Isaac Brock Way, St. Catharines, ON, L2S 3A1, Canada
| | - Rene Vandenboom
- Centre for Bone and Muscle Health, Brock University, 274 Walker Complex, 1812 Sir Isaac Brock Way, St. Catharines, ON, L2S 3A1, Canada.
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