Joshua P Nederveen

McMaster University | McMaster

Trophoblast differentiation is a crucial process in the formation of the placenta where cytotrophoblasts (CTs) differentiate and fuse to form the syncytiotrophoblast (ST). The bioactive components of cannabis, such as Δ9-THC, are known to disrupt trophoblast differentiation and fusion, as well as mitochondrial dynamics and respiration. However, les...

Background: Despite the growing recognition of the obesity crisis, its rates continue to rise. The current first-line therapies, such as dietary changes, energy restriction, and physical activity, are typically met with poor adherence. Novel nutritional interventions can address the root causes of obesity, including mitochondrial dysfunction, and...

Objective: Metabolic Syndrome (MetS) affects hundreds of millions of individuals and constitutes a major cause of morbidity and mortality worldwide. Obesity is believed to be at the core of metabolic abnormalities associated with MetS, including dyslipidemia, insulin resistance, fatty liver disease and vascular dysfunction. Although previous studi...

The age‐related loss of skeletal muscle mass and functionality, known as sarcopenia, is a critical risk factor for morbidity and all‐cause mortality. Resistance exercise training (RET) is the primary countermeasure to fight sarcopenia and ageing. Altered intercellular communication is a hallmark of ageing, which is not well elucidated. Circulating...

Radiation exposure is an undeniable health threat encountered in various occupations and procedures. High energy waves in ionizing radiation cause DNA damage and induce reactive oxygen species (ROS) production, which further exacerbate DNA, protein, and lipid damage, increasing risk of mutations. Although endogenous antioxidants such as superoxide...

Aging is accompanied by a loss of muscle mass and function, termed sarcopenia, which causes numerous morbidities and economic burdens in human populations. Mechanisms implicated in age-related sarcopenia or frailty include inflammation, muscle stem cell depletion, mitochondrial dysfunction, and loss of motor neurons, but whether there are key drive...

Skeletal muscle is maintained and repaired by sub‐laminar, Pax7‐expressing satellite cells. However, recent mouse investigations have described a second myogenic progenitor population that resides within the myofiber interstitium and expresses the transcription factor Twist2. Twist2‐expressing cells exclusively repair and maintain type IIx/b muscle...

Fatty acids are vital for the survival of eukaryotes, but when present in excess can have deleterious consequences. The AMP-activated protein kinase (AMPK) is an important regulator of multiple branches of metabolism. Studies in purified enzyme preparations and cultured cells have shown that AMPK is allosterically activated by small molecules as we...

Purpose: To investigate the modulation of circulating exosome-like extracellular vesicles (ELVs) after 6 weeks of sprint interval training (SIT) at sea-level, 2,000 m, 3,000 m and 4,000 m. Methods: Thirty trained endurance male athletes (18-35y) participated in a six-week SIT program (30 s all-out sprint, 4 min 30 s recovery; 4-9 repetitions, 2...

Alglucosidase alpha is an orphan drug approved for enzyme replacement therapy (ERT) in Pompe disease (PD); however, its efficacy is limited in skeletal muscle because of a partial blockage of autophagic flux that hinders intracellular trafficking and enzyme delivery. Adjunctive therapies that enhance autophagic flux and protect mitochondrial integr...

Background: Myotonic dystrophy type 1 (DM1) is a complex life-limiting neuromuscular disorder characterized by severe skeletal muscle atrophy, weakness, and cardio-respiratory defects. Exercised DM1 mice exhibit numerous physiological benefits that are underpinned by reduced CUG foci and improved alternative splicing. However, the efficacy of phys...

High aerobic endurance capacity can be acquired by training and/or inherited. Aerobic exercise training (AET) and aging are linked to altered gut microbiome composition, but it is unknown if the environmental stress of exercise and host genetics that predispose for higher exercise capacity have similar effects on the gut microbiome during aging. We...

Purpose: To investigate exosome-like vesicle (ELV) plasma concentrations and markers of multivesicular body (MVB) biogenesis in skeletal muscle in response to acute exercise. Methods: Seventeen healthy (BMI: 23.5±0.5kg·m-2) and fifteen prediabetic (BMI: 27.3±1.2kg·m-2) men were randomly assigned to two groups performing an acute cycling bout in...

Aims/hypothesis This study interrogated mitochondrial respiratory function and content in skeletal muscle biopsies of healthy adults between 30 and 72 years old with and without uncomplicated type 1 diabetes. Methods Participants (12 women/nine men) with type 1 diabetes (48 ± 11 years of age), without overt complications, were matched for age, sex...

We investigated the effects of a novel multi-ingredient supplement comprised of polyphenol antioxidants and compounds known to facilitate mitochondrial function and metabolic enhancement (ME) in a mouse model of obesity. In this study, 6-week-old male C57/BL6J mice were placed on a high-fat diet (HFD; ~60% fat) for 6 weeks, with subsequent allocati...

Satellite cells are essential for skeletal muscle regeneration, repair, and adaptation. The activity of satellite cells is influenced by their interactions with muscle-resident endothelial cells. We postulate that the microvascular network between muscle fibers plays a critical role in satellite cell function. Exercise-induced angiogenesis can miti...

The benefits of exercise on health and longevity are well-established, and evidence suggests that these effects are partially driven by a spectrum of bioactive molecules released into circulation during exercise (e.g., exercise factors or ‘exerkines’). Recently, extracellular vesicles (EVs), including microvesicles (MVs) and exosomes or exosome-lik...

Aging is accompanied by a loss of muscle mass and function, termed sarcopenia, which causes numerous morbidities and economic burdens in human populations. Mechanisms implicated in age-related sarcopenia include inflammation, muscle stem cell depletion, mitochondrial dysfunction and loss of motor neurons, but whether there are key drivers of sarcop...

Old age is associated with lower physical activity levels, suboptimal protein intake, and desensitization to anabolic stimuli, predisposing for age-related muscle loss (sarcopenia). Although resistance exercise (RE) and protein supplementation partially protect against sarcopenia under controlled conditions, the efficacy of home-based, unsupervised...

Skeletal muscle satellite cell (SC) function and responsiveness is regulated, in part, through interactions within the niche, in which they reside. Evidence suggests that structural changes occur in the SC niche as a function of aging. In the present study, we investigated the impact of aging on SC niche properties. Muscle biopsies were obtained fr...

[This corrects the article DOI: 10.1371/journal.pone.0210863.].

The percutaneous muscle biopsy procedure is an invaluable tool for characterizing skeletal muscle and capillarization. Little is known about methodological or biological variation stemming from the technique in heterogeneous muscle. Five muscle biopsies were taken from the vastus lateralis of a group of young men (n = 29, 22 ± 1 years) over a 96-h...

IntroductionHematopoietic stem and progenitor cells (HSPC) are responsible for the reconstitution of blood cells and thought to contribute to peripheral tissue repair. Following acute exercise in young adults, HSPC are mobilized from their niche in bone marrow into circulation, however the kinetics of mobilization following exercise is not well und...

Muscle satellite cell (SC) regulation is a complex process involving many key signalling molecules. Recently, the neurotrophin brain-derived neurotropic factor (BDNF) has implicated in SC regulation in animals. To date, little is known regarding the role of BDNF in human SC function in vivo. Twenty-nine males (age, 21 ± 0.5 years) participated in t...

Skeletal muscle satellite cells (SC) play an important role in muscle repair following injury. The regulation of SC activity is governed by myogenic regulatory factors (MRF), including MyoD, Myf5, myogenin, and MRF4. The mRNA expression of these MRF in humans following muscle damage has been predominately measured in whole muscle homogenates. Wheth...

Prelaboratory tasks are used to facilitate learning and introduce and provide context for laboratory work. The application of first-person perspective (FPP) technology may provide interesting new approaches to providing prelaboratory preparation. However, there is limited knowledge as to whether this perspective is useful or enjoyable for students...

Three theoretical models have been proposed to explain lifespan extension resulting from exposure to extreme conditions in microscopic animals: individuals become completely dormant and stop aging, continue to age or age but at a diminished rate. Here we show that the earliest life history stages, embryonic cell divisions, in the tardigrade species...

Biological aging is associated with progressive damage accumulation, loss of organ reserves, and systemic inflammation ('inflammaging'), which predispose for a wide spectrum of chronic diseases, including several types of cancer. In contrast, aerobic exercise training (AET) reduces inflammation, lowers all-cause mortality, and enhances both health...

Cytokine and chemokine data. Lifelong aerobic exercise training (AET) dampens inflammaging in old C57BL/J6 mice. Serum cytokine and chemokine concentrations are reported in pg/mL and expressed as group means ± SE. Each sample consisted of serum from one or two mice within the same experimental condition. All samples were run in duplicate. (DOC)

3-way ANOVA table for cytokine and chemokine data. (DOC)

Myokine data. Lifelong aerobic exercise training (AET) mitigates serum SPARC levels in old C57BL/J6 mice. Serum myokine concentrations are in pg/mL and expressed as group means ± SE. Each sample consisted of serum from one or two mice within the same experimental condition. All samples were run in duplicate. (DOC)

3-way ANOVA table for myokine data. (DOC)

Serum exerkines in acutely exercised, young C57BL/J6 mice (Y-CON2 vs. Y-CON-EX2). Serum exerkine concentrations are reported in pg/mL and expressed as group means ± SE. Each sample consisted of serum from one or two mice within the same experimental condition. All samples were run in duplicate. (DOC)

Quantitative PCR methods. (DOCX)

Quadriceps mRNA expression of regulators of the innate immune response and cell cycle progression. Group columns that are significantly different do not share the same letter(s) (P ≤ 0.05). (TIFF)

Functional data. Lifelong aerobic exercise training (AET) mitigates age-associated dynapenia and aerobic deconditioning in C57BL/J6 mice. *Significant effects of aging, †lifelong aerobic exercise training, and ‡gender (P ≤ 0.05). (DOC)

Voluntary running-wheel distances. Voluntary running-wheel distances decreased with aging in C57BL/J6 mice. Groups that do not share the same letter(s) are statistically different (P ≤ 0.05). (DOC)

Morphological data. Lifelong aerobic exercise training (AET) mitigates age-associated muscle loss and testicular atrophy in C57BL/J6 mice. Age-associated organ wasting was isolated to fast-twitch muscles and testicles (test.), while slow-twitch muscles (solues; sol.) and other internal organs (heart, brain, liver, kidney, spleen, and lungs) were la...

Exercise positively impacts mood and symptoms of depression; however, the mechanisms underlying these effects are not fully understood. Recent evidence highlights a potential role for skeletal muscle-derived transcription factors to influence tryptophan metabolism, along the kynurenine pathway, which has important implications in depression. This h...

Key points Skeletal muscle stem cells, termed satellite cells, play a crucial role in repair and remodelling of muscle in response to exercise An age‐related decline in satellite cell number and/or function has been hypothesized to be a key factor in the development of sarcopenia and/or the blunted muscle fibre adaptive response to prolonged exerci...

Background Nutritional supplementation can have beneficial effects on body composition, strength, and function in older adults. However, whether the response of satellite cells can be altered by nutritional supplementation in older adults remains unknown. Objective We assessed whether a multi-ingredient protein-based supplement taken over a prolon...

Satellite cells are indispensable for skeletal muscle repair and regeneration and are associated with muscle growth in humans. Aerobic exercise training results in improved skeletal muscle health also translating to an increase in satellite cell pool activation. We postulate that aerobic exercise improves satellite cell function in skeletal muscle.

Skeletal muscle satellite cells (SC) play an important role in muscle repair following injury. The regulation of SC activity is governed by myogenic regulatory factors (MRF), including MyoD, Myf5, myogenin and MRF4. The mRNA expression of these MRF in humans following muscle damage has been predominately measured in whole muscle homogenate. Whether...

Skeletal muscle satellite cells (SC) are important for maintenance and repair of myofibers. SC function and responsiveness is regulated, at least in part, through interactions with niche components in which they reside. Recent evidence suggests that structural changes occur in the SC niche as a function of aging. In the present study, we aimed to i...

High-intensity interval training (HIIT) enhances skeletal muscle oxygen delivery and utilization but data are limited regarding fiber-specific adaptations in humans. We examined the effect of 18 sessions of HIIT (10 × 60-sec cycling intervals at ~90% HRmax, interspersed by 60-sec of recovery) over 6 weeks on markers of microvascular density and oxi...

Satellite cells (SC) are associated with skeletal muscle remodelling after muscle damage and/or extensive hypertrophy resulting from resistance training (RT). We recently reported that early increases in muscle protein synthesis (MPS) during RT appear to be directed toward muscle damage repair, but MPS contributes to hypertrophy with progressive mu...

Key points: Skeletal muscle stem cells (satellite cells) play a crucial role in repair and remodelling of muscle in response to exercise. Satellite cells are in close spatial proximity to muscle capillaries and therefore may be influenced by them. In this study, we describe the activation and expansion of the satellite cell pool in response to ecc...

Aging gradually renders bone marrow hematopoietically inactive. Endurance exercise reverses this phenotype in young mice. Here, we determine the effects in aged mice. Twenty-two month old mice (n = 6) underwent a progressive exercise training protocol. In appendicular bones, marrow cellularity increased by 51% (p < 0.05) and marrow CFU, CFU-GM, and...

Purpose of Review Skeletal muscle satellite cells (SC) play an important role in the adaptation, repair, and maintenance of muscle. These resident muscle stem cells are regulated by a series of transcription factors known as myogenic regulator factors that orchestrate SC progression from the quiescent state through activation, proliferation, and di...

Flow-mediated dilation (FMD) is calculated as the greatest percent change in arterial diameter following an ischaemic challenge. This Traditional %FMD calculation is thought to have statistical bias towards baseline diameter (Dbase), which is reduced by allometric scaling. This study examined whether allometric scaling FMD influenced the difference...

To investigate the association between muscle fiber capillarization and indices of insulin sensitivity in healthy older adults. A skeletal muscle biopsy was taken from the m vastus lateralis of 22 healthy (nondiabetic) male older adults. In addition, all participants underwent an Oral Glucose Tolerance Test (OGTT). Muscle fiber capillarization was...

Supporting info item

New & noteworthy: Here we demonstrate for the first time that mobilization of hematopoietic stem cells (HSCs) through exercise is intensity dependent, with the greatest mobilization occurring immediately after high-intensity exercise. As well, we show that exercise is a general stimulus for mobilization: increases in specific HSC populations are r...

Skeletal muscle satellite cells (SC) play an important role in muscle adaptation. In untrained individuals, SC content and activation status has been observed to increase in response to a single bout of exercise. Muscle fiber characteristics change considerably when resistance exercise is performed chronically, but whether training status affects t...

We thank Tremblay and King for their interest in our publication (McLay et al., 2016a), which has since been followed up with studies by McLay et al. (McLay et al., 2016c, 2016b). In these studies, it is suggested that the near-infrared spectroscopy (NIRS)-derived measure of tissue oxygen saturation (StO2), specifically the reperfusion rate (Slope...

Sarcopenia is the age-related loss of skeletal muscle mass and strength. Ultimately, sarcopenia results in the loss of independence, which imposes a large financial burden on healthcare systems worldwide. A critical facet of sarcopenia is the diminished ability for aged muscle to regenerate, repair and remodel. Over the years, research has focused...

We examined the effect of heavy-intensity ‘priming’ exercise on the rate of adjustment of pulmonary O2 uptake (τV̇O2p) initiated from elevated intensities. Fourteen men (separated into two groups: τV̇O2p ≤ 25 s [Fast] or τV̇O2p > 25 s [Slow]) completed step-transitions from 20W-to-45%lactate threshold (LT; lower-step, LS) and 45%-to-90%LT (upper-st...

Background: Adequate muscle fibre perfusion is critical for the maintenance of muscle mass; it is essential in the rapid delivery of oxygen, nutrients and growth factors to the muscle, stimulating muscle fibre growth. Muscle fibre capillarization is known to decrease substantially with advancing age. However, whether (relative) low muscle fibre ca...

to the editor: Arentson-Lantz et al. ([1][1]) report that 14 days of bed rest (BR) induces a profound decline in muscle strength (−13%) and fiber cross-sectional area (CSA) (−24%) in middle-aged adults. More importantly, they report that short-term disuse-induced muscle fiber atrophy is

Skeletal muscle possesses the ability to regenerate after injury, but this ability is impaired or delayed with aging. Regardless of age, muscle retains the ability to positively respond to stimuli, such as exercise. We examined whether exercise is able to improve regenerative response in skeletal muscle of aged mice. Twenty-two-mo-old male C57Bl/6J...

Near-infrared spectroscopy (NIRS)-derived measures of tissue oxygen saturation (StO2) have been recently shown to significantly correlate with the widely used method for noninvasively assessing vascular endothelial function, flow-mediated dilation (FMD). The purpose of this study was to examine the intraday and interday reliability of the reperfusi...

Background: Skeletal muscle satellite cells (SC) are instrumental in maintenance of muscle fibres, the adaptive responses to exercise, and there is an age-related decline in SC. A spatial relationship exists between SC and muscle fibre capillaries. In the present study, we aimed to investigate whether chronologic age has an impact on the spatial r...

Skeletal muscle satellite cells are considered to play a crucial role in muscle fiber maintenance, repair and remodeling. Our knowledge of the role of satellite cells in muscle fiber adaptation has traditionally relied on in vitro cell and in vivo animal models. Over the past decade, a genuine effort has been made to translate these results to huma...

New Findings What is the central question of this study? Can the near‐infrared spectroscopy (NIRS)‐derived reperfusion rate (slope 2) of tissue oxygen saturation ( S tO 2 ) be correlated with flow‐mediated dilation (FMD), the commonly used method to assess vascular endothelial function? What is the main finding and its importance? The present data...

Aim: A dysregulation of satellite cells may contribute to the progressive loss of muscle mass that occurs with age; however, older adults retain the ability to activate and expand their satellite cell pool in response to exercise. The modality of exercise capable of inducing the greatest acute response is unknown. We sought to characterize the acu...

The purpose of this study was to determine the effect of various non-hypertrophic exercise stimuli on satellite cell (SC) pool activity in human skeletal muscle. Previously untrained males and females (males: 29±9yr; females: 29±2yr, n=7 each) completed six weeks of very low volume high intensity sprint interval training (SIT-1). In a separate stud...

Introduction: The rate of adjustment (τ) of phase II pulmonary O₂ uptake (VO₂p) is slower when exercise transitions are initiated from an elevated baseline work rate (WR) and metabolic rate (MR). In this study, combinations of cycling cadence (40 vs. 90 rpm) and external WR were used to examine the effect of prior MR on τVO₂p. Methods: Eleven yo...

Purpose This study examined the impact of eccentric exercise-induced muscle damage on the rate of adjustment in muscle deoxygenation and pulmonary O2 uptake (\(\dot{V}{\text{O}}_{{2{\text{p}}}}\)) kinetics during moderate exercise. Methods Fourteen males (25 ± 3 year; mean ± SD) completed three step transitions to 90 % θL before (Pre), 24 h (Pos...