The Effects of Exercise Serum From Prepubertal Girls and Women on In Vitro Myoblast and Osteoblast Proliferation and Differentiation

Purpose: In girls and women, the authors studied the effects of an acute bout of low-impact, moderate-intensity exercise serum on myoblast and osteoblast proliferation in vitro. Methods: A total of 12 pre/early pubertal girls (8–10 y old) and 12 women (20–30 y old) cycled at 60% VO2max for 1 hour followed by 1-hour recovery. Blood samples were collected at rest, mid-exercise, end of exercise, mid-recovery, and end of recovery. C2C12 myoblasts and MC3T3E1 osteoblasts were incubated with serum from each time point for 1 hour, then monitored for 24 hours (myoblasts) or 36 hours (osteoblasts) to examine proliferation. Cells were also monitored for 6 days (myoblasts) to examine myotube formation and 21 days (osteoblasts) to examine mineralization. Results: Exercise did not affect myoblast or osteoblast proliferation. Girls exhibited lower cell proliferation relative to women at end of exercise (osteoblasts, P = .041; myoblasts, P = .029) and mid-recovery (osteoblasts, P = .010). Mineralization was lower at end of recovery relative to rest (P = .014) in both girls and women. Myotube formation was not affected by exercise or group. Conclusion: The systemic environment following one acute bout of low-impact moderate-intensity exercise in girls and women does not elicit osteoblast or myoblast activity in vitro. Differences in myoblast and osteoblast proliferation between girls and women may be influenced by maturation.

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The Systemic Effects of Exercise on Regulators of Muscle and Bone in Girls and Women

Pediatric Exercise Science ◽

10.1123/pes.2019-0179 ◽

2020 ◽

Vol 32 (3) ◽

pp. 117-123

Author(s):

Yasmeen Mezil ◽

J. Obeid ◽

Sandeep Raha ◽

Thomas J. Hawke ◽

Brian W. Timmons

Keyword(s):

Growth Factor ◽

Fibroblast Growth Factor ◽

Fibroblast Growth Factor 2 ◽

Moderate Intensity ◽

Systemic Effects ◽

Fibroblast Growth ◽

Moderate Intensity Exercise ◽

Acute Bout ◽

Chemokine Ligand ◽

Prepubertal Girls

Purpose: To assess the systemic effects of an acute bout of moderate-intensity exercise on factors that are known to regulate muscle and bone growth in prepubertal girls and women. Methods: A total of 12 prepubertal girls (8–10 y) and 12 women (20–30 y) cycled at 60% maximal oxygen uptake for 1 hour followed by 1 hour recovery. Blood samples were collected at rest, mid-exercise, end of exercise, mid-recovery, and end of recovery. Plasma was analyzed for interleukin-6, chemokine ligand 1, fibroblast growth factor-2, total insulin growth factor-1 (IGF-1), and free IGF-1 using enzyme-linked immunosorbent assays assays. Results: Both groups had similar concentrations of systemic factors at baseline with the exception of free IGF-1, which was higher in girls (P = .001). Interleukin-6 response was lower in girls versus women (P = .04), with a difference of +105.1% at end of exercise (P < .001), +113.5% at mid-recovery (P = .001), and +93.2% at end of recovery (P = .02). Girls and women exhibited significant declines in chemokine ligand 1, fibroblast growth factor-2, and total IGF-1 during recovery. Conclusion: Compared with women, an acute bout of moderate-intensity exercise in girls elicits a lower inflammatory response, suggesting that other mechanisms may be more important for driving the anabolic effects of exercise on muscle and bone in girls.

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Phenol red mimics biological actions of estradiol: Enhancement of osteoblast proliferation in vitro and of type I collagen gene expression in bone and uterus of rats in vivo

Journal of Steroid Biochemistry ◽

10.1016/0022-4731(89)90239-2 ◽

1989 ◽

Vol 33 (5) ◽

pp. 907-914 ◽

Cited By ~ 31

Author(s):

Matthias Ernst ◽

Christoph Schmid ◽

E.Rudolf Froesch

Keyword(s):

Gene Expression ◽

Type I Collagen ◽

Type I ◽

Collagen Gene ◽

Phenol Red ◽

Osteoblast Proliferation ◽

Proliferation In Vitro ◽

Biological Actions

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Biomimetic Mineralization and Bioactivity of Phosphorylated Chitosan

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.288-289.429 ◽

2005 ◽

Vol 288-289 ◽

pp. 429-432 ◽

Cited By ~ 10

Author(s):

Zhi Qing Chen ◽

Quan Li Li ◽

Quan Zen ◽

Gang Li ◽

Hao Bin Jiang ◽

...

Keyword(s):

Calcium Phosphate ◽

Simulated Body Fluid ◽

Body Fluid ◽

Crystal Nucleation ◽

Osteoblast Proliferation ◽

Biomimetic Mineralization ◽

P Content ◽

Proliferation And Differentiation ◽

Nucleation Growth

Phosphorylated chitosans were synthesized as templates to manipulate hydroxyapatite (HA) crystal nucleation, growth and microstructure. Two kinds of insoluble phosphorylated chitosan were soaked in saturated Ca(OH)2 solution for 4 d and in 1.5× SBF (simulated body fluid) solutions for 14 d at 37 °C for biomimetic mineralization. A lower [P]-content of phosphorylated chitosan promoted greater mineralization than higher [P]-content. Phosphorylated chitosan inhibited osteoblast proliferation and differentiation in vitro, while calcium phosphate phosphorylated chitosan composites did not.

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Regulation of CPT I activity in intermyofibrillar and subsarcolemmal mitochondria from human and rat skeletal muscle

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.00237.2003 ◽

2004 ◽

Vol 286 (1) ◽

pp. E85-E91 ◽

Cited By ~ 32

Author(s):

Veronic Bezaire ◽

George J. F. Heigenhauser ◽

Lawrence L. Spriet

Keyword(s):

Skeletal Muscle ◽

Vastus Lateralis ◽

Moderate Intensity ◽

Rat Skeletal Muscle ◽

Moderate Intensity Exercise ◽

Mitochondrial Fractions ◽

Decreasing Ph ◽

Subsarcolemmal Mitochondria ◽

Cpt I

Carnitine palmitoyltransferase I (CPT I) is considered the rate-limiting enzyme in the transfer of long-chain fatty acids (LCFA) into the mitochondria and is reversibly inhibited by malonyl-CoA (M-CoA) in vitro. In rat skeletal muscle, M-CoA levels decrease during exercise, releasing the inhibition of CPT I and increasing LCFA oxidation. However, in human skeletal muscle, M-CoA levels do not change during moderate-intensity exercise despite large increases in fat oxidation, suggesting that M-CoA is not the sole regulator of increased CPT I activity during exercise. In the present study, we measured CPT I activity in intermyofibrillar (IMF) and subsarcolemmal (SS) mitochondria isolated from human vastus lateralis (VL), rat soleus (Sol), and red gastrocnemius (RG) muscles. We tested whether exercise-related levels (∼65% maximal O2 uptake) of calcium and adenylate charge metabolites (free AMP, ADP, and Pi) could override the M-CoA-induced inhibition of CPT I activity and explain the increased CPT I flux during exercise. Protein content was ∼25-40% higher in IMF than in SS mitochondria in all muscles. Maximal CPT I activity was similar in IMF and SS mitochondria in all muscles (VL: 282 ± 46 vs. 280 ± 51; Sol: 390 ± 81 vs. 368 ± 82; RG: 252 ± 71 vs. 278 ± 44 nmol·min-1·mg protein-1). Sensitivity to M-CoA did not differ between IMF and SS mitochondria in all muscles (25-31% inhibition in VL, 52-70% in Sol and RG). Calcium and adenylate charge metabolites did not override the M-CoA-induced inhibition of CPT I activity in mitochondria isolated from VL, Sol, and RG muscles. Decreasing pH from 7.1 to 6.8 reduced CPT I activity by ∼34-40% in both VL mitochondrial fractions. In summary, this study reports no differences in CPT I activity or sensitivity to M-CoA between IMF and SS mitochondria isolated from human and rat skeletal muscles. Exercise-induced increases in calcium and adenylate charge metabolites do not appear responsible for upregulating CPT I activity in human or rat skeletal muscle during moderate aerobic exercise.

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Mesoporous Bioactive Glass Promoted Osteoblast Proliferation and Differentiation In Vitro

Journal of Biomaterials and Tissue Engineering ◽

10.1166/jbt.2019.2007 ◽

2019 ◽

Vol 9 (4) ◽

pp. 462-467

Author(s):

Jianwei Chen ◽

Xiaosheng Yu ◽

Hao Ji ◽

Zhen Zong ◽

Wei Hong ◽

...

Keyword(s):

Bioactive Glass ◽

Osteoblast Proliferation ◽

Proliferation And Differentiation ◽

Mesoporous Bioactive Glass

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Effect of Titanium Nanoparticles on Osteoblast Proliferation

Nanoscience and Nanotechnology Letters ◽

10.1166/nnl.2020.3126 ◽

2020 ◽

Vol 12 (4) ◽

pp. 455-460

Author(s):

Yuan Wu ◽

Cuizhong Liu ◽

Ming Gao ◽

Qiang Liang ◽

Yu Jiang

Keyword(s):

Histochemical Staining ◽

Control Group ◽

Osteoblast Proliferation ◽

Osteogenic Activity ◽

Diphenyltetrazolium Bromide ◽

Proliferation And Differentiation ◽

Titanium Nanoparticles

This study aimed to observe the effect of titanium nanomaterials on osteoblastsin vitro. Osteoblasts were identified using histochemical staining, and they were examined using an MTT (3-(4,5Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay to determine the proliferation and differentiation of osteoblasts. In addition, we observed the effect of titanium nanomaterials on the function of osteoblasts. Compared with the control group, titanium nanomaterials promoted the growth, proliferation, and differentiation of osteoblasts. Our findings showed that titanium nanomaterials can significantly promote the proliferation of osteoblasts and enhance their osteogenic activity.

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