Living High-Training Low on Mice Bone Parameters Analyzed through Complex Network Approach

Abstract

The aim of this study was to investigate the effect of 8 weeks of hypoxic exposition and physical training on healthy mice femur outcomes analyzed through conventional statistic and complex networks. The mice were divided into four groups, subjected to physical training (T; 40 min per day at 80% of critical velocity intensity) or not (N), exposed to hypoxic environment (“Living High-Training Low” model – LHTL; 18 h per day, FIO₂=19.5%; Hyp) or not (Nor). The complex network analysis performed interactions among parameters using values of critical “r” of 0.5 by Pearson correlations to edges construction, with Fruchterman-Reingold layout adopted for graph visualization. Pondered Degree, Betweenness, and Eigenvector metrics were chosen as centrality metrics. Two-way ANOVA, t-test and Pearson correlation were used with P<0.05. Femur phosphorus of T-Hyp was higher than all other groups (P<0.05) and correlated with bone density (r=0.65; P=0.042), bone mineral density (r=0.67; P=0.034) and% of mineral material (r=0.66, P=0.038). Overall, the complex network demonstrated improvements in bone volume, % of mineral material, bone density, and bone mineral density for T-Hyp over other groups. Association of physical training and hypoxia improved bone quality for healthy mice.

Keywords

hypoxic environment - bone mineral density - critical velocity - physical training - animal model - femur

Publication History

Received: 07 March 2024

Accepted: 01 July 2024

Article published online:
13 November 2024

• References

• 1 Hannah SS, McFadden S, McNeilly A. et al. “Take My Bone Away?” Hypoxia and bone: A narrative review. J Cell Physiol 2021; 236: 721-740
• 2 Usategui-Martín R, Rigual R, Ruiz-Mambrilla M. et al. Molecular Mechanisms Involved in Hypoxia-Induced Alterations in Bone Remodeling. Int J Mol Sci. 2022 23. 3233
• 3 Utting JC, Robins SP, Brandao-Burch A. et al. Hypoxia inhibits the growth, differentiation and bone-forming capacity of rat osteoblasts. Exp Cell Res 2006; 312: 1693-1702
• 4 Aido M, Kerschnitzki M, Hoerth R. et al. Effect of in vivo loading on bone composition varies with animal age. Exp Gerontol 2015; 63: 48-58
• 5 Schoenau E. From mechanostat theory to development of the "Functional Muscle-Bone-Unit". J Musculoskelet Neuronal Interact 2005; 5: 232-238
• 6 Willie BM, Zimmermann EA, Vitienes I. et al. Bone adaptation: Safety factors and load predictability in shaping skeletal form. Bone 2020; 131: 115114
• 7 Polisel EEC, Beck WR, Scariot PPM. et al. Effects of high-intensity interval training in more or less active mice on biomechanical, biophysical and biochemical bone parameters. Sci Rep 2021; 11: 6414
• 8 Levine BD, Stray-Gundersen J. "Living high-training low": effect of moderate-altitude acclimatization with low-altitude training on performance. J Appl Physiol 1985; 83: 102-112
• 9 Girard O, Brocherie F, Goods PSR. et al. An Updated Panorama of "Living Low-Training High" Altitude/Hypoxic Methods. Front Sports Act Living 2020; 2: 26
• 10 Bejder J, Nordsborg NB. Specificity of "Live High-Train Low" Altitude Training on Exercise Performance. Exerc Sport Sci Rev 2018; 46: 129-136
• 11 Brocherie F, Millet GP, Hauser A. et al. "Live High-Train Low and High" Hypoxic Training Improves Team-Sport Performance. Med Sci Sports Exerc 2015; 47: 2140-2149
• 12 Brugniaux JV, Schmitt L, Robach P. et al. Eighteen days of "living high, training low" stimulate erythropoiesis and enhance aerobic performance in elite middle-distance runners. J Appl Physiol 1985; 100: 203-211
• 13 Gore CJ, Hahn AG, Aughey RJ. et al. Live high:train low increases muscle buffer capacity and submaximal cycling efficiency. Acta Physiol Scand 2001; 173: 275-286
• 14 Inness MWH, Billaut F, Aughey RJ. Live-high train-low improves repeated time-trial and Yo-Yo IR2 performance in sub-elite team-sport athletes. J Sci Med Sport 2017; 20: 190-195
• 15 Roberts AD, Clark SA, Townsend NE. et al. Changes in performance, maximal oxygen uptake and maximal accumulated oxygen deficit after 5, 10 and 15 days of live high:train low altitude exposure. Eur J Appl Physiol 2003; 88: 390-395
• 16 Saugy JJ, Schmitt L, Hauser A. et al. Same Performance Changes after Live High-Train Low in Normobaric vs. Hypobaric Hypoxia. Front Physiol 2016; 7: 138
• 17 Siebenmann C, Robach P, Jacobs RA. et al. "Live high-train low" using normobaric hypoxia: a double-blinded, placebo-controlled study. J Appl Physiol 1985; 112: 106-117
• 18 Breda FL, Manchado-Gobatto FB, de Barros Sousa FA. et al. Complex networks analysis reinforces centrality hematological role on aerobic-anaerobic performances of the Brazilian Paralympic endurance team after altitude training. Sci Rep 2022; 12: 1148
• 19 Cirino C, Gobatto CA, Pinto AS. et al. Complex network model indicates a positive effect of inspiratory muscles pre-activation on performance parameters in a judo match. Sci Rep 2021; 11: 11148
• 20 Gobatto CA, Torres RS, Moura FA. et al. Corresponding Assessment Scenarios in Laboratory and on-Court Tests: Centrality Measurements by Complex Networks Analysis in Young Basketball Players. Sci Rep 2020; 10: 8620
• 21 Kraemer MB, Garbuio ALP, Kaneko LO. et al. Associations among sleep, hematologic profile, and aerobic and anerobic capacity of young swimmers: A complex network approach. Front Physiol 2022; 13: 948422
• 22 Manchado-Gobatto FB, Torres RS, Marostegan AB. et al. Complex Network Model Reveals the Impact of Inspiratory Muscle Pre-Activation on Interactions among Physiological Responses and Muscle Oxygenation during Running and Passive Recovery. Biology (Basel). 2022 11. 963
• 23 Kregel KC. Resource Book for the Design of Animal Exercise Protocols. Committee to Develop an American Physiological Society Resource Book for the Design of Animal Exercise Protocols. 2006
• 24 Institute for Laboratory Animal Research, National Research Council. Guide for the Care and Use of Laboratory Animals – Report in Brief. Washington, DC: National Academy Press; 2010
• 25 Scariot PPM, Papoti M, Polisel EEC. et al. Living high - training low model applied to C57BL/6J mice: Effects on physiological parameters related to aerobic fitness and acid-base balance. Life Sci 2023; 317: 121443
• 26 Parati G, Agostoni P, Basnyat B. et al. Clinical recommendations for high altitude exposure of individuals with pre-existing cardiovascular conditions: A joint statement by the European Society of Cardiology, the Council on Hypertension of the European Society of Cardiology, the European Society of Hypertension, the International Society of Mountain Medicine, the Italian Society of Hypertension and the Italian Society of Mountain Medicine. Eur Heart J 2018; 39: 1546-1554
• 27 Jepsen KJ, Silva MJ, Vashishth D. et al. Establishing biomechanical mechanisms in mouse models: practical guidelines for systematically evaluating phenotypic changes in the diaphyses of long bones. J Bone Miner Res 2015; 30: 951-966
• 28 Birocale AM, Medeiros AR, Ruffoni LD. et al. Bone mineral density is reduced by telmisartan in male spontaneously hypertensive rats. Pharmacol Rep 2016; 68: 1149-1153
• 29 Pacheco-Costa R, Campos JF, Katchburian E. et al. Modifications in bone matrix of estrogen-deficient rats treated with intermittent PTH. Biomed Res Int. 2015 454162.
• 30 Keenan MJ, Hegsted M, Jones KL. et al. Comparison of bone density measurement techniques: DXA and Archimedes' principle. J Bone Miner Res 1997; 12: 1903-1907
• 31 Fruchterman TMJ, Reingold EM. Graph drawing by force-directed placement. Software: Practice and Experience 1991; 21: 1129-1164
• 32 Freeman LC. Centrality in social networks: Conceptual clarification. Soc Networks 1978; 1: 238-263
• 33 Newman MEJ. Networks: An Introduction. Oxford University Press Inc.; New York: 2010
• 34 Freeman LC. A set of measures of centrality based on betweenness. J Sociometry. 1977 40. 35-41
• 35 Bonacich P. Factoring and weighting approaches to status scores and clique identification. J Math Sociol 1972; 2: 113-120
• 36 Oldham S, Fulcher B, Parkes L. et al. Consistency and differences between centrality measures across distinct classes of networks. PLoS One 2019; 14: e0220061
• 37 Harrison JS, Rameshwar P, Chang V. et al. Oxygen saturation in the bone marrow of healthy volunteers. Blood 2002; 99: 394
• 38 Bruick RK, McKnight SL. A conserved family of prolyl-4-hydroxylases that modify HIF. Science 2001; 294: 1337-1340
• 39 Epstein AC, Gleadle JM, McNeill LA. et al. C. elegans EGL-9 and mammalian homologs define a family of dioxygenases that regulate HIF by prolyl hydroxylation. Cell 2001; 107: 43-54
• 40 Knowles H. Hypoxia, hypoxia-inducible factor (HIF) and bone homeostasis: focus on osteoclast-mediated bone resorption. Trends. Cell Mol Biol 2015; 10: 91-104
• 41 Heaney RP. Phosphorus nutrition and the treatment of osteoporosis. Mayo Clin Proc 2004; 79: 91-97
• 42 Shao Y, Sun G, Cao S. et al. Bone phosphorus retention and bone development of broilers at different ages. Poult Sci 2019; 98: 2114-2121