Tomatidine Attenuates Inflammatory Responses to Exercise-Like Stimulation in Donor-derived Skeletal Muscle Myobundles
Main Article Content
Abstract
Donor-derived myotubes offer a pre-clinical model for studying muscle biology, the effects of exercise-like electrical stimulation, and assessing drug efficacy and toxicity. We engineered a 3D muscle microphysiological system from myoblasts isolated from vastus lateralis of young and older adults. Over a three-week differentiation process, we applied two cycles of low frequency electrical stimulation daily for seven days generating functional, mature myobundles, as confirmed by gene expression profiling. Both young- and old-derived myobundles showed synchronous contraction in response to electrical stimulation, however, the contraction magnitude was reduced in old-derived myobundles compared to young-derived myobundles. We then assessed the donor-specific response to tomatidine, a steroidal alkaloid found in the skin of green tomatoes, known to inhibit muscle atrophy and promote skeletal muscle hypertrophy. Bioinformatic analyses revealed that infusion of tomatidine during electrical stimulation modulated the IL-6/JAK/STAT3 pathway. The contraction magnitude decreased in the young-derived myobundles treated with tomatidine compared to vehicle-treated controls, while no significant difference was observed in the old-derived myobundles. Secretome analysis revealed age-related changes in secreted proteins linked to inflammation and extracellular matrix remodeling. Notably, tomatidine attenuates the inflammatory and extracellular matrix remodeling responses in the myobundles triggered by electrical stimulation, partially preventing the secretion of proinflammatory proteins. This intervention strategy helps balance muscle adaptation and repair, while limiting excessive proinflammatory responses. Our microphysiological system provides a valuable platform for investigating signaling pathways involved in muscle function, and pharmacological responses, advancing the understanding of age-related muscle biology.
Keywords:
donor-derived myobundles; muscle-on-a-chip; E-Stim-induced contraction; transcriptome; secretome; inflammation; tomatidine.
Article Details
How to Cite
PARAFATI, Maddalena et al.
Tomatidine Attenuates Inflammatory Responses to Exercise-Like Stimulation in Donor-derived Skeletal Muscle Myobundles.
Medical Research Archives, [S.l.], v. 13, n. 4, may 2025.
ISSN 2375-1924.
Available at: <https://esmed.org/MRA/mra/article/view/6423>. Date accessed: 23 june 2025.
doi: https://doi.org/10.18103/mra.v13i4.6423.
Section
Research Articles
The Medical Research Archives grants authors the right to publish and reproduce the unrevised contribution in whole or in part at any time and in any form for any scholarly non-commercial purpose with the condition that all publications of the contribution include a full citation to the journal as published by the Medical Research Archives.
References
1. Gronek, P. et al. A Review of Exercise as Medicine in Cardiovascular Disease: Pathology and Mechanism. Aging and disease 11, 327 (2020).
2. Izquierdo, M. et al. International Exercise Recommendations in Older Adults (ICFSR): Expert Consensus Guidelines. The Journal of nutrition, health and aging 25, 824–853 (2021).
3. Syeda, U. S. A., Battillo, D., Visaria, A. & Malin, S. K. The importance of exercise for glycemic control in type 2 diabetes. American Journal of Medicine Open 9, 100031 (2023).
4. Chomiuk, T., Niezgoda, N., Mamcarz, A. & Śliż, D. Physical activity in metabolic syndrome. Front. Physiol. 15, 1365761 (2024).
5. Lee, J. H. & Jun, H.-S. Role of Myokines in Regulating Skeletal Muscle Mass and Function. Front. Physiol. 10, 42 (2019).
6. Mathur, N. & Pedersen, B. K. Exercise as a Mean to Control Low‐Grade Systemic Inflammation. Mediators of Inflammation 2008, 109502 (2008).
7. Severinsen, M. C. K. & Pedersen, B. K. Muscle–Organ Crosstalk: The Emerging Roles of Myokines. Endocrine Reviews 41, 594–609 (2020).
8. Suzuki, K. Cytokine Response to Exercise and Its Modulation. Antioxidants 7, 17 (2018).
9. Oishi, Y. & Manabe, I. Macrophages in inflammation, repair and regeneration. International Immunology 30, 511–528 (2018).
10. Cerqueira, É., Marinho, D. A., Neiva, H. P. & Lourenço, O. Inflammatory Effects of High and Moderate Intensity Exercise—A Systematic Review. Front. Physiol. 10, 1550 (2020).
11. Jiao, A. et al. Regulation of skeletal myotube formation and alignment by nanotopographically controlled cell‐secreted extracellular matrix. J Biomedical Materials Res 106, 1543–1551 (2018).
12. Osses, N., Casar, J. C. & Brandan, E. Inhibition of extracellular matrix assembly induces the expression of osteogenic markers in skeletal muscle cells by a BMP-2 independent mechanism. BMC Cell Biol 10, 73 (2009).
13. Melo, F., Carey, D. J. & Brandan, E. Extracellular matrix is required for skeletal muscle differentiation but not myogenin expression. J. Cell. Biochem. 62, 227–239 (1996).
14. Mu, X., Urso, M. L., Murray, K., Fu, F. & Li, Y. Relaxin Regulates MMP Expression and Promotes Satellite Cell Mobilization During Muscle Healing in Both Young and Aged Mice. The American Journal of Pathology 177, 2399–2410 (2010).
15. Alameddine, H. S. Matrix metalloproteinases in skeletal muscles: Friends or foes? Neurobiology of Disease 48, 508–518 (2012).
16. Carmeli, E., Moas, M., Lennon, S. & Powers, S. K. High intensity exercise increases expression of matrix metalloproteinases in fast skeletal muscle fibres. Experimental Physiology 90, 613–619 (2005).
17. Mackey, A. L., Donnelly, A. E., Turpeenniemi-Hujanen, T. & Roper, H. P. Skeletal muscle collagen content in humans after high-force eccentric contractions. Journal of Applied Physiology 97, 197–203 (2004).
18. Heinemeier, K. M. et al. Expression of collagen and related growth factors in rat tendon and skeletal muscle in response to specific contraction types. The Journal of Physiology 582, 1303–1316 (2007).
19. Tuttle, C. S. L., Thang, L. A. N. & Maier, A. B. Markers of inflammation and their association with muscle strength and mass: A systematic review and meta-analysis. Ageing Research Reviews 64, 101185 (2020).
20. Bettariga, F. et al. Exercise training mode effects on myokine expression in healthy adults: A systematic review with meta-analysis. Journal of Sport and Health Science 13, 764–779 (2024).
21. Pedersen, B. K., Åkerström, T. C. A., Nielsen, A. R. & Fischer, C. P. Role of myokines in exercise and metabolism. Journal of Applied Physiology 103, 1093–1098 (2007).
22. Lesnak, J. B., Berardi, G. & Sluka, K. A. Influence of routine exercise on the peripheral immune system to prevent and alleviate pain. Neurobiology of Pain 13, 100126 (2023).
23. Khodabukus, A. et al. Electrical stimulation increases hypertrophy and metabolic flux in tissue-engineered human skeletal muscle. Biomaterials 198, 259–269 (2019).
24. Kim, J.-H., Yu, S.-M. & Son, J. W. Human Tissue-Engineered Skeletal Muscle: A Tool for Metabolic Research. Endocrinol Metab 37, 408–414 (2022).
25. Dennis, R. G. & Kosnik, Ii, P. E. EXCITABILITY AND ISOMETRIC CONTRACTILE PROPERTIES OF MAMMALIAN SKELETAL MUSCLE CONSTRUCTS ENGINEERED IN VITRO. In Vitro Cell Dev Biol Anim 36, 327 (2000).
26. Ebrahimi, M. et al. De novo revertant fiber formation and therapy testing in a 3D culture model of Duchenne muscular dystrophy skeletal muscle. Acta Biomaterialia 132, 227–244 (2021).
27. Dessauge, F., Schleder, C., Perruchot, M.-H. & Rouger, K. 3D in vitro models of skeletal muscle: myopshere, myobundle and bioprinted muscle construct. Vet Res 52, 72 (2021).
28. Carraro, E., Rossi, L., Maghin, E., Canton, M. & Piccoli, M. 3D in vitro Models of Pathological Skeletal Muscle: Which Cells and Scaffolds to Elect? Front. Bioeng. Biotechnol. 10, 941623 (2022).
29. Mankhong, S. et al. Experimental Models of Sarcopenia: Bridging Molecular Mechanism and Therapeutic Strategy. Cells 9, 1385 (2020).
30. Giza, S. et al. Microphysiological system for studying contractile differences in young, active, and old, sedentary adult derived skeletal muscle cells. Aging Cell 21, e13650 (2022).
31. Parafati, M., Thwin, Z., Malany, L. K., Coen, P. M. & Malany, S. Microgravity Accelerates Skeletal Muscle Degeneration: Functional and Transcriptomic Insights from a Muscle Lab-on-Chip Model Onboard the ISS. Preprint at https://doi.org/10.1101/2025.01.26.634580 (2025).
32. Pedrotty, D. M. et al. Engineering skeletal myoblasts: roles of three-dimensional culture and electrical stimulation. American Journal of Physiology-Heart and Circulatory Physiology 288, H1620–H1626 (2005).
33. Huang, Y.-C., Dennis, R. G. & Baar, K. Cultured slow vs. fast skeletal muscle cells differ in physiology and responsiveness to stimulation. American Journal of Physiology-Cell Physiology 291, C11–C17 (2006).
34. Flaibani, M. et al. Muscle Differentiation and Myotubes Alignment Is Influenced by Micropatterned Surfaces and Exogenous Electrical Stimulation. Tissue Engineering Part A 15, 2447–2457 (2009).
35. Hurley, B. F., Hanson, E. D. & Sheaff, A. K. Strength Training as a Countermeasure to Aging Muscle and Chronic Disease: Sports Medicine 41, 289–306 (2011).
36. Cruz-Jentoft, A. J. et al. Sarcopenia: revised European consensus on definition and diagnosis. Age and Ageing 48, 16–31 (2019).
37. Dyle, M. C. et al. Systems-based Discovery of Tomatidine as a Natural Small Molecule Inhibitor of Skeletal Muscle Atrophy. Journal of Biological Chemistry 289, 14913–14924 (2014).
38. Ebert, S. M. et al. Identification and Small Molecule Inhibition of an Activating Transcription Factor 4 (ATF4)-dependent Pathway to Age-related Skeletal Muscle Weakness and Atrophy. Journal of Biological Chemistry 290, 25497–25511 (2015).
39. Chiu, F.-L. & Lin, J.-K. Tomatidine inhibits iNOS and COX‐2 through suppression of NF‐κB and JNK pathways in LPS‐stimulated mouse macrophages. FEBS Letters 582, 2407–2412 (2008).
40. Kuo, C.-Y. et al. Tomatidine Attenuates Airway Hyperresponsiveness and Inflammation by Suppressing Th2 Cytokines in a Mouse Model of Asthma. Mediators of Inflammation 2017, 1–9 (2017).
41. Zhao, B., Zhou, B., Bao, L., Yang, Y. & Guo, K. Alpha-Tomatine Exhibits Anti-inflammatory Activity in Lipopolysaccharide-Activated Macrophages. Inflammation 38, 1769–1776 (2015).
42. Parafati, M. et al. Human skeletal muscle tissue chip autonomous payload reveals changes in fiber type and metabolic gene expression due to spaceflight. npj Microgravity 9, 77 (2023).
43. Liberzon, A. et al. The Molecular Signatures Database Hallmark Gene Set Collection. Cell Systems 1, 417–425 (2015).
44. Moresi, V., Adamo, S. & Berghella, L. The JAK/ STAT Pathway in Skeletal Muscle Pathophysiology. Front. Physiol. 10, 500 (2019).
45. Hindi, L., McMillan, J., Afroze, D., Hindi, S. & Kumar, A. Isolation, Culturing, and Differentiation of Primary Myoblasts from Skeletal Muscle of Adult Mice. BIO-PROTOCOL 7, (2017).
46. Yamawaki, Y., Kimura, H., Hosoi, T. & Ozawa, K. MyD88 plays a key role in LPS-induced Stat3 activation in the hypothalamus. American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 298, R403–R410 (2010).
47. Peake, J. M., Neubauer, O., Della Gatta, P. A. & Nosaka, K. Muscle damage and inflammation during recovery from exercise. Journal of Applied Physiology 122, 559–570 (2017).
48. Dessauge, F., Schleder, C., Perruchot, M.-H. & Rouger, K. 3D in vitro models of skeletal muscle: myopshere, myobundle and bioprinted muscle construct. Vet Res 52, 72 (2021).
49. Nikolić, N. et al. Electrical Pulse Stimulation of Cultured Human Skeletal Muscle Cells as an In Vitro Model of Exercise. PLoS ONE 7, e33203 (2012).
50. Saito, Y., Chikenji, T. S., Matsumura, T., Nakano, M. & Fujimiya, M. Exercise enhances skeletal muscle regeneration by promoting senescence in fibro-adipogenic progenitors. Nat Commun 11, 889 (2020).
51. Khan, K. M. & Scott, A. Mechanotherapy: how physical therapists’ prescription of exercise promotes tissue repair. Br J Sports Med 43, 247–252 (2009).
52. Gleeson, M. et al. The anti-inflammatory effects of exercise: mechanisms and implications for the prevention and treatment of disease. Nat Rev Immunol 11, 607–615 (2011).
53. Roubenoff, R. Physical Activity, Inflammation, and Muscle Loss. Nutrition Reviews 65, S208–S212 (2008).
54. Scheffer, D. D. L. & Latini, A. Exercise-induced immune system response: Anti-inflammatory status on peripheral and central organs. Biochimica et Biophysica Acta (BBA) - Molecular Basis of Disease 1866, 165823 (2020).
55. Latroche, C. et al. Coupling between Myogenesis and Angiogenesis during Skeletal Muscle Regeneration Is Stimulated by Restorative Macrophages. Stem Cell Reports 9, 2018–2033 (2017).
56. Ross, M., Kargl, C. K., Ferguson, R., Gavin, T. P. & Hellsten, Y. Exercise-induced skeletal muscle angiogenesis: impact of age, sex, angiocrines and cellular mediators. Eur J Appl Physiol 123, 1415–1432 (2023).
57. Schnyder, S. & Handschin, C. Skeletal muscle as an endocrine organ: PGC-1α, myokines and exercise. Bone 80, 115–125 (2015).
58. Catoire, M., Mensink, M., Kalkhoven, E., Schrauwen, P. & Kersten, S. Identification of human exercise-induced myokines using secretome analysis. Physiological Genomics 46, 256–267 (2014).
59. Hjorth, M. et al. The effect of acute and long-term physical activity on extracellular matrix and serglycin in human skeletal muscle. Physiol Rep 3, e12473 (2015).
60. Tidball, J. G. Regulation of muscle growth and regeneration by the immune system. Nat Rev Immunol 17, 165–178 (2017).
61. Langston, P. K. & Mathis, D. Immunological regulation of skeletal muscle adaptation to exercise. Cell Metabolism 36, 1175–1183 (2024).
62. Pérez-Baos, S. et al. Mediators and Patterns of Muscle Loss in Chronic Systemic Inflammation. Front. Physiol. 9, 409 (2018).
63. Silva, K. A. S. et al. Inhibition of Stat3 Activation Suppresses Caspase-3 and the Ubiquitin-Proteasome System, Leading to Preservation of Muscle Mass in Cancer Cachexia. Journal of Biological Chemistry 290, 11177–11187 (2015).
64. Huang, Z. et al. Inhibition of IL-6/JAK/STAT3 pathway rescues denervation-induced skeletal muscle atrophy. Ann Transl Med 8, 1681–1681 (2020).
65. Xu, M. et al. JAK inhibition alleviates the cellular senescence-associated secretory phenotype and frailty in old age. Proc. Natl. Acad. Sci. U.S.A. 112, (2015).
66. Chen, Z., Li, B., Zhan, R.-Z., Rao, L. & Bursac, N. Exercise mimetics and JAK inhibition attenuate IFN-γ–induced wasting in engineered human skeletal muscle. Sci. Adv. 7, eabd9502 (2021).
67. Zimmers, T. A., Fishel, M. L. & Bonetto, A. STAT3 in the systemic inflammation of cancer cachexia. Seminars in Cell & Developmental Biology 54, 28–41 (2016).
68. Chen, X. & Li, Y. Role of matrix metalloproteinases in skeletal muscle: Migration, differentiation, regeneration and fibrosis. Cell Adhesion & Migration 3, 337–341 (2009).
69. Sprenger, H. et al. Enhanced release of cytokines, interleukin-2 receptors, and neopterin after long-distance running. Clinical Immunology and Immunopathology 63, 188–195 (1992).
70. Drenth, J. P. et al. Endurance run increases circulating IL-6 and IL-1ra but downregulates ex vivo TNF-alpha and IL-1 beta production. Journal of Applied Physiology 79, 1497–1503 (1995).
71. Nehlsen-Cannarella, S. L. et al. Carbohydrate and the cytokine response to 2.5 h of running. Journal of Applied Physiology 82, 1662–1667 (1997).
72. Begue, G. et al. Early Activation of Rat Skeletal Muscle IL-6/STAT1/STAT3 Dependent Gene Expression in Resistance Exercise Linked to Hypertrophy. PLoS ONE 8, e57141 (2013).
73. Trenerry, M. K., Carey, K. A., Ward, A. C. & Cameron-Smith, D. STAT3 signaling is activated in human skeletal muscle following acute resistance exercise. Journal of Applied Physiology 102, 1483–1489 (2007).
2. Izquierdo, M. et al. International Exercise Recommendations in Older Adults (ICFSR): Expert Consensus Guidelines. The Journal of nutrition, health and aging 25, 824–853 (2021).
3. Syeda, U. S. A., Battillo, D., Visaria, A. & Malin, S. K. The importance of exercise for glycemic control in type 2 diabetes. American Journal of Medicine Open 9, 100031 (2023).
4. Chomiuk, T., Niezgoda, N., Mamcarz, A. & Śliż, D. Physical activity in metabolic syndrome. Front. Physiol. 15, 1365761 (2024).
5. Lee, J. H. & Jun, H.-S. Role of Myokines in Regulating Skeletal Muscle Mass and Function. Front. Physiol. 10, 42 (2019).
6. Mathur, N. & Pedersen, B. K. Exercise as a Mean to Control Low‐Grade Systemic Inflammation. Mediators of Inflammation 2008, 109502 (2008).
7. Severinsen, M. C. K. & Pedersen, B. K. Muscle–Organ Crosstalk: The Emerging Roles of Myokines. Endocrine Reviews 41, 594–609 (2020).
8. Suzuki, K. Cytokine Response to Exercise and Its Modulation. Antioxidants 7, 17 (2018).
9. Oishi, Y. & Manabe, I. Macrophages in inflammation, repair and regeneration. International Immunology 30, 511–528 (2018).
10. Cerqueira, É., Marinho, D. A., Neiva, H. P. & Lourenço, O. Inflammatory Effects of High and Moderate Intensity Exercise—A Systematic Review. Front. Physiol. 10, 1550 (2020).
11. Jiao, A. et al. Regulation of skeletal myotube formation and alignment by nanotopographically controlled cell‐secreted extracellular matrix. J Biomedical Materials Res 106, 1543–1551 (2018).
12. Osses, N., Casar, J. C. & Brandan, E. Inhibition of extracellular matrix assembly induces the expression of osteogenic markers in skeletal muscle cells by a BMP-2 independent mechanism. BMC Cell Biol 10, 73 (2009).
13. Melo, F., Carey, D. J. & Brandan, E. Extracellular matrix is required for skeletal muscle differentiation but not myogenin expression. J. Cell. Biochem. 62, 227–239 (1996).
14. Mu, X., Urso, M. L., Murray, K., Fu, F. & Li, Y. Relaxin Regulates MMP Expression and Promotes Satellite Cell Mobilization During Muscle Healing in Both Young and Aged Mice. The American Journal of Pathology 177, 2399–2410 (2010).
15. Alameddine, H. S. Matrix metalloproteinases in skeletal muscles: Friends or foes? Neurobiology of Disease 48, 508–518 (2012).
16. Carmeli, E., Moas, M., Lennon, S. & Powers, S. K. High intensity exercise increases expression of matrix metalloproteinases in fast skeletal muscle fibres. Experimental Physiology 90, 613–619 (2005).
17. Mackey, A. L., Donnelly, A. E., Turpeenniemi-Hujanen, T. & Roper, H. P. Skeletal muscle collagen content in humans after high-force eccentric contractions. Journal of Applied Physiology 97, 197–203 (2004).
18. Heinemeier, K. M. et al. Expression of collagen and related growth factors in rat tendon and skeletal muscle in response to specific contraction types. The Journal of Physiology 582, 1303–1316 (2007).
19. Tuttle, C. S. L., Thang, L. A. N. & Maier, A. B. Markers of inflammation and their association with muscle strength and mass: A systematic review and meta-analysis. Ageing Research Reviews 64, 101185 (2020).
20. Bettariga, F. et al. Exercise training mode effects on myokine expression in healthy adults: A systematic review with meta-analysis. Journal of Sport and Health Science 13, 764–779 (2024).
21. Pedersen, B. K., Åkerström, T. C. A., Nielsen, A. R. & Fischer, C. P. Role of myokines in exercise and metabolism. Journal of Applied Physiology 103, 1093–1098 (2007).
22. Lesnak, J. B., Berardi, G. & Sluka, K. A. Influence of routine exercise on the peripheral immune system to prevent and alleviate pain. Neurobiology of Pain 13, 100126 (2023).
23. Khodabukus, A. et al. Electrical stimulation increases hypertrophy and metabolic flux in tissue-engineered human skeletal muscle. Biomaterials 198, 259–269 (2019).
24. Kim, J.-H., Yu, S.-M. & Son, J. W. Human Tissue-Engineered Skeletal Muscle: A Tool for Metabolic Research. Endocrinol Metab 37, 408–414 (2022).
25. Dennis, R. G. & Kosnik, Ii, P. E. EXCITABILITY AND ISOMETRIC CONTRACTILE PROPERTIES OF MAMMALIAN SKELETAL MUSCLE CONSTRUCTS ENGINEERED IN VITRO. In Vitro Cell Dev Biol Anim 36, 327 (2000).
26. Ebrahimi, M. et al. De novo revertant fiber formation and therapy testing in a 3D culture model of Duchenne muscular dystrophy skeletal muscle. Acta Biomaterialia 132, 227–244 (2021).
27. Dessauge, F., Schleder, C., Perruchot, M.-H. & Rouger, K. 3D in vitro models of skeletal muscle: myopshere, myobundle and bioprinted muscle construct. Vet Res 52, 72 (2021).
28. Carraro, E., Rossi, L., Maghin, E., Canton, M. & Piccoli, M. 3D in vitro Models of Pathological Skeletal Muscle: Which Cells and Scaffolds to Elect? Front. Bioeng. Biotechnol. 10, 941623 (2022).
29. Mankhong, S. et al. Experimental Models of Sarcopenia: Bridging Molecular Mechanism and Therapeutic Strategy. Cells 9, 1385 (2020).
30. Giza, S. et al. Microphysiological system for studying contractile differences in young, active, and old, sedentary adult derived skeletal muscle cells. Aging Cell 21, e13650 (2022).
31. Parafati, M., Thwin, Z., Malany, L. K., Coen, P. M. & Malany, S. Microgravity Accelerates Skeletal Muscle Degeneration: Functional and Transcriptomic Insights from a Muscle Lab-on-Chip Model Onboard the ISS. Preprint at https://doi.org/10.1101/2025.01.26.634580 (2025).
32. Pedrotty, D. M. et al. Engineering skeletal myoblasts: roles of three-dimensional culture and electrical stimulation. American Journal of Physiology-Heart and Circulatory Physiology 288, H1620–H1626 (2005).
33. Huang, Y.-C., Dennis, R. G. & Baar, K. Cultured slow vs. fast skeletal muscle cells differ in physiology and responsiveness to stimulation. American Journal of Physiology-Cell Physiology 291, C11–C17 (2006).
34. Flaibani, M. et al. Muscle Differentiation and Myotubes Alignment Is Influenced by Micropatterned Surfaces and Exogenous Electrical Stimulation. Tissue Engineering Part A 15, 2447–2457 (2009).
35. Hurley, B. F., Hanson, E. D. & Sheaff, A. K. Strength Training as a Countermeasure to Aging Muscle and Chronic Disease: Sports Medicine 41, 289–306 (2011).
36. Cruz-Jentoft, A. J. et al. Sarcopenia: revised European consensus on definition and diagnosis. Age and Ageing 48, 16–31 (2019).
37. Dyle, M. C. et al. Systems-based Discovery of Tomatidine as a Natural Small Molecule Inhibitor of Skeletal Muscle Atrophy. Journal of Biological Chemistry 289, 14913–14924 (2014).
38. Ebert, S. M. et al. Identification and Small Molecule Inhibition of an Activating Transcription Factor 4 (ATF4)-dependent Pathway to Age-related Skeletal Muscle Weakness and Atrophy. Journal of Biological Chemistry 290, 25497–25511 (2015).
39. Chiu, F.-L. & Lin, J.-K. Tomatidine inhibits iNOS and COX‐2 through suppression of NF‐κB and JNK pathways in LPS‐stimulated mouse macrophages. FEBS Letters 582, 2407–2412 (2008).
40. Kuo, C.-Y. et al. Tomatidine Attenuates Airway Hyperresponsiveness and Inflammation by Suppressing Th2 Cytokines in a Mouse Model of Asthma. Mediators of Inflammation 2017, 1–9 (2017).
41. Zhao, B., Zhou, B., Bao, L., Yang, Y. & Guo, K. Alpha-Tomatine Exhibits Anti-inflammatory Activity in Lipopolysaccharide-Activated Macrophages. Inflammation 38, 1769–1776 (2015).
42. Parafati, M. et al. Human skeletal muscle tissue chip autonomous payload reveals changes in fiber type and metabolic gene expression due to spaceflight. npj Microgravity 9, 77 (2023).
43. Liberzon, A. et al. The Molecular Signatures Database Hallmark Gene Set Collection. Cell Systems 1, 417–425 (2015).
44. Moresi, V., Adamo, S. & Berghella, L. The JAK/ STAT Pathway in Skeletal Muscle Pathophysiology. Front. Physiol. 10, 500 (2019).
45. Hindi, L., McMillan, J., Afroze, D., Hindi, S. & Kumar, A. Isolation, Culturing, and Differentiation of Primary Myoblasts from Skeletal Muscle of Adult Mice. BIO-PROTOCOL 7, (2017).
46. Yamawaki, Y., Kimura, H., Hosoi, T. & Ozawa, K. MyD88 plays a key role in LPS-induced Stat3 activation in the hypothalamus. American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 298, R403–R410 (2010).
47. Peake, J. M., Neubauer, O., Della Gatta, P. A. & Nosaka, K. Muscle damage and inflammation during recovery from exercise. Journal of Applied Physiology 122, 559–570 (2017).
48. Dessauge, F., Schleder, C., Perruchot, M.-H. & Rouger, K. 3D in vitro models of skeletal muscle: myopshere, myobundle and bioprinted muscle construct. Vet Res 52, 72 (2021).
49. Nikolić, N. et al. Electrical Pulse Stimulation of Cultured Human Skeletal Muscle Cells as an In Vitro Model of Exercise. PLoS ONE 7, e33203 (2012).
50. Saito, Y., Chikenji, T. S., Matsumura, T., Nakano, M. & Fujimiya, M. Exercise enhances skeletal muscle regeneration by promoting senescence in fibro-adipogenic progenitors. Nat Commun 11, 889 (2020).
51. Khan, K. M. & Scott, A. Mechanotherapy: how physical therapists’ prescription of exercise promotes tissue repair. Br J Sports Med 43, 247–252 (2009).
52. Gleeson, M. et al. The anti-inflammatory effects of exercise: mechanisms and implications for the prevention and treatment of disease. Nat Rev Immunol 11, 607–615 (2011).
53. Roubenoff, R. Physical Activity, Inflammation, and Muscle Loss. Nutrition Reviews 65, S208–S212 (2008).
54. Scheffer, D. D. L. & Latini, A. Exercise-induced immune system response: Anti-inflammatory status on peripheral and central organs. Biochimica et Biophysica Acta (BBA) - Molecular Basis of Disease 1866, 165823 (2020).
55. Latroche, C. et al. Coupling between Myogenesis and Angiogenesis during Skeletal Muscle Regeneration Is Stimulated by Restorative Macrophages. Stem Cell Reports 9, 2018–2033 (2017).
56. Ross, M., Kargl, C. K., Ferguson, R., Gavin, T. P. & Hellsten, Y. Exercise-induced skeletal muscle angiogenesis: impact of age, sex, angiocrines and cellular mediators. Eur J Appl Physiol 123, 1415–1432 (2023).
57. Schnyder, S. & Handschin, C. Skeletal muscle as an endocrine organ: PGC-1α, myokines and exercise. Bone 80, 115–125 (2015).
58. Catoire, M., Mensink, M., Kalkhoven, E., Schrauwen, P. & Kersten, S. Identification of human exercise-induced myokines using secretome analysis. Physiological Genomics 46, 256–267 (2014).
59. Hjorth, M. et al. The effect of acute and long-term physical activity on extracellular matrix and serglycin in human skeletal muscle. Physiol Rep 3, e12473 (2015).
60. Tidball, J. G. Regulation of muscle growth and regeneration by the immune system. Nat Rev Immunol 17, 165–178 (2017).
61. Langston, P. K. & Mathis, D. Immunological regulation of skeletal muscle adaptation to exercise. Cell Metabolism 36, 1175–1183 (2024).
62. Pérez-Baos, S. et al. Mediators and Patterns of Muscle Loss in Chronic Systemic Inflammation. Front. Physiol. 9, 409 (2018).
63. Silva, K. A. S. et al. Inhibition of Stat3 Activation Suppresses Caspase-3 and the Ubiquitin-Proteasome System, Leading to Preservation of Muscle Mass in Cancer Cachexia. Journal of Biological Chemistry 290, 11177–11187 (2015).
64. Huang, Z. et al. Inhibition of IL-6/JAK/STAT3 pathway rescues denervation-induced skeletal muscle atrophy. Ann Transl Med 8, 1681–1681 (2020).
65. Xu, M. et al. JAK inhibition alleviates the cellular senescence-associated secretory phenotype and frailty in old age. Proc. Natl. Acad. Sci. U.S.A. 112, (2015).
66. Chen, Z., Li, B., Zhan, R.-Z., Rao, L. & Bursac, N. Exercise mimetics and JAK inhibition attenuate IFN-γ–induced wasting in engineered human skeletal muscle. Sci. Adv. 7, eabd9502 (2021).
67. Zimmers, T. A., Fishel, M. L. & Bonetto, A. STAT3 in the systemic inflammation of cancer cachexia. Seminars in Cell & Developmental Biology 54, 28–41 (2016).
68. Chen, X. & Li, Y. Role of matrix metalloproteinases in skeletal muscle: Migration, differentiation, regeneration and fibrosis. Cell Adhesion & Migration 3, 337–341 (2009).
69. Sprenger, H. et al. Enhanced release of cytokines, interleukin-2 receptors, and neopterin after long-distance running. Clinical Immunology and Immunopathology 63, 188–195 (1992).
70. Drenth, J. P. et al. Endurance run increases circulating IL-6 and IL-1ra but downregulates ex vivo TNF-alpha and IL-1 beta production. Journal of Applied Physiology 79, 1497–1503 (1995).
71. Nehlsen-Cannarella, S. L. et al. Carbohydrate and the cytokine response to 2.5 h of running. Journal of Applied Physiology 82, 1662–1667 (1997).
72. Begue, G. et al. Early Activation of Rat Skeletal Muscle IL-6/STAT1/STAT3 Dependent Gene Expression in Resistance Exercise Linked to Hypertrophy. PLoS ONE 8, e57141 (2013).
73. Trenerry, M. K., Carey, K. A., Ward, A. C. & Cameron-Smith, D. STAT3 signaling is activated in human skeletal muscle following acute resistance exercise. Journal of Applied Physiology 102, 1483–1489 (2007).