Pro-fibrogenic and adipogenic aspects of chronic muscle degeneration are contributed by distinct stromal cell subpopulations

Photobiomodulation therapy (PBMT) in skeletal muscle regeneration: A comprehensive review of mechanisms, clinical applications, and future directions

Photobiomodulation therapy (PBMT) emerged as a significant non-invasive method of stimulating regeneration of the skeletal muscle tissue. This review considers the pathophysiologic and molecular mechanisms of muscle repair, with a focus on the imperative of inflammation resolution, activation of satellite cells, mitochondrial ATP generation, and angiogenesis, with consideration of the role of PBMT. We systematically evaluate preclinical and clinical studies, highlighting the translational gaps caused by differences between controlled experimental models and the complex, heterogeneous nature of human muscle injuries. Variability in PBMT parameters-such as wavelength, fluence, and pulse mode-and the lack of standardized protocols are identified as major barriers to consistent therapeutic outcomes. Furthermore, we discuss the effects of PBMT in acute and chronic muscle injury models and provide an in-depth analysis of laser parameters to elucidate dose-response relationships. Future directions for research involve the application of real-time biofeedback devices, the utilization of artificial intelligence-based individualized therapeutic approaches, as well as the integration of photobiomodulation therapy with nanotechnology, biomaterials, and multiple mechanical stimulation methods. In concusion, while PBMT has significant potential for muscle regeneration therapies, its clinical application requires more complete mechanistic validation, rigorous standardization, and interdisciplinary technological development.

Detailed characterization of bone marrow adipose tissue mesenchymal stem cells in healthy donor, Fanconi anemia, and acute myeloid leukemia

Bone marrow is a complex tissue featuring distinct cellular organization and diverse cell types. Bone marrow adipose tissue (BMAT) is a dynamic component crucial for tissue function and disease processes. This study explores differences between bone marrow-derived mesenchymal stem cells (BM-MSCs) and BMAT-derived mesenchymal stem cells (BMAT-MSCs), isolated from the same cavity, examining their differentiation potential and secretory profiles. BM-MSCs and BMAT-MSCs both exhibit classical mesenchymal characteristics, with over 90 % positivity for markers such as CD105 and CD29. Notably, BMAT-MSCs display significantly higher differentiation potential than BM-MSCs, with enhanced osteogenic and adipogenic capabilities, as indicated by increased calcium accumulation and lipid storage. In Fanconi anemia (FA) and acute myeloid leukemia (AML), osteogenic potential is limited, indicating impaired differentiation under these pathological conditions. Gene expression analysis of adipogenic molecules and metabolic regulators revealed significant differences in expression profile between BM- and BMAT-MSCs, particularly during adipogenic differentiation, indicating distinct characteristics that were more notable in FAs and AMLs. Furthermore, metabolomic profiling of BM plasma, using GC-MS for in-vivo niche reflection, and lipid analysis via LC-qTOF-MS show significant lipidomic alterations in patient samples, highlighting metabolic dysregulation and lipid remodeling. Lipid-mediated signaling and membrane composition changes appear integral to disease mechanisms. In conclusion, this study highlights the distinctive molecular and metabolomic profiles and adaptive mechanisms of BM- and BMAT-MSCs in bone marrow pathologies.