Low-level laser therapy to the bone marrow: A new therapeutic approach to neurodegenerative diseases

In this communication, low-level laser therapy (LLLT) ability to stimulate mesenchymal stem cells (MSCs) in autologous bone marrow (BM) and enhance MSCs capacity to infiltrate the brain, clear β-amyloid, and improve cognition is reviewed. We recently reported that LLLT applied to the BM enhanced proliferation of MSCs and their mobilization toward ischemic heart region, suggests possible application of this approach in regenerative medicine and neurodegenerative diseases. Furthermore, it was shown that circulating monocytes can infiltrate to the brain and reduce brain amyloid load in an Alzheimer’s disease (AD) mouse model. MSCs from wild type mice stimulated with LLLT were shown to increase their ability to maturate toward a monocyte lineage, and to increase phagocytosis of soluble Aβ in vitro. Furthermore, weekly LLLT for 2 months to the BM, starting at 4 months of age (progressive stage of the disease in this 5X FAD transgenic male mice), improved memory and spatial learning, as compared to sham treated AD mice. Histology revealed a significant reduction in Aβ brain burden in laser treated mice as compared to nonlaser treated ones. The use of LLLT to the BM is suggested as a therapeutic application in progressive stages of AD, and implies its role in mediating MSC therapy in brain amyloidogenic disease.