Modulation of hippocampal neurogenesis by Nano-Pulsed Laser Therapy

Neurogenesis is a physiological process through which new neurons are generated and it occurs throughout life, subverting the old dogma stating to the inability of the adult brain to replace neurons. Specifically, neurogenesis take place thanks to the presence of neuronal stem cells (NSCs) located in the subventricular zone of the lateral ventricle and in the subgranular zone of the dentate gyrus of the hippocampus. Data present in the literature demonstrate that neurogenesis in the hippocampus decreases during aging and it is impaired in neurodegenerative diseases, such as Alzheimer’s disease, and after traumatic brain injury (TBI). Traumatic Brain Injury (TBI) is a chronic disease that occurs after a head trauma and the results of which are permanent. One of the main area affected by TBI is the hippocampus a brain region that plays a pivotal role in learning and memory. For this reason there is an increased interest in TBI research, particularly as it relates to finding a possible cure, which currently does not exist. The goal of the research I conducted was to stimulate NSCs to proliferate and differentiate so as to restore the neurogenesis process in the brain. Specifically, I tested the effect of a highly innovative non-invasive device that combines the benefits of both near infrared laser light (808nm) and ultrasound waves, optoacoustically generated with each short (10ns) high-energy (15mJ) laser pulse within the tissue. Dr. Micci’s laboratory demonstrated the beneficial effect of NPLT in a rat model of brain trauma. However, the mechanism by which NPLT stimulates NSCs is not well understood. At the completion of this project I will have gained valuable knowledge of the effects of NPLT on neurogenesis and provided a unique therapeutic strategy based on a self-repair via stimulation of NSCs that are already present in the brain.