Increase of neuronal sprouting and migration using 780 nm laser phototherapy as procedure for cell therapy.
OBJECTIVE
The present study focuses on the effect of 780 nm laser irradiation on the growth of embryonic rat brain cultures embedded in NVR-Gel (cross-linked hyaluronic acid with adhesive molecule laminin and several growth factors). Dissociated neuronal cells were first grown in suspension attached to cylindrical microcarriers (MCs). The formed floating cell-MC aggregates were subsequently transferred into stationary cultures in gel and then laser treated. The response of neuronal growth following laser irradiation was investigated.


METHODS
Whole brains were dissected from 16 days Sprague-Dawley rat embryos. Cells were mechanically dissociated, using narrow pipettes, and seeded on positively charged cylindrical MCs. After 4-14 days in suspension, the formed floating cell-MC aggregates were seeded as stationary cultures in NVR-Gel. Single cell-MC aggregates were either irradiated with near-infrared 780 nm laser beam for 1, 4, or 7 minutes, or cultured without irradiation. Laser powers were 10, 30, 50, 110, 160, 200, and 250 mW.


RESULTS
780 nm laser irradiation accelerated fiber sprouting and neuronal cell migration from the aggregates. Furthermore, unlike control cultures, the irradiated cultures (mainly after 1 minute irradiation of 50 mW) were already established after a short time of cultivation. They contained a much higher number of large size neurons (P<0.01), which formed dense branched interconnected networks of thick neuronal fibers.


CONCLUSIONS
780 nm laser phototherapy of embryonic rat brain cultures embedded in hyaluronic acid-laminin gel and attached to positively charged cylindrical MCs, stimulated migration and fiber sprouting of neuronal cells aggregates, developed large size neurons with dense branched interconnected network of neuronal fibers and, therefore, can be considered as potential procedure for cell therapy of neuronal injury or disease.
Division of Peripheral Nerve Reconstruction, Tel Aviv Sourasky Medical Center, Tel Aviv University, Tel Aviv 64239, Israel. rochkind@zahav.net.il
Shimon
S
Rochkind
Dalia
D
El-Ani
Zvi
Z
Nevo
Abraham
A
Shahar
D000818:Animals; D001921:Brain / Q000166:cytology / Q000196:embryology; D002465:Cell Movement / Q000528:radiation effects*; D064987:Cell- and Tissue-Based Therapy / Q000379:methods*; D002478:Cells, Cultured; D028022:Low-Level Light Therapy; D009474:Neurons / Q000166:cytology / Q000502:physiology* / Q000528:radiation effects*; D010789:Phototherapy; D051381:Rats; D017207:Rats, Sprague-Dawley