title: Transcranial low-level laser therapy improves neurological performance in traumatic brain injury in mice: effect of treatment repetition regimen.
abstract: Low-level laser (light) therapy (LLLT) has been clinically applied around the world for a spectrum of disorders requiring healing, regeneration and prevention of tissue death. One area that is attracting growing interest in this scope is the use of transcranial LLLT to treat stroke and traumatic brain injury (TBI). We developed a mouse model of severe TBI induced by controlled cortical impact and explored the effect of different treatment schedules. Adult male BALB/c mice were divided into 3 broad groups (a) sham-TBI sham-treatment, (b) real-TBI sham-treatment, and (c) real-TBI active-treatment. Mice received active-treatment (transcranial LLLT by continuous wave 810 nm laser, 25 mW/cm(2), 18 J/cm(2), spot diameter 1 cm) while sham-treatment was immobilization only, delivered either as a single treatment at 4 hours post TBI, as 3 daily treatments commencing at 4 hours post TBI or as 14 daily treatments. Mice were sacrificed at 0, 4, 7, 14 and 28 days post-TBI for histology or histomorphometry, and injected with bromodeoxyuridine (BrdU) at days 21-27 to allow identification of proliferating cells. Mice with severe TBI treated with 1-laser Tx (and to a greater extent 3-laser Tx) had significant improvements in neurological severity score (NSS), and wire-grip and motion test (WGMT). However 14-laser Tx provided no benefit over TBI-sham control. Mice receiving 1- and 3-laser Tx had smaller lesion size at 28-days (although the size increased over 4 weeks in all TBI-groups) and less Fluoro-Jade staining for degenerating neurons (at 14 days) than in TBI control and 14-laser Tx groups. There were more BrdU-positive cells in the lesion in 1- and 3-laser groups suggesting LLLT may increase neurogenesis. Transcranial NIR laser may provide benefit in cases of acute TBI provided the optimum treatment regimen is employed.
authors: Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, Massachusetts, United States of America.
authors: Weijun
authors: W
authors: Xuan
authors: Fatma
authors: F
authors: Vatansever
authors: Liyi
authors: L
authors: Huang
authors: Qiuhe
authors: Q
authors: Wu
authors: Yi
authors: Y
authors: Xuan
authors: Tianhong
authors: T
authors: Dai
authors: Takahiro
authors: T
authors: Ando
authors: Tao
authors: T
authors: Xu
authors: Ying-Ying
authors: YY
authors: Huang
authors: Michael R
authors: MR
authors: Hamblin
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000528:radiation effects; D001930:Brain Injuries / Q000473:pathology / Q000523:psychology / Q000532:radiotherapy*; D001973:Bromodeoxyuridine / Q000378:metabolism; D049109:Cell Proliferation / Q000528:radiation effects; D004195:Disease Models, Animal; D005452:Fluoresceins; D005456:Fluorescent Dyes; D028022:Low-Level Light Therapy; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D009043:Motor Activity / Q000528:radiation effects; D055495:Neurogenesis / Q000528:radiation effects*; D009474:Neurons / Q000473:pathology / Q000528:radiation effects*; D012107:Research Design
chemical_list: D005452:Fluoresceins; D005456:Fluorescent Dyes; C435731:fluoro jade; D001973:Bromodeoxyuridine