Carbon Arc Lamp Therapy Enhances The Repair Potential Of Chronic Soft Tissue Injury In Rats Compared With The Ability Of Photobiomodulation Therapy

Objective: The effects of photobiomodulation therapy (PBMT) and carbon arc lamp therapy (CALT) on the repair of chronic soft tissue injury were compared.Background data: PBMT improves soft tissue repair of chronic injury. However, there has been no research on the effect of CALT.Methods: Human umbilical vein endothelial cells (HUVECs) were irradiated using PBMT and CALT at 2 J/cm(2) to observe their effects on cell proliferation and migration. The effects of PBMT and CALT on soft tissue injury repair were assessed using a chronic gastrocnemius injury model of the posterior limb in rats. The malondialdehyde (MDA), superoxide dismutase (SOD), and prostaglandin E2 (PGE2) were examined by biochemical analyses. The degree of tissue damage repair was evaluated by the immunohistochemical method [CD45, CD34, vascular endothelial growth factor (VEGF), and actin] and the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) method.Results: Treatment by PBMT and CALT significantly accelerated the proliferation and migration of HUVECs. Moreover, significant decreases in the contents of MDA and PGE2 were observed in the PBMT and CALT groups, while SOD activity was increased. The histological assessment shows that the content of inflammatory cells and apoptotic cells significantly decreased in the CALT group. However, the microvascular density, VEGF content, and actin content were increased in the CALT group.Conclusions: The results demonstrate that CALT has a stronger effect on promoting chronic soft tissue injury repair in comparison with PBMT.