Investigation of the effect of terahertz radiation on acute wounds in mice

LIN Yijing; LIN Min; CHEN Chunhai; MA Qinlong; ZHANG Yiming

doi:10.3969/j.issn.1673-7040.2025.02.008

Abstract：Objective To investigate the effect of terahertz radiation on acute wounds and its potential mechanism.Methods Six-teen 6 to 8 weeks C57BU6 J mice were randomly divided into the irradiated group and control group,8 mice in each group,to establish an acute whole skin defect trauma model.The wounds of the irradiated group received terahertz exposure with an average power density of 110 mW/cm2 for 10 min/hole(20 min/each),and the wounds of the control group were exposed to air in the same experimental environment for 20 min/each.Wound healing was recorded by taking photos immediately after exposure,on day 1 and day 3,and the residual area was quantified and analyzed by Image J.The width of the wound,average thickness of epidermis,thickness and area of granulation tissue were analyzed by HE staining,and the collagen content and type of the wound were analyzed by Masson staining and Sirius red staining.Im-munohistochemical staining was performed to analyze IL-10,IL-1 β,CD31,Collagen Ⅲ,and Ki-67 indexes.Results The semi-quanti-tative analysis of the residual wound area showed that the wound healing rate of the irradiated group was higher than that of the control group on both day 1 and day 3,and the difference was significant on day 1(P＜0.01).HE staining showed that the length and average thick-ness of the new epidermis in the irradiated group were higher than those in the control group on days 1 and 3,and the difference was signif-icant on day 3(P＜0.0001).Masson staining showed that the percentage of new collagen in the irradiated group was higher than that in the control group,and the difference was significant at the edge of the wound(P＜0.0001).Sirius red staining showed that the proportion of typeⅢ collagen/type Ⅰ collagen was higher in the irradiated group than in the control group(P＜0.05).Immunohistochemistry results suggested that the percentage of IL-1β positive area was lower in the irradiated group than in the control group,but the difference was not significant(P＞0.05).The percentage of IL-10,Collagen Ⅲ,CD31,and Ki-67 positive area was significantly higher in the irradiated group than in the control group(P＜0.0001,P＜0.05,P＜0.01,and P＜0.0001).Conclusion Terahertz radiation was able to attenuate the inflammatory re-sponse,promote the formation of neovascularization in wounds,and promote collagen production and re-epithelialization in mouse skin wounds.