A Preliminary Study on Quantitative Analysis of Collagen and Apoptosis Related Protein on 1064 nm Laser-Induced Skin Injury

Simple Summary With the rapid progress of laser technology and its expanding applications, there is a growing need for detailed information regarding its effects on living tissue and the treatment of skin damage caused by this kind of radiation. Both collagen levels and apoptosis-related protein expressions were quantitatively and comparatively analyzed in porcine skin injuries induced by laser exposure. The findings revealed skin injuries primarily manifested as white spots and burnt spots. There was a progressive increase in the size and depth of skin damage as the laser dosage was elevated. Laser-induced apoptotic cells in porcine skin injuries were significantly increased in the late stages of healing. Subjection to a 1064 nm laser led to a decline in skin healing efficiency as the radiation dosage escalated, leading to disrupted collagen arrangement and inadequate collagen content. Heightened Bax, caspase-3, and caspase-9 protein expressions in healing skin tissues were directly linked to escalated cell apoptosis.Abstract To investigate the associated factors concerning collagen and the expression of apoptosis-related proteins in porcine skin injuries induced by laser exposure, live pig skin was irradiated at multiple spots one time, using a grid-array method with a 1064 nm laser at different power outputs. The healing process of the laser-treated areas, alterations in collagen structure, and changes in apoptosis were continuously observed and analyzed from 6 h to 28 days post-irradiation. On the 28th day following exposure, wound contraction and recovery were notably sluggish in the medium-high dose group, displaying more premature and delicate type III collagen within the newly regenerated tissues. The collagen density in these groups was roughly 37-58% of that in the normal group. Between days 14 and 28 after irradiation, there was a substantial rise in apoptotic cell count in the forming epidermis and granulation tissue of the medium-high dose group, in contrast to the normal group. Notably, the expression of proapoptotic proteins Bax, caspase-3, and caspase-9 surged significantly 14 days after irradiation in the medium-high dose group and persisted at elevated levels on the 28th day. During the later stage of wound healing, augmented apoptotic cell population and insufficient collagen generation in the newly generated skin tissue of the medium-high dose group were closely associated with delayed wound recovery.