Effects of DMSO on Rabbit Ear Hypertrophic Scar Model: A Controlled Randomized Experimental Study

Abstract Dimethylsulfoxide (DMSO) is an anti-inflammatory, anti-bacterial, analgesic drug that is widely used to treat several diseases in literature. It has a detractive effect to collagen deposition in abnormal tissue. The aim of this study was to investigate the possible therapeutic effects of the DMSO in the hypertrophic scar formation in rabbit. Twenty-four New Zealand male albino rabbits were randomly divided into four groups: control, sham, DMSO, and TRA (triamcinolone acetonide). Except control group, punch biopsy defects were created on each animal’s right ear. Following the hypertrophic scar formation at day 28, intralesional DMSO and triamcinolone acetonide was administrated once a week for four weeks into these scars of the DMSO and TRA groups, respectively. No therapeutic agent was administered to the control and sham groups. One week after the last injection, ear samples were collected for histopathological, immunohistochemical, and real-time polymerase chain reaction (RT-PCR) gene expression analyses. Histopathological examination revealed that the epithelium in the DMSO group was thicker than in the control and TRA groups; but thinner than in the sham group. Connective tissue thickness value and vascularity level value of the sham group was higher than control, DMSO, and TRA group values. Collagen type I immunoreactivity level values of the sham and TRA groups was higher than control and DMSO group values. Collagen type III immunoreactivity was higher in sham group than all other groups. Collagen type I/type III immunoreactivity ratios were lower in DMSO group. Collagen alignments were natural in the DMSO group, but they were irregular in the sham and TRA groups. The collagen type I gene expression level values of the DMSO and TRA groups were lower than the results of the sham group. Collagen type III, and IFN-γ mRNA expression values were almost similar among the groups. TGF-1β mRNA expressions were higher in DMSO and TRA groups than control and sham groups. In conclusion, it can be said that intralesional administration of the DMSO could decrease the hypertrophic scar formation easely and safely.