Allicin Ameliorated IMQ-Induced Psoriasis-like Skin Lesion in Mice
IMQ-treated mice skin exhibited typical psoriatic characteristics, such as acanthosis, inflammatory cell infiltrates, and altered dermal vascularity. Therefore, IMQ was applied to mouse skin to explore how allicin interferes with the pathophysiology of psoriasis. To assess allicin’s effect on restoring the appearance of psoriatic lesions induced by IMQ, we consecutively applied IMQ for six days after shaving the back of mice. The treatment groups received mixed ointment with different allicin contents four and eight hours after receiving IMQ (Figure 1A). Compared with the normal control group, IMQ treatment exhibited apparent erythema and scaling of the skin, whereas the phenotypic changes in allicin-treated groups were significantly improved (Figure 1B). Dorsal skin thickness, erythema and scaling were scored daily from 0-4 according to the severity degree. Additionally, an overall evaluation of skin lesions was depicted by a modified PASI score (0-12), calculated by summing the three individual scores. Compared with the IMQ-group, allicin-treated groups showed a significant alleviation in erythema severity (Figure 1C), scaling (Figure 1D), and thickening (Figure 1E). Figure 1F showed a better overall improvement with allicin treatment than positive control groups. H&E staining showed that the epidermal layer of the IMQ-treated group was significantly incrassated, and the corium layer was infiltrated by inflammatory cells accompanied by vascular hyperplasia. However, the characteristic pathological changes of the skin in the allicin-treated groups were significantly improved compared with the model group (Figure 1G, H). These results collectively indicated that allicin was efficient in relieving IMQ-induced psoriasis-like lesions.