Investigation of the Anti-inflammatory Properties of Ethanol Extract of Citrus aurantifolia (Lime) in an Imiquimod-Induced Psoriasis Rat Model

Abstract

Background: Psoriasis is a chronic inflammatory skin disorder characterized by immune dysregulation and increased levels of inflammatory biomarkers such as C-reactive protein (CRP) and interleukin-17 (IL-17). Ethanol extract of Citrus aurantiifolia contains bioactive compounds that may exhibit anti-inflammatory effects. This study aims to evaluate the effect of Citrus aurantiifolia ethanol extract on CRP and IL-17 levels in an imiquimod-induced psoriasis rat model.

Methods: This experimental study utilized 25 rats, which were randomly assigned into five groups: normal control group (K1), imiquimod-induced psoriasis group (K2), and three treatment groups receiving imiquimod along with 1%, 3%, and 5% ethanol extract of Citrus aurantiifolia (K3, K4, K5). Psoriasis was induced by topical application of imiquimod, and the extract was administered topically. After treatment, CRP and IL-17 levels were measured using the ELISA method.

Results: The levels of CRP and IL-17 were significantly higher in the imiquimod-induced psoriasis group compared to the control group (p<0.05). Treatment with Citrus aurantiifolia ethanol extract significantly reduced CRP and IL-17 levels in groups K3, K4, and K5 compared to the imiquimod-only group (p<0.05), with the highest reduction observed in the 5% extract group.

Conclusion: Ethanol extract of Citrus aurantiifolia demonstrates significant potential as an anti-inflammatory and immunomodulatory agent by reducing CRP and IL-17 levels in the imiquimod-induced psoriasis rat model. Although the imiquimod-induced psoriasis rat model does not fully replicate the complexity of human psoriasis, these findings provide promising groundwork for the development of natural therapies. Further research is needed to validate these findings, explore the underlying mechanisms, and optimize dosing.