Protective Effect of Melissa officinalis (Lemon Balm) Extract on Cytokine Levels and Oxidative Stress in Ovalbumin Induced Lung Toxicity in Rats.

This study assessed the effects of a hydroalcoholic extract derived from Melissa officinalis (lemon balm) at doses of 50, 100 and 200 mg/kg in a rat model of experimental allergic asthma. We evaluated biomarkers of oxidative stress, including nitrite (NO2), malondialdehyde (MDA), thiol (SH), superoxide dismutase (SOD) and catalase (CAT), along with mediators such as interleukin-4 (IL-4), IL-17, interferon-gamma (IFN-γ) and immunoglobulin E (IgE) in bronchoalveolar lavage fluid (BALF). The untreated asthmatic group showed significantly elevated levels of MDA, NO2, IL-4, IL-17 and IgE (p < 0.001), while levels of SH, IFN-γ and the activities of SOD and CAT were markedly reduced compared with the control group. In contrast, treatment groups receiving plant extracts and dexamethasone (Dex) demonstrated a significant decrease in levels of NO2, MDA, IL-4, IL-17 and IgE. Additionally, the levels of SH, IFN-γ and the activities of SOD and CAT were significantly elevated compared with the untreated asthmatic group (p < 0.05 to p < 0.001). The therapeutic efficacy of Melissa officinalis extract in reducing oxidative damage and inflammatory mediators in asthmatic rats was comparable to that of dexamethasone. This finding highlights the potential therapeutic benefits of the plant in alleviating asthma-related symptoms.