Protective effect of erucic acid against cyclophosphamide-induced immunosuppression <i>via</i> IFN-γ/TNF-α/IgG pathways: <i>in vivo</i> network pharmacology-based analysis, and molecular docking

Erucic acid is a monounsaturated omega-9 fatty acid with reported immunomodulatory activity. This study evaluated its protective effects against cyclophosphamide (CTX)-induced immunosuppression in mice. Thirty animals were divided into six groups: normal control, CTX (80 mg kg^-1), erucic acid (10 and 20 mg kg^-1), levamisole (20 mg kg^-1), and an erucic acid-only group (20 mg kg^-1). Immune organ indices, hematological parameters, cytokines, oxidative stress markers, IgG levels, and splenic lymphocyte proliferation were measured, along with histological assessment of the spleen and thymus. Network pharmacology was used to predict immune-related targets and docking affinities. CTX reduced the spleen index from 7.26 ± 0.75 mg g^-1 to 3.04 ± 0.21 mg g^-1 and the thymus index from 3.60 ± 0.32 mg g^-1 to 1.50 ± 0.21 mg g^-1. Lymphocyte proliferation dropped from 100.0 ± 3.28% to 37.50 ± 3.07%. WBC and RBC counts declined to 2.53 ± 0.30 × 10³ µL^-1 and 4.33 ± 0.69 × 10⁶ µL^-1, respectively. CTX also lowered IFN-γ (3.50 ± 0.19 to 1.80 ± 0.19 ng mg^-1), TNF-α (105.0 ± 5.56 to 52.0 ± 5.56 pg mL^-1), and IgG levels (12.00 ± 0.54 to 4.70 ± 0.54 pg mL^-1), while increasing MDA (1.42 ± 0.16 to 4.88 ± 0.41 nmol mg^-1) and NO (0.10 ± 0.01 to 0.24 ± 0.01 µmol g^-1). Erucic acid at a 20 mg kg^-1 dose increased the spleen index to 6.63 ± 0.60 mg g^-1, the thymus index to 3.00 ± 0.22 mg g^-1, and the lymphocyte proliferation to 61.67 ± 3.44%. It improved WBC counts to 4.72 ± 0.29 × 10³ µL^-1 and restored IFN-γ (3.28 ± 0.22 ng mg^-1), TNF-α (87.0 ± 5.56 pg mL^-1), and IgG (9.03 ± 0.87 pg mL^-1). Antioxidant markers also improved, with SOD rising from 5.55 ± 0.52 to 10.22 ± 1.02 U mg^-1 and GSH from 3.13 ± 0.35 to 6.45 ± 0.46 µmol g^-1. Histology showed reduced splenic and thymic damage in treated groups. Docking analysis indicated strong interactions between erucic acid and key immune-regulatory targets. Overall, erucic acid, particularly at a dose of 20 mg kg^-1, counteracted cyclophosphamide-induced immune suppression and oxidative stress, with effects comparable to those of levamisole.