Exploring immunomodulatory peptides from monkfish (Lophius litulon) roe: Identification, in vitro activity, and molecular docking analysis.

To facilitate the high-value utilization of monkfish (Lophius litulon) roe, the immunomodulatory impact of its active peptides was thoroughly investigated. The sequence of immunomodulatory peptides was successfully identified by utilizing low molecular weight derived from monkfish roe (MRP) and employing LC-MS/MS. The efficacy of these peptides on RAW 264.7 cells was evaluated through measurements of cellular proliferation rates, phagocytic activity, nitric oxide (NO) levels, and cytokine secretion. Molecular docking techniques were employed to theoretically analyze the interactions to further elucidate the underlying immunomodulatory mechanisms. MRP was identified using LC-MS/MS, leading to the eventual screening of four immunomodulatory peptides (FRF, LWR, LFP, and PLW). These oligopeptides exhibited robust immunomodulatory properties, significantly boosting the proliferation and phagocytic functions of RAW 264.7 cells, along with markedly enhancing the secretion of NO, interleukin-1 beta (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor (TNF-α). The molecular docking analysis revealed that these four peptides exhibited strong binding affinities with toll-like receptor 2 (TLR2) and TLR4, thereby exerting their immunomodulatory effects. In summary, the four peptides (FRF, LWR, LFP, and PLW) identified from monkfish roe exhibit promising immunomodulatory effects and have potential as food-derived immunomodulators.