Blue Mussel-Derived Bioactive Peptides PIISVYWK (P1) and FSVVPSPK (P2): Promising Agents for Inhibiting Foam Cell Formation and Inflammation in Cardiovascular Diseases

Atherosclerosis is a key etiological event in the development of cardiovascular diseases (CVDs), strongly linked to the formation of foam cells. This study explored the effects of two blue mussel-derived bioactive peptides (BAPs), PIISVYWK (P1) and FSVVPSPK (P2), on inhibiting foam cell formation and mitigating inflammation in oxLDL-treated RAW264.7 macrophages. Both peptides significantly suppressed intracellular lipid accumulation and cholesterol levels while promoting cholesterol efflux by downregulating cluster of differentiation 36 (CD36) and class A1 scavenger receptors (SR-A1) and upregulating ATP binding cassette subfamily A member 1 (ABCA-1) and ATP binding cassette subfamily G member 1 (ABCG-1) expressions. The increased expression of peroxisome proliferator-activated receptor-gamma (PPAR-γ) and liver X receptor-alpha (LXR-α) further validated their role in enhancing cholesterol efflux. Additionally, P1 and P2 inhibited foam cell formation in oxLDL-treated human aortic smooth muscle cells and exerted anti-inflammatory effects by reducing pro-inflammatory cytokines, nitric oxide (NO), prostaglandin E₂ (PGE₂), inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2), primarily through inhibiting NF-κB activation. Furthermore, P1 and P2 alleviated oxidative stress by activating the Nrf2/HO-1 pathway. Our findings demonstrate that P1 and P2 have significant potential in reducing foam cell formation and inflammation, both critical factors in atherosclerosis development. These peptides may serve as promising therapeutic agents for the prevention and treatment of CVDs associated with oxidative stress and inflammation.