Atheroprotective effect of novel peptides from Porphyridium purpureum in RAW 264.7 macrophage cell line and its molecular docking study.

Objective To explore the atherogenic foam cell
prevention efficiency of two dipeptides purified from
Porphyridium purpureum on RAW 264.7 cell line and
to study its molecular interaction through molecular
docking.
Result P. purpureum consists of 29.9% protein and
2.98% phycoerythrin on a dry weight basis. The two
dipeptides namely of Histidine–Glutamic acid (HE)
and Glycine–Proline (GP) isolated from the total
protein and purified phycoerythrin of P. purpureum
respectively, were evaluated for atherogenic foam cell
prevention capacity in RAW 264.7 cell line. The IC5O
values of peptides were found to be 91.2 ± 1.81 lg/
ml (GP), 103.3 ± 4.8 lg/ml (HE) in MTT assay. The
two peptides reduce the foam cell formation, intracellular
lipid accumulation (cholesterol and triglycerides)
and the secretion of TNF-a and IL-6 which are
inflammatory cytokines in RAW 264.7 cell line at
non-cytotoxic concentrations. A molecular interaction
study proposed the binding pose for GP and HE
peptides targeting the scavenging receptors CD36,
SRA1, and Map Kinase p38 (a protein mediator).
Conclusions The cell line and molecular docking
study indicated that among the two dipeptides, peptide
GP has the highest atherogenic foam cell prevention
efficiency.