4,5-Dicaffeoylquinic acid (4,5-DCQA) is a polyphenol originally isolated from
G. fagetorum and
G. pseudomollugo that has diverse biological activities, including anti-HIV replication, antioxidative, anti-inflammatory, and anti-melanogenic properties.
1,2,3,4,5 It inhibits HIV-1 integrase 3'' end processing, 3’ end joining, and disintegration with IC
50 values of 0.13, 0.24, and 0.3 μg/ml, respectively.
3 It also inhibits HIV-1 replication in MT-2 T lymphoblastoid cells with an EC
50 value of 2 μg/ml. 4,5-DCQA scavenges 2,2-diphenyl-1-picrylhydrazyl (DPPH; Item No.
14805) radicals in a cell-free assay (IC
50 = 19.8 μM) and inhibits superoxide production in human neutrophils activated by N-formyl-Met-Leu-Phe (fMLF; Item No.
21495) and cytochalasin B (Item No.
11328; IC
50 = 1.49 μM).
2 It decreases prostaglandin E
2 (PGE
2; Item No.
14010) production in LPS-stimulated U937 cells when used at concentrations of 5 and 10 μg/ml but increases it when used at 200 μg/ml and increases production of TNF-α at concentrations ranging from 5 to 200 μg/ml.
4 It inhibits the synthesis of MCP3 in U937 cells. 4,5-DCQA (25 μM) inhibits melanogenesis by 84% and decreases the levels of proteins involved in melanin biosynthesis, including tyrosinase, TRP-1, DCT, and MITF in B16F1 murine melanocytes.
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