Identifying chondroprotective diet-derived bioactives and investigating their synergism

Davidson RK, Green J, Gardner S, Bao Y, Cassidy A, Clark IM · Scientific Reports

Screens food compounds against cartilage endpoints side by side rather than one at a time, and then asks whether mixing them helps. Four compounds came through the screen: sulforaphane, apigenin, isoliquiritigenin and luteolin, each cutting interleukin-1-driven metalloproteinase expression and aggrecan loss from explants. On mixtures the answer runs mostly the other way. Of the six pairs, only sulforaphane with isoliquiritigenin was synergistic against MMP13 (combination index 0.724); two were nearly additive, and the three pairs containing luteolin were antagonistic. Every combination of three or four compounds was antagonistic.

Population

Primary human articular chondrocytes from three or more donors, two human chondrocyte cell lines, and bovine nasal cartilage explants

Intervention

96 diet-derived compounds screened individually, then the four most active tested in every pairing and larger mixture

Comparator

Interleukin-1-stimulated cells and explants without a compound

Limitations

Cell-level screening, three donor isolates per experiment, and the explant work is bovine nasal cartilage rather than human articular. Synergy in a dish does not establish that the same combination is reachable by eating, or that it does anything to a joint — and for most of the mixtures this paper tested, the dish said the mixture was worse than its parts. Funded by the BBSRC Diet and Health Research Industry Club; no competing interests declared.