Sulforaphane represses matrix-degrading proteases and protects cartilage from destruction in vitro and in vivo

Davidson RK, Jupp O, de Ferrars R, Kay CD, Culley KL, Norton R, Driscoll C, Vincent TL, Donell ST, Bao Y, Clark IM · Arthritis and Rheumatism

The paper the whole topic rests on. Sulforaphane suppressed cytokine-induced metalloproteinase expression in human chondrocytes and synovial cells, and abolished cytokine-driven destruction of cartilage explants at both the proteoglycan and the collagen level. In DMM mice, a sulforaphane-rich diet lowered the arthritis score and blocked the early gene-expression changes. Mechanistically it worked through NF-κB inhibition and prolonged JNK/p38 activation, and — against the usual assumption — independently of Nrf2.

Population

Primary human articular chondrocytes and synovial cells, bovine nasal cartilage explants, and DMM-model mice

Intervention

Sulforaphane, 10 μM in explants; an SFN-rich diet supplying 3 μmol/day in mice

Comparator

Cytokines alone; control chow

Limitations

Explants are bovine nasal, not articular. The mouse arm is a dietary dose chosen by the investigators, not one derived from human intake.