Quercetin decreases proliferation of orbital fibroblasts and their release of hyaluronic acid.

BACKGROUND

Inhibition of fibroblast (FB) proliferation and hyaluronic acid (HA) production may be a therapeutic approach to Graves' ophthalmopathy (GO). The flavonoid quercetin has a wide range of activities, including reduction of FB growth.

OBJECTIVE

To investigate the effects of quercetin in orbital FB from GO patients and control subjects.

METHODS

Primary cultures of orbital FB were treated with quercetin or with its glycosides rutin and quercitrin. Cell proliferation, necrosis, apoptosis, HA production, and cell cycle were measured.

RESULTS

Beginning at a 30 μM concentration, quercetin, but not rutin and quercitrin, reduced cell proliferation, with no difference between GO and control FB. The effect of quercetin on proliferation was due to necrosis and cell cycle blockade, whereas apoptosis was unaffected. Quercetin reduced HA in the cell media, with no difference between GO and control FB.

CONCLUSIONS

Quercetin reduces cell proliferation and HA release in orbital FB. Whether these initial findings have any potential for the use of quercetin in the clinical practice remains to be established.