Lovastatin impairs cellular proliferation and enhances hyaluronic acid production in fibroblast-like synoviocytes

Statins have demonstrated chondroprotective effects by reducing inflammation and mitigating extracellular matrix degradation. However, statins are also reported to be cytotoxic to several types of cells. Early-onset osteoarthritis (OA) is characterized by synovial inflammation, which adversely affects hyaluronan (HA) production in fibroblast-like synoviocytes (FLSs). Nevertheless, the precise effects of statins on the synovium remain unclear.

This study investigated the impact of lovastatin on human FLSs, and HA secretion-related genes, signaling pathways, and production were evaluated.

The findings revealed that high doses of lovastatin (20 or 40 μM) decreased FLS viability and increased cell death. FLS proliferation ceased when cultured in a medium containing 5 or 10 μM lovastatin. mRNA expression analysis demonstrated that lovastatin (5 and 10 μM) upregulated the gene level of hyaluronan synthase 1 (HAS1), HAS2, and proteoglycan 4 (PRG4), but not HAS3. While the expression of multidrug resistance-associated protein 5 transporter gene remained unaffected, both inward-rectifying potassium channel and acid-sensing ion channel 3 were upregulated. Western blot further confirmed that lovastatin increased the production of HAS1 and PRG4, and activated the PKC-α, ERK1/2, and p38-MAPK signaling pathways. Additionally, lovastatin elevated intracellular cAMP levels and HA production in FLSs.

Lovastatin impairs cellular proliferation but enhances HA production in human FLSs.