Abstract
Although chloroquine and diclofenac are not cardiovascular drugs, their chronic administration may trigger cardiotoxicity. We, therefore, evaluated the cardiotoxic impact of diclofenac in chloroquine-treated adjuvant arthritic rats and the protective role of Rho-kinase inhibitors.
90 male rats were equally distributed into 9 groups including control. Arthritis was induced by S.C injection of Complete Freund's adjuvant in hind paw plantar surface. Arthritic rats were subdivided into 8 groups, orally treated with: no drug, chloroquine (50 mg/kg), diclofenac sodium (1 mg/kg) and chloroquine + diclofenac. To study the role of Rho-kinase in chloroquine/diclofenac-triggered cardiotoxicity, four arthritic groups were also co-treated with Rho-kinase inhibitors (fasudil or atorvastatin) along with diclofenac and chloroquine + diclofenac.
All treatments significantly elevated serum cardiac injury and dysfunction markers as well as left ventricular malondialdehyde but depleted antioxidants with the greatest effect in the combination group. Chloroquine and/or diclofenac; in particular, their combination shifted the balance between left ventricular pro- and anti-apoptotic proteins towards myocardial apoptosis. Surprisingly, treatment with diclofenac or chloroquine/diclofenac markedly up-regulated cardiac RhoA and Rho-kinase1. Such up-regulation was coupled with a greater increase in cardiac oxidative damage biomarkers in the combination group than in individually-treated ones. However, Rho-kinase inhibition protected against diclofenac-induced increase in myocardial oxidative damage markers.
Diclofenac greatly amplified cardiac oxidative damage in chloroquine-treated arthritic rats via up-regulation of Rho-kinase1. However, Rho-kinase inhibitors provided cardioprotection against diclofenac toxicity. Overall, they could be used as safer adjuvants to diclofenac during the treatment of rheumatoid arthritis with chloroquine.
•Diclofenac amplified cardiac oxidative damage in chloroquine-treated arthritic rats via up-regulation of Rho-kinase1.•Rho-kinase inhibitors provided cardioprotection against diclofenac toxicity.•Rho-kinase inhibitors could be safer adjuvants to chloroquine and diclofenac during rheumatoid arthritis.