METHODS: The MTT assay was utilized to analyze the effects of the test compounds on NRK-52E rat kidney epithelial cells. The detection of apoptosis and ability to scavenge free radicals was assessed via acridine orange-ethidium bromide (AO-EB) dual fluorescence staining, and 2,2-diphenyl-1-picrylhydrazyfree assay (DPPH), respectively. The ability of anti-inflammatory effect of the test compounds and western blot analysis against TGF-β, TNF-α, and IL-6 further assessed to determine the combinatorial efficacy.
RESULTS: Atorvastatin and quercetin treatment significantly lowered the expression of TGF-β, TNF-α, and IL-6 indicating the protective role in Streptozotocin-induced nephrotoxicity. The kidney cells treated with a combination of atorvastatin and quercetin showed green fluorescing nuclei in the AO-EB staining assay, indicating that the combination treatment restored cell viability. Quercetin, both alone and in combination with atorvastatin, demonstrated strong DPPH free radical scavenging activity and further encountered an anti-oxidant and anti-inflammatory effect on the combination of these drugs.
CONCLUSION: Nevertheless, there is currently no existing literature that reports on the role of QCT as a combination renoprotective drug with statins in the context of diabetic nephropathy. Hence, these findings suggest that atorvastatin and quercetin may have clinical potential in treating diabetic nephropathy.