CoQ10 supplementation: a new treatment modality in steroid-resistant nephrotic syndrome with unknown molecular etiology

Steroid-resistant nephrotic syndrome (SRNS) is a common problem in paediatric nephrology practice which tends to progress to end-stage renal disease. SRNS-causing genes are expressed in the glomerular podocyte which is a specialized cell type. However, there are more than 80% of SRNS cases with unknown molecular etiology. Coenzyme Q10 (CoQ10) has an important role in the mitochondrial electron-transport chain. The synthesis of CoQ10 is a complex pathway, involving enzymes from various genomes; termed from CoQ1 to CoQ10. Due to sequenced reactions of synthesis, the enzymes and regulatory proteins are needed in obligation. So any dysfunction; affects the biosynthesis of CoQ10. The authors described quinone-responsive six patients having CoQ2 mutations, presented with steroid-resistant NS. CoQ 10 deficiency is strongly related with CoQ2 deficiency and/or any mutation of encoding genes. Among the 5 types of CoQ 10 deficiency, infantile form can be presented only with renal involvement, nephrotic syndrome. Also in other forms, the renal involvement is not rare besides the neurological pathologies.