Epigenetics refers to a heritable change genetic code that is mediated by a mechanism specifically not due to alterations in the primary nucleotide sequence. These epigenetic changes can lead to medical condition changes. Recent studies have shown that epigenetic modifications orchestrate the epithelial-mesenchymal transition and eventually fibrosis of the renal tissue.
MicroRNAs( miRNAs) have been the focus of many renal disease spectrums from glomerular diseases to transplant rejection. A recent study in Experimental and Molecular Pathology is one of the first to examine the role of miRNAs in HIVAN. The investigators showed that 11 miRNA were downregulated in HIVAN when compared to controlled mice. Further examination showed that miR-200 and miR-33 were the two that had effects on the podocytes specifically.
This begs a question of looking at miRNA in many renal diseases. Another study recently published looked at urinary miR-21, miR-29 and miR-93 as novel biomarkers of fibrosis in patients with IgA nephropathy. Lupus Nephritis had miR-638, miR-198 and miR-146a compared to controls.
Interestingly. miR-155 and miR-126 are elevated in ESRD patients as potential markers of inflammation. miRNAs have been studied in diabetic nephropathy as well.
The list can go on and on... And we are sure to see more role of miRNA in clinical use perhaps in near renal future. Still unclear is how these numbers will be very helpful. Repeat studies to confirm that certain miRNA are markers for lupus flare versus diabetic nephropathy are needed. They might assist in a decision to biopsy or not to biopsy? Or are they mere markers of prognosis. More global decision has to be made on how to use these tests in future use:- markers, or targets for potential treatments....
MicroRNA Sequence Profiles of Human Kidney Allografts With or Without Tubulointerstitial Fibrosis. Transplantation Dec 15, 2012