Determination of miRNA-199a and its Target Genes in Degenerative Lumbar Intervertebral Disc

Low back pain (LBP) remains among the most common causes of disability and physician referral worldwide. The pathophysiology of the intervertebral disc degeneration (IDD) remains elusive which requires further research. MicroRNAs are short nucleoid intracellular players on various physiologic and pathophysiologic processes in human body. The aim of the current study was to determine the expression profile of miRNA-199a-5p in IDD and its correlation to the grade of IDD. This case-controlled study was conducted during a 6-month period from 2017 to 2018 in two university hospitals in Shiraz, Iran. We included 15 patients with grade 3 and 4 0 of Pfirrmann and 5 patients with traumatic lumbosacral fractures with grade I. Total discectomy was performed in all the individuals and the samples were sent to the laboratory. The NP cells were isolated and the RNA was extracted. cDNA was synthesized by reverse transcriptase and the expression was measured using real-time polymerase chain reaction (RT-PCT). The expression was analyzed according to Ct technique. We overall included 20 patients in two study groups. Both study groups were comparable regarding the baseline and clinical characteristics expect for age (p=0.026). The fold change (p=0.007) and relative expression (p=0.012) of the miRNA-199a-5p was found to be significantly higher in patients compared to controls. The fold change (p=0.001) and relative expression (p<0.001) were also associated with the Pfirrmann grading. We found that the area under curve (AUC) was 0.880 (95%CI: 0.721-0.938) indicative of moderate accuracy. Expression of the miRNA-199a-5p is increased in the IDD. The expression of the miRNA-199a-5p was also associated with the grade of the degeneration based on the Pfirrmann grading. The diagnostic accuracy of the miRNA199a-5p as a biological marker of the IDD was also found to be of moderate.

Keywords:

Intervertebral Disc Degeneration , MicroRNA-199a , Target Genes , Pfirrmann Grade