Collagen synthesis and MicroRNA interaction in degenerative lumbar canal stenosis

To investigate the potential interaction between collagen synthesis and microRNAs in ligamentum flavum (LF) obtained from patients with degenerative lumbar canal stenosis (DLCS). A total of thirty-two human LF specimens were divided into two groups, each based on the diagnosis as follows: 20 from patients with DLCS and 12 from patients those with lumbar disc herniation (LDH). Fibrosis was graded into four levels according to the accumulation of decreased elastin fibres and increased collagen fibres, which can be observed using the Masson’s trichrome staining. Expression of the collagens (COL1A1, COL1A2, COL3A1, COL5A1, COL5A2, COL6A1, COL8A1), associated proteins (extracellular matrix protein tenascin XB-TNXB, solute carrier family 39 member 13-SLC39A13, and procollagen N proteinase ADAMTS-2; and micro-ribonucleic acids (miR-27B, miR-29B, miR-143, and miR-221) were measured by quantitative real-time polymerase chain reaction (qRT-PCR) analysis. Western blot analysis was performed to determine the levels of COL1, COL3, COL5, COL6A1, and COL8A1. DLCS patients have higher fibrosis score than the LDH patients. DLCS patients have higher fibrosis score than the LDH patients. qRT-PCR analysis demonstrated that strongly upregulated mRNA levels of COL1A, COL1A2, COL3A1, ADAMTS2, miR-29B, and miR-143. However, protein expressions of COL1, COL3, COL6A, and COL8A1 is also upregulated. Our results identified miR-29B and miR-143 regulation of COL synthesis of the LF fibrosis.