MicroRNA-421 affects the chemotaxis of monocytes via MCP-1, and regulates the local immune responses in injured cartilage site of elbow joint of upper limbs

• Main Authors: Feng Zhu, Jie Yin, Junjie Li, Jianbo Xue
• Format: Article
• Language: English
• Published: Taylor & Francis Group 2020-01-01
• Series: Biotechnology & Biotechnological Equipment
• Subjects: mir-421; mcp-1; cartilage injury; immune response
• Online Access: http://dx.doi.org/10.1080/13102818.2020.1738955
• ISSN: 1310-2818; 1314-3530

The aim of the present study was to determine the expression of MCP-1 in injured cartilage tissues, peripheral blood and synovial fluid from patients with cartilage injury of elbow joint of upper limbs, and try to understand its relationship with microRNA (miRNA or miR)-421. Twenty-eight patients and 26 healthy subjects were included. Injured cartilage tissues and peripheral blood were collected from all 28 patients. Synovial fluid was collected from 12 patients with elbow effusion. The expression of mRNA and miR-421 was determined by quantitative real-time polymerase chain reaction (qRT-PCR); the expression of MCP-1 protein in tissues, by western blotting; MCP-1 in serum or synovial fluid, by enzyme-linked immunosorbent assay (ELISA). Dual luciferase reporter assay was used to identify direct interaction between miR-421 and MCP-1. The migration of THP-1 cells was determined by transwell assay. The results showed that MCP-1 was elevated in patients with cartilage injury of elbow joint of upper limbs. By contrast, miR-421 was decreased. miR-421 could bind with the 3′-UTR seed region of MCP-1 mRNA to regulate its expression. Overexpression of miR-421 inhibited the expression of MCP-1 in HC-a cells, and the chemotaxis of THP-1 monocytes. This study demonstrates that the up-regulation of MCP-1 in injured cartilage tissues, serum and synovial fluid from patients with cartilage injury of elbow joint of upper limbs was related to the down-regulation of miR-421. In addition, miR-421 may affect the chemotaxis of monocytes via MCP-1, and regulate the local immune responses in injured cartilage site of elbow joint of upper limbs.