Impact of Hyperhomocysteinemia on Cytokine and Matrix Metalloproteinases Contents in Rat Skeletal Muscle

Abstract

Background: High levels of homocysteine (Hcy) in the blood (hyperhomocysteinemia [HHcy]) are associated with many pathologies, including atherosclerosis, coronary heart disease, stroke, neurological disorders, and a decrease in muscle mass and strength. The present study aimed to evaluate the levels of pro- and anti-inflammatory cytokines and matrix metalloproteinases (MMPs) in skeletal muscle of rats with experimental HHcy. Methods: HHcy in rats of two age groups was induced by intragastric administration of D, L-thiolactone Hcy for 8 weeks. The criterion for the development of pathological conditions was a blood Hcy level above 15 mmol L−1. Cytokine and MMP levels in muscle homogenate were determined by enzyme-linked immunosorbent assay. Results: The findings of the study on the content of pro-inflammatory cytokines in skeletal muscles of rats with hyperhomocysteinemia indicated the following. For immature rats, the greatest reduction in tumor necrosis factor-α and interleukin-8 (IL-8) content was observed, whereas, for mature individuals, the most pronounced decline in IL-1b was evident in skeletal muscle tissue under the pathology state. The content of anti-inflammatory interferon-γ was also reduced in the muscles of both age groups by 30% compared to the control, besides a decrease in the content of collagenase MMP-1 was also observed. Conclusions: The presence of HHcy is associated with metabolic changes in skeletal muscles, which can result in a depletion of cytokines and a slowing down of proteolytic remodeling. This, in turn, can lead to the development of muscular abnormalities, including dysfunction, weakness, and muscle degeneration.

Keywords

• cytokines
• hyperhomocysteinemia
• matrix metalloproteinases
• skeletal muscle