Monotropein inhibits MMP9-mediated cardiac oxidative stress, inflammation, matrix degradation and apoptosis in a mouse and cell line models of septic cardiac injury.

BACKGROUND

Sepsis can cause severe cardiac damage, and matrix metalloproteinase 9 (MMP9) is involved in the inflammatory response and tissue injury processes. Monotropein is a monoterpene glycoside with anti-inflammatory and antioxidant effects. This study aims to investigate whether monotropein can alleviate sepsis-induced cardiac injury by affecting the activity of MMP9.

METHODS AND RESULTS

The correlation between MMP9 and septic cardiac injury was explored using differential expression gene analysis from the GEO database and an in vitro lipopolysaccharide (LPS)-stimulated H9c2 cell model. In a cecal ligation and puncture (CLP)-induced mouse sepsis model, the effects of monotropein on myocardial cell apoptosis, inflammatory factor expression, and antioxidant enzyme levels were validated through drug administration. The results showed that MMP9 was significantly upregulated in sepsis patients. In the H9c2 cell model, LPS-induced MMP9 activity was positively correlated with cell damage. Inhibition of MMP9 alleviates LPS-induced myocardial matrix disruption and apoptosis. Monotropein exerts anti-matrix degradation and anti-apoptotic effects through MMP9 in LPS-induced H9c2 cells. Monotropein also reduced the expression of LPS-induced inflammatory factors (TNF-α, IL-1β, IL-6).In the mouse model, monotropein decreased oxidative stress damage (lower MDA levels, increased GSH, T-AOC, CAT enzyme activity), and improved cardiac injury by inhibiting myocardial cell apoptosis-related proteins (Bax, Bcl-2, and Caspase-3 activation).

CONCLUSION

Monotropein exerts a protective effect on septic cardiac injury by inhibiting MMP9 activity, reducing inflammatory response, and enhancing antioxidant capacity, thereby ameliorating myocardial cell damage and apoptosis.