چکیده (انگلیسی):

Objective: To observe the influence of different concentrations of homocysteine (Hcy)
and hydrogen sulfide (H2S) on the secretion and activation of matrix metalloproteinase-2
(MMP-2) in cardiocytes so as to search for new ways to fight against myocardial tissue
fibrosis.
Methods: Cardiocytes H9C2 was cultured in vitro and different concentrations of Hcy
and H2S were added for 6-h and 24-h cultivation. MTT cell proliferation assay was
applied to test the activation change of cardiocytes H9C2 after affecting by different
concentrations of Hcy and H2S. ELISA and MTT were employed to detect the expression
and enzymatic activity of MMP-2.
Results: The H9C2 cell inhibition of activity was more significant with 1000 mmol/L of
Hcy as compared with other concentrations (P < 0.001). With 2.5–100.0 mmol/L Hcy and
0.1, 1.0 and 10.0 mmol/L H2S, the activity of H9C2 did not change significantly (P > 0.05).
Hcy with concentrations of 10, 50 and 100 mmol/L could increase the quantity of MMP-2
secreted by cardiocytes H9C2, and the interaction strength was concentration-dependent
(P < 0.05). After interacting with 100 mmol/L of Hcy for 6 h, the zymogen activation
effect of MMP-2 was stronger than that of the 2.5–25 mmol/L group (P < 0.05). After
interacting with Hcy and H2S (1.0 mmol/L) for 6 h and 24 h, the activation effect of MMP-2
was stronger than those interacted with 10, 25, 50 and 100 mmol/L of Hcy (P < 0.05).
Conclusions: Hcy can increase the production of MMP-2 secreted by H9C2 cell and
improve its zymogen activation. Besides, the interaction strength is concentrationdependent;
while H2S can up-regulate the activation of MMP-2 and co-promote the
activation of MMP-2 with Hcy as well.