Research on the effect of sulforaphane on inflammation and oxidative stress in myocardial tissue in rats with sepsis cardiomyopathy

At the same time, the number of deaths at each time point was recorded, and the changes in mortality rate were statistically analyzed.Two rats were randomly selected from each group for sacrifice, and their myocardial tissue was stained with HE. The damage and inflammatory infiltration of rat myocardial cells were observed under an optical microscope.ELISA was used to detect the serum cTnI and LDH concentrations in each group of rats, and the expression levels of TNF - α, IL-1 β, NO, and ROS in myocardial tissue were measured.

Western blot was used to measure the expression levels of TLR4 and Nrf2 proteins in rat myocardial tissue.Results Rats in the SCM group began to die after 8 hours, with an overall mortality rate of 90%. The mortality rate of SFN group rats was significantly reduced, with an overall mortality rate of 50%, and the difference was statistically significant (P<0.05). The expression levels of heart rate[（374.8±10.75）、（335.2±8.37）、（357.4±5.50）]、LVSP[（144.9±3.20））、（125.9±2.86）、（136.8±3.21）]、LVEDP[（8.1±0.42）、（11.9±0.95）、（9.1±0.43）]、+dp/dtmax[（3132±88.44）、（2618±46.17）、（2816±90.45）]、-dp/dtmax[（2459±73.08）、（1948±95.77）、（2285±109.4）]were statistically significantly different in three groups（F =54.901、95.190、94.335、111.104、76.477; all P＜0.01）.

Further comparison revealed that the heart rate, LVSP,+dp/dtmax, and - dp/dtmax of the SCM and SFN groups were lower than those of the Sham group (all P <0.01), while the LVEDP of both groups was higher than that of the Sham group (P <0.01). The heart rate, LVSP,+dp/dtmax, and -dp/dtmax of the SFN group were significantly increased compared to the SCM group (all P<0.01), while LVEDP was significantly decreased compared to the SCM group (P <0.01).

The differences in serum cTnI, serum LDH, myocardial tissue TNF-α, IL-1β, NO, and ROS expression among three groups of rats were statistically significant (F=1263.532, 57.782, 1130.698, 338.950, 155.727, 342.914, all P<0.01). Further comparisons revealed that the serum cTnI, serum LDH, myocardial tissue TNF -α, IL-1β, NO, and ROS expression in the SCM and SFN groups were significantly higher than those in the Sham group (all P<0.01), while those in the SFN group showed a significant decrease compared to the SCM group (all P<0.01).

Western-blotting showed that the expression of Nrf2 in the myocardial tissue of SCM group rats was lower than that of Sham group, while the expression of Nrf2 in the myocardial tissue of SFN group rats was significantly higher than that of SCM group (P<0.05). The expression of TLR4 in the myocardial tissue of SCM and SFN groups was significantly increased compared to the Sham group (P<0.05), while it was significantly decreased in the SFN group than in the SCM group (P<0.05).Conclusion Sulforaphane can alleviate myocardial inflammation and oxidative stress in rats with sepsis-induced cardiomyopathy and have a certain protective effect on myocardial injury.

The mechanism of action may be related to the inhibition of TLR4 and the enhancement of the Nrf2 signaling pathway.