Protective effect of trimetazidine in radiation-induced cardiac fibrosis in mice

Fig. 1.. Effects of trimetazidine on myocardial collagen in mice. (A) Masson staining 8 weeks after irradiation showed that collagen fibres increased and invaded into the muscles. The myocardium is indicated in red and collagen is indicated in blue. Magnification 400×. (B) The collagen volume fraction (CVF) in myocardial tissue was calculated. As shown in (A), the proportion of collagen fibre in the heart of the radiation-only group was significantly higher than those of the other groups. The analysis found no significant difference between the experimental groups LDPre and LDPost (cP > 0.05) or HDPre and HDPost (dP > 0.05), but there were significant differences between experimental groups LDPre and HDPre (cP < 0.05) and between LDPost and HDPost (eP < 0.05).

Fig. 2.. CTGF expression in the mouse heart. (A) Immunohistochemistry was performed 8 weeks after irradiation to reveal the effect of trimetazidine on the changes in CTGF in mice. Magnification 400×. (B) Comparison of the positive expression rates of CTGF protein in the myocardial tissues of each group. (C) Quantitative analysis of the transcriptional expression of CTGF by qRT-PCR. The CTGF levels in the mouse hearts of the other groups were lower than those of the Mod group (bP < 0.05). The low-dose groups and high-dose groups displayed significant differences (cP < 0.05, dP < 0.05). The analysis found no significant difference between groups LDPre and LDPost (cP > 0.05), and there was no significant difference between groups HDPre and HDPost (dP > 0.05).

Fig. 3.. TGF-β1 expression in the mouse heart. (A) Immunohistochemistry was performed 8 weeks after irradiation to reveal the effect of trimetazidine on changes in TGF-β1 in mice. Magnification 400×. (B) Comparison of the positive expression rates for TGF-β1 protein in the myocardial tissues of each group. (C) Quantitative analysis of the transcriptional expression of TGF-β1 by qRT-PCR. The TGF-β1 levels in the mouse hearts of the other groups were lower than those of the Mod group (bP < 0.05). The low-dose groups and high-dose groups showed significant differences (cP < 0.05, dP < 0.05). The analysis found no significant difference between groups LDPre and LDPost (cP > 0.05) or between groups HDPre and HDPost (dP > 0.05).

Fig. 4.. Smad2 expression in the mouse heart. (A) Immunohistochemistry was performed 8 weeks after irradiation to reveal the effect of trimetazidine on the changes in Smad2 in mice. Magnification 400×. (B) Comparison of the positive expression rates for Smad2 protein in the myocardial tissues of each group. (C) Quantitative analysis of the transcriptional expression of Smad2 by qRT-PCR. The Smad2 levels in the mouse hearts of the other groups were lower than those of the Mod group (bP < 0.05). The low-dose groups and high-dose groups showed significant differences (cP < 0.05, dP < 0.05). The analysis found no significant difference between groups LDPre and LDPost (cP > 0.05) or between groups HDPre and HDPost (dP > 0.05).

Fig. 5.. Smad3 expression in the mouse heart. (A) Immunohistochemistry was performed 8 weeks after irradiation to reveal the effect of trimetazidine on the changes in Smad3 in mice. Magnification 400×. (B) Comparison of the positive expression rates of Smad3 protein in the myocardial tissues of each group. (C) Quantitative analysis of the transcriptional expression of Smad3 by qRT-PCR. The Smad3 levels in the mouse hearts of the other groups were lower than those of the Mod group (bP < 0.05). The low-dose groups and high-dose groups showed significant differences (cP < 0.05, dP < 0.05). The analysis found no significant difference between groups LDPre and LDPost (cP > 0.05) or between groups HDPre and HDPost (dP > 0.05).