4-hydroxysesamin protects rat with right ventricular failure due to pulmonary hypertension by inhibiting JNK/p38 MAPK signaling

Abstract

The specific mechanism of 4-hydroxysesamin (4-HS), a modification of Sesamin, on right ventricular failure due to pulmonary hypertension (PH) is ominous. By creating a rat model of PH in vivo and a model of pulmonary artery smooth muscle cell (PASMC) hypoxia and inflammation in vitro, the current work aimed to investigate in depth the molecular mechanism of the protective effect of 4-HS. In an in vitro model of hypoxia PASMC, changes in cell proliferation and inflammatory factors were detected after treatment with 4-HS, followed by changes in the JNK/p38 MAPK signaling pathway as detected by Western blot signaling pathway. The findings demonstrated that 4-HS was able to minimize PASMC cell death, block the JNK/p38 MAPK signaling pathway, and resist the promoting effect of hypoxia on PASMC cell proliferation. Following that, we found that 4-HS could both mitigate the right ventricular damage brought on by MCT and had a protective impact on rats Monocrotaline (MCT)-induced PH in in vivo investigations. The key finding of this study is that 4-HS may protect against PH by inhibiting the JNK/p38 MAPK signaling pathway.

Keywords: 4-hydroxysesamin; JNK/p38 MAPK signaling pathway; pulmonary hypertension; right ventricular failure.

Figure 1

Effect of Sesamin and 4-HS on the inflammatory response to PASMC cell viability. (A) 2D and 3D molecular structural formulae of 4-HS and the relative molecular mass of 4-HS. (B) CCK8 assay to detect the effect of different concentrations of 4-HS on cellular value-added after acting on PASMC for 24 h. (C) CCK8 assay to detect the effect of 4-HS on the cell viability of PASMC in inflammatory and hypoxic environments. (D) ELISA assay to detect changes in expression of inflammatory factors IL-1β, IL-6, IL-10, and TNF-α in inflammatory and hypoxic environments under 4-HS expression changes of inflammatory factors IL-1β, IL-6, IL-10, and TNF-α after 24 h of 4-HS treatment.

Figure 2

4-HS protects PASMC in inflammatory stimuli and hypoxic environments. (A) EDU staining to detect changes in the proliferative capacity of treated PASMC (Scale bar, 50 μm). (B) CCK8 assay to detect changes in the proliferative capacity of PASMC after treatment with 4-HS PASMC treated with 4-HS and Anisomycin for 24 h. (C) ELISA assay to detect changes in the expression of inflammatory factors IL-1β, IL-6, IL-10, and TNF-α in PASMC treated with 4-HS in combination with Anisomycin for 24 h in LPS and hypoxia-stimulated environments.

Figure 3

4-HS expression of JNK/MANK signaling pathway and proliferation-related proteins. (A) Western blot assay to detect the changes in the expression of JNK, p-JNK, p38 MAPK, and p-p38MAPK proteins in PASMC after treatment. (B) Western blot assay to detect the changes in the expression of CDK2, CyclinD1, and PCNA proteins in PASMC after treatment.

Figure 4

Protective effect of 4-HS on cardiopulmonary function in PH rats. (A) Flowchart of modeling and processing of PH rats. (B) Flowchart of body weight changes of rats in each experimental group from the beginning of PH modeling to the end of modeling, and body weight changes of rats were recorded every 6 days. (C) Detection of changes in systolic pressure of the right ventricle in each experimental group after the end of modeling of PH rats. (D) Detection of changes in Fulton Index in each experimental group. (E) Detection of changes in expression of respiratory rate in each experimental group. (F) Echocardiography measurement of pulmonary artery (PA) function showing normalization of pulmonary acceleration time (PAT). Changes in the expression of respiratory rate. (F) Echocardiography measurement of pulmonary artery (PA) function showing normalization of pulmonary acceleration time (PAT)/pulmonary ejection time (PET) ratio. (G) Detection of changes in EF, FS, LVVs, LVVd, LVIDs, and LVIDd in MCT-induced PH rats after 4-HS treatment.

Figure 5

Protective effect of 4-HS on right ventricular tissue in PH rats. (A) TUNEL staining to detect the effect of 4-HS pretreatment on apoptosis in right ventricular myocardial tissue (Scale bar, 50 μm). (B) Sirius scarlet staining to detect the effect of 4-HS pretreatment on right ventricular myocardial tissue (Scale bar, 50 μm). Effect of fibrosis. (C) ELISA assay to detect changes in the expression of inflammatory factors IL-1β, IL-6, IL-10, and TNF-α in the serum of rats in each group of the experiment. (D) Western blot assay to detect changes in the expression of JNK, p-JNK, p38 MAPK, and p-p38 MAPK proteins in the tissues of pulmonary arteries in rats. (E) Western blot assay to detect changes in the expression of CDK2, CyclinD1, and PCNA proteins in the tissues of pulmonary arteries in rats.