Suxiao Jiuxin Pill alleviates myocardial ischemia/reperfusion-induced autophagy via miR-193a-3p/ALKBH5 pathway.

BACKGROUND: Myocardial ischemia/reperfusion injury (MIRI) poses a formidable challenge to cardiac reperfusion therapy due to the absence of effective clinical interventions. Methylation of N6-methyladenosine (m6A), which is the most common post-transcriptional modifications occurring within mammalian mRNA, is believed to be involved in MIRI by modulating autophagy. MicroRNAs (miRNAs) play a crucial role in regulating gene expression at the post-transcriptional level and have been implicated in the regulation of m6A methylation. Suxiao Jiuxin Pill (SJP) is extensively used in China for the clinical treatment of angina pectoris and confers benefits to patients with acute coronary syndrome who have received percutaneous coronary intervention. However, the precise mechanisms underlying SJP intervention in MIRI remain unclear. PURPOSE: This study aimed to demonstrate, both in vivo and in vitro, that SJP could alleviate autophagy in MIRI by regulating miR-193a-3p to target and upregulate the demethylase ALKBH5. METHODS: An in vitro hypoxia/reoxygenation model was established using H9c2 cells, while an in vivo MIRI model was established using Wistar rats. A lentivirus harboring the precursor sequence of miR-193a-3p was employed for its overexpression. Adeno-associated viruses were used to silence both miR-193a-3p and ALKBH5 expressions. Cardiac function, infarct size, and tissue structure in rats were assessed using echocardiography, triphenyl tetrazolium chloride (TTC) staining, and HE staining, respectively. Terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) was employed to detect the levels of apoptosis in rat cardiac tissue. m6A methylation levels were assessed using colorimetry. GFP-RFP-LC3B was used to monitor autophagic flux and transmission electron microscopy was used to evaluate the development of autophagosomes. Western Blot and qRT-PCR were respectively employed to assess the levels of autophagy-related proteins and miR-193a-3p. RESULTS: SJP alleviated autophagy, preserved cardiac function, and minimized myocardial damage in the hearts of MIRI rats. SJP attenuated autophagy in H/R H9C2 cells. Elevated levels of miR-193a-3p were observed in the cardiac tissues of MIRI rats and H/R H9C2 cells, whereas SJP downregulated miR-193a-3p levels in these models. ALKBH5, a target gene of miR-193, is negatively regulated by miR-193a-3p. Upon overexpression of miR-193a-3p or silencing of ALKBH5, m6A methylation decreased, and the autophagy-attenuating effects of SJP and its components, senkyunolide A and l-borneol, were lost in H/R H9C2 cells, whereas in MIRI rats, these effects were not abolished but merely weakened. Further investigation indicated that the METTL3 inhibitor STM2475, combined with the silencing of miR-193a-3p, similarly attenuated autophagy in the hearts of MIRI rats. This suggests that a reduction in m6A methylation is involved in autophagy alleviation. CONCLUSION: We demonstrated that SJP mitigates autophagy in MIRI by downregulating miR-193a-3p, enhancing ALKBH5 expression, and reducing m6A methylation, a mechanism potentially attributed to its constituents, senkyunolide A and l-borneol.

Plasma Metabolic Profiling and Multiclass Diagnostic Model Development for Stable Angina Pectoris and Acute Myocardial Infarction.

Coronary heart disease remains a major global health challenge, with a clear need for enhanced early risk assessment. This study aimed to elucidate metabolic signatures across various stages of coronary heart disease and develop an effective multiclass diagnostic model. Using metabolomic approaches, gas chromatography-mass and liquid chromatography-tandem mass spectrometry were used to analyze plasma samples from healthy controls, patients with stable angina pectoris, and those with acute myocardial infarction. Pathway enrichment analysis was conducted on metabolites exhibiting significant differences. The key metabolites were identified using Random Forest and Recursive Feature Elimination strategies to construct a multiclass diagnostic model. The performance of the model was validated through 10-fold cross-validation and evaluated using confusion matrices, receiver operating characteristic curves, and calibration curves. Metabolomics was used to identify 1491 metabolites, with 216, 567, and 295 distinctly present among the healthy controls, patients with stable angina pectoris, and those with acute myocardial infarction, respectively. This implicated pathways such as the glucagon signaling pathway, d-amino acid metabolism, pyruvate metabolism, and amoebiasis across various stages of coronary heart disease. After selection, testosterone isobutyrate, N-acetyl-tryptophan, d-fructose, l-glutamic acid, erythritol, and gluconic acid were identified as core metabolites in the multiclass diagnostic model. Evaluating the diagnostic model demonstrated its high discriminative ability and accuracy. This study revealed metabolic pathway perturbations at different stages of coronary heart disease, and a precise multiclass diagnostic model was established based on these findings. This study provides new insights and tools for the early diagnosis and treatment of coronary heart disease.