Involvement of HIF1α/Reg protein in the regulation of HMGB3 in myocardial infarction

Hsa_circ_0004662 Accelerates the Progression of Ulcerative Colitis via the microRNA-532/HMGB3 Signalling Axis

Increasing research has indicated that circular RNAs (circRNAs) are crucial for the development of ulcerative colitis (UC). Thus, we attempted to identify the role of hsa_circ_0004662 in UC progression. Hsa_circ_0004662 expression was determined via qRT-PCR. Lipopolysaccharide (LPS)-induced inflammation in normal colonic epithelial cells (ECs). The hsa_circ_0004662 content was then assessed in a mucosal inflammatory bowel disease (IBD) model. Cell proliferation was examined via CCK-8 and EdU uptake assays. Apoptotic rates were analysed via flow cytometry. The protein content was quantified via Western blotting. Enzyme-linked immunosorbent assay kits were used to detect IL-1β, TNF-α and IL-6, and dual-luciferase reporter (DLR) assays were used to identify interactions between miR-532 and circ_0004662 or HMGB3. An animal model of UC was also developed for confirmation. In this study, we identified the function of hsa_circ_0004662 in promoting UC progression. Hsa_circ_0004662 was upregulated in clinical UC tissues and LPS-induced colonic ECs, and its knockdown inhibited apoptosis, reduced inflammatory cytokine release and promoted cell proliferation in vitro. Mechanistically, hsa_circ_0004662 acted as a molecular sponge for miR-532, which targets HMGB3. The hsa_circ_0004662/miR-532/HMGB3 axis was further validated in a DSS-induced colitis mouse model, where hsa_circ_0004662 knockdown attenuated inflammation and tissue damage. These findings suggested that hsa_circ_0004662 contributes to UC progression through the miR-532/HMGB3 signalling pathway, offering potential targets for UC therapy.

Exploring the mechanism of pachymic acid intervention in myocardial ischemia based on network pharmacology and experimental validation

OBJECTIVES

To deeply explore the mechanism of pachymic acid (PA) intervention in myocardial ischemia, providing new ideas and methods for the treatment of myocardial ischemia.

METHODS

Predict the targets of PA for improving myocardial ischemia, and conduct functional enrichment analysis using databases, such as Gene Ontology, Kyoto Encyclopedia of Genes and Genomes, and Reactome. To verify these findings, PPI network topology analysis and molecular docking were used to screen key targets and main mechanisms of action and further validated through in vitro experiments on the H9C2 cell line.

KEY FINDINGS

PA can significantly alleviate myocardial damage caused by hypoxia/reoxygenation, effectively reversing the abnormalities of oxidative stress indicators such as LDH, MDA, SOD, and ROS. PA may exert its effects through 39 targets, particularly by regulating the downregulation of autophagy-related proteins LC3-II and Beclin-1 expression via MTOR, thereby inhibiting excessive autophagy in cardiomyocytes.

CONCLUSIONS

PA protects myocardial cells during myocardial ischemia through various pathways, particularly by regulating mTOR to inhibit excessive autophagy.

Controversial Roles of Regenerating Family Proteins in Tissue Repair and Tumor Development

Background: Over the past 40 years since the discovery of regenerating family proteins (Reg proteins), numerous studies have highlighted their biological functions in promoting cell proliferation and resisting cell apoptosis, particularly in the regeneration and repair of pancreatic islets and exocrine glands. Successively, short peptides derived from Reg3δ and Reg3α have been employed in clinical trials, showing favorable therapeutic effects in patients with type I and type II diabetes. However, continued reports have been limited, presumably attributed to the potential side effects. Methods: This review summarizes extensive research on Reg proteins over the past decade, combined with our own related studies, proposing that Reg proteins exhibit dimorphic effects. Results: The activity of Reg proteins is not as simplistic as previously perceived but shows auto-immunogenicity depending on different pathophysiological microenvironments. The immunogenicity of Reg proteins could recruit immune cells leading to an anti-tumor effect. Such functional diversity is correlated with their structural characteristics: the N-terminal region contributes to autoantigenicity, while the C-type lectin fragment near the C-terminal determines the trophic action. It should be noted that B-cell masking antigens might also reside within the C-type lectin domain. Conclusions: Reg proteins have dual functional roles under various physiological and pathological conditions. These theoretical foundations facilitate the subsequent development of diagnostic reagents and therapeutic drugs targeting Reg proteins.

Structure and Functions of HMGB3 Protein

HMGB3 protein belongs to the group of HMGB proteins from the superfamily of nuclear proteins with high electrophoretic mobility. HMGB proteins play an active part in almost all cellular processes associated with DNA-repair, replication, recombination, and transcription-and, additionally, can act as cytokines during infectious processes, inflammatory responses, and injuries. Although the structure and functions of HMGB1 and HMGB2 proteins have been intensively studied for decades, very little attention has been paid to HMGB3 until recently. In this review, we summarize the currently available data on the molecular structure, post-translational modifications, and biological functions of HMGB3, as well as the possible role of the ubiquitin-proteasome system-dependent HMGB3 degradation in tumor development.

The Role of Pro-Opiomelanocortin Derivatives in the Development of Type 2 Diabetes-Associated Myocardial Infarction: Possible Links with Prediabetes

Myocardial infarction is a major contributor to CVD-related mortality. T2DM is a risk factor for MI. Stress activates the HPA axis, SNS, and endogenous OPS. These POMC derivatives increase the blood glucose and cardiovascular response by inhibiting the PI3K/AkT insulin signaling pathway and increasing cardiac contraction. Opioids regulate the effect of the HPA axis and SNS and they are cardioprotective. The chronic activation of the stress response may lead to insulin resistance, cardiac dysfunction, and MI. Stress and T2DM, therefore, increase the risk of MI. T2DM is preceded by prediabetes. Studies have shown that prediabetes is associated with an increased risk of MI because of inflammation, hyperlipidemia, endothelial dysfunction, and hypertension. The HPA axis is reported to be dysregulated in prediabetes. However, the SNS and the OPS have not been explored during prediabetes. The effect of prediabetes on POMC derivatives has yet to be fully explored and understood. The impact of stress and prediabetes on the cardiovascular response needs to be investigated. This study sought to review the potential impact of prediabetes on the POMC derivatives and pathways that could lead to MI.