MicroRNA-181b Inhibits Inflammatory Response and Reduces Myocardial Injury in Sepsis by Downregulating HMGB1

Biliary HMGB1 levels and biochemical indices in the assessment of acute obstructive septic cholangitis combined with septic shock

BACKGROUND

Acute Obstructive Septic Cholangitis (AOSC) is a serious infectious disease of the biliary system. It is prone to develop into septic shock without prompt management.

METHODS

Bile was collected from 71 AOSC patients (45 AOSC without septic shock, 26 AOSC with septic shock) during biliary drainage and on days 1 and 3 postoperatively. The levels of High Mobility Group Protein 1 (HMGB1), Interleukin (IL)-1, IL-6, and Tumor Necrosis Factor alpha (TNF-α) were measured. The differences in the levels of biliary factors and their correlation with clinical biochemical indicators were assessed in the two groups.

RESULTS

HMGB1 gradually decreased in both groups in the postoperative period. Intraoperative levels of biliary HMGB1 were significantly higher in patients with AOSC with septic shock. TNF-α and HMGB1 decreased slowly in patients with AOSC with septic shock on postoperative days 1 and 3, and the levels of the factors decreased less. Biliary HMGB1 levels were negatively correlated with white blood cell count and positively correlated with blood urea nitrogen, blood creatinine, procalcitonin, and C-reactive protein. A bile HMGB1 level of 1108.3 pg/mL was the cut-off value to differentiate patients with AOSC with or without septic shock.

CONCLUSION

Biliary HMGB1 levels are elevated in patients with AOSC with septic shock and decrease slowly in the postoperative period. This suggests that HMGB1 is of considerable importance as a potential therapeutic target in the pathogenesis of septic shock in AOSC patients.

MicroRNAs as regulators of cardiac dysfunction in sepsis: pathogenesis and diagnostic potential

Introduction

Sepsis, a life-threatening condition arising from an uncontrolled immune response to infection, can lead to organ dysfunction, with severe inflammation potentially causing multiple organ failures. Sepsis-induced cardiac dysfunction (SIMD) is a common and severe complication of sepsis, significantly increasing patient mortality. Understanding the pathogenesis of SIMD is crucial for improving treatment, and microRNAs (miRNAs) have emerged as important regulators in this process.

Methods

A comprehensive literature search was conducted in PubMed, Science Direct, and Embase databases up to September 2024. The search terms included ["miRNA" or "microRNA"] and ["Cardiac" or "Heart"] and ["Sepsis" or "Septic"], with the language limited to English. After initial filtering by the database search engine, Excel software was used to further screen references. Duplicate articles, those without abstracts or full texts, and review/meta-analyses or non-English articles were excluded. Finally, 106 relevant research articles were included for data extraction and analysis.

Results

The pathogenesis of SIMD is complex and involves mitochondrial dysfunction, oxidative stress, cardiomyocyte apoptosis and pyroptosis, dysregulation of myocardial calcium homeostasis, myocardial inhibitory factors, autonomic nervous regulation disorders, hemodynamic changes, and myocardial structural alterations. miRNAs play diverse roles in SIMD. They are involved in regulating the above-mentioned pathological processes.

Discussion

Although significant progress has been made in understanding the role of miRNAs in SIMD, there are still challenges. Some studies on the pathogenesis of SIMD have limitations such as small sample sizes and failure to account for confounding factors. Research on miRNAs also faces issues like inconsistent measurement techniques and unclear miRNA-target gene relationships. Moreover, the translation of miRNA-based research into clinical applications is hindered by problems related to miRNA stability, delivery mechanisms, off-target effects, and long-term safety. In conclusion, miRNAs play a significant role in the pathogenesis of SIMD and have potential as diagnostic biomarkers. Further research is needed to overcome existing challenges and fully exploit the potential of miRNAs in the diagnosis and treatment of SIMD.

Targeting high-mobility-group-box-1-mediated inflammation: a promising therapeutic approach for myocardial infarction

Myocardial ischemia, resulting from coronary artery blockage, precipitates cardiac arrhythmias, myocardial structural changes, and heart failure. The pathophysiology of MI is mainly based on inflammation and cell death, which are essential in aggravating myocardial ischemia and reperfusion injury. Emerging research highlights the functionality of high mobility group box-1, a non-histone nucleoprotein functioning as a chromosomal stabilizer and inflammatory mediator. HMGB1's release into the extracellular compartment during ischemia acts as damage-associated molecular pattern, triggering immune reaction by pattern recognition receptors and exacerbating tissue inflammation. Its involvement in signaling pathways like PI3K/Akt, TLR4/NF-κB, and RAGE/HMGB1 underscores its significance in promoting angiogenesis, apoptosis, and reducing inflammation, which is crucial for MI treatment strategies. This review highlights the complex function of HMGB1 in the pathogenesis of myocardial infarction by summarizing novel findings on the protein in ischemic situations. Understanding the mechanisms underlying HMGB1 could widen the way to specific treatments that minimize the severity of MI and enhance patient outcomes.

Engineered exosomes: a potential therapeutic strategy for septic cardiomyopathy

Septic cardiomyopathy, a life-threatening complication of sepsis, can cause acute heart failure and carry a high mortality risk. Current treatments have limitations. Fortunately, engineered exosomes, created through bioengineering technology, may represent a potential new treatment method. These exosomes can both diagnose and treat septic cardiomyopathy, playing a crucial role in its development and progression. This article examines the strategies for using engineered exosomes to protect cardiac function and treat septic cardiomyopathy. It covers three innovative aspects: exosome surface modification technology, the use of exosomes as a multifunctional drug delivery platform, and plant exosome-like nanoparticle carriers. The article highlights the ability of exosomes to deliver small molecules, proteins, and drugs, summarizing several RNA molecules, proteins, and drugs beneficial for treating septic cardiomyopathy. Although engineered exosomes are a promising biotherapeutic carrier, they face challenges in clinical application, such as understanding the interaction mechanism with host cells, distribution within the body, metabolism, and long-term safety. Further research is essential, but engineered exosomes hold promise as an effective treatment for septic cardiomyopathy.

IFITM3 overexpression reverses insufficient healing benefits of small extracellular vesicles from high-fat-diet BMSCs in sepsis via the HMGB1 pathway

Bone marrow mesenchymal stem cells (BMSCs) are a promising new therapy for sepsis, a common cause of death in hospitals. However, the global epidemic of metabolic syndromes, including obesity and pre-obesity, threatens the health of the human BMSC pool. The therapeutic effects of BMSCs are primarily due to the secretion of the small extracellular vesicles containing lipids, proteins, and RNA. Accordingly, studies on BMSCs, their small extracellular vesicles, and their modifications in obese individuals are becoming increasingly important. In this study, we investigated the therapeutic potential of small extracellular vesicles (sEVs) from high-fat diet BMSCs (sEVsHFD) in sepsis-induced liver-heart axis injury. We found that sEVsHFD yielded diminished therapeutic benefits compared to sEVs from chow diet BMSCs (sEVsCD). We subsequently verified that IFITM3 significantly differed in sEVsCD and sEVsHFD, alternating in septic liver tissue, and indicating its potential as a remodeling target of sEVs. IFITM3-overexpressed high-fat-diet BMSCs (HFD-BMSCs) showed that corresponding sEVs (sEVsHFD-IFITM3) markedly ameliorated liver-heart axis injury during sepsis. Lastly, we identified the protective action mechanisms of sEVsHFD-IFITM3 in sepsis-induced organ failure and HMGB1 expression and secretion was altered in septic liver and serum while HMGB1 has been demonstrated as a critical mediator of multi-organ failure in sepsis. These findings indicate that IFITM3 overexpression regenerates the therapeutic benefit of sEVs from HFD-BMSCs in sepsis via the HMGB1 pathway.

Identification of PIK3R5 as a hub in septic myocardial injury and the cardioprotective effects of Psoralidin

BACKGROUND

Myocardial injury is a severe complication of sepsis, resulting in substantial morbidity and mortality. Psoralidin (PSO), derived from the seeds of Psoralea corylifolia L., has garnered considerable attention due to its potent pharmacological effects, including anti-inflammatory and antibacterial effects.

PURPOSE

Our previous work conducted affirmed that PSO has a protective effect on sepsis and septic myocardial injury, however the specific molecular mechanisms need further clarification.

STUDY DESIGN

This objective of this study was to use three analytic modalities and bioinformatics methods to identify potential targets, followed by experimental verification.

METHODS

A series of experiments methods (including echocardiography, HE, western blot, qPCR, RNA-seq, network pharmacology) were used to evaluate the effects of PSO against sepsis and septic myocardial injury in cecal ligation and puncture (CLP)-injured BALB/c mice and lipopolysaccharide (LPS)-injured HL-1 cardiomyocytes.

RESULTS

Firstly, a group of sepsis-related genes were identified by integrating database surveys, RNA-seq analysis, and weighted gene co-expression network analysis (WCGNA). Subsequently, the pharmacological targets of PSO were predicted. Furthermore, the identification of phosphoinositide 3- kinase regulatory subunit 5 (PIK3R5) as a crucial hub gene was accomplished via protein-protein interaction network and molecular docking approach. In vivo experiments showed that PSO treatment alleviated septic myocardial injury, as evidenced by improved cardiac function indicators and inflammation response. Similar results were obtained in vitro experiments. Importantly, the expression of PI3KR5 was decreased in the myocardium and cardiomyocytes, and the effect was reversed by PSO treatment.

CONCLUSION

This study systematically revealed the key targets of PSO in the treatment of septic myocardial injury. These findings offer valuable insights into disease-drug targets, which have certain clinical significance to exploring disease biomarkers and potential therapeutic targets for septic patients.

Emerging roles of microRNAs in septic cardiomyopathy

As one of the serious complications of sepsis, septic cardiomyopathy has gained more and more attention, because of its high morbidity and mortality. With the in-depth study of septic cardiomyopathy, several methods have been adopted clinically but have poor therapeutic effects due to failure to find precise therapeutic targets. In recent years, microRNAs have been found to be related to the pathogenesis, diagnosis, and treatment of septic cardiomyopathy via regulating immunity and programmed cell death. This paper reviews the role of microRNAs in septic cardiomyopathy, aiming to provide new targets for the diagnosis and treatment of septic cardiomyopathy.

Silencing long non-coding RNA SNHG3 repairs the dysfunction of pulmonary microvascular endothelial barrier by regulating miR-186-5p/Wnt axis

Barrier permeability changes of human pulmonary microvascular endothelial cells (HPMVECs) are important in sepsis-related acute lung injury (ALI) pathogenesis. Long non-coding small nucleolar RNA host gene 3 (SNHG3) mediates the cell-biological phenotype of lung cancer cells and affects the progression of lung cancer, but its role in regulating functions of lung non-malignant cells is still rarely reported. Therefore, we evaluated the regulatory effect of SNHG3 on the function of PMVECs in sepsis-related ALI. Small interference RNA (siRNA)-mediated deletion of SNHG3 promoted the proliferation of PMVECs, reduced apoptosis and barrier permeability, and increased the expression of tight junction proteins claudin-5 and ZO-1. Knockdown of SNHG3 increased the miR-186-5p expression, while overexpression of SNHG3 upregulated the level of wnt5a. Through a dual luciferase reporter assay, we confirmed the binding between SNHG3 and miR-186-5p, miR-186-5p and wnt5a. We further found that knockout of miR-186-5p could inhibit cell proliferation, increase apoptosis and barrier permeability, and down-regulate claudin-5 and ZO-1. Importantly, silencing miR-186-5p and activating Wnt signal pathway could eliminate the barrier repair effect caused by down-regulation of SNHG3. To sum up, our results suggested that knockdown of long non-coding RNA SNHG3 repaired the dysfunction of pulmonary microvascular endothelial barrier through the miR-186-5p/Wnt axis.

LncRNA ANRIL-mediated miR-181b-5p/S1PR1 axis is involved in the progression of uremic cardiomyopathy through activating T cells

This study aimed to explore the regulatory role of lncRNA ANRIL/miR-181b-5p/S1PR1 in UC. UC mouse model was established by 5/6th nephrectomy. We detected body weight, serum levels of renal function and inflammatory factors (biochemical analyzer/ELISA), and cardiac parameters (echocardiography). HE and Masson staining showed the pathological changes and fibrosis in myocardial and nephridial tissues. The expression of ANRIL, miR-181b-5p, and S1PR1 were detected by qRT-PCR or Western blot/immunofluorescence. T cells activation was analyzed by Flow cytometry. ANRIL/S1PR1 were up-regulated and miR-181b-5p was down-regulated in UC mice. ANRIL silencing up-regulated miR-181b-5p and down-regulated S1PR1 (a target of miR-181b-5p). ANRIL silencing increased the body weight, recovered renal function [decreased blood urea nitrogen (BUN) and serum creatinine (Scr)] and cardiac function [decreased left ventricular end-diastolic diameter (LVEDD), LV end-systolic diameter (LVESD), LV systolic anterior wall thickness (LVAWS), LV end-diastolic anterior wall thickness (LVAWD), myocardial performance index (MPI), and isovolumic relaxation time (IVRT); increased LV ejection fraction (LVEF), LVEF/MPI, fractional shortening (FS), and E- and A-waves (E/A)], inhibited the inflammation [decreased interferon (IFN)-γ, interleukin (IL)-2, IL-10, and tumor necrosis factor (TNF)-α], and relieved pathological injuries and fibrosis. ANRIL silencing also recovered the viability and inhibited the inflammation of activated T cells in vitro, and inhibited T cell activation in UC mice in vivo. In addition, miR-181b-5p overexpression exhibited same effects with ANRIL silencing in UC. ANRIL silencing inhibited T cell activation through regulating miR-181b-5p/S1PR1, contributing to the remission of UC.

Modes of action and diagnostic value of miRNAs in sepsis

Sepsis is a clinical syndrome defined as a dysregulated host response to infection resulting in life-threatening organ dysfunction. Sepsis is a major public health concern associated with one in five deaths worldwide. Sepsis is characterized by unbalanced inflammation and profound and sustained immunosuppression, increasing patient susceptibility to secondary infections and mortality. microRNAs (miRNAs) play a central role in the control of many biological processes, and deregulation of their expression has been linked to the development of oncological, cardiovascular, neurodegenerative and metabolic diseases. In this review, we discuss the role of miRNAs in sepsis pathophysiology. Overall, miRNAs are seen as promising biomarkers, and it has been proposed to develop miRNA-based therapies for sepsis. Yet, the picture is not so straightforward because of the versatile and dynamic features of miRNAs. Clearly, more research is needed to clarify the expression and role of miRNAs in sepsis, and to promote the use of miRNAs for sepsis management.

Research Progress on the Mechanism of Sepsis Induced Myocardial Injury

Sepsis is an abnormal condition with multiple organ dysfunctions caused by the uncontrolled infection response and one of the major diseases that seriously hang over global human health. Besides, sepsis is characterized by high morbidity and mortality, especially in intensive care unit (ICU). Among the numerous subsequent organ injuries of sepsis, myocardial injury is one of the most common complications and the main cause of death in septic patients. To better manage septic inpatients, it is necessary to understand the specific mechanisms of sepsis induced myocardial injury (SIMI). Therefore, this review will elucidate the pathophysiology of SIMI from the following certain mechanisms: apoptosis, mitochondrial damage, autophagy, excessive inflammatory response, oxidative stress and pyroptosis, and outline current therapeutic strategies and potential approaches in SIMI.

High Mobility Group Proteins in Sepsis

Sepsis, a systemic inflammatory response disease, is the most severe complication of infection and a deadly disease. High mobility group proteins (HMGs) are non-histone nuclear proteins binding nucleosomes and regulate chromosome architecture and gene transcription, which act as a potent pro-inflammatory cytokine involved in the delayed endotoxin lethality and systemic inflammatory response. HMGs increase in serum and tissues during infection, especially in sepsis. A growing number of studies have demonstrated HMGs are not only cytokines which can mediate inflammation, but also potential therapeutic targets in sepsis. To reduce sepsis-related mortality, a better understanding of HMGs is essential. In this review, we described the structure and function of HMGs, summarized the definition, epidemiology and pathophysiology of sepsis, and discussed the HMGs-related mechanisms in sepsis from the perspectives of non-coding RNAs (microRNA, long non-coding RNA, circular RNA), programmed cell death (apoptosis, necroptosis and pyroptosis), drugs and other pathophysiological aspects to provide new targets and ideas for the diagnosis and treatment of sepsis.

miR-107 Attenuates Sepsis-Induced Myocardial Injury by Targeting PTEN and Activating the PI3K/AKT Signaling Pathway

Sepsis is a public health problem worldwide. This study investigated the mechanism of miR-107 on sepsis-induced myocardial injury. Sepsis rat models were established by cecal ligation and puncture (CLP), and the cell model was established using lipopolysaccharide (LPS)-induced cardiomyocytes. Cardiac function indexes of rats were measured using echocardiography. Pathological changes in the rat myocardium were observed using histological staining. Expression of miR-107 in the serum of rats and in cardiomyocytes was detected after the treatment with miR-107 mimic and/or pcDNA3.1-PTEN, followed by assessment of cell cycle, proliferation, and apoptosis. Binding sites of miR-107 and PTEN were predicted. PTEN, PI3K, p-PI3K, AKT, and p-AKT levels in LPS-induced cardiomyocytes were measured. miR-107 was significantly downregulated in the serum of CLP rats and LPS-induced cardiomyocytes. miR-107 overexpression remarkably improved cardiac function and histological changes, decreased inflammatory factors, and alleviated the sepsis-induced myocardial injury in rats. In LPS-induced cardiomyocytes, miR-107 overexpression increased cardiomyocyte proliferation, inhibited apoptosis, and enhanced the proportion of cardiomyocytes arrested in S and G2/M phases. miR-107 targeted PTEN. PTEN overexpression partially reversed the inhibition of miR-107 mimic on cardiomyocyte apoptosis. miR-107 overexpression activated the PI3K/AKT pathway by inhibiting PTEN. To conclude, miR-107 activates the PI3K/AKT pathway by inhibiting PTEN, thus attenuating sepsis-induced myocardial injury and LPS-induced cardiomyocyte apoptosis.

miR-181b regulates vascular endothelial aging by modulating an MAP3K3 signaling pathway

Endothelial cell (EC) aging plays a vital role in the pathogenesis of cardiovascular disease (CVD). MicroRNAs have emerged as crucial regulators of target gene expression by inhibiting mRNA translation and/or promoting mRNA degradation. We identify an aging-related and oxidative stress-responsive microRNA, miR-181b, that inhibits endothelial cell apoptosis and senescence. In gain- or loss-of-function studies, miR-181b regulated the expression of key apoptosis markers (Bcl2, Bax, cleaved-Caspase3) and senescence markers (p16, p21, γH2AX) and the ratio of apoptotic cells (TUNEL-positive) and senescent cells (SA-βgal-positive) in H2 O2 -induced ECs. Mechanistically, miR-181b targets MAP3K3 and modulates a MAP3K3/MKK/MAPK signaling pathway. MAP3K3 knockdown recapitulated the phenotype of miR-181b overexpression and miR-181b was dependent on MAP3K3 for regulating EC apoptosis and senescence. In vivo, miR-181b expression showed a negative correlation with increasing age in the mouse aorta. Endothelial-specific deficiency of miR-181a2b2 increased the target MAP3K3, markers of vascular senescence (p16, p21), and DNA double-strand breaks (γH2AX) in the aorta of aged mice. Collectively, this study unveils an important role of miR-181b in regulating vascular endothelial aging via an MAP3K3-MAPK signaling pathway, providing new potential therapeutic targets for antiaging therapy in CVD.

MiR-501-5p alleviates cardiac dysfunction in septic patients through targeting NR4A3 to prevent its binding with Bcl-2

Sepsis-induced myocardial dysfunction is a common complication in septic patients. To date, a limited number of biomarkers that could predict cardiomyocyte apoptosis have been explored. In this study, we successfully established a cecal ligation and puncture (CLP)-induced septic model, and it was found that miR-501-5p expression was down-regulated in peripheral blood samples of septic patients with cardiac dysfunction, lipopolysaccharide (LPS)-induced cardiomyocytes, and the myocardium and peripheral blood in the septic model. Moreover, it was revealed that miR-501-5p overexpression could increase left ventricular diastolic pressure (LVDP), fractional shortening (FS), ejection fraction (EF), and maximum rate of the rise of left ventricular pressure (+dp/dt) in vivo, while it decreased the levels of myocardial injury-related indicators. In addition, LPS induction accelerated apoptosis and elevated the inflammation in HL-1 and HCM cells, which could be reversed by miR-501-5p overexpression. Mechanistically, we considered nuclear receptor subfamily 4 group A member 3 (NR4A3) as the target of miR-501-5p, and it was found that miR-501-5p prevented the binding between NR4A3 and Bcl-2. It was found that miR-501-5p exerted an inhibitory effect on cardiomyocyte apoptosis and inflammation in a NR4A3-dependent manner. Overall, our results may provide evidence for consideration of miR-501-5p in the therapy of sepsis.