Annexin A1 Mimetic Peptide AC2-26 Inhibits Sepsis-induced Cardiomyocyte Apoptosis through LXA4/PI3K/AKT Signaling Pathway

ANXA1-FPR2 axis mitigates the susceptibility to atrial fibrillation in obesity via rescuing AMPK activity in response to lipid overload

Atrial fibrillation (AF) is the most prevalent arrhythmia in clinical practice, and obesity serves as a significant risk factor for its development. The underlying mechanisms of obesity-related AF remain intricate and have yet to be fully elucidated. We have identified FPR2 as a potential hub gene involved in obesity-related AF through comprehensive analysis of four transcriptome datasets from AF patients and one transcriptome dataset from obese individuals, and its expression is up-regulated in both AF and obese individuals. Interestingly, ANXA1, the endogenous ligand of FPR2, was found to exhibit differential expression with AF and obesity. Specifically, it was observed to be down-regulated in AF patients but up-regulated in obese individuals. The susceptibility to AF in obese mice induced by high-fat diet (HFD) was increased following with the FPR2 blocker Boc-2.The administration of exogenous ANXA1 active peptide chain Ac2-26 can mitigate the susceptibility to AF in obese mice by attenuating atrial fibrosis, lipid deposition, oxidative stress injury, and myocardial cell apoptosis. However, this protective effect against AF susceptibility is reversed by AAV9-shAMPK-mediated AMPK specific knockdown in the myocardium. The vitro experiments demonstrated that silencing ANXA1 exacerbated lipid deposition, oxidative stress injury, and apoptosis induced by palmitic acid (PA) in cardiomyocytes. Additionally, Ac2-26 effectively mitigated myocardial lipid deposition, oxidative stress injury, and apoptosis induced by PA. These effects were impeded by FPR2 inhibitors Boc-2 and WRW4. The main mechanism involves the activation of AMPK by ANXA1 through FPR2 in order to enhance fatty acid oxidation in cardiomyocytes, thereby ultimately leading to a reduction in lipid accumulation and associated lipotoxicity. Our findings demonstrate that the ANXA1-FPR2 axis plays a protective role in obesity-associated AF by alleviating metabolic stress in the atria of obese mice, thereby emphasizing its potential as a promising therapeutic target for AF.

Upregulation of CRISP3 and its clinical values in adult sepsis: a comprehensive analysis based on microarrays and a two-retrospective-cohort study

Background

Current lines of evidence indicate that cysteine-rich secretory protein 3 (CRISP3) is an immunoregulatory factor. Nevertheless, no study has explored the relationships between the values of CRISP3 and sepsis.

Methods

We conducted a comprehensive literature search and meta-analysis from the Gene Expression Omnibus (GEO) and ArrayExpress to determine the expression of CRISP3 in sepsis patients. Then, we explored whether plasma CRISP3 could serve as a potential biomarker to predict the risk of sepsis via two retrospective trauma cohorts. We evaluated the prediction power using the area under the curve (AUC).

Results

A total of 23 datasets were recruited for the comprehensive meta-analysis, and the combined standardized mean difference (SMD) of CRISP3 was 0.90 (0.50-1.30) (p < 0.001), suggesting that CRISP3 was overexpressed in sepsis patients. Meanwhile, sepsis patients had higher CRISP3 concentrations than non-sepsis patients in 54 trauma patients (p < 0.001). Plasma CRISP3 on admission was significantly associated with the incidence of sepsis [OR = 1.004 (1.002-1.006), p < 0.001]. As a predictive biomarker, CRISP3 obtained a better AUC [0.811 (0.681-0.905)] than C-reactive protein (CRP) [0.605 (0.463-0.735)], procalcitonin (PCT) [0.554 (0.412-0.689)], and Sequential Organ Failure Assessment (SOFA) [0.754 (0.618-0.861)]. Additionally, the clinical relationships between plasma CRISP3 and sepsis were verified in another trauma cohort with 166 patients [OR = 1.002 (1.001-1.003), p < 0.001]. The AUC of CRISP3 was 0.772 (0.701-0.834), which was better than that of CRP [0.521 (0.442-0.599)] and PCT [0.531 (0.452-0.609)], but not SOFA [0.791 (0.717-0.853)].

Conclusion

Our study indicated and validated that CRISP3 was highly expressed in sepsis. More importantly, CRISP3 may serve as a latent biomarker to predict the risk of sepsis.

Targeting lipid droplets and lipid droplet-associated proteins: a new perspective on natural compounds against metabolic diseases

BACKGROUND

Lipid droplet (LD) is a metabolically active organelle, which changes dynamically with the metabolic state and energy requirements of cells. Proteins that either insert into the LD phospholipid monolayer or are present in the cytoplasm, playing a crucial role in lipid homeostasis and signaling regulation, are known as LD-associated proteins.

METHODS

The keywords "lipid droplets" and "metabolic diseases" were used to obtain literature on LD metabolism and pathological mechanism. After searching databases including Scopus, OVID, Web of Science, and PubMed from 2013 to 2024 using terms like "lipid droplets", "lipid droplet-associated proteins", "fatty liver disease", "diabetes", "diabetic kidney disease", "obesity", "atherosclerosis", "hyperlipidemia", "natural drug monomers" and "natural compounds", the most common natural compounds were identified in about 954 articles. Eventually, a total of 91 studies of 10 natural compounds reporting in vitro or in vivo studies were refined and summarized.

RESULTS

The most frequently used natural compounds include Berberine, Mangostin, Capsaicin, Caffeine, Genistein, Epigallocatechin-3-gallate, Chlorogenic acid, Betaine, Ginsenoside, Resveratrol. These natural compounds interact with LD-associated proteins and help ameliorate abnormal LDs in various metabolic diseases.

CONCLUSION

Natural compounds involved in the regulation of LDs and LD-associated proteins hold promise for treating metabolic diseases. Further research into these interactions may lead to new therapeutic applications.

Annexin A1 (Ac2-26)-dependent Fpr2 receptor alleviates sepsis-induced acute kidney injury by inhibiting inflammation and apoptosis in vivo and in vitro

OBJECTIVES

Excessive inflammatory responses and apoptosis are critical pathologies that contribute to sepsis-induced acute kidney injury (SI-AKI). Annexin A1 (ANXA1), a member of the calcium-dependent phospholipid-binding protein family, protects against SI-AKI through its anti-inflammatory and antiapoptotic effects, but the underlying mechanisms are still largely unknown.

METHODS

In vivo, SI-AKI mouse models were established via caecal ligation and puncture (CLP) and were then treated with the Ac2-26 peptide of ANXA1 (ANXA1 (Ac2-26)), WRW4 (Fpr2 antagonist) or both. In vitro, HK-2 cells were induced by lipopolysaccharide (LPS) and then treated with ANXA1 (Ac2-26), Fpr2-siRNA or both.

RESULTS

In the present study, we found that the expression levels of ANXA1 were decreased, and the expression levels of TNF-α, IL-1β, IL-6, cleaved caspase-3, cleaved caspase-8 and Bax were significantly increased, accompanied by marked kidney tissue apoptosis in vivo. Moreover, we observed that ANXA1 (Ac2-26) significantly reduced the levels of TNF-α, IL-1β and IL-6 and cleaved caspase-3, cleaved caspase-8, FADD and Bax and inhibited apoptosis in kidney tissue and HK-2 cells, accompanied by pathological damage to kidney tissue. Seven-day survival, kidney function and cell viability were significantly improved in vivo and in vitro, respectively. Furthermore, the administration of ANXA1 (Ac2-26) inhibited the CLP- or LPS-induced phosphorylation of PI3K and AKT and downregulated the level of NF-κB in vivo and in vitro. Moreover, our data demonstrate that blocking the Fpr2 receptor by the administration of WRW4 or Fpr2-siRNA reversed the abovementioned regulatory role of ANXA1, accompanied by enhanced phosphorylation of PI3K and AKT and upregulation of the level of NF-κB in vivo and in vitro.

CONCLUSIONS

Taken together, this study provides evidence that the protective effect of ANXA1 (Ac2-26) on SI-AKI largely depends on the negative regulation of inflammation and apoptosis via the Fpr2 receptor.

Therapeutic Potential of Annexin A1 Modulation in Kidney and Cardiovascular Disorders

Renal and cardiovascular disorders are very prevalent and associated with significant morbidity and mortality. Among diverse pathogenic mechanisms, the dysregulation of immune and inflammatory responses plays an essential role in such disorders. Consequently, the discovery of Annexin A1, as a glucocorticoid-inducible anti-inflammatory protein, has fueled investigation of its role in renal and cardiovascular pathologies. Indeed, with respect to the kidney, its role has been examined in diverse renal pathologies, including acute kidney injury, diabetic nephropathy, immune-mediated nephropathy, drug-induced kidney injury, kidney stone formation, and renal cancer. Regarding the cardiovascular system, major areas of investigation include the role of Annexin A1 in vascular abnormalities, atherosclerosis, and myocardial infarction. Thus, this review briefly describes major structural and functional features of Annexin A1 followed by a review of its role in pathologies of the kidney and the cardiovascular system, as well as the therapeutic potential of its modulation for such disorders.

Molecular mechanism and therapeutic targeting of necrosis, apoptosis, pyroptosis, and autophagy in cardiovascular disease

ABSTRACT

Cell death occurs in various tissues and organs in the body. It is a physiological or pathological process that has different effects. It is of great significance in maintaining the morphological function of cells and clearing abnormal cells. Pyroptosis, apoptosis, and necrosis are all modes of cell death that have been studied extensively by many experts and scholars, including studies on their effects on the liver, kidney, the heart, other organs, and even the whole body. The heart, as the most important organ of the body, should be a particular focus. This review summarizes the mechanisms underlying the various cell death modes and the relationship between the various mechanisms and heart diseases. The current research status for heart therapy is discussed from the perspective of pathogenesis.

Therapeutic Potential of Annexins in Sepsis and COVID-19

Sepsis is a continuing problem in modern healthcare, with a relatively high prevalence, and a significant mortality rate worldwide. Currently, no specific anti-sepsis treatment exists despite decades of research on developing potential therapies. Annexins are molecules that show efficacy in preclinical models of sepsis but have not been investigated as a potential therapy in patients with sepsis. Human annexins play important roles in cell membrane dynamics, as well as mediation of systemic effects. Most notably, annexins are highly involved in anti-inflammatory processes, adaptive immunity, modulation of coagulation and fibrinolysis, as well as protective shielding of cells from phagocytosis. These discoveries led to the development of analogous peptides which mimic their physiological function, and investigation into the potential of using the annexins and their analogous peptides as therapeutic agents in conditions where inflammation and coagulation play a large role in the pathophysiology. In numerous studies, treatment with recombinant human annexins and annexin analogue peptides have consistently found positive outcomes in animal models of sepsis, myocardial infarction, and ischemia reperfusion injury. Annexins A1 and A5 improve organ function and reduce mortality in animal sepsis models, inhibit inflammatory processes, reduce inflammatory mediator release, and protect against ischemic injury. The mechanisms of action and demonstrated efficacy of annexins in animal models support development of annexins and their analogues for the treatment of sepsis. The effects of annexin A5 on inflammation and platelet activation may be particularly beneficial in disease caused by SARS-CoV-2 infection. Safety and efficacy of recombinant human annexin A5 are currently being studied in clinical trials in sepsis and severe COVID-19 patients.

Molecular pathways in sepsis-induced cardiomyocyte pyroptosis: Novel finding on long non-coding RNA ZFAS1/miR-138-5p/SESN2 axis

OBJECTIVE

ZNFX1 antisense RNA1 (ZFAS1) has been emerged as a tumor oncogene or suppressor. However, understanding the biological role and underlying molecular mechanism of ZFAS1 in sepsis induced myocardial injury (SIMI) requires more evidence. This study was assigned to probe the effect of lncRNA ZFAS1 on sepsis-induced pyroptosis in cardiomyocytes and its underlying mechanism.

METHODS

Serums of 22 patients with sepsis-induced myocardial injury (SIMI) and 24 healthy controls were collected to determine the expression levels of ZFAS1 and miR-138-5p. Cardiomyocytes (H9C2) or rats were treated by lipopolysaccharide (LPS) to establish in vivo and in vitro sepsis models. H&E staining was applied to observe myocardial injury of rats. The interactions between ZFAS1 and miR-138-5p as well as miR-138-5p and SESN2 were determined by dual-luciferase reporter gene assay and RNA pull-down assay. TUNEL staining was applied to inspect apoptosis level and CCK-8 to measure cell viability. The mRNA levels of ZFAS1, miR-138-5p and SESN2 were measured by qRT-PCR, while the protein expressions of SESN2 and pyroptosis-related proteins (Caspase-1, ASC and NLRP3) were assessed by Western blotting. Levels of inflammatory factors (TNF-α, IL-1β, IL-6 and IL-18) were evaluated by ELISA.

RESULTS

Patients with SIMI had suppressed ZFAS1 and increased miR-138-5p expression when compared with those in healthy controls. LPS treatment in rats triggered myocardial injury accompanied by interstitial edema and moderate inflammatory cell infiltration. Besides, LPS caused elevated cell apoptosis rate and enhanced cell pyroptosis and inflammation in sepsis cell models. However, ZFAS1 overexpression or SESN2 overexpression in LPS induced rats and in H9C2 cells had meliorated myocardial injury and inflammatory response, indicating that ZFAS1 and SESN2 can inhibit sepsis-induced pyroptosis of cardiomyocytes. MiR-138-5p is a target gene of ZFAS1, while miR-138-5p can negatively mediate SESN2. ZFAS1 alleviated sepsis induced cardiomyocyte pyroptosis by exerting competing endogenous RNA (ceRNA) function to indirectly regulate SESN2, which evidenced by loss and gain functions of ZFAS1 and SESN2.

CONCLUSION

LncRNA ZFAS1 serves as a ceRNA of miR-138-5p to up-regulate the expression of SESN2, thereby ameliorating sepsis-induced cardiomyocyte pyroptosis.

MicroRNA-144-3p enhances LPS induced septic acute lung injury in mice through downregulating Caveolin-2

OBJECTIVE

The emphasis of this study focused on the possible implication and the mechanism of miR-144-3p in septic acute lung injury (ALI) condition.

METHODS

Mice were pre-injected with miR-144-3p agomir, miR-144-3p antagomir, sh-Caveolin-2 or PBS before 10 mg/kg LPS induced sepsis model establishment. The ratio of wet weight of lung tissues and body weight (W/W) was calculated. The pathological changes on lung tissues were observed by H&E staining. Secretions of inflammatory cytokines (TNF-α, IL-1β and IL-6) in both mouse serum and lung tissues were determined by ELISA. Cell apoptosis and cell morphology were measured by TUNEL staining and H&E staining. The expressions of miR-144-3p, Caveolin-2, apoptotic related proteins and JAK/STAT pathway related proteins were measured by qRT-PCR or/and Western blot. Dual luciferase reporter assay was applied to detect the binding of miR-144-3p with Caveolin-2.

RESULTS

LPS resulted in increased W/W, disrupted lung tissue, enhanced inflammatory response and cell apoptosis. miR-144-3p was upregulated while Caveolin-2 was downregulated in response to LPS treatment. Inflammation and cell apoptosis induced by LPS can be alleviated by miR-144-3p antagomir injection, but enhanced by miR-144-3p agomir or sh-Caveolin-2 treatment. miR-144-3p can negatively target Caveolin-2. miR-144-3p can activate the JAK/STAT signal pathway through Caveolin-2 in septic ALI mouse.

CONCLUSION

miR-144-3 can promote LPS induced septic ALI through downregulating Caveolin-2 to activate the JAK/STAT signal pathway.

Ac2-26 mimetic peptide of annexin A1 to treat severe COVID-19: A hypothesis

The Coronavirus Diseases-2019 (COVID-19) pandemic leads many researchers around the world to study the SARS-CoV-s2 infection and pathology to find a treatment for it. This generates a massive production of papers including pre-clinical, clinical and revisions but till now no specific treatment were identified. Meanwhile, like other coronavirus infections, COVID-19 leads to the cytokine storm syndrome resulting in hyperinflammation, exacerbated immune response and multiple organ dysfunctions indicating that drugs that modulate this response, as glucocorticoids could be a treatment option. However glucocorticoids have several side effects or usage limitations. In this sense a drug with anti-inflammatory effects and capable to reduce inflammation but with less after-effects could be a powerful tool to combat COVID-19. Thus the Ac2-26 Mimetic Peptide of Annexin A1 emerges as a possible therapy. The peptide has many anti-inflammatory effects described including the reduction of interleukin (IL)-6, one of the main mediators of cytokine storm syndrome. Therefore the hypothesis to use the Ac2-26 peptide to treat severe COVID-19 will be highlighted in this paper.

GFI-1 Protects Against Lipopolysaccharide-Induced Inflammatory Responses and Apoptosis by Inhibition of the NF-κB/TNF-α Pathway in H9c2 Cells

Growth factor independence 1 (Gfi-1) has been widely studied for its anti-inflammatory and anti-apoptotic effects. However, whether Gfi-1 has similar effects on H9c2 cardiomyocytes has not yet been reported. In this study, we explored the effect of Gfi-1 on lipopolysaccharide (LPS)-induced inflammatory responses and apoptosis in H9c2 cells. We found that LPS induced the increased expression of TNF-α and IL-6 in the LPS group. After transfection of the Gfi-1 overexpression plasmid, the expression of TNF-α and IL-6 decreased significantly in the LPS + Gfi-1 group. Gfi-1 clearly blocked LPS-induced NF-κB, TNF-α, TNFR1, cleaved-caspase-3 and cleaved-caspase-8 expression and increased Gfi-1 and Bcl-xL expression in H9c2 cells. Similarly, compared with the LPS group, Gfi-1 significantly decreased the expression of cleaved-caspase3/8 and increased the expression of Bcl-xL in the LPS + Gfi-1 group, as verified by immunocytochemical analysis. Furthermore, Gfi-1 markedly inhibited LPS-induced H9c2 cardiomyocyte apoptosis in the LPS + Gfi-1 group, as determined by TEM, TUNEL and flow cytometry. Taken together, these results demonstrate that Gfi-1 may have protective effects against LPS-induced inflammatory responses and apoptosis in H9c2 cells. Gfi-1 may be a novel molecule for treating septic cardiomyopathy.

Interleukin-5 deletion promotes sepsis-induced M1 macrophage differentiation, deteriorates cardiac dysfunction, and exacerbates cardiac injury via the NF-κB p65 pathway in mice

Inflammation plays a crucial role in sepsis-induced cardiac injury. The purpose of this study was to determine whether interleukin-5 (IL-5) affected lipopolysaccharide (LPS)-induced cardiac injury by regulating the inflammatory response. First, the expression level and source of cardiac IL-5 were examined, and the results showed that LPS treatment and cecal ligation decreased cardiac IL-5 expression in macrophages. In addition, LPS was used to establish a mouse sepsis model, and the effects of IL-5 deletion on cardiac injury, M1 macrophage differentiation and myocardial cell apoptosis were analyzed. The results showed that IL-5 deficiency significantly increased cardiac injury marker expression, worsened cardiac dysfunction, promoted M1 macrophage differentiation and exacerbated myocardial cell apoptosis in LPS-induced septic mice. The nuclear factor-kappa B (NF-κB) p65 pathway was inhibited by JSH-23, and the results showed that treatment with JSH-23 inhibited M1 macrophage differentiation and alleviated cardiac injury in LPS-treated IL-5-knockout mice. Furthermore, the effects of IL-5 deficiency on M1 macrophage differentiation and myocardial cell apoptosis were measured in vitro. The IL-5-mediated promotion of M1 macrophage differentiation was also reversed by S31-201, and the pro-apoptotic effect of IL-5 knockout on macrophage-mediated myocardial cell apoptosis was also reversed by JSH-23. In conclusion, we found that IL-5 knockout may exacerbate sepsis-induced cardiac injury by promoting M1 macrophage differentiation in mice. IL-5 may be a potential target for the clinical prevention of sepsis-related cardiac injury.

BML-111 treatment prevents cardiac apoptosis and oxidative stress in a mouse model of autoimmune myocarditis

Myocarditis is an inflammation of the myocardium that can progress to a more severe phenotype of dilated cardiomyopathy (DCM). Three main harmful factors determine this progression: inflammation, cell death, and oxidative stress. Lipoxins and their derivatives are endogenous proresolving mediators that induce the resolution of the inflammatory process. This study aims to determine whether these mediators play a protective role in a murine model of experimental autoimmune myocarditis (EAM) by treating with the lipoxin A₄ analog BML-111. We observed that EAM mice presented extensive infiltration areas that correlated with higher levels of inflammatory and cardiac damage markers. Both parameters were significantly reduced in BML-treated EAM mice. Consistently, cardiac dysfunction, hypertrophy, and emerging fibrosis detected in EAM mice was prevented by BML-111 treatment. At the molecular level, we demonstrated that treatment with BML-111 hampered apoptosis and oxidative stress induction by EAM. Moreover, both in vivo and in vitro studies revealed that these beneficial effects were mediated by activation of Nrf2 pathway through CaMKK2-AMPKα kinase pathway. Altogether, our data indicate that treatment with the lipoxin derivative BML-111 effectively alleviates EAM outcome and prevents cardiac dysfunction, thus, underscoring the therapeutic potential of lipoxins and their derivatives to treat myocarditis and other inflammatory cardiovascular diseases.

Bioinformatics-Based Study to Investigate Potential Differentially Expressed Genes and miRNAs in Pediatric Sepsis

BACKGROUND Sepsis is an extremely common health issue with a considerable mortality rate in children. Our understanding about the pathogenic mechanisms of sepsis is limited. The aim of this study was to identify the differential expression genes (DEGs) in pediatric sepsis through comprehensive analysis, and to provide specific insights for the clinical sepsis therapies in children. MATERIAL AND METHODS Three pediatric gene expression profiles (GSE25504, GSE26378, GSE26440) were downloaded from the Gene Expression Omnibus (GEO) database. The difference expression genes (DEGs) between pediatric sepsis and normal control group were screened with the GEO2R online tool. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses of the DEGs were performed. Cytoscape with CytoHubba were used to identify the hub genes. Finally, NetworkAnalyst was used to construct the targeted microRNAs (miRNAs) of the hub genes. RESULTS Totally, 160 overlapping upward genes and 61 downward genes were identified. In addition, 5 KEGG pathways, including hematopoietic cell lineage, Staphylococcus aureus infection, starch and sucrose metabolism, osteoclast differentiation, and tumor necrosis factor (TNF) signaling pathway, were significantly enriched using a database for labeling, visualization, and synthetic discovery. In combination with the results of the protein-protein interaction (PPI) network and CytoHubba, 9 hub genes including ITGAM, TLR8, IL1ß, MMP9, MPO, FPR2, ELANE, SPI1, and C3AR1 were selected. Combined with DEG-miRNAs visualization, 5 miRNAs, including has-miR-204-5p, has-miR-211-5p, has-miR-590-5p, and has-miR-21-5p, were predicted as possibly the key miRNAs. CONCLUSIONS Our findings will contribute to identification of potential biomarkers and novel strategies for pediatric sepsis treatment.

Overexpression of Annexin A1 Is an Independent Predictor of Longer Overall Survival in Epithelial Ovarian Cancer

BACKGROUND

Epithelial ovarian cancer (EOC) is the major gynecological cause of cancer deaths. Annexin A1 (ANXA1) protein has been implicated in the aggressiveness of several cancer types.

MATERIALS AND METHODS

This study retrospectively assessed ANXA1 expression in epithelial cells of 156 pre-chemotherapy EOC samples and 34 normal ovarian samples from patients treated at Salah Azaiez Institute. Using immunohistochemistry, ANXA1 expression was compared in normal versus cancer samples; correlations with clinicopathological features, including overall survival, were sought.

RESULTS

Fifty-two percent of tumor samples showed epithelial ANXA1 staining versus only 26% of normal samples (Fisher's exact test, p=0.00794). Epithelial ANXA1 expression was correlated with better overall survival in both univariate and multivariate analyses.

CONCLUSION

The possible contribution of ANXA1 overexpression to EOC outcome may be relevant to therapeutic strategies.