Inhibition of galectin-3 post-infarction impedes progressive fibrosis by regulating inflammatory profibrotic cascades

Central role of Galectin-3 at the cross-roads of cardiac inflammation and fibrosis: Implications for heart failure and transplantation

Cardiac inflammation and fibrosis are central pathogenic mechanisms leading to heart failure. Transplantation is still the treatment of choice for many patients undergoing end-stage heart failure who remain symptomatic despite optimal medical therapy. In spite of considerable progress, the molecular mechanisms linking inflammation, fibrosis and heart failure remain poorly understood. Galectin-3 (GAL3), a chimera-type member of the galectin family, has emerged as a critical mediator implicated in cardiac inflammatory, vascular and fibrotic processes through modulation of different cellular compartments including monocytes and macrophages, fibroblasts, endothelial cells and vascular smooth muscle cells via glycan-dependent or independent mechanisms. GAL3-driven circuits may hierarchically amplify cytokine production and function, immune cell activation and fibrosis cascades, influencing a wide range of cardiovascular disorders. Thus, GAL3 emerges as a potential therapeutic target to counteract aberrant inflammation and fibrosis during heart failure and a potential biomarker of heart failure and clinical outcome of heart transplantation.

LGALS3 regulates endothelial-to-mesenchymal transition via PI3K/AKT signaling pathway in silica-induced pulmonary fibrosis

Silicosis is a progressive and chronic occupational lung disease characterized by lung inflammation, silicotic nodule formation, and diffuse pulmonary fibrosis. Emerging evidence indicates that endothelial-mesenchymal transition (EndoMT) plays a crucial role in the development of silicosis. Herein, we conducted a SiO2-induced EndoMT model and established a mouse model with pulmonary fibrosis by silica. We identified that SiO2 effectively increased the expression of mesenchymal markers while decreasing the levels of endothelial markers in endothelial cells. It's further demonstrated that SiO2 induced the PI3K/Akt signaling pathway activation via LGALS3 synthesis. Next, interfering LGALS3 blocked the process of EndoMT by inhibiting the activity of PI3K/AKT signaling. In vivo, the administration of a specific PI3K inhibitor LY294002 significantly alleviated silica-induced pulmonary fibrosis. Collectively, these results identified that the LGALS3/PI3K/AKT pathway provided a rationale target for the clinical treatment and intervention of silicosis.

The Macrophage-Fibroblast Dipole in the Context of Cardiac Repair and Fibrosis

Stromal and immune cells and their interactions have gained the attention of cardiology researchers and clinicians in recent years as their contribution in cardiac repair is increasingly recognized. The repair process in the heart is a particularly critical constellation of complex molecular and cellular events and interactions that characteristically fail to ensure adequate recovery following injury, insult, or exposure to stress conditions in this regeneration-hostile organ. The tremendous consequence of this pronounced inability to maintain homeostatic states is being translated in numerous ways promoting progress into heart failure, a deadly, irreversible condition requiring organ transplantation. Fibrosis is in fact a repair response eventually promoting cardiac dysfunction and cardiac fibroblasts are the major cellular players in this process, overproducing collagens and other extracellular matrix components when activated. On the other hand, macrophages may differentially affect fibroblasts and cardiac repair depending on their status and subsets. The opposite interaction is also probable. We discuss here the multifaceted aspects and crosstalk of this cell dipole and the opportunities it may offer for beneficial manipulation approaches that will hopefully lead to progress in heart disease interventions.

Matricellular proteins: From cardiac homeostasis to immune regulation

Tissue repair after myocardial injury is a complex process involving changes in all aspects of the myocardial tissue, including the extracellular matrix (ECM). The ECM is composed of large structural proteins such as collagen and elastin and smaller proteins with major regulatory properties called matricellular proteins. Matricellular cell proteins exert their functions and elicit cellular responses by binding to structural proteins not limited to interactions with cell surface receptors, cytokines, or proteases. At the same time, matricellular proteins act as the "bridge" of information exchange between cells and ECM, maintaining the integrity of the cardiac structure and regulating the immune environment, which is a key factor in determining cardiac homeostasis. In this review, we present an overview of the identified matricellular proteins and summarize the current knowledge regarding their roles in maintaining cardiac homeostasis and regulating the immune system.

Surgical Outcomes of Mitomycin-C Augmented Trabeculectomy in Neovascular Glaucoma and Prognostic Factors for Surgical Failure in Thailand

Purpose

To evaluate the surgical outcomes and identify ocular and systemic prognostic factors of trabeculectomy with mitomycin C (MMC) in the eyes of patients with neovascular glaucoma (NVG) in Thailand.

Patients and Methods

This retrospective study was conducted by reviewing records of Thai patients with NVG who underwent trabeculectomy with MMC between 2013 and 2022. Criterion failure was defined as intraocular pressure (IOP) >21 mmHg or less than a 20% reduction below baseline on two consecutive study visits after 3 months, IOP ≤5 mmHg on two consecutive study visits after 3 months, reoperation for glaucoma, and loss of light perception. Kaplan-Meier survival curves were used to examine success rates, and risk factors were analyzed using Cox's proportional hazard model.

Results

The study included 106 eyes of 106 patients with a mean age of 57 years (range, 27-87 years). The cause of NVG was proliferative diabetic retinopathy (PDR) in 63 eyes (59.43%), central retinal vein occlusion (CRVO) in 39 eyes (36.79%), and ocular ischemic syndrome (OIS) in 4 eyes (3.77%). The cumulative probability of success in the first year was 73.6% with anti-glaucoma medication and 54.7% without medication. The multivariate model demonstrated that major cardiovascular events (hazard ratio [HR], 2.778 p=0.001) and preoperative systemic antiglaucoma medication use (HR, 1.837, p=0.045) were prognostic factors for surgical failure among all NVG patients. Postoperative manipulation with a subconjunctival injection of MMC occurred significantly more frequently in the failure group (HR, 3.100; p<0.001).

Conclusion

Trabeculectomy with MMC effectively reduced the elevated IOP associated with NVG in Thailand. Underlying systemic diseases involving major vascular events and the use of adjunct systemic IOP-lowering medications were prognostic factors for surgical failure.

Ischemic-Preconditioning Induced Serum Exosomal miR-133a-3p Improved Post-Myocardial Infarction Repair via Targeting LTBP1 and PPP2CA

Background

Ischemic preconditioning-induced serum exosomes (IPC-exo) protected rat heart against myocardial ischemia/reperfusion injury. However, whether IPC-exo regulate replacement fibrosis after myocardial infarction (MI) and the underlying mechanisms remain unclear. MicroRNAs (miRs) are important cargos of exosomes and play an essential role in cardioprotection. We aim to investigate whether IPC-exo regulate post-MI replacement fibrosis by transferring cardioprotective miRs and its action mechanism.

Methods

Exosomes obtained from serum of adult rats in control (Con-exo) and IPC groups were identified and analyzed, subsequently intracardially injected into MI rats following ligation. Their miRs profiles were identified using high-throughput miR sequencing to identify target miRs for bioinformatics analysis. Luciferase reporter assays confirmed target genes of selected miRs. IPC-exo transfected with selected miRs antagomir or NC were intracardially administered to MI rats post-ligation. Cardiac function and degree of replacement fibrosis were detected 4 weeks post-MI.

Results

IPC-exo exerted cardioprotective effects against excessive replacement fibrosis. MiR sequencing and RT-qPCR identified miR-133a-3p as most significantly different between IPC-exo and Con-exo. MiR-133a-3p directly targeted latent transforming growth factor beta binding protein 1 (LTBP1) and protein phosphatase 2, catalytic subunit, alpha isozyme (PPP2CA). KEGG analysis showed that transforming growth factor-β (TGF-β) was one of the most enriched signaling pathways with miR-133a-3p. Comparing to injection of IPC-exo transfected with miR-133a-3p antagomir NC, injecting IPC-exo transfected with miR-133a-3p antagomir abolished protective effects of IPC-exo on declining excessive replacement fibrosis and cardiac function enhancement, while increasing the messenger RNA and protein expression of LTBP1, PPP2CA, and TGF-β1in MI rats.

Conclusion

IPC-exo inhibit excessive replacement fibrosis and improve cardiac function post-MI by transferring miR-133a-3p, the mechanism is associated with directly targeting LTBP1 and PPP2CA, and indirectly regulating TGF-β pathway in rats. Our finding provides potential therapeutic effect of IPC-induced exosomal miR-133a-3p for cardiac repair.

Zinc ions regulate mitochondrial quality control in neurons under oxidative stress and reduce PANoptosis in spinal cord injury models via the Lgals3-Bax pathway

Spinal cord injury is a serious traumatic nervous system disorder characterized by extensive neuronal apoptosis. Oxidative stress, a key factor in neuronal apoptosis, leads to the accumulation of reactive oxygen species, making mitochondrial quality control within cells crucial. Previous studies have demonstrated zinc's anti-inflammatory and anti-apoptotic properties in protecting mitochondria during spinal cord injury treatment, yet the precise mechanisms remain elusive. Single-cell sequencing analysis has identified Lgals3 and Bax as core genes in apoptosis. This study aimed to investigate whether zinc ions protect intracellular mitochondria by inhibiting the apoptotic proteins Lgals3 and Bax. We elucidated zinc ions' key role in mitigating mitochondrial quality control dysfunction triggered by oxidative stress and confirmed this was achieved by targeting the Lgals3-Bax pathway. Zinc's inhibitory effect on this pathway not only preserved mitochondrial integrity but also significantly reduced PANoptosis after spinal cord injury. Under oxidative stress, zinc ion regulation of mitochondrial quality control reveals an organelle-targeted therapeutic strategy, offering a novel approach for more precise treatment of spinal cord injury.

Inflammation-Derived and Clinical Indicator-Based Predictive Model for Ischemic Stroke Recovery

BACKGROUND

Neuroinflammatory responses are closely associated with poststroke prognosis severity. This study aimed to develop a predictive model, combining inflammation-derived markers and clinical indicators, for distinguishing functional outcomes in patients with subacute ischemic stroke.

METHODS AND RESULTS

Based on activities of daily living assessments, ischemic stroke participants were categorized into groups with little effective (LE) recovery and obvious effective (OE) recovery. Initial biocandidates were identified by overlapping differentially expressed proteins from proteomics of clinical serum samples (5 LE, 5 OE, and 6 healthy controls) and differentially expressed genes from an RNA sequence of the ischemic cortex in middle cerebral artery occlusion mice (n=3). Multidimensional validations were conducted in ischemia-reperfusion models and a clinical cohort (15 LE, 11 OE, and 18 healthy controls). Models of robust biocandidates combined with clinical indicators were developed with machine learning in the training data set and prediction in another test data set (15 LE and 11 OE). We identified 194 differentially expressed proteins (LE versus healthy controls) and 174 differentially expressed proteins (OE versus healthy controls) in human serum, and 5121 differentially expressed genes (day 3) and 5906 differentially expressed genes (day 7) in middle cerebral artery occlusion mice cortex. Inflammation-derived biomarkers TIMP1 (tissue inhibitor metalloproteinase-1) and galactosidase-binding protein LGLAS3 (galectin-3) exhibited robust increases under ischemic injury in mice and humans. TIMP1 and LGALS3 coupled with clinical indicators (hemoglobin, low-density lipoprotein cholesterol, and uric acid) were developed into a combined model for differentiating functional outcome with high accuracy (area under the curve, 0.8).

CONCLUSIONS

The combined model is a valuable tool for evaluating prognostic outcomes, and the predictive factors can facilitate development of better treatment strategies.

Understanding Galectin-3's Role in Diastolic Dysfunction: A Contemporary Perspective

Diastolic dysfunction, a prevalent condition characterized by impaired relaxation and filling of the left ventricle, significantly contributes to heart failure with preserved ejection fraction (HFpEF). Galectin-3, a β-galactoside-binding lectin, has garnered attention as a potential biomarker and mediator of fibrosis and inflammation in cardiovascular diseases. This comprehensive review investigates the impact of galectin-3 on diastolic dysfunction. We explore its molecular mechanisms, including its involvement in cellular signaling pathways and interaction with components of the extracellular matrix. Evidence from both animal models and clinical studies elucidates galectin-3's role in cardiac remodeling, inflammation, and fibrosis, shedding light on the underlying pathophysiology of diastolic dysfunction. Additionally, we examine the diagnostic and therapeutic implications of galectin-3 in diastolic dysfunction, emphasizing its potential as both a biomarker and a therapeutic target. This review underscores the significance of comprehending galectin-3's role in diastolic dysfunction and its promise in enhancing diagnosis and treatment approaches for HFpEF patients.

Role of macrophage polarization in heart failure and traditional Chinese medicine treatment

Heart failure (HF) has a severe impact on public health development due to high morbidity and mortality and is associated with imbalances in cardiac immunoregulation. Macrophages, a major cell population involved in cardiac immune response and inflammation, are highly heterogeneous and polarized into M1 and M2 types depending on the microenvironment. M1 macrophage releases inflammatory factors and chemokines to activate the immune response and remove harmful substances, while M2 macrophage releases anti-inflammatory factors to inhibit the overactive immune response and promote tissue repair. M1 and M2 restrict each other to maintain cardiac homeostasis. The dynamic balance of M1 and M2 is closely related to the Traditional Chinese Medicine (TCM) yin-yang theory, and the imbalance of yin and yang will result in a pathological state of the organism. Studies have confirmed that TCM produces positive effects on HF by regulating macrophage polarization. This review describes the critical role of macrophage polarization in inflammation, fibrosis, angiogenesis and electrophysiology in the course of HF, as well as the potential mechanism of TCM regulation of macrophage polarization in preventing and treating HF, thereby providing new ideas for clinical treatment and scientific research design of HF.

Galectin-3 promotes fibrosis in ovarian endometriosis

Objective

This study aimed to investigate the potential role of galectin-3 (Gal-3) in the pathogenesis of fibrotic alterations in ovarian endometriosis (OVE).

Methods

In this study, we collected the ectopic endometrial tissues and eutopic endometrial tissues from 31 OVE patients treated by laparoscopy, and the eutopic endometrial tissues from 23 non-OVE patients with leiomyoma or other benign diseases were used as control. Hematoxylin and eosin (H&E) and Masson's trichrome staining were utilized for histopathological assessment. The primary normal endometrial stromal cells (NESC), ectopic endometrial stromal cells (ECSC), and eutopic endometrial stromal cells (EUSC) were isolated. Gal-3 overexpression plasmids (Gal-OE) and short hairpin RNA targeting Gal-3 (Gal-3-shRNA) were transfected into the immortalized human endometriotic cell line 12Z, respectively. RT-qPCR, Western blot analysis, and immunohistochemistry were used to detect the mRNA and protein expression levels of Gal-3, type I collagen (COL-1), connective tissue growth factor (CTGF) and α-smooth muscle actin (α-SMA), respectively.

Results

H&E and Masson staining showed that ovarian ectopic endometrium exhibited glandular hyperplasia, high columnar glandular epithelium, apical plasma secretion, more subnuclear vacuoles, and obvious fibrosis, compared with normal endometrium. The mRNA and protein levels of Gal-3 , CTGF, α-SMA, and COL-1 were all upregulated in the ectopic endometrial tissues of OVE patients compared to the eutopic endometrial tissues from OVE patients and non-OVE patients. Moreover, ECSC expressed higher levels of Gal-3, CTGF, α-SMA, and COL-1 than EUSC and NESC. Follow-up investigations demonstrated that the Gal-3 overexpression substantially increased fibrosis-related markers including CTGF, α-SMA, and COL-1 within the 12Z cell line. Conversely, Gal-3 knockdown showed the opposite effects.

Conclusion

Gal-3 promotes fibrosis in OVE, positioning it as a prospective therapeutic target for mitigating fibrosis in endometriosis.

Galectin-3 and Severity of Liver Fibrosis in Metabolic Dysfunction-Associated Fatty Liver Disease

Metabolic dysfunction-associated Fatty Liver Disease (MAFLD) is a chronic liver disease characterized by the accumulation of fat in the liver and hepatic steatosis, which can progress to critical conditions, including Metabolic dysfunction-associated Steatohepatitis (MASH), liver fibrosis, hepatic cirrhosis, and hepatocellular carcinoma. Galectin-3, a member of the galectin family of proteins, has been involved in cascades that are responsible for the pathogenesis and progression of liver fibrosis in MAFLD. This review summarizes the present understanding of the role of galectin-3 in the severity of MAFLD and its associated liver fibrosis. The article assesses the underlying role of galectin-3-mediated fibrogenesis, including the triggering of hepatic stellate cells, the regulation of extracellular degradation, and the modulation of immune reactions and responses. It also highlights the assessments of the potential diagnostic and therapeutic implications of galectin-3 in liver fibrosis during MAFLD. Overall, this review provides insights into the multifaceted interaction between galectin-3 and liver fibrosis in MAFLD, which could lead to the development of novel strategies for diagnosis and treatment of this prevalent liver disease.

Unraveling the role of galectin-3 in cardiac pathology and physiology

Galectin-3 (Gal-3) is a carbohydrate-binding protein with multiple functions. Gal-3 regulates cell growth, proliferation, and apoptosis by orchestrating cell-cell and cell-matrix interactions. It is implicated in the development and progression of cardiovascular disease, and its expression is increased in patients with heart failure. In atherosclerosis, Gal-3 promotes monocyte recruitment to the arterial wall boosting inflammation and atheroma. In acute myocardial infarction (AMI), the expression of Gal-3 increases in infarcted and remote zones from the beginning of AMI, and plays a critical role in macrophage infiltration, differentiation to M1 phenotype, inflammation and interstitial fibrosis through collagen synthesis. Genetic deficiency of Gal-3 delays wound healing, impairs cardiac remodeling and function after AMI. On the contrary, Gal-3 deficiency shows opposite results with improved remodeling and function in other cardiomyopathies and in hypertension. Pharmacologic inhibition with non-selective inhibitors is also protective in cardiac disease. Finally, we recently showed that Gal-3 participates in normal aging. However, genetic absence of Gal-3 in aged mice exacerbates pathological hypertrophy and increases fibrosis, as opposed to reduced fibrosis shown in cardiac disease. Despite some gaps in understanding its precise mechanisms of action, Gal-3 represents a potential therapeutic target for the treatment of cardiovascular diseases and the management of cardiac aging. In this review, we summarize the current knowledge regarding the role of Gal-3 in the pathophysiology of heart failure, atherosclerosis, hypertension, myocarditis, and ischemic heart disease. Furthermore, we describe the physiological role of Gal-3 in cardiac aging.