Berberine inhibits NLRP3 inflammasome activation by regulating mTOR/mtROS axis to alleviate diabetic cardiomyopathy

Exploring the Multi-Faceted Effects of Berberine in Ameliorating Diastolic Dysfunction in Rats with Heart Failure with Preserved Ejection Fraction

Heart failure with preserved ejection fraction (HFpEF), marked by cardiac diastolic dysfunction, contributes to half of all heart failure cases globally and poses a significant public health challenge. Effective therapies for HFpEF are rare, largely due to its complex and heterogeneous pathophysiology, which often involves multiple comorbidities. Berberine (BBR), an isoquinoline alkaloid, has demonstrated beneficial effects on multiple metabolic and cardiovascular disorders; however, its impact on cardiac diastolic dysfunction in HFpEF remains poorly understood. In this study, we utilized a rat model of HFpEF induced by a sustained high-fat/high-sucrose (HFHS) diet to explore the impact and mechanisms of BBR on diastolic dysfunction. The results revealed that BBR administration effectively alleviated cardiac diastolic dysfunction and alleviated extracardiac comorbidities, including increased weight, impaired glucose tolerance, hypercholesterolemia and hypertension, in rats fed an HFHS diet. Furthermore, BBR mitigated myocardial inflammation, oxidative stress, microvascular endothelial dysfunction, and notably restored the disturbed NO-cGMP-PKG pathway. Additionally, BBR reduced myocardial fibrosis and inhibited the abnormally activated TGF-β/Smads signaling. Moreover, BBR attenuated the systemic inflammation and corrected immune dysregulation in an HFHS diet-fed rats. Our study suggests that BBR exhibits multi-beneficial effects in the prevention and management of HFpEF, demonstrating its potential as a holistic therapeutic candidate for HFpEF.

Effects of remote ischemic preconditioning and/or erythropoietin on lung injury induced by skeletal ischemia reperfusion: role of the NLRP3 inflammasome

BACKGROUND AND OBJECTIVES

Remote ischemic preconditioning (RIPC) diminishes multi-organ failure induced by skeletal muscle ischemia and reperfusion (S-I/R). The current study investigated whether skeletal RIPC protection against S-I/R-induced acute lung injury (ALI) could be facilitated following simultaneous exposure to the glycoprotein hormone erythropoietin (EPO) in rats and whether this interaction is modulated by the NLRP3 inflammasome.

METHODS

S-I/R challenge was performed by 3-h ischemia followed by 3-h reperfusion of the right hindlimb, whereas RIPC involved three 20-min brief consecutive I/R cycles of the contralateral hindlimb.

RESULTS

The lung injurious response to S-I/R was verified by: (i) decreases in minute respiratory volume (MRV), forced expiratory volume 1 (FEV1) and functional vital capacity (FVC), (ii) increases in respiratory rate (RR), (iii) falls in lung surfactant protein-D (SP-D) and rises in of lung plasminogen activator inhibitor-1 (PAI-1) and intercellular adhesion molecule-1 (ICAM-1), and (iv) disruption of alveolar architecture. These lung defects were partially amended by RIPC or EPO (500 or 5000 IU/kg). Further, the prior exposure to RIPC plus EPO-500 was more effective than separate interventions in rectifying ALI damages. Molecularly, the dual RIPC/EPO-500 regimen was also more effective in reversing the S-I/R-associated increments in pulmonary expressions of NLRP3 and related inflammatory (TLR4, MyD88, TRAF, NF-κB, TNF-α, IL-1β, and IL-18), apoptotic (ASC, procaspse-1, caspase-1), and microRNA signals (increases in miR-21 and decreases miR-495).

CONCLUSION

These findings suggest a pivotal role for the suppression of NLRP3 inflammasome and interconnected cellular offenses in the augmented therapeutic potential of the RIPC/EPO-500 regimen against S-I/R-induced ALI.

Berberine Suppresses Influenza A Virus-Triggered Pyroptosis in Macrophages via Intervening in the mtROS-MAVS-NLRP3 Inflammasome Pathway

Infection with influenza A virus (IAV) may trigger excessive inflammatory responses, leading to severe viral pneumonia and accelerating disease progression. Therefore, controlling these excessive inflammatory responses is crucial for the prevention and treatment of pneumonia caused by IAV. Berberine (BBR), an isoquinoline alkaloid extracted from traditional Chinese medicine, possesses extensive pharmacological activities. However, its immunoregulatory effects and molecular mechanisms in the context of IAV infection require further investigation. This study explored the impact of BBR on macrophage pyroptosis and inflammatory responses induced by IAV infection. Our findings revealed that BBR effectively inhibits the release of IL-1β and TNF-α induced by IAV infection and suppresses gasdermin D (GSDMD)-mediated pyroptosis in a dose-dependent manner. Further research indicates that BBR alleviates macrophage pyroptosis and inflammatory responses in IAV-infected cells by reducing the release of mitochondrial reactive oxygen species (mtROS), inhibiting mitochondrial antiviral signaling protein (MAVS) expression and blocking the activation of the NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome. Experiments using siRNA to knockdown MAVS further confirmed the pivotal role of MAVS in BBR's inhibition of IAV-induced macrophage pyroptosis. This study provides a scientific basis for the application of BBR as an anti-inflammatory drug in the treatment of inflammatory diseases caused by IAV infection and directs future research endeavors.

The role of NLRP3 inflammasome in multiple sclerosis: pathogenesis and pharmacological application

Multiple sclerosis (MS) is widely acknowledged as a chronic inflammatory autoimmune disorder characterized by central nervous system (CNS) demyelination and neurodegeneration. The hyperactivation of immune and inflammatory responses is recognized as a pivotal factor contributing to the pathogenesis and progression of MS. Among various immune and inflammatory reactions, researchers have increasingly focused on the inflammasome, a complex of proteins. The initiation and activation of the inflammasome are intricately involved in the onset of MS. Notably, the NLRP3 inflammasome, the most extensively studied member of the inflammasome complex, is closely linked with MS. This review will delve into the roles of the NLRP3 inflammasome in the pathogenesis and progression of MS. Additionally, therapeutic strategies targeting the NLRP3 inflammasome for the treatment of MS, including natural compounds, autophagy regulators, and other small molecular compounds, will be detailed in this review.

The molecular mechanism of berberine affecting psoriasis skin inflammation by regulating keratinocyte pyroptosis via the p38 MAPK/NF-κB pathway

Berberine (BBR), a Rhizoma Coptis-sourced isoquinoline alkaloid, is an effective drug for psoriasis treatment with its therapeutic mechanism remaining unclear. We delved into the mechanism of BBR affecting psoriatic skin inflammation by regulating keratinocyte pyroptosis. A psoriasis-like skin inflammation mouse model was induced by imiquimod (IMQ) and treated with BBR and a p38 activator anisomycin. Human epidermal keratinocytes (HEKs) were stimulated with five chemokines (M5) [interleukin (IL)-17A, IL-22A, oncostatin M, tumor necrosis factor-α, IL-1α] to simulate psoriasis immune microenvironment, then treated with BBR and anisomycin. Psoriasis skin lesions, skin tissue damage, cell viability and death, and gasdermin D-N (GSDMD-N) and NOD-like receptor protein 3 (NLRP3) positive cell numbers were assessed. The p38 mitogen-activated protein kinase (MAPK)/nuclear factor-kappa B (NF-κB) pathway and levels of the NLRP3/GSDMD pathway-related proteins and inflammatory factors were determined. BBR alleviated M5-induced HEK pyroptosis by inactivating NLRP3 inflammasomes. BBR inhibited the p38 MAPK/NF-κB pathway, and its effects on HEKs were partly averted by activating the p38 MAPK/NF-κB pathway. BBR repressed NLRP3 inflammasome activation and pyroptosis by inhibiting the p38 MAPK/NF-κB pathway. Collectively, BBR suppressed keratinocyte NLRP3/GSDMD pathway pyroptosis by suppressing the p38 MAPK/NF-κB pathway, thereby affecting psoriasis skin inflammation.

Effects of Ellagic Acid and Berberine on Hind Limb Ischemia Reperfusion Injury: Pathways of Apoptosis, Pyroptosis, and Oxidative Stress

Background and Objectives: Hind limb ischemia-reperfusion (I/R) injury is a serious clinical condition that requires urgent treatment and develops as a result of a sudden decrease in blood flow in the extremity. Antioxidant combinations are frequently used in diseases today. This study aimed to investigate and compare the effectiveness of ellagic acid (EA) and berberine (BER), which are important antioxidants, and the combination on hind limb I/R injury to evaluate their therapeutic power. Materials and Methods: Thirty-five male Sprague Dawley rats were randomly divided into five groups: sham, I/R, EA+I/R, BER+I/R, and EA/BER+I/R. In the I/R procedure, the infrarenal abdominal aorta was clamped and reperfused for 2 h. EA (100 mg/kg, ip) and BER (200 mg/kg, ip) were administered in the 75th minute of ischemia. Oxidative stress markers (MDA, GSH, SOD, and CAT) and TNF-α were measured. Apoptosis (Bax, Bcl-2, and Cleaved caspase-3) and pyroptosis (Nrf2, NLRP3, and Gasdermin D) pathways were evaluated via Western blot. Muscle tissue was examined histopathologically by hematoxylin eosin staining. One-way ANOVA and post hoc LSD tests were applied for statistical analyses (p < 0.05). Results: Bax levels increased in the ischemia group and decreased with EA and BER (p < 0.05). Bcl-2 levels decreased in the ischemia group but increased with EA and BER (p < 0.05). The highest level of the Bax/Bcl-2 ratio was in the I/R group (p < 0.05). Cleaved caspase 3 was higher in the other groups compared to the sham group (p < 0.05). While Nrf2 decreased in the I/R group, NLRP3 and Gasdermin D increased; EA and BER normalized these levels (p < 0.05). In the histopathological analysis, a combination of EA and BER reduced damage (p < 0.05). TNF-α levels were similar between groups (p > 0.05). MDA levels were reduced by EA and BER, but GSH, SOD, and CAT levels were increased (p < 0.05). Conclusions: It was concluded that TNF-α levels depend on the degree and duration of inflammation and that no difference was found in relation to duration in this study. As a result, EA, BER, and their combination could be potential treatment agents on hind limb I/R injury with these positive effects.

The intricate interactions between inflammasomes and bacterial pathogens: Roles, mechanisms, and therapeutic potentials

Inflammasomes are intracellular multiprotein complexes that consist of a sensor, an adaptor, and a caspase enzyme to cleave interleukin (IL)-1β and IL-18 into their mature forms. In addition, caspase-1 and -11 activation results in the cleavage of gasdermin D to form pores, thereby inducing pyroptosis. Activation of the inflammasome and pyroptosis promotes host defense against pathogens, whereas dysregulation of the inflammasome can result in various pathologies. Inflammasomes exhibit versatile microbial signal detection, directly or indirectly, through cellular processes, such as ion fluctuations, reactive oxygen species generation, and the disruption of intracellular organelle function; however, bacteria have adaptive strategies to manipulate the inflammasome by altering microbe-associated molecular patterns, intercepting innate pathways with secreted effectors, and attenuating inflammatory and cell death responses. In this review, we summarize recent advances in the diverse roles of the inflammasome during bacterial infections and discuss how bacteria exploit inflammasome pathways to establish infections or persistence. In addition, we highlight the therapeutic potential of harnessing bacterial immune subversion strategies against acute and chronic bacterial infections. A more comprehensive understanding of the significance of inflammasomes in immunity and their intricate roles in the battle between bacterial pathogens and hosts will lead to the development of innovative strategies to address emerging threats posed by the expansion of drug-resistant bacterial infections.

Ferroptosis in diabetic cardiomyopathy: from its mechanisms to therapeutic strategies

Diabetic cardiomyopathy (DCM) is defined as structural and functional cardiac abnormalities in diabetes, and cardiomyocyte death is the terminal event of DCM. Ferroptosis is iron-dependent oxidative cell death. Evidence has indicated that iron overload and ferroptosis play important roles in the pathogenesis of DCM. Mitochondria, an important organelle in iron homeostasis and ROS production, play a crucial role in cardiomyocyte ferroptosis in diabetes. Studies have shown some anti-diabetic medicines, plant extracts, and ferroptosis inhibitors might improve DCM by alleviating ferroptosis. In this review, we systematically reviewed the evidence of ferroptosis in DCM. Anti-ferroptosis might be a promising therapeutic strategy for the treatment of DCM.

Pyroptosis in health and disease: mechanisms, regulation and clinical perspective

Pyroptosis is a type of programmed cell death characterized by cell swelling and osmotic lysis, resulting in cytomembrane rupture and release of immunostimulatory components, which play a role in several pathological processes. Significant cellular responses to various stimuli involve the formation of inflammasomes, maturation of inflammatory caspases, and caspase-mediated cleavage of gasdermin. The function of pyroptosis in disease is complex but not a simple angelic or demonic role. While inflammatory diseases such as sepsis are associated with uncontrollable pyroptosis, the potent immune response induced by pyroptosis can be exploited as a therapeutic target for anti-tumor therapy. Thus, a comprehensive review of the role of pyroptosis in disease is crucial for further research and clinical translation from bench to bedside. In this review, we summarize the recent advancements in understanding the role of pyroptosis in disease, covering the related development history, molecular mechanisms including canonical, non-canonical, caspase 3/8, and granzyme-mediated pathways, and its regulatory function in health and multiple diseases. Moreover, this review also provides updates on promising therapeutic strategies by applying novel small molecule inhibitors and traditional medicines to regulate pyroptosis. The present dilemmas and future directions in the landscape of pyroptosis are also discussed from a clinical perspective, providing clues for scientists to develop novel drugs targeting pyroptosis.

Berberine Targets PKM2 to Activate the t-PA-Induced Fibrinolytic System and Improves Thrombosis

BACKGROUND

Arterial thrombosis, a condition in which thrombi form in arteries, can lead to various acute cardiovascular diseases and impact the quality of life and survival of patients. Berberine (BBR), a quaternary ammonium alkaloid, has been shown to treat these diseases. However, further exploration is needed to understand underlying mechanisms of BBR.

METHODS AND RESULTS

Rats were administered BBR via intramuscular injection. Then, an FeCl3-coated filter paper was applied to a carotid artery to induce thrombosis. The size of the thrombus and the blood flow velocity were evaluated by carotid ultrasound. The shape of the thrombus was observed using staining and microscopy. The expression levels of mRNA and proteins were verified. Additionally, mass spectrometry and single-cell RNA sequencing analysis were conducted. The administration of BBR resulted in a significant reduction in the thrombus area and an extension of the thrombus-clogging time. Furthermore, BBR administration effectively reversed the decreasing tissue-plasminogen activator (t-PA) expression and alterations in fibrinolysis system of model group. Additionally, the expression of PKM2 was suppressed following BBR administration, and the overexpression of PKM2 inhibited t-PA expression.

CONCLUSIONS

BBR ameliorates thrombosis by modulating expression of PKM2, subsequently impacting the expression of t-PA within fibrinolytic system. These preliminary findings suggest that BBR could be a potential preventive and therapeutic strategy for arterial thromboembolic diseases.

Diabetic cardiomyopathy: Importance of direct evidence to support the roles of NOD-like receptor protein 3 inflammasome and pyroptosis

Recently, the roles of pyroptosis, a form of cell death induced by activated NOD-like receptor protein 3 (NLRP3) inflammasome, in the pathogenesis of diabetic cardiomyopathy (DCM) have been extensively investigated. However, most studies have focused mainly on whether diabetes increases the NLRP3 inflammasome and associated pyroptosis in the heart of type 1 or type 2 diabetic rodent models, and whether various medications and natural products prevent the development of DCM, associated with decreased levels of cardiac NLRP3 inflammasome and pyroptosis. The direct link of NLRP3 inflammasome and associated pyroptosis to the pathogenesis of DCM remains unclear based on the limited evidence derived from the available studies, with the approaches of NLRP3 gene silencing or pharmaceutical application of NLRP3 specific inhibitors. We thus emphasize the requirement for more systematic studies that are designed to provide direct evidence to support the link, given that several studies have provided both direct and indirect evidence under specific conditions. This editorial emphasizes that the current investigation should be circumspect in its conclusion, i.e., not overemphasizing its role in the pathogenesis of DCM with the fact of only significantly increased expression or activation of NLRP3 inflammasome and pyroptosis in the heart of diabetic rodent models. Only clear-cut evidence-based causative roles of NLRP3 inflammasome and pyroptosis in the pathogenesis of DCM can help to develop effective and safe medications for the clinical management of DCM, targeting these biomarkers.