Quercetin Inhibits Pyroptosis in Diabetic Cardiomyopathy through the Nrf2 Pathway

ROS-mediated ferroptosis and pyroptosis in cardiomyocytes: An update

The cardiomyocyte is an essential component of the heart, communicating and coordinating with non-cardiomyocytes (endothelial cells, fibroblasts, and immune cells), and are critical for the regulation of structural deformation, electrical conduction, and contractile properties of healthy and remodeled myocardium. Reactive oxygen species (ROS) in cardiomyocytes are mainly produced by the mitochondrial oxidative respiratory chain, nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX), xanthine oxidoreductase (XOR), monoamine oxidase (MAO), and p66shc. Under physiological conditions, ROS are involved in the regulation of cardiac development and cardiomyocyte maturation, cardiac calcium handling, and excitation-contraction coupling. In contrast, dysregulation of ROS metabolism is involved in the development and progression of cardiovascular diseases (CVDs), including myocardial hypertrophy, hyperlipidemia, myocardial ischemia/reperfusion injury, arrhythmias and diabetic cardiomyopathy. Further oxidative stress induced by ROS dyshomeostasis was found to be the major reason for cardiomyocyte death in cardiac diseases, and in recent years, ferroptosis induced by oxidative stress have been considered to be fatal to cardiomyocytes. In addition, ROS is also a key trigger for the activation of pyroptosis, which induces and exacerbates the inflammatory response caused by various cardiac diseases and plays a critical role in CVDs. Therefore, in this review, the sources and destinations of ROS in cardiomyocytes will be systematically addressed, so as to reveal the molecular mechanisms by which ROS accumulation triggers cardiomyocyte ferroptosis and pyroptosis under pathological conditions, and provide a new concept for the research and treatment of heart-related diseases.

Cranberry Extract Ameliorates Diabetic Cognitive Impairment in Rats Via LncRNA GAS-5 Downregulation and Pyroptosis Pathway Inhibition

The pathophysiology of diabetes-induced brain injury involves pyroptosis, an inflammatory programmed cell death. This study aimed to investigate the potential protective effect of cranberry extract (CE) against diabetes-induced brain injury. Type 1 diabetes was induced by intraperitoneal injection of streptozotocin in rats. Brain tissue samples were investigated for biochemical determination of the reduced glutathione (GSH), superoxide dismutase (SOD), and malondialdehyde (MDA), and the quantitative RT-PCR for the gene expression of glial cell-derived neurotrophic factor (GDNF), lncRNA GAS-5, and pyroptosis markers. ELISA was used to determine the caspase-1 level and immunohistochemical staining for assessing IL-1β. Prophylactic dosing of the CE in diabetic rats improved cognitive behavior and significantly suppressed MDA concentration, pyroptosis genes expression (gasdermin D and caspase 1), and lncRNA GAS-5. In addition, CE significantly elevated GSH concentration, SOD activity, and gene expression of GDNF and markedly reduced IL-1β positive stained cells score in the brain. Phytochemical characterization of the CE by FT-IR and UPLC-PDA-MS/MS revealed cyanidin arabinoside, procyanidins, quercetin, and isorhamnetin as key components. CE protects against diabetes-induced cognitive dysfunction in rats by targeting redox-related signaling pathways and inducing an anti-inflammatory effect. LncRNA GAS-5 downregulation and pyroptosis pathway inhibition may contribute to its beneficial effects, suggesting its therapeutic potential.

Non-coding RNAs modulate pyroptosis in diabetic cardiomyopathy: A comprehensive review

Diabetic cardiomyopathy (DCM) is a leading cause of heart failure (HF) among individuals with diabetes, presenting a significant medical challenge due to its complex pathophysiology and the lack of targeted therapies. Pyroptosis, a pro-inflammatory form of programmed cell death (PCD), is the predominant mode of cell death in the primary resident cells involved in DCM. It has been reported to be critical in DCM's onset, progression, and pathogenesis. Non-coding RNAs (ncRNAs), diverse transcripts lacking protein-coding potential, are essential for cellular physiology and the progression of various diseases. Increasing evidence indicates that ncRNAs are pivotal in the pathogenesis of DCM by regulating pyroptosis. This observation suggests that targeting the regulation of pyroptosis by ncRNAs may offer a novel therapeutic approach for DCM. However, a comprehensive review of this topic is currently lacking. Our objective is to elucidate the regulatory role of ncRNAs in pyroptosis associated with DCM and to elucidate the relationships among these factors. Additionally, we explored how ncRNAs influence pyroptosis and contribute to the pathophysiology of DCM. By doing so, we aim to identify new research targets for the clinical diagnosis and treatment of DCM.

A comprehensive review on diabetic cardiomyopathy (DCM): histological spectrum, diagnosis, pathogenesis, and management with conventional treatments and natural compounds

Diabetic complications are among the most pressing health issues currently. Cardiovascular problems, particularly diabetic cardiomyopathy (DCM), are responsible for almost 80% of diabetic deaths. Because of the increasing prevalence of diabetes and the increased threat of death from its consequences, researchers are searching for new pharmaceutical targets to delay or cure it. Currently, there are a few medicines available for the treatment of DCM, some of which have serious side effects. To address this issue, researchers are focusing on natural products. Thus, in this review, we discuss the prevalence, incidence, risk factors, histological spectrum, diagnosis, pathogenic pathways of DCM, genetic and epigenetic mechanisms involved in DCM, the current treatments, and the beneficial effects of natural product-based therapeutics. Natural treatments range from single doses to continuous regimens lasting weeks or months. Flavonoids are the largest class of natural compounds reported for the treatment of DCM. Natural regimens may cover the way for new treatment strategies for DCM for being multi-target agents in the treatment of DCM, with the ability to play a variety of functions via distinct signaling pathways.

Integrated meta-analysis and network pharmacology analysis: evaluation of Zhigancao decoction as treatment for diabetic cardiomyopathy

Background

Zhigancao Decoction (ZGCD) is derived from "Treatise on Febrile Diseases" and is traditionally prescribed for treating a variety of cardiovascular conditions. As of now, there are no data to support its use as a treatment for diabetic cardiomyopathy (DCM) and the mechanism behind the effect is unclear as well. In the present study, clinical evidence for the efficacy of ZGCD in patients with DCM was examined using a meta-analysis and its underlying anti-DCM molecular mechanisms were explored via network pharmacology.

Methods

The current study utilized an extensive search strategy encompassing various domestic and foreign databases databases to retrieve pertinent articles published up to June 2024. In light of this, a thorough evaluation of the benefits and safety of Zhigancao decoction (ZGCD) was conducted in this study using RevMan and Stata. Subsequently, a number of active compounds and target genes for ZGCD were gathered from the TCMSP and BATMAN-TCM databases, while the main targets for DCM were obtained from databases such as GenCards, OMIM, TTD, and DrugBank. To select core genes, protein-protein interaction networks were generated using the STRING platform, and enrichment analyses were completed using the Metascape platform.

Results

Meta-analysis results were ultimately derived from 9 studies involving 661 patients in total. In comparison with WM therapy alone, the pooled results showed that ZGCD significantly enhanced overall effectiveness. Additionally, the utilization of ZGCD was leading to a reduction in LVEDV, LVESV and LVDD, also a greater increase in LVEF. Meanwhile, the utilization of ZGCD during intervention was more effective in reducing SBP, and DBP. In addition, the ZGCD showed potential in reducing the occurrence of adverse events. In the context of network pharmacology, five constituents of ZGCD-namely lysine, quercetin, gamma-aminobutyric acid, stigmasterol, and beta-sitosterol-are posited to exert anti-diabetic cardiomyopathy (anti-DCM) effects through interactions with the molecular targets ASS1, SERPINE1, CACNA2D1, AVP, APOB, ICAM1, EGFR, TNNC1, F2, F10, IGF1, TNNI2, CAV1, INSR, and INS. The primary mechanisms by which ZGCD may achieve its anti-DCM effects are likely mediated via the AGEs/RAGE signaling pathway, as well as through pathways related to lipid metabolism and atherosclerosis.

Conclusion

In comparison to WM therapy alone, ZGCD demonstrates greater efficacy and safety in the management of DCM. ZGCD not only significantly reduces blood pressure, but also enhances cardiac function while producing fewer adverse effects. The therapeutic effects of ZGCD on DCM can likely be ascribed to its capacity to modulate the AGEs-RAGE signaling pathway, as well as its efficacy in enhancing lipid metabolism and mitigating atherosclerosis.

Systematic Review Registration

identifier (INPLASY202430133).

Assessing intention to use mobile phone-based self-management support among adults with type 2 diabetes in Saudi Arabia: A cross-sectional study

Introduction

The use of mobile phone technology for chronic illness self-management is growing, and it may help people with type 2 diabetes mellitus (T2DM). Innovative methods are needed to improve patient involvement and disease management in the Kingdom of Saudi Arabia due to the high incidence of T2DM.

Objective

The purpose of this study was to explore how the T2DM patients in KSA utilizes their mobile phones for self-management.

Methods

A cross-sectional study was conducted between April and June 2025 among T2DM patients who were attending endocrinologists for their diabetes management in the Northern Border region (Rafha and Arar) and the Central region (Riyadh) in KSA using a validated questionnaire.

Results

This study included a total of 267 participants with T2DM. Nearly all participants (99.3%) possess a cellphone, with 94.8% having daily internet access. The majority of the patients reported to have an intention to use mobile phones and the internet for managing diabetes, with 78.3% for dietary planning, 79.4% for physical activity planning, and 78.7% for text messages as reminders. Factors such as female (p = 0.008), younger age (p = 0.001), and duration of diabetes (p = <0.001) were significantly associated with the intention to use mobile apps for managing their diabetes.

Conclusions

This study demonstrates a significantly higher inclination of participants toward mobile phone technology for diabetes self-management vs. face-to-face consultations. These findings highlight the promising role of mobile phone technology for enhancing diabetes self-management among T2DM patients, thus highlighting the need for targeted interventions.

Role of Quercetin in Diabetic Cardiomyopathy

Diabetic cardiomyopathy is a significant and severe complication of diabetes that affects a large portion of the global population, with its prevalence continuing to rise. Secondary metabolites, including quercetin, have shown promising effects in mitigating the progression of diabetic cardiomyopathy by targeting multiple pathological mechanisms, including impaired insulin signaling, glucotoxicity, lipotoxicity, oxidative stress, inflammation, fibrosis, apoptosis, autophagy, mitochondrial dysfunction, cardiac stiffness, and disrupted calcium handling. Addressing these mechanisms is crucial to prevent left ventricular diastolic and systolic dysfunction in advanced stages of diabetic heart disease. Scientific evidence has highlighted the cardioprotective properties of quercetin at both the myocardial and cellular/molecular levels in diabetic models. Therefore, this review aims to present a comprehensive overview of the proposed mechanisms underlying quercetin's beneficial effects, providing valuable insights that could inform future drug discovery efforts specific to diabetic cardiomyopathy.

Circulating non-coding RNA in type 1 diabetes mellitus as a source of potential biomarkers - An emerging role of sex difference

Non-coding RNAs (ncRNAs), such as microRNA, long non-coding RNA, and circular RNA, are considered essential regulatory molecules mediating many cellular processes. Moreover, an increasing number of studies have investigated the role of ncRNAs in cancers and various metabolic disorders, including diabetes mellitus. Interestingly, some circulating ncRNA detected in body fluids may serve as novel biomarkers. There is still a lack of conventional biomarkers that detect the early stage of type 1 diabetes mellitus. Many circulating microRNA, long non-coding RNA, and circular RNA show aberrant expression in type 1 diabetes patients compared to healthy individuals. However, most studies have focused on circulating microRNA rather than long non-coding RNA or circular RNA. In addition, a few studies have evaluated sex differences in ncRNA biomarkers. Therefore, this article summarises current knowledge about circulating ncRNAs as potential biomarkers for type 1 diabetes and explores the effects of sex on such biomarkers.

Treatment of silicosis with quercetin depolarizing macrophages via inhibition of mitochondrial damage-associated pyroptosis

Macrophage polarization facilitates the inflammatory response and intensified fibrosis in the silicosis microenvironment by a mechanism related to macrophage pyroptosis, although the upstream target remains poorly defined. Currently, there are few reports on the development of drugs that alleviate macrophage polarization by dampening pyroptosis. The present study aims to explore the mechanics of silica mediating macrophage polarization and to investigate whether quercetin (Que) can depolarize macrophages with this mechanism. Silica processing led to prominent M1 polarization of macrophages. Additionally, significant macrophage polarization could be detected in the lung tissue of mice with airway-perfused silica. Further investigation turned out that pronounced mitochondria damage, mtDNA cytoplasmic ectomy, and pyroptosis occurred in response to silica. Nevertheless, Que treatment could effectively attenuate silica-induced mitochondria damage and pyroptosis as demonstrated in vitro and in vivo. Further exploration presented Que could bind to TOM70 and restore silica-induced mitochondrial damage. More importantly, the M1 polarization of macrophage was depressed with the co-treatment of Que and silica, wherein the inflammatory response and pulmonary fibrosis were also mitigated without obvious damage to vital organs. In conclusion, these findings proved that silica leads to mitochondrial damage, thereby evoking pyroptosis and promoting macrophage M1 polarization. Que could bind to TOM70 and restore its function, suppressing mitochondrial damage and pyroptosis, and depolarizing macrophages to reduce fibrosis, which provides a promising strategy for silicosis treatment in the future.

Effective protective mechanisms of HO-1 in diabetic complications: a narrative review

Diabetes mellitus is a metabolic disorder with persistent hyperglycemia caused by a variety of underlying factors. Chronic hyperglycemia can lead to diverse serious consequences and diversified complications, which pose a serious threat to patients. Among the major complications are cardiovascular disease, kidney disease, diabetic foot ulcers, diabetic retinopathy, and neurological disorders. Heme oxygenase 1 (HO-1) is a protective enzyme with antioxidant, anti-inflammatory and anti-apoptotic effects, which has been intensively studied and plays an important role in diabetic complications. By inducing the expression and activity of HO-1, it can enhance the antioxidant, anti-inflammatory, and anti-apoptotic capacity of tissues, and thus reduce the degree of damage in diabetic complications. The present study aims to review the relationship between HO-1 and the pathogenesis of diabetes and its complications. HO-1 is involved in the regulation of macrophage polarization and promotes the M1 state (pro-inflammatory) towards to the M2 state (anti-inflammatory). Induction of HO-1 expression in dendritic cells inhibits them maturation and secretion of pro-inflammatory cytokines and promotes regulatory T cell (Treg cell) responses. The induction of HO-1 can reduce the production of reactive oxygen species, thereby reducing oxidative stress and inflammation. Besides, HO-1 also has an important effect in novel programmed cell death such as pyroptosis and ferroptosis, thereby playing a protective role against diabetes. In conclusion, HO-1 plays a significant role in the occurrence and development of diabetic complications and is closely associated with a variety of complications. HO-1 is anticipated to serve as a novel target for addressing diabetic complications, and it holds promise as a potential therapeutic agent for diabetes and its associated complications. We hope to provide inspiration and ideas for future studies in the mechanism and targets of HO-1 through this review.

The mechanism and promising therapeutic strategy of diabetic cardiomyopathy dysfunctions: Focus on pyroptosis

Diabetes is a major risk factor for cardiovascular diseases, and myocardial damage caused by hyperglycemia is the main cause of heart failure. However, there is still a lack of systematic understanding of myocardial damage caused by diabetes. At present, we believe that the cellular inflammatory damage caused by hyperglycemia is one of the causes of diabetic cardiomyopathy. Pyroptosis, as a proinflammatory form of cell death, is closely related to the occurrence and development of diabetic cardiomyopathy. Therefore, this paper focuses on the important role of inflammation in the occurrence and development of diabetic cardiomyopathy. From the perspective of pyroptosis, we summarize the pyroptosis of different types of cells in diabetic cardiomyopathy and its related signaling pathways. It also summarizes the treatment of diabetic cardiomyopathy, hoping to provide methods for the prevention and treatment of diabetic cardiomyopathy by inhibiting pyroptosis.

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.

Diabetic Cardiomyopathy: Role of Cell Death, Exosomes, Fibrosis and Epicardial Adipose Tissue

Diabetic cardiomyopathy (DCM) represents one of the typical complications associated with diabetes. It has been described as anomalies in heart function and structure, with consequent high morbidity and mortality. DCM development can be described by two stages; the first is characterized by left ventricular hypertrophy and diastolic dysfunction, and the second by heart failure (HF) with systolic dysfunction. The proposed mechanisms involve cardiac inflammation, advanced glycation end products (AGEs) and angiotensin II. Furthermore, different studies have focused their attention on cardiomyocyte death through the different mechanisms of programmed cell death, such as apoptosis, autophagy, necrosis, pyroptosis and ferroptosis. Exosome release, adipose epicardial tissue and aquaporins affect DCM development. This review will focus on the description of the mechanisms involved in DCM progression and development.

Malus toringoides (Rehd.) Hughes decoction alleviates isoproterenol-induced cardiac fibrosis by inhibiting cardiomyocyte inflammation and pyroptosis via the HK1/NLRP3 signaling pathway

Malus toringoides (Rehd.) Hughes, called "Eseye (Ese)," is a traditional medicinal plant from the Tibet province of China that has proven effective in treating cardiac conditions due to its anti-inflammatory, antioxidative, and antiapoptotic properties. In this study, we explored the underlying protective mechanisms of Ese decoction in isoproterenol (ISO)-induced cardiac fibrosis (CF) and established the fact that treatment with an Ese decoction attenuated tissue injury, decreased the release of IL-1β, IL-18, TNF-α, and caspase-3, and elevated the Bax/Bcl-2 ratio in CF mice. We also found that with Ese treatment damage to the mitochondrial ultrastructure of myocardium was alleviated, and the level of reactive oxygen species was markedly diminished. Ese inhibited the expression of proteins associated with pyroptosis by the HK1/NLRP3 signaling pathway and also improved CF. Due to the anti-inflammatory, antioxidative, and antiapoptotic characteristics of Ese decoction, we found that Ese protected against ISO-induced CF, by inhibiting inflammation and pyroptosis as mediated by the HK1/NLRP3 signaling pathway.

A Review on the Natural Products in Treatment of Diabetic Cardiomyopathy (DCM)

Diabetic cardiomyopathy is an insidious and fatal disease, imposing major financial and social burdens on affected individuals. Among the various methods proposed for the treatment of diabetic cardiomyopathy (DCM), treatments with natural products have achieved promising results due to their high efficiency and minimal side-effects. Literature was searched, analyzed, and collected using databases, including PubMed, Web of Science, Excerpt Medica, Science Direct, and Springer. In this study, we reviewed the DCM-related studies on 72 representative natural products. These natural products have been confirmed to be applicable in the therapeutic intervention of DCM, acting through various mechanisms such as the amelioration of metabolic abnormalities, protecting the mitochondrial structure and function, anti-oxidant stress, anti-inflammatory, anti-fibrosis, regulation of Ca 2 + homeostasis and regulation of programmed cell death. The nuclear factor kappa B (NF- κ B), nuclear factor erythroid 2-related factor 2 (Nrf-2), and transforming growth factor- β (TGF- β ) have been extensively studied as high frequency signaling pathways for natural product intervention in DCM. The effectiveness of natural products in treating DCM has been revealed and studied, which provides a reference for DCM-specific drug discovery.

Pyroptosis: Mechanisms and links with diabetic cardiomyopathy

Diabetes mellitus (DM) is a chronic metabolic disease characterized by hyperglycaemia that seriously affects human health. Diabetic cardiomyopathy (DCM) is a major cardiovascular complication and one of the main causes of death in patients with DM. Although DCM attracts great attention, and new therapeutic methods are continuously developed, there is a lack of effective treatment strategies. Therefore, exploring and targeting new signalling pathways related to the evolution of DCM becomes a hotspot and difficulty in the prevention and treatment of DCM. Pyroptosis is a newly discovered regulated cell death that is heavily dependent on the formation of plasma membrane pores by members of the gasdermin protein family and is reported to be involved in the occurrence, development, and pathogenesis of DCM. In this review, we focus on the molecular mechanisms of pyroptosis, its involvement in the relevant signalling pathways of DCM, and potential pyroptosis-targeting therapeutic strategies for the treatment of DCM. Our review provides new insights into the use of pyroptosis as a useful tool for the prevention and treatment of DCM and clarifies future research directions.

Role of pyroptosis in diabetic cardiomyopathy: an updated review

Diabetic cardiomyopathy (DCM), one of the common complications of diabetes, presents as a specific cardiomyopathy with anomalies in the structure and function of the heart. With the increasing prevalence of diabetes, DCM has a high morbidity and mortality worldwide. Recent studies have found that pyroptosis, as a programmed cell death accompanied by an inflammatory response, exacerbates the growth and genesis of DCM. These studies provide a theoretical basis for exploring the potential treatment of DCM. Therefore, this review aims to summarise the possible mechanisms by which pyroptosis promotes the development of DCM as well as the relevant studies targeting pyroptosis for the possible treatment of DCM, focusing on the molecular mechanisms of NLRP3 inflammasome-mediated pyroptosis, different cellular pyroptosis pathways associated with DCM, the effects of pyroptosis occurring in different cells on DCM, and the relevant drugs targeting NLRP3 inflammasome/pyroptosis for the treatment of DCM. This review might provide a fresh perspective and foundation for the development of therapeutic agents for DCM.

Quercetin is a Potential Therapy for Rheumatoid Arthritis via Targeting Caspase-8 Through Ferroptosis and Pyroptosis

Background

Rheumatoid arthritis (RA) is one of the most common chronic inflammatory autoimmune diseases. However, the underlying molecular mechanisms of its pathogenesis are unknown. This study aimed to identify the common biomarkers of ferroptosis and pyroptosis in RA and screen potential drugs.

Methods

The RA-related differentially expressed genes (DEGs) in GSE55235 were screened by R software and intersected with ferroptosis and pyroptosis gene libraries to obtain differentially expressed ferroptosis-related genes (DEFRGs) and differentially expressed pyroptosis-related genes (DEPRGs). We performed Gene Ontology (GO), Kyoto Encyclopedia of the Genome (KEGG), ClueGO, and Protein-Protein Interaction (PPI) analysis for DEFRGs and DEPRGs and validated them by machine learning. The microRNA/transcription factor (TF)-hub genes regulatory network was further constructed. The key gene was validated using the GSE77298 validation set, cellular validation was performed in in vitro experiments, and immune infiltration analysis was performed using CIBERSORT. Network pharmacology was used to find key gene-targeting drugs, followed by molecular docking and molecular dynamics simulations to analyze the binding stability between small-molecule drugs and large-molecule proteins.

Results

Three hub genes (CASP8, PTGS2, and JUN) were screened via bioinformatics, and the key gene (CASP8) was validated and obtained through the validation set, and the diagnostic efficacy was verified to be excellent through the receiver operating characteristic (ROC) curves. The ferroptosis and pyroptosis phenotypes were constructed by fibroblast-like synoviocytes (FLS), and caspase-8 was detected and validated as a common biomarker for ferroptosis and pyroptosis in RA, and quercetin can reduce caspase-8 levels. Quercetin was found to be a potential target drug for caspase-8 by network pharmacology, and the stability of their binding was further verified using molecular docking and molecular dynamics simulations.

Conclusion

Caspase-8 is an important biomarker for ferroptosis and pyroptosis in RA, and quercetin is a potential therapy for RA via targeting caspase-8 through ferroptosis and pyroptosis.

Dexmedetomidine ameliorates diabetic cardiomyopathy by inhibiting ferroptosis through the Nrf2/GPX4 pathway

OBJECTIVE

Dexmedetomidine (DEX) has been shown to have anti-apoptotic effects in diabetes mellitus, but its role in mitigating diabetic cardiomyopathy (DCM) through ferroptosis regulation is unclear.

METHODS

An in vitro DCM model was established using H9C2 cells induced with high glucose (HG) and treated with DEX at varying doses and a nuclear factor erythroid 2-realated factor 2 (Nrf2) specific inhibitor ML385. Cell viability was evaluated using the MTT method after treatment with DEX or mannitol (MAN), and the dosage of DEX used in subsequent experimentation was determined. The effects of HG-induced high osmotic pressure were assessed using MAN as a control. Cell apoptosis was evaluated using flow cytometry. Protein levels of Bcl2, Bax, nuclear Nrf2, and glutathione peroxidase 4 (GPX4) were measured using Western blot. Superoxide dismutase (SOD) activity, malondialdehyde (MDA) levels, Fe²⁺ concentration and reactive oxygen species (ROS) levels were measured using corresponding kits and dichlorodihydrofluorescein diacetate, respectively.

RESULTS

Treatment with DEX or MAN had no effect on H9C2 cell viability. HG induction reduced H9C2 cell viability, increased cell apoptosis, upregulated levels of Bax, Fe²⁺, MDA, and ROS, and downregulated Bcl2 protein levels, SOD activity, and protein levels of nuclear Nrf2 and GPX4. DEX inhibited HG-induced H9C2 cell apoptosis, promoted Nrf2 nuclear translocation, and activated the Nrf2/GPX4 pathway. Inhibition of Nrf2 partially reversed the protective effects of DEX against HG-evoked H9C2 cell injury.

CONCLUSION

Our findings demonstrate that DEX attenuates HG-induced cardiomyocyte injury by inhibiting ferroptosis through the Nrf2/GPX4 pathway, providing potential therapeutic targets for DCM treatment.

Protective effect of quercetin on avermectin induced splenic toxicity in carp: Resistance to inflammatory response and oxidative damage

Avermectin pollution is an important problem that cannot be ignored in aquatic system in recent years. It has brought great trouble to freshwater aquaculture, especially fishery aquaculture. Plant-derived quercetin has anti-inflammatory and antioxidant properties and is widely used as a dietary additive, but its protective effect on immune damage induced by avermectin in freshwater carp remains unclear. This study evaluated the role of dietary additive quercetin supplementation in chronic avermectin exposure of carp spleen. Sixty carp were divided into 4 groups (n = 15/ group), including control group, avermectin treatment group, quercetin treatment group, quercetin and avermectin co-treatment group. Carp were exposed to a 1/10 96 h LC₅₀ dose of avermectin for 30 d and fed a carp diet containing 400 mg/kg quercetin twice a day (3% body weigh/ carp). The results showed that chronic avermectin exposure caused the loose parenchymal structure of carp spleen tissue and the increase of inflammatory cells, accompanied by increased transcription levels of pro-inflammatory il-1β, il-6, tnf-α and decreased levels of anti-inflammatory factors il-10 and tgf-β1, ROS accumulation in spleen tissue. MDA content increased and T-AOC, CAT and GSH levels decreased. Quercetin down-regulates the NF-κB pathway by inhibiting the expression of iNOS and activating p38 MAPK, blocking the transcription of inflammatory factors, and alleviating the inflammation of carp spleen caused by chronic avermectin exposure. In addition, quercetin inhibits the over-activation of Nrf2/Keap-1 signaling axis, blocks ROS accumulation, and restores the spleen REDOX homeostasis. In conclusion, quercetin, as a dietary additive for carp feed, can effectively improve the immune damage caused by avermectin pollution in aquatic environment, resist spleen inflammation and oxidative stress, and provide a theoretical basis for clinical development of freshwater carp feed.

IL‑37 suppresses macrophage ferroptosis to attenuate diabetic atherosclerosis via the NRF2 pathway

IL-37 is a newly discovered inflammatory factor. However, the protective effect and underlying mechanisms of IL-37 on atherosclerosis remain unclear. In the present study, IL-37 was used for intraperitoneal injection in diabetic ApoE^-/- mice caused by streptozotocin. High glucose (HG)/ox-LDL was used to stimulate THP-1 original macrophage followed by IL-37 pretreatment in vitro. The atheromatous plaque area, oxidative stress and inflammation levels in ApoE^-/- mice were evaluated, and the level of macrophage ferroptosis was detected in vivo and in vitro. It was identified that IL-37 treatment significantly decreased plaque area in diabetic ApoE^-/- mice. IL-37 not only improved blood lipid levels in mice, but also reduced serum levels of inflammatory factors including IL-1β and IL-18. Furthermore, IL-37 increased GPX4 and nuclear factor erythroid 2-related factor 2 (NRF2) in the aorta of diabetic mice. In vitro experiment revealed that IL-37 inhibited HG/ox-LDL-induced ferroptosis in macrophages, as evidenced by improved cell membrane oxidation, reduced malondialdehyde production and increased GPX4 expression. Moreover, it was also found that IL-37 enhanced the nuclear translocation of NRF2 in macrophages, while ML385, a specific NRF2 inhibitor, significantly attenuated the protective effect of IL-37 on macrophage ferroptosis caused by HG/ox-LDL. In conclusion, IL-37 suppressed macrophage ferroptosis to attenuate atherosclerosis progression via activating the NRF2 pathway.