NLRP3 inflammasome-driven IL-1β and IL-18 contribute to lipopolysaccharide-induced septic cardiomyopathy

Codonopsis pilosula polysaccharide alleviates ulcerative colitis by modulating gut microbiota and SCFA/GPR/NLRP3 pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Codonopsis pilosula (Franch.) Nannf. (CP) is a Chinese herb commonly used in traditional Chinese medicine to treat ulcerative colitis (UC). C. pilosula polysaccharide (CPPS) is an important bioactive compound in CP. Polysaccharides are degraded by and interact with the gut microbiota, exerting therapeutic effects. However, the mechanism of action of CPPS in treating UC by regulating gut microbiota is unclear.

AIM OF THE STUDY

This study aimed to elucidate the therapeutic efficacy of CPPS on UC mice and its mechanism of action.

MATERIALS AND METHODS

Size-exclusion chromatography with multi-angle laser-light scattering and refractive index analysis was employed to ascertain the molecular weight of CPPS, while its monosaccharide composition was determined using ion chromatography. An experimental colitis mouse model was induced by administering 3% (dextran sulfate sodium) DSS in drinking water for five consecutive days. Three doses of CPPS were administered to evaluate their therapeutic effects on UC. CPPS was administered for seven days, and salicylazosulfapyridine was used as a positive control. Inflammatory cytokine secretion in the colon tissue was measured, and histopathological evaluation was performed on colon sections. Alterations in the abundance of the intestinal microbiota species were also analyzed. We then quantified short-chain fatty acids (SCFAs) in the cecal content and verified the G protein-coupled receptor (GPR)/nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) pathways using Western blot. Furthermore, the ameliorative effect of gut microbiota on DSS-induced UC symptoms was verified using the fecal microbiota transplantation (FMT) experiment.

RESULTS

CPPS comprised of rhamnose, arabinose, galactose, glucose, and galacturonic acid. CPPS significantly alleviated DSS-induced UC. Compared to the DSS group, CPPS treatment significantly increased the ratio of the Firmicutes to the Bacteroidetes and upregulated the abundance of beneficial bacteria such as g__Ligilactobacillus, g_Akkermansia, g_Faecalibaculum, g_Odoribacter. The release of acetic acid and butyric acid were further promoted. CPPS can inhibit NLRP3 activation by binding SCFAs to GPR proteins, thereby reducing intestinal inflammation. FMT confirmed that the gut microbiota in the CPPS-trans group sufficiently mitigated DSS-induced UC symptoms.

CONCLUSIONS

CPPS ameliorates the symptoms of DSS-induced UC primarily through the gut microbiota modulation and SCFA/GPR/NLRP3 pathways, making it a promising candidate for UC treatment.

Overview of pyroptosis mechanism and in-depth analysis of cardiomyocyte pyroptosis mediated by NF-κB pathway in heart failure

The pyroptosis of cardiomyocytes has become an essential topic in heart failure research. The abnormal accumulation of these biological factors, including angiotensin II, advanced glycation end products, and various growth factors (such as connective tissue growth factor, vascular endothelial growth factor, transforming growth factor beta, among others), activates the nuclear factor-κB (NF-κB) signaling pathway in cardiovascular diseases, ultimately leading to pyroptosis of cardiomyocytes. Therefore, exploring the underlying molecular biological mechanisms is essential for developing novel drugs and therapeutic strategies. However, our current understanding of the precise regulatory mechanism of this complex signaling pathway in cardiomyocyte pyroptosis is still limited. Given this, this study reviews the milestone discoveries in the field of pyroptosis research since 1986, analyzes in detail the similarities, differences, and interactions between pyroptosis and other cell death modes (such as apoptosis, necroptosis, autophagy, and ferroptosis), and explores the deep connection between pyroptosis and heart failure. At the same time, it depicts in detail the complete pathway of the activation, transmission, and eventual cardiomyocyte pyroptosis of the NF-κB signaling pathway in the process of heart failure. In addition, the study also systematically summarizes various therapeutic approaches that can inhibit NF-κB to reduce cardiomyocyte pyroptosis, including drugs, natural compounds, small molecule inhibitors, gene editing, and other cutting-edge technologies, aiming to provide solid scientific support and new research perspectives for the prevention and treatment of heart failure.

Yeast β-glucan attenuates dextran sulfate sodium-induced colitis: Involvement of gut microbiota and short-chain fatty acids

Yeast β-glucan intervention offers a promising strategy for managing colitis; however, the mechanisms remain unknown. In the present work, the protective effects of yeast β-glucan on DSS-induced colitis in mice was evaluated, focusing on its interaction with gut microbiota. The result showed yeast β-glucan significantly alleviated colitis symptoms, evidenced by reduced weight loss, lower disease activity index (DAI) scores, and minimized intestinal damage. It enhanced intestinal barrier integrity via upregulation of tight junction proteins, suppressed lipopolysaccharide (LPS) release, and decreased pro-inflammatory cytokines production. Additionally, yeast β-glucan boosted short-chain fatty acids (SCFAs) production, and activated their receptors, increased the relative abundances of beneficial microbes like Lactobacillus and Lachnospiraceae_UCG-006. Transcriptomic analyses suggest that yeast β-glucan mitigates inflammation by downregulating gene expression related to IL-17 pathway. Our findings highlight potential of yeast β-glucan as a therapeutic agent for colitis through modulation of gut microbiota and inflammatory responses.

Role of gasdermin D in inflammatory diseases: from mechanism to therapeutics

Inflammatory diseases compromise a clinically common and diverse group of conditions, causing detrimental effects on body functions. Gasdermins (GSDM) are pore-forming proteins, playing pivotal roles in modulating inflammation. Belonging to the GSDM family, gasdermin D (GSDMD) actively mediates the pathogenesis of inflammatory diseases by mechanistically regulating different forms of cell death, particularly pyroptosis, and cytokine release, in an inflammasome-dependent manner. Aberrant activation of GSDMD in different types of cells, such as immune cells, cardiovascular cells, pancreatic cells and hepatocytes, critically contributes to the persistent inflammation in different tissues and organs. The contributory role of GSDMD has been implicated in diabetes mellitus, liver diseases, cardiovascular diseases, neurodegenerative diseases, and inflammatory bowel disease (IBD). Clinically, alterations in GSDMD levels are potentially indicative to the occurrence and severity of diseases. GSDMD inhibition might represent an attractive therapeutic direction to counteract the progression of inflammatory diseases, whereas a number of GSDMD inhibitors have been shown to restrain GSDMD-mediated pyroptosis through different mechanisms. This review discusses the current understanding and future perspectives on the role of GSDMD in the development of inflammatory diseases, as well as the clinical insights of GSDMD alterations, and therapeutic potential of GSDMD inhibitors against inflammatory diseases. Further investigation on the comprehensive role of GSDM shall deepen our understanding towards inflammation, opening up more diagnostic and therapeutic opportunities against inflammatory diseases.

Connecting the Dots: Exploring the Interplay Between Preeclampsia and Peripartum Cardiomyopathy

Preeclampsia and peripartum cardiomyopathy (PPCM) are significant obstetric problems that can arise during or after pregnancy. Both are known to be causes of maternal mortality and morbidity. Several recent studies have suggested a link between preeclampsia and the pathophysiology of PPCM. However, the common thread that connects the two has yet to be thoroughly and fully articulated. Here, we investigate the complex dynamics of preeclampsia and PPCM in this review. Our analysis focuses mainly on inflammatory and immunological responses, endothelial dysfunction as a shared pathway, and potential genetic predisposition to both diseases. To begin, we will look at how excessive inflammatory and immunological responses can lead to clinical symptoms of both illnesses, emphasizing the role of proinflammatory cytokines and immune cells in modifying vascular and tissue responses. Second, we consider endothelial dysfunction to be a crucial point at which endothelial damage and activation contribute to pathogenesis through increased vascular permeability, vascular dysfunction, and thrombus formation. Finally, we examine recent information suggesting genetic predispositions to preeclampsia and PPCM, such as genetic variants in genes involved in the management of blood pressure, the inflammatory response, and heart structural integrity. With this synergistic study, we seek to encourage more research and creative therapy solutions by emphasizing the need for an interdisciplinary approach to understanding and managing the connection between preeclampsia and PPCM.

Epigallocatechin-3-gallate Inhibits LPS/AβO-induced Neuroinflammation in BV2 Cells through Regulating the ROS/TXNIP/NLRP3 Pathway

Neuroinflammation is a key factor in cognitive dysfunction and neurodegenerative diseases such as Alzheimer's disease (AD), so inhibiting neuroinflammation is considered as a potential treatment for AD. Epigallocatechin-3-gallate (EGCG), a polyhydroxyphenol of green tea, has been found to exhibit anti-oxidative, anti-inflammatory and neuroprotective effects. The aim of this study was to investigate the inhibitory effect of EGCG on inflammation and its mechanism. In this study, BV2 cells were simultaneously exposed to lipopolysaccharides (LPS) and the amyloid-β oligomer (AβO) to induce inflammatory microenvironments. Inflammatory cytokines and NLRP3 inflammasome-related molecules were detected by RT-PCR and Western Blot. The results show that EGCG inhibits LPS/AβO-induced inflammation in BV2 cells through regulating IL-1β, IL-6, and TNF-α. Meanwhile, EGCG reduces the activation of the NOD-, LRR-, and pyrin domain-containing protein 3 (NLRP3) inflammasome and levels of intracellular ROS in BV2 cells treated with LPS/AβO by affecting the mitochondrial membrane potential (MMP). Further research found that EGCG inhibited MMP through regulating thioredoxin-interacting protein (TXNIP) in LPS/AβO-induced neuroinflammation. In conclusion, EGCG may alleviate LPS/AβO-induced microglial neuroinflammation by suppressing the ROS/ TXNIP/ NLRP3 pathway. It may provide a potential mechanism underlying the anti-inflammatory properties of EGCG for alleviating AD.

Melatonin: A potential protective multifaceted force for sepsis-induced cardiomyopathy

Sepsis is a life-threatening condition manifested by organ dysfunction caused by a dysregulated host response to infection. Lung, brain, liver, kidney, and heart are among the affected organs. Sepsis-induced cardiomyopathy is a common cause of death among septic patients. Sepsis-induced cardiomyopathy is characterized by an acute and reversible significant decline in biventricular both systolic and diastolic function. This is accompanied by left ventricular dilatation. The pathogenesis underlying sepsis-induced cardiomyopathy is multifactorial. Hence, targeting an individual pathway may not be effective in halting the extensive dysregulated immune response. Despite major advances in sepsis management strategies, no effective pharmacological strategies have been shown to treat or even reverse sepsis-induced cardiomyopathy. Melatonin, namely, N-acetyl-5-methoxytryptamine, is synthesized in the pineal gland of mammals and can also be produced in many cells and tissues. Melatonin has cardioprotective, neuroprotective, and anti-tumor activity. Several literature reviews have explored the role of melatonin in preventing sepsis-induced organ failure. Melatonin was found to act on different pathways that are involved in the pathogenesis of sepsis-induced cardiomyopathy. Through its antimicrobial, anti-inflammatory, and antioxidant activity, it offers a potential role in sepsis-induced cardiomyopathy. Its antioxidant activity is through free radical scavenging against reactive oxygen and nitrogen species and modulating the expression and activity of antioxidant enzymes. Melatonin anti-inflammatory activities control the overactive immune system and mitigate cytokine storm. Also, it mitigates mitochondrial dysfunction, a major mechanism involved in sepsis-induced cardiomyopathy, and thus controls apoptosis. Therefore, this review discusses melatonin as a promising drug for the management of sepsis-induced cardiomyopathy.

Metabolomic Profiling and In Vivo Antiepileptic Effect of Zygophyllum album Aerial Parts and Roots Crude Extracts against Pentylenetetrazole-Induced Kindling in Mice

The chemical profiles of both Zygophyllum album (Z. album) aerial parts and roots extracts were evaluated with LC-ESI-TOF-MS/MS analysis. Twenty-four compounds were detected. Among them, some are detected in both the aerial parts and the roots extracts, and others were detected in the aerial parts only. The detected compounds were mainly flavonoids, phenolic compounds, triterpenes and other miscellaneous compounds. Such compounds contribute to the diverse pharmacological activities elicited by the Z. album species. This study aimed to elucidate the antiepileptic effect of Z. album aerial parts and roots crude extracts against pentylenetetrazole (PTZ)-induced kindling in mice. Male albino mice were divided into four groups, eight animals each. All groups, except the control group, were kindled with PTZ (35 mg/kg i.p.), once every alternate day for a total of 15 injections. One group was left untreated (PTZ group). The remaining two groups were treated prior to PTZ injection with either Z. album aerial parts or roots crude extract (400 mg/kg, orally). Pretreatment with either extract significantly reduced the seizure scores, partially reversed the histological changes in the cerebral cortex and exerted antioxidant/anti-inflammatory efficacy evinced by elevated hippocampal total antioxidant capacity and SOD and catalase activities, parallel to the decrement in MDA content, iNOS activity and the TXNIB/NLRP3 axis with a subsequent decrease in caspase 1 activation and a release of IL-1β and IL-18. Moreover, both Z. album extracts suppressed neuronal apoptosis via upregulating Bcl-2 expression and downregulating that of Bax, indicating their neuroprotective and antiepileptic potential. Importantly, the aerial parts extract elicited much more antiepileptic potential than the roots extract did.

Sodium-glucose cotransporter 2 inhibitor dapagliflozin prevents ejection fraction reduction, reduces myocardial and renal NF-κB expression and systemic pro-inflammatory biomarkers in models of short-term doxorubicin cardiotoxicity

Background

Anthracycline-mediated adverse cardiovascular events are among the leading causes of morbidity and mortality in patients with cancer. Sodium-glucose cotransporter 2 inhibitors (SGLT2i) exert multiple cardiometabolic benefits in patients with/without type 2 diabetes, chronic kidney disease, and heart failure with reduced and preserved ejection fraction. We hypothesized that the SGLT2i dapagliflozin administered before and during doxorubicin (DOXO) therapy could prevent cardiac dysfunction and reduce pro-inflammatory pathways in preclinical models.

Methods

Cardiomyocytes were exposed to DOXO alone or combined with dapagliflozin (DAPA) at 10 and 100 nM for 24 h; cell viability, iATP, and Ca++ were quantified; lipid peroxidation products (malondialdehyde and 4-hydroxy 2-hexenal), NLRP3, MyD88, and cytokines were also analyzed through selective colorimetric and enzyme-linked immunosorbent assay (ELISA) methods. Female C57Bl/6 mice were treated for 10 days with a saline solution or DOXO (2.17 mg/kg), DAPA (10 mg/kg), or DOXO combined with DAPA. Systemic levels of ferroptosis-related biomarkers, galectin-3, high-sensitivity C-reactive protein (hs-CRP), and pro-inflammatory chemokines (IL-1α, IL-1β, IL-2, IL-4, IL-6, IL-10, IL-12, IL17-α, IL-18, IFN-γ, TNF-α, G-CSF, and GM-CSF) were quantified. After treatments, immunohistochemical staining of myocardial and renal p65/NF-kB was performed.

Results

DAPA exerts cytoprotective, antioxidant, and anti-inflammatory properties in human cardiomyocytes exposed to DOXO by reducing iATP and iCa++ levels, lipid peroxidation, NLRP-3, and MyD88 expression. Pro-inflammatory intracellular cytokines were also reduced. In preclinical models, DAPA prevented the reduction of radial and longitudinal strain and ejection fraction after 10 days of treatment with DOXO. A reduced myocardial expression of NLRP-3 and MyD-88 was seen in the DOXO-DAPA group compared to DOXO mice. Systemic levels of IL-1β, IL-6, TNF-α, G-CSF, and GM-CSF were significantly reduced after treatment with DAPA. Serum levels of galectine-3 and hs-CRP were strongly enhanced in the DOXO group; on the other hand, their expression was reduced in the DAPA-DOXO group. Troponin-T, B-type natriuretic peptide (BNP), and N-Terminal Pro-BNP (NT-pro-BNP) were strongly reduced in the DOXO-DAPA group, revealing cardioprotective properties of SGLT2i. Mice treated with DOXO and DAPA exhibited reduced myocardial and renal NF-kB expression.

Conclusion

The overall picture of the study encourages the use of DAPA in the primary prevention of cardiomyopathies induced by anthracyclines in patients with cancer.

Current Perspectives of Mitochondria in Sepsis-Induced Cardiomyopathy

Sepsis-induced cardiomyopathy (SICM) is one of the leading indicators for poor prognosis associated with sepsis. Despite its reversibility, prognosis varies widely among patients. Mitochondria play a key role in cellular energy production by generating adenosine triphosphate (ATP), which is vital for myocardial energy metabolism. Over recent years, mounting evidence suggests that severe sepsis not only triggers mitochondrial structural abnormalities such as apoptosis, incomplete autophagy, and mitophagy in cardiomyocytes but also compromises their function, leading to ATP depletion. This metabolic disruption is recognized as a significant contributor to SICM, yet effective treatment options remain elusive. Sepsis cannot be effectively treated with inotropic drugs in failing myocardium due to excessive inflammatory factors that blunt β-adrenergic receptors. This review will share the recent knowledge on myocardial cell death in sepsis and its molecular mechanisms, focusing on the role of mitochondria as an important metabolic regulator of SICM, and discuss the potential for developing therapies for sepsis-induced myocardial injury.

The role of the NLRP3 inflammasome and pyroptosis in cardiovascular diseases

An intense, stereotyped inflammatory response occurs in response to ischaemic and non-ischaemic injury to the myocardium. The NACHT, LRR and PYD domains-containing protein 3 (NLRP3) inflammasome is a finely regulated macromolecular protein complex that senses the injury and triggers and amplifies the inflammatory response by activation of caspase 1; cleavage of pro-inflammatory cytokines, such as pro-IL-1β and pro-IL-18, to their mature forms; and induction of inflammatory cell death (pyroptosis). Inhibitors of the NLRP3 inflammasome and blockers of IL-1β and IL-18 activity have been shown to reduce injury to the myocardium and pericardium, favour resolution of the inflammation and preserve cardiac function. In this Review, we discuss the components of the NLRP3 inflammasome and how it is formed and activated in various ischaemic and non-ischaemic cardiac pathologies (acute myocardial infarction, cardiac dysfunction and remodelling, atherothrombosis, myocarditis and pericarditis, cardiotoxicity and cardiac sarcoidosis). We also summarize current preclinical and clinical evidence from studies of agents that target the NLRP3 inflammasome and related cytokines.

Atrazine exposure promotes cardiomyocyte pyroptosis to exacerbate cardiotoxicity by activating NF-κB pathway

Atrazine is a ubiquitous herbicide with persistent environmental presence and accumulation in the food chain, posing potential health hazards to organisms. Increasing evidence suggests that atrazine may have detrimental effects on various organ systems, including the nervous, digestive, and immune systems. However, the specific toxicity and underlying mechanism of atrazine-induced cardiac injury remain obscure. In this study, 4-week-old male C57BL/6 mice were administered atrazine via intragastric administration at doses of 50 and 200 mg/kg for 4 and 8 weeks, respectively. Our findings showed that atrazine exposure led to cardiac fibrosis, as evidenced by elevated heart index and histopathological scores, extensive myofiber damage, and interstitial collagen deposition. Moreover, atrazine induced cardiomyocyte apoptosis, macrophage infiltration, and excessive production of inflammatory factors. Importantly, atrazine upregulated the expressions of crucial pyroptosis proteins, including NLRP3, ASC, CASPASE1, and GSDMD, via the activation of NF-κB pathway, thus promoting cardiomyocyte pyroptosis. Collectively, our findings provide novel evidence demonstrating that atrazine may exacerbate myocardial fibrosis by inducing cardiomyocyte pyroptosis, highlighting its potential role in the development of cardiac fibrosis.

Pesticide avermectin-induced hepatotoxicity and growth inhibition in carp: Ameliorative capacity and potential mechanisms of quercetin as a dietary additive

Flavonoid quercetin (QUE) has biological activities of anti-oxidation, anti-inflammation and anti-apoptosis, however, its protective effects against avermectin (AVM) induced liver toxicity in carp remains unclear. The objective of this research is to explore the biologically potent effects of QUE in AVM-induced hepatotoxicity in carp and its underlying mechanism. Therefore, we established a liver injury model in carp induced by AVM to evaluate QUE against AVM induced liver toxicity in carp. In this investigation, AVM dosage was determined as 2.404 μg/L for both groups, and an experimentation of 30 days duration was carried out. Various methods including hematoxylin and eosin (H&E) staining, biochemical kits, real-time quantitative PCR (qRT-PCR), western blotting, TUNEL, reactive oxygen species (ROS) staining, immunofluorescence (Hoseinifar, et al.,), and oil red O staining were used in this study. Results showed that the growth inhibition of carp was relieved in the QUE treatment group comparing to the AVM group. In the QUE treatment group, there was a significant decrease in the levels of ALT and AST in carp liver tissue. Additionally, the histopathological damage and lipid accumulation were alleviated compared to the AVM group. Moreover, QUE prevented AVM induced decrease in the activities of antioxidant enzymes of superoxide dismutase (SOD), glutathione peroxidase (GSH-PX), glutathione (GSH), catalase (CAT) and the accumulation of reactive oxygen species (ROS), but reduced accumulation of malondialdehyde (MDA). In addition, the mRNA levels of liver pro-inflammatory factors of tumor necrosis factor-α (TNF-α), interleukin-1β (iL-1β), interleukin-6 (iL-6), interleukin-10 (iL-10) and the protein levels of NOD-like receptor protein 3 (NLRP3) inflammasome were significantly down-regulated in the QUE treatment group in comparison to the AVM group. We also found that QUE could affect the expression of Bcl2-associated x (Bax), B-cell lymphoma-2 (Bcl-2), cleaved-cysteinyl aspartate specific proteinase (CCaspase3) key apoptotic proteins and TUNEL-labeled apoptotic hepatocytes by regulating SIRT1/FOXO3a signal pathway. In summary, QUE alleviated the growth inhibition, liver oxidative damage, lipid accumulation, inflammatory response, and apoptosis of carp induced by AVM. QUE is a potential protective agent against liver injury induced by AVM in carp.