Colchicine, a microtubule-disassembling drug, in the therapy of cardiovascular diseases

Innate and adaptive immunity in acute myocarditis

Acute myocarditis is an acute inflammatory cardiomyopathy associated with cardiac damage triggered by a virus or a pathological immune activation. It may present with a wide range of clinical presentations, ranging from mild symptoms to severe forms like fulminant myocarditis, characterized by hemodynamic compromise and cardiogenic shock. The immune system plays a central role in the pathogenesis of myocarditis. In fact, while its function is primarily protective, aberrant responses can be detrimental. In this context, both innate and adaptive immunity play pivotal roles; notably, the innate system offers a non-specific and immediate defense, while the adaptive provides specialized protection with immunological memory. However, dysregulation in these systems can misidentify cardiac tissue, triggering autoimmune reactions and possibly leading to significant cardiac tissue damage. This review highlights the importance of innate and adaptive immune responses in the progression and treatment of acute myocarditis.

Low-Dose Colchicine for the Prevention of Cardiovascular Events After Acute Coronary Syndrome

Colchicine, an established anti-inflammatory drug, is examined for its potential in mitigating adverse cardiovascular events following acute coronary syndrome (ACS). ACS, primarily triggered by plaque rupture and subsequent thrombosis, is a critical cardiovascular condition. Colchicine's mechanism of action involves inhibiting microtubule activity, leading to immobilization of white blood cells and reducing inflammation. Clinical data from studies, including low-dose colchicine for secondary prevention of cardiovascular disease two and colchicine cardiovascular outcomes trial, support its efficacy in reducing major cardiovascular events post-ACS, though some studies report varying results. Colchicine can cause transient gastrointestinal side effects and is prescribed with caution in patients with certain medical conditions. The recent FDA approval of a low dose of colchicine reiterates its benefit in reducing cardiovascular risk. The cost-effectiveness of colchicine products (0.5 and 0.6 mg doses) are compared, suggesting the generic 0.6 mg dose of colchicine to be an alternative to branded forms of the drug.

Colchicine in atrial fibrillation: are old trees in bloom?

Colchicine is a widely used drug that was originally used to treat gout and rheumatic diseases. In recent years, colchicine has shown high potential in the cardiovascular field. Atrial fibrillation (AF) is a cardiovascular disease with a high incidence. One of the most frequent complications following cardiovascular surgery is postoperative atrial fibrillation (POAF), which affects patient health and disease burden. This article reviews the research status of colchicine in AF and summarizes the relevant progress.

Colchicine enhances β adrenoceptor-mediated vasodilation in men with essential hypertension

AIMS

The aim of this study is to examine whether colchicine improves β adrenoceptor-mediated vasodilation in humans by conducting a double-blinded, placebo-controlled intervention study. Colchicine treatment has known beneficial effects on cardiovascular health and reduces the incidence of cardiovascular disease. Studies in isolated rodent arteries have shown that colchicine can enhance β adrenoceptor-mediated vasodilation, but this has not been determined in humans.

METHODS

Middle-aged men with essential hypertension were randomly assigned firstly to acute treatment with either 0.5 mg colchicine (n = 19) or placebo (n = 12). They were subsequently re-randomized for 3 weeks of treatment with either colchicine 0.5 mg twice daily (n = 16) or placebo (n = 15) followed by a washout period of 48-72 h. The vasodilator responses to isoprenaline, acetylcholine and sodium nitroprusside were determined as well as arterial pressure, arterial compliance and plasma inflammatory markers.

RESULTS

Acute colchicine treatment increased isoprenaline (by 38% for the highest dose) as well as sodium nitroprusside (by 29% main effect) -induced vasodilation but had no effect on the response to acetylcholine. The 3-week colchicine treatment followed by a washout period did not induce an accumulated or sustained effect on the β adrenoceptor response, and there was no effect on arterial pressure, arterial compliance or the level of measured inflammatory markers.

CONCLUSION

Colchicine acutely enhances β adrenoceptor- and nitric oxide-mediated changes in vascular conductance in humans, supporting that the mechanism previously demonstrated in rodents, translates to humans. The results provide novel translational evidence for a transient enhancing effect of colchicine on β adrenoceptor-mediated vasodilation in humans with essential hypertension.

CONDENSED ABSTRACT

Preclinical studies in isolated rodent arteries have shown that colchicine can enhance β adrenoceptor-mediated vasodilation. Here we show that this effect of colchicine can be translated to humans. Acute colchicine treatment was found to increase both isoprenaline- and sodium nitroprusside-induced vasodilation. The study provides the first translational evidence for a transient β adrenoceptor-mediated vasodilatory effect of colchicine in humans. The finding of an acute effect suggests that it may be clinically important to maintain an adequate bioavailability of colchicine.

Study on the mechanism of action of colchicine in the treatment of coronary artery disease based on network pharmacology and molecular docking technology

Objective: This is the first study to explore the mechanism of colchicine in treating coronary artery disease using network pharmacology and molecular docking technology, aiming to predict the key targets and main approaches of colchicine in treating coronary artery disease. It is expected to provide new ideas for research on disease mechanism and drug development. Methods: Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP), Swiss Target Prediction and PharmMapper databases were used to obtain drug targets. GeneCards, Online Mendelian Inheritance in Man (OMIM), Therapeutic Target Database (TTD), DrugBank and DisGeNET databases were utilized to gain disease targets. The intersection of the two was taken to access the intersection targets of colchicine for the treatment of coronary artery disease. The Sting database was employed to analyze the protein-protein interaction network. Gene Ontology (GO) functional enrichment analysis was performed using Webgestalt database. Reactom database was applied for Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. Molecular docking was simulated using AutoDock 4.2.6 and PyMOL2.4 software. Results: A total of 70 intersecting targets of colchicine for the treatment of coronary artery disease were obtained, and there were interactions among 50 targets. GO functional enrichment analysis yielded 13 biological processes, 18 cellular components and 16 molecular functions. 549 signaling pathways were obtained by KEGG enrichment analysis. The molecular docking results of key targets were generally good. Conclusion: Colchicine may treat coronary artery disease through targets such as Cytochrome c (CYCS), Myeloperoxidase (MPO) and Histone deacetylase 1 (HDAC1). The mechanism of action may be related to the cellular response to chemical stimulus and p75NTR-mediated negative regulation of cell cycle by SC1, which is valuable for further research exploration. However, this research still needs to be verified by experiments. Future research will explore new drugs for treating coronary artery disease from these targets.

Colchicine in Athero-Thrombosis: Molecular Mechanisms and Clinical Evidence

Several lines of evidence have clearly indicated that inflammation plays a pivotal role in the development of atherosclerosis and of its thrombotic complications such as acute coronary syndromes or ischemic stroke. Thus, it has been postulated that the use of anti-inflammatory agents might be extremely useful to improve cardiovascular outcome. Recently, increasing attention has been reserved to one of the oldest plant-derived drugs still in use in clinical practice, colchicine that has been used as drug to treat inflammatory diseases such gout or Mediterranean fever. To date, current guidelines of the European Society of Cardiology have included colchicine as first line choice for treatment of acute and recurrent pericarditis. Moreover, several studies have investigated its role in the clinical scenarios of cardiovascular disease including chronic and acute coronary syndromes with promising results. In this review, starting from a description of the mechanism(s) involved behind its anti-inflammatory effects, we give an overview on its potential effects in atherothrombosis and finally present an updated overview of clinical evidence on the role of this drug in cardiovascular disease.

Colchicine for prevention of post-operative atrial fibrillation: Meta-analysis of randomized controlled trials

Objective

This study intended to assess the efficacy of colchicine for prevention of post-operative atrial fibrillation (AF).

Background

Post-operative AF is a common complication of surgery operations. Inflammation plays a crucial role in the pathogenesis of post-operative AF. Colchicine, a potent anti-inflammatory drug, may have a role in mitigating the incidence of post-operative AF.

Methods

We searched Cochrane Library, Web of Science, PubMed, China National Knowledge Infrastructure (CNKI), Database of Chinese sci-tech periodicals (COVIP), and Wanfang Database for randomized controlled trials (RCTs) comparing colchicine versus placebo, or usual care for prevention of post-operative AF. The main outcome was the occurrence of AF post operation, which includes cardiac surgery, lung surgery, or pulmonary vein isolation. The estimated risk ratio (RR) for the occurrence of post-operative AF was evaluated using a random-effects model. The safety end point was the development of any side effects.

Results

A total of 12 RCTs with 2274 patients were eventually included in this meta-analysis, where 1141 patients received colchicine and 1133 patients received placebo or usual care. Perioperative colchicine treatment was related to a decreased incidence of post-operative AF (RR: 0.65; 95% confidence interval [CI]: 0.56 to 0.75, p<0.001). Although the incidence of gastrointestinal side effects was increased with colchicine therapy when compared to placebo (RR = 2.49, 95% CI 1.85 to 3.34, p < 0.001), the incidence of major adverse events was not increased (RR = 0.86, 95% CI 0.46 to 1.60, p = 0.64).

Conclusion

In conclusion, the results of our meta-analysis suggest that colchicine treatment could lower the incidence of post-operative AF. Further studies are needed to determine the optimal colchicine treatment regime to minimize the incidence of adverse events.

Therapeutic potential of colchicine in cardiovascular medicine: a pharmacological review

Colchicine is an ancient herbal drug derived from Colchicum autumnale. It was first used to treat familial Mediterranean fever and gout. Based on its unique efficacy as an anti-inflammatory agent, colchicine has been used in the therapy of cardiovascular diseases including coronary artery disease, atherosclerosis, recurrent pericarditis, vascular restenosis, heart failure, and myocardial infarction. More recently, colchicine has also shown therapeutic efficacy in alleviating cardiovascular complications of COVID-19. COLCOT and LoDoCo2 are two milestone clinical trials that confirm the curative effect of long-term administration of colchicine in reducing the incidence of cardiovascular events in patients with coronary artery disease. There is growing interest in studying the anti-inflammatory mechanisms of colchicine. The anti-inflammatory action of colchicine is mediated mainly through inhibiting the assembly of microtubules. At the cellular level, colchicine inhibits the following: (1) endothelial cell dysfunction and inflammation; (2) smooth muscle cell proliferation and migration; (3) macrophage chemotaxis, migration, and adhesion; (4) platelet activation. At the molecular level, colchicine reduces proinflammatory cytokine release and inhibits NF-κB signaling and NLRP3 inflammasome activation. In this review, we summarize the current clinical trials with proven curative effect of colchicine in treating cardiovascular diseases. We also systematically discuss the mechanisms of colchicine action in cardiovascular therapeutics. Altogether, colchicine, a bioactive constituent from an ancient medicinal herb, exerts unique anti-inflammatory effects and prominent cardiovascular actions, and will charter a new page in cardiovascular medicine.

Colchicine for cardiovascular medicine: a systematic review and meta-analysis

Aim: Colchicine, a microtubule-disassembling (antitubulin) agent used for centuries for the treatment of gout and autoimmune diseases, is a drug of growing interest in the cardiovascular field. While in the last decades it has become cornerstone of pericarditis treatment, it has also emerged in the last few years as a promising drug in the management of coronary artery disease, atrial fibrillation and heart failure. This systematic review and meta-analysis aimed to assess the efficacy of colchicine in patients with cardiovascular diseases. Methods: Systematic search in electronic databases (MEDLINE/PubMed, Scopus, BioMed Central, the Cochrane Collaboration Database of Randomized Trials, ClinicalTrials.gov, EMBASE, Google Scholar) was performed to identify randomized controlled trials (RCTs) up to February 2021. Random-effects meta-analysis was performed to assess the risk of cardiovascular events, defined according to clinical setting. Results: Among 15,569 pooled patients from 21 RCTs, colchicine was superior to placebo in the reduction of cardiovascular events. In the setting of pericardial diseases, it was associated with a lower risk of recurrent pericarditis (17 vs 34%, RR = 0.50, 95% CI: 0.42-0.60, I² = 10%). In other studies assessing coronary artery disease patients, colchicine was associated with a reduced risk of major adverse cardiovascular events (MACE) such as myocardial infarction, stroke, cardiovascular death, coronary revascularisation and hospitalization (6.3 vs 9%, RR = 0.67, 95% CI: 0.54-0.84, I² = 55). Among patients with atrial fibrillation, it was associated with lower rates of recurrence (20 vs 30%, RR = 0.68, 95% CI: 0.58-0.81, I² = 0). In the single RCT on heart failure, colchicine was not associated with improved NYHA class. Conclusion: Colchicine is a valuable anti-inflammatory agent for the prevention of cardiovascular events in patients with inflammatory cardiac conditions such as pericardial diseases, coronary artery disease and atrial fibrillation.

Colchicine for Coronary Artery Disease: A Review

Coronary artery disease is a serious threat to human health. More and more evidences indicate chronic inflammatory plays a key role in the development of this disease. Inflammation markers are gradually used in the diagnosis and treatment. Although the treatment of coronary heart disease with colchicine is still controversial, more and more studies showed that patients can benefit from this medicine. In this review, we discuss and summarize colchicine on essential pharmacology, anti-inflammatory mechanism of action, and the most important and recent clinical studies. According to these literatures, colchicine possibly will possibly become a new valuable and cheap medicine for the treatment of coronary artery disease.

Virus-Induced Membrane Fusion in Neurodegenerative Disorders

A growing body of epidemiological and research data has associated neurotropic viruses with accelerated brain aging and increased risk of neurodegenerative disorders. Many viruses replicate optimally in senescent cells, as they offer a hospitable microenvironment with persistently elevated cytosolic calcium, abundant intracellular iron, and low interferon type I. As cell-cell fusion is a major driver of cellular senescence, many viruses have developed the ability to promote this phenotype by forming syncytia. Cell-cell fusion is associated with immunosuppression mediated by phosphatidylserine externalization that enable viruses to evade host defenses. In hosts, virus-induced immune dysfunction and premature cellular senescence may predispose to neurodegenerative disorders. This concept is supported by novel studies that found postinfectious cognitive dysfunction in several viral illnesses, including human immunodeficiency virus-1, herpes simplex virus-1, and SARS-CoV-2. Virus-induced pathological syncytia may provide a unified framework for conceptualizing neuronal cell cycle reentry, aneuploidy, somatic mosaicism, viral spreading of pathological Tau and elimination of viable synapses and neurons by neurotoxic astrocytes and microglia. In this narrative review, we take a closer look at cell-cell fusion and vesicular merger in the pathogenesis of neurodegenerative disorders. We present a "decentralized" information processing model that conceptualizes neurodegeneration as a systemic illness, triggered by cytoskeletal pathology. We also discuss strategies for reversing cell-cell fusion, including, TMEM16F inhibitors, calcium channel blockers, senolytics, and tubulin stabilizing agents. Finally, going beyond neurodegeneration, we examine the potential benefit of harnessing fusion as a therapeutic strategy in regenerative medicine.

Colchicine prevents disease progression in viral myocarditis via modulating the NLRP3 inflammasome in the cardiosplenic axis

Aim

The acute phase of a coxsackievirus 3 (CVB3)‐induced myocarditis involves direct toxic cardiac effects and the systemic activation of the immune system, including the cardiosplenic axis. Consequently, the nucleotide‐binding oligomerization domain‐like receptor pyrin domain‐containing‐3 (NLRP3) inflammasome pathway is activated, which plays a role in disease pathogenesis and progression. The anti‐inflammatory drug colchicine exerts its effects, in part, via reducing NLRP3 activity, and has been shown to improve several cardiac diseases, including acute coronary syndrome and pericarditis. The aim of the present study was to evaluate the potential of colchicine to improve experimental CVB3‐induced myocarditis.

Methods and results

C57BL6/j mice were intraperitoneally injected with 1 × 10⁵ plaque forming units of CVB3. After 24 h, mice were treated with colchicine (5 μmol/kg body weight) or phosphate‐buffered saline (PBS) via oral gavage (p.o.). Seven days post infection, cardiac function was haemodynamically characterized via conductance catheter measurements. Blood, the left ventricle (LV) and spleen were harvested for subsequent analyses. In vitro experiments on LV‐derived fibroblasts (FB) and HL‐1 cells were performed to further evaluate the anti‐(fibro)inflammatory and anti‐apoptotic effects of colchicine via gene expression analysis, Sirius Red assay, and flow cytometry. CVB3 + colchicine mice displayed improved LV function compared with CVB3 + PBS mice, paralleled by a 4.7‐fold (P < 0.01) and 1.7‐fold (P < 0.001) reduction in LV CVB3 gene expression and cardiac troponin‐I levels in the serum, respectively. Evaluation of components of the NLRP3 inflammasome revealed an increased percentage of apoptosis‐associated speck‐like protein containing a CARD domain (ASC)‐expressing, caspase‐1‐expressing, and interleukin‐1β‐expressing cells in the myocardium and in the spleen of CVB3 + PBS vs. control mice, which was reduced in CVB3 + colchicine compared with CVB3 + PBS mice. This was accompanied by 1.4‐fold (P < 0.0001), 1.7‐fold (P < 0.0001), and 1.7‐fold (P < 0.0001) lower numbers of cardiac dendritic cells, natural killer cells, and macrophages, respectively, in CVB3 + colchicine compared with CVB3 + PBS mice. A 1.9‐fold (P < 0.05) and 4.6‐fold (P < 0.001) reduced cardiac gene expression of the fibrotic markers, Col1a1 and lysyl oxidase, respectively, was detected in CVB3 + colchicine mice compared with CVB3 + PBS animals, and reflected by a 2.2‐fold (P < 0.05) decreased Collagen I/III protein ratio. Colchicine further reduced Col3a1 mRNA and collagen protein expression in CVB3‐infected FB and lowered apoptosis and viral progeny release in CVB3‐infected HL‐1 cells. In both CVB3 FB and HL‐1 cells, colchicine down‐regulated the NLRP3 inflammasome‐related components ASC, caspase‐1, and IL‐1β.

Conclusions

Colchicine improves LV function in CVB3‐induced myocarditis, involving a decrease in cardiac and splenic NLRP3 inflammasome activity, without exacerbation of CVB3 load.

Colchicine efficacy and safety for the treatment of cardiovascular diseases

The emerging role of colchicine in the treatment of cardiovascular diseases is a strong demand for a comprehensive understanding of its efficacy and safety. This meta-analysis and systematic review aimed to study the efficacy in the reduction of adverse cardiovascular outcomes (CO), and the risk of colchicine-related adverse events (CRAEs). Fourteen thousand and nine eighty three patients from 22 randomized controlled trials (RCTs) were included, 9 in patients with coronary artery disease-CAD, 9 in patients with pericarditis, 4 in patients with atrial fibrillation-AF or heart failure. Colchicine was efficacious in the reduction of adverse CO across different settings: pericardial diseases (reduced risk of recurrent pericarditis, 17.6% vs. 35%, RR 0.50, 95% CI 0.41-0.61), CAD (reduced risk of cardiac death, myocardial infarction, stroke,coronary revascularization or hospitalization, 6.1% vs. 8.5%, RR 0.73, 95% CI 0.64-0.83), AF (reduced risk of arrhythmia recurrence, 14.2% vs. 22.7%, RR 0.62, 95% CI 0.44-0.88). Colchicine was associated with increased risk of gastrointestinal CRAEs (11.2% vs. 8.8%, RR 1.87, 95% CI 1.41-2.47) and drug discontinuation (5.4% vs. 3.7%, RR 1.58, 95% CI 1.25-1.99). In both cases, the risk was proportional to the daily dose or duration of treatment, possibly due to early drug discontinuation or tolerance. Other CRAEs (muscle-related, liver,hematologic,cutaneous, infections) were not increased by colchicine, as long as all-cause death (2.2% vs. 1.9%, RR 1.11, 95% CI 0.79-1.54) or non-cardiovascular death (1.5% vs. 1%, RR 1.43, 95% CI 0.93-2.19). Colchicine is efficacious and safe for the treatment of cardiovascular diseases. The risk of gastrointestinal CRAEs and drug discontinuation is not significant if colchicine is used at lower doses (0.5 mg daily) or for longer periods of time (> 6 months).

Phytochemical Profiles, Physicochemical Analysis, and Biological Activity of Three Colchicum Species

Background: Colchicum is a genus of the Colchicaceae family with various isolated compounds, especially tropolone alkaloids and flavonoids, which are used for osteoarthritis, gout, cancer, inflammatory diseases, jaundice, and sexual impotence in different societies. Objectives: The current study aimed to evaluate the phytochemical and physicochemical properties and anti-inflammatory activities of three Colchicum species. Methods: Total tropolone alkaloid, total phenolic/total tannin, and total flavonoid contents were determined using acidic potassium dichromate, Folin-Ciocalteu, and aluminum chloride methods, respectively. Moreover, the HPLC method was used for identification and quantitation purposes of tropolone alkaloids. Physicochemical properties of three Colchicum species, including macroscopic and organoleptic properties, solubility, foreign matter, ash values, and heavy metal contents, were evaluated. Besides, in vitro anti-inflammatory activities of the corms also were determined using the protein denaturation technique as a rapid screening method. Results: The highest levels of tropolone alkaloid, phenolic compounds, tannins, and flavonoids were observed in C. autumnale, C. speciosum, and C. robustum, respectively. HPLC analysis indicated the presence of colchicine, demecolcine, 2-demethyl colchicine, 3-demethyl colchicine, colchicoside, colchifoline, cornigerine, and N-deacetyl-N-formyl colchicine in these Colchicum species. The physicochemical properties of C. speciosum and C. robustum corms are appropriate compared to the standard Colchicum autumnale corm. Moreover, all Colchicum species exhibited high anti-inflammatory activities compared to standard drugs. Conclusions: This study demonstrated that the corm of the Colchicum species contained similar main compounds with different amounts, as well as appropriate physicochemical properties. Moreover, the valuable biological effects of these plants stimulate the cultivations on a large scale.

The Role of Colchicine in Atherosclerotic Cardiovascular Disease

Colchicine, an inexpensive immunomodulatory drug used traditionally to treat gout and familial Mediterranean fever, is rapidly accumulating basic and clinical evidence for a therapeutic role in atherosclerotic cardiovascular disease. Its athero-protective properties are thought to be mainly related to its effect on tubulin polymerisation, enabling a broad range of effect on multiple atherosclerotic plaque cell types and cellular processes, including cell division, cell migration as well as pro-inflammatory cytokine and chemokine secretion. These properties indicate the potential to favourably affect all stages of atherosclerotic plaque development including formation, progression, destabilisation, and plaque rupture. This review focusses on the pharmacology of colchicine, the mechanisms by which it modulates atherosclerosis pathobiology, and summarises the current clinical evidence for its use along with the upcoming clinical trial landscape. Given the current lack of primary immunomodulatory drugs in the treatment of atherosclerosis, colchicine is a promising candidate to fill this therapeutic gap.

Anti-inflammatory Therapies for Coronary Heart Disease: A Systematic Review and Meta-Analysis

Background: Anti-inflammatory therapy has been proposed as a promising treatment for coronary heart disease (CHD) that could reduce residual inflammation risk (RIR) and therefore major adverse cardiovascular events. We implemented a systematic review and meta-analysis of randomized controlled trials (RCTs) to assess the clinical benefits of anti-inflammatory agents in patients with CHD based on secondary cardiovascular prevention. Methods: We systemically searched the PubMed, Embase, and Cochrane Library databases for RCTs (published between Jan 1, 1950, and June 1, 2021; no language restrictions) that focused on anti-inflammatory therapy for coronary heart disease. Our primary end points of interest were a composite of all-cause death, recurrent myocardial infarction and stroke. We processed pooled data using a random-effects model. Results: Of 1497 selected studies, 18 studies with 67,449 participants met our inclusion criteria and were included in the present meta-analysis. Comparing anti-inflammatory agents with placebo, there was no significant decrease in risk of primary end points, secondary end points, all-cause mortality, cardiac mortality, recurrent myocardial infarction, stroke or revascularization. Further subgroup analysis indicated that anti-inflammatory agents led to a significant reduction in secondary end points (OR 0.87, CI 0.77-0.99; P = 0.03), recurrent myocardial infarction (OR 0.86, CI 0.78-0.95; P = 0.003) and revascularization (OR 0.81, CI 0.70-0.92; P = 0.001) in patients with stable CHD compared with placebo. Moreover, stable CHD patients had a lower propensity for recurrent myocardial infarction than acute coronary syndrome (ACS) patients when using anti-inflammatory agents (P = 0.03). The colchicine subgroup analysis showed that colchicine yielded a promising reduction in the primary end points (OR 0.81, CI 0.70-0.95; P = 0.009) compared with placebo. Anti-inflammatory agents were associated with a higher risk of infection (OR 1.13, CI 1.03-1.23; P = 0.007) and negligible effects on cancers (OR 0.98, CI 0.90-1.06; P = 0.61). Conclusion: Anti-inflammatory agents appear to have beneficial effects in reducing the risk of recurrent myocardial infarction in patients with stable CHD, albeit at the cost of increased infection. Notably, colchicine demonstrates a promising cardioprotective effect with a lower incidence of major cardiovascular events and thus is a potential therapeutic strategy for stable CHD patients. Systematic Review Registration: PROSPERO, identifier CRD42021245514.

Inflammation May be the Future of Cardiovascular Risk Reduction: Does Colchicine have a Current Indication?

Inflammation as a cardiovascular risk factor has attracted increasing attention . The current standard of care for decreasing the occurrence of cardiovascular events includes controlling risk factors such as hypertension and maximizing the lowering of low-density lipoprotein cholesterol (LDL-C). However, a recent study demonstrated decreased cardiovascular risk with the anti-inflammatory agent canakinumab and created more interest in decreasing cardiovascular risk by decreasing inflammation. Canakinumab is not yet approved and will undoubtedly be very expensive, so interest in an established medication such as colchicine, which is inexpensive to produce, is appropriate if evidence-based benefit is adequately confirmed. Colchicine has existing indications for gout and familial Mediterranean fever and for decreasing the incidence of postpericardiotomy syndrome. If an evidence-based benefit in decreasing cardiovascular risk can be demonstrated for colchicine, it will be of significant importance. Meta-analyses and observational studies have provided evidence to suggest that colchicine decreases cardiovascular risk because of its anti-inflammatory effects. However, randomized controlled trials (RCTs) are needed, and the recently published COLCOT (Colchicine Cardiovascular Outcomes Trial) showed definite benefit on cardiovascular outcomes in adults who had experienced a myocardial infarction within the previous 30 days. Sufficient evidence now supports the use of colchicine for secondary prevention in patients at the highest cardiovascular risk who continue to have cardiovascular events despite good blood pressure control and maximum LDL-C reduction. Nevertheless, more RCTs will be necessary before widespread general use of colchicine in cardiovascular disease prevention can be recommended. The current acquisition cost issues with colchicine also need to be resolved.

Colchicine inhibits the prothrombotic effects of oxLDL in human endothelial cells

BACKGROUND

Tissue Factor (TF) plays a pivotal role in coronary thrombosis. Oxidized low-density lipoproteins (oxLDL) are crucial in development of atherosclerosclerosis. Moreover, oxLDL are known to induce TF expression on several cell types including endothelial cells. The lectin-type oxidized LDL receptor 1 (LOX-1) represent the oxLDL receptor. Colchicine is an anti-mitotic drug recently proven to have beneficial effects in cardiovascular disease via unknown mechanisms. Thus, we aim at investigating colchicine effects on TF expression in oxLDL stimulated human vascular endothelial cells (HUVEC). Some molecular mechanism(s) potentially involved were investigated.

METHODS

HUVEC were pre-incubated with colchicine 10 μM for 1 h and then stimulated with oxLDL (50 μg/mL). TF gene (RT-PCR), protein (western blot), surface expression (FACS) and procoagulant activity (FXa generation assay) were measured. TF translocation to cell surface was investigated by immunofluorescence. NF-κB/IκB axis was examined by western blot analysis and translocation assay. Finally, LOX-1 expression was also investigated.

RESULTS

Colchicine significantly reduced TF gene and protein expression as well as its procoagulant activity in oxLDL-treated HUVEC. These effects seem to be related mainly to action of colchicine on microtubules that, in turn, modulate TF trafficking in the cytoplasm, NF-κB/IκB pathway and LOX-1 expression.

CONCLUSIONS

Data of the present study, although in vitro, indicate that one of the hypothetical mechanisms by which colchicine exert protective cardiovascular effects might be its ability to inhibit the pro-thrombotic activity of oxLDL.

Proteomic Analysis of Myocardia Containing the Obscurin R4344Q Mutation Linked to Hypertrophic Cardiomyopathy

Obscurin is a giant cytoskeletal protein with structural and regulatory roles encoded by the OBSCN gene. Recently, mutations in OBSCN were associated with the development of different forms of cardiomyopathies, including hypertrophic cardiomyopathy (HCM). We previously reported that homozygous mice carrying the HCM-linked R4344Q obscurin mutation develop arrhythmia by 1-year of age under sedentary conditions characterized by increased heart rate, frequent incidents of premature ventricular contractions, and episodes of spontaneous ventricular tachycardia. In an effort to delineate the molecular mechanisms that contribute to the observed arrhythmic phenotype, we subjected protein lysates prepared from left ventricles of 1-year old R4344Q and wild-type mice to comparative proteomics analysis using tandem mass spectrometry; raw data are available via ProteomeXchange with identifier PXD017314. We found that the expression levels of proteins involved in cardiac function and disease, cytoskeletal organization, electropotential regulation, molecular transport and metabolism were significantly altered. Moreover, phospho-proteomic evaluation revealed changes in the phosphorylation profile of Ca²⁺ cycling proteins, including sAnk1.5, a major binding partner of obscurin localized in the sarcoplasmic reticulum; notably, this is the first report indicating that sAnk1 undergoes phosphorylation. Taken together, our findings implicate obscurin in diverse cellular processes within the myocardium, which is consistent with its multiple binding partners, localization in different subcellular compartments, and disease association.

New therapeutic insights into radiation-induced myocardial fibrosis

Radiation therapy (RT) for the treatment of thoracic tumors causes radiation-induced heart disease (RIHD). Radiation-induced myocardial fibrosis (RIMF) is both an acute and chronic stage of RIHD, depending on the specific pathology, and is thought to be a major risk factor for adverse myocardial remodeling and vascular changes. With the use of more three-dimensional conformal radiation regimens and early screenings and diagnoses for RIMF, the incidence of RIHD is declining, but it still must be carefully investigated to minimize the mortality and morbidity of patients with thoracic malignancies after RT treatment. Effective methods for preventing RIMF involve a decrease in the direct radiation dose in the heart, and early screening and diagnosis. Medications remain as a useful adjunct for preventing or treating RIMF. This review mainly discusses the cellular and molecular mechanisms underlying RIMF, and new therapeutic drugs that can potentially be developed from this knowledge.

Colchicine: An Impressive Effect on Posttransplant Capillary Leak Syndrome and Renal Failure

Capillary leak syndrome is a critical condition occasionally occurring posttransplant and is characterized by acute endothelial hyperpermeability leading to systemic protein-rich fluid extravasation and consequent hypovolemia, hypoperfusion, and acute kidney injury. Treatment is merely supportive and is based on osmotic drugs, diuretics, continuous renal replacement therapy, and surgical drainage. However, removal of the underlying inflammatory cause is mandatory to achieve stable resolution. Herein, we report the first successful treatment with colchicine in 2 life-threatening pediatric cases of capillary leak syndrome with renal failure occurring after transplant (heart and bone marrow) and unresponsive to any other line of therapy. Both cases were only palliated by supportive therapy and revealed an impressively rapid response to colchicine both in terms of diuresis and clinical condition recovery, allowing for the cessation of renal replacement therapy in a few hours. In both patients, colchicine was temporarily discontinued for transient leukopenia (attributed to an additive effect with mycophenolate mofetil), resulting in extravasation, and renal failure recurrence was restored only after colchicine reintroduction. Although the association of colchicine with an immunosuppressive drug was formerly contraindicated, no other adverse events were noted when using a minimized dose. Both patients are now maintaining a good renal function without recurrence of extravasation after 6 months of follow-up. In conclusion, this strikingly positive experience forces physicians to consider this old and cost-effective drug as a new, powerful rescue tool in such critical cases.