The role of colchicine in the management of COVID-19: a Meta-analysis

BACKGROUND

The Coronavirus disease 2019 (COVID-19) pandemic has robustly affected the global healthcare and economic systems and it was caused by coronavirus-2 (SARS-CoV-2). The clinical presentation of the disease ranges from a flu-like illness to severe pneumonia and death. Till September 2022, the cumulative number of cases exceeded 600 million worldwide and deaths were more than 6 million. Colchicine is an alkaloid drug that is used in many autoinflammatory conditions e.g., gout, familial Mediterranean fever, and Behçet's syndrome. Colchicine inhibits the production of superoxide and the release of interleukins that stimulate the inflammatory cascade. Colchicine decreases the differentiation of myofibroblast and the release of fibrotic mediators including transforming growth factor (TGF-β1) that are related to the fibrosis. Moreover, colchicine has been used to traet viral myocarditis caused by CMV or EBV, interstitial pneumonia, and pericarditis resulting from influenza B infection. Additionally, colchicine is considered safe and affordable with wide availability.

OBJECTIVE

The aim of the current study was to assess the evidence of colchicine effectiveness in COVID-19 treatment.

METHODS

A comprehensive review of the literature was done till May 2022 and yielded 814 articles after ranking the articles according to authors and year of publication. Only 8 clinical trials and cohort studies fulfilling the inclusion criteria were included for further steps of data collection, analysis, and reporting.

RESULTS

This meta-analysis involved 16,488 patients; 8146 patients in the treatment group and 8342 patients in the control group. The results showed that colchicine resulted in a significant reduction in the mortality rate among patients received colchicine in comparison with placebo or standard care (RR 0.35, 95%CI: 0.15-0.79). Colchicine resulted in a significant decrease in the need for O2 therapy in patients with COVID-19 (RR 0.07, 95%CI 0.02-0.27, P = 0.000024). However, colchicine had no significant effect on the following outcomes among COVID-19 patients: the need for hospitalization, ICU admission, artificial ventilation, and hospital discharge rate. Among the PCR confirmed COVID-19 patients, colchicine decreased the hospitalization rate (RR 0.75, 95%CI 0.57-0.99, P = 0.042). However, colchicine had no effect on mortality and the need for mechanical ventilation among this subgroup.

CONCLUSION

Colchicine caused a significant clinical improvement among COVID-19 patients as compared with the standard care or placebo, in terms of the need for O2, and mortality. This beneficial effect could play a role in the management of COVID-19 especially severe cases to decrease need for oxygen and to decrease mortality among these patients.

Dialysis after kidney transplant failure: how to deal with this daunting task?

The best treatment for patients with end-stage kidney disease is kidney transplantation, which, if successful provides both a reduction in mortality and a better quality of life compared to dialysis. Although there has been significant improvement in short-term outcomes after kidney transplantation, long-term graft survival still remains insufficient. As a result, there has been an increase in the number of individuals who need dialysis again after kidney transplant failure, and increasingly contribute to kidney transplant waiting lists. Starting dialysis after graft failure is a difficult task not only for the patients, but also for the nephrologists and the care team. Furthermore, recommendations for management of dialysis after kidney graft loss are lacking. Aim of this narrative review is to provide a perspective on the role of dialysis in the management of patients with failed kidney allograft. Although numerous studies have reported higher mortality in patients undergoing dialysis following kidney allograft failure, reports are contrasting. A patient-centered, individualized approach should drive the choices of initiating dialysis, dialysis modality, maintenance of immunosuppressive drugs and vascular access.

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.

Effects of TGF-β1 Receptor Inhibitor GW788388 on the Epithelial to Mesenchymal Transition of Peritoneal Mesothelial Cells

We investigated the effectiveness of the transforming growth factor beta-1 (TGF-β) receptor inhibitor GW788388 on the epithelial to mesenchymal transition (EMT) using human peritoneal mesothelial cells (HPMCs) and examined the effectiveness of GW788388 on the peritoneal membrane using a peritoneal fibrosis mouse model. HPMCs were treated with TGF-β with or without GW788388. Animal experiments were conducted on male C57/BL6 mice. Peritoneal fibrosis was induced by intraperitoneal injection of chlorhexidine gluconate. GW788388 was administered by once-daily oral gavage. The morphological change, cell migration, and invasion resulted from TGF-β treatment, but these changes were attenuated by cotreatment with GW788388. TGF-β-treated HPMCs decreased the level of the epithelial cell marker and increased the levels of the mesenchymal cell markers. Cotreatment with GW788388 reversed these changes. Phosphorylated Smad2 and Smad3 protein levels were stimulated with TGF-β and the change was attenuated by cotreatment with GW788388. For the peritoneal fibrosis mice, thickness and collagen deposition of parietal peritoneum was increased, but this change was attenuated by cotreatment with GW788388. GW788388, an orally available potent TGF-β receptor type 1 inhibitor, effectively attenuated TGF-β-induced EMT in HPMCs. Cotreatment with GW788388 improved peritoneal thickness and fibrosis, and recovered peritoneal membrane function in a peritoneal fibrosis mouse model.

Colchicine and myocardial infarction: A review

The inflammatory response is frequent after acute myocardial infarction, and may worsen ischaemia-reperfusion injuries, leading to increased infarct size and poor prognosis. Therefore, inflammation may be a promising therapeutic target, and anti-inflammatory drugs appear to be potential additional treatments in this context. Among these treatments, colchicine-a well-known drug that has been used for centuries in clinical practice for rheumatism-may represent the ideal candidate. Indeed, colchicine exerts direct anti-inflammatory and pleiotropic effects, with potential anti-arrhythmic, anti-fibrotic and anti-atherosclerotic effects, which are particularly interesting in this population of patients. The effects of colchicine in the context of acute myocardial infarction were first studied in preclinical models, with a decrease in inflammation demonstrated in several in vitro and in vivo models. Moreover, a decrease in infarct size and positive effects on haemodynamic variables were also recently demonstrated in a mouse model. Regarding clinical studies, the positive effect of colchicine in stable coronary disease and atherosclerosis was assessed initially. More recently, the value of colchicine in acute myocardial infarction has been studied, showing a positive effect on inflammation and infarct size reduction. Finally, a randomised trial (the COLCOT study) has shown a reduction in outcomes in patients with acute coronary syndrome treated with colchicine.

Encapsulating Peritoneal Sclerosis: Pathophysiology and Current Treatment Options

Encapsulating peritoneal sclerosis (EPS) is a life-threatening complication of long-term peritoneal dialysis (PD), which may even occur after patients have switched to hemodialysis (HD) or undergone kidney transplantation. The incidence of EPS varies across the globe and increases with PD vintage. Causative factors are the chronic exposure to bioincompatible PD solutions, which cause long-term modifications of the peritoneum, a high peritoneal transporter status involving high glucose concentrations, peritonitis episodes, and smoldering peritoneal inflammation. Additional potential causes are predisposing genetic factors and some medications. Clinical symptoms comprise signs of intestinal obstruction and a high peritoneal transporter status with incipient ultrafiltration failure. In radiological, macro-, and microscopic studies, a massively fibrotic and calcified peritoneum enclosed the intestine and parietal wall in such cases. Empirical treatments commonly used are corticosteroids and tamoxifen, which has fibrinolytic properties. Immunosuppressants like azathioprine, mycophenolate mofetil, or mTOR inhibitors may also help with reducing inflammation, fibrin deposition, and collagen synthesis and maturation. In animal studies, N-acetylcysteine, colchicine, rosiglitazone, thalidomide, and renin-angiotensin system (RAS) inhibitors yielded promising results. Surgical treatment has mainly been performed in severe cases of intestinal obstruction, with varying results. Mortality rates are still 25–55% in adults and about 14% in children. To reduce the incidence of EPS and improve the outcome of this devastating complication of chronic PD, vigorous consideration of the risk factors, early diagnosis, and timely discontinuation of PD and therapeutic interventions are mandatory, even though these are merely based on empirical evidence.

Colchicine

Colchicine is an alkaloid which was originally extracted from bulbs of a plant called Colchicum autumnale (meadow saffron). Its active pharmacological component was isolated in 1820 and in 1833 the active ingredient was purified and named colchicine. It consists of three hexameric rings termed A, B, and C. It was first recommended for the treatment of gout by Alexander of Tralles in the sixth century AD. Later it has been employed for suggested and approved indications including primary biliary cirrhosis (PBC), alcohol induced hepatitis, psoriasis, Behçet disease, Sweet syndrome, scleroderma, sarcoidosis and amyloidosis. Perhaps the most effective results have been obtained in the prophylaxis of familial Mediterranean fever (FMF). Colchicine is absorbed in the jejunum and ileum and is trapped in the body tissues. It is metabolized in the liver and the intestine by cytochrome P (CYP) 450 3A4 and P-glycoprotein (PGY) 1. Colchicine is excreted mainly by the biliary system, intestines and the kidneys. It has a narrow therapeutic range, but with normal liver and kidney functions is relatively safe and can be used during pregnancy, nursing and in infants. The main mechanism of action of colchicine is probably through interaction with microtubules affecting leukocyte chemotaxis, thereby suppressing inflammation. The blood level of colchicine may be affected by concomitant drug administration and therefore, caution should be exercised when such medications are added.

Colchicine--Update on mechanisms of action and therapeutic uses

OBJECTIVES

To review the literature and provide an update on the mechanisms of action and therapeutic uses of oral colchicine in arthritis and inflammatory conditions.

METHODS

We performed PubMed database searches through June 2014 for relevant studies in the English literature published since the last update of colchicine in 2008. Searches encompassed colchicine mechanisms of action and clinical applications in medical conditions. A total of 381 articles were reviewed.

RESULTS

The primary mechanism of action of colchicine is tubulin disruption. This leads to subsequent down regulation of multiple inflammatory pathways and modulation of innate immunity. Newly described mechanisms include various inhibitory effects on macrophages including the inhibition of the NACHT-LRRPYD-containing protein 3 (NALP3) inflammasome, inhibition of pore formation activated by purinergic receptors P2X7 and P2X2, and stimulation of dendritic cell maturation and antigen presentation. Colchicine also has anti-fibrotic activities and various effects on endothelial function. The therapeutic use of colchicine has extended beyond gouty arthritis and familial Mediterranean fever, to osteoarthritis, pericarditis, and atherosclerosis.

CONCLUSION

Further understanding of the mechanisms of action underlying the therapeutic efficacy of colchicine will lead to its potential use in a variety of conditions.

Role of tyrosine kinase inhibition with imatinib in an encapsulating peritoneal sclerosis rat model

BACKGROUND

Encapsulating peritoneal sclerosis (EPS) is characterized by neovascularization, increased inflammation, and interstitial fibrosis of the peritoneum. We investigated the effects of imatinib on the peritoneal membrane in an experimental EPS model.

METHODS

We separated 24 non-uremic Wistar rats into four groups: the control group which was injected with 2 mL isotonic saline intraperitoneally (IP) daily for 3 weeks, the CG group which was injected with chlorhexidine gluconate (CG) IP daily for 3 weeks, the resting group which was injected with CG IP between weeks 0-3 followed by a peritoneal rest period between weeks 3-6, and the CG + Imatinib mesylate group (CG + IMA) which received CG through weeks 0-3 followed by 50 mg/kg imatinib mesylate through weeks 3-6. At the end of the study, we performed a 1-h-peritoneal equilibration test and examined the peritoneal function and transforming growth factor-β1 (TGF-β1) in dialysate. Morphologic changes were evaluated by microscopy and immunohistochemistry.

RESULTS

An increased ultrafiltration, dialysate/plasma-creatinine-ratio, end-to-initial-dialysate-glucose-ratio, decreased active mesothelial cell ratio and inflammation, and a slightly decreased TGF-β1 of dialysate were found in the CG + IMA group compared to CG alone. Furthermore, the CG + IMA group had a lower concentration of active mesothelial cells than did the resting group. Ultrafiltration was improved in CG + IMA group compared to resting group, however, significant decrease in peritoneal thickness and inflammation were not found compared to those in resting group. Furthermore, there was no significant difference in fibrosis or TGF-β1-positivity on immunohistochemistry between the groups.

CONCLUSIONS

Tyrosine kinase inhibition with imatinib may lead to a decrease in mesothelial cell activity and an increase in ultrafiltration. However, peritoneal fibrosis was unchanged by imatinib in EPS model.

Update on potential medical treatments for encapsulating peritoneal sclerosis; human and experimental data

Encapsulating peritoneal sclerosis (EPS) is an infrequent but serious complication of peritoneal dialysis (PD). The pathogenesis is unknown but speculation is ongoing. The current management of EPS focuses on prevention and treatment of the inflammatory and fibrotic changes at the level of the peritoneal membrane with immunosuppressive and antifibrotic agents, respectively. This article reviews the currently available human and animal data on potential agents to prevent and/or treat EPS. We propose a strategy for early diagnose EPS in an attempt to avoid the development of the full-blown and potentially life-threatening clinical syndrome of EPS. Future research should focus on studying potential prophylactic and therapeutic agents in humans in large, multicenter, randomized trials but also on early detection of EPS in the inflammatory phase by means of biomarkers and the establishment of a composite EPS score.