Two cases report of febuxostat-induced acute liver injury: acute heart failure as a probable risk factor?

Drug induced liver injury, as a sub-type of hepatotoxicity, is rare but practical problem, producing challenges for clinicians. Within the recent two months, two patients with heart failure develop febuxostat-induced acute liver injury during hospital stay. To the best of our knowledge, very few cases of febuxostat-induced hepatotoxicity have been reported up to now. In this paper, two unusual cases of febuxostat-induced acute liver injury are herein described. The medical history, drug treatment, clinical symptoms, liver function tests, diagnosis and prognosis are fully given in this paper. It should be noticed that, two liver injury happen in patients of heart failure with reduced ejection fraction. Whether heart failure is a risk factor of febuxostat related liver injury, deserves further research. This paper reminds the clinicians that more attention should be paid to the acute liver injury caused by febuxostat, and liver function tests are suggested especially for patients of heart failure.

Network Pharmacology Study on Morus alba L. Leaves: Pivotal Functions of Bioactives on RAS Signaling Pathway and Its Associated Target Proteins against Gout.

M. alba L. is a valuable nutraceutical plant rich in potential bioactive compounds with promising anti-gouty arthritis. Here, we have explored bioactives, signaling pathways, and key proteins underlying the anti-gout activity of M. alba L. leaves for the first-time utilizing network pharmacology. Bioactives in M. alba L. leaves were detected through GC-MS (Gas Chromatography-Mass Spectrum) analysis and filtered by Lipinski's rule. Target proteins connected to the filtered compounds and gout were selected from public databases. The overlapping target proteins between bioactives-interacted target proteins and gout-targeted proteins were identified using a Venn diagram. Bioactives-Proteins interactive networking for gout was analyzed to identify potential ligand-target and visualized the rich factor on the R package via the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway on STRING. Finally, a molecular docking test (MDT) between bioactives and target proteins was analyzed via AutoDock Vina. Gene Set Enrichment Analysis (GSEA) demonstrated that mechanisms of M. alba L. leaves against gout were connected to 17 signaling pathways on 26 compounds. AKT1 (AKT Serine/Threonine Kinase 1), γ-Tocopherol, and RAS signaling pathway were selected as a hub target, a key bioactive, and a hub signaling pathway, respectively. Furthermore, three main compounds (γ-Tocopherol, 4-Dehydroxy-N-(4,5-methylenedioxy-2-nitrobenzylidene) tyramine, and Lanosterol acetate) and three key target proteins-AKT1, PRKCA, and PLA2G2A associated with the RAS signaling pathway were noted for their highest affinity on MDT. The identified three key bioactives in M. alba L. leaves might contribute to recovering gouty condition by inactivating the RAS signaling pathway.

Acute oral colchicine caused gastric mucosal injury and disturbance of associated microbiota in mice.

Colchicine (COL), an ancient and well-known drug, has been used in clinical practice for centuries. On the other hand, COL has also attracted extensive concerns for its potent toxic effects, especially gastrointestinal adverse reactions (nausea, vomiting, and diarrhea) before clinical symptoms relief. In this study, we used a rodent model to study the effects of COL on gastric mucosa and associated microbiota. The mice were exposed to various concentrations of COL (0.1, 0.5, and 2.5 mg kg-1 body weight per day) for 7 days, and the results showed that COL treatment caused severe gastric mucosal damage, accompanied by a significant decrease in gastric mucosal proinflammatory cytokines (IL-1ß, IL-6, and TNF-α). The 16S rRNA gene sequencing revealed that COL significantly perturbed the gastric microbiota composition and reduced the gastric microbiota diversity in mice. Also, we identified bacterial biomarkers associated with diarrhea, including phylum Firmicutes, class Bacilli, order Lactobacillales, family Lactobacillaceae, genu Lactobacillus, and genu Blautia, suggesting that COL-triggered adverse reactions are closely related to gastric microbial perturbations. Our findings open new paths for understanding the mechanism of COL-related adverse gastrointestinal reactions, broadening the scientific view on the interaction between drugs and host gastrointestinal microbiota.

Species and sex differences in the blood clearance and immunogenicity of PEGylated uricase: A comparative 26-week toxicity study in rats and monkeys.

Low response rates and high immunogenicity were observed after repeated injections of pegloticase (Krystexxa) into gout patients during clinical trials. However, related research had not been reported in preclinical animal experiments, which has limited the development of this drug. In this study, the toxicity of mPEG-UHC was studied in rats and monkeys over a 26-week period of repeated intravenous dosing. There were no obvious toxic reactions in the tested animals, with the exception of mPEG-UHC blood clearance and immunogenicity. After repeated injections of mPEG-UHC, rapid loss of uricolytic activity (RLA) was not detected in rats, whereas RLA was observed in 44.4% of drug-treated monkeys. In these monkeys, RLA was observed in 11.1% of males and 77.8% of females, and such incidences increased with higher dosing. High titres of anti-uricase IgG antibodies were associated with RLA but did not result in any toxicity. Remission and recurrence of RLA occurred in one female monkey in the high-dose group because of suppressed and altered immune responses in this animal. The predicted incidence of RLA after repeated injections of mPEG-UHC in gout patients may be lower than that of pegloticase. In this study, the no-observed-adverse-effect levels (NOAELs) of mPEG-UHC in rats and monkeys were 32.0 mg/kg and 20.0 mg/kg, respectively. Therefore, the results showed that rats and monkeys could tolerate long-term and high-dose administrations of mPEG-UHC, and mPEG-UHC blood clearance and immunogenicity showed obvious species and sex differences. These findings will provide valuable information to direct the clinical use of mPEG-UHC.

Colchicine causes prenatal cell toxicity and increases tetraploid risk.

BACKGROUND: Colchicine is a clinical medicine used for relief from gout and familial Mediterranean fever. Because of its toxic effects, intravenous injection of colchicine has been banned, but it is still widely administered orally. We assayed the toxic effects of colchicine in cultured primary chorionic villus cells and amniotic fluid cells to interpret its influence on the placenta and foetus. METHODS: Bright field record and cell count kit 8 were used to value cell viability. Flow cytometer was used to identify cells markers, cell cycle and cell apoptosis. G-banding was used for karyotype analysis for sample genetic and drug effect evaluation. RESULTS: Chorionic villus cells and amniotic fluid cells were characterized as mesenchymal cells that share most cell surface markers and have a similar response to colchicine. Colchicine did not induce a decline in cell viability at low concentrations but suppressed cell proliferation by arresting the cell cycle in the G2/M phase and increased the risk of tetraploid generation in a small subset of cases. CONCLUSIONS: Our study revealed the results of a colchicine-induced toxicity test in prenatal cells and determined the anti-mitotic biologically functional dose and manner of administration that might reduce the risk of tetraploid generation.

Uric acid induced the phenotype transition of vascular endothelial cells via induction of oxidative stress and glycocalyx shedding.

Recent data suggested a causative role of uric acid (UA) in the development of renal disease, in which endothelial dysfunction is regarded as the key mechanism. Endothelial-to-mesenchymal transition (EndoMT) and shedding of the glycocalyx are early changes of endothelial dysfunction. We investigated whether UA induced EndoMT in HUVECs and an animal model of hyperuricemia fed with 2% oxonic acid for 4 wk. UA induced EndoMT in HUVECs with a generation of reactive oxygen species via the activation of membranous NADPH oxidase (from 15 min) and mitochondria (from 6 h) along with glycocalyx shedding (from 6 h), which were blocked by probenecid. GM6001, an inhibitor of matrix metalloproteinase, alleviated UA-induced glycocalyx shedding and EndoMT. Antioxidants including N-acetyl cysteine, apocynin, and mitotempo ameliorated EndoMT; however, they did not change glycocalyx shedding in HUVECs. In the kidney of hyperuricemic rats, endothelial staining in peritubular capillaries (PTCs) was substantially decreased with a de novo expression of α-smooth muscle actin in PTCs. Plasma level of syndecan-1 was increased in hyperuricemic rats, which was ameliorated by allopurinol. UA caused a phenotypic transition of endothelial cells via induction of oxidative stress with glycocalyx shedding, which could be one of the mechanisms of UA-induced endothelial dysfunction and kidney disease.-Ko, J., Kang, H.-J., Kim, D.-A., Kim, M.-J., Ryu, E.-S., Lee, S., Ryu, J.-H., Roncal, C., Johnson, R. J., Kang, D.-H. Uric acid induced the phenotype transition of vascular endothelial cells via induction of oxidative stress and glycocalyx shedding.

Allopurinol-induced toxic epidermal necrolysis featuring almost 60% skin detachment.

RATIONALE: Toxic epidermal necrolysis (TEN) is a life-threatening, immunologically mediated, and usually drug-induced disease. Rarely, clinical pharmacists participating in finding the etiology have been reported. PATIENTS CONCERNS: A 33-year-old male presented to the emergency department with a 1-day history of fever and rash. The patient, being newly diagnosed with gout 10 days ago, received allopurinol at a dose of 250 mg by mouth daily. After 10 days' exposure to allopurinol, the patient manifested with an "influenza-like" prodromal phase (fever of 38°C, throat pains), which was treated with amoxicillin and nonsteroidal anti-inflammatory drugs of the oxicam type. The next day, he developed a worsening fever of 39.5°C, accompanied by a pruriginous rash all over his body. DIAGNOSIS: On physical examination, we observed coalescing dusky red macules over >60% of his body surface area, with blisters and detachment of large sheets of necrolytic epidermis all over his chest and face. The diagnosis of TEN was confirmed. INTERVENTIONS: The patient recovered following treatment with short-term high-dose methylprednisolone sodium succinate, immunoglobulin therapy, topical medication, and supportive therapy. OUTCOMES: He showed a slow but progressive improvement both in symptoms and cutaneous manifestations. Reepithelization of the skin was achieved after 3 weeks. LESSONS: Drug-induced-TEN is potentially fatal. This case underlines the necessity of asking medication history in detail and detecting related drug gene to correctly identify the cause of TEN.

The teratogenicity of allopurinol: A comprehensive review of animal and human studies.

Allopurinol is widely used in the management of multiple disorders including gout, kidney stones and inflammatory bowel disease. Despite of long-term experience, its safety in pregnancy has been debated due to reports on possible teratogenicity. We aimed to review the literature on the safety of allopurinol in pregnancy and offspring. In animals, allopurinol induced species-specific reproductive toxicity. In humans, a total of 53 allopurinol exposed infants were reported in the literature. Major congenital malformations were reported in two cases with a comparable pattern of multiple abnormalities. Five other infants had minor birth defects. In conclusion, the association between allopurinol and teratogenicity appears to be weak and limited to two reports with uncertain causality. However, the available data are insufficient to make a certain judgement, and as allopurinol treatment evolves, report and prospective follow-up of all exposed infants (i.e. deviant and normal cases) should be encouraged.

A 10-years retrospective study on Severe Cutaneous Adverse Reactions (SCARs) in a tertiary hospital in Penang, Malaysia.

INTRODUCTION: Severe cutaneous adverse drug reactions (SCARs) are not uncommon and potentially lifethreatening. Our objective is to study the patient characteristics, the pattern of implicated drugs and treatment outcome among patients with SCARs. METHODS: A 10-year retrospective analysis of SCARs cases in Penang General Hospital was carried out from January 2006 to December 2015. Data collection is based on the Malaysian Adverse Drug Reactions Advisory Committee registry and dermatology clinic records. RESULTS: A total of 189 cases of SCARs were encountered (F:M ratio; 1.2:1.0; mean age of 45 year). The commonest manifestation was Stevens-Johnson Syndrome [SJS] (55.0%), followed by toxic epidermal necrolysis [TEN] (23.8%), drug rash with eosinophilia and systemic symptoms [DRESS] (12.7%), acute generalised exanthematous pustulosis [AGEP] (4.8%), SJS/TEN overlap syndrome (2.6%) and generalised bullous fixed drug eruptions [GBFDE] (1.1%). Mean time to onset for TEN/SJS/Overlap syndrome was 10.5±13 days; AGEP, three days; GBFDE, 2.5±0.7 days, and DRESS, 29.4±5.7 days. The most common drugs implicated were antibiotics (33.3%), followed by allopurinol (18.9%) and anticonvulsant (18.4%). Out of 154 cases of SJS/TEN/overlap syndrome, allopurinol was the commonest causative agents (20.1%). In DRESS, allopurinol accounts for 45.8% of the cases. The mortality rate in SJS, TEN and DRESS were 1.9%, 13.3% and 12.5% respectively. No mortality was observed in AGEP and GBFDE. CONCLUSION: The commonest manifestations of SCARs in our setting were SJS, TEN and DRESS. Allopurinol was the most common culprit. Thus, judicious allopurinol use is advocated and pre-emptive genetic screening for HLAB *5801 should be considered.

Colchicine Increases Ventricular Vulnerability in an Experimental Whole-Heart Model.

The traditional gout medication colchicine has been reported to effectively prevent atrial fibrillation recurrence after atrial fibrillation ablation or cardiac surgery in a few clinical trials. Severe adverse events have not yet been reported. The aim of the present study was to assess possible direct electrophysiological effects in an experimental whole-heart model. Ten rabbit hearts were isolated and Langendorff-perfused. Thereafter, colchicine was administered in two concentrations (1 and 3 µM). Eight endo- and epicardial monophasic action potentials and a 12-lead ECG showed a stable QT interval and action potential duration during colchicine infusion. Furthermore, there was no significant increase in dispersion of repolarization. However, colchicine induced a dose-dependent significant decrease of effective refractory period (ERP; 1 µM: -19 ms, 3 µM: -22 ms; p < 0.05). In the present study, acute infusion of colchicine in isolated rabbit hearts resulted in a reduction of ERP in the presence of a stable myocardial repolarization. This led to a significantly elevated inducibility of ventricular fibrillation. In 4 of 10 hearts, incessant ventricular fibrillation occurred. These results suggest a pro-arrhythmic or toxic effect of colchicine and underline that further clinical studies on potential adverse effects should be conducted before the drug can be recommended for routine use after atrial fibrillation ablation.

Integrative chemical-biological read-across approach for chemical hazard classification.

Traditional read-across approaches typically rely on the chemical similarity principle to predict chemical toxicity; however, the accuracy of such predictions is often inadequate due to the underlying complex mechanisms of toxicity. Here, we report on the development of a hazard classification and visualization method that draws upon both chemical structural similarity and comparisons of biological responses to chemicals measured in multiple short-term assays ("biological" similarity). The Chemical-Biological Read-Across (CBRA) approach infers each compound's toxicity from both chemical and biological analogues whose similarities are determined by the Tanimoto coefficient. Classification accuracy of CBRA was compared to that of classical RA and other methods using chemical descriptors alone or in combination with biological data. Different types of adverse effects (hepatotoxicity, hepatocarcinogenicity, mutagenicity, and acute lethality) were classified using several biological data types (gene expression profiling and cytotoxicity screening). CBRA-based hazard classification exhibited consistently high external classification accuracy and applicability to diverse chemicals. Transparency of the CBRA approach is aided by the use of radial plots that show the relative contribution of analogous chemical and biological neighbors. Identification of both chemical and biological features that give rise to the high accuracy of CBRA-based toxicity prediction facilitates mechanistic interpretation of the models.

Basic measures and systemic medical treatment of patients with toxic epidermal necrolysis.

BACKGROUND: With an incidence of 1.5-1.8/1 million inhabitants per year, toxic epidermal necrolysis is a rare but life threatening disease. It is almost always drug-induced and its lethality is pronounced with up to 50 %. Several therapeutic options are described in literature; however, there is still lack of a universally accepted and specific therapy of toxic epidermal necrolysis. METHODS: This survey considers 8 cases of toxic epidermal necrolysis diagnosed and treated in our clinic from 2003 to 2007. The epidermal sloughing was > 30 % of the body surface in each case. RESULTS: After immediately discontinuing the drug suspected of being responsible for toxic epidermal necrolysis, we treated with systemic corticosteroids in an initial dose of up to 1.5 mg/kg. Moreover, special emphasis was put on basic measures such as control of vital parameters. With this treatment we reached good results; none of the patients died. conclusions: Immediate beginning of therapy is essential for a successful treatment of toxic epidermal necrolysis. Besides systemic therapy with corticosteroids, certain basic measures such as isolation of patients at adequate room temperature to prevent hypothermia, strict control of circulation, temperature and laboratory parameters, daily smears of skin and mucous membranes and a diet rich in calories due to the catabolic metabolic status are very important for successful outcome.

Synthesis and biological activity of pyrazolo[3,4-d]thiazolo[3,2-a]pyrimidin-4-one derivatives: in silico approach.

Xanthine oxidase (XO) is responsible for the pathological condition called gout. Inhibition of XO activity by various pyrazolo[3,4-d]thiazolo[3,2-a]pyrimidine-4-one derivatives was assessed and compared with the standard inhibitor allopurinol. Out of 10 synthesized compounds, two compounds, viz. 3-amino-6-(2-hydroxyphenyl)-1H-pyrazolo[3,4-d]thiazolo[3,2-a]pyrimidin-4-one (3b) and 3-amino-6-(4-chloro-2-hydroxy-5-methylphenyl)-1H-pyrazolo[3,4-d]thiazolo[3,2-a]pyrimidin-4-one (3g) were found to have promising XO inhibitory activity of the same order as allopurinol. Both compounds and allopurinol inhibited competitively with comparable Ki (3b: 3.56 microg, 3g: 2.337 microg, allopurinol: 1.816 microg) and IC(50) (3b: 4.228 microg, 3g: 3.1 microg, allopurinol: 2.9 microg) values. The enzyme-ligand interaction was studied by molecular docking using Autodock in BioMed Cache V. 6.1 software. The results revealed a significant dock score for 3b (-84.976 kcal/mol) and 3g (-90.921 kcal/mol) compared with allopurinol (-55.01 kcal/mol). The physiochemical properties and toxicity of the compounds were determined in silico using online computational tools. Overall, in vitro and in silico study revealed 3-amino-6-(4-chloro-2-hydroxy-5-methylphenyl)-1H-pyrazolo[3,4-d]thiazolo[3,2-a]pyrimidin-4-one (3g) as a potential lead compound for the design and development of XO inhibitors.

Colchicine update: 2008.

OBJECTIVES: To review recent advances in the understanding of molecular mechanisms of drug disposition and cellular mechanisms of action and targets of colchicine, and disease applications and guidelines for oral colchicine use. METHODS: Summarized and interpreted here is the pertinent English and non-English language literature on MEDLINE since the last update of colchicine in this journal in 1998 and published up to July 2008 regarding colchicine pharmacology, toxicology, mechanisms of action, and clinical applications in gout and other medical conditions. RESULTS: Assessment, after review of 1512 publications, is that oral colchicine therapy is being refined by attention to novel targets such as NALP3 and pyrin. The drug has a narrow therapeutic-toxicity window, and potentially serious drug-drug interactions (eg, with clarithromycin and cyclosporine) are better recognized and therefore preventable. Reviewed here are recent advances in colchicine pharmacogenomics, and recognition of drug-drug interactions and predictors of potential toxicities, including alterations in the P-glycoprotein multidrug transporter ABCB1, cytochrome P450 3A4 isoenzyme, and hepatobiliary and renal function. Current understanding of optimization of colchicine dosing is reviewed, as are recent findings on colchicine therapy of nonrheumatic cardiovascular, hepatic, and renal diseases (eg, lowering of C-reactive protein, and treatment of acute and recurrent pericarditis). Finally, the article reviews the recent U.S. Food and Drug Administration-mandated cessation of marketing of injectable colchicine. CONCLUSIONS: Oral colchicine has unique anti-inflammatory and antiproliferative effects with broad ramifications for rheumatic and nonrheumatic disease applications. Significant advances in the last decade have increased understanding of predictors of both colchicine efficacy and toxicity.

Cytotoxicity of colchicine derivatives in primary cultures of human hepatocytes.

BACKGROUND: Colchicine has been used to treat gout for centuries. However, owing to its toxicity it displays a variety of side effects. The replacement of colchicine by less toxic but still active derivatives would solve this drawback. AIM: The aim of this study was to examine the cytotoxicity of 17 colchicine derivatives. METHODS: Primary cultures of human hepatocytes were the model of choice. Prior to testing, we measured the biochemical parameters of liver donors and the toxicological response of the hepatocytes cultures. For toxicity testing, cells were treated for 24 h with tested compounds in concentrations 1-100 microM. We monitored lactate dehydrogenase (LDH) leakage into the medium, mitochondrial activity (MTT test) and secretion of albumin. RESULTS: Our data show that LDH and MTT were less sensitive parameters compared to albumin secretion for monitoring the toxicity of colchicine derivatives. Compounds with lower antimitotic activity displayed lowered toxicity. CONCLUSION: Since human hepatocytes in culture are quiescent cells, they are not as susceptible to tropolone alkaloids as proliferating cells. Screening for colchicine derivatives with lowered cytotoxicity revealed that 10-O-demethylated compounds might be the substances of choice.

[In Medea's gardens--two tales of colchicine]. / In den Gärten der Medea.

Colchicine is a highly active alkaloid used in the treatment of acute inflammatory syndromes such as Mediterranean fever, M. Behçet or gouty arthritis. The two cases we present here illustrate exemplarily the pros and contras of colchicine therapy. In the first case, colchicine was successfully given for recurrent febrile attacks due to acute rheumatic fever. The second patient unfortunately had a fatal colchicine intoxication. The pharmacology of colchicine, the clinical features associated with overdose and the options for treatment are discussed. Colchicine should not be given in combination with macrolides, especially in patients with renal insufficiency.

Micronucleus test in freshwater fish species: an evaluation of its sensitivity for application in field surveys.

Brown trout, Salmo trutta, European eel, Anguilla anguilla, and European minnow, Phoxinus phoxinus, three fish species inhabiting European freshwater ecosystems, were evaluated for their use as in situ pollution biomarkers using the micronucleus test in renal erythrocytes. Experimental exposure (by immersion) to different concentrations of cyclophosphamide, colchicine, and cadmium showed that brown trout are more sensitive to the three compounds than minnows and eels. In situ surveys of wild freshwater ecosystems with different levels of pollution showed that minnows and eels living in polluted sites do not present higher micronuclei averages than those caught in clean rivers systems, whereas micronuclei are induced in brown trout inhabiting polluted sites. Our results demonstrated the suitability of brown trout for in situ biomonitoring of freshwater ecosystems as well as for laboratory tests using the micronucleus test.