Studies on hepatotoxicity and toxicokinetics of colchicine

Novel colchicine ethosomes cataplasm for the treatment of acute gouty arthritis

Gout is a disease caused by the deposition of sodium urate (MSU) crystals in the joints and tissues. Colchicine (COL) has become the first-line drug for the treatment of acute gout due to its low price and efficacy. However, colchicine is highly cytotoxic and oral administration is prone to cause severe adverse effects on the gastrointestinal tract, liver and kidney. Therefore, this study aimed to develop a novel dermal delivery formulation for addressing the safety concerns of this drug. The researchers used ethosomes encapsulation technology to improve the skin permeability of COL. In addition, in order to improve the performance of the ethosomes, it was screened and determined that the addition of 1.0-1.5 mg of ceramide III (Cer3) per mL of ethosomes as a modifier could significantly enhance the stability of the ethosomes, Cer3/COL-ethosomes (CCE) were successfully constructed. The CCE was then mixed with a cataplasm matrix to produce a colchicine-carrying CCE cataplasm, which demonstrated the superimposed effect of the advantages of the two dosage forms, the ethosomes and the cataplasm. Compared with the traditional delivery method of COL, this topical formulation is an attractive alternative for the treatment of gout as it can achieve effective blood levels without causing fluctuations in blood levels, and has good efficacy and higher safety profile.

A systematic study of Pseudobulbus Cremastrae seu Pleiones: Characteristics, Origin, chemical composition and toxicology

ETHNOPHARMACOLOGICAL RELEVANCE

Pseudobulbus Cremastrae seu Pleiones (PCSP) is a multi-source traditional Chinese medicine (TCM) with diverse chemical compositions and toxicity levels. The authenticity identification and safety evaluation of PCSP have attracted widespread attention in clinical applications.

AIM OF THIS STUDY

The objective of this study was to evaluate the authenticity and safety of commercially available PCSP.

MATERIALS AND METHODS

Morphological and microscopic identification, HPLC chromatogram, UPLC-Q-TOF-MS/MS with molecular networking were applied to the authenticity identification of PCSP. The safety of different PCSPs was evaluated by acute toxicity in zebrafish at maximum non-lethal concentration (MNLC) and 10% lethal concentration (LC10). Intestinal toxicity of PCSP was assessed through histological staining, intestinal goblet cells, neutrophils, and intestinal opacity.

RESULTS

Four sources of PCSP varied in size, epidermal longitudinal grooves, and microscopic features. GNPS analysis identified 61, 47, 44, and 56 chemical compounds in Cremastra appendiculate (CA), Oreorchis patens (Lindl.) Lindl. (OPL), Iphigenia indica A. Gray (IIG), and Tulipa edulis (Miq.) Baker (TEB). Colchicine and militarine, were discovered as distinguishing markers. Acute toxicity in zebrafish ranked as follows: IIG > OPL > CA > TEB. Further studies on the intestinal toxicity of the authentic PCSP (CA, OPL) showed that CA induced less damage with a smaller lumen area, fewer neutrophils and goblet cells, and reduced peristalsis inhibition compared to OPL, indicating greater safety.

CONCLUSION

Four different sources of PCSP were accurately distinguished based on three dimensions: character, components, and toxicity. OPL and CA were considered as genuine products, while CA with lower toxicity was more suitable for clinical applications.

A toxicological review of alkaloids

Alkaloids are naturally occurring compounds with complex structures found in natural plants. To further improve the understanding of plant alkaloids, this review focuses on the classification, toxicity and mechanisms of action, providing insight into the occurrence of alkaloid-poisoning events and guiding the safe use of alkaloids in food, supplements and clinical applications. Based on their chemical structure, alkaloids can be divided into organic amines, diterpenoids, pyridines, isoquinolines, indoles, pyrrolidines, steroids, imidazoles and purines. The mechanisms of toxicity of alkaloids, including neurotoxicity, hepatoxicity, nephrotoxicity, cardiotoxicity and cytotoxicity, have also been reviewed. Some cases of alkaloid poisoning have been introduced when used as food or clinically, including accidental food poisoning, excessive consumption, and poisoning caused by the improper use of alkaloids in a clinical setting, and the importance of safety evaluation was illustrated. This review summarizes the toxicity and mechanism of action of alkaloids and provides evidence for the need for the safe use of alkaloids in food, supplements and clinical applications.

Evaluation of the pharmacokinetics, chylomicron inhibition, and toxicity of colchicine in rats given low doses

Colchicine (COL) is known for its ability to inhibit the formation of intestinal chylomicrons and has been utilized as a non-surgical tool to explore drug absorption via the intestinal lymphatics. However, there is limited understanding of its pharmacokinetics and its relationship to effect and toxicity with the doses used. This study aimed to provide comprehensive COL pharmacokinetic data and correlate it with the lymphatic-blocking and toxicological effects of low-doses. Male Sprague-Dawley rats with jugular-vein cannulation (JVC) received 0.1 to 0.5 mg/kg COL via oral, 0.25 mg/kg intraperitoneal, and 0.1 mg/kg intravenous routes, followed by blood and urine sampling for LC-MS/MS analysis. Effects on lipid absorption were assessed in another eight JVC rats receiving peanut oil with and without COL, followed by blood pharmacokinetic and plasma biochemistry analysis. The results revealed that COL exhibited moderate extraction ratio and high volume of distribution, with low oral bioavailability (<8%). About 20 % was recovered in the urine after parenteral dosing. Modest but significant reductions in cholesterol absorption was observed after oral doses of 0.5 mg/kg, accompanied by signs of inflammation and increased liver enzymes persisting for a week. The effect of COL on triglycerides formation was not significant. Despite its use as a non-surgical tool in rats to investigate drug absorption via the lymphatic pathway, COL demonstrated increased levels of liver function enzymes, emphasizing the need for caution and dose optimization in its utilization.

Immunogenic cell death inducers for cancer therapy: An emerging focus on natural products

BACKGROUND

Immunogenic cell death (ICD) is a specific form of regulated cell death induced by a variety of stressors. During ICD, the dying cancer cells release damage-associated molecular patterns (DAMPs), which promote dendritic cell maturation and tumor antigen presentation, subsequently triggering a T-cell-mediated anti-tumor immune response. In recent years, a growing number of studies have demonstrated the potential of natural products to induce ICD and enhance tumor cell immunogenicity. Moreover, there is an increasing interest in identifying new ICD inducers from natural products.

PURPOSE

This study aimed to emphasize the potential of natural products and their derivatives as ICD inducers to promote research on using natural products in cancer therapy and provide ideas for future novel immunotherapies based on ICD induction.

METHOD

This review included a thorough search of the PubMed, Web of Science, Scopus, and Google Scholar databases to identify natural products with ICD-inducing capabilities. A comprehensive search for clinical trials on natural ICD inducers was also conducted using ClinicalTrials.gov, as well as the approved patents using the Espacenet and CNKI Patent Database.

RESULTS

Natural compounds that induce ICD can be categorized into several groups, such as polyphenols, flavonoids, terpenoids, and alkaloids. Natural products can induce the release of DAMPs by triggering endoplasmic reticulum stress, activation of autophagy-related pathways, and reactive oxygen species generation, etc. Ultimately, they activate anti-tumor immune response and improve the efficacy of cancer treatments.

CONCLUSION

A growing number of ICD inducers from natural products with promising anti-cancer potential have been identified. The detailed information presented in this review will contribute to the further development of natural ICD inducers and cancer treatment strategies based on ICD-induced responses.

Colchicine disrupts bile acid metabolic homeostasis by affecting the enterohepatic circulation in mice

Although the medicinal properties of colchicine (COL) have been widely known for centuries, its toxicity has been the subject of controversy. The narrow therapeutic window causes COL to induce gastrointestinal adverse effects even when taken at recommended doses, mainly manifested as nausea, vomiting, and diarrhea. However, the mechanism of COL-induced gastrointestinal toxic reactions remains obscure. In the present study, the mice were dosed with COL (2.5 mg/kg b.w./day) for a week to explore the effect of COL on bile acid metabolism and the mechanism of COL-induced diarrhea. The results showed that COL treatment affected liver biochemistry in mice, resulting in a significant down-regulation of the mRNA expression levels of bile acid biosynthesis regulators Cyp7a1, Cyp8b1, Cyp7b1, and Cyp27a1 in liver tissues. The mRNA expression levels of bile acid transporters Ntcp, Oatp1, Mrp2, Ibabp, Mrp3, Osta, and Ostb in liver and ileum tissues were also significantly down-regulated. In addition, COL treatment significantly inhibited the mRNA expression levels of Fxr and its downstream target genes Shp, Lrh1, and Fgf15 in liver and ileum tissues, affecting the feedback regulation of bile acid biosynthesis. More importantly, the inhibition of COL on bile acid transporters in ileal and hepatic tissues affected bile acid recycling in the ileum as well as their reuptake in the liver, leading to a significantly increased accumulation of bile acids in the colon, which may be an important cause of diarrhea. In conclusion, our study revealed that COL treatment affected bile acid biosynthesis and enterohepatic circulation, thereby disrupting bile acid metabolic homeostasis in mice.

Inhibition of CYP1A1 Alleviates Colchicine-Induced Hepatotoxicity

Colchicine, a natural compound extracted from Colchicum autumnale, is a phytotoxin, but interestingly, it also has multiple pharmacological activities. Clinically, colchicine is widely used for the treatment of gouty arthritis, familial Mediterranean fever, cardiovascular dysfunction and new coronary pneumonia. However, overdose intake of colchicine could cause lethal liver damage, which is a limitation of its application. Therefore, exploring the potential mechanism of colchicine-induced hepatotoxicity is meaningful. Interestingly, it was found that CYP1A1 played an important role in the hepatotoxicity of colchicine, while it might also participate in its metabolism. Inhibition of CYP1A1 could alleviate oxidative stress and pyroptosis in the liver upon colchicine treatment. By regulating CYP1A1 through the CASPASE-1-GSDMD pathway, colchicine-induced liver injury was effectively relieved in a mouse model. In summary, we concluded that CYP1A1 may be a potential target, and the inhibition of CYP1A1 alleviates colchicine-induced liver injury through pyroptosis regulated by the CASPASE-1-GSDMD pathway.

A new insight into mechanism of colchicine poisoning based on untargeted metabolomics

BACKGROUND

Colchicine (COL) is a well-known plant-derived mitogenic toxin that has been widely applied for the treatment of immune system diseases and various cancers. However, its clinical use is severely limited by frequent occurrence of poisoning accidents, and the mechanism of COL poisoning is not clear yet.

PURPOSE

The present study aimed to unveil how COL works as a toxin based on untargeted metabolomics analysis of animal models and clinical human case.

METHODS

KM mice orally administered COL were used to establish poisoning models, and plasma samples were collected for untargeted metabolomics analysis. The data mining was performed to screen dose-dependent differences and disturbed metabolic pathways. The blood samples collected from clinical COL poisoning human case at various time points during treatment period were further analyzed to investigate the temporal changes in the metabolic disposition of COL in vivo and also verify the findings from mice. Finally, the expression of key pathways was evaluated by ELISA and Western blotting analysis.

RESULTS

Histological examination demonstrated systemic toxicity of COL poisoning in mice. Metabolite profiling analysis of plasma samples from model mice and clinical case both revealed that COL poisoning could significantly disturb in vivo metabolism of amino acid and lipid metabolism by the FXR/AMPK signal pathway. Quantitative monitoring of the metabolic process of COL further demonstrated that it could be greatly ameliorated with the rapid metabolic transformation of COL in vivo, which thus may be an effective detoxification pathway for COL poisoning.

CONCLUSION

The findings of the present study provided new insight into the molecular mechanism of COL poisoning, thus helpful for guiding reasonable application of this phytotoxin.

Metabolomics reveals that sulfotransferase 1 may regulate colchicine-induced liver injury

Colchicine is widely used to treat gouty arthritis for years. Previous studies showed that colchicine overdose can cause liver damage, yet the mechanism underlying its hepatotoxicity remains unclear. In this study, hepatotoxicity of colchicine was investigated in vivo. Metabolomic analysis of colchicine metabolites and endogenous metabolites was performed using Ultra High Performance Liquid Chromatography (UHPLC) - mass spectrometry (MS). Seventeen metabolites of colchicine were identified, including 3 novel sulfated metabolites. Meanwhile, endogenous sulfated metabolites were found to be decreased by colchicine. Colchicine might regulate sulfotransferase 1 (SULT1) through perixisome proliferation-activated receptor ɑ (PPARα), and inhibition of SULT1 reduced the levels of sulfated metabolites of colchicine. Inhibition of SULT1 aggravated colchicine-induced liver injury, whereas activation of SULT1 attenuated its liver injury. The supplementation of endogenous sulfated metabolites indoxyl sulfate (IS) or p-cresol sulfate (PCS) alleviated colchicine-induced liver injury through modulation of the CASPASE-1-gasdermin D (GSDMD) pathway. These results indicated that colchicine might cause hepatotoxicity through inhibition of SULT1and decreased production of bioactive sulfated endogenous metabolites IS and PCS. Our results provided evidence for potential therapeutic targets and agents to prevent liver injury caused by colchicine. Targeting the SULT1 enzyme and administration of IS and PCS may be useful in alleviating colchicine hepatotoxicity.

The Dual Therapeutic Potential of Ottelione A on Carbon Tetrachloride-induced Hepatic Toxicity in Mice

BACKGROUND

Some herbal natural products play an important role in protecting organisms from the toxic effect of some xenobiotics. The present study was designed to evaluate the potential therapeutic effects of Ottelione A (OTTE) against carbon tetrachloride(CCl4)-induced toxicity in mice.

METHODS

Adult male Swiss albino mice were divided into six groups: group I was used as a normal control received olive oil; group II received DMSO; group III received OTTE; group IV received CCl4 in olive oil, (injected i.p) 3 times/week for 6 weeks; group V received the same CCl4 regimen as group IV followed by OTTE injected for 15 days, and group VI first received OTTE injected for 15 days followed by the same CCl4 regimen as group IV. Some biochemical and histological parameters were investigated.

RESULTS

Our results showed that the administration of CCl4 caused hepatotoxicity, as monitored by the significant increase in biochemical parameters concerning the olive oil group. Treatment with OTTE appeare d to be effective against hepatotoxic and liver changes induced by CCl4, as evidenced by the improvement of the same parameters.

CONCLUSION

Ottelione A (OTTE) has good antioxidant and therapeutic properties, which can help in preventing CCl4-induced hepatotoxicity in both pre-treatment and post-treatment modes.

Colchicine increases intestinal toxic load by disturbing fecal metabolome homeostasis in mice

Colchicine (COL) has been used to treat gout for over a millennium, but its medicinal use has been controversial due to its potent toxicity in the gastrointestinal tract. Nausea, vomiting, and diarrhea are the most prominent external manifestations of COL gastrointestinal toxicity, but the cause of these adverse events remains obscure. In this study, the mice were exposed to COL (2.5 mg/kg b.w./day) for one week to study the mechanism of COL-induced diarrhea from the perspective of intestinal metabolism. The results showed that COL exposure disturbed intestinal metabolic homeostasis, resulting in a significant accumulation of 116 metabolites and, conversely, significant depletion of 64 metabolites, with the number of differential metabolites being one-eighth of the total metabolites (180/1445). Also, it was found that cAMP, Adenosine 5'-monophosphate, GDP, Inositol, and Cortisol are core metabolites that play crucial roles in COL-induced metabolic disorders. These metabolites could be used as biomarkers to differentiate control and COL-treated groups, implying that these metabolites may be closely related to COL-induced diarrhea. Furthermore, changes in the metabolic pathways (Purine metabolism, biosynthesis and metabolism of aromatic amino acids, and Bile secretion) involved in these five core metabolites increased the toxic load in the gut, which was the culprit leading to intestinal metabolic disorders. In addition, the abnormal bile secretion caused by COL exposure may play an important role in COL-induced diarrhea. In conclusion, our study opens new avenues for understanding the mechanisms of COL-induced gastrointestinal adverse reactions and broadens the scientific horizon on the interactions between COL and host metabolism.

A New Insight into Toxicity of Colchicine Analogues by Molecular Docking Analysis Based on Intestinal Tight Junction Protein ZO-1

Colchicine (COL) is a well-known plant alkaloid long used for medical purposes due to the selective anti-inflammatory effect on acute gouty arthritis. It is also a kind of mitosis toxin with strong inhibitory effects of cell division and is therefore being applied to the treatment of various cancers. However, this product shows a variety of adverse effects that are significantly correlated with the dosage and have attracted much attention. For the first time, the present work obtained a new insight into the gastrointestinal toxicity of colchicine analogues by molecular docking analysis, which was based on the 3D structure of intestinal tight junction protein ZO-1 and the ligand library containing dozens of small-molecule compounds with the basic skeleton of COL and its metabolites. The binding energy and mode of protein–ligand interaction were investigated to better understand the structure–toxicity relationships of COL analogues and the mechanism of action as well. Cluster analysis clearly demonstrated the strong correlation between the binding energy and toxicity of ligand molecules. The interaction mode further revealed that the hydrogen bonding (via the C-7 amide or C-9 carbonyl group) and hydrophobic effect (at ring A or C) were both responsible for ZO-1-related gastrointestinal toxicity of COL analogues, while metabolic transformation via phase I and/or phase II reaction would significantly attenuate the gastrointestinal toxicity of colchicine, indicating an effective detoxication pathway through metabolism.

Cytotoxicity evaluation and metabolism of hepatotoxicity components of Euodiae Fructus in L02 cells

Euodiae Fructus (EF), the dried unripe scented fruit of Euodia rutaecarpa (Juss.) Benth., was reported to show anti-hypertensive, antitumor, and anti-obesity effects. The main alkaloids of EF were reported as the reason for toxicity of EF by metabolic activation majority through CYP3A. Up till the present moment, the cytotoxicity mechanisms of EF have not yet to be fully clarified. For the purposes of this article, the influence of CYP3A inducer and inhibitor on cytotoxicity of EF and metabolism in L02 cells of five alkaloids related to toxicity of EF were evaluated. The results indicated that CYP3A inducer aggravated the toxicity and CYP3A inhibitor alleviated the toxicity. UPLC-Q-Exactive-MS was used for the identification of five alkaloids of EF in L02 cells. A total of 13 metabolites were detected in L02 cells. In general, five alkaloids were widely metabolized in L02 cells such as oxygenation, demethylation, dehydrogenation, and etc. In addition, oxygenation was the main metabolic pathway. It was inferred that the toxicity of EF was closely related to the CYP3A and the metabolic intermediate might be one of the reasons for the toxicity of EF. Hence, the choice of optimal dose might be critical to avoid the adverse reactions owing to combination of EF and CYP3A inducer.

Where Epigenetics Meets Food Intake: Their Interaction in the Development/Severity of Gout and Therapeutic Perspectives

Gout is the most frequent form of inflammatory arthritis in the world. Its prevalence is particularly elevated in specific geographical areas such as in the Oceania/Pacific region and is rising in the US, Europe, and Asia. Gout is a severe and painful disease, in which co-morbidities are responsible for a significant reduction in life expectancy. However, gout patients remain ostracized because the disease is still considered "self-inflicted", as a result of unhealthy lifestyle and excessive food and alcohol intake. While the etiology of gout flares is clearly associated with the presence of monosodium urate (MSU) crystal deposits, several major questions remain unanswered, such as the relationships between diet, hyperuricemia and gout flares or the mechanisms by which urate induces inflammation. Recent advances have identified gene variants associated with gout incidence. Nevertheless, genetic origins of gout combined to diet-related possible uric acid overproduction account for the symptoms in only a minor portion of patients. Hence, additional factors must be at play. Here, we review the impact of epigenetic mechanisms in which nutrients (such as ω-3 polyunsaturated fatty acids) and/or dietary-derived metabolites (like urate) trigger anti/pro-inflammatory responses that may participate in gout pathogenesis and severity. We propose that simple dietary regimens may be beneficial to complement therapeutic management or contribute to the prevention of flares in gout patients.

Toxic plants-Detection of colchicine in a fast systematic clinical toxicology screening using liquid chromatography-mass spectrometry

Colchicum autumnale, which can be mistaken for Allium ursinum, contains the alkaloid colchicine potentially leading to life-threatening up to fatal intoxications. We report two cases of acute intoxications with unexplained circumstances. Using the authors' systematic screening approaches, colchicine could be detected in blood plasma and urine samples using liquid chromatography coupled to linear ion trap mass spectrometry (LC-ITMSⁿ ) and high-resolution tandem mass spectrometry (LC-HRMS/MS). Metabolites of colchicine could be identified in urine for confirmation of screening results. Gas chromatography-mass spectrometry (GC-MS) analysis was also conducted, but colchicine could not be detected. Furthermore, colchicine concentration was estimated via LC-HRMS/MS in plasma samples. Results of the systematic screening indicated the ingestion of colchicine from both subjects. In both cases, the parent compound was detected in blood plasma and urine using the LC-HRMS/MS and LC-ITMSⁿ system. An O-demethylation metabolite was identified in urine samples of both subjects using LC-HRMS/MS; the N-deacetylation product was also found in urine samples of both cases via LC-HRMS/MS and LC-ITMSⁿ . The use of LC-ITMSⁿ resulted only in the detection of the O-demethylation product in case 2. Plasma concentrations were estimated at 2.5 ng/ml and 4.7 ng/ml for cases 1 and 2, respectively. We demonstrated the detection of this highly toxic alkaloid in blood plasma and urine using a time-saving and reliable clinical systematic screening. Furthermore, we identified metabolites of colchicine being rarely discussed in literature, which can be used as additional screening targets.

Development of a lateral-flow ICA strip for the detection of colchicine

Colchicine (COL), which is extracted from colchicine and papaya, is widely used in medicine. However, COL poisoning causes serious adverse complications including death. Therefore, there is a need to develop a sensitive COL detection method. In this study, we developed a highly sensitive monoclonal antibody 1E4 with a half-maximal inhibitory concentration and linear range of 0.43 ng mL^-1 and 0.09-2.16 ng mL^-1, respectively. Using 1E4, we developed a lateral-flow immunochromatographic assay (ICA) strip for COL detection. Based on the results, the detection interval was 1-25 ng mL^-1 in milk, 2.5-50 ng mL^-1 in beef, 1-25 ng mL^-1 in edible lily and 2.5-25 ng mL^-1 in daylily. The lateral-flow ICA strip can be used as an effective tool for COL detection in food samples on site.

Tubulin inhibitory activity of a novel colchicine-binding compounds based on a dinaphthospiropyranran scaffold

Spiropyrans have been investigated for their thermo- and photochromic characteristics, but their biotherapeutic properties have not been addressed. We report anti-proliferative properties of a novel dinaphthospiropyran analogue (1). The compound 1 was synthesized by a simple and expedient method using a one-pot acid-catalyzed aldol condensation of 2-hydroxy-1-naphthaldehyde with 4-piperidone followed by an acetalization reaction. Compound 1 was submitted to anticancer drug screen in the National Cancer Institute's panel of 60 human tumor cell lines. The average concentration of 1 to inhibit 50% cell growth was 5.4 ± 0.23 µM. All cell lines responded at almost the same concentration, suggesting that the action of 1 is not selective for cancer of origin. COMPARE analysis of dose-response data revealed interaction with tubulin as the possible mechanism of action of 1. At molecular level, 1 induced tubulin reorganization in colon cancer HCT-116 cells. Under cell-free conditions, the efficacy of 1 to inhibit tubulin polymerization was comparable to that of paclitaxel and vinblastine. Molecular docking showed that compound 1 binds to the colchicine-binding site of tubulin. We conclude that dinaphthospiropyrans present a novel scaffold for the development of tubulin inhibitors.

Management of Gout-associated MSU crystals-induced NLRP3 inflammasome activation by procyanidin B2: targeting IL-1β and Cathepsin B in macrophages

Gout, the most prevalent inflammatory arthritis worldwide, released interleukin-1β (IL-1β) and Cathepsin B inflammatory mediators that constitute the hallmark of the disease. Herein we aimed to investigate whether procyanidin B2 (PCB2), a natural dietary compound, can suppress MSU crystals-stimulated gouty inflammation. Treated with lipopolysaccharide (LPS) plus MSU, both mouse peritoneal macrophages (MPM) and mouse bone marrow-derived macrophages (BMDM) released a large amount of mature IL-1β compared to those treated with MSU or LPS alone, while IL-1β release was blocked by TLR4 and its downstream effector inhibitors. In two mouse models of gout, oral administration of PCB2 suppressed MSU crystals-induced increasing expression of IL-1β, Cathepsin B and NLRP3 in the air pouch skin and paws, accompanied with the downregulation prostaglandin E2 (PGE2) in pouch exudates. Inflammatory immune cell infiltration including macrophages and neutrophils were significantly blocked by PCB2 in air pouch skin and paws of mice gout groups. PCB2 also suppressed the release of IL-1β and Cathepsin B induced by MSU plus LPS in MPM. Our results suggest that the inhibitory effects of PCB2 on NLRP3 inflammasome may alleviate inflammatory response in gout, and this might be a promising anti-inflammatory mechanism of PCB2 against the inflammation in gout.

Discovery of dihydrofuranoallocolchicinoids - Highly potent antimitotic agents with low acute toxicity

Two series of heterocyclic colchicinoids bearing β-methylenedihydrofuran or 2H-pyran-2-one fragments were synthesized by the intramolecular Heck reaction. Methylenedihydrofuran compounds 9a and 9h were found to be the most cytotoxic among currently known colchicinoids, exhibiting outstanding antiproliferative activity on tumor cell lines in picomolar (0.01-2.1 nM) range of concentrations. Compound 9a potently and substoichiometrically inhibits microtubule formation in vitro, being an order of magnitude more active in this assay than colchicine. Derivatives 9a and 9h revealed relatively low acute toxicity in mice (LD₅₀ ≥ 10 mg/kg i.v.). The X-Ray structure of colchicinoid 9a bound to tubulin confirmed interaction of this compound with the colchicine binding site of tubulin.

Combined Use of Febuxostat and Colchicine Does Not Increase Acute Hepatotoxicity in Patients with Gout: A Retrospective Study

Colchicine has been effectively used to prevent acute flares in patients with gout, but drug-related adverse events have frequently occurred. We investigated whether colchicine therapy with febuxostat is associated with hepatotoxicity in gout patients. Gout patients treated with (n = 121) or without (n = 57) colchicine were enrolled upon initiating febuxostat as a urate-lowering treatment, and clinical and laboratory data at diagnosis were compared. Logistic regression analysis was performed to evaluate the risk factors related to hepatotoxicity. Median age of the with-colchicine and without-colchicine groups was 51.0 (37.0–62.0) and 56.0 (43.5–68.5) years, respectively. During the three months of febuxostat prescription, the prevalence of hepatotoxicity was 13/121 (10.9%) in the with-colchicine group and 4/57 (7.0%) in the without-colchicine group, without statistical significance. The rate of colchicine use was not different between the study subjects with or without hepatotoxicity (76.5% vs. 67.1%, p = 0.587). Pre-existing liver disease was significantly associated with increased risk of hepatotoxicity after febuxostat treatment (odds ratio, 4.083; 95% confidence interval, 1.326–12.577; p = 0.014). Colchicine may be safely used as a prophylactic agent for gout patients with febuxostat. However, upon initiating febuxostat, it is recommended to monitor the development of acute liver injury in gout patients with underlying liver disease.