The development of a targeted and more potent, anti-Inflammatory derivative of colchicine: Implications for gout

A novel zinc ferrite nanoparticle protects against MSU-induced gout arthritis via Nrf2/NF-κB/NLRP3 pathway

AIMS

Gouty arthritis (GA), a prevalent and intricate form of inflammatory arthritis, affects individuals across all age groups. Existing therapeutic agents for GA are associated with substantial adverse effects. The overarching objective of this study is to identify an efficacious and biocompatible intervention strategy for GA.

MATERIALS AND METHODS

In this investigation, we developed a zinc ferrite nanoparticle (ZFN) characterized by outstanding catalytic activities in anti-inflammatory and antioxidative processes, along with negligible biotoxicity. ZFN features low-content Zn2+ doping, which effectively overcomes the issue of low biocompatibility commonly encountered in Zn-based nanoparticles. Both in vitro and in vivo experimental models were utilized to comprehensively evaluate the effects of ZFN.

KEY FINDINGS

The experimental results demonstrate that ZFN exhibits remarkable efficacy in alleviating inflammation and oxidative stress both in vitro and in vivo. It exerts its therapeutic effect on GA by modulating the NF-κB signaling pathway, suppressing the activation of the NLRP3 inflammasome, and activating the Nrf2 pathway.

SIGNIFICANCE

The protective effect of ZFN against GA holds great promise for the clinical translation of biocompatible inorganic nanoplatforms in the treatment of GA. This finding offers a potential alternative to the currently available medications, thereby providing new insights and possibilities for the management of GA.

Metabolomics and anti-inflammatory activity of Commiphora madagascariensis jacq. leaves extract using in vitro and in vivo models

C. madagascariensis, an unexplored species of Burseraceae is used by local population for the management of inflammation and throat pain. The disease alleviation by this plant could be due to the presence of rich repository of active compounds with various pharmacological importances. In this study, therefore, the profiling of metabolites and isolation of active compounds of C. madagascariensis was performed. Furthermore, the ethanol, ethyl acetate extracts and a selected active compound was subjected for in vitro and in vivo anti-inflammatory activities. Metabolomic analysis identified and quantified 116 metabolites from leaves, young stem and gum-resins of C. madagascariensis (Burseraceae) followed by multivariate PCA analysis. NMR, GC-MS and HPLC were used to analyze primary and secondary metabolites. Subsequently, five main isolated compounds were identified as trimethoxy tetrahydrobenzo dioxolo isochromene (TTDI), butyl phenol, butyl propionate phenol, germacrone and β-elemenone. Amongst them, TTDI was found to be a novel compound. Hence, a process was developed to obtain the enriched fraction of TTDI in ethanol and ethyl acetate extracts of leaves. Furthermore, TTDI and extracts were subjected for their in vitro anti-inflammatory activity in LPS sensitized murine splenocytes. The results showed that TTDI and both extracts significantly suppressed the levels of pro-inflammatorycytokines (TNF-α, IFN-γ). Interestingly, the suppression of pro-inflammatory cytokines was evenmore significant by the similar concentration of TTDI when compared with colchicine. However, the level of anti-inflammatory cytokine (IL-10) was found to be unchanged. Additionally, in vivo anti-inflammatory study revealed a significant reduction in carrageenan induced paw edema by TTDI and both the extracts. In the docking study, TTDI was more active than colchicine with strong binding affinity to COX-2, PLA2, and 5β reductase. Our results highlighted that the presence of metabolites with medicinal and nutraceutical importance in C. madagascariensis, could provide opportunities for the development of a new plant-based therapeutics for inflammation.

Intestinal toxicity alleviation and efficacy potentiation through therapeutic administration of Lactobacillus paracasei GY-1 in the treatment of gout flares with colchicine

Gout flares have emerged as a significant public health concern. Colchicine (COL) is a first-line and standard drug for treating gout flares. However, its clinical use is limited due to various adverse effects. Besides, COL fails to adequately meet the needs of patients, particularly young patients. In this study, we investigate the therapeutic administration of Lactobacillus paracasei GY-1 (GY-1) to overcome the limitations of COL. Our results demonstrate that GY-1 attenuates COL toxicity in terms of body weight loss, decreased feed intake, mortality, reduced locomotor activity, colon shortening, increased oxidative stress, histological damage, and impaired gut permeability. Meanwhile, we demonstrate that GY-1 enhances the therapeutic effect for gout flares when combined with COL, as evidenced by the reduction in paw swelling, decreased levels of proinflammatory cytokines including IL-1β and TNF-α, and an increase in the anti-inflammatory cytokine IL-10. Additionally, the absolute quantification of the gut microbiota shows that GY-1 restores the gut microbiota imbalance caused by COL. Furthermore, GY-1 reduces the abundance of 4 Alistipes species and 6 Porphyromonadaceae species, which may be responsible for toxicity alleviation. At the same time, GY-1 increases the abundance of Bacteroides sartorii and Enterococcus sp., which may contribute to its therapeutic efficacy. This study demonstrates the feasibility of developing probiotic-based adjuvant therapy or bacteriotherapy for treating gout flares. To our knowledge, GY-1 is the first probiotic that could be used as an alternative synergetic agent with COL for the therapeutic treatment of gout flares.

Rapidly separating dissolving microneedles with sustained-release colchicine and stabilized uricase for simplified long-term gout management

Despite growing prevalence and incidence, the management of gout remains suboptimal. The intermittent nature of the gout makes the long-term urate-lowering therapy (ULT) particularly important for gout management. However, patients are reluctant to take medication day after day to manage incurable occasional gout flares, and suffer from possible long-term toxicity. Therefore, a safe and easy-to-operate drug delivery system with simple preparation for the long-term management of gout is very necessary. Here, a chitosan-containing sustained-release microneedle system co-loaded with colchicine and uricase liposomes were fabricated to achieve this goal. This microneedle system was confirmed to successfully deliver the drug to the skin and maintain a one-week drug retention. Furthermore, its powerful therapeutic potency to manage gout was investigated in both acute gouty and chronic gouty models. Besides, the drug co-delivery system could help avoid long-term daily oral colchicine, a drug with a narrow therapeutic index. This system also avoids mass injection of uricase by improving its stability, enhancing the clinical application value of uricase. In general, this two-drug system reduces the dosage of uricase and colchicine and improves the patient's compliance, which has a strong clinical translation.

Interaction of Colchicine-Site Ligands With the Blood Cell-Specific Isotype of β-Tubulin—Notable Affinity for Benzimidazoles

Tubulin, the main component of microtubules, is an α-β heterodimer that contains one of multiple isotypes of each monomer. Although the isotypes of each monomer are very similar, the beta tubulin isotype found in blood cells is significantly divergent in amino acid sequence compared to other beta tubulins. This isotype, beta class VI, coded by human gene TUBB1, is found in hematologic cells and is recognized as playing a role in platelet biogenesis and function. Tubulin from the erythrocytes of the chicken Gallus gallus contains almost exclusively βVI tubulin. This form of tubulin has been reported to differ from brain tubulin in binding of colchicine-site ligands, previously thought to be a ubiquitous characteristic of tubulin from higher eukaryotes. In this study, we sought to gain a better understanding of the structure-activity relationship of the colchicine site of this divergent isotype, using chicken erythrocyte tubulin (CeTb) as the model. We developed a fluorescence-based assay to detect binding of drugs to the colchicine site and used it to study the interaction of 53 colchicine-site ligands with CeTb. Among the ligands known to bind at this site, most colchicine derivatives had lower affinity for CeTb compared to brain tubulin. Remarkably, many of the benzimidazole class of ligands shows increased affinity for CeTb compared to brain tubulin. Because the colchicine site of human βVI tubulin is very similar to that of chicken βVI tubulin, these results may have relevance to the effect of anti-cancer agents on hematologic tissues in humans.

Technologies for Solubility, Dissolution and Permeation Enhancement of Natural Compounds

The current review is based on the advancements in the field of natural therapeutic agents which could be utilized for a variety of biomedical applications and against various diseases and ailments. In addition, several obstacles have to be circumvented to achieve the desired therapeutic effectiveness, among which limited dissolution and/or solubility and permeability are included. To counteract these issues, several advancements in the field of natural therapeutic substances needed to be addressed. Therefore, in this review, the possible techniques for the dissolution/solubility and permeability improvements have been addressed which could enhance the dissolution and permeability up to several times. In addition, the conventional and modern isolation and purification techniques have been emphasized to achieve the isolation and purification of single or multiple therapeutic constituents with convenience and smarter approaches. Moreover, a brief overview of advanced natural compounds with multiple therapeutic effectiveness have also been anticipated. In brief, enough advancements have been carried out to achieve safe, effective and economic use of natural medicinal agents with improved stability, handling and storage.

Comparison of Neutrophil Function in Granulocyte Concentrates From Prednisone- and G-CSF-Treated Donors: Effect of Stimulant, Leukapheresis and Storage

Transfusion of granulocyte concentrates (GC) is an alternative therapy for neutropenic patients with life-threatening infections. While neutrophils are the main source of antimicrobial activity, only neutrophil numbers are used to certify GCs. The objective of this study was thus to functionally characterize neutrophils in GCs prepared by leukapheresis from G-CSF-stimulated donors and compare to the less characterized prednisone GCs. GCs prepared from healthy donors stimulated with prednisone and then G-CSF after a 6-month washout period were analyzed prior to and after leukapheresis, and after storage. Leukocyte composition, neutrophil viability, calcium mobilization, chemotaxis, phagocytosis, reactive oxygen species, cytokine production and metabolites were determined. G-CSF GCs contained significantly more neutrophils than prednisone GCs of which 40% were immature. In comparison to non-stimulated healthy donor neutrophils, prednisone GC neutrophils exhibited enhanced phagocytosis and G-CSF GC neutrophils showed decreased chemotaxis but increased IL-8 production. Leukapheresis altered prednisone GC neutrophil responses. Storage had a significant, negative impact on G-CSF GC neutrophils compared to prednisone GC neutrophils. G-CSF and prednisone GC neutrophils thus differ in maturity and function, and G-CSF GC neutrophils are more sensitive to storage. Functional testing of GC neutrophils and better storage conditions would improve the quality of this blood product.

Design and synthesis of adamantyl-substituted flavonoid derivatives as anti-inflammatory Nur77 modulators: Compound B7 targets Nur77 and improves LPS-induced inflammation in vitro and in vivo

In continuing our study on discovering new Nur77-targeting anti-inflammatory agents with natural skeletons, we combined adamantyl group and hydroxamic acid moiety with flavonoid nucleus, synthesized three series of flavonoid derivatives with a similar structure like CD437, and evaluated their activities against LPS-induced inflammation. Compound B7 was found to be an excellent Nur77 binder (K_d = 3.55 × 10^-7 M) and a potent inhibitor of inflammation, which significantly decreased the production of cytokines in vitro, such as NO, IL-6, IL-1β, and TNF-α, at concentrations of 1.25, 2.5, and 5 μM. Mechanistically, B7 modulated the colocalization of Nur77 at mitochondria and inhibited the lipopolysaccharides (LPS)-induced inflammation via the blockade of NF-κB activation in a Nur77-dependent manner. Additionally, B7 showed in vivo anti-inflammatory activity in the LPS-induced mice model of acute lung injury (ALI). These data suggest that the Nur77-targeting flavonoid derivatives can be particularly useful for further pharmaceutical development for the treatment of inflammatory diseases such as ALI.

Colchicine in coronary artery disease

Coronary artery disease (CAD) is a major cause of morbidity and mortality worldwide. Inflammation has been seen to be a key feature of atherosclerosis and CAD, with a raised C-reactive protein being a marker of poor prognosis. Thus, the role of anti-inflammatory agents has been investigated in CAD. Colchicine is a well-known, inexpensive drug with marked anti-inflammatory effects. Here, we discuss the role of colchicine in stable CAD and post-acute coronary syndrome. We suggest that colchicine may play a key role in prevention of cardiovascular events in patients with stable and unstable CAD as colchicine is associated with a reduction in the rate of myocardial infarction and other major cardiovascular outcomes.

Nutraceutical Strategies for Suppressing NLRP3 Inflammasome Activation: Pertinence to the Management of COVID-19 and Beyond

Inflammasomes are intracellular protein complexes that form in response to a variety of stress signals and that serve to catalyze the proteolytic conversion of pro-interleukin-1β and pro-interleukin-18 to active interleukin-1β and interleukin-18, central mediators of the inflammatory response; inflammasomes can also promote a type of cell death known as pyroptosis. The NLRP3 inflammasome has received the most study and plays an important pathogenic role in a vast range of pathologies associated with inflammation-including atherosclerosis, myocardial infarction, the complications of diabetes, neurological and autoimmune disorders, dry macular degeneration, gout, and the cytokine storm phase of COVID-19. A consideration of the molecular biology underlying inflammasome priming and activation enables the prediction that a range of nutraceuticals may have clinical potential for suppressing inflammasome activity-antioxidants including phycocyanobilin, phase 2 inducers, melatonin, and N-acetylcysteine, the AMPK activator berberine, glucosamine, zinc, and various nutraceuticals that support generation of hydrogen sulfide. Complex nutraceuticals or functional foods featuring a number of these agents may find utility in the prevention and control of a wide range of medical disorders.