Chemopreventive effects of a curcumin-like diarylpentanoid [2,6-bis(2,5-dimethoxybenzylidene)cyclohexanone] in cellular targets of rheumatoid arthritis in vitro

In Silico Study and Effects of BDMC33 on TNBS-Induced BMP Gene Expressions in Zebrafish Gut Inflammation-Associated Arthritis

The bone morphogenic protein (BMP) family is a member of the TGF-beta superfamily and plays a crucial role during the onset of gut inflammation and arthritis diseases. Recent studies have reported a connection with the gut-joint axis; however, the genetic players are still less explored. Meanwhile, BDMC33 is a newly synthesized anti-inflammatory drug candidate. Therefore, in our present study, we analysed the genome-wide features of the BMP family as well as the role of BMP members in gut-associated arthritis in an inflammatory state and the ability of BDMC33 to attenuate this inflammation. Firstly, genome-wide analyses were performed on the BMP family in the zebrafish genome, employing several in silico techniques. Afterwards, the effects of curcumin analogues on BMP gene expression in zebrafish larvae induced with TNBS (0.78 mg/mL) were determined using real time-qPCR. A total of 38 identified BMP proteins were revealed to be clustered in five major clades and contain TGF beta and TGF beta pro peptide domains. Furthermore, BDMC33 suppressed the expression of four selected BMP genes in the TNBS-induced larvae, where the highest gene suppression was in the BMP2a gene (an eight-fold decrement), followed by BMP7b (four-fold decrement), BMP4 (four-fold decrement), and BMP6 (three-fold decrement). Therefore, this study reveals the role of BMPs in gut-associated arthritis and proves the ability of BDMC33 to act as a potential anti-inflammatory drug for suppressing TNBS-induced BMP genes in zebrafish larvae.

Immunomodulatory Effects of Curcumin in Rheumatoid Arthritis: Evidence from Molecular Mechanisms to Clinical Outcomes

Rheumatoid arthritis (RA) is a chronic immune-mediated inflammatory disorder characterized by the destruction of the joint and bone resorption. The production of pro-inflammatory cytokines and chemokines, dysregulated functions of three important subtypes of T helper (T_H) cells including T_H1, T_H17, and regulator T (Treg) cells are major causes of the initiation and development of RA. Moreover, B cells as a source of the production of several autoantibodies play key roles in the pathogenesis of RA. The last decades have seen increasingly rapid advances in the field of immunopharmacology using natural origin compounds for the management of various inflammatory diseases. Curcumin, a main active polyphenol compound isolated from turmeric, curcuma longa, possesses a wide range of pharmacologic properties for the treatment of several diseases. This review comprehensively will assess beneficial immunomodulatory effects of curcumin on the production of pro-inflammatory cytokines and also dysregulated functions of immune cells including T_H1, T_H17, Treg, and B cells in RA. We also seek the clinical efficacy of curcumin for the treatment of RA in several recent clinical trials. In conclusion, curcumin has been found to ameliorate RA complications through modulating inflammatory and autoreactive responses in immune cells and synovial fibroblast cells via inhibiting the expression or function of pro-inflammatory mediators, such as nuclear factor-κB (NF-κB), activated protein-1 (AP-1), and mitogen-activated protein kinases (MAPKs). Of note, curcumin treatment without any adverse effects can attenuate the clinical symptoms of RA patients and, therefore, has therapeutic potential for the treatment of the diseases.

Tolerogenic dendritic cells suppress titanium particle-induced inflammation

Aseptic loosening is a major complication of prosthetic joint surgery. The leading cause of arthroplasty failure is particulate wear debris such as titanium particles. Dendritic cells (DCs) are one type of immune cells that play an important role in the initiation and progression of inflammatory processes. DCs can develop into tolerogenic DCs (tolDCs), which present an alternative therapeutic strategy for inflammatory disorders. Previously, antigen-specific tolDCs were generated, which showed a promising effect in treating inflammatory arthritis and immune thrombocytopenia. The present study reports that tolDCs effectively inhibited titanium particle-induced inflammation in an air-pouch mouse model by decreasing pro-inflammatory cytokines. In addition, a mechanistic study demonstrated that tolDCs significantly protected against titanium particle-induced inflammatory processes in vitro by releasing anti-inflammatory cytokines, such as interleukin-10. Collectively, these findings not only demonstrate that tolDCs play an important role in inhibiting titanium particle-induced inflammation but also provide a potential alternative for the prevention or treatment of titanium particle-induced inflammation.

Topical Nano-Vesicular Spanlastics of Celecoxib: Enhanced Anti-Inflammatory Effect and Down-Regulation of TNF-α, NF-кB and COX-2 in Complete Freund's Adjuvant-Induced Arthritis Model in Rats

BACKGROUND

Rheumatoid arthritis (RA) is an autoimmune disease that underlies chronic inflammation of the synovial membrane. Non-steroidal anti-inflammatory drugs (NSAIDs) are commonly used to treat RA. However, a long list of adverse events associated with long-term treatment regimens with NSAIDs negatively influences patient compliance and therapeutic outcomes.

AIM

The aim of this work was to achieve site-specific delivery of celecoxib-loaded spanlastic nano-vesicle-based delivery system to the inflamed joints, avoiding systemic administration of large doses.

METHODOLOGY

To develop spanlastic nanovesicles for transdermal delivery of celecoxib, modified injection method was adopted using Tween 80 or Brij as edge activators. Entrapment efficiency, vesicle size, ex vivo permeation, and morphology of the prepared nano-vesicles were characterized. Carbopol-based gels containing the selected formulations were prepared, and their clarity, pH, rheological performance, and ex vivo permeation were characterized. Celecoxib-loaded niosomes and noisome-containing gels were developed for comparison. The in vivo efficacy of the selected formulations was evaluated in a rat model of Freund's complete adjuvant-induced arthritis. Different inflammatory markers including TNF-α, NF-кB and COX-2 were assessed in paw tissue before and after treatment.

RESULTS

The size and entrapment efficiency of the selected spanlastic nano-vesicle formulation were 112.5 ± 3.6 nm, and 83.6 ± 2.3%, respectively. This formulation has shown the highest transdermal flux and permeability coefficient compared to the other investigated formulations. The spanlastics-containing gel of celecoxib has shown transdermal flux of 6.9 ± 0.25 µg/cm2/hr while the celecoxib niosomes-containing gel and unprocessed celecoxib-loaded gel have shown 5.2 ± 0.12 µg/cm2/hr and 0.64 ± 0.09 µg/cm2/hr, respectively. In the animal model of RA, the celecoxib-loaded spanlastics-containing gel significantly reduced edema circumference and significantly suppressed TNF-α, NF-кB and COX-2 levels compared to the niosomes-containing gel, the marketed diclofenac sodium gel, and unprocessed celecoxib-loaded gel.

CONCLUSION

The spanlastic nano-vesicle-containing gel represents a more efficient site-specific treatment for topical treatment of chronic inflammation like RA, compared to commercial and other conventional alternatives.

Pharmacological appraisal of ligustrazine based cyclohexanone analogs as inhibitors of inflammatory markers

The targeting of pro-inflammatory enzymes becomes a therapeutic intervention when acute inflammation is proliferating in pathological conditions. This research is intended to carry out an evaluation of inhibiting and inducing enzymes with inflammatory associations with 28 cyclohexanone analogs based on the ligustrazine. Tests were undertaken with inhibitor screening assay kits using a range of synthetic compounds to investigate how they could inhibit the activity of cyclooxygenase (COX) enzymes, secretory phospholipase A₂ (sPLA₂), and lipoxygenase (LOX) enzyme. Significant and similar inhibitory activities against sPLA₂ with were noted with synthetic compounds which included 1f and 1g (IC₅₀ = 2.2 μM). The optimal inhibitory activity regarding LOX enzyme was shown with compounds 1d (IC₅₀ = 8.1 μM) and 1e (IC₅₀ = 7.5 μM). Additionally, the compounds 1b, 1d, 1e, 2n, and 2o were shown to be significant inhibitors of COX-1 activity with IC₅₀ values 0.09 to 0.7 μM. The outcomes of assays for COX inhibition demonstrated that the same compounds had a further strong inhibitive influence on the COX-2 enzyme, and certain compounds such as 1d, 1e, and 2n demonstrated enhanced potency compared with positive controls.

Curcumin: hopeful treatment of hemophilic arthropathy via inhibition of inflammation and angiogenesis

Introduction: Hemophilic arthropathy (HA) is a serious complication among hemophilic patients causing a wide range of morbidity due to the inflammatory reactions followed by repeated episodes of bleeding. This condition has recently been shown to be accompanied by angiogenesis. The cascade starts with iron accumulation leading to an increase in CD⁶⁸⁺ and CD^11b+ cells responsible for initiating the inflammation.Areas covered: During inflammation, different factors and cytokines such as interleukin 1 (IL-1), IL-6, and tumor necrosis factor α (TNF-α) actively play parts in the pathogenesis of HA and also angiogenesis. It has been demonstrated that different pro-angiogenic and angiogenic factors such as hypoxia-inducible factor 1α (HIF-1α), vascular endothelial growth factor (VEGF), oxidative stress and matrix metalloproteinases (MMPs) are also important in the pathogenesis of HA. Curcumin is known for its strong anti-inflammatory and anti-angiogenic potentials. This agent is able to inhibit the mentioned inflammatory and angiogenic factors such as IL-1, IL-6, TNF-α, VEGF, MMPs, and HIF-1α. Also, as well as anti-angiogenic and anti-inflammatory activity, curcumin has a strong antioxidant potential and can decrease oxidative stress.Expert opinion: It seems that curcumin could be considered as a possible agent for the treatment of HA through inhibition of inflammation, oxidative stress, and angiogenesis.

Oxidative stress in inflammatory cells of patient with rheumatoid arthritis: clinical efficacy of dietary antioxidants

Rheumatoid arthritis (RA) is an autoimmune disease responsible for significant human morbidity in modern life. However, oxidative stress is one of the key markers for determining pathophysiology of patients with RA. The interaction between cellular immune system and body's endogenous and/or exogenous antigens produce reactive oxygen species (ROS) and reactive nitrogen species (RNS) in autoimmune disease like RA. ROS and RNS include highly toxic superoxide (O₂^-) and peroxynitrite (ONOO^-) radicals, which activate the signaling cascades of inflammatory cells to synthesize pro-inflammatory cytokines and chemokines. Previous studies reported that Th1 cytokines could promote the development of autoimmune disorders like RA, whereas the Th2 cytokines may attenuate the same diseases. An increased awareness of the relationship between food and health led to a tremendous increase of antioxidant research in the last decade. Evaluation of the efficacy of dietary antioxidants is also becoming highly acceptable in RA research. A number of dietary phytomolecules are already established as having antioxidant activity in isolated synovial cellular infiltrate or peripheral blood neutrophils and lymphocytes. This review aims to highlight the oxidative stress in inflammatory cells of patients with RA and to summarize the clinical relevance of dietary antioxidants as a first step in assessing beneficial effect, safety and dose safety ratio in patients with RA.

Curcumin as a potential protective compound against cardiac diseases

Curcumin, which was first used 3000 years ago as an anti-inflammatory agent, is a well-known bioactive compound derived from the active ingredient of turmeric (Curcuma longa). Previous research has demonstrated that curcumin has immense therapeutic potential in a variety of diseases via anti-oxidative, anti-apoptotic, and anti-inflammatory pathways. Cardiac diseases are the leading cause of mortality worldwide and cause considerable harm to human beings. Numerous studies have suggested that curcumin exerts a protective role in the human body whereas its actions in cardiac diseases remain elusive and poorly understood. On the basis of the current evidence, we first give a brief introduction of cardiac diseases and curcumin, especially regarding the effects of curcumin in embryonic heart development. Secondly, we analyze the basic roles of curcumin in pathways that are dysregulated in cardiac diseases, including oxidative stress, apoptosis, and inflammation. Thirdly, actions of curcumin in different cardiac diseases will be discussed, as will relevant clinical trials. Eventually, we would like to discuss the existing controversial opinions and provide a detailed analysis followed by the remaining obstacles, advancement, and further prospects of the clinical application of curcumin. The information compiled here may serve as a comprehensive reference of the protective effects of curcumin in the heart, which is significant to the further research and design of curcumin analogs as therapeutic options for cardiac diseases.

Curcumin, inflammation, and chronic diseases: how are they linked?

It is extensively verified that continued oxidative stress and oxidative damage may lead to chronic inflammation, which in turn can mediate most chronic diseases including cancer, diabetes, cardiovascular, neurological, inflammatory bowel disease and pulmonary diseases. Curcumin, a yellow coloring agent extracted from turmeric, shows strong anti-oxidative and anti-inflammatory activities when used as a remedy for the prevention and treatment of chronic diseases. How oxidative stress activates inflammatory pathways leading to the progression of chronic diseases is the focus of this review. Thus, research to date suggests that chronic inflammation, oxidative stress, and most chronic diseases are closely linked, and the antioxidant properties of curcumin can play a key role in the prevention and treatment of chronic inflammation diseases.