Daphnetin induces apoptosis in fibroblast-like synoviocytes from collagen-induced arthritic rats mainly via the mitochondrial pathway

Nanodrug delivery systems targeting ferroptosis as an innovative therapeutic approach for Rheumatoid Arthritis

Rheumatoid Arthritis (RA) is a chronic inflammatory disease characterized by joint inflammation, progressive cartilage degradation, and bone erosion. Recent research has implicated ferroptosis not only in autoimmune hepatitis but also in the pathogenesis and progression of autoimmune disorders like RA. Consequently, numerous therapeutic strategies have begun to target the ferroptosis pathway, particularly in the design and development of nanodrug delivery systems (NDDSs). While previous reviews have comprehensively discussed the mechanisms of ferroptosis, related signaling pathways, and NDDS materials, recent studies have further elucidated the interplay between ferroptosis and various metabolic pathways, providing a robust theoretical basis for the design of NDDS-based ferroptosis strategies. This review focuses on investigating the role of ferroptosis in the development of RA, aiming to elucidate how targeting ferroptosis can offer novel therapeutic concepts and potential treatments for RA patients. Specifically, it summarizes the design strategies of ferroptosis-based NDDSs via different pathways and highlights the feasibility of RA treatment regimens based on the ferroptosis mechanism. Furthermore, the review critically discusses the current limitations of NDDSs and offers perspectives on future research directions in this field.

Daphnetin alleviates inflammation and promotes autophagy via the AMPK/mTOR pathway in gouty arthritis

Gouty arthritis (GA) is an inflammatory disease resulting from monosodium urate (MSU) crystal deposition in joints and surrounding tissues. Daphnetin (DAP) is a coumarin derivative with potent anti-inflammatory activity. Nonetheless, whether DAP can protect against MSU-induced acute GA remains unclarified. In this study, C57BL/6 mice were injected intra-articularly with MSU crystal suspension to induce acute GA. THP-1 cells were stimulated with MSU to mimic the microenvironment of GA in vitro. Hematoxylin-eosin staining was conducted to observe the pathological changes in mouse synovial tissues. ELISA and RT-qPCR were employed for inflammatory cytokine level determination. Immunofluorescence staining was performed to estimate LC3 expression in THP-1 cells. Western blotting was used for protein expression analysis. The results showed that DAP pretreatment mitigated MSU-elicited ankle joint swelling and synovial damage in mice. Moreover, DAP hindered proinflammatory factor expression and promoted autophagy in MSU-stimulated GA mice and THP-1 cells. Mechanistically, DAP induced AMPK activation and mTOR inactivation. Blocking AMPK signaling counteracted DAP-mediated effects on inflammation and autophagy in MSU-stimulated THP-1 cells. In conclusion, DAP prevents MSU-elicited GA by alleviating inflammation and enhancing autophagy via AMPK/mTOR signaling transduction.

Programmed Cell Death in Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a chronic, progressive, systemic autoimmune disease characterised by synovial inflammation, synovial pannus formation and subsequent destruction of articular cartilage and bone. Programmed cell death (PCD), encompassing apoptosis, autophagy, pyroptosis, necroptosis, and ferroptosis, plays a pivotal role in the pathogenesis of RA. An imbalance in PCD causes a variety of immune cells to release large amounts of inflammatory factors and mediators that exacerbate not only chronic synovial inflammation, but also bone and joint damage. The purpose of this article is to review the relevant studies between PCD and RA, with the aim of providing further insights and considerations for a deeper understanding of the pathogenesis of RA and to guide clinical management.

Role of reactive oxygen species and mitochondrial damage in rheumatoid arthritis and targeted drugs

Rheumatoid arthritis (RA) is an autoimmune disease characterized by synovial inflammation, pannus formation, and bone and cartilage damage. It has a high disability rate. The hypoxic microenvironment of RA joints can cause reactive oxygen species (ROS) accumulation and mitochondrial damage, which not only affect the metabolic processes of immune cells and pathological changes in fibroblastic synovial cells but also upregulate the expression of several inflammatory pathways, ultimately promoting inflammation. Additionally, ROS and mitochondrial damage are involved in angiogenesis and bone destruction, thereby accelerating RA progression. In this review, we highlighted the effects of ROS accumulation and mitochondrial damage on inflammatory response, angiogenesis, bone and cartilage damage in RA. Additionally, we summarized therapies that target ROS or mitochondria to relieve RA symptoms and discuss the gaps in research and existing controversies, hoping to provide new ideas for research in this area and insights for targeted drug development in RA.

Daphnetin: A bioactive natural coumarin with diverse therapeutic potentials

Daphnetin (DAP), a coumarin derivative extracted from Daphne species, is biologically active phytochemical with copious bioactivities including anti-inflammatory, anti-oxidant, neuroprotective, analgesic, anti-pyretic, anti-malarial, anti-bacterial, anti-arthritic, neuroprotective, hepatoprotective, nephroprotective, and anti-cancer activities. A wide range of studies have been conducted exploring the significance and therapeutic potential of DAP. This study reviewed various databases such as NCBI, PubMed, Web of Science, Scopus and Google Scholar for published research articles regarding the sources, synthesis, and various bioactivities of DAP using different key words, including but not limited to "pharmacological activities," "sources," "neuroprotective effect," "synthesis," "cancer," "anti-inflammatory effect" of "daphnetin." Furthermore, this review encompasses both in-vivo and in-vitro studies on DAP for treating various diseases. A comprehensive review of the literature revealed that the DAP had a promising pharmacological and safety profile, and could be employed as a pharmaceutical moiety to treat a variety of illnesses including microbial infections, cancer, arthritis, hepatic damage, inflammation and neurological anomalies. The current review intends to provide an in-depth focus on all pharmacological activities and therapeutic approaches for the pharmaceutical and biomedical researchers.

Aconiti lateralis radix praeparata total alkaloids exert anti-RA effects by regulating NF-κB and JAK/STAT signaling pathways and promoting apoptosis

Aconiti Lateralis Radix Praeparata (“Fuzi” in Chinese) is one of the traditional herbs widely used to intervene rheumatoid arthritis (RA), while Fuzi total alkaloids (FTAs) are the main bioactive components. However, the treatment targets and specific mechanisms of FTAs against RA have not been fully elucidated. The purpose of the present study was to confirm the anti-rheumatism effects of FTAs and reveal its potential molecular mechanisms. In TNF-α-induced MH7A cells model, we found that FTAs showed inhibitory effects on proliferation. While, FTAs significantly decreased the expression levels of IL-1β, IL-6, MMP-1, MMP-3, PGE2, TGF-β, and VEGF. FTAs also enhanced the progress of apoptosis and arrested the cell cycle at G0/G1 phase to prevent excessive cell proliferation. In addition, FTAs inhibited the hyperactivity of NF-κB and JAK/STAT signaling pathways, and regulated the cascade reaction of mitochondrial apoptosis signaling pathway. The results suggested that FTAs exerted anti-inflammatory effects by inhibiting NF-κB and JAK/STAT signaling pathways, promoted apoptosis by stimulating mitochondrial apoptosis signaling pathway, and inhibited cell proliferation by modulating cell cycle progression.

New bitongling (NBTL) ameliorates rheumatoid arthritis in rats through inhibiting JAK2/STAT3 signaling pathway

Rheumatoid arthritis (RA) is featured by a variety of physical symptoms and fibroblast-like synoviocytes (FLSs) abnormal proliferation. Increasing evidence has demonstrated that traditional Chinese medicine exerts an important role in RA treatment. New bitongling (NBTL) as one of the traditional Chinese medicine has been reported to be involved in the progression of RA, but the exact mechanism is unclear. In our study, we intended to investigate the effect of NBTL on RA to identify the mechanisms related to JAK2/STAT3 signaling pathway. Extracts of Tripterygium wilfordii (TW), a traditional Chinese herbal medicine, have been widely used for treating RA in China for several decades, so, TW was used as a positive control drug for TBNL. RA rats were constructed by immunization with collagen type II to evaluate the action of NBTL in vivo. Body weight and arthritic index were evaluated. Hematoxylin and Eosin staining was performed to analysis the morphological changes of ankle joints tissue. TUNEL and flow cytometry were performed to examine cell apoptosis, while CCK8 and Ethynyl-2'-deoxyuridine (EdU) were performed to examine cell proliferation. In addition, the markers of inflammation were detected by Western blot, ELISA, and RT-qPCR. Firstly, we find that rats treated with NBTL or TW not only reduced swelling degree and bone destruction, but also repressed IL-1 β and IL-6 levels. In addition, NBTL and TW could increase the weight of rats, and promote the level of IL-10 and IL-4 in vivo. Furthermore, NBTL inhibited inflammation of FLS, induced cell apoptosis and hindered cell proliferation, which was reversed by dipeptidyl peptidase (DPP), a JAK2/STAT3 pathway activator. Taken together, NBTL potentially retarded RA via JAK2/STAT3 pathway, highlighting novel mechanisms associated with RA.