Multifunctional nanoparticles of sinomenine hydrochloride for treat-to-target therapy of rheumatoid arthritis via modulation of proinflammatory cytokines.

Sinomenine is a bioactive alkaloid isolated from the Chinese medicinal plant of Sinomenium acutum (Thunb.) Rehd.et Wils. Currently, sinomenine hydrochloride (SIN) preparations, classified as a natural disease-modifying anti-rheumatic drug (nDMARD), have been used for therapy of rheumatoid arthritis (RA); however, the efficacy of SIN was seriously limited by its short half-life, low bioavailability, and dose-dependent adverse reactions. In this study, a biomimetic nanocomplex based on Prussian blue nanoparticles (PB NPs) was developed for overcoming clinical limitations of SIN and accordingly improving its efficacy. In vitro studies showed that the nanocomplexes significantly inhibited abnormal proliferation of fibroblast-like synoviocytes (FLSs) by scavenging reactive oxygen species (ROS) and inhibiting secretion of proinflammatory cytokines. In vivo imaging demonstrated that the improved immune-escape properties of the nanocomplexes resulted in markedly increased half-life of circulation and levels of accumulated drugs at arthritic sites of adjuvant-induced arthritis (AIA) rats. Notably, the nanocomplexes significantly suppressed joint inflammation and protected against bone destruction of AIA rats by inhibiting inflammatory cytokine secretion of the synovial macrophages and FLSs. These results indicate that the nanocomplexes provide an excellent carrier for controlled release and targeted accumulation of SIN within the arthritic sites, which consequently achieve disease-remitting effects of SIN on RA.

Lactate metabolism in rheumatoid arthritis: Pathogenic mechanisms and therapeutic intervention with natural compounds.

BACKGROUND: Rheumatoid arthritis (RA) is a common chronic and systemic autoimmune disease characterized by persistent inflammation and hyperplasia of the synovial membrane, the degradation of cartilage, and the erosion of bones in diarthrodial joints. The inflamed joints of patients with RA have been recognized to be a site of hypoxic microenvironment which results in an imbalance of lactate metabolism and the accumulation of lactate. Lactate is no longer considered solely a metabolic waste product of glycolysis, but also a combustion aid in the progression of RA from the early stages of inflammation to the late stages of bone destruction. PURPOSE: To review the pathogenic mechanisms of lactate metabolism in RA and investigate the potential of natural compounds for treating RA linked to the regulation of imbalance in lactate metabolism. METHODS: Research advances in our understanding of lactate metabolism in the pathogenesis of RA and novel pharmacological approaches of natural compounds by targeting lactate metabolic signaling were comprehensively reviewed and deeply discussed. RESULTS: Lactate produced by RA synovial fibroblasts (RASFs) acts on targeted cells such as T cells, macrophages, dendritic cells and osteoclasts, and affects their differentiation, activation and function to accelerate the development of RA. Many natural compounds show therapeutic potential for RA by regulating glycolytic rate-limiting enzymes to limit lactate production, and affecting monocarboxylate transporter and acetyl-CoA carboxylase to inhibit lactate transport and conversion. CONCLUSION: Regulation of imbalance in lactate metabolism offers novel therapeutic approaches for RA, and natural compounds capable of targeting lactate metabolic signaling constitute potential candidates for development of drugs RA.

A pH-Driven indomethacin-loaded nanomedicine for effective rheumatoid arthritis therapy by combining with photothermal therapy.

Rheumatoid arthritis (RA) is a systemic autoimmune disease characterised by inflammatory micro-environments in the joints. Indomethacin (IND), a conventional nonsteroidal anti-inflammatory drug (NSAID), has been used for the therapy of RA. However, the poor solubility and serious side effects of oral administration of IND significantly limit its efficacy. In this study, we have synthesized biomimetic IND-loaded Prussian blue (PB) nanoparticles (IND@PB@M@HA) with hyaluronic acid (HA) modification for increasing the solubility and targeting the ability of IND to the inflamed joints. The application of hybrid cell membranes on the NPs endowed immune escape of IND@PB@M@HA NPs, which accordingly extended the circulation time in the blood. In vitro assay demonstrated that the combination of nanomedicine and photothermal therapy produced a powerful anti-inflammatory effect by reducing the levels of inflammatory factors and cell viability of activated macrophages and NPs possessed obvious pH-responsiveness. In vivo assay demonstrated that the nanomedicine for synergistic photothermal therapy exhibited desirable pharmacodynamics and pharmacokinetic properties at ultra-low drug dosage in a rat model of adjuvant-induced arthritis, which was confirmed by inflammatory suppression, bone erosion remission, and negligible adverse effects. In summary, the proposed nanomedicine has the potential role for targeted anti-inflammatory therapy of RA.