[Preparation of hybrid exosomes based on bovine milk exosomes and liposomes and pharmacodynamic study of sinomenine loaded exosomes in treatment of rheumatoid arthritis].

This study investigates the therapeutic effect of hybrid exosomes loaded with sinomenine(SIN) obtained by membrane fusion of milk exosomes with liposomes in collagen-induced arthritis(CIA) rats. Exosomes were isolated from fresh bovine milk by sucrose density gradient centrifugation, while liposomes were prepared using the emulsion solvent evaporation-low temperature curing method. Hybrid exosomes were characterized after membrane fusion through co-incubation: The morphology was detected by transmission electron microscopy, the particle size and potential by nanoparticle size potentiostat, and the expressions of surface characteristic proteins CD63 and TSG101 before and after fusion by Western blot(WB). The drug loading capacity and encapsulation rate of sinomenine were measured after the loading of sinomenine on exosomes by ultrasonic method. The CIA rat model was induced by collagen antibody. The efficacy experiment consisted of the control group, model group, SIN group, SIN-liposome group, SIN-milk exosome group, SIN-hybrid exosome group and positive drug(dexamethasone) group. The changes in body mass of rats during administration were recorded. Besides, the foot swelling, immune organ index, arthritis index, microcirculation index, synovial histopathology, and serum inflammatory factor levels detected by enzyme-linked immunosorbent assay were observed for pharmacodynamical study. Under transmission electron microscopy, both hybrid exosomes and milk exosomes showed saucer-like appearance. After co-incubation, the exosome particle size increased from(97.92±3.42)nm to(132.70±4.07)nm, and the Zeta potential changed from(-2.01±0.33)mV to(-17.90±2.13)mV. WB assay showed that CD63 and TSG101 proteins were normally expressed in milk exosomes and hybrid exosomes. The encapsulation rate of milk exosomes was 31.64%±2.48%, with a drug loading of 2.35%±0.52%, while the hybrid exosomes exhibited an encapsulation rate of 48.21%±3.12% and drug loading of 3.17%±0.36%, as determined by the microplate reader. Pharmacodynamic results showed that compared with the model group, the general condition, swelling degree of foot, arthritis index and immune organ index of all drug administration groups were significantly improved(P<0.05, P<0.01); microvascular comprehensive score and vascular resistance were significantly decreased(P<0.05, P<0.01); serum levels of TNF-α, IL-1ß and IL-6 inflammatory factors were significantly decreased(P<0.01); and the lesions of synovial tissue were improved to some extent. Meanwhile, compared with the SIN group, SIN-liposome group and SIN-milk exosome group, the SIN-hybrid exosome group had a more stable and durable drug effect. The hybrid exosomes obtained by co-incubation of milk-derived exosomes with liposomes successfully improved the drug carrying capacity of exosomes and biocompatibility of liposomes. The hybrid exosomes loaded with sinomenine have good efficacy on CIA model rats, and can effectively solve the problems of TCM such as sinomenine, which have good efficacy but short biological half-life. The study provides new insights for the development of TCM and the treatment of diseases such as rheumatoid arthritis.

[Treatment of rheumatoid arthritis by injection of sinomenine solid lipid nanoparticles under a fluorescence endoscopic laser confocal microscope].

A fluorescence endoscopic laser confocal microscope(FELCM) was used to direct the injection of sinomenine solid lipid nanoparticles(Sin-SLN) into the joint, and the in vitro effectiveness of Sin-SLN in the treatment of rheumatoid arthritis(RA) was evaluated. Sin-SLN was prepared with the emulsion evaporation-low temperature curing method. The Sin-SLN prepared under the optimal conditions showed the encapsulation efficiency of 64.79%±3.12%, the drug loading of 3.84%±0.28%, the average particle size of(215.27±4.21) nm, and the Zeta potential of(-32.67±0.84) mV. Moreover, the Sin-SLN demonstrated good stability after sto-rage for 30 days. The rabbit model of RA was established by the subcutaneous injection of ovalbumin and complete Freund's adjuvant. Five groups were designed, including a control group, a model group, a Sin(1.5 mg·kg~(-1)) group, a Sin-SLN(1.5 mg·kg~(-1)) group, and a dexamethasone(positive drug, 1.0 mg·kg~(-1), ig) group. The control group and the model group only received puncture treatment without drug injection. After drug administration, the local skin temperature and knee joint diameter were monitored every day. The knee joint diameter and the local skin temperature were lower in the drug administration groups than in the model group(P<0.05, P<0.01). FELCM recorded the morphological alterations of the cartilage of knee joint. The Sin-SLN group showed compact tissue structure and smooth surface of the cartilage. Enzyme-linked immunosorbent assay(ELISA) was employed to determine the serum le-vels of interleukin-1(IL-1) and tumor necrosis factor-α(TNF-α). The findings revealed that the Sin-SLN group had lower IL-1 and TNF-α levels than the model group(P<0.05, P<0.01). Hematoxylin-eosin(HE) staining was employed to reveal the pathological changes of the synovial tissue, which were significantly mitigated in the Sin-SLN group. The prepared Sin-SLN had uniform particle size and high stability. Through joint injection administration, a drug reservoir was formed. Sin-SLN effectively alleviate joint swelling and cartilage damage of rabbit, down-regulated the expression of inflammatory cytokines, and inhibited the epithelial proliferation and inflammatory cell infiltration of the synovial tissue, demonstrating the efficacy in treating RA.

[Recent advances in nanocarrier-based drug delivery systems in treatment of rheumatoid arthritis].

Rheumatoid arthritis(RA) is a widely prevalent autoimmune inflammatory disease that severely affects patients' quality of life. Currently, conventional formulations against RA have several limitations, such as nonspecificity, poor efficacy, large drug dosages, frequent administration, and systemic side effects. Nanotechnology-based drug delivery systems have emerged as a promising stra-tegy for the diagnosis and treatment of RA since nanotechnology can overcome the limitations of traditional treatments and simplify the complexity of the disease. These systems enable targeted delivery of anti-inflammatory drugs to the inflamed areas through active and passive targeting, achieving specificity to the joints, overcoming the need for increased dosage and administration frequency, and reducing associated adverse reactions. This article aimed to review nanocarrier-based drug delivery systems in the field of RA and elucidate how nanosystems can be utilized to deliver therapeutic drugs to inflamed joints for controlling RA progression. By discussing the current issues and challenges faced by nanodrug delivery systems and highlighting the urgent need for solutions, this article offers theoretical support for further research on nanotechnology-based co-delivery systems in the future.

[PK/PD model of Chuanxiong gel plaster in treatment of rheumatoid arthritis].

In this experiment, the PK/PD fitting model of Chuanxiong(Chuanxiong Rhizoma) in the treatment of rheumatoid arthritis was established in the form of acupoint combined with external application gel paste. Firstly, the rheumatoid arthritis model was induced by ovalbumin, and the articular fluid of rabbits was extracted by microdialysis. The pharmacokinetic process of Chuanxiong in rabbit articular fluid was analyzed by UPLC-MS/MS, and the pharmacokinetic model was established. The pharmacodynamic effects of Chuanxiong on inflammatory factors IL-1ß, TNF-α, and IL-6 were analyzed by enzyme-linked immunosorbent assay(ELISA). The pharmacodynamic model was established, and the PK/PD model was obtained by fitting the data of pharmacokinetics and pharmacodynamics. The results of pharmacokinetics showed that the concentration of ligustrolide A in the articular cavity by drug administration on classical acupoint Zusanli(ST 36) was higher than that by Yanglingquan(GB 34), which reflected the advantage of typical acupoint, while ligustrazine concentration was higher after administration through Yanglingquan than through Zusanli, which was different from the traditional acupoint theory. The results of pharmacodynamics showed that the drug had lag effect. The PK/PD model was constructed by fitting the data. When IL-1ß was taken as the efficacy index, the PK/PD models of Chuanxiong in typical acupoint Zusanli group, atypical acupoint Yanglingquan group, and non-acupoint group were E=115.28C_e/(3 316.72+C_e), E=108.73C_e/(2 993.47+C_e), and E=101.34C_e/(3 028.51+C_e). When TNF-α was taken as the efficacy index, the PK/PD models of Chuanxiong in typical acupoint Zusanli group, atypical acupoint Yanglingquan group, and non-acupoint group were E=68.31C_e/(3 285.16+C_e), E=59.27C_e/(2 919.86+C_e), and E=53.61C_e/(2 862.87+C_e). When IL-6 was taken as the efficacy index, the PK/PD models of Chuanxiong in typical acupoint Zusanli group, atypical acupoint Yanglingquan group, and non-acupoint group were E=59.92C_e/(3 461.17+C_e), E=58.34C_e/(2 723.51+C_e), and E=49.17C_e/(2 862.76+C_e). The parameters showed that there were significant differences in E_(max), EC_(e50) and k_(eo). The analysis of data found that the PK/PD fitting effect of Zusanli, a typical acupoint, was the best, which proved that it was still the best site for drug administration. To sum up, it shows that there may be bidirectional selectivity between drugs and acupoints.