Pharmacokinetics, distribution and efficacy of triptolide PLGA microspheres after intra-articular injection in a rat rheumatoid arthritis model

Research Progress on Immunomodulatory Effects of Poly (Lactic-co- Glycolic Acid) Nanoparticles Loaded with Traditional Chinese Medicine Monomers

Immunomodulatory mechanisms are indispensable and key factors in maintaining the balance of the environment in humans. When the immune function of the immune system is impaired, autoimmune diseases occur. Excessive body fatigue, natural aging of the human body, malnutrition, genetic factors and other reasons cause low immune function, due to which the body is prone to being infected by bacteria or cancer. Clinically, the existing therapeutic drugs still have problems such as high toxicity, long treatment cycle, drug resistance and high price, so we still need to explore and develop a high efficiency and low toxicity drug. Poly(lactic-co-glycolic acid) (PLGA) refers to a nontoxic polymer compound that exhibits excellent biocompatibility. Traditional Chinese medicine (TCM) monomers come from natural plants, and have the characteristics of high efficiency and low toxicity. Applying PLGA to TCM monomers can make up for the defects of traditional dosage forms, improve bioavailability, reduce the frequency and dosage of drug use, and reduce toxicity and side effects, thus having the characteristics of sustained release and targeting. Accordingly, PLGA nanoparticles loaded with TCM monomers have been the focus of development. The previous research on drug loading advantages, preparation methods, and immune regulation of TCM PLGA nanoparticles is summarized in the following sections.

Microcarriers in application for cartilage tissue engineering: Recent progress and challenges

Successful regeneration of cartilage tissue at a clinical scale has been a tremendous challenge in the past decades. Microcarriers (MCs), usually used for cell and drug delivery, have been studied broadly across a wide range of medical fields, especially the cartilage tissue engineering (TE). Notably, microcarrier systems provide an attractive method for regulating cell phenotype and microtissue maturations, they also serve as powerful injectable carriers and are combined with new technologies for cartilage regeneration. In this review, we introduced the typical methods to fabricate various types of microcarriers and discussed the appropriate materials for microcarriers. Furthermore, we highlighted recent progress of applications and general design principle for microcarriers. Finally, we summarized the current challenges and promising prospects of microcarrier-based systems for medical applications. Overall, this review provides comprehensive and systematic guidelines for the rational design and applications of microcarriers in cartilage TE.

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This review summarized fabrication techniques and cartilage repaired application of microcarriers.

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The appropriate materials and design principle for microcarriers in cartilage tissue engineering are discussed.

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Promising future perspectives and challenges in microcarriers fields are outlined.