A Solid–Liquid Composite Lubricating “Nano‐Snowboard” for Long‐Acting Treatment of Osteoarthritis

Abstract

Osteoarthritis is a chronic inflammatory disease characterized by cartilage degeneration. Anti-inflammatory therapy has limited effects, and effective reduction of cartilage wear through lubrication is essential. In vivo stability and lubricity of commercial lubricants are insufficient, leading to failure of lubricating treatment and progression of osteoarthritis. To address these issues, new therapeutic methods combining anti-inflammation and stable highperformance lubrication are developed. Inspired by the sliding mechanism of snowboards, a "nano-snowboard" by modifying molybdenum disulfide (MoS 2 ) with a biomimetic phospholipid polymer poly (dopamine methacrylamide-co-2-methacryloyloxyethyl phosphorylcholine) (PDMPC) and loading anti-inflammatory drug diclofenac sodium (DS), namely MoS 2 -PDMPC-DS, has been synthesized. MoS 2 with a 2D layered structure and photothermal properties, serves as solid lubricant and drug carrier. Meanwhile, the modification of PDMPC on the surface of MOS 2 avoids the oxidative denaturation of MoS 2 in a physiological environment, forming solid-liquid composite lubrication and improving the lubricity and stability of MoS 2 in the joint cavity. In vitro and in vivo experiments show that MoS 2 -PDMPC-DS can stay in the joint cavity for more than one week and exert long-lasting lubrication and anti-inflammatory effects to treat osteoarthritis effectively. This solid-liquid composite lubricating nano-snowboard provides a new idea for synergistic anti-inflammatory and lubricating treatment of osteoarthritis.

Photothermal Nanomaterials: A Powerful Light-to-Heat Converter

“…To achieve complete eradication of tumors, NIR light with long wavelengths, especially in the NIR-II window, is preferable for the deep tissue penetration during PTT. ,, Moreover, photothermal nanomaterials with desired absorption wavelengths can be readily designed to avoid the intrinsic light absorption of biological chromophores, leading to the reduction of phototoxicity in normal tissues. The modulation of the size, shape, and surface functionalization of photothermal nanomaterials, as well as the biological microenvironment, can be performed to improve the delivery efficiency and therapeutic efficacy of photothermal agents. ,− Robust photothermal nanomaterials have been extensively developed to possess specific physicochemical and pharmaceutical properties for the reduction of adverse effects and the enhancement of therapeutic efficacy. ,,,, In addition, PTT has also been carried out in clinical pilot trials as a safe and effective therapeutic modality. The clinical progresses of PTT with various photothermal nanomaterials have been widely made for the treatment of head and neck cancer, coronary atherosclerosis, diabetic macular abnormalities, age-related macular degeneration, prostate cancer, and genitourinary syndrome of menopause (national clinical trials: NCT 00848042, NCT 01270139, NCT 01975103, NCT 02569892, NCT 02680535, NCT 03288883). , A single-treatment clinical device study of AuroLase Therapy for the direct focal ablation of prostate tissue was demonstrated by the company of Nanospectra Biosciences .…”

Recent advances of mussel-inspired materials in osteoarthritis therapy

“…− species in phosphatidylcholine lipids can orient a large number of free water molecules around these charges through the charge-dipole interactions to form a hydration layer [87,94]. At present, various biomimetic zwitterionic polymers, including poly (2methacryloyloxyethyl phosphocholine) (PMPC) [89,95], poly(methacrylic acid 3-sulfopropyl ester potassium salt) (PSPMA) [94], and poly(sulfomethacrylic acid betaine) (PSBMA) [87,96], have been reported to reduce the interfacial friction of the articular cartilage. However, these zwitterionic polymers face problems such as insufficient bulk density, unstable binding with cartilage tissues, and high surface roughness, which affect their lubrication performance in cartilage tissue [97].…”

A cyclic brush zwitterionic polymer based pH-responsive nanocarrier-mediated dual drug delivery system with lubrication maintenance for osteoarthritis treatment

“…Moreover, OA is associated with increased mechanical friction of the joints, and its pathological process is irreversible. 1,2 Currently, there are generally two effective OA interventions: (1) enhancing the lubricating properties of the joint or promoting cartilage repair; and (2) drug therapy, but due to the lack of blood vessels in the articular cartilage, the absorption rate of oral anti-inflammatory drugs is low, and frequent oral or intravenous administration may cause drug resistance, overdose, and gastrointestinal problems. 3–6 Therefore, the development of a synergistic treatment modality that can enhance lubrication and precise specific drug delivery is highly desirable for OA patients.…”

“…So far, the most widely used joint injection materials in the clinical stage include hyaluronic acid (HA), 19 corticosteroids (GC), 20,21 platelet-rich plasma (PRP) 22 and stem cell therapy. 23 Although it has been reported that diclofenac sodium (DS), 1,24 curcumin (Cur), 25,26 loxoprofen (LXP), 27 etc. can effectively reduce the inflammatory response and oxidative stress levels in OA model rats.…”