Targeted Delivery of Curcumin to Polyethylene-Induced Osteolysis by Magnetically Guided Zoledronate-Anchored Poly Lactic-Co-Glycolic Acid Nanoparticles via Repressing NF-κB Signaling

Magnetic Aggregation-Induced Bone-Targeting Nanocarrier with Effects of Piezo1 Activation and Osteogenic-Angiogenic Coupling for Osteoporotic Bone Repair

Osteoporosis, characterized by an imbalance in bone homeostasis, is a global health concern. Bone defects are difficult to heal in patients with osteoporosis. Classical drug treatments for osteoporotic bone defects have unsatisfactory efficacy owing to side effects and imprecise delivery problems. In this study, a magnetic aggregation-induced bone-targeting poly(lactic-co-glycolic acid, PLGA)-based nanocarrier (ZOL-PLGA@Yoda1/SPIO) is synthesized to realize dual-targeted delivery and precise Piezo1-activated therapy for osteoporotic bone defects. Piezo1 is an important mechanotransducer that plays a key role in regulating bone homeostasis. To achieve dual-targeting properties, ZOL-PLGA@Yoda1/SPIO is fabricated using zoledronate (ZOL)-decorated PLGA, superparamagnetic iron oxide (SPIO), and Piezo1-activated molecule Yoda1 via the emulsion solvent diffusion method. Bone-targeting molecular mediation and magnetic aggregation-induced properties can jointly and effectively achieve precise delivery to localized bone defects. Moreover, Yoda1 loading enables targeted and efficient mimicking of mechanical signals and activation of Piezo1. Experiments in vivo and in vitro demonstrate that ZOL-PLGA@Yoda1/SPIO can activate Piezo1 in bone defect areas of osteoporotic mice, improve osteogenesis through YAP/β-catenin signaling axis, promote a well-coordinated osteogenesis-angiogenesis coupling, and significantly accelerate bone reconstruction within the defects without noticeable side effects. Overall, this novel dual-targeting nanocarrier provides a potentially effective strategy for the clinical treatment of osteoporotic bone defects.

Beyond the polysaccharide and glycoconjugate vaccines for Streptococcus pneumoniae: Does protein/peptide nanovaccines hold promises?

Streptococcus pneumoniae having almost 98 serotypes and being common cause of acute otitis media, pneumonia, bacteremia, meningitis etc., which results in high mortality and morbidity globally. Although vaccines like PCV-13 and PPV-23 are available, some problems like serotype replacement and poor immunogenicity in children, old age and immunocompromised people has been observed. To overcome these drawbacks protein/peptide-based vaccine can be a good strategy as these provides wide serotype coverage. However, immunogenicity of protein subunit vaccines is lower, that issue can be solved by using adjuvants. Recently nanoparticles as an adjuvant for vaccine delivery being used, which has provided not only good immunogenicity but also improved delivery and efficiency of protein-based vaccines. In this review we have discussed the latest advancement of nanoparticles-based protein/peptide vaccine delivery for Streptococcus pneumoniae.

Therapeutic Effects of Curcumin Liposomes and Nanocrystals on Inflammatory Osteolysis: In Vitro and In Vivo Comparative Study

Curcumin could inhibit periprosthetic osteolysis induced by wear debris and adherent endotoxin, which commonly cause prosthesis loosening and negatively influence the long-term survival of joint arthroplasty. However, its limited water solubility and poor stability pose challenges for its further clinical application. To address these issues, we developed curcumin liposomes for intraarticular injection, as liposomes possess good lubricant capacity and pharmacological synergy with curcumin. Additionally, a nanocrystal dosage form was prepared to enable comparison with the liposomes based on their ability to disperse curcumin effectively. A microfluidic method was used for its controllability, repeatability, and scalability. The Box-Behnken Design was employed to screen the formulations and flow parameters, while computational fluid dynamics was used to simulate the mixing process and predict the formation of liposomes. The optimized curcumin liposomes (Cur-LPs) had a size of 132.9nm and an encapsulation efficiency of 97.1%, whereas the curcumin nanocrystals (Cur-NCs) had a size of 172.3nm. Both Cur-LPs and Cur-NCs inhibited LPS-induced pro-inflammatory polarization of macrophages and reduced the expression and secretion of inflammatory factors. The mouse air pouch model further demonstrated that both dosage forms attenuated inflammatory cell infiltration and inflammatory fibrosis in subcutaneous tissues. Interestingly, the anti-inflammatory effect of Cur-LPs was more potent than that of Cur-NCs, both in vitro and in vivo, although the cellular uptake of Cur-NCs was quicker. In conclusion, the results demonstrate that Cur-LPs have great potential for the clinical treatment of inflammatory osteolysis and that the therapeutic effect is closely related to the liposomal dosage form.

Ubiquitin-specific peptidases: Players in bone metabolism

Osteoporosis is an ageing-related disease, that has become a major public health problem and its pathogenesis has not yet been fully elucidated. Substantial evidence suggests a strong link between overall age-related disease progression and epigenetic modifications throughout the life cycle. As an important epigenetic modification, ubiquitination is extensively involved in various physiological processes, and its role in bone metabolism has attracted increasing attention. Ubiquitination can be reversed by deubiquitinases, which counteract protein ubiquitination degradation. As the largest and most structurally diverse cysteinase family of deubiquitinating enzymes, ubiquitin-specific proteases (USPs), comprising the largest and most structurally diverse cysteine kinase family of deubiquitinating enzymes, have been found to be important players in maintaining the balance between bone formation and resorption. The aim of this review is to explore recent findings highlighting the regulatory functions of USPs in bone metabolism and provide insight into the molecular mechanisms governing their actions during bone loss. An in-deep understanding of USPs-mediated regulation of bone formation and bone resorption will provide a scientific rationale for the discovery and development of novel USP-targeted therapeutic strategies for osteoporosis.

Zoledronate combined metal-organic frameworks for bone-targeting and drugs deliveries

Medicine treatments for bone-related diseases such as osteoporosis, bone metastasis, osteomyelitis, and osteolysis are often limited by insufficient drug concentration at the lesion sites owing to the low perfusion of bone tissue. A carrier that can deliver multiple bone destruction site-targeting drugs is required to address this limitation. Here, we reported a novel bone-targeting nano-drug delivery platform formed by the integration of zoledronate (ZOL) and zeolitic imidazolate framework-8 (ZIF-8) nanoparticles. The ZOL mixed zeolitic imidazolate framework (ZZF) nanoparticles were synthesized in water at room temperature (25 °C), where many biomacromolecules could maintain their activity. This allowed the ZZF nanoparticles to adapt the encapsulation ability and pH response release property from ZIF-8 and the excellent bone targeting performance of ZOL simultaneously. Considering the ease of preparation and biomacromolecule-friendly drug delivery of this nano platform, it may be useful in treating bone-related diseases.

Extracellular Vesicles from Human Urine-Derived Stem Cells Ameliorate Particulate Polyethylene-Induced Osteolysis

Purpose

Wear debris particle-induced periprosthetic osteolysis is a severe complication of total joint replacement that results in aseptic loosening and subsequent arthroplasty failure. No effective therapeutic agents or drugs have been approved to prevent or treat osteolysis; thus, revision surgery is often needed. Extracellular vesicles (EVs) are vital nanosized regulators of intercellular communication that can be directly applied to promote tissue repair and regeneration. In this study, we assessed the therapeutic potential of EVs from human urine-derived stem cells (USCs) (USC-EVs) in preventing ultrahigh-molecular-weight polyethylene (UHMWPE) particle-induced osteolysis.

Methods

USCs were characterized by measuring induced multipotent differentiation and flow cytometry. USC-EVs were isolated and characterized using transmission electron microscopy (TEM), dynamic light scattering (DLS) and Western blotting. RAW264.7 cells and bone marrow mesenchymal stem cells (BMSCs) were cultured with USC-EVs to verify osteoclast differentiation and osteoblast formation, respectively, in vitro. The effects of USC-EVs were investigated on a UHMWPE particle-induced murine calvarial osteolysis model by assessing bone mass, the inflammatory reaction, and osteoblast and osteoclast formation.

Results

USCs differentiated into osteogenic, adipogenic and chondrogenic cells in vitro and were positive for CD44, CD73, CD29 and CD90 but negative for CD34 and CD45. USC-EVs exhibited a cup-like morphology with a double-layered membrane structure and were positive for CD63 and TSG101 and negative for calnexin. In vitro, USC-EVs promoted the osteogenic differentiation of BMSCs and reduced proinflammatory factor production and osteoclastic activity in RAW264.7 cells. In vivo, local injection of USC-EVs around the central sites of the calvaria decreased inflammatory cytokine generation and osteolysis compared with the control groups and significantly increased bone formation.

Conclusion

Based on our findings, USC-EVs prevent UHMWPE particle-induced osteolysis by decreasing inflammation, suppressing bone resorption and promoting bone formation.