Exploring the translational potential of PLGA nanoparticles for intra-articular rapamycin delivery in osteoarthritis therapy.

Osteoarthritis (OA) is a prevalent joint disease that affects all the tissues within the joint and currently lacks disease-modifying treatments in clinical practice. Despite the potential of rapamycin for OA disease alleviation, its clinical application is hindered by the challenge of achieving therapeutic concentrations, which necessitates multiple injections per week. To address this issue, rapamycin was loaded into poly(lactic-co-glycolic acid) nanoparticles (RNPs), which are nontoxic, have a high encapsulation efficiency and exhibit sustained release properties for OA treatment. The RNPs were found to promote chondrogenic differentiation of ATDC5 cells and prevent senescence caused by oxidative stress in primary mouse articular chondrocytes. Moreover, RNPs were capable to alleviate metabolism homeostatic imbalance of primary mouse articular chondrocytes in both monolayer and 3D cultures under inflammatory or oxidative stress. In the mouse destabilization of the medial meniscus (DMM) model, intra-articular injection of RNPs effectively mitigated joint cartilage destruction, osteophyte formation, chondrocytes hypertrophy, synovial inflammation, and pain. Our study demonstrates the feasibility of using RNPs as a potential clinically translational therapy to prevent the progression of post-traumatic OA.

A facile and smart strategy to enhance bone regeneration with efficient vitamin D3 delivery through sterosome technology.

The spontaneous healing of critical-sized bone defects is often limited, posing an increased risk of complications and suboptimal outcomes. Osteogenesis, a complex process central to bone formation, relies significantly on the pivotal role of osteoblasts. Despite the well-established osteogenic properties of vitamin D3 (VD3), its lipophilic nature confines administration to oral or muscle injection routes. Therefore, a strategic therapeutic approach involves designing a multifunctional carrier to enhance efficacy, potentially incorporating it into the delivery system. Here, we introduce an innovative sterosome-based delivery system, utilizing palmitic acid (PA) and VD3, aimed at promoting osteogenic differentiation and facilitating post-defect bone regeneration. The delivery system exhibited robust physical characteristics, including excellent stability, loading efficiency, sustained drug release and high cellular uptake efficiency. Furthermore, comprehensive investigations demonstrated outstanding biocompatibility and osteogenic potential in both 2D and 3D in vitro settings. A critical-sized calvarial defect model in mice recapitulated the notable osteogenic effects of the sterosomes in vivo. Collectively, our research proposes a clinically applicable strategy for bone healing, leveraging PA/VD3 sterosomes as an efficient carrier to deliver VD3 and enhance bone regenerative effects.

Main-Chain Cationic Bile Acid Polymers Mimicking Facially Amphiphilic Antimicrobial Peptides.

Antibiotic-resistant bacterial infections have led to an increased demand for antibacterial agents that do not contribute to antimicrobial resistance. Antimicrobial peptides (AMPs) with the facially amphiphilic structures have demonstrated remarkable effectiveness, including the ability to suppress antibiotic resistance during bacterial treatment. Herein, inspired by the facially amphiphilic structure of AMPs, the facially amphiphilic skeletons of bile acids (BAs) are utilized as building blocks to create a main-chain cationic bile acid polymer (MCBAP) with macromolecular facial amphiphilicity via polycondensation and a subsequent quaternization. The optimal MCBAP displays an effective activity against Gram-positive methicillin-resistant Staphylococcus aureus (MRSA) and Gram-negative Escherichia coli, fast killing efficacy, superior bactericidal stability in vitro, and potent anti-infectious performance in vivo using the MRSA-infected wound model. MCBAP shows the low possibility to develop drug-resistant bacteria after repeated exposure, which may ascribe to the macromolecular facial amphiphilicity promoting bacterial membrane disruption and the generation of reactive oxygen species. The easy synthesis and low cost of MCBAP, the superior antimicrobial performance, and the therapeutic potential in treating MRSA infection altogether demonstrate that BAs are a promising group of building blocks to mimic the facially amphiphilic structure of AMPs in treating MRSA infection and alleviating antibiotic resistance.

Intrinsic antibacterial and osteoinductive sterosomes promote infected bone healing.

Open fractures and internal fixation implants are often accompanied by bacterial infection, leading to osteomyelitis, characterized by intractable bone infection and sequestrum formation, and can result in lifelong disability or fatal sepsis. As common clinical treatment strategies, high-dose antibiotic application and autologous bone transplantation face the risk of recurrence and donor site injury. Herein, we designed and prepared a novel drug delivery system by rational selection of the antibacterial single-chain amphiphile (cetylpyridinium chloride, CPC) and osteoinductive sterol (20S-hydroxycholesterol, Oxy) to formulate CPC/Oxy sterosomes. We demonstrate their excellent biocompatibility and antibacterial ability through 2D and 3D settings in vitro. In addition, the osteogenic differentiation of bone marrow mesenchymal stem cells was investigated in cell monolayers and a hydrogel environment. Moreover, a rat infected critical-sized calvarial defect model was employed to illustrate the effects of antibacterial and osteogenic CPC/Oxy sterosomes in vivo. Our results showed that CPC/Oxy sterosomes not only exterminated bacterial infections, but also enhanced calvarial healing without additional antibiotics, bone formation promoters or exogenous cells. This research provides a promising and effective multifunctional sterosomal platform for the treatment of infected bone defects, with the potential to be combined with therapeutic genes, and small molecule drugs.

Synergistic effect of the anti-PD-1 antibody with blood stable and reduction sensitive curcumin micelles on colon cancer.

Curcumin (1,7-bis(4-hydroxy-3-methoxyphenyl)-1,6-heptadiene-3,5-dione) is a potent anticancer drug with versatile biological activities, while the clinical translation of curcumin is severely limited due to its hydrophobicity, rapid elimination, and metabolism in the blood circulation. Herein, we aim to unravel the potential of curcumin as a synergistic agent with immunotherapy in the treatment of cancers. In an effort to minimize premature release and improve the systemic bioavailability, a superior blood stable and reduction sensitive curcumin micellar formulation, of which the release can be triggered by cancer cells, is rationally designed. We have synthesized a telodendrimer (mPEG-PLA-(LA)4) capable of forming reversible disulfide crosslinked micelles (DCMs). The curcumin loaded DCMs (Cur/DCMs) are spherical with a uniform size of 24.6 nm. The in vitro release profile demonstrates that curcumin releases significantly slower from DCMs than that from non-crosslinked micelles (NCMs), while the release can be accelerated with the increasing concentration of reducing agent glutathione (GSH). Intravenous administration of Cur/DCMs stably retains curcumin in the bloodstream and efficiently improves the systemic bioavailability. Furthermore, Cur/DCMs exhibit synergistic anticancer efficacy when combined with the anti-PD-1 antibody in an MC-38 colon cancer xenograft model. Our results potentiate the integration of blood stable curcumin nanoformulation and immunotherapy for cancer treatment.

[Risk factors of hypertension in IgA nephropathy].

OBJECTIVE: To explore the risk factors of hypertension in patients with IgA nephropathy in South China. METHODS: The clinical and renal pathological data of 280 primary IgA nephropathy patients diagnosed by biopsy were analyzed to extinguish the risk factors of hypertension. RESULTS: A total of 96 patients were suffered with hypertension (34.3%). A single-variable analysis showed that the age (>or= 40 years), body weight (>or= 60 kg), absence of macrohematuria, duration of disease (>or= 60 months), blood urea nitrogen >or= 8 mmol/L, serum creatinine (>or= 133 micromol/L), hyperuricaemia, degree of 24 h-proteinuria (>or= 1.5 g), segmental glomerular lesions (>or= 25%), globe glomerular sclerosis (>or= 10%), tubular atrophy (>or= 25%), interstitial fibrosis (>or= 25%), interstitial inflammation (>or= 25%) and arteriole hypertrophy (>or= 10%) were all risk factors related to hypertension; multivariate logistic regression analysis showed that serum creatinine, age, arteriole hypertrophy, body weight and 24 h-proteinuria were the independent risk factors. CONCLUSION: Many factors were related the hypertension in patients with IgA nephropathy, while serum creatinine, age, arteriole hypertrophy, body weight and 24 h-proteinuria were the independent risk factors of hypertension.

[A comparative study of the clinicopathological features in patients with IgA nephropathy with elevated uric acid level].

OBJECTIVE: To explore the changes in the clinicopathological features of patients with IgA nephropathy with elevated uric acid level. METHODS: A total of 171 patients with IgA nephropathy diagnosed at biopsy were classified into 3 groups, namely normotensive group with normal level uric acid (group 1), normotensive group with elevated uric acid level (group 2), and hypertensive group with elevated uric acid level (group 3). The clinicopathological features were compared between the 3 groups. RESULTS: From group 1 to group 3, the disease duration became elongated, body weight increased, systolic and diastolic pressures elevated, blood urea nitrogen and serum creatinine increased, glomerular filtration rate decreased, and 24-h urine protein increased; the apolipoprotein A, high-density lipoprotein and albumin levels decreased, while apolipoprotein B100, triglyceride, cholesterol and low-density lipoprotein increased. The glomerular damage, tubulointerstitial lesions and arteriole hypertrophy worsened, and Lee's grade III changes were predominant in group 1, grade III or IV in group 2 and grades III-V in group 3. Mesangial proliferative glomerulonephritis was the major pathological type in groups 1 and 2, as compared with focal segmental glomerulonephritis or sclerosing glomerulonephritis in group 3. CONCLUSION: Patients with IgA nephropathy and elevated uric acid level have greater clinicopathological damage than those with normal uric acid level, and hypertension further aggravates such damages.