Combination of UHPLC-QE-MS and Network Pharmacology to Reveal the Mechanism of Fufang-Duzhong-Jiangu Granules for Treating Knee Osteoarthritis

UHPLC-QE-MS technology and network pharmacology are used to comprehensively analyze and validate the potential mechanism of Fufang-Duzhong-Jiangu granules (FFDZ) in treating knee osteoarthritis (KOA). UHPLC-QE-MS technology and content-weighted construction of databases and screening conditions are used to obtain key component targets. CTD, Gene Cards, and DisGeNET databases are used to define KOA-related targets. Target pathways are selected through GO enrichment analysis and KEGG enrichment analysis. Additionally, a KOA rat model was established using the type II collagenase injection method. The efficacy of FFDZ on type II collagenase-induced KOA rats was evaluated through behavioral, biochemical, and histopathological assessments, and the predicted pathways were confirmed through Western blot. These results show that the rats significantly increased in knee joint diameter, decreased weight-bearing capacity of the right leg, and elevated levels of IL-6 and IL-1β in serum, all with a significance level of p < 0.05. Through CT and HE staining, it was shown that KOA rats exhibit distinct pathological structures. These results show that FFDZ exerts its anti-KOA effects by regulating the RAS pathway. This study found that FFDZ improves KOA in rats by inhibiting the expression of proteins related to the RAS pathway.

Race for the surface between THP-1 macrophages and Staphylococcus aureus on various titanium implants with well-defined topography and wettability

Gristina et al. (1987) suggested that the fate of a biomaterial is decided in a "race for the surface" between pathogens and the host. To gain deeper insight into the mechanisms behind this concept, we investigated the "race for the surface" across three co-culture scenarios with THP-1 macrophages and Staphylococcus aureus (1:1 ratio), varying the order of addition: (i) simultaneous, (ii) macrophages first, and (iii) S. aureus first, on six Ti6Al4V-ELI surfaces modified with specific topographies and wettability. The outcome of the race for the surface was not influenced by these biomaterials but by the chronological introduction of macrophages and S. aureus. When macrophages and S. aureus arrived simultaneously, macrophages won the race, leading to the lowest number of viable S. aureus through rapid phagocytosis and killing. When macrophages arrived and established first, macrophages still prevailed but under greater challenge resulting from the lower bacterial killing efficiency of adherent macrophages and numerous viable intracellular bacteria, supporting the concept of the so-called immunocompromised zone around implants (upregulation of TLR-2 receptor and pro-inflammatory IL-1β). When S. aureus arrived first establishing a biofilm, bacteria won the race, leading to macrophage dysfunction and cell death (upregulation of FcγR and TLR-2 receptors, NF-κB signaling, NOX2 mediated reactive oxygen species), contributing to a persistent biofilm phenotype (upregulation of clfA, icaA, sarA, downregulation of agrA, hld, lukAB) and intracellular survival of S. aureus (lipA upregulation). The clinical implications are bacterial colonization of the implant and persistence of intracellular bacteria in periprosthetic tissues, which can lead to infection chronicity. STATEMENT OF SIGNIFICANCE: Gristina et al. (1987) suggested that the fate of a biomaterial is decided in a "race for the surface" between bacterial pathogens and host cells. There is a lack of in vitro co-culture models and knowledge on macrophage-S. aureus interactions on biomaterial surfaces, and no studies have evaluated the expression of virulence factors in S. aureus biofilms. We have successfully developed co-culture models and molecular panels, and elucidated important cellular and molecular interactions between macrophages and S. aureus on a broad range of titanium biomaterials with well-defined surface topography and wettability. Our findings highlight the critical role of biofilm formation and the chronological order of bacteria or macrophage arrival in determining the fate of the race for the surface.

Therapeutic Controlled Release Strategies for Human Osteoarthritis

Osteoarthritis is a progressive, irreversible debilitating whole joint disease that affects millions of people worldwide. Despite the availability of various options (non-pharmacological and pharmacological treatments and therapy, orthobiologics, and surgical interventions), none of them can definitively cure osteoarthritis in patients. Strategies based on the controlled release of therapeutic compounds via biocompatible materials may provide powerful tools to enhance the spatiotemporal delivery, expression, and activities of the candidate agents as a means to durably manage the pathological progression of osteoarthritis in the affected joints upon convenient intra-articular (injectable) delivery while reducing their clearance, dissemination, or side effects. The goal of this review is to describe the current knowledge and advancements of controlled release to treat osteoarthritis, from basic principles to applications in vivo using therapeutic recombinant molecules and drugs and more innovatively gene sequences, providing a degree of confidence to manage the disease in patients in a close future.

MMP-9 responsive hydrogel promotes diabetic wound healing by suppressing ferroptosis of endothelial cells

Ferroptosis plays a crucial role in the progression of diabetic wounds, suggesting potential therapeutic strategies to target ferroptosis. Transient receptor potential ankyrin 1 (TRPA1) is a non-selective calcium channel that acts as a receptor for a variety of physical or chemical stimuli. Cinnamaldehyde (CA) is a specific TRPA1 agonist. In in vitro experiments, we observed that high glucose (HG) treatment induced endothelial cell ferroptosis, impairing cell function. CA successfully inhibited endothelial cell ferroptosis, improving migration, proliferation, and tube formation. Further mechanistic studies showed that CA-activated TRPA1-induced Ca2+ influx promoted the phosphorylation of calmodulin-dependent protein kinase II (CaMKII) and nuclear factor-E 2-related factor 2 (Nrf2) translocation, which contributed to the elevation of glutathione peroxidase 4 (GPX4), leading to the inhibition of endothelial cell ferroptosis. In addition, CA was incorporated into an MMP-9-responsive injectable duplex hybrid hydrogel (CA@HA-Gel), allowing its efficient sustained release into diabetic wounds in an inflammation-responsive manner. The results showed that CA@HA-Gel inhibited wound endothelial cell ferroptosis and significantly promoted diabetic wound healing. In summary, the results presented in this study emphasize the potential therapeutic application of CA@HA-Gel in the treatment of diseases associated with ferroptosis.

Macrophage Polarization in the Osteoarthritis Pathogenesis and Treatment

Osteoarthritis (OA) is a prevalent degenerative disorder that severely impacts quality of life due to pain and disability. Although the pathophysiology of OA remains incompletely understood, recent research highlights the role of synovial inflammation in OA onset and progression, driven primarily by inflammatory infiltrates, especially macrophages, in the synovium. These macrophages respond to the local microenvironment, polarizing into either pro-inflammatory (M1) or anti-inflammatory (M2) subtypes. This review focuses on the role of macrophage polarization in OA pathogenesis and treatment, emphasizing how M1/M2 polarization is influenced by pathways such as STAT, NF-κB, caspase, and MAPK. These pathways induce low-grade inflammation within OA-affected joints, altering chondrocyte metabolism, inhibiting cartilage repair, and impairing mesenchymal stem cell chondrogenesis, thereby contributing to OA progression. Additionally, this review discusses potential therapies targeting macrophage polarization, encompassing compounds, proteins, cells, and microRNAs, to offer insights into novel treatment strategies for OA.

Rational Design of Advanced Gene Delivery Carriers: Macrophage Phenotype Matters

Nucleic acid delivery in hard-to-transfect macrophages have attracted increasing attention in diverse applications such as defence against bacterial infection. Regulated by microenvironments in specific applications, macrophages have a heterogenous nature and exist in different phenotypes with diverse functions, e.g., pro-inflammatory and anti-inflammatory. However, it is not clear whether macrophage phenotype affects nucleic acid delivery, and which one is harder to transfect, and the design of nucleic acid carriers in harder-to-transfect macrophage phenotypes is largely unexplored. Herein, it is first revealed that nucleic acid delivery efficacy in macrophages is influenced by phenotype: IL-4-treated "M2-like" macrophages with suppressed mammalian target of rapamycin complex 1 (mTORC1) levels are harder-to-transfect than "M1-like" macrophages for mRNA and DNA. This knowledge is then translated to the purpose-design of gene delivery carriers for harder-to-transfect M2 phenotype macrophages dominant upon bacteria immune evasion. By loading chloroquine in tetrasulfide bond-containing organosilica nanoparticles, the resultant composite promotes macrophage M2 polarization to M1 and increases mTORC1 levels for enhanced translation. The design is demonstrated in vitro and in vivo for pathogenic Escherichia coli (E. coli) and methicillin-resistant Staphylococcus aureus (MRSA) infections. It is expected that the findings may provide new knowledge and gene delivery solutions in other applications where the M2 phenotype macrophage is dominant.

Natural Products in the Prevention of Degenerative Bone and Joint Diseases: Mechanisms Based on the Regulation of Ferroptosis

Degenerative bone and joint diseases (DBJDs), characterized by osteoporosis, osteoarthritis, and chronic inflammation of surrounding soft tissues, are systemic conditions primarily affecting the skeletal system. Ferroptosis, a programmed cell death pathway distinct from apoptosis, autophagy, and necroptosis. Accumulating evidence suggests that ferroptosis is intricately linked to the pathogenesis of DBJDs, and targeting its regulation could be beneficial in managing these conditions. Natural products, known for their anti-inflammatory and antioxidant properties, have shown unique advantages in preventing DBJDs, potentially through modulating ferroptosis. This article provides an overview of the latest research on ferroptosis, with a focus on its role in the pathogenesis of DBJDs and the therapeutic potential of natural products targeting this cell death pathway, offering novel insights for the prevention and treatment of DBJDs.

Targeted Delivery of Peptide Nucleic Acid by Biomimetic Nanoparticles based on Extracellular Vesicle-coated Mesoporous Silica Nanoparticles

BACKGROUND

Peptide nucleic acid (PNA) plays an important role in antimicrobial activity, but its cellular permeability is poor. To overcome this limitation, we constructed biomimetic nanoparticles by using extracellular vesicle (EV)-coated mesoporous silicon nanoparticles (MSNs) to deliver PNA to Staphylococcus aureus (S. aureus) and improve its antisense therapeutic effect.

METHODS

MSN was prepared by the sol-gel method, and EV was extracted by affinity resin chromatography. EV was coated on MSN by simple sonication (50 W, 3 mins) to prepare biomimetic nanoparticles with PNA-loaded MSN as the core and EV isolated from S. aureus as the shell.

RESULTS

The MSN prepared by the sol-gel method had a uniform particle size (100 nm) and well-defined pore size for loading PNA with good encapsulation efficiency (62.92%) and drug loading (7.74%). The concentration of EV extracted by affinity resin chromatography was about 1.74 mg/mL. EV could be well coated on MSN through simple ultrasonic treatment (50 W, 3 mins), and the stability and blood compatibility of MSN@ EV were good. Internalization experiments showed that EV could selectively enhance the uptake of biomimetic nanoparticles by S. aureus. Preliminary in vitro antibacterial tests revealed that PNA@MSN@EV exhibited enhanced antibacterial activity against S. aureus and had stronger bactericidal activity than free PNA and PNA@MSN at equivalent PNA concentrations (8 μM).

CONCLUSION

Biomimetic nanoparticles based on EV-coated MSN offer a new strategy to improve the efficacy of PNA for the treatment of bacterial infections, and the technology holds promise for extension to the delivery of antibiotics that are traditionally minimally effective or prone to resistance.

Nanocarrier-Mediated Dermal Drug Delivery System of Antimicrobial Agents for Targeting Skin and Soft Tissue Infections

Antimicrobial resistance in disease-causing microbes is seen as a severe problem that affects the entire world, makes therapy less effective, and raises mortality rates. Dermal antimicrobial therapy becomes a desirable choice in the management of infectious disorders since the rising resistance to systemic antimicrobial treatment frequently necessitates the use of more toxic drugs. Nanoparticulate systems such as nanobactericides, which have built-in antibacterial activity, and nanocarriers, which function as drug delivery systems for conventional antimicrobials, are just two examples of the treatment methods made feasible by nanotechnology. Silver nanoparticles, zinc oxide nanoparticles, and titanium dioxide nanoparticles are examples of inorganic nanoparticles that are efficient on sensitive and multidrug-resistant bacterial strains both as nanobactericides and nanocarriers. To stop the growth of microorganisms that are resistant to standard antimicrobials, various antimicrobials for dermal application are widely used. This review covers the most prevalent microbes responsible for skin and soft tissue infections, techniques to deliver dermal antimicrobials, topical antimicrobial safety concerns, current issues, challenges, and potential future developments. A thorough and methodical search of databases, such as Google Scholar, PubMed, Science Direct, and others, using specified keyword combinations, such as "antimicrobials," "dermal," "nanocarriers," and numerous others, was used to gather relevant literature for this work.

Risk-stratified lifetime risk and incidence of hip fracture and falls in middle-aged and elderly Chinese population: The China health and retirement longitudinal study

Background

Hip fracture (HF) is one of the most prevalent orthopedic conditions among the elderly, with falls being the primary risk factor for HF. With the surge of aged population, China is facing great challenges from HF and falls. However, a comprehensive long-term observation of risk factors affecting HF and falls and their association are little reported at a national level.

Methods

The longitudinal cohort was established using the China Health and Retirement Longitudinal Study (CHARLS) data from 2011 to 2018. The incidence density and multi-risk-stratified lifetime risk (up to 90 years of age) of falls and HF were studied at index ages of 50, 60, and 70, as well as the lifetime risk stratified by six regions in China, based on the modified Kaplan-Meier method with Statistical Analysis System (SAS).

Results

This study identified 17 705 subjects aged 50-89. The incidence density of falls was 65.07 and 47.53 per 1000 person-years in women and men, respectively. The incidence density of HF was also higher in women at 5.58 per 1000 person-years than in men at 4.88. By age 50, the lifetime risk of experiencing a HF was 18.58 % for women and 13.72 % for men. Vision and hearing abilities were significantly related to the lifetime risk of both falls and HF. Obesity-related factors presented age-relevant relationships with lifelong risks. Lack of naps, poor lower limb strength, and physical capabilities were indicative of HF risk. The north-western region of China had the lowest lifetime risk of falls but highest risk of HF, while other regions showed a consistent trend between falls and HF.

Conclusion

The aging population worldwide faces a considerable risk of falls and HF. Several risk factors were identified in this study using a Chinese population, relating to disease history, lifestyle habits, health status and physical function, and the risks differed among six regions in China. Future precautionary management programs, as well as patient self-awareness are necessary for improving the prevention of falls and HF to reduce their incidence in the aging population.

The translational potential of this article

With the greatest aged population worldwide, China faces the unparalleled challenge on public health. The study poses the lifetime risk of hip fracture and falls stratified by multiple risk factors in people from 45 to 90 in a national scale, which would shed a light on the early and continuous prevention of such injury.

Evaluation of biological performance of 3D printed trabecular porous tantalum spine fusion cage in large animal models

Background

The materials for artificial bone scaffolds have long been a focal point in biomaterials research. Tantalum, with its excellent bioactivity and tissue compatibility, has gradually become a promising alternative material. 3D printing technology shows unique advantages in designing complex structures, reducing costs, and providing personalized customization in the manufacture of porous tantalum fusion cages. Here we report the pre-clinical large animal (sheep) study on the newly developed 3D printed biomimetic trabecular porous tantalum fusion cage for assessing the long-term intervertebral fusion efficacy and safety.

Methods

Porous tantalum fusion cages were fabricated using laser powder bed fusion (LPBF) and chemical vapor deposition (CVD) methods. The fusion cages were characterized using scanning electron microscopy (SEM) and mechanical compression tests. Small-Tailed Han sheep served as the animal model, and the two types of fusion cages were implanted in the C3/4 cervical segments and followed for up to 12 months. Imaging techniques, including X-ray, CT scans, and Micro CT, were used to observe the bone integration of the fusion cages. Hard tissue sections were used to assess osteogenic effects and bone integration. The range of motion (ROM) of the motion segments was evaluated using a biomechanical testing machine. Serum biochemical indicators and pathological analysis of major organs were conducted to assess biocompatibility.

Results

X-ray imaging showed that both the 3D-printed and chemical vapor deposition porous tantalum fusion cages maintained comparable average intervertebral disc heights. Due to the presence of metal artifacts, CT and Micro CT imaging could not effectively analyze bone integration. Histomorphology data indicated that both the 3D-printed and chemical vapor deposition porous tantalum fusion cages exhibited similar levels of bone contact and integration at 3, 6, and 12 months, with bone bridging observed at 12 months. Both groups of fusion cages demonstrated consistent mechanical stability across all time points. Serum biochemistry showed no abnormalities, and no significant pathological changes were observed in the heart, liver, spleen, lungs, and kidneys.

Conclusion

This study confirms that 3D-printed and chemical vapor deposition porous tantalum fusion cages exhibit comparable, excellent osteogenic effects and long-term biocompatibility. Additionally, 3D-printed porous tantalum fusion cages offer unique advantages in achieving complex structural designs, low-cost manufacturing, and personalized customization, providing robust scientific support for future clinical applications.

The translational potential of this article

The translational potential of this paper is to use 3D printed biomimetic trabecular porous tantalum spine fusion cage with bone trabecular structure and validating its feasibility in large animal models (sheep). This study provides a basis for further research into the clinical application of the 3D printed biomimetic trabecular porous tantalum spine fusion cage.

Trends and Advances in Antimicrobial Surface Modification for Orthopedic Implants (2014-2024)

The failure of orthopedic implants can significantly impact patients physiologically, psychologically, and economically. A bibliometric study of the field of surface modification for antimicrobial purposes in orthopedic implants provides insights into its developmental trajectory and offers valuable predictions for future advancements, thus playing a pivotal role in guiding research in this domain. Relevant publications on surface modification for antimicrobial purposes in orthopedic implants published between 2014 and 2024 were selected from the Web of Science (Core Collection) dataset and analyzed using VOSviewer and Citespace. The analysis encompassed 725 articles. Over the past decade, there has been a steady increase in the number of publications related to surface modification for antimicrobial purposes in orthopedic implants, with China emerging as the primary contributor. Novel antimicrobial materials development, osteogenesis, and angiogenesis have become focal areas of research interest in this domain. Surface modification for antimicrobial purposes in orthopedic implants garners increasing attention. Research in this field is anticipated to expand, with future focus likely to revolve around novel material applications, repair outcomes, and underlying mechanisms.

THE PLASMA CONCENTRATIONS OF ESSENTIAL TRACE ELEMENTS IN WOMEN WITH CANCER OF BREAST- OR CERVIX

Background

Derangement of trace elements which could be due to systemic inflammation or oxidative stress is thought to be directly or indirectly involved in carcinogenesis.

Aim

To evaluate plasma trace elements in female patients with cancer of breast- or cervix.

Material and Methods

This study was carried out in the Departments of Immunology and Radiation Oncology, University of Ibadan, Nigeria. Thirty (30) patients with cervical cancer, 30 patients with breast cancer and 30 age-matched females without cancer as control were included in the study. Plasma separated from venous blood was analysed for the concentrations of zinc (Zn), iron (Fe), selenium (Se) and copper (Cu) using Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). The sixty cancer patients were newly diagnosed and in a stable state.

Results

The mean plasma levels of Fe and Cu were significantly reduced in patients with breast cancer- or cervical cancer compared with control. The plasma concentrations of Fe, Cu, Zn and Se were significantly reduced in all patients having breast cancer and those in stage 2 compared with cervical cancer patients.

Conclusion

Available data further support a previous suggestion that blood levels of metal varies with different cancers. Thus, a need for differential supplementation based on cancer types when modulation of trace element levels becomes a therapeutic option.

Engineered Magneto-Piezoelectric Nanoparticles-Enhanced Scaffolds Disrupt Biofilms and Activate Oxidative Phosphorylation in Icam1+ Macrophages for Infectious Bone Defect Regeneration

Infectious bone defects pose significant clinical challenges due to persistent infection and impaired bone healing. Icam1+ macrophages were identified as crucial and previously unrecognized regulators in the repair of bone defects, where impaired oxidative phosphorylation within this macrophage subset represents a significant barrier to effective bone regeneration. To address this challenge, dual-responsive iron-doped barium titanate (BFTO) nanoparticles were synthesized with magnetic and ultrasonic properties. These nanoparticles were further loaded with the anti-inflammatory agent curcumin and coated with engineered mesenchymal stem cell membranes (EMM) modified with γ3 peptide, creating BFTO-Cur@EMM nanoparticles specifically designed to target Icam1+ macrophages. These nanoparticles were shown to disrupt bacterial biofilms under alternating magnetic fields (AMF) and to activate oxidative phosphorylation and osteogenic immune responses in Icam1+ macrophages via low-intensity pulsed ultrasound (LIPUS). Transcriptomic sequencing and validation experiments demonstrated that this approach activates oxidative phosphorylation (OXPHOS) by stimulating the JAK2-STAT3 pathway and inhibiting the MAPK-JNK pathway, thereby promoting the polarization of Icam1+ macrophages toward a pro-reparative phenotype and enhancing the secretion of pro-angiogenic and osteogenic cytokines. These nanoparticles were subsequently integrated into quaternized chitosan (QCS) and tricalcium phosphate (TCP) to create a bioink for three-dimensional (3D) printing anti-infection QT/BFTO-Cur@EMM bone repair scaffolds. In vivo studies indicated that these scaffolds significantly improved the healing of infectious bone defects without causing thermal damage to surrounding tissues. This work highlights the potential of this material and the targeting of Icam1+ macrophages as an effective strategy for simultaneously controlling infection and promoting bone regeneration.

Isosakuranetin inhibits subchondral osteoclastogenesis for attenuating osteoarthritis via suppressing NF-κB/CXCL2 axis

As the most predominant form of arthritis, osteoarthritis (OA) is featured with irreversible progress and involvement of the whole joint. Since OA onset, abnormal mechanical load initiates excessive osteoclastogenesis, evolving a rapid turnover of subchondral bone, cyst creation, synovitis, cartilage degradation, and ultimately resulting in joint failure. Additionally, aberrant vascularization and nociceptive pain are invoked by osteoclast-induced angiogenesis and sensory innervation in the subchondral bone. Rhizoma anemarrhenae (Zhimu) has been extensively demonstrated to show multiple pharmacological effects including anti-inflammation, anti-aging, and immunomodulation. Herein, Broussonin a (BRA), Markogein (MAN), and Isosakuranetin (ISN) derived from Rhizoma anemarrhenae, were initially discovered for their affinity with Bone marrow mononuclear cell (BMMC) membranes using the Cell membrane chromatography/Time of flight mass spectrometry (CMC/TOFMS) method, while only ISN exerted a significant inhibitory effect on RANKL-induced osteoclastogenesis in BMMC in vitro. Intriguingly, we disclosed that ISN blunted the overactivation of Tartrate-resistant acid phosphatase positive (TRAP+) osteoclasts in subchondral bone in OA mice, as indicated by enhanced bone volume/total volume (BV/TV), trabecular number (Tb.N), and trabeculae thickness (Tb.Th), as well as diminished trabecular pattern factor (Tb.pf). Treatment with ISN also impaired aberrant angiogenesis and nociceptive reaction in the subchondral bone marrow. Moreover, ISN hindered the loss of articular cartilage proteoglycan and lowered the Osteoarthritis Research Society International (OARSI) grade, boosting the expression amount of Aggrecan (ACAN) and Collagen II (COL II) positive cells while reducing Matrix metalloproteinase 13 (MMP-13) positive cells. For mechanisms, We verified that ISN hampered subchondral osteoclastogenesis by blocking nuclear factor kappa light chain enhancer of activated B cells (NF-κB) signaling and C-X-C Motif Chemokine Ligand 2 (CXCL2) stimulation. Taken together, we reveal that ISN impedes the progression of OA by preventing hyperactivated subchondral osteoclastogenesis via suppressing the NF-κB/CXCL2 axis.

Effect of an α-calcium sulfate hemihydrate/treated dentin matrix composite to regenerate bone in critically sized SD rat calvarial defects

Introduction

α-Calcium sulfate hemihydrate (α-CSH) is a widely used artificial bone graft material, but it suffers from rapid deterioration and limited osteoinductivity. This study aims to develop composite cements by combining treated dentin matrix (TDM) with α-CSH to enhance osteogenic properties for the healing of bone deformities.

Methods

The composite cements were prepared by mixing treated dentin matrix (TDM) with α-calcium sulfate hemihydrate (α-CSH) and characterized for their mechanical, morphological, and chemical properties using a universal mechanical testing machine, scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier-transform infrared (FTIR) spectroscopy. The biological performance was assessed by measuring osteoblast proliferation using the CCK-8 test and evaluating new bone formation in a calvarial bone defect model in rats.

Results

The compressive strength of the TDM/α-CSH cements decreased with increasing TDM mass ratio, while SEM analysis revealed a distinct three-dimensional porous network structure and increased surface roughness upon thorough mixing. XRD and FTIR studies confirmed the physical mixture of the two materials without phase changes. The TDM/α-CSH composites significantly stimulated osteoblast proliferation, which was dependent on the TDM content, and demonstrated superior enhancement in new bone formation as confirmed by X-ray examination and micro-CT analysis.

Discussion

The findings suggest that TDM/α-CSH composite cements have promising potential as an alternative for repairing bone defects due to their improved mechanical properties, osteoblast proliferation, and enhanced new bone formation in vivo.

Conclusion

TDM/α-CSH composite cements show potential as a novel bone graft material, offering advantages in terms of mechanical strength, osteoconductivity, and osteoinductivity, making them a viable option for bone repair applications.

Mechanisms of Vitamins Inhibiting Ferroptosis

Ferroptosis is an iron-dependent form of cell death, which is characterized by the uncontrolled and overwhelming peroxidation of cell membrane lipids. Ferroptosis has been implicated in the progression of various pathologies, including steatotic liver, heart failure, neurodegenerative diseases, and diabetes. Targeted inhibition of ferroptosis provides a promising strategy to treat ferroptosis-related diseases. Multivitamins, including vitamins A, B, C, D, E, and K, have shown a good ability to inhibit ferroptosis. For example, vitamin A significantly upregulated the expression of several key ferroptotic gatekeepers genes through nuclear retinoic acid receptors and retinoic X receptors (RAR/RXR). Vitamin B6 could compensate for the impaired glutathione (GSH) levels and restore Glutathione peroxidase 4 (GPX4) expression in cells, ultimately inhibiting ferroptosis. Vitamin D could up-regulate the expression of several anti-ferroptosis proteins by activating vitamin D receptors. Vitamin E and hydroquinone vitamin K (VKH2) can directly inhibit the propagation of lipid peroxidation, thereby inhibiting ferroptosis. In this review, we summarize the currently understood mechanisms by which vitamins inhibit ferroptosis to provide reference information for future research on the development of ferroptosis inhibitors.

The Potential Regulatory Role of Ferroptosis in Orthodontically Induced Inflammatory Root Resorption

People, in increasing numbers, are seeking orthodontic treatment to correct malocclusion, while some of them are suffering from orthodontically induced inflammatory root resorption (OIIRR). Recent evidence suggests that the immune-inflammatory response occurring during bone remodeling may be responsible for OIIRR. Ferroptosis, a new type of programmed cell death (PCD), has been found to have a close interrelation with inflammation during disease progression. While ferroptosis has been extensively studied in bone-related diseases, its role in OIIRR is poorly understood. Considering that the tooth root shares a lot of similar characteristics with bone, it is reasonable to hypothesize that ferroptosis contributes to the development of OIIRR. Nevertheless, direct evidence supporting this theory is currently lacking. In this review, we introduced ferroptosis and elucidated the mechanisms underlying orthodontic tooth movement (OTM) and OIIRR, with a special focus on the pivotal role inflammation plays in these processes. Additionally, we covered recent research exploring the connections between inflammation and ferroptosis. Lastly, we emphasized the important regulatory function of ferroptosis in bone homeostasis. Further investigations are required to clarify the modulation mechanisms of ferroptosis in OIIRR and to develop novel and potential therapeutic strategies for the management of OIIRR.

Osteoblastic ferroptosis inhibition by small-molecule promoting GPX4 activation for peri-prosthetic osteolysis therapy

Peri-prosthesis osteolysis (PPO) represents the most severe complication of total joint arthroplasty (TJA) surgery and imposes the primary cause of prosthesis failure and subsequent revision surgery. Antiresorptive therapies are usually prescribed to treat PPO, especially for elderly people. Nevertheless, the efficacy of anti-osteoporotic medications remains constrained. Recent therapeutic strategies to promote periprosthetic osseointegration by restoring osteoblast function are considered more effective approaches. However, the precise mechanism underlying the inhibition of osteogenesis triggered by wear particles remains enigmatic. Herein, we demonstrate that wear particles inhibit osteoblast function by inducing ferroptosis to sabotage extracellular mineralization and arouse periprosthetic osteolysis. The suppression of ferroptosis could significantly rescue osteogenesis thus alleviating PPO. Furthermore, Glutathione Peroxidase 4 (GPX4) has been identified as a key target in regulating osteoblastic ferroptosis. By utilizing virtual screening techniques, we have successfully conducted a comprehensive screening of a natural compound known as Urolithin A (UA), which exhibits remarkable inhibition of osteoblastic ferroptosis while simultaneously promoting the process of osteogenesis through its precise targeting mechanism on GPX4. Meanwhile, UA improves the osteolytic conditions significantly in vivo even when the adjunction of titanium (Ti) nanoparticles. This strategy has great potential in treating peri-prosthesis osteolysis and potentially broadens the scope of clinical therapy.

Association between diabetes mellitus and trochanteric bone mineral density in individuals with osteoporotic fractures: a retrospective study

Background

The relationship between diabetes mellitus (DM) and bone mineral density (BMD) in patients with osteoporotic fractures (OPFs) remains complex and heterogeneous, specifically between the genders. This study aimed to explore the association between diabetes status and trochanteric BMD in a cohort of patients with OPFs and elucidate the differences between male and female patients.

Methods

This retrospective analysis was performed on 710 admitted patients aged 50 years or older with OPFs. In this study, the exposure variable was diabetes status. Trochanteric BMD comprised the dependent variable. While controlling for covariance influences, generalized estimating equations (GEE) were applied to examine the independent link between diabetes status and trochanteric BMD in OPFs patients. Moreover, a subgroup analysis was also conducted to validate the result's stability.

Results

A substantial positive association was noted between diabetes status and trochanteric BMD in diabetic patients, as determined by the fully adjusted model (β = 0.017, 95% CI 0.001 to 0.033, p = 0.035). Furthermore, the sex-specific analysis showed a significant positive relationship between diabetes status and trochanteric BMD in male patients (β = 0.040, 95% CI 0.006 to 0.075, p = 0.022), whereas no significant relationship was observed in female patients (β = 0.010, 95% CI -0.008 to 0.028, p = 0.256).

Conclusion

This study highlighted the significant sex differences in the impact of diabetes on trochanteric BMD among patients with OPFs. The male diabetic patients had higher trochanteric BMD than their non-diabetic counterparts; however, this association was not evident in female patients. Further research is necessary to understand the underlying mechanisms that contribute to these sex-specific differences and to evaluate the clinical implications of managing fracture risk in diabetic patients.

Nanostructures in Orthopedics: Advancing Diagnostics, Targeted Therapies, and Tissue Regeneration

Nanotechnology, delving into the realm of nanometric structures, stands as a transformative force in orthopedics, reshaping diagnostics, and numerous regenerative interventions. Commencing with diagnostics, this scientific discipline empowers accurate analyses of various diseases and implant stability, heralding an era of unparalleled precision. Acting as carriers for medications, nanomaterials introduce novel therapeutic possibilities, propelling the field towards more targeted and effective treatments. In arthroplasty, nanostructural modifications to implant surfaces not only enhance mechanical properties but also promote superior osteointegration and durability. Simultaneously, nanotechnology propels tissue regeneration, with nanostructured dressings emerging as pivotal elements in accelerating wound healing. As we navigate the frontiers of nanotechnology, ongoing research illuminates promising avenues for further advancements, assuring a future where orthopedic practices are not only personalized but also highly efficient, promising a captivating journey through groundbreaking innovations and tailored patient care.

Amorphous Magnesium Coating for Achieving Functional Changes from Antibacterial to Osteogenic Activities

Medical devices composed of titanium (Ti) should exhibit antibacterial and osteogenic activities to achieve both infection prevention and rapid bone reconstruction. Here, a Ti surface was modified by performing magnetron sputtering (MS) using pure Mg or Mg-30Ca alloy targets for surface functionalization. MC0, prepared with a pure Mg target, had a crystalline metallic-Mg coating layer, whereas MC30, prepared with an Mg-30Ca alloy target, had an amorphous coating composed of Mg and Ca. Both samples rapidly dissolved when immersed in a cell culture medium and exhibited antibacterial activities against methicillin-resistant Staphylococcus aureus and cytotoxicity against MC3T3-E1 cells. Furthermore, MC30 promoted the proliferation and calcification of MC3T3-E1 cells because of the subsequent deposition of calcite on the surface after rapid dissolution. Our findings are the first to reveal that MS performed by using an Mg-30Ca alloy target endowed Ti surfaces with functional changes from antibacterial to osteogenic activities over time. Our results provide fundamental insights into the surface design of Ti-based medical devices for enhanced bone reconstruction and infection prevention and offer possibilities for biomedical applications of Mg-based coatings.

Osteoporotic thoracolumbar spine fractures in the elderly: alterations in GNRI and BMP-2 in delayed union and associated factors

OBJECTIVE

To investigate the alterations in the Geriatric Nutritional Risk Index (GNRI) and bone morphogenetic protein 2 (BMP-2) levels and identify associated factors in older adults with delayed union of osteoporotic thoracolumbar spine fractures.

METHODS

From June 2021 to June 2023, 139 elderly patients with osteoporotic thoracolumbar spine fractures were selected and divided into a delayed group and a normal group according to the fracture healing status at 6 months postoperatively. GNRI and BMP-2 levels were assessed in both cohorts. Receiver operating characteristic (ROC) curves were used to determine the predictive value of GNRI and BMP-2 for delayed union. Multivariate Logistic regression was utilized to identify risk factors associated with delayed union after surgery for osteoporotic thoracolumbar spine fractures. Pearson correlation analysis was conducted to explore the relationships among independent risk factors. Finally, the Generic Quality of Life Inventory-74 (GQOL-74) was employed to assess the quality of life in both groups.

RESULTS

At 6 months post-surgery, 41 of the 139 patients had delayed union and were classified into the delayed group, while 98 cases achieved fracture healing and served as the normal group. The delayed group exhibited obviously reduced GNRI and BMP-2 levels than the normal group. ROC curve analysis indicated that the areas under the curve (AUCs) of GNRI, BMP-2, and their combination for predicting delayed union were 0.826, 0.803, and 0.883, respectively. A higher recovery rate of the injured vertebra height (OR = 1.456, 95% CI: 1.232-1.722, P < 0.001), a lower GNRI (OR = 0.590, 95% CI: 0.444-0.782, P < 0.001), and a lower BMP-2 level (OR = 0.909, 95% CI: 0.850-0.971, P = 0.005) were independent risk factors for delayed union in elderly patients undergoing surgery for osteoporotic thoracolumbar spine fractures. Pearson correlation analysis showed a negative correlation between the recovery rate of the injured vertebra height and GNRI (r = -0.640) as well as BMP-2 (r = -0.614), and a positive correlation between GNRI and BMP-2 (r = 0.751). Although the postoperative quality of life in the delayed group significantly enhanced, it remained significantly lower than that in the normal group.

CONCLUSIONS

Delayed union after surgery in elderly patients with osteoporotic thoracolumbar spine fractures is strongly associated with preoperative levels of GNRI and BMP-2. The recovery rate of the injured vertebra height, GNRI, and BMP-2 are independent risk factors for delayed fracture healing. Delayed healing of osteoporotic thoracolumbar spine fractures in the elderly negatively affects the improvement of patients' quality of life.

Knee osteotomy combined with meniscal allograft transplantation versus knee osteotomy alone in patients with unicompartmental knee osteoarthritis: a prospective double-blind randomised controlled trial protocol

INTRODUCTION

Knee osteotomy combined with meniscal allograft transplantation (MAT) showed promising results to treat unicompartmental knee osteoarthritis (OA) secondary to meniscal deficiency and knee malalignment. However, there is still no high-level evidence to demonstrate whether the combination of these two treatments is superior to osteotomy alone.

METHODS AND ANALYSIS

52 patients with unicompartmental knee OA Kellgren-Lawrence grade ≤3 secondary to meniscal deficiency and knee malalignment (aged 20-60 years) are randomised to undergo knee osteotomy associated with MAT or knee osteotomy alone in a 1:1 ratio. The primary outcome is the International Knee Documentation Committee (IKDC) subjective score at 12 months. The secondary outcomes are the IKDC subjective score at 1, 3 and 6 months, the Western Ontario and McMaster Universities Osteoarthritis Index score, the Knee Injury and Osteoarthritis Outcome Score, the Visual Analogue Scale, the EuroQol Visual Analogue Scale, the Tegner Activity Level Scale, objective parameters (transpatellar circumference, suprapatellar circumference and range of motion), patient expectation on treatment efficacy and patient satisfaction at 1, 3, 6 and 12 months. Radiographs are performed at baseline and at 1-, 6- and 12-month follow-ups and magnetic resonance evaluations at baseline and at 12 months. Biomechanical assessment is performed through gait analysis before surgery and at 12 months, investigating motion data, biomechanical parameters and muscle activation through electromyography. In addition, to detect early joint environment changes and potential MAT effects in protecting the articular surface providing a better knee homeostasis, biological markers of cartilage turnover and inflammation obtained from synovial fluid, serum and urine are evaluated at baseline and at 24 hours, 1-, 3-, 6- and 12-month follow-ups.

ETHICS AND DISSEMINATION

The study protocol has been approved by Emilia Romagna's Ethics Committee (CE-AVEC), Bologna, Italy. Written informed consent is obtained from all participants. Findings of this study will be disseminated through peer-reviewed publications and conference presentations.

PROTOCOL VERSION

March 2023.

TRIAL REGISTRATION NUMBER

NCT05840887.

Relationship Between the Subchondral Trabecular Bone Microstructure in the Hip Joint and Pain in Patients with Hip Osteoarthritis

OBJECTIVE

This study aimed to investigate the relationship between clinical findings and the trabecular microstructure of the subchondral bone in patients with hip osteoarthritis (OA) due to developmental dysplasia of the hip (DDH) using multidetector row computed tomography (MDCT).

DESIGN

A total of 63 patients (69 hips) with OA due to DDH were retrospectively reviewed, with 12 healthy controls being included for comparison. Clinical evaluation was performed using the Japanese Orthopaedic Association Hip Disease Evaluation Questionnaire (JHEQ). The trabecular bone microstructure was analyzed using MDCT. Regions of interest in the subchondral trabecular bones of the acetabulum and femoral head were defined in the coronal view, and various trabecular microstructural parameters were evaluated.

RESULTS

Bone volume fraction (BV/TV) and trabecular thickness (Tb.Th) exhibited a significant positive correlation with the OA stage, whereas trabecular separation (Tb.Sp) showed a negative correlation. In addition, BV/TV and Tb.Th were negatively correlated with the JHEQ total and pain scores, whereas Tb.Sp was positively correlated with the pain score in all regions.

CONCLUSIONS

This is the first study to evaluate the bone microstructure and its relationship with clinical findings in patients with hip OA due to DDH. Our findings suggest that as OA progresses, osteosclerotic changes increase in the acetabulum and femoral head; these changes are associated with worsening clinical symptoms, particularly pain. Targeting the subchondral bone may emerge as a novel treatment strategy for patients with OA due to DDH; nevertheless, further comprehensive studies are required.

Asperosaponin VI inhibition of DNMT alleviates GPX4 suppression-mediated osteoblast ferroptosis and diabetic osteoporosis

INTRODUCTION

Diabetic osteoporosis (DOP) is an insidious complication of diabetes with limited therapeutic options. DOP is pathologically associated with various types of regulated cell death, but the precise role of ferroptosis in the process remains poorly understood. Asperosaponin VI (AVI), known for its clinical efficacy in treating bone fractures and osteoporosis, may exert its osteoprotective effects through mechanisms involving ferroptosis, however this has not been established.

OBJECTIVES

This study aimed to investigate the role of AVI in modulating ferroptosis in a mouse model of DOP and to explore the underlying mechanisms.

METHODS

We assessed OP alterations in femurs of DOP-conditioned mice and primary bone cells. We generated a strain of osteoblast-specific Gpx4-deficient mice. A combination of micro-CT, immunohistochemistry, immunofluorescence, methylation-specific PCR (MSP), bisulfite sequencing PCR (BSP), western blotting (WB), and AVI pull-down assays were employed to elucidate the mechanism and therapeutic target of AVI in DOP.

RESULTS

Our findings revealed that femurs from DOP-conditioned mice exhibited significant ferroptosis and suppression of the core anti-ferroptosis factor GPX4, mainly due to hypermethylation of the Gpx4 promoter mediated by DNA methyltransferases DNMT1and DNMT3a. Notably, treatment with AVI effectively reversed the hypermethylation, restored GPX4 expression, and reduced ferroptotic pathologies associated with DOP by inhibiting DNMT1/3a. In primarily-cultured osteoblasts and osteoclasts, AVI alleviated GPX4 suppression and reduced ferroptosis in DOP-conditioned osteoblasts through a mechanism dependent on DNMT inhibition and GPX4 restoration. Importantly, the anti-ferroptotic and osteoprotective effects of AVI were abolished in osteoblastic Gpx4 haplo-deficient mice (Gpx4Ob-/+) or when GPX4 was pharmacologically inactivated with RSL3.

CONCLUSIONS

Our study identifies a pivotal epigenetic ferroptotic pathway that contributes significantly to DOP and uncovers a crucial pharmacological property of AVI that is potentially effective in treating patients with DOP and related osteoporotic disorders.

Decoding ferroptosis: transforming orthopedic disease management

As a mechanism of cell death, ferroptosis has gained popularity since 2012. The process is distinguished by iron toxicity and phospholipid accumulation, in contrast to autophagy, apoptosis, and other cell death mechanisms. It is implicated in the advancement of multiple diseases across the body. Researchers currently know that osteosarcoma, osteoporosis, and other orthopedic disorders are caused by NRF2, GPX4, and other ferroptosis star proteins. The effective relief of osteoarthritis symptoms from deterioration has been confirmed by clinical treatment with multiple ferroptosis inhibitors. At the same time, it should be reminded that the mechanisms involved in ferroptosis that regulate orthopedic diseases are not currently understood. In this manuscript, we present the discovery process of ferroptosis, the mechanisms involved in ferroptosis, and the role of ferroptosis in a variety of orthopedic diseases. We expect that this manuscript can provide a new perspective on clinical diagnosis and treatment of related diseases.

Corrosion behavior, antibacterial properties and in vitro and in vivo biocompatibility of biodegradable Zn-5Cu-xMg alloy for bone-implant applications

Reasonable optimization of degradation rate, antibacterial performance and biocompatibility is crucial for the development of biodegradable zinc alloy medical implant devices with antibacterial properties. In this study, various amounts of Mg elements were incorporated into Zn5Cu alloy to modulate the degradation rate, antibacterial properties and biocompatibility. The effects of Mg contents on the microstructure, corrosion behavior, antibacterial properties and biocompatibility of Zn-5Cu-xMg alloy were extensively investigated. The results revealed that with an increase of Mg content, the amount of Mg2Zn11 phase increased and its galvanic effect with the Zn matrix was enhanced, which accelerated the corrosion process and led to higher corrosion rate and high degradation rate of the alloy. Additionally, there was an increased release of Mg2+ and Zn2+ ions from the alloy which imparted excellent resistance against Escherichia coli and Staphylococcus aureus bacteria and improved biocompatibility, subcutaneous antibacterial and immune microenvironment regulation properties. Zn-5Cu-2 Mg exhibited superior antibacterial ability, cell compatibility, proliferation effect, subcutaneous antibacterial and immune microenvironment regulation performances, which can work as a promising candidate of biodegradable antibacterial medical implants.

Action Programmed Nanoantibiotics with pH-Induced Collapse and Negative-Charged-Surface-Induced Deformation against Antibiotic-Resistant Bacterial Peritonitis

The incorporation of well-designed antibiotic nanocarriers, along with an antibiotic adjuvant effect, in combination with various antibiotics, offers an opportunity to combat drug-resistant strains. However, precise control over morphology and encapsulated payload release can significantly impact their antibacterial efficacy and synergistic effects when used alongside antibiotics. Here, this study focuses on developing lipopeptide-based nanoantibiotics, which demonstrate an antibiotic adjuvant effect by inducing pH-induced collapse and negative-charged-surface-induced deformation. This enhances the disruption of the bacterial outer membrane and facilitates drug penetration, effectively boosting the antimicrobial activity against drug-resistant strains. The modulation regulations of the lipopeptide nanocarriers with modular design are governed by the authors. The nanoantibiotics, made from lipopeptide and ciprofloxacin (Cip), have a drug loading efficiency of over 80%. The combination with Cip results in a significantly low fractional inhibitory concentration index of 0.375 and a remarkable reduction in the minimum inhibitory concentration of Cip against multidrug-resistant (MDR) Escherichia coli (clinical isolated strains) by up to 32-fold. The survival rate of MDR E. coli peritonitis treated with nanoantibiotics is significantly higher, reaching over 87%, compared to only 25% for Cip and no survival for the control group. Meanwhile, the nanoantibiotic shows no obvious toxicity to major organs.

Assessing sarcoma cell cytoskeleton remodeling in response to varying collagen concentration

Sarcomas, rare malignant tumors of mesenchymal origin, are often underdiagnosed and have face diagnostic ambiguities and limited treatment options. The main objective of this study was to define the nanomechanical and biophysical properties of sarcoma cells, particularly examining how the cytoskeleton's remodeling and related cellular processes such as cell migration and invasion in response to environmental stimuli due to collagen content. Utilizing one murine fibrosarcoma and one osteosarcoma cell line we employed atomic force microscopy, immunostaining, advanced image processing, in vitro cellular assays, and molecular techniques to investigate cells' cytoskeleton remodeling in response to varying collagen concentration. Our study focused on how alterations in collagen content affects the cytoskeletal dynamics and correlate with changes in gene expression profiles relevant to metastasis and an aggressive cancer phenotypes. Our findings indicate that despite their shared classification, fibrosarcoma and osteosarcoma cells display distinct biophysical properties and respond differently to mechanical forces. Notably, this difference in cellular behavior renders mechanical properties a potent novel biomarkers. Furthermore, the metastasis-related identified genes related to metastatic capability, could be potential therapeutic targets. This study highlights the significance of understanding the unique traits of sarcoma cells to improve diagnostic precision and expand therapeutic strategies, for this rare type of cancer.

Scalable fabrication of freely shapable 3D hierarchical Cu-doped hydroxyapatite scaffolds via rapid gelation for enhanced bone repair

Critical-sized bone defects present a formidable challenge in tissue engineering, necessitating innovative approaches that integrate osteogenesis and angiogenesis for effective repair. Inspired by the hierarchical porous structure of natural bone, this study introduces a novel method for the scalable production of ultra-long, copper-doped hydroxyapatite (Cu-HAp) fibers, utilizing the rapid gelation properties of guar gum (GG) under controlled conditions. These fibers serve as foundational units to fabricate three-dimensional porous scaffolds with a biomimetic hierarchical architecture. The scaffolds exhibit a broad pore size distribution (1-500 μm) and abundant nanoporous features, mimicking the native bone extracellular matrix. Physicochemical characterization and in vitro assays demonstrated that the copper doping significantly enhanced osteogenic and angiogenic activities, with optimized concentrations (0.8 % and 1.2 % Cu) facilitating the upregulation of osteogenesis-related genes and proteins, as well as promoting endothelial cell proliferation. In vivo studies further confirmed the scaffolds' efficacy, with the 1.2Cu-HAp group showing a remarkable increase in bone regeneration (bone volume/total volume ratio: 35.7 ± 1.87 %) within the defect site. This research offers a promising strategy for the rapid fabrication of multifunctional scaffolds that not only support bone tissue repair but also actively accelerate the healing process through enhanced vascularization.

Irisin in degenerative musculoskeletal diseases: Functions in system and potential in therapy

Degenerative musculoskeletal diseases are a class of diseases related to the gradual structural and functional deterioration of muscles, joints, and bones, including osteoarthritis (OA), osteoporosis (OP), sarcopenia (SP), and intervertebral disc degeneration (IDD). As the proportion of aging people around the world increases, degenerative musculoskeletal diseases not only have a multifaceted impact on patients, but also impose a huge burden on the medical industry in various countries. Therefore, it is crucial to find key regulatory factors and potential therapeutic targets. Recent studies have shown that irisin plays an important role in degenerative musculoskeletal diseases, suggesting that it may become a key molecule in the prevention and treatment of degenerative diseases of the musculoskeletal system. Therefore, this review provides a comprehensive description of the release and basic functions of irisin, and summarizes the role of irisin in OA, OP, SP, and IDD from a cellular and tissue perspective, providing comprehensive basis for clinical application. In addition, we summarized the many roles of irisin as a key information molecule in bone-muscle-adipose crosstalk and a regulatory molecule involved in inflammation, senescence, and cell death, and proposed the interesting possibility of irisin in degenerative musculoskeletal diseases.

Contribution of macrophage polarization in bone metabolism: A literature review

Macrophage polarization divides macrophages into two main cell subpopulations, classically and alternatively activated macrophages (M1 and M2, respectively). M1 polarization promotes osteoclastogenesis, while M2 polarization promotes osteogenesis. The physiological homeostasis of bone metabolism involves a high dynamic balance between osteoclastic-mediated bone resorption and formation. Reportedly, M1/M2 imbalance causes the onset and persistence of inflammation-related bone diseases. Therefore, understanding the research advances in functions and roles of macrophages in such diseases will provide substantial guidance for improved treatment of bone diseases. In this review, we underscore and summarize the research advances in macrophage polarization, and bone-related diseases, such as rheumatoid arthritis, osteoarthritis, and osteoporosis, over the last 5 years. Our findings showed that targeting macrophages and balancing macrophage polarization can effectively reduce inflammation and decrease bone destruction while promoting bone formation and vascular repair. These results indicate that regulating macrophage and macrophage polarization to restore homeostasis is a prospective approach for curing bone-related diseases.

Nanomaterials: Recent Advances in Knee Osteoarthritis Treatment

Osteoarthritis (OA) of the knee is the most prevalent degenerative joint condition that places a substantial financial and medical burden on society. However, due to drawbacks such as inefficiency, adverse effects, and brief duration of action, the clinical efficacy of the current major therapies for knee OA is largely restricted. Therefore, novel medication development is highly required to address these issues. Numerous studies in recent years have established that nanomaterials can be a potential and highly effective way to overcome these challenges. In this review, the anatomical distinctions between healthy and OA knee joints, as well as novel advances in the field of nanomaterials for the treatment of knee OA are summarized. The limits of the present therapeutic strategies for treating knee OA are also highlighted, as well as the potential prospects of nanomaterials in the future.

Extracellular matrix-mimicking cryogels composed of methacrylated fucoidan enhance vascularized skeletal muscle regeneration following volumetric muscle loss

Volumetric muscle loss (VML) significantly impairs the inherent regenerative ability of skeletal muscle and results in chronic functional impairment. Polysaccharides in the muscle extracellular matrix are crucial for regulating cell proliferation and differentiation. Recent studies indicate that fucoidan has beneficial effects on musculoskeletal conditions. However, the impact of fucoidan on skeletal muscle regeneration remains poorly understood. In this study, methacrylated fucoidan (FuMA) was synthesized through chemical grafting of the methacryloyl group onto fucoidan. In vitro experiments demonstrated that treatment with FuMA significantly up-regulated the expression of myogenic markers and promoted the formation of myotubes in C2C12 myoblast cells. Importantly, FuMA treatment led to a significant enhancement in mitochondrial energy metabolism of myoblasts via activation of the NRF2 antioxidant signaling pathway. To further investigate the regenerative properties in repairing skeletal muscle defects, we fabricated a dual crosslinked cryogel consisting of FuMA and methacrylated gelatin (GelMA) with a porous and interconnected structure. In a rat tibialis anterior muscle VML model, implantation of the FuMA/GelMA cryogel effectively promoted the regeneration of muscle fibers, reduced collagen deposition, and facilitated the formation of new blood vessels. Hence, polysaccharide-based cryogels represent a promising implantable biomimetic scaffold for facilitating skeletal muscle regeneration following severe injuries.

Prodigiosin hydrogel to promote healing of trauma-infected multidrug-resistant Staphylococcus aureus mice wounds

Wound infections caused by Multidrug-resistant Staphylococcus aureus (MRSA) have been regarded as a challenging problem in clinic for the long time. In this study, based on the excellent antimicrobial effect of prodigiosin(PG) and the ability of hydrogel dressing in terms of tissue repair and regeneration, we prepared the PG hydrogel as a treatment for the wound infection induced by MRSA. Rheological tests indicated that PG hydrogel as a semi-solid gel had good mechanical properties. In ex vitro drug permeation studies and dermatokinetic studies showed that PG hydrogel had high PG permeability and were capable of short-term retention in the skin. In addition, in vivo experiments for mouse skin wounds showed that the serum levels of inflammatory factors including IL-β and other inflammatory factors were reduced, the inflammatory infiltration of tissues was reduced, the transcript levels of genes such as COL1A1 were up-regulated at different stages of wound healing, and the relative abundance of genera such as Desulfovibrio was lowered after treatment with PG hydrogel, which facilitated wound healing in mice. Our study would provide a new solution to the clinical shortage of drugs for the treatment of MRSA infection and provide a research basis for improving the comprehensive values of PG.

Total Knee Arthroplasty in Patients With Ankle Osteoarthritis Affects Contralateral Ankle Alignment and Postoperative Outcome of Total Knee Arthroplasty

BACKGROUND

This study investigated the impact of total knee arthroplasty (TKA) on the alignment of the ankle joint, focusing on changes in coronal alignment of both ankles.

METHODS

This retrospective study, conducted at our hospital, included 64 patients older than 70 years who underwent TKA for varus knee osteoarthritis (OA). Using full-length standing radiographs of both lower extremities taken preoperatively and 6 months postoperatively, we assessed ankle OA grading based on the Takakura-Tanaka classification and measured mechanical hip-knee-ankle (mHKA) and the tibiotalar angle (TTA) on both the surgical and contralateral side. Additionally, we examined the impact of ankle OA on postoperative clinical scores, the Knee injury and Osteoarthritis Outcome Score, following TKA.

RESULTS

Based on the classification, ankle OA stage 2 or higher was present in 13 cases on the surgical side and 13 cases on the contralateral side. On the surgical side, mHKA changed from 12.2 to 1.8 degrees varus (P < .001) and TTA from 1.7 to 1.0 degrees varus (P = .002). On the contralateral side, mHKA changed from 4.0 to 5.4 degrees varus (P = .04), and TTA from 2.7 to 3.0 degrees varus (P < .001). In ankle OA stage 2 or higher patients, contralateral TTA changed from 5.2 to 6.5 degrees varus (P < .001) and unchanged in stage 1 patients. Ankle OA stage 2 or higher patients had worse ADL outcomes than stage 1 patients (score: 67.2 and 78.3, respectively, P = .03).

CONCLUSION

This study suggests an apparent interrelationship between knee and ankle OA and the potential negative influence of TKA on ankle OA.

Advances in the study of polysaccharides from Anemarrhena asphodeloides Bge.: A review

Anemarrhena asphodeloides Bge. (AA), a traditional Chinese medicine, is used clinically to treat inflammation, diabetes, osteoporosis, and tumors. Polysaccharides are the most abundant components in AA, and have antioxidant, immunomodulatory, anti-inflammatory, hypoglycemic, anti-osteoporosis, and laxative effects. It is necessary to conduct a comprehensive analysis on the structure and pharmacological activity of the polysaccharides from AA (PAAs). This review systematically summarizes the structural characteristics of PAAs, including the monosaccharide compositions, molecular weights, and backbone structures. We discuss the relationship between the structure and pharmacological activities of PAAs. The chemical modification methods of PAAs, including zinc chelation, carboxymethylation, and sulfation, are then reviewed. This review may offer new insights for research on the PAAs and polysaccharides with similar structures.

Poor bone health in Duchenne muscular dystrophy: a multifactorial problem beyond corticosteroids and loss of ambulation

Duchenne muscular dystrophy (DMD) is a progressive, fatal muscle wasting disease caused by X-linked mutations in the dystrophin gene. Alongside the characteristic muscle weakness, patients face a myriad of skeletal complications, including osteoporosis/osteopenia, high susceptibility to vertebral and long bone fractures, fat embolism post-fracture, scoliosis, and growth retardation. Those skeletal abnormalities significantly compromise quality of life and are sometimes life-threatening. These issues were traditionally attributed to loss of ambulation and chronic corticosteroid use, but recent investigations have unveiled a more intricate etiology. Factors such as vitamin D deficiency, hormonal imbalances, systemic inflammation, myokine release from dystrophic muscle, and vascular dysfunction are emerging as significant contributors as well. This expanded understanding illuminates the multifaceted pathogenesis underlying skeletal issues in DMD. Present therapeutic options are limited and lack specificity. Advancements in understanding the pathophysiology of bone complications in DMD will offer promising avenues for novel treatment modalities. In this review, we summarize the current understanding of factors contributing to bone problems in DMD and delineate contemporary and prospective multidisciplinary therapeutic approaches.

Therapeutic potential of hesperidin in diabetes mellitus-induced erectile dysfunction through Nrf2-mediated ferroptosis and oxidative stress

BACKGROUND

Among erectile dysfunction (ED) caused by metabolic abnormalities, diabetes mellitus-induced ED (DMED) progresses rapidly, manifests with severe symptoms, and shows reduced responsiveness to conventional medications. Hyperglycemia in the corpus cavernosum has been linked to the induction of both ferroptosis and oxidative stress, which are mediated by nuclear factor E2 related factor 2 (Nrf2). Hesperidin (Hes), a flavonoid compound, has been revealed to activate Nrf2 in certain diabetic complications, yet the efficacy of Hes on DMED and the specific mechanism remain unclear.

OBJECTIVES

To elucidate the potential mechanism and efficacy of Hes in regulating Nrf2-mediated ferroptosis and oxidative stress in DMED.

MATERIALS AND METHODS

DMED rats were constructed through the intraperitoneal injection of streptozotocin (STZ), partially supplemented with Hes. In parallel, in vitro research utilized human umbilical vein endothelial cells (HUVECs), with glucose addition to simulating a high glucose (HG) environment, and induced with Hes or ML385 (an Nrf2 inhibitor). Penile tissues and HUVECs were harvested for subsequent analyses.

RESULTS

The results of this study indicate that Hes partially reversed the impaired erectile function. The expression of Nrf2, glutathione peroxidase 4 (GPX4), and heme oxygenase-1 (HO-1) in the corpus cavernosum elevated after supplementing with Hes, resulted in an inhibition in ferroptosis and oxidative stress. Moreover, the quantity and function of erectile effector cells were restored, and cavernous fibrosis was ameliorated. In HG-induced HUVECs, Hes ameliorated Nrf2-mediated ferroptosis and oxidative stress, effects which ML385 partially reversed.

CONCLUSIONS

Hes exerts a therapeutic effect on DMED rats and a regulatory mechanism on the Nrf2-HO-1/GPX4 axis, concurrently revitalizing endothelial and smooth muscle cells, and diminishing fibrosis. Our study provides robust preclinical evidence for employing Hes in treating DMED.

TIMP1 regulates ferroptosis in osteoblasts by inhibiting TFRC ubiquitination: an in vitro and in vivo study

BACKGROUND

In clinical practice, alterations in the internal environment of type 2 diabetes can significantly affect bone quality. While the increased risk of fractures among diabetic patients is well-established, the precise mechanisms by which hyperglycemia influences bone quality remain largely unclear.

METHODS

Western blotting, immunohistochemistry (IHC), and micro-CT were used to examine ferroptosis-related protein expression and bone morphology changes in the bone tissues of type 2 diabetic mice. The CCK8 assay determined the optimal conditions for inducing ferroptosis in osteoblasts by high glucose and high fat (HGHF). Ferroptosis phenotypes in osteoblasts were analyzed using flow cytometry, Western blotting, and two-photon laser confocal microscopy. Transcriptomic sequencing of the control and HGHF groups, followed by bioinformatic analysis, identified and validated key genes. TIMP1 was knocked down in osteoblasts to assess its impact on ferroptosis, while TFRC expression was inhibited and activated to verify the role of TIMP1 in regulating ferroptosis through TFRC. The therapeutic effect of TIMP1 inhibition on osteoporosis was evaluated in a type 2 diabetic mouse model.

RESULTS

The expression of TIMP1 is increased in type 2 diabetic osteoporosis. In vitro, TIMP1 knockout inhibited ferroptosis in osteoblasts induced by high glucose and high fat (HGHF). However, overexpression of TFRC reversed the ferroptosis inhibition caused by TIMP1 knockout. Suppression of TIMP1 expression alleviated the progression of osteoporosis in type 2 diabetic mice. Mechanistic studies suggest that TIMP1 regulates HGHF-induced ferroptosis in osteoblasts through TFRC.

CONCLUSION

This study demonstrates that TIMP1 expression is increased during type 2 diabetic osteoporosis and that TIMP1 promotes ferroptosis in osteoblasts by regulating TFRC. These findings suggest that TIMP1 is a promising novel therapeutic target for type 2 diabetic osteoporosis.

Role and Mechanism of Mechanical Load in the Homeostasis of the Subchondral Bone in Knee Osteoarthritis: A Comprehensive Review

Osteoarthritis (OA) is one of the most prevalent degenerative joint diseases, and the knee joint is particularly susceptible to it. It typically affects the entire joint and is marked by the erosion of cartilage integrity, chondrocytopenia, subchondral bone sclerosis and the mild synovial inflammation. Pathological changes in the subchondral bone often serve as initiating factors for joint degeneration. Various predisposing factors, including metabolic disorders, oxidative stress, and abnormal mechanical loading, regulate OA pathogenesis. Of them, mechanical loading is closely associated with the maintenance of the subchondral bone. Disrupted mechanical loading, leading to subchondral bone remodeling, can potentially trigger OA, whereas appropriate loading might ameliorate its progression. Therefore, this narrative review aimed to discuss existing knowledge and explore how mechanical loading mediates changes in the subchondral bone, influencing the development of knee osteoarthritis. Special emphasis is placed on its role and underlying mechanisms in maintaining joint homeostasis.

Recent advances in mesoporous silica nanoparticles formulations and drug delivery for wound healing

Wound healing is a natural process that can be disrupted by disease. Nanotechnology is a promising platform for the development of new therapeutic agents to accelerate acute and chronic wound healing. Drug delivery by means of nanoparticles as well as wound dressings have emerged as suitable options to improving the healing process. The characteristics of mesoporous silica nanoparticles (MSNs) make them efficient carriers of pharmaceutical agents alone or in combination with dressings. In order to maximize the effect of a drug and minimize its adverse consequences, it may be possible to include targeted and intelligent release of the drug into the design of MSNs. Its use to facilitate closure of adjacent sides of a cut as a tissue adhesive, local wound healing, controlled drug release and induction of blood coagulation are possible applications of MSNs. This review summarizes research on MSN applications for wound healing. It includes a general overview, wound healing phases, MSN formulation, therapeutic possibilities of MSNs and MSN-based drug delivery systems for wound healing.

An acidity-triggered aggregation nanoplatform based on degradable mesoporous organosilica nanoparticles for precise drug delivery and phototherapy of focal bacterial infection

It is crucial to precisely strike the bacterially infected area and avoid damaging healthy tissue in bacterial infection treatment. Herein, we report an acidity-triggered aggregation antibacterial nanoplatform based on biodegradable mesoporous organic silica nanoparticles (MON NPs). The surface of MON NPs modified with polydopamine (PDA) encapsulated ciprofloxacin (CIP) and methylene blue (MB) and was then further grafted with glycol chitosan to obtain MB/CIP@MON-PDA-GCS NPs (MCMPG NPs). In the bacterial infection environment with acidic characteristics, glycol chitosan (GCS) becomes positively charged. Consequently, the positively charged acidity-triggered GCS enables MCMPG NPs to accumulate on the negatively charged bacterial surfaces in the infected area and not in healthy tissue. The targeted method allows for the precise release of CIP and MB, ensuring the spatial accuracy of photodynamic therapy (PDT) and photothermal therapy (PTT) for effective bacteria-specific treatment.

The immediate ex vivo covering and filling characteristics of antibiotic-loaded resorbable calcium sulfate paste around intramedullary nails

Background: Antibiotic-laden polymethyl methacrylate (PMMA)-coated intramedullary nails (IMNs) are an effective treatment for osteomyelitis, but they pose multiple disadvantages. Antibiotic-loaded resorbable calcium sulfate (ARCS) paste is an alternative option to deliver a local antibiotic depot around IMNs, but such use has been minimally investigated. This study aimed to define the immediate covering and filling characteristics of ARCS around IMNs by using anatomic bone models. Method: Five tibia models (foam with cortical shell) were prepared by reaming a uniform 13 mm cylindrical path. Three 40 cc kits of ARCS (STIMULAN, Biocomposites Ltd, Keele, UK) were mixed with 3 g vancomycin and 1.2 g tobramycin powder and injected into the intramedullary canal while wet, completely filling the canal. A 10 mm × 345 mm tibial IMN was immediately inserted without interlocking screws and allowed to completely cure for 2 h. The models were then longitudinally cut without disrupting the dry ARCS covering on the nail. The ARCS was removed from the nail at five equidistant locations along the nail. The thickness of the ARCS was measured with a caliper. A repeated-measures ANOVA test was used to compare the mean width of each segment for each model. Results: In all five trials, the tibial canal volume surrounding the nail remained completely filled. The ARCS paste was confluent along the length of the IMN. There were no gaps or air pockets between the paste and reamed model bone. There was no statistically significant difference among the five samples at each location ( p = 0.913 ) or among the five locations along the bone ( p = 0.210 ). Conclusion: In a model setting, ARCS fully fills the intramedullary canal of a tibia and covers an IMN uniformly. Study of the in vivo material properties of ARCS may further elucidate the bone penetration as well as the clinical utility of this antibiotic depot technique.

Fabrication and performance of Zinc-based biodegradable metals: From conventional processes to laser powder bed fusion

Zinc (Zn)-based biodegradable metals (BMs) fabricated through conventional manufacturing methods exhibit adequate mechanical strength, moderate degradation behavior, acceptable biocompatibility, and bioactive functions. Consequently, they are recognized as a new generation of bioactive metals and show promise in several applications. However, conventional manufacturing processes face formidable limitations for the fabrication of customized implants, such as porous scaffolds for tissue engineering, which are future direction towards precise medicine. As a metal additive manufacturing technology, laser powder bed fusion (L-PBF) has the advantages of design freedom and formation precision by using fine powder particles to reliably fabricate metallic implants with customized structures according to patient-specific needs. The combination of Zn-based BMs and L-PBF has become a prominent research focus in the fields of biomaterials as well as biofabrication. Substantial progresses have been made in this interdisciplinary field recently. This work reviewed the current research status of Zn-based BMs manufactured by L-PBF, covering critical issues including powder particles, structure design, processing optimization, chemical compositions, surface modification, microstructure, mechanical properties, degradation behaviors, biocompatibility, and bioactive functions, and meanwhile clarified the influence mechanism of powder particle composition, structure design, and surface modification on the biodegradable performance of L-PBF Zn-based BM implants. Eventually, it was closed with the future perspectives of L-PBF of Zn-based BMs, putting forward based on state-of-the-art development and practical clinical needs.

NRF2 in age-related musculoskeletal diseases: Role and treatment prospects

The NRF2 pathway is a metabolic- and redox-sensitive signaling axis in which the transcription factor controls the expression of a multitude of genes that enable cells to survive environmental stressors, such as oxidative stress, mainly by inducing the expression of cytoprotective genes. Basal NRF2 levels are maintained under normal physiological conditions, but when exposed to oxidative stress, cells activate the NRF2 pathway, which is crucial for supporting cell survival. Recently, the NRF2 pathway has been found to have novel functions in metabolic regulation and interplay with other signaling pathways, offering novel insights into the treatment of various diseases. Numerous studies have shown that targeting its pathway can effectively investigate the development and progression of age-related musculoskeletal diseases, such as sarcopenia, osteoporosis, osteoarthritis, and intervertebral disc degeneration. Appropriate regulation of the NRF2 pathway flux holds promise as a means to improve musculoskeletal function, thereby providing a new avenue for drug treatment of age-related musculoskeletal diseases in clinical settings. The review summarized an overview of the relationship between NRF2 and cellular processes such as oxidative stress, apoptosis, inflammation, mitochondrial dysfunction, ferroptosis, and autophagy, and explores the potential of targeted NRF2 regulation in the treatment of age-related musculoskeletal diseases.

A two-pronged approach to inhibit ferroptosis of MSCs caused by the iron overload in postmenopausal osteoporosis and promote osseointegration of titanium implant

Postmenopausal osteoporosis (PMOP) is a prevalent condition among elderly women. After menopause, women exhibit decreased iron excretion, which is prone to osteoporosis. To design a specific titanium implant for PMOP, we first analyze miRNAs and DNA characteristics of postmenopausal patients with and without osteoporosis. The results indicate that iron overload disrupts iron homeostasis in the pathogenesis of PMOP. Further experiments confirm that iron overload can cause lipid peroxidation and ferroptosis of MSCs, thus breaking bone homeostasis. Based on the findings above, we have designed a novel Ti implant coated with nanospheres of caffeic acid (CA) and deferoxamine (DFO). CA can bind on the Ti surface through the two adjacent phenolic hydroxyls and polymerize into polycaffeic acid (PCA) dimer, as well as the PCA nanospheres with the repetitive 1,4-benzodioxan units. DFO was grafted with PCA through borate ester bonds. The experimental results showed that modified Ti can inhibit the ferroptosis of MSCs in the pathological environment of PMOP and promote osseointegration in two main ways. Firstly, DFO was released under high oxidative stress, chelating with excess iron and decreasing the labile iron pool in MSCs. Meanwhile, CA and DFO activated the KEAP1/NRF2/HMOX1 pathway in MSCs and reduced the level of intracellular lipid peroxidation. So, the ferroptosis of MSCs is inhibited by promoting the SLC7A11/GSH/GPX4 pathway. Furthermore, the remained CA coating on the Ti surface could reduce the extracellular oxidative stress and glutathione level. This study offers a novel inspiration for the specific design of Ti implants in the treatment of PMOP.

Ferroptosis involvement in the neurotoxicity of flunitrazepam in zebrafish

In recent years, psychoactive drugs such as benzodiazepines (BZDs) have been frequently detected in water environments, however, there is still limited understanding regarding their potential impact on neurological health and underlying mechanisms. This study evaluated the neurotoxicity of the typical BZD drug flunitrazepam (FLZ, 0.2 and 5 μg/L) in zebrafish embryos and adults, and investigated the relationship between ferroptosis and FLZ-induced neurotoxicity. The results indicated that acute exposure to FLZ significantly inhibited zebrafish embryo hatching and promotes death, induced larval deformities, and led to abnormal neurobehavioral responses in larvae, likely due to ferroptosis induction. Results from a 30-day subacute exposure to FLZ showed that it decreased motor function and induced cognitive impairment in adult zebrafish. Immunofluorescence of brain tissues revealed a reduction in neurons in the telencephalon and an increase in microglia in the mesencephalon of the zebrafish exposed to FLZ. The ultrastructure of brain mitochondria showed serious damage. Besides, FLZ exposure increased iron levels, reduced GSH/GSSG and increased LPO in brain tissue, which is related to the abnormal expression of genes associated with ferroptosis. In the rescue experiments with co-exposure to deferoxamine (DFO), the motor-related parameters and biochemical indexes related to ferroptosis were restored, suggesting that FLZ can induce ferroptosis. The molecular docking results indicated that FLZ had a higher affinity with transferrin. This study elucidates the close relationship between ferroptosis and FLZ-induced neurotoxicity, which is significant for understanding the physiological damage caused by psychoactive substances and assessing environmental risks.

Unveiling the macrophage dynamics in osteoarthritic joints: From inflammation to therapeutic strategies

Osteoarthritis (OA) is an incurable, painful, and debilitating joint disease affecting over 500 million people worldwide. The OA joint tissues are infiltrated by various immune cells, particularly macrophages, which are able to induce or perpetuate inflammation. Notably, synovitis and its macrophage component represent a target of interest for developing treatments. In this review, we describe the latest advances in understanding the heterogeneity of macrophage origins, phenotypes, and functions in the OA joint and the effect of current symptomatic therapies on these cells. We then highlight the therapeutic potential of anticytokines/chemokines, nano- and microdrug delivery, and future strategies to modulate macrophage functions in OA.