Metabolic score for insulin resistance predicts major adverse cardiovascular event in premature coronary artery disease.

BACKGROUND: The Metabolic Score for Insulin Resistance (METS-IR) index serves as a simple surrogate marker for insulin resistance (IR) and is associated with the presence and severity of coronary artery disease (CAD). However, the prognostic significance of METS-IR in patients with premature CAD remains unclear. This study aims to investigate the prognostic value of METS-IR in premature CAD. METHODS: This retrospective study included 582 patients diagnosed with premature CAD between December 2012 and July 2019. The median follow-up duration was 63 months (interquartile range, 44-81 months). The primary endpoint was Major Adverse Cardiovascular Events (MACE), defined as a composite of all-cause death, non-fatal myocardial infarction (MI), repeat coronary artery revascularization, and non-fatal stroke. RESULTS: Patients with MACE had significantly higher METS-IR levels than those without MACE (44.88±8.11 vs. 41.68±6.87, p<0.001). Kaplan-Meier survival curves based on METS-IR tertiles demonstrated a statistically significant difference (log-rank test, p<0.001). In the fully adjusted model, the Hazard Ratio (95% CI) for MACE was 1.41 (1.16-1.72) per SD increase in METS-IR, and the P for trend based on METS-IR tertiles was 0.001 for MACE. Time-dependent Receiver Operator Characteristic (ROC) analysis of METS-IR yielded an Area Under the Curve (AUC) of 0.74 at 2 years, 0.69 at 4 years, and 0.63 at 6 years. CONCLUSIONS: METS-IR serves as a reliable prognostic predictor of MACE in patients with premature CAD. Therefore, METS-IR may be considered a novel, cost-effective, and dependable indicator for risk stratification and early intervention in premature CAD.

SorCS2 is involved in promoting periodontitis-induced depression-like behaviour in mice.

BACKGROUND: Emerging evidence supports the association between periodontitis and depression, although the mechanisms are unclear. This study investigated the role of SorCS2 in the pathogenesis of periodontitis-induced depression. MATERIALS AND METHODS: An experimental periodontitis model was established using SorCS2 knockout mice and their wild-type littermates, and depression-like behaviour was evaluated. The expression of proBDNF signalling, neuronal activity, and glutamate-associated signalling pathways were further measured by western blotting and immunofluorescence. In addition, neuroinflammatory status, astrocytic and microglial markers, and the expression of corticosterone-related factors were measured by immunofluorescence, western blotting, and enzyme-linked immunosorbent assays. RESULTS: SorCS2 deficiency alleviated periodontitis-induced depression-like behaviour in mice. Further results suggested that SorCS2 deficiency downregulated the expression of pro-BDNF and glutamate signalling and restored neuronal activities in mice with periodontitis. Neuroinflammation in the mouse hippocampus was triggered by experimental periodontitis but was not affected by SorCS2 deficiency. The levels of corticosterone and the expression of glucocorticoid receptors were also not altered. CONCLUSION: Our study, for the first time, reveals the critical role of SorCS2 in the pathogenesis of periodontitis-induced depression. The underlying mechanism involves proBDNF and glutamate signalling in the hippocampus, providing a novel therapeutic target for periodontitis-associated depression.

Ionic Liquid-Enhanced Assembly of Nanomaterials for Highly Stable Flexible Transparent Electrodes.

The controlled assembly of nanomaterials has demonstrated significant potential in advancing technological devices. However, achieving highly efficient and low-loss assembly technique for nanomaterials, enabling the creation of hierarchical structures with distinctive functionalities, remains a formidable challenge. Here, we present a method for nanomaterial assembly enhanced by ionic liquids, which enables the fabrication of highly stable, flexible, and transparent electrodes featuring an organized layered structure. The utilization of hydrophobic and nonvolatile ionic liquids facilitates the production of stable interfaces with water, effectively preventing the sedimentation of 1D/2D nanomaterials assembled at the interface. Furthermore, the interfacially assembled nanomaterial monolayer exhibits an alternate self-climbing behavior, enabling layer-by-layer transfer and the formation of a well-ordered MXene-wrapped silver nanowire network film. The resulting composite film not only demonstrates exceptional photoelectric performance with a sheet resistance of 9.4 Ω sq-1 and 93% transmittance, but also showcases remarkable environmental stability and mechanical flexibility. Particularly noteworthy is its application in transparent electromagnetic interference shielding materials and triboelectric nanogenerator devices. This research introduces an innovative approach to manufacture and tailor functional devices based on ordered nanomaterials.

Gastrointestinal infections and gastrointestinal haemorrhage are underestimated but serious adverse events in chimeric antigen receptor T-cell recipients: A real-world study.

Chimeric antigen receptor T-cell (CAR-T) therapy has achieved durable response in patients with hematological malignancies, however, therapy-associated multisystem toxicities are commonly observed. Here, we systematically analyzed CAR-T-related gastrointestinal adverse events (GAEs) using the U.S. Food and Drug Administration Adverse Event Reporting System (FAERS) between January 2017 and December 2021. Disproportionality analyses were performed using reporting odds ratios (ROR) and information component (IC). Among 105,087,611 reports in FAERS, 1518 CAR-T-related GAEs reports were identified. 23 GAEs (n = 281, 18.51%) were significantly overreported following CAR-T therapy compared with the full database, of which 11 GAEs (n = 156, 10.28%) were associated with gastrointestinal infections (GI), such as clostridium difficile colitis (n = 44 [2.90%], ROR = 5.55), enterovirus infection (n = 23 [1.52%], ROR = 20.02), and mucormycosis (n = 15 [0.99%], ROR = 3.09). Overall, the fatality rate of 11 GI-related AEs was 29.49%, especially mucormycosis causing substantial mortality with 60%. In addition, 4 of 23 overreported GAEs were related to haemorrhage and the mortality of gastrointestinal haemorrhage was 73.17%. Lastly, 29 death-related GAEs were identified. These findings could help clinicians early alert those rarely reported but lethal GAEs, thus reducing the risk of severe toxicities.

Comparison of seven surrogate insulin resistance indexes for prediction of incident coronary heart disease risk: a 10-year prospective cohort study.

Background: There were seven novel and easily accessed insulin resistance (IR) surrogates established, including the Chinese visceral adiposity index (CVAI), the visceral adiposity index (VAI), lipid accumulation product (LAP), triglyceride glucose (TyG) index, TyG-body mass index (TyG-BMI), TyG-waist circumference (TyG-WC) and TyG-waist to height ratio (TyG-WHtR). We aimed to explore the association between the seven IR surrogates and incident coronary heart disease (CHD), and to compare their predictive powers among Chinese population. Methods: This is a 10-year prospective cohort study conducted in China including 6393 participants without cardiovascular disease (CVD) at baseline. We developed Cox regression analyses to examine the association of IR surrogates with CHD (hazard ratio [HR], 95% confidence intervals [CI]). Moreover, the receiver operating characteristic (ROC) curve was performed to compare the predictive values of these indexes for incident CHD by the areas under the ROC curve (AUC). Results: During a median follow-up period of 10.25 years, 246 individuals newly developed CHD. Significant associations of the IR surrogates (excepted for VAI) with incident CHD were found in our study after fully adjustment, and the fifth quintile HRs (95% CIs) for incident CHD were respectively 2.055(1.216-3.473), 1.446(0.948-2.205), 1.753(1.099-2.795), 2.013(1.214-3.339), 3.169(1.926-5.214), 2.275(1.391-3.719) and 2.309(1.419-3.759) for CVAI, VAI, LAP, TyG, TyG-BMI, TyG-WC and TyG-WHtR, compared with quintile 1. Furthermore, CVAI showed maximum predictive capacity for CHD among these seven IR surrogates with the largest AUC: 0.632(0.597,0.667). Conclusion: The seven IR surrogates (excepted for VAI) were independently associated with higher prevalence of CHD, among which CVAI is the most powerful predictor for CHD incidence in Chinese populations.

Gsα Regulates Macrophage Foam Cell Formation During Atherosclerosis.

BACKGROUND: Many cardiovascular pathologies are induced by signaling through G-protein-coupled receptors via Gsα (G protein stimulatory α subunit) proteins. However, the specific cellular mechanisms that are driven by Gsα and contribute to the development of atherosclerosis remain unclear. METHODS: High-throughput screening involving data from single-cell and bulk sequencing were used to explore the expression of Gsα in atherosclerosis. The differentially expression and activity of Gsα were analyzed by immunofluorescence and cAMP measurements. Macrophage-specific Gsα knockout (Mac-GsαKO) mice were generated to study the effect on atherosclerosis. The role of Gsα was determined by transplanting bone marrow and performing assays for foam cell formation, Dil-ox-LDL (oxidized low-density lipoprotein) uptake, chromatin immunoprecipitation, and luciferase reporter assays. RESULTS: ScRNA-seq showed elevated Gnas in atherosclerotic mouse aorta's cholesterol metabolism macrophage cluster, while bulk sequencing confirmed increased GNAS expression in human plaque macrophage content. A significant upregulation of Gsα and active Gsα occurred in macrophages from human and mouse plaques. Ox-LDL could translocate Gsα from macrophage lipid rafts in short-term and promote Gnas transcription through ERK1/2 activation and C/EBPß phosphorylation via oxidative stress in long-term. Atherosclerotic lesions from Mac-GsαKO mice displayed decreased lipid deposition compared with those from control mice. Additionally, Gsα deficiency alleviated lipid uptake and foam cell formation. Mechanistically, Gsα increased the levels of cAMP and transcriptional activity of the cAMP response element binding protein, which resulted in increased expression of CD36 and SR-A1. In the translational experiments, inhibiting Gsα activation with suramin or cpGN13 reduced lipid uptake, foam cell formation, and the progression of atherosclerotic plaques in mice in vivo. CONCLUSIONS: Gsα activation is enhanced during atherosclerotic progression and increases lipid uptake and foam cell formation. The genetic or chemical inactivation of Gsα inhibit the development of atherosclerosis in mice, suggesting that drugs targeting Gsα may be useful in the treatment of atherosclerosis.

Paraspeckle protein NONO attenuates vascular calcification by inhibiting bone morphogenetic protein 2 transcription.

Vascular calcification is a pathological process commonly associated with atherosclerosis, chronic kidney disease, and diabetes. Paraspeckle protein NONO is a multifunctional RNA/DNA binding protein involved in many nuclear biological processes but its role in vascular calcification remains unclear. Here, we observed that NONO expression was decreased in calcified arteries of mice and patients with CKD. We generated smooth muscle-specific NONO-knockout mice and established three different mouse models of vascular calcification by means of 5/6 nephrectomy, adenine diet to induce chronic kidney failure, or vitamin D injection. The knockout mice were more susceptible to the development of vascular calcification relative to control mice, as verified by an increased calcification severity and calcium deposition. Likewise, aortic rings from knockout mice showed more significant vascular calcification than those from control mice ex vivo. In vitro, NONO deficiency aggravated high phosphate-induced vascular smooth muscle cell osteogenic differentiation and apoptosis, whereas NONO overexpression had a protective effect. Mechanistically, we demonstrated that the regulation of vascular calcification by NONO was mediated by bone morphogenetic protein 2 (BMP2). NONO directly bound to the BMP2 promoter using its C-terminal region, exerting an inhibitory effect on the transcription of BMP2. Thus, our study reveals that NONO is a novel negative regulator of vascular calcification, which inhibits osteogenic differentiation of vascular smooth muscle cell and vascular calcification via negatively regulating BMP2 transcription. Hence, NONO may provide a promising target for the prevention and treatment of vascular calcification.

Electrospun Biomimetic Periosteum Capable of Controlled Release of Multiple Agents for Programmed Promoting Bone Regeneration.

The effective repair of large bone defects remains a major challenge due to its limited self-healing capacity. Inspired by the structure and function of the natural periosteum, an electrospun biomimetic periosteum is constructed to programmatically promote bone regeneration using natural bone healing mechanisms. The biomimetic periosteum is composed of a bilayer with an asymmetric structure in which an aligned electrospun poly(ε-caprolactone)/gelatin/deferoxamine (PCL/GEL/DFO) layer mimics the outer fibrous layer of the periosteum, while a random coaxial electrospun PCL/GEL/aspirin (ASP) shell and PCL/silicon nanoparticles (SiNPs) core layer mimics the inner cambial layer. The bilayer controls the release of ASP, DFO, and SiNPs to precisely regulate the inflammatory, angiogenic, and osteogenic phases of bone repair. The random coaxial inner layer can effectively antioxidize, promoting cell recruitment, proliferation, differentiation, and mineralization, while the aligned outer layer can promote angiogenesis and prevent fibroblast infiltration. In particular, different stages of bone repair are modulated in a rat skull defect model to achieve faster and better bone regeneration. The proposed biomimetic periosteum is expected to be a promising candidate for bone defect healing.

Manganese induces neuronal apoptosis by activating mTOR signaling pathway in vitro and in vivo.

Manganese (Mn) is a well-known environmental pollutant and occupational toxicant that causes neurotoxicity, which present as neurodegenerative-like symptoms. However, the mechanism of Mn-induced neuronal injury remains unclear. In this research, we explored the mechanism of Mn-induced neurotoxicity, focusing on the mTOR signaling pathway. A plasmid expressing a short hairpin RNA (shRNA) targeting mTOR (shRNA-mTOR) was transfected into N27 cells in vitro, and rapamycin was used as an mTOR inhibitor in vivo to block the mTOR signaling pathway. Cells were treated with different concentrations of manganese (II) chloride (MnCl2). We found that Mn induced cell injury and apoptosis and markedly upregulated the expression of mTOR pathway-related proteins. The phosphorylation of 4E-BP1, S6K1, Akt and SGK1 was markedly decreased after blocking mTOR, and cell apoptosis was also reduced. Furthermore, the mTOR-specific inhibitor rapamycin restored learning and memory abilities in vivo. This research highlights that inhibiting mTOR might be useful for preventing Mn-induced neurodegenerative-like disorders.

Association between the triglyceride-glucose index and impaired cardiovascular fitness in non-diabetic young population.

BACKGROUND: The triglyceride-glucose (TyG) index has been linked to the onset, progression, and prognosis of cardiovascular disease (CVD) in middle-aged and elderly individuals. Nevertheless, the relationship between the TyG index and impaired cardiovascular fitness (CVF) remains unexplored in non-diabetic young population. METHODS: We used data from the National Health and Nutrition Examination Survey (NHANES) study (1999-2004) to conduct a cross-sectional study of 3364 participants who completed an examination of CVF. Impaired CVF was defined as low and moderate CVF levels determined by estimated maximal oxygen consumption (Vo2max), based on sex- and age-specific criteria. The TyG index was calculated by [Formula: see text]. RESULTS: The age (median with interquartile range) of the study population was 28 (19-37) years, and the TyG index (median ± standard deviation) was 8.36 ± 0.52. A significant association between the TyG index and impaired CVF was found in multivariable logistical regression analysis (per 1-unit increase in the TyG index: OR, 1.46; 95% Cl 1.13-1.90). A dose‒response relationship between the TyG index and impaired CVF was presented by restricted cubic splines (RCS). A significant interaction (p = 0.027) between sex and the TyG index for impaired CVF was found in the population aged < 20 years. CONCLUSIONS: In non-diabetic young population, individuals with higher TyG index values are at an increased likelihood of encountering impaired CVF. Furthermore, sex may exert an impact on CVF, as males tend to be more susceptible to impaired CVF under comparable TyG index conditions.

NIR-Light-Triggered Mild-Temperature Hyperthermia to Overcome the Cascade Cisplatin Resistance for Improved Resistant Tumor Therapy.

Currently, cisplatin resistance has been recognized as a multistep cascade process for its clinical chemotherapy failure. Hitherto, it remains challenging to develop a feasible and promising strategy to overcome the cascade drug resistance (CDR) issue for achieving fundamentally improved chemotherapeutic efficacy. Herein, a novel self-assembled nanoagent is proposed, which is constructed by Pt(IV) prodrug, cyanine dye (cypate), and gadolinium ion (Gd3+), for systematically conquering the cisplatin resistance by employing near-infrared (NIR) light activated mild-temperature hyperthermia in tumor targets. The proposed nanoagents exhibit high photostability, GSH/H+-responsive dissociation, preferable photothermal conversion, and enhanced cellular uptake performance. In particular, upon 785-nm NIR light irradiation, the generated mild temperature of ≈ 43 °C overtly improves the cell membrane permeability and drug uptake, accelerates the disruption of intracellular redox balance, and apparently enhances the formation of Pt-DNA adducts, thereby effectively overcoming the CDR issue and achieves highly improved therapeutic efficacy for cisplatin-resistant tumor ablation.

Prevalence, characteristics and significant predictors for cardiovascular disease of patients with preserved ratio impaired spirometry: A 10-year prospective cohort study in China.

BACKGROUND AND OBJECTIVE: Patients with preserved ratio impaired spirometry (PRIsm) have higher incidence rate of cardiovascular disease (CVD). However, few studies focused on PRIsm in China. We determined the prevalence and characteristics of patients with PRIsm in Chinese population. We also aimed to investigate the significant predictive factors of CVD in PRIsm patients. METHODS: In total, 6994 subjects aged from 35 to 70 years old and free of CVD at baseline were categorized into normal (n = 3895), PRIsm (the ratio of forced expired volume in the first second (FEV1) to forced vital capacity (FVC) ≥0.7 and FEV1 <80 % predicted; n = 1997) and obstructive spirometry (FEV1:FVC<0.7; n = 1102). Cox proportional hazards multivariable regression was performed to investigate how baseline characteristics impact CVD incidence. RESULTS: In participants with PRIsm, men had a 0.68-fold higher risk of CVD incidence than women (HR, 1.68; 95%CI, 1.09-2.59; p = 0.020). Our study showed that the rate of CVD incidence increased by 6.0 % with every year's increase in age (HR, 1.06; 95%CI, 1.04-1.09; p < 0.001). A 0.1 increase in FEV1/FVC was significantly associated with a 23.0 % decrease in CVD incidence (HR, 0.77; 95%CI, 0.61-0.97; p = 0.028). Family history of CVD greatly increased the risk of cardiovascular disease incidence (HR, 1.83; 95%CI, 1.18-2.83; p = 0.007). Higher BMI was also a significant risk factor of CVD incidence (HR, 1.06; 95%CI, 1.01-1.10; p = 0.013). CONCLUSION: The prevalence of PRIsm in China was high. PRIsm subjects should be monitored carefully, especially for the older, male, those with higher BMI, lower FEV1/FVC and family history of CVD.

Alterations in mitochondrial structure and function in response to environmental temperature changes in Apostichopus japonicus.

Global temperatures have risen as a result of climate change, and the resulting warmer seawater will exert physiological stresses on many aquatic animals, including Apostichopus japonicus. It has been suggested that the sensitivity of aquatic poikilothermal animals to climate change is closely related to mitochondrial function. Therefore, understanding the interaction between elevated temperature and mitochondrial functioning is key to characterizing organisms' responses to heat stress. However, little is known about the mitochondrial response to heat stress in A. japonicus. In this work, we investigated the morphological and functional changes of A. japonicus mitochondria under three representative temperatures, control temperature (18 °C), aestivation temperature (25 °C) and heat stress temperature (32 °C) temperatures using transmission electron microscopy (TEM) observation of mitochondrial morphology combined with proteomics and metabolomics techniques. The results showed that the mitochondrial morphology of A. japonicus was altered, with decreases in the number of mitochondrial cristae at 25 °C and mitochondrial lysis, fracture, and vacuolization at 32 °C. Proteomic and metabolomic analyses revealed 103 differentially expressed proteins and 161 differential metabolites at 25 °C. At 32 °C, the levels of 214 proteins and 172 metabolites were significantly altered. These proteins and metabolites were involved in the tricarboxylic acid (TCA) cycle, substance transport, membrane potential homeostasis, anti-stress processes, mitochondrial autophagy, and apoptosis. Furthermore, a hypothetical network of proteins and metabolites in A. japonicus mitochondria in response to temperature changes was constructed based on proteomic and metabolomic data. These results suggest that the dynamic regulation of mitochondrial energy metabolism, resistance to oxidative stress, autophagy, apoptosis, and mitochondrial morphology in A. japonicus may play important roles in the response to elevated temperatures. In summary, this study describes the response of A. japonicus mitochondria to temperature changes from the perspectives of morphology, proteins, and metabolites, which provided a better understanding the mechanisms of mitochondrial regulation under environment stress in marine echinoderms.

Long-term outcomes with HLX01 (HanliKang®), a rituximab biosimilar, in previously untreated patients with diffuse large B-cell lymphoma: 5-year follow-up results of the phase 3 HLX01-NHL03 study.

HLX01 (HanliKang®) is a rituximab biosimilar that showed bioequivalence to reference rituximab in untreated CD20-positive diffuse large B-cell lymphoma (DLBCL) in the phase 3 HLX01-NHL03 study. Here, we report the 5-year follow-up results from the open-label extension part. Patients were randomised to either rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) or HLX01 plus CHOP (H-CHOP) every 21 days for up to six cycles. The primary efficacy endpoint was overall survival (OS), and secondary efficacy endpoint was progression-free survival (PFS). Of the 407 patients enrolled in HLX01-NHL03, 316 patients (H-CHOP = 157; R-CHOP = 159) were included in the 5-year follow-up for a median duration of 65.1 (range, 2.2-76.5) months. 96.5% of the patients had an International Prognostic Index (IPI) of 1 or 2, and 17.7% had bone marrow involvement. The 5-year OS rates were 81.0% (95% CI: 74.9-87.5%) and 75.4% (95% CI: 68.9-82.6%)( HR: 0.75, 95% CI 0.47-1.20; p = 0.23) while 5-year PFS rates were 77.7% (95% CI: 71.4-84.6%) and 73.0% (95% CI: 66.3-80.3%) (HR: 0.84, 95% CI 0.54-1.30; p = 0.43) in the H-CHOP and R-CHOP groups, respectively. Treatment outcomes did not differ between groups regardless of IPI score and were consistent with the primary analysis. H-CHOP and R-CHOP provided no significant difference in 5-year OS or PFS in previously untreated patients with low or low-intermediate risk DLBCL.

Rubropunctatin-silver composite nanoliposomes for eradicating Helicobacter pylori in vitro and in vivo.

Helicobacter pylori (H. pylori) is a major factor in peptic ulcer disease and gastric cancer, and its infection rate is rising globally. The efficacy of traditional antibiotic treatment is less effective, mainly due to bacterial biofilms and the formation of antibiotic resistance. In addition, H. pylori colonizes the gastrointestinal epithelium covered by mucus layers, the drug must penetrate the double barrier of mucus layer and biofilm to reach the infection site and kill H. pylori. The ethanol injection method was used to synthesize nanoliposomes (EPI/R-AgNPs@RHL/PC) with a mixed lipid layer containing rhamnolipids (RHL) and phosphatidylcholine (PC) as a carrier, loaded with the urease inhibitor epiberberine (EPI) and the antimicrobial agent rubropunctatin silver nanoparticles (R-AgNPs). EPI/R-AgNPs@RHL/PC had the appropriate size, negative charge, and acid sensitivity to penetrate mucin-rich mucus layers and achieve acid-responsive drug release. In vitro experiments demonstrated that EPI/R-AgNPs@RHL/PC exhibited good antibacterial activity, effectively inhibited urease activity, removed the mature H. pylori biofilm, and inhibited biofilm regeneration. In vivo antibacterial tests showed that EPI/R-AgNPs@RHL/PC exhibited excellent activity in eradicating H. pylori and protecting the mucosa compared to the traditional clinical triple therapy, providing a new idea for the treatment of H. pylori infection.

Chitosan nonwoven fabric composited calcium alginate and adenosine diphosphate as a hemostatic bandage for acute bleeding wounds.

Acute bleeding following accidental injury is a leading cause of mortality. However, conventional hemostatic bandages impede wound healing by inducing excessive blood loss, dehydration, and adherence to granulation tissue. Strategies such as incorporating active hemostatic agents and implementing chemical modifications can augment the properties of these bandages. Nevertheless, the presence of remote thrombosis and initiators may pose risks to human health. Here, a hemostatic bandage was developed by physically combined chitosan nonwoven fabric, calcium alginate sponge, and adenosine diphosphate. The presented hemostatic bandage not only exhibits active and passive mechanisms for promoting clotting but also demonstrates excellent mechanical properties, breathability, ease of removal without causing damage to the wound bed or surrounding tissues, as well as maintaining an optimal moist environment conducive to wound healing. In vitro evaluation results indicated that the hemostatic bandage possesses favorable cytocompatibility with low levels of hemolysis. Furthermore, it effectively aggregates various blood cells while activating platelets synergistically to promote both extrinsic and intrinsic coagulation pathways. In an in vivo rat model study involving liver laceration and femoral artery injury scenarios, our developed hemostatic bandage demonstrated rapid clot formation capabilities along with reduced blood loss compared to commercially available fabrics.

Biomimetic injectable and bilayered hydrogel scaffold based on collagen and chondroitin sulfate for the repair of osteochondral defects.

The simultaneous regeneration of articular cartilage and subchondral bone is a major challenge. Bioinspired scaffolds with distinct regions resembling stratified anatomical architecture provide a potential strategy for osteochondral defect repair. Here, we report the development of an injectable and bilayered hydrogel scaffold with a strong interface binding force. In this bilayer hydrogel, composed of carbonyl hydrazide grafted collagen (COL-CDH) and oxidized chondroitin sulfate (OCS), which are derivatives of osteochondral tissue components, in combination with poly (ethylene glycol) diacrylate (PEGDA), functions as a cartilage layer; while zinc-doped hydroxyapatite acts as a subchondral bone layer that is based on the cartilage layer. The strong interface between the two layers involves dynamic amide bonds formed between COL-CDH and OCS, and permanent CC bonds formed by PEGDA radical reactions. This bilayer hydrogel can be used to inoculate adipose mesenchymal stem cells which can then differentiate into chondrocytes and osteoblasts, secreting glycosaminoglycan, and promoting calcium deposition. This accelerates the regeneration of cartilage and subchondral bone. Micro-CT and tissue staining revealed an increase in the amount of bone present in new subchondral bone, and new tissues with a structure similar to normal cartilage. This study therefore demonstrates that injectable bilayer hydrogels are a promising scaffold for repairing osteochondral defects.