Green synthesis-inspired antibacterial, antioxidant and adhesive hydrogels with ultra-fast gelation and hemostasis for promoting infected skin wound healing.

Bacterial infections are a serious threat to wound healing and skin regeneration. In recent years, photothermal therapy (PTT) has become one of the most promising tools in the treatment of infectious diseases. However, wound dressings with photo-responsive properties are currently still limited by the difficulties of biosafety and thermal stability brought by the introduction of photosensitizers or photothermal agents. Therefore, how to improve the therapeutic efficiency and biosafety from material design is still a major challenge at present. In this study, the carboxymethyl chitosan (CMCS) and protocatechuic aldehyde (PA) hydrogels based on horseradish peroxidase (HRP) and hydrogen peroxide (H2O2) enzymatic catalysis was developed. Therein, HRP and H2O2 catalyzed cross-linking while polymerizing PA, which not only endowed the hydrogels with photothermal responsiveness but also with good biosafety through this enzyme-catalyzed green approach. Meanwhile, the hydrogels possessed highly efficient bacteriostatic ability with the assistance of near infrared (NIR). Moreover, the ultra-rapid gelation, strong tissue adhesion, high swelling ability, good antioxidant property and hemostatic property of the CMCS-PA hydrogels based on HRP/H2O2 enzymatic catalysis were suitable for the treatment of skin wounds. Meanwhile, NIR-assistant CMCS-PA hydrogels based on HRP/H2O2 enzymatic catalysis reduced inflammation, decreased bacterial infection, and promoted collagen deposition and angiogenesis, which showed remarkable therapeutic effects in a skin wound infection model. All results indicate that this green approach to introduce photothermal property by HRP-catalyzed PA polymerization endows the hydrogels with efficient photothermal conversion efficiency, suggesting that they are promising to provide new options for replacing photothermal agents and photosensitizers. STATEMENT OF SIGNIFICANCE: In recent years, wound dressings with photo-responsive properties are currently still limited by the difficulties of biosafety and thermal stability brought by the introduction of agent photosensitizers or photothermal agents. In this study, the carboxymethyl chitosan and protocatechuic aldehyde hydrogels based on horseradish peroxidase and hydrogen peroxide enzymatic catalysis was developed. The photothermal properties of hydrogels were transformed from absent to present just by horseradish peroxidase-catalyzed protocatechuic aldehyde polymerization in a green approach. Meanwhile, the hydrogels possessed highly efficient bacteriostatic ability with the assistance of near infrared. The green approach of introducing photothermal properties from material design solves the biosafety challenge. Therefore, this study is expected to provide new options for alternative photothermal agents and photosensitizers.

Natural blackcurrant extract contained gelatin hydrogel with photothermal and antioxidant properties for infected burn wound healing.

Burns represent a prevalent global health concern and are particularly susceptible to bacterial infections. Severe infections may lead to serious complications, posing a life-threatening risk. Near-infrared (NIR)-assisted photothermal antibacterial combined with antioxidant hydrogel has shown significant potential in the healing of infected wounds. However, existing photothermal agents are typically metal-based, complicated to synthesize, or pose biosafety hazards. In this study, we utilized plant-derived blackcurrant extract (B) as a natural source for both photothermal and antioxidant properties. By incorporating B into a G-O hydrogel crosslinked through Schiff base reaction between gelatin (G) and oxidized pullulan (O), the resulting G-O-B hydrogel exhibited good injectability and biocompatibility along with robust photothermal and antioxidant activities. Upon NIR irradiation, the controlled temperature (around 45-50 °C) generated by the G-O-B hydrogel resulted in rapid (10 min) and efficient killing of Staphylococcus aureus (99 %), Escherichia coli (98 %), and Pseudomonas aeruginosa (82 %). Furthermore, the G-O-B0.5 hydrogel containing 0.5 % blackcurrant extract promoted collagen deposition, angiogenesis, and accelerated burn wound closure conclusively, demonstrating that this well-designed and extract-contained hydrogel dressing holds immense potential for enhancing the healing process of bacterial-infected burn wounds.

Low power consumption grating magneto-optical trap based on planar elements.

The grating-based magneto-optical trap (GMOT) is a promising approach for miniaturizing cold-atom systems. However, the power consumption of a GMOT system dominates its feasibility in practical applications. In this study, we demonstrated a GMOT system based on planar elements that can operate with low power consumption. A high-diffraction-efficiency grating chip was used to cool atoms with a single incident beam. A planar coil chip was designed and fabricated with a low power consumption nested architecture. The grating and coil chips were adapted to a passive pump vacuum chamber, and up to 106 87Rb atoms were trapped. These elements effectively reduce the power consumption of the GMOT and have great potential for applications in practical cold-atom-based devices.

Cowberry extract loaded chitosan hydrogel with photothermal and antioxidant properties promotes infected wound healing.

Bacterial infection and oxidative stress impede clinical wound healing. Herein, the plant-derived cowberry extract (CE) was first explored as a natural photothermal agent and antioxidant to deal with bacterial infection and oxidative stress. After loading in the carboxymethyl chitosan (CMCs)/oxidized dextran (Odex) hydrogel, the photothermal effect of CE was highly enhanced by CMCs. The controlled temperature induced by CE-containing hydrogel under NIR laser irradiation could rapidly (10 min) and effectively kill Staphylococcus aureus (S. aureus, 99.3 %) and Escherichia coli (E. coli, 94.6 %). Besides, this hydrogel exhibited a fast gelation and hemostasis abilities, high stability, adhesion and ROS scavenging capabilities, as well as good injectability and biocompatibility. Above superior properties make this hydrogel to accelerate the wound healing in S. aureus-infected mice, and it is expected to be a potential clinical wound dressing.

Genetically predicted telomere length and the risk of 11 hematological diseases: a Mendelian randomization study.

OBJECTIVE: Previous studies have demonstrated that various hematologic diseases (HDs) induce alterations in telomere length (TL). The aim of this study is to investigate whether genetically predicted changes in TL have an impact on the risk of developing HDs. METHODS: GWAS data for TL and 11 HDs were extracted from the database. The R software package "TwoSampleMR" was employed to conduct a two-sample Mendelian randomization (MR) analysis, in order to estimate the influence of TL changes on the risk of developing the 11 HDs. RESULTS: We examined the effect of TL changes on the risk of developing the 11 HDs. The IVW results revealed a significant causal association between genetically predicted longer TL and the risk of developing acute lymphocytic leukemia (ALL), acute myeloid leukemia (AML), chronic lymphocytic leukemia (CLL), mantle cell lymphoma (MANTLE), and hodgkin lymphoma (HODGKIN). However, there was no significant causal relationship observed between TL changes and the risk of developing chronic myeloid leukemia (CML), diffuse large b-cell lymphoma (DLBCL), marginal zone b-cell lymphoma (MARGINAL), follicular lymphoma (FOLLICULAR), monocytic leukemia (MONOCYTIC), and mature T/NK-cell lymphomas (TNK). CONCLUSIONS: The MR analysis revealed a positive association between genetically predicted longer TL and an increased risk of developing ALL, AML, CLL, MANTLE, and HODGKIN. This study further supports the notion that cells with longer TL have greater proliferative and mutational potential, leading to an increased risk of certain HDs.

Mild hyperthermia-assisted chitosan hydrogel with photothermal antibacterial property and CAT-like activity for infected wound healing.

Infected wounds pose a serious threat to public health and pose a significant challenge and financial burden worldwide. The treatment of infected wounds is now an urgent problem to be solved. Herein, mild hyperthermia-assisted hydrogels composed of carboxymethyl chitosan (CMCs), oxidized dextran (Odex), epigallocatechin gallate (EGCG) and PtNPs@PVP (CAT-like nanoenzymes) were proposed for the repair of infected wounds. The incorporation of PtNPs@PVP nanoenzymes give the hydrogels excellent photothermal property and CAT-like activity. When the temperature is maintained at 42-45 °C under 808 nm near infrared (NIR) exposure, the CMCs/Odex/EGCG/Nanoenzymes (COEN2) hydrogel demonstrated highly enhanced antibacterial ability (95.9 % in vivo), hydrogen peroxide (H2O2) scavenging ratio (85.1 % in vitro) and oxygen supply (20.7 mg/L in vitro). Furthermore, this mild-heat stimulation also promoted angiogenesis in the damaged skin area. Overall, this multifunctional hydrogel with antibacterial, antioxidant, oxygen supply, hemostasis, and angiogenesis capabilities has shown great promise in the repair of infected wounds. This study establishes the paradigm of enhanced infected wound healing by mild hyperthermia-assisted H2O2 scavenging, oxygen supplemental, and photothermal antibacterial hydrogels.

ROS/pH dual responsive PRP-loaded multifunctional chitosan hydrogels with controlled release of growth factors for skin wound healing.

Platelet-rich plasma (PRP) contains a variety of growth factors (GFs) and has been used in the treatment of a variety of diseases, including skin lesions. In particular, PRP with low immunogenicity will be more widely used. However, the explosive release of GFs limits its further application. In order to achieve controlled release of GFs, a multifunctional and reactive oxygen species (ROS)/pH dual responsive hydrogel was developed to load PRP derived from human cord blood for the treatment of skin wound healing. Based on the hydrogen bond and Schiff base interaction, carboxymethyl chitosan (CMCS), oxidized dextran (Odex) and oligomeric procyanidins (OPC) were crosslinked to form CMCS/Odex/OPC/PRP hydrogel with good injectability, self-healing, adhesion, ROS scavenging, antibacterial activity, controlled and sustained release of GFs. In vitro cell experiments suggested that this hydrogel possessed excellent biocompatibility and could promote the proliferation and migration of L929. In vivo healing of full-layer skin wounds further indicated that the prepared hydrogel could regulate inflammation and promote epithelialization, collagen deposition, and angiogenesis. In summary, this present study demonstrates that CMCS/Odex/OPC/PRP hydrogel may serve as a promising multifunctional dressing for skin wound healing.

A multifunctional hydrogel dressing with high tensile and adhesive strength for infected skin wound healing in joint regions.

Most hydrogel dressings are designed for skin wounds in flat areas, and few are focused on the joint skin regions which undergo frequent movement. The mismatch of mechanical properties and poor fit between a hydrogel dressing and a wound in joint skin results in hydrogel shedding, bacterial infection and delayed healing. Therefore, it is of great significance to design and prepare a multifunctional hydrogel with high tensile and tissue-adhesive strength as well as other therapeutic effects for the treatment of joint skin wounds. In this work, a multifunctional hydrogel was reasonably prepared by simply mixing polyvinyl alcohol (PVA), borax, tannic acid (TA) and iron(III) chloride in certain proportions, which was further used to treat the skin wounds at the joint of the hind limb. Acting as the physical crosslinkers, borax and TA dynamically bond with PVA and provide the resulting hydrogel with strong tensile, fast shape-adaptive and self-healing properties. The photothermal bacteriostatic activity of the hydrogel is attributed to the formation of a metallic polyphenol network (MPN) between ferric ions and TA. In addition, the hydrogel exhibits high levels of adhesion, hemostatic performance, antioxidant abilities, and biocompatibility, and shows great potential to promote joint skin wound healing.

PMN-incorporated multifunctional chitosan hydrogel for postoperative synergistic photothermal melanoma therapy and skin regeneration.

Melanoma excision surgery is usually accompanied by neoplasm residual, tissue defect, and bacterial infection, resulting in high tumor recurrence and chronic wound. Nanocomposite hydrogels can satisfy the twin requirements of avoiding tumor recurrence and skin wound healing following skin melanoma surgery due to their photothermal anti-tumor and anti-bacterial activities. In this study, carboxymethyl chitosan, oxidized fucoidan and polyphenol-metal nanoparticle (PMN) of tannic acid capped gold nanoparticles were used to fabricate multifunctional nanocomposite hydrogels through Schiff base reaction. The prepared hydrogel demonstrated outstanding photothermal effect, and the controlled high temperature will rapidly kill melanoma cells as well as bacteria within 10 min. Good injectability, self-healing and adhesion combined with high reactive oxygen species (ROS) scavenging capacity, hemostasis and biocompatibility made this hydrogel platform perfect for the postoperative treatment of melanoma and promoting wound healing. With the assistance of NIR irradiance, hydrogel can inhibit tumor tissue proliferation and promote tumor cell apoptosis, thereby helping to prevent melanoma recurrence after surgical removal of tumors. Simultaneously, the irradiance heat and polyphenol component kill bacteria on the wound surface, eliminate ROS, inhibit inflammatory responses, and promote angiogenesis, collagen deposition, and skin regeneration, all of which help to speed up wound healing.

Correction: Ren et al. Injectable and Antioxidative HT/QGA Hydrogel for Potential Application in Wound Healing. Gels 2021, 7, 204.

In the original publication [...].

Application of cell membrane-functionalized biomimetic nanoparticles in the treatment of glioma.

Glioma is one of the most common malignant tumors with characteristics of strong invasion and high postoperative recurrence rate, which seriously threatens human health. Nanoparticles as an emerging drug delivery system have promoted the development of glioma therapy. However, blocking of nanoparticles by the blood-brain barrier is still serious problem for the use of nanoparticles in glioma therapy. In this context, traditional nanoparticles are dressed with natural cell membranes to prepare biomimetic nanoparticles. Biomimetic nanoparticles show longer blood circulation time, excellent homologous targeting and outstanding immune escape capacity, which significantly improve the accumulation of nanoparticles at the tumor site. The therapeutic effect for glioma has been raised to an advanced level. This review focuses on the preparations and applications of cell membrane-functionalized biomimetic nanoparticles, as while as the advantages and problems of biomimetic nanoparticles in the treatment of glioma. In particular, the approach of using biomimetic nanoparticles to cross the blood-brain barrier is analyzed, in the hope of providing new ideas for further developments in crossing the blood-brain barrier and in glioma therapy.

Ultra-stretchable, tissue-adhesive, shape-adaptive, self-healing, on-demand removable hydrogel dressings with multiple functions for infected wound healing in regions of high mobility.

Bacterial infection in the most mobile area usually leads to delayed healing and functional restriction, which has been a long-term challenge in clinic. Developing hydrogel-based dressings with mechanical flexibly, high adhesive and anti-bacterial properties, will contribute to the healing and therapeutic effects especially for this typical skin wound. In this work, composite hydrogel named PBOF through multi-reversible bonds between polyvinyl alcohol, borax, oligomeric procyanidin and ferric ion demonstrated a 100 times ultra-stretch ability, 24 kPa of highly tissue-adhesive, rapid shape-adaptability within 2 min and self-healing feature within 40 s, was designed as the multifunctional wound dressing for the Staphylococcus aureus-infected skin wound in the mice nape model. Besides, this hydrogel dressing could be easily removed on-demand within 10 min by water. The rapid disassembly of this hydrogel is related to the formation of hydrogen bonds between polyvinyl alcohol and water. Moreover, the multifunctional properties of this hydrogel include strong anti-oxidative, anti-bacteria and hemostasis derived from oligomeric procyanidin and photothermal effect of ferric ion/polyphenol chelate. The killing ratio of the hydrogel on Staphylococcus aureus in infected skin wound reached 90.6% when exposed to 808 nm irradiation for 10 min. Simultaneously, reduced oxidative stress, suppressed inflammation, and promoted angiogenesis all together accelerated wound healing. Therefore, this well-designed multifunctional PBOF hydrogel holds great promise as skin wound dressing especially in the high mobile regions of the body. STATEMENT OF SIGNIFICANCE: An ultra-stretchable, highly tissue-adhesive, and rapidly shape-adaptive, self-healing and on-demand removable hydrogel based on multi-reversible bonds among polyvinyl alcohol, borax, oligomeric procyanidin and ferric ion is designed as dressing material for infected wound healing in the movable nape. The rapid on-demand removal of the hydrogel relates to the formation of hydrogen bonds between polyvinyl alcohol and water. This hydrogel dressing shows strong antioxidant capacity, rapid hemostasis and photothermal antibacterial ability. This is derived from oligomeric procyanidin and thephotothermal effect of ferric ion/polyphenol chelate, which eliminates bacterial infection, reduces oxidative stress, regulates inflammation, promotes angiogenesis, and finally accelerates the infected wound healing in movable part.

Nanocomposite multifunctional hyaluronic acid hydrogel with photothermal antibacterial and antioxidant properties for infected wound healing.

Bacterial infection and subsequent reactive oxygen species (ROS) damage are major factors that delay wound healing in infected skin. Recently, photothermal therapy (PTT), as a new antibacterial method, has shown great advantages in the treatment of infected skin wound. Antibacterial and antioxidant hydrogels can reduce bacterial colonization and infection, scavenge ROS, relieve inflammation, and accelerate wound healing. In this study, an enzyme-crosslinked hyaluronic acid-tyramine (HT) hydrogel loaded with antioxidant and photothermal silver nanoparticles (AgNPs), named HTA, was developed as functional wound dressing to promote the infected skin wound healing. Natural antioxidant tannic acids (TA) were used as both reducing and stabilizing agents to facilely synthesize the silver nanoparticles capped with TA (AgNPs@TA). The incorporation of AgNPs@TA significantly enhanced the antioxidant, antibacterial, photothermal antibacterial, adhesive, and hemostatic abilities of the resulted HTA hydrogel. Besides, HTA hydrogel has rapid gelation, well injection and biocompatibility. In vivo results on the Staphylococcus aureus and Escherichia coli co-infected mouse skin wound model showed that HTA0.4 (containing 0.4 mg/mL AgNPs@TA) hydrogel combined with near infrared ray radiation highly alleviated inflammation, promoted angiogenesis, and accelerated the healing process. Therefore, this nanocomposite hydrogel wound dressing with antibacterial and antioxidant capabilities has great application potential in the treatment of infected skin wounds.

Multifunctional hydrogel with reactive oxygen species scavenging and photothermal antibacterial activity accelerates infected diabetic wound healing.

Management of diabetic wound has long been a clinical challenge due to pathological microenvironment of excessive inflammation, persistent hyperglycemia, and biofilm infection caused by overdue reactive oxygen species (ROS) production and defective blood vessels. Herein, a multifunctional hydrogel with ROS scavenging and photothermal antibacterial activity based on oxidized dextran (Odex), gallic acid-grafted gelatin (GAG) and Ferric ion, named OGF, was developed for treatment of infected wound in a diabetic mouse. This hydrogel was double-crosslinked by the dynamically Schiff-base bonds formed between aldehyde groups in Odex and amino groups in GAG and the metal coordination bonds formed between Ferric ion and polyphenol groups or carboxyl groups in GAG, which endowed the resulted OGF hydrogel with well injectable, self-healing and adhesive properties. Due to the high-efficiency photothermal effect of Ferric ion/polyphenol chelate, this hydrogel killed Staphylococcus aureus and Escherichia coli rapidly and completely within 3.5 min under near-infrared light radiation. Furthermore, this composed hydrogel presented good antioxidation, hemostasis and biocompatibility. It also remarkably accelerated the complete re­epithelialization of Staphylococcus aureus­infected wound in diabetic mice within 18 days by eliminating infection, mitigating oxidative stress and inflammation, and facilitating angiogenesis. Therefore, the proposed multifunctional hydrogel exerts a great potential for translation in the clinical management of diabetic wounds. STATEMENT OF SIGNIFICANCE: High reactive oxygen species (ROS) levels and vascular defects in diabetic wounds can lead to excessive inflammation, persistent hyperglycemia, biofilm infection and other pathological microenvironments, which can further develop to the chronic wounds. In this study, we designed a multifunctional hydrogel with ROS-scavenging ability and photothermal antibacterial activity for the treatment of infected diabetic wound. As expected, this multifunctional hydrogel dressing highly accelerated the complete re­epithelialization of Staphylococcus aureus­infected wound in diabetic mouse by eliminating infection, mitigating oxidative stress and inflammation, as well as facilitating angiogenesis. This work provides a promising therapeutic strategy for infected diabetic wound by inhibition of oxidative stress and biofilm infection.

Analyzing the pathogenesis of systemic lupus erythematosus complicated by atherosclerosis using transcriptome data.

Background: Accumulating evidence supports the predisposition of systemic lupus erythematosus (SLE) to atherosclerosis (AS). However, the common pathogenesis of these two diseases remains unclear. This study aimed to explore the mechanisms of SLE complicated by AS. Methods: Gene expression profiles of SLE (GSE50772) and AS (GSE100927) were downloaded from the Gene Expression Omnibus. We analyzed differentially expressed genes (DEGs) of SLE and AS and performed enrichment analyses separately. After analyzing the common DEGs (CDEGs), we performed functional enrichment analysis, protein-protein interaction (PPI) network analysis, and hub genes (HGs) identification of CDEGs. Then, we performed a co-expression analysis of HGs and verified their expression and diagnostic value. We further explored immune cell infiltration and analyzed the correlation between HGs and infiltrating immune cells (IICs). Finally, we verified the reliability of the screening pathway. Results: We obtained 530 DEGs from the GSE50772 dataset and 448 DEGs from the GSE100927 dataset. The results of the enrichment analysis showed that there were many similar immune- and inflammation-related processes between the two diseases. We analyzed 26 CDEGs (two downregulated genes and 24 upregulated genes) and enrichment analysis highlighted the important role of the IL-17 signaling pathway. We identified five HGs (CCR1, CD163, IL1RN, MMP9, and SIGLEC1) using the CytoHubba plugin and HGs validation showed that the five HGs screened were reliable. Co-expression networks showed that five HGs can affect mononuclear cell migration. Immune cell infiltration analysis indicated monocytes in SLE and M0 macrophages in AS accounted for a high proportion of all IICs, and the difference in infiltration was obvious. We also found a significant positive correlation between CCR1, CD163, IL1RN, and MMP9 and monocytes in SLE, and a significant positive correlation between CCR1, IL1RN, MMP9, and SIGLEC1 and M0 macrophages in AS. Pathway validation also demonstrated that the IL-17 signaling pathway was a key pathway for the differentiation of monocytes into macrophages. Conclusions: The five HGs may promote the differentiation of monocytes into macrophages by influencing the IL-17 signaling pathway, leading to SLE complicated by AS. Our study provides insights into the mechanisms of SLE complicated by AS.

Facile preparation of PVA hydrogels with adhesive, self-healing, antimicrobial, and on-demand removable capabilities for rapid hemostasis.

Multifunctional and smart hydrogel-based hemostatic materials are of great significance in the field of medical care. In this paper, a facile method for the preparation of self-healing, adhesive and on-demand removable PBO hydrogels was established with a simple mixture of polyvinyl alcohol (PVA), borax and oligomeric procyanidin (OPC). In this hydrogel system, borax and OPC were used as dynamic crosslinkers to connect the PVA macromolecules through reversible borate ester bonds and hydrogen bonds, resulting in hydrogels that possess good self-healing and adhesive abilities. Furthermore, the PBO hydrogel displayed excellent antimicrobial activity against Escherichia coli and Staphylococcus aureus. In addition, thanks to the adhesive property of the hydrogel and the inherent hemostatic activity of OPC, this hydrogel showed rapid hemostasis performance as concluded from the in vivo experiments of mouse liver incision, tail amputation and femoral artery models. Benefitting from the fast degradation in water, this hydrogel could be easily removed on-demand within 10 min. Therefore, this well-designed PBO hydrogel offers an important prospect as a rapid hemostatic dressing.

Facile preparation of antibacterial hydrogel with multi-functions based on carboxymethyl chitosan and oligomeric procyanidin.

Hydrogel-based antibacterial materials with multi-functions are of great significance for healthcare. Herein, a facile and one-step method was developed to fabricate an injectable hydrogel (named CMCS/OPC hydrogel) based on carboxymethyl chitosan (CMCS) and oligomeric procyanidin (OPC). In this hydrogel system, OPC serves as the dynamic crosslinker to bridge CMCS macromolecules mainly through dynamical hydrogen bonds, which endows this hydrogel with excellent injectable, self-healing, and adhesive abilities. In addition, due to the inherent antibacterial properties of CMCS and OPC, this hydrogel shows excellent antibacterial activity. Therefore, the well-designed CMCS/OPC hydrogel has great prospects as an antibacterial material in the biomedical field.

Injectable and reactive oxygen species-scavenging gelatin hydrogel promotes neural repair in experimental traumatic brain injury.

Oxidative stress caused by the overexpression of reactive oxygen species (ROS) plays an important role in the pathogenesis of traumatic brain injury (TBI). Accumulation of ROS can lead to cell death, neurodegeneration, and neurological deficit. Therefore, the design and application of functional materials with ROS scavenging ability is of great significance for neural repair. Herein, an injectable and antioxidant hydrogel was developed for TBI treatment based on the Schiff base reaction of gallic acid-conjugated gelatin (GGA) and oxidized dextran (Odex). The resulting GGA/Odex hydrogel could effectively scavenge DPPH and ABTS radicals, as well as protect cells from the oxidative damage in vitro. Moreover, GGA/Odex hydrogel possessed well biocompatible features. In a moderate TBI mouse model, in situ implantation of GGA6Odex hydrogel efficiently facilitated neurogenesis and promoted the motor, learning and memory abilities. Also, this composite hydrogel suppressed oxidative stress and inflammation via the activation of Nrf2/HO-1 pathway and the regulating of inflammatory factors secretion and macrophage/microglia polarization. Therefore, this injectable and ROS-scavenging GGA6Odex hydrogel is a promising biomaterial for tissue regenerative medicine, including TBI and other tissue repair relevant to raised ROS circumstance.

Injectable Self-Healing Adhesive Chitosan Hydrogel with Antioxidative, Antibacterial, and Hemostatic Activities for Rapid Hemostasis and Skin Wound Healing.

Engineered wound dressing materials with excellent injectability, self-healing ability, tissue-adhesiveness, especially the ones possessing potential therapeutic effects have great practical significance in healthcare. Herein, an injectable quaternary ammonium chitosan (QCS)/tannic acid (TA) hydrogel based on QCS and TA was designed and fabricated by facile mixing of the two ingredients under physiological conditions. In this system, hydrogels were mainly cross-linked by dynamic ionic bonds and hydrogen bonds between QCS and TA, which endows the hydrogel with excellent injectable, self-healing, and adhesive properties. Benefitting from the inherent antioxidative, antibacterial, and hemostatic abilities of TA and QCS, this hydrogel showed superior reactive oxygen species scavenging activity, broad-spectrum antibacterial ability, as well as rapid hemostatic capability. Moreover, the QCS/TA2.5 hydrogel (containing 2.5% TA) exhibited excellent biocompatibility. The in vivo experiments also showed that QCS/TA2.5 hydrogel dressing not only rapidly stopped the bleeding of arterial and deep incompressible wounds in mouse tail amputation, femoral artery hemorrhage, and liver incision models but also significantly accelerated wound healing in a full-thickness skin wound model. For the great potentials listed above, this multifunctional QCS/TA2.5 hydrogel offers a promising network as a dressing material for both rapid hemostasis and skin wound repair.