Injectable gelatin/oxidized dextran hydrogel loaded with apocynin for skin tissue regeneration.

Acute skin injury should be treated in time, due to many factors will affect the normal healing process of wounds, hinder tissue regeneration, and eventually form chronic wounds. Herein, an injectable, in-situ gel-forming hydrogel has been fabricated. The hydrogel is stabilized by dynamic Schiff base and composed of gelatin (Gel), oxidized dextran (Odex) and apocynin (Apo). In vitro studies have shown that this hydrogel has good injectability, plasticity, self-healing and efficient hemostatic properties. The hydrogel has good cytocompatibility with HaCaT and L929 cells by the Live/Dead cell staining. Furthermore, in vivo studies have shown that hydrogel loaded with APO can accelerate angiogenesis and skin tissue regeneration by reducing wound inflammation. Therefore, the injectable Gel/Odex/Apo hydrogel has the advantages of simple preparation process, convenient use and multifunction, etc., it is a promising wound dressing for full-thickness skin repair and has great potential in the field of skin tissue regeneration.

Injectable multifunctional CMC/HA-DA hydrogel for repairing skin injury.

Injectable Hydrogels with adhesive, antioxidant and hemostatic properties are highly desired for promoting skin injury repair. In this study, we prepared a multi-functional carboxymethyl chitosan/hyaluronic acid-dopamine (CMC/HA-DA) hydrogel, which can be crosslinked by horseradish peroxidase and hydrogen peroxide. The antioxidation, gelation time, degradability, rheology and antihemorrhagic properties of hydrogels can be finely tuned by varying composition ratio. The cytocompatibility test and hemolysis test confirmed that the designed hydrogel holds good biocompatibility. More importantly, the repair effect of the hydrogel on full-thickness skin injury model in mice was studied. The results of wound healing, collagen deposition, immunohistochemistry and immunofluorescence showed that CMC/HA-DA hydrogel could significantly promote angiogenesis and cell proliferation at the injured site. Notably, the inflammatory response can also be regulated to promote the repair of full-thickness skin defect in mice. Results indicate that this injectable CMC/HA-DA hydrogel holds high application prospect for promising wound healing.

The Development of Hyaluronic Acids Used for Skin Tissue Regeneration.

Burns, mechanical injuries, skin defects, poor wound healing and scars caused by chronic diseases are serious clinical issues that affect millions of people around the world. Hyaluronic acid (HA) is one of the main components of extracellular matrix, which is widely distributed in human body. Because of its unique physical and chemical properties and diversity of physiological functions, hyaluronic acid is widely used in tissue engineering and regenerative medicine. This paper reviews the application of HA and HA based scaffolds in the regeneration and repair of skin tissue, as well as the application of HA in the fields of skin filler, wound healing, beauty, etc.

Aloe vera: A Medicinal Plant Used in Skin Wound Healing.

Skin injury is a major problem threatening human physical and mental health, and how to promote wound healing has been the focus. Developing new wound dressings is an important strategy in skin regeneration. Aloe vera is a medicinal plant with a long history, complex constituents, and various pharmacological activities. Many studies have shown that A. vera plays an important role in promoting wound healing. Adding A. vera to wound dressing has become an ideal way. This review will describe the process of skin injury and wound healing and analyze the role of A. vera in wound healing. In addition, the types of wound dressing and the applications of A. vera in wound dressing will be discussed.

Nanomaterials for Angiogenesis in Skin Tissue Engineering.

Damage to skin tissue, which causes the disorder of the patient's body homeostasis, threatens the patient's life and increases the personal and social treatment burden. Angiogenesis, a key step in the wound healing process, provides sufficient oxygen and nutrients to the wound area. However, traditional clinical interventions are not enough to stabilize the formation of the vascular system to support wound healing. Due to the unique properties and multiple functions of nanomaterials, it has made a major breakthrough in the application of medicine. Nanomaterials provide a more effective treatment to hasten the angiogenesis and wound healing, by stimulating fundamental factors in the vascular regeneration phase. In the present review article, the basic stages and molecular mechanisms of angiogenesis are analyzed, and the types, applications, and prospects of nanomaterials used in angiogenesis are detailed. Impact statement Wound healing (especially chronic wounds) is currently a clinically important issue. The long-term nonhealing of chronic wounds often plagues patients, medical systems, and causes huge losses to the social economy. There is currently no effective method of treating chronic wounds in the clinic. Angiogenesis is an important step in wound healing. Nanomaterials had properties that are not found in conventional materials, and they have been extensively studied in angiogenesis. This review article provides readers with the molecular mechanisms of angiogenesis and the types and applications of angiogenic nanomaterials, hoping to bring inspiration to overcome chronic wounds.

Preparing Sodium Alginate/Polyethyleneimine Spheres for Potential Application of Killing Tumor Cells by Reducing the Concentration of Copper Ions in the Lesions of Colon Cancer.

Inhibition of residual malignant tumors in patients with colon cancer after operation is one of the difficulties in rehabilitation treatment. At present, using biocompatible materials to remove the copper ion which is the growth dependence of malignant tumors in the lesion site is considered to be the frontier means to solve this problem. In this work, we developed a sodium alginate (SA)/polyethyleneimine (PEI) hydrogel sphere via cross-linking method (SA/SP/SA; SP = SA/PEI) as an oral biomaterial for adsorbing and removing copper ions from colon cancer lesions. The evaluated results showed that the SA/PEI/SA (SPS) hydrogel sphere obtained the largest swelling rate at pH 8.3 which was the acid-base value of colon microenvironment and absorbed more copper ions compared with the SA control. The cell experiment presented that the SPS hydrogel sphere owned better compatibility on normal fibroblasts and promoted higher death of colon cancer cells compared with SA/PEI (SP) and SA control. Our data suggested that the SA/PEI hydrogel sphere had the potentiality as an oral biomaterial for inhibiting colon cancer cells.