Smart Materials in Medicine最新文献

Periodontitis is associated with several systemic diseases, and advanced periodontitis is often linked to an extensive inflammatory microenvironment and irregularly shaped alveolar bone defects. However, eliminating periodontal inflammation in a minimally invasive manner while repairing irregularly shaped bone defects is clinically challenging. In comparison to traditional bone grafts, a thermo-sensitive hydrogel can be injected into deep periodontal pockets, forming and filling the alveolar bone defects in situ. In this study, porous injectable thermo-sensitive hydrogels containing magnesium ions were prepared by adding magnesium particles (MPs) to a glycerophosphate solution and combining this mixture with a chitosan solution. The incorporation of MPs created interconnected pores in the hydrogel, exhibiting high cytocompatibility and maintaining cell viability, proliferation, spreading, and osteogenesis in vitro. Evaluation on an experimental periodontitis rat model, using micro-computed tomography and histological analyses, demonstrated that this Mg²⁺-containing hydrogel effectively reduced periodontal inflammation, inhibited osteoclast activity, and partially repaired inflammation-induced alveolar bone loss. These results suggest that Mg²⁺-containing thermo-sensitive porous hydrogels might be promising candidates for treating periodontitis.

Acromegaly is a challenging medical condition that arises from the excessive production of growth hormones and the insulin-like growth factor 1 in the pituitary gland. While surgery is the primary treatment for acromegaly, medication is increasingly being used in patients who are unsuitable for surgery or have experienced treatment failure. Despite advancements in medical and surgical therapies, the treatment of acromegaly remains challenging. In this research, a three-dimensional (3D) in-vitro cell culture model for pituitary adenoma research was developed using hydrogel fiber meshes (HFMs) and GH3 cells. Electrospun nanofibers based on polyvinyl alcohol and polyacrylic acid were converted into HFMs by hydrogelification with the leaching of electrosprayed cellulose acetate beads for porosity enhancement. GH3 cells grown in the 3D model exhibited increased dispersion and upregulation of the somatostatin receptor subtypes 2 and 5 compared to those grown in traditional 2D cultures, as well as high sensitivity to somatostatin analogs and tumor-like profiles (as indicated by functional assays and transcriptome analysis, respectively). Therefore, the proposed 3D model accurately represents the physiological response to pituitary-adenoma therapeutic agents. This study highlights the potential of HFMs as a versatile platform for 3D in-vitro cell culture models that can be employed for pituitary adenoma research. Moreover, the proposed 3D cell culture model may contribute to a deeper understanding of tumor biology and facilitate the development of effective therapeutic strategies for acromegaly.

Although characterized by high reactive oxygen species (ROS) generation, cancer cells maintain redox homeostasis to avoid severe damage (e.g., DNA, protein, and plasma membrane dysfunction) and facilitate cancer progression. Emerging evidence has indicated that targeting the regulation of redox homeostasis to amplify oxidative stress is of value in cancer therapy. However, therapeutic agents like nucleic acids, small molecular inhibitors, and chemotherapeutic drugs fail to exert effective cancer inhibition due to their low bioavailability, susceptibility to serum enzymes, and inefficiency in cell membrane penetrating. Therefore, specific delivery vectors are required to facilitate the intracellular delivery of anti-tumor drugs. In the past few decades, various engineered nanomaterials have been designed and developed for drug delivery. In particular, rational nanoparticles (NPs) have garnered more attention due to their splendid long circulation ability, modification capacity, and stimulation-responded release. In this review, the methods of ROS generation and ROS-regulated signaling in cancer development were firstly briefly introduced. The anti-oxidant system, including the metabolism shifting and anti-oxidant genes, were next reviewed, and the strategies of NPs-mediated targeted regulation of redox homeostasis were emphatically discussed. The main strategies include NPs-induced delivery of nucleic acids, small molecule inhibitors, chemotherapeutic agents, radiosensitizers, and NPs-induced ROS generation and GSH depletion. The future development of NP-mediated redox dyshomeostasis in cancer therapy and their challenges in clinical translation were finally discussed.

Over the past decades, increasing evidence has indicated that multiple mechanical signals with different magnitude and pattern, including fluid flow-derived shear stress, topology of extracellular matrix (ECM), substrate stiffness, tension or compression, are now emerging as important orchestrators of immune response under physiological and pathophysiological conditions. Correspondingly, the extrinsic mechanical signals may confer the unique mechanophenotypes on cells, which coupled with their immunophenotypes, determines the ultimate type of immune response. Therefore, the concept of mechano-immunological checkpoints is proposed, which concerns the featured mechanical signals and the typical mechanophenotypes of immune cells, making it possible to elucidate and treat immune-associated disease from the mechanical viewpoint.

Since the need for vascular networks to supply oxygen and nutrients while expelling metabolic waste, most cells can only survive within 200 ​μm of blood vessels; thus, the construction of well-developed blood vessel networks is essential for the manufacture of artificial tissues and organs. Three-dimensional (denoted as 3D) printing is a scalable, reproducible and high-precision manufacturing technology. In the past several years, there have been many breakthroughs in building various vascularized tissues, greatly promoting the development of biological tissue engineering. This paper highlights the latest progress of 3D printed vascularized tissues and organs, including the heart, liver, lung, kidney, and penis. We also discuss the application status and potential of the above printed tissues, and prospect the further requirement of 3D printing technology for manufacturing clinically useable vascularized tissues.

Lung cancer has surpassed other types of cancer to become the primary cause of cancer-related deaths. Surgery stands as the foremost clinical treatment strategy available for tackling this condition, but it receives a low efficiency for most patients. In recent years, some adjuvant therapies are employed to improve the lung cancer treatment efficiency, such as chemotherapy, targeted therapy and immunotherapy. However, these strategies have not significantly increased overall survival of patients. Additionally, the random distribution of drugs will induce severe side effects. Nanomedicines have got great attentions to boost drug effect and reduce adverse reactions, including liposome-based nanoparticles, polymeric nanoparticles, inorganic nanoparticles, and exosomes. Importantly, nanomedicines contribute to improving drug bioavailability, stability and residency in target regions. Benefiting from the physiological characteristics of lung, the inhaled pulmonary delivery strategy in combination with nanomedicine will provide a non-invasive and effective strategy for treating lung cancer. Furthermore, the use of targeting ligands enables precise delivery of loaded drugs to lung cancer cells. Inhaled nanomedicine exhibits unique distribution and sustained release behaviors in the alveoli, amplifying the therapeutic effect and reducing side effects. This review aims to discuss various inhaled methods of delivering nanomedicine to treat lung cancer and also summarizes the clearance mechanism of nanomedicine in the lung. Overall, this review focuses on the application of different inhalable nanomedicines, which may inspire the development of more effective treatments against lung cancer.

Chronic non-healing wounds induced by oxidative stress and inflammation can activate inflammatory cells and produce large amounts of inflammatory mediators, which fail to maintain homeostasis in the skin and delay the wound-healing process. To tackle this issue, heparin-loaded hierarchical composite scaffolds comprised of electrospun fibers and electrosprayed microspheres were prepared to act as an effective anti-inflammatory wound dressing. Microspheres with different electrosprayed densities were deposited into the surface of the electrospun fibers for the improvement of surface topographical cues and cellular activities. The results indicated that the electrospun fibers followed by electrosprayed for 3 ​min to fabricate the composite fiber/microsphere scaffolds contributed to the best performance in terms of promoting cellular activities, with no obvious cytotoxicity, good adhesion morphology, and the fastest cell migration rate. In addition, a suitable amount of heparin was added to the composite scaffolds to alleviate inflammation. The significant adsorption efficiency of heparin-loaded composite scaffolds on inflammatory mediator MCP-1 indicates a favorable anti-inflammation effect in vitro. Furthermore, the heparin-loaded hierarchical scaffolds accelerated the pace of inflammatory wound healing in vivo when compared to commercial 3 ​M Tegaderm and non-heparin-loaded scaffolds. Our work provided a facile strategy for fabricating heparin-loaded hierarchical fiber/microsphere scaffolds to modulate cellular activities via topographical cues and accelerating the inflammatory wound healing process by electrostatic interactions between heparin and MCP-1. These findings suggested that the heparin-loaded hierarchical scaffold was expected to be a promising dressing for inflammatory wound healing.

Blood-contacting medical devices, such as vascular stents, intravascular catheters, and artificial heart valves, frequently encounter complications in clinical practice, including thrombosis, inflammatory reactions, and infections. These challenges pose significant obstacles in the effective application of blood-contacting medical devices. Given that protein adhesion serves as the primary trigger for detrimental events upon contact with blood, this review focuses on various anti-fouling coating strategies aimed at inhibiting protein adsorption. Currently, surface modification of blood-contacting medical devices primarily involves the construction of active or passive anti-fouling coatings. This review explores the implementation of active and passive anti-fouling coating strategies utilizing chemistry, physics, and biotechnology. Examples of anti-fouling coatings discussed include hydrophilic polymer coatings, zwitterionic polymer coatings, superhydrophobic coatings, and composite coatings. Furthermore, we propose implementation approaches for these coatings to address inflammation and infection challenges associated with blood-contacting devices. The review concludes with a brief overview of current surface modification technologies employed in commercial anti-fouling coatings and offers insights into the future of anti-fouling coating technologies for blood-contacting material surfaces. These advancements are essential for the advancement of design, development, and application of blood-contacting materials.

Various factors can cause skin defects, resulting in the loss of physiological functions and even death due to severe concurrent infection. Dressings are often clinically used to fully cover the wounds to improve healing. Hydrogel wound dressings can be loaded with therapeutic compounds (e.g., curcumin) within their three-dimensional networks to enable the in situ delivery of compounds at skin defects for wound healing. In recent decades, natural herbal active components have gradually gained worldwide recognition owing to their safe and diverse therapeutic effects, and an increasing number of bioactive components can be loaded into hydrogels or directly act as hydrogel matrices to enhance safety and achieve the desired therapeutic effects. In this review, twelve bioactive compounds from natural Chinese herbs that can promote wound healing and their mechanism of action are summarized, and the latest research progress in the use of Chinese herbal hydrogels for wound treatment is reviewed.