Photothermal antibacterial materials to promote wound healing.

Wound healing is a crucial process that restores the integrity and function of the skin and other tissues after injury. However, external factors, such as infection and inflammation, can impair wound healing and cause severe tissue damage. Therefore, developing new drugs or methods to promote wound healing is of great significance. Photothermal therapy (PTT) is a promising technique that uses photothermal agents (PTAs) to convert near-infrared radiation into heat, which can eliminate bacteria and stimulate tissue regeneration. PTT has the advantages of high efficiency, controllability, and low drug resistance. Hence, nanomaterial-based PTT and its related strategies have been widely explored for wound healing applications. However, a comprehensive review of PTT-related strategies for wound healing is still lacking. In this review, we introduce the physiological mechanisms and influencing factors of wound healing, and summarize the types of PTAs commonly used for wound healing. Then, we discuss the strategies for designing nanocomposites for multimodal combination treatment of wounds. Moreover, we review methods to improve the therapeutic efficacy of PTT for wound healing, such as selecting the appropriate wound dressing form, controlling drug release, and changing the infrared irradiation window. Finally, we address the challenges of PTT in wound healing and suggest future directions.

Mesoporous carbon nanoenzyme as nano-booster for photothermal-enhanced photodynamic therapy compared with graphene oxide.

The over-expressed GSH in tumor microenvironment significantly weakens the lethal reactive oxygen species (ROS) generated by photodynamic therapy (PDT) and catalysis of nanoenzyme. Hence, it is necessary to excavate a versatile and effective vehicle with oxidative stress-enhancement and GSH-depletion capacity to break the redox homeostasis in tumor microenvironment. GO has been reported to possess GSH-depletion and peroxidase (POD)-like capacity. Based on this, PEGylated mesoporous carbon (MC-PEG) was prepared as ICG vehicle to compare with PEGylated graphene oxide (GO-PEG). Excitingly, MC-PEG was found to exhibit three times higher oxidative capacity by POD-like process than GO-PEG, and owned more effective and continuous GSH-depletion capacity to further amplify the oxidative stress. Meanwhile, MC-PEG exhibited better protective effect on the loaded ICG against unwanted light excitation than GO-PEG. Together with the higher photothermal conversion effect, under the NIR light irradiation, MC-PEG could markedly improve the temperature of tumor cells and produce more hydroxyl radical, continuously consume GSH and provide more better protection for ICG compared with GO-PEG, thus further boosting the combination of photothermal and photodynamic effects. The anti-tumor experiment in cell and in-vivo level both validated that ICG/MC-PEG showed better synergistic effect with lower IC50 value and higher tumor suppression rate than ICG/GO-PEG.

A mutually beneficial macrophages-mediated delivery system realizing photo/immune therapy.

The accumulation of nanomedicines in tumor tissues determines their therapeutic efficacy. We herein exploit the tropism of macrophages to improve the accumulation and retention time of nanomedicine at tumors. Interestingly, macrophages are not merely as transporters, but killers activated by nanomedicine. The system(M@C-HA/ICG) was established by decorating macrophages with hyaluronic acid-modified hollow mesoporous carbon (C) nanoparticles loading indocyanine green (ICG). Notably, C nanoparticles with superior photothermal conversion capability not merely guarantee the efficient delivery of ICG through high drug loading efficiency and inhibiting the premature leaky, but effectually activate the polarization of macrophages. The results exhibited that those activated macrophages could release pro-inflammatory cytokines (NO, TNF-α, IL-12), while M@C-HA/ICG afforded about 2-fold higher tumor accumulation compared with pure nanoparticle C-HA/ICG and produced heat and singlet oxygen (1O2) under irradiation of an 808 nm laser, realizing the combination of photodynamic therapy (PDT), photothermal therapy (PTT) and cytokines-mediated immunotherapy. Specially, we also investigated the relationship of singlet oxygen (1O2) or temperature and tumor-killing activity for understanding the specific effectual procedure of PDT/PTT synergistic therapy. Overall, we firstly established an "all active" delivery system integrating the features of nanomedicine with biological functions of macrophages, providing a novel insight for cell-mediated delivery platform and tumor targeted multimodality anti-cancer therapy.

Current trends in smart mesoporous silica-based nanovehicles for photoactivated cancer therapy.

Photoactivated therapeutic strategies (photothermal therapy and photodynamic therapy), due to the adjusted therapeutic area, time and light dosage, have prevailed for the fight against tumors. Currently, the monotherapy with limited treatment effect and undesired side effects is gradually replaced by multimodal and multifunctional nanosystems. Mesoporous silica nanoparticles (MSNs) with unique physicochemical advantages, such as huge specific surface area, controllable pore size and morphology, functionalized modification, satisfying biocompatibility and biodegradability, are considered as promising candidates for multimodal photoactivated cancer therapy. Excitingly, the innovative nanoplatforms based on the mesoporous silica nanoparticles provide more and more effective treatment strategies and display excellent antitumor potential. Given the rapid development of antitumor strategies based on MSNs, this review summarizes the current progress in MSNs-based photoactivated cancer therapy, mainly consists of (1) photothermal therapy-related theranostics; (2) photodynamic therapy-related theranostics; (3) multimodal synergistic therapy, such as chemo-photothermal-photodynamic therapy, phototherapy-immunotherapy and phototherapy-radio therapy. Based on the limited penetration of irradiation light in photoactivated therapy, the challenges faced by deep-seated tumor therapy are fully discussed, and future clinical translation of MSNs-based photoactivated cancer therapy are highlighted.

Polydopamine-carbon dots functionalized hollow carbon nanoplatform for fluorescence-imaging and photothermal-enhanced thermochemotherapy.

The low power photothermal therapy can reduce the tissue damage caused by laser irradiation, thus the near-infrared (NIR) absorbing vehicles with high photothermal conversion efficiency are demanded in the low power treatment. Herein, the NIR-absorbing agent polydopamine (PDA) and carbon dots (CDs) were gated on the openings of hollow mesoporous carbon (HMC) to construct a photothermal enhanced multi-functional system (HMC-SS-PDA@CDs). Interestingly, the fluorescence emission wavelength of HMC-SS-PDA@CDs was red-shifted by FRET effect between PDA and CDs, which solved the dilemma of fluorescence quenching of carbon-based materials and was more conducive to cell imaging. The modification of PDA@CDs not only acts as the gatekeepers to realize multi-responsive release of pH, GSH and NIR, but also endows the HMC vehicle with excellent photothermal generation capacity, the possibility for bio-imaging as well as the enhanced stability. Naturally, both the cytological level and the multicellular tumor sphere level demonstrate that the delivery system has good low-power synergistic therapeutic with combination index (CI) of 0.348 and imaging effects. Meanwhile, the combined treatment group showed the highest tumor inhibition rate of 92.6% at 0.75 W/cm2. Therefore, DOX/HMC-SS-PDA@CDs nano-platform had broad application prospects in low power therapy and convenient imaging of carbon-based materials.

[Meridian three-combined therapy for treatment of ordinary psoriasis: a multi-center randomized controlled study].

OBJECTIVE: To evaluate the effectiveness and safety of the meridian three-combined therapy for treatment of ordinary psoriasis. METHODS: A multi-central, randomized and positive drug controlled trial was adopted, and 233 cases were divided into an observation group of 116 cases and a control group of 117 cases. The observation group was treated with thread embedding at points, blood-letting puncture on the back of ear and auricular point pressing (i.e. meridian three-combined therapy). For thread embedding, 3-4 local points such ear points as Fei (CO14), Gan (CO12), Pizhixia (AT4), Shenmen (TF4) , cephalic and symmetric points of severe parts of the limb skin were selected according to the skin lesion position, and the treatment was given once each two weeks. For ear point tapping and pressing, 3-5 points were selected in each session. And the control group was treated with oral administration of Di yin Tablets, 5 tablets each time, twice each day. After treatment of 6 weeks, the clinical therapeutic effects, the score of skin lesion area, the scores for skin lesion severity and safety were compared in the two groups. RESULTS: The markedly effective rate was 57.8 % in the observation group and 51.3% in the control group with no significant difference between the two groups (P>0.05); after treatment the scores for both the skin lesion area and the skin lesion severity were significantly decreased in the two groups compared with those before treatment (P<0.01), and with a significant difference between the two groups (P>0.05). And the incidence rate of the adverse reaction in the observation group was significantly lower than that in the control group. CONCLUSION: The meridian three-combined therapy is effective and safe for treatment of ordinary psoriasis.