Real-time detection of intracellular reactive oxygen species and mitochondrial membrane potential in THP-1 macrophages during ultrasonic irradiation for optimal sonodynamic therapy

Metal-organic framework-mediated siRNA delivery and sonodynamic therapy for precisely triggering ferroptosis and augmenting ICD in osteosarcoma

The complex genomics, immunosuppressive tumor microenvironment (TME), and chemotherapeutic resistance of osteosarcoma (OS) have resulted in limited therapeutic effects in the clinic. Ferroptosis is involved in tumor progression and is regulated mainly by glutathione peroxidase 4 (GPX4). Small interfering RNA (siRNA)-based RNA interference (RNAi) can precisely target any gene. However, achieving effective siRNA delivery is highly challenging. Here, we fabricated a TME-responsive metal-organic framework (MOF)-based biomimetic nanosystem (mFeP@si) with siGPX4 delivery and sonodynamic therapy (SDT) to treat OS by targeting ferroptosis. Under ultrasound (US) irradiation, mFeP@si achieves lysosomal escape via singlet oxygen (1O2)-mediated lysosomal membrane disruption and then accelerates ROS generation and glutathione (GSH) depletion. Meanwhile, siGPX4 silences GPX4 expression by binding to GPX4 mRNA and leads to the accumulation of toxic phospholipid hydroperoxides (PL-OOH), further magnifying the ROS storm and triggering ferroptosis. Notably, synergistic therapy remarkably enhances antitumor effects, improves the immunosuppressive TME by inducing potent immunogenic cell death (ICD), and increases the sensitivity of chemotherapy-resistant OS cells to cisplatin. Overall, this novel nanosystem, which targets ferroptosis by integrating RNAi and SDT, exhibits strong antitumor effects both in vitro and in vivo, providing new insights for treating OS.

Hexadecanoic acid produced in the co-culture of S. cerevisiae and E.coli promotes oxidative stress tolerance of the S.cerevisiae cells

Co-fermentation performed by Saccharomyces cerevisiae and Escherichia coli or other microbes has been widely used in industrial fermentation. Meanwhile, the co-cultured microbes might regulate each other's metabolisms or cell behaviors including oxidative stress tolerance through secreting molecules. Here, results based on the co-culture system of S. cerevisiae and E. coli suggested the promoting effect of E. coli on the oxidative stress tolerance of S. cerevisiae cells. The co-cultured E. coli could enhance S. cerevisiae cell viability through improving its membrane stability and reducing the oxidized lipid level. Meanwhile, promoting effect of the co-cultured supernatant on the oxidative stress tolerance of S. cerevisiae illustrated by the supernatant substitution strategy suggested that secreted compounds contained in the co-cultured supernatant contributed to the higher oxidative stress tolerance of S. cerevisiae. The potential key regulatory metabolite (i.e., hexadecanoic acid) with high content difference between co-cultured supernatant and the pure-cultured S. cerevisiae supernatant was discovered by GC-MS-based metabolomics strategy. And exogenous addition of hexadecanoic acid did suggest its contribution to higher oxidative stress tolerance of S. cerevisiae. Results presented here would contribute to the understanding of the microbial interactions and provide the foundation for improving the efficiency of co-fermentation performed by S. cerevisiae and E. coli.

Sonodynamic therapy for the treatment of atherosclerosis

Atherosclerosis (AS) is a chronic inflammatory disease of large and medium-sized arteries that leads to ischemic heart disease, stroke, and peripheral vascular disease. Despite the current treatments, mortality and disability still remain high. Sonodynamic therapy (SDT), a non-invasive and localized methodology, has been developed as a promising new treatment for inhibiting atherosclerotic progression and stabilizing plaques. Promising progress has been made through cell and animal assays, as well as clinical trials. For example, the effect of SDT on apoptosis and autophagy of cells in AS, especially macrophages, and the concept of non-lethal SDT has also been proposed. In this review, we summarize the ultrasonic parameters and known sonosensitizers utilized in SDT for AS; we elaborate on SDT's therapeutic effects and mechanisms in terms of macrophages, T lymphocytes, neovascularization, smooth muscle cells, lipid, extracellular matrix and efferocytosis within plaques; additionally, we discuss the safety of SDT. A comprehensive summary of the confirmed effects of SDT on AS is conducted to establish a framework for future researchers.

Ultrasonic cavitation induced Vibrio parahaemolyticus entering an apoptosis-like death process through SOS response

As an effective non-thermal sterilization method, ultrasound remains at the level of passive bacterial death despite the initial understanding of its sterilization mechanism. Here, we present the perspective that bacteria can choose to actively enter an apoptosis-like death state in response to external ultrasonic stress. In this study, Vibrio parahaemolyticus exhibited apoptotic markers such as phosphatidylserine ectropion and activated caspases when subjected to ultrasound stress. Additionally, the accumulation of reactive oxygen species (ROS) and enhanced calcium signaling were observed. Further transcriptomic analysis was conducted to investigate the regulatory mechanism of the SOS response in Vibrio parahaemolyticus during an apoptosis-like state. The results showed that the genes encoding the citrate cycle were down-regulated in Vibrio parahaemolyticus cells adapted to ultrasonic stress, leading to an apoptosis-like state and a decrease in production capacity and ability to catabolize carbon dioxide. Furthermore, the level of oxidized glutathione increased, suggesting that the bacteria were engaged in various anti-oxidative stress responses, ultimately leading to apoptosis. Moreover, the ultrasound field activated the regulatory factor CsrA, which facilitates stress survival as cells transition from rapid growth to an apoptotic state through a stringent response and catabolic inhibition system. Parallel reaction monitoring (PRM) revealed that the expression of certain key SOS proteins in Vibrio parahaemolyticus was up-regulated following ultrasound treatment, resulting in a gradual adaptation of the cells to external stress and ultimately leading to active cell death. In conclusion, the biological lethal effect of ultrasound treatment is not solely a mechanical cell necrosis process as traditionally viewed, but also a programmed cell death process regulated by cellular adaptation. This enriched the biological effect pathway of ultrasound sterilization.

Macrophage-targeted ultrasound nanobubbles for highly efficient sonodynamic therapy of atherosclerotic plaques by modulating M1-to-M2 polarization

BACKGROUND AND AIMS

Sonodynamic therapy (SDT) is a new approach for the treatment of atherosclerosis (AS), yet the poor targeting ability of sonosensitizers limits its therapeutic efficacy. Herein, we reported a plaque-targeted nanoplatform modified with macrophage type A scavenger receptor (SR-A)-targeted peptide (designated as SR-A-Ce6NB) to augment the efficacy of low-intensity pulsed ultrasound (LIPUS)-mediated SDT of atherosclerotic plaque.

METHODS

SR-A-Ce6NB was fabricated by thin hydration method and biotin-avidin system, and its physicochemical properties, biocompatibility and plaque-targeting ability were investigated. RAW 264.7 cells were used for in vitro experimental studies. Male 6-week-old apolipoprotein E-deficient mice were fed a high-fat diet for 16 weeks to induce aortic atherosclerotic plaques. Plaque-bearing mice were randomly allocated into five groups (n = 6): control group, Ce6 + LIPUS group, Ce6NB + LIPUS group, SR-A-Ce6NB + LIPUS group and atorvastatin group. After treatment in each group, the aortic artery was harvested for Oil red O, H&E, Masson's trichrome staining, immunohistochemical and immunofluorescent staining.

RESULTS

SR-A-Ce6NB with high stability and excellent biocompatibility was successfully fabricated. SR-A-Ce6NB could actively target activated macrophages and selectively accumulate in the plaque. SR-A-Ce6NB could be triggered by LIPUS and had a more potent sonodynamic effect than free Ce6 to potentiate SDT. SR-A-Ce6NB-mediated SDT enhanced the anti-atherogenic effect via modulating M1-to-M2 macrophage polarization and had an earlier onset of action on plaque than the statin-mediated effect. No apparent side effect was observed after intravenous SR-A-Ce6NB injection and LIPUS exposure.

CONCLUSIONS

Macrophage-targeted nanoplatform SR-A-Ce6NB-mediated SDT provides a safe, effective and preferable anti-atherogenic therapy by mediating M1-to-M2 macrophage polarization.

Tumor Targeting with Apatinib-loaded Nanoparticles and Sonodynamic Combined Therapy

INTRODUCTION

This study implies the enhancement of apatinib killing effect in 4T1 tumor cells through constructing drug-loaded nanoparticles apatinib/Ce6@ZIF- 8@Membranes (aCZM) to enhance tumor therapeutic targeting and reduce toxic side following sonodynamic therapy (SDT).

METHODS

apatinib/Ce6@ZIF-8 (aCZ) were synthesized by in situ encapsulation, and aCZM were constructed by encapsulating the nanoparticles with extracted breast cancer 4T1 cell membranes. aCZM were characterized and tested for the stability by electron microscopy, and the membrane proteins on the nanoparticles' surface were assessed using SDS-PAGE gel electrophoresis. The cell viability of 4T1 cells following treatment with aCZM was tested using cell counting kit-8 (CCK-8). The uptake of nanoparticles was detected by laser confocal microscopy and flow cytometry, and the SDT-mediated production of reactive oxygen species (ROS) was verified by singlet oxygen sensor green (SOSG), electron spin resonance (ESR), and DCFH-DA fluorescent probes. The CCK-8 assay and flow cytometry using Calcein/PI were used to assess the antitumoral effect of aCZM nanoparticles under SDT. The biosafety of aCZM was further verified in vitro and in vivo using the hemolysis assay, routine blood test and H&E staining of vital organs in Balb/c mice.

RESULTS

aCZM with an average particle size of about 210.26 nm were successfully synthesized. The results of the SDS-PAGE gel electrophoresis experiment showed that aCZM have a band similar to that of pure cell membrane proteins. The CCK-8 assay demonstrated the absence of effects on cell viability at a low concentration range, and the relative cell survival rate reached more than 95%. Laser confocal microscopy and flow cytometry analysis showed that aCZM treated group has the strongest fluorescence and the highest cellular uptake of nanoparticles. SOSG, ESR, and DCFH-DA fluorescent probes all indicated that the aCZM + SDT treated group has the highest ROS production. The CCK-8 assay also showed that when the ultrasound intensity was fixed at 0.5 W/cm2, the relative cell survival rates in the medium concentration group (10 μg/ml) (5.54 ± 1.26%) and the high concentration group (20 μg/ml) (2.14 ± 1.63%) were significantly lower than those in the low concentration group (5 μg/ml) (53.40 ± 4.25%). Moreover, there was a concentration and intensity dependence associated with the cellkilling effect. The mortality rate of the aCZM in the ultrasound group (44.95 ± 3.03%) was significantly higher than that of the non-ultrasound (17.00 ± 2.26%) group and aCZ + SDT group (24.85 ± 3.08%) (P<0.0001). The live and dead cells' staining (Calcein/PI) also supported this result. Finally, in vitro hemolysis test at 4 and 24 hours showed that the hemolysis rate of the highest concentration group was less than 1%. The blood routine, biochemistry, and H&E staining results of major organs in Balb/c mice undergoing nano-treatments showed no obvious functional abnormalities and tissue damage in 30 days.

CONCLUSION

In this study, a multifunctional bionic drug delivery nanoparticles (aCZM) system with good biosafety and compatibility in response to acoustic dynamics was successfully constructed and characterized. This system enhanced apatinib killing effect on tumor cells and reduced toxic side effects under SDT.

Carbonized polymer dots derived from metformin and L-arginine for tumor cell membrane- and mitochondria-dual targeting therapy

Metformin has demonstrated antitumor potential in clinical studies; however, achieving optimal antitumor effects requires administering an extremely safe medication dose. To enhance the efficacy and reduce dosage requirements, we propose the creation of large-molecule drugs through the combination of small-molecule drugs. In this study, we developed novel polymer dots, referred to as MA-dots, with sizes of approximately 5 nm, featuring dual targeting capabilities for tumor cell membranes and mitochondria. MA-dots were synthesized using metformin and L-arginine via a rapid microwave-assisted method. Notably, the resulting MA-dots (with a half maximal inhibitory concentration (IC50) of 93.60 μg mL-1) exhibited more than a 12-fold increase in antitumor activity compared to the raw metformin material (IC50 = 1159.00 μg mL-1) over a 24-hour period. In addition, our MA-dots outperformed most metformin-derived nanodrugs in terms of antitumor efficacy. Furthermore, oral gavage treatment with MA-dots led to the suppression of A549 (lung cancer cell lines) tumor growth in vivo. Mechanistic investigations revealed that MA-dots bound to the large neutral amino acid transporter 1 (LAT1) proteins, which are overexpressed in malignant tumor cell membranes. Moreover, these MA-dots accumulated within the mitochondria, leading to increased production of reactive oxygen species (ROS), mitochondrial damage, and disruption of energy metabolism by modulating the 5'-adenosine monophosphate-activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR) pathway in tumor cells. This cascade of events triggers cell-cycle arrest and apoptosis. In summary, this study presented a rapid method for fabricating a novel nanoderivative, MA-dots, capable of both tumor targeting and exerting tumor-suppressive effects.

Ultrasound nanotheranostics: Toward precision medicine

Ultrasound (US) is a mechanical wave that can penetrate biological tissues and trigger complex bioeffects. The mechanisms of US in different diagnosis and treatment are different, and the functional application of commercial US is also expanding. In particular, recent developments in nanotechnology have led to a wider use of US in precision medicine. In this review, we focus on US in combination with versatile micro and nanoparticles (NPs)/nanovesicles for tumor theranostics. We first introduce US-assisted drug delivery as a stimulus-responsive approach that spatiotemporally regulates the deposit of nanomedicines in target tissues. Multiple functionalized NPs and their US-regulated drug-release curves are analyzed in detail. Moreover, as a typical representative of US therapy, sonodynamic antitumor strategy is attracting researchers' attention. The collaborative efficiency and mechanisms of US and various nano-sensitizers such as nano-porphyrins and organic/inorganic nanosized sensitizers are outlined in this paper. A series of physicochemical processes during ultrasonic cavitation and NPs activation are also discussed. Finally, the new applications of US and diagnostic NPs in tumor-monitoring and image-guided combined therapy are summarized. Diagnostic NPs contain substances with imaging properties that enhance US contrast and photoacoustic imaging. The development of such high-resolution, low-background US-based imaging methods has contributed to modern precision medicine. It is expected that the integration of non-invasive US and nanotechnology will lead to significant breakthroughs in future clinical applications.

Advances in imaging and treatment of atherosclerosis based on organic nanoparticles

Atherosclerosis, a systemic chronic inflammatory disease, can lead to thrombosis and vascular occlusion, thereby inducing a series of serious vascular diseases. Currently, distinguishing unstable plaques early and achieving more effective treatment are the two main clinical concerns in atherosclerosis. Organic nanoparticles have great potential in atherosclerotic imaging and treatment, showing superior biocompatibility, drug-loading capacity, and synthesis. This article illustrates the process of atherosclerosis onset and the key targeted cells, then systematically summarizes recent progress made in organic nanoparticle-based imaging of different types of targeted cells and therapeutic methods for atherosclerosis, including optical and acoustic-induced therapy, drug delivery, gene therapy, and immunotherapy. Finally, we discuss the major impediments that need to be addressed in future clinical practice. We believe this article will help readers to develop a comprehensive and in-depth understanding of organic nanoparticle-based atherosclerotic imaging and treatment, thus advancing further development of anti-atherosclerosis therapies.

Sonodynamic Therapy With Concentric Ultrasound Imaging Array for Precision Theranostics for Atherosclerotic Plaque

Atherosclerotic cardiovascular disease is a major cause of human disability and mortality. Our previous study demonstrated the safety and efficacy of sonodynamic therapy (SDT) on atherosclerotic plaques. However, traditional single-element therapeutic transducer has single acoustic field, and positioning therapeutic and imaging transducers in the same position is difficult during ultrasound imaging-guided SDT. Continuously changing the position of transducers to intervene lesions in different positions is required, increasing the difficulty of treatment. Thus, an SDT device with precise theranostics is required. Therefore, we designed and fabricated a "concentric ultrasound transducer for theranostics" (CUST-T), comprising a central 8-MHz linear array transducer for ultrasound imaging, and a peripheral 1-MHz hollow two-dimensional (2-D) planar array transducer for generating phased-array focused ultrasound (PAFUS). The CUST-T exhibited high imaging resolution at a distance of up to 20 mm from the transducer and could generate a personalized complex PAFUS acoustic field to match various lesions. In vitro biomedical results showed that PAFUS-SDT induced RAW264.7-derived foam cell apoptosis leading to a targeting field apoptotic rate 4.36-6.24 times that of the nontargeting field and the significant apoptotic region was consistent with the PAFUS acoustic field. In vivo, PAFUS-SDT guided by ultrasound imaging significantly increased the lumen area ( ) and collagen level ( ), whereas the wall thickness ( ) and lipid content ( ) of rabbit femoral artery were reduced. In conclusion, CUST-T provided image guidance sufficient for accurate SDT for atherosclerotic plaques in peripheral arteries and could be applied in clinical practice.

Exploiting Shock Waves to Trigger the Anticancer Sonodynamic Activity of 5-Aminolevulinc Acid-Derived Protoporphyrin IX on In Vitro 2D and 3D Cancer Models

Sonodynamic therapy (SDT) is a noninvasive method for cancer treatment based on selective activation of a sonosensitiser by ultrasound (US), which results in the generation of reactive oxygen species (ROS) and cancer cell death. SDT uses a similar approach to photodynamic therapy (PDT), but can overcome the main drawback of PDT, i.e., poor tissue penetration of light. This research work investigated the anticancer effect of SDT on various two- (2D) and three-dimensional (3D) in vitro tumour models, using PDT as a reference treatment. Sonodynamic experiments were performed with pulsed US, specifically with shock waves (SW) and the prodrug 5-aminolevulinic acid (Ala), which is converted-at the mitochondrial level-into the sonosensitiser protoporphyrin IX (PPIX). SW-mediated PPIX sonodynamic activation resulted in a significant decrease in cell proliferation, especially on human fibrosarcoma (HT-1080) cells, where PPIX accumulation was higher compared to human melanoma (A2058) and neuroblastoma (SH-SY5 Y) cells. Moreover, SW-mediated SDT showed significant ROS generation, cell line-dependent in its amount, probably due to differences in Ala-induced PPIX synthesis. In all cancer cell lines, apoptosis was highlighted as the main cancer cell death pathway determined by SW-mediated SDT, along with significant cytochrome c release, and a consequent increase in DNA damage. The efficacy of SDT with SW and Ala in halting cancer cell proliferation was also confirmed in 3D cancer spheroids. The present study suggests that SW-mediated SDT is a valuable approach to slow down tumour proliferation, thus opening an innovative scenario in cancer treatment.

Sonodynamic Effects of a Novel Ether-Group Modified Porphyrin Derivative Combined With Pulsed Low-Intensity Ultrasound on PC-9 Cells

Sonodynamic therapy (SDT) is a developing modality for cancer treatment based on the synergistic effect of ultrasound and chemical compounds which are known as sonosensitizers. The development of more efficient sonosensitizers has become an urgent issue in this field. In this study, a novel porphyrin derivative (BBTPP) mediated SDT was evaluated on PC-9 cells. Pulsed low-intensity ultrasound (PLIU) was used for its little thermal and mechanical damage. The accumulation of drugs in cells was evaluated through porphyrin fluorescence, and the cytotoxicity of BBTPP was evaluated using a cell counting kit-8 assay. The sonodynamic effect was investigated by Hoechst 33342/PI and Annexin V-FITC/PI double staining, which showed an apoptotic rate of 18.87% in the BBTPP-SDT group, as compared with 1.71%, 1.4%, 1.57%, 3.61%, 11.18% in the control, BBTPP, hematoporphyrin monomethyl ether (HMME), ultrasound, and HMME-SDT groups, respectively. The sono-toxic effect of BBTPP was significantly superior to HMME. Our results showed that BBTPP-SDT resulted in much higher intracellular reactive oxygen species (ROS) and lipid peroxidation levels which were evaluated by 2′,7′-dichlorodihydrofluorescein diacetate (H₂DCFDA) and Liperfluo assay, respectively. The expressions of Bax, Bcl-2, caspase-9, caspase-8, and cleaved caspase-3 proteins were evaluated to investigate the apoptotic mechanism of BBTPP-SDT. The results of this study showed that the combination of BBTPP and PLIU induced the generation of ROS, resulting in lipid peroxidation, and activated both the extrinsic and intrinsic apoptotic pathways of PC-9 cells. Our results also suggested that the ether group introduced in the side chain of porphyrin could enhance the sono-toxicity of porphyrin-based sensitizers under the sonication of PLIU. These results supported the possibility of BBTPP as a promising sonosensitizer, and an appropriate side chain could enhance the sono-sensitivity of porphyrins.

Concise Nanoplatform of Phycocyanin Nanoparticle Loaded with Docetaxel for Synergetic Chemo-sonodynamic Antitumor Therapy

Combined chemotherapy and sonodynamic therapy (chemo-SDT) based on the nanoplatform/nanocarrier is a potential antitumor strategy that has shown higher therapeutic efficacy than any monotherapy. Therefore, a safe and effective multifunctional system with a concise design and simple preparation process is urgently needed. In this work, by using a one-step cross-linking method, a multifunctional nanosystem, which employs phycocyanin nanoparticles (PCNPs) as a nanocarrier to deliver the chemotherapy drug docetaxel (DTX) and a nanosonosensitizer to generate reactive oxygen species (ROS), was prepared and evaluated (PCNP-DTX). Under low-intensity ultrasound irradiation, PCNP-DTX retained the ROS generation ability of phycocyanin and caused the destruction of mitochondrial potential. PCNP was also revealed to be an acidic and ultrasound-sensitive carrier with good biocompatibility. In addition to its cumulation behavior in tumors, PCNP can achieve tumor-targeted delivery and release of DTX. PCNP-DTX has also been proven to have a significant chemo-SDT synergy effect when low-intensity ultrasound was applied, showing enhanced antitumor activity both in vitro and in vivo. This study provides a concise yet promising nanoplatform based on the natural protein phycocyanin for achieving an effective, targeted, and synergetic chemo-SDT for antitumor therapy.

Multifunctional nanozyme for multimodal imaging-guided enhanced sonodynamic therapy by regulating the tumor microenvironment

Sonodynamic therapy (SDT) is a highly promising approach for cancer therapy, but its efficacy is severely hampered by the low specificity of sonosensitizers and the unfavorable characteristics of the tumor microenvironment (TME), such as hypoxia and glutathione (GSH) overexpression. To solve these problems, in this work, we encapsulated IR780 and MnO₂ in PLGA and linked Angiopep-2 (Ang) to synthesize a multifunctional nanozyme (Ang-IR780-MnO₂-PLGA, AIMP) to enhance SDT. With Ang functionalization to facilitate blood-brain barrier (BBB) penetration and glioma targeting, and through the function of IR780, these nanoparticles (NPs) showed improved targeting of cancer cells, especially mitochondria, and spread deep into tumor centers. Upon low-intensity focused ultrasound (LIFU) irradiation, reactive oxygen species (ROS) were produced and induced tumor cell apoptosis. Combined with the specific mitochondria-targeting ability of IR780, the sonodynamic effects were amplified because mitochondria are sensitive to ROS. In addition, MnO₂ exhibited enzyme-like activity, reacting with the high levels of hydrogen protons (H⁺), H₂O₂ and GSH in the TME to continuously produce oxygen and consume GSH, which further enhanced the effect of SDT. Moreover, Mn²⁺ can be released in response to TME stimulation and used as a magnetic resonance (MR) contrast agent. In addition, IR780 has photoacoustic (PA)/fluorescence (FL) imaging capabilities. Our results demonstrated that AIMP NPs subjected to LIFU triggering maximally enhanced the therapeutic effect of SDT by multiple mechanisms, including multiple targeting, deep penetration, oxygen supply in situ and GSH depletion, thereby significantly inhibiting tumor growth and distal metastasis without systemic toxicity. In summary, this multifunctional nanozyme provides a promising strategy for cancer diagnosis and treatment under the intelligent guidance of multimodal imaging (PA/FL/MR) and may be a safe clinical translational method.

Sonodynamic Treatment Induces Selective Killing of Cancer Cells in an In Vitro Co-Culture Model

Sonodynamic Therapy (SDT) is a new anticancer strategy based on ultrasound (US) technique and is derived from photodynamic therapy (PDT); SDT is still, however, far from clinical application. In order to move this therapy forward from bench to bedside, investigations have been focused on treatment selectivity between cancer cells and normal cells. As a result, the effects of the porphyrin activation by SDT on cancer (HT-29) and normal (HDF 106-05) cells were studied in a co-culture evaluating cell cytotoxicity, reactive oxygen species (ROS) production, mitochondrial function and plasma membrane fluidity according to the bilayer sonophore (BLS) theory. While PDT induced similar effects on both HT-29 and HDF 106-05 cells in co-culture, SDT elicited significant cytotoxicity, ROS production and mitochondrial impairment on HT-29 cells only, whereas HDF 106-05 cells were unaffected. Notably, HT-29 and HDF 106-05 showed different cell membrane fluidity during US exposure. In conclusion, our data demonstrate a marked difference between cancer cells and normal cells in co-culture in term of responsiveness to SDT, suggesting that this different behavior can be ascribed to diversity in plasma membrane properties, such as membrane fluidity, according to the BLS theory.

Single-cell RNA sequencing reveals the mechanism of sonodynamic therapy combined with a RAS inhibitor in the setting of hepatocellular carcinoma

BACKGROUND

Ras activation is a frequent event in hepatocellular carcinoma (HCC). Combining a RAS inhibitor with traditional clinical therapeutics might be hampered by a variety of side effects, thus hindering further clinical translation. Herein, we report on integrating an IR820 nanocapsule-augmented sonodynamic therapy (SDT) with the RAS inhibitor farnesyl-thiosalicylic acid (FTS). Using cellular and tumor models, we demonstrate that combined nanocapsule-augmented SDT with FTS induces an anti-tumor effect, which not only inhibits tumor progression, and enables fluorescence imaging. To dissect the mechanism of a combined tumoricidal therapeutic strategy, we investigated the scRNA-seq transcriptional profiles of an HCC xenograft following treatment.

RESULTS

Integrative single-cell analysis identified several clusters that defined many corresponding differentially expressed genes, which provided a global view of cellular heterogeneity in HCC after combined SDT/FTS treatment. We conclude that the combination treatment suppressed HCC, and did so by inhibiting endothelial cells and a modulated immunity. Moreover, hepatic stellate secretes hepatocyte growth factor, which plays a key role in treating SDT combined FTS. By contrast, enrichment analysis estimated the functional roles of differentially expressed genes. The Gene Ontology terms "cadherin binding" and "cell adhesion molecule binding" and KEGG pathway "pathway in cancer" were significantly enriched by differentially expressed genes after combined SDT/FTS therapy.

CONCLUSIONS

Thus, some undefined mechanisms were revealed by scRNA-seq analysis. This report provides a novel proof-of-concept for combinatorial HCC-targeted therapeutics that is based on a non-invasive anti-tumor therapeutic strategy and a RAS inhibitor.

Modulation of the triggered apoptosis by nano emodin transfersome-mediated sonodynamic therapy on head and neck squamous cell carcinoma cell lines

BACKGROUND

Non-invasive sonodynamic therapy (SDT) is a new treatment modality that uses low-intensity ultrasound to activate a non-toxic sensitizing chemical agent for cancer therapy in a site-directed manner. This study aimed to investigate the anti-cancer effects of ultrasound combined with nano emodin transfersome (NET) on head and neck squamous cell carcinoma (HNSCC) cell lines.

MATERIALS AND METHODS

A transfersome form of nano emodin as a novel sono-responsive nanomaterial was synthesized to enhance the accumulation and penetration of nanoparticles. iIn vitro experiments including hemolytic activity, cell proliferation, intracellular reactive oxygen species (ROS) generation, apoptosis induction, DNA fragmentation, and mRNA expressions of caspase 3 and 9 were conducted to explore the anti-cancer effects of NET-SDT on FaDu and CAL-27 cell lines.

RESULTS

Characterization tests showed the round and uniform morphology of NET with transfersome structure, resulting in a high drug-loading content and encapsulation efficiency. No significant hemolytic activity was observed (P > 0.05). Cytotoxicity gradually increased with increasing concentrations of NET, so that 10 × 10^-4 g/L of NET plus 5 min ultrasound irradiation at a frequency of 1 MHz and ultrasonic intensity of 2 W/cm² effectively killed 98.2 % and 97.3 % of FaDu and CAL-27 cell lines, respectively (P < 0.05). We found that ROS generation in NET-SDT was dose-dependent and the triggered apoptosis and caspase-3/9 gene expression levels were significantly enhanced as the concentration of NET increased (P < 0.05). No significant difference was found in the rate of apoptosis induction and gene expression between two cell lines.

CONCLUSIONS

Our data demonstrated that SDT with NET as a sonosensitizer can induce apoptosis and significantly decrease cell viability of HNSCC cell lines, which represents the role of NET-SDT as a potent anti-cancer modality.

Plasma Membrane Blebbing Dynamics Involved in the Reversibly Perforated Cell by Ultrasound-Driven Microbubbles

The perforation of plasma membrane by ultrasound-driven microbubbles (i.e., sonoporation) provides a temporary window for transporting macromolecules into the cytoplasm that is promising with respect to drug delivery and gene therapy. To improve the efficacy of delivery while ensuring biosafety, membrane resealing and cell recovery are required to help sonoporated cells defy membrane injury and regain their normal function. Blebs are found to accompany the recovery of sonoporated cells. However, the spatiotemporal characteristics of blebs and the underlying mechanisms remain unclear. With a customized platform for ultrasound exposure and 2-D/3-D live single-cell imaging, localized membrane perforation was induced with ultrasound-driven microbubbles, and the cellular responses were monitored using multiple fluorescent probes. The results indicated that localized blebs undergoing four phases (nucleation, expansion, pausing and retraction) on a time scale of tens of seconds to minutes were specifically involved in the reversibly sonoporated cells. The blebs spatially correlated with the membrane perforation site and temporally lagged (about tens of seconds to minutes) the resealing of perforated membrane. Their diameter (about several microns) and lifetime (about tens of seconds to minutes) positively correlated with the degree of sonoporation. Further studies revealed that intracellular calcium transients might be an upstream signal for triggering blebbing nucleation; exocytotic lysosomes not only contributed to resealing of the perforated membrane, but also to the increasing bleb volume during expansion; and actin components accumulation facilitated bleb retraction. These results provide new insight into the short-term strategies that the sonoporated cell employs to recover on membrane perforation and to remodel membrane structure and a biophysical foundation for sonoporation-based therapy.

Early modulation of macrophage ROS-PPARγ-NF-κB signalling by sonodynamic therapy attenuates neointimal hyperplasia in rabbits

Disruption of re-endothelialization and haemodynamic balance remains a critical side effect of drug-eluting stents (DES) for preventing intimal hyperplasia. Previously, we found that 5-aminolevulinic acid-mediated sonodynamic therapy (ALA-SDT) suppressed macrophage-mediated inflammation in atherosclerotic plaques. However, the effects on intimal hyperplasia and re-endothelialization remain unknown. In this study, 56 rabbits were randomly assigned to control, ultrasound, ALA and ALA-SDT groups, and each group was divided into two subgroups (n = 7) on day 3 after right femoral artery balloon denudation combined with a hypercholesterolemic diet. Histopathological analysis revealed that ALA-SDT enhanced macrophage apoptosis and ameliorated inflammation from day 1. ALA-SDT inhibited neointima formation without affecting re-endothelialization, increased blood perfusion, decreased the content of macrophages, proliferating smooth muscle cells (SMCs) and collagen but increased elastin by day 28. In vitro, ALA-SDT induced macrophage apoptosis and reduced TNF-α, IL-6 and IL-1β via the ROS-PPARγ-NF-κB signalling pathway, which indirectly inhibited human umbilical artery smooth muscle cell (HUASMC) proliferation, migration and IL-6 production. ALA-SDT effectively inhibits intimal hyperplasia without affecting re-endothelialization. Hence, its clinical application combined with bare-metal stent (BMS) implantation presents a potential strategy to decrease bleeding risk caused by prolonged dual-antiplatelet regimen after DES deployment.

Applications of inorganic nanoparticles in the diagnosis and therapy of atherosclerosis

Atherosclerosis is a chronic progressive disease, which may result in serious clinical outcomes, such as acute heart events or stroke with high mortality. At present, the clinical problems of atherosclerosis mainly consist of the difficulty in confirming the plaques or identifying the stability of the plaques in the early phase and the shortage of valid treatments. Fortunately, with the development of nanotechnology, various inorganic nanoparticles with imaging enhancement and noninvasive therapy functions have been studied in the imaging and treatment of atherosclerosis, which has brought new hope to patients. This review focuses on the recent progress in the use of inorganic nanoparticles in the diagnosis and therapy of atherosclerosis, including the key processes in the development of atherosclerosis and the mainly involved cells, inorganic nanoparticle-based dual-mode imaging methods classified by the types of targeting cells, and inorganic nanoparticle-based therapeutic approaches, such as photothermal therapy (PTT), photodynamic therapy (PDT), sonodynamic therapy (SDT), drug delivery, gene therapy and imaging-guided therapy for atherosclerosis. Finally, this review discusses the challenges and directions of inorganic nanoparticles in potential clinical translation of anti-atherosclerosis in future. We believe this review will enable readers to systematically understand the progress of the inorganic nanoparticle-based imaging and therapy of atherosclerosis and therefore promote the further development of anti-atherosclerosis.

Hematoporphyrin monomethyl ether-mediated sonodynamic therapy induces A-253 cell apoptosis

It has been found that >90% of oral cancer patients suffer from squamous cell carcinoma (SCC). The 5-year survival rate of SCC is ~50%, despite the availability of different treatments. Sonodynamic therapy (SDT) has been developed as a novel therapy for cancer, resisting bacterial infection and inhibiting atherosclerotic plaque progression. The present study investigated the efficacy of hematoporphyrin monomethyl ether (HMME)-mediated SDT on the A-253 epidermoid cancer cell line. The cytotoxicity of HMME and the survival rate of cells following SDT were examined by the MTT assay. Apoptosis and necrosis of cells were detected using flow cytometry with Annexin V and propidium iodide (PI) staining, and fluorescence microscopy with Hoechst 33258 and PI staining. Intracellular reactive oxygen species (ROS) and Ca²⁺ levels were measured using a fluorescence microscope based on 2′,7′-dichlorofluorescein diacetate and fluo-3/acetoxymethylester, respectively. Results of the MTT assay demonstrated that a lower concentration (<10 µg/ml) of HMME had no significant effect on the A-253 cells, but SDT combined with ultrasonic treatment for 1 min and 10 µg/ml HMME decreased the cell survival rate by 27%. Flow cytometry analysis revealed that A-253 cells in the SDT group had a higher rate of late apoptosis compared with the control group. Furthermore, fluorescence quantitation of apoptotic A-253 cells demonstrated that the percentages of apoptotic cells were increased in the ultrasound and SDT group compared with those in the control group. In the present study, the ROS level in the SDT group was elevated compared with that in the control group. The Ca²⁺ levels were increased to 181.2 and 268.7% in the ultrasound and SDT groups, respectively, relative to the control group. Taken together, the findings of the present study demonstrated that HMME-SDT significantly induces the apoptosis of A-253 cells together with intracellular ROS generation and Ca²⁺ overload. Thus, HMME-SDT may be a promising treatment option for patients with SCC.

Sonomagnetic Stimulation of Live Cells: Electrophysiologic, Biochemical and Behavioral Responses

Various physical methods have been developed to modulate the electrophysiologic properties of cells and their biochemical signaling pathways. In this study, we propose a sonomagnetic method using pulsed ultrasound (1.1 MHz frequency, 1.1 or 2.2 MPa pressure, 50 cycles per pulse and 500 Hz pulse repetition frequency) and a static magnetic field (680 mT) to stimulate live cells. We found that sonomagnetic stimulation promoted the cell and mitochondrial membrane potentials to more hyperpolarized states. The degree of cell membrane hyperpolarization was cell-type dependent. Furthermore, we found that the intracellular concentrations of Ca²⁺ ions, reactive oxygen species and nitric oxide were substantially increased after sonomagnetic stimulation, and a small decrease in intracellular pH was also observed. Lastly, we found that the daily sonomagnetic stimulation for 3 d inhibited the proliferation rate of neuro-2a cancer cells by 48.64%. Our work demonstrates that sonomagnetic stimulation can effectively perturb cell signaling and drive cancer cells into relatively quiescent states.

Membrane-permeabilized sonodynamic therapy enhances drug delivery into macrophages

Macrophages play a pivotal role in the formation and development of atherosclerosis as a predominant inflammatory cell type present within atherosclerotic plaque. Promoting anti-atherosclerotic drug delivery into macrophages may provide a therapeutic potential on atherosclerotic plaque. In this study, we investigated whether membrane-permeabilized sonodynamic therapy (MP-SDT) enhances drug delivery into THP-1 macrophages. Images of confocal microscopy confirmed that the optimal plasma distribution of the sonosensitizer protoporphyrin IX (PpIX) was at 1 hour incubation. The non-lethal parameter of MP-SDT was determined by cell viability as measured by a CCK-8 assay. Bright field microscopy demonstrated plasma membrane deformation in response to MP-SDT. Using SYTOX Green, a model drug for cellular uptake, we found that MP-SDT significantly induced membrane permeabilization dependent on ultrasound intensity and exposure time. Using Fluo-3 AM, intracellular calcium elevation during MP-SDT was confirmed as a result of membrane permeabilization. Membrane perforation of MP-SDT-treated cells was observed by scanning electron microscopy and transmission electron microscopy. Moreover, MP-SDT-induced membrane permeabilization and perforation were remarkably prevented by scavenging reactive oxygen species (ROS) during MP-SDT. Furthermore, we assessed the therapeutic effect of MP-SDT in combination with anti-atherosclerotic drug atorvastatin. Our results showed that MP-SDT increased the therapeutic effect of atorvastatin on lipid-laden THP-1-derived foam cells, including decreasing lipid droplets, increasing the cholesterol efflux and the expression of PPARγ and ABCG1. In conclusion, MP-SDT might become a promising approach to facilitating the delivery of anti-atherosclerotic drugs into macrophages via membrane permeabilization.

Mitochondria-Targeted and Ultrasound-Activated Nanodroplets for Enhanced Deep-Penetration Sonodynamic Cancer Therapy

Sonodynamic therapy (SDT), a promising alternative for cancer therapy, utilizes a sonosensitizer combined with ultrasound (US) irradiation to damage tumor cells/tissues for therapeutic purposes. The ability of sonosensitizers to specifically accumulate in tumor cells/tissues could greatly influence their therapeutic efficiency. In this work, we report the use of US-activated sonosensitizer (IR780)-based nanodroplets (IR780-NDs) for SDT, which provide numerous benefits for killing cancer cells compared with traditional methods. For instance, IR780-NDs showed effective surface-to-core diffusion both in vitro and in vivo. In the presence of US, the acoustic droplet vaporization (ADV) effect significantly assisted the conveyance of IR780-NDs from the circulatory system to tumor regions, and the acoustic wave force also increased the penetration depth within tumor tissues. Furthermore, IR780-NDs possesses mitochondrial targeting capabilities, which improves the precision and accuracy of SDT delivery. During the in vitro assessment, the overproduction of reactive oxygen species (ROS) was observed following mitochondrial targeting, which rendered cancer cells more susceptible to ROS-induced apoptosis. Additionally, IR780-ND is a suitable candidate for photoacoustic and fluorescence imaging and can also enhance US imaging because of the ADV-generated bubbles, which provides the potential for SDT guidance and monitoring. Therefore, with combined modalities, IR780-NDs can be a promising theranostics nanoplatform for cancer therapy.

An acoustic strategy for gold nanoparticle loading in platelets as biomimetic multifunctional carriers

In recent years, a wide variety of bioinspired colloidal particles with novel cell mimetic functions have been the subject of extensive research in materials science, chemistry, biology, physics, and engineering. However, most of the approaches are derived from natural cell membrane coatings, which are still too primitive compared with living cells. In this study, we have chosen gold nanoparticles (GNPs) to explore the bioactivity response of living platelets and nanoparticle loading efficiency under different ultrasonic intensity and frequency treatment conditions. The results show that GNPs with no surface modification could be easily loaded into intra-platelets by both incubation (30 min) and ultrasonic exposure (1 min) methods. The amount of GNP loading was (4.4 ± 0.9) × 10^-3 and (5.8 ± 2.4) × 10^-3 pg per platelet upon incubation and acoustic triggering (1 MHz, 0.25 W cm^-2), respectively. Although the other US treatment intensities (0.75, 1.50 and 2.25 W cm^-2) also promoted higher amounts of GNPs in the platelets, the higher US intensity might bring about partial damage of the platelet membrane. Compared with 1 MHz ultrasonic exposure, the change of the GNP loading amount was not significantly higher upon ultrasonic frequency treatment of 45, 80 or 100 kHz. Therefore, it has been found that an US intensity of 0.25 W cm^-2 could facilitate the intra-platelet delivery efficacy of the GNPs without damaging the biological activity. Furthermore, two possible pathways of GNPs entering into platelets upon US treatment are presented: one is the endocytosis/open canalicular system (OCS), and the other is cell membrane permeability enhancement, which is proved by the SEM and TEM results. Finally, the GNP-loaded platelets have been demonstrated as useful probes for photoacoustic imaging (PAI) and dark-field microscopy (DFM)-based imaging, which might allow a wide range of potential applications in diagnostics and therapy of platelet-related diseases.

Genomic insult oriented mitochondrial instability and proliferative hindrance in the bone marrow of aplastic mice including stem/progenitor population

Aplastic anemia is the bone marrow failure condition characterized by the development of hypocellularity in both marrow and peripheral blood compartments. Anti-tumor chemotherapeutic agents often exert secondary effect on hematopoietic system leading to aplastic anemia by marrow failure. The precise mechanisms behind the marrow ablative effects of the drugs remain yet to be established. The present study holds a mechanistic approach to unveil the mystery. Aplastic anemia was generated in mice with the administration of busulfan and cyclophosphamide followed by the characterization of the disease with peripheral blood hemogram, histopathological and cytochemical examinations of bone marrow. To gain deep knowledge about the molecular mechanisms of the hematopoietic disruption, cytotoxicity assay, DNA damage measurement, apoptosis study, replicative senescence analysis, redox balance study, mitochondrial membrane potential change assessment, flowcytometric expressional analysis of p21, p53, ATM, Chk-2, Necdin, Gfi-1, c-myc, KU-80 and Sod-2 were done with marrow hematopoietic stem/ progenitor cells (HSPCs). Severe blood pancytopenia and marrow hypocellularity was found in aplastic mice. Proliferative hindrance and apoptosis of marrow cells were identified as the cause behind the hematopoietic catastrophe. The genotoxic effects of the drugs triggered chromatin damage and induced replicative senescence in aplastic HSPCs by upregulating p21 in a p53 independent manner. Moreover, accumulation of genomic insults also caused apoptotic elimination of marrow cells due to disruption of mitochondrial membrane potential by generating redox imbalance. The study established the underlying mechanisms behind hematopoietic disruption during drug induced marrow aplasia. Outcome of the study may be helpful in successful designing of therapeutic strategies for the disease concerned.

Sonodynamic therapy: A potential treatment for atherosclerosis

Atherosclerosis (AS), a chronic arterial disease, is one of the major causes of morbidity and mortality worldwide. Several treatment modalities have been demonstrated to be effective in treating AS; however, the mortality rate due to AS remains high. Sonodynamic therapy (SDT) is a promising new treatment using low-intensity ultrasound in combination with sonosensitizers. Although SDT was developed from photodynamic therapy (PDT), it has a stronger tissue-penetrating capability and exhibits a more focused effect on the target lesional site requiring treatment. Furthermore, SDT has been demonstrated to suppress the formation of atheromatous plaques, and it can increase plaque stability both in vitro and in vivo. In this article, we critically summarize the recent literature on SDT, focusing on its possible mechanism of action as well as the existing and newly discovered sonosensitizers and chemotherapeutic agents for the treatment of AS.

Nanoparticle-assisted ultrasound: A special focus on sonodynamic therapy against cancer

At present, ultrasound radiation is broadly employed in medicine for both diagnostic and therapeutic purposes at various frequencies and intensities. In this review article, we focus on therapeutically-active nanoparticles (NPs) when stimulated by ultrasound. We first introduce the different ultrasound-based therapies with special attention to the techniques involved in the oncological field, then we summarize the different NPs used, ranging from soft materials, like liposomes or micro/nano-bubbles, to metal and metal oxide NPs. We therefore focus on the sonodynamic therapy and on the possible working mechanisms under debate of NPs-assisted sonodynamic treatments. We support the idea that various, complex and synergistics physical-chemical processes take place during acoustic cavitation and NP activation. Different mechanisms are therefore responsible for the final cancer cell death and strongly depends not only on the type and structure of NPs or nanocarriers, but also on the way they interact with the ultrasonic pressure waves. We conclude with a brief overview of the clinical applications of the various ultrasound therapies and the related use of NPs-assisted ultrasound in clinics, showing that this very innovative and promising approach is however still at its infancy in the clinical cancer treatment.

Generation of Reactive Oxygen Species in Heterogeneously Sonoporated Cells by Microbubbles with Single-Pulse Ultrasound

To develop and realize sonoporation-based macromolecule delivery, it is important to understand the underlying cellular bioeffects involved. It is known that an appropriate level of reactive oxygen species (ROS) is necessary to maintain normal physiologic function, but excessive ROS triggers adverse downstream bioeffects. However, it is still unclear whether a relationship exists between intracellular ROS levels and sonoporation. Using a customized platform for 1.5-MHz ultrasound exposure (13.33 µs duration and 0.70 MPa peak negative pressure) and imaging the dynamics of sonoporation and intracellular ROS at the single-cell level, we quantified the exogenous molecular uptake and the concentration of intracellular ROS indicator to evaluate the extent of sonoporation and ROS change, respectively. Our results revealed that the intracellular ROS level was correlated with the degree of the sonoporation. (i) Within ~120 s of the onset of ultrasound, during which membrane perforation and complete membrane resealing occurred, intracellular ROS rapidly decreased because of extracellular diffusion of dichlorofluorescein through the perforated membrane and positively correlated with the degree of the sonoporation. (ii) In the following 270 s (120-390 s post-exposure), ROS generation in reversibly sonoporated cells gradually increased and was positively correlated with the degree of the sonoporation. (iii) The ROS level in irreversibly sonoporated cells reduced to depletion during this time interval. It is possible that ROS generation in reversibly sonoporated cells can impact their long-term fate. These results thus provide new insight into the biological response to sonoporation.

An investigation of the mechanism of dexmedetomidine in improving postoperative cognitive dysfunction from the perspectives of alleviating neuronal mitochondrial membrane oxidative stress and electrophysiological dysfunction

The aim of this study was to investigate the mechanism of dexmedetomidine in improving postoperative cognitive dysfunction from the perspectives of alleviating neuronal mitochondrial membrane oxidative stress and electrophysiological dysfunction. A total of 120 patients undergoing elective surgery under general anesthesia from June 2013 to May, 2016 were selected as the subjects of the study and randomly divided into the propofol + remifentanil and dexmedetomidine groups. The Rey Auditory Verbal Learning Test (AVLT) and Beck Depression Inventory (BDI) were performed at day 1 before operation and at day 1, 3, 5 and 15 after operation. The mitochondrial membrane potential was detected using a flow cytometer after staining and labeling for mitochondria in leukocytes via JC-1 fluorescence staining using a fluorescence probe at day 1 before operation and at day 1, 3, 5 and 15 after operation. The activities of mitochondrial respiratory chain complexes at day 1 before and after operation were detected via enzyme-linked immunosorbent assay (ELISA). The results showed that there were no statistically significant differences in the comparisons of general conditions (age, body weight, sex ratio, body mass index, anesthesia time, operation time, and length of stay in the ICU and hospital) for the dexmedetomidine and propofol + remifentanil groups (P>0.05). At day 3 and 5 after operation, the National Institutes of Health Stroke Scale (NIHSS) scores and AVLT scores in the two groups were decreased in different degrees, but the decrease range in the dexmedetomidine group was smaller than that in the propofol + remifentanil group, and the differences were statistically significant (P<0.05). At day 3, 5 and 15 after operation, the BDI scores of the two groups were increased in different degrees, but the increase range in the dexmedetomidine group was smaller than that in the propofol + remifentanil group, and the differences were statistically significant (P<0.05). At day 1, 3 and 5 after operation, the mitochondrial membrane potentials of the two groups were decreased in different degrees, but the decrease range in the dexmedetomidine group was smaller than that in the propofol + remifentanil group, and the differences were statistically significant (P<0.05). The mitochondrial membrane potentials of the two groups returned to the preoperative levels at day 15 after operation. The activities of mitochondrial respiratory chain complex I–IV in the propofol + remifentanil group at day 1 after operation were significantly decreased compared with those before operation, and the differences were statistically significant (P<0.05). The decrease in activities of mitochondrial respiratory chain complex I–IV in the propofol + remifentanil group at day 1 after operation was more significant than that in the dexmedetomidine group, and the difference was statistically significant (P<0.05). The results suggest that dexmedetomidine can relieve neuronal damage that may be caused by mitochondrial membrane oxidative stress, alleviate the damage to mitochondrial related enzyme system activity, and reduce the damage to the activities of mitochondrial respiratory chain enzyme complex I, II, III and IV, ultimately improving the postoperative cognitive dysfunction of patients.

TAT‑fused IP3R‑derived peptide enhances cisplatin sensitivity of ovarian cancer cells by increasing ER Ca2+ release

Ovarian cancer is the most common gynecological malignancy. At present, cisplatin is used to treat ovarian cancer; however, the development of cisplatin resistance during therapy is a common obstacle to achieving favorable outcomes. Recently, the B‑cell lymphoma 2 (Bcl‑2) BH4 domain has been reported to mediate the prosurvival activity of Bcl‑2 in cancer; however, the involvement of the BH4 domain of Bcl‑2 in the cisplatin resistance of ovarian carcinoma cells is not entirely clear. In this study, we observed the cytoplasmic and mitochondrial levels of Ca2+ by confocal laser microscopy. We also detected cell apoptosis using western blot analysis and flow cytometry. The present study demonstrated that TAT‑fused inositol 1,4,5‑trisphosphate receptor‑derived peptide (TAT‑IDPS), which targets the BH4 domain of Bcl‑2, increased cisplatin‑induced Ca2+ flux from the endoplasmic reticulum (ER) into the cytosol and mitochondria. In addition, TAT‑IDPS increased cisplatin‑induced expression of mitochondrial apoptosis‑associated proteins and ER stress‑associated proteins. These results indicated that TAT‑IDPS may enhance the cytotoxicity of cisplatin toward ovarian carcinoma cells by increasing ER Ca2+ release.

Efficacy of Indocyanine Green-Mediated Sonodynamic Therapy on Rheumatoid Arthritis Fibroblast-like Synoviocytes

Sonodynamic therapy (SDT) has become a new therapeutic method because of its activation of certain sensitizers by ultrasound. Some studies have reported that indocyanine green (ICG) has the characteristics of a sonosensitizer and favorable fluorescence imaging in synovitis of early inflammatory arthritis. In this study, we aimed to investigate the cytotoxic effect of ICG-mediated SDT on MH7A cells in vitro and the potential mechanisms involved. ICG was found to be taken up mainly in cytoplasm, with maximal uptake in 4 h. Cell viability in ICG-mediated SDT (SDT-0.5 and SDT-1.0) groups decreased significantly to 73.09 ± 1.97% and 54.24 ± 4.66%, respectively; cell apoptosis increased significantly to 26.43 ± 0.91% and 45.93 ± 6.17%, respectively. Moreover, marked loss in mitochondrial membrane potential and greatly increased generation of reactive oxygen species were observed in ICG-mediated SDT groups. Interestingly, the loss in cell viability could be effectively rescued with pretreatment with the reactive oxygen species scavenger N-acetylcysteine. These results indicate that ICG-mediated SDT is cytotoxic to fibroblast-like synoviocytes and is a potential modality for targeted therapy of synovitis in rheumatoid arthritis.

Protoporphyrin IX-mediated sonodynamic therapy promotes autophagy in vascular smooth muscle cells

Sonodynamic therapy (SDT) is effective in treating intimal hyperplasia and promoting plaque stability in animal models. The present study aimed to evaluate the effects of SDT with the sonosensitizer protoporphyrin IX (PpIX) on vascular smooth muscle cell (VSMC) viability and autophagy. Cultured VSMCs cells were divided into the following groups: i) Control, ii) ultrasound, iii) PpIX and iv) SDT. Flow cytometry and laser confocal detection were used to measure Annexin V stained VSMCs following different treatments. Alterations in mitochondrial membrane potential (MMP) were evaluated via JC-1 staining. Autophagosome formation was observed using electron and fluorescence microscopy. Western blotting was used to analyze the expression levels of the autophagy markers light chain 3 (LC3-I) and LC3-II. The results demonstrated that SDT did not trigger apoptosis nor induce a significant decline in MMP of VSMCs. However, SDT significantly increased autophagasome formation and increased the LC3-II/LC3-I ratio. The findings demonstrated that PpIX-SDT increased autophagy without inducing mitochondrial-dependent apoptosis in VSMCs.

Sonodynamic therapy, a treatment developing from photodynamic therapy

Sonodynamic therapy (SDT) as a new non-invasive treatment developed from photodynamic (PDT), it can kill tumor cells specifically and selectively. Moreover, recently studies showed SDT has potential to treat solid tumor, leukemia and atherosclerosis, remove proliferative scars and kill pathogenic microorganism. As SDT has an extensive application prospect, SDT has attracted more and more research recently. This thesis aims to be an informative introduction on SDT. With the assistance of related literature from 2012 to 2016, we introduce the progress of SDT research in six aspects: the therapeutic mechanism of SDT, development of the sound sensitizer, exploration of the size and frequency of ultrasonic energy, application of SDT, comparison between SDT and PDT, and current situation and future of SDT.

Oxygen and indocyanine green loaded phase-transition nanoparticle-mediated photo-sonodynamic cytotoxic effects on rheumatoid arthritis fibroblast-like synoviocytes

BACKGROUND

Photodynamic therapy and sonodynamic therapy are developing, minimally invasive, and site-specific modalities for cancer therapy. A combined strategy PSDT (photodynamic therapy followed by sonodynamic therapy) has been proposed in this study. Here, we aimed to develop novel biodegradable poly(DL-lactide-co-glycolic acid) phase-transition nanoparticles simultaneously loaded with oxygen and indocyanine green (OI-NPs) and to investigate the cytotoxic effects and the potential mechanisms of OI-NP-mediated PSDT on MH7A synoviocytes.

METHODS

The OI-NPs were prepared using a modified double emulsion method and the physicochemical properties were determined. The cellular uptake of OI-NPs was detected by confocal microscopy and flow cytometry. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide assay, flow cytometry, and Hoechst 33342/propidium iodide double staining were used to determine the cytotoxic effect of OI-NP-mediated PSDT on MH7A cells. Fluorescence microscope and fluorescence microplate reader were used to detect reactive oxygen species (ROS) generation.

RESULTS

The OI-NPs were a stable and efficient carrier to deliver oxygen and indocyanine green, and enhanced cellular uptake was observed in MH7A cells with the nanoparticles. OI-NP-mediated PSDT caused more serious cell damage and more evident cell apoptosis, compared with other groups. Furthermore, increased generation of intracellular ROS was detected in MH7A cells treated with PSDT. Interestingly, the OI-NP-mediated PSDT-induced cell viability loss was effectively rescued by pretreatment with the ROS scavenger N-acetylcysteine.

CONCLUSION

Multifunctional OI-NPs were successfully developed and characterized for the combined delivery of oxygen and indocyanine green, and OI-NP-mediated PSDT would be a potential cytotoxic treatment for MH7A cells. This study may provide a novel strategy for the treatment of RA and develop a model of theranostic application through phase-transition nanoparticle-mediated PSDT in the future.

IR-780 Dye as a Sonosensitizer for Sonodynamic Therapy of Breast Tumor

Sonodynamic therapy (SDT) has become a new modality for cancer therapy through activating certain chemical sensitizers by ultrasound (US). Discovery and development of novel sonosensitizers are attracting extensive attentions. Here, we introduce IR-780 iodide, a lipophilic heptamethine dye with a peak optical absorption of 780 nm wavelength, which can function as SDT agents for breast cancer treatment. The in vitro cellular uptake, cell viability, and the generation levels of reactive oxygen species (ROS) were examined by using 4T1 breast cancer cells incubated with various concentrations of IR-780 followed by US irradiation. Our results showed a dose- and time-dependent cellular uptake of IR-780 iodide in 4T1 cancer cells. Significant lower viabilities and more necrotic/apoptotic cells were found when these cancer cells were treated with IR-780 iodide with US irradiation. Further analyzing the generation of ROS demonstrated significant increase of ¹O₂ level and H₂O₂, but not ⋅OH in the SDT-treated cells. The in vivo anti-tumor efficacy of SDT with IR-780 revealed significant tumor growth inhibition of xenografts of 4T1 cancer cells; it was further confirmed by histological analysis and TUNEL staining. Our results strongly suggest that SDT combined with IR-780 may provide a promising strategy for tumor treatment with minimal side effects.

Recent advances of sonodynamic therapy in cancer treatment

Sonodynamic therapy (SDT) is an emerging approach that involves a combination of low-intensity ultrasound and specialized chemical agents known as sonosensitizers. Ultrasound can penetrate deeply into tissues and can be focused into a small region of a tumor to activate a sonosensitizer which offers the possibility of non-invasively eradicating solid tumors in a site-directed manner. In this article, we critically reviewed the currently accepted mechanisms of sonodynamic action and summarized the classification of sonosensitizers. At the same time, the breath of evidence from SDT-based studies suggests that SDT is promising for cancer treatment.