Evaluation of inertial cavitation activity in tissue through measurement of oxidative stress

A Systematic Review of Traumatic Brain Injury in Modern Rodent Models: Current Status and Future Prospects

According to the Centers for Disease Control and Prevention (CDC), the national public health agency of the United States, traumatic brain injury is among the leading causes of mortality and disability worldwide. The consequences of TBI include diffuse brain atrophy, local post-traumatic atrophy, arachnoiditis, pachymeningitis, meningocerebral cicatrices, cranial nerve lesions, and cranial defects. In 2019, the economic cost of injuries in the USA alone was USD 4.2 trillion, which included USD 327 billion for medical care, USD 69 billion for work loss, and USD 3.8 trillion for the value of statistical life and quality of life losses. More than half of this cost (USD 2.4 trillion) was among working-age adults (25-64 years old). Currently, the development of new diagnostic approaches and the improvement of treatment techniques require further experimental studies focused on modeling TBI of varying severity.

Phthalocyanine-based probes in alleviating or evading tumour-hypoxia for enhanced photo- and/ sono-mediated therapeutic efficacies

This review discusses the possible methods for improving therapeutic efficacies of phthalocyanine (Pcs) -based therapeutic probes in photo- and sono-dynamic therapies under hypoxic conditions. Herein, the structural design strategies including varying the central metal, position substituents and the effects of adjuvant used in supplementing the therapeutics activities of Pcs or formation of NPs are discussed for cancer therapies in hypoxic conditions. Different mechanisms induced for cell death influenced by the compositions of the Pcs-probes are discussed. The focus mainly highlights the oxygen (O2) -dependent mechanisms including methods of supplementing tumour microenvironment O2-concentrations to promote PDT or SDT therapies. Alternatively, O2-independent mechanisms mainly used to evade hypoxia by stimulating anticancer processes that don't require O2 to initiate cell death, such as the Fenton reaction or thermal ablation effects.

Record-High Ultrasound-Sensitive NO Nanogenerators for Cascade Tumor Pyroptosis and Immunotherapy

Pyroptosis is a pro-inflammatory cell death that is associated with innate immunity promotion against tumors. Excess nitric oxide (NO)-triggered nitric stress has potential to induce pyroptosis, but the precise delivery of NO is challenging. Ultrasound (US)-responsive NO production has dominant priority due to its deep penetration, low side effects, noninvasion, and local activation manner. In this work, US-sensitive NO donor N-methyl-N-nitrosoaniline (NMA) with thermodynamically favorable structure is selected and loaded into hyaluronic acid (HA)-modified hollow manganese dioxide nanoparticles (hMnO2 NPs) to fabricate hMnO2 @HA@NMA (MHN) nanogenerators (NGs). The obtained NGs have a record-high NO generation efficiency under US irradiation and can release Mn2+ after targeting the tumor sites. Later on, cascade tumor pyroptosis and cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING)-based immunotherapy is achieved and tumor growth is effectively inhibited.

UTMD inhibit EMT of breast cancer through the ROS/miR-200c/ZEB1 axis

As a potential drug/gene delivery system, the ultrasound-targeted microbubble destruction (UTMD) system can be used as a vehicle as well as increasing the permeability of biological barriers to enhance the effect of tumor treatment. However, the effect of UTMD in the tumor EMT process is unknown. In this study, we aimed to investigate the potential and mechanism of UTMD induced oxidative stress in inhibiting EMT of breast cancer. Human breast MDA231 cells were treated with microbubble (MB), ultrasound (US) and UTMD, respectively. The generation of oxidative stress, the levels of miR-200c, ZEB1 and vimentin, and the numbers of migratory cells were evaluated quantitatively and qualitatively by the measurement of intracellular reactive oxygen species (ROS), qRT-PCR, western blot assay, and transwell assay. Then, to evaluate the role of UTMD-induced oxidative stress and miR-200c in the epithelial-mesenchymal transition (EMT) inhibition, the ROS scavenger N-acetyl-L-cysteine (NAC) and miR-200c inhibitor were used before UTMD treatment. We found that UTMD induced oxidative stress, upregulated the expression of miR-200c, downregulated the expression of ZEB1 and vimentin and suppressed the MDA231 cell migration. The addition of NAC and miR-200c inhibitor had an opposite impact on the expression of miR-200c and ZEB1, thus hindered the effects of UTMD on MDA231 cells EMT. In conclusion, UTMD can inhibit the EMT characteristics of MDA231 cells. The mechanism may be related to the regulation of the miR-200c/ZEB1 axis through the generation of ROS induced by UTMD, which may provide a new strategy to prevent the tumor cells EMT under UTMD treatment.

Ultrasound Mediated Destruction of LMW-HA-Loaded and Folate-Conjugated Nanobubble for TAM Targeting and Reeducation

Purpose

To synthesize and evaluate a novel folate-conjugated ultrasonic nanobubble (HA-FOL-NB) loading low-molecular-weight hyaluronic acid (LMW-HA) for specific tumor-associated macrophages (TAMs) targeting and reeducation.

Methods

The characteristics, cytotoxicity, contrast-enhanced ultrasound imaging (CEUS), and targeting ability to TAMs of HA-FOL-NBs were investigated. The TAMs reprogramming function of HA-FOL-NBs combining ultrasound targeted nanobubble destruction was assessed as well.

Results

HA-FOL-NBs (about 342 nm) showed remarkable contrast enhancement images, and higher targeting ability due to the folate to folate receptor interactions. Combined with ultrasound targeted nanobubble destruction, HA-FOL-NBs could specifically deliver LMW-HA into TAMs, thus exhibited stronger reeducation effect compared with free LMW-HA.

Conclusion

These folate-conjugated and LMW-HA-loaded nanobubbles, with targeted CEUS imaging and TAMs reeducation, are expected to be a potential approach for tumor therapy based on TAMs, especially folate receptor-positive ones.

Cavitation-induced traumatic cerebral contusion and intracerebral hemorrhage in the rat brain by using an off-the-shelf clinical shockwave device

Traumatic cerebral contusion and intracerebral hemorrhages (ICH) commonly result from traumatic brain injury and are associated with high morbidity and mortality rates. Current animal models require craniotomy and provide less control over injury severity. This study proposes a highly reproducible and controllable traumatic contusion and ICH model using non-invasive extracorporeal shockwaves (ESWs). Rat heads were exposed to ESWs generated by an off-the-shelf clinical device plus intravenous injection of microbubbles to enhance the cavitation effect for non-invasive induction of injury. Results indicate that injury severity can be effectively adjusted by using different ESW parameters. Moreover, the location or depth of injury can be purposefully determined by changing the focus of the concave ESW probe. Traumatic contusion and ICH were confirmed by H&E staining. Interestingly, the numbers of TUNEL-positive cells (apoptotic cell death) peaked one day after ESW exposure, while Iba1-positive cells (reactive microglia) and GFAP-positive cells (astrogliosis) respectively peaked seven and fourteen days after exposure. Cytokine assay showed significantly increased expressions of IL-1β, IL-6, and TNF-α. The extent of brain edema was characterized with magnetic resonance imaging. Conclusively, the proposed non-invasive and highly reproducible preclinical model effectively simulates the mechanism of closed head injury and provides focused traumatic contusion and ICH.

Spatially Specific Liposomal Cancer Therapy Triggered by Clinical External Sources of Energy

This review explores the use of energy sources, including ultrasound, magnetic fields, and external beam radiation, to trigger the delivery of drugs from liposomes in a tumor in a spatially-specific manner. Each section explores the mechanism(s) of drug release that can be achieved using liposomes in conjunction with the external trigger. Subsequently, the treatment's formulation factors are discussed, highlighting the parameters of both the therapy and the medical device. Additionally, the pre-clinical and clinical trials of each triggered release method are explored. Lastly, the advantages and disadvantages, as well as the feasibility and future outlook of each triggered release method, are discussed.

Selective sensitiveness of mesenchymal stem cells to shock waves leads to anticancer effect in human cancer cell co-cultures

AIM

Mesenchymal stem cells (MSC) possess the distinctive feature of homing in on and engrafting into the tumor stroma making their therapeutic applications in cancer treatment very promising. Research into new effectors and external stimuli, which can selectively trigger the release of cytotoxic species from MSC toward the cancer cells, significantly raises their potential.

MAIN METHODS

Shock waves (SW) have recently gained recognition for their ability to induce specific biological effects, such as the local generation of cytotoxic reactive oxygen species (ROS) in a non-invasive and tunable manner. We thus investigate whether MSC are able to generate ROS and, in turn, affect cancer cell growth when in co-culture with human glioblastoma (U87) or osteosarcoma (U2OS) cells and exposed to SW.

KEY FINDINGS

MSC were found to be the cell line that was most sensitive to SW treatment as shown by SW-induced ROS production and cytotoxicity. Notably, U87 and U2OS cancer cell growth was unaffected by SW exposure. However, significant decreases in cancer cell growth, 1.8 fold for U87 and 2.3 fold for U2OS, were observed 24h after the SW treatment of MSC co-cultures with cancer cells. The ROS production induced in MSC by SW exposure was then responsible for lipid peroxidation and cell death in U87 and U2OS cells co-cultured with MSC.

SIGNIFICANCE

This experiment highlights the unique ability of MSC to generate ROS upon SW treatment and induce the cell death of co-cultured cancer cells. SW might therefore be proposed as an innovative tool for MSC-mediated cancer treatment.

Enhancement of Fluorescent Probe Penetration into Tumors In Vivo Using Unseeded Inertial Cavitation

Ultrasound-induced cavitation has found many applications in the field of cancer therapy. One of its beneficial effects is the enhancement of drug intake by tumor cells. Our group has developed a device that can create and control unseeded cavitation in tissue using ultrasound. We conducted experiments on tumor-bearing mice using our device to assess the impact of sonication on the penetration of fluorescent probes into tumor cells. We studied the influence of pressure level, timing of sonication and sonication duration on treatment efficiency. Our results indicate that fluorescent probes penetrate better into tumors exposed to ultrasound. The best results revealed an increase in penetration of 61% and were obtained when sonicating the tumor in presence of the probes with a peak negative pressure at focus of 19 MPa. At this pressure level, the treatment generated only minor skin damage. Treatments could be significantly accelerated as equivalent enhanced penetration of probes was achieved when multiplying the initial raster scan speed by a factor of four.