ROS-responsive Nanoparticles Research Articles

ROS Responsive Cerium Oxide Biomimetic Nanoparticles Alleviates Calcium Oxalate Crystals Induced Kidney Injury via Suppressing Oxidative Stress and M1 Macrophage Polarization.

Emerging studies have demonstrated that M1 macrophage polarization and oxidative stress play important roles in calcium oxalate (CaOx) induced kidney injury, which leads to increased crystals deposition. ROS scavenging nanozymes and kidney-targeted nanoparticles for antioxidant drugs delivery have emerged as an arisen methodology for kidney injury therapy. However, cell membrane biomimetic-modified nanozymes as anti-inflammatory drug delivery systems for the treatment of kidney injury is rarely reported. Herein, the ROS responsive red blood cell-membrane-coated resatorvid-loaded cerium oxide nanoparticles (RBCM@CeO2/TAK-242) are constructed to suppress CaOx induced kidney injury and crystals deposition. In vitro, RBCM@CeO2/TAK-242 shows effective internalization by renal tubular epithelial cells, along with demonstrated antioxidative, anti-inflammatory, and macrophage reprogramming effects. Glyoxalate(Gly)-induced renal CaOx crystals mouse model is established, RBCM@CeO2/TAK-242 shows excellent injured kidney targeting and biosafety, and could effectively suppress CaOx induced kidney injury and crystals deposition. RBCM@CeO2/TAK-242 has a dual protective effect by both inhibiting oxidative stress and modulating macrophage polarization in vivo. In addition, RNA seq analysis reveals that RBCM@CeO2/TAK-242 protects against CaOx induced kidney injury via suppressing the TLR4/NF-κB pathway. This study provides an innovative strategy for RBCM@CeO2/TAK-242 as injured kidney targeting and dual protective effects for the treatment of CaOx induced kidney injury and crystals deposition.

ROS-responsive nanoparticles for bioimaging and treating acute lung injury by releasing dexamethasone and improving alveolar macrophage homeostasis

BackgroundAcute lung injury (ALI) triggers the activation of pulmonary macrophages, which in turn produce excessive amounts of reactive oxygen species (ROS).ResultsWe synthesized ROS-responsive red light-emitting carbon dots (RCMNs) that target lung macrophages, possess bioimaging capabilities, and efficiently eliminate intracellular ROS, thereby demonstrating anti-inflammatory effects for treating acute lung injury (ALI). In an LPS-induced ALI mouse model, RCMNs showed bioimaging and therapeutic potential, reducing lung damage and inflammation by targeting ROS-damaged tissue. RCMNs also improved alveolar macrophage activity, decreased inflammatory cytokines (TNF-α and IL-6), and enhanced survival in endotoxic shock, indicating their therapeutic potential for ALI. RNA-seq analysis revealed that RCMNs modulate signaling pathways related to calcium, TNF, and Toll-like receptors, highlighting their role in regulating inflammation and immune responses. Mechanistically, RCMNs alleviate inflammation in ALI by enhancing mitochondrial function in lung macrophages, as evidenced by improved mitochondrial morphology and membrane potential.ConclusionsThis protective effect is mediated through the regulation of intracellular Ca2+ levels and mitochondrial respiratory chain complexes, suggesting RCMNs as a therapeutic strategy for mitochondrial dysfunction in ALI.Graphical

Reactive Oxygen Species-Responsive Chitosan-Bilirubin Nanoparticles Loaded with Statin for Treatment of Cerebral Ischemia.

Cerebral ischemia impairs blood circulation, leading to elevated reactive oxygen species (ROS) production. A ROS-responsive delivery of drugs can enhance the therapeutic efficacy and minimize the side effects. There is insufficient evidence on the impact of ROS-responsive nanoparticles on ischemic stroke. We developed ROS-responsive chitosan-bilirubin (ChiBil) nanoparticles to target acute ischemic lesions and investigated the effect of atorvastatin-loaded ROS-responsive ChiBil. We randomly assigned rats with transient middle cerebral artery occlusion (MCAO) to 4 groups: saline, Statin, ChiBil, and ChiBil-Statin. These groups were treated daily via the tail vein for 7 d. Behavioral assessment, magnetic resonance (MR) imaging, evaluation of neuroinflammation, blood-brain barrier (BBB) integrity, apoptosis, and neurogenesis after stroke were conducted. Invitro, results showed nanoparticle uptake and reduced intracellular ROS, lipid peroxidation, and inflammatory cytokines (IL-6 and TNF-α). Invivo, results showed improved motor deficits and decreased infarct volumes on MR images in the ChiBil-Statin group compared with the Control group on day 7 (P < 0.05). Furthermore, the expression of inflammatory cytokines such as IL-1β and IL-6 was reduced in the ChiBil-Statin group compared with the Control group (P < 0.05). Improvements in BBB integrity, apoptosis, and neurogenesis were observed in the ChiBil-Statin group. The findings demonstrated that intravenous ROS-responsive multifunctional ChiBil-Statin could effectively deliver drugs to the ischemic brain, exerting marked synergistic pleiotropic neuroprotective effects. Therefore, ChiBil-Statin holds promise as a targeted therapy for ischemic vascular diseases characterized by increased ROS production, leading to new avenues for future research and potential clinical applications.

Maltodextrin-derived nanoparticles resensitize intracellular dormant Staphylococcus aureus to rifampicin

Intracellular bacteria are recognized as a crucial factor in the persistence and recurrence of infections. The efficacy of current antibiotic treatments faces substantial challenges due to the dormant state formation of intracellular bacteria. In this study, we devised a strategy aimed at reverting intracellular dormant bacteria to a metabolically active state, thereby increasing their vulnerability to antibiotics. We found that oligosaccharides, especially maltodextrin (MD), can be absorbed by dormant S. aureus, leading to their revival and restoration of sensitivity to rifampicin (Rif). We then synthesized a reactive oxygen species (ROS)-responsive MD-prodrug by covalently binding MD with 4-(hydroxymethyl) phenylboronic acid pinacol ester (MD-PBAP) and prepared a ROS-responsive nanoparticles (MDNP) using a nanoprecipitation and self-assembly method. Once internalized by host cells, MDNP was degraded to MD, reactivating dormant S. aureus, and enhancing their susceptibility to Rif. More importantly, MDNP treatment restored the sensitivity of intracellular persistent S. aureus to Rif in both a reservoir transfer model and whole-body infection model. Additionally, MDNP have demonstrated excellent biocompatibility in both in vitro and in vivo settings. These results offer a promising therapeutic avenue for managing persistent intracellular bacterial infections by reviving and resensitizing intracellular dormant bacteria to conventional antibiotics.

ROS-Responsive Nanoparticles with Antioxidative Effect for the treatment of Diabetic Retinopathy

Diabetic retinopathy (DR) is a common microvascular complication of diabetes necessitating early intervention to impede progression, despite current clinical treatments focusing on advanced stages. Essential oils from Fructus Alpiniae zerumbet (EOFAZ) have demonstrated efficacy in protecting against high glucose (HG)-induced Müller cell activation and DR development. This study introduced a reactive oxidative species (ROS)-responsive drug delivery system (NPSPHE@EOFAZ) targeting early DR stages and oxidative stress. Our engineered nanoparticles effectively deliver EOFAZ into HG-exposed Müller cells by detecting and responding to elevated oxidative stress levels. The NPSPHE@EOFAZ significantly inhibited abnormal cell growth, reduced oxidative stress, and alleviated inflammation in vitro. In vivo experiments on diabetic mice with DR revealed that NPSPHE@EOFAZ mitigated early pathological changes by reducing oxidative stress and inflammation while also alleviating organ damage in the heart, liver, spleen, lung, and kidney. These findings underscore the potential of NPSPHE@EOFAZ as a promising antioxidant for early intervention in DR pathogenesis.

ROS-responsive nanoparticle delivery of obeticholic acid mitigate primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) is a challenging cholestatic liver disease marked by progressive bile duct inflammation and fibrosis that has no FDA-approved therapy. Although obeticholic acid (OCA) has been sanctioned for PSC, its clinical utility in PSC is constrained by its potential hepatotoxicity. Here, we introduce a novel therapeutic construct consisting of OCA encapsulated within a reactive oxygen species (ROS)-responsive, biodegradable polymer, further cloaked with human placenta-derived mesenchymal stem cell (hP-MSC) membrane (MPPFTU@OCA). Using PSC patient-derived organoid models, we assessed its cellular uptake and cytotoxicity. Moreover, using a PSC mouse model induced by 3,5-diethoxycarbonyl-1,4-dihydro-collidine (DDC), we demonstrated that intravenous administration of MPPFTU@OCA not only improved cholestasis via the FXR-SHP pathway but also reduced macrophage infiltration and the accumulation of intracellular ROS, and alleviated mitochondria-induced apoptosis. Finally, we verified the ability of MPPFTU@OCA to inhibit mitochondrial ROS thereby alleviating apoptosis by measuring the mitochondrial adenosine triphosphate (ATP) concentration, ROS levels, and membrane potential (ΔΨm) using H2O2-stimulated PSC-derived organoids. These results illuminate the synergistic benefits of integrating an ROS-responsive biomimetic platform with OCA, offering a promising therapeutic avenue for PSC.

Inflammatory macrophage reprogramming strategy of fucoidan microneedles-mediated ROS-responsive polymers for rheumatoid arthritis

During the pathogenesis of rheumatoid arthritis, inflammatory cells usually infiltrate synovial tissues, notably, M1-type macrophages, whose redox imbalance leads to the degradation of joint structures and deterioration of function. Natural active products play a vital role in immune modulation and antioxidants. In this study, we constructed a ROS-responsive nanoparticle called FTL@SIN, which consists of fucoidan (Fuc) and luteolin (Lut) connected by a ROS-responsive bond, Thioketal (TK), and encapsulated with an anti-rheumatic drug, Sinomenine (SIN), for synergistic anti-inflammatory effects. The FTL@SIN is then dispersed in high molecular weight Fuc-fabricated dissolvable microneedles (FTL@SIN MNs) for local administration. Therapy of FTL@SIN MNs afforded a significant decrease in macrophage inflammation while decreasing key pro-inflammatory cytokines and repolarizing M1 type to M2 type, thereby ameliorating synovial inflammation, and promoting cartilage repair. Additionally, our investigations have revealed that Fucoidan (Fuc) demonstrates synergistic effects, exhibiting superior mechanical strength and enhanced physical stability when compared to microneedles formulated solely with hyaluronic acid. This study combines nanomedicine with traditional Chinese medicine, a novel drug delivery strategy that presents a promising avenue for therapeutic intervention in rheumatoid arthritis.

ROS-responsive nanoparticle delivery of ferroptosis inhibitor prodrug to facilitate mesenchymal stem cell-mediated spinal cord injury repair

Spinal cord injury (SCI) is a traumatic condition that results in impaired motor and sensory function. Ferroptosis is one of the main causes of neural cell death and loss of neurological function in the spinal cord, and ferroptosis inhibitors are effective in reducing inflammation and repairing SCI. Although human umbilical cord mesenchymal stem cells (Huc-MSCs) can ameliorate inflammatory microenvironments and promote neural regeneration in SCI, their efficacy is greatly limited by the local microenvironment after SCI. Therefore, in this study, we constructed a drug-release nanoparticle system with synergistic Huc-MSCs and ferroptosis inhibitor, in which we anchored Huc-MSCs by a Tz-A6 peptide based on the CD44-targeting sequence, and combined with the reactive oxygen species (ROS)-responsive drug nanocarrier mPEG-b-Lys-BECI-TCO at the other end for SCI repair. Meanwhile, we also modified the classic ferroptosis inhibitor Ferrostatin-1 (Fer-1) and synthesized a new prodrug Feborastatin-1 (Feb-1). The results showed that this treatment regimen significantly inhibited the ferroptosis and inflammatory response after SCI, and promoted the recovery of neurological function in rats with SCI. This study developed a combination therapy for the treatment of SCI and also provides a new strategy for the construction of a drug-coordinated cell therapy system.

Monitoring ROS Responsive Fe3O4-based Nanoparticle Mediated Ferroptosis and Immunotherapy via 129Xe MRI.

The immune checkpoint blockade strategy has improved the survival rate of late-stage lung cancer patients. However, the low immune response rate limits the immunotherapy efficiency. Here, we report a ROS-responsive Fe3O4-based nanoparticle that undergoes charge reversal and disassembly in the tumor microenvironment, enhancing the uptake of Fe3O4 by tumor cells and triggering a more severe ferroptosis. In the tumor microenvironment, the nanoparticle rapidly disassembles and releases the loaded GOx and the immune-activating peptide Tuftsin under overexpressed H2O2. GOx can consume the glucose of tumor cells and generate more H2O2, promoting the disassembly of the nanoparticle and drug release, thereby enhancing the therapeutic effect of ferroptosis. Combined with Tuftsin, it can more effectively reverse the immune-suppressive microenvironment and promote the recruitment of effector T cells in tumor tissues. Ultimately, in combination with α-PD-L1, there is significant inhibition of the growth of lung metastases. Additionally, the hyperpolarized 129Xe method has been used to evaluate the Fe3O4 nanoparticle-mediated immunotherapy, where the ventilation defects in lung metastases have been significantly improved with complete lung structure and function recovered. The ferroptosis-enhanced immunotherapy combined with non-radiation evaluation methodology paves a new way for designing novel theranostic agents for cancer therapy.

ROS-responsive nanoparticles targeting inflamed colon for synergistic therapy of inflammatory bowel disease via barrier repair and anti-inflammation

ROS-responsive nanoparticles targeting inflamed colon for synergistic therapy of inflammatory bowel disease via barrier repair and anti-inflammation

ICAM-1 targeted and ROS-responsive nanoparticles for the treatment of acute lung injury.

Acute lung injury (ALI) is an inflammatory disease caused by multiple factors such as infection, trauma, and chemicals. Without effective intervention during the early stages, it usually quickly progresses to acute respiratory distress syndrome (ARDS). Since ordinary pharmaceutical preparations cannot precisely target the lungs, their clinical application is limited. In response, we constructed a γ3 peptide-decorated and ROS-responsive nanoparticle system encapsulating therapeutic dexamethasone (Dex/PSB-γ3 NPs). In vitro, Dex/PSB-γ3 NPs had rapid H2O2 responsiveness, low cytotoxicity, and strong intracellular ROS removal capacity. In a mouse model of ALI, Dex/PSB-γ3 NPs accumulated at the injured lung rapidly, alleviating pulmonary edema and cytokine levels significantly. The modification of NPs by γ3 peptide achieved highly specific positioning of NPs in the inflammatory area. The ROS-responsive release mechanism ensured the rapid release of therapeutic dexamethasone at the inflammatory site. This combined approach improves treatment accuracy, and drug bioavailability, and effectively inhibits inflammation progression. Our study could effectively reduce the risk of ALI progressing to ARDS and hold potential for the early treatment of ALI.

ROS-responsive self-assembly nanoplatform overcomes hypoxia for enhanced photodynamic therapy.

Photodynamic therapy (PDT) has emerged as a promising treatment for malignant tumours in recent decades due to its impressive spatiotemporal selectivity, minimal invasiveness, and few adverse effects. Despite these advancements, there remain significant challenges in effectively delivering photosensitizers to tumours and overcoming tumour hypoxia to maximize the therapeutic benefits of PDT. Ongoing research efforts are focused on developing innovative strategies to overcome the above-mentioned challenges, such as nanoplatforms and combination therapy approaches. Hence, reactive oxygen species (ROS)-responsive polymeric micelles are promising candidates to enhance the distribution and retention of photosensitizers within tumours. Additionally, efforts to alleviate tumour hypoxia may further improve the anti-tumour effects of PDT. In this study, we designed ROS-responsive polymeric micelles (TC@PTP) co-loaded with a Tapp-COF, a porphyrin derivative, and capsaicin for PDT of melanoma. These ROS-responsive nanocarriers, constructed from thioketal (TK)-linked amphiphilic di-block copolymers (PEG5K-TK-PLGA5K), could accumulate in the tumor microenvironment and release drugs under the action of ROS. Capsaicin, acting as a biogenic respiratory inhibitor, suppressed mitochondrial respiration and the hypoxia-inducible factor 1 (HIF-1) signaling pathway, thereby increasing oxygen levels at the tumour site. These PDT-triggered ROS-responsive nanoparticles effectively alleviated the tumour hypoxic microenvironment and enhanced anti-tumour efficacy. With superior biocompatibility and tumour-targeting abilities, the platform holds great promise for advancing anti-tumour combination therapy.

Free drug and ROS-responsive nanoparticle delivery of synergistic doxorubicin and olaparib combinations to triple negative breast cancer models.

Combinations of the topoisomerase II inhibitor doxorubicin and the poly (ADP-ribose) polymerase inhibitor olaparib offer potential drug-drug synergy for the treatment of triple negative breast cancers (TNBC). In this study we performed in vitro screening of combinations of these drugs, administered directly or encapsulated within polymer nanoparticles, in both 2D and in 3D spheroid models of breast cancer. A variety of assays were used to evaluate drug potency, and calculations of combination index (CI) values indicated that synergistic effects of drug combinations occurred in a molar-ratio dependent manner. It is suggested that the mechanisms of synergy were related to enhancement of DNA damage as shown by the level of double-strand DNA breaks, and mechanisms of antagonism associated with mitochondrial mediated cell survival, as indicated by reactive oxygen species (ROS) generation. Enhanced drug delivery and potency was observed with nanoparticle formulations, with a greater extent of doxorubicin localised to cell nuclei as evidenced by microscopy, and higher cytotoxicity at the same time points compared to free drugs. Together, the work presented identifies specific combinations of doxorubicin and olaparib which were most effective in a panel of TNBC cell lines, explores the mechanisms by which these combined agents might act, and shows that formulation of these drug combinations into polymeric nanoparticles at specific ratios conserves synergistic action and enhanced potency in vitro compared to the free drugs.

Stimuli-responsive nanoparticles delivered by a nasal-brain pathway alleviate depression-like behavior through extensively scavenging ROS.

Depression is one of the most common mental diseases, which seriously affects patients' physical and mental health. Emerging evidence has indicated that oxidative stress (OS) is a major cause of neurodegeneration involved in the pathogenesis of depression. Consequently, targeted reactive oxygen species (ROS) elimination is regarded as a promising strategy for efficient depression therapy. In addition, insufficient brain drug delivery is the main obstacle to depression therapy owing to the presence of the blood-brain barrier (BBB). To achieve the goals of bypassing the BBB and promoting antioxidant therapy for depression, a broad-spectrum ROS scavenging NPs was rationally designed through a nasal-brain pathway developed for combined ROS scavenging and brain drug delivery. A hexa-arginine (R6) modified ROS-responsive dextran (DEX) derivate was synthesized for antidepressant olanzapine (Olz) and H2 donor amino borane (AB) loading to prepare Olz/RDPA nanoparticles (NPs). Subsequently, the NPs were dispersed into a thermoresponsive hydrogel system based on poloxamer. In vitro and in vivo results demonstrated that Olz/RDPA in situ thermoresponsive hydrogel system could effectively deliver NPs to the brain via the nasal-brain pathway and alleviate depression-like behaviors through combined ROS depletion and inhibition of 5-HT dysfunction of the oxidative stress-induced. The proposed ROS-scavenging nanotherapeutic would open a new window for depression treatment. STATEMENT OF SIGNIFICANCE: ROS is an innovative therapeutic target involving the pathology of depression whereas targeted delivery of ROS scavenging has not been achieved yet. In the current study, ROS-responsive nanoparticles (Olz/RDPA NPs) were prepared and dispersed in a thermosensitive hydrogel for delivery through the nasal-brain pathway for the treatment of depression. Sufficient ROS depletion and improvement of delivery capacity by the nasal-brain pathway effectively could reverse oxidative stress and alleviate depressive-like behavior. Collectively, these nanoparticles may represent a promising strategy for the treatment of depression.

ROS Responsive Nanoparticles Encapsulated with Natural Medicine Remodel Autophagy Homeostasis in Breast Cancer.

In photodynamic therapy (PDT), elevated reactive oxygen species (ROS) activate tumor cell protective autophagy, therefore attenuating the antitumor function of therapy. Hence, inhibition of protective autophagy in tumors can improve the antitumor effect of PDT. Herein, an innovative nanotraditional Chinese medicine system ((TP+A)@TkPEG NPs), which remodeled autophagy homeostasis, was fabricated. A photosensitizer aggregation inducing emission (AIE) and autophagy modulator triptolide (TP, an active ingredient of Tripterygium wilfordii Hook F) were encapsulated into ROS-responsive nanoparticles to improve antitumor effect of PDT in treatment of triple negative breast cancer. We proved that (TP+A)@TkPEG NPs effectively elevated intracellular ROS levels, activated ROS-responsive release of TP and inhibited the proliferation of 4T1 cells in vitro. More importantly, it sharply reduced autophagy related genes transcription and proteins expression in 4T1 cells, then promote cell apoptosis. In addition, this nanoherb therapeutic system effectively orientated to tumor sites, achieved efficient inhibition of tumor, and extended the survival time of 4T1-bearing mice in vivo. Further results confirmed that (TP+A)@TkPEG NPs remarkably inhibit the expression level of autophagy related initiation gene (becline-1) and elongation protein (light chain 3B) in tumor microenvironment and then block PDT induced protective autophagy. In brief, this system can remodel autophagy homeostasis and serve as an innovative approach for treatment of triple negative breast cancer.

Hybrid Shear-thinning Hydrogel Integrating Hyaluronic Acid with ROS-Responsive Nanoparticles.

Nanoparticle (NP) supra-assembly offers unique opportunities to tune macroscopic hydrogels' mechanical strength, material degradation, and drug delivery properties. Here, synthetic, reactive oxygen species (ROS)-responsive NPs are physically crosslinked with hyaluronic acid (HA) through guest-host chemistry to create shear-thinning NP/HA hydrogels. A library of triblock copolymers composed of poly(propylene sulfide)-bl-poly(N,N-dimethylacrylamide)-bl-poly(N,N-dimethylacrylamide-co-N-(1-adamantyl)acrylamide) are synthesized with varied triblock architectures and adamantane grafting densities and then self-assembled into NPs displaying adamantane on their corona. Self-assembled NPs are mixed with β-cyclodextrin grafted HA to yield eighteen NP/HA hydrogel formulations. The NP/HA hydrogel platform demonstrates superior mechanical strength to HA-only hydrogels, susceptibility to oxidative/enzymatic degradation, and inherent cell-protective, antioxidant function. The performance of NP/HA hydrogels is shown to be affected by triblock architecture, guest/host grafting densities, and HA composition. In particular, the length of the hydrophilic second block and adamantane grafting density of self-assembled NPs significantly impacts hydrogel mechanical properties and shear-thinning behavior, while ROS-reactivity of poly(propylene sulfide) protects cells from cytotoxic ROS and reduces oxidative degradation of HA compared to HA-only hydrogels. This work provides insight into polymer structure-function considerations for designing hybrid NP/HA hydrogels and identifies antioxidant, shear-thinning hydrogels as promising injectable delivery platforms for small molecule drugs and therapeutic cells.

ROS-Responsive Nanoparticle Delivery of mRNA and Photosensitizer for Combinatorial Cancer Therapy.

Messenger RNA (mRNA) therapy has shown tremendous potential for different diseases including cancer. While mRNA has been extensively used in cancer vaccine development as antigen or in cancer immunotherapy as immunomodulatory agent, the combination of mRNA therapy with photodynamic therapy has not been explored in cancer treatment. Herein, we report a reactive oxygen species (ROS)-responsive polymeric nanoparticle (NP) platform for first-in-field codelivery of mRNA and photosensitizer for effective cancer treatment. We developed ROS-responsive oligomer-based polymeric NPs and applied them to test a combination of p53 mRNA and indocyanine green (ICG). The ROS-triggered disassembly of the NPs could promote mRNA translation efficiency, whereby p53 expression induced apoptosis of lung tumor cells. Meanwhile, the released ICG could lead to generation of ROS under 808 nm laser irradiation to induce photodynamic therapy. The NP codelivery of p53 mRNA and ICG demonstrated an effective and safe anti-tumor effect in a lung cancer model.

Paclitaxel-loaded ROS-responsive nanoparticles for head and neck cancer therapy

High intracellular reactive oxygen species (ROS) level is characteristic of cancer cells and could act as a target for the efficient targeted drug delivery for cancer treatment. Consequently, biomaterials that react to excessive levels of ROS are essential for biomedical applications. In this study, a novel ROS-responsive polymer based on D-α-Tocopheryl polyethylene glycol 1000 succinate (TPGS) and poly (β-thioester) (TPGS-PBTE) was synthesized for targeted delivery of the first-line antineoplastic drug, paclitaxel (PTX). The resultant TPGS-PBTE NPs showed good ROS-responsive capability in size change and drug release. Compared to PTX, PTX-loaded nanoparticles (PTX@TPGS-PBTE NPs) showed enhanced cytotoxicity and higher level of apoptosis toward squamous cell carcinoma (SCC-7) cells. Tumor-targeted delivery of the NPs was also observed, especially after being modified with a tumor-targeting peptide, cRGD. Enhanced tumor growth inhibition was also observed in head and neck cancer SCC-7 murine models. In summary, PTX@TPGS-PBTE NPs can achieve good therapeutic effects of PTX against head and neck cancer both in vitro and in vivo, especially when modified by cRGD for active targeting, which enriched the application of ROS responsive system utilized in the delivery of anticancer drugs.

Stimulus-responsive curcumin-based polydopamine nanoparticles for targeting Parkinson’s disease by modulating α-synuclein aggregation and reactive oxygen species

Parkinson’s disease (PD) is the second most common neurodegenerative disease, posing a significant threat to an individual’s health, particularly among the elderly. An incomplete understanding of the pathogenesis underlying PD renders the single therapeutic model ineffective. Oxidative stress and abnormal alpha-synuclein (α-Syn) aggregation are two crucial factors accounting for dopaminergic neuron loss. Therefore, combined PD therapy that inhibits and reduces α-Syn aggregation and regulates the balance of reactive oxygen species (ROS) holds promise. In this study a novel nanodrug, polydopamine-based curcumin-loaded nanoparticles (PC NPs), based on polydopamine (PDA)-assembled curcumin (Cur) nanoparticles was designed, which was then modified with a peptide obtained from rabies virus glycoprotein (RVG) 29 (obtained RPC NPs) to target the brain. Cur and PDA of ROS-responsive nanoparticles (RPC NPs) significantly scavenged a broad spectrum of ROS. Cur inhibited and removed α-Syn aggregation, thus protecting PC12 cells from rotenone-induced cell death. RPC NPs were also shown to prolong the lifespan of Caenorhabditis elegans and restored dopamine-dependent behaviors, including area-restricted searching, ethanol avoidance, and the basal slowing response, by using 6-hydroxydopamine (6-OHDA)-pretreated C. elegans wild-type Bristol (N2) and the nematode transgenic hus111 strain as models. In vivo animal studies showed that RPC NPs significantly lowered dopaminergic neuron damage and improved the neurobehavioral abnormalities in PD mice, while having no noticeable systemic side effects. RPC NPs also decreased α-Syn accumulation and reduced oxidative stress in the striatum and substantia nigra. This multifunctional synergetic strategy may provide a new candidate for highly efficient combination therapy in patients with PD.

Oxidative Stress Amplifiers as Immunogenic Cell Death Nanoinducers Disrupting Mitochondrial Redox Homeostasis for Cancer Immunotherapy.

Reactive oxygen species (ROS)-induced oxidative stress in the endoplasmic reticulum (ER) is generally believed to be an important prerequisite for immunogenic cell death (ICD) which can trigger antitumor immune responses for cancer immunotherapy. However, thus far, little is known between the oxidative stress in a certain organelle other than ER and ICD. Herein, polymers for preparing ROS-responsive nanoparticles (NP-I-CA-TPP) with mitochondrial targeting performance as ICD nanoinducers are designed. It is believed that NP-I-CA-TPP can target mitochondria which are extremely important organelles intimately involved in cellular stress signaling to play an important role in the induction of ICD. NP-I-CA-TPP can amplify cinnamaldehyde (CA)-induced ROS damage by iodo-thiol click chemistry-mediated glutathione depletion in cancer cells. Finally, NP-I-CA-TPP is shown to disrupt mitochondrial redox homeostasis, amplify mitochondrial oxidative stress, promote cancer cell apoptosis via inducing ICD, and triggering the body's antitumor immune response for cancer immunotherapy.