Puerarin-Loaded Liposomes Co-Modified by Ischemic Myocardium-Targeting Peptide and Triphenylphosphonium Cations Ameliorate Myocardial Ischemia-Reperfusion Injury.

Purpose: Mitochondrial damage may lead to uncontrolled oxidative stress and massive apoptosis, and thus plays a pivotal role in the pathological processes of myocardial ischemia-reperfusion (I/R) injury. However, it is difficult for the drugs such as puerarin (PUE) to reach the mitochondrial lesion due to lack of targeting ability, which seriously affects the expected efficacy of drug therapy for myocardial I/R injury. Methods: We prepared triphenylphosphonium (TPP) cations and ischemic myocardium-targeting peptide (IMTP) co-modified puerarin-loaded liposomes (PUE@T/I-L), which effectively deliver the drug to mitochondria and improve the effectiveness of PUE in reducing myocardial I/R injury. Results: In vitro test results showed that PUE@T/I-L had sustained release and excellent hemocompatibility. Fluorescence test results showed that TPP cations and IMTP double-modified liposomes (T/I-L) enhanced the intracellular uptake, escaped lysosomal capture and promoted drug targeting into the mitochondria. Notably, PUE@T/I-L inhibited the opening of the mitochondrial permeability transition pore, reduced intracellular reactive oxygen species (ROS) levels and increased superoxide dismutase (SOD) levels, thereby decreasing the percentage of Hoechst-positive cells and improving the survival of hypoxia-reoxygenated (H/R)-injured H9c2 cells. In a mouse myocardial I/R injury model, PUE@T/I-L showed a significant myocardial protective effect against myocardial I/R injury by protecting mitochondrial integrity, reducing myocardial apoptosis and decreasing infarct size. Conclusion: This drug delivery system exhibited excellent mitochondrial targeting and reduction of myocardial apoptosis, which endowed it with good potential extension value in the precise treatment of myocardial I/R injury.

Real-world evidence of brigatinib as second-line treatment after crizotinib for ALK+ non-small cell lung cancer using South Korean claims data (K-AREAL).

PURPOSE: There is a lack of real-world data in Asian populations for brigatinib, a next-generation anaplastic lymphoma kinase (ALK) inhibitor for patients with non-small cell lung cancer (NSCLC). This study analysed real-world outcomes and dosing patterns for brigatinib in patients with crizotinib-refractory ALK+ NSCLC in South Korea. METHODS: This retrospective, non-interventional, cohort study used South Korean Health Insurance and Review Assessment claims data for adults with ALK+ NSCLC who initiated brigatinib between 19 April 2019 and 31 March 2021 after receiving prior crizotinib. Patients' characteristics, time to discontinuation (TTD), time to dose reduction, overall survival (OS) and treatment adherence were assessed. RESULTS: The study included 174 patients (56.9% male; 27.0% with a history of brain metastases). Median duration of prior crizotinib was 17 (range 0.3-48) months. Median follow-up after brigatinib initiation was 18 (range 0-34) months. Overall, 88.5% of patients received full-dose brigatinib (180 mg/day) and 93.1% of patients were adherent (proportion of days covered ≥0.8). The median TTD was 24.9 months (95% CI 15.2-not reached). The probability of continuing treatment was 63.2% at 1 year and 51.5% at 2 years. The probability of continuing at full or peak dose was 79.7% at 1 year and 75.6% at 2 years. Median OS was not reached. The 2-year OS rate was 68.7%. CONCLUSIONS: In this first nationwide retrospective study using national insurance claim data, brigatinib demonstrated real-world clinical benefit as second-line treatment after prior crizotinib in ALK+ NSCLC patients in South Korea.

Successful intracranial response of lorlatinib after resistance with alectinib and brigatinib in patients with ALK-positive lung adenocarcinoma: Implications of CNS penetration rate of brigatinib.

We present the case of a 34-year-old Japanese man with anaplastic lymphoma kinase (ALK)-positive non-small cell lung cancer and brain metastases. After central nervous system (CNS) disease progression with alecintib and brigatinib, treatment with lorlatinib resulted in a good intracranial response. In this case, we investigated brain penetration ratio of brigatinib using cerebrospinal fluid and paired serum samples, and the ratio was 0.012. Further, we investigated resistance mechanisms via next-generation sequencing (NGS) using lung biopsy at lung cancer diagnosis and brain biopsy sample at progressive disease of brigatinib. No apparent resistance mechanism of known ALK resistance, such as ALK mutations, amplifications, epithelial-mesenchymal transition (EMT) and bypass pathway activation were detected. Taken together, we speculate that the low CNS penetration rate of brigatinib confers CNS progression. Further studies are warranted to reveal the resistance mechanism and propose a treatment strategy for CNS progression in ALK-positive patients.

Lipo/TK-CDN/TPP/Y6 nanoparticles inhibit cutaneous melanoma formation.

Stimulation of the innate immune stimulator of interferon genes (STING) pathway has been shown to boost anti-tumour immunity. Nevertheless, the systemic delivery of STING agonists to the tumour presents challenges. Therefore, we designed a cyclic dinucleotide (CDN)-based drug delivery system (DDS) combined photothermal therapy (PTT)/photodynamic therapy (PDT)/immunotherapy for cutaneous melanoma. We coencapsulated a reactive oxygen species (ROS)-responsive prodrug thioketone-linked CDN (TK-CDN), and photoresponsive agents chlorin E6 (Y6) within mitochondria-targeting reagent triphenylphosphonium (TPP)-modified liposomes (Lipo/TK-CDN/TPP/Y6). Lipo/TK-CDN/TPP/Y6 exhibited a photothermal effect similar to Y6, along with a superior cellular uptake rate. Upon endocytosis by B16F10 cells, Lipo/TK-CDN/TPP/Y6 generated large amounts of ROS under laser irradiation for PDT. Mice bearing B16F10 tumours were intravenously injected with Lipo/TK-CDN/TPP/Y6 and exposed to irradiation, resulting in a substantial inhibition of tumour growth. Exploration of the mechanism of anti-tumour action showed that Lipo/TK-CDN/TPP/Y6 had a stronger stimulation of STING activation and anti-tumour immune cell infiltration compared to other groups. Hence, the Lipo/TK-CDN/TPP/Y6 nanoparticles offer great potential as a DDS for targeted and on-demand drug release at tumour sites. These nanoparticles exhibit promise as a candidate for precise and controllable combination therapy in the treatment of tumours.

Brigatinib in NF2-Related Schwannomatosis with Progressive Tumors.

BACKGROUND: NF2-related schwannomatosis (NF2-SWN, formerly called neurofibromatosis type 2) is a tumor predisposition syndrome that is manifested by multiple vestibular schwannomas, nonvestibular schwannomas, meningiomas, and ependymomas. The condition is relentlessly progressive with no approved therapies. On the basis of preclinical activity of brigatinib (an inhibitor of multiple tyrosine kinases) in NF2-driven nonvestibular schwannoma and meningioma, data were needed on the use of brigatinib in patients with multiple types of progressive NF2-SWN tumors. METHODS: In this phase 2 platform trial with a basket design, patients who were 12 years of age or older with NF2-SWN and progressive tumors were treated with oral brigatinib at a dose of 180 mg daily. A central review committee evaluated one target tumor and up to five nontarget tumors in each patient. The primary outcome was radiographic response in target tumors. Key secondary outcomes were safety, response rate in all tumors, hearing response, and patient-reported outcomes. RESULTS: A total of 40 patients (median age, 26 years) with progressive target tumors (10 vestibular schwannomas, 8 nonvestibular schwannomas, 20 meningiomas, and 2 ependymomas) received treatment with brigatinib. After a median follow-up of 10.4 months, the percentage of tumors with a radiographic response was 10% (95% confidence interval [CI], 3 to 24) for target tumors and 23% (95% CI, 16 to 30) for all tumors; meningiomas and nonvestibular schwannomas had the greatest benefit. Annualized growth rates decreased for all tumor types during treatment. Hearing improvement occurred in 35% (95% CI, 20 to 53) of eligible ears. Exploratory analyses suggested a decrease in self-reported pain severity during treatment (-0.013 units per month; 95% CI, -0.002 to -0.029) on a scale from 0 (no pain) to 3 (severe pain). No grade 4 or 5 treatment-related adverse events were reported. CONCLUSIONS: Brigatinib treatment resulted in radiographic responses in multiple tumor types and clinical benefit in a heavily pretreated cohort of patients with NF2-SWN. (Funded by the Children's Tumor Foundation and others; INTUITT-NF2 ClinicalTrials.gov number, NCT04374305.).

Construction of mitochondrial-targeting nano-prodrug for enhanced Rhein delivery and treatment for osteoarthritis in vitro.

Rhein, a natural anthraquinone compound derived from traditional Chinese medicine, exhibits potent anti-inflammatory properties via modulating the level of Reactive oxygen or nitrogen species (RONS). Nevertheless, its limited solubility in water, brief duration of plasma presence, as well as its significant systemic toxicity, pose obstacles to its in vivo usage, necessitating the creation of a reliable drug delivery platform to circumvent these difficulties. In this study, an esterase-responsive and mitochondria-targeted nano-prodrug was synthesized by conjugating Rhein with the polyethylene glycol (PEG)-modified triphenyl phosphonium (TPP) molecule, forming TPP-PEG-RH, which could spontaneously self-assemble into RPT NPs when dispersed in aqueous media. The TPP outer layer of these nanoparticles enhances their pharmacokinetic profile, facilitates efficient delivery to mitochondria, and promotes cellular uptake, thereby enabling enhanced accumulation in mitochondria and improved therapeutic effects in vitro. The decline in RONS was observed in IL-1ß-stimulated chondrocyte after RPT NPs treating. RPT NPs also exert excellent anti-inflammatory (IL-1ß, TNF-α, IL-6 and MMP-13) and antioxidative effects (Cat and Sod) via the Nrf2 signalling pathway, upregulation of cartilage related genes (Col2a1 and Acan). Moreover, RPT NPs shows protection of mitochondrial membrane potential and inhibition of chondrocyte apoptosis. Moreover, These findings suggest that the mitochondria-targeted polymer-Rhein conjugate may offer a therapeutic solution for patients suffering from chronic joint disorders, by attenuating the progression of osteoarthritis (OA).

Therapeutic effects of mitoquinol during an acute heat stress challenge in growing barrows.

Study objectives were to determine the effects of mitoquinol (MitoQ, a mitochondrial-targeted antioxidant) on biomarkers of metabolism and inflammation during acute heat stress (HS). Crossbred barrows [n = 32; 59.0 ±â€…5.6 kg body weight (BW)] were blocked by BW and randomly assigned to 1 of 4 environmental-therapeutic treatments: 1) thermoneutral (TN) control (n = 8; TNCon), 2) TN and MitoQ (n = 8; TNMitoQ), 3) HS control (n = 8; HSCon), or 4) HS and MitoQ (n = 8; HSMitoQ). Pigs were acclimated for 6 d to individual pens before study initiation. The trial consisted of two experimental periods (P). During P1 (2 d), pigs were fed ad libitum and housed in TN conditions (20.6 ±â€…0.8 °C). During P2 (24 h), HSCon and HSMitoQ pigs were exposed to continuous HS (35.2 ±â€…0.2 °C), while TNCon and TNMitoQ remained in TN conditions. MitoQ (40 mg/d) was orally administered twice daily (0700 and 1800 hours) during P1 and P2. Pigs exposed to HS had increased rectal temperature, skin temperature, and respiration rate (+1.5 °C, +6.8 °C, and +101 breaths per minute, respectively; P < 0.01) compared to their TN counterparts. Acute HS markedly decreased feed intake (FI; 67%; P < 0.01); however, FI tended to be increased in HSMitoQ relative to HSCon pigs (1.5 kg vs. 0.9 kg, respectively; P = 0.08). Heat-stressed pigs lost BW compared to their TN counterparts (-4.7 kg vs. +1.6 kg, respectively; P < 0.01); however, the reduction in BW was attenuated in HSMitoQ compared to HSCon pigs (-3.9 kg vs. -5.5 kg, respectively; P < 0.01). Total gastrointestinal tract weight (empty tissue and luminal contents) was decreased in HS pigs relative to their TN counterparts (6.2 kg vs. 8.6 kg, respectively; P < 0.01). Blood glucose increased in HSMitoQ relative to HSCon pigs (15%; P = 0.04). Circulating non-esterified fatty acids (NEFA) increased in HS compared to TN pigs (P < 0.01), although this difference was disproportionately influenced by elevated NEFA in HSCon relative to HSMitoQ pigs (251 µEq/L vs. 142 µEq/L; P < 0.01). Heat-stressed pigs had decreased circulating insulin relative to their TN counterparts (47%; P = 0.04); however, the insulin:FI ratio tended to increase in HS relative to TN pigs (P = 0.09). Overall, circulating leukocytes were similar across treatments (P > 0.10). Plasma C-reactive protein remained similar among treatments; however, haptoglobin increased in HS relative to TN pigs (48%; P = 0.03). In conclusion, acute HS exposure negatively altered animal performance, inflammation, and metabolism, which were partially ameliorated by MitoQ.

Heat stress (HS) compromises animal health and productivity, and this causes major economic losses in almost every livestock sector. The negative consequences of HS are thought to originate from intestinal barrier dysfunction and subsequent immune activation. The underlying causes of lost intestinal integrity during HS are likely multifactorial; however, intestinal ischemia, increased accumulation of reactive oxygen species, and the ensuing epithelial oxidative damage might be potential causes. Mitochondria-targeted antioxidants, such as mitoquinol (MitoQ), are probably more effective than traditional dietary antioxidants (i.e., selenium, vitamin E) at alleviating oxidative stress, as they localize and accumulate within the mitochondria, potentiating their antioxidant activity. Thus, the present study aimed to investigate MitoQ's role during a thermal event in growing pigs. Herein, HS increased all body temperature indices, decreased feed intake (FI), and induced substantial body weight (BW) loss. Interestingly, the reduction in FI and BW was less dramatic in pigs receiving MitoQ. Changes in circulating metabolism and the acute phase response were observed due to the HS challenge; however, contrary to our expectations, these changes were not offset by MitoQ administration. Although our results suggest a positive MitoQ effect on growth performance, future studies are needed to corroborate the replicability of this response during HS.

Nano-Assembled Polyphosphazene Delivery System Enables Effective Intranasal Immunization with Nipah Virus Subunit Vaccine.

The ultimate vaccine against infections caused by Nipah virus should be capable of providing protection at the respiratory tract─the most probable port of entry for this pathogen. Intranasally delivered vaccines, which target nasal-associated lymphoid tissue and induce both systemic and mucosal immunity, are attractive candidates for enabling effective vaccination against this lethal disease. Herein, the water-soluble polyphosphazene delivery vehicle assembles into nanoscale supramolecular constructs with the soluble extracellular portion of the Hendra virus attachment glycoprotein─a promising subunit vaccine antigen against both Nipah and Hendra viruses. These supramolecular constructs signal through Toll-like receptor 7/8 and promote binding interactions with mucin─an important feature of effective mucosal adjuvants. High mass contrast of phosphorus-nitrogen backbone of the polymer enables a successful visualization of nanoconstructs in their vitrified state by cryogenic electron microscopy. Here, we characterize the self-assembly of polyphosphazene macromolecule with biologically relevant ligands by asymmetric flow field flow fractionation, dynamic light scattering, fluorescence spectrophotometry, and turbidimetric titration methods. Furthermore, a polyphosphazene-enabled intranasal Nipah vaccine candidate demonstrates the ability to induce immune responses in hamsters and shows superiority in inducing total IgG and neutralizing antibodies when benchmarked against the respective clinical stage alum adjuvanted vaccine. The results highlight the potential of polyphosphazene-enabled nanoassemblies in the development of intranasal vaccines.

Brigatinib combined with cetuximab in the fifth-line treatment of non-small cell lung cancer with EGFR p.C797S mutation in critically ill patients: a report of two cases and literature review.

For critically ill patients with non-small cell lung cancer (NSCLC) in need of life-saving treatment, there is currently no reported evidence regarding the use of medication specifically targeting epidermal growth factor receptor ( EGFR ) p.C797S mutation, which is known to cause resistance to third-generation tyrosine kinase inhibitors (TKIs). Our report aims to investigate and explore treatment strategies to overcome resistance associated with EGFR p.C797S mutation in order to provide potential therapeutic options for these patients. Here, we reported two cases with NSCLC who initially harbored an EGFR -sensitive mutation and were both treated with osimertinib, a third-generation TKI. Next-generation sequencing tests conducted prior to the initiation of fifth-line therapy in critically ill patients revealed the presence of EGFR p.C797S mutations in both patients, suggesting acquired resistance. In the course of fifth-line therapy, the administration of a combination of brigatinib and cetuximab proved vital in saving critically ill patients, moderately extending their overall survival period. Our findings suggested that a combined regimen of brigatinib and cetuximab could serve as a potentially life-saving therapeutic strategy for critically ill patients with NSCLC, particularly those demonstrating EGFR p.C797S-mediated resistance. Further studies, however, are required to validate and expand upon these promising findings.

Chitosan derivatives functionalized dual ROS-responsive nanocarriers to enhance synergistic oxidation-chemotherapy.

The efficient triggering of prodrug release has become a challengeable task for stimuli-responsive nanomedicine utilized in cancer therapy due to the subtle differences between normal and tumor tissues and heterogeneity. In this work, a dual ROS-responsive nanocarriers with the ability to self-regulate the ROS level was constructed, which could gradually respond to the endogenous ROS to achieve effective, hierarchical and specific drug release in cancer cells. In brief, DOX was conjugated with MSNs via thioketal bonds and loaded with ß-Lapachone. TPP modified chitosan was then coated to fabricate nanocarriers for mitochondria-specific delivery. The resultant nanocarriers respond to the endogenous ROS and release Lap specifically in cancer cells. Subsequently, the released Lap self-regulated the ROS level, resulting in the specific DOX release and mitochondrial damage in situ, enhancing synergistic oxidation-chemotherapy. The tumor inhibition Ratio was achieved to 78.49%. The multi-functional platform provides a novel remote drug delivery system in vivo.

Once-Daily Topical Phosphosulindac Is Efficacious in the Treatment of Dry Eye Disease: Studies in Rabbit Models of Its Main Clinical Subtypes.

Purpose: Dry eye disease (DED) is classified as aqueous deficient, evaporative, or mixed. We investigated the therapeutic effect of the novel anti-inflammatory drug phosphosulindac (PS) in rabbit models of DED encompassing its pathogenesis, and its transition to chronicity. Methods: We treated three rabbit models of DED with PS (hydrogel formulation) or vehicle topically applied 1 × /day. We induced aqueous-deficient DED (acute and chronic) by injecting Concanavalin A into lacrimal glands; evaporative DED by injecting into the upper eyelid inactivated Mycobacterium tuberculosis in complete Freund's adjuvant; and mixed DED through desiccative stress, induced by holding open the eye for 3 h. We determined corneal sensitivity, tear break-up time (TBUT), Schirmer's tear test (STT), tear osmolality, and fluorescein staining of the ocular surface. Results: PS reversed all abnormal DED parameters. In acute DED, PS dose dependently normalized corneal sensitivity and tear osmolality; and improved TBUT, STT, and fluorescein staining. PS normalized corneal sensitivity and improved all other parameters in chronic aqueous-deficient DED. In evaporative DED, PS normalized corneal sensitivity and improved TBUT and fluorescein staining (osmolality and STT were not significantly changed in this model). In the desiccative stress model, PS improved TBUT and fluorescein staining but had no effect on STT or tear osmolality. Conclusions: PS rapidly reversed almost all DED parameters in its three subtypes. The normalization of the suppressed corneal sensitivity suggests the possibility of marked symptomatic relief by PS. The hydrogel formulation allows once-daily dosing. PS merits further development as a potential treatment for DED.

A Mitochondrial Oxidative Stress Amplifier to Overcome Hypoxia Resistance for Enhanced Photodynamic Therapy.

Hypoxia-induced resistance to tumor treatment restricts further development of photodynamic therapy. Instead of simple reoxygenation to relieve hypoxia in traditional therapeutic approaches, a mitochondria-targeted reactive oxygen species (ROS) amplifier is constructed to reverse hypoxia resistance and enhance tumor sensitivity to hypoxia-resistant photodynamic therapy. Mesoporous silica nanoparticles are modified with triphenylphosphine to enhance its blood circulation and endow it with mitochondria-targeted specificity. α-Tocopherol succinate and indocyanine green are loaded in mitochondria-targeted mesoporous silica nanoparticles to reduce innate oxygen consumption by blocking mitochondrial respiration chain, leading to endogenous mitochondrial ROS burst and imaging-guided photodynamic therapy. This mitochondria-targeted oxidative stress amplifier not only disrupts mitochondrial redox homeostasis and triggers long-term high oxidative stress but also makes tumor more sensitive to hypoxia-resistant photodynamic therapy. The imaging-guided ROS amplifier confirms the feasibility and effectiveness of both in vitro and in vivo anticancer performance, suggesting a promising clinical strategy in hypoxia-related tumor treatment.

EDTMP ligand-enhanced water interactions endowing iron oxide nanoparticles with dual-modal MRI contrast ability.

Single-modal magnetic resonance imaging (MRI) contrast agents sometimes cause signal confusion in clinical diagnosis. Utilizing ligands to endow iron oxide nanoparticles (IO NPs) with excellent dual-modal MRI contrast efficiency might be an effective strategy to improve diagnostic accuracy. This work presents the development of a special ligand-assisted one-pot approach for the preparation of super-hydrophilic magnetic NPs with excellent water dispersion, biocompatibility and T1-T2 dual-modal contrast enhancement properties. In addition, the strong binding capacity between the ethylenediamine tetramethylenephosphonic acid (EDTMP) ligand and water molecules induced by the presence of abundant hydrogen bonds significantly improves spin-lattice (T1) and spin-spin (T2) imaging of the IO core. After being modified with the EDTMP ligand, the T2 relaxation rate of the IO core is dramatically increased from 71.78 mM-1 s-1 to 452.38 mM-1 s-1, and a moderate T1 relaxation rate (11.61 mM-1 s-1) is observed simultaneously, implying that the NPs with an average size of 9.7 nm may be potential candidates as high-efficiency T1-T2 MRI contrast agents. This fundamental technique of using super-hydrophilicity ligands to endow IO NPs with dual-modal contrast properties without size change and damage in the T2 contrast effect may provide a useful strategy to facilitate the application of magnetic NPs in the field of medical diagnosis.

Possibility of brigatinib-based therapy, or chemotherapy plus anti-angiogenic treatment after resistance of osimertinib harboring EGFR T790M-cis-C797S mutations in lung adenocarcinoma patients.

BACKGROUND: There was no standard treatment for patients who acquired resistance to osimertinib mediated by epidermal growth factor receptor (EGFR) T790M-cis-C797S. The aim of this study was to investigate the association between different therapeutic strategies and survival outcomes among these patients. METHODS: This retrospective cohort study analyzed 46 patients with metastatic lung adenocarcinoma and EGFR T790M-cis-C797S after osimertinib progression from January 1, 2017 to October 31, 2020. Among them, 13 patients received brigatinib-based therapy, 23 patients received chemotherapy in combination of anti-angiogenics or not, and 10 patients received other targeted treatments like dacomtinib, bevacizumab, or a combined therapy of osimertinib and other targeted drugs. RESULTS: Compared to other targeted therapy, brigatinib-based therapy (median progression-free survival [mPFS]: 4.40 vs. 1.63 months, hazard ratio [HR] = 0.39, 95% confidence interval [CI]: 0.21-0.73, p = 0.001) and chemotherapy-based treatment (mPFS: 4.70 vs. 1.63 months, HR = 0.18, 95% CI: 0.06-0.50, p < 0.001) presented a better survival outcome and there was no significant difference between brigatinib-based therapy and chemotherapy-based treatment (mPFS: 4.40 vs. 4.70 months, HR = 1.24, 95% CI: 0.57-2.67, p = 0.58). Chemotherapy combined with anti-angiogenics achieved a better efficacy than only chemotherapy (mPFS: 5.50 vs. 1.03 months, HR = 0.30, 95% CI: 0.11-0.83, p = 0.02). Patients carrying EGFR exon 19 deletion mutation had a longer PFS than those who harboring EGFR exon 21 p.L858R mutation (4.57 vs. 1.03 months, HR = 0.18, 95% CI: 0.06-0.54, p = 0.001), no matter they received brigatinib-based therapy (mPFS: 5.00 vs. 3.23 months, HR = 0.19, 95% CI: 0.01-0.96, p = 0.05) or chemotherapy-based treatment (mPFS: 7.23 vs. 1.03 months, HR = 0.05, 95% CI 0.01-0.49, p < 0.001). CONCLUSION: Brigatinib-based therapy and chemotherapy plus anti-angiogenics could be considered beyond progression from osimertinib therapy. For patients harboring EGFR exon 19 deletion/T790M/cis-C797S mutation, the clinical efficacy was superior to patients harboring EGFR exon 21 p.L858R/T790M/cis-C797S mutation.

Mitochondrial targeted antioxidants, mitoquinone and SKQ1, not vitamin C, mitigate doxorubicin-induced damage in H9c2 myoblast: pretreatment vs. co-treatment.

BACKGROUND: Preconditioning of the heart ameliorates doxorubicin (Dox)-induced cardiotoxicity. We tested whether pretreating cardiomyocytes by mitochondrial-targeted antioxidants, mitoquinone (MitoQ) or SKQ1, would provide better protection against Dox than co-treatment. METHODS: We investigated the dose-response relationship of MitoQ, SKQ1, and vitamin C on Dox-induced damage on H9c2 cardiomyoblasts when drugs were given concurrently with Dox (e.g., co-treatment) or 24 h prior to Dox (e.g., pretreatment). Moreover, their effects on intracellular and mitochondrial oxidative stress were evaluated by 2,7-dichlorofluorescin diacetate and MitoSOX, respectively. RESULTS: Dox (0.5-50 µM, n = 6) dose-dependently reduced cell viability. By contrast, co-treatment of MitoQ (0.05-10 µM, n = 6) and SKQ1 (0.05-10 µM, n = 6), but not vitamin C (1-2000 µM, n = 3), significantly improved cell viability only at intermediate doses (0.5-1 µM). MitoQ (1 µM) and SKQ1 (1 µM) significantly increased cell viability to 1.79 ± 0.12 and 1.59 ± 0.08 relative to Dox alone, respectively (both p < 0.05). Interestingly, when given as pretreatment, only higher doses of MitoQ (2.5 µM, n = 9) and SKQ1 (5 µM, n = 7) showed maximal protection and improved cell viability to 2.19 ± 0.13 and 1.65 ± 0.07 relative to Dox alone, respectively (both p < 0.01), which was better than that of co-treatment. Moreover, the protective effects were attributed to the significant reduction in Dox-induced intracellular and mitochondrial oxidative stress. CONCLUSION: The data suggest that MitoQ and SKQ1, but not vitamin C, mitigated DOX-induced damage. Moreover, MitoQ pretreatment showed significantly higher cardioprotection than its co-treatment and SKQ1, which may be due to its better antioxidant effects.

Impact of dietary exposure to low-dose tris(1,3-dichloro-2-propyl)phosphate in allergic asthmatic mice.

OBJECTIVE: Tris(1,3-dichloro-2-propyl)phosphate (TDCIPP) is an organophosphorus flame retardant that is an alternative to brominated flame retardants. Although TDCIPP can adversely affect human health, information about its effects on immune and allergic responses is scarce. We aimed to investigate the effects of dietary exposure to TDCIPP using less than the human tolerable daily intake (TDI) in allergic asthmatic mice. METHODS: Male C3H/HeJSlc mice were fed a chow diet containing TDCIPP equivalent to 0.02 µg/kg/day (low; L), 0.2 µg/kg/day (medium; M), or 2 µg/kg/day (high; H) and were intratracheally administered ovalbumin (OVA, 1 µg/animal) every 2 weeks from 5 to 11 weeks of age. RESULTS: In OVA-treated mice, TDCIPP-H exposure tended to enhance pulmonary inflammation compared with vehicle exposure. TDCIPP dose-dependently decreased mRNA level of G protein-coupled estrogen receptor (GPER) in the lungs with or without OVA. OVA + TDCIPP-H treatment tended to increase the total cell number and promoted CD4+ cell activation compared with OVA alone treatment in mediastinal lymph nodes. In splenocytes, an increase in the fraction of Breg cells, but not of total B and T cells, and an increase in IL-5 in cell culture supernatants following OVA re-stimulation in OVA + TDCIPP-H-treated mice was observed compared with OVA-alone-treated mice. Moreover, OVA + TDCIPP-H exposure decreased Gr-1 expression in bone marrow (BM) cells. DISCUSSION: These results suggested that dietary exposure to TDCIPP at TDI level slightly enhances allergic diseases, such as allergic asthma, via GPER regulation at inflamed sites and secondary lymphoid tissue and BM cell alternations.

The Slow-Releasing and Mitochondria-Targeted Hydrogen Sulfide (H2S) Delivery Molecule AP39 Induces Brain Tolerance to Ischemia.

Ischemic stroke is the third leading cause of death in the world, which accounts for almost 12% of the total deaths worldwide. Despite decades of research, the available and effective pharmacotherapy is limited. Some evidence underlines the beneficial properties of hydrogen sulfide (H2S) donors, such as NaSH, in an animal model of brain ischemia and in in vitro research; however, these data are ambiguous. This study was undertaken to verify the neuroprotective activity of AP39, a slow-releasing mitochondria-targeted H2S delivery molecule. We administered AP39 for 7 days prior to ischemia onset, and the potential to induce brain tolerance to ischemia was verified. To do this, we used the rat model of 90-min middle cerebral artery occlusion (MCAO) and used LC-MS/MS, RT-PCR, LuminexTM assays, Western blot and immunofluorescent double-staining to determine the absolute H2S levels, inflammatory markers, neurotrophic factor signaling pathways and apoptosis marker in the ipsilateral frontal cortex, hippocampus and in the dorsal striatum 24 h after ischemia onset. AP39 (50 nmol/kg) reduced the infarct volume, neurological deficit and reduced the microglia marker (Iba1) expression. AP39 also exerted prominent anti-inflammatory activity in reducing the release of Il-1ß, Il-6 and TNFα in brain areas particularly affected by ischemia. Furthermore, AP39 enhanced the pro-survival pathways of neurotrophic factors BDNF-TrkB and NGF-TrkA and reduced the proapoptotic proNGF-p75NTR-sortilin pathway activity. These changes corresponded with reduced levels of cleaved caspase 3. Altogether, AP39 treatment induced adaptative changes within the brain and, by that, developed brain tolerance to ischemia.

Systemic delivery of a mitochondria targeted antioxidant partially preserves limb muscle mass and grip strength in response to androgen deprivation.

Muscle mass is important for health. Decreased testicular androgen production (hypogonadism) contributes to the loss of muscle mass, with loss of limb muscle being particularly debilitating. Androgen replacement is the only pharmacological treatment, which may not be feasible for everyone. Prior work showed that markers of reactive oxygen species and markers of mitochondrial degradation pathways were higher in the limb muscle following castration. Therefore, we tested whether an antioxidant preserved limb muscle mass in male mice subjected to a castration surgery. Subsets of castrated mice were treated with resveratrol (a general antioxidant) or MitoQ (a mitochondria targeted antioxidant). Relative to the non-castrated control mice, lean mass, limb muscle mass, and grip strength were partially preserved only in castrated mice treated with MitoQ. Independent of treatment, markers of mitochondrial degradation pathways remained elevated in all castrated mice. Therefore, a mitochondrial targeted antioxidant may partially preserve limb muscle mass in response to hypogonadism.

Phospho-Sulindac (OXT-328) Inhibits Dry Eye Disease in Rabbits: A Dose-, Formulation- and Structure-Dependent Effect.

Purpose: Inflammation of the ocular surface is central to dry eye disease (DED). The anti-inflammatory agent phospho-sulindac (PS) at a high dose was efficacious against DED in a rabbit model. We assessed the dose, formulation and structure dependence of PS's effect. Methods: In rabbits with concanavalin A-induced DED we evaluated a range of PS concentrations (0.05%-1.6%) and dosing frequencies, assessed the duration of its effect with PS in 2 solution formulations and one emulsion formulation, and compared the efficacy of PS to that of sulindac, and of the structurally similar phospho-ibuprofen amide. We determined tear breakup time (TBUT) (tear stability), Schirmer's tear test (tear production), and by esthesiometry corneal sensitivity (symptoms). We also determined the biodistribution in the eye of topically applied PS. Results: PS in a solution formulation, given as eye drops q.i.d. was efficacious starting at a dose of 0.1%. The effect was apparent after 2 days of treatment and lasted at least 8 days after the last dose. Both signs (evidenced by TBUT and Schirmer's test) and symptoms (measured by corneal sensitivity) improved significantly. The best formulation was the solution formulation; a cyclodextrin-based formulation was also successful but the emulsion formulation was not. PS and its metabolites were essentially restricted to the anterior chamber of the eye. Sulindac and phospho-ibuprofen amide had no efficacy on DED. Conclusions: PS is efficacious against DED. Its effect, encompassing signs, and symptoms, are dose, formulation, and structure dependent. PS has therapeutic promise and merits further development.

Effect of Protein Corona on Mitochondrial Targeting Ability and Cytotoxicity of Triphenylphosphonium Conjugated with Polyglycerol-Functionalized Nanodiamond.

Functionalization of nanoparticles (NPs) with targeting moieties has a high potential to advance precision nanomedicine. However, the targeting moieties on a NP surface are known to be masked by a protein corona in biofluids, lowering the targeting efficiency. Although it has been demonstrated at the cellular level, little is known about the influence of the protein corona on the subcellular targeting. Herein, we adopted triphenylphosphonium (TPP) as a mitochondrial targeting moiety and investigated the effects of protein coronas from fetal bovine serum and human plasma on its targeting ability and cytotoxicity. Specifically, we introduced TPP in low (l) and high (h) densities on the surface of nanodiamond (ND) functionalized with polyglycerol (PG). Despite the "corona-free" PG interface, we found that the TPP moiety attracted proteins to form a corona layer with clear linearity between the TPP density and the protein amount. By performing investigations on human cervix epithelium (HeLa) and human lung epithelial carcinoma (A549) cells, we further demonstrated that (1) the protein corona alleviated the cytotoxicity of both ND-PG-TPP-l and -h, (2) a smaller amount of proteins on the surface of ND-PG-TPP-l did not affect its mitochondrial targeting ability, and (3) a larger amount of proteins on the surface of ND-PG-TPP-h diminished its targeting specificity by restricting the NDs inside the endosome and lysosome compartments. Our findings will provide in-depth insights into the design of NPs with active targeting moiety for more precise and safer delivery at the subcellular level.