Mitochondrial-Targeted Metal-Phenolic Nanoparticles to Attenuate Intervertebral Disc Degeneration: Alleviating Oxidative Stress and Mitochondrial Dysfunction.

As intervertebral disc degeneration (IVDD) proceeds, the dysfunctional mitochondria disrupt the viability of nucleus pulposus cells, initiating the degradation of the extracellular matrix. To date, there is a lack of effective therapies targeting the mitochondria of nucleus pulposus cells. Here, we synthesized polygallic acid-manganese (PGA-Mn) nanoparticles via self-assembly polymerization of gallic acid in an aqueous medium and introduced a mitochondrial targeting peptide (TP04) onto the nanoparticles using a Schiff base linkage, resulting in PGA-Mn-TP04 nanoparticles. With a size smaller than 50 nm, PGA-Mn-TP04 possesses pH-buffering capacity, avoiding lysosomal confinement and selectively accumulating within mitochondria through electrostatic interactions. The rapid electron exchange between manganese ions and gallic acid enhances the redox capability of PGA-Mn-TP04, effectively reducing mitochondrial damage caused by mitochondrial reactive oxygen species. Moreover, PGA-Mn-TP04 restores mitochondrial function by facilitating the fusion of mitochondria and minimizing their fission, thereby sustaining the vitality of nucleus pulposus cells. In the rat IVDD model, PGA-Mn-TP04 maintained intervertebral disc height and nucleus pulposus tissue hydration. It offers a nonoperative treatment approach for IVDD and other skeletal muscle diseases resulting from mitochondrial dysfunction, presenting an alternative to traditional surgical interventions.

Combined Photosensitive Gene Therapy Effective Against Triple-Negative Breast Cancer in Mice Model.

Introduction: Tumor hypoxia and invasion present significant challenges for the efficacy of photodynamic therapy (PDT) in triple-negative breast cancer (TNBC). This study developed a mitochondrial targeting strategy that combined PDT and gene therapy to promote each other and address the challenges. Methods: The positively charged amphiphilic material triphenylphosphine-tocopherol polyethylene glycol succinate (TPP-TPGS, TPS) and the photosensitizer chloride e6 (Ce6) formed TPS@Ce6 nanoparticles (NPs) by hydrophobic interaction. They electrostatically condensed microRNA-34a (miR-34a) to form stable TPS@Ce6/miRNA NPs. Results: Firstly, Ce6 disrupted the lysosomal membrane, followed by successful delivery of miR-34a by TPS@Ce6/miRNA NPs. Meanwhile, miR-34a reduced ROS depletion and further enhanced the effectiveness of PDT. Consequently, the mutual promotion between PDT and gene therapy led to enhanced anti-tumor effects. Furthermore, the TPS@Ce6/miRNA NPs promoted apoptosis by down-regulating Caspase-3 and inhibited tumor cell migration and invasion by down-regulating N-Cadherin. In addition, in vitro and in vivo experiments demonstrated that the TPS@Ce6/miRNA NPs achieved excellent anti-tumor effects. These findings highlighted the enhanced anticancer effects and reduced migration of tumor cells through the synergistic effects of PDT and gene therapy. Conclusion: Taken together, the targeted co-delivery of Ce6 and miR-34a will facilitate the application of photodynamic and genic nanomedicine in the treatment of aggressive tumors, particularly TNBC.

Development and Evaluation/Verification of a Fully Automated Test Platform for the Rapid Detection of Cyclospora cayetanensis in Produce Matrices.

Cyclosporiasis, caused by the coccidian parasite Cyclospora cayetanensis, has emerged as an increasing global public health concern, with the incidence of laboratory-confirmed domestically acquired cases in the US exceeding 10,000 since 2018. A recently published qPCR assay (Mit1C) based on a mitochondrial target gene showed high specificity and good sensitivity for the detection of C. cayetanensis in fresh produce. The present study shows the integration and verification of the same mitochondrial target into a fully automated and streamlined platform that performs DNA isolation, PCR, hybridization, results visualization, and reporting of results to simplify and reduce hands-on time for the detection of this parasite. By using the same primer sets for both the target of interest (i.e., Mit1C) and the internal assay control (IAC), we were able to rapidly migrate the previously developed Mit1C qPCR assay into the more streamlined and automated format Rheonix C. cayetanensisTM Assay. Once the best conditions for detection were optimized and the migration to the fully automated format was completed, we compared the performance of the automated platform against the original "bench top" Mit1C qPCR assay. The automated Rheonix C. cayetanensis Assay achieved equivalent performance characteristics as the original assay, including the same performance for both inclusion and exclusion panels, and it was able to detect as low as 5 C. cayetanensis oocysts in fresh produce while significantly reducing hands-on time. We expect that the streamlined assay can be used as a tool for outbreak and/or surveillance activities to detect the presence of C. cayetanensis in produce samples.

Insulin sensitizers in 2023: lessons learned and new avenues for investigation.

INTRODUCTION: 'Insulin sensitizers' derived discoveries of the Takeda Company in 1970s. Pioglitazone remains the best in class with beneficial pleiotropic pharmacology, although use is limited by tolerability issues. Various attempts to expand out of this class assumed the primary molecular target was the transcription factor, PPARγ. Findings over the last 10 years have identified new targets of thiazolidinediones (TZDs) that should alter the drug discovery paradigm. AREAS COVERED: We review structural classes of experimental insulin sensitizer drugs, some of which have attained limited approval in some markets. The TZD pioglitazone, originally approved in 1999 as a secondary treatment for type 2 diabetes, has demonstrated benefit in apparently diverse spectrums of disease from cardiovascular to neurological issues. New TZDs modulate a newly identified mitochondrial target (the mitochondrial pyruvate carrier) to reprogram metabolism and produce insulin sensitizing pharmacology devoid of tolerability issues. EXPERT OPINION: Greater understanding of the mechanism of action of insulin sensitizing drugs can expand the rationale for the fields of treatment and potential for treatment combinations. This understanding can facilitate the registration and broader use of agents with that impact the pathophysiology that underlies chronic metabolic diseases as well as host responses to environmental insults including pathogens, insulin sensitizer, MPC, mitochondrial target, metabolic reprogramming, chronic and infectious disease.

Formulation and evaluation of a two-stage targeted liposome coated with hyaluronic acid for improving lung cancer chemotherapy and overcoming multidrug resistance.

Multidrug resistance (MDR) has emerged as a prominent challenge contributing to the ineffectiveness of chemotherapy in treating non-small cell lung cancer (NSCLC) patients. Currently, mitochondria of cancer cells are identified as a promising target for overcoming MDR due to their crucial role in intrinsic apoptosis pathway and energy supply centers. Here, a two-stage targeted liposome (HA/TT LP/PTX) was successfully developed via a two-step process: PTX-loaded cationic liposome (TT LP/PTX) were formulated by lipid film hydration & ultrasound technique, followed by further coating with natural anionic polysaccharide hyaluronic acid (HA). TT, an amphipathic polymer conjugate of triphenylphosphine (TPP)-tocopheryl polyethylene glycol succinate (TPGS), was used to modify the liposomes for mitochondrial targeting. The average particle size, zeta potential and encapsulation efficiency (EE%) of HA/TT LP/PTX were found to be 153 nm, -30.3 mV and 92.1% based on the optimal prescription of HA/TT LP/PTX. Compared to cationic liposome, HA-coated liposomes showed improved stability and safety, including biological stability in serum, cytocompatibility, and lower hemolysis percentage. In drug-resistant A549/T cells, HA was shown to improve the cellular uptake of PTX through CD44 receptor-mediated endocytosis and subsequent degradation by hyaluronidase (HAase) in endosomes. Following this, the exposure of TT polymer facilitated the accumulation of PTX within the mitochondria. As a result, the function of mitochondria in A549/T cells was disturbed, leading to an increased ROS level, decreased ATP level, dissipated MMP, and increased G2/M phase arrest. This resulted in a higher apoptotic rate and stronger anticancer efficacy.

Global miRNA expression reveals novel nuclear and mitochondrial interactions in Type 1 diabetes mellitus.

Background: Considering the potential role of miRNAs as biomarkers and their interaction with both nuclear and mitochondrial genes, we investigated the miRNA expression profile in type 1 diabetes (T1DM) patients, including the pathways in which they are involved considering both nuclear and mitochondrial functions. Methods: We analyzed samples of T1DM patients and control individuals (normal glucose tolerance) by high throughput miRNA sequencing (miRNome). Next, five miRNAs - hsa-miR-26b-5p, hsa-let-7i-5p, hsa-miR-143-3p, hsa-miR-501-3p and hsa-miR-100-5p - were validated by RT-qPCR. The identification of target genes was extracted from miRTarBase and mitoXplorer database. We also performed receiver operating characteristic (ROC) curves and miRNAs that had an AUC > 0.85 were considered potential biomarkers. Results: Overall, 41 miRNAs were differentially expressed in T1DM patients compared to control. Hsa-miR-21-5p had the highest number of predicted target genes and was associated with several pathways, including insulin signaling and apoptosis. 34.1% (14/41) of the differentially expressed miRNAs also targeted mitochondrial genes, and 80.5% (33/41) of them targeted nuclear genes involved in the mitochondrial metabolism. All five validated miRNAs were upregulated in T1DM. Among them, hsa-miR-26b-5p showed AUC>0.85, being suggested as potential biomarker to T1DM. Conclusion: Our results demonstrated 41 DE miRNAs that had a great accuracy in discriminating T1DM and control group. Furthermore, we demonstrate the influence of these miRNAs on numerous metabolic pathways, including mitochondrial metabolism. Hsa-miR-26b-5p and hsa-miR-21-5p were highlighted in our results, possibly acting on nuclear and mitochondrial dysfunction and, subsequently, T1DM dysregulation.

Current status of iridium-based complexes against lung cancer.

Lung cancer is one of the most common malignant tumors, with the highest mortality rate in the world, and its incidence is second only to breast cancer. It has posed a serious threat to human health. Cisplatin, a metal-based drug, is one of the most widely used chemotherapeutic agents for the treatment of various cancers. However, its clinical efficacy is seriously limited by numerous side effects and drug resistance. This has led to the exploration and development of other transition metal complexes for the treatment of malignant tumors. In recent years, iridium-based complexes have attracted extensive attention due to their potent anticancer activities, limited side effects, unique antitumor mechanisms, and rich optical properties, and are expected to be potential antitumor drugs. In this review, we summarize the recent progress of iridium complexes against lung cancer and introduce their anti-tumor mechanisms, including apoptosis, cycle arrest, inhibition of lung cancer cell migration, induction of immunogenic cell death, etc.

Mitochondrial targeted drug delivery combined with manganese catalyzed Fenton reaction for the treatment of breast cancer.

In previous studies, we found that triphenylphosphine-modified doxorubicin (TPP-DOX) can effectively kill drug-resistant tumor cells, but its effect on sensitive tumor cells is weakened. In this research, with albumin from Bovine Serum (BSA) as a carrier, TPP-DOX@MnBSA (TD@MB) nanoparticles were prepared by co-loading TPP-DOX and manganese which can realize the combination of chemotherapy and chemodynamic therapy (CDT). The uniform and stable nano-spherical nanoparticle can promote drug uptake, achieve mitochondrial-targeted drug delivery, increase intracellular reactive oxygen species (ROS) and catalyze the production of highly toxic oxidative hydroxyl radicals (OH·), further inhibiting the growth of both sensitive and drug-resistant MCF-7 cells. Besides, TD@MB can down-regulate the stemness-related proteins and the metastasis-related proteins, potentially decreasing the tumor stemness and metastasis. In vivo experiment indicated that TD@MB was able to exert desired antitumor effect, good tumor targeting and biocompatibility.

Development of a mito-CRISPR system for generating mitochondrial DNA-deleted strain in Saccharomyces cerevisiae.

Mitochondrial dysfunction can occur in a variety of ways, most often due to the deletion or mutation of mitochondrial DNA (mtDNA). The easy generation of yeasts with mtDNA deletion is attractive for analyzing the functions of the mtDNA gene. Treatment of yeasts with ethidium bromide is a well-known method for generating ρ° cells with complete deletion of mtDNA from Saccharomyces cerevisiae. However, the mutagenic effects of ethidium bromide on the nuclear genome cannot be excluded. In this study, we developed a "mito-CRISPR system" that specifically generates ρ° cells of yeasts. This system enabled the specific cleavage of mtDNA by introducing Cas9 fused with the mitochondrial target sequence at the N-terminus and guide RNA into mitochondria, resulting in the specific generation of ρ° cells in yeasts. The mito-CRISPR system provides a concise technology for deleting mtDNA in yeasts.

Mitochondrial targeted doxorubicin derivatives delivered by ROS-responsive nanocarriers to breast tumor for overcoming of multidrug resistance.

Multidrug resistance (MDR) is a serious challenge in chemotherapy and also a major threat to breast cancer treatment. As an intracellular energy factory, mitochondria provide energy for drug efflux and are deeply involved in multidrug resistance. Mitochondrial targeted delivery of doxorubicin can overcome multidrug resistance by disrupting mitochondrial function. By incorporating a reactive oxygen species (ROS)-responsive hydrophobic group into the backbone structure of hyaluronic acid - a natural ligand for the highly expressed CD44 receptor on tumor surfaces, a novel ROS-responsive and CD44-targeting nano-carriers was constructed. In this study, mitochondria-targeted triphenylphosphine modified-doxorubicin (TPP-DOX) and amphipathic ROS-responsive hyaluronic acid derivatives (HA-PBPE) were synthesized and confirmed by 1H NMR. The nanocarriers TPP-DOX @ HA-PBPE was prepared in a regular shape and particle size of approximately 200 nm. Compared to free DOX, its antitumor activity in vitro and tumor passive targeting in vivo has been enhanced. The ROS-responsive TPP-DOX@HA-PBPE nanocarriers system provide a promising strategy for the reverse of MDR and efficient delivery of doxorubicin derivatives into drug-resistant cancer cells.

Co-targeting of lysosome and mitophagy in cancer stem cells with chloroquine analogues and antibiotics.

The catabolic autophagy eliminates cytoplasmic components and organelles via lysosomes. Non-selective bulk autophagy and selective autophagy (mitophagy) are linked in intracellular homeostasis both normal and cancer cells. Autophagy has complex and paradoxical dual role in cancers; it can play either tumour suppressor or tumour promoter depending on the tumour type, stage, microenvironment and genetic context. Cancer stem cells (CSCs) cause tumour recurrence and promote resistant to therapy for driving poor clinical consequences. Thus, new healing strategies are urgently needed to annihilate and eradicate CSCs. As chloroquine (CQ) analogues show positive clinical outcome in several clinical trials either standalone or combination with several chemotherapies. Moreover, CQ analogues are known to eliminate CSCs via altering DNA methylation. However, several obstacles such as higher concentrations and dose-dependent toxicity are noticeable in the treatment of cancers. As tumour cells predominantly rely on mitochondrial actions, mitochondrial targeting FDA-approved antibiotics are reported to effectively eradicate CSCs alone or combination with chemotherapy. However, antibiotics cause metabolic glycolytic shift in cancer cells for survival and repopulation. This review will provide a sketch of the inhibiting roles of current chloroquine analogues and antibiotic combination in CSC autophagy process and discuss the possibility that pre-clinical and clinical potential therapeutic strategy for anticancer therapy.

Doxorubicin derivative loaded acetal-PEG-PCCL micelles for overcoming multidrug resistance in MCF-7/ADR cells.

Objective: This study was aimed to develop DOX-TPP loaded acetal-PEG-PCCL micelles to improve the clinical efficacy of drug resistance tumor. Significance: Chemotherapy is one of the main treatments for breast cancer but is plagued by multidrug resistance (MDR). DOX-TPP-loaded micelles can enhance the specific concentration of drugs in the tumor and improve the efficacy and overcome MDR. Methods: In this study, DOX-TPP-loaded micelles based on acetal-PEG-PCCL were prepared and their physicochemical properties were characterized. The cellular uptake and ability to induce apoptosis of the micelles was confirmed by flow cytometry in MCF-7/ADR cells. In addition, cytotoxicity of the micelles was studied in MCF-7 cells and MCF-7/ADR cells. Confocal is used to study the subcellular distribution of DOX. Free DOX-TPP or DOX-TPP-loaded acetal-PEG-PCCL micelles were administered via intravenous injection in the tail vain for the biodistribution study in vivo. Results: The diameter of micelles was about 102.4 nm and their drug-loading efficiency is 61.8%. The structural characterization was confirmed by 1H NMR. The micelles exhibited better antitumor efficacy compared to free doxorubicin in MCF-7/ADR cells by MTT assay. The apoptotic rate and the cellular uptake of micelles were significantly higher than free DOX and DOX-TPP. Micelles can efficiently deliver mitochondria-targeting DOX-TPP to tumor cells. The result of bio-distribution showed that the micelles had stronger tumor infiltration ability than free drugs. Conclusions: In this study, mitochondriotropic DOX-TPP was conjugated to the nanocarrier acetal-PEG-PCCL via ionic interaction to form a polymer, which spontaneously formed spherical micelles. The cytotoxicity and cellular uptake of the micelles are superior to free DOX and exhibit mitochondrial targeting and passive tumor targeting, indicating that they have potential prospects.

Mitochondria-targeted delivery of doxorubicin to enhance antitumor activity with HER-2 peptide-mediated multifunctional pH-sensitive DQAsomes.

INTRODUCTION: Multidrug resistance (MDR) of breast cancer is the major challenge to successful chemotherapy while mitochondria-targeting therapy was a promising strategy to overcome MDR. MATERIALS AND METHODS: In this study, HER-2 peptide-PEG2000-Schiff base-cholesterol (HPSC) derivate was synthesized successfully and incorporated it on the surface of the doxorubicin (DOX)-loaded dequalinium (DQA) chloride vesicle (HPS-DQAsomes) to treat drug-resistant breast cancer. Evaluations were performed using human breast cancer cell and DOX-resistant breast cancer cell lines (MCF-7 and MCF-7/ADR). RESULTS: The particle size of HPS-DQAsomes was ~110 nm with spherical shape. In vitro cytotoxicity assay indicated that HPS-DQAsomes could increase the cytotoxicity against MCF-7/ADR cell line. Cellular uptake and mitochondria-targeting assay demonstrated that HPS-DQAsomes could target delivering therapeutical agent to mitochondria and inducing mitochondria-driven apoptosis process. In vivo antitumor assay suggested that HPS-DQAsomes could reach favorable antitumor activity due to both tumor targetability and sub-organelles' targetability. Histological assay also indicated that HPS-DQAsomes showed a strong apoptosis-inducing effect. No obvious systematic toxicity of HPS-DQAsomes could be observed. CONCLUSION: In summary, multifunctional HPS-DQAsomes provide a novel and versatile approach for overcoming MDR via mitochondrial pathway in cancer treatment.

Delivery of mitochondriotropic doxorubicin derivatives using self-assembling hyaluronic acid nanocarriers in doxorubicin-resistant breast cancer.

Breast cancer is the leading cause of cancer-related death for women, and multidrug resistance (MDR) is the major obstacle faced by chemotherapy for breast cancer. We have previously synthesized a doxorubicin (DOX) derivative by conjugating DOX with triphenylphosphonium (TPP) to achieve mitochondrial delivery, which induced higher cytotoxicity in drug-resistant breast cancer cells than DOX itself. Due to its amphiphilicity, TPP-DOX is difficult to physically entrap in nanocarriers. Thus, we linked it to hyaluronic acid (HA) by a novel ionic bond utilizing the specific bromide ion of TPP to form supra-molecular self-assembled structures (HA-ionic-TPP-DOX). The product was analyzed uisng 1H-NMR, 13C-NMR and mass spectrometry. The HA nanocarriers (HA-ionic-TPP-DOX) were shown to self-assemble into spherical nanoparticles, and sensitive to acidic pH in terms of morphology and drug release. Compared with free DOX, HA-ionic-TPP-DOX produced much greater intracellular DOX accumulation and mitochondrial localization, leading to increased ROS production, slightly decreased mitochondrial membrane potential, increased cytotoxicity in MCF-7/ADR cells and enhanced tumor targeting in vivo. In xenotransplant zebrafish model with the MCF-7/ADR cell line, both TPP-DOX and HA-ionic-TPP-DOX inhibited tumor cell proliferation without inducing significant side effects compared with free DOX. In addition, we observed a better anti-tumor effect of HA-ionic-TPP-DOX on MCF-7/ADR cells in zebrafish than that of TPP-DOX treatment. Furthermore, HA-ionic-DOX-TPP exhibited favorable biocompatibility and anti-tumor effects in MCF-7/ADR tumor-bearing nude mice in comparison with the effects of TPP-DOX and DOX, suggesting the potential of HA-ionic-TPP-DOX for the targeted delivery and controlled release of TPP-DOX, which can lead to the sensitization of resistant breast tumors.

Flavonoids and mitochondrial pharmacology: A new paradigm for cardioprotection.

Acute myocardial ischemia is one of the major causes of illness and of deaths in Western society; therefore the definition of the signaling pathways involved in the cardioprotection represents a challenging goal in order to discover novel pharmacological approaches. In this regard, a number of epidemiologic studies demonstrate a relationship between intake of flavonoid-rich foods and reduction of cardiovascular risk factors and mortality. Moreover, numerous experimental studies have examined flavonoid-induced cardioprotective effects on several animal models of myocardial ischemia/reperfusion. As concerns the mechanisms of action, although the antioxidant effect of flavonoids has been long thought to be a crucial factor accounting for cardioprotection, mitochondrial pathways (ion channels, protein kinases, etc.) are presently emerging as specific pharmacological targets more relevantly involved in the anti-ischemic effects of some flavonoids. Since these pharmacodynamic features seem to be poorly considered, this review examines the mitochondrial role in the cardioprotective mechanisms of some members of this phytochemical class, by describing the biological pathways and reporting an overview of the most important experimental evidence in this field.