Nanotechnology inspired tools for mitochondrial dysfunction related diseases

Extracellular vesicles: opening up a new perspective for the diagnosis and treatment of mitochondrial dysfunction

Mitochondria are crucial organelles responsible for energy generation in eukaryotic cells. Oxidative stress, calcium disorders, and mitochondrial DNA abnormalities can all cause mitochondrial dysfunction. It is now well documented that mitochondrial dysfunction significantly contributes to the pathogenesis of numerous illnesses. Hence, it is vital to investigate innovative treatment methods targeting mitochondrial dysfunction. Extracellular vesicles (EVs) are cell-derived nanovesicles that serve as intercellular messengers and are classified into small EVs (sEVs, < 200 nm) and large EVs (lEVs, > 200 nm) based on their sizes. It is worth noting that certain subtypes of EVs are rich in mitochondrial components (even structurally intact mitochondria) and possess the ability to transfer them or other contents including proteins and nucleic acids to recipient cells to modulate their mitochondrial function. Specifically, EVs can modulate target cell mitochondrial homeostasis as well as mitochondria-controlled apoptosis and ROS generation by delivering relevant substances. In addition, the artificial modification of EVs as delivery carriers for therapeutic goods targeting mitochondria is also a current research hotspot. In this article, we will focus on the ability of EVs to modulate the mitochondrial function of target cells, aiming to offer novel perspectives on therapeutic approaches for diverse conditions linked to mitochondrial dysfunction.

Mitochondrial endogenous substance transport-inspired nanomaterials for mitochondria-targeted gene delivery

Mitochondrial genome (mtDNA) independent of nuclear gene is a set of double-stranded circular DNA that encodes 13 proteins, 2 ribosomal RNAs and 22 mitochondrial transfer RNAs, all of which play vital roles in functions as well as behaviors of mitochondria. Mutations in mtDNA result in various mitochondrial disorders without available cures. However, the manipulation of mtDNA via the mitochondria-targeted gene delivery faces formidable barriers, particularly owing to the mitochondrial double membrane. Given the fact that there are various transport channels on the mitochondrial membrane used to transfer a variety of endogenous substances to maintain the normal functions of mitochondria, mitochondrial endogenous substance transport-inspired nanomaterials have been proposed for mitochondria-targeted gene delivery. In this review, we summarize mitochondria-targeted gene delivery systems based on different mitochondrial endogenous substance transport pathways. These are categorized into mitochondrial steroid hormones import pathways-inspired nanomaterials, protein import pathways-inspired nanomaterials and other mitochondria-targeted gene delivery nanomaterials. We also review the applications and challenges involved in current mitochondrial gene editing systems. This review delves into the approaches of mitochondria-targeted gene delivery, providing details on the design of mitochondria-targeted delivery systems and the limitations regarding the various technologies. Despite the progress in this field is currently slow, the ongoing exploration of mitochondrial endogenous substance transport and mitochondrial biological phenomena may act as a crucial breakthrough in the targeted delivery of gene into mitochondria and even the manipulation of mtDNA.

Stemness, invasion, and immunosuppression modulation in recurrent glioblastoma using nanotherapy

The recurrent nature of glioblastoma negatively impacts conventional treatment strategies leading to a growing need for nanomedicine. Nanotherapeutics, an approach designed to deliver drugs to specific sites, is experiencing rapid growth and gaining immense popularity. Having potential in reaching the hard-to-reach disease sites, this field has the potential to show high efficacy in combatting glioblastoma progression. The presence of glioblastoma stem cells (GSCs) is a major factor behind the poor prognosis of glioblastoma multiforme (GBM). Stemness potential, heterogeneity, and self-renewal capacity, are some of the properties that make GSCs invade across the distant regions of the brain. Despite advances in medical technology and MRI-guided maximal surgical resection, not all GSCs residing in the brain can be removed, leading to recurrent disease. The aggressiveness of GBM is often correlated with immune suppression, where the T-cells are unable to infiltrate the cancer initiating GSCs. Standard of care therapies, including surgery and chemotherapy in combination with radiation therapy, have failed to tackle all the challenges of the GSCs, making it increasingly important for researchers to develop strategies to tackle their growth and proliferation and reduce the recurrence of GBM. Here, we will focus on the advancements in the field of nanomedicine that has the potential to show positive impact in managing glioblastoma tumor microenvironment. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.

Strategic disruption of cancer's powerhouse: precise nanomedicine targeting of mitochondrial metabolism

Mitochondria occupy a central role in the biology of most eukaryotic cells, functioning as the hub of oxidative metabolism where sugars, fats, and amino acids are ultimately oxidized to release energy. This crucial function fuels a variety of cellular activities. Disruption in mitochondrial metabolism is a common feature in many diseases, including cancer, neurodegenerative conditions and cardiovascular diseases. Targeting tumor cell mitochondrial metabolism with multifunctional nanosystems emerges as a promising strategy for enhancing therapeutic efficacy against cancer. This review comprehensively outlines the pathways of mitochondrial metabolism, emphasizing their critical roles in cellular energy production and metabolic regulation. The associations between aberrant mitochondrial metabolism and the initiation and progression of cancer are highlighted, illustrating how these metabolic disruptions contribute to oncogenesis and tumor sustainability. More importantly, innovative strategies employing nanomedicines to precisely target mitochondrial metabolic pathways in cancer therapy are fully explored. Furthermore, key challenges and future directions in this field are identified and discussed. Collectively, this review provides a comprehensive understanding of the current state and future potential of nanomedicine in targeting mitochondrial metabolism, offering insights for developing more effective cancer therapies.

Current Progress in the Science of Novel Adjuvant Nano-Vaccine-Induced Protective Immune Responses

Vaccinations are vital as they protect us from various illness-causing agents. Despite all the advancements in vaccine-related research, developing improved and safer vaccines against devastating infectious diseases including Ebola, tuberculosis and acquired immune deficiency syndrome (AIDS) remains a significant challenge. In addition, some of the current human vaccines can cause adverse reactions in some individuals, which limits their use for massive vaccination program. Therefore, it is necessary to design optimal vaccine candidates that can elicit appropriate immune responses but do not induce side effects. Subunit vaccines are relatively safe for the vaccination of humans, but they are unable to trigger an optimal protective immune response without an adjuvant. Although different types of adjuvants have been used for the formulation of vaccines to fight pathogens that have high antigenic diversity, due to the toxicity and safety issues associated with human-specific adjuvants, there are only a few adjuvants that have been approved for the formulation of human vaccines. Recently, nanoparticles (NPs) have gain specific attention and are commonly used as adjuvants for vaccine development as well as for drug delivery due to their excellent immune modulation properties. This review will focus on the current state of adjuvants in vaccine development, the mechanisms of human-compatible adjuvants and future research directions. We hope this review will provide valuable information to discovery novel adjuvants and drug delivery systems for developing novel vaccines and treatments.

Synthesis of Triphenylphosphonium-Linked Derivative of 3,5-Ditert-butyl-4-hydroxybenzylidene-malononitrile (SF6847) via Knoevenagel Reaction Yields an Effective Mitochondria-Targeted Protonophoric Uncoupler

Mitochondrial uncouplers are actively sought as potential therapeutics. Here, we report the first successful synthesis of mitochondria-targeted derivatives of the highly potent uncoupler 3,5-ditert-butyl-4-hydroxybenzylidene-malononitrile (SF6847), bearing a cationic alkyl(triphenyl)phosphonium (TPP) group. As a key step of the synthesis, we used condensation of a ketophenol with malononitrile via the Knoevenagel reaction. SF-C5-TPP with a pentamethylene linker between SF6847 and TPP, stimulating respiration and collapsing membrane potential of rat liver mitochondria at submicromolar concentrations, proved to be the most effective uncoupler of the series. SF-C5-TPP showed pronounced protonophoric activity on a model planar bilayer lipid membrane. Importantly, SF-C5-TPP exhibited rather low toxicity in fibroblast cell culture, causing mitochondrial depolarization in cells at concentrations that only slightly affected cell viability. SF-C5-TPP was more effective in decreasing the mitochondrial membrane potential in the cell culture than SF6847, in contrast to the case of isolated mitochondria. Like other zwitterionic uncouplers, SF-C5-TPP inhibited the growth of Bacillus subtilis in the micromolar concentration range.

A Holistic Perspective on Living Aggregate

Aggregate is one of the most extensive existing modes of matters in the world. Besides the research objectives of inanimate systems in physical science, the entities in life science can be regarded as living aggregates, which are far from being thoroughly understood despite the great advances in molecular biology. Molecular biology follows the research philosophy of reductionism, which generally reduces the whole into parts to study. Although reductionism benefits the understanding of molecular behaviors, it encounters limitations when extending to the aggregate level. Holism is another epistemology comparable to reductionism, which studies objectives at the aggregate level, emphasizing the interactions and synergetic/antagonistic effects of a group of composed single entities in determining the characteristics of a whole. As a representative of holism, aggregation-induced emission (AIE) materials have made great achievements in the past two decades in both physical and life science. In particular, the unique properties of AIE materials endow them with in situ and real-time visual methods to investigate the inconsistency between microscopic molecules and macroscopic substances, offering researchers excellent toolkits to study living aggregates. The applications of AIE materials in life science are still in their infancy and worth expanding. In this Perspective, we summarize the research progress of AIE materials in unveiling some phenomena and processes of living systems, aiming to provide a general research approach from the viewpoint of holism. At last, insights into what we can do in the near future are also raised and discussed.

Overcoming biological barriers BBB/BBTB by designing PUFA functionalised lipid-based nanocarriers for glioblastoma targeted therapy

A major obstacle for chemotherapeutics in Glioblastoma (GB) is to reach the tumour cells due to the presence of the blood-brain barrier (BBB) and chemoresistance of anticancer drugs. The present study reports two polyunsaturated fatty acids, gamma-linolenic acid (GLA) and alpha-linolenic acid (ALA) appended nanostructured lipid carriers (NLCs) of a CNS negative chemotherapeutic drug docetaxel (DTX) for targeted delivery to GB. The ligand appended DTX-NLCs demonstrated particle size < 160 nm, PDI < 0.29 and a negative surface charge. The successful linkage of GLA (41 %) and ALA (30 %) ligand conjugation to DTX- NLCs was confirmed by diminished surface amino groups on the NLCs, lower surface charge and FTIR profiling. Fluorophore labelled GLA-DTX-NLCs and ALA-DTX-NLCs permeated the in-vitro 3D BBB model with Papp values of 1.8 × 10-3 and 1.9 × 10-3 cm/s respectively. Following permeation, both formulations showed enhanced uptake by GB immortalised cells while ALA-DTX-NLCs showed higher uptake in patient-derived GB cells as evidenced in an in-vitro 3D blood brain tumour barrier (BBTB) model. Both surface functionalised formulations showed higher internalisation in GB cells as compared to bare DTX-NLCs. ALA-DTX-NLCs and GLA-DTX-NLCs showed 13.9-fold and 6.8-fold higher DTX activity respectively at 24 h as indicated by IC50 values when tested in patient-derived GB cells. ALA-DTX-NLCs displayed better efficacy than GLA-DTX-NLCs when tested against 3D tumour spheroids and patient-derived cells. These novel formulations will contribute widely to overcoming biological barriers for treating glioblastoma.

Current Advances in Nanotheranostics for Molecular Imaging and Therapy of Cardiovascular Disorders

Cardiovascular diseases (CVDs) refer to a collection of conditions characterized by abnormalities in the cardiovascular system. They are a global problem and one of the leading causes of mortality and disability. Nanotheranostics implies to the combination of diagnostic and therapeutic capabilities inside a single nanoscale platform that has allowed for significant advancement in cardiovascular diagnosis and therapy. These advancements are being developed to improve imaging capabilities, introduce personalized therapies, and boost cardiovascular disease patient treatment outcomes. Significant progress has been achieved in the integration of imaging and therapeutic capabilities within nanocarriers. In the case of cardiovascular disease, nanoparticles provide targeted delivery of therapeutics, genetic material, photothermal, and imaging agents. Directing and monitoring the movement of these therapeutic nanoparticles may be done with pinpoint accuracy by using imaging modalities such as cardiovascular magnetic resonance (CMR), computed tomography (CT), positron emission tomography (PET), photoacoustic/ultrasound, and fluorescence imaging. Recently, there has been an increasing demand of noninvasive for multimodal nanotheranostic platforms. In these platforms, various imaging technologies such as optical and magnetic resonance are integrated into a single nanoparticle. This platform helps in acquiring more accurate descriptions of cardiovascular diseases and provides clues for accurate diagnosis. Advances in surface functionalization methods have strengthened the potential application of nanotheranostics in cardiovascular diagnosis and therapy. In this Review, we have covered the potential impact of nanomedicine on CVDs. Additionally, we have discussed the recently developed various nanoparticles for CVDs imaging. Moreover, advancements in the CMR, CT, PET, ultrasound, and photoacoustic imaging for the CVDs have been discussed. We have limited our discussion to nanomaterials based clinical trials for CVDs and their patents.

Nanovesicular-Mediated Intranasal Drug Therapy for Neurodegenerative Disease

Numerous neurodegenerative conditions, such as Alzheimer's, Huntington's, Parkinson's, amyotrophic lateral sclerosis, and glioblastoma multiform are now becoming significant concerns of global health. Formulation-related issues, physiological and anatomical barriers, post-administration obstacles, physical challenges, regulatory limitations, environmental hurdles, and health and safety issues have all hindered successful delivery and effective outcomes despite a variety of treatment options. In the current review, we covered the intranasal route, an alternative strategic route targeting brain for improved delivery across the BBB. The trans-nasal pathway is non-invasive, directing therapeutics directly towards brain, circumventing the barrier and reducing peripheral exposure. The delivery of nanosized vesicles loaded with drugs was also covered in the review. Nanovesicle systems are organised in concentric bilayered lipid membranes separated with aqueous layers. These carriers surmount the disadvantages posed by intranasal delivery of rapid mucociliary clearance and enzymatic degradation, and enhance retention of drug to reach the site of target. In conclusion, the review covers in-depth conclusions on numerous aspects of formulation of drug-loaded vesicular system delivery across BBB, current marketed nasal devices, significant jeopardies, potential therapeutic aids, and current advancements followed by future perspectives.

Polymeric nanoparticles for DNA vaccine-based cancer immunotherapy: a review

Cancer is one of the leading causes of death and mortality in the world. There is an essential need to develop new drugs or therapeutic approaches to manage treatment-resistant cancers. Cancer immunotherapy is a type of cancer treatment that uses the power of the body's immune system to prevent, control, and eliminate cancer. One of the materials used as a vaccine in immunotherapy is DNA. The application of polymeric nanoparticles as carriers for DNA vaccines could be an effective therapeutic approach to activate immune responses and increase antigen presentation efficiency. Various materials have been used as polymeric nanoparticles, including: chitosan, poly (lactic-co-glycolic acid), Polyethylenimine, dendrimers, polypeptides, and polyesters. Application of these polymer nanoparticles has several advantages, including increased vaccine delivery, enhanced antigen presentation, adjuvant effects, and more sustainable induction of the immune system. Besides many clinical trials and commercial products that were developed based on polymer nanoparticles, there is still a need for more comprehensive studies to increase the DNA vaccine efficiency in cancer immunotherapy using this type of carrier.

Lactoferrin: Antimicrobial impacts, genomic guardian, therapeutic uses and clinical significance for humans and animals

Lactoferrin (LF) is a protein found in several bodily fluids, such as milk. This protein has a diverse range of functions and is evolutionarily conserved. Lactoferrin is a multifunction protein with distinct biological abilities affecting mammals' immune structures. Reports indicated that the daily uptake of LF from dairy products is unsatisfactory in detecting further health-promoting abilities. Research has shown that it protects against infection, mitigates cellular senescence, and improves nutritional quality. Additionally, LF is being studied as a potential treatment for various diseases and conditions, including gastrointestinal issues and infections. Studies have also demonstrated its effectiveness against various viruses and bacteria. In this article, we'll look closer at the structure of LF and its various biological activities, including its antimicrobial, anti-viral, anti-cancer, anti-osteoporotic, detoxifying, and immunomodulatory properties. More specifically, the protective effect of LF against oxidative DNA damage was also clarified through its ability to abolish DNA damaging issues without interfacing with host genetic material. Fortification with LF protects mitochondria dysfunction syndromes via sustaining redox status and biogenesis and suppressing apoptosis and autophagy singling. Additionally, we'll examine the potential benefits of lactoferrin and provide an overview of recent clinical trials conducted to examine its use in laboratory and living models.

Nitrile-Containing Terpyridyl Zn(II)-Coordination Polymer-Based Metallogelators Displaying Helical Structures: Synthesis, Structures, and "Druglike" Action against B16-F10 Melanoma Cells

An attempt has been made to develop a self-drug-delivery system against melanoma from a series of metallogelators derived from coordination polymers. Thus, a series of coordination polymers (CP1-CP6) derived from a nitrile-containing terpyridyl ligand (L) and transition metal salts (Cu(I)/Zn(II)) have been synthesized and thoroughly characterized by a number of physicochemical techniques including single crystal X-ray diffraction. Reactions of the ingredients of the coordination polymers guided by their single crystal structures produced four metallogels (CPG2-CPG5) which were characterized by dynamic rheology and TEM. The metallogelator CPG3 turned out to be the best suited for further studies as revealed from MTT assay against melanoma (B16-F10) and macrophage (RAW 264.7) cells. Various experiments (scratch, cell cycle, nuclear condensation, annexin V-FITC/PI, mitochondrial membrane potential, Ho-efflux assays) not only supported the "druglike" action against melanoma B16-F10 cells but also suggested that the mechanism of cancer cell death was via mitochondrial membrane potential depolarization-driven apoptosis. Because melanoma B16-F10 is a model cell line for human skin cancer, the metallogel CPG3 may, therefore, be further developed for such treatment.

Platin-C containing nanoparticles: a recipe for the delivery of curcumin-cisplatin combination chemotherapeutics to mitochondria

The success story of cisplatin spans over six decades now and yet it continues to be the key player in most chemotherapeutic regimens. Numerous efforts have been made to improve its efficacy, address its shortcomings, and overcome drug resistance. One such strategy is to develop new platinum(IV)-based prodrugs with functionally active ligands to deliver combination therapeutics. This strategy not only enables the drug candidate to access multiple drug targets but also enhances the kinetic inertness of platinum complexes and thereby ensures greater accumulation of active drugs at the target site. We report the synthesis of Platin-C, a platinum(IV)-based cisplatin prodrug tethered to the active component of ancient herbal medicine, curcumin, as one of the axial ligands. This combination complex showed improved chemotherapeutic efficacy in cisplatin resistant A2780/CP70 cell lines compared with the individual components. An amine-terminated biodegradable polymer was suitably functionalized with the triphenylphosphonium (TPP) cation to obtain a mitochondria-directed drug delivery platform. Quantification of Platin-C loading into these NPs using complementary techniques employing curcumin optical properties in high-performance liquid chromatography and platinum-based inductively coupled plasma mass spectrometry evidenced efficacious payload incorporation resulting in functional activities of both the components. Stability studies for a period of one week indicated that the NPs remain stable, enabling substantial loading and controlled release of the prodrug. The targeting nanoparticle (NP) platform was utilized to deliver Platin-C primarily in the mitochondrial network of cancer cells as monitored using confocal microscopy employing the green fluorescence of the curcumin pendant. Our studies showed that amine terminated NPs were relatively less efficient in their ability to target mitochondria despite being positively charged. This re-validated the importance of lipophilic positively charged TPP surface functionalities to successfully target cellular mitochondria. We validated the capabilities of Platin-C and its mitochondria-targeting nanoparticles towards inflicting mitochondria-directed activity in cisplatin-sensitive and cisplatin-resistant cell lines. Furthermore, our studies also demonstrated the effectiveness of Platin-C incorporated targeting NPs in attenuating cellular inflammatory markers by utilizing the curcumin component. This study advances our understanding of the cisplatin prodrug approach to combine chemotherapeutic and inflammatory effects in accessing combinatory pathways.

Mitochondrial Dysfunction: The Hidden Player in the Pathogenesis of Atherosclerosis?

Atherosclerosis is a multifactorial inflammatory pathology that involves metabolic processes. Improvements in therapy have drastically reduced the prognosis of cardiovascular disease. Nevertheless, a significant residual risk is still relevant, and is related to unmet therapeutic targets. Endothelial dysfunction and lipid infiltration are the primary causes of atherosclerotic plaque progression. In this contest, mitochondrial dysfunction can affect arterial wall cells, in particular macrophages, smooth muscle cells, lymphocytes, and endothelial cells, causing an increase in reactive oxygen species (ROS), leading to oxidative stress, chronic inflammation, and intracellular lipid deposition. The detection and characterization of mitochondrial DNA (mtDNA) is crucial for assessing mitochondrial defects and should be considered the goal for new future therapeutic interventions. In this review, we will focus on a new idea, based on the analysis of data from many research groups, namely the link between mitochondrial impairment and endothelial dysfunction and, in particular, its effect on atherosclerosis and aging. Therefore, we discuss known and novel mitochondria-targeting therapies in the contest of atherosclerosis.

Structural and functional diversity of mitochondria in vestibular/cochlear hair cells and vestibular calyx afferents

Mitochondria supply energy in the form of ATP to drive a plethora of cellular processes. In heart and liver cells, mitochondria occupy over 20% of the cellular volume and the major need for ATP is easily identifiable - i.e., to drive cross-bridge recycling in cardiac cells or biosynthetic machinery in liver cells. In vestibular and cochlear hair cells the overall cellular mitochondrial volume is much less, and mitochondria structure varies dramatically in different regions of the cell. The regional demands for ATP and cellular forces that govern mitochondrial structure and localization are not well understood. Below we review our current understanding of the heterogeneity of form and function in hair cell mitochondria. A particular focus of this review will be on regional specialization in vestibular hair cells, where large mitochondria are found beneath the cuticular plate in close association with the striated organelle. Recent findings on the role of mitochondria in hair cell death and aging are covered along with potential therapeutic approaches. Potential avenues for future research are discussed, including the need for integrated computational modeling of mitochondrial function in hair cells and the vestibular afferent calyx.

Nanovaccines: Merits, and diverse roles in boosting antitumor immune responses

An attractive type of cancer immunotherapy is cancer therapeutic vaccines that induce antitumor immunity effectively. Although supportive results in the recent vaccine studies, there are still numerous drawbacks, such as poor stability, weak immunogenicity and strong toxicity, to be tackled for promoting the potency and durability of antitumor efficacy. NPs (Nanoparticles)-based vaccines offer unique opportunities to breakthrough the current bottleneck. As a rule, nanovaccines are new the generations of vaccines that use NPs as carriers and/or adjuvants. Several advantages of nanovaccines are constantly explored, including optimal nanometer size, high stability, plenty of antigen loading, enhanced immunogenicity, tunable antigen presentation, more retention in lymph nodes and promote patient compliance by a lower frequency of dosing. Here, we summarized the merits and highlight the diverse role nanovaccines play in improving antitumor responses.

Recent Advances in DNA Vaccines against Lung Cancer: A Mini Review

Lung cancer is regarded as the major causes of patient death around the world. Although the novel tumor immunotherapy has made great progress in the past decades, such as utilizing immune checkpoint inhibitors or oncolytic viruses, the overall 5-year survival of patients with lung cancers is still low. Thus, development of effective vaccines to treat lung cancer is urgently required. In this regard, DNA vaccines are now considered as a promising immunotherapy strategy to activate the host immune system against lung cancer. DNA vaccines are able to induce both effective humoral and cellular immune responses, and they possess several potential advantages such as greater stability, higher safety, and being easier to manufacture compared to conventional vaccination. In the present review, we provide a global overview of the mechanism of cancer DNA vaccines and summarize the innovative neoantigens, delivery platforms, and adjuvants in lung cancer that have been investigated or approved. Importantly, we highlight the recent advance of clinical studies in the field of lung cancer DNA vaccine, focusing on their safety and efficacy, which might accelerate the personalized design of DNA vaccine against lung cancer.

In vivo fate and intracellular trafficking of vaccine delivery systems

With the pandemic of severe acute respiratory syndrome coronavirus 2, vaccine delivery systems emerged as a core technology for global public health. Given that antigen processing takes place inside the cell, the intracellular delivery and trafficking of a vaccine antigen will contribute to vaccine efficiency. Investigations focusing on the in vivo behavior and intracellular transport of vaccines have improved our understanding of the mechanisms relevant to vaccine delivery systems and facilitated the design of novel potent vaccine platforms. In this review, we cover the intracellular trafficking and in vivo fate of vaccines administered via various routes and delivery systems. To improve immune responses, researchers have used various strategies to modulate vaccine platforms and intracellular trafficking. In addition to progress in vaccine trafficking studies, the challenges and future perspectives for designing next-generation vaccines are discussed.

Chlorine disinfection elevates the toxicity of polystyrene microplastics to human cells by inducing mitochondria-dependent apoptosis

Microplastics (MPs) are ubiquitous in drinking water and pose potential threats to human health. Despite increasingly attentions on the toxicity of MPs, the deleterious effects of MPs after chlorine disinfection, which might be a more accessible form of MPs, has rarely been considered. Here, we first treated pristine polystyrene microplastics (PS-MPs) with chlorine to simulate the reactions that occur during drinking water treatment, and investigated and compared the cytotoxicity of chlorinated PS-MPs to those of pristine PS-MPs. Chlorine disinfection did not change the size of pristine PS-MPs, but increased the surface roughness. In addition, abundant carbon-chlorine bonds and persistent free radicals were generated on the surface of chlorinated PS-MPs. Compared with pristine PS-MPs, chlorinated PS-MPs markedly inhibited the cell proliferation, changed cellular morphology, destroyed cell membrane integrity, induced cell inflammatory response and apoptosis. Proteomics confirmed the difference in interactions with intracellular proteins between these particles. Furthermore, we found that the regulation of PI3K/AKT and Bcl-2/Bax pathways, oxidative stress-triggered mitochondrial depolarization, and the activation of caspase cascade were identified as the underlying mechanisms for the enhanced apoptosis ratio in GES-1 cells when exposed to chlorinated PS-MPs. This exacerbated cytotoxicity could be explained by the enhanced surface roughness and changed surface chemistry of these PS-MPs after chlorine disinfection. This work discloses the impacts of chlorine disinfection on the cytotoxicity of PS-MPs, which provides new insights for a more systematic risk assessment of MPs.

The effect of lactoferrin in aging: role and potential

Aging is frequently accompanied by various types of physiological deterioration, which increases the risk of human pathologies. Global public health efforts to increase human lifespan have increasingly focused on lowering the risk of aging-related diseases, such as diabetes, neurodegenerative diseases, cardiovascular disease, and cancers. Dietary intervention is a promising approach to maintaining human health during aging. Lactoferrin (LF) is known for its physiologically pleiotropic properties. Anti-aging interventions of LF have proven to be safe and effective for various pharmacological activities, such as anti-oxidation, anti-cellular senescence, anti-inflammation, and anti-carcinogenic. Moreover, LF has a pivotal role in modulating the major signaling pathways that influence the longevity of organisms. Thus, LF is expected to be able to attenuate the process of aging and greatly ameliorate its effects.

Multifunctional Mitochondria-Targeting Nanosystems for Enhanced Anticancer Efficacy

Mitochondria, a kind of subcellular organelle, play crucial roles in cancer cells as an energy source and as a generator of reactive substrates, which concern the generation, proliferation, drug resistance, and other functions of cancer. Therefore, precise delivery of anticancer agents to mitochondria can be a novel strategy for enhanced cancer treatment. Mitochondria have a four-layer structure with a high negative potential, which thereby prevents many molecules from reaching the mitochondria. Luckily, the advances in nanosystems have provided enormous hope to overcome this challenge. These nanosystems include liposomes, nanoparticles, and nanomicelles. Here, we summarize the very latest developments in mitochondria-targeting nanomedicines in cancer treatment as well as focus on designing multifunctional mitochondria-targeting nanosystems based on the latest nanotechnology.

Potential of Sorghum Polyphenols to Prevent and Treat Alzheimer's Disease: A Review Article

Alzheimer's disease (AD) is characterized by the excessive deposition of extracellular amyloid-beta peptide (Aβ) and the build-up of intracellular neurofibrillary tangles containing hyperphosphorylated tau proteins. This leads to neuronal damage, cell death and consequently results in memory and learning impairments leading to dementia. Although the exact cause of AD is not yet clear, numerous studies indicate that oxidative stress, inflammation, and mitochondrial dysfunction significantly contribute to its onset and progression. There is no effective therapeutic approach to stop the progression of AD and its associated symptoms. Thus, early intervention, preferably, pre-clinically when the brain is not significantly affected, is a better option for effective treatment. Natural polyphenols (PP) target multiple AD-related pathways such as protecting the brain from Aβ and tau neurotoxicity, ameliorating oxidative damage and mitochondrial dysfunction. Among natural products, the cereal crop sorghum has some unique features. It is one of the major global grain crops but in the developed world, it is primarily used as feed for farm animals. A broad range of PP, including phenolic acids, flavonoids, and condensed tannins are present in sorghum grain including some classes such as proanthocyanidins that are rarely found in others plants. Pigmented varieties of sorghum have the highest polyphenolic content and antioxidant activity which potentially makes their consumption beneficial for human health through different pathways such as oxidative stress reduction and thus the prevention and treatment of neurodegenerative diseases. This review summarizes the potential of sorghum PP to beneficially affect the neuropathology of AD.

Engineering Mitochondriotropic Carbon Dots for Targeting Cancer Cells

Aiming to understand and enhance the capacity of carbon dots (CDs) to transport through cell membranes and target subcellular organelles—in particular, mitochondria—a series of nitrogen-doped CDs were prepared by the one-step microwave-assisted pyrolysis of citric acid and ethylenediamine. Following optimization of the reaction conditions for maximum fluorescence, functionalization at various degrees with alkylated triphenylphosphonium functional groups of two different alkyl chain lengths afforded a series of functionalized CDs that exhibited either lysosome or mitochondria subcellular localization. Further functionalization with rhodamine B enabled enhanced fluorescence imaging capabilities in the visible spectrum and allowed the use of low quantities of CDs in relevant experiments. It was thus possible, by the appropriate selection of the alkyl chain length and degree of functionalization, to attain successful mitochondrial targeting, while preserving non-toxicity and biocompatibility. In vitro cell experiments performed on normal as well as cancer cell lines proved their non-cytotoxic character and imaging potential, even at very low concentrations, by fluorescence microscopy. Precise targeting of mitochondria is feasible with carefully designed CDs that, furthermore, are specifically internalized in cells and cell mitochondria of high transmembrane potential and thus exhibit selective uptake in malignant cells compared to normal cells.

Development of Effective Tumor Vaccine Strategies Based on Immune Response Cascade Reactions

To solve the problems of high toxicity and poor efficacy of existing tumor treatment methods, researchers have developed a variety of tumor immunotherapies. Among them, tumor vaccines activate antigen-presenting cells and T lymphocytes upstream of the cancer-immunity cycle are considered the most promising therapy to activate the immune system. Nanocarriers are considered the most promising tumor vaccine delivery vehicles, including polymer nanocarriers, lipid nanocarriers, inorganic nanocarriers, and biomimetic nanocarriers that have been developed for vaccine delivery. Based on the cascade reaction for tumor vaccines to exert their effects, this review summarizes the four key factors for the design and construction of nano-tumor vaccines. The composition and functional characteristics of the corresponding preferred nanocarriers are illustrated to provide a reference for the development of effective tumor vaccines. Finally, potential challenges and perspectives are illustrated in the hope of improving the efficacy of tumor vaccine immunotherapy and accelerating the clinical transformation of next-generation tumor vaccines.

Calycosin-loaded nanoliposomes as potential nanoplatforms for treatment of diabetic nephropathy through regulation of mitochondrial respiratory function

BACKGROUNDS

One of the most common complications in diabetic nephropathy is generation of high levels of ROS which can be regulated by herbal antioxidants. However, polyphenols like calycosin, the bioactive compound of Radix astragali suffer from low solubility and poor bioavailability.

METHODS

Therefore, in the present study, calycosin-loaded nanoliposomes were fabricated and characterized by TEM, DLS and FTIR techniques. Afterwards, the drug loading (DL) and entrapment efficiency (EE), drug release, solubility, stability, and pharmacodynamic assays were performed. Finally, the antinephropathic effects of calycosin-loaded-nanoliposomes on mitochondria of kidney cells were explored by MTT, ROS, MDA, mitochondrial respiratory function assays.

RESULTS

The result showed that the size, hydrodynamic radius, zeta potential, EE, and DL were, 80 nm, 133.99 ± 21.44 nm, - 20.53 ± 3.57, 88.37 ± 2.28%, and 7.48 ± 1.19%, respectively. The outcomes of in vitro release assay showed that calycosin-loaded nanoliposomes were significantly slow-release in dialysis media with pH 1.2, pH 6.9 and pH 7.4, at about 30 min, the dissolution of calycosin from nanoliposome became almost complete, and after 2 months, the calycosin-loaded nanoliposomes were still stable. Pharmacokinetic assay revealed that the AUC0-t of calycosin in calycosin-loaded nanoliposome group was 927.39 ± 124.91 μg/L*h, which was 2.26 times than that of the free calycosin group (**P < 0.01). Additionally, the MRT0-t and t1/2 of calycosin in the calycosin-loaded nanoliposome group were prolonged by 1.54 times and 1.33 times than that of free calycosin group, respectively (*P < 0.05). Finally, it was shown that calycosin-loaded nanoliposomes regulated the viability, ROS production, lipid peroxidation and function of mitochondria in kidney cells of diabetic rats as a model of diabetic nephropathy.

CONCLUSION

In conclusion it may be suggested that new therapies based on nano-formulated calycosin can restore mitochondrial function which can improve diabetic nephropathy.

Pharmacological intervention in oxidative stress as a therapeutic target in neurological disorders

OBJECTIVES

Oxidative stress is a major cellular burden that triggers reactive oxygen species (ROS) and antioxidants that modulate signalling mechanisms. Byproducts generated from this process govern the brain pathology and functions in various neurological diseases. As oxidative stress remains the key therapeutic target in neurological disease, it is necessary to explore the multiple routes that can significantly repair the damage caused due to ROS and consequently, neurodegenerative disorders (NDDs). Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase is the critical player of oxidative stress that can also be used as a therapeutic target to combat NDDs.

KEY FINDINGS

Several antioxidants signalling pathways are found to be associated with oxidative stress and show a protective effect against stressors by increasing the release of various cytoprotective enzymes and also exert anti-inflammatory response against this oxidative damage. These pathways along with antioxidants and reactive species can be the defined targets to eliminate or reduce the harmful effects of neurological diseases.

SUMMARY

Herein, we discussed the underlying mechanism and crucial role of antioxidants in therapeutics together with natural compounds as a pharmacological tool to combat the cellular deformities cascades caused due to oxidative stress.

The reversal of chemotherapy-induced multidrug resistance by nanomedicine for cancer therapy

Multidrug resistance (MDR) of cancer is a persistent problem in chemotherapy. Scientists have considered the overexpressed efflux transporters responsible for MDR and chemotherapy failure. MDR extremely limits the therapeutic effect of chemotherapy in cancer treatment. Many strategies have been applied to solve this problem. Multifunctional nanoparticles may be one of the most promising approaches to reverse MDR of tumor. These nanoparticles can keep stability in the blood circulation and selectively accumulated in the tumor microenvironment (TME) either by passive or active targeting. The stimuli-sensitive or organelle-targeting nanoparticles can release the drug at the targeted-site without exposure to normal tissues. In order to better understand reversal of MDR, three main strategies are concluded in this review. First strategy is the synergistic effect of chemotherapeutic drugs and ABC transporter inhibitors. Through directly inhibiting overexpressed ABC transporters, chemotherapeutic drugs can enter into resistant cells without being efflux. Second strategy is based on nanoparticles circumventing over-expressed efflux transporters and directly targeting resistance-related organelles. Third approach is the combination of multiple therapy modes overcoming cancer resistance. At last, numerous researches demonstrated cancer stem-like cells (CSCs) had a deep relation with drug resistance. Here, we discuss two different drug delivery approaches of nanomedicine based on CSC therapy.

Atherosclerosis as Mitochondriopathy: Repositioning the Disease to Help Finding New Therapies

Atherosclerosis is a complex pathology that involves both metabolic dysfunction and chronic inflammatory process. During the last decade, a considerable progress was achieved in describing the pathophysiological features of atherosclerosis and developing approaches that target the abnormal lipid metabolism and chronic inflammation. However, early events in the arterial wall that initiate the disease development still remain obscure. Finding effective therapeutic targets in these early processes would allow developing methods for disease prevention and, possibly, atherosclerotic plaque regression. Currently, these early events are being actively studied by several research groups. One of the processes that are being investigated is the development of mitochondrial dysfunction, which was demonstrated to be present in the affected areas of the arterial wall. Detection and characterization of mitochondrial dysfunction associated with several chronic human disorders was made possible by the improved methods of studying mitochondrial biology and detecting mitochondrial DNA (mtDNA) mutations. It was found to be involved in several key atherogenic processes, such as oxidative stress, chronic inflammation, and intracellular lipid accumulation. Mitochondrial dysfunction can occur in all types of cells involved in the pathogenesis of atherosclerosis: monocytes and macrophages, smooth muscle cells, lymphocytes, and the endothelial cells. However, therapies that would specifically target the mitochondria to correct mitochondrial dysfunction and neutralize the defective organelles are still remain to be developed and characterized. The aim of this review is to outline the prospects for mitochondrial therapy for atherosclerosis. We discuss mechanisms of mitochondria-mediated atherogenic processes, known mitochondria-targeting therapy strategies, and novel mitochondria-targeting drugs in the context of atherosclerosis.

Mitochondrion-specific dendritic lipopeptide liposomes for targeted sub-cellular delivery

The mitochondrion is an important sub-cellular organelle responsible for the cellular energetic source and processes. Owing to its unique sensitivity to heat and reactive oxygen species, the mitochondrion is an appropriate target for photothermal and photodynamic treatment for cancer. However, targeted delivery of therapeutics to mitochondria remains a great challenge due to their location in the sub-cellular compartment and complexity of the intracellular environment. Herein, we report a class of the mitochondrion-targeted liposomal delivery platform consisting of a guanidinium-based dendritic peptide moiety mimicking mitochondrion protein transmembrane signaling to exert mitochondrion-targeted delivery with pH sensitive and charge-reversible functions to enhance tumor accumulation and cell penetration. Compared to the current triphenylphosphonium (TPP)-based mitochondrion targeting system, this dendritic lipopeptide (DLP) liposomal delivery platform exhibits about 3.7-fold higher mitochondrion-targeted delivery efficacy. Complete tumor eradication is demonstrated in mice bearing 4T1 mammary tumors after combined photothermal and photodynamic therapies delivered by the reported DLP platform.

Recent progress in mitochondria-targeting-based nanotechnology for cancer treatment

Mitochondria play critical roles in the regulation of the proliferation and apoptosis of cancerous cells. Nanosystems for targeted delivery of cargos to mitochondria for cancer treatment have attracted increasing attention in the past few years. This review will summarize the state of the art of design and construction of nanosystems used for mitochondria-targeted delivery. The use of nanotechnology for cancer treatment through various pathways such as energy metabolism interference, reactive oxygen species (ROS) regulation, mitochondrial protein targeting, mitochondrial DNA (mtDNA) interference, mitophagy inducing, and combination therapy will be discussed. Finally, the major challenges and an outlook in this field will also be provided.

Cancer Vaccines, Adjuvants, and Delivery Systems

Vaccination was first pioneered in the 18th century by Edward Jenner and eventually led to the development of the smallpox vaccine and subsequently the eradication of smallpox. The impact of vaccination to prevent infectious diseases has been outstanding with many infections being prevented and a significant decrease in mortality worldwide. Cancer vaccines aim to clear active disease instead of aiming to prevent disease, the only exception being the recently approved vaccine that prevents cancers caused by the Human Papillomavirus. The development of therapeutic cancer vaccines has been disappointing with many early cancer vaccines that showed promise in preclinical models often failing to translate into efficacy in the clinic. In this review we provide an overview of the current vaccine platforms, adjuvants and delivery systems that are currently being investigated or have been approved. With the advent of immune checkpoint inhibitors, we also review the potential of these to be used with cancer vaccines to improve efficacy and help to overcome the immune suppressive tumor microenvironment.

Medicinal applications and molecular targets of dequalinium chloride

For more than 60 years dequalinium chloride (DQ) has been used as anti-infective drug, mainly to treat local infections. It is a standard drug to treat bacterial vaginosis and an active ingredient of sore-throat lozenges. As a lipophilic bis-quaternary ammonium molecule, the drug displays membrane effects and selectively targets mitochondria to deplete DNA and to block energy production in cells. But beyond its mitochondriotropic property, DQ can interfere with the correct functioning of diverse proteins. A dozen of DQ protein targets have been identified and their implication in the antibacterial, antiviral, antifungal, antiparasitic and anticancer properties of the drug is discussed here. The anticancer effects of DQ combine a mitochondrial action, a selective inhibition of kinases (PKC-α/β, Cdc7/Dbf4), and a modulation of Ca²⁺-activated K⁺ channels. At the bacterial level, DQ interacts with different multidrug transporters (QacR, AcrB, EmrE) and with the transcriptional regulator RamR. Other proteins implicated in the antiviral (MPER domain of gp41 HIV-1) and antiparasitic (chitinase A from Vibrio harveyi) activities have been identified. DQ also targets α -synuclein oligomers to restrict protofibrils formation implicated in some neurodegenerative disorders. In addition, DQ is a typical bolaamphiphile molecule, well suited to form liposomes and nanoparticules useful for drug entrapment and delivery (DQAsomes and others). Altogether, the review highlights the many pharmacological properties and therapeutic benefits of this old 'multi-talented' drug, which may be exploited further. Its multiple sites of actions in cells should be kept in mind when using DQ in experimental research.

Tailoring functional nanostructured lipid carriers for glioblastoma treatment with enhanced permeability through in-vitro 3D BBB/BBTB models

The blood-brain barrier (BBB) and blood-brain tumour barrier (BBTB) pose a significant challenge to drug delivery to brain tumours, including aggressive glioblastoma (GB). The present study rationally designed functional nanostructured lipid carriers (NLC) to tailor their BBB penetrating properties with high encapsulation of CNS negative chemotherapeutic drug docetaxel (DTX). We investigated the effect of four liquid lipids, propylene glycol monolaurate (Lauroglycol® 90), Capryol® propylene glycol monocaprylate, caprylocaproylmacrogol-8-glycerides (Labrasol®) and polyoxyl-15-hydroxystearate (Kolliphor® HS15) individually and in combination to develop NLCs with effective permeation across in-vitro 3D BBB model without alteration in the integrity of the barrier. With desirable spherical shape as revealed by TEM and an average particle size of 123.3 ± 0.642 nm and zeta potential of -32 mV, DTX-NLCs demonstrated excellent stability for six months in its freeze-dried form. The confocal microscopy along with flow cytometry data revealed higher internalisation of DTX-NLCs in U87MG over SVG P12 cells. Micropinocytosis was observed to be one of the dominant pathways for internalisation in U87MG cells while clathrin-mediated pathway was more predominat in patient-derived glioblastoma cells. The NLCs readily penetrated the actively proliferating peripheral cells on the surface of the 3D tumour spheroids as compared to the necrotic core. The DTX-NLCs induced cell arrest through G2/M phase with a significant decrease in the mitochondrial reserve capacity of cells. The NLCs circumvented BBTB with high permeability followed by accumulation in glioblastoma cells with patient-derived cells displaying ~2.4-fold higher uptake in comparison to U87MG when studied in a 3D in-vitro model of BBTB/GB. We envisage this simple and industrially feasible technology as a potential candidate to be developed as GB nanomedicine.

Nanomedicines for Subcellular Targeting: The Mitochondrial Perspective

BACKGROUND

Over the past decade, there has been a surge in the number of mitochondrialactive therapeutics for conditions ranging from cancer to aging. Subcellular targeting interventions can modulate adverse intracellular processes unique to the compartments within the cell. However, there is a dearth of reviews focusing on mitochondrial nano-delivery, and this review seeks to fill this gap with regards to nanotherapeutics of the mitochondria.

METHODS

Besides its potential for a higher therapeutic index than targeting at the tissue and cell levels, subcellular targeting takes into account the limitations of systemic drug administration and significantly improves pharmacokinetics. Hence, an extensive literature review was undertaken and salient information was compiled in this review.

RESULTS

From literature, it was evident that nanoparticles with their tunable physicochemical properties have shown potential for efficient therapeutic delivery, with several nanomedicines already approved by the FDA and others in clinical trials. However, strategies for the development of nanomedicines for subcellular targeting are still emerging, with an increased understanding of dysfunctional molecular processes advancing the development of treatment modules. For optimal delivery, the design of an ideal carrier for subcellular delivery must consider the features of the diseased microenvironment. The functional and structural features of the mitochondria in the diseased state are highlighted and potential nano-delivery interventions for treatment and diagnosis are discussed.

CONCLUSION

This review provides an insight into recent advances in subcellular targeting, with a focus on en route barriers to subcellular targeting. The impact of mitochondrial dysfunction in the aetiology of certain diseases is highlighted, and potential therapeutic sites are identified.

Mitochondrial responses to organelle-specific drug delivering nanoparticles composed of polypeptide and peptide complexes

Aims: The mechanistic study of the drug carrier-target interactions of mitochondria-unique nanoparticles composed of polypeptide-peptide complexes (mPoP-NPs). Materials & methods: The isolated organelles were employed to address the direct effects of mPoP-NPs on dynamic structure and functional wellbeing of mitochondria. Mitochondria morphology, respiration, membrane potential, reactive oxygen species generation, were examined by confocal microscopy, flow cytometry and oxygraphy. Lonidamine-encapsulated formulation was assessed to evaluate the drug delivery capacity of the naive nanoparticles. Results: The mPoP-NPs do not alter mitochondria structure and performance upon docking to organelles, while successfully delivering drug that causes organelle dysfunction. Conclusion: The study gives insight into interactions of mPoP-NPs with mitochondria and provides substantial support for consideration of designed nanoparticles as biocompatible and efficient mitochondria-targeted platforms.

Mitochondria-Targeting Oxygen-Sufficient Perfluorocarbon Nanoparticles for Imaging-Guided Tumor Phototherapy

Background

Although photothermal therapy (PTT) and photodynamics therapy (PDT) have both made excellent progress in tumor therapy, the effectiveness of using PTT or PDT alone is dissatisfactory due to the limitations of the penetration depth in PTT and the hypoxic microenvironment of tumors for PDT. Combination phototherapy has currently become a burgeoning cancer treatment.

Methods and Materials

In this work, a mitochondria-targeting liquid perfluorocarbon (PFC)-based oxygen delivery system was developed for the synergistic PDT/photothermal therapy (PTT) of cancer through image guiding.

Results

Importantly, these nanoparticles (NPs) can effectively and accurately accumulate in the target tumor via the enhanced permeability and retention (EPR) effect.

Conclusion

This approach offers a novel technique to achieve outstanding antitumor efficacy by an unprecedented design with tumor mitochondria targeting, oxygen delivery, and synergistic PDT/PTT with dual-imaging guidance.

Designing Metallogelators Derived from NSAID-based Zn(II) Coordination Complexes for Drug-Delivery Applications

A crystal engineering approach has been invoked to design a new series of eight Zn(II) coordination complexes derived from various non-steroidal anti-inflammatory drugs (NSAIDs), namely diclofenac (DIC), ibuprofen (IBU), naproxen (NAP), flufenamic acid (FLU) and meclofenamic acid (MEC), and two co-ligands, namely N-phenyl-3-pyridylamide (3-Py) and N-phenyl-4-pyridylamide (4-Py), and Zn(NO₃ )₂ as potential supramolecular gelators. Half of the coordination complexes thus synthesized were able to form aqueous gels (MG-3-PyMEC, MG-3-PyDIC, MG-4-PyNAP and MG-4-PyMEC). Single-crystal structures of all eight complexes revealed that they possessed a gelation-inducing 1D hydrogen-bonded network including amide…amide synthon in some cases, which supported strongly the design principles based on which these complexes were synthesized. Interestingly, one such metallogelator complex, namely 3-PyMEC, showed an intriguing anticancer property against a human breast cancer cell line (MDA-MB-231), as revealed by both MTT and cell migration assays.

Tumor Microenvironment Cascade-Responsive Nanodrug with Self-Targeting Activation and ROS Regeneration for Synergistic Oxidation-Chemotherapy

Carrier-free nanodrug with exceptionally high drug payload has attracted increasing attentions. Herein, we construct a pH/ROS cascade-responsive nanodrug which could achieve tumor acidity-triggered targeting activation followed by circularly amplified ROS-triggered drug release via positive-feedback loop. The di-selenide-bridged prodrug synthesized from vitamin E succinate and methotrexate (MTX) self-assembles into nanoparticles (VSeM); decorating acidity-cleavable PEG onto VSeM surface temporarily shields the targeting ability of MTX to evade immune clearance and consequently elongate circulation time. Upon reaching tumor sites, acidity-triggered detachment of PEG results in targeting recovery to enhance tumor cell uptake. Afterward, the VSeM could be dissociated in response to intracellular ROS to trigger VES/MTX release; then the released VES could produce extra ROS to accelerate the collapse of VSeM. Finally, the excessive ROS produced from VES could synergize with the released MTX to efficiently suppress tumor growth via orchestrated oxidation-chemotherapy. Our study provides a novel strategy to engineer cascade-responsive nanodrug for synergistic cancer treatment.

Mitochondrion-Directed Nanoparticles Loaded with a Natural Compound and a microRNA for Promoting Cancer Cell Death via the Modulation of Tumor Metabolism and Mitochondrial Dynamics

Mitochondrial dysfunction may cause cancer and metabolic syndrome. Ellagic acid (abbreviated as E), a phytochemical, possesses anticancer activity. MicroRNA 125 (miR-125) may regulate metabolism. However, E has low aqueous solubility, and miR-125 is unstable in a biological fluid. Hence, this study aimed to develop nanoparticle formulations for the co-treatment of miR-125 and E. These nanoparticles were modified with one mitochondrion-directed peptide and a tumor-targeted ligand, and their modulating effects on mitochondrial dysfunction, antitumor efficacy, and safety in head and neck cancer (HNC) were evaluated. Results revealed that miR-125- and E-loaded nanoparticles effectively targeted cancer cells and intracellular mitochondria. The co-treatment significantly altered cellular bioenergetics, lipid, and glucose metabolism in human tongue squamous carcinoma SAS cells. This combination therapy also regulated protein expression associated with bioenergenesis and mitochondrial dynamics. These formulations also modulated multiple pathways of tumor metabolism, apoptosis, resistance, and metastasis in SAS cells. In vivo mouse experiments showed that the combined treatment of miR-125 and E nanoparticles exhibited significant hypoglycemic and hypolipidemic effects. The combinatorial therapy of E and miR-125 nanoparticles effectively reduced SAS tumor growth. To our best knowledge, this prospective study provided a basis for combining miRNA with a natural compound in nanoformulations to regulate mitochondrial dysfunction and energy metabolism associated with cancer.

Prevention of 7-Ketocholesterol-Induced Overproduction of Reactive Oxygen Species, Mitochondrial Dysfunction and Cell Death with Major Nutrients (Polyphenols, ω3 and ω9 Unsaturated Fatty Acids) of the Mediterranean Diet on N2a Neuronal Cells

The brain, which is a cholesterol-rich organ, can be subject to oxidative stress in a variety of pathophysiological conditions, age-related diseases and some rare pathologies. This can lead to the formation of 7-ketocholesterol (7KC), a toxic derivative of cholesterol mainly produced by auto-oxidation. So, preventing the neuronal toxicity of 7KC is an important issue to avoid brain damage. As there are numerous data in favor of the prevention of neurodegeneration by the Mediterranean diet, this study aimed to evaluate the potential of a series of polyphenols (resveratrol, RSV; quercetin, QCT; and apigenin, API) as well as ω3 and ω9 unsaturated fatty acids (α-linolenic acid, ALA; eicosapentaenoic acid, EPA; docosahexaenoic acid, DHA, and oleic acid, OA) widely present in this diet, to prevent 7KC (50 µM)-induced dysfunction of N2a neuronal cells. When polyphenols and fatty acids were used at non-toxic concentrations (polyphenols: ≤6.25 µM; fatty acids: ≤25 µM) as defined by the fluorescein diacetate assay, they greatly reduce 7KC-induced toxicity. The cytoprotective effects observed with polyphenols and fatty acids were comparable to those of α-tocopherol (400 µM) used as a reference. These polyphenols and fatty acids attenuate the overproduction of reactive oxygen species and the 7KC-induced drop in mitochondrial transmembrane potential (ΔΨm) measured by flow cytometry after dihydroethidium and DiOC₆(3) staining, respectively. Moreover, the studied polyphenols and fatty acids reduced plasma membrane permeability considered as a criterion for cell death measured by flow cytometry after propidium iodide staining. Our data show that polyphenols (RSV, QCT and API) as well as ω3 and ω9 unsaturated fatty acids (ALA, EPA, DHA and OA) are potent cytoprotective agents against 7KC-induced neurotoxicity in N2a cells. Their cytoprotective effects could partly explain the benefits of the Mediterranean diet on human health, particularly in the prevention of neurodegenerative diseases.

Advances in nanotechnology-based strategies for the treatments of amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS), also known as motor neuron disease (MND), is a progressive neurodegenerative disease that affects both upper and lower motor neurons, which results in loss of muscle control and eventual paralysis [1]. Currently, there are as yet unresolved challenges regarding efficient drug delivery into the central nervous system (CNS). These challenges can be attributed to multiple factors including the presence of the blood-brain barrier (BBB), blood-spinal cord barrier (BSCB), as well as the inherent characteristics of the drugs themselves (e.g. low solubility, insufficient bioavailability/bio-stability, 'off-target' effects) etc. As a result, conventional drug delivery systems may not facilitate adequate dosage of the required drugs for functional recovery in ALS patients. Nanotechnology-based strategies, however, employ engineered nanostructures that show great potential in delivering single or combined therapeutic agents to overcome the biological barriers, enhance interaction with targeted sites, improve drug bioavailability/bio-stability and achieve real-time tracking while minimizing the systemic side-effects. This review provides a concise discussion of recent advances in nanotechnology-based strategies in relation to combating specific pathophysiology relevant to ALS disease progression and investigates the future scope of using nanotechnology to develop innovative treatments for ALS patients.

Development of a nanoparticle that releases nucleic acids in response to a mitochondrial environment

The delivery of nucleic acids targeting mutant mtDNA represent a potential strategy for addressing a variety of mitochondria-related diseases. We previously developed a MITO-Porter, a nano carrier that is capable of delivering nanoparticles of nucleic acids to mitochondria of human cells. Here, we report on an investigation of a series of nanoparticles formed with various poly cationic peptides that can release nucleic acids in response to a mitochondrial environment. A significant relationship was found between the number of and the location of arginine and histidine residues in the peptide sequence and the release of nucleic acids in a mitochondrial environment.

A nanocarrier for the mitochondrial delivery of nucleic acids to cardiomyocytes

Cardiomyopathy caused by mitochondrial dysfunction associated with the mutation/deletion of mitochondrial DNA has been reported, and nucleic acid therapy targeting cardiac mitochondria represents a possible therapy for treating these diseases. Such a treatment, however, has not yet been achieved because delivering nucleic acids to mitochondria of cardiac muscle is difficult. In this study, H9c2 cells a type of rat cardiac myoblasts, were used as model cardiac muscle cells. The use of a lipid composition used to prepare the β-MEND (where MEND denotes multifunctional envelope-type nano device) permitted the particles to be efficiently internalized by H9c2 cells, as evidenced by flow cytometry analyses. Intracellular observations by confocal laser scanning microscopy showed that the β-MEND efficiently accumulated in mitochondria of H9c2 cells. We also constructed an RP/β-MEND that contained a mitochondrial RNA aptamer to achieve mitochondrial delivery in H9c2 cells. The successful direct mitochondrial transfection of exogenous RNA was confirmed using these carrier systems, based on PCR experiments after reverse transcription. Thus, the β-MEND holds promise as a direct mitochondrial transfection system for delivering nucleic acids targeted to H9c2 cells.

A neutral water-soluble mitochondria-targeting polymer

We report the first neutral and water-soluble polymer capable of strong mitochondrial targeting in vitro and in vivo, zwitterionic poly[2-(N-oxide-N,N-diethylamino)ethyl methacrylate] (OPDEA). OPDEA is quickly internalized via macropinocytosis by various cancer cells and transferred into the mitochondria, which slightly lowers the mitochondrial membrane potential as determined by the JC-1 assay.

Antitumor Effect of Lonidamine-Polypeptide-Peptide Nanoparticles in Breast Cancer Models

Biomaterials folded into nanoparticles (NPs) can be utilized as targeted drug delivery systems for cancer therapy. NPs may provide a vehicle for the anticancer drug lonidamine (LND), which inhibits glycolysis but was suspended from use at the clinical trial stage because of its hepatotoxicity due to poor solubility and pharmacokinetic properties. The NPs prepared by coassembly of the anionic polypeptide poly gamma glutamic acid (γ-PGA) and a designed amphiphilic and positively charged peptide (designated as mPoP-NPs) delivered LND to the mitochondria in cell cultures. In this study, we demonstrate that LND-mPoP-NP effective drug concentrations can be increased to reach therapeutically relevant concentrations. The self-assembled NP solution was subjected to snap-freezing and lyophilization and the resultant powder was redissolved in a tenth of the original volume. The NP size and their ability to target the proximity of the mitochondria of breast cancer cells were both maintained in this new formulation, C-LND-mPoP-NPs. Furthermore, these NPs exhibited 40% better cytotoxicity, relative to the nonlyophilized LND-mPoP-NPs and led to tumor growth inhibition with no adverse side effects upon intravenous administration in a xenograft breast cancer murine model.