An efficient method to isolate lemon derived extracellular vesicles for gastric cancer therapy

Plant-Derived Extracellular Vesicles and Their Exciting Potential as the Future of Next-Generation Drug Delivery

Plant cells release tiny membranous vesicles called extracellular vesicles (EVs), which are rich in lipids, proteins, nucleic acids, and pharmacologically active compounds. These plant-derived EVs (PDEVs) are safe and easily extractable and have been shown to have therapeutic effects against inflammation, cancer, bacteria, and aging. They have shown promise in preventing or treating colitis, cancer, alcoholic liver disease, and even COVID-19. PDEVs can also be used as natural carriers for small-molecule drugs and nucleic acids through various administration routes such as oral, transdermal, or injection. The unique advantages of PDEVs make them highly competitive in clinical applications and preventive healthcare products in the future. This review covers the latest methods for isolating and characterizing PDEVs, their applications in disease prevention and treatment, and their potential as a new drug carrier, with special attention to their commercial viability and toxicological profile, as the future of nanomedicine therapeutics. This review champions the formation of a new task force specializing in PDEVs to address a global need for rigor and standardization in PDEV research.

Plant-derived nanoparticles and plant virus nanoparticles: Bioactivity, health management, and delivery potential

Natural plants have acquired an increasing attention in biomedical research. Recent studies have revealed that plant-derived nanoparticles (PDNPs), which are nano-sized membrane vesicles released by plants, are one of the important material bases for the health promotion of natural plants. A great deal of research in this field has focused on nanoparticles derived from fresh vegetables and fruits. Generally, PDNPs contain lipids, proteins, nucleic acids, and other active small molecules and exhibit unique biological regulatory activity and editability. Specifically, they have emerged as important mediators of intercellular communication, and thus, are potentially suitable for therapeutic purposes. In this review, PDNPs were extensively explored; by evaluating them systematically starting from the origin and isolation, toward their characteristics, including morphological compositions, biological functions, and delivery potentials, as well as distinguishing them from plant-derived exosomes and highlighting the limitations of the current research. Meanwhile, we elucidated the variations in PDNPs infected by pathogenic microorganisms and emphasized on the biological functions and characteristics of plant virus nanoparticles. After clarifying these problems, it is beneficial to further research on PDNPs in the future and develop their clinical application value.

Potential of Plant Exosome Vesicles from Grapefruit (Citrus × paradisi) and Tomato (Solanum lycopersicum) Juices as Functional Ingredients and Targeted Drug Delivery Vehicles

Plant-derived extracellular vesicles (PEVs) have gained attention as promising bioactive nutraceutical molecules; their presence in common fruit juices has increased their significance because human interaction is inevitable. The goal of this study was to evaluate the potential of PEVs derived from grapefruit and tomato juices as functional ingredients, antioxidant compounds, and delivery vehicles. PEVs were isolated using differential ultracentrifugation and were found to be similar in size and morphology to mammalian exosomes. The yield of grapefruit exosome-like vesicles (GEVs) was higher than that of tomato exosome-like vesicles (TEVs), despite the latter having larger vesicle sizes. Furthermore, the antioxidant activity of GEVs and TEVs was found to be low in comparison to their juice sources, indicating a limited contribution of PEVs to the juice. GEVs showed a higher efficiency in being loaded with the heat shock protein 70 (HSP70) than TEVs, as well as a higher efficiency than TEV and PEV-free HSP70 in delivering HSP70 to glioma cells. Overall, our results revealed that GEVs present a higher potential as functional ingredients present in juice and that they exert the potential to deliver functional molecules to human cells. Although PEVs showed low antioxidant activity, their role in oxidative response in cells should be further addressed.

Tumor-targeted exosomes for delivery of anticancer drugs

Exosomes are small phospholipid bilayer vesicles that are naturally produced by all living cells, both prokaryotes and eukaryotes. The exosomes due to their unique size, reduced immunogenicity, and their ability to mimic synthetic liposomes in carrying various anticancer drugs have been tested as drug delivery vehicles for cancer treatment. An added advantage of developing exosomes as a drug carrier is the ease of manipulating their intraluminal content and their surface modification to achieve tumor-targeted drug delivery. In the past ten-years, there has been an exponential increase in the number of exosome-related studies in cancer. Preclinical studies demonstrate exosomes-mediated delivery of chemotherapeutics, biologicals and natural products produce potent anticancer activity both, in vitro and in vivo. In contrast, the number of exosome-based clinical trials are few due to challenges in the manufacturing and scalability related to large-scale production of exosomes and their storage and stability. Herein, we discuss recent advances in exosome-based drug delivery for cancer treatment in preclinical and clinical studies and conclude with challenges to be overcome for translating a larger number of exosome-based therapies into the clinic.

Plant-derived extracellular vesicles (PDEVs) in nanomedicine for human disease and therapeutic modalities

BACKGROUND

The past few years have witnessed a significant increase in research related to plant-derived extracellular vesicles (PDEVs) in biological and medical applications. Using biochemical technologies, multiple independent groups have demonstrated the important roles of PDEVs as potential mediators involved in cell-cell communication and the exchange of bio-information between species. Recently, several contents have been well identified in PDEVs, including nucleic acids, proteins, lipids, and other active substances. These cargoes carried by PDEVs could be transferred into recipient cells and remarkably influence their biological behaviors associated with human diseases, such as cancers and inflammatory diseases. This review summarizes the latest updates regarding PDEVs and focuses on its important role in nanomedicine applications, as well as the potential of PDEVs as drug delivery strategies to develop diagnostic and therapeutic agents for the clinical management of diseases, especially like cancers.

CONCLUSION

Considering its unique advantages, especially high stability, intrinsic bioactivity and easy absorption, further elaboration on molecular mechanisms and biological factors driving the function of PDEVs will provide new horizons for the treatment of human disease.

Current understanding of plant-derived exosome-like nanoparticles in regulating the inflammatory response and immune system microenvironment

Natural compounds are widely used to prevent and treat various diseases due to their antioxidant and anti-inflammatory effects. As a kind of promising natural compound, plant-derived exosome-like nanoparticles (PELNs) are extracted from multivesicular bodies of various edible plants, including vegetables, foods, and fruits, and mainly regulate the cellular immune response to pathogen attacks. Moreover, PELNs could remarkably interfere with the dynamic imbalance between pro-inflammatory and anti-inflammatory effects, facilitating to maintain the homeostasis of cellular immune microenvironment. PELNs may serve as a better alternative to animal-derived exosomes (ADEs) owing to their widespread sources, cost-effectiveness, and easy accessibility. PELNs can mediate interspecies communication by transferring various cargoes such as proteins, lipids, and nucleic acids from plant cells to mammalian cells. This review summarizes the biogenesis, composition, and classification of exosomes; the common separation, purification, and characterization methods of PELNs, the potential advantages of PELNs over ADEs; and the anti-inflammatory and immunomodulatory functions of PELNs in various diseases including colitis, cancer, and inflammation-associated metabolic diseases. Additionally, the future perspectives of PELNs and the challenges associated with their clinical application are discussed.

Urinary Exosomes: A Promising Biomarker for Disease Diagnosis

Exosomes are nanoscale vesicles derived from endocytosis, formed by fusion of multivesicular bodies with membranes and secreted into the extracellular matrix or body fluids. Many studies have shown that exosomes can be present in a variety of biological fluids, such as plasma, urine, saliva, amniotic fluid, ascites, and sweat, and most types of cells can secrete exosomes. Exosomes play an important role in many aspects of human development, including immunity, cardiovascular diseases, neurodegenerative diseases, and neoplasia. Urine can be an alternative to blood or tissue samples as a potential source of disease biomarkers because of its simple, noninvasive, sufficient, and stable characteristics. Therefore, urinary exosomes have valuable potential for early screening, monitoring disease progression, prognosis, and treatment. The method for isolating urinary exosomes has been perfected, and exosome proteomics is widely used. Therefore, we review the potential use of urinary exosomes for disease diagnosis and summarize the related literature.

Dietary-Derived Exosome-like Nanoparticles as Bacterial Modulators: Beyond MicroRNAs

There is increasing evidence that food is an important factor that influences the composition of the gut microbiota. Usually, all the attention has been focused on nutrients such as lipids, proteins, vitamins, or polyphenols. However, a pivotal role in these processes has been linked to dietary-derived exosome-like nanoparticles (DELNs). While food macro- and micronutrient composition are largely well established, there is considerable interest in these DELNs and their cargoes. In this sense, traditionally, all the attention was focused on the proteins or miRNAs contained in these vesicles. However, it has been shown that DELNs would also carry other bioactive molecules with a key role in regulating biochemical pathways and/or interactions with the host's gut microbiome affecting intracellular communication. Due to the scarce literature, it is necessary to compile the current knowledge about the antimicrobial capacity of DELNs and its possible molecular mechanisms that will serve as a starting point. For this reason, in this review, we highlight the impact of DENLs on different bacteria species modulating the host gut microbiota or antibacterial properties. It could be concluded that DELNs, isolated from both plant and animal foods, exert gut microbiota modulation. However, the presence of miRNA in the vesicle cargoes is not the only one responsible for this effect. Lipids present in the DELNs membrane or small molecules packed in may also be responsible for apoptosis signaling, inhibition, or growth promoters.

Exosomes as natural nanocarrier-based drug delivery system: recent insights and future perspectives

Exosomes are nanosized (size ~ 30-150 nm) natural vesicular structures released from cells by physiological processes or pathological circumstances. Exosomes are growing in popularity as a result of their many benefits over conventional nanovehicles, including their ability to escape homing in the liver or metabolic destruction and their lack of undesired accumulation before reaching their intended targets. Various therapeutic molecules, including nucleic acids, have been incorporated into exosomes by different techniques, many of which have shown satisfactory performance in various diseases. Surface-modified exosomes are a potentially effective strategy, and it increases the circulation time and produces the specific drug target vehicle. In this comprehensive review, we describe composition exosomes biogenesis and the role of exosomes in intercellular signaling and cell-cell communications, immune responses, cellular homeostasis, autophagy, and infectious diseases. In addition, we discuss the role of exosomes as diagnostic markers, and their therapeutic and clinical implications. Furthermore, we addressed the challenges and outstanding developments in exosome research and discuss future perspectives. In addition to the current status of exosomes as a therapeutic carrier, the lacuna in the clinical development lifecycles along with the possible strategies to fill the lacuna have been addressed.

Alternative biological sources for extracellular vesicles production and purification strategies for process scale-up

Extracellular vesicles (EVs) are phospholipidic bi-layer enclosed nanoparticles secreted naturally by all cell types. They are attracting increasing attention in the fields of nanomedicine, nutraceutics and cosmetics as biocompatible carriers for drug delivery, with intrinsic properties beneficial to human health. Scientific work now focuses on developing techniques for isolating EVs that can translate into industrial-scale production and meet rigorous clinical requirements. The science of EVs is ongoing, and many pitfalls must be addressed, such as the requirement for standard, reproducible, inexpensive, and Good Manufacturing Practices (GMP) adherent EV processing techniques. Researchers are exploring the use of alternative sources to EVs derived from mammalian cultures, such as plant EVs, as well as the use of bacteria, algae and milk. Regarding the downstream processing of EVs, many alternative techniques to the ultracentrifugation (UC) protocols most commonly used in the laboratory are emerging. In the context of process scale-up, membrane-based processes for isolation and purification of EVs are the most promising, either as stand-alone processes or in combination with chromatographic techniques. This review discusses current trends on EVs source selection and EVs downstream processing techniques, with a focus on plant-derived EVs and membrane-based techniques for EVs enrichment.

Plant Exosome-like Nanoparticles as Biological Shuttles for Transdermal Drug Delivery

Exosomes act as emerging transdermal drug delivery vehicles with high deformability and excellent permeability, which can be used to deliver various small-molecule drugs and macromolecular drugs and increase the transdermal and dermal retention of drugs, improving the local efficacy and drug delivery compliance. At present, there are many studies on the use of plant exosome-like nanoparticles (PELNVs) as drug carriers. In this review, the source, extraction, isolation, and chemical composition of plant exosomes are reviewed, and the research progress on PELNVs as drug delivery systems in transdermal drug delivery systems in recent years has elucidated the broad application prospect of PELNVs.

Tea leaf-derived exosome-like nanotherapeutics retard breast tumor growth by pro-apoptosis and microbiota modulation

While several artificial nanodrugs have been approved for clinical treatment of breast tumor, their long-term applications are restricted by unsatisfactory therapeutic outcomes, side reactions and high costs. Conversely, edible plant-derived natural nanotherapeutics (NTs) are source-widespread and cost-effective, which have been shown remarkably effective in disease treatment. Herein, we extracted and purified exosome-like NTs from tea leaves (TLNTs), which had an average diameter of 166.9 nm and a negative-charged surface of - 28.8 mV. These TLNTs contained an adequate slew of functional components such as lipids, proteins and pharmacologically active molecules. In vitro studies indicated that TLNTs were effectively internalized by breast tumor cells (4T1 cells) and caused a 2.5-fold increase in the amount of intracellular reactive oxygen species (ROS) after incubation for 8 h. The high levels of ROS triggered mitochondrial damages and arrested cell cycles, resulting in the apoptosis of tumor cells. The mouse experiments revealed that TLNTs achieved good therapeutic effects against breast tumors regardless of intravenous injection and oral administration through direct pro-apoptosis and microbiota modulation. Strikingly, the intravenous injection of TLNTs, not oral administration, yielded obvious hepatorenal toxicity and immune activation. These findings collectively demonstrate that TLNTs can be developed as a promising oral therapeutic platform for the treatment of breast cancer.

Characterization and bioactivity of extracellular vesicles isolated from pomegranate

In the current study, extracellular vesicles from pomegranate juice (PgEVs) were isolated for the first time using size exclusion chromatography (SEC). This method permitted us to obtain highly enriched EV samples without most of the non-EV co-isolated proteins. The characterization of PgEVs through nanoparticle tracking analysis (NTA) and transmission electron microscopy (TEM) allowed the determination of vesicles' concentration/volume, size, and morphology. It was confirmed from the analytical data that PgEVs contain a homogeneous population of vesicles, with a dimension and structure comparable to plant-derived EVs. Proteomic analyses by LC-MS/MS led to the characterization of 131 proteins, and several of them were related commonly to the biogenesis and transport of EVs, and/or proposed as EV markers. PgEVs exerted anti-inflammatory, antioxidant and wound-healing effects when added to the in vitro cultures of monocytic (THP-1) and intestinal (Caco-2) cell lines, respectively.

Plant-derived extracellular vesicles: Recent advancements and current challenges on their use for biomedical applications

Extracellular vesicles (EVs) represent a diverse class of lipid bilayer membrane vesicles released by both animal and plant cells. These ubiquitous vesicles are involved in intercellular communication and transport of various biological cargos, including proteins, lipids, and nucleic acids. In recent years, interest in plant-derived EVs has increased tremendously, as they serve as a scalable and sustainable alternative to EVs derived from mammalian sources. In vitro and in vivo findings have demonstrated that these plant-derived vesicles (PDVs) possess intrinsic therapeutic activities that can potentially treat diseases and improve human health. In addition, PDVs can also act as efficient and biocompatible drug carriers. While preclinical studies have shown promising results, there are still several challenges and knowledge gaps that have to be addressed for the successful translation of PDVs into clinical applications, especially in view of the lack of standardised protocols for material handling and PDV isolation from various plant sources. This review provides the readers with a quick overview of the current understanding and research on PDVs, critically analysing the current challenges and highlighting the immense potential of PDVs as a novel class of therapeutics to treat human diseases. It is expected that this work will guide scientists to address the knowledge gaps currently associated with PDVs and promote new advances in plant-based therapeutic solutions.

Methicillin-Resistant Staphylococcus aureus Membrane Vesicles Inhibit the Proliferation and Induce the Apoptosis of Epithelial Cells

Staphylococcus aureus, or methicillin-resistant Staphylococcus aureus (MRSA), is the predominant pathogen in skin and soft tissue infections (SSTIs), and MRSA membrane vesicles (MVs) play a pivotal role in bacterial pathogenesis and the modulation of the host immune response. We aimed to investigate the interaction between MRSA MVs and epithelial cells. In this study, MVs were isolated from an MRSA culture supernatant using the ELD method, comprising an electrophoretic technique used in combination with a 300 kDa cut-off dialysis bag. The proteomic analysis of the MRSA MVs via mass spectrometry showed that shared and distinct proteins exist in the MVs from clinical MRSA isolates with different genetic backgrounds, such as health-care-associated MRSA (HA-MRSA) and community-associated MRSA (CA-MRSA). These MRSA MVs were found to suppress the proliferation and increase the apoptosis of HaCaT cells. We conducted qPCR array, quantitative real-time PCR (qRT-PCR), and Western blotting (WB) analyses, and the results indicated that BCL2 antagonist/killer 1 (Bak1) may be involved in the apoptosis of HaCaT epithelial cells. Our findings suggest that MRSA MVs inhibit the proliferation and induce the apoptosis of epithelial cells.

Comparison of two isolation methods of tobacco-derived extracellular vesicles, their characterization and uptake by plant and rat cells

Plant extracellular vesicles (pEVs) derived from numerous edible sources gain a lot of attention in recent years, mainly due to the potential to efficiently carry bioactive molecules into mammalian cells. In the present study, we focus on isolation of PDNVs (plant-derived nanovesicles) and pEVs from callus culture and from BY-2 culture of Nicotiana tabacum (tobacco). Tobacco was selected as a source of plant vesicles, as it is commonly used by human, moreover it is a model organism with established techniques for cultivation of explant cultures in vitro. Explant cultures are suitable for the isolation of pEVs in large quantities, due to their fast growth in sterile conditions. As the efficiency of isolation methods varies, we were comparing two methods of isolation. We evaluated biophysical and biochemical properties of plant vesicles, as well as differences between isolates. We encountered difficulties in the form of vesicles aggregation, which is often described in publications focused on mammalian nanovesicles. In an effort to prevent vesicle aggregation, we used trehalose in different stages of isolation. We show tobacco-derived vesicles successfully enter tobacco and mesenchymal cell lines. We observed that tobacco-nanovesicles isolated by different methods incorporated fluorescent dye with different efficiency. The results of our study show tobacco-derived vesicles isolated by various isolation methods are able to enter plant, as well as mammalian cells.

High co-expression of SLC7A11 and GPX4 as a predictor of platinum resistance and poor prognosis in patients with epithelial ovarian cancer

OBJECTIVE

The aim was to assess the expression levels of SLC7A11 and GPX4 in relation to platinum resistance and prognosis in patients with epithelial ovarian cancer (EOC).

DESIGN

A retrospective cohort study.

SETTING

Women's Hospital, Zhejiang University School of Medicine, Hangzhou, China.

POPULATION OR SAMPLE

We included 192 eligible patients from hospital between January 2002 and December 2018.

METHODS

We retrospectively analysed the medical records of patients with EOC. Surgical specimens of EOC were stained for SLC7A11 and GPX4. Survival analysis was performed using the Kaplan-Meier and Cox regression methods.

MAIN OUTCOME MEASURES

Clinical end points include platinum-free interval (PFI), progression-free survival (PFS) and overall survival (OS).

RESULTS

Patients with high co-expression levels of SLC7A11 and GPX4 had a 60-fold higher risk of platinum resistance compared with those with low co-expression (risk ratio, 60.46; 95% confidence interval [CI] 22.76-160.58; p < 0.001). Moreover, high co-expression level of SLC7A11 and GPX4 was an independent prognostic factor for poor OS (p < 0.001, hazard ratio [HR] 4.44, 95% CI, 2.77-7.14) and poor PFS (p < 0.001, HR = 5.73, 95% CI, 3.86-8.73). For in vitro experiments, SLC7A11 and GPX4 expression were both upregulated in platinum-resistant cells compared with their parental ovarian cancer cells, and siRNA-induced SLC7A11 and GPX4 inhibition decreased platinum resistance.

CONCLUSIONS

High expression levels of SLC7A11 and GPX4 are associated with platinum resistance in EOC patients. High co-expression of SLC7A11 and GPX4 may be a significant independent prognostic factor and a potential therapeutic target for platinum resistance in EOC patients.

Organically derived exosomes as carriers of anticancer drugs and imaging agents for cancer treatment

Extracellular vesicles (EVs), is the umbrella term used for different types of vesicles produced by the cells, among which exosomes form the largest group. Exosomes perform intercellular communication by carrying several biologics from donor or parental cells and delivering them to recipient cells. Their unique cargo-carrying capacity has recently been explored for use as delivery vehicles of anticancer drugs and imaging agents. Being naturally produced, exosomes have many advantages over synthetic lipid-based nanoparticles currently being used clinically to treat cancer and other diseases. The finding of the role of exosomes in human diseases has led to numerous preclinical and clinical studies exploring their use as an amenable drug delivery vehicle and a theranostic in cancer diagnosis and treatment. However, there are certain limitations associated with exosomes, with the most important being the selection of the biological source for producing highly biocompatible exosomes on a large scale. This review article explores the various sources from which therapeutically viable exosomes can be isolated for use as drug carriers for cancer treatment. The methods of exosome isolation and the process of loading them with cancer therapeutics and imaging agents are also discussed in the follow-up sections. Finally, the article concludes with future directions for exosome-based applications in cancer diagnosis and treatment.

Bacterial extracellular vesicle applications in cancer immunotherapy

Cancer therapy is undergoing a paradigm shift toward immunotherapy focusing on various approaches to activate the host immune system. As research to identify appropriate immune cells and activate anti-tumor immunity continues to expand, scientists are looking at microbial sources given their inherent ability to elicit an immune response. Bacterial extracellular vesicles (BEVs) are actively studied to control systemic humoral and cellular immune responses instead of using whole microorganisms or other types of extracellular vesicles (EVs). BEVs also provide the opportunity as versatile drug delivery carriers. Unlike mammalian EVs, BEVs have already made it to the clinic with the meningococcal vaccine (Bexsero®). However, there are still many unanswered questions in the use of BEVs, especially for chronic systemically administered immunotherapies. In this review, we address the opportunities and challenges in the use of BEVs for cancer immunotherapy and provide an outlook towards development of BEV products that can ultimately translate to the clinic.

Plant-derived nanovesicles: Current understanding and applications for cancer therapy

Plant-derived vesicles (PDVs) are membranous structures that originate from plant cells and are responsible for multiple physiological and pathological functions. In the last decade, PDVs have gained much attention for their involvement in different biological processes, including intercellular communication and defense response, and recent scientific evidence has opened a new avenue for their applications in cancer treatment. Nevertheless, much remains unknown about these vesicles, and current research remains inconsistent. This review aims to provide a comprehensive introduction to PDVs, from their biological characteristics to purification methods, and to summarize the status of their potential development for cancer therapy.

Carrier-free nanoplatforms from natural plants for enhanced bioactivity

BACKGROUND

Natural plants as well as traditional Chinese medicine have made outstanding contributions to the health and reproduction of human beings and remain the basis and major resource for drug innovation. Carrier-free nanoplatforms completely self-assembled by pure molecules or therapeutic components have attracted increasing attention due to their advantages of improved pharmacodynamics/pharmacokinetics, reduced toxicity, and high drug loading. In recent years, carrier-free nanoplatforms produced by self-assembly from natural plants have contributed to progress in a variety of therapeutic modalities. Notably, these nanoplatforms based on the interactions of components from different natural plants improve efficiency and depress toxicity.

AIM OF REVIEW

In this review, different types of self-assembled nanoplatforms are first summarized, mainly including nanoassemblies of pure small molecules isolated from different plants, extracellular vesicles separated from fresh plants, charcoal nanocomponents obtained from charred plants, and nanoaggregates from plants formulae decoctions. Key Scientific Concepts of Review: We mainly focus on composition, self-assembly mechanisms, biological activity and modes of action. Finally, a future perspective of existing challenges with respect to the clinical application of plant-based carrier-free nanoplatforms is discussed, which may be instructive to further develop effective carrier-free nanoplatforms from natural plants in the future.

Plant extracellular vesicles: A novel bioactive nanoparticle for tumor therapy

Extracellular vesicles are tiny lipid bilayer-enclosed membrane particles, including apoptotic bodies, micro vesicles, and exosomes. Organisms of all life forms can secrete extracellular vesicles into their surrounding environment, which serve as important communication tools between cells and between cells and the environment, and participate in a variety of physiological processes. According to new evidence, plant extracellular vesicles play an important role in the regulation of transboundary molecules with interacting organisms. In addition to carrying signaling molecules (nucleic acids, proteins, metabolic wastes, etc.) to mediate cellular communication, plant cells External vesicles themselves can also function as functional molecules in the cellular microenvironment across cell boundaries. This review introduces the source and extraction of plant extracellular vesicles, and attempts to clarify its anti-tumor mechanism by summarizing the current research on plant extracellular vesicles for disease treatment. We speculate that the continued development of plant extracellular vesicle-based therapeutic and drug delivery platforms will benefit their clinical applications.

Isolation of Aloe saponaria-Derived Extracellular Vesicles and Investigation of Their Potential for Chronic Wound Healing

A chronic wound is caused by a failure to progress through the normal phases of wound repair in an orderly and timely manner. To induce skin regeneration while inhibiting chronic inflammation, numerous natural products, and in particular, plant-derived biomaterials, have been developed. Aloe saponaria, is known to contain flavonoid and phenolic acid compounds with anti-oxidative and anti-inflammatory properties. Here, we isolated extracellular vesicles (EVs) from Aloe saponaria by polyethylene glycol (PEG)-based precipitation and investigated their potential as a therapeutic for chronic wound healing. The Aloe saponaria-derived EVs (AS-EVs) showed no significant cytotoxicity on several cell types, despite a high level of intracellular uptake. When lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages were treated with AS-EVs, significant reductions in the expression of pro-inflammatory genes, such as interleukin-6 and interleukin-1β, were observed. Proliferation and migration of human dermal fibroblasts, as determined by the water-soluble tetrazolium salt-8 and transwell migration assay, respectively, were shown to be promoted by treatment with AS-EVs. It was also demonstrated that AS-EVs enhanced tube formation in human umbilical vein endothelial cells, indicating a stimulatory activity on angiogenesis; one of the crucial steps for effective wound healing. Collectively, our results suggest the potential of AS-EVs as a natural therapeutic for chronic wound healing.

Plant-derived extracellular vesicles as oral drug delivery carriers

Oral administration is one of the most convenient and widely utilized methods of drug administration. However, many drugs were difficult to be administered orally due to their poor oral bioavailability. Designing a safe and effective oral drug delivery system is one of the basic strategies to overcome the poor oral bioavailability. Plant-derived extracellular vesicles (PDEVs) were found in a variety of plants and have similar physical and chemical properties to mammalian EVs. It has been proved that PDEVs can effectively encapsulate hydrophilic and hydrophobic drugs, remain stable in harsh gastrointestinal environments, and cross biological barriers to reach target tissues. Furthermore, the biological activity of PDEVs enables it to play a synergistic therapeutic role with drugs. In addition, the safety and high yield of PDEVs indicate their potential as oral drug carriers. In this review, we introduce the biogenesis, isolation, characterization and drug delivery methods of PDEVs, describe their stability, transport, delivery and therapeutic applications. Finally, the potential and challenges of PDEVs as drug carriers are discussed.

Cucumber-Derived Nanovesicles Containing Cucurbitacin B for Non-Small Cell Lung Cancer Therapy

Purpose

In recent years, a variety of nanoparticles with excellent anticancer and delivery properties have emerged for cancer therapy. However, potential toxicity, high production cost and complex preparation procedures have been obstacles to their use in biomedicine. Here, we obtained cucumber-derived nanovesicles (CDNVs) at high yield and low cost by simple juicing and ultracentrifugation. The anticancer effects of CDNVs were evaluated in vitro and in vivo.

Methods

Transmission electron microscope, nanoparticle tracking analysis and laser particle size analysis were used to characterize the morphology, diameter and zeta potential of CDNVs, respectively. The anticancer effects of CDNVs in vitro were evaluated by MTT and apoptosis assays. The mechanism was further explored by measuring the protein levels of signal transducer and activator of transcription 3 pathway, reactive oxygen species, cell cycle distribution and caspase activity. In-vivo anticancer efficacy was evaluated by measuring tumor volume and weight of mice in three different treatment groups (CDNVs, cucurbitacin B and PBS).

Results

CDNVs inhibited proliferation of human non-small cell lung cancer cells by suppressing signal transducer and activator of transcription 3 activation, generating reactive oxygen species, promoting cell cycle arrest, and activating the caspase pathway. These CDNVs exhibited strong anticancer effects both in vitro and in vivo, and reduced the rate of tumor growth without obvious toxicity to mouse visceral organs. Compared with an equivalent dose of cucurbitacin B, CDNVs exerted stronger anticancer effects in vitro and in vivo.

Conclusion

These results demonstrate that CDNVs suppress tumor growth. This study addresses the development of cancer therapeutic drugs using plant-derived nanovesicles that are cost-efficient, simple to produce in high yields, and provide an alternative approach to drug isolation that may help advance sustainability of medicinal plants.

Anti-inflammatory properties of lemon-derived extracellular vesicles are achieved through the inhibition of ERK/NF-κB signalling pathways

Chronic inflammation is associated with the occurrence of several diseases. However, the side effects of anti-inflammatory drugs prompt the identification of new therapeutic strategies. Plant-derived extracellular vesicles (PDEVs) are gaining increasing interest in the scientific community for their biological properties. We isolated PDEVs from the juice of Citrus limon L. (LEVs) and characterized their flavonoid, limonoid and lipid contents through reversed-phase high-performance liquid chromatography coupled to electrospray ionization quadrupole time-of-flight mass spectrometry (RP-HPLC-ESI-Q-TOF-MS). To investigate whether LEVs have a protective role on the inflammatory process, murine and primary human macrophages were pre-treated with LEVs for 24 h and then were stimulated with lipopolysaccharide (LPS). We found that pre-treatment with LEVs decreased gene and protein expression of pro-inflammatory cytokines, such as IL-6, IL1-β and TNF-α, and reduced the nuclear translocation and phosphorylation of NF-κB in LPS-stimulated murine macrophages. The inhibition of NF-κB activation was associated with the reduction in ERK1-2 phosphorylation. Furthermore, the ability of LEVs to decrease pro-inflammatory cytokines and increase anti-inflammatory molecules was confirmed ex vivo in human primary T lymphocytes. In conclusion, we demonstrated that LEVs exert anti-inflammatory effects both in vitro and ex vivo by inhibiting the ERK1-2/NF-κB signalling pathway.

Extracellular vesicles of cannabis with high CBD content induce anticancer signaling in human hepatocellular carcinoma

Plant-derived extracellular vesicles (EVs) have been the topic of interest in recent years due to their proven therapeutic properties. Intact or manipulated plant EVs have shown antioxidant, anti-inflammatory, and anti-cancerous activities as a result of containing bioactive metabolites and other endogenous molecules. Less is known about the EV efficacy with high levels of bioactive secondary metabolites derived from medicinal or non-edible plants. Numerous data suggest the functionality of Cannabis sativa extract and its phytocannabinoids in cancer treatment. Here, two chemotypes of cannabis with different levels of D-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) were selected. EVs were isolated from each chemotype via differential ultracentrifugation. HPLC analysis was illustrative of the absence of THC in EVs derived from both plants. Therefore, two types of EVs were classified according to their CBD content into high- (H.C-EVs) and low-CBD EVs (L.C-EVs). Electron microscopy and DLS showed both cannabis-derived EVs (CDEVs) can be considered as exosome-like nanovesicles. Cytotoxicity assay showed that H.C-EVs strongly decreased the viability of two hepatocellular carcinoma (HCC) cell lines, HepG2 and Huh-7, in a dose and time-dependent manner compared with L.C-EVs. H.C-EVs had no significant effect on HUVECs normal cell growth. The finding showed that the H.C-EVs arrested the G0/G1 phase in the cell cycle and significantly induced cell death by activating mitochondrial-dependent apoptosis signaling pathways in both HCC cell lines. Altogether, the current study highlights that CDEVs can be an ideal natural vehicle for bioactive phytocannabinoids and a promising strategy in cancer management.

Plant extracellular vesicles and their potential in human health research, the practical approach

Extracellular vesicles are small membrane particles (30-1000 nm) released by Bacteria, Eukaryotes and Archaea. They have been shown to play an important role in intracellular and intercellular communication, within and between kingdoms via transport of bioactive molecules. Thus, they can be involved in altering gene expression and regulation of physiological and pathological processes of the recipient. Their unique properties make extracellular vesicles a perfect candidate vector for targeted drug delivery or a biomarker. For a long time, animal and mainly mammal extracellular vesicles have been used in research. But for plants, there had been speculations about the existence of nanovesicles due to the presence of a cell wall. Today, awareness of plant extracellular vesicles is on the rise and their research has proved they have various functions, such as protein secretion, transport of bioactive molecules or defense against pathogens. Further potential of plant extracellular vesicles is stressed in this review.

Emergence of Edible Plant-Derived Nanovesicles as Functional Food Components and Nanocarriers for Therapeutics Delivery: Potentials in Human Health and Disease

Extracellular vesicles (EVs) are a highly heterogeneous population of membranous particles that are secreted by almost all types of cells across different domains of life, including plants. In recent years, studies on plant-derived nanovesicles (PDNVs) showed that they could modulate metabolic reactions of the recipient cells, affecting (patho)physiology with health benefits in a trans-kingdom manner. In addition to its bioactivity, PDNV has advantages over conventional nanocarriers, making its application promising for therapeutics delivery. Here, we discuss the characteristics of PDNV and highlight up-to-date pre-clinical and clinical evidence, focusing on therapeutic application.

Emerging Role of Edible Exosomes-Like Nanoparticles (ELNs) as Hepatoprotective Agents

Liver diseases are responsible for over 2 million deaths each year and the number is rapidly increasing. There is a strong link between edibles, gut microbiota, liver fat and the liver damage. There are very limited therapeutic options for treatment specifically for Alcoholic liver disease (ALD) and Non-Alcoholic liver disease (NAFLD). Recently, identified Edible Exosomes-like nanoparticles (ELNs) are plant derived membrane bound particles, released by microvesicular bodies for cellular communication and regulate immune responses against many pathogens. Many studies have identified their role as hepatoprotective agent as they carry bioactive material as cargoes which are transferred to recipient cells and affect various biological functions in liver. They are also known to carry specific miRNA, which increases the copy number of beneficial bacteria and the production of lactic acid metabolites in gut and hence restrains from liver injury through portal vein. Few in-vitro studies also have been reported about the anti-inflammatory, anti-oxidant and detoxification properties of ELNs which again protects the liver. The properties such as small size, biocompatibility, stability, low toxicity and non-immunogenicity make ELNs as a better therapeutic option. But, till now, studies on the effect of ELNs as therapeutics are still at its infancy yet promising. Here we discuss about the isolation, characterization, their role in maintaining the gut microbiome and liver homeostasis. Also, we give an outline about the latest advances in ELNs modifications, its biological effects, limitations and we propose the future prospective of ELNs as therapeutics.

Lemon-Derived Extracellular Vesicles Nanodrugs Enable to Efficiently Overcome Cancer Multidrug Resistance by Endocytosis-Triggered Energy Dissipation and Energy Production Reduction

Multidrug resistance remains a great challenge for cancer chemotherapy. Herein, a biomimetic drug delivery system based on lemon-derived extracellular vesicles (EVs) nanodrugs (marked with heparin-cRGD-EVs-doxorubicin (HRED)) is demonstrated, achieving highly efficient overcoming cancer multidrug resistance. The HRED is fabricated by modifying functional heparin-cRGD (HR) onto the surface of EVs and then by loading with doxorubicin (DOX). The obtained HRED enable to effectively enter DOX-resistant cancer cells by caveolin-mediated endocytosis (main), macropinocytosis (secondary), and clathrin-mediated endocytosis (last), exhibiting excellent cellular uptake capacity. The diversified endocytosis capacity of HRED can efficiently dissipate intracellular energy and meanwhile trigger downstream production reduction of adenosine triphosphate (ATP), leading to a significant reduction of drug efflux. Consequently, they show excellent anti-proliferation capacities to DOX-resistant ovarian cancer, ensuring the efficiently overcoming ovarian cancer multidrug resistance in vivo. The authors believe this strategy provides a new strategy by endocytosis triggered-energy dissipation and ATP production reduction to design drug delivery system for overcoming cancer multidrug resistance.

Theragnostic Applications of Mammal and Plant-Derived Extracellular Vesicles: Latest Findings, Current Technologies, and Prospects

The way cells communicate is not fully understood. However, it is well-known that extracellular vesicles (EVs) are involved. Researchers initially thought that EVs were used by cells to remove cellular waste. It is now clear that EVs function as signaling molecules released by cells to communicate with one another, carrying a cargo representing the mother cell. Furthermore, these EVs can be found in all biological fluids, making them the perfect non-invasive diagnostic tool, as their cargo causes functional changes in the cells upon receiving, unlike synthetic drug carriers. EVs last longer in circulation and instigate minor immune responses, making them the perfect drug carrier. This review sheds light on the latest development in EVs isolation, characterization and, application as therapeutic cargo, novel drug loading techniques, and diagnostic tools. We also address the advancement in plant-derived EVs, their characteristics, and applications; since plant-derived EVs only recently gained focus, we listed the latest findings. Although there is much more to learn about, EV is a wide field of research; what scientists have discovered so far is fascinating. This paper is suitable for those new to the field seeking to understand EVs and those already familiar with it but wanting to review the latest findings.

Focusing on Future Applications and Current Challenges of Plant Derived Extracellular Vesicles

Plant derived extracellular vesicles (EVs) are nano-sized membranous vesicles released by plant cells, which contain lipids, proteins, nucleic acids and specific pharmacologically active substances. They are safe, widely available and expediently extractive. They have gratifyingly biological activity against inflammation, cancer, bacteria and oxidative aging, especially for the prevention or treatment of colitis, cancer, alcoholic liver, and COVID-19. In addition, as natural drug carriers, plant derived EVs have the potential to target the delivery of small molecule drugs and nucleic acid through oral, transdermal, injection. With the above advantages, plant derived EVs are expected to have excellent strong competitiveness in clinical application or preventive health care products in the future. We comprehensively reviewed the latest separation methods and physical characterization techniques of plant derived EVs, summarized the application of them in disease prevention or treatment and as a new drug carrier, and analyzed the clinical application prospect of plant derived EVs as a new drug carrier in the future. Finally, the problems hindering the development of plant derived EVs at present and consideration of the standardized application of them are discussed.

The Potentiality of Plant-Derived Nanovesicles in Human Health-A Comparison with Human Exosomes and Artificial Nanoparticles

Research in science and medicine is witnessing a massive increases in literature concerning extracellular vesicles (EVs). From a morphological point of view, EVs include extracellular vesicles of a micro and nano sizes. However, this simplistic classification does not consider both the source of EVs, including the cells and the species from which Evs are obtained, and the microenvironmental condition during EV production. These two factors are of crucial importance for the potential use of Evs as therapeutic agents. In fact, the choice of the most suitable Evs for drug delivery remains an open debate, inasmuch as the use of Evs of human origin may have at least two major problems: (i) autologous Evs from a patient may deliver dangerous molecules; and (ii) the production of EVs is also limited to cell factory conditions for large-scale industrial use. Recent literature, while limited to only a few papers, when compared to the papers on the use of human EVs, suggests that plant-derived nanovesicles (PDNV) may represent a valuable tool for extensive use in health care.

Plant-Derived Exosomes as A Drug-Delivery Approach for the Treatment of Inflammatory Bowel Disease and Colitis-Associated Cancer

Inflammatory bowel disease (IBD) is a chronic recurrent intestinal disease and includes Crohn’s disease (CD) and ulcerative colitis (UC). Due to the complex etiology of colitis, the current treatments of IBD are quite limited and are mainly concentrated on the remission of the disease. In addition, the side effects of conventional drugs on the body cannot be ignored. IBD also has a certain relationship with colitis-associated cancer (CAC), and inflammatory cells can produce a large number of tumor-promoting cytokines to promote tumor progression. In recent years, exosomes from plants have been found to have the ability to load drugs to target the intestine and have great potential for the treatment of intestinal diseases. This plant-derived exosome-targeting delivery system can load chemical or nucleic acid drugs and deliver them to intestinal inflammatory sites stably and efficiently. This review summarizes the pathophysiological characteristics of IBD and CAC as well as the application and prospect of plant exosomes in the treatment of IBD and CAC.

Induction of apoptosis in human colorectal cancer cells by nanovesicles from fingerroot (Boesenbergia rotunda (L.) Mansf.)

Colorectal cancer is the leading cause of cancer-related deaths worldwide, warranting the urgent need for a new treatment option. Plant-derived nanovesicles containing bioactive compounds represent new therapeutic avenues due to their unique characteristics as natural nanocarriers for bioactive molecules with therapeutic effects. Recent evidence has revealed potential anticancer activity of bioactive compounds from Boesenbergia rotunda (L.) Mansf. (fingerroot). However, the effect and the underlying mechanisms of fingerroot-derived nanovesicles (FDNVs) against colorectal cancer are still unknown. We isolated the nanovesicles from fingerroot and demonstrated their anticancer activity against two colorectal cancer cell lines, HT-29 and HCT116. The IC50 values were 63.9 ± 2.4, 57.8 ± 4.1, 47.8 ± 7.6 μg/ml for HT-29 cells and 57.7 ± 6.6, 47.2 ± 5.2, 34 ± 2.9 μg/ml for HCT116 cells at 24, 48, and 72 h, respectively. Interestingly, FDNVs were not toxic to a normal colon epithelial cell line, CCD 841 CoN. FDNVs exhibited selective uptake by the colorectal cancer cell lines but not the normal colon epithelial cell line. Moreover, dose- and time-dependent FDNV-induced apoptosis was only observed in the colorectal cancer cell lines. In addition, reactive oxygen species levels were substantially increased in colorectal cancer cells, but total glutathione decreased after treatment with FDNVs. Our results show that FDNVs exhibited selective anticancer activity in colorectal cancer cell lines via the disruption of intracellular redox homeostasis and induction of apoptosis, suggesting the utility of FDNVs as a novel intervention for colorectal cancer patients.

Integrated therapy platform of exosomal system: hybrid inorganic/organic nanoparticles with exosomes for cancer treatment

Recent studies have found that exosomes or extracellular vehicles (EVs) are associated with cancer metastasis, disease progression, diagnosis, and treatment, leading to a rapidly emerging area of exocrine vesicle research. Relying on the superior targeting function and bio-compatibility of exosomes, researchers have been able to deliver drugs to cancer stem cells deep within tumors in mouse models. Despite significant efforts made in this relatively new field of exosome research, progress has been held back by challenges such as inefficient separation methods, difficulties in characterization/tracking, and a lack of specific biomarkers. Therefore, current researches are devoted to combining nanomaterials with exosomes to improve these shortcomings. Adding inorganic/organic nanoparticles such as artificial liposomes and iron oxide can bring more drug options and various fluorescent or magnetic diagnostic possibilities to the exosome system. Moreover, the applications of exosomes need to be further evaluated under actual physiological conditions. This review article highlights the potential of exosome-biomimetic nanoparticles for their use as drug carriers to improve the efficacy of anticancer therapy.

Plant-RNA in Extracellular Vesicles: The Secret of Cross-Kingdom Communication

The release of extracellular vesicles (EVs) is a common language, used by living organisms from different kingdoms as a means of communication between them. Extracellular vesicles are lipoproteic particles that contain many biomolecules, such as proteins, nucleic acids, and lipids. The primary role of EVs is to convey information to the recipient cells, affecting their function. Plant-derived extracellular vesicles (PDEVs) can be isolated from several plant species, and the study of their biological properties is becoming an essential starting point to study cross-kingdom communication, especially between plants and mammalians. Furthermore, the presence of microRNAs (miRNAs) in PDEVs represents an interesting aspect for understanding how PDEVs can target the mammalian genes involved in pathological conditions such as cancer, inflammation, and oxidative stress. In particular, this review focuses on the history of PDEVs, from their discovery, to purification from various matrices, and on the functional role of PDEV-RNAs in cross-kingdom interactions. It is worth noting that miRNAs packaged in PDEVs can be key modulators of human gene expression, representing potential therapeutic agents.

Technology insight: Plant-derived vesicles-How far from the clinical biotherapeutics and therapeutic drug carriers?

Within the past decades, extracellular vesicles (EVs) have emerged as important mediators of intercellular communication in both prokaryotes and higher eukaryotes to regulate a diverse range of biological processes. Besides EVs, exosome-like nanoparticles (ELNs) derived from plants were also emerging. Comparing to EVs, ELNs are source-widespread, cost-effective and easy to obtain. Their definite activities can be utilized for potential prevention/treatment of an abundance of diseases, including metabolic syndrome, cancer, colitis, alcoholic hepatitis and infectious diseases, which highlights ELNs as promising biotherapeutics. In addition, the potential of ELNs as natural or engineered drug carriers is also attractive. In this review, we tease out the timeline of plant EVs and ELNs, introduce the arising separation, purification and characterization techniques, state the stability and transport manner, discuss the therapeutic opportunities as well as the potential as novel drug carriers. Finally, the challenges and the direction of efforts to realize the clinical transformation of ELNs are also discussed.

Characterizing Kaempferia parviflora extracellular vesicles, a nanomedicine candidate

Plant-derived extracellular vesicles (EVs) are a promising candidate for nanomedicine delivery due to their bioactive cargos, high biocompatibility to human cells, biodegradability, low cytotoxicity, and potential for large-scale production. However, the research on EVs derived from medicinal plants is very limited. In this study, Kaempferia parviflora extracellular vesicles (KPEVs) were isolated by differential and sucrose density gradient centrifugation, and their size, morphology, and surface charge were characterized using transmission electron microscopy and dynamic light scattering. The biological properties of KPEVs, including their bioactive compound composition, gastric uptake, cytotoxicity, acid tolerance, and storage stability, were also examined. In addition, KPEVs had an average and uniform size of 200–300 nm and a negative surface charge of 14.7 ± 3.61 mV. Moreover, 5,7-dimethoxyflavone, the major bioactive compound of KP, was packaged into KPEVs. Meanwhile, KPEVs were resistant to gastric digestion and stably maintained at −20°C and −80°C for 8 weeks with no freeze-thaw cycle. The lipid hydrolysis during EVs storage at room temperature and 4°C were also demonstrated for the first time. Furthermore, the labeled KPEVs were internalized into adenocarcinoma gastric cells, and the cell viability was reduced in a dose-dependent manner, according to the results of the thiazolyl blue tetrazolium assay. Our study supports the potential application of KPEVs as a vehicle for anticancer or oral drugs.

Extracellular Vesicles Derived From Citrus sinensis Modulate Inflammatory Genes and Tight Junctions in a Human Model of Intestinal Epithelium

It is widely acknowledged that mammalian exosomes (or extracellular vesicles), have a key role in intercellular communication, owing to the presence of various bioactive molecules such as lipids, proteins, and microRNAs within their inner compartment. Most recently, the discovery of extracellular vesicles isolated from edible plants (such as vegetables and fruits) and their similarity in terms of size and content with exosomes has opened new perspectives on possible intercellular communication and regulation of important biological processes in which these vesicles are involved. It is also well-known that a balanced diet rich of fruits and vegetables (i.e., the Mediterranean diet) can contribute to maintain a “healthy gut” by preserving the intestinal epithelial barrier integrity and avoid that inflammatory stimuli that can alter homeostasis. In our study, we optimized a method to isolate extracellular vesicles from the orange juice (Citrus sinensis) (CS-EVs), and we characterized their morphology and behavior when in contact with the intestinal epithelium. We showed that CS-EVs are stable in a simulated gastrointestinal environment and are absorbed by intestinal cells without toxic effects, as expected. Furthermore, we demonstrated that CS-EVs can alter the gene expression of several genes involved in inflammation (i.e., ICAM1 and HMOX-1) and tight junctions (i.e., OCLN, CLDN1, and MLCK), contributing to limit inflammatory stimuli and restore a functional barrier by increasing the tight junction OCLN protein. Therefore, our study emphasizes the relevant role of fruit-derived extracellular vesicles in modulating important biological processes and maintaining a healthy intestinal epithelium, ultimately promoting human health and well-being.

Immunostimulatory Potential of Extracellular Vesicles Isolated from an Edible Plant, Petasites japonicus, via the Induction of Murine Dendritic Cell Maturation

Extracellular vesicles (EVs) have recently been isolated from different plants. Plant-derived EVs have been proposed as potent therapeutics and drug-delivery nanoplatforms for delivering biomolecules, including proteins, RNAs, DNAs, and lipids. Herein, Petasites japonicus-derived EVs (PJ-EVs) were isolated through a series of centrifugation steps and characterized using dynamic light scattering and transmission electron microscopy. Immunomodulatory effects of PJ-EVs were assessed using dendritic cells (DCs). PJ-EVs exhibited a spherical morphology with an average size of 122.6 nm. They induced the maturation of DCs via an increase in the expression of surface molecules (CD80, CD86, MHC-I, and MHC-II), production of Th1-polarizing cytokines (TNF-α and IL-12p70), and antigen-presenting ability; however, they reduced the antigen-uptake ability. Furthermore, maturation of DCs induced by PJ-EVs was dependent on the activation and phosphorylation of MAPK and NF-κB signal pathways. Notably, PJ-EV-treated DCs strongly induced the proliferation and differentiation of naïve T cells toward Th1-type T cells and cytotoxic CD8⁺ T cells along with robust secretion of IFN-γ and IL-2. In conclusion, our study indicates that PJ-EVs can be potent immunostimulatory candidates with an ability of strongly inducing the maturation of DCs.

Bitter melon derived extracellular vesicles enhance the therapeutic effects and reduce the drug resistance of 5-fluorouracil on oral squamous cell carcinoma

Background

Plant-derived extracellular vesicles (PDEVs) have been exploited for cancer treatment with several benefits. Bitter melon is cultivated as a vegetable and folk medicine with anticancer and anti-inflammatory activities. 5-Fluorouracil (5-FU) is widely used for cancer treatment. However, 5-FU-mediated NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammation activation induced the resistance of oral squamous cell carcinoma (OSCC) cells to 5-FU. In this study, we explored the potential of bitter melon-derived extracellular vesicles (BMEVs) for enhancing the therapeutic efficacy and reduce the resistance of OSCC to 5-FU.

Results

Herein, we demonstrate that bitter melon derived extracellular vesicles (BMEVs), in addition to their antitumor activity against OSCC have intrinsic anti-inflammatory functions. BMEVs induced S phase cell cycle arrest and apoptosis. Apoptosis induction was dependent on reactive oxygen species (ROS) production and JUN protein upregulation, since pretreatment with N-acetyl cysteine or catechin hydrate could prevent apoptosis and JUN accumulation, respectively. Surprisingly, BMEVs significantly downregulated NLRP3 expression, although ROS plays a central role in NLRP3 activation. We further assessed the underlying molecular mechanism and proposed that the RNAs of BMEVs, at least in part, mediate anti-inflammatory bioactivity. In our previous studies, NLRP3 activation contributed to the resistance of OSCC cells to 5-FU. Our data clearly indicate that BMEVs could exert a remarkable synergistic therapeutic effect of 5-FU against OSCC both in vitro and in vivo. Most notably, NLRP3 downregulation reduced the resistance of OSCC to 5-FU.

Conclusions

Together, our findings demonstrate a novel approach to enhance the therapeutic efficacy and reduce the drug resistance of cancer cells to chemotherapeutic agents, which provides proof-of-concept evidence for the future development of PDEVs-enhanced therapy.

Graphic Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s12951-021-00995-1.

Identification of Tomato Infecting Viruses That Co-Isolate with Nanovesicles Using a Combined Proteomics and Electron-Microscopic Approach

Plant-derived nanovesicles (NVs) have attracted interest due to their anti-inflammatory, anticancer and antioxidative properties and their efficient uptake by human intestinal epithelial cells. Previously we showed that tomato (Solanum lycopersicum L.) fruit is one of the interesting plant resources from which NVs can be obtained at a high yield. In the course of the isolation of NVs from different batches of tomatoes, using the established differential ultracentrifugation or size-exclusion chromatography methods, we occasionally observed the co-isolation of viral particles. Density gradient ultracentrifugation (gUC), using sucrose or iodixanol gradient materials, turned out to be efficient in the separation of NVs from the viral particles. We applied cryogenic transmission electron microscopy (cryo-TEM), scanning electron microscopy (SEM) for the morphological assessment and LC-MS/MS-based proteomics for the protein identification of the gradient fractions. Cryo-TEM showed that a low-density gUC fraction was enriched in membrane-enclosed NVs, while the high-density fractions were rich in rod-shaped objects. Mass spectrometry-based proteomic analysis identified capsid proteins of tomato brown rugose fruit virus, tomato mosaic virus and tomato mottle mosaic virus. In another batch of tomatoes, we isolated tomato spotted wilt virus, potato virus Y and southern tomato virus in the vesicle sample. Our results show the frequent co-isolation of plant viruses with NVs and the utility of the combination of cryo-TEM, SEM and proteomics in the detection of possible viral contamination.

Extracellular Vesicles from Plants: Current Knowledge and Open Questions

The scientific interest in the beneficial properties of natural substances has been recognized for decades, as well as the growing attention in extracellular vesicles (EVs) released by different organisms, in particular from animal cells. However, there is increasing interest in the isolation and biological and functional characterization of these lipoproteic structures in the plant kingdom. Similar to animal vesicles, these plant-derived extracellular vesicles (PDEVs) exhibit a complex content of small RNAs, proteins, lipids, and other metabolites. This sophisticated composition enables PDEVs to be therapeutically attractive. In this review, we report and discuss current knowledge on PDEVs in terms of isolation, characterization of their content, biological properties, and potential use as drug delivery systems. In conclusion, we outline controversial issues on which the scientific community shall focus the attention shortly.

Plant-Derived Nano and Microvesicles for Human Health and Therapeutic Potential in Nanomedicine

Plants produce different types of nano and micro-sized vesicles. Observed for the first time in the 60s, plant nano and microvesicles (PDVs) and their biological role have been inexplicably under investigated for a long time. Proteomic and metabolomic approaches revealed that PDVs carry numerous proteins with antifungal and antimicrobial activity, as well as bioactive metabolites with high pharmaceutical interest. PDVs have also been shown to be also involved in the intercellular transfer of small non-coding RNAs such as microRNAs, suggesting fascinating mechanisms of long-distance gene regulation and horizontal transfer of regulatory RNAs and inter-kingdom communications. High loading capacity, intrinsic biological activities, biocompatibility, and easy permeabilization in cell compartments make plant-derived vesicles excellent natural or bioengineered nanotools for biomedical applications. Growing evidence indicates that PDVs may exert anti-inflammatory, anti-oxidant, and anticancer activities in different in vitro and in vivo models. In addition, clinical trials are currently in progress to test the effectiveness of plant EVs in reducing insulin resistance and in preventing side effects of chemotherapy treatments. In this review, we concisely introduce PDVs, discuss shortly their most important biological and physiological roles in plants and provide clues on the use and the bioengineering of plant nano and microvesicles to develop innovative therapeutic tools in nanomedicine, able to encompass the current drawbacks in the delivery systems in nutraceutical and pharmaceutical technology. Finally, we predict that the advent of intense research efforts on PDVs may disclose new frontiers in plant biotechnology applied to nanomedicine.

Application of Emerging Plant-Derived Nanoparticles as a Novel Approach for Nano-Drug Delivery Systems

Nanotechnology has enabled the delivery of small molecular drugs packaged in nanosized vesicles to the target tissues. Plant-Derived Nanoparticles (PDNPs) are vesicles with natural origin and unique properties. These nanoparticles have several advantages over synthetic exosomes and liposomes. They provide bioavailability and biodistribution of therapeutic agents when delivered into different tissues. These nanoparticles can be modified according to the specificity of their functions in target tissues. When PDNPs are internalized, they can induce stem cells proliferation, reduce colitis injury, activate intrinsic and extrinsic apoptosis pathways, and inhibit tumor growth and progression. These properties make them potential drug delivery systems in targeting diseased tissues, such as inflammatory regions and different cancers.

Modern isolation and separation techniques for extracellular vesicles

Extracellular vesicles (EVs) are heterogenous membrane-bound vesicles released from various origins. EVs play a crucial role in cellular communication and mediate several physiological and pathological processes, highlighting their potential therapeutic and diagnostic applications. Due to the rapid increase in interests and needs to elucidate EV properties and functions, numerous isolation and separation approaches for EVs have been developed to overcome limitations of conventional techniques, such as ultracentrifugation. This review focuses on recently emerging and modern EV isolation and separation techniques, including size-, charge-, and affinity-based techniques while excluding ultracentrifugation and precipitation-based techniques due to their multiple limitations. The advantages and drawbacks of each technique are discussed together with insights into their applications. Emerging approaches all share similar features in terms of being time-effective, easy-to-operate, and capable of providing EVs with suitable and desirable purity and integrity for applications of interest. Combination and hyphenation of techniques have been used for EV isolation and separation to yield EVs with the best quality. The most recent development using an automated on-line system including selective affinity-based trapping unit and asymmetrical flow field-flow fractionation allows reliable isolation and fractionation of EV subpopulations from human plasma.

The Impact of Herbal Infusion Consumption on Oxidative Stress and Cancer: The Good, the Bad, the Misunderstood

The release of reactive oxygen species (ROS) and oxidative stress is associated with the development of many ailments, including cardiovascular diseases, diabetes and cancer. The causal link between oxidative stress and cancer is well established and antioxidants are suggested as a protective mechanism against cancer development. Recently, an increase in the consumption of antioxidant supplements was observed globally. The main sources of these antioxidants include fruits, vegetables, and beverage. Herbal infusions are highly popular beverages consumed daily for different reasons. Studies showed the potent antioxidant effects of plants used in the preparation of some herbal infusions. Such herbal infusions represent an important source of antioxidants and can be used as a dietary protection against cancer. However, uncontrolled consumption of herbal infusions may cause toxicity and reduced antioxidant activity. In this review, eleven widely consumed herbal infusions were evaluated for their antioxidant capacities, anticancer potential and possible toxicity. These herbal infusions are highly popular and consumed as daily drinks in different countries. Studies discussed in this review will provide a solid ground for researchers to have better understanding of the use of herbal infusions to reduce oxidative stress and as protective supplements against cancer development.