Evidence of transfer of miRNAs from the diet to the blood still inconclusive

Evidence of Cross-Kingdom Gene Regulation by Plant MicroRNAs and Possible Reasons for Inconsistencies

The debate on whether cross-kingdom gene regulation by orally acquired plant miRNAs is possible has been ongoing for nearly 10 years without a conclusive answer. In this study, we categorized plant miRNAs into different groups, namely, extracellular vesicle (EV)-borne plant miRNAs, extracted plant miRNAs, herbal decoction-borne plant miRNAs, synthetic plant miRNA mimics, and plant tissue/juice-borne plant miRNAs. This categorization aimed to simplify the analysis and address the question more specifically. Our evidence suggests that EV-borne plant miRNAs, extracted plant miRNAs, herbal decoction-borne plant miRNAs, and synthetic plant miRNA mimics consistently facilitate cross-kingdom gene regulation. However, the results regarding the cross-kingdom gene regulation by plant tissue- and juice-borne plant miRNAs are inconclusive. This inconsistency may be due to variations in study methods, a low absorption rate of miRNAs and the selective absorption of plant miRNAs in the gastrointestinal tract. Overall, it is deduced that cross-kingdom gene regulation by orally acquired plant miRNAs can occur under certain circumstances, depending on factors such as the types of plant miRNAs, the delivery mechanism, and their concentrations in the plant.

Dietary intervention for tertiary prevention in head and neck squamous cell carcinoma survivors: clinical and translational results of a randomized phase II trial

Background

There is a strong need for preventive approaches to reduce the incidence of recurrence, second cancers, and late toxicities in head and neck squamous cell carcinoma (HNSCC) survivors. We conducted a randomized controlled trial (RCT) to assess a dietary intervention as a non-expensive and non-toxic method of tertiary prevention in HNSCC survivors.

Methods

Eligible participants were disease-free patients with HNSCC in follow-up after curative treatments. Subjects were randomized 1:1 to receive a highly monitored dietary intervention plus the Word Cancer Research Fund/American Institute for Cancer Research recommendations for cancer prevention (intervention arm) or standard-of-care recommendations (control arm). The planned sample size for the event-free survival evaluation (primary endpoint) was not reached, and the protocol was amended in order to investigate the clinical (nutritional and quality-of-life questionnaires) and translational study [plasma-circulating food-related microRNAs (miRNAs)] as main endpoints, the results of which are reported herein.

Results

One hundred patients were screened, 94 were randomized, and 89 were eligible for intention-to-treat analysis. Median event-free survival was not reached in both arms. After 18 months, nutritional questionnaires showed a significant increase in Recommended Food Score (p = 0.04) in the intervention arm vs. control arm. The frequency of patients with and without a clinically meaningful deterioration or improvement of the C30 global health status in the two study arms was similar. Food-derived circulating miRNAs were identified in plasma samples at baseline, with a significant difference among countries.

Conclusion

This RCT represented the first proof-of-principle study, indicating the feasibility of a clinical study based on nutritional and lifestyle interventions in HNSCC survivors. Subjects receiving specific counseling increased the consumption of the recommended foods, but no relevant changes in quality of life were recorded between the two study arms. Food-derived plasma miRNA might be considered promising circulating dietary biomarkers.

Dietary Epigenetic Modulators: Unravelling the Still-Controversial Benefits of miRNAs in Nutrition and Disease

In the context of nutrient-driven epigenetic alterations, food-derived miRNAs can be absorbed into the circulatory system and organs of recipients, especially humans, and potentially contribute to modulating health and diseases. Evidence suggests that food uptake, by carrying exogenous miRNAs (xenomiRNAs), regulates the individual miRNA profile, modifying the redox homeostasis and inflammatory conditions underlying pathological processes, such as type 2 diabetes mellitus, insulin resistance, metabolic syndrome, and cancer. The capacity of diet to control miRNA levels and the comprehension of the unique characteristics of dietary miRNAs in terms of gene expression regulation show important perspectives as a strategy to control disease susceptibility via epigenetic modifications and refine the clinical outcomes. However, the absorption, stability, availability, and epigenetic roles of dietary miRNAs are intriguing and currently the subject of intense debate; additionally, there is restricted knowledge of their physiological and potential side effects. Within this framework, we provided up-to-date and comprehensive knowledge on dietary miRNAs' potential, discussing the latest advances and controversial issues related to the role of miRNAs in human health and disease as modulators of chronic syndromes.

Comparison of goat and cow milk-derived extracellular vesicle miRNomes

miRNAs present in milk are mainly found in extracellular vesicles (EVs), which are nanosized membrane vesicles released by most of the cell types to ensure intercellular communication. The majority of the studies performed so far on these vesicles have been conducted on human and cow's milk and focused on their miRNA content. The objectives of this study were to profile the miRNA content of purified EVs from five healthy goats and to compare their miRNome to those obtained from five healthy cows, at an early stage of lactation. EV populations were morphologically characterized using Transmission Electron Microscopy and Nanoparticle Tracking Analysis. The presence of EV protein markers checked by Western blotting and the absence of contamination of preparations by milk proteins. The size distribution and concentration of bovine and goat milk-derived EVs were similar. RNA-sequencing were performed, and all sequences were mapped to the cow genome identifying a total of 295 miRNAs. This study reports for the first-time a goat miRNome from milk EVs and its validation using cow miRNomes.

MicroRNAs from Holarrhena pubescens stems: Identification by small RNA Sequencing and their Potential Contribution to Human Gene Targets

Holarrhena pubescens is an effective medicinal plant from the Apocynaceae family, widely distributed over the Indian subcontinent and extensively used by Ayurveda and ethno-medicine systems without apparent side effects. We postulated that miRNAs, endogenous non-coding small RNAs that regulate gene expression at the post-transcriptional level, may, after ingestion into the human body, contribute to the medicinal properties of plants of this species by inducing regulated human gene expression to modulate. However, knowledge is scarce about miRNA in Holarrhena. In addition, to test the hypothesis on the potential pharmacological properties of miRNA, we performed a high-throughput sequencing analysis using the Next Generation Sequencing Illumina platform; 42,755,236 raw reads have been generated from H. pubescens stems from a library of small RNA isolated, identifying 687 known and 50 new miRNAs led. The novel H. pubescens miRNAs were predicted to regulate specific human genes, and subsequent annotations of gene functions suggested a possible role in various biological processes and signaling pathways, such as Wnt, MAPK, PI3K-Akt, and AMPK signaling pathways and endocytosis. The association of these putative targets with many diseases, including cancer, congenital malformations, nervous system disorders, and cystic fibrosis, has been demonstrated. The top hub proteins STAT3, MDM2, GSK3B, NANOG, IGF1, PRKCA, SNAP25, SRSF1, HTT, and SNCA show their interaction with human diseases, including cancer and cystic fibrosis. To our knowledge, this is the first report of uncovering H. pubescens miRNAs based on high-throughput sequencing and bioinformatics analysis. This study has provided new insight into a potential cross-species control of human gene expression. The potential for miRNA transfer should be evaluated as one possible mechanism of action to account for the beneficial properties of this valuable species.

A Brief History of Glandular Therapy: More Than Just Thyroid

In the late 1800s, treatment with thyroid extract caused dramatic improvement in patients with myxedema. Shortly thereafter, multiple other glandular extracts became available, both individually and in combinations. Their use gradually fell into disfavor, partly due to overpromotion by the manufacturers. The history of the use of thyroid, pancreatic, adrenal, thymus and liver extracts suggests that glandular extracts can be beneficial, especially when potential mechanisms of action and methods of preparation are considered.

Cross-Kingdom Regulation of Plant-Derived miRNAs in Modulating Insect Development

MicroRNAs (miRNAs), a class of non-coding small RNAs, are crucial regulatory factors in plants and animals at the post-transcriptional level. These tiny molecules suppress gene expression by complementary oligonucleotide binding to sites in the target messenger. Recently, the discovery of plant-derived miRNAs with cross-kingdom abilities to regulate gene expression in insects has promoted exciting discussion, although some controversies exist regarding the modulation of insect development by plant-derived miRNAs. Here, we review current knowledge about the mechanisms of miRNA biogenesis, the roles of miRNAs in coevolution between insects and plants, the regulation of insect development by plant-derived miRNAs, the cross-kingdom transport mechanisms of plant-derived miRNAs, and cross-kingdom regulation. In addition, the controversy regarding the modulation of insect development by plant-derived miRNAs also was discussed. Our review provides new insights for understanding complex plant-insect interactions and discovering new strategies for pest management and even crop genetic improvement.

Extracellular Vesicles—Oral Therapeutics of the Future

Considered an artifact just after discovery, the possibility of oral delivery of extracellular vesicles (EVs) and their functional cargos has recently gained much research attention. EVs from various sources, including edible plants, milk, bacteria and mammalian cells, have emerged as a platform for miRNA and drug delivery that seem to induce the expected immune effects locally and in distant tissues after oral administration. Such a possibility greatly expands the clinical applicability of EVs. The present review summarizes research findings that either support or deny the biological/therapeutical activity of orally administered EVs and their role in cross-species and cross-kingdom signaling.

Exosome Carrier Effects; Resistance to Digestion in Phagolysosomes May Assist Transfers to Targeted Cells; II Transfers of miRNAs Are Better Analyzed via Systems Approach as They Do Not Fit Conventional Reductionist Stoichiometric Concepts

Carrier effects of extracellular vesicles (EV) like exosomes refer to properties of the vesicles that contribute to the transferred biologic effects of their contents to targeted cells. This can pertain to ingested small amounts of xenogeneic plant miRNAs and oral administration of immunosuppressive exosomes. The exosomes contribute carrier effects on transfers of miRNAs by contributing both to the delivery and the subsequent functional intracellular outcomes. This is in contrast to current quantitative canonical rules that dictate just the minimum copies of a miRNA for functional effects, and thus successful transfers, independent of the EV carrier effects. Thus, we argue here that transfers by non-canonical minute quantities of miRNAs must consider the EV carrier effects of functional low levels of exosome transferred miRNA that may not fit conventional reductionist stoichiometric concepts. Accordingly, we have examined traditional stoichiometry vs. systems biology that may be more appropriate for delivered exosome functional responses. Exosome carrier properties discussed include; their required surface activating interactions with targeted cells, potential alternate targets beyond mRNAs, like reaching a threshold, three dimensional aspects of the RNAs, added EV kinetic dynamic aspects making transfers four dimensional, and unique intracellular release from EV that resist intracellular digestion in phagolysosomes. Together these EV carrier considerations might allow systems analysis. This can then result in a more appropriate understanding of transferred exosome carrier-assisted functional transfers. A plea is made that the miRNA expert community, in collaboration with exosome experts, perform new experiments on molecular and quantitative miRNA functional effects in systems that include EVs, like variation in EV type and surface constituents, delivery, dose and time to hopefully create more appropriate and truly current canonical concepts of the consequent miRNA functional transfers by EVs like exosomes.

Immunomodulatory Properties of Human Breast Milk: MicroRNA Contents and Potential Epigenetic Effects

Infants who are exclusively breastfed in the first six months of age receive adequate nutrients, achieving optimal immune protection and growth. In addition to the known nutritional components of human breast milk (HBM), i.e., water, carbohydrates, fats and proteins, it is also a rich source of microRNAs, which impact epigenetic mechanisms. This comprehensive work presents an up-to-date overview of the immunomodulatory constituents of HBM, highlighting its content of circulating microRNAs. The epigenetic effects of HBM are discussed, especially those regulated by miRNAs. HBM contains more than 1400 microRNAs. The majority of these microRNAs originate from the lactating gland and are based on the remodeling of cells in the gland during breastfeeding. These miRNAs can affect epigenetic patterns by several mechanisms, including DNA methylation, histone modifications and RNA regulation, which could ultimately result in alterations in gene expressions. Therefore, the unique microRNA profile of HBM, including exosomal microRNAs, is implicated in the regulation of the genes responsible for a variety of immunological and physiological functions, such as FTO, INS, IGF1, NRF2, GLUT1 and FOXP3 genes. Hence, studying the HBM miRNA composition is important for improving the nutritional approaches for pregnancy and infant's early life and preventing diseases that could occur in the future. Interestingly, the composition of miRNAs in HBM is affected by multiple factors, including diet, environmental and genetic factors.

Small RNA sequencing and identification of papaya (Carica papaya L.) miRNAs with potential cross-kingdom human gene targets

Several studies have demonstrated potential role of plant-derived miRNAs in cross-kingdom species relationships by transferring into non-plant host cells to regulate certain host cellular functions. How nutrient-rich plants regulate host cellular functions, which in turn alleviate physiological and disease conditions in the host remains to be explored in detail. This computational study explores the potential targets, putative role, and functional implications of miRNAs derived from Carica papaya L., one of the most cultivated tropical crops in the world and a rich source of phytochemicals and enzymes, in human diet. Using the next-generation sequencing, -Illumina HiSeq2500, ~ 30 million small RNA sequence reads were generated from C. papaya young leaves, resulting in the identification of a total of 1798 known and 49 novel miRNAs. Selected novel C. papaya miRNAs were predicted to regulate certain human targets, and subsequent annotation of gene functions indicated a probable role in various biological processes and pathways, such as MAPK, WNT, and GPCR signaling pathways, and platelet activation. These presumptive target gene in humans were predominantly linked to various diseases, including cancer, diabetes, mental illness, and platelet disorder. The computational finding of this study provides insights into how C. papaya-derived miRNAs may regulate certain conditions of human disease and provide a new perspective on human health. However, the therapeutic potential of C. papaya miRNA can be further explored through experimental studies.

Recent trends in miRNA therapeutics and the application of plant miRNA for prevention and treatment of human diseases

Background

Researchers now have a new avenue to investigate when it comes to miRNA-based therapeutics. miRNAs have the potential to be valuable biomarkers for disease detection. Variations in miRNA levels may be able to predict changes in normal physiological processes. At the epigenetic level, miRNA has been identified as a promising candidate for distinguishing and treating various diseases and defects.

Main body

In recent pharmacology, plants miRNA-based drugs have demonstrated a potential role in drug therapeutics. The purpose of this review paper is to discuss miRNA-based therapeutics, the role of miRNA in pharmacoepigenetics modulations, plant miRNA inter-kingdom regulation, and the therapeutic value and application of plant miRNA for cross-kingdom approaches. Target prediction and complementarity with host genes, as well as cross-kingdom gene interactions with plant miRNAs, are also revealed by bioinformatics research. We also show how plant miRNA can be transmitted from one species to another by crossing kingdom boundaries in this review. Despite several unidentified barriers to plant miRNA cross-transfer, plant miRNA-based gene regulation in trans-kingdom gene regulation may soon be valued as a possible approach in plant-based drug therapeutics.

Conclusion

This review summarised the biochemical synthesis of miRNAs, pharmacoepigenetics, drug therapeutics and miRNA transkingdom transfer.

Beneficial Effects of Bovine Milk Exosomes in Metabolic Interorgan Cross-Talk

Extracellular vesicles are membrane-enclosed secreted vesicles involved in cell-to-cell communication processes, identified in virtually all body fluids. Among extracellular vesicles, exosomes have gained increasing attention in recent years as they have unique biological origins and deliver different cargos, such as nucleic acids, proteins, and lipids, which might mediate various health processes. In particular, milk-derived exosomes are proposed as bioactive compounds of breast milk, which have been reported to resist gastric digestion and reach systemic circulation, thus being bioavailable after oral intake. In the present manuscript, we critically discuss the available evidence on the health benefits attributed to milk exosomes, and we provide an outlook for the potential future uses of these compounds. The use of milk exosomes as bioactive ingredients represents a novel avenue to explore in the context of human nutrition, and they might exert important beneficial effects at multiple levels, including but not limited to intestinal health, bone and muscle metabolism, immunity, modulation of the microbiota, growth, and development.

The Anti-Inflammatory Effect of Cabbage Leaves Explained by the Influence of bol-miRNA172a on FAN Expression

Recently, the possibility of cross-kingdom gene expression regulation by miRNAs from other species (“xenomiRs”), specifically from plants, has acquired scientific meaning. Based on the one of oldest methods for dealing with inflammation via the use of cabbage leaf compresses, we investigated the effects of Brassica oleracea derived miR172a on the potential human target gene encoding FAN (Factor Associated with Neutral Sphingomyelinase Activation) protein. In vitro experiments showed a decrease in FAN protein levels in both human and mouse cells transfected with bol-miRNA172a. As the FAN protein mediates inflammatory responses, the potential of miR172a to mitigate the inflammatory process was tested in a mouse model of rheumatoid arthritis. Animal studies showed the decreased oedema of inflamed paws in mouse with rheumatoid arthritis model induced after treatment with miR172a.

A bovine miRNA, bta-miR-154c, withstands in vitro human digestion but does not affect cell viability of colorectal human cell lines after transfection

Colorectal cancer (CRC) is the third most frequent human cancer with over 1.3 million new cases globally. CRC is a complex disease caused by interactions between genetic and environmental factors; in particular, high consumption of red meat, including beef, is considered a risk factor for CRC initiation and progression. Recent data demonstrate that exogenous microRNAs (miRNAs) entering the body via ingestion could pose an effect on the consumer. In this study, we focused on bovine miRNAs that do not share a seed sequence with humans and mice. We identified bta-miR-154c, a bovine miRNA found in edible parts of beef and predicted via cross-species bioinformatic analysis to affect cancer-related pathways in human cells. When bovine tissue was subjected to cooking and a simulation of human digestion, bta-miR-154c was still detected after all procedures, albeit at reduced concentrations. However, lipofection of bta-miR-154c in three different colorectal human cell lines did not affect their viability as evaluated at various time points and concentrations. These data indicate that bta-miR-154c (a) may affect cancer-related pathways in human cells, (b) can withstand digestion and be detected after all stages of an in vitro digestion protocol, but (c) it does not appear to alter epithelial cell viability after entering human enterocytes, even at supraphysiological amounts. Further experiments will elucidate whether bta-miR-154c exerts a different functional effect on the human gut epithelium, which may cause it to contribute to CRC progression through its consumption.

Identification of Bovine miRNAs with the Potential to Affect Human Gene Expression

Milk and other products from large mammals have emerged during human evolution as an important source of nutrition. Recently, it has been recognized that exogenous miRNAs (mRNA inhibited RNA) contained in milk and other tissues of the mammalian body can enter the human body, which in turn have the ability to potentially regulate human metabolism by affecting gene expression. We studied for exogenous miRNAs from Bos taurus that are potentially contain miRNAs from milk and that could act postprandially as regulators of human gene expression. The interaction of 17,508 human genes with 1025 bta-miRNAs, including 245 raw milk miRNAs was studied. The milk bta-miR-151-5p, bta-miR-151-3p, bta-miRNA-320 each have 11 BSs (binding sites), and bta-miRNA-345-5p, bta-miRNA-614, bta-miRNA-1296b and bta-miRNA-149 has 12, 14, 15 and 26 BSs, respectively. The bta-miR-574-5p from cow’s milk had 209 human genes in mRNAs from one to 25 repeating BSs. We found 15 bta-miRNAs that have 100% complementarity to the mRNA of 13 human target genes. Another 12 miRNAs have BSs in the mRNA of 19 human genes with 98% complementarity. The bta-miR-11975, bta-miR-11976, and bta-miR-2885 BSs are located with the overlap of nucleotide sequences in the mRNA of human genes. Nucleotide sequences of BSs of these miRNAs in 5′UTR mRNA of human genes consisted of GCC repeats with a total length of 18 nucleotides (nt) in 18 genes, 21 nt in 11 genes, 24 nt in 14 genes, and 27–48 nt in nine genes. Nucleotide sequences of BSs of bta-miR-11975, bta-miR-11976, and bta-miR-2885 in CDS mRNA of human genes consisted of GCC repeats with a total length of 18 nt in 33 genes, 21 nt in 13 genes, 24 nt in nine genes, and 27–36 nt in 11 genes. These BSs encoded polyA or polyP peptides. In only one case, the polyR (SLC24A3 gene) was encoded. The possibility of regulating the expression of human genes by exogenous bovine miRNAs is discussed.

Biogenesis, Trafficking, and Function of Small RNAs in Plants

Small RNAs (sRNAs) encoded by plant genomes have received widespread attention because they can affect multiple biological processes. Different sRNAs that are synthesized in plant cells can move throughout the plants, transport to plant pathogens via extracellular vesicles (EVs), and transfer to mammals via food. Small RNAs function at the target sites through DNA methylation, RNA interference, and translational repression. In this article, we reviewed the systematic processes of sRNA biogenesis, trafficking, and the underlying mechanisms of its functions.

Dietary bovine milk miRNAs transported in extracellular vesicles are partially stable during GI digestion, are bioavailable and reach target tissues but need a minimum dose to impact on gene expression

PURPOSE

Extracellular RNAs are unstable and rapidly degraded unless protected. Bovine-milk extracellular vesicles (EVs) confer protection to dietary miRNAs, although it remains unclear whether this importantly improves their chances of reaching host target cells to exert biological effects.

METHODS

Caco-2, HT-29, Hep-G2 and FHs-74 cell lines were exposed to natural/labelled milk EVs to evaluate cellular uptake. Five frequently reported human milk miRNAs (miR-146b-5p, miR-148a-3p, miR-30a-5p, miR-26a-5p, and miR-22-3p) were loaded into EVs. The intracellular concentration of each miRNA in cells was determined. In addition, an animal study giving an oral dose of loaded EVs in C57BL6/ mice were performed. Gene expression regulation was assessed by microarray analysis.

RESULTS

Digestive stability analysis showed high overall degradation of exogenous miRNAs, although EV-protected miRNAs better resisted gastrointestinal digestion compared to free miRNAs (tenfold higher levels). Importantly, orally delivered EV-loaded miRNAs reached host organs, including brain, in mice. However, no biological effect has been identified.

CONCLUSION

Milk EVs protect miRNAs from degradation and facilitate cellular uptake. miRNA concentration in EVs from bovine milk might be insufficient to produce gene modulation. Nevertheless, sizable amounts of exogenous miRNAs may be loaded into EVs, and orally delivered EV-loaded miRNAs can reach tissues in vivo, increasing the possibility of exerting biological effects. Further investigation is justified as this could have an impact in the field of nutrition and health (i.e., infant formulas elaboration).

Influence of the Bioactive Diet Components on the Gene Expression Regulation

Diet bioactive components, in the concept of nutrigenetics and nutrigenomics, consist of food constituents, which can transfer information from the external environment and influence gene expression in the cell and thus the function of the whole organism. It is crucial to regard food not only as the source of energy and basic nutriments, crucial for living and organism development, but also as the factor influencing health/disease, biochemical mechanisms, and activation of biochemical pathways. Bioactive components of the diet regulate gene expression through changes in the chromatin structure (including DNA methylation and histone modification), non-coding RNA, activation of transcription factors by signalling cascades, or direct ligand binding to the nuclear receptors. Analysis of interactions between diet components and human genome structure and gene activity is a modern approach that will help to better understand these relations and will allow designing dietary guidances, which can help maintain good health.

Cross-kingdom regulation by dietary plant miRNAs: an evidence-based review with recent updates

As non-coding RNA molecules, microRNAs (miRNAs) are widely known for their critical role in gene regulation. Recent studies have shown that plant miRNAs obtained through dietary oral administration can survive in the gastrointestinal (GI) tract, enter the circulatory system and regulate endogenous mRNAs. Diet-derived plant miRNAs have 2'-O-methylated modified 3'ends and high cytosine and guanine (GC) content, as well as exosomal packaging, which gives them high stability even in the harsh environment of the digestive system and circulatory system. The latest evidence shows that dietary plant miRNAs can not only be absorbed in the intestine, but also be absorbed and packaged by gastric epithelial cells and then secreted into the circulatory system. Alternatively, these biologically active plant-derived miRNAs may also affect the health of the host by affecting the function of the microbiome, while not need to be taken into the host's circulatory system and transferred to remote tissues. This cross-kingdom regulation of miRNAs gives us hope for exploring their therapeutic potential and as dietary supplements. However, doubts have also been raised about the cross-border regulation of miRNAs, suggesting that technical flaws in the experiments may have led to this hypothesis. In this article, we summarize the visibility of dietary plant miRNAs in the development of human health and recent research data on their use in therapeutics. The regulation of plant miRNAs across kingdoms is a novel concept. Continued efforts in this area will broaden our understanding of the biological role of plant miRNAs and will open the way for the development of new approaches to prevent or treat human diseases.

Lab-to-Field Transition of RNA Spray Applications - How Far Are We?

The drastic loss of biodiversity has alarmed the public and raised sociopolitical demand for chemical pesticide-free plant production, which is now treated by governments worldwide as a top priority. Given this global challenge, RNAi-based technologies are rapidly evolving as a promising substitute to conventional chemical pesticides. Primarily, genetically modified (GM) crops expressing double-stranded (ds)RNA-mediating gene silencing of foreign transcripts have been developed. However, since the cultivation of GM RNAi crops is viewed negatively in numerous countries, GM-free exogenous RNA spray applications attract tremendous scientific and political interest. The sudden rise in demand for pesticide alternatives has boosted research on sprayable RNA biopesticides, generating significant technological developments and advancing the potential for field applications in the near future. Here we review the latest advances that could pave the way for a quick lab-to-field transition for RNA sprays, which, as safe, selective, broadly applicable, and cost-effective biopesticides, represent an innovation in sustainable crop production. Given these latest advances, we further discuss technological limitations, knowledge gaps in the research, safety concerns and regulatory requirements that need to be considered and addressed before RNA sprays can become a reliable and realistic agricultural approach.

Where Epigenetics Meets Food Intake: Their Interaction in the Development/Severity of Gout and Therapeutic Perspectives

Gout is the most frequent form of inflammatory arthritis in the world. Its prevalence is particularly elevated in specific geographical areas such as in the Oceania/Pacific region and is rising in the US, Europe, and Asia. Gout is a severe and painful disease, in which co-morbidities are responsible for a significant reduction in life expectancy. However, gout patients remain ostracized because the disease is still considered "self-inflicted", as a result of unhealthy lifestyle and excessive food and alcohol intake. While the etiology of gout flares is clearly associated with the presence of monosodium urate (MSU) crystal deposits, several major questions remain unanswered, such as the relationships between diet, hyperuricemia and gout flares or the mechanisms by which urate induces inflammation. Recent advances have identified gene variants associated with gout incidence. Nevertheless, genetic origins of gout combined to diet-related possible uric acid overproduction account for the symptoms in only a minor portion of patients. Hence, additional factors must be at play. Here, we review the impact of epigenetic mechanisms in which nutrients (such as ω-3 polyunsaturated fatty acids) and/or dietary-derived metabolites (like urate) trigger anti/pro-inflammatory responses that may participate in gout pathogenesis and severity. We propose that simple dietary regimens may be beneficial to complement therapeutic management or contribute to the prevention of flares in gout patients.

MicroRNA: A mediator of diet-induced cardiovascular protection

Diets containing nutrients such as polyunsaturated fatty acids, polyphenols, or vitamins have been shown to have cardiovascular benefits. Micro (mi)RNAs are fundamental regulators of gene expression and function in the cardiovascular system. Diet-induced cardiovascular benefits are associated with changes in endogenous expression of miRNAs in the cardiovascular system. In addition, emerging studies have shown that miRNAs present in the food can be transported in the circulation to tissues. These exogenous miRNAs may also affect cardiovascular function contributing to the diet-induced benefits. This review discusses the emerging role of both endogenous and exogenous miRNAs as mediators of diet-induced cardiovascular protection. Understanding the mechanisms of diet-mediated actions through modulation of miRNA may provide a potential strategy for new therapies.

EV Cargo Sorting in Therapeutic Development for Cardiovascular Disease

Cardiovascular disease remains the leading cause of morbidity and mortality in the world. Thus, therapeutic interventions to circumvent this growing burden are of utmost importance. Extracellular vesicles (EVs) actively secreted by most living cells, play a key role in paracrine and endocrine intercellular communication via exchange of biological molecules. As the content of secreted EVs reflect the physiology and pathology of the cell of their origin, EVs play a significant role in cellular homeostasis, disease pathogenesis and diagnostics. Moreover, EVs are gaining popularity in clinics as therapeutic and drug delivery vehicles, transferring bioactive molecules such as proteins, genes, miRNAs and other therapeutic agents to target cells to treat diseases and deter disease progression. Despite our limited but growing knowledge of EV biology, it is imperative to understand the complex mechanisms of EV cargo sorting in pursuit of designing next generation EV-based therapeutic delivery systems. In this review, we highlight the mechanisms of EV cargo sorting and methods of EV bioengineering and discuss engineered EVs as a potential therapeutic delivery system to treat cardiovascular disease.

Plant-derived xenomiRs and cancer: Cross-kingdom gene regulation

Exosomal microRNAs (miRNAs) critically regulate several major intracellular and metabolic activities, including cancer evolution. Currently, increasing evidence indicates that exosome harbor and transport these miRNAs from donor cells to neighboring and distantly related recipient cells, often in a cross-species manner. Several studies have reported that plant-based miRNAs can be absorbed into the serum of humans, where they hinder the expression of human disease-related genes. Moreover, few recent studies have demonstrated the role of these xenomiRs in cancer development and progression. However, the cross-kingdom gene regulation hypothesis remains highly debatable, and many follow up studies fail to reproduce the same. There are reports that show no effect of plant-derived miRNAs on mammalian cancers. The foremost cause of this controversy remains the lack of reproducibility of the results. Here, we reassess the latest developments in the field of cross-kingdom transference of miRNAs, emphasizing on the role of the diet-based xenomiRs on cancer progression.