Small RNAs in eucaryotes: new clues for amplifying microRNA benefits

Abstract

miRNAs, the smallest nucleotide molecules able to regulate gene expression at post transcriptional level, are found in both animals and plants being involved in fundamental processes for growth and development of living organisms. The number of miRNAs has been hypothesized to increase when some organisms specialized the process of mastication and grinding of food. Further to the vertical transmission, miRNAs can undergo horizontal transmission among different species, in particular between plants and animals. In the last years, an increasing number of studies reported that miRNA passage occurs through feeding, and that in animals, plant miRNAs can survive the gastro intestinal digestion and transferred by blood into host cells, where they can exert their functions modulating gene expression. The present review reports studies on miRNAs during evolution, with particular focus on biogenesis and mechanisms regulating their stability in plants and animals. The different biogenesis and post biogenesis modifications allow to discriminate miRNAs of plant origin from those of animal origin, and make it possible to better clarify the controversial question on whether a possible cross-kingdom miRNA transfer through food does exist. The majority of human medicines and supplements derive from plants and a regular consumption of plant food is suggested for their beneficial effects in the prevention of metabolic diseases, cancers, and dietary related disorders. So far, these beneficial effects have been generally attributed to the content of secondary metabolites, whereas mechanisms regarding other components remain unclear. Therefore, in light of the above reported studies miRNAs could result another component for the medical properties of plants. miRNAs have been mainly studied in mammals characterizing their sequences and molecular targets as available in public databases. The herein presented studies provide evidences that miRNA situation is much more complex than the static situation reported in databases. Indeed, miRNAs may have redundant activities, variable sequences, different methods of biogenesis, and may be differently influenced by external and environmental factors. In-depth knowledge of mechanisms of synthesis, regulation and transfer of plant miRNAs to other species can open new frontiers in the therapy of many human diseases, including cancer.

Positive association between COVID-19 deaths and influenza vaccination rates in elderly people worldwide

“…The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is an ongoing global health crisis (Yuen et al, 2020), directly and indirectly impacting all spheres of human life (Ozili & Arun, 2020).…”

RNA-sequencing reveals the expression profiles of tsRNAs and their potential carcinogenic role in cholangiocarcinoma

“…Noncoding RNAs(ncRNAs) are consisted of microRNAs (miRNAs), long ncRNAs (lncRNAs), circular RNAs (circRNAs), and tsRNAs, which are small RNAs that are not capable of encoding proteins (9,21,22). Recently, with the application of high-throughput sequencing technology and biological information analyses in ncRNAs, researchers have revealed many new research theories, mainly including the theory that ncRNAs such as tsRNA (including tRFs and tiRNAs) are of great importance in the initiation and development of tumors and can be used as molecular markers for tumor diagnosis or molecular targets for treatment.…”

Epigenetics of Aging and Aging-Associated Diseases

“…Mechanistically, an imbalance between histone modifications of osteogenic and adipogenic genes was proposed as an underlying mechanism of the development of musculoskeletal diseases. For instance, HDAC3 promotes osteogenesis and inhibits lipogenesis, while EZH2 and HDAC6 show opposite effects [ 165 , 171 ]. In bone marrow aspirates from human adults, it was demonstrated via retroviral-mediated enforced Ezh2 expression in MSCs that the differentiation potential into adipocytes was higher compared to vector control cells, along with reduced Runx2 transcription.…”

“…Subsequent siRNA-mediated EZH2 depletion led to enhanced RUNX2 expression. Using ChIP-qPCR, the authors demonstrated that enforced EZH2 expression in MSCs resulted in increased H3K27me3 on transcriptional start sites of RUNX2 , leading to a suppression of osteogenesis and marking EZH2 as positive regulator of adipogenesis and negative regulator of osteogenesis [ 171 , 172 , 173 , 174 , 175 ]. In another study, age-related bone loss was found linked to an increase in EZH2.…”