University of Shizuoka

An international team has found a family of natural compounds with potential as new and more effective treatments for parasitic worms. The compounds stall the unique metabolic process that worms use to survive in the human gut. An international team led by researchers at the University of Toronto has found a family of natural compounds with potential as new and more effective treatments for parasitic worms. The compounds stall the unique metabolic process that worms use to survive in the human gut. Parasitic worms transmitted through soil wreak havoc in developing countries in the tropics. Infection by these parasites leads to malaise, weakness, malnutrition and other debilitating symptoms, and can cause developmental defects in children and impair their growth. "Soil-transmitted parasitic worms infect over one billion people around the world, typically in low-income communities of developing countries without comprehensive health care and infrastructure for sanitation," said Taylor Davie, first author on the study and PhD student at U of T's Donnelly Centre for Cellular and Biomolecular Research. "Parasites are becoming less susceptible to the few anthelmintic drugs available, so there's an urgent need to find new compounds." The study was published today in the journal Nature Communications. Many parasitic worm species live out a large portion of their life cycle inside a human host. To adapt to the environmental conditions of the gut, particularly a lack of oxygen, the parasite switches to a type of metabolism that depends on a molecule called rhodoquinone (RQ). The parasite can survive inside its human host for many months using RQ-dependent metabolism. The research team chose to target the adaptive metabolic process of the parasitic worm because RQ is only present in the parasite's system -- humans do not produce or use RQ. Therefore, compounds that can regulate the molecule's production or activity would selectively kill the parasite, with no harm done to the human host. The researchers conducted a screen of natural compounds isolated from plants, fungi and bacteria on the model organism C. elegans. While it is not a parasite, this worm also depends on RQ for metabolism when oxygen is not available. "This is the first time that we have been able to screen for drugs that specifically target the unusual metabolism of these parasites," said Andrew Fraser, principal investigator on the study and professor of molecular genetics at the Donnelly Centre and the Temerty Faculty of Medicine. "The screen was only possible because of recent progress made by our group and others in using C. elegans to study RQ-dependent metabolism, and our collaboration with RIKEN, one of Japan's biggest research agencies. We screened their world-class collection of 25,000 natural compounds, resulting in our discovery of a family of benzimidazole compounds that kills worms relying on this type of metabolism." The researchers suggest a multi-dose regimen using the newly discovered family of compounds to treat parasitic worms. While a single-dose treatment is easier to facilitate in mass drug administration programs, a longer treatment program would eliminate the parasite more effectively. "We are very pleased with the results of the study, which made use of our library," said Hiroyuki Osada, professor of pharmacy at the University of Shizuoka and group director of the Chemical Biology Research Group at the RIKEN Center for Sustainable Resource Science. "The study shows the power of the screening approach, allowing researchers in this case to search through a very large number of molecules within a focused collection of natural products. Screens are very efficient, which is key for addressing urgent research questions of global relevance like this one." Next steps for the research team are to refine the new class of inhibitors through additional in vivo testing with parasitic worms, which will be performed by the Keiser lab at the University of Basel in Switzerland, and to continue screening for compounds that inhibit RQ. "This study is just the beginning," said Fraser. "We have found several other very powerful compounds that affect this metabolism, including, for the first time, a compound that blocks the ability of the worms to make RQ. We hope our screens will deliver drugs to treat major pathogens around the world." This research was supported by the Canadian Institutes of Health Research and the European Molecular Biology Organization.

Generating specific cell lineages from induced pluripotent stem cells and embryonic stem cells is the holy grail of regenerative medicine. Guiding iPSCs toward a target cell line has garnered much attention, but the process remains challenging. Now, researchers from Japan have discovered that an anti-nucleolin DNA aptamer, iSN04, can determine a cell’s lineage during differentiation. By demonstrating the generation of cardiomyocytes from murine pluripotent stem cells, their concept shows promise as a regenerative therapy. Generating specific cell lineages from induced pluripotent stem cells and embryonic stem cells is the holy grail of regenerative medicine. Guiding iPSCs toward a target cell line has garnered much attention, but the process remains challenging. Now, researchers from Japan have discovered that an anti-nucleolin DNA aptamer, iSN04, can determine a cell's lineage during differentiation. By demonstrating the generation of cardiomyocytes from murine pluripotent stem cells, their concept shows promise as a regenerative therapy. Self-renewal and pluripotency-the capacity to form any cell lineage-are inherent characteristics of induced pluripotent stem cells (iPSCs). Furthermore, they are highly prized in regenerative therapies targeting cardiovascular, neurological, and metabolic diseases as they are immunologically suitable for transplantation back into a donor. Unfortunately, regenerative medicine is not yet feasible outside a laboratory setting as available protocols to generate target cells are complicated and expensive. This raises a pertinent question: Can regulating the fate of stem cells in clinical settings and at scale be made more economical? A team of researchers from Shinshu University, the National Institute of Advanced Industrial Science and Technology, and the University of Shizuoka in Japan set out to address this question by leveraging nucleic acid aptamers. Aptamers are single-stranded pieces of DNA that bind to target proteins and are able to modulate signaling cascades during cell differentiation when a stem cell commits to a specific functional role or phenotype. They hold promise in regenerative medicine as they are easily modified, can be synthesized economically, and are suitable for long-term storage. The team, led by Associate Professor Tomohide Takaya from the Department of Agricultural and Life Sciences at Shinshu University, recently discovered that an anti-nucleolin aptamer, myogenetic oligodeoxynucleotide iSN04, induced myocardial differentiation in embryonic stem cells (ESCs). The study was led by Mina Ishioka, a graduate student in Dr. Takaya's laboratory, and published in The International Journal of Molecular Sciences on 21 September 2023. "We had previously found that iSN04 promoted myogenic precursor cells (myoblasts) to differentiate into skeletal muscle cells and had hypothesized that the aptamer also enhanced differentiation of pluripotent stem cells. We were intrigued by the prospect of using iSN04 to promote iPSC differentiation into cardiomyocytes as this could lead to regenerating heart tissue," says Dr. Takaya, elaborating on the team's motivation to pursue the research. Using various assays like RNA sequencing, cell staining and imaging, and molecular interaction and pathway analysis, the researchers investigated iSN04's effect on murine ESCs and iPSCs. iSN04 treatment under differentiating conditions inhibited stem cell commitment to the cardiac lineage. However, when these pluripotent stem cells were treated after experiencing differentiating conditions for five days, specific marker genes were upregulated, and the cells committed to forming beating cardiomyocytes. "Ours is the first report to confirm a DNA aptamer that allows cardiomyocytes to develop from iPSCs," explains Dr. Takaya when asked about the significance of the work. "We uncovered two mechanisms of nucleolin interference with iSN04 at play whereby early treatment inhibits cardiomyogenesis, while treatment at a later stage enhances the generation of cardiac progenitors. First, iSN04 governs the translocation of nucleolin protein between the cytoplasm, plasma membrane, and nucleus. Second, it results in the modulation of the Wnt signaling pathway that governs cell differentiation." The immunostaining experiments revealed that nucleolin was retained in the nucleoli following iSN04 treatment. Nucleolar nucleolin has a role in chromatin remodeling and gene transcription, and interestingly enough, Wnt pathway genes were differentially expressed in the RNA-seq data following iSN04 suppression. The team postulates that the iSN04-anchored nucleolin alters gene expression and Wnt signaling. Ultimately, terminal cell differentiation commits to the cardiomyocyte lineage. And how could these findings impact regenerative medicine and patients' lives in the long term? Dr. Takaya provides insights into the broader implications of their work. "We believe there is a strong case to be made for further studies evaluating DNA aptamers in regenerative medicine. Aptamers are cost-effective and open up the possibility of producing specific cells from the patient's stem cells. But it doesn't end there! Since the aptamers can regulate stem cell fate, they can serve as therapeutic agents for many conditions linked to stem cell dysfunction," he concludes.

TOKYO, Feb. 22, 2023 /PRNewswire/ -- Ajinomoto Bio-Pharma Services ("Aji Bio-Pharma"), a leading provider of biopharmaceutical contract development and manufacturing services, is pleased to announce the development of a new enzyme for double strand oligonucleotide formation with high productivity. In collaboration with researchers from the University of Shizuoka, Aji Bio-Pharma succeeded in developing a highly functional artificial RNA ligase using the ancestral design method. It was found that this artificial RNA ligase has higher thermostability than natural RNA ligase as well as superior ligation activity for RNA fragments containing xenonucleic acid. When using the natural RNA ligase for RNA fragments (including xenonucleic acid) as reaction substrates to synthesize a marketed siRNA drug substance, the yield was only 20% after 24 hours of reaction. In contrast, when using the highly functional artificial RNA ligase, the reaction yield improved to 80% under the same conditions, confirming that it has properties suitable for enzymatic synthesis of nucleic acid medicines. This approach attains more productive and environmentally safe oligonucleotide synthesis when compared to the conventional method. "We are excited to provide new research to our partners and support them in their efforts to supply lifesaving therapeutics," said Yusuke Hagiwara, Senior Researcher, Ajinomoto Bioscience & Fine Chemicals Research Laboratories. "This discovery for siRNA is a great example of Aji Bio-Pharma continuing to provide reliable and innovative solutions to our clients." The RNA fragments used as reaction substrates can be produced by not only conventional solid phase synthesis, but also by Ajinomoto Co.'s AJIPHASE® technology, especially in large quantities and with high purity. This achievement is expected to be applied as one of the technologies that enables the mass production of nucleic acid drugs with high efficiency and high purity. This result was presented in the journal "Applied and Environmental Microbiology" published by the American Society for Microbiology. About Ajinomoto Co. and Ajinomoto Bio-Pharma Services Based on the corporate message "Eat Well, Live Well.", Ajinomoto Co., Inc. has been scientifically pursuing the possibilities of amino acids to aim for future growth by creating new value through sustainable and innovative solutions for communities and society. For additional information about Ajinomoto Co. (TYO: 2802), please visit . As its pharmaceutical arm, Ajinomoto Bio-Pharma Services is a fully integrated contract development and manufacturing organization (CDMO) with sites in Belgium, United States, Japan, and India, providing comprehensive development, cGMP manufacturing, and aseptic fill finish services for small through large molecule APIs and intermediates. For more information about Ajinomoto Bio-Pharma Services, please visit . In addition, Ajinomoto Co. and Ajinomoto Bio-Pharma Services offer a broad range of innovative platform technologies and capabilities for pre-clinical and pilot programs to commercial quantities, including AJIPHASE® oligonucleotide manufacturing technology, CORYNEX® and TALAMAX® protein expression systems, AJICAP® site-specific conjugation and linker technologies for ADCs, and continuous flow manufacturing. For additional information on the platform technologies, please visit . Company Codes: Tokyo:2802, OTC-PINK:AJINY