Unser 10. Leibniz Plant Biochemistry Symposium am 7. und 8. Mai war ein großer Erfolg. Thematisch ging es in diesem Jahr um neue Methoden und Forschungsansätze der Naturstoffchemie. Die exzellenten Vorträge über Wirkstoffe…
Omanische Heilpflanze im Fokus der Phytochemie IPB-Wissenschaftler und Partner aus Dhofar haben jüngst die omanische Heilpflanze Terminalia dhofarica unter die phytochemische Lupe genommen. Die Pflanze ist reich an…
Geschmack ist vorhersagbar: Mit FlavorMiner. FlavorMiner heißt das Tool, das IPB-Chemiker und Partner aus Kolumbien jüngst entwickelt haben. Das Programm kann, basierend auf maschinellem Lernen (KI), anhand der…
Hornstedtia scyphifera (J.Koenig) Steud. represents a lesser-known member of the ginger family (Zingiberaceae) that is used in Malaysia as spice and traditional medicine. The phytochemical investigation of leaves from this species utilizing diverse analytical methods has provided comprehensive insights into its chemical profile for the first time. Headspace gas chromatography-mass spectrometry (HS-GCMS) and GCMS analyses of essential oil and nonpolar extracts verified α-pinene, camphene, p-cymene, and camphor as main volatile compounds. Metabolite profiling of the crude extract by ultra-high-performance-liquid chromatography-high resolution mass spectrometry (UHPLC-HRMS) unveiled terpenoids, flavonoids and other phenolics as major compound classes. Isolation and follow-up structure elucidation, involving 1D and 2D NMR, HRMS, UV and CD analysis, yielded two new sesquiterpenoids, (1R,5S,6S,7R,10R)-mustak-14-oic acid (1) and (1R,6S,7S,10R)-6-hydroxy-anhuienosol (2), along with 24 known compounds (seven terpenoids, seven flavonoids, ten phenolics), 21 of these never reported for H. scyphifera. Additionally, the crude extract and fractions from the purification process were screened for antibacterial and antifungal activity. This is supplemented by an extensive literature research for described bioactivities of all isolated compounds. Our results support and explain previously detected antimicrobial, antifungal and neuroprotective effects of H. scyphifera extracts and provide evidence for its potential pharmacological importance.
Preprints
Arndt, H.; Bachurski, M.; Yuanxiang, P.; Franke, K.; Wessjohann, L. A.; Kreutz, M. R.; Grochowska, K. M.;A screen of plant-based natural products revealed that quercetin prevents amyloid-β uptake in astrocytes as well as resulting astrogliosis and synaptic dysfunctionResearch Square(2024)DOI: 10.21203/rs.3.rs-4155455/v1
Two connected histopathological hallmarks of Alzheimer’s disease (AD) are chronic neuroinflammation and synaptic dysfunction. The accumulation of the most prevalent posttranslationally modified form of Aβ1–42, pyroglutamylated amyloid-β (Aβ3(pE)-42) in astrocytes is directly linked to glial activation and the release of proinflammatory cytokines that in turn contribute to early synaptic dysfunction in AD. At present the mechanisms of Aβ3(pE)-42 uptake to astrocytes are unknown and pharmacological interventions that interfere with this process are not available. Here we developed a simple screening assay to identify substances from a plant extract library that prevent astroglial Aβ3(pE)-42 uptake. We first show that this approach yields valid and reproducible results. Second, we show endocytosis of Aβ3(pE)-42 oligomers by astrocytes and that quercetin, a plant flavonol, is effective to specifically block astrocytic buildup of oligomeric Aβ3(pE)-42. Importantly, quercetin does not induce a general impairment of endocytosis. However, it efficiently protects against early synaptic dysfunction following exogenous Aβ3(pE)-42 application.
Publikationen in Druck
Arndt, H.; Bachurski, M.; Yuanxiang, P.; Franke, K.; Wessjohann, L. A.; Kreutz, M. R.; Grochowska, K. M.;A screen of plant-based natural products revealed that quercetin prevents pyroglutamylated amyloid-β (Aβ3(pE)-42) uptake in astrocytes as well as resulting astrogliosis and synaptic dysfunctionMol. Neurobiol.(2024)DOI: 10.1007/s12035-024-04509-6
Two connected histopathological hallmarks of Alzheimer’s disease (AD) are chronic neuroinflammation and synaptic dysfunction. The accumulation of the most prevalent posttranslationally modified form of Aβ1–42, pyroglutamylated amyloid-β (Aβ3(pE)-42) in astrocytes is directly linked to glial activation and the release of proinflammatory cytokines that in turn contribute to early synaptic dysfunction in AD. At present, the mechanisms of Aβ3(pE)-42 uptake to astrocytes are unknown and pharmacological interventions that interfere with this process are not available. Here we developed a simple screening assay to identify substances from a plant extract library that prevent astroglial Aβ3(pE)-42 uptake. We first show that this approach yields valid and reproducible results. Second, we show endocytosis of Aβ3(pE)-42 oligomers by astrocytes and that quercetin, a plant flavonol, is effective to specifically block astrocytic buildup of oligomeric Aβ3(pE)-42. Importantly, quercetin does not induce a general impairment of endocytosis. However, it efficiently protects against early synaptic dysfunction following exogenous Aβ3(pE)-42 application.
Publikation
Nagia, M.; Morgan, I.; Gamel, M. A.; Farag, M. A.;Maximizing the value of indole-3-carbinol, from its distribution in dietary sources, health effects, metabolism, extraction, and analysis in food and biofluidsCrit. Rev. Food Sci. Nutr.648133-8154(2024)DOI: 10.1080/10408398.2023.2197065
Indole-3-carbinol (I3C) is a major dietary component produced in Brassica vegetables from glucosinolates (GLS) upon herbivores’ attack. The compound is gaining increasing interest due to its anticancer activity. However, reports about improving its level in plants or other sources are still rare. Unfortunately, I3C is unstable in acidic media and tends to polymerize rendering its extraction and detection challenging. This review presents a multifaceted overview of I3C regarding its natural occurrence, biosynthesis, isolation, and extraction procedure from dietary sources, and optimization for the best recovery yield. Further, an overview is presented on its metabolism and biotransformation inside the body to account for its health benefits and factors to ensure the best metabolic yield. Compile of the different analytical approaches for I3C analysis in dietary sources is presented for the first time, together with approaches for its detection and its metabolism in body fluids for proof of efficacy. Lastly, the chemopreventive effects of I3C and the underlying action mechanisms are summarized. Optimizing the yield and methods for the detection of I3C will assist for its incorporation as a nutraceutical or adjuvant in cancer treatment programs. Highlighting the complete biosynthetic pathway and factors involved in I3C production will aid for its future biotechnological production.