Leucocontextins A-R, lanostane-type triterpenoids from Ganoderma leucocontextum

Recent progress on triterpenoid derivatives and their anticancer potential

Cancer poses a significant global public health challenge, with commonly used adjuvant or neoadjuvant chemotherapy often leading to adverse side effects and drug resistance. Therefore, advancing cancer treatment necessitates the ongoing development of novel anticancer agents with diverse structures and mechanisms of action. Natural products remain crucial in the process of drug discovery, serving as a primary source for pharmaceutical leads and therapeutic advancements. Triterpenoids are particularly compelling due to their complex structures and wide array of biological activities. Recent research has demonstrated that naturally occurring triterpenes and their derivatives have the potential to serve as promising candidates for new drug development. This review aims to comprehensively explore the anticancer properties of triterpenoids and their synthetic analogs, with a focus on recent advancements. Various aspects, such as synthesis, phytochemistry, and molecular simulation for structure-activity relationship analyses, are summarized. It is anticipated that triterpenoid derivatives will emerge as notable anticancer agents following further investigation into their mechanisms of action and in vivo studies.

Telomere-to-Telomere Genome Assembly of Tibetan Medicinal Mushroom Ganoderma leucocontextum and the First Copia Centromeric Retrotransposon in Macro-Fungi Genome

A complete telomere-to-telomere (T2T) genome has been a longstanding goal in the field of genomic research. By integrating high-coverage and precise long-read sequencing data using multiple assembly strategies, we present here the first T2T gap-free genome assembly of Ganoderma leucocontextum strain GL72, a Tibetan medicinal mushroom. The T2T genome, with a size of 46.69 Mb, consists 13 complete nuclear chromosomes and typical telomeric repeats (CCCTAA)n were detected at both ends of 13 chromosomes. The high mapping rate, uniform genome coverage, a complete BUSCOs of 99.7%, and base accuracy exceeding 99.999% indicate that this assembly represents the highest level of completeness and quality. Regions characterized by distinct structural attributes, including highest Hi-C interaction intensity, high repeat content, decreased gene density, low GC content, and minimal or no transcription levels across all chromosomes may represent potential centromeres. Sequence analysis revealed the first Copia centromeric retrotransposon in macro-fungi genome. Phylogenomic analysis identified that G. leucocontextum and G. tsugae diverged from the other Ganoderma species approximately 9.8-17.9 MYA. The prediction of secondary metabolic clusters confirmed the capability of this fungus to produce a substantial quantity of metabolites. This T2T gap-free genome will contribute to the genomic 'dark matter' elucidation and server as a great reference for genetics, genomics, and evolutionary studies of G. leucocontextum.

Evaluation of the acute toxicity and 28-days subacute toxicity of the alcoholic extract from Ganoderma leucocontextum

Ganoderma leucocontextum is a well-known traditional medicine in Tibet Autonomous Region, which has benefits, such as anti-hypoxia, neurotrophic action on nerves, easing coughs and relieving asthma, strengthening the body and prolonging life. However, few research have focused on its negative effects, possibly jeopardizing its safety. The purpose of this study is to evaluate the acute and subacute toxicity of an alcoholic extract from G. leucocontextum (GLA) in vivo. The phytochemical characterization analysis showed that alcoholic extract from G. leucocontextum were rich in polysaccharides, triterpenoids. Then, in acute oral toxicity, male and female mice from Institute of Cancer Research (ICR) were orally administered with 16 g/kg GLA and were observed for 14 days. In the subacute toxicity, male and female Sprague-Dawley (SD) rats were orally administered with 2, 4, and 8 g/kg doses of GLA for 28 days. There was no death or clinical changes in male and female mice in the acute toxicity test. During the subacute toxicity test, the difference in body weights, food consumption, biochemical and hematological parameters, and organ coefficients between treated and control groups were unrelated to GLA treatment. The obtained data show that the GLA had no significant toxic effects when administered orally to male and female rats in acute and subacute toxicity.

A Review of Ganoderma Triterpenoids and Their Bioactivities

For centuries, Ganoderma has been used as a traditional medicine in Asian countries to prevent and treat various diseases. Numerous publications are stating that Ganoderma species have a variety of beneficial medicinal properties, and investigations on different metabolic regulations of Ganoderma species, extracts or isolated compounds have been performed both in vitro and in vivo. However, it has frequently been questioned whether Ganoderma is simply a dietary supplement for health or just a useful "medication" for restorative purposes. More than 600 chemical compounds including alkaloids, meroterpenoids, nucleobases, nucleosides, polysaccharides, proteins, steroids and triterpenes were extracted and identified from Ganoderma, with triterpenes serving as the primary components. In recent years, Ganoderma triterpenes and other small molecular constituents have aroused the interest of chemists and pharmacologists. Meanwhile, considering the significance of the triterpene constituents in the development of new drugs, this review describes 495 compounds from 25 Ganoderma species published between 1984 and 2022, commenting on their source, biosynthetic pathway, identification, biological activities and biosynthesis, together with applications of advanced analytical techniques to the characterization of Ganoderma triterpenoids.

Whole-genome assembly of Ganoderma leucocontextum (Ganodermataceae, Fungi) discovered from the Tibetan Plateau of China

Ganoderma leucocontextum, a newly discovered species of Ganodermataceae in China, has diverse pharmacological activities. G. leucocontextum was widely cultivated in southwest China, but the systematic genetic study has been impeded by the lack of a reference genome. Herein, we present the first whole-genome assembly of G. leucocontextum based on the Illumina and Nanopore platform from high-quality DNA extracted from a monokaryon strain (DH-8). The generated genome was 50.05 Mb in size with a N50 scaffold size of 3.06 Mb, 78,206 coding sequences and 13,390 putative genes. Genome completeness was assessed using the Benchmarking Universal Single-Copy Orthologs (BUSCO) tool, which identified 96.55% of the 280 Fungi BUSCO genes. Furthermore, differences in functional genes of secondary metabolites (terpenoids) were analyzed between G. leucocontextum and G. lucidum. G. leucocontextum has more genes related to terpenoids synthesis compared to G. lucidum, which may be one of the reasons why they exhibit different biological activities. This is the first genome assembly and annotation for G. leucocontextum, which would enrich the toolbox for biological and genetic studies in G. leucocontextum.

Ganoderiol F purified from Ganoderma leucocontextum retards cell cycle progression by inhibiting CDK4/CDK6

This study was designed to purify molecules possess anti-cancer cell activity from the fruit body of Ganoderma leucocontextum. Bio-activity-guided purification and chromatographic separation of Ganoderma leucocontextum extract led to the enrichment of bioactive fractions and isolation of a single compound. The purified compound was identified as Ganoderiol F, which induced cancer cell death. In the in vivo experiments, we founded ethanol extract and ethyl acetate fraction inhibited tumor growth in the mice injected with 4T1 cells. We found that Ganoderiol F-mediated suppression of breast cancer cell viability occurred through cell cycle arrest. Ganoderiol F down-regulated expression of cyclin D, CDK4, CDK6, cyclin E and CDK2 and inhibited cell cycle progression arresting the cells in G1 phase. In addition, Ganoderiol F up-regulated pro-apoptotic Foxo3, down-regulated anti-apoptotic c-Myc, Bcl-2 and Bcl-w leading to apoptosis in human breast cancer cells MDA-MB-231. These results showed that c-Myc, cyclin D-CDK4/CDK6 and cyclin E-CDK2 are the central components of Ganoderiol F regulation of cell cycle progression. Hence Ganoderiol F may serve as a potential CDK4/CDK6 inhibitor for breast cancer therapy. Abbreviations: GLE: Ganoderma leucocontextum ethanol extract; GLEA: Ganoderma leucocontextum ethyl acetate fraction; GLPE: Ganoderma leucocontextum petroleum ether fraction; RP-HPLC: reversed-phase high-performance liquid chromatograph; DMEM: Dulbecco's modified Eagle's medium; FBS: fetal bovine serum; PAGE: polyacrylamide gel electrophoresis.

Eight new triterpenoids with inhibitory activity against HMG-CoA reductase from the medical mushroom Ganoderma leucocontextum collected in Tibetan plateau

Eight new triterpenoids, ganoleucoins T-Z(1-3, 5-8), and AA (9), together with eleven known triterpenes were isolated and identified from the wild fruiting bodies of the medicinal mushroom Ganoderma leucocontextum. The structures of new compounds were determined on the basis of NMR and MS spectral analysis. The inhibitory effects of 1-9 on HMG-CoA reductase were tested in vitro. Compounds 1, 7 and 8 showed significant HMG-CoA reductase inhibition with IC₅₀ values of 10.2, 9.72 and 8.68 μM, respectively. The other isolated compounds presented relatively weak inhibitory activity with IC₅₀ values >100 μM. Preliminary structure-activity relationship analysis showed that the HMG moiety in 7 and 8 contributed greatly to their inhibitory activity against HMG-CoA reductase. This work further demonstrates the mushroom G. leucocontextum to be valuable herbal medicine that deserves deep investigation.

Triterpenes and Meroterpenes with Neuroprotective Effects from Ganoderma leucocontextum

Ganoderma leucocontextum is a well-known medicinal mushroom cultivated in the Tibet Plateau of China. Chemistry investigation on the fruiting bodies of this mushroom resulted in the isolation of sixteen secondary metabolites including three new lanostane triterpenes, ganoleucoins Q - S (1 - 3), as well as thirteen known compounds (4 - 16). The structures of compounds 1 - 3 were determined by NMR, MS, CD spectral analysis, and chemical derivation method. The neuroprotective effects of compounds 1 - 16 were tested on PC12 cells. Compounds 1 and 2 showed protective effects against the H₂ O₂ induced damage with the survival rate of 83.19 ± 0.92%, 73.37 ± 1.25% at the concentration of 200 μm, respectively. Meanwhile, compounds 1 and 2 induced neurite outgrowth at 50 - 200 μm. The results from this study suggested that G. leucocontextum and its metabolites may be potential functional food ingredients for the prevention of neurodegenerative diseases.

Lanostane Triterpenoids from Fruiting Bodies of Ganoderma leucocontextum

Six new lanostane-type triterpenoids, namely leucocontextins S-X (1-6), together with twelve known compounds, were isolated from the fruiting bodies of Ganoderma leucocontextum. Their structures were established by MS and NMR data.

(+)- and (−)-ganodilactone, a pair of meroterpenoid dimers with pancreatic lipase inhibitory activities from the macromycete Ganoderma leucocontextum

(+)- and (−)-ganodilactone (1), a pair of novel meroterpenoid dimers possessing a unique 5′H-spiro[chroman-4,2′-furan]-2,5′-dione ring system were discovered from the fruiting bodies of Ganoderma leucocontextum.