Polyprodrug nanomedicine for chemiexcitation-triggered self-augmented cancer chemotherapy and gas therapy.

Carbon monoxide (CO) has emerged as a potential antitumor agent by inducing the dysfunction of mitochondria and the apoptosis of cancer cells. However, it remains challenging to deliver appropriate amount of CO into tumor to ensure efficient tumor growth suppression with minimum side effects. Herein we developed a CO prodrug-loaded nanomedicine based on the self-assembly of camptothecin (CPT) polyprodrug amphiphiles. The polyprodrug nanoparticles readily dissociate upon exposure to endogenous H2O2 in the tumor, resulting in rapid release of CPT and generation of high-energy intermediate dioxetanedione. The latter can transfer the energy to neighboring CO prodrugs to activate CO production by chemiexcitation, while CPT promotes the generation of H2O2 in tumors, which in turn facilitates cascade CPT and CO release. As a result, the polyprodrug nanoparticles display remarkable tumor suppression in both subcutaneous and orthotopic breast tumor-bearing mice owing to the self-augmented CPT release and CO generation. In addition, no obvious systemic toxicity was observed in mice treated with the metal-free CO prodrug-loaded nanomedicine, suggesting the good biocompatibility of the polyprodrug nanoparticles. Our work provides new insights into the design and construction of polyprodrug nanomedicines for synergistic chemo/gas therapy.

Synthesis of Organopolysilazane Nanoparticles as Lithium-Ion Battery Anodes with Superior Electrochemical Performance via the Two-Step Stöber Method.

The Stöber method, a widely utilized sol-gel technique, stands as a green and reliable approach for preparing nanostructures on a large scale. In this study, we employed an enhanced Stöber method to synthesize organopolysilazane nanoparticles (OPSZ NPs), utilizing polysilazane oligomers as the primary precursor material and ammonia as the catalytic agent. By implementing a two-step addition process, control over crucial parameters facilitated the regulation of the nanoparticle size. Generally, maintaining relatively low concentrations of organopolysilazane and catalyst while adjusting the water/acetonitrile ratio can effectively enhance the surface energy of the organopolysilazane, resulting in the uniform formation of small spherical particles. The average particle size of the synthesized OPSZ NPs is about 140 nm, which were monodispersed and characterized by scanning electron microscopy, transmission electron microscopy, and dynamic light scattering. Furthermore, the composition of OPSZ NPs after pyrolysis was confirmed as SiC2.054N0.206O1.631 with 5.44 wt % free carbon structure by X-ray diffraction and energy-dispersive X-ray spectroscopy. Notably, the electrochemical performance assessment of SiCNO NPs as potential electrode materials for lithium-ion batteries exhibited promising outcomes. Specifically, at 1 A g-1 current density, the specific capacity is 585.45 mA h g-1 after 400 cycles, and the minimum capacity attenuation per cycle is only 0.1076 mA h g-1 (0.0172% of the original capacity), which indicates excellent energy storage capacity and cycle stability. In summary, this research contributes to the development of advanced anode materials for next-generation energy storage systems, marking a stride toward sustainable energy solutions.

Two new megastigmane glycosides from the leaves of Nicotiana tabacum and their anti-inflammatory activities.

Two new megastigmane glycosides, (6 R,7E,9R)-3-oxo-α-ionyl-9-O-α-L-rhamnopyranosyl-(1''→4')-ß-D-glucopyranoside (1) and (6 R,7E,9R)-3-oxo-α-ionyl-9-O-ß-D-glucopyranosyl-(1''→6')-ß-D-glucopyranoside (2), together with six known analogues (3-8) were isolated from the leaves of Nicotiana tabacum. The structures of all metabolites were determined by comprehensive analysis of NMR and MS spectroscopic data as well as by comparison with those of previously reported. The in vitro anti-inflammatory activity of all isolates was evaluated using a lipopolysaccharide (LPS)-induced RAW264.7 cell inflammatory model, and the compounds 1, 3, 7, and 8 exhibited inhibition of LPS-induced NO production in RAW264.7 macrophage cells with IC50 values of 42.3-61.7 µM (positive control, dexamethasone, IC50 = 21.3 ± 1.2 µM).

Aliphatic Hyperbranched Polycarbonates Solid Polymer Electrolytes with High Li-Ion Transference Number for Lithium Metal Batteries.

In this work, hyperbranched polycarbonate-poly(ethylene oxide) (PEO)-based solid polymer electrolytes (HBPC-SEs) are successfully synthesized via a straightforward organo-catalyzed "A1"+"B2"-ring-opening polymerization approach. The temperature-dependent ionic conductivity of HBPC-SEs, composed of different polycarbonate linkages and various LiTFSI concentrations, is investigated. The results demonstrate that HBPC-SE with an ether-carbonate alternating structure exhibits superior ionic conductivity, attributed to the solubility of Li salts in the polymer matrix and the mobility of the polymer segments. The HBPC1-SE with 30 wt% LiTFSI presents the highest ionic conductivities of 2.15  × 10-5, 1.78 × 10-4, and 6.07 × 10-4 Scm-1 at 30, 60, and 80 °C, respectively. Compared to traditional PEO-based electrolytes, the incorporation of polycarbonate segments significantly enhances the electrochemical stability window (5 V) and Li+ transference number (0.53) of HBPC-SEs. Furthermore, the LiFePO4/HBPC1-SE-3/Li cell exhibits exceptional rate capability and long-cycling performance, maintaining a discharge capacity of 130 mAh g-1 at 0.5C with a capacity retention of 95% after 300 cycles.

Targeted therapies of inflammatory diseases with intracellularly gelated macrophages in mice and rats.

Membrane-camouflaged nanomedicines often suffer from reduced efficacy caused by membrane protein disintegration and spatial disorder caused by separation and reassembly of membrane fragments during the coating process. Here we show that intracellularly gelated macrophages (GMs) preserve cell membrane structures, including protein content, integration and fluidity, as well as the membrane lipid order. Consequently, in our testing GMs act as cellular sponges to efficiently neutralize various inflammatory cytokines via receptor-ligand interactions, and serve as immune cell-like carriers to selectively bind inflammatory cells in culture medium, even under a flow condition. In a rat model of collagen-induced arthritis, GMs alleviate the joint injury, and suppress the overall arthritis severity. Upon intravenous injection, GMs efficiently accumulate in the inflammatory lungs of acute pneumonia mice for anti-inflammatory therapy. Conveniently, GMs are amenable to lyophilization and can be stored at ambient temperatures for at least 1 month without loss of integrity and bio-activity. This intracellular gelation technology provides a universal platform for targeted inflammation neutralization treatment.

Comparative clinical study of the modified Broström procedure for the treatment of the anterior talofibular ligament injury-outcomes of the open technique compared to the arthroscopic procedure.

PURPOSE: To observe the clinical efficacy and safety of arthroscopic-modified Broström surgery for the treatment of anterior talofibular ligament injury. METHODS: The clinical data of 51 cases with anterior talofibular ligament injury were retrospectively analyzed, in which 23 patients were treated by arthroscopic-modified Broström surgery (arthroscopic surgery group) and 28 patients were treated by open-modified Broström surgery (open surgery group). The time to surgery, hospital stay, visual analog scale (VAS) scores of ankle pain, American Orthopaedic Foot and Ankle Society (AOFAS) ankle and hindfoot scores, and incidence rate of complications were compared between the two groups. RESULTS: (1) General results: compared with open surgery group, arthroscopic surgery group had shorter time to surgery and hospital stay ((33.8 ± 6.7) min, (42.1 ± 8.5) min, t = 1.468, P = 0.001; (2.2 ± 1.4) d, (5.8 ± 1.6) d, t = 1.975, P = 1.975, P = 0.002). (2) VAS scores of ankle pain: there was an interaction effect between the time and group factors (F = 0.378, P = 0.018); overall, there was no statistically significant difference in VAS scores of ankle pain between the two groups, i.e., there was no grouping effect (F = 1.865, P = 0.163); there was statistically significant difference in VAS score of ankle pain at different time points before and after operation, i.e., there was a time effect (F = 1.675, P = 0.000); the VAS scores of ankle pain showed a decreasing trend with time in both groups, but the decreasing trend was not completely consistent between the two groups ((7.78 ± 1.23), (1.23 ± 1.24), (1.03 ± 0.35), (1.01 ± 0.28), F = 0.568, P = 0.000. (7.45 ± 1.43), (1.45 ± 1.87), (1.23 ± 0.55), (1.04 ± 0.37), F = 1.358, P = 0.000); there was no statistically significant difference in VAS score of ankle joint pain between the two groups six and 12 months before and after surgery (t = 2.987, P = 0.055; t = 1.654, P = 2.542; t = 0.015, P = 0.078); the VAS scores of ankle pain in the arthroscopic surgery group was lower than that in the open surgery group three months after operation (t = 1.267, P = 0.023). (3) AOFAS ankle and hindfoot scores: there was an interaction effect between time and grouping factors (F = 2.693, P = 0.027); overall, there was no statistically significant difference in the AOFAS ankle and hindfoot scores between the two groups, i.e., there was no grouping effect (F = 1.983, P = 0.106); there was statistically significant difference in the AOFAS ankle and hindfoot scores at different time points before and after surgery, i.e., there was a time effect (F = 34.623, P = 0.000); the AOFAS ankle and hindfoot scores of the two groups showed an increasing trend with time, but the increasing trend of the two groups was not completely consistent ((48.19 ± 12.89), (89.20 ± 8.96), (90.24 ± 7.89), (91.34 ± 9.67), F = 25.623, P = 0.000; (49.35 ± 13.28), (86.78 ± 12.34), (88.78 ± 9.78),(91.43 ± 7.98), F = 33.275, P = 0.000); there was no statistically significant difference in the AOFAS ankle and hindfoot scores between the two groups 12 months before/after surgery (t = 2.145，P = 0.056；t = 2.879，P = 0.389); compared with open surgery group, the arthroscopic surgery group had higher AOFAS ankle and hindfoot scores 3/6 months after surgery (t = 1.346, P = 0.014; t = 1.874, P = 0.028). CONCLUSION: For the treatment of anterior talofibular ligament injury, arthroscopic surgery group is superior to open surgery group in ankle pain relief and functional recovery and has shorter operation time and hospital stay compared with open surgery group.

Paeoniflorin, the Main Monomer Component of Paeonia lactiflora, Exhibits Anti-inflammatory Properties in Osteoarthritis Synovial Inflammation.

OBJECTIVE: To explore the mechanism of paeoniflorin (PF) on osteoarthritis (OA) synovial inflammation from network pharmacology to experimental pharmacology. METHODS: Targets of OA were constructed by detecting the database of network database platforms (Therapeutic Target database, DrugBank and GeneCards), and the targets of PF were constructed by PubChem and Herbal Ingredients' Targets database. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis of these co-targeted genes were conducted via Database for Annotation, Visualization, and Integrated Discovery (DAVID) database, and protein-protein interaction (PPI) networks were conducted via the search tool for the retrieval of interacting genes (STRING) database. Cell counting kit-8 (CCK-8) assay was performed to assess the potential toxicity of PF on human OA fibroblast-like synoviocytes (FLS), quantitative real-time polymerase chain reaction (qPCR), enzyme-linked immunosorbent assay (ELISA) and Western blot were used to verify the potential mechanism of PF in synovial inflammation. RESULTS: Twenty-six co-targeted genes were identified. GO enrichment results showed that these co-targeted genes were most likely localized in the cytoplasm, and the biological processes mainly involved 'cellular response to hypoxia' 'lipopolysaccharide (LPS)-mediated signaling pathway' and 'positive regulation of gene expression'. KEGG pathway analysis indicated that these co-targeted genes may function through pathways associated with 'hypoxia-inducible factor-1 (HIF-1) signaling pathway' and 'tumor-necrosis factor (TNF) signaling pathway'. The PPI network showed that the top 3 hub genes were TP53, TNF, and CASP3. Molecular docking results showed that PF was well docking with TNF. CCK-8 showed no potential toxicity of 10, 20 and 50 µmol/L PF on human OA FLS. And PF significantly decreased the expression levels of interleukin-1 ß, interleukin-6, TNF-α matrix metalloproteinase 13 (MMP13), and a disintegrin and metalloproteinase with thrombospondin motifs 5 (ADAMTS5) and TNF-α in LPS-induced OA FLS. CONCLUSION: PF exhibited potent anti-inflammatory effect in OA synovial inflammation.

Synthesis of Functional Isosorbide-Based Polyesters and Polyamides by Passerini Three-Component Polymerization.

Environmental issues are becoming more and more prominent, and bio-based polymers are essential to alleviate environmental degradation by replacing traditional polymers. With this context, a new family of functional isosorbide-based polyesters and polyamides with high glass transition temperature are prepared via Passerini-Three component polymerization (P-3CP). To optimize the P-3CP conditions, the influence of the polymerization solvent, temperature, feed ratio on the molar mass of final polymers are investigated. The higher molar mass (up to 10100 g/mol) and yield (>70 %) are achieved under very mild conditions (30 °C, standard atmosphere). Functional side groups, such as alkenyl, alkynyl and methyl ester, were introduced into polymer structure via P-3CP by using functional isocyanides. The obtained polyesters and polyamides are characterized by nuclear magnetic resonance (NMR) and infrared (IR) spectroscopies, differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). All polymers are thermal stable and amorphous with variable glass transition temperatures (Tg ). The obtained polyester has Tg up to 87.5 °C, while the Tg of polyamides (ISPA-2) is detected to be 97.5 °C depending on the amide bonds in the polymer backbone and the benzene ring side groups. The cytotoxicity is investigated by the CCK-8 assay against mBMSC cells to confirm the biological safety. Overall, this novel strategy provides an efficient approach to produce functional isosorbide-based polyesters and polyamides, which are promising prospect for being applied to biodegradable materials.

Application of titanium 3D-printed double-sleeve guide for zygomatic implants: A technique report.

The unique anatomical structure of the atrophic edentulous maxilla limits the placement of endosteal root form dental implants without bone grafting and augmentation. Surgical placement of zygomatic implants in an optimal position remains challenging. This technique report illustrates a novel digital guide technology, including the design workflow, application method, and indications for assisting with the placement of zygomatic implants using a bone-supported titanium double-sleeve guide. In addition, when the implant body reaches the zygomatic bone following an intra-sinus path, including ZAGA type 0 and ZAGA type 1 cases, a matching window osteotomy surgical guide is used to locate the lateral window boundary and protect the sinus membrane. With this technique, the surgical procedure is simplified, and the precision of guided zygomatic implant placement is improved.

Preparation of PFPE-Based Polymeric Nanoparticles via Polymerization-Induced Self-Assembly as Contrast Agents for 19F MRI.

Fluorine-19 magnetic resonance imaging (19F MRI) probes have received considerable research interest as imaging contrast agents (CAs), but they remain neglected and underutilized due to the limited fluorine content or poor performance of fluorinated tracers. Here, we present polymeric nanoparticles (NPs) as 19F MRI CAs with a simple synthesis method and promising imaging performance. First, hydrophilic random copolymers were synthesized from oligo(ethylene glycol) methyl ether acrylate and perfluoropolyether methacrylate by reversible addition-fragmentation chain transfer (RAFT) polymerization. The optimal fluorine content, polymer concentration, and cytotoxicity as 19F MRI CAs were investigated in detail. Then, the optimal copolymer was selected as the macromolecular chain transfer agent, and the chain extension was performed with 2-(perfluorooctyl ethyl methacrylate). Subsequently, the NPs with different morphologies, such as ellipsoidal, spherical nanoparticles and vesicles, were prepared in situ by the RAFT-mediated polymerization-induced self-assembly method. In addition, the 19F MRI signal and cytotoxicity studies further confirmed that these polymeric NPs are nontoxic and have great potential as promising 19F MRI CAs for biological applications.

Photo-Responsive Self-Assembled Polymeric Nanoparticle Probes for 19F MRI Theranostics.

19F magnetic resonance imaging (MRI)-assisted drug delivery provides the possibility to monitor and track drug transportation details in situ. A series of photo-responsive amphiphilic block copolymers consisting of hydrophilic poly(ethylene glycol) and 19F-containing hydrophobic segments, poly(2,2,2-trifluoroethyl acrylate) (PTFEA), with different chain lengths were synthesized by reversible addition-fragmentation chain-transfer polymerization. In particular, the photo-sensitive functional group of o-nitrobenzyl oxygen was introduced to control the photolysis behavior of the copolymers under ultraviolet irradiation. With the extension of the hydrophobic chain length, the drug loading capacity and photoresponsivity were both enhanced, while the chain mobility of PTFEA was suppressed, and the 19F MRI signal was attenuated. When the polymerization degree of PTFEA was about 10, the nanoparticles exhibit detectable 19F MRI signals and sufficient drug loading capacity (loading efficiency = 10%, cumulative release = 49%). These results offer a promising "smart" theranostic platform for 19F MRI.

ED90 of epidural esketamine with 0.075% ropivacaine for labor analgesia in nulliparous parturients: a prospective, randomized and dose-finding study.

Background: Because it has been reported that racemic ketamine had a local anesthetic-sparing effect when used for epidural analgesia this would suggest the likelihood of a potential advantage (less pruritus) over opioid drugs. Esketamine has greater analgesic efficacy than racemic ketamine, but the optimum dosage regimen for epidural use is undetermined. The aim of this study was to determine the ED90 of epidural esketamine when coadministered with 0.075% ropivacaine for labor analgesia. Methods: A total of 65 laboring nulliparous patients were enrolled in this study from 16 March 2022 to 15 October 2022. The patients were randomly assigned to receive 0, 0.25, 0.5, 0.75 or 1.0 mg/mL esketamine with 0.075% ropivacaine epidurally. An effective response to the epidural loading dose was defined as numerical rating scale pain score ≤3 at 30 min after the end of the epidural loading dose (10 mL of the ropivacaine 0.075% solution with the added esketamine). The ED90 of epidural esketamine coadministered with 0.075% ropivacaine with 95% confidence intervals for labor analgesia was determined using probit regression. Secondary outcomes and side effects were recorded. Results: The estimated value of ED90 with 95% CIs for epidural esketamine with 0.075% ropivacaine was 0.983 (0.704-2.468) mg/mL. The characteristics of sensory and motor block, consumption of ropivacaine per hour, duration of first or second stage, Apgar scores did not differ among the five groups. The incidence of mild dizziness in Group esketamine 1.0 mg/mL was significantly higher than that in other groups (p < 0.05). No statistical differences were found in other side effects among groups. Conclusion: The ED90 value of epidural esketamine coadministered with 0.075% ropivacaine for labor analgesia in nulliparous parturients was about 1.0 mg/mL. Furthermore, our results suggested that epidural esketamine would cause dose-dependent mild dizziness especially at doses up to 1.0 mg/mL. As a single epidural additive, esketamine may not be suitable for labor analgesia. Future studies may investigate the appropriate dosage of esketamine at slightly higher concentrations of local anesthetics or larger initial volume of analgesia, or explore other potential advantages of esketamine. Clinical Trial Registration: (https://www.chictr.org.cn/bin/project/edit?pid=159764), identifier (ChiCTR2200057662).

Exosome-Modified Liposomes Targeted Delivery of Thalidomide to Regulate Treg Cells for Antitumor Immunotherapy.

Thalidomide (THD), a synthetic derivative of glutamic acid, was initially used as a sedative and antiemetic until the 1960s, when it was found to cause devastating teratogenic effects. However, subsequent studies have clearly demonstrated the anti-inflammatory, anti-angiogenic, and immunomodulatory properties of thalidomide, thus providing a rationale for its current use in the treatment of various autoimmune diseases and cancers. Our group found that thalidomide can suppress the regulatory T cells (Tregs), a minor subset of CD4+ T cells (~10%) with unique immunosuppressive activity that have been shown to accumulate in the tumor microenvironment (TME) and represent a major mechanism of tumor immune evasion. Due to the low solubility of thalidomide in its present form of administration, coupled with its lack of specificity for targeted delivery and controlled drug release, it is an urgent need to find potent delivery methods that can significantly enhance its solubility, optimize the desired site of drug action, and mitigate its toxicity. In this study, the isolated exosomes were incubated with synthetic liposomes to form hybrid exosomes (HEs) that carried THD (HE-THD) with uniform size distribution. The results demonstrated that HE-THD could significantly abrogate the expansion and proliferation of Tregs induced by TNF, and this might result from blocking TNF-TNFR2 interaction. By encapsulating THD in hybrid exosomes, our drug delivery system successfully increased the solubility of THD, laying a foundation for future in vivo experiments that validate the antitumor activity of HE-THD by reducing the Treg frequency within the tumor microenvironment.

Conjugation of Macrophage-Mimetic Microalgae and Liposome for Antitumor Sonodynamic Immunotherapy via Hypoxia Alleviation and Autophagy Inhibition.

Sonodynamic therapy (SDT) is a noninvasive technique for local antitumor treatment; however, its clinical application is often limited by the low tumor accumulation of SDT agents, tumor's hypoxic microenvironment, and cytoprotective effects of autophagy. To address these issues, herein we developed surface-engineered chlorella (Chl, a green algae) as a targeted drug carrier and sustainable oxygen supplier (via photosynthesis) for significantly improved SDT via hypoxia alleviation as well as autophagy inhibition of chloroquine phosphate. In this design, the macrophage membrane was coated onto Chl to form macrophage-mimetic Chl (MChl) to increase its biocompatibility and targeted tumor accumulation driven by the inflammatory-homing effects of macrophage membranes. In addition, the membrane coating on Chl allowed lipid insertion to yield ß-cyclodextrin (ß-CD) modified MChl (CD-MChl). Subsequently, supramolecular conjugates of MChl-NP were constructed via host-guest interactions between CD-MChl and adamantane (ADA)-modified liposome (ADA-NP), and the anchored liposome went with CD-MChl hand-in-hand to the tumor tissues for co-delivery of Chl, hematoporphyrin, and chloroquine phosphate (loaded in ADA-NP). The synergistic therapy achieved via local oxygenation, SDT, and autophagy inhibition maximally improved the therapeutic efficacy of MChl-CQ-HP-NP against melanoma. Tumor rechallenging results revealed that the changes of tumor microenvironment including hypoxia alleviation, SDT induced immunogenic cell death, and autophagy inhibition collectively induced a strong antitumor immune response and memory.

An intelligent, autocatalytic, DNAzyme biocircuit for amplified imaging of intracellular microRNAs.

DNAzymes hold great promise as transducing agents for the analysis of intracellular biomarkers. However, their low intracellular delivery efficiency and limited signal amplification capability (including an additional supply of cofactors) hinder their application in low-abundance biomarker analysis. Herein, a general strategy to design an intelligent, autocatalytic, DNAzyme biocircuit is developed for amplified microRNA imaging in living cells. The DNAzyme biocircuit is constructed based on a nanodevice composed of catalytic hairpin assembly (CHA) and DNAzyme biocatalytic functional units, sustained by Au nanoparticles (AuNPs) and MnO2 nanosheets (CD/AM nanodevices). Once the CD/AM nanodevices are endocytosed by cells, the MnO2 nanosheets are reduced by intracellular glutathione (GSH), which not only releases the different units of the DNAzyme circuit, but also generates the cofactor Mn2+ for DNAzyme autocatalysis. The intracellular analytes could trigger the coordinated cross-activation of CHA and autocatalytic DNAzymes on AuNPs, enabling reliable and accurate detection of miRNAs in living cells. This intelligent autocatalytic multilayer DNAzyme biocircuit can effectively avoid signal leakage and obtain high amplification gain, expanding the application of programmable complex DNA nanocircuits in biosensing, nanomaterial assembly, and biomedicine.

Effects of total sleep deprivation on execution lapses during vigilance tasks.

Total sleep deprivation (TSD) results in reduced efficiency of cognitive resources. Moreover, when the available cognitive resources are less than required, individuals exhibit lapses in responsiveness. Accordingly, this study explored the effects of TSD on executive function and the characteristics of execution lapses. Functional near-infrared spectroscopy was used to monitor the prefrontal cortex's functional connections in resting and tasking states for various sleep deprivation durations. Data from participants' attentional performance test and self-reported fatigue were collected over 30 hours of wakefulness. Task performance was compared based on time of day, time on task, and reaction time. The results show that participants' arousal level significantly decreased post 14 hours (P < .05), while sleepiness increased. The prefrontal cortex connection and attentional performance dropped at the Window of Circadian Low (3:00 ~ 6:00). The number of execution lapses was higher during the initiation, inhibition, and fatigue phases and rose markedly post 14 hours of wakefulness. We conclude that maintaining better inhibition control requires a reasonable extension of the reaction time. Moreover, subjective perception is significantly correlated with task performance and right prefrontal connection strength. This study presents the scientific evidence for measures to address consistently long working hours and disrupted circadian rhythms.

Antioxidant Properties of Triterpenoids Isolated from Bagasse-Cultivated Lingzhi or Reishi Medicinal Mushroom, Ganoderma lucidum (Agaricomycetes), at Different Developmental Stages.

Although triterpenoids are one of the main active ingredients in Ganoderma lucidum, their accumulation and antioxidant activity during the different developmental stages of G. lucidum cultivation in bagasse remains unclear. In this study, we investigated the content and antioxidant activity of total triterpenoids extracted from G. lucidum strain GL102 during the five growth stages. The obtained results showed that the highest content (12.06 mg/g) was detected in stage 3 (young fruiting body), similar to the contents of ganoderic acids B and G. However, ganoderic acids A and D exhibited maximal contents in stage 5 (spore-ejected fruiting body). The triterpenoids extracted during stage 5 were most capable of scavenging DPPH, OH, and ABTS(+) radicals, with scavenging rates of 65.88%, 86.45%, and 97.91%, respectively. Based on in vivo antioxidant assays conducted on zebrafish, the safe concentration of these triterpenoids was 0.03 mg/mL. At this concentration, the G. lucidum triterpenoids extracted during stage 5 could decrease lipopolysaccharide-induced intracellular reactive oxygen species to a level that was nearly normal (similar to the control group). The accumulation profile and antioxidant activity results reported herein provide the scientific basis needed to promote the utilization of triterpenoids derived from bagasse-cultivated G. lucidum.

Gllac7 Is Induced by Agricultural and Forestry Residues and Exhibits Allelic Expression Bias in Ganoderma lucidum.

Ganoderma lucidum has a wide carbon spectrum, while the expression profile of key genes relevant to carbon metabolism on different carbon sources has been seldom studied. Here, the transcriptomes of G. lucidum mycelia cultured on each of 19 carbon sources were conducted. In comparison with glucose, 16 to 1,006 genes were upregulated and 7 to 1,865 genes were downregulated. Significant gene expression dynamics and induced activity were observed in laccase genes when using agricultural and forestry residues (AFRs) as solo carbon sources. Furthermore, study of laccase gene family in two haploids of G. lucidum GL0102 was conducted. Totally, 15 and 16 laccase genes were identified in GL0102_53 and GL0102_8, respectively, among which 15 pairs were allelic genes. Gene structures were conserved between allelic laccase genes, while sequence variations (most were SNPs) existed. Nine laccase genes rarely expressed on all the tested carbon sources, while the other seven genes showed high expression level on AFRs, especially Gllac2 and Gllac7, which showed 5- to 1,149-fold and 4- to 94-fold upregulation in mycelia cultured for 5 days, respectively. The expression of H53lac7 was consistently higher than that of H8lac7_1 on all the carbon sources except XM, exhibiting a case of allelic expression bias. A total of 47 SNPs and 3 insertions/deletions were observed between promoters of H53lac7 and H8lac7_1, which lead to differences in predicted binding sites of zinc fingers. These results provide scientific data for understanding the gene expression profile and regulatory role on different carbon sources and may support further functional research of laccase.