Microbial transformation of ginsenoside Rb<Subscript>1</Subscript> by <Emphasis Type="Italic">Acremonium strictum</Emphasis>

Preparative-scale fermentation of ginsenoside Rb₁ (1) with Acremonium strictum AS 3.2058 gave three new compounds, 12β-hydroxydammar-3-one-20 (S)-O-β-d-glucopyranoside (7), 12β, 25-dihydroxydammar-(E)-20(22)-ene-3-O-β-d-glucopyranosyl-(1→2)-β-d-glucopyranoside (8), and 12β, 20 (R), 25-trihydroxydammar-3-O-β-d-glucopyranosyl-(1→2)-β-d-glucopyranoside (9), along with five known compounds, ginsenoside Rd (2), gypenoside XVII (3), ginsenoside Rg₃ (4), ginsenoside F₂ (5), and compound K (6). The structural elucidation of these metabolites was based primarily on one- and two-dimensional nuclear magnetic resonance and high-resolution electron spray ionization mass spectra analyses. Among these compounds, 2–6 are also the metabolites of ginsenoside Rb₁ in mammals. This result demonstrated that microbial culture parallels mammalian metabolism; therefore, A. strictum might be a useful tool for generating mammalian metabolites of related analogs of ginsenosides for complete structural identification and for further use in pharmaceutical research in this series of compounds. In addition, the biotransformation kinetics was also investigated.     

牛痘病毒感染人巨噬细胞基因表达谱的RNA-Seq分析

[目的]利用RNA-Seq,分析人巨噬细胞在牛痘病毒(VACV)感染前后基因表达的变化,探索牛痘病毒与宿主细胞相互作用的机制.[方法]用牛痘病毒感染人巨噬细胞,采用RNA-Seq比较感染组和对照组的差异表达基因,并进行KEGG、GO以及STRING网络分析.[结果]感染组与对照组相比,筛选出显著性差异表达基因4796个...     

Integrative transcriptome analysis identifies new oxidosqualene cyclase genes involved in ginsenoside biosynthesis in Jilin ginseng

BackgroundJilin ginseng, Panax ginseng, is a valuable medicinal herb whose ginsenosides are its major bioactive components. The ginseng oxidosqualene cyclase (PgOSC) gene family is known to play important roles in ginsenoside biosynthesis, but few members of the gene family have been functionally studied.MethodsThe PgOSC gene family has been studied by an integrated analysis of gene expression-ginsenoside content correlation, gene mutation-ginsenoside content association and gene co-expression network, followed by functional analysis through gene regulation.ResultsWe found that five of the genes in the PgOSC gene family, including two published ginsenoside biosynthesis genes and three new genes, were involved in ginsenoside biosynthesis. Not only were the expressions of these genes significantly correlated with ginsenoside contents, but also their nucleotide mutations significantly influenced ginsenoside contents. These results were further verified by regulation analysis of the genes by methyl jasmonate (MeJA) in ginseng hairy roots. Four of these five PgOSC genes were mapped to the ginsenoside biosynthesis pathway. These PgOSC genes expressed differently across tissues, but relatively consistent across developmental stages. These PgOSC genes formed a single co-expression network with those published ginsenoside biosynthesis genes, further confirming their roles in ginsenoside biosynthesis. When the network varied, ginsenoside biosynthesis was significantly influenced, thus revealing the molecular mechanism of ginsenoside biosynthesis.ConclusionAt least five of the PgOSC genes, including the three newly identified and two published PgOSC genes, are involved in ginsenoside biosynthesis. These results provide gene resources and knowledge essential for enhanced research and applications of ginsenoside biosynthesis in ginseng.     

Chemical constituents isolated from Polygala japonica leaves and their inhibitory effect on nitric oxide production in vitro

A methanolic extract of dried leaves of Polygala japonica Houtt (Polygalaceae) significantly attenuated nitric oxide production in lipopolysaccharide-simulated BV2 microglia. Five anthraquinones chrysophanol (1), emodin (2), aloe-emodin (3), emodin 8-O-β-D-glucopyranoside (4) and trihydroxy anthraquinone (5), and four flavonoids kaempferol (6), chrysoeriol (7), kaempferol 3-gentiobioside (8) and isorhamnetin (9) were isolated from the methanolic extract using bioactivity-guided fractionation. Among them, compounds 1–4, 6 and 7 showed significant inhibitory effect on lipopolysaccharide-induced nitric oxide production in BV2 microglia at the concentrations ranging from 1.0 to 100.0 μM.     

Both the mevalonate and the non-mevalonate pathways are involved in ginsenoside biosynthesis

Key Message

When one of them was inhibited, the two pathways could compensate with each other to guarantee normal growth. Moreover, the sterol biosynthesis inhibitor miconazole could enhance ginsenoside level.

Abstract

Ginsenosides, a kind of triterpenoid saponins derived from isopentenyl pyrophosphate (IPP), represent the main pharmacologically active constituents of ginseng. In plants, two pathways contribute to IPP biosynthesis, namely, the mevalonate pathway in cytosol and the non-mevalonate pathway in plastids. This motivates biologists to clarify the roles of the two pathways in biosynthesis of IPP-derived compounds. Here, we demonstrated that both pathways are involved in ginsenoside biosynthesis, based on the analysis of the effects from suppressing either or both of the pathways on ginsenoside accumulation in Panax ginseng hairy roots with mevinolin and fosmidomycin as specific inhibitors for the mevalonate and the non-mevalonate pathways, respectively. Furthermore, the sterol biosynthesis inhibitor miconazole could enhance ginsenoside levels in the hairy roots. These results shed some light on the way toward better understanding of ginsenoside biosynthesis.     

Ginsenoside Rh2 mitigates doxorubicin‐induced cardiotoxicity by inhibiting apoptotic and inflammatory damage and weakening pathological remodelling in breast cancer‐bearing mice

ObjectivesThere are presently a few viable ways to reduce cardiotoxicity of doxorubicin (Dox). The combination of chemotherapy agents with natural compounds delivers greater efficacy and reduces adverse effects in recent researches for cancer treatment. Here, we examined the potential effect of ginsenoside Rh2 on a Dox‐based regimen in chemotherapy treatment.Materials and MethodsHuman breast tumour (MDA‐MB‐231) xenograft nude mice, human cardiac ventricle fibroblasts, and human umbilical vein endothelial cells (HUVEC) were employed in the present study. Histology, immunohistochemistry, immunofluorescence, western blot, antibody array, and RNA‐sequencing analyses were utilized to assess the protective effect of Rh2 on cardiotoxicity induced by Dox and the underlying mechanisms.ResultsRh2‐reduced cardiotoxicity by inhibiting the cardiac histopathological changes, apoptosis and necrosis, and consequent inflammation. Pathological remodelling was attenuated by reducing fibroblast to myofibroblast transition (FMT) and endothelial–mesenchymal transition (EndMT) in hearts. RNA‐sequencing analysis showed that Dox treatment predominantly targets cell cycle and attachment of microtubules and boosted tumour necrosis, chemokine and interferon‐gamma production, response to cytokine and chemokine, and T cell activation, whereas Rh2 regulated these effects. Intriguingly, Rh2 also attenuated fibrosis via promoting senescence in myofibroblasts and reversing established myofibroblast differentiation in EndMT.ConclusionsRh2 regulates multiple pathways in the Dox‐provoked heart, proposing a potential candidate for cancer supplement and therapy‐associated cardiotoxicity.

Doxorubicin is extensively reported to induce severe cardiotoxicity in clinical applications. Our work proposed a natural herbal compound, ginsenoside Rh2, as a potential candidate for attenuating this side effect. Rh2 significantly inhibited cardiac apoptosis and necrosis, inflammation, and pathological remodelling in Dox‐challenged hearts.     

Prognostic value of metabolic genes in lung adenocarcinoma via integrative analyses

BackgroundLung adenocarcinoma (LUAD) is the most common malignant lung tumor. Metabolic pathway reprogramming is an important hallmark of physiologic changes in cancers. However, the mechanisms through which these metabolic genes and pathways function in LUAD as well as their prognostic values have not been fully established.MethodsFour publicly available datasets from GEO and TCGA were used to identify differentially expressed genes (DEGs) in LUAD, which were then subjected to GO and KEGG pathway enrichment analysis. Associations between metabolic gene expressions with overall survival, tumor stage, TP53 mutation status, and infiltrated immune cells were investigated. Protein-protein interactions were evaluated using GeneMANIA and Metascape.ResultsBy integrating four public datasets, 247 DEGs were identified in LUAD. These DEGs were significantly enriched in regulation of chromosome segregation, centromeric region, and histone kinase activity GO terms, as well as in cell cycle, p53 signaling pathway, metabolic pathways, and other KEGG pathways. Elevated expressions of ten metabolic genes in LUAD were significantly associated with poor survival outcomes. These metabolic genes were highly expressed in more advanced tumor stage and TP53 mutated patients. Moreover, expression levels were significantly correlated with tumor-infiltrating immune cells. PPI interaction analysis revealed that the top 20 genes interacting with each metabolic gene were significantly enriched in DNA replication, response to radiation, and central carbon metabolism in cancer.ConclusionThis study elucidates on molecular changes in metabolic genes in LUAD, which may inform the development of genetically oriented diagnostic approaches and effective treatment options.     

Glucose deprivation reversibly down-regulates tissue plasminogen activator via proteasomal degradation in rat primary astrocytes

AimsTissue plasminogen activator (tPA) is an essential neuromodulator whose involvement in multiple functions such as synaptic plasticity, cytokine-like immune function and regulation of cell survival mandates rapid and tight tPA regulation in the brain. We investigated the possibility that a transient metabolic challenge induced by glucose deprivation may affect tPA activity in rat primary astrocytes, the main cell type responsible for metabolic regulation in the CNS.Main methodsRat primary astrocytes were incubated in serum-free DMEM without glucose. Casein zymography was used to determine tPA activity, and tPA mRNA was measured by RT-PCR. The signaling pathways regulating tPA activity were identified by Western blotting.Key findingsGlucose deprivation rapidly down-regulated the activity of tPA without affecting its mRNA level in rat primary astrocytes; this effect was mimicked by translational inhibitors. The down-regulation of tPA was accompanied by increased tPA degradation, which may be modulated by a proteasome-dependent degradation pathway. Glucose deprivation induced activation of PI3K-Akt-GSK3β, p38 and AMPK, and inhibition of these pathways using LY294002, SB203580 and compound C significantly inhibited glucose deprivation-induced tPA down-regulation, demonstrating the essential role of these pathways in tPA regulation in glucose-deprived astrocytes.SignificanceRapid and reversible regulation of tPA activity in rat primary astrocytes during metabolic crisis may minimize energy-requiring neurologic processes in stressed situations. This effect may thereby increase the opportunity to invest cellular resources in cell survival and may allow rapid re-establishment of normal cellular function after the crisis.     

侧脑室微量注射大麻素受体拮抗剂对orexin-A诱导大鼠能量代谢改变的影响及潜在机制研究

目的:探讨大麻素1型受体(CB1)抑制剂利莫那班对下丘脑外侧区(LHA)微量注射orexin-A诱导的小鼠能量代谢及相关行为变化改变的影响。方法:通过侧脑室微量注射(icv)利莫那班,同时LHA微量注射orexin-A,测量小鼠能量代谢、自主运动的变化,杏仁核(CeA)内多巴胺释放能力以及小鼠摄食量的变化。结果:侧脑室微量注射利莫那班可减弱因LHA微量注射orexin-A引起的小鼠能量代谢变化,降低小鼠自主运动,并且减弱小鼠CeA内多巴胺释放能力。注射(icv)利莫那班未改变LHA微量注射orexin-A所诱导的摄食量增多。此外,LHA双侧注射利莫那班可阻断LHA内注射orexin-A对运动活性的促进作用,但不影响小鼠的摄食量。结论:大麻素受体涉及orexin-A诱导的小鼠中脑边缘系统多巴胺系统活化的调控,对能量代谢及自主运动也有影响,但对食物摄入的调节无明显影响。     

Flavonoids exclusively present in mycorrhizal roots of white clover exhibit a different effect on arbuscular mycorrhizal fungi than flavonoids exclusively present in non-mycorrhizal roots of white clover

Abstract

The flavonoids 5,6,7,8,9-hydroxy chalcone, 3,7-hydroxy-4′methoxy flavone, 5,6,7,8-hydroxy-4′-methoxy flavone and 3,5,6,7,4′-hydroxy flavone can be detected only in non-mycorrhizal roots of white clover, but not in mycorrhizal roots, whereas the flavonoids acacetin, quercetin and rhamnetin are only present in mycorrhizal roots. We tested the effect of several concentrations of these compounds on spore germination, hyphal growth, hyphal branching, formation of clusters of auxiliary cells and of secondary spores of the arbuscular mycorrhizal fungi Gigaspora rosea, Gigaspora margarita, Glomus mosseae and Glomus intraradices. Our results indicate that depending on the flavonoid, the tested compounds are involved at different stages in the regulation of mycorrhization. This hypothesis is strengthened by their differing effect on several AM fungal growth parameters. Furthermore, our study provides more data on the AM fungus genus/species specificity of flavonoids.     

Novel targets of pentacyclic triterpenoids in Staphylococcus aureus: A systematic review

BackgroundStaphylococcus aureus is an important pathogen both in community-acquired and healthcare-associated infections, and has successfully evolved numerous strategies for resisting the action to practically all antibiotics. Resistance to methicillin is now widely described in the community setting (CMRSA), thus the development of new drugs or alternative therapies is urgently necessary. Plants and their secondary metabolites have been a major alternative source in providing structurally diverse bioactive compounds as potential therapeutic agents for the treatment of bacterial infections. One of the classes of natural secondary metabolites from plants with the most bioactive compounds are the triterpenoids, which comprises structurally diverse organic compounds. In nature, triterpenoids are often found as tetra- or penta-cyclic structures.AimThis review highlights the anti-staphylococcal activities of pentacyclic triterpenoids, particularly α-amyrin (AM), betulinic acid (BA) and betulinaldehyde (BE). These compounds are based on a 30-carbon skeleton comprising five six-membered rings (ursanes and lanostanes) or four six-membered rings and one five-membered ring (lupanes and hopanes).MethodsElectronic databases such as ScienceDirect, PubMed and Scopus were used to search scientific contributions until March 2018, using relevant keywords. Literature focusing on the antimicrobial and antibiofilms of effects of pentacyclic triterpenoids on S. aureus were identified and summarized.ResultsPentacyclic triterpenoids can be divided into three representative classes, namely ursane, lupane and oleananes. This class of compounds have been shown to exhibit analgesic, immunomodulatory, anti-inflammatory, anticancer, antioxidant, antifungal and antibacterial activities. In studies of the antimicrobial activities and targets of AM, BA and BE in sensitive and multidrug-resistant S. aureus, these compounds acted synergistically and have different targets from the conventional antibiotics.ConclusionThe inhibitory mechanisms of S. aureus in novel targets and pathways should stimulate further researches to develop AM, BA and BE as therapeutic agents for infections caused by S. aureus. Continued efforts to identify and exploit synergistic combinations by the three compounds and peptidoglycan inhibitors, are also necessary as alternative treatment options for S. aureus infections.     

Stress eating and tuning out: Cancer cells re-wire metabolism to counter stress

Abstract

Cancer cells reprogram metabolism to maintain rapid proliferation under often stressful conditions. Glycolysis and glutaminolysis are two central pathways that fuel cancer metabolism. Allosteric regulation and metabolite driven post-translational modifications of key metabolic enzymes allow cancer cells glycolysis and glutaminolysis to respond to changes in nutrient availability and the tumor microenvironment. While increased aerobic glycolysis (the Warburg effect) has been a noted part of cancer metabolism for over 80 years, recent work has shown that the elevated levels of glycolytic intermediates are critical to cancer growth and metabolism due to their ability to feed into the anabolic pathways branching off glycolysis such as the pentose phosphate pathway and serine biosynthesis pathway. The key glycolytic enzymes phosphofructokinase-1 (PFK1), pyruvate kinase (PKM2) and phosphoglycerate mutase 1 (PGAM1) are regulated by upstream and downstream metabolites to balance glycolytic flux with flux through anabolic pathways. Glutamine regulation is tightly controlled by metabolic intermediates that allosterically inhibit and activate glutamate dehydrogenase, which fuels the tricarboxylic acid cycle by converting glutamine derived glutamate to α-ketoglutarate. The elucidation of these key allosteric regulatory hubs in cancer metabolism will be essential for understanding and predicting how cancer cells will respond to drugs that target metabolism. Additionally, identification of the structures involved in allosteric regulation will inform the design of anti-metabolism drugs which bypass the off-target effects of substrate mimics. Hence, this review aims to provide an overview of allosteric control of glycolysis and glutaminolysis.     

Essential oils and its bioactive compounds modulating cytokines: A systematic review on anti-asthmatic and immunomodulatory properties

BackgroundAsthma, the main inflammatory chronic condition affecting the respiratory system, is characterized by hyperresponsiveness and reversible airway obstruction, recruitment of inflammatory cells and excessive production of mucus. Cytokines as biochemical messengers of immune cells, play an important role in the regulation of allergic inflammatory and infectious airway processes. Essential oils of plant origin are complex mixtures of volatile and semi volatile organic compounds that determine the specific aroma of plants and are categorized by their biological activities.PurposeWe reviewed whether essential oils and their bioactive compounds of plant origin could modulate cytokines’ immune responses and improve asthma therapy in experimental systems in vitro and in vivo.MethodsElectronic and manual search of articles in English available from inception up to November 2018 reporting the immunomodulatory activity of essential oils and their bioactive compounds for the management of asthma. We used PubMed, EMBASE, Scopus and Web of Science. Publications reporting preclinical experiments where cytokines were examined to evaluate the consequence of anti-asthmatic therapy were included.Results914 publications were identified and 13 were included in the systematic review. Four articles described the role of essential oils and their bioactive compounds on bronchial asthma using cell lines; nine in vivo studies evaluated the anti-inflammatory efficacy and immunomodulating effects of essential oil and their secondary metabolites on cytokines production and inflammatory responses. The most important immunopharmacological mechanisms reported were the regulation of cytokine production, inhibition of reactive oxygen species accumulation, inactivation of eosinophil migration and remodeling of the airways and lung tissue, modulation of FOXP3 gene expression, regulation of inflammatory cells in the airways and decreasing inflammatory mediator expression levels.ConclusionPlant derived essential oils and related active compounds have potential therapeutic activity for the treatment of asthma by modulating the release of pro-inflammatory (TNF-α, IL-1β, IL-8), Th17 (IL-17), anti-inflammatory (IL-10), Th1 (IFN-γ, IL-2, IL-12) and Th2 (IL-4, IL-5, IL-6, IL-13) cytokines and the suppression of inflammatory cell accumulation.     

Network pharmacology and pharmacokinetics integrated strategy to investigate the pharmacological mechanism of Xianglian pill on ulcerative colitis

BackgroundUlcerative colitis (UC) is a chronic inflammatory bowel disease with high morbidity, which leads to poor quality of life. The Xianglian pill (XLP) is a classical Chinese patent medicine and has been clinically proven to be an effective treatment for UC.PurposeThe pharmacological mechanism of the key bioactive ingredients of XLP for the treatment of UC was investigated by a network pharmacology and pharmacokinetics integrated strategy.Study design and methodsNetwork pharmacology was used to analyze the treatment effect of nine quantified XLP ingredients on UC. Key pathways were enriched and analyzed by protein-protein interaction and Kyoto Encyclopedia of Genes and Genomes analyses. The effect of XLP on Th17 cell differentiation was validated using a mouse model of UC. The binding of nine compounds with JAk2, STAT3, HIF-1α, and HSP90AB1 was assessed using molecular docking. A simple and reliable ultra-high-performance liquid chromatography-tandem mass spectrometry method was developed for the simultaneous quantification of nine ingredients from XLP in plasma and applied to a pharmacokinetic study following oral administration.ResultsNine compounds of XLP, including coptisine, berberine, magnoflorine,berberrubine, jatrorrhizine, palmatine, evodiamine, rutaecarpine, and dehydrocostus lactone, were detected. Network pharmacology revealed 50 crossover genes between the nine compoundsand UC. XLP treats UC mainly by regulating key pathways of the immune system, including Th17 cell differentiation, Jak-Stat, and PI3K-Akt signaling pathways. An in vivo validation in mice found that XLP inhibits Th17 cell differentiation by suppressing the Jak2-Stat3 pathway, which alleviates mucosal inflammation in UC. Molecular docking confirmed that eight compounds are capable of binding with JAk2, HIF-1α, and HSP90AB1, further confirming the inhibitory effect of XLP on the Jak2-Stat3 pathway. Moreover, apharmacokinetic study revealed that the nine ingredients of XLP are exposed in the plasma and colon tissue, which demonstrates its pharmacological effect on UC.ConclusionThis study evaluates the clinical treatment efficacy of XLP for UC. The network pharmacology and pharmacokinetics integrated strategy evaluation paradigm is efficient in discovering the key pharmacological mechanism of herbal formulae.     

Antioxidant properties of flavonol glycosides from tea

Abstract

We have determined the antioxidant activity of the major flavonols found in tea: a monoglycoside, a diglycoside and two triglycosides of kaempferol and three monoglycosides, a diglycoside and two triglycosides of quercetin. The Trolox equivalent antioxidant capacity (TEAC) and inhibition of iron/ascorbate-induced lipid peroxidation of phosphatidyl choline vesicles were measured. In the aqueous phase TEAC assay, the quercetin monoglycosides and diglycoside were approximately half as effective as quercetin aglycone. The quercetin triglycosides were much less effective than the mono-glycosides and the diglycoside. The kaempferol glycosides were 32–9% less effective in the aqueous phase antioxidant assay compared to the kaempferol aglycone. Quercetin monoglycosides and diglycoside were potent inhibitors of lipid peroxidation, in contrast to the triglycoside which was much less effective. All the kaempferol glycosides were significantly less potent inhibitors of lipid peroxidation compared to the kaempferol aglycone. The compounds described herein demonstrate the antioxidant activity of the major flavonols in tea and indicate the effect of substituting a range of sugar moieties in the phenolic C ring.     

Regulation of Sugar and Ethanol Metabolism in Saccharomyces cerevisiae

Abstract

This review briefly surveys the literature on the nature, regulation, genetics, and molecular biology of the major energy-yielding pathways in yeasts, with emphasis on Sacchuromyces cerevisiae. While sugar metabolism has received the lion's share of attention from workers in this field because of its bearing on the production of ethanol and other metabolites, more attention is now being paid to ethanol metabolism and the regulation of aerobic metabolism by fermentable and non-fermentable substrates. The utility of yeast as a highly manipulable organism and the discovery that yeast metabolic pathways are subject to the same types of control as those of higher cells open up many opportunities in such diverse areas as molecular evolution and cancer research.     

红树林植物瓶花木中的细胞毒活性成分(Ⅱ)

从红树林树植物瓶花木(Scyphiphora hydrophyllacea Gaertn. f.)的乙醇提取物中分离得到5个化合物,通过波谱分析,鉴定其结构分别为:shanzhigenin methyl ester (1)、1-epishanzhigenin methyl ester (2)、山柰酚 (3)、芹菜素 (4)和 5,7,2'-trihydroxy-3,6,8,4',5'-pentamethoxyflavone (5)。以上化合物均为首次从瓶花木中分离得到。细胞毒活性测试结果表明,化合物1和2的混合物对人肝癌细胞(SMMC-7721)的增殖有较强的生长抑制活性。