Discovery of plant chemical defence mediated by a two-component system involving β-glucosidase in Panax species

Plants usually produce defence metabolites in non-active forms to minimize the risk of harm to themselves and spatiotemporally activate these defence metabolites upon pathogen attack. This so-called two-component system plays a decisive role in the chemical defence of various plants. Here, we discovered that Panax notoginseng, a valuable medicinal plant, has evolved a two-component chemical defence system composed of a chloroplast-localized β-glucosidase, denominated PnGH1, and its substrates 20(S)-protopanaxadiol ginsenosides. The β-glucosidase and its substrates are spatially separated in cells under physiological conditions, and ginsenoside hydrolysis is therefore activated only upon chloroplast disruption, which is caused by the induced exoenzymes of pathogenic fungi upon exposure to plant leaves. This activation of PnGH1-mediated hydrolysis results in the production of a series of less-polar ginsenosides by selective hydrolysis of an outer glucose at the C-3 site, with a broader spectrum and more potent antifungal activity in vitro and in vivo than the precursor molecules. Furthermore, such β-glucosidase-mediated hydrolysis upon fungal infection was also found in the congeneric species P. quinquefolium and P. ginseng. Our findings reveal a two-component chemical defence system in Panax species and offer insights for developing botanical pesticides for disease management in Panax species.

Total saponins from Panax japonicus attenuate acute alcoholic liver oxidative stress and hepatosteatosis by p62-related Nrf2 pathway and AMPK-ACC/PPARα axis in vivo and in vitro

ETHNOPHARMACOLOGICAL RELEVANCE

Panax japonicus (T. Nees) C.A. Mey. (PJ) has been used as a tonic traditional Chinese medicine (TCM) for years. Based on its meridian tropism in liver, spleen, and lung, PJ was popularly used to enhance the function of these organs. It is originally recorded with detoxicant effect on binge drink in Ben Cao Gang Mu Shi Yi, a persuasive Chinese materia medica. And binge dink has a close relationship with alcoholic liver disease (ALD). Hence, it's meaningful to investigate whether PJ exerts liver protection against binge drink toxicity.

AIM OF THE STUDY

This investigation was carried out not only to emphasize the right recognition of total saponins from PJ (SPJ), but also to study on its sober-up effectiveness and defensive mechanism against acute alcoholic liver injury in vivo and in vitro.

MATERIALS AND METHODS

SPJ constituents were verified by HPLC-UV analysis. In vivo, acute alcoholic liver oxidative stress and hepatosteatosis were established by continuous ethanol gavage to C57BL/6 mice for 3 days. SPJ was pre-administered for 7 days to investigate its protective efficacy. Loss of righting reflex (LORR) assay was employed to assess anti-inebriation effect of SPJ. Transaminases levels and hematoxylin and eosin (H&E) staining were measured to indicate the alcoholic liver injury. Antioxidant enzymes were measured to evaluate the oxidative stress degree in liver. Measurement of hepatic lipid accumulation was based on Oil Red O staining. Levels of inflammatory cytokines were evaluated by enzyme-linked immunosorbent assay (ELISA). In vitro, HepG2 cells were treated with ethanol for 24 h, and SPJ was pre-administered for 2 h. 2,7-dichlorofluorescein diacetate (DCFH-DA) was used as a probe to indicate reactive oxygen species (ROS) generation. Nrf2 activation was verified by the favor of specific inhibitor, ML385. The nuclear translocation of Nrf2 was indicated with immunofluorescence analysis. Proteins expressions of related pathways were determined by Western blotting.

RESULTS

Oleanane-type saponins are the most abundant constituents of SPJ. In this acute model, SPJ released inebriation of mice in a dose dependent manner. It decreased levels of serum ALT and AST, and hepatic TG. Besides, SPJ inhibited CYP2E1 expression and reduced MDA level in liver, with upregulations of antioxidant enzymes GSH, SOD and CAT. p62-related Nrf2 pathway was activated by SPJ with downstream upregulations of GCLC and NQO1 in liver. AMPK-ACC/PPARα axis was upregulated by SPJ to alleviate hepatic lipidosis. Hepatic IL-6 and TNF-α levels were downregulated by SPJ, which indicated a regressive lipid peroxidation in liver. In HepG2 cells, SPJ reduced ethanol-exposed ROS generation. Activated p62-related Nrf2 pathway was verified to contribute to the alleviation of alcohol-induced oxidative stress in hepatic cells.

CONCLUSION

This attenuation of hepatic oxidative stress and steatosis suggested the therapeutic value of SPJ for ALD.

Discovery of new quaternized norharmane dimers as potential anti-MRSA agents

INTRODUCTION

Methicillin-resistant Staphylococcus aureus (MRSA)-caused infections greatly threaten public health. The discovery of natural-product-based anti-MRSA agents for treating infectious diseases has become one of the current research focuses.

OBJECTIVES

This study aims to identify promising anti-MRSA agents with a clear mechanism based on natural norharmane modified by quaternization or dimerization.

METHODS

A total of 32 norharmane analogues were prepared and characterized. Their antibacterial activities and resistance development propensity were tested by the broth double-dilution method. Cell counting kit-8 and hemolysis experiments were used to assess their biosafety. The plasma stability, bactericidal mode, and biofilm disruption effects were examined by colony counting and crystal violet staining assays. Fluorescence microscopy, metabolomic analysis, docking simulation and spectra titration revealed its anti-MRSA mechanisms. The mouse skin infection model was used to investigate the in vivo efficacy.

RESULTS

Compound 5a was selected as a potential anti-MRSA agent, which exhibited potent anti-MRSA activity in vitro and in vivo, low cytotoxicity and hemolysis under an effective dose. Moreover, compound 5a showed good stability in 50% plasma, a low tendency of resistance development and capabilities to disrupt bacterial biofilms. The mechanism studies revealed that compound 5a could inhibit the biosynthesis of bacteria cell walls, damage the membrane, disturb energy metabolism and amino acid metabolism pathways, and interfere with protein synthesis and nucleic acid function.

CONCLUSIONS

These results suggested that compound 5a is a promising candidate for combating MRSA infections, providing valuable information for further exploiting a new generation of therapeutic antibiotics.

Click chemistry-based enrichment strategy for tracing cellular fatty acid metabolism by LC-MS/MS

Fatty acids (FAs), which were initially recognized as energy sources and essential building blocks of biomembranes, serve as the precursors of important signaling molecules. Tracing FA metabolism is essential to understanding the biochemical activity and role of FAs in physiological and pathological events. Inspired by the advances in click chemistry for protein enrichment, we herein established a click chemistry-based enrichment (CCBE) strategy for tracing the cellular metabolism of eicosapentaenoic acid (EPA, 20:5 n-3) in neural cells. Terminal alkyne-labeled EPA (EPAA) used as a surrogate was incubated with N2a, mouse neuroblastoma cells, and alkyne-labeled metabolites (ALMs) were selectively captured by an azide-modified resin via a Cu(I)-catalyzed azide-alkyne cycloaddition reaction for enrichment. After removing unlabeled metabolites, ALMs containing a triazole moiety were cleaved from solid-phase resins and subjected to liquid chromatography mass spectrometry (LC-MS) analysis. The proposed CCBE strategy is highly selective for capturing and enriching alkyne-labeled metabolites from the complicated matrices. In addition, this method can overcome current detection limits by enhancing MS sensitivity of targets, improving the chromatographic separation of sn-position glycerophospholipid regioisomers, facilitating structural characterization of ALMs by a specific MS/MS fragmentation signature, and providing versatile fluorescence detection of ALMs for cellular distribution. This CCBE strategy might be expanded to trace the metabolism of other FAs, small molecules, or drugs.

Ginsenoside Rk2, a dehydroprotopanaxadiol saponin, alleviates alcoholic liver disease via regulating NLRP3 and NLRP6 inflammasome signaling pathways in mice

Heavy alcohol consumption results in alcoholic liver disease (ALD) with inadequate therapeutic options. Here, we first report the potential beneficial effects of ginsenoside Rk2 (Rk2), a rare dehydroprotopanaxadiol saponin isolated from streamed ginseng, against alcoholic liver injury in mice. Chronic-plus-single-binge ethanol feeding caused severe liver injury, as manifested by significantly elevated serum aminotransferase levels, hepatic histological changes, increased lipid accumulation, oxidative stress, and inflammation in the liver. These deleterious effects were alleviated by the treatment with Rk2 (5 and 30 mg/kg). Acting as an nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3) inhibitor, Rk2 ameliorates alcohol-induced liver inflammation by inhibiting NLRP3 inflammasome signaling in the liver. Meanwhile, the treatment with Rk2 alleviated the alcohol-induced intestinal barrier dysfunction via enhancing NLRP6 inflammasome in the intestine. Our findings indicate that Rk2 is a promising agent for the prevention and treatment of ALD and other NLPR3-driven diseases.

Macromolecule-based hydrogels nanoarchitectonics with mesenchymal stem cells for regenerative medicine: A review

The role of regenerative medicine in clinical therapies is becoming increasingly vital. Under specific conditions, mesenchymal stem cells (MSCs) are capable of differentiating into mesoblastema (i.e., adipocytes, chondrocytes, and osteocytes) and other embryonic lineages. Their application in regenerative medicine has attracted a great deal of interest among researchers. To maximize the potential applications of MSCs, materials science could provide natural extracellular matrices and provide an effective means to understand the various mechanisms of differentiation for the growth of MSCs. Pharmaceutical fields are represented among the research on biomaterials by macromolecule-based hydrogel nanoarchitectonics. Various biomaterials have been used to prepare hydrogels with their unique chemical and physical properties to provide a controlled microenvironment for the culture of MSCs, laying the groundwork for future practical applications in regenerative medicine. This article currently describes and summarizes the sources, characteristics, and clinical trials of MSCs. In addition, it describes the differentiation of MSCs in various macromolecule-based hydrogel nanoarchitectonics and highlights the preclinical studies of MSCs-loaded hydrogel materials in regenerative medicine conducted over the past few years. Finally, the challenges and prospects of MSC-loaded hydrogels are discussed, and the future development of macromolecule-based hydrogel nanoarchitectonics is outlined by comparing the current literature.

Tissue-engineered edible bird’s nests (TeeBN)

Edible bird’s nests (EBN)—the nests of swiftlet birds harvested from the wild— are high-end healthcare food in East Asia, while their excessive harvesting poses increasing ecological, environmental, and food safety concerns. Here, we report for the first time a tissue-engineering (TE) approach for fabricating EBNs substitutes by integrating the technologies of three-dimensional (3D) printing and live cell culture. The engineered products, tissue-engineered edible bird’s nests (TeeBN), comprise two layers. The first is a feeding layer that encapsulates epithelial cells in 3D-printed biocompatible gelation scaffolds. These cells secrete bioactive ingredients, e.g., sialic acid and epidermal growth factors (EGF), recapitulating the natural production of these substances by birds. The second is a receiving layer, consisting of food-grade natural polymers, e.g., polysaccharides, which mimics the building blocks of natural EBNs while biologically stabilizing the factors released from the feeding layer. In vitro characterizations demonstrate that the feeding layer facilitates 3D cell growth and functions, and the receiving layer (as the end product) contains the necessary nutrients expected from natural EBNs—while without harmful substances commonly detected in natural EBNs. Further, in vivo metabolomics studies in mice indicate that TeeBN showed a similar profile of serum metabolites as natural EBN, reflecting comparable nutritional effects. In summary, we innovatively developed a tissue engineering-based substitute for EBNs with comparable metabolic functions and minimized safety risks, opening a new avenue for producing delicacy food from laboratorial cell culture with 3D printing technology. 

Biopolymer Food Packaging Films Incorporated with Essential Oils

Petroleum-based packaging materials are typically nonbiodegradable, which leads to significant adverse environmental and health issues. Therefore, developing novel efficient, biodegradable, and nontoxic food packaging film materials has attracted increasing attention from researchers. Due to significant research and advanced technology, synthetic additives in packaging materials are progressively replaced with natural substances such as essential oils (EOs). EOs demonstrate favorable antioxidant and antibacterial properties, which would be an economical and effective alternative to synthetic additives. This review summarized the possible antioxidant and antimicrobial mechanisms of various EOs. We analyzed the properties and performance of food packaging films based on various biopolymers incorporated with EOs. The progress in intelligent packaging materials has been discussed as a prospect of food packaging materials. Finally, the current challenges regarding the practical application of EOs-containing biopolymer films in food packaging and areas of future research have been summarized.

Biotransformation of the saponins in Panax notoginseng leaves mediated by gut microbiota from insomniac patients

Saponins extracted from Panax notoginseng leaves by methanol or water could be orally administrated for insomnia with very low bioavailability, which might be bio-converted by gut microbiota to generate potential bioactive products. Moreover, gut microbiota profiles from insomniac patients are very different from healthy subjects. We aimed to compare the metabolic characteristics and profiles of the two saponins extract by incubation with gut microbiota from insomniac patients. The ginsenosides, notoginsenosides, and metabolites were identified and relatively quantified by high-performance liquid chromatography-tandem mass spectrometry. Gut microbiota was profiled by 16S ribosomal RNA gene sequencing. The results showed that saponins were very different between methanol or water extract groups, which were metabolized by gut microbiota to generate similar yields. The main metabolites included ginsenoside Rd, ginsenoside F₂ , ginsenoside C-Mc or ginsenoside C-Y, ginsenoside C-Mx, ginsenoside compound K, and protopanaxadiol in both groups, while gypenoside XVII, notoginsenoside Fe, ginsenoside Rd₂ , and notoginsenoside Fd were the intermediates in the methanol group. Moreover, the microbial, Faecalibacterium prausnitzi, could bio-convert the saponins to obtain the corresponding metabolites. Our study implied that saponins extracted from P. notoginseng leaves by methanol or water could be used for insomniac patients due to gut microbiota biotransformation.

Chemical derivatization strategy for mass spectrometry-based lipidomics

Lipids, serving as the structural components of cellular membranes, energy storage, and signaling molecules, play the essential and multiple roles in biological functions of mammals. Mass spectrometry (MS) is widely accepted as the first choice for lipid analysis, offering good performance in sensitivity, accuracy, and structural characterization. However, the untargeted qualitative profiling and absolute quantitation of lipids are still challenged by great structural diversity and high structural similarity. In recent decade, chemical derivatization mainly targeting carboxyl group and carbon-carbon double bond of lipids have been developed for lipidomic analysis with diverse advantages: (i) offering more characteristic structural information; (ii) improving the analytical performance, including chromatographic separation and MS sensitivity; (iii) providing one-to-one chemical isotope labeling internal standards based on the isotope derivatization regent in quantitative analysis. Moreover, the chemical derivatization strategy has shown great potential in combination with ion mobility mass spectrometry and ambient mass spectrometry. Herein, we summarized the current states and advances in chemical derivatization-assisted MS techniques for lipidomic analysis, and their strengths and challenges are also given. In summary, the chemical derivatization-based lipidomic approach has become a promising and reliable technique for the analysis of lipidome in complex biological samples.

[Comparative study on short and long-term intervention impacts of six Chinese herbs with cold or heat property on lipid and energy metabolism in mice]

This study selected three typical Chinese herbs with cold property(Rhei Radix et Rhizoma, Scutellariae Radix, and Coptidis Rhizoma) and another three with heat property(Cinnamomi Cortex, Zingiberris Rhizoma, and Aconiti Lateralis Radix Praeparata) to observe their regulatory effects on metabolism in animal organism, especially on lipid and energy metabolism in mice after a short-(7 d) and long-term(35 d) intervention. The mRNA expression levels of lipid metabolism genes in epididymal adipose tissue and liver were determined by real-time PCR. The oxygen consumption, carbon dioxide production, and energy consumption were detected by metabolic system. After the short-term intervention, the Chinese herbs with heat property significantly reduced epididymal adipose tissue index and elevated the expression levels of acetyl-CoA carboxylase(ACC), lipoprotein lipase(LPL), and carnitine-palmityl transferase 1(CPT-1) in liver and epididymal adipose tissues. However, those with cold property promoted the expression of above-mentioned genes in epididymal adipose tissue. After the long-term intervention, cold and heat Chinese herbs had no significant effect on epididymal adipose tissue index of animals, while cold Chinese herbs could increase carbon dioxide production and energy consumption and reduce activity. These findings demonstrated that the short-term intervention effects of cold and heat Chinese herbs on animal metabolism were significantly stronger than the long-term intervention effects. Specifically, the short-term intervention with cold Chinese herbs enhanced the lipid metabolism in epididymal adipose tissue, while the heat Chinese herbs promoted lipid metabolism in epididymal adipose tissue and liver. The long-term intervention with cold and heat Chinese herbs resulted in no obvious change in lipid level, but long-term intervention with cold Chinese herbs accelerated energy consumption of the body. This study preliminarily observed the effects of cold and heat Chinese herbs on normal animal physiology from lipid and energy metabolism, which would provide reference for explaining the biological basis of Chinese herbs with cold or heat property based on biological response.

Chemical Stability of a Chinese Herbal Spirit Using LC-MS-Based Metabolomics and Accelerated Tests

As a prevalent medicinal liquor among Chinese people, a type of Chinese herbal spirit from Jing Brand Co., Ltd (CHS-J) is a newly developed health beverage with the health functions of anti-fatigue and immune enhancement. The researchers from the enterprise found that the contents of several components in CHS-J samples have been significantly decreasing during the stated storage period, as detected by the HPLC-UV method, which would make a great challenge for quality control of CHS-J. Furthermore, the chemical stability of CHS-J during the storage period is greatly challenged affected, especially in the environment of high temperature and light exposure. To systematically reveal the unstable components and promote the quality control of CHS-J, the chemical stability of CHS-J during the shelving storage period was characterized by the UPLC/Q-TOFMS-based metabolomics approach. First, the targeted and untargeted metabolomics approaches discovered the significantly changed components in CHS-J samples produced in different years. Furthermore, the accelerated tests of newly produced CHS samples and several authorized standards were conducted to validate the above results and elucidate the possible mechanisms underlying these chemical changes. Moreover, these chemical changes during the storage period had little influence on the anti-fatigue effect of CHS-J samples. These findings will offer new insight into the understanding of the chemical stability of CHS-J and will facilitate the quality control of CHS-J.

Integrating diverse plant bioactive ingredients with cyclodextrins to fabricate functional films for food application: a critical review

The popularity of plant bioactive ingredients has become increasingly apparent in the food industry. However, these plant bioactive ingredients have many deficiencies, including low water solubility, poor stability, and unacceptable odor. Cyclodextrins (CDs), as cyclic molecules, have been extensively studied as superb vehicles of plant bioactive ingredients. These CD inclusion compounds could be added into various film matrices to fabricate bioactive food packaging materials. Therefore, in the present review, we summarized the extraction methods of plant bioactive ingredients, the addition of these CD inclusion compounds into thin-film materials, and their applications in food packaging. Furthermore, the release model and mechanism of active film materials based on various plant bioactive ingredients with CDs were highlighted. Finally, the current challenges and new opportunities based on these film materials have been discussed.

Characterizing the influence of different drying methods on chemical components of Panax notoginseng leaves by heart-cutting two-dimensional liquid chromatography coupled to orbitrap high-resolution mass spectrometry

Panax notoginseng leaves (PNL) was considered as a promising functional food ingredient with abundant protopanaxdiol ginsenosides. In this study, the influence of different drying methods on chemical components in PNL was characterized by a newly developed heart-cutting 2D-LC-HRMS. Our data indicates that vigorous ginsenoside transformation occurs in PNL processed by sun-air drying and hot-air drying (HAD) at 50 °C, but not shade-air drying (SAD), HAD at 25 °C and steaming prior to drying (SD). Specifically, the main components of PNL, ginsenosides Rb3, Rc, Rb2, Rb1 and Rd, can be transformed into notoginsenosides Fd and Fe, ginsenoside Rd2, Gypenoside XVII and ginsenoside F2, respectively, by highly selective cleavage of β-1,2-glucosidic linkage at the C-3 position. Only SD can inactivate the proteins that mediate this transformation. Different drying methods also greatly affect the quality of PNL products extracted by the conventional decoction method. These findings offer the scientific basis to design industrial drying methods for ensuring the quality of PNL.

Red yeast rice ameliorates non-alcoholic fatty liver disease through inhibiting lipid synthesis and NF-κB/NLRP3 inflammasome-mediated hepatic inflammation in mice

BACKGROUND

Red yeast rice (RYR), a nutraceutical with a profound cholesterol-lowering effect, was found to attenuate non-alcoholic fatty liver disease (NAFLD) in mice. Despite monacolin K in RYR being a specific inhibitor of hydroxymethylglutaryl-coenzyme A reductase (HMCGR), the mechanisms underlying the protective effects of RYR against NAFLD are not fully elucidated.

METHODS

Using a mouse model of high-fat diet (HFD) feeding and a cellular model of HepG2 cells challenged by lipopolysaccharide (LPS) and palmitic acid (PA), the possible molecular mechanisms were exploited in the aspects of NF-κB/NLRP3 inflammasome and mTORC1-SREBPs signaling pathways by examining the relevant gene/protein expressions. Subsequently, the correlation between these two signals was also verified using cellular experiments.

RESULTS

RYR ameliorated lipid accumulation and hepatic inflammation in vivo and in vitro. RYR improved lipid metabolism through modulating mTORC1-SREBPs and their target genes related to triglyceride and cholesterol synthesis. Furthermore, RYR suppressed hepatic inflammation by inhibiting the NF-κB/NLRP3 inflammasome signaling. Interestingly, the treatment with RYR or MCC950, a specific NLRP3 inhibitor, resulted in the reduced lipid accumulation in HepG2 cells challenged by LPS plus PA, suggesting that the inhibitory effects of RYR on NLRP3 inflammasome-mediated hepatic inflammation may partially, in turn, contribute to the lipid-lowering effect of RYR.

CONCLUSIONS

The modulation of NF-κB/NLRP3 inflammasome and lipid synthesis may contribute to the ameliorative effects of RYR against HFD-induced NAFLD.

Natural and synthetic β-carboline as a privileged antifungal scaffolds

The discovery of antifungal agents with novel structure, broad-spectrum, low toxicity, and high efficiency has been the focus of medicinal chemists. Over the past decades, β-carboline scaffold has attracted extensive attention in the scientific community due to its potent and diverse biological activities with nine successfully marketed β-carboline-based drugs. In this review, we summarized the current states and advances in the antifungal activity of natural and synthetic β-carbolines. Additionally, the structure-activity relationships and their antifungal mechanisms targeting biofilm, cell wall, cell membrane, and fungal intracellular targets were also systematically discussed. In summary, β-carbolines have the great potential to develop new efficient scaffolds to combat fungal infections.

Cyclodextrin-Containing Hydrogels: A Review of Preparation Method, Drug Delivery, and Degradation Behavior

Hydrogels possess porous structures, which are widely applied in the field of materials and biomedicine. As a natural oligosaccharide, cyclodextrin (CD) has shown remarkable application prospects in the synthesis and utilization of hydrogels. CD can be incorporated into hydrogels to form chemically or physically cross-linked networks. Furthermore, the unique cavity structure of CD makes it an ideal vehicle for the delivery of active ingredients into target tissues. This review describes useful methods to prepare CD-containing hydrogels. In addition, the potential biomedical applications of CD-containing hydrogels are reviewed. The release and degradation process of CD-containing hydrogels under different conditions are discussed. Finally, the current challenges and future research directions on CD-containing hydrogels are presented.

Full Collision Energy Ramp-MS2 Spectrum in Structural Analysis Relying on MS/MS

Albeit frequently being overlooked, MS² spectrum variation against collision energy (CE) implies auxiliary structural clues for m/z values. Online energy-resolved MS (ER-MS) provides the opportunity to acquire the trajectory of ion intensity against CE for any fragment ion of interest, thus exactly offering the desired momentum to empower the conventional MS² spectrum at a certain CE forward to a full-CE ramp MS² spectrum (FCER-MS²). Efforts were made here to construct an FCER-MS² spectrum and to evaluate its potential toward structural analysis. Flavonoids were employed as a proof of concept. MS² spectra of 76 compounds were recorded by LC-Q-Exactive-MS, and online ER-MS was subsequently programmed using LC-Qtrap-MS to build a breakdown graph for each obvious fragment ion. After defining the greatest value amongst all regressive apices as 100%, the normalized breakdown graphs comprised an FCER-MS² spectrum for each compound. The FCER-MS² spectrum contained the MS² spectrum at any CE as well as optimal CE (OCE) and maximal relative ion intensity (RII_max) of each fragment ion. Except the pronounced isomeric discrimination potential, either OCE or RII_max reflected certain structural properties, such as aglycone, glycosidic bond, and hydroxy, methoxy, and glycosyl substituents. These rules were subsequently applied for flavonoid-focused characterization of a famous herbal medicine, namely Scutellariae Radix, and high-level structural annotation was accomplished for 75 flavonoids. Above all, the FCER-MS² spectrum includes m/z, OCEs, and RII_max features, thus facilitating confidence-advanced structural analysis.

Optical Imaging in the Second Near Infrared Window for Vascular Bioimaging

Optical imaging in the second near infrared region (NIR-II, 1000-1700 nm) provides higher resolution and deeper penetration depth for accurate and real-time vascular anatomy, blood dynamics, and function information, effectively contributing to the early diagnosis and curative effect assessment of vascular anomalies. Currently, NIR-II optical imaging demonstrates encouraging results including long-term monitoring of vascular injury and regeneration, real-time feedback of blood perfusion, tracking of lymphatic metastases, and imaging-guided surgery. This review summarizes the latest progresses of NIR-II optical imaging for angiography including fluorescence imaging, photoacoustic (PA) imaging, and optical coherence tomography (OCT). The development of current NIR-II fluorescence, PA, and OCT probes (i.e., single-walled carbon nanotubes, quantum dots, rare earth doped nanoparticles, noble metal-based nanostructures, organic dye-based probes, and semiconductor polymer nanoparticles), highlighting probe optimization regarding high brightness, longwave emission, and biocompatibility through chemical modification or nanotechnology, is first introduced. The application of NIR-II probes in angiography based on the classification of peripheral vascular, cerebrovascular, tumor vessel, and cardiovascular, is then reviewed. Major challenges and opportunities in the NIR-II optical imaging for vascular imaging are finally discussed.

Accurate quantification of endogenous N-acylethanolamides by chemical isotope labeling coupled with liquid chromatography-tandem mass spectrometry

N-acylethanolamides (NAEs) are a class of naturally occurring lipid molecules with pleiotropic activities ranging from energy homeostasis to analgesic functioning. However, the comprehensive quantitation of endogenous NAEs is challenged by the sub-trace level (nM) in complex biological samples and the limited availability of stable isotope labeled internal standards (SIL-IS). Herein, a sensitive method was developed to accurately determine 20 NAEs in biological samples by chemical isotope labeling strategy coupled with liquid chromatography - tandem mass spectrometry (LC-MS/MS). A pair of efficient derivatization reagents, acetyl chloride-d₀ (ACC-d₀) and acetyl chloride-d₃ (ACC-d₃), were used to label NAEs in biological samples and NAE standard mixture, respectively. The heavily labeled NAE derivatives of the standard substances were used as one-to-one internal standards to minimize the matrix effects and potential ion suppression in MS analysis. Although no chemical moiety with high ionization capability was introduced, the detection sensitivity of the derivatized NAEs were substantially enhanced, as evidenced by 6- to 170-fold increase in LOQs, compared to non-derivatized NAEs. The derivatized NAEs provided the stable and abundant specific product ions in MS/MS spectrum, which were used as the quantitation ions for multiple reaction monitoring (MRM) analysis. The validated LC-MS/MS method was also successfully applied to determine NAEs in serum samples and liver tissues from control and alcohol-fed mice, which shown its practicability in the analysis of endogenous NAE in biological samples. Collectively, the proposed method offers a sensitive and accurate quantification of endogenous NAEs, which may facilitate the understanding of NAE metabolisms and their functions in the physiological and pathological processes.

A bioactive ligand-conjugated iridium(III) metal-based complex as a Keap1-Nrf2 protein-protein interaction inhibitor against acetaminophen-induced acute liver injury

Hepatotoxicity caused by an overdose of acetaminophen (APAP) is the leading reason for acute drug-related liver failure. Nuclear factor erythroid-2-related factor 2 (Nrf2) is a protein that helps to regulate redox homeostasis and coordinate stress responses via binding to the Kelch-like ECH-associated protein 1 (Keap1). Targeting the Keap1-Nrf2 interaction has recently emerged as a potential strategy to alleviate liver injury caused by APAP. Here, we designed and synthesized a number of iridium (III) and rhodium (III) complexes bearing ligands with reported activity against oxidative stress, which is associated with Nrf2 transcriptional activation. The iridium (III) complex 1 bearing a bioactive ligand 2,9-dimethyl-1,10-phenanthroline and 4-chloro-2-phenylquinoline, a derivative of the bioactive ligand 2-phenylquinoline, was identified as a direct small-molecule inhibitor of the Keap1–Nrf2 protein-protein interaction. 1 could stabilize Keap1 protein, upregulate HO-1 and NQO1, and promote Nrf2 nuclear translocation in normal liver cells. Moreover, 1 reversed APAP-induced liver damage by disrupting Keap1–Nrf2 interaction and without inducing organ damage and immunotoxicity in mice. Our study demonstrates the identification of a selective and efficacious antagonist of Keap1–Nrf2 interaction possessed good cellular permeability in cellulo and ideal pharmacokinetic parameters in vivo, and, more importantly, validates the feasibility of conjugating metal complexes with bioactive ligands to generate metal-based drug leads as non-toxic Keap1–Nrf2 interaction inhibitors for treating APAP-induced acute liver injury.

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1 reversed APAP-induced liver damage by disrupting Keap1–Nrf2 interaction without inducing organ damage or immunotoxicity.

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Complex 1 possessed good cellular permeability in cellulo and ideal pharmacokinetic parameters in vivo.

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Conjugating metal complexes with bioactive ligands opens a novel avenue for the treatment of APAP-induced liver damage.

Preparative separation of gypenoside XVII, ginsenoside Rd2, and notoginsenosides Fe and Fd from Panax notoginseng leaves by countercurrent chromatography and orthogonality evaluation for their separation

The minor ginsenosides with less polarity may have more potent biological activities. Four minor saponins, i.e., gypenoside XVII, ginsenoside Rd2, notoginsenoside Fe, and notoginsenoside Fd, were successfully separated from Panax notoginseng leaves (PNL) after biotransformation by one-step countercurrent chromatography using the biphasic solvent system consisting of n-butanol-ethyl acetate-water (1:4:5, v/v/v). 30 mg of the refined extract of PNL produced 1 mg of gypenoside XVII, 4 mg of notoginsenoside Fe, 2.5 mg of ginsenoside Rd2, and 8.4 mg of notoginsenoside Fd, with purity of 74.9, 95.2, 87.3, and 97.6%, respectively. Besides, orthogonality evaluation for the separation of the four saponins using countercurrent chromatography and liquid chromatography was discussed. Four minor saponins were successfully separated from each other on a preparative scale by countercurrent chromatography from PNL, which will facilitate to provide ample of these minor saponins for further pharmacological studies.

Ginsenoside distribution in different architectural components of Panax notoginseng inflorescence and infructescence

The roots of Panax notoginseng (Burk) F. H. Chen are used as a highly valuable Chinese herbal medicine in the prevention and treatment of cardiovascular and hematological diseases. Several aerial parts of plant are usually abandoned as the wastes. Panax notoginseng inflorescence (IFO) is commonly used as a folk medicine and dietary ingredient, its fruiting stage is referred as infructescence (IFU). Owing to high chemical complexity and structural similarity of ginsenosides, the co-eluting phenomenon, especially for the isomers, is inevitable in the chromatogram, resulting in the inaccurate quantitation. A novel LCMS method using hybrid positive full scan and multiple reaction monitoring (MRM) modes was developed to characterize ginsenoside distribution in different architectural components of IFO and IFU. MRM was performed for the quantification of G-Ra2 and NG-Fp2, a pair of co-eluting isomers with identical negative MS and MS/MS characteristics, and full scan was conducted to quantify other investigated saponins. Our data indicate that flower buds have the highest abundance of the summed saponins, fruit pedicel and fruit pericarp, commonly considered as the useless by-products of seed processing, contain the abundant saponins. Additionally, the contents of the detected ginsenosides in these architectural components significantly increased along with their growth years. Our findings will facilitate comprehensive utilization and exploitation of P. notoginseng inflorescence and infructescence.

Quantitative analysis of n-3 polyunsaturated fatty acids and their metabolites by chemical isotope labeling coupled with liquid chromatography - mass spectrometry

n-3 polyunsaturated fatty acids (PUFAs) and their metabolites play the crucial role in a wide range of physiologic and pathologic processes, including cardiovascular, neurodegenerative diseases, and inflammation-associated disorders. However, the quantitative analysis of n-3 PUFAs and their metabolites, oxylipins, is obstructed by high structural similarity, poor ionization efficiency and low abundance. In this study, a sensitive method was developed to quantify 28 n-3 PUFAs/oxylipins using chemical isotope labeling coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS). Standards labeled with cholamine-d₉ were used as one-to-one internal standards to achieve accurate quantification. The cholamine-d₀-derivatized biological samples were mixed with cholamine d₉-labeled standards for LC-MS/MS with multiple reaction monitoring. After cholamine derivatization, both MS sensitivity and chromatographic performance of n-3 PUFAs/oxylipins were substantially improved. Furthermore, the relationship between retention time and substituent position of regioisomers, and their fragmentation patterns were investigated, which may facilitate the identification of unknown oxylipins. Additionally, the developed method was applied to quantify the target n-3 PUFAs/oxylipins in serum and brain tissue from fish oil-supplemented mice, which exhibited its great potential and practicability. Collectively, this sensitive and reliable method may facilitate the elucidation of the roles of n-3 PUFAs/oxylipins in the physiological and pathological processes.

A four-component combination derived from Huang-Qin Decoction significantly enhances anticancer activity of irinotecan

Huang-Qin Decoction (HQD) is a classic prescription for diarrhea in Chinese medicine treatment. Recent studies have demonstrated that HQD and its modified formulation PHY906 could ameliorate irinotecan (CPT-11) induced gastrointestinal (GI) toxicity and enhance its anticancer therapeutic efficacy. Nevertheless, which constituents in HQD are effective is still unclear so far. The study aims to screen out the key bioactive components combination from HQD that could enhance the anticancer effect of CPT-11. First, the potential bioactive constituents were obtained through system pharmacology strategy. Then the bioactivity of each constituent was investigated synthetically from the aspects of NCM460 cell migration, TNF-α release of THP-1-derived macrophage and MTT assay in HCT116 cell. The contribution of each constituent in HQD was evaluated using the bioactive index E_i, which taken the content and bioactivity into comprehensive consideration. And then, the most contributing constituents were selected out to form a key-component combination. At last, the bioefficacy of the key-component combination was validated in vitro and in vivo. As a result, a key-component combination (HB4) consisting of four compounds baicalin, baicalein, glycyrrhizic acid and wogonin was screened out. In vitro assessment indicated that HB4 could enhance the effect of CPT-11 on inhibiting cell proliferation and inducing apoptosis in HCT116. Furthermore, the in vivo study confirmed that HB4 and HQD have similar pharmacological activity and could both enhance the antitumor effect of CPT-11 in HCT116 xenograft model. Meanwhile, HB4 could also reduce the CPT-11 induced GI toxicity.

Simultaneous quantification of bioactive components in Chinese herbal spirits by ultra-high performance liquid chromatography coupled to triple-quadrupole mass spectrometry (UHPLC-QQQ-MS/MS)

BACKGROUND

The Chinese medicinal wine made from herbal medicines became prevalent among Chinese people. The Chinese herbal spirit is composed of several herbal extracts, and has the certain health functions, such as anti-fatigue and immune regulation. The quality evaluation of Chinese herbal spirit is greatly challenged by the enormous and complex components with great structural diversity and wide range of concentration distribution.

METHODS

An ultra-high performance liquid chromatography coupled to triple quadrupole mass spectrometry (UHPLC-QQQ-MS/MS) with multiple reaction monitoring (MRM) method was developed to simultaneously determine forty-three bioactive components in the Chinese herbal spirits produced by year 2014 and 2018.

RESULTS

Quantitative results showed that 11 components, i.e.., puerarin (5), purpureaside C (7), daidzin (8), echinacoside (9), acteoside (15), epimedin B (22), epimedin C (23), icariin (24), eugenol (27), chikusetsusaponin iva (30) and Z-ligustilide (40), significantly decreased along with the increasing years of storage, while 5 compounds, i.e.., geniposidic acid (1), protocatechuic acid (2), crustecdysone (14), daidzein (18) and icariside I (35), were basically stable in all samples across the years.

CONCUSION

The established method allowing to simultaneously determined 43 components with wide structural diversity and trace amounts will facilitate the quality control research of Chinese herbal spirits.

Ginsenosides Rb2 and Rd2 isolated from Panax notoginseng flowers attenuate platelet function through P2Y12-mediated cAMP/PKA and PI3K/Akt/Erk1/2 signaling

Saponins derived from Panax notoginseng root are widely used as herbal medicines and dietary supplements due to their wide range of health benefits. However, the effects of those from Panax notoginseng flowers (PNF) on platelet function and thrombus formation remain largely unknown. Using a series of platelet function assays, we found that G-Rb2 and G-Rd2, among the ten PNF saponin monomers, significantly inhibited human platelet aggregation and activation induced by adenosine diphosphate (ADP) in vitro. The 50% inhibitory concentration (IC50) of G-Rb2 and G-Rd2 against ADP-induced platelet aggregation was 85.5 ± 4.5 μg mL-1 and 51.4 ± 4.6 μg mL-1, respectively. Mechanistically, G-Rb2 and G-Rd2 could effectively modulate platelet P2Y12-mediated signaling by up-regulating cAMP/PKA signaling and down-regulating PI3K/Akt/Erk1/2 signaling pathways. Co-incubation of the P2Y12 antagonist cangrelor with either G-Rb2 or G-Rd2 did not show significant additive inhibitory effects. G-Rb2 and G-Rd2 also substantially suppressed thrombus growth in a FeCl3-induced murine arteriole thrombosis model in vivo. Interestingly, G-Rd2 generally exhibited more potent inhibitory effects on platelet function and thrombus formation than G-Rb2. Thus, our data suggest that PNF-derived G-Rb2 and G-Rd2 effectively attenuate platelet hyperactivity through modulating signaling pathways downstream of P2Y12, which indicates G-Rb2 and G-Rd2 may play important preventive roles in thrombotic diseases.

Regulation of the NLRP3 inflammasome with natural products against chemical-induced liver injury

The past decades have witnessed significant progress in understanding the process of sterile inflammation, which is dependent on a cytosolic complex termed the nucleotide-binding oligomerization domain (NOD)-like receptor containing pyrin domain 3 (NLRP3) inflammasome. Activation of NLRP3 inflammasome requires two steps, including the activation of Toll-like receptor (TLR) by its ligands, resulting in transcriptional procytokine and inflammasome component activation, and the assembly and activation of NLRP3 inflammasome triggered by various danger signals, leading to caspase-1 activation, which could subsequently cleave procytokines into their active forms. Metabolic disorders, ischemia and reperfusion, viral infection and chemical insults are common pathogenic factors of liver-related diseases that usually cause tissue damage and cell death, providing numerous danger signals for the activation of NLRP3 inflammasome. Currently, natural products have attracted much attention as potential agents for the prevention and treatment of liver diseases due to their multitargets and nontoxic natures. A great number of natural products have been shown to exhibit beneficial effects on liver injury induced by various chemicals through regulating NLRP3 inflammasome pathways. In this review, the roles of the NLRP3 inflammasome in chemical-induced liver injury (CILI) and natural products that exhibit beneficial effects in CILI through the regulation of inflammasomes were systematically summarized.

Fish oil alleviates LPS-induced inflammation and depressive-like behavior in mice via restoration of metabolic impairments

Our previous study revealed that fish oil (FO) pre-treatment could improve the lipopolysaccharides (LPS)-induced depressive-like behavior in mice but did not alter the expression of stress hormones associated with the hypothalamic-pituitary-adrenal (HPA) axis. The exact mechanisms underlying the protective effects of FO remain elusive. Here we applied the metabolomic technique to investigate the potential involvement of FO metabolites in ameliorating depressive-like behaviors in LPS-injected mice. It revealed that LPS-injection stimulated systemic inflammation, exhausted the nicotinamide adenine dinucleotide (NAD) level in the brain, decreased energy metabolism and impaired neuronal function, which collectively contributed to depressive-like behaviors in mice. FO treatment enhanced the production of neuroprotective metabolites including taurine, hypotaurine and tyramine, decreased the generation of neurotoxic agents such as ADPR, glutamate accumulation and oxidized glutathione, and prevented the NAD exhaustion in the brain, which might underlie the beneficial effects of FO against LPS-induced inflammation and depressive-like behaviors.

Synergistic anti-breast cancer effect of pulsatilla saponin D and camptothecin through interrupting autophagic-lysosomal function and promoting p62-mediated ubiquitinated protein aggregation

Autophagy is an evolutionarily conserved mechanism to protect the cells from unfavorable environmental conditions. Inhibition of autophagy has been contemplated as a novel strategy to enhance anticancer efficacy of existing chemotherapeutic agents. We previously reported that pulsatilla saponin D (PSD) was a potent autophagy inhibitor. However, its anticancer potential as adjuvant and underlying mechanisms are still unknown. In this study, we identified that PSD induced the formation of autophagosome in MCF-7 and MDA-MB-231 breast cancer cells. However, PSD alone and particularly co-treatment with camptothecin remarkably increased p62 protein levels, indicating that PSD strongly inhibited the autophagic cargo degradation. The mechanistic study indicated that PSD profoundly abolished the co-localization of EGFP-LC3 and lysosomal-specific probe LysoTracker Red, suggesting that the autophagosome-lysosome fusion was blocked by PSD, which is similar to the action of chloroquine. In addition, PSD significantly increased lysosomal pH and inhibited the activation of lysosomal cathepsins in both breast cancer cell lines. Furthermore, the accrued p62 resulted in accumulation of ubiquitinated proteins owing to the interaction with p62 and delivery to the malfunctioned autophagosome by PSD. Finally, we demonstrated that PSD synergistically enhanced the anticancer activity of camptothecin (CPT) in cultured breast cancer cells and in mouse xenograft tumor models. Our results indicated that PSD inhibited autophagic flux via blocking autophagosome-lysosome fusion and lysosomal acidification, which may confer a synergistic anti-breast cancer activity of PSD and CPT.

Oxidation of fish oil exacerbates alcoholic liver disease by enhancing intestinal dysbiosis in mice

The role of n-3 polyunsaturated fatty acids (PUFAs) in alcoholic liver disease (ALD) has been controversial. N-3 PUFA oxidation in animal feeding stuffs was rarely concerned, likely contributing to inconsistent outcomes. Here, we report the impacts of oxidized fish oil (OFO) on ALD in C57BL/6 mice. Alcohol exposure increased plasma aminotransferase levels and hepatic inflammation. These deleterious effects were ameliorated by unoxidized FO but exacerbated by OFO. Sequencing analysis showed the accentuated intestinal dysbiosis and the increased proportion of Proteobacteria in OFO-fed mice. Intestinal sterilization by antibiotics completely abolished OFO-aggravated liver injury. Additionally, alcohol exposure leads to the greater increase in plasma endotoxin and decrease in intestinal tight junction protein expressions in OFO-fed mice. Stabilization of intestinal barrier by obeticholic acid markedly blunted OFO-aggravated liver injury in alcohol-fed mice. These results demonstrate that OFO exacerbates alcoholic liver injury through enhancing intestinal dysbiosis, barrier dysfunction, and hepatic inflammation mediated by gut-derived endotoxin.

Feng et al. show that oxidized fish oil exacerbates alcoholic liver injury in mice by enhancing intestinal dysbiosis, barrier dysfunction, and hepatic inflammation that is mediated by gut-derived endotoxin. This study suggests that n-3 polyunsaturated fatty acids enriched in fish oil should be kept from oxidation to exert their health benefits.

Characterization of the cold and hot natures of raw and processed Rehmanniae Radix by integrated metabolomics and network pharmacology

BACKGROUND

The processing of Chinese materia medica (CMM) is one of the characteristics and advantages of traditional Chinese medicine (TCM). Occasionally, the processing of CMM might reverse the cold/hot nature of CMM. For example, the nature of raw Rehmanniae Radix (RR) is cool, while the processed Rehmanniae Radix (PR) by steaming is hot. Because the cold/hot nature of CMM is defined by the body's response to CMMs, a metabolomics approach, allowing the monitoring of the fluctuation of endogenous metabolites related to an exogenous stimulus, might be an ideal tool to uncover the cold/hot nature of different forms of Rehmanniae Radix.

PURPOSE

An integrated strategy combining metabolomics and network pharmacology was applied to illuminate the different natures of raw and processed Rehmanniae Radix.

STUDY DESIGN

Mice were orally administered RR and PR once daily for ten days. The entire metabolic changes in the plasma of mice were profiled by ultra-high performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UHPLC/Q-TOF MS). Furthermore, network pharmacology analysis was performed to identify the underlying targets related to iridoids that significantly changed during the processing.

RESULTS

The metabolomics analysis results demonstrated a clear separation of the metabolic phenotypes among the control, RR and two PR groups in both the positive and negative modes. Nine lysophosphatidylcholines (LysoPCs), LysoPC (16:0), LysoPC (18:2), LysoPC (18:1), LysoPC (22:6), LysoPC (20:2), LysoPC (18:0), LysoPC (16:1), LysoPC (20:4) and LysoPC (20:5), that decreased in the RR-treated group, but increased in the PR-treated group, were identified to be potential biomarkers related to the natures of RR and PR. The network pharmacology results indicated that four iridoids in Rehmanniae Radix, 8-epiloganic acid, 6-O-p-coumaroyl ajugol, 6-O-p-hydroxybenzoyl ajugol and ajugol, might play important roles in the different natures of raw and processed Rehmanniae Radix.

CONCLUSIONS

There might be a strong connection between the cold/hot nature of different forms of Rehmanniae Radix and LysoPC metabolism. This study offers new insight into the cold/hot nature of Rehmanniae Radix.

Quantitative Characterization of Ginsenoside Biotransformation in Panax notoginseng Inflorescences and Leaves by Online Two-Dimensional Liquid Chromatography Coupled to Mass Spectrometry

Panax notoginseng inflorescences (PNI) and leaves (PNL) are commonly used as folk medicine and food supplements. In this study, an online two-dimensional hydrophilic interaction × reversed-phase liquid chromatography coupled to linear trap quadropole mass spectrometry method was developed to determine 24 ginsenosides, including two novel compounds, in PNI and PNL extracted by water and methanol. Our data demonstrated that ginsenosides Rd, Rc, Rb2, Rb3, Rb1, Ra2, Ra1, and Ra3 in both PNI and PNL extracted by water rather than methanol can be transformed to ginsenoside F2, notoginsenoside Fe, ginsenoside Rd2, notoginsenoside Fd, gypenoside XVII, PN02, PN01, and PN03, respectively, by selectively cleaving the β-(1→2)-glucosidic linkage at the C-3 position. Ginsenoside transformation was further verified to be mediated by the proteins isolated from samples. Additionally, the two newly discovered transformed products, namely, PN02 and PN03, were prepared and identified as novel compounds by nuclear magnetic resonance. Our findings provide new insight into the importance of extraction solvents on the component profile of natural products.

LC-MS-based multivariate statistical analysis for the screening of potential thrombin/factor Xa inhibitors from Radix Salvia Miltiorrhiza

Background

The dry root and rhizome of Salvia miltiorrhiza Bunge, or Danshen, is a well-known traditional Chinese medicine with anticoagulant activity. Taking into account that thrombin (THR) and factor Xa (FXa) play crucial roles in the coagulation cascade, it is reasonable and meaningful to screening THR and/or FXa inhibitors from Danshen.

Methods

Four extracts [butanol (BA), ethyl acetate (EA) and remained extract (RE) from 75% ethanol extract, and water extract (WE)] of Danshen were prepared, and their THR/FXa inhibitory activities were assessed in vitro. Then, the active EA extract was further separated by silica-gel column chromatography (SC), and its fractions (SC1–SC5) were analyzed by LC–MS. The principal component analysis (PCA) and orthogonal partial least squares discriminate analysis (OPLS-DA) were employed for predicting the specific marker compounds. The chemical structures of targeted compounds were identified by LC–MS/MS and their interactions with THR/FXa were analyzed by the molecular docking analysis.

Results

Danshen EA extract showed strong activity against THR and FXa, and its fractions (SC1–SC5) exhibited obvious difference in inhibitory activity against these two enzymes. Furthermore, four marker compounds with potential THR/FXa inhibitory activity were screened by PCA and OPLS-DA, and were identified as cryptotanshinone, tanshinone I, dihydrotanshinone I and tanshinone IIA. The molecular docking study showed that all these four tanshinones can interact with some key amino acid residues of the THR/FXa active cavities, such as HIS57 and SER195, which were considered to be promising candidates targeting THR and/or FXa with low binding energy (< − 7 kcal mol⁻¹).

Conclusions

LC–MS combined with multivariate statistical analysis can effectively screen potential THR/FXa inhibitory components in Danshen.

Targeted bile acids and gut microbiome profiles reveal the hepato-protective effect of WZ tablet (Schisandra sphenanthera extract) against LCA-induced cholestasis

Cholestasis is caused by the obstacle of bile formation or secretion and can develop into severe liver diseases. We previously reported the ethanol extract of Schisandra sphenanthera (Wuzhi tablet, WZ) can significantly protect against lithocholic acid (LCA)-induced intrahepatic cholestasis in mice, partially due to the activation of PXR pathway and promotion of liver regeneration. However, the effect of WZ on the bile acids profile and gut microbiome in cholestastic mice remain unknown. In this study, the effect of WZ against LCA-induced liver injury was evaluated and its effect on the bile acids metabolome and gut microbiome profiles in cholestastic mice was further investigated. Targeted metabolomics analysis was performed to examine the change of bile acids in the serum, liver, intestine and feces. The change of intestinal flora were detected by the genomics method. Targeted metabolomics analysis revealed that WZ enhanced the excretion of bile acids from serum and liver to intestine and feces. Genomics analysis of gut microbiome showed that WZ can reverse LCA-induced gut microbiome disorder to the normal level. In conclusion, WZ protects against LCA-induced cholestastic liver injury by reversing abnormal bile acids profiles and alteration of gut microbiome.

Fish oil protects the blood-brain barrier integrity in a mouse model of Alzheimer's disease

BACKGROUND

Alzheimer's disease (AD) is ranked as the most prevalent neurodegenerative disease. However, the exact molecular mechanisms underlying pathophysiological alterations in AD remain unclear, especially at the prodromal stage. The decreased proteolytic degradation of Aβ, blood-brain barrier (BBB) disruption, and neuroinflammation are considered to play key roles in the course of AD.

METHODS

Male APPswe/PS1dE9 C57BL/6 J double-transgenic (APP/PS1) mice in the age range from 1 month to 6 months and age-matched wild type mice were used in this study, intending to investigate the expression profiles of Aβ-degrading enzymes for Aβ degradation activities and zonula occludens-1 (zo-1) for BBB integrity at the prodromal stage.

RESULTS

Our results showed that there were no significant genotype-related alterations in mRNA expression levels of 4 well-characterized Aβ-degrading enzymes in APP/PS1 mice within the ages of 6 months. Interestingly, a significant decrease in zo-1 expression was observed in APP/PS1 mice starting from the age of 5 months, suggesting that BBB disrupt occurs at an early stage. Moreover, treatment of fish oil (FO) for 4 weeks remarkably increased zo-1 expression and significantly inhibited the glial activation and NF-κB activation in APP/PS1 mice.

CONCLUSION

The results of our study suggest that FO supplement could be a potential therapeutic early intervention for AD through protecting the BBB integrity and suppressing glial and NF-κB activation.

Omega-3 polyunsaturated fatty acids promote brain-to-blood clearance of β-Amyloid in a mouse model with Alzheimer's disease

Amyloid-β (Aβ) plaques is one of the typical pathological hallmark of Alzheimer disease (AD). Accumulating evidence suggests that the imbalance between Aβ production and clearance leads to extracellular Aβ accumulation in the brain. It is reported that the blood-brain barrier (BBB) transport plays a predominant role in Aβ clearance from brain to blood. In the present study, we investigated dynamic alterations of BBB transport function in the early disease stage of AD using APPswe/PS1dE9 C57BL/6J (APP/PS1) transgenic mice. Our results showed that the expression of lipoprotein receptor-related protein 1 (LRP-1), a main efflux transporter of BBB, started to decrease at the age of 4 months old. Interestingly, supplementing with fish oil which is rich in omega-3 polyunsaturated fatty acids (PUFAs) significantly enhanced the expression level of LRP-1 and promoted Aβ clearance from the bran to circulation, as revealed by reduced soluble/insoluble Aβ levels and senile plaques in the brain parenchyma and a corresponding increase of Aβ levels in plasma. Besides, fish oil supplement significantly inhibited the NF-κB activation, reduced the expression of interleukin-1β and tumor necrosis factor-α, and suppressed the glial activation in APP/PS1 mice. The results of the study provide evidence that BBB transport function could be impaired at a very early disease stage, which might contribute to Aβ pathological accumulation in AD, and omega-3 PUFAs intervention could be an effective strategy for the prevention of the progression of AD through promoting Aβ clearance from brain-to-blood.

Metabolomics study of the anti-inflammatory effects of endogenous omega-3 polyunsaturated fatty acids

Low-grade inflammation is usually defined as the chronic production and a low-grade state of inflammatory factors, it often does not have symptoms, and has been associated with neurodegenerative disease, obesity, and diabetes. Omega-3 polyunsaturated fatty acids (n-3 PUFAs) are the precursors of many anti-inflammatory metabolites, such as resolvins and neuroprotectins. It is of interest to study the metabolic profile of endogenous n-3 PUFAs in low-grade inflammatory conditions. To evaluate the protective effects of endogenous n-3 PUFAs on low-grade inflammation with the metabolomics approach, we fed fat-1 mice with an n-6 PUFAs rich diet for a long time to induce a low-grade inflammatory condition. Multi-analysis techniques, including structural analysis using quadrupole time-of-flight mass spectrometry with MS^E mode, were applied in untargeted metabolomics to search for meaningful metabolites with significant variance in fat-1 mice under low-grade inflammation. Following the untargeted metabolomics screening, several meaningful metabolites were selected which were associated with anti-inflammatory effects generated from endogenous n-3 PUFAs for further analysis. The results revealed that the purine metabolism, fatty acid metabolism and oxidative stress response pathways through insulin resistance were involved in anti-inflammatory mechanisms of n-3 PUFA in low-grade inflammatory conditions. For the first time, this study explored the highlighted pathways as contributors to the anti-inflammatory effects of endogenous n-3 PUFAs in low-grade inflammatory conditions.

Low-grade inflammation is usually defined as the chronic production and a low-grade state of inflammatory factors, it often does not have symptoms, and has been associated with neurodegenerative disease, obesity, and diabetes.

Glycine tabacina ethanol extract ameliorates collagen-induced arthritis in rats via inhibiting pro-inflammatory cytokines and oxidation

ETHNOPHARMACOLOGICAL RELEVANCE

The whole plant of Glycine tabacina (Labill.) Benth has been used as a traditional herbal medicine to treat rheumatism, ostealgia and nephritis in China. It is also one of the sources of the renowned native herbal medicine 'I-Tiao-Gung' in Taiwan.

AIM OF THE STUDY

This study aimed to investigate the anti-arthritic effect of ethanol extract of G. tabacina (GTE) in a collagen-induced arthritis (CIA) rat model.

MATERIALS AND METHODS

The chemical profile of GTE was analyzed by HPLC-UV. The CIA was induced in male Wistar rats by intradermal injection of bovine type II collagen at tail root, back and ankle joints. The rats were orally administrated daily with GTE (1.11, 2.22 and 4.44 g dry weight of herb powder per kg body weight) from day 0 and continued for 30 days. Swelling volume and thickness of paw, arthritis index, X-radiographs and histopathological changes were examined to assess the severity of arthritis. Furthermore, the levels of pro-inflammatory cytokines, such as interleukin1β (IL-1β), IL-6 and tumor necrosis factor α (TNF-α), total superoxide dismutase (T-SOD) activity and malonaldehyde (MDA) level were measured to preliminarily explore the possible mechanisms.

RESULTS

Oral administration of GTE significantly ameliorated the arthritic symptoms in CIA rat model, as indicated by the effects on paws swelling and arthritis index. X-radiographic analysis and histopathological examinations demonstrated that GTE effectively protected the bone and cartilage of joints from erosion, lesion and deformation. The efficacy of GTE treatment on CIA was comparable to that of indomethacin (positive drug). Besides, the overproduction of IL-1β, IL-6 and TNF-α was remarkably inhibited in the serum of all GTE treatment groups. The restoration of serum T-SOD activity and MDA level proved that GTE administration alleviated the oxidative stress in CIA rats.

CONCLUSIONS

GTE exhibited strong anti-CIA activity through inhibiting pro-inflammatory cytokines and oxidation in rats, suggesting its potential preventive and therapeutic effects on rheumatoid arthritis (RA).

CuS Nanoparticles as a Photodynamic Nanoswitch for Abrogating Bypass Signaling To Overcome Gefitinib Resistance

Bypass signaling activation plays a crucial role in the acquired resistance of gefitinib, the first targeted drug in the clinic to treat advanced non-small cell lung cancer. Although the inactivation of bypass signaling by small-molecule inhibitors or monoclonal antibodies may overcome gefitinib resistance, their clinical use has been limited by the complex production process and off-target toxicity. Here we show CuS nanoparticles (NPs) behaved as a photodynamic nanoswitch to specifically abrogate overactive bypass signaling in resistant tumor cells without interfering with the same signal pathways in normal cells. In representative insulin growth factor-1 receptor (IGF1R) bypass activation-induced gefitinib resistant tumors, CuS NPs upon near-infrared laser irradiation locally elevated reactive oxygen species (ROS) level in tumor cells, leading to the blockage of bypass IGF1R and its downstream AKT/ERK/NF-κB signaling cascades. Consequently, laser-irradiated CuS NPs sensitized tumors to gefitinib treatment and prolonged the survival of mice with no obvious toxicity. Laser-irradiated CuS NPs may serve as a simple and safe nanomedicine strategy to overcome bypass activation-induced gefitinib resistance in a specific and controllable manner and provide insights into the treatment of a myriad of other resistant tumors in the field of cancer therapy.

A combination of Pueraria lobata and Silybum marianum protects against alcoholic liver disease in mice

BACKGROUND

Excess alcohol exposure leads to alcoholic liver disease (ALD). Pueraria lobata (PUE) and Silybum marianum (SIL) are two well-known hepatoprotective herbal remedies with various activities. The possible effect of combination of PUE and SIL on ALD has not been elucidated yet.

PURPOSE

We aimed to demonstrate that the combination of PUE and SIL prevents against alcoholic liver injury in mice using a model of chronic-plus-single-binge ethanol feeding.

STUDY DESIGN

Male C57BL/6 mice were randomly divided into five groups (n = 8-10), namely the control group (CON), ethanol-induced liver injury group (ETH), 150 mg/kg PUE treated group (PUE), 60 mg/kg SIL treated group (SIL), 210 mg/kg PUE+SIL treatment group (PUE+SIL). Except control group, all animals were fed a modified Lieber-DeCarli ethanol liquid diet for 10 days. While, control group received Lieber-DeCarli control diet containing isocaloric maltose dextrin substituted for ethanol. On day 11, the mice orally received a single dose of 31.5% (v/v) ethanol (5 g/kg BW) or an isocaloric maltose solution.

RESULTS

Ethanol exposure caused liver injury, as demonstrated by remarkably increased plasma parameters, histopathological changes, the increased lipid accumulation, oxidative stress and inflammation in liver. These alterations were ameliorated by the treatments of PUE, SIL and PUE+SIL. While, the PUE+SIL treatment showed the most effective protection, which was associated with reducing alcohol-induced hepatic steatosis via upregulating LKB1/AMPK/ACC signaling, and inhibiting hepatic inflammation via LPS-triggered TLR4-mediated NF-κB signaling pathway. Our results also indicated that the hepatoprotective effects of SIL+PUE might mainly attribute to the protection of SIL and PUE alone in alcohol-induced hepatic steatosis and hepatic inflammation, respectively.

CONCLUSION

These findings also suggest that the combination of PUE and SIL has a potential to be developed as a functional food for the management of ALD.

Aurone derivatives as Vps34 inhibitors that modulate autophagy

We report in this study the identification of a natural product-like antagonist (1a) of Vps34 as a potent autophagy modulator via structure-based virtual screening. Aurone derivative 1a strongly inhibited Vps34 activity in cell-free and cell-based assays. Significantly, 1a prevents autophagy in human cells induced either by starvation or by an mTOR inhibitor. In silico modeling and kinetic data revealed that 1a could function as an ATP-competitive inhibitor of Vps34. Moreover, it suppressed autophagy in vivo and without inducing heart or liver damage in mice. 1a could be utilized as a new motif for more selective and efficacious antagonists of Vps34 for the potential treatment of autophagy-related human diseases.