The pharmacological properties of chrysophanol, the recent advances

The phytochemistry and pharmacology of three Rheum species: A comprehensive review with future perspectives

BACKGROUND

Rheum palmatum, R. tanguticum, and R. officinale, integral species of the genus Rheum, are widely used across global temperate and subtropical regions. These species are incorporated in functional foods, medicines, and cosmetics, recognized for their substantial bioactive components.

PURPOSE

This review aims to synthesize developments from 2014 to 2023 concerning the botanical characteristics, ethnopharmacology, nutritional values, chemical compositions, pharmacological activities, mechanisms of action, and toxicity of these species.

METHODS

Data on the three Rheum species were gathered from a comprehensive review of peer-reviewed articles, patents, and clinical trials accessed through PubMed, Google Scholar, Web of Science, and CNKI.

RESULTS

The aerial parts are nutritionally rich, providing essential amino acids, fatty acids, and minerals, suitable for use as health foods or supplements. Studies have identified 143 chemical compounds, including anthraquinones, anthrones, flavonoids, and chromones, which contribute to their broad pharmacological properties such as laxative, anti-diarrheal, neuroprotective, hepatoprotective, cardiovascular, antidiabetic, antitumor, anti-inflammatory, antiviral, and antibacterial effects. Notably, the materials science approach has enhanced understanding of their medicinal capabilities through the evaluation of bioactive compounds in different therapeutic contexts.

CONCLUSION

As medicinal and economically significant herb species, Rheum species provide both edible aerial parts and medicinal underground components that offer substantial health benefits. These characteristics present new opportunities for developing nutritional ingredients and therapeutic products, bolstering the food and pharmaceutical industries.

The Water Extract of Rhubarb Prevents Ischemic Stroke by Regulating Gut Bacteria and Metabolic Pathways

Rhubarb (RR), Chinese name Dahuang, is commonly used in the treatment of ischemic stroke (IS). However, its potential mechanism is not fully elucidated. This study intended to verify the effect of RR on IS and investigate the possible mechanism of RR in preventing IS. IS in male rats was induced by embolic middle cerebral artery occlusion (MCAO) surgery, and drug administration was applied half an hour before surgery. RR dramatically decreased the neurological deficit scores, the cerebral infarct volume, and the cerebral edema rate, and improved the regional cerebral blood flow (rCBF) and histopathological changes in the brain of MCAO rats. The 16S rRNA analysis showed the harmful microbes such as Fournierella and Bilophila were decreased, and the beneficial microbes such as Enterorhabdus, Defluviitaleaceae, Christensenellaceae, and Lachnospira were significantly increased, after RR pretreatment. 1H-nuclear magnetic resonance (1H-NMR) was used to detect serum metabolomics, and RR treatment significantly changed the levels of metabolites such as isoleucine, valine, N6-acetyllysine, methionine, 3-aminoisobutyric acid, N, N-dimethylglycine, propylene glycol, trimethylamine N-oxide, myo-inositol, choline, betaine, lactate, glucose, and lipid, and the enrichment analysis of differential metabolites showed that RR may participate in the regulation of amino acid metabolism and energy metabolism. RR exerts the role of anti-IS via regulating gut bacteria and metabolic pathways.

Anthraquinones against Cryptococcus neoformans sensu stricto: antifungal interaction, biofilm inhibition and pathogenicity in the Caenorhabditis elegans model

Introduction. Cryptococcal biofilms have been associated with persistent infections and antifungal resistance. Therefore, strategies, such as the association of natural compounds and antifungal drugs, have been applied for the prevention of biofilm growth. Moreover, the Caenorhabditis elegans pathogenicity model has been used to investigate the capacity to inhibit the pathogenicity of Cryptococcus neoformans sensu stricto.Hypothesis. Anthraquinones and antifungals are associated with preventing C. neoformans sensu stricto biofilm formation and disrupting these communities. Antraquinones reduced the C. neoformans sensu stricto pathogenicity in the C. elegans model.Aim. This study aimed to evaluate the in vitro interaction between aloe emodin, barbaloin or chrysophanol and itraconazole or amphotericin B against growing and mature biofilms of C. neoformans sensu stricto.Methodology. Compounds and antifungal drugs were added during biofilm formation or after 72 h of growth. Then, the metabolic activity was evaluated by the MTT reduction assay, the biomass by crystal-violet staining and the biofilm morphology by confocal laser scanning microscopy. C. neoformans sensu stricto's pathogenicity was investigated using the nematode C. elegans. Finally, pathogenicity inhibition by aloe emodin, barbarloin and chrysophanol was investigated using this model.Results. Anthraquinone-antifungal combinations affected the development of biofilms with a reduction of over 60 % in metabolic activity and above 50 % in biomass. Aloe emodin and barbaloin increased the anti-biofilm activity of antifungal drugs. Chrysophanol potentiated the effect of itraconazole against C. neoformans sensu stricto biofilms. The C. elegans mortality rate reached 76.7 % after the worms were exposed to C. neoformans sensu stricto for 96 h. Aloe emodin, barbaloin and chrysophanol reduced the C. elegans pathogenicity with mortality rates of 61.12 %, 65 % and 53.34 %, respectively, after the worms were exposed for 96 h to C. neoformans sensu stricto and these compounds at same time.Conclusion. These results highlight the potential activity of anthraquinones to increase the effectiveness of antifungal drugs against cryptococcal biofilms.

Neuroprotective effect of chrysophanol in Alzheimer disease via modulating the Ca2+/EGFR-PLCγ pathway

Chrysophanol (CHR) is an anthraquinone compound found in rhubarb, and it possesses neuroprotective properties. The purpose of this study was to gain a better understanding of its role in Alzheimer's disease (AD). In vivo study, D-galactose combined with intracerebral injection of β-protein 25-35(Aβ25-35) were used to establish AD model rats. In vitro study, Aβ25-35 was used to induce AD model cells. Our results indicated that CHR improves learning and memory in AD model rats and provides protection against neuronal damage in both AD model rats and cells. Additionally, we observed that CHR suppressed the protein expression of p-tau, EGFR, PLCγ, IP3R, and CAM, as well as the mRNA levels of tau, EGFR, PLCγ, IP3R, and CAM. Furthermore, we have confirmed that CHR inhibited the fluorescence expression of calcium ions (Ca2+). In conclusion, the CHR may exert neuroprotective effects in AD by reducing tau phosphorylation through the Ca2+/EGFR-PLCγ pathway.

Possible NLO response and electrical/charge transfer capabilities of natural anthraquinones as p-type organic semiconductors: a DFT approach

CONTEXT

Organic semiconductors (OSCs) have attracted a great deal of interest in recent days. There are various types of OSCs, among which small molecules have various inherent benefits. Further research is needed to advance this new kind of material because the field is still developing, and the current focus is on creating small molecules that exist naturally for OSCs. OSCs with nonlinear optical (NLO) characteristics offer a significant advantage over others. Thus, this study theoretically investigates naturally occurring anthraquinones such as chrysophanol and rhein as potential OSCs, as well as their NLO properties. The calculated properties include the ionization potential (IP), electron affinity (EA), and bandgap (Eg). The FMO energy levels together with the Eg, IP (8.17-8.53 eV), and EA (1.87-2.44 eV) suggest the semiconductor nature of the studied compounds. The calculated values of reorganization energy (λ) and transfer integrals (V) suggest the p-type character of both molecules. Rhein has the lowest λh (0.19 eV) and Eg (3.28 eV) and the highest Vh, predominantly because of its better p-type character. The polarizability increases due to the presence of an electron-withdrawing substituent, leading to better NLO performance for Rhein, which is supported by its lower LUMO and Eg values.

METHODS

The studied molecules were optimized with the DFT/B3LYP-GD3/6-31+G(d,p) method using Gaussian 16 software. The crystal structure was simulated with Materials Studio 7.0, and the V values were calculated with the ADF package. The CDD and DOS plots were obtained with the Multiwfn 3.8 program.

Construction of chrysophanol loaded nanoparticles with N-octyl-O-sulfate chitosan for enhanced nephroprotective effect

Natural occurring anthraquinone like chrysophanol has been studied because of its anti-diabetic, anti-tumor, anti-inflammatory, hepatoprotective and neuroprotective properties. Nonetheless, its poor water solubility and unstable nature are big concerns in achieving efficient delivery and associated pharmacokinetic and pharmacodynamic effects. Herein, this study sought to solve the above-mentioned problem through development of chrysophanol-loaded nanoparticles to enhance the bioavailability of chrysophanol and to evaluate its anti-renal fibrosis effect in rats. After synthesis of a safe N-octyl-O-sulfate chitosan, we used it to prepare chrysophanol-loaded nanoparticles through dialysis technique before we performed and physical characterization. Also, we tested the stability of the nanoparticles for 21 days at 4 °C and room temperature (25 °C) and evaluated their pharmacokinetics and anti-renal fibrosis effect in rat model of chronic kidney disease (CKD). In terms of results, the nano-preparation demonstrated an acceptable narrow size distribution, wherein the encapsulation rate, size, polydispersed index (PDI) and electrokinetic potential at room temperature were respectively 83.41±0.89 %, 364.88±13.62 nm, 0.192±0.015 and 23.78±1.39 mV. During 21 days of storage, we observed that size of particles and electrokinetic potential altered slightly but the difference was statistically insignificant (p > 0.05). Also, in vitro release studies showed that the formulation reached 84.74 % at 24 h. Chrysophanol nanoparticles showed a 2.57-fold increase in bioavailability compared to unformulated chrysophanol. More importantly, chrysophanol nanoparticles demonstrated certain renal internalization properties and anti-renal fibrosis effects, which could ultimately result in reduced blood-urea nitrogen (BUN), kidney-injury molecule-1 (KIM-1) and serum creatinine (SCr) levels in model rats. In conclusion, the prepared chrysophanol-loaded nanoparticles potentially increased bioavailability and enhanced nephroprotective effects of chrysophanol.

Chrysophanol improves memory impairment and cell injury by reducing the level of ferroptosis in Aβ25-35 treated rat and PC12 cells

Alzheimer's disease (AD) is a common age-related chronic and neurodegenerative disease that has become a global health problem. AD pathogenesis is complex, and the clinical efficacy of commonly used anti-AD drugs is suboptimal. Recent research has revealed a close association between AD-induced damage and the activation of ferroptosis signaling pathways. Chrysophanol (CHR) the principal medicinal component of Rhubarb, has been reported to have anti-AD effects and can reduce ROS levels in AD-damaged models. AD has been linked to the activation of ferroptosis signaling pathways, which has an important feature of higher levels of reactive oxygen species (ROS). Therefore, the present study explored whether CHR had an anti-AD effect by regulating the ferroptosis levels in AD injury models. Morris water maze, novel object recognition test, Y-maze test, Hematoxylin-eosin (H&E) staining, western blotting, ROS measurement, GPx activity measurement, LPO measurement, transmission electron microscopy, live/dead cell staining were used to investigate the changes in spatial memory level and ferroptosis level in AD model, and the intervention effect of CHR. CHR improved the spatial memory level of AD rat models, reduced the level of hippocampal neuron damage, and improved the survival rate of PC12 cells damaged by β-amyloid (Aβ). Meanwhile, CHR increased glutathione peroxidase-4 (GPX4) protein expression, GPx activity, and GSH, decreased ROS and LPO levels in AD rat models and Aβ-damaged PC12 cells, and improved mitochondrial pathological damage. Our findings suggest that CHR may play a protective role in AD injury by lowering ferroptosis levels, which may provide a potential pathway for developing drugs for AD. However, the mechanism of CHR's role requires further investigation.

Therapeutic Potential of 1,8-Dihydroanthraquinone Derivatives for Breast Cancer

Breast cancer (BC) is the most common malignancy among women worldwide. In recent years, significant progress has been made in BC therapy. However, serious side effects resulting from the use of standard chemotherapeutic drugs, as well as the phenomenon of multidrug resistance (MDR), limit the effectiveness of approved therapies. Advanced research in the BC area is necessary to create more effective and safer forms of therapy to improve the outlook for individuals diagnosed with this aggressive neoplasm. For decades, plants and natural products with anticancer properties have been successfully utilized in treating various medical conditions. Anthraquinone derivatives are tricyclic secondary metabolites of natural origin that have been identified in plants, lichens, and fungi. They represent a few botanical families, e.g., Rhamnaceae, Rubiaceae, Fabaceae, Polygonaceae, and others. The review comprehensively covers and analyzes the most recent advances in the anticancer activity of 1,8-dihydroanthraquinone derivatives (emodin, aloe-emodin, hypericin, chrysophanol, rhein, and physcion) applied both individually, or in combination with other chemotherapeutic agents, in in vitro and in vivo BC models. The application of nanoparticles for in vitro and in vivo evidence in the context of 1,8-dihydroanthraquinone derivatives was also described.

Anthrol reductases: discovery, role in biosynthesis and applications in natural product syntheses

Covering: up to 2023Short-chain dehydrogenase/reductases (SDR) are known to catalyze the regio- and stereoselective reduction of a variety of substrate types. Investigations of the deoxygenation of emodin to chrysophanol has led to the discovery of the anthrol reductase activity of an SDR, MdpC involved in monodictyphenone biosynthesis of Aspergillus nidulans and provided access to (R)-dihydroanthracenone, a putative biosynthetic intermediate. This facilitated the identification of several MdpC-related enzymes involved in the biosynthesis of aflatoxins B1, cladofulvin, neosartorin, agnestins and bisanthraquinones. Because of their ability to catalyze the reduction of hydroanthraquinone (anthrols) using NADPH, they were named anthrol reductases. This review provides a comprehensive summary of all the anthrol reductases that have been identified and characterized in the last decade along with their role in the biosynthesis of natural products. In addition, the applications of these enzymes towards the chemoenzymatic synthesis of flavoskyrins, modified bisanthraquinones, 3-deoxy anthraquinones, chiral cycloketones and β-halohydrins have been discussed.

Natural products in non-alcoholic fatty liver disease (NAFLD): Novel lead discovery for drug development

With changing lifestyles, non-alcoholic fatty liver disease (NAFLD) has become the most prevalent liver disease worldwide. A substantial increase in the incidence, mortality, and associated burden of NAFLD-related advanced liver disease is expected. Currently, the initial diagnosis of NAFLD is still based on ultrasound and there is no approved treatment method. Lipid-lowering drugs, vitamin supplementation, and lifestyle improvement treatments are commonly used in clinical practice. However, most lipid-lowering drugs can produce poor patient compliance and specific adverse effects. Therefore, the exploration of bio-diagnostic markers and active lead compounds for the development of innovative drugs is urgently needed. More and more studies have reported the anti-NAFLD effects and mechanisms of natural products (NPs), which have become an important source for new drug development to treat NAFLD due to their high activity and low side effects. At present, berberine and silymarin have been approved by the US FDA to enter clinical phase IV studies, demonstrating the potential of NPs against NAFLD. Studies have found that the regulation of lipid metabolism, insulin resistance, oxidative stress, and inflammation-related pathways may play important roles in the process. With the continuous updating of technical means and scientific theories, in-depth research on the targets and mechanisms of NPs against NAFLD can provide new possibilities to find bio-diagnostic markers and innovative drugs. As we know, FXR agonists, PPARα agonists, and dual CCR2/5 inhibitors are gradually coming on stage for the treatment of NAFLD. Whether NPs can exert anti-NAFLD effects by regulating these targets or some unknown targets remains to be further studied. Therefore, the study reviewed the potential anti-NAFLD NPs and their targets. Some works on the discovery of new targets and the docking of active lead compounds were also discussed. It is hoped that this review can provide some reference values for the development of non-invasive diagnostic markers and new drugs against NAFLD in the clinic.

A chromosome-scale Rhubarb (Rheum tanguticum) genome assembly provides insights into the evolution of anthraquinone biosynthesis

Rhubarb is the collective name for various perennial plants from the genus Rheum L. and the Polygonaceae family. They are one of the most ancient, commonly used, and important herbs in traditional Chinese medicine. Rhubarb is a major source of anthraquinones, but how they are synthesized remains largely unknown. Here, we generate a genome sequence assembly of one important medicinal rhubarb R. tanguticum at the chromosome level, with 2.76 Gb assembled into 11 chromosomes. The genome is shaped by two recent whole-genome duplication events and recent bursts of retrotransposons. Metabolic analyses show that the major anthraquinones are mainly synthesized in its roots. Transcriptomic analysis reveals a co-expression module with a high correlation to anthraquinone biosynthesis that includes key chalcone synthase genes. One CHS, four CYP450 and two BGL genes involved in secondary metabolism show significantly upregulated expression levels in roots compared with other tissues and clustered in the co-expression module, which implies that they may also act as candidate genes for anthraquinone biosynthesis. This study provides valuable insights into the genetic bases of anthraquinone biosynthesis that will facilitate improved breeding practices and agronomic properties for rhubarb in the future.

Antibacterial activities of anthraquinones: structure-activity relationships and action mechanisms

With the increasing prevalence of untreatable infections caused by antibiotic-resistant bacteria, the discovery of new drugs from natural products has become a hot research topic. The antibacterial activity of anthraquinones widely distributed in traditional Chinese medicine has attracted much attention. Herein, the structure and activity relationships (SARs) of anthraquinones as bacteriostatic agents are reviewed and elucidated. The substituents of anthraquinone and its derivatives are closely related to their antibacterial activities. The stronger the polarity of anthraquinone substituents is, the more potent the antibacterial effects appear. The presence of hydroxyl groups is not necessary for the antibacterial activity of hydroxyanthraquinone derivatives. Substitution of di-isopentenyl groups can improve the antibacterial activity of anthraquinone derivatives. The rigid plane structure of anthraquinone lowers its water solubility and results in the reduced activity. Meanwhile, the antibacterial mechanisms of anthraquinone and its analogs are explored, mainly including biofilm formation inhibition, destruction of the cell wall, endotoxin inhibition, inhibition of nucleic acid and protein synthesis, and blockage of energy metabolism and other substances.

Recent advances in the discovery of plant-derived antimicrobial natural products to combat antimicrobial resistant pathogens: insights from 2018-2022

Covering: 2018 to 2022Antimicrobial resistance (AMR) poses a significant global health threat. There is a rising demand for innovative drug scaffolds and new targets to combat multidrug-resistant bacteria. Before the advent of antibiotics, infections were treated with plants chosen from traditional medicine practices. Of Earth's 374 000 plant species, approximately 9% have been used medicinally, but most species remain to be investigated. This review illuminates discoveries of antimicrobial natural products from plants covering 2018 to 2022. It highlights plant-derived natural products with antibacterial, antivirulence, and antibiofilm activity documented in lab studies. Additionally, this review examines the development of novel derivatives from well-studied parent natural products, as natural product derivatives have often served as scaffolds for anti-infective agents.

Advances in mitophagy and mitochondrial apoptosis pathway-related drugs in glioblastoma treatment

Glioblastoma (GBM) is the most common malignant tumor of the central nervous system (CNS). It is a leading cause of death among patients with intracranial malignant tumors. GBM exhibits intra- and inter-tumor heterogeneity, leading to drug resistance and eventual tumor recurrence. Conventional treatments for GBM include maximum surgical resection of glioma tissue, temozolomide administration, and radiotherapy, but these methods do not effectively halt cancer progression. Therefore, development of novel methods for the treatment of GBM and identification of new therapeutic targets are urgently required. In recent years, studies have shown that drugs related to mitophagy and mitochondrial apoptosis pathways can promote the death of glioblastoma cells by inducing mitochondrial damage, impairing adenosine triphosphate (ATP) synthesis, and depleting large amounts of ATP. Some studies have also shown that modern nano-drug delivery technology targeting mitochondria can achieve better drug release and deeper tissue penetration, suggesting that mitochondria could be a new target for intervention and therapy. The combination of drugs targeting mitochondrial apoptosis and autophagy pathways with nanotechnology is a promising novel approach for treating GBM.This article reviews the current status of drug therapy for GBM, drugs targeting mitophagy and mitochondrial apoptosis pathways, the potential of mitochondria as a new target for GBM treatment, the latest developments pertaining to GBM treatment, and promising directions for future research.

Optimal timing of free total rhubarb anthraquinones on immune regulation in rats with severe acute pancreatitis

ETHNOPHARMACOLOGICAL RELEVANCE

Rhubarb is the peeled and dried root of Rheum palmatum L., Rheum tanguticum Maxim. ex Balf. or Rheum officinale Baill. Free total rhubarb anthraquinones (FTRAs) isolated and extracted from rhubarb display the beneficial effects of anti-inflammation and immunological modulation. The timing of immune regulation is a major problem in the immunotherapy for severe acute pancreatitis (SAP). several studies reported that FTRAs could reduce systemic inflammatory responses by inhibiting early immune overactivity in the gut in rats with SAP. But, the optimal timing of rhubarb and FTRAs administration is not clear in clinical practice. Therefore, the time window for the best efficacy of rhubarb and FTRAs in the treatment of SAP patients should be further elucidated.

AIM OF THE STUDY

The main purpose of the present study was to evaluate the efficacy and optimal timing of immune modulation with FTRAs in the treatment of SAP in rats.

MATERIALS AND METHODS

FTRAs (22.5, 45 and 90 mg/kg), Rhubarb (RHU) (900 mg/kg, positive control) or normal saline (vehicle control) were initiated at 0 (immediately), 48 and 72 h every 12 h for three times in total. The therapeutic effects of FTRAs and RHU on pancreas and intestinal tissues injury, secondary infection with pseudomonas aeruginosa (PA), amylase, lipase, D-lactic acid (DLA), endotoxin (ET), proinflammatory and anti-inflammatory cytokines, macrophages, dendritic cells and regulatory T cells (Tregs) in the blood, small intestine and/or mesenteric lymph node (MLN) were determined in rats with SAP after treatment.

RESULTS

The results showed that administration of FTRAs at 0 h was superior to 48 h and 72 h, which significantly protected the injury of pancreas and intestinal tissues, reduced the mortality induced by secondary infection with PA, decreased the levels of amylase, lipase, DLA, ET, tumor necrosis factor α (TNF-α), interleukin 1β (IL-1β), IL-6, IL-8, IL-18 and Tregs, and increased the levels of IL-4, sTNF-αR, macrophages and dendritic cells, secretary immunoglobulin A (SIgA) in the blood and/or small intestinal tissues in rats with SAP.

CONCLUSIONS

In conclusion, our studies indicate that the treatment window of FTRAs for SAP is within 48 h of development, administration of FTRAs at the early stage (0 h, immune overreaction period) was the optimal time and superior to that of 48 h and 72 h for its therapeutic efficacy. The earlier the administration of FTRAs, the better the therapeutic efficacy. Therefore, our data may provide a scientific rationale for the clinical application and optimal timing of FTRAs in the treatment of SAP.

Induction of Nrf2-EpRE-mediated gene expression by hydroxyanthraquinones present in extracts from traditional Chinese medicine and herbs

Hydroxyanthraquinones that can be present in traditional Chinese medicine (TCM) and herbal extracts have claimed beneficial intestinal effects. We examined the ability of a panel hydroxyanthraquinones, and methanolic extracts from selected TCM and herbal granules to activate Nrf2-EpRE mediated gene expression using a reporter-gene assay. The results indicate that purpurin, aloe-emodin, 2-hydroxy-3-methylanthraquinone and rhein induced Nrf2 mediated gene expressions with a high induction factor (IFs>10), with BMCL₁₀ values (the lower confidence limit of the concentration giving 10% added response above background) of 16 μM, 1.1 μM, 23 μM and 2.3 μM, respectively, while aurantio-obtusin, obtusifolin, rubiadin 1-methyl ether and emodin were less potent (IFs<5), with BMCL₁₀ values for added response above background level of 4.6 μM, 15 μM, 9.8 μM and 3.8 μM, respectively. All TCM extracts and the herbal extracts of Aloe Vera, Polygonum multiflorum, Rubia (cordifolia) and Rheum officinale activated the Nrf2-EpRE pathway. Of the TCM extracts, Chuan-Xin-Lian-Kang-Yan-Pian was the most potent Nrf2-inducer. LC-MS/MS analysis indicated the presence of selected hydroxyanthraquinones in the extracts and herbs, in part explaining their Nrf2-EpRE mediated activity. In conclusion, different hydroxyanthraquinones have different potencies of Nrf2 activation. The Nrf2 activation by extracts from TCM and herbs can be partially explained by the presence of selected hydroxyanthraquinones.

An Overview of Nanoemulgels for Bioavailability Enhancement in Inflammatory Conditions via Topical Delivery

The anti-inflammatory drugs that are generally available possess the disadvantage of hydrophobicity, which leads to poor permeability and erratic bioavailability. Nanoemulgels (NEGs) are novel drug delivery systems that aim to improve the solubility and permeability of drugs across the biological membrane. The nano-sized droplets in the nanoemulsion enhance the permeation of the formulation, along with surfactants and co-surfactants that act as permeation enhancers and can further improve permeability. The hydrogel component of NEG helps to increase the viscosity and spreadability of the formulation, making it ideal for topical application. Moreover, oils that have anti-inflammatory properties, such as eucalyptus oil, emu oil and clove oil, are used as oil phases in the preparation of the nanoemulsion, which shows a synergistic effect with active moiety and enhances its overall therapeutic profile. This leads to the creation of hydrophobic drugs that possess enhanced pharmacokinetic and pharmacodynamic properties, and simultaneously avoid systemic side effects in individuals with external inflammatory disorders. The nanoemulsion's effective spreadability, ease of application, non-invasive administration, and subsequent ability to achieve patient compliance make it more suitable for topical application in the combat of many inflammatory disorders, such as dermatitis, psoriasis, rheumatoid arthritis, osteoarthritis and so on. Although the large-scale practical application of NEG is limited due to problems regarding its scalability and thermodynamic instability, which arise from the use of high-energy approaches during the production of the nanoemulsion, these can be resolved by the advancement of an alternative nanoemulsification technique. Considering the potential advantages and long-term benefits of NEGs, the authors of this paper have compiled a review that elaborates the potential significance of utilizing nanoemulgels in a topical delivery system for anti-inflammatory drugs.

Chrysophanol exerts a protective effect against Aβ25-35-induced Alzheimer's disease model through regulating the ROS/TXNIP/NLRP3 pathway

BACKGROUND

The primary pathogenic factors of Alzheimer's disease (AD) have been identified as oxidative stress, inflammatory damage, and apoptosis. Chrysophanol (CHR) has a good neuroprotective effect on AD, however, the potential mechanism of CHR remains unclear.

PURPOSE

In this study, we focused on the ROS/TXNIP/NLRP3 pathway to determine whether CHR regulates oxidative stress and neuroinflammation.

METHODS

D-galactose and Aβ_25-35 combination were used to build an in vivo model of AD, and the Y-maze test was used to evaluate the learning and memory function of rats. Morphological changes of neurons in the rat hippocampus were observed using hematoxylin and eosin (HE) staining. AD cell model was established by Aβ_25-35 in PC12 cells. The DCFH-DA test identified reactive oxygen species (ROS). The apoptosis rate was determined using Hoechst33258 and flow cytometry. In addition, the levels of MDA, LDH, T-SOD, CAT, and GSH in serum, cell, and cell culture supernatant were detected by colorimetric method. The protein and mRNA expressions of the targets were detected by Western blot and RT-PCR. Finally, molecular docking was used to further verify the in vivo and in vitro experimental results.

RESULTS

CHR could significantly improve learning and memory impairment, reduce hippocampal neuron damage, and reduce ROS production and apoptosis in AD rats. CHR could improve the survival rate, and reduce the oxidative stress and apoptosis in the AD cell model. Moreover, CHR significantly decreased the levels of MDA and LDH, and increased the activities of T-SOD, CAT, and GSH in the AD model. Mechanically, CHR significantly reduced the protein and mRNA expression of TXNIP, NLRP3, Caspase-1, IL-1β, and IL-18, and increase TRX.

CONCLUSIONS

CHR exerts neuroprotective effects on the Aβ_25-35-induced AD model mainly by reducing oxidative stress and neuroinflammation, and the mechanism may be related to ROS/TXNIP/NLRP3 signaling pathway.

Integrated metabolic and transcriptomic profiles reveal the germination-associated dynamic changes for the seeds of Cassia obtusifolia L

INTRODUCTION

The seeds of Cassia obtusifolia L. (Cassiae [C.] semen) have been widely used as both food and traditional Chinese medicine in China.

OBJECTIVES

We aimed to analyze the metabolic mechanisms underlying C. semen germination.

MATERIALS AND METHODS

Different samples of C. semen at various germination stages were collected. These samples were subjected to ¹ H-NMR and UHPLC/Q-Orbitrap-MS-based untargeted metabolomics analysis together with transcriptomics analysis.

RESULTS

A total of 50 differential metabolites (mainly amino acids and sugars) and 20 key genes involved in multiple pathways were identified in two comparisons of different groups (36 h vs 12 h and 84 h vs 36 h). The metabolite-gene network for seed germination was depicted. In the germination of C. semen, fructose and mannose metabolism was activated in the testa rupture period, indicating more energy was needed (36 h). In the embryonic axis elongation period (84 h), the pentose and glucuronate interconversions pathway and the phenylpropanoid biosynthesis pathway were activated, which suggested some nutrient sources (nitrogen and sugar) were in demand. Furthermore, oxygen, energy, and nutrition should be supplied throughout the whole germination process. These global views open up an integrated perspective for understanding the complex biological regulatory mechanisms during the germination process of C. semen.

Network pharmacology and in vitro experimental verification to explore the mechanism of Sanhua decoction in the treatment of ischaemic stroke

CONTEXT

Stroke is an illness with high morbidity, disability and mortality that presents a major clinical challenge. Sanhua decoction (SHD) has been widely used to treat ischaemic stroke in the clinic. However, the potential mechanism of SHD remains unknown.

OBJECTIVE

To elucidate the multitarget mechanism of SHD in ischaemic stroke through network pharmacology and bioinformatics analyses.

MATERIALS AND METHODS

Network pharmacology and experimental validation approach was used to investigate the bioactive ingredients, critical targets and potential mechanisms of SHD against ischaemic stroke. Four herbal names of SHD, 'ischemic stroke' or 'stroke' was used as a keyword to search the relevant databases. SH-SY5Y cells were treated with various concentrations of SHD (12.5, 25, 50 or 100 μg/mL) for 4 h, exposed to oxygen and glucose deprivation (OGD) for 1 h, then reoxygenation for 24 h. The cell viability was detected by MTT, the lactate dehydrogenase (LDH) was evaluated by ELISA, and protein expression was detected by western blots.

RESULTS

SHD treatment increased the survival rate from 65.9 ± 4.3 to 85.56 ± 5.7%. The median effective dose (ED₅₀) was 47.1 μg/mL, the LDH decreased from 288.0 ± 12.0 to 122.8 ± 9.1 U/L and the cell apoptosis rate decreased from 33.6 ± 1.8 to 16.3 ± 1.2%. Western blot analysis revealed that SHD increased the levels of p-PI3k, p-Akt and p-CREB1, and decreased the expression of TNF-α and IL-6.

DISCUSSION AND CONCLUSIONS

This study suggests that SHD protects against cerebral ischaemic injury via regulation of the PI3K/Akt/CREB1 and TNF pathways.

Comparative study of the Rheum tanguticum's chemical contents based on spatial distribution characteristics

Rheum tanguticum (R. tanguticum) has been widely used for the treatment of inflammatory diseases in clinical. However, limited research exist on the quality evaluation of various R. tanguticum locations, which has certain drawbacks. In this study, Fourier-transform infrared spectroscopy (FTIR) and high-performance liquid chromatography (HPLC) were used to comparative study on the chemical contents of R. tanguticum, to clarify the relationship between the chemical contents and the spatial distribution of R. tanguticum. First of all, the FTIR spectra of 18 batches of R. tanguticum were examined. Following the cluster analysis, the FTIR spectra of various production locations differed. To some extent, establishing the double index analysis sequence of common and variation peaks may differentiate distinct production locations of medicinal materials. The HPLC fingerprint of R. tanguticum was constructed to further explore the link between components and their origin. PCA of common peaks of 18 batches of R. tanguticum indicated that R. tanguticum grown in Gannan and Qinghai had a tendency to separate t[2], however this trend was not noticeable. Then, OPLS-DA model was established, and the key differential components of R. tanguticum produced in Gannan and Qinghai were discovered to be R16, R37, R46, and R47 (Aloe emodin) (VIP ≥ 1 and P < 0.05). At last, Pearson's test was used to examine the relationship between longitude, latitude, altitude, and composition. Longitude was significantly positively correlated with R28 and R30 (P < 0.05), and a very significantly positively correlated with R35, R36, R37, R46, and R47 (P < 0.01). Latitude was significantly negatively correlated with R34, R35, and R40 (P < 0.05), and extremely significantly negatively correlated with R28, R30, R36, R37, R46, and R47 (P < 0.01). Altitude was significantly positive correlation with R36 and R37 (P < 0.01). The results of our study can provide insights into R. tanguticum quality control and aid in establishing a natural medication traceability system.

In Vitro, Molecular Docking and In Silico ADME/Tox Studies of Emodin and Chrysophanol against Human Colorectal and Cervical Carcinoma

Anthraquinones (AQs) are present in foods, dietary supplements, pharmaceuticals, and traditional treatments and have a wide spectrum of pharmacological activities. In the search for anti-cancer drugs, AQ derivatives are an important class. In this study, anthraquinone aglycons chrysophanol (Chr), emodin (EM) and FDA-approved anticancer drug fluorouracil were analyzed by molecular docking studies against receptor molecules caspase-3, apoptosis regulator Bcl-2, TRAF2 and NCK-interacting protein kinase (TNIK) and cyclin-dependent protein kinase 2 (CDK2) as novel candidates for future anticancer therapeutic development. The ADMET SAR database was used to predict the toxicity profile and pharmacokinetics of the Chr and EM. Furthermore, in silico results were validated by the in vitro anticancer activity against HCT-116 and HeLa cell lines to determine the anticancer effect. According to the docking studies simulated by the docking program AutoDock Vina 4.0, Chr and EM had good binding energies against the target proteins. It has been observed that Chr and EM show stronger molecular interaction than that of the FDA-approved anticancer drug fluorouracil. In the in vitro results, Chr and EM demonstrated promising anticancer activity in HCT-116 and HeLa cells. These findings lay the groundwork for the potential use of Chr and EM in the treatment of human colorectal and cervical carcinomas.

Bioactive Metabolite Production in the Genus Pyrenophora (Pleosporaceae, Pleosporales)

The genus Pyrenophora includes two important cereal crop foliar pathogens and a large number of less well-known species, many of which are also grass pathogens. Only a few of these have been examined in terms of secondary metabolite production, yet even these few species have yielded a remarkable array of bioactive metabolites that include compounds produced through each of the major biosynthetic pathways. There is little overlap among species in the compounds identified. Pyrenophora tritici-repentis produces protein toxin effectors that mediate host-specific responses as well as spirocyclic lactams and at least one anthraquinone. Pyrenophora teres produces marasmine amino acid and isoquinoline derivatives involved in pathogenesis on barley as well as nonenolides with antifungal activity, while P. semeniperda produces cytochalasans and sesquiterpenoids implicated in pathogenesis on seeds as well as spirocyclic lactams with phytotoxic and antibacterial activity. Less well-known species have produced some unusual macrocyclic compounds in addition to a diverse array of anthraquinones. For the three best-studied species, in silico genome mining has predicted the existence of biosynthetic pathways for a much larger array of potentially toxic secondary metabolites than has yet been produced in culture. Most compounds identified to date have potentially useful biological activity.

PI3K/AKT/mTOR signalling inhibitor chrysophanol ameliorates neurobehavioural and neurochemical defects in propionic acid-induced experimental model of autism in adult rats

Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder marked by social and communication deficits as well as repetitive behaviour. Several studies have found that overactivation of the PI3K/AKT/mTOR signalling pathways during brain development plays a significant role in autism pathogenesis. Overexpression of the PI3K/AKT/mTOR signalling pathway causes neurological disorders by increasing cell death, neuroinflammation, and oxidative stress. Chrysophanol, also known as chrysophanic acid, is a naturally occurring chemical obtained from the plant Rheum palmatum. This study aimed to examine the neuroprotective effect of CPH on neurobehavioral, molecular, neurochemical, and gross pathological alterations in ICV-PPA induced experimental model of autism in adult rats. The effects of ICV-PPA on PI3K/AKT/mTOR downregulation in the brain were studied in autism-like rats. Furthermore, we investigated how CPH affected myelin basic protein (MBP) levels in rat brain homogenate and apoptotic biomarkers such as caspase-3, Bax, and Bcl-2 levels in rat brain homogenate and blood plasma samples. Rats were tested for behavioural abnormalities such as neuromuscular dysfunction using an actophotometer, motor coordination using a beam crossing task (BCT), depressive behaviour using a forced swim test (FST), cognitive deficiency, and memory consolidation using a Morris water maze (MWM) task. In PPA-treated rats, prolonged oral CPH administration from day 12 to day 44 of the experimental schedule reduces autistic-like symptoms. Furthermore, in rat brain homogenates, blood plasma, and CSF samples, cellular, molecular, and cell death markers, neuroinflammatory cytokines, neurotransmitter levels, and oxidative stress indicators were investigated. The recent findings imply that CPH also restores abnormal neurochemical levels and may prevent autism-like gross pathological alterations, such as demyelination volume, in the rat brain.

Chrysophanol Ameliorates Hemin-Induced Oxidative Stress and Endoplasmic Reticulum Stress by Regulating MicroRNA-320-5p/Wnt3a Pathway in HT22 Cells

Oxidative stress, endoplasmic reticulum (ER) stress, and neuronal cell apoptosis have been considered as the main pathogenesis factors of brain injury after intracerebral hemorrhage (ICH). Chrysophanol (CHR) has been proved to have neuroprotective effects, but the role and underlying mechanisms of CHR in ICH remain unclear. HT22 cells were dealt with hemin to mimic an in vitro ICH model and then subjected to treatment with or without CHR. The cell viability, apoptosis, ER stress, and oxidative stress were evaluated by conducting the cell counting kit-8 (CCK-8), TdT-mediated dUTP nick end labeling (TUNEL) staining assays, western blot, and corresponding kit, respectively. Further, microRNA-sequencing, bioinformatic analysis, dual-luciferase reporter method, and rescue experiments were conducted to explore the molecular mechanisms of CHR alleviating hemin-induced ER in HT22 cell. Our data revealed that CHR increased cells viability, antiapoptosis, anti-ER stress, and antioxidative stress under conditions of hemin-induced HT22 cell injury. Mechanically, it was observed that Wnt3a was competitively sponged by miR-320-5p, and CHR activated β-catenin pathway by regulating miR-320-5p/Wnt3a molecular axis. Finally, results from the rescue experiment suggested that CHR inhibited hemin-induced cells apoptosis, ER stress, and oxidative stress through regulating the miR-320-5p/Wnt3a axis in HT22 cells. In conclusion, CHR prevented hemin-induced apoptosis, ER stress, and oxidative stress via inhibiting the miR-320-5p/Wnt3a/β-catenin pathway in HT22 cells. Our results certified that CHR could be served as a promising treatment for brain damage following ICH.

Oral administration of processed Cassia obtusifolia L. seed powder May reduce body weight and cholesterol in overweight patients with schizophrenia: A 36-week randomized, double-blind, controlled trial of high and low doses

ETHNOPHARMACOLOGICAL RELEVANCE

Obesity in patients with schizophrenia is related to antipsychotic drug use, hypertension, diabetes, and dyslipidemia, which are critical risk factors for cardiovascular disease. Cassia seed is a traditional Chinese medicine that can be used to treat various eye disorders. Anthraquinone-containing Cassia seed were used to lower serum levels of fat and cholesterol.

AIM OF STUDY

The effects of Cassia seed powder on body weight and lipids were investigated in overweight or obese patients with schizophrenia.

METHODS

The present study was designed as a double-blind, randomized, controlled trial. Ninety-four patients with schizophrenia who were overweight or obese were assigned to a control group (CG, 47 patients) and treatment group (TG, 47 patients) that received low dose Cassia seed power (0.3 g once daily) and Cassia seed powder (3.0 g once daily), respectively, for 36 weeks. The main outcome was the change in body mass index and waist circumference (WC). The secondary outcome was the change in serum lipids, C-reactive protein, interleukin-6, and glycated hemoglobin.

RESULTS

Seventy-four patients completed the study (n = 36, CG; n = 38, TG). WC was significantly lower at the second (24 weeks, 98.63 ± 9.44 vs 95.80 ± 10.26 cm, p = 0.023), third (36 weeks, 98.35 ± 9.46 vs 95.05 ± 10.07 cm, p = 0.002), and fourth (48 weeks, 98.78 ± 9.48 vs 93.73 ± 10.28 cm, p < 0.001) follow-ups than at baseline in the TG, but only significantly lower than baseline at the fourth follow-up (100.78 ± 13.98 vs 94.03 ± 9.74 cm, p = 0.006); no significant difference in CG was observed at both the second (101.03 ± 13.62 vs 97.35 ± 8,29 cm, p = 0.08) and third (100.55 ± 13.69 vs 96.55 ± 8.29 cm, p = 0.066) follow-up. The difference in serum total cholesterol and low-density lipoprotein levels between the baseline and the third follow-up was greater in the TG than in the CG (149.68 ± 34.85 vs 179.08 ± 75.87 mg/dL, p = 0.033; 84.40 ± 28.06 vs102.08 ± 34.12 mg/dL, p = 0.015, respectively).

CONCLUSION

In patients with schizophrenia who were overweight or obese, oral administration of Cassia seed powder (3.0 g) for 24 weeks and 36 weeks reduced WC, and oral administration of Cassia seed powder for 36 weeks reduced total cholesterol and low-density lipoprotein levels, suggesting that Cassia seed powder aids the management of patients with schizophrenia who are overweight or obese. However, these results are preliminary, and future studies should use larger sample sizes, multiple testing centers, and multiple dosing.

Human Protein Tyrosine Phosphatase 1B (PTP1B): From Structure to Clinical Inhibitor Perspectives

Phosphorylation is an essential process in biological events and is considered critical for biological functions. In tissues, protein phosphorylation mainly occurs on tyrosine (Tyr), serine (Ser) and threonine (Thr) residues. The balance between phosphorylation and dephosphorylation is under the control of two super enzyme families, protein kinases (PKs) and protein phosphatases (PPs), respectively. Although there are many selective and effective drugs targeting phosphokinases, developing drugs targeting phosphatases is challenging. PTP1B, one of the most central protein tyrosine phosphatases (PTPs), is a key player in several human diseases and disorders, such as diabetes, obesity, and hematopoietic malignancies, through modulation of different signaling pathways. However, due to high conservation among PTPs, most PTP1B inhibitors lack specificity, raising the need to develop new strategies targeting this enzyme. In this mini-review, we summarize three classes of PTP1B inhibitors with different mechanisms: (1) targeting multiple aryl-phosphorylation sites including the catalytic site of PTP1B; (2) targeting allosteric sites of PTP1B; (3) targeting specific mRNA sequence of PTP1B. All three types of PTP1B inhibitors present good specificity over other PTPs and are promising for the development of efficient small molecules targeting this enzyme.

Herbal Medicines for Constipation and Phytochemical Comparison of Active Components

Constipation is a very common medical condition worldwide, negatively affecting patients' quality of life and healthcare system. Rhubarb, senna leaf, and aloe are three frequently used herbal medications for achieving regular bowel movement. Rhubarb is also a key ingredient in MaZiRenWan, a Chinese medicine formula used every so often for constipation in oriental countries. We reviewed and summarized the major chemical components from these three botanicals, including dianthrones, anthraquinone glycosides, free anthraquinones, and other polyphenols. The purgative actions of these constituents have been compared. Anthraquinone, especially its dianthrone compounds such as sennoside A and sennoside B, as natural stimulant laxatives, possesses significant effects to promote gastrointestinal motility and relieve functional constipation. Furthermore, the safety, reported side effects, and other benefits of anthraquinone compounds are presented. To date, many anti-constipation natural products are being used but their research is relatively limited, and thus, more investigations in this field are indeed needed.

Fuzzy identification of bioactive components for different efficacies of rhubarb by the back propagation neural network association analysis of UPLC-Q-TOF/MSE and integrated effects

Background

Rhei Radix et Rhizoma (rhubarb), as one of the typical representatives of multi-effect traditional Chinese medicines (TCMs), has been utilized in the treatment of various diseases due to its multicomponent nature. However, there are few systematic investigations for the corresponding effect of individual components in rhubarb. Hence, we aimed to develop a novel strategy to fuzzily identify bioactive components for different efficacies of rhubarb by the back propagation (BP) neural network association analysis of ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry for every data (UPLC-Q-TOF/MS^E) and integrated effects.

Methods

Through applying the fuzzy chemical identification, most components of rhubarb were classified into different chemical groups. Meanwhile the integration effect values of different efficacies can be determined by animal experiment evaluation and multi-attribute comprehensive indexes. Then the BP neural network was employed for association analysis of components and different efficacies by correlating the component contents determined from UPLC-Q-TOF/MS^E profiling and the integration effect values. Finally, the effect contribution of one type of components may be totaled to demonstrate the universal and individual characters for different efficacies of rhubarb.

Results

It suggested that combined anthraquinones, flavanols and their polymers may be the universal character to the multi-functional properties of rhubarb. Other components contributed to the individuality of rhubarb efficacies, including stilbene glycosides, anthranones and their dimers, free anthraquinones, chromones, gallic acid and gallotannins, butyrylbenzenes and their glycosides.

Conclusions

Our findings demonstrated that the bioactive components for different efficacies of rhubarb were not exactly the same and can be systematically differentiated by the network-oriented strategy. These efforts will advance our knowledge and understanding of the bioactive components in rhubarb and provide scientific evidence to support the expansion of its use in clinical applications and the further development of some products based on this medicinal herb.

Supplementary information

The online version contains supplementary material available at 10.1186/s13020-022-00612-9.

Chrysophanol Suppresses Cell Growth via mTOR/PPAR-α Regulation and ROS Accumulation in Cultured Human Tongue Squamous Carcinoma SAS Cells

Oral cancer, a type of head and neck cancer, can pose a significant risk of death unless diagnosed and treated early. Alternative treatments are urgently needed owing to the high mortality rate, limitations of conventional treatments, and many complications. The anthraquinone compound chrysophanol acts as a tumor suppressor on some types of cancer cells. To date, it has not been clarified how chrysophanol affects human tongue squamous carcinoma. This study was aimed to examine the effects of chrysophanol on oral cancer treatment. The results show that chrysophanol caused cell death, reduced the expression of the mammalian target of rapamycin (mTOR)/peroxisome proliferator-activated receptor-alpha (PPAR-α), and increased reactive oxygen species (ROS) production. We also used two ion chelators, deferoxamine (DFO) and liproxstatin-1 (Lipro), to further determine whether chrysophanol inhibits cell growth and regulates mTOR/PPAR-α expression and ROS production, both of which are involved in iron homeostasis. The results show that DFO and Lipro reversed the increase in cell death, downregulation of mTOR/PPAR-α, and decrease in ROS accumulation. In conclusion, chrysophanol inhibits the growth of oral squamous cell carcinoma cells by modulating mTOR/PPAR-α and by causing ROS accumulation.

Neuroprotective Effect of Chrysophanol as a PI3K/AKT/mTOR Signaling Inhibitor in an Experimental Model of Autologous Blood-induced Intracerebral Hemorrhage

OBJECTIVE

Intracerebral hemorrhage (ICH) refers to predominant, sporadic, and non-traumatic bleeding in the brain parenchyma. The PI3K/AKT/mTOR signaling pathway is an important signal transduction pathway regulated by enzyme-linked receptors and has many biological functions in mammals. It plays a key role in neuronal metabolism, gene expression regulation, and tissue homeostasis in the healthy and diseased brain.

METHODS

In the present study, the role of the PI3K/AKT/mTOR pathway inhibitor chrysophanol (CPH) (10 mg/kg and 20 mg/kg, orally) in the improvement of ICH-associated neurological defects in rats was investigated. Autologous blood (20 µL/5 min/unilateral/intracerebroventricular) mimics ICH-like defects involving cellular and molecular dysfunction and neurotransmitter imbalance. The current study also included various behavioral assessments to examine cognition, memory, and motor and neuromuscular coordination. The protein expression levels of PI3K, AKT, and mTOR as well as myelin basic protein and apoptotic markers, such as Bax, Bcl-2, and caspase-3, were examined using ELISA kits. Furthermore, the levels of various neuroinflammatory cytokines and oxidative stress markers were assessed. Additionally, the neurological severity score, brain water content, gross brain pathology, and hematoma size were used to indicate neurological function and brain edema.

RESULTS

CPH was found to be neuroprotective by restoring neurobehavioral alterations and significantly reducing the elevated PI3K, AKT, and mTOR protein levels, and modulating the apoptotic markers such as Bax, Bcl-2, and caspase-3 in rat brain homogenate. CPH substantially reduced the inflammatory cytokines like interleukin (IL)-1β, IL-6, and tumor necrosis factor-α. CPH administration restored the neurotransmitters GABA, glutamate, acetylcholine, dopamine, and various oxidative stress markers.

CONCLUSION

Our results show that CPH may be a promising therapeutic approach for overcoming neuronal damage caused by the overexpression of the PI3K/AKT/mTOR signaling pathway in ICH-induced neurological dysfunctions in rats.

Neuroprotective Effect of Chrysophanol as a PI3K/AKT/mTOR Signaling Inhibitor in an Experimental Model of Autologous Blood-induced Intracerebral Hemorrhage

OBJECTIVE

Intracerebral hemorrhage (ICH) refers to predominant, sporadic, and non-traumatic bleeding in the brain parenchyma. The PI3K/AKT/mTOR signaling pathway is an important signal transduction pathway regulated by enzyme-linked receptors and has many biological functions in mammals. It plays a key role in neuronal metabolism, gene expression regulation, and tissue homeostasis in the healthy and diseased brain.

METHODS

In the present study, the role of the PI3K/AKT/mTOR pathway inhibitor chrysophanol (CPH) (10 mg/kg and 20 mg/kg, orally) in the improvement of ICH-associated neurological defects in rats was investigated. Autologous blood (20 µL/5 min/unilateral/intracerebroventricular) mimics ICH-like defects involving cellular and molecular dysfunction and neurotransmitter imbalance. The current study also included various behavioral assessments to examine cognition, memory, and motor and neuromuscular coordination. The protein expression levels of PI3K, AKT, and mTOR as well as myelin basic protein and apoptotic markers, such as Bax, Bcl-2, and caspase-3, were examined using ELISA kits. Furthermore, the levels of various neuroinflammatory cytokines and oxidative stress markers were assessed. Additionally, the neurological severity score, brain water content, gross brain pathology, and hematoma size were used to indicate neurological function and brain edema.

RESULTS

CPH was found to be neuroprotective by restoring neurobehavioral alterations and significantly reducing the elevated PI3K, AKT, and mTOR protein levels, and modulating the apoptotic markers such as Bax, Bcl-2, and caspase-3 in rat brain homogenate. CPH substantially reduced the inflammatory cytokines like interleukin (IL)-1β, IL-6, and tumor necrosis factor-α. CPH administration restored the neurotransmitters GABA, glutamate, acetylcholine, dopamine, and various oxidative stress markers.

CONCLUSION

Our results show that CPH may be a promising therapeutic approach for overcoming neuronal damage caused by the overexpression of the PI3K/AKT/mTOR signaling pathway in ICH-induced neurological dysfunctions in rats.

A biocatalytic approach towards the preparation of natural deoxyanthraquinones and their impact on cellular viability

Natural deoxyanthraquinones synthesized using a chemoenzymatic approach and tested for cell viability shows less toxicity compared to the respective anthraquiones.

Potential Natural Compounds for the Prevention and Treatment of Nonalcoholic Fatty Liver Disease: A Review on Molecular Mechanisms

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) is a kind of metabolic stress-induced liver injury closely related to insulin resistance and genetic susceptibility, and there is no specific drug for its clinical treatment currently. In recent years, a large amount of literature has reported that many natural compounds extracted from traditional Chinese medicine (TCM) can improve NAFLD through various mechanisms. According to the latest reports, some emerging natural compounds have shown great potential to improve NAFLD but are seldom used clinically due to the lacking special research.

PURPOSE

This paper aims to summarize the molecular mechanisms of the potential natural compounds on improving NAFLD, thus providing a direction and basis for further research on the pathogenesis of NAFLD and the development of effective drugs for the prevention and treatment of NAFLD.

METHODS

By searching various online databases, such as Web of Science, SciFinder, PubMed, and CNKI, NAFLD and these natural compounds were used as the keywords for detailed literature retrieval.

RESULTS

The pathogenesis of NAFLD and the molecular mechanisms of the potential natural compounds on improving NAFLD have been reviewed.

CONCLUSION

Many natural compounds from traditional Chinese medicine have a good prospect in the treatment of NAFLD, which can serve as a direction for the development of anti-NAFLD drugs in the future.

Pharmacology, Toxicology, and Metabolism of Sennoside A, A Medicinal Plant-Derived Natural Compound

Sennoside A (SA) is a natural dianthrone glycoside mainly from medicinal plants of Senna and Rhubarb, and used as a folk traditional irritant laxative and slimming health food. Accumulating evidences suggest that SA possesses numerous pharmacological properties, such as laxative, anti-obesity, hypoglycemic, hepatoprotective, anti-fibrotic, anti-inflammatory, anti-tumor, anti-bacterial, anti-fungal, anti-viral, and anti-neurodegenerative activities. These pharmacological effects lay the foundation for its potential application in treating a variety of diseases. However, numerous published studies suggest that a long-term use of SA in large doses may have some adverse effects, including the occurrence of melanosis coli and carcinogenesis of colon cancer, thereby limiting its clinical use. It remains to be established whether SA or its metabolites are responsible for the pharmacological and toxicity effects. In this review, the latest advances in the pharmacology, toxicology, and metabolism of SA were summarizedbased on its biological characteristics and mechanism.

Characterization of natural herbal medicines by thin-layer chromatography combined with laser ablation-assisted direct analysis in real-time mass spectrometry

The characterization and quality control of natural herbal medicines, such as traditional Chinese medicines (TCMs), is of great significance to ensure their potential efficacy and avoid severe side effects. Thin-layer chromatography (TLC) is a simple and classic approach for examining quality marker of natural products. Nevertheless, it is more difficult to further characterize the compounds adsorbed on the TLC plate. Herein, we reported a simple setup of laser ablation-assisted direct analysis in real-time mass spectrometry (LA-DART-MS), in which the coupling of mass spectrometry information to provide a predominant dimension in the identification of unknown chemical compositions separated on standard TLC plates, and it was applied for rapid characterization of various kinds of natural herbal medicines. The results showed that the introduction of low-cost small laser pointer had significantly improved the desorption process. The system was successfully applied in the analysis of alkaloids, flavonoids, anthraquinones, volatile oils, glycosides, organic acids, and eight different TCMs including Sophorae Flavescentis Radix, Angelicae Sinensis Radix, Acori Tatarinowii Rhizoma, Phellodendri Chinensis Cortex, Picrasmae Ramulus et Folium, Gynura Japonica, Rhei Radix et Rhizoma and Dendrobii Caulis. The obtained limits of detection (LODs) of this method for various types of reference substances were in the range of 4.6-162.2 ng/band on TLC plates. Furthermore, the quality control and identification of different species of Dendrobii Caulis herb was achieved. This study combines the advantages of TLC and ambient mass spectrometry to provide a good choice for the screening and identification of active ingredients and the quality evaluation of botanical samples.

Anthraquinones from Aloe spp. inhibit Cryptococcus neoformans sensu stricto: effects against growing and mature biofilms

This study aimed to evaluate the in vitro effect of aloe emodin, barbaloin and chrysophanol on growing and mature biofilms of Cryptococcus neoformans sensu stricto. The compounds were added at the moment of inducing biofilm growth or after growth for 72 h to evaluate their effects on growing and mature biofilms, respectively. Then, biofilm biomass was evaluated by crystal violet staining and metabolic activity by the XTT reduction assay. Morphological alterations were also evaluated by laser scanning confocal microscopy. Aloe emodin and barbaloin affected growing biofilms and disrupted mature biofilms, reducing metabolic activity by > 60% and biomass by > 70%. Chrysophanol only inhibited mature biofilms, but to a lesser extent. In conclusion, anthraquinones, especially aloe emodin and barbaloin, show a relevant effect against growing and mature biofilms of C. neoformans sensu stricto.

Q-marker Prediction Analysis of Rhubarb in Fengyin Decoction Based on Fingerprint and Network Pharmacology

Fengyin Decoction (FYD) is a traditional Chinese medicine for the treatment of epilepsy and wind paralysis. However, the potential antiepileptic active component in rhubarb (which is the most effective Chinese medicine in FYD) has not been defined. In this study, we analyzed and predicted the potential quality marker (Q-marker) of rhubarb in FYD based on fingerprint and network pharmacology. The fingerprints of FYD and rhubarb were established to analyze the transmission law of active components. Ultra-high performance liquid chromatography (UPLC) was used to study quantitatively the active components obtained by different extraction methods of FYD. Combined with network pharmacological analysis, a “components-targets-pathways” network was constructed to predict the potential Q-marker. Eight peaks were identified by FYD fingerprint: aloe-emodin, rhein, emodin, chrysophanol, physcion, cinnamaldehyde, 6-gingerol, and glycyrrhizic acid ammonium salt. The determination of the 8 active components in FYD with different extraction methods suggested that rhubarb anthraquinone may be a potential antiepileptic active component. Twelve core components, 19 targets, and 21 pathways of rhubarb were screened by network pharmacology, which further demonstrated that rhubarb played a role mainly through these components, targets, and pathways. We preliminarily predicted that compounds such as rhubarb anthraquinones were a potential Q-marker. The UPLC fingerprint and the content determination method of the 8 components established in this study were effective and feasible. The findings in this study may provide a reference for further study of quality control of FYD and lay a theoretical foundation for the study of its action mechanism. In addition, our study may provide a novel idea for the study of the Q-marker of other classical compound traditional Chinese medicines.

Prevention of UV-induced skin cancer in mice by gamma oryzanol-loaded nanoethosomes

AIMS

Skin cancer is the most widespread cancer worldwide, mainly caused by exposure to ultraviolet radiation (UV) in sunlight. Utilizing topical preventive agents in routinely daily used cosmetics may prevent UV-related skin damages and skin cancers. γ-Oryzanol (GO) is a natural component derived from rice bran oil, with potential antioxidant and skin anti-aging properties.

MAIN METHODS

We biologically thorough studied the antioxidant and anticancer effects of GO in vitro to found the effective signaling pathways, then evaluated the sun protection factor of prepared formulation, and finally investigated the long-term preventive effects of GO-loaded nanoethosomes (GO-NEs) against UVB-induced skin cancer in mice.

KEY FINDINGS

GO-NEs could effectively prevent UVB-induced skin cancer.

SIGNIFICANCE

Our results suggest that GO-NEs could be utilized as an innovative ingredient in cosmetics.

Burn Ointment Promotes Cutaneous Wound Healing by Modulating the PI3K/AKT/mTOR Signaling Pathway

Burn ointment (BO) is a clinically useful medicine for the treatment of burns and scalds. However, there is no enough scientific evidence to report the effect of BO on wound healing and its analgesic and anti-inflammatory efficacy. The aim of this work was to evaluate the anti-inflammatory and analgesic efficacy of BO and to reveal the potential wound healing properties and related mechanisms of BO. In this work, the content of active ingredients of BO was determined by high-performance liquid chromatography (HPLC). Two animal models of inflammation were used to study its anti-inflammatory activity, and a hot plate method was used to evaluate its analgesic effect. In addition, mouse incision and rat burn models were used to investigate the effect of BO on the anti-inflammatory and wound healing mechanisms. The results showed that BO was safe for topical application, and BO could significantly inhibit auricular swelling in mice and paw swelling in rats and significantly prolong the latency period of paw licking in the hot plate experiment in mice. It can also accelerate wound healing and repair scars by promoting the formation of new epithelial tissues in rat burn models. In addition, BO significantly downregulated the serum level of TNF-α and significantly increased the serum levels of VEGF and TGF-β1. Also, BO promoted the expression of collagen I and increased the ratio in p-PI3K/PI3K, p-AKT/AKT, and p-mTOR/mTOR pathways. Our results demonstrate the safety and efficacy of BO and suggest that activation of the PI3K/AKT/mTOR signaling pathway may play an important role in the promotion of wound healing by BO.

Kanglexin protects against cardiac fibrosis and dysfunction in mice by TGF-β1/ERK1/2 noncanonical pathway

Cardiac fibrosis is a common pathological manifestation accompanied by various heart diseases, and antifibrotic therapy is an effective strategy to prevent diverse pathological processes of the cardiovascular system. We currently report the pharmacological evaluation of a novel anthraquinone compound (1,8-dihydroxy-6-methyl-9,10-anthraquinone-3-oxy ethyl succinate) named Kanglexin (KLX), as a potent cardioprotective agent with antifibrosis activity. Our results demonstrated that the administration of KLX by intragastric gavage alleviated cardiac dysfunction, hypertrophy, and fibrosis induced by transverse aortic constriction (TAC) surgical operation. Meanwhile, KLX administration relieved endothelial to mesenchymal transition of TAC mice. In TGF β1-treated primary cultured adult mouse cardiac fibroblasts (CFs) and human umbilical vein endothelial cells (HUVECs), KLX inhibited cell proliferation and collagen secretion. Also, KLX suppressed the transformation of fibroblasts to myofibroblasts in CFs. Further studies revealed that KLX-mediated cardiac protection was due to the inhibitory role of TGF-β1/ERK1/2 noncanonical pathway. In summary, our study indicates that KLX attenuated cardiac fibrosis and dysfunction of TAC mice, providing a potentially effective therapeutic strategy for heart pathological remodeling.

Chrysophanol Relieves Cisplatin-Induced Nephrotoxicity via Concomitant Inhibition of Oxidative Stress, Apoptosis, and Inflammation

Cisplatin (CDDP) is one of the most frequently prescribed chemotherapy medications. However, its nephrotoxicity which often leads to acute kidney injury (AKI), greatly limits its clinical application. Chrysophanol (CHR), a mainly active anthraquinone ingredient, possesses various biological and pharmacological activities. In this study, we aimed to investigate the underlying protective mechanisms of CHR against CDDP-induced AKI (CDDP-AKI) using C57BL/6 mouse and human proximal tubule epithelial cells. In vivo, we found that pre-treatment with CHR greatly relieved CDDP-AKI and improved the kidney function and morphology. The mechanistic studies indicated that it might alleviate CDDP-AKI by inhibiting oxidative stress, apoptosis, and IKKβ/IκBα/p65/transcription factor nuclear kappa B (NF-κB) inflammation signaling pathway induced by CDDP. Moreover, we found that the cell viability of HK2 cells reduced by CDDP was partially rescued by CHR pre-incubation. Flow cytometry results further indicated that CHR pre-incubation suppressed CDDP induced cellular reactive oxygen species (ROS) generation and inhibited cell apoptosis in a dose-dependent manner. In summary, our results suggested that CHR might be a novel therapy for CDDP-induced AKI.

Compounds from Natural Sources as Protein Kinase Inhibitors

The advantage of natural compounds is their lower number of side-effects when compared to most synthetic substances. Therefore, over the past several decades, the interest in naturally occurring compounds is increasing in the search for new potent drugs. Natural compounds are playing an important role as a starting point when developing new selective compounds against different diseases. Protein kinases play a huge role in several diseases, like cancers, neurodegenerative diseases, microbial infections, or inflammations. In this review, we give a comprehensive view of natural compounds, which are/were the parent compounds in the development of more potent substances using computational analysis and SAR studies.

Chrysophanol Prevents Lipopolysaccharide-Induced Hepatic Stellate Cell Activation by Upregulating Apoptosis, Oxidative Stress, and the Unfolded Protein Response

Hepatic stellate cell (HSC) activation is a vital driver of liver fibrosis. Recent research efforts have emphasized the clearance of activated HSCs by apoptosis, senescence, or reversion to the quiescent state. LPS induces human HSC activation directly and contributes to liver disease progression. Chrysophanol is an anthraquinone with hepatoprotective and anti-inflammatory effects. This study aimed to investigate the pharmacological effects and mechanisms of chrysophanol in an LPS-induced activated rat HSC cell line (HSC-T6). The fibrosis phenotype was identified from the expression of α-smooth muscle actin (α-SMA), connective tissue growth factor (CTGF), and integrin β1 by western blot analysis. We examined DNA fragmentation by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining. We detected the apoptotic markers p53 and cleaved caspase-3 by western blot analysis. Intracellular ROS were labeled with 2′,7′-dichlorofluorescein diacetate (DCF-DA) and the levels were measured by flow cytometry. Finally, we evaluated the ER stress markers binding immunoglobulin protein (BiP) and C/EBP homologous protein (CHOP) by Western blot analysis. Our results showed that chrysophanol decreased HSC-T6 cell viability in LPS-induced activated HSCs. Chrysophanol increased the expression of α-SMA, CTGF, integrin βI, p53, cleaved caspase-3, and DNA fragmentation. Chrysophanol also elevated ROS levels and increased the expression of BiP and CHOP. Pretreatment with chrysophanol prevented LPS-induced HSC-T6 cell activation by upregulating apoptosis, ROS accumulation, unfolded protein response (UPR) activation, and the UPR proapoptotic effect.

Targeting foam cell formation and macrophage polarization in atherosclerosis: The Therapeutic potential of rhubarb

Atherosclerosis, a chronic inflammatory disease associated with high morbidity and mortality, is characterized by the accumulation of foam cells in the arterial wall. It has long been acknowledged that the formation of foam cells is caused by excess lipid uptake and abnormal cholesterol metabolism function. And increasing evidence shows that inhibiting foam cell formation is a promising way to suppress the development of atherosclerotic lesions. In addition to excess foam cells accumulation, inflammation is another major contributor of atherosclerotic lesions. Recently, macrophage polarization has been demonstrated to play a vital role in the regulation of inflammatory response. Generally, macrophages mainly polarized into two phenotypes: either classically activated pro-inflammatory M1 or alternatively activated anti-inflammatory M2. And targeting macrophage polarization has been considered as a feasible approach to prevent the development of atherosclerosis. At present, the anti-atherosclerosis drugs mainly classified into two types: lipid-lowering drugs and anti-inflammatory drugs. A large part of those drugs belong to western medicine, and various side effects are unavoidable. Interestingly, in recent years, Traditional Chinese medicine has attracted growing attention because of its good efficacy and low negative effects. Rhubarb (called Da Huang in Chinese) is a famous folk medicine with a wide spectrum of pharmacological effects, such as lipid-lowering and anti-inflammatory effects. In this review, we summarized current findings about the regulatory effects of Rhubarb on foam cell formation and macrophage polarization, with emphasis on the molecular mechanisms of action that have been revealed during the past two decades, to better understand its pivotal role in the treatment and prevention of atherosclerosis.